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Park, Malcolm McKenzie. "Flowshop sequencing : a graphical approach /." Connect to thesis, 1990. http://eprints.unimelb.edu.au/archive/00001755.
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Greco, Michael P. "Sequencing policy for a CONWIP production system." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08292008-063311/.
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Cross, Fionnuala Mary. "A model for loading and sequencing a flexible manufacturing cell." Thesis, Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/25656.
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Creswell, Steven Howard 1961. "Solution to a bay design and production sequencing problem." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277124.
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This thesis addresses the problem of setting up a surface mount placement machine for production. The objective is to minimize the number of machine changeovers made during a production run consisting of a number of circuit cards. The solution to the problem involves two separate decisions. The first decision considers determining how to combine feeders together in "bays" or groups of feeders, and how to assign the bays to the circuit cards. The second decision considers the circuit card production sequence. A mathematical programming formulation is given, however, its solution is very difficult for problems of a realistic size. Several heuristic approaches are suggested and used to solve actual and test problems. The heuristic for bay design uses clustering techniques used in Group Technology while the sequencing problem is solved using heuristics based on solution techniques for the Traveling Salesman problem.
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Kircher, Martin. "Understanding and improving high-throughput sequencing data production and analysis." Doctoral thesis, Universitätsbibliothek Leipzig, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-71102.
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Advances in DNA sequencing revolutionized the field of genomics over the last 5 years. New sequencing instruments make it possible to rapidly generate large amounts of sequence data at substantially lower cost. These high-throughput sequencing technologies (e.g. Roche 454 FLX, Life Technology SOLiD, Dover Polonator, Helicos HeliScope and Illumina Genome Analyzer) make whole genome sequencing and resequencing, transcript sequencing as well as quantification of gene expression, DNA-protein interactions and DNA methylation feasible at an unanticipated scale.
In the field of evolutionary genomics, high-throughput sequencing permitted studies of whole genomes from ancient specimens of different hominin groups. Further, it allowed large-scale population genetics studies of present-day humans as well as different types of sequence-based comparative genomics studies in primates. Such comparisons of humans with closely related apes and hominins are important not only to better understand human origins and the biological background of what sets humans apart from other organisms, but also for understanding the molecular basis for diseases and disorders, particularly those that affect uniquely human traits, such as speech disorders, autism or schizophrenia. However, while the cost and time required to create comparative data sets have been greatly reduced, the error profiles and limitations of the new platforms differ significantly from those of previous approaches. This requires a specific experimental design in order to circumvent these issues, or to handle them during data analysis.
During the course of my PhD, I analyzed and improved current protocols and algorithms for next generation sequencing data, taking into account the specific characteristics of these new sequencing technologies. The presented approaches and algorithms were applied in different projects and are widely used within the department of Evolutionary Genetics at the Max Planck Institute of Evolutionary Anthropology. In this thesis, I will present selected analyses from the whole genome shotgun sequencing of two ancient hominins and the quantification of gene expression from short-sequence tags in five tissues from three primates.
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CARNEIRO, SARA SOLANGE PARGA. "PLANNING OF TRUCK SEQUENCING IN ASSEMBLY-TO-ORDER PRODUCTION ENVIRONMENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2013. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=22236@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
A maioria das pesquisas científicas publicadas sobre sequenciamento da produção na indústria automobilística consideram os pedidos já alocados em um dia ou turno de trabalho, desconsiderando especificidades do planejamento da cadeia de suprimentos. Esta dissertação procura contribuir no campo do planejamento da produção, propondo um modelo matemático de programação inteira mista que aborda de maneira integrada dois problemas de otimização fundamentais da cadeia: o problema de seleção de pedidos e o problema de sequenciamento de carros em uma única linha de montagem. A fim de abordar questões bem próximas a realidade, incluindo apresentação de experimentos numéricos com o modelo proposto, utilizou-se como cenário o segmento de caminhões, dentro da indústria automotiva. Considerou-se, como objetivo no modelo, além das abordagens tradicionais (minimizar sobrecarga de trabalho, troca de cores e violação de restrições), a demanda dos clientes com relação a prazos de entrega do pedido – principal reforço para uma indústria que pretende cada vez mais migrar para um ambiente de produção orientado pela demanda.
Most published scientific research on production sequencing in the automotive industry consider orders already allocated in a day or shift, disregarding specificities of supply chain planning. This paper aims to contribute in production planning field, proposing a mathematical model of mixed-integer programming that addresses in a integrated way two fundamental problems from chain: the problem of order selection and car sequencing problem on a single assembly line. In order to approach practical issues, including presentation of numerical experiments from proposed model, the truck segment within the automotive industry was used as scenario. It was considered as objective in the model, beyond traditional approaches (minimize work overload, color changing and violation of restrictions), customer demand with respect promised due dates, the main reinforcement for an industry that increasingly want migrate to a production environment driven by demand.
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Tahboub, Zainel-Abideen Abdul-Majid. "Sequencing to minimize total earliness-tardiness penalties on a single-machine /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487266362338743.
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Won, Seung Gun. "Anaerobic fermentation for biological hydrogen production in a sequencing batch reactor." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44020.
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Biological hydrogen production via anaerobic fermentation of organic waste can be potentially a greener and sustainable technology. Thus far, most research has been conducted using continuous stirred tank reactors (CSTR). Anaerobic sequencing batch reactors (ASBR) have advantages over CSTR, but there are disadvantages in terms of their operation. The overall goal of the thesis research is to enhance hydrogen production by optimizing the operational conditions in an ASBR using agri-food wastewater as substrate.
An ASBR with 6-L working volume was inoculated with sewage sludge from the anaerobic zone of a sewage treatment facility and was not pretreated to select the hydrogen-producing bacteria. Hydrogen productivity was estimated by hydrogen content (%), hydrogen production rate (HPR) and hydrogen yield as the performance indicators in response to changes in pH, hydraulic retention time (HRT), organic loading rate (OLR), and cyclic duration (CD) as the key operational parameters.
Using dairy wastewater as substrate, the suppression of methanogenesis was feasible without pretreatment of inoculum under the conditions of higher OLR and shorter HRT, which favoured hydrogen production. With carbohydrate-rich synthetic wastewater as substrate, the combination of relatively low pH 4.5 and HRT 30 hr was found to be the optimal condition for hydrogen production. For higher hydrogen production, ethanol-to-acetic acid ratio of 1.25 and food-to-microorganism ratio of 0.84 were revealed as threshold values. Higher hydrogen productivity at longer CD was not necessarily accompanied with higher microbial growth that occurred at shorter CD.
Subsequently, real sugar refinery wastewater was used in the tests for biohydrogen production. Based on statistical analysis and curve fitting by the modified Gompertz model of the data as well as microbial identification, the operational setting of (pH 5.5, HRT 10 hr, OLR 15 kg/m³.d) was concluded to be optimal with the performance indicators of (71.8±10.5% H₂, HPR 2.11±0.31 L H₂/L reactor.d and yield 0.95±0.13 mol H₂/mol sucrose). Taxonomic analysis confirmed the presence of dominant hydrogen-producing bacteria among the diverse microbial genera, and in particular, the Clostridia spp. without the pretreatment of inocula. Further studies with the optimization of operational conditions would contribute towards making the best possible decision for ASBR.
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hammadi-Khashouie, Ghorbanali. "Sequencing mixed-model assembly lines in just-in-time production systems." Thesis, Brunel University, 2003. http://bura.brunel.ac.uk/handle/2438/5770.
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This thesis proposes a new simulated annealing approach to solve multiple objective sequencing problems in mixed-model assembly lines. Mixed-model assembly lines are a type of production line where a variety of product models similar in product characteristics are assembled. Such an assembly line is increasingly accepted in industry to cope with the recently observed trend of diversification of customer demands. Sequencing problems are important for an efficient use of mixed-model assembly lines. There is a rich of criteria on which to judge sequences of product models in terms of line utilization. We consider three practically important objectives: the goal of minimizing the variation of the actual production from the desired production, which is minimizing usage variation, workload smoothing in order to reduce the chance of production delays and line stoppages and minimizing total set-ups cost. A considerate line manager would like to take into account all these factors. These are important for an efficient operation of mixed-model assembly lines. They work efficiently and find good solution in a very short time, even when the size of the problem is too large. The multiple objective sequencing problems is described and its mathematical formulation is provided. Simulated annealing algorithms are designed for near or optimal solutions and find an efficiency frontier of all efficient design configurations for the problem. This approach combines the SA methodology with a specific neighborhood search, which in the case of this study is a "swapping two sequence". Two annealing methods are proposed based on this approach, which differ only in cooling and freezing schedules. This research used correlation to describe the degree of relationship between results obtained by method B and other heuristics method and also for quality of our algorithm ANOVA's of output is constructed to analyse and evaluate the accuracy of the CPU time taken to determine near or optimal solution.
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吳永昌 and Wing-cheong Ng. "Assembly sequencing and Kanban assignment algorithms for just-in-time production systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31232759.
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Ng, Wing-cheong. "Assembly sequencing and Kanban assignment algorithms for just-in-time production systems /." [Hong Kong] : University of Hong Kong, 1992. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13282918.
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Tsitouras, Alexandra. "Sequencing Batch Moving Bed Biofilm Reactors for Treatment of Cheese Production Wastewater." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42126.
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Discharging cheese production wastewater with high concentrations of organics and nutrients is detrimental to receiving aquatic systems, as the release of these deleterious substances cause oxygen depletion, and eutrophication respectively. On-site treatment of cheese production wastewater requires the removal of high concentrations of organics and nutrients with a small land footprint to meet regulations. There is therefore a critical need for compact, high-rate, cost-effective wastewater technologies such a as the moving bed biofilm reactor (MBBR). Although MBBR systems have been well established for carbon and nitrogen removal, to date only a limited number of studies have achieved enhanced biological phosphorous removal in sequencing batch moving bed biofilm reactor (SB-MBBR) systems, and only for municipal-strength wastewater. Operating SB-MBBR systems under sequencing batch mode enables the reactor operation to be well synced to the fluctuating influent concentrations and flow characteristics of cheese production wastewaters. Furthermore, cycling between anaerobic and aerobic conditions can be achieved in a single sequencing batch reactor, which can promote the proliferation of poly-phosphate accumulating organisms. The SB-MBBR is studied in this research for the removal of carbon, nitrogen, and phosphorous from cheese production wastewaters. Specifically, the effects of anaerobic staging time, aeration rate, enhanced aerobic operation, and adding a second reactor in series was studied by analyzing the kinetics, biofilm characteristics, and microbiome. Extending the anaerobic staging time was shown to achieve aerobic soluble chemical oxygen demand removal rates of 92.5±2.8 g·m⁻²d⁻¹, by selecting for a thinner biofilm with, with a lower biofilm dry-density and a more rough biofilm surface, and therefore likely a biofilm with an enhanced mass transport. A significant shift in the microbiome was observed with longer anaerobic staging times and lower aeration, whereby possible putative poly-phosphate accumulating organisms including Brachymonas, and Dechloromonas were selected for in greater relative abundances compared to anaerobic bacteria. The total phosphorous removal in the possibly resulted from enhanced biological phosphorous removal, supported by the high abundance of putative poly-phosphate accumulating organisms (43.1±8.4%), which dominated the biofilms in the SB-MBBRs with 120 and 168 minute anaerobic staging times. Finally, total ammonia nitrogen oxidation was achieved through partial nitritation with a two reactor in series configuration with a removal rate of 1.07±0.05 g-N·m⁻²d⁻¹. Two SB-MBBRs operated in series was shown to be the superior strategy for achieving TAN compared to a single SB-MBBR with extended aerobic operation. By operating two SB-MBBRs in series, competition between autotrophic nitrifiers and heterotrophs is averted, and AOB proliferate in the biofilm, achieving TAN oxidation. Since TAN oxidation is likely achieved through partial nitrification, the SB-MBBR technology may be incorporated in a deammonification treatment train. The overall study presents novel information for the SB-MBBR design and operation, along with biofilm and microbiome fundamental findings that will guide future pilot- and full-scale applications of the SB-MBBR to treat cheese production wastewater.
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Färber, Gerrit. "Sequencing in Mixed Model Non-Permutation Flowshop Production Lines using Constrained Buffers." Doctoral thesis, Universitat Politècnica de Catalunya, 2007. http://hdl.handle.net/10803/5946.
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En una línea de producción clásica, solamente se producían productos con las mismas opciones. Para la fabricación de variaciones del mismo producto básico se utilizaba una línea diferente o eran necesarias modificaciones importantes de la maquinaria. En los últimos años se ha visto acrecentada la necesidad de considerar métodos que permitan más flexibilidad ofreciendo una mayor variedad de productos al cliente. En general estos métodos consisten en producir diferentes tipos de productos en una misma línea de producción. Además, con la filosofía de Just-In-Time, los stocks y sus costes derivados, especialmente el stock de productos acabados, se reducen considerablemente y consecuentemente una producción con lotes ya no es favorable. Con este panorama la producción de distintos productos o modelos en la misma línea de forma simultánea, sin lotes, adquiere un gran auge y con ello la complejidad de gestión de la línea aumenta. La toma de decisiones en las fases de secuenciación y programación se convierte en esencial.Existen varios diseños de líneas que pueden permitir la resecuenciación, como son:
utilizar grandes almacenes (Automatic-Storage-and-Retrieval-System), desacoplar una parte del proceso del resto de la línea; disponer de almacenes con plazas limitadas fuera de la línea; existencia de líneas híbridas o flexibles; posibilitar la división y unión de líneas;
o cambiar los atributos de las piezas en vez de cambiar la posición en la secuencia. La resecuenciación de piezas dentro de la línea llega ser más efectiva cuando se presenta un tiempo o coste adicional, conocido como setup-time y setup-cost, necesario en muchos casos, cuando en una estación, la siguiente pieza es de otro modelo.
