Dissertations / Theses on the topic 'Logistic design'

In order to determine the potency of the test preparation relative to the standard preparation, it is often important to test parallelism between a pair of dose-response curves of reference standard and test sample. Optimal designs are known to be more powerful in testing parallelism as compared to classical designs. In this study, D-optimal design was implemented to study the parallelism and compare its performance with a classical design. We modified Doptimal design to test the parallelism in the four-parameter logistic (4PL) model using Intersection-Union Test (IUT). IUT method is appropriate when the null hypothesis is expressed as a union of sets, and by using this method complicated tests involving several parameters are easily constructed. Since D-optimal design minimizes the variances of model parameters, it can bring more power to the IUT test. A simulation study will be presented to compare the empirical properties of the two different designs.

A concept for the mathematical modeling of multiple repairable equipment and logistic systems (MREAL systems) is developed; These systems consist of multiple populations of repairable equipment, and their associated design, procurement, maintenance, and supply support. MREAL systems present management and design problems which parallel the·management and design of multiple, consumable item inventory systems. However, the MREAL system is more complex since it has a repair component. The MREAL system concept is described in a classification hierarchy which attempts to categorize the components of such systems. A specific mathematical model (MREAL1) is developed for a subset of these components. Included in MREAL1 are representations of the equipment reliability and maintainability design problem, the maintenance capacity problem, the retirement age problem, and the population size problem, for each of the multiple populations. MREAL1 models the steady state stochastic behavior of the equipment repair facilities using an approximation which is based upon the finite source, multiple server queuing system. System performance measures included in MREAL1 are: the expected MREAL total system life cycle cost (including a shortage cost penalty); the steady state expected number of shortages; the probability of catastrophic failure in each equipment population; and two budget based measures of effectiveness. Two optimization methods are described for a test problem developed for MREAL1. The first method computes values of the objective function and the constraints for a specified subset of the solution space. The best feasible solution found is recorded. This method can also examine all possible solutions, or can be used in a manual search. The second optimization method performs an exhaustive enumeration. of the combinatorial programming portion of MREAL1, which represents equipment design. For each enumerated design combination, an attempt is made to find the optimal solution to the remaining nonlinear discrete programming problem. A sequential unconstrained minimization technique is used which is based on an augmented Lagrangian penalty function adapted to the integer nature of MREAL1. The unconstrained minimization is performed by a combination of Rosenbrock's search technique, the steepest descent method, and Fibonacci line searches, adapted to the integer nature of the search. Since the model contains many discrete local minima, the sequential unconstrained minimization is repeated from different starting solutions, based upon a heuristic selection procedure. A gradient projection method provides the termination criteria for each unconstrained minimization.
Ph. D.

In the 21st century, e-commerce (electronic commerce) has witnessed explosive development, while the problems such as the imperfect logistics system and backward information platform exposed are also increasing. This research thesis focuses on the design of electronic commerce project logistics under collaborative theory. Firstly, this research analyses the current situation of e-commerce, and explains relevant theories of system engineering and collaborative theory. Secondly, a management framework of e-commerce under collaborative theory is discussed. Then it is about the construction of a new and novel logistics system, that is, a four-stage radial-spoke logistics network containing e-commerce hubs, e-commerce regional distribution centres, e-commerce physical stores, and e-commerce cooperatives. The existing logistics mode is innovated and developed with the “collaborative distribution” mode proposed, and the entire supply chain is connected through the four-stage radial-spoke logistics network, enabling all parties involved in the supply chain to achieve collaboration. Then based on the network, containers are differentiated and standardized into four classes. What’s more, with the design and development of a collaborative logistics system, this thesis presents countermeasures to integrate e-commerce with its internal management platform. So the growing information is effectively managed, timely and correct decision-making information and decision support are provided. Furthermore, previous e-commerce platform is strengthened and the collaborative theory is fundamentally applied in a novel context. Finally, combining together logistics alliance, e-commerce platforms as well as its management system, this research is aimed to improve e-commerce collaborative management and promote e-commerce collaborative theory.
Thesis (PhD)--University of Pretoria, 2020.
Graduate School of Technology Management (GSTM)
PhD
Unrestricted

Thesis (S.M.)--Massachusetts Institute of Technology, Computation for Design and Optimization Program, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 57-58).
The thesis aims to provide a way to identify better matches between buyers and suppliers who are using an e-procurement platform provided by a US based worldwide online market company. The goal is to enhance the shopping experience of the clients, increase the retention rate and grow the customer base of the company. We establish two logistic regression models. The first model is to predict the probability of suppliers winning an RFQ (request for quote). From the calculated probabilities, we are able to rank all the suppliers and tell the buyers who may be the most qualified providers for them. Also, the suppliers will be aware of their odds of winning among all the competitors. Our model shows that price is the most decisive factor for winning, and geography and prior business relationships with the buyer are also important. The second model is used to estimate the probability of successfully awarding an RFQ. We model how likely the RFQ is to be awarded by the buyer. Such information will be especially helpful to suppliers. The process of the RFQ and the relation and intention of the buyer seem to be the most influential factors.
by Shuo Tian.
S.M.

A new economic model for the evaluation of integrated Design, Production, and Logistic Support Systems (DPLSSs) is designed and developed in this thesis. The DPLSS model was created after a survey of Life Cycle Costing (LCC) applications revealed that no models for assessing integrated design, production, and logistic support systems were available. The evaluation technique the model is based on is called Life Cycle Value Assessment (LCVA). LCVA differs from LCC in that it emphasizes consideration of life cycle revenues as well as costs.

The system addressed by the DPLSS model has a life cycle which includes product design, production capability design and construction, production, product distribution, logistic system support and maintenance, and system disposal. The baseline production capability assumed when developing the DPLSS model involves batch processing, forming the base material into individual units, and performing detailed processing operations. It has also been assumed that items produced are non-repairable.

The DPLSS model facilitates the evaluation of new DPLSSs by leading managers through the new LCVA methodology, A Cost Breakdown Structure (CBS) which is compatible with the DPLSS life cycle has been developed as a basis for the model. This CBS is used to address DPLSSs descriptively and nonnatively during LCVA evaluations.

A menu-driven computer program has also been developed to implement the DPLSS model on an IBM PC. This program leads users through the new LCVA-based methodology, performs economic and sensitivity analyses on their inputs, and then allows "what-if?â analyses on varying system configurations to be performed.

Master of Science

In this thesis, we propose to use Monte Carlo (MC) simulation to assess maintenance down time (MDT), which cannot be assessed a priori by traditional MIL-STD-471 (or now MIL-HDBK-470), at the early design phase based on various maintainability and provisioning options. Also, by using MC, we can perform a more rigorous in-progress maintainability demonstration during the design reviews. By following the MC approach in the MDT assessment at the early design phase, we can study the cost item related to revenue loss a prior for a commercial system design. This thesis proposes the use of MC simulation to estimate the MDT and thus the downtime-orientated profit loss along with other LCC items at the early design phase. This extends the US military standards to provide an accurate overall picture of a commercial system life cycle aspect for both the manufacturer and the user in performing integrated logistic support design trade-off at the early design phase. In order to stress the importance of this cost item about profit loss and keep the original military LCC structure undisturbed, we append the profit loss to the LCC and make a new economic trade-off factor, the "life cycle revenue loss" (LCRL). This definition of LCRL is stressed from the point of view of the user's life time. With a simple three-module water-level-control system, we demonstrate how to use MC in logistic trade-off problems based on LCC and LCRL at the early design phase. Our research shows that LCRL is more sensitive than LCC in handling a commercial system with profit concerns. We also develop a MC inventory trade-off approach based on LCRL and show that we may use the LCRL to integrate the concerns of the manufacturer and the user.