Esta tesis considera el caso de una línea de flujo con la posibilidad de resecuenciar piezas entre estaciones consecutivas. Los almacenes están ubicados fuera de la línea y en un primer paso accesible desde una sola estación (caso del almacén intermedio). A continuación se utilizará un solo almacén, centralizado, accesible desde varias estaciones. En ambos casos se considera que una pieza, debido a su tamaño, quizás no pueda ocupar ciertas plazas del almacén ya sea intermedio o centralizado. Como resultado del estudio y análisis del Estado del Arte, que permitió delimitar el caso a estudiar, se propone una Novedosa Clasificación de líneas de flujo no permutación. Esta clasificación era indispensable, debido a que en la literatura actual no se ha clasificado con profundidad este tipo de producción, hasta hoy las clasificaciones existentes no consideran las múltiples opciones que se presentan al incluir la posibilidad de resecuenciar piezas en la línea. La presente tesis presenta distintas formulaciones: un método exacto, utilizando un modelo de programación por restricciones (CLP), varios métodos híbridos, basados en CLP, y un método heurístico, utilizando un Algoritmo Genético (GA).
Durante el curso de este trabajo, los estudios que se han realizado muestran la efectividad de resecuenciar. Los resultados de los experimentos simulados muestran los beneficios que sumergen con un almacén centralizado, comparado con los almacenes intermedios.
El problema considerado es relevante para una variedad de aplicaciones de líneas de flujo como es el caso de la industria química, donde los pedidos de los clientes tienen diferentes volúmenes y en la misma línea existen tanques de diferentes volúmenes para resecuenciar. También, en líneas en las cuales se utilizan lotes divididos (split-lot) con el fin de investigar variaciones en los procesos, así como en la industria de semiconductores, o en la producción de casas prefabricadas, donde fabrican paredes
grandes y pequeñas que pasan por estaciones consecutivas y en las que se instalan circuitos eléctricos, tuberías, puertas, ventanas y aislamientos.
In the classical production line, only products with the same options were processed at once. Products of different models, providing distinct options, were either processed on a different line or major equipment modifications were necessary. For today's production lines approaches, considering more flexibility, are required which result more and more in the necessity of manufacturing a variety of different models on the same line, motivated by offering a larger variety of products to the client. Furthermore, with the Just-In-Time philosophy, the stock and with that the expenses derived from it, especially for finished products, are considerably reduced and lead to the case in which a production with batches is no longer favourable.
Taking into account this panorama, the simultaneous production of distinct products or
models in the same line, without batches, lead to an increased importance and at the same time the logistic complexity enlarges. The decision-making in sequencing and scheduling become essential.
Various designs of production lines exist which permit resequencing of jobs within the production line: using large buffers (Automatic-Storage-and-Retrieval-System) which decouple one part of the line from the rest of the line; buffers which are located offline; hybrid or flexible lines; and more seldom, the interchange of job attributes instead of physically changing the position of a job within the sequence. Resequencing of jobs within the line is even more relevant with the existence of an additional cost or time, occurring when at a station the succeeding job is of another model, known as setup cost and setup time.
The present thesis considers a flowshop with the possibility to resequence jobs between consecutive stations. The buffers are located offline either accessible from a single station (intermediate case) or from various stations (centralized case). In both cases, it is considered that a job may not be able to be stored in a buffer place, due to its extended physical size.
Following the extensive State-of-the-Art, which led to the problem under study, a Novel Classification of Non-permutation Flowshops is proposed. This classification was indispensable, due to the lack of an adequate classification for flowshop production lines that would consider the diversity of arrangements which permit resequencing of jobs within the production line. Furthermore, distinct formulations are presented: an exact approach, utilizing Constrained Logic Programming (CLP), various hybrid approaches, based on CLP, and a heuristic approach, utilizing a Genetic Algorithm (GA).
During the course of this work, the realized studies of performance demonstrate the effectiveness of resequencing. The results of the simulation experiments reveal the benefits that come with a centralized buffer location, compared to the intermediate buffer location.
The considered problem is relevant to various flowshop applications such as chemical productions dealing with client orders of different volumes and different sized resequencing tanks. Also in productions where split-lots are used for engineering purpose, such as the semiconductor industry. Even in the production of prefabricated houses with, e.g., large and small walls passing through consecutive stations where electrical circuits, sewerage, doors, windows and isolation are applied.
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陳頌富 and Chung-fu Leslie Chan. "Machining process selection and sequencing under conditions of uncertainty." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31214927.
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Jonsson, Hanna, and Emmy Sjöström. "Optimization of the Cab Production Sequence : A simulation-based study at Volvo Group Trucks' cab plant in Umeå." Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-123343.
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Volvo Group’s cab plant in Umeå produces cab bodies and consists of three operating areas; the Stamping and parts production, the Body in White and the Paint shop. Today the plant produces around XXX cabs/week, but the goal is to reach the invested capacity of XXX cabs/week. In order to increase the production capacity, the efficiency of both the manual and the automated processes need to be improved. Unlike the manual processes in where the capacity can be increased by enlarged workforce, the automated processes need to be optimized. Today the cabs are produced in the same order as the orders are received. The cab plant wants to investigate if the capacity of the automated segment in the Body in White unit can be increased by changing the order in the production sequence. This culminates in the following problem definition: Is there untapped potential of the Body in White that can be achieved by an optimization of the production sequence? If so, how can Volvo Group’s cab plant in Umeå utilize this knowledge in the production planning process? The objective of the project was achieved by combining discrete event simulation with a heuristic optimization approach. The results shows that long batches in the production sequence limit the throughput of the system. By spreading the unfavorable subsequences of batches evenly over the production sequence, the total throughput of the Body in White can be increased by 52 cabs/week.Volvokoncernens hyttfabrik i Umeå producerar förarhytter och är uppdelad i tre driftsområden; pressning och detaljtillverkning, hyttsammansättning och ytbehandling. Idag producerar fabriken ca XXX hytter/vecka, men möjlighet finns att nå upp till den investerade kapaciteten på XXX hytter/vecka. För att kunna öka produktionskapaciteten behöver både de manuella och de automatiserade processerna effektiviseras. Till skillnad från de manuella processerna, där kapaciteten kan ökas genom att öka antalet operatörer, behöver de automatiserade processerna optimeras. Idag produceras hytterna i samma ordning som beställningarna kommer in. Hyttfabriken vill undersöka om det finns en möjlighet att öka kapaciteten för den automatiserade processen i Body in White genom att optimera produktionssekvensen. Detta leder fram till följande problemformulering: Finns det outnyttjad potential i Body in White som kan uppnås genom att optimera produktionssekvensen? Hur kan Volvokoncernens hyttfabrik i Umeå utnyttja denna kunskap vid planering av produktionen? Målet med projektet har uppnåtts genom att kombinera diskret händelsesimulering med optimering genom heuristiker. Resultatet visar att stora batcher av samma variant i produktionen begränsar genomströmningen i processen. Genom att bland annat sprida ut de ogynnsamma delsekvenserna jämnt över produktionssekvensen kan den totala genomströmningen i Body in White ökas med 52 hytter/vecka.
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Malicka, Aleksandra. "The Role of Task Complexity and Task Sequencing in L2 Monologic Oral Production." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/285587.
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In the domain of task-based language teaching (TBLT), researchers have long been interested in exploring the impact of internal task features and conditions on a range of outcomes, such as the occurrence and frequency of conversational episodes (between-participant interaction), interlanguage variation at a particular point in time (performance), and interlanguage transformation over time (development). In the cognitive strand of TBLT explorations, most of the theorizing, and subsequent empirical work, have been guided by the notion of cognitive task complexity, and two particularly influential frameworks have been the Trade-off Hypothesis (Skehan, 1996a, 1998) and the Cognition Hypothesis (Robinson, 2001, 2003). An area which received particular interest from researchers has been determining whether universal task design features exist which systematically influence learners’ interlanguage in predictable ways. However, most research carried to date has focused solely on the impact of task complexity by employing a dichotomy of hypothetically simple and complex tasks, rather than a sequence of tasks. Moreover, in the TBLT domain the role of individual differences, for example L2 proficiency, has been a largely underrepresented construct in both conceptual and empirical work.
Given this state of affairs, the objective of the current study was three-fold. First, it aimed to contribute further evidence to the role of task complexity on performance, as measured by general and specific fluency, complexity, and accuracy measures. Second, by employing three tasks of different cognitive complexity levels, rather than a dichotomy, it set out to explore short-term effects of simple-complex task sequencing. Third, it enquired about the role of L2 proficiency by investigating the production of two groups of participants at different stages of competence, as identified through a placement test.
In order to address the aforementioned issues, three tasks of different cognitive complexity levels were developed, identified through Needs Analysis (Long, 2005, 2006), and validated by means of participants’ subjective ratings. Cognitive complexity in these tasks was manipulated along two variables form Robinson’s (2005, 2007) Triadic Componential Framework: ±number of elements,
and ±reasoning demands. The participants in the study (N=117), were divided into three groups: 1) simple—complex sequencing (N=30), 2) randomized sequencing (N=30), and 3) individual task performance, in which different speakers performed
the tasks in its simple, complex, and very complex condition (N=18, N=19, and N=20, respectively). In the sequencing groups, half of the participants were classified as “low proficiency” and half as “high proficiency”.
The results of the dissertation have contributed further evidence to the role of cognitive task complexity on performance, with accuracy and lexical complexity being the areas which have shown an increase when task demands were high. The findings revealed a potential role of simple-complex sequencing in promoting more target-like output, but at the same time it was demonstrated that tasks performed in alternative orders presented advantages in other areas of performance: speech rate and lexical complexity. Regarding proficiency, while high proficiency speakers took advantage of increases in cognitive complexity in terms of accuracy, low proficiency speakers did so at the level of structural complexity. The findings obtained were discussed in light of the theoretical task complexity and sequencing models which have guided this work, as well as in light of speech production attention allocation models, and where possible, they were contextualized in light of previous work.En el área de la enseñanza basada en tareas pedagógicas (TBLT), los investigadores se han interesado por el impacto de las características internas de las tareas sobre la interacción entre los aprendices, la producción en la segunda lengua, y la adquisición. En la línea cognitiva, la investigación conceptual y empírica ha sido guiada por la idea de la complejidad cognitiva de las tareas, Trade-off Hypothesis (Skehan, 1996a, 1998) y Cognition Hypothesis (Robinson, 2001, 2003) siendo los marcos teóricos particularmente influyentes. Una parte substancial de las investigaciones se ha centrado en determinar si existen características universales en el diseño de las tareas que influyen en la interlengua de manera sistemática. Sin embargo, la mayoría de los estudios realizados hasta ahora han investigado el impacto de la complejidad cognitiva en dos tareas diseñadas como simples y complejas, es decir, una dicotomía, y no una secuencia de tareas. Además, en el área de TBLT el papel de las diferencias individuales, tales como la proficiencia en la segunda lengua, no ha recibido suficiente atención tanto en la investigación teórica como en la empírica. El objetivo del presente estudio es llenar estos huecos investigando la producción moderada por la complejidad cognitiva de la tarea, la secuenciación de las tareas, y la proficiencia en la segunda lengua. Se desarrolló una secuencia de tres tareas, cuya complejidad cognitiva fue manipulada a través de dos variables de Triadic Componential Framework (Robinson, 2005, 2007): ±número de elementos y ±razonamiento. Los participantes en el presente estudio (N=117) fueron divididos en tres grupos: secuenciación de simple a compleja (N=30), secuenciación aleatoria (N=30), y 3) producción individual de tareas, en la cual diferentes participantes realizaron las tareas en su condición simple, compleja, y muy compleja (N=18, N=19, y N=20, respectivamente). En los grupos que realizaron secuencias de tareas, la mitad de los participantes fueron clasificados como de “proficiencia baja” y la otra mitad como de “proficiencia alta”. Se demostró que el aumento cognitivo llevó a más precisión y complejidad lingüística, lo cual confirma los resultados de la investigación previa. Los resultados también revelaron un posible papel de la secuenciación de simple a compleja en promover la precisión lingüística. En cuanto al efecto de la proficiencia, mientras que la complejidad cognitiva benefició a los participantes de proficiencia alta en el área de la precisión lingüística, en el otro grupo fue el caso en el área de complejidad estructural.
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Hakim, Maniza Iqbal. "Identification of the gene involved in holomycin production and gene sequencing of stremptomyces cluvuligerus." Thesis, University of Strathclyde, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502279.
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Holomycin is a poor antibiotic (Oliva et al, 2001) that is made in reasonable quantities by S. clavuligerus - which is better known for production of clavulanic acid, a component of the successful clinical drug, Augmentin. Holomycin is a wasteful metabolite in the context of commercial clavulanic acid production, and mutants that no longer make holomycin have increased clavulanic acid productivity, Likewise, mutants that no longer make clavulanic acid will over-produce holomycin (de la Fuente et al, 2002). The biosynthesis of holomycin has not been studied.
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Henninger, John Thomas. "PRODUCTION SEQUENCING AND STABILITY ANALYSIS OF A JUST-IN-TIME SYSTEM WITH SEQUENCE DEPENDENT SETUPS." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_diss/764.
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Just-In-Time (JIT) production systems is a popular area for researchers but real-world issues such as sequence dependent setups are often overlooked. This research investigates an approach for determining stability and an approach for mixed product sequencing in production systems with sequence dependent setups and buffer thresholds which signal replenishment of a given buffer. Production systems in this research operate under JIT pull production principles by producing only when demand exists and idle when no demand exists.
In the first approach, an iterative method is presented to determine stability for a multi-product production system that operates with replenishment signals and may have sequence dependent setups. In this method, a network of nodes representing machine states and arcs representing the buffer inventory levels is used to find a stable trajectory for the production system via an iterative procedure. The method determines suitable buffer levels for the production system that ensure that a trajectory originating from any point within a buffer region will always map to a point contained on another buffer region for all future mappings.
This iterative method for determining the stability of a production system was implemented using an algorithm to calculate the buffer inventory regions for all arcs in a given arc-node network. The algorithm showed favorable results for two and three product systems in which sequence dependent setups may exist.
In the second approach, a product sequencing algorithm determines a product sequence for a production system based on system parameters – setup times, buffer levels, usage rates, production rates, etc. The algorithm selects a product by evaluating the goodness of each product that has reached the replenishment threshold at the current time. The algorithm also incorporates a lookahead function that calculates the goodness for some time interval into the future. The lookahead function considers all branches of the tree of potential sequences to prevent the sequence from travelling down a dead-end branch in which the system will be unable to avoid a depleted buffer. The sequencing algorithm allows the user to weight the five terms of the goodness equations (current and lookahead) to control the behavior of the sequence.
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Farias, Ana Beatriz Gentil de. "Hybrid flow shop production systems with explicit machine setup times and continuous job processing." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14892.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorThe study deals with the problems of Production Scheduling in Flow Shop environment with multiple machines in the production stages, where the setup time is not inserted in the processing time of the operations. May be a production system in which the setup depends on whether or not the sequence of tasks, where tasks are performed without interruption between successive operations, also called production system no-wait. Being proposed in this work, twenty methods of heuristic solutions defined by Priority Rules, which provide an ordering of the tasks to be followed in its programming, which is done each task, successively. Twenty of these proposed heuristics, seven were implemented for the case of set operations independent of the sequence of tasks, and thirteen dependent heuristics tested for setup. To perform the computational experience we developed a specific software. For evaluation of the software generated a set of thirty-six thousand test-problems that are differentiated according to the number of tasks (n), number of production stages (g), levels of flexibility (f) and time intervals of setup (s). Following the result of these problems-tests are evaluated by some statistical measures.
O estudo trata dos problemas de ProgramaÃÃo da ProduÃÃo em ambiente Flow Shop com mÃquinas mÃltiplas nos estÃgios de produÃÃo, nos quais o tempo de setup nÃo està inserido no tempo de processamento das operaÃÃes. Podendo ser um sistema produtivo em que o setup depende ou nÃo da sequÃncia das tarefas, nos quais as tarefas sÃo realizadas sem interrupÃÃo entre operaÃÃes sucessivas, tambÃm chamado sistema de produÃÃo no-wait. Sendo proposto neste trabalho, vinte mÃtodos de soluÃÃes heurÃsticas definidos por Regras de Prioridade, as quais fornecem uma ordenaÃÃo das tarefas a ser seguida na sua programaÃÃo, que à feita tarefa por tarefa, sucessivamente. Destas vinte heurÃsticas propostas, sete foram implementadas para o caso de setupindependente da sequÃncia de operaÃÃes das tarefas, e treze heurÃsticas testadas para setup dependente. Para a realizaÃÃo da experimentaÃÃo computacional foi desenvolvido um software especÃfico. Para avaliaÃÃo do software foi gerado um conjunto de trinta e dois mil problemas-teste que sÃo diferenciados em funÃÃo do nÃmero de tarefas (n), nÃmero de estÃgios de produÃÃo (g), nÃveis de flexibilidade (f) e intervalos de tempo de setup (s). Na sequÃncia o resultado destes problemas-testes sÃo avaliados por algumas medidas estatÃsticas.
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Han, Yong-Hee. "Dynamic Sequencing of Jobs on Conveyor Systems for Minimizing Changeovers." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4877.
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This research investigates the problem of constrained sequencing of a set of jobs on a conveyor system with the objective of minimizing setup cost. A setup cost is associated with extra material, labor, or energy required due to the change of attributes in consecutive jobs at processing stations. A finite set of attributes is considered in this research. Sequencing is constrained by the availability of two elements ??orage buffers and conveyor junctions. The problem is motivated by the paint purge reduction problem at a major U.S. automotive manufacturer. First, a diverging junction with a sequence-independent setup cost and predefined attributes is modeled as an assignment problem and this model is extended by relaxing the initial assumptions in various ways. We also model the constrained sequencing problem with an off-line buffer and develop heuristics for efficiently getting a good quality solution by exploiting the special problem structure. Finally, we conduct sensitivity analysis using numerical experiments, explain the case study, and discuss the use of the simulation model as a supplementary tool for analyzing the constrained sequencing problem.
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Reynolds, Derrick James. "Genetic Dissection of Triterpenoid Saponin Production in Chenopodium quinoa Using Microarray Analysis." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3309.pdf.
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Sarma, Mimosa. "Microfluidic platforms for Transcriptomics and Epigenomics." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/90294.
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A cell, the building block of all life, stores a plethora of information in its genome, epigenome, and transcriptome which needs to be analyzed via various Omic studies. The heterogeneity in a seemingly similar group of cells is an important factor to consider and it could lead us to better understand processes such as cancer development and resistance to treatment, fetal development, and immune response. There is an ever growing demand to be able to develop more sensitive, accurate and robust ways to study Omic information and to analyze subtle biological variation between samples even with limited starting material obtained from a single cell. Microfluidics has opened up new and exciting possibilities that have revolutionized how we study and manipulate the contents of the cell like the DNA, RNA, proteins, etc. Microfluidics in conjunction with Next Gen Sequencing has provided ground-breaking capabilities for handling small sample volumes and has also provided scope for automation and multiplexing. In this thesis, we discuss a number of platforms for developing low-input or single cell Omic technologies. The first part talks about the development of a novel microfluidic platform to carry out single-cell RNA-sequencing in a one-pot method with a diffusion-based reagent swapping scheme. This platform helps to overcome the limitations of conventional microfluidic RNA seq methods reported in literature that use complicated multiple-chambered devices. It also provides good quality data that is comparable to state-of-the-art scRNA-seq methods while implementing a simpler device design that permits multiplexing. The second part talks about studying the transcriptome of innate leukocytes treated with varying levels of LPS and using RNA-seq to observe how innate immune cells undergo epigenetic reprogramming to develop phenotypes of memory cells. The third part discusses a low-cost alternative to produce tn5 enzyme which low-cost NGS studies. And finally, we discuss a microfluidic approach to carrying out low-input epigenomic studies for studying transcription factors. Today, single-cell or low-input Omic studies are rapidly moving into the clinical setting to enable studies of patient samples for personalized medicine. Our approaches and platforms will no doubt be important for transcriptomic and epigenomic studies of scarce cell samples under such settings.Doctor of Philosophy
This is the era of personalized medicine which means that we are no longer looking at one-size-fits-all therapies. We are rather focused on finding therapies that are tailormade to every individual’s personal needs. This has become more and more essential in the context of serious diseases like cancer where therapies have a lot of side-effects. To provide tailor-made therapy to patients, it is important to know how each patient is different from another. This difference can be found from studying how the individual is unique or different at the cellular level i.e. by looking into the contents of the cell like DNA, RNA, and chromatin. In this thesis, we discussed a number of projects which we can contribute to advancement in this field of personalized medicine. Our first project, MID-RNA-seq offers a new platform for studying the information contained in the RNA of a single cell. This platform has enough potential to be scaled up and automated into an excellent platform for studying the RNA of rare or limited patient samples. The second project discussed in this thesis involves studying the RNA of innate immune cells which defend our bodies against pathogens. The RNA data that we have unearthed in this project provides an immense scope for understanding innate immunity. This data provides our biologist collaborators the scope to test various pathways in innate immune cells and their roles in innate immune modulation. Our third project discusses a method to produce an enzyme called ‘Tn5’ which is necessary for studying the sequence of DNA. This enzyme which is commercially available has a very high cost associated with it but because we produced it in the lab, we were able to greatly reduce costs. The fourth project discussed involves the study of chromatin structure in cells and enables us to understand how our lifestyle choices change the expression or repression of genes in the cell, a study called epigenetics. The findings of this study would enable us to study epigenomic profiles from limited patient samples. Overall, our projects have enabled us to understand the information from cells especially when we have limited cell numbers. Once we have all this information we can compare how each patient is different from others. The future brings us closer to putting this into clinical practice and assigning different therapies to patients based on such data.
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Raffan, Eleanor. "Rare syndromes of perturbed insulin action and production : application of exome sequencing and characterisation of their cellular phenotypes." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648236.
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Johansson, My Ngoc, and Hasbani Salwa Al. "Minimization of Output Variation in Mass Customized Production." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-38410.
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During the past decades, there have been an acceleration of customers’ needs of customized products. This have pressured many companies in offering customized products in order to reach customer satisfaction and keep growing and expanding their market share. Nowadays the competitive pressure between companies with the same product segment is increasing and the market requirements are changing rapidly. To handle this competition, many manufacturing companies are focusing on mass customized production. However, mass customization has been a topic of interest for many researchers. The focus has been in studying and understanding the complexity and the constrains that a company encounter when dealing with mass customized production in mostly the automotive industry. One of the constrains that have been less highlighted by researchers were the effects that mass customized production has on the output variation of production lines. Therefore, the purpose of this thesis is to investigate how to minimize output variations in mass customized production within assembly lines. To do that the researchers focused on studying the output variation in whitegoods industry instead of the automotive industry that captures most of the existing research. The study includes two main research questions. The first question was to identify the factors that affect the output variation in mass customized production. While the second question was to identify applicable solutions that can be used to stabilize the output. To ensure the reliability and validity of the research findings, the researchers used multiple case study combined with literature reviews. To answer the research questions several data collection techniques were used in the multiple case study conducted on two lines. Those data collection techniques were participating observations, document reviews, a semi-structured interview and many conversations with the affected persons. The findings from the case study for research question one showed consistency with the theories described in the theoretical background. This was evident because similar problems when it comes to output variations were defined in the theories. One problem was about the simplification of assembly line balancing problem that was evident in both case studies. This was an effect of the missing product family classification which created a high output variation because of the use of only one line balancing for all product variants. Another problem identified included functionality problems of machines because of performing wrong assembly or the use of the wrong component. There was as well the problem of missing or delayed components which was an effect of the lack of structure in the material picking and the deliveries performed for both lines. A combination of those factors created the experienced output variation on both lines. To deal with those problems and minimize the output variation, a solution approach was defined in the second research question. This approach was created together with the case company with the help of the theoretical background and it presents several steps to follow when attacking and resolving similar problems as presented above. The most important conclusion of this thesis is that, when dealing with output variation in mass customized production where people are performing the assembly, it is essential to provide the right conditions for them to ensure that they have the right knowledge base to perform the requested assembly.
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Kircher, Martin [Verfasser], Janet [Akademischer Betreuer] Kelso, Anton [Gutachter] Nekrutenko, and Peter F. [Gutachter] Stadler. "Understanding and improving high-throughput sequencing data production and analysis / Martin Kircher ; Gutachter: Anton Nekrutenko, Peter F. Stadler ; Betreuer: Janet Kelso." Leipzig : Universitätsbibliothek Leipzig, 2011. http://d-nb.info/1237894654/34.
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Moussavi, Seyed Esmaeil. "Workforce scheduling and job rotation by considering ergonomic factors (Presentation of the Sequencing Generalized Assignment Problem) : application to production and home healthcare systems." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCA017/document.
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Cette thèse porte sur la planification du personnel en accordant une attention particulière à l'aspect humain et aux facteurs ergonomiques dans le domaine de la production. Un certain nombre de modèles mathématiques sont présentés pour formuler les problèmes d'ordonnancement et de planification du personnel étudié. Concernant les modèles de planification, la productivité du système de fabrication et le bien-être des travailleurs sont ciblés. De cette manière, une méthode d'affectation des travailleurs est présentée pour réduire le temps de production et une méthode d'ordonnancement pour la rotation des tâches est présentée afin d’équilibrer la charge de travail des opérateurs. À cet effet, une analyse ergonomique est effectuée sur les postes de travail du système de production étudié. Cette analyse aboutit à l'évaluation des postes du travail suivant la convention dite des feux de circulation, c'est-à-dire que les postes sont classés dans les niveaux de charge faible, moyen et élevé qui sont représentés respectivement par les couleurs verte, jaune et rouge. Une approche mathématique est développée pour convertir ces résultats en valeurs numériques, car les paramètres quantitatifs sont plus applicables pour l'optimisation de la planification. Une programmation multi-objectifs est proposée pour optimiser les deux objectifs mentionnés du problème d'ordonnancement de tournée du personnel étudié. Les méthodes d'agrégation linéaire et de ε-contrainte sont appliquées pour résoudre ce modèle d'optimisation. En outre, cette thèse présente une nouvelle variante du problème d'affectation appelé problème d'affectation généralisée par séquence qui est défini pour la planification du personnel dans un système combiné constitué des postes de travail en série et en parallèle. Il est prouvé que ce problème d'optimisation combinatoire est NP-difficile et les méthodes exactes ne sont pas capables de résoudre les instances de grande taille. Ainsi, trois méthodes approchées composées de deux approches matheuristiques et une heuristique hybride sont développées pour résoudre ce problème. Les méthodes matheuristiques sont basées sur la décomposition de la formulation pour simplifier le modèle principal en deux ou plusieurs modèles plus petits. La troisième méthode est une heuristique gloutonne combinée à une recherche locale. En outre, dans la dernière étape de cette thèse, la planification des ressources humaines pour un système de soins à domicile est formulée mathématiquement. Selon la structure du système, une intégration des problèmes d'affectation et de tournées de véhicules est présentée. Enfin, une approche matheuristique en trois étapes est proposée pour résoudre ce problème d'optimisation combinatoireThis thesis concerns the human resource planning by paying a special attention to the human aspect and ergonomic factors in the manufacturing domain. A number of mathematical models are presented to formulate the studied workforce scheduling and planning problems. In the planning models, the productivity of the manufacturing system and the well-being of the workers are targeted. In this way, a worker assignment approach is presented to reduce the production time and a job rotation scheduling approach is presented to balance the workloads on the operators. For this purpose, an ergonomic analysis is carried out on the jobs of the studied production system. This analysis results in the traffic light evaluation for the jobs, i.e., the jobs are categorized into the low, medium and high workload levels which are presented respectively by the green, yellow and red colors. A mathematical approach is developed to convert these outputs to the numerical values, because the quantitative parameters are more applicable for the optimization of the planning. A multi-objective programming is proposed to optimize two mentioned objectives of the studied workforce scheduling problem. Both linear aggregation and epsilon-constraint methods are applied to solve this optimization model. Furthermore, this thesis presents a novel variant of the assignment problem called sequencing generalized assignment problem which is defined for workforce scheduling in a combined system consisting of the jobs in series and in parallel. It is proved that this combinatorial optimization problem is NP-hard and the exact methods are not able to solve the large-scale instances. Hence, three approximate methods consisting of two matheuristic and a hybrid heuristic approaches are developed to solve it. The matheuristic methods are based on the decomposition of the formulation to break down and simplify the main model into two or more smaller models. The third method is a greedy heuristic combined with a local search. The efficiency of the three mentioned methods is evaluated by various instances of different sizes. Moreover, in the last step of this thesis, the human resource planning for a home healthcare system is formulated mathematically. According to the structure of the system, an integration of the worker assignment and vehicle routing problems is presented. Finally, a three-steps matheuristic approach is proposed to solve this combinatorial optimization problem
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Marmontel, Oriane. "Dysrégulations de la production et de la clairance des lipoprotéines riches en triglycérides." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1220/document.