In dose-finding studies, c-optimal designs provide the most efficient design to study an interesting target dose. However, there is no guarantee that a c-optimal design that works best for estimating one specific target dose still performs well for estimating other target doses. Considering the demand in estimating multiple target dose levels, the robustness of the optimal design becomes important. In this study, the 4-parameter logistic model is adopted to describe dose-response curves. Under nonlinear models, optimal design truly depends on the pre-specified nominal parameter values. If the pre-specified values of the parameters are not close to the true values, optimal designs become far from optimum. In this research, I study an optimal design that works well for estimating multiple s and for unknown parameter values. To address this parameter uncertainty, a two-stage design technique is adopted using two different approaches. One approach is to utilize a design augmentation at the second stage, the other one is to apply a Bayesian paradigm to find the optimal design at the second stage. For the Bayesian approach, one challenging task is that it requires heavy computation in the numerical calculation when searching for the Bayesian optimal design. To overcome this problem, a clustering method can be applied. These two-stage design strategies are applied to construct a robust optimal design for estimating multiple s. Through a simulation study, the proposed two-stage optimal designs are compared with the traditional uniform design and the enhanced uniform design to see how well they perform in estimating multiple s when the parameter values are mis-specified.

This research effort examined the read rate differences in a passive ultra high frequency (UHF) Radio Frequency Identification (RFID) doorway portal as a function of antenna placement, doorway size and composition, reader manufacturer, tag type, and tag orientation. In this analysis of a RFID system, the response observations were modeled under an ordinal logistic regression model. The selection of a categorical analysis method was due to the flaws associated with the initial design of the experiment, which resulted in high valued observations which would have skewed the results of a quantitative model. The ordinal regression analysis of the data indicates that out of the parameters studied, system performance is increased when a Sirit reader system, setup in a double doorway, with an antenna at the top of the door frame as well as the sides are used in conjunction with Sirit NXP tags.

This dissertation is about 'transtructures', a term coined to describe new kinds of infrastructures that are more attentive and responsive to the needs of contemporary society, its emerging economies and technological capabilities. The purpose of this inquiry is to begin to explore the character and possibilities of a design practice that could guide responsibly and ethically the transition of existing industrial infrastructures towards these new configurations: what processes it could follow, and what materials it could include. Through a series of design experiments in the areas of logistics and telecommunications, I started to prototype and develop a programmatic framework for a 'redirective' design practice, which is aimed at engaging publics with infrastructural issues. Design probes and speculative mockups have been employed to express and materialize present and future infrastructural configurations, opening them up to public scrutiny and participation. The premise of this work is fairly simple: if we want to provide more citizen-centered solutions to emerging social demands, we need to explore what changes are possible, and even required, within the industrial systems that currently frame our possibilities for implementing such innovations. Thus, certain design interventions will be necessary to allow people outside these systems to understand and relate to these networks and to identify possibilities for their transformation. The result of this inquiry is the early 'prototype' of what a practice for redirecting and transitioning towards the design of such postindustrial infrastructures could be like. In particular, it exemplifies how design may inquire into the artificial space of industrial infrastructures and explore opportunities for their reconfiguration toward more contextually adaptive forms and functions.

The purpose with this thesis is to investigate how the logistic and the configuration of the terminal buildings and the perceptions of the passengers at Stockholm Arlanda Airport are related to each other, and what effect it has on the passengers and their traveling within the airport. The focus will be on the logistic at all four terminal buildings that is within the Airport. To create a perception of the logistic at the Airport and how it is related to the passengers perceptions, the investigators need to make knowledge of the terminal buildings, and thereby try to link the logistic with the perception of the experience room. Swedavia is the company that own, operate at and manage Stockholm Arlanda Airport. The investigators will make an interview with employees at Swedavia to get a more profound understanding of how the company is thinking about the logistic issues that they need to overlook. There will also be interviews with travelers to get their perception of the logistic, design and atmosphere at the Airport. Observations will also be made at various times at the Airport with focus on all of the terminal buildings.  The investigators use qualitative and quantitative methods to reach a result. To achieve a result, the investigators will use theories and scientific facts and other available facts that will be helpful to reach a result that will be analyzed.
Denna uppsats handlar om Stockholm Arlanda Airport och syftet med uppsatsen är att undersöka hur logistiken och utformningen i upplevelserummet hänger ihop, samt vilken påverkan detta har på resenärerna och resandet inom flygplatsen. Fokus kommer att läggas på logistiken i de fyra terminalbyggnaderna som finns inom flygplatsen. I undersökningen ses terminalbyggnaderna över för att skapa en uppfattning om logistiken och på så vis försöka koppla ihop logistiken med upplevelserummet. Swedavia är det företag som är verksam och driver Stockholm Arlanda Airport. Det är med de anställda inom Swedavia som intervjuer kommer att ske för att få en djupare förståelse hur företaget tänker i de logistikfrågor som eventuellt behöver ses över. Intervjuer kommer även att ske med resenärer för att få deras uppfattning om logistik, design och atmosfär inom flygplatsen. Förutom intervjuer kommer även observationer att genomföras på flygplatsen vid olika tillfällen och tider på dagen. De metoder som har använts i undersökningen för att komma fram till de resultat som behövs är kvalitativa och kvantitativa metoder. Detta uppnås genom att göra undersökningar i form av intervjuer, observationer, tillgänglig fakta, samt med hjälp av olika lämpliga teorier för att på bästa möjliga sätt komma fram till ett resultat som har analyserats fram.