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L’hypertriglycéridémie (HTG) correspond à une accumulation des lipoprotéines riches en triglycérides (LRTG) dans la circulation plasmatique, conséquence d’une augmentation de leur synthèse ou plus classiquement décrit, d’une diminution de leur catabolisme. Dans près de 50% des cas, aucune cause génétique n’est identifiée chez les patients présentant une présentant une HTG sévère, aussi bien dans le cadre du syndrome de chylomicronémie familiale (FCS) que dans celui du syndrome de chylomicronémie multifactorielle (MCS). Pour améliorer nos connaissances et la caractérisation de ces patients, la conduction de corrélations phénotypes-génotypes précises grâce à une collaboration clinico-biologique étroite, ainsi que le développement d’outils de diagnostic moléculaire performants, demeurent un enjeu majeur. Premièrement, l’évaluation de la concentration pré-héparinique en LPL et l’activité post-héparinique 60 minutes après l’injection d’héparine chez 62 patients MCS caractérises génétiquement a permis la mise en évidence deux sous-groupes chez ces patients. Deuxièmement, le développement d’une stratégie séquençage de nouvelle génération permettant d’explorer simultanément les 9 gènes les plus prévalents dans les hypercholestérolémies, les hypocholestérolémies et les hypertriglycéridémies, a permis de détecter les variants nucléotidiques avec une sensibilité équivalente au séquençage Sanger mais aussi de détecter des grands réarrangements. L’ensemble des résultats souligne la complexité des mécanismes de régulation du métabolisme des LRTG et l’intérêt de l’étude des interactions gène-gène. Ainsi, ces travaux ont permis de mettre en évidence de nouvelles hypothèses à explorer pour la compréhension des mécanismes physiopathologiques des HTG sévères et d’améliorer les outils disponibles pour les études de corrélation génotype-phénotypeHypertriglyceridemia (HTG) correspond to an increase of triglyceride-rich lipoproteins (TGRL) circulating concentration, as a consequence of an increase in the synthesis of or a decrease in their catabolism, most classically described. In nearly 50% of patients with severe hypertriglyceridemia (HTG), no genetic cause is identified, either in familial chylomicronemia syndrome (FCS) or in multifactorial chylomicronemia syndrome (MCS). To gain new insights and to improve patient’s characterization, it remains important to conduct accurate phenotype-genotype association studies through close collaboration with referent lipidologists, and to develop high-performance tools for molecular diagnosis. Firstly, the assessment of pre-heparin LPL concentration as well as LPL activity 60 minutes after heparin injection, enabled the identification of two subgroups within 62 genotyped MCS patients Secondly, the development of a new sequencing generation workflow exploring simultaneously the 9 most prevalent genes in dyslipidemia, allowed the detection of single nucleotide variations with sensitivity equivalent to Sanger sequencing, but also allowed the detection of copy number variations. Collective consideration of the results underlines the complexity of the regulation mechanisms of TGRL metabolism and the interest of gene-gene interactions study. Thus, the studies presented herein bring new hypothesis to explore for understanding the pathophysiological mechanisms of severe HTG and to improve molecular diagnosis tools available for phenotype-genotype association studies
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Meakin, Nicholas G. "Metagenomic analyses of marine new production under elevated CO2 conditions." Thesis, University of Stirling, 2009. http://hdl.handle.net/1893/1555.
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A mesocosm experiment was carried out in a Norwegian fjord near Bergen in May 2006, with the main objective being the study of the effects of increasing concentrations of atmospheric CO2 (and associated effects such as increased acidification) on blooms of natural marine coastal plankton. Three mesocosms were bubbled with CO2(g) to achieve a high (~700ppm) CO2 concentration (pH ~7.8) to simulate predicted future conditions as a result of rising atmospheric CO2 concentrations. Another three mesocosms were treated as controls and bubbled with ambient air to represent a near pre-industrial scenario (atmospheric CO2 concentration ~300ppm, surface seawater pH ~8.15). Blooms in the mesocosms were stimulated by the addition of nutrients at a near-Redfield ratio ([N:P] ≈ [16:1]), and scientific measurements and analyses were carried out over the course of the blooms for approximately one month. Of particular interest in this study were the autotrophic plankton. The diversity and activities of these microorganisms under the two treatments was therefore investigated. By designing and using new degenerate primers specifically targeting ‘Green-type’ (Form IA and IB), ‘Red-type’ (Form IC and ID) and Form II RuBisCO, analysis of primary producers was carried out using PCR and either gDNA or cDNA (mRNA) templates from key time points spanning the complete duration of the blooms throughout the mesocosm experiment. Over 1250 novel RuBisCO large subunit sequences have been fully annotated and deposited in the NCBI GenBank® database. These sequences revealed distinct changes in the diversity of primary producers both over the courses of the blooms and between treatments. Particularly striking was the effect of acidification on the community structure of the eukaryotic picoplankton, Prasinophytes. A clade of prasinophytes closely related to Micromonas pusilla showed a distinct preference for the high CO2 conditions; a laboratory-based experiment confirmed the high tolerance of Micromonas pusilla to lower pH. Conversely, a clade related to Bathycoccus prasinos was almost entirely excluded from the high CO2 treatments. Clades of form II RuBisCO-containing dinoflagellates were also abundant throughout the experiment in both treatments. The high similarity of some of these clades to the toxin-producing species Heterocapsa triquetra and Gonyaulax polyedra, and apparent high tolerance of some clades to high CO2 conditions, is perhaps cause for concern in a high CO2 world and demands further research. In parallel with the RubisCO work, new primers were designed that target the gene encoding the Fe protein of nitrogenase (NifH). 82 Bergen genomic nifH sequences have been annotated and submitted to GenBank®. These sequences include those from organisms related to Alpha, Beta, and Gammaproteobacteria, and Cluster II and Cluster III sequences that align most closely with anaerobic Bacteria, Gram positive, and/or sulphur-reducing Bacteria. The biggest surprise, however, was the apparent abundance and significance of a Rhodobacter sphaeroides-like microorganism throughout the duration of the experiment in both treatments. Whilst this clade was unsurprisingly absent in the RuBisCO cDNA libraries, all but two of 128 nifH cDNA clones analysed were identical to the gene from Rhodobacter sphaeroides. This shows that this clade was potentially fixing N2 throughout the entire experiment, even in the presence of combined N added to both sets of mesocosms at the start of the experiment. A group of Rhodobacter sphaeroides-like microorganisms present at Bergen may therefore have been an unexpected source of new N during the experiment and contributed to the maintenance of the mesocosm communities as nutrients became depleted. One organism dominated the autotrophic communities after the blooms in both treatments. Synechococcus spp. Form IA rbcL clones most closely related to the coastal strain Synechococcus sp. strain CC9902 were recovered throughout the experiment but were particularly numerous toward the end of the experiment and dominated the “Green-type” libraries at this time. Initially, rbcL clones from these cyanobacteria were mostly derived from the ambient CO2 mesocosms but were equally distributed between treatments by the end of the experiment. This suggests that cyanobacteria related to strain CC9902 may be less tolerant of elevated CO2 (which was greatest at the beginning rather than the end of the experiment). However, despite the mesocosms being Pi-limited at the end of the experiment, several Synechococcus species (including those related to strain CC9902 and another coastal strain, CC9311) thrived. Following on from this observation, Pi uptake and assimilation mechanisms in a Synechococcus species were investigated in the laboratory. This led to the sequencing and characterisation of a pstS gene from the marine cyanobacterium Synechococcus sp. WH 8103. Unlike conventional pstS, it was discovered that the pstS II gene in this organism is constitutively expressed and unresponsive to or only weakly regulated by Pi supply. The use of PstS/pstS as a marker for P-limitation in natural samples, therefore, should be interpreted with caution.
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Kalir, Adar A. "Optimal and heuristic solutions for the single and multiple batch flow shop lot streaming problems with equal sublots." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/37485.
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This research is concerned with the development of efficient solutions to various problems that arise in the flow-shop environments which utilize lot-streaming. Lot streaming is a commonly used process of splitting production lots into sublots and, then, of scheduling the sublots in an overlapping fashion on the machines, so as to expedite the progress of orders in production and to improve the overall performance of the production system.
The different lot-streaming problems that arise in various flow-shop environments have been divided into two categories, single-lot problems and multiple-lot problems. Further classification of the multiple-lot problems into the lot streaming sequencing problem (LSSP) and the flow-shop lot-streaming (FSLS) problem is made in this work. This classification is motivated by the occurrence of these problems in the industry. Several variants of these problems are addressed in this research. In agreement with numerous practical applications, we assume sublots of equal sizes. It turns out that this restriction paves the way to the relaxation of several typical limitations of current lot-streaming models, such as assumption of negligible transfer and setup times or consideration of only the makespan criterion. For the single-lot problem, a goal programming (GP) approach is utilized to solve the problem for a unified cost objective function comprising of the makespan, the mean flow time, the average work-in-process (WIP), and the setup and handling related costs. A very fast optimal solution algorithm is proposed for finding the optimal number of sublots (and, consequently, the sublot size) for this unified cost objective function in a general m-machine flow shop.
For the more complicated multiple-lot problem, a near-optimal heuristic for the solution of the LSSP is developed. This proposed heuristic procedure, referred to as the Bottleneck Minimal Idleness (BMI) heuristic, identifies and employs certain properties of the problem that are irregular in traditional flow-shop problems, particularly the fact that the sublot sizes eminating from the same lot type and their processing times (on the same machines) are identical. The BMI heuristic attempts to maximize the time buffer prior to the bottleneck machine, thereby minimizing potential bottleneck idleness, while also looking-ahead to sequence the lots with large remaining process time earlier in the schedule. A detailed experimental study is performed to show that the BMI heuristic outperforms the Fast Insertion Heuristic (the best known heuristic for flow-shop scheduling), when modified for Lot Streaming (FIHLS) and applied to the problem on hand.
For the FSLS problem, several algorithms are developed. For the two-machine FSLS problem with an identical sublot-size for all the lots, an optimal pseudo-polynomial solution algorithm is proposed. For all practical purposes (i.e., even for very large lot sizes), this algorithm is very fast. For the case in which the sublot-sizes are lot-based, optimal and heuristic procedures are developed. The heuristic procedure is developed to reduce the complexity of the optimal solution algorithm. It consists of a construction phase and an improvement phase. In the construction phase, it attempts to find a near-optimal sequence for the lots and then, in the improvement phase, given the sequence, it attempts to optimize the lot-based sublot-sizes of each of the lots. Extensions of the solution procedures are proposed for the general m-machine FSLS problem.
A comprehensive simulation study of a flow shop system under lot streaming is conducted to support the validity of the results and to demonstrate the effectiveness of the heuristic procedures. This study clearly indicates that, even in dynamic practical situations, the BMI rule, which is based on the proposed BMI heuristic, outperforms existing WIP rules, commonly used in industry, in scheduling a flow-shop that utilizes lot streaming. With respect to the primary performance measure - cycle time (or MFT) - the BMI rule demonstrates a clear improvement over other WIP rules. It is further shown that it also outperforms other WIP rules with respect to the output variability measure, another important measure in flow-shop systems. The effects of several other factors, namely system randomness, system loading, and bottleneck-related (location and number), in a flow-shop under lot streaming, are also reported.Ph. D.
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Assis, Arinéia Nogueira de. "UM ESTUDO SOBRE ESTRATÉGIAS DE PCP E SCO E UMA APLICAÇÃO DE UM MODELO PARA O SEQUENCIAMENTO DE PRODUÇÃO." Pontifícia Universidade Católica de Goiás, 2014. http://localhost:8080/tede/handle/tede/2452.
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Previous issue date: 2014-02-27The first objective of this study is to classify the production planning and control (PPC) strategy and the ordering system (OS) of a clothing company, and the second is to propose a theoretical model based on PPC strategies and production sequencing for consequent practical implementation in industries with repetitive production system and multiple products. A study case was conducted, identifying reduction and qualification in inventory, increasing productivity as results.
O primeiro objetivo deste trabalho é classificar a estratégia de planejamento e controle de produção (PCP) e o sistema de coordenação de ordens (SCO) de uma indústria de confecção. E, o segundo, é propor um modelo teórico baseado em estratégias de PCP e sequenciamento de produção, para sua consequente implantação prática em indústrias com sistema de produção repetitivo e com múltiplos produtos. Realizou-se um estudo de caso e apresentou-se os resultados, identificando redução e qualificação de estoque, e aumento da produtividade.
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Lovato, Gustavo Dias. "Alimentação sequencial para suínos e aves : efeito sobre o desempenho e metabolismo energético e proteico." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/164313.
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Dois experimentos foram realizados para avaliar o efeito da alimentação sequencial (AS) no desempenho e metabolismo energético e proteico de frangos de corte e suínos em crescimento. No primeiro experimento foram utilizados 144 frangos de corte com 21 dias de idade, alojados em baterias de metabolismo. As dietas A e B foram formuladas para atender 100% e 80% das recomendações de aminoácidos digestíveis, respectivamente. Os tratamentos utilizados foram: Tratamento AA, dieta A, fornecida durante todo o ciclo de 24 horas; Tratamento AB, dieta A fornecida durante o dia e dieta B fornecida durante a noite; Tratamento BA, dieta B fornecida durante o dia e dieta A fornecida durante a noite e; Tratamento BB, dieta B fornecida durante todo o ciclo de 24 horas. No experimento com suínos foram utilizados 16 animais com peso inicial de 30 kg, alojados em gaiolas metabólicas. Os tratamentos e as dietas experimentais seguiram as mesmas proposições do experimento com aves, porém com parâmetros nutricionais ajustados para suínos. Os frangos submetidos à AS apresentaram desempenho semelhante à dieta completa, com ligeira piora na conversão alimentar. Os frangos de corte dos tratamentos com AS ingeriram menos energia, nitrogênio (N) e lisina comparadas aos animais alimentados exclusivamente com a dieta A. Os valores de retenção e excreção de N nos frangos alimentados sob regime de AS compararam-se ao tratamento AA. O tratamento BA excretou menos N e obteve uma relação de retenção de N por quilograma de peso vivo equivalente ao tratamento AA. Em suínos, não foram detectados efeitos da AS sobre o peso final, consumo de ração diário, ganho de peso diário e conversão alimentar. A ingestão de N foi influenciada pela AS, mas não houve diferença na excreção e retenção de N, comparado ao tratamento AA. Os programas de AS apresentam desempenhos similares com reduzida ingestão de nutrientes e retenções de N similares a programas de alimentação convencionais em frangos de corte. AAS mantém o potencial de retenção de nitrogênio de uma dieta convencional, sem alterar os coeficientes de digestibilidade da dieta e o desempenho zootécnico. O fornecimento da dieta deficiente em aminoácidos durante o período da noite parece ser a melhor escolha para otimizar retenção de nitrogênio ao aplicar a estratégia de alimentação sequencial em suínos.Two experiments were carried out to evaluate the effect of sequential feeding (AS) on performance and energy and protein metabolism of broiler chickens to growing pigs. In the experiment in birds were used 144 broiler chickens with 21 days of age, housed in metabolism batteries. Diets A and B were formulated to meet 100% and 80% of digestible amino acid recommendations, respectively. The treatments utilized were: Treatment AA, diet A, provided throughout the 24-hour cycle; AB treatment, A diet provided during the day and diet B provided overnight; Treatment BA, diet B provided during the day and diet A provided at night and; Treatment BB, diet B provided throughout the 24 hour cycle. In the experiment with pigs were used 16 animals with initial weight of 30 kg, housed in metabolic cages. The treatments and the experimental diets followed the same propositions of the experiment with birds, however with nutritional parameters adjusted for pigs. The birds submitted to AS presented similar performance to the complete diet, with a slight worsening in feed conversion. The birds in the AS treatments ingested less energy, nitrogen (N) and lysine compared to birds fed exclusively on diet A. The N retention and excretion values in the birds fed under AS regimen were compared to the AA treatment. The BA treatment excreted less N and had a N retention ratio per kilogram live weight equivalent to the AA treatment. In pigs, no effects of AS and final weight, daily feed intake, daily weight gain and feed conversion were detected. N intake was influenced by AS, but there was no difference in N excretion and retention compared to AA treatment. AS programs perform similar performances with reduced nutrient intakes and N retention similar to conventional feeding programs in broilers. AS maintains the nitrogen retention potential of a conventional diet without altering the digestibility coefficients of the diet and the zootechnical performance. The supply of the amino acid deficient diet over night appears to be the best choice to optimize nitrogen retention by applying the sequential dietary strategy.
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Gottardi, Davide <1983>. "Production of bioactive peptides through sequencial action of Yarrowia lipolytica proteases and chemical glycation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5718/.
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This PhD thesis is aimed at studying the suitability of proteases realised by Yarrowia lipolytica to hydrolyse proteins of different origins available as industrial food by-products. Several strains of Y. lipolytica have been screened for the production of extracellular proteases by zymography. On the basis of the results some strains released only a protease having a MW of 37 kDa, which corresponds to the already reported acidic protease, while other produced prevalently or only a protease with a MW higher than 200 kDa. The proteases have been screened for their "cold attitude" on gelatin, gluten and skim milk. This property can be relevant from a biotechnological point of view in order to save energy consumption during industrial processes. Most of the strains used were endowed with proteolytic activity at 6 °C on all the three proteins. The proteolytic breakdown profiles of the proteins, detected at 27 °C, were different related to the specific strains of Y. lipolytica. The time course of the hydrolysis, tested on gelatin, affected the final bioactivities of the peptide mixtures produced. In particular, an increase in both the antioxidant and antimicrobial activities was detected when the protease of the strain Y. lipolytica 1IIYL4A was used. The final part of this work was focused on the improvement of the peptides bioactivities through a novel process based on the production of glycopeptides. Firstly, the main reaction parameters were optimized in a model system, secondly a more complex system, based on gluten hydrolysates, was taken into consideration to produce glycopeptides. The presence of the sugar moiety reduced the hydrophobicity of the glycopeptides, thus affecting the final antimicrobial activity which was significantly improved. The use of this procedure could be highly effective to modify peptides and can be employed to create innovative functional peptides using a mild temperature process.
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Branco, Fábio José Ceron. "Um novo método heurístico construtivo de alto desempenho para o problema noidle flow shop." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/18/18140/tde-05092011-094838/.
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Este trabalho é direcionado ao problema de Programação de Operações No-Idle Flow Shop Permutacional. Uma propriedade do problema, oriunda de estudo sobre a sua característica, é apresentada e utilizada para o desenvolvimento de um novo método heurístico construtivo, com o objetivo de minimizar a Duração Total da Programação (makespan). O novo método é comparado com os melhores heurísticos construtivos reportados na literatura, conhecidos por IG, KK e FRB3. Os resultados da experimentação computacional mostraram o melhor desempenho do método proposto, denominado BHBN, para os problemas testes de Ruiz et al. (2008) e Taillard (1993), quanto à qualidade da solução, apresentando também eficiência computacional.This work is addressed to the No-Idle Flow Shop Sequencing problem. As a result of an investigation on the problem characteristics it is presented a property of this scheduling problem, which is used for the development of a new constructive heuristic with the objective of minimizing the Total Time to complete the schedule (makespan). The new method is compared with the best constructive heuristics reported in the literature, named IG, KK and FRB3. Results from computational experience showed the best performance of the proposed method, denoted by BHBN, for the instances of Ruiz et al. (2008) and Taillard (1993), as to the quality of the solution, and also computational efficiency.
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Gonçalves, Juliano Leonel. "Produção e composição do leite de vacas com mastite causada por Corynebacterium spp." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-07062013-112423/.
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A mastite é a inflamação da glândula mamária cuja causa mais comum são as infecções bacterianas. É considerada a doença de maiores prejuízos e prevalência em vacas leiteiras. A forma subclínica da mastite é o tipo mais predominante de infecção intramamária (IIM), sendo Corynebacterium spp. um dos agentes mais frequentemente isolados. Portanto, os objetivos gerais deste estudo foram: 1) avaliar o efeito de IIMs subclínicas causadas por Corynebacterium spp. sobre a composição e a produção de leite de quartos mamários; 2) determinar o efeito da IIM causada por Corynebacterium spp. sobre o teor de gordura, proteína bruta, lactose, caseína, extrato seco total, extrato seco desengordurado do leite e contagem de células somáticas (CCS); 3) avaliar a técnica de Espectrometria de massas por Ionização e Dessorção à Laser Assistida por Matriz Tempo de Voo (MALDI/TOF-MS) para a identificação das espécies de Corynebacterium isoladas de quartos mamários. Foram utilizados 21 rebanhos leiteiros (n=1.242 animais), nos quais foram selecionadas vacas em lactação previamente identificadas com IIM causada por Corynebacterium spp. (n=285). Amostras de leite de quartos mamários de vacas previamente identificadas com IIM causada por Corynebacterium spp. (n=1.140) foram coletadas, identificadas por meio de cultura microbiológica e criopreservadas. Os isolados de Corynebacterium spp. (n=351) foram descongelados, recultivados e submetidos à identificação pela técnica de sequenciamento de genes 16S rRNA (standard gold) e MALDI/TOF-MS. Para a análise de MALDI/TOF-MS, os isolados bacterianos foram submetidos a protocolo de extração em tubo, baseado no uso de ácido fórmico. Do total de quartos mamários infectados por Corynebacterium spp. (n=190) identificados pelo sequenciamento de genes 16S rRNA, 46 quartos mamários apresentaram contralaterais sadios (controle). Para a coleta de amostras de leite para composição e CCS, as vacas foram submetidas à ordenha completa e individual dos quartos mamários. Foi avaliado o efeito de IIM causada por Corynebacterium spp. sobre a produção e a composição do leite, utilizando delineamento em parcelas subdivididas em faixas (strip-plot). Todos os quartos mamários infectados por Corynebacterium spp. (n=190) apresentaram média de CCS de 690x103células/mL. Dentre os quartos contralaterais, a CCS foi maior para os quartos com IIM causada por Corynebacterium spp. (194x103células/mL) que em quartos não infectados (81x103células/mL). Não houve efeito de Corynebacterium spp. sobre a produção de leite, gordura, proteína, caseína, lactose, sólidos totais e extrato seco desengordurado. Um total de 222 isolados foram identificados pela MALDI/TOF-MS como Corynebacterium spp., dos quais, Corynebacetium bovis foi o mais frequentemente isolado (n = 208). Espécies não-lipofíficas representaram 4,5% do total de isolados (n=10), destes C. auriscanis (n=3), C. xerosis (n=3), C. amycolatum (n=1), C. casei (n=1), C. efficiens (n=1), C. pseudotuberculosis (n=1). Apenas quatro amostras (1,8%) não foram identificadas ao nível de espécie, Corynebacterium spp. Houve equivalência de resultados de 95% entre as duas técnicas de identificação utilizadas. Em conclusão, IIMs causadas por Corynebacterium spp. não apresentam efeito sobre a produção e composição de leite, porém apresentam aumento significativo da CCS. Adicionalmente, a técnica de MALDI/TOF-MS com o uso da extração em tubo por ácido fórmico/acetonitrila foi aplicada com 91,57% de sensibilidade de identificação das espécies de Corynebacterium nos casos de mastite bovina subclínica, quando comparado aos resultados do sequenciamento de genes 16S rRNA.Mastitis is an inflammation of the mammary glands which bacteria are the most common cause of infections. It is considered a disease with higher prevalence and losses in dairy cows. The subclinical form of mastitis is the most prevalent type of intramammary infection (IMI), and Corynebacterium spp., one of the agents most frequently isolated. Therefore, the main objectives of this study were: 1) to evaluate the effect of subclinical IMI caused by Corynebacterium spp. on milk composition and yield of mammary quarters; 2) to determine the effect of IMI caused by Corynebacterium spp. on the concentration of fat, protein, lactose, casein, total solids, non fat dry milk and somatic cell count (SCC); 3) to evaluate the technique of Matrix-Assisted Laser Desorption Ionization - Time-of-Flight - Mass Spectrometry (MALDI/TOF-MS) for species identification of Corynebacterium isolated from mammary glands. Twenty-one dairy herds were used (n = 1242 animals) on which lactating cows were selected previously identified with IMI caused by Corynebacterium spp. (n = 285). Samples of milk from mammary glands of cows previously identified with IMI caused by Corynebacterium spp. (n = 1140) were collected, identified by microbiological culture and cryopreserved. The strains of Corynebacterium spp. (n = 351) were thawed and recultivated wich were submitted for identification by the technique of sequencing 16S rRNA (gold standard) and MALDI/TOF-MS. For analysis of MALDI/TOF-MS, the isolates were subjected to tube-extraction protocol based on the use of formic acid and acetonitrile. Of the total number of mammary quarters infected by Corynebacterium spp. (n = 190) identified by sequencing 16S rRNA genes, 46 showed contralateral healthy mammary quarters (control). For the collection of milk composition samples and SCC, cows were submitted to a complete milking in individual mammary quarters. The effect of IMI caused by Corynebacterium spp. on milk yield and composition were analyzed using strip-plot design. All mammary quarters infected with Corynebacterium spp. (n = 190) had mean of CCS 690x103cells/mL. Among the contralateral quarters, CCS was higher in quarters with IMI caused by Corynebacterium spp. (194x103células/mL) comparing with uninfected quarters (81x103cells/mL). There was no effect of Corynebacterium spp. on milk yield, on the concentration of fat, protein, casein, lactose, total solids and solids not fat. A total of 222 isolates were identified by MALDI/TOFMS as Corynebacterium spp. of which, Corynebacetium bovis were the most isolated (n = 208). Species no-lipophilic represented 4.5% of isolates (n = 10) of these C. auriscanis (n = 3), C. xerosis (n = 3), C. amycolatum (n = 1), C. casei (n = 1), C. efficiens (n = 1), C. pseudotuberculosis (n = 1). Only four samples (1.8%) were not identified to the specie level. There were equivalence results of 95% between the two identification techniques used. In conclusion, IMI caused by Corynebacterium spp. have no effect on milk yield and composition, but exhibit a significant increase in CCS. Additionally, the technique of MALDI/TOF-MS using the tube-extraction by formic acid/acetonitrile was applied with 91.57% sensitivity for identifying the species of Corynebacterium on cases of bovine mastitis subclinical when compared to the results of genes sequencing 16S rRNA.