The internationalisation of investments and the globalisation of the markets have created a high level of competition among manufacturing and services companies which has transcended the competition among nations. In this environment, quality information and exact timing are the sole answers for generating comparative and competitive advantages with respect to other manufacturers and providers. Inspired by these challenges, Latin American countries have searched for ways to increase and diversify their exports in order to heighten their trade balance surpluses. This, in turn, helps them to overcome their debt problems and gain access to a better quality of life. With these criteria in mind, these countries have begun to join the economic aperture and globalisation processes. United by their common ethnic heritage, they are driven by the growing need to co-ordinate national and regional decisions in order to achieve a harmonic community development. The efficiency principle imposed by the present international trade scenario requires extreme attention to detail in the administration of production costs and in placing products on the market. Because a product's success is highly sensitive to cost and distribution methods, maritime transport and its associated systems require very specific management techniques. Those management techniques must take into account that as transport is a service it gives added value to the cargo. Thus, the management model, costs involved, planning processes, and area policies are topics of vital importance for achieving these nations' development objectives. The design of specific policies, both operational as well as for development (investments), should comply with certain minimum conditions. The resulting policies should satisfy integrally and harmoniously the requirements the State establishes in its general National Development Strategy. This strategy considers factors of monetary and trade uncertainty. States must be particularly careful to interpret changes, tendencies, circumstances and difficulties which emerge in the international markets they serve, correctly. Therefore, the purpose of this study is to analyse the existing maritime transport logistic system in Chile, beginning with the history of ports and economic development. Subsequently, this study will analyse all relevant information related to logistics and the lessons learnt during the process of modernization. For analytical purposes, the study establishes an evaluation area which has been represented by a "graph" built up from nodes and links.These symbolise the complex network of port systems, hinterlands, roads, railways and coastal shipping. Likewise, the links and nodes have direction, intensity and values that the study intends to describe and evaluate. Moreover, hinterlands are not as exclusive as they were before. Consequently, most of the port systems face a very competitive market in offering services for international hinterlands/foreland. Therefore, this thesis will conclude that at least some Latin American countries establish land bridges between them. There have been some studies about the land bridges, "inter-oceanic corridors" or "integration corridors" options in South America.The Pacific Ocean Basin and the APEC countries represent a huge market for those Atlantic countries which have products to export and import from that vast area of the globe. The existence of the main industrial site of South America running from the Atlantic side of South America to the Pacific Coast, which forms an "Industrial Banana", is the foundation of a massive demand to and from both coasts. The study evaluated the logistics system through different criteria, such as logistics, physical capacities, and economic, social, environmental and political considerations. Having established these criteria, the researcher can better evaluate the relevant parameters and variables to consider in the design of the parametric model.
La internacionalizacion de las inversiones y la globalizacion de los mercados, han creado un alto nivel de competitividad entre los proveedores de manufactura o de servicios, lo que trasciende a la competitividad entre las naciones. En este escenario, la informacion de calidad y respuesta en tiempo real son la respuesta para generar ventajas comparativas y competitivas respecto de otros productores y proveedores. Inspirados en estos cambios, los paises Latinoamericanos han buscado formas como aumentar y diversificar sus exportaciones, con el proposito de incrementar sus balanzas comerciales. Esto les ayuda a sobrellevar sus problemas de deuda, accediendo a mejor calidad de vida. Con estos criterios en mente, los paises de la Region han accedido a los procesos de apertura economica y globalizacion de los mercados. Unidos por la herencia etnica comun, ven una creciente necesidad por la coordinacion de sus decisiones nacionales y regionales, de manera de alcanzar el desarrollo comun de manera harmonica. Los principios de eficiencia impuestos por el presente esquema de comercio internacional, requiren de una atencion especial en la gestion de los costos de produccion y en la colocacion de los productos en los mercados. Considerando que el exito del producto es sensible a su costo, los sistemas de distribucion y logistica requiren de tecnicas especificas de gestion. Por ello, los modelos de gestion, costos, procesos de planificacion y politicas sectoriales son de vital importancia para alcanzar los objetivos nacionales de desarrollo. El diseno de politicas sectoriales, tanto operacionales como de desarrollo (inversiones), deberian cumplir con los minimas condiciones para lograr su objetivo pais. Las politicas resultantes debieran satisfacer de manera integral y harmonica, los requirimientos que el Estado ha establecido en su Estrategia Nacional de Desarrollo. Dicha estrategia debe incluir las incertidumbres monetarias y de commercio. Los Estados deben ser particularmente cuidadosos para interpretar correctamente los cambios, tendencias, circunstancias y dificultades que emergen de los mercados internacionales que ellos sirven. Por lo indicado anteriormente, el proposito de esta tesis es analizar el sistema de logistica maritima en Chile, comenzando con la historia de sus puertos y desarrollo economico, posteriormente el analisis de la informacion relevante a logistica y las lecciones aprendidas durante el proceso de modernizacion economica. Con propositos analiticos, el estudio determino una zona fisica de evaluacion que esta representada por la "teoria de grafos". Esta simboliza la compleja red de puertos, hinterlands, caminos, ferrovias y transporte maritimo costero. Los nodos y sus enlaces tienen direccion, intensidad y valores que el estudio pretende evaluar y dimensionar. Mas aun, en la actualidad el hinterland de los puertos ha dejado de ser exclusivo, consecuentemente, los sistemas portuarios enfrentan una agresiva competencia para ofertar servicios a sus hinterland/foreland, por lo cual algunos paises latinoamericanos construyeron "puentes terrestres" entre ellos, el estudio indica algunas opciones de "puentes terrestres", "corredores inter-oceanicos" o "corredores de integracion" identificados en America del Sur. La cuenca del Pacifico y los paises APEC representan un mercado enorme para los paises de la costa Atlantica. La existencia de la principal area industrial de Sudamerica se configura entre el Atlantico y Pacifico, forma lo que el autor denomina como la "Banana Industrial", lo que origina una enorme demanda en los dos sentidos. El estudio evalua los sistemas desde diferentes criterios, tales como: sus capacidades fisicas y logisticas, sus consideraciones economicas, politicas, sociales, y medio ambientales. Una vez establesidos los criterios, el investigador puede identificar y evaluar de mejor forma los parametros y variables a considerar en el diseno del "modelo parametrico".

La logistique consiste à stocker, déplacer et expédier des marchandises à des détaillants ou clients finaux tant en garantissant une gestion efficace des flux d’information sous-jacents. Les travaux menés durant cette thèse visent à automatiser le processus de préparation de commande sur palette en introduisant des robots manipulateurs mobiles dans les entrepôts logistiques, avec un double objectif : diminuer la pénibilité du travail et augmenter la productivité face à la croissance des volumes traités.Après un état de l’art exhaustif sur les robots manipulateurs mobiles, l’auteur met en œuvre un ensemble de procédés et processus afin de prélever des colis sur des palettes disposées sous des racks et cela en toute autonomie. Des blocs fonctionnels sont ainsi constitués pour réaliser l’ensemble des tâches pour la base mobile (cartographie, localisation, planification, navigation) ainsi que pour le bras manipulateur. Une disposition originale et inédite des capteurs sur le manipulateur mobile ainsi que la mise en place d’ARtag sur les éléments d’infrastructures permettent de récupérer des « smart data » plutôt que du « big data », permettant de conjuguer la complexité du problème avec les contraintes temps réel de l’application.Un algorithme de suivi d’un « mur virtuel » est proposé utilisant une transformée de Hough rendue plus robuste grâce à plusieurs niveaux de filtrage. La synchronisation et la commande de ces deux systèmes est assurée par des réseaux de Pétri. Enfin le prototype développé durant cette thèse CIFRE a été non seulement testé au laboratoire mais aussi dans les conditions réelles d’un entrepôt logistique
Logistics involves the storage and displacement of goods. These goods are stored in warehouses and shipped to retailers in pallets. Pallets are produced on a customer’s order. Order picking for a pallet is a fatigue induced process resulting in poor performance of the workers, decreasing the productivity and inducing delays in supply chain. Flexibility is introduced to increase productivity by commissioning robots for process automation. These robots consist of autonomous ground vehicles for transporting freight and static manipulators for pick and place. A static robot has limited workspace and the capability of a manipulator is significantly enhanced by adding a mobile base. Mobile manipulation is now being exploited for pick & place and pallet production. This thesis presents a first attempt to achieve autonomous palletization using mobile manipulation. To acquire palletization by mobile manipulation requires the identification of functional blocks, to conceive a framework to achieve this task. A thorough state of the art has been prepared in this thesis corresponding to each element of the global framework. To realize the proof of concept, a prototype has been developed by leveraging existing technologies, by integrating a mobile base with manipulator and a grasping system with a gripping element. For each functional block of the global framework, control execution strategies have been developed and tested in industrial environment. Specifically, localization is acquired by the use of synthetic landmarks, a motion planning and control strategy is employed for global navigation and a rack tracking motion control has been developed for moving inside the racks. To combine and execute all the elements without deadlocks a coordination framework is used as a global supervisor. The path planner for global navigation is based on the shortest distance between two points, and rack tracking is developed by applying the conventional Hough transform to the lidar data and using the output in a nonlinear controller, while the motion planner for manipulation is based on linear trajectories. The framework for supervisory control is based on discrete event systems topology and state machines corresponding to each element have been modelized using Petri nets. Finally, the framework has been tested for a complete picking task on the mobile manipulator to validate the selection of strategies and performance of each functional element. The successful demonstration has been concluded as a first step towards the evolution of autonomous palletization