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Deblais, Loic. "Understanding of Salmonella-phytopathogen-environment-plant interactions and development of novel antimicrobial to reduce the Salmonella burden in fresh tomato production." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1534437638478448.
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Pereira, Ana Amélia de Souza. "Análise de objetivos e meta-heurísticas para problemas multiobjetivo de sequenciamento da produção." Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/3639.
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O sequenciamento da produção é um processo importante de tomada de decisão usado nas indústrias a fim de alocar tarefas aos recursos. Dada a relevância desse tipo de problema, a pesquisa em programação da produção faz-se necessária. Este trabalho envolve o processo de otimização nos seguintes problemas: máquina única, máquinas paralelas idênticas, máquinas paralelas idênticas com release time, máquinas paralelas não relacionadas com setup time dependente da sequência e das máquinas, e flow shop flexível com setup time dependente da sequência e dos estágios. Além disso, múltiplos e conflitantes objetivos devem ser otimizados ao mesmo tempo na programação de produção, e a literatura vem mostrando avanço nesse sentido. O presente trabalho analisa os objetivos comumente adotados e propõe um conjunto de pares de objetivos. Análise de correlação e árvore de agregação são utilizadas aqui para indicar as possibilidades de agregação entre os objetivos conflitantes. Meta-heurísticas são comumente adotadas para resolver os problemas de escalonamento abordados neste trabalho e duas delas, o Non-dominated Sorting Genetic Algorithm II (NSGA-II) e a Presa Predador (PP), são aplicados aos problemas multiobjetivo propostos a fim de estudar suas adequações aos novos casos. O NSGA-II é um dos Algoritmos Genéticos mais utilizados em problemas de escalonamento. A PP é uma abordagem evolutiva recente para problemas de programação da produção, cada predador é responsável por tratar um único objetivo. Uma generalização para a técnica PP em que os predadores consideram de forma ponderada ambos os objetivos é também proposta. Adicionalmente, a influência da adoção de busca local sobre essas técnicas é analisada. Experimentos computacionais adotando hipervolume como métrica de desempenho foram conduzidos visando avaliar as técnicas computacionais consideradas neste trabalho e suas variantes.
The sequencing of the production is an important process in decision-making and it is used in industries in order to allocate tasks to resources. Given the relevance of this kind of problem, the research in production scheduling is necessary. This study involves the process of optimization in the following problems: single machines, parallel identical machines, parallel identical machines with release time, unrelated parallel machines with setup time dependent on the sequence and on the machines, and flow shop which is flexible with setup time dependent on the sequence and stages. Moreover, multiple and conflicting objectives must be optimized at the same time in production scheduling and the literature has been showing progress in this sense. The present study analyses the commonly adopted objectives and suggests a set of objective pairs. Correlation analysis and aggregation trees are used here to indicate possibilities of aggregation among the conflicting objectives. Metaheuristics are commonly used to solve the sequencing problems addressed in this study and two of them, the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and Predator-Prey(PP), are applied to the proposed multiobjective problems in order to study their adjustments to the new cases. The NSGA-II is one of the most used genetic algorithms in sequencing problems. The PP is a recent evolutionary approach to scheduling problems, where each Predator is responsible for dealing with just one objective. A generalization of the PP technique, in which Predators considered both objectives using weights, is also proposed. In addition, the influence of the adoption of local search on these techniques is analyzed. Computational experiments adopting the hypervolume as a performance measure were conducted aiming at evaluating the computational techniques considered in this study and their variants.
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Silva, Allan Rodrigues da. "Um método de análise de cenários para sequenciamento da produção usando lógica nebulosa." Universidade Federal de São Carlos, 2005. https://repositorio.ufscar.br/handle/ufscar/620.
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Previous issue date: 2005-05-31Universidade Federal de Sao Carlos
Production planning in automated manufacturing environments is a complex task which comprehends, among other activities, the production sequencing. One of the techniques used to determine the best production sequencing is the simulation. All possible sequences can be simulated and, right after that, the sequences with the best performance are verified, according to some criteria. However, due to the combinatory nature of the sequencing, the simulation of all possible combinations takes long time, becoming quite impracticable in many cases. Besides, events that were not programmed occur frequently in automated manufacturing environments and the decision maker must be fast choosing alternatives. Aiming to contour this problem, this work proposes a fuzzy analyser of sceneries for the production sequencing (ANCSP). The goal is to reduce the quantity of sequences to be simulated by the decision maker when non programmed events occur in the productive system, according to a defined performance criteria. The maximum quantity of generated sequences is calculated based on the time avaliable to realize the simulation. The proposed model intends to support the usage of the simulation technique by the decision makers. The ANCSP was implemented and various tests were performed. A specific model of flexible manufacturing system was considered to perform the tests. The performance of the ANCSP was analyzed comparing its results with those presented by a simulation software, for the same test sets and in accordance to the performance measures established.
O planejamento da produção em ambientes automatizados de manufatura é uma tarefa complexa que compreende, dentre outras atividades, o sequenciamento da produção. Uma das técnicas usadas para determinar qual a melhor sequência de produção é a simulação. Todas as sequências possíveis são simuladas e, logo após, verifica-se qual a sequência que obteve o melhor desempenho, de acordo com algum critério. Entretanto, devido à natureza combinatória do sequenciamento, a simulação de todas as sequências possíveis consome muito tempo, tornando-se inviável em muitos casos. Além disso, eventos não programados ocorrem com frequência nos ambientes automatizados de manufatura e o tomador de decisão precisa ter escolhas rápidas. Visando contornar esses problemas, esse trabalho propõe um analisador nebuloso de cen´arios para o sequenciamento da produção (ANCSP). O objetivo é reduzir a quantidade de sequências a serem simuladas pelo tomador de decis ao no momento da ocorrência de eventos não programados no sistema produtivo, de acordo com alguma medida de desempenho. A quantidade máxima de sequências geradas é calculada com base no tempo que o tomador de decisão possui para realizar a simulação. Dessa maneira, o modelo proposto pretende apoiar o uso da técnica de simulação pelos tomadores de decisão. O ANCSP foi implementado e diversos testes foram realizados. Para a realização dos testes, considerou-se um modelo específico de sistema flexível de manufatura. O desempenho do ANCSP foi analisado mediante comparação dos seus resultados com aqueles apresentados por um software de simulação, para o mesmo conjunto de testes e de acordo com as medidas de desempenho estabelecidas.
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Yang, Shu-Jung Sunny The University of New South Wales Australian Graduate School of Management UNSW. "Investment strategies for capacity expansion." Awarded by:The University of New South Wales. Australian Graduate School of Management, 2007. http://handle.unsw.edu.au/1959.4/30158.
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This thesis addresses a problem at the nexus of operations, strategy, and economics: in concentrated markets, on the one hand firms may need to expand capacity in order to improve their competitive position, and on the other they also seek to avoid industry excess capacity causing poor industry conditions to destroy the intended value creation. These considerations are opposite to each other. Too much capacity leads to underutilized resources and drives costs up. In contrast, too little capacity will limit the operation's capability to serve customers and earn revenues. The literature of the operations management and operations research fields on capacity expansion is concerned with normative perspectives to invoke optimization techniques. In this stream of research, competitive capacity expansion is not extensive. Operations related studies often ignore the effect of oligopolistic competition on investment activities but explicitly model practical operational environments. Conversely, the literature of the industrial organization and business strategy fields on strategic investment focuses on quantity/pricing competition in oligopoly markets, and is concerned with descriptive perspectives to invoke game-theoretic modeling, emphasizing the effect of imperfect competition. There is an extensive literature of economics on a subject of capacity investment in oligopolistic competition environments. However, economics-related studies do not often address the detailed operational environments. The thesis focuses on the following five complicated factors affecting the union of operations, strategy, and economics: existing capacity, economies of scale, realistic production strategy, strategic interaction, and demand uncertainty. We make two main contributions. First, we extend the current game-theoretic models of strategic capacity investment by explicitly considering existing capacity, scale economies, and realistic production rules, which are often considered in the operations literature. Under reasonable conditions, we are able to solve the proposed models in closed form. Our second contribution is to use the type of generic strategy as firms' decision variable rather than quantity, price, or timing, which is often used in oligopoly theory. After analyzing equilibrium behaviors in the proposed models, our findings are supported by many empirical observations.
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Módolo, Junior Valdemar. "Estudo comparativo de diferentes representações cromossômicas nos algoritmos genéticos em problemas de sequenciamento da produção em job shop." Universidade Nove de Julho, 2015. http://bibliotecadigital.uninove.br/handle/tede/1371.
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Among the optimization methods, the Genetic Algorithm (GA) has been producing good results in problems with high order of complexity, such as, for example, the production scheduling problem in job shop environment. The production sequencing problems must be translated into a mathematical representation, so that the AG can act. In this process we came up a problematic, the choice between different ways to represent the solution as some representations have limitations, how to present not feasible and / or redundant solutions. Therefore the aim of this study is to conduct a comparative study between different representations of the solution in the AG in production sequencing problems in job shop environments. Two representations of the solution were analyzed, the priority lists based and based on order of operations and compared with a binary representation, in the context of sequencing problem set defined by Lawrence (1984). The results were evaluated according to the total processing time (makespan), the computational cost and the proportion of generated feasible solutions. It was noticed that the representation of the solution based on order of operations, which produced 100% of feasible solutions, was the one that showed the best results although no convergence to the best known solution to every problem.
Dentre os métodos de otimização, o Algoritmo Genético (AG) vem produzindo bons resultados em problemas com ordem de complexidade elevada, como é o caso, por exemplo, do problema de sequenciamento da produção em ambiente job shop. Os problemas de sequenciamento da produção devem ser traduzidos para uma representação matemática, para que o AG possa atuar. Neste processo surgi uma problemática, a escolha entre as diferentes formas de se representar a solução visto que algumas representações apresentam limitações, como apresentar soluções não factíveis e/ou redundantes. Portanto o objetivo deste trabalho é realizar um estudo comparativo entre diferentes representações da solução no AG em problemas de sequenciamento da produção em ambientes job shop. Duas representações da solução foram analisadas, a baseada em listas de prioridades e a baseada em ordem de operações e comparada com uma representação binária, no contexto do conjunto de problemas de sequenciamento definidos por Lawrence (1984). Os resultados foram avaliados em função do tempo total de processamento (makespan), do custo computacional e da proporção de soluções factíveis geradas. Percebeu-se que, a representação da solução baseada em ordem de operações, a qual produziu 100% de soluções factíveis, foi a que mostrou os melhores resultados apesar de não apresentar convergência para a melhor solução conhecida em todos os problemas.
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Kucukkoc, Ibrahim. "Modelling and solving mixed-model parallel two-sided assembly line problems." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/18917.
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The global competitive environment and the growing demand for personalised products have increased the interest of companies in producing similar product models on the same assembly line. Companies are forced to make significant structural changes to rapidly respond to diversified demands and convert their existing single-model lines into mixed-model lines in order to avoid unnecessary new line construction cost for each new product model. Mixed-model assembly lines play a key role in increasing productivity without compromising quality for manufacturing enterprises. The literature is extensive on assembling small-sized products in an intermixed sequence and assembling large-sized products in large volumes on single-model lines. However, a mixed-model parallel two-sided line system, where two or more similar products or similar models of a large-sized product are assembled on each of the parallel two-sided lines in an intermixed sequence, has not been of interest to academia so far. Moreover, taking model sequencing problem into consideration on a mixed-model parallel two-sided line system is a novel research topic in this domain. Within this context, the problem of simultaneous balancing and sequencing of mixed-model parallel two-sided lines is defined and described using illustrative examples for the first time in the literature. The mathematical model of the problem is also developed to exhibit the main characteristics of the problem and to explore the logic underlying the algorithms developed. The benefits of utilising multi-line stations between two adjacent lines are discussed and numerical examples are provided. An agent-based ant colony optimisation algorithm (called ABACO) is developed to obtain a generic solution that conforms to any model sequence and it is enhanced step-by-step to increase the quality of the solutions obtained. Then, the algorithm is modified with the integration of a model sequencing procedure (where the modified version is called ABACO/S) to balance lines by tracking the product model changes on each workstation in a complex production environment where each of the parallel lines may a have different cycle time. Finally, a genetic algorithm based model sequencing mechanism is integrated to the algorithm to increase the robustness of the obtained solutions. Computational tests are performed using test cases to observe the performances of the developed algorithms. Statistical tests are conducted through obtained results and test results establish that balancing mixed-model parallel two-sided lines together has a significant effect on the sought performance measures (a weighted summation of line length and the number of workstations) in comparison with balancing those lines separately. Another important finding of the research is that considering model sequencing problem along with the line balancing problem helps algorithm find better line balances with better performance measures. The results also indicate that the developed ABACO and ABACO/S algorithms outperform other test heuristics commonly used in the literature in solving various line balancing problems; and integrating a genetic algorithm based model sequencing mechanism into ABACO/S helps the algorithm find better solutions with less amount of computational effort.
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Silva, Rafael Rabêlo. "Um framework para construção de sistemas inteligentes de seqüenciamento da produção." Universidade Federal de São Carlos, 2009. https://repositorio.ufscar.br/handle/ufscar/464.
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Previous issue date: 2009-11-27There are many researches being developed in the Production Sequencing and Production Scheduling by the Tear team. In one of the researches focus, it has been investigated the use of simulation in cooperation with Artificial Intelligence to obtain a computer system as the solution of a reactive system in the entrance of production system. The main goal is to have a framework model to an intelligent system to help the products sequencing in the entrance of production systems. The framework should be a guide in the construction and customization of the intelligent system to be constructed.