Maltreatment affected an estimated 794,000 children in the 50 States, the District of Columbia, and Puerto Rico in 2007 (United States Department of Health and Human Services [USDHHS], 2009). The purpose of this study was to examine the risk factors of young maternal age, parents' marital status, multiple birth, preterm birth, birth defects/disability, low economic status, and parental substance abuse related to suspected maltreatment of children 3 years of age or younger from the prospective of pediatric nurse practitioners (PNPs). A cross-sectional survey design, using the Tailored Design Method, was used in this study. A convenience sample consisting of the National Association of Pediatric Nurse Practitioners (NAPNAP) email registry was used for this study with a response rate of 11%. The respondents represented all regions of the United States. Seventy-nine percent of the PNP's (n=363) who completed the survey had suspected child abuse or neglect within the last year in a child three years of age or younger compared to 21% of PNPs (n=96) who did not suspect child maltreatment within the past year. The prevalence of suspected child maltreatment in the study population was 2.35%. According to the model examining child risk factors and abuse, the log of the odds of a child being abused was negatively related to preterm birth (p = .036) and birth defects/disability (p = .001). Multiple birth was positively related but not significant (p = .359). There were no statistically significant child risk factors found in the logistical regression for neglect (preterm birth, p = .180; multiple births, p = .938; birth defects/disabilities, p = .234). When examining the abuse and neglect groups together, the log of the odds of a child being abused and neglected was negatively related to birth defects/disabilities (p = .030). Preterm birth (p = .364) and multiple birth (p = .298) were positively related to the abuse and neglect group but were not significant. According to the model examining parental risk factors and abuse, the log of the odds of a child being abused due to a parent characteristic was negatively related to low economic status, with the proxy being WIC eligibility (p = .001) and a history of substance abuse (p = .031). The regression for abuse indicated a positive, yet insignificant, relationship with young maternal age (p = .129) and single marital status (p = .816). The logistic regression for neglect indicated a positive significant relationship with a substance abuse history (p = .012). The regression for neglect indicated positive but insignificant relationships for young maternal age (p = .693), marital status (p = .343), and WIC eligibility (p = .106). There were no statistically significant parental risk factors found in the logistical regression for abuse and neglect together (young maternal age, p = .263; marital status, p = .523; WIC eligibility, p = .131; substance abuse, p = .985). Findings indicated that child maltreatment is suspected by PNPs in primary care settings, and that PNPs recognize signs and symptoms of abuse and neglect.

Timetable development and design is a complex process that is crucial for safe and efficient railway operations. The combination of steel wheels and steel rails makes it possible to create trains and to transport many vehicles, thus passengers and freight, at the same time, but it also results in longer braking distances. These braking distances often exceed sight distance, which means that sufficient distance between trains must be maintained. This requires a thorough planning of train movements in order to prevent conflicting train paths and trains stopping for red signals. This is done by creating a time schedule for different train paths along the track, the so-called timetable. The timetable forms the backbone of railway operations, because a timetable informs a passenger when a train departs and arrives. However, in order to attract passengers, the timetable should be aligned with customer demand. Unfortunately, railway operation tends to deal with great demand variations over time and within the network. In order to make clear how passenger demand is distributed, the demand is often expressed in an origin-destination matrix. Each cell of the matrix corresponds to the number of expected passengers between an origin and destination. Based upon the demand distribution, a line design is created. A line design determines the route of a train, and consists of a stopping pattern and frequency per train. Although the line plan is important for the timetabling process, an optimal line plan does not automatically result in an optimal or feasible timetable. In the past, timetable design focused on a minimisation of the total travel time in conflict-free timetables only. Nevertheless, several studies confirmed the need for periodic and symmetric timetables that come with equal levels of service throughout the day, which are easily memorisable for the passenger. These timetables must be robust, so that a high punctuality can be achieved. Additionally, an ideal timetable also takes into account factors like in-vehicle time, waiting time and number of transfers, summarised in the perceived travel time (PTT). It is, however, impossible to include all these elements in a manual timetable design. This emphasises the need for a timetabling model that combines passenger demand and line design to calculate a timetable with a minimal PTT. Several different timetable models have been developed in the past, where each model has its own area of focus. Some models focus on the optimisation of line plans, so that the line design connects most important origin-destination pairs and travel time between these pairs is minimised. However, these models do not take into account specific arrival and departure times. It might thus be that the travel time will be high for passengers that have to change trains. Other models focus on the development of conflict-free timetables, in which the infrastructure governs the timetable. Although this might result in a feasible timetable, it may not always be an optimal timetable since passenger demand is often not included. The final category of timetabling models focuses on the improvement of passenger satisfaction. These models minimise waiting time or the total journey time for instance. Nevertheless, the resistance to change trains is usually high, but often not included in the calculation. In contrary to other timetabling models, the Strategic Passenger Oriented Timetabling (SPOT) model, developed by Polinder (2020) and NS, is able to create a timetable with a minimal PTT. However, the model is currently not used within the timetable development process. Therefore, this research has investigated to what extent the SPOT model can be used in this process, and hence support and speed up the design of new timetables. The SPOT model includes the resistance to change trains in the calculation of the PTT. In the model it is assumed that each minute of in-vehicle time counts as 1 passenger-minute, each minute of waiting time corresponds to 2 passenger-minutes, and each transfer is awarded with a penalty of 20 passenger-minutes. A lower PTT is thus achieved through an optimisation of waiting times and transfer penalties. It means that the model can especially be used for determining arrival and departure times at transfer nodes. Despite the fact that the model is unable to include infrastructural limitations, the results are useful for determining which transfer possibilities are important at each node. In order to validate this hypothesis, two case studies have been performed for the transfernodes Weesp and Zwolle. These cases have been selected based upon recent problems during the development of post-COVID-19 timetable scenarios for NS. For each casestudy, several elements of the current timetable and proposed scenarios have been included in the input of the model, in order to analyse the effect on the timetable at the specific node. The output of the model, consisting of the PTT, improvement potentials for origin-destination pairs and dwell-time graphs, provided a clear overview of how each experiment scored. In the end, this study concludes that the SPOT model is especially applicable for studies in which different timetable scenarios must be compared with each other. It can help to illustrate the impact of decisions and trade-offs, so that different ideas on timetable design can be assessed before making specific, conflict-free timetables. The model can thus be used in the stage of exploratory research.
Tidtabellsutveckling är en komplex process som är avgörande för en säker och effektiv järnvägsdrift. Kombinationen av stålhjul och stålräl gör det möjligt att skapa tåg och transportera många vagnar, med passagerare eller gods, samtidigt, men det leder också till längre bromssträckor. Dessa bromssträckor överskrider ofta siktavståndet, vilket innebär att tillräckligt avstånd mellan tågen måste bibehållas. Detta kräver en grundlig planering av tågrörelser för att förhindra motstridiga tågvägar. Detta görs genom att skapa ett tidsschema för olika tåg längs spåret, den så kallade tidtabellen. Tidtabellen utgör ryggraden i järnvägsverksamheten, eftersom en tidtabell informerar en passagerare när ett tåg avgår och anländer. För att attrahera passagerare bör tidtabellen dock anpassas till kundernas efterfrågan. Tyvärr tenderar järnvägsoperationer att hantera stora efterfrågevariationer över tid och inom nätverket. För att klargöra hur passagerarefterfrågan fördelas uttrycks efterfrågan ofta i en matris för ursprungsdestination. Varje cell i matrisen motsvarar antalet förväntade passagerare mellan ett ursprung och en destination. Baserat på efterfrågefördelningen skapas ett linjeupplägg. Ett linjeupplägg bestämmer tågets rutt och består av ett stoppmönster och frekvens per tåg. Även om linjeplanen är viktig för tidtabellprocessen, resulterar ett optimalt linjeupplägg inte automatiskt i en optimal eller genomförbar tidtabell. Tidigare fokuserade tidtabellsutformningen på att minimera den totala restiden endast i konfliktfria tidtabeller. Ändå har flera studier bekräftat behovet av periodiska och symmetriska tidtabeller som har samma servicenivåer hela dagen och som är lätta att minnas för passageraren. Dessa tidtabeller måste vara robusta så att en hög punktlighet kan uppnås. Dessutom tar en ideal tidtabell också hänsyn till faktorer som fordonstid, väntetid och antal byten, sammanfattade i den upplevda restiden (PTT). Det är dock omöjligt att inkludera alla dessa element i en manuell tidtabellsplanering. Detta betonar behovet av en tidtabellsmodell som kombinerar passagerares efterfrågan och linjeupplägg för att beräkna en tidtabell med minimal PTT. Flera olika tidtabellmodeller har utvecklats tidigare, där varje modell har sitt eget fokusområde. Vissa modeller fokuserar på optimering av linjeplaner, så att linjeupplägget ansluter de viktigaste ursprung-destinationsparen och att restiden mellan dessa par minimeras. Dessa modeller tar dock inte hänsyn till specifika ankomst- och avgångstider. Det kan alltså vara så att restiden blir hög för passagerare som måste byta tåg. Andra modeller fokuserar på utvecklingen av konfliktfria tidtabeller, där infrastrukturen styr tidtabellen. Även om detta kan resultera i en genomförbar tidtabell, kanske det inte alltid är en optimal tidtabell eftersom passagerarefterfrågan ofta inte ingår. Den sista kategorin av tidtabellmodeller fokuserar på förbättring av passagerarnöjdheten. Dessa modeller minimerar till exempel väntetiden eller den totala restiden. Ändå är motståndet mot tågbyte ofta högt, men ingår inte i beräkningen. I motsats till andra tidsplaneringsmodeller kan SPOT-modellen, utvecklad av Polinder (2020) och NS (den största persontågsoperatören i Nederländerna), skapa en tidtabell med minimal PTT. I denna beräkning ingår motståndet mot byte av tåg. I modellen antas att varje minut i fordonstiden räknas som 1 passagerarminut, varje minut väntetid motsvarar 2 passagerarminuter och varje byte tilldelas ett straff på 20 passagerarminuter. En lägre PTT uppnås således genom en optimering av väntetider och överföringsstraff. Det betyder att modellen särskilt kan användas för att bestämma ankomst- och avgångstider vid överföringsnoder. Trots det faktum att modellen inte kan inkludera infrastrukturella begränsningar är resultaten användbara för att bestämma vilka bytesmöjligheter som är viktiga vid varje nod. För att validera denna hypotes har två fallstudier utförts för bytesnoderna Weesp och Zwolle. Dessa fall har valts ut baserat på de senaste problemen under utvecklingen av tidtabellsscenarier efter COVID-19 för NS. För varje fallstudie har flera delar av den aktuella tidtabellen och föreslagna scenarier inkluderats som indata till modellen för att analysera effekten på tidtabellen vid den specifika noden. Utdata fran modellen, bestående av PTT, förbättringspotentialer för par ursrungs- och detinationspar och grafer för uppehållstid gav en tydlig översikt över resultatet från varje experiment. Slutligen drar denna studie slutsatsen att SPOT-modellen är särskilt användbar för studier där olika tidtabeller måste jämföras med varandra. Den kan hjälpa till att visa effekterna av beslut och kompromisser, så att olika idéer om tidtabellsupplägg kan utvärderas innan man gör specifika, konfliktfria tidtabeller. Modellen kan alltså användas i ett tidigt skede.
Het ontwikkelen en ontwerpen van dienstregelingen is een complex proces dat cruciaal is voor een veilig en efficiënt vervoer per spoor. De combinatie van stalen wielen op stalen spoorstaven zorgt ervoor dat het mogelijk is om meerdere voertuigen te combineren en treinen samen te stellen, en zodoende veel reizigers of goederen op hetzelfde moment te verplaatsen. Echter, de combinatie van staal op staal zorgt ook voor lange remwegen. Doordat deze remwegen de zichtafstand vaak overschrijden, moet er gewaarborgd worden dat treinen altijd op voldoende afstand van elkaar rijden. Hiervoor is een strakke en uitvoerige planning benodigd, waardoor conflicten worden voorkomen en treinen niet voor een rood sein tot stilstand komen. Deze planning definieert voor elke trein het tijdspad over een bepaald traject, de zogenaamde dienstregeling. De dienstregeling vormt de ruggengraat van de treindienst, onder andere omdat deze de reizigers informeert wanneer een trein vertrekt en aankomt. Echter, om reizigers te werven is het belangrijk dat de dienstregeling overeenkomt met datgene wat de reiziger wil. Het nadeel is dat vervoer per spoor vaak te maken heeft met een variërende vraag. Om inzicht te geven hoe deze reizigersvraag zich verhoudt tot het netwerk, wordt de reizigersvraag vaak uitgedrukt in een herkomst-bestemmingsmatrix. Elke cel in de matrix correspondeert met het aantal verwachte reizigers tussen een specifieke vertrek- en aankomstlocatie. Op basis van de verdeling van de reizigersvraag wordt vervolgens een lijnvoeringsontwerp gemaakt. De lijnvoering bepaalt de route, frequentie en het stoppatroon van een trein. Hoewel een lijnvoering belangrijk is in het ontwerpproces, garandeert een optimale lijnvoering niet automatisch een optimale dienstregeling. In het verleden werd er bij het maken van het dienstregelingsontwerp vooral gefocust op het minimaliseren van de pure reistijd binnen een conflictvrije dienstregeling. Meerdere studies hebben echter aangetoond dat de reiziger vooral behoefte heeft aan een repeterende en symmetrische dienstregeling, waarbij de reiziger de dienstregeling eenvoudig kan onthouden en de reiskwaliteit constant is. Deze dienstregeling moet robuust zijn, zodat een hoge punctualiteitsgraad behaald kan worden. Bovendien richt het ontwerp zich niet enkel op het minimaliseren van de pure reistijd, maar wordt er gekeken naar het totaalplaatje van in-treintijd, wachttijd en aantal keer overstappen. Dit is de zogenaamde gegeneraliseerde reistijd (GRT). In een handmatig ontworpen dienstregeling is het onmogelijk om al deze factoren in acht te nemen. Er is dan ook behoefte aan een dienstregelingsmodel dat reizigersvraag en lijnvoering combineert, zodat een ontwerp gemaakt kan worden waarbij de GRT wordt geminimaliseerd. Door de jaren heen zijn er diverse modellen ontwikkeld, waarbij de meeste modellen zich richten op een specifiek onderdeel van het dienstregelingsprobleem. Sommige modellen hebben als doel om de lijnvoering te optimaliseren, zodat het ontwerp altijd de belangrijkste herkomsten en bestemmingen met elkaar verbindt. Een nadeel is dat op dit niveau er nog geen specifiek vertrek- en aankomsttijden bepaald kunnen worden, waardoor uiteindelijk de reistijd enorm kan toenemen voor reizigers die moeten overstappen. Andere modellen focussen juist op het genereren van conflictvrije dienstregelingen, waarbij de aanwezige infrastructuur leidend is voor de dienstregeling. Hoewel dit de uitvoerbaarheid van de dienstregeling garandeert, is dit veelal niet de meest wenselijke dienstregeling omdat de reizigersvraag hierin niet wordt meegenomen. Tenslotte zijn er modellen die de klantbeleving proberen te verbeteren door bijvoorbeeld de totale wacht- of reistijd te minimaliseren. Desalniettemin is hierin de weerstand om over te stappen vaak niet inbegrepen, terwijl dit wel van grote invloed kan zijn. In tegenstelling tot andere modellen is het door Polinder (2020) en NS ontwikkelde SPOTmodel in staat om een dienstregeling te berekenen met een minimale GRT en dus tot een beter ontwerpvoorstel te komen. Echter, het SPOT model wordt momenteel nog niet gebruikt in het daadwerkelijke dienstregelingsontwerpproces. Dit onderzoek richt zich daarom op de vraag in hoeverre het SPOT model kan worden gebruikt bij het ontwerpen van nieuwe dienstregelingen, en zodoende het proces te ondersteunen en te versnellen. In de berekening van de GRT is de weerstand om over te stappen inbegrepen. In het model wordt aangenomen dat elke minuut aan in-treintijd telt voor 1 reizigersminuut, elke minuut aan wachttijd telt voor 2 reizigersminuten, en er voor elke overstap een boete van 20 reizigersminuten wordt opgelegd. Een lagere GRT wordt dus behaald bij het optimaliseren van de wachttijd en het aantal overstapboetes. Dit betekent dat het model gebruikt kan worden voor het bepalen van de ideale aankomst- en vertrektijden op overstapstations. Hoewel het SPOT-model geen rekening houdt met infrastructurele beperkingen, kunnen de resultaten worden gebruikt om per station te bepalen welke overstaprelaties van belang zijn. Om deze hypothese te bevestigen zijn in dit onderzoek twee experimenten uitgevoerd voor de overstapstations Weesp en Zwolle. Deze locaties zijn gekozen op basis van recente studies binnen NS op het gebied van een post-corona dienstregeling. Voor elk experiment zijn bepaalde elementen van de huidige dienstregeling alsmede van de voorgestelde post-corona dienstregeling in het model geladen. Op deze manier kunnen de effecten op de dienstregeling voor de specifieke locatie in kaart worden gebracht en geanalyseerd. De uitkomsten van het model bestaan uit de GRT, verbeterpotentie per herkomst-bestemmingspaar en halteertijdgrafieken, welke vervolgens een duidelijk beeld geven van hoe ieder experiment scoort. Uiteindelijk is op basis van deze experimenten geconcludeerd dat het SPOT-model geschikt is voor langetermijnstudies waarbinnen verschillende dienstregelingsvoorstellen met elkaar moeten worden vergeleken. Het model kan daarbij inzicht bieden in de impact en afwegingen die in het ontwerp gemaakt moeten worden. Op deze manier kunnen verschillende gedachtegangen al beoordeeld worden voordat er een gedetailleerde, conflictvrije dienstregeling ontworpen wordt. Daarmee is het model dus toepasbaar in de fase van het verkennend dienstregelingsonderzoek.

Orientadores: Takaaki Ohishi, Anibal Tavares de Azevedo
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
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Resumo: A cadeia de exportação da soja tem alta participação no desempenho econômico do país. No entanto, as principais áreas produtoras são expostas a diversos problemas logísticos decorrentes da falta de planejamento e de investimentos em infraestrutura. Como resultado, os produtores são onerados pelos custos diminuindo seu capital disponível para investimentos, o que compromete as safras futuras e a projeção econômica do país. Diante desta realidade o governo brasileiro tem tomado medidas e realizando investimentos para sanar estes problemas. Os investimentos realizados em infraestrutura devem ser planejados para o longo prazo. Deste modo, este trabalho propõe a análise de um modelo capacitado de design de rede de hubs e, posteriormente, com base no mesmo, desenvolve três de modelos matemáticos que descrevem a cadeia exportação da soja e suas especificidades a fim de, criar uma ferramenta de análise para definir a localização de facilidades, armazenadoras/ consolidadoras/ redirecionadoras de fluxo, as rotas a serem utilizadas e a utilização dos portos para otimizar esta cadeia. Para aplicar os modelos, o Estado do Mato Grosso foi selecionado como foco do estudo., e com base no qual, foi realizado um extenso levantamento de dados da soja. Considerando que o Estado do Mato Grosso é dividido em 22 microrregiões foram esti-madas a quantidade de soja produzida, identificada a quantidade de soja exportada e a capacidade estática de cada microrregião. Também foram identificados os principais países importadores da soja brasileira e os principais portos de exportação, além das quantidades de soja exportada para cada país, a utilização atual dos portos e identificação das rotas terrestres e marítimas utilizadas no transporte
Abstract: The soybean exporter chain has high participation in the economic performance of the country. However, the main producing areas are exposed to several logistical problems arising from lack of planning and investment in infrastructure. As a result, producers are burdened by the costs and have an available capital decrease to future investments, which reduce futures crops and future economic potential of the country. Faced with this reality, the Brazilian government has taken measures and investing to solve these problems. Investments in infrastructure should be planned for the long term. Thus, this paper proposes the analysis of a capacitated model design of network hubs and then, based on it, develops three mathematical models that describe the soybeans exporter chain, in order to create an analysis tool to define the location of facilities, as storage / switching / transshipment facilities, define routes and ports that should be utilized to optimize the use of the chain. In order to apply the model, the state of Mato Grosso was selected as the focus of this study and, based on which, an extensive survey data of soybeans was realized. Whereas that the State of Mato Grosso is divided into 22 micro regions it was estimated their soybeans production, identified the amount of soybeans exported and the static capacity to each one. The main importer¿s countries of Brazilian soybeans and the major export ports it was also identified, in addition, the amounts of soybeans exported by each country and ports, and identification of routes and sea routes used to transport
Doutorado
Automação
Doutora em Engenharia Elétrica

Statistics
Ph.D.
Sigmoid curves have found broad applicability in biological sciences and biopharmaceutical research during the last decades. A well planned experiment design is essential to accurately estimate the parameters of the model. In contrast to a large literature and extensive results on optimal designs for linear models, research on the design for nonlinear, including sigmoid curve, models has not kept pace. Furthermore, most of the work in the optimal design literature for nonlinear models concerns the characterization of minimally supported designs. These minimal, optimal designs are frequently criticized for their inability to check goodness of fit, as there are no additional degrees of freedom for the testing. This design issue can be a serious problem, since checking the model adequacy is of particular importance when the model is selected without complete certainty. To assess for lack of fit, we must add at least one extra distinct design point to the experiment. The goal of this dissertation is to identify optimal or highly efficient designs capable of checking the fit for sigmoid curve models. In this dissertation, we consider some commonly used sigmoid curves, including logistic, probit and Gompertz models with two, three, or four parameters. We use D-optimality as our design criterion. We first consider adding one extra point to the design, and consider five alternative designs and discuss their suitability to test for lack of fit. Then we extend the results to include one more additional point to better understand the compromise among the need of detecting lack of fit, maintaining high efficiency and the practical convenience for the practitioners. We then focus on the two-parameter Gompertz model, which is widely used in fitting growth curves yet less studied in literature, and explore three-point designs for testing lack of fit under various error variance structures. One reason that nonlinear design problems are so challenging is that, with nonlinear models, information matrices and optimal designs depend on the unknown model parameters. We propose a strategy to bypass the obstacle of parameter dependence for the theoretical derivation. This dissertation also successfully characterizes many commonly studied sigmoid curves in a generalized way by imposing unified parameterization conditions, which can be generalized and applied in the studies of other sigmoid curves. We also discuss Gompertz model with different error structures in finding an extra point for testing lack of fit.
Temple University--Theses

This thesis investigates how gesture-driven interfaces, integrated in HMD- based (Head-Mounted Display) Augmented Reality (AR) devices can be used in the context of order picking processes in logistic warehouses as a substitute to existing solutions for visualisation and interaction with order picking lists: which hand gestures should be used? What qualities are essential for designing a successful substitute? By applying an User-Centered Design approach, generative ideation methodologies, prototyping and usability testing this research results in a contribution to a framework of design guidelines for designing gesture-driven AR in the order picking process, as well as a proposition of a gestural interaction language grounded in both earlier research and empirical findings. The empirical findings include details of the end users’ gestural interaction preferences and content-related considerations, which was implemented in a low fidelity prototype and evaluated in the contextual domain of the end users.

Globalization that diminishes the barriers to trade worldwide has transformed the structure of production and increased the global competition in the textile and apparel industry. Especially, the elimination of quotas on January 2005 has totally changed the whole scenario of the apparel industry. A boom has been noticed in the emerging markets. Buyers shift their maximum orders to the low cost countries to increase their profit margins. China has gained its popularity among the European and American buyers because of the cheap labor and large scales of production and has become the world’s largest exporter of textile and apparel. The traditional competitive factor among the buyers is the lower cost of the product but the changing markets trends and demand volatility pushes the buyers to focus also on quality and lead times in addition to price. Due to the huge competition among the cluster of brands, retailers and wholesalers, lead time is becoming critical as longer lead times increases the risk of bottleneck to sales. China is the most important apparel supplier for the EU (especially Germany, the UK, and France) because it provides the cost benefit to the sourcing companies, but at the same time, it increases the lead times and also has more environmental impact in terms of pollution because of the long geographical distance.This thesis highlights that there is a remarkable rise of the labor cost in China, noticed for the last couple of years, which has reduced the competitive factor of price while sourcing from China. This is also an upcoming challenge for the whole world with regards to sourcing strategies. Many sourcing companies are shifting their shares away from China in order to achieve their desired profit margins. Turkey may be an alternative sourcing destination for the European apparel buyers and wholesalers because of its competitive labor cost, favorable government policies, flexibility, sustainability, and proximity to Europe. In this thesis, a pilot study is carried out to determine the relationship and effects of lead times on sales. This thesis also describes the effects of relationships among the business partners on the supply chain flow. It is noted through several pilot studies that the organizations who work in collaboration with their supply chain partners can significantly improve their supply chain efficiency by reducing the inventories, markdowns, lead times, lost sales, and increasing forecast accuracy. There are several tools in use for collaboration such as Vendor Managed Inventory (VMI), Electronic Data Interchange (EDI), Just in Time (JIT), Customer Relationship Management (CRM), and Collaboration, Planning, Forecasting, and Replenishment (CPFR). In this paper the CPFR implementation steps, benefits, and hindrances are discussed in detail.
Program: Master programme in Applied Textile Management

This research addresses the novel application of design of experiment, artificial neural net-works and logistic regression to study the effect of demographic characteristics on the risk of acquiring HIV infection among the antenatal clinic attendees in South Africa. The annual antenatal HIV survey is the only major national indicator for HIV prevalence in South Africa. This is a vital technique to understand the changes in the HIV epidemic over time. The annual antenatal clinic data contains the following demographic characteristics for each pregnant woman; age (herein called mother's age), partner's age (herein father's age), population group (race), level of education, gravidity (number of pregnancies), parity (number of children born), HIV and syphilis status. This project applied a screening design of experiment technique to rank the effects of individual demographic characteristics on the risk of acquiring an HIV infection. There are a various screening design techniques such as fractional or full factorial and Plackett-Burman designs. In this work, a two-level fractional factorial design was selected for the purposes of screening. In addition to screening designs, this project employed response surface methodologies (RSM) to estimate interaction and quadratic effects of demographic characteristics using a central composite face-centered and a Box-Behnken design. Furthermore, this research presents the novel application of multi-layer perceptron’s (MLP) neural networks to model the demographic characteristics of antenatal clinic attendees. A review report was produced to study the application of neural networks to modelling HIV/AIDS around the world. The latter report is important to enhance our understanding of the extent to which neural networks have been applied to study the HIV/AIDS pandemic. Finally, a binary logistic regression technique was employed to benchmark the results obtained by the design of experiments and neural networks methodologies. The two-level fractional factorial design demonstrated that HIV prevalence was highly sensitive to changes in the mother's age (15-55 years) and level of her education (Grades 0-13). The central composite face centered and Box-Behnken designs employed to study the individual and interaction effects of demographic characteristics on the spread of HIV in South Africa, demonstrated that HIV status of an antenatal clinic attendee was highly sensitive to changes in pregnant mother's age and her educational level. In addition, the interaction of the mother's age with other demographic characteristics was also found to be an important determinant of the risk of acquiring an HIV infection. Furthermore, the central composite face centered and Box-Behnken designs illustrated that, individual-ally the pregnant mother's parity and her partner's age had no marked effect on her HIV status. However, the pregnant woman’s parity and her male partner’s age did show marked effects on her HIV status in “two way interactions with other demographic characteristics”. The multilayer perceptron (MLP) sensitivity test also showed that the age of the pregnant woman had the greatest effect on the risk of acquiring an HIV infection, while her gravidity and syphilis status had the lowest effects. The outcome of the MLP modelling produced the same results obtained by the screening and response surface methodologies. The binary logistic regression technique was compared with a Box-Behnken design to further elucidate the differential effects of demographic characteristics on the risk of acquiring HIV amongst pregnant women. The two methodologies indicated that the age of the pregnant woman and her level of education had the most profound effects on her risk of acquiring an HIV infection. To facilitate the comparison of the performance of the classifiers used in this study, a receiver operating characteristics (ROC) curve was applied. Theoretically, an ROC analysis provides tools to select optimal models and to discard suboptimal ones independent from the cost context or the classification distribution. SAS Enterprise MinerTM was employed to develop the required receiver-of-characteristics (ROC) curves. To validate the results obtained by the above classification methodologies, a credit scoring add-on in SAS Enterprise MinerTM was used to build binary target scorecards comprised of HIV positive and negative datasets for probability determination. The process involved grouping variables using weights-of-evidence (WOE), prior to performing a logistic regression to produce predicted probabilities. The process of creating bins for the scorecard enables the study of the inherent relationship between demographic characteristics and an in-dividual’s HIV status. This technique increases the understanding of the risk ranking ability of the scorecard method, while offering an added advantage of being predictive.

In this study I examine voter response at an interview level using a dataset of 7562 voter contacts (including responses and nonresponses) in the 2004 Utah Colleges Exit Poll. In 2004, 4908 of the 7562 voters approached responded to the exit poll for an overall response rate of 65 percent. Logistic regression is used to estimate factors that contribute to a success or failure of each interview attempt. This logistic regression model uses interviewer characteristics, voter characteristics (both respondents and nonrespondents), and exogenous factors as independent variables. Voter characteristics such as race, gender, and age are strongly associated with response. An interviewer's prior retail sales experience is associated with whether a voter will decide to respond to a questionnaire or not. The only exogenous factor that is associated with voter response is whether the interview occurred in the morning or afternoon.

Nesta tese propõe-se um método heurístico para o problema de Projeto de Rede da Cadeia de Suprimentos (Supply Chain Network Design) considerando vários aspectos de relevância prática, tais como: fornecedores e matérias-primas, localização e operação de instalações, atribuição de Centros de Distribuição (CD), e grande número de clientes e produtos. Uma eficiente abordagem heurística de duas fases é proposta para a obtenção de soluções viáveis para os problemas, que inicialmente é modelado como um Programa Linear Inteiro Misto (PLIM) de grande escala. Na fase de construção, uma estratégia de Linear Programming Rounding é aplicada para se obter os valores iniciais para as variáveis de localização inteira do modelo. Simultaneamente, um método Multi-start foi desenvolvido para gerar soluções iniciais diversificadas para cada nova iteração da heurística de Rounding. Na segunda fase, dois procedimentos de Busca Local foram desenvolvidos no sentido de melhorar a solução fornecida pelo método de Rounding. Implementamos duas diferentes abordagens de Busca Local: remoção-inserção e troca. Uma técnica de Busca Tabu para orientar o procedimento de Busca Local para explorar os diferentes espaços de soluções foi desenvolvida. As formulações e algoritmos foram implementados na linguagem C++ utilizando ferramentas de otimização da COIN-OR. O método de solução foi experimentado em instâncias geradas aleatoriamente, com tamanhos diferentes em termos do número de parâmetros, tais como o número de produtos, zonas de clientes, CDs e fábricas considerando um sistema logístico de quatro níveis. As implementações computacionais mostram que o método de solução proposto obteve resultados satisfatórios quando comparados com a literatura. Para validar este método heurístico também foi usado em um caso realista, com base em dados de uma empresa de borracha que está reestruturando sua cadeia de suprimentos devido ao projeto de uma nova uma nova fábrica e produção de novos produtos. A abordagem heurística proposta revelou-se adequada para aplicação prática em um caso real de uma indústria multicommodity em um contexto determinístico.
In this thesis we propose a heuristic method for the Supply Chain Network Design (SCND) problem considering several aspects of practical relevance: suppliers and raw materials, location and operation facilities, distribution center (DC) assignments, and large numbers of customers and products. An efficient two-phase heuristic approach is proposed for obtaining feasible solutions to the problems, which is initially modeled as a large-scale Mixed Integer Linear Program (MILP). In the construction phase, a linear programming rounding strategy is applied to obtain initial values for the integer location variables in the model. Simultaneously, a Multi-start method was developed to generate diversified initial solutions from each new iteration in the rounding heuristic. In the second phase, two Local Search procedures were developed towards to improve the solution provided by the rounding method. We implemented two different Local Search approaches: removal-insertion and exchange. A Tabu Search technique was developed to guide the Local Search procedure to explore the different spaces of solutions. The formulations and algorithms were implemented in C++ code language using the optimization engine COIN-OR. The solution method was experimented in randomly generated instances, with different sizes in terms of the number of parameters, such as number of products, customer zones, DCs, and factories considering a four-echelon logistic system. The computational implementations show that the solution method proposed obtained satisfactory results when compared to the literature review. To validate this heuristic method was also used in a realistic case, based on data from a rubber company that is restructuring its supply chain due to the overture of a new factory, producing new products. The proposed heuristic approach proved appropriate to practical application in a realistic case of a multi commodity industry in a deterministic context.

The California Department of Transportation (Caltrans) seismic bridge design process for an Ordinary Bridge described in the Seismic Design Criteria (SDC) directs the design engineer to meet minimum