No Tear (Laboratório de Pesquisa e Desenvolvimento de Tecnologia e Estratégias de Automação) vários trabalhos vêm sendo desenvolvidos na temática de seqüenciamento e programação da produção. Em um dos focos, o de seqüenciamento de produtos na entrada de um sistema produtivo, tem-se investigado o uso de simulação em cooperação com técnicas de Inteligência Artificial buscando-se uma aplicação como solução para condições de re-seqüenciamento ou de seqüenciamento reativo da entrada do sistema produtivo. A proposta deste trabalho é modelar um framework para um sistema de auxílio ao seqüenciamento na entrada do sistema produtivo. O framework deve servir como guia na construção e customização do sistema.
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Yepes, Borrero Juan Camilo. "Secuenciación de máquinas con necesidad de ajustes y recursos adicionales." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/158742.
Full textAbstract:
[ES] En esta tesis doctoral se estudia el problema de secuenciación de máquinas paralelas no relacionadas con necesidad de ajustes y recursos adicionales asignados en los ajustes. En este problema, se tiene un grupo de tareas (también llamadas trabajos), donde cada una debe ser procesada en una de las máquinas paralelas disponibles. Para procesar una tarea después de otra en la misma máquina, se debe hacer un ajuste en la máquina. Se asume que estos ajustes deben ser realizados por un recurso adicional limitado (por ejemplo, operarios). En esta tesis doctoral se estudian dos variantes del problema planteado: 1) considerando el problema con el único objetivo de minimizar el tiempo máximo de finalización de todos los trabajos (makespan), y 2) considerando el problema multi-objetivo minimizando simultáneamente el makespan y el consumo máximo de recursos adicionales.
Inicialmente, se realiza una completa revisión bibliográfica sobre estudios relacionados con el problema planteado. En esta revisión se detecta que, a pesar de existir numerosos estudios de secuenciación de máquinas paralelas, no muchos de estos estudios tienen en cuenta recursos adicionales. Posteriormente, para introducir el problema a estudiar antes de plantear métodos de resolución, se realiza una breve explicación de los principales problemas de secuenciación de máquinas paralelas.
El problema de un solo objetivo está clasificado como NP-Hard. Por ello, para abordar su resolución se han diseñado e implementado heurísticas y metaheurísticas siguiendo dos enfoques diferentes. Para el primer enfoque, que ignora la información sobre el consumo de recursos adicionales en la fase constructiva, se adaptan dos de los mejores algoritmos existentes en la literatura para el problema de máquinas paralelas con ajustes sin necesidad de recursos adicionales. En el segundo enfoque, que sí tiene en cuenta la información sobre el consumo de recursos adicionales en la fase constructiva, se proponen nuevos algoritmos heurísticos y metaheurísticos para resolver el problema. Tras analizar los resultados de los experimentos computacionales realizados, concluimos que hay diferencias entre los dos enfoques, siendo significativamente mejor el enfoque que tiene en cuenta la información sobre los recursos adicionales.
Al igual que en el caso de un solo objetivo, la complejidad del problema multi-objetivo obliga a presentar algoritmos heurísticos o metaheurísticos para resolverlo. En esta tesis se presenta un nuevo algoritmo metaheurístico multi-objetivo eficiente para encontrar buenas aproximaciones a la frontera de Pareto del problema. Además, se adaptaron otros tres algoritmos que han mostrado buenos resultados en diferentes estudios de problemas de secuenciación de máquinas multi-objetivo. Después de realizar experimentos computacionales exhaustivos, concluimos que el nuevo algoritmo propuesto en esta tesis es significativamente mejor que los otros tres algoritmos existentes, y que se han adaptado para resolver este problema.[CAT] En aquesta tesi doctoral s'estudia el problema de seqüenciació de màquines paral·leles no relacionades amb necessitat d'ajustos i recursos addicionals assignats en els ajustos. En aquest problema, es tenen un grup de tasques (també anomenades treballs), on cadascuna ha de ser processada en una de les màquines paral·leles disponibles. Per processar una tasca després d'una altra en la mateixa màquina, s'ha de fer un ajustament en la màquina. S'assumeix que aquests ajustos en les màquines per a processar una tasca després del processament d'una altra, han de ser realitzats per un recurs addicional limitat (per exemple, operaris). En aquesta tesi doctoral s'estudien dos variants al problema plantejat: 1) considerant el problema com l'únic objectiu de minimitzar el temps màxim de finalització de tots els treballs (makespan), i 2) considerant el problema multi-objectiu minimitzant simultàniament el makespan i el consum màxim de recursos addicionals. Inicialment, es realitza una completa revisió bibliogràfica sobre estudis relacionats amb el problema plantejat. En esta revisió es detecta que, tot i existir nombrosos estudis de seqüenciació de màquines paral·leles, hi ha molts pocs que tenen en compte recursos addicionals. Posteriorment, per introduir el problema a estudiar abans de plantejar mètodes de resolució, es realitza una breu explicació dels principals problemes de seqüenciació de màquines paral·leles. El problema d'un sol objectiu està classificat com NP-Hard. Per això, per abordar la seua resolució s'han dissenyat i implementat heurístiques y metaheurístiques seguint dos enfocs diferents. El primer enfoc ignora la informació sobre el consum de recursos en la fase constructiva, adaptant dos dels millors algoritmes existents en la literatura per al problema de seqüenciació de màquines paral·leles amb ajustaments sense necessitat de recursos. Per al segon enfoc si es té en compte la informació sobre el consum de recursos en la fase constructiva. Després d'analitzar els resultats dels experiments computacionals realitzats, concloem que hi ha diferencies entre els dos enfocs, sent significativament millor l'enfoc que té en compte la informació sobre el recursos. De la mateixa manera que en el cas d'un sol objectiu, la complexitat del problema multi-objectiu obliga a presentar algoritmes heurístics o metaheurístics per a resoldre-ho. En aquesta tesi es presenta un nou algoritme metaheurístic multi-objectiu eficient per trobar bones aproximacions a la frontera de Pareto del problema. A més, es van adaptar altres tres algoritmes que han mostrat bons resultats en diferents estudis de problemes de seqüenciació de màquines multi-objectiu. Després de realitzar experiments computacionals exhaustius, concloem que el nou algoritme proposat en aquesta tesi és significativament millor que els altres tres algoritmes existents i que s'han adaptat per resoldre aquest problema.
[EN] In this thesis we study the unrelated parallel machine scheduling problem with setup times and additional limited resources in the setups. In this problem, we have a group of tasks (also called jobs), where each one must be processed on one of the available parallel machines. To process one job after another on the same machine, a setup must be made on the machine. It is assumed that these setups on machines must be made by a limited additional resource (eg, operators). In this thesis two variants of the problem are studied: 1) considering the problem with the objective of minimizing the maximum completion time of all jobs (makespan), and 2) considering the multi-objective problem, minimizing the makespan and the maximum consumption of additional resources. Initially, a complete literature review is carried out on studies related to the problem addressed in this thesis. This review finds that despite numerous parallel machine scheduling studies, there are very few that take into account additional resources. Subsequently, to introduce the problem addressed before proposing resolution methods, a brief explanation of the main parallel machines scheduling problems is made. The problem with a single objective is classified as NP-Hard. Therefore, to solve it, heuristics and metaheuristics have been designed and implemented following two different approaches. For the first approach, which ignores the information on the consumption of resources in the construction phase, two of the best algorithms existing in the literature for the problem of parallel machines with setups without additional resources are adapted. For the second approach, which does take into account information on the consumption of resources in the construction phase, new heuristic and metaheuristic algorithms are proposed to solve the problem. Following the results of the computational experiments, we conclude that there are differences between the two approaches, the approach that takes into account the information on resources being significantly better. As in the case of a single objective, the complexity of the multi-objective problem requires the formulation of heuristic or metaheuristic algorithms to solve it. In this thesis, a new efficient multi-objective metaheuristic algorithm is presented to find good approximations to the Pareto front of the problem. In addition, three other algorithms that have shown good results in different studies of multi-objective machine scheduling problems were adapted. After carrying out exhaustive computational experiments, we concluded that the new algorithm proposed in this thesis is significantly better than the other three adapted algorithms.
Yepes Borrero, JC. (2020). Secuenciación de máquinas con necesidad de ajustes y recursos adicionales [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158742
TESIS
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Maruyama, Kazunori Ph D. Mie University. "Genome sequencing technology : improvement of the electrophoretic sequencing process and analysis of the sequencing tool industry." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34868.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2005.Includes bibliographical references.
A primary bottleneck in DNA-sequencing operations is the capacity of the detection process. Although today's capillary electrophoresis DNA sequencers are faster, more sensitive, and more reliable than their precursors, high purchasing and running costs still make them a limiting factor in most laboratories like those of the Broad Institute. It is important to run those sequencers as efficiently as possible to reduce costs while producing robust assemblies. Polymer media for electrophoresis is the most important determinant for sequencing throughput. This thesis investigates the effect of polymer media on the performance of Applied Biosystems (ABI) 3730xl, the de-facto standard of DNA sequencers and develops analysis procedures for ABI3730xl system and its data. Due to its use in the human genome project (HGP), ABI has established a monopolistic position in the DNA-sequencing tool industry. As the de-facto standard of DNA sequencers ABI3730xl is highly automated, well-optimized, and black-boxed, despite the importance of higher throughput sequencing for diagnostic applications, third parties have found it difficult to improve sequencing methods.
(cont.) This thesis also conducts an analysis of the DNA-sequencing tool industry to discuss how ABI has established current monopolistic status, what kind of business model would be attractive for ABI in the post-HGP period, how new companies can successfully enter this industry, and how they can keep improving DNA-sequencing throughput along the line of "Moore's law".
by Kazunori Maruyama.
S.M.
M.B.A.
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Klevebring, Daniel. "On Transcriptome Sequencing." Doctoral thesis, KTH, Genteknologi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11446.
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This thesis is about the use of massive DNA sequencing to investigate the transcriptome. During recent decades, several studies have made it clear that the transcriptome comprises a more complex set of biochemical machinery than was previously believed. The majority of the genome can be expressed as transcripts; and overlapping and antisense transcription is widespread. New technologies for the interroga- tion of nucleic acids have made it possible to investigate such cellular phenomena in much greater detail than ever before. For each application, special requirements need to be met. The work presented in this thesis focuses on the transcrip- tome and the development of technology for its analysis. In paper I, we report our development of an automated approach for sample preparation. The procedure was benchmarked against a publicly available reference data set, and we note that our approach outperformed similar manual procedures in terms of reproducibility. In the work reported in papers II-IV, we used different massive sequencing technologies to investigate the transcriptome. In paper II we describe a concatemerization approach that increased throughput by 65% using 454 sequencing,and we identify classes of transcripts not previously described in Populus. Papers III and IV both report studies based on SOLiD sequencing. In the former, we investigated transcripts and proteins for 13% of the human gene and detected a massive overlap for the upper 50% transcriptional levels. In the work described in paper IV, we investigated transcription in non-genic regions of the genome and detected expression from a high number of previ- ously unknown loci.QC 20100723
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Allan, John S. Nekimken Kyle J. Weills Spencer B. "Pump sequencing optimization /." Click here to view, 2009. http://digitalcommons.calpoly.edu/mesp/7.
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Thesis (B.S.)--California Polytechnic State University, 2009.Project advisor: Tom Mase. Title from PDF title page; viewed on Jan. 13, 2010. Includes bibliographical references. Also available on microfiche.
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Shriver, Zachary (Zachary Holmes) 1973. "Sequencing complex polysaccharides." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/17515.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Division of Bioengineering and Environmental Health, 2001.Includes bibliographical references (leaves 136-140).
Glycosaminoglycans are complex polysaccharides that exist at the cell/extracellular matrix interface. As such, these information-dense molecules are key regulators of extracellular signals. However, to date, there has been a lack of effective biochemical and analytical tools for the analysis of glycosaminoglycan structure and hence, there is very little understanding of exactly how glycosaminoglycan structure impinges on function. Development of such tools is especially important for a key subset of glycosaminoglycans, i.e., heparin/heparan sulfate-like glycosaminoglycans (HLGAGs). As a first step in the development of tools to study HLGAG structure, biochemical studies were completed on the heparinases, a family of three HLGAG-degrading enzymes from Flavobacterium heparinum. With heparinase I, it was found that calcium is a necessary cofactor for optimal activity and that two putative calcium coordinating motifs exist in heparinase I. With heparinase II, a single cysteine and three histidines were found to be critical for proper enzymatic function. Finally, with heparinase III, two histidines were found to be catalytically important.
(cont.) In addition to the development of the heparinases, sensitive analytical methodologies were developed to determine HLGAG structure. A novel mass spectrometric procedure was developed and used to define heparinase's II mechanism of action on defined oligosaccharide substrates. In addition, capillary electrophoresis, in combination with heparinase digestion, was used for the compositional analysis of HLGAG oligosaccharides. Coupling of these analytical techniques with a property-encoded nomenclature to handle the information density of HLGAGs enabled the development of a sequencing procedure for HLGAGs. These procedures were then used to probe a number of key biological processes that are mediated by HLGAGs. The sequencing approach developed herein was used to determine the structure of HLGAG oligosaccharides involved in hemostasis and viral binding. In addition, these approaches were used to probe HLGAG binding by clinically and biologically important signaling molecules, viz., fibroblast growth factor and endostatin. Together, these studies represent a foundation with which it possible to develop further HLGAG structure/function relationships, opening new avenues of research and making possible HLGAG-based therapeutics.
by Zachary Shriver.
Ph.D.
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Vacher, Blandine. "Techniques d'optimisation appliquées au pilotage de la solution GTP X-PTS pour la préparation de commandes intégrant un ASRS." Thesis, Compiègne, 2020. http://www.theses.fr/2020COMP2566.
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Les travaux présentés dans ce document portent sur des problèmes d'optimisation dans le domaine de la logistique interne des entrepôts. Le domaine est soumis à une forte concurrence et est en plein essor, poussé par les besoins croissants du marché et favorisé par l'automatisation. L'entreprise SAVOYE construit des équipements et propose sa propre solution GTP (Goods-To-Person) pour la préparation de commandes. La solution utilise un système de stockage automatisé appelé X-Picking Tray System (X-PTS) et achemine les charges automatiquement à des postes de travail via des carrousels pour effectuer des opérations séquencées. C'est un système de systèmes particulièrement complexe qui offre de nombreuses applications aux techniques de la recherche opérationnelle. Tout cela définit le périmètre applicatif et théorique des travaux menés dans cette thèse. Nous avons d'abord traité un problème d'ordonnancement de type Job Shop avec des contraintes de précédences. Le contexte particulier du problème a permis de le résoudre en un temps polynomial avec un algorithme exact. Celui-ci a permis de calculer les dates d'injection des charges provenant des différents flux de sortie du stockage pour s'agréger sur un carrousel, dans un ordre donné. Ainsi, la gestion inter-allées du stockage PTS a été améliorée et le débit du flux de charges maximisé, depuis le stockage jusqu'à un poste. Nous avons ensuite étudié des algorithmes de tri tels que le tri par base et développé un algorithme de tri en ligne, utilisé pour piloter des systèmes autonomes de tri appelés Buffers Séquenceurs (BS). Placés en amont de chaque poste de travail dans la solution GTP, les BS permettent de délocaliser la fonction de tri en aval du stockage, augmentant de facto le débit des flux de sortie. Enfin, nous avons considéré un problème de séquencement consistant à trouver une extension linéaire d'un ordre partiel minimisant une distance avec un ordre donné. Nous proposons de le résoudre par une approche de programmation linéaire en nombres entiers, par la construction de programmes dynamiques et par des heuristiques de type glouton. Une heuristique efficace a été développée en se basant sur des appels itératifs d'un des programmes dynamiques, permettant d'atteindre une solution proche ou égale à l'optimum en un temps très court. L'application de ce problème aux flux de sortie non ordonnés du stockage X-PTS permet de réaliser un pré-tri au niveau des carrousels. Les diverses solutions développées ont été validées par simulation et certaines ont été brevetées et/ou déjà été mises en application dans des entrepôtsThe work presented in this PhD thesis deals with optimization problems in the context of internal warehouse logistics. The field is subject to strong competition and extensive growth, driven by the growing needs of the market and favored by automation. SAVOYE builds warehouse storage handling equipment and offers its own GTP (Goods-To-Person) solution for order picking. The solution uses an Automated Storage and Retrieval System (ASRS) called X-Picking Tray System (X-PTS) and automatically routes loads to workstations via carousels to perform sequenced operations. It is a highly complex system of systems with many applications for operational research techniques. All this defines the applicative and theoretical scope of the work carried out in this thesis. In this thesis, we have first dealt with a specific scheduling Job Shop problem with precedence constraints. The particular context of this problem allowed us to solve it in polynomial time with exact algorithms. These algorithms made it possible to calculate the injection schedule of the loads coming from the different storage output streams to aggregate on a carousel in a given order. Thus, the inter-aisle management of the X-PTS storage was improved and the throughput of the load flow was maximized, from the storage to a station. In the sequel of this work, the radix sort LSD (Least Significant Digit) algorithm was studied and a dedicated online sorting algorithm was developed. The second one is used to drive autonomous sorting systems called Buffers Sequencers (BS), which are placed upstream of each workstation in the GTP solution. Finally, a sequencing problem was considered, consisting of finding a linear extension of a partial order minimizing a distance with a given order. An integer linear programming approach, different variants of dynamic programming and greedy algorithms were proposed to solve it. An efficient heuristic was developed based on iterative calls of dynamic programming routines, allowing to reach a solution close or equal to the optimum in a very short time. The application of this problem to the unordered output streams of X-PTS storage allows pre-sorting at the carousel level. The various solutions developed have been validated by simulation and some have been patented and/or already implemented in warehouses
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Conceição, Vinicius Masquetti da. "Reator anaeróbio serial (RAS) aplicado no processamento de vinhaça de cana-de-açúcar." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-04042017-113113/.
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O objetivo deste trabalho foi estudar a aplicação de reator anaeróbio serial (RAS) no processamento de vinhaça de cana-de-açúcar para a remoção de matéria orgânica e produção de biogás, submetido ao aumento gradativo de carregamento orgânico. Para tanto, foi utilizado um reator composto por quatro câmaras em série denominadas C1, C2, C3 e C4, com capacidade de 5 L cada, totalizando um volume de 20 L. A primeira etapa do trabalho (Etapa 1) consistiu na operação e monitoramento do reator RAS partindo-se da aplicação da carga orgânica volumétrica (COV) de 0,5 kg DQO m-3.d-1 até a obtenção da COV de 2,5 kg DQO m-3.d-1. Na segunda etapa (Etapa 2) foram operados reatores em batelada sequencial, simulando a operação contínua do reator RAS, visando estudar o efeito do aumento de taxas de carregamento orgânico aplicado. O reator RAS operou sob baixos valores de COVglobal e COALglobal aplicados na Etapa 1, obtendo-se máximas de 2,50 kg DQO m-3.d-1 e 0,167 kg STV m-3.d-1, respectivamente. Os resultados obtidos da Etapa 1 indicam satisfatória remoção global média de matéria orgânica na forma de DQO, superiores a 90 %, propiciada pela adaptação da biomassa ao longo dos reatores sequenciais. O metano apresentou-se como o gás predominante na composição do biogás produzido, com valores acima de 75 %, que confirmam o estabelecimento do sistema metanogênico pleno. Em todos os compartimentos dos reatores sequenciais verificou-se maior abundância relativa para os domínios Archaea e Bacteria os gêneros Methanosaeta, produtores de metano e, T78, responsável pela degradação de açúcares, respectivamente. Principalmente para os reatores C3 e C4, observou-se adaptação de algumas populações para ambos os domínios Bacteria e Archaea indicado pelo menor índice de diversidade e aumento da dominância. O aumento das taxas de carregamento orgânico aplicado ao lodo, estipuladas nos ensaios em batelada na Etapa 2, propiciou o aumento dos valores de carga orgânica aplicada para todos os reatores. Com o aumento do carregamento orgânico aplicado, observa-se o aumento e acúmulo de ácidos orgânicos para todas as fases dos ensaios, principalmente o acético. A produção de metano foi significativa na operação dos reatores em batelada, principalmente em C1. De forma geral, os resultados obtidos demonstraram o bom desempenho do processamento da vinhaça de cana-de açúcar em reator compartimentado tipo RAS para a remoção de matéria orgânica e produção de biogás.The aim of this study was to investigate the application of an anaerobic serial reactor (ASR) in the sugarcane stillage processing for the removal of organic matter and biogas production, submitted to the gradual increase in organic loading rate. ASR reactor consisted of four reactors operated in series (C1, C2, C3 and C4), each with a reaction volume of 5 L (total volume of 20 L). The first step (Step 1) consisted of reactor operation and monitoring; organic loading rate was gradually increased from 0.5 kg COD m-3d-1 up to 2.5 kg COD m-3 d-1. In the second step (Step 2), sequential batch reactors were operated, simulating the continuous ASR reactor operation, aiming to study the effect of the increase of organic load applied to sludge (OLS). The ASR reactor operated under low values of COVglobal and COALglobal applied in Step 1, obtaining a maximum 2.50 kg COD m-3d-1 and 0.167 kg TVS/m-3d-1, respectively. The results obtained from Step 1 indicated satisfactory removal of the global average organic matter in the form of COD more than 90 %, caused by adaptation of the biomass along the sequential reactors. Methane appeared to be the predominant gas in biogas composition, with values above 75%, which confirmed the establishment of the full methanogenic system. In all compartments of the sequential reactors, there was a higher relative abundance for the domains Archaea and Bacteria of the genera Methanosaeta, methane producers, and T78, which is responsible for degradation of sugars, respectively. Especially for the reactors C3 and C4, the adaptation of some populations for both domains Bacteria and Archaea indicated was observed by the lower diversity index and increase in dominance. The increase of the organic loading rates applied to the sludge, as established in the batch tests, increased the organic load values applied to all reactors. With the increase of organic loading applied, an increase in the accumulation of organic acids, mainly acetic, for all stages and the batch tests. Methane production was significant in the operation of batch reactors, mainly in the C1. In general, the results obtained showed good performance of the processing of the sugarcane stillage in serial reactor (ASR) for the removal of organic matter and biogas production.
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Chen, Ying-Ja. "DNA sequencing by denaturation." Diss., [La Jolla] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p3359122.
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Thesis (Ph. D.)--University of California, San Diego, 2009.Title from first page of PDF file (viewed July 14, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 87-91).
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Roguski, Łukasz 1987. "High-throughput sequencing data compression." Doctoral thesis, Universitat Pompeu Fabra, 2017. http://hdl.handle.net/10803/565775.
Full textAbstract:
Thanks to advances in sequencing technologies, biomedical research has experienced a revolution over recent years, resulting in an explosion in the amount of genomic data being generated worldwide. The typical space requirement for storing sequencing data produced by a medium-scale experiment lies in the range of tens to hundreds of gigabytes, with multiple files in different formats being produced by each experiment. The current de facto standard file formats used to represent genomic data are text-based. For practical reasons, these are stored in compressed form. In most cases, such storage methods rely on general-purpose text compressors, such as gzip. Unfortunately, however, these methods are unable to exploit the information models specific to sequencing data, and as a result they usually provide limited functionality and insufficient savings in storage space. This explains why relatively basic operations such as processing, storage, and transfer of genomic data have become a typical bottleneck of current analysis setups.
Therefore, this thesis focuses on methods to efficiently store and compress the data generated from sequencing experiments. First, we propose a novel general purpose FASTQ files compressor. Compared to gzip, it achieves a significant reduction in the size of the resulting archive, while also offering high data processing speed. Next, we present compression methods that exploit the high sequence redundancy present in sequencing data. These methods achieve the best compression ratio among current state-of-the-art FASTQ compressors, without using any external reference sequence. We also demonstrate different lossy compression approaches to store auxiliary sequencing data, which allow for further reductions in size. Finally, we propose a flexible framework and data format, which allows one to semi-automatically generate compression solutions which are not tied to any specific genomic file format. To facilitate data management needed by complex pipelines, multiple genomic datasets having heterogeneous formats can be stored together in configurable containers, with an option to perform custom queries over the stored data. Moreover, we show that simple solutions based on our framework can achieve results comparable to those of state-of-the-art format-specific compressors.
Overall, the solutions developed and described in this thesis can easily be incorporated into current pipelines for the analysis of genomic data. Taken together, they provide grounds for the development of integrated approaches towards efficient storage and management of such data.Gràcies als avenços en el camp de les tecnologies de seqüenciació, en els darrers anys la recerca biomèdica ha viscut una revolució, que ha tingut com un dels resultats l'explosió del volum de dades genòmiques generades arreu del món. La mida típica de les dades de seqüenciació generades en experiments d'escala mitjana acostuma a situar-se en un rang entre deu i cent gigabytes, que s'emmagatzemen en diversos arxius en diferents formats produïts en cada experiment. Els formats estàndards actuals de facto de representació de dades genòmiques són en format textual. Per raons pràctiques, les dades necessiten ser emmagatzemades en format comprimit. En la majoria dels casos, aquests mètodes de compressió es basen en compressors de text de caràcter general, com ara gzip. Amb tot, no permeten explotar els models d'informació especifícs de dades de seqüenciació. És per això que proporcionen funcionalitats limitades i estalvi insuficient d'espai d'emmagatzematge. Això explica per què operacions relativament bàsiques, com ara el processament, l'emmagatzematge i la transferència de dades genòmiques, s'han convertit en un dels principals obstacles de processos actuals d'anàlisi. Per tot això, aquesta tesi se centra en mètodes d'emmagatzematge i compressió eficients de dades generades en experiments de sequenciació. En primer lloc, proposem un compressor innovador d'arxius FASTQ de propòsit general. A diferència de gzip, aquest compressor permet reduir de manera significativa la mida de l'arxiu resultant del procés de compressió. A més a més, aquesta eina permet processar les dades a una velocitat alta. A continuació, presentem mètodes de compressió que fan ús de l'alta redundància de seqüències present en les dades de seqüenciació. Aquests mètodes obtenen la millor ratio de compressió d'entre els compressors FASTQ del marc teòric actual, sense fer ús de cap referència externa. També mostrem aproximacions de compressió amb pèrdua per emmagatzemar dades de seqüenciació auxiliars, que permeten reduir encara més la mida de les dades. En últim lloc, aportem un sistema flexible de compressió i un format de dades. Aquest sistema fa possible generar de manera semi-automàtica solucions de compressió que no estan lligades a cap mena de format específic d'arxius de dades genòmiques. Per tal de facilitar la gestió complexa de dades, diversos conjunts de dades amb formats heterogenis poden ser emmagatzemats en contenidors configurables amb l'opció de dur a terme consultes personalitzades sobre les dades emmagatzemades. A més a més, exposem que les solucions simples basades en el nostre sistema poden obtenir resultats comparables als compressors de format específic de l'estat de l'art. En resum, les solucions desenvolupades i descrites en aquesta tesi poden ser incorporades amb facilitat en processos d'anàlisi de dades genòmiques. Si prenem aquestes solucions conjuntament, aporten una base sòlida per al desenvolupament d'aproximacions completes encaminades a l'emmagatzematge i gestió eficient de dades genòmiques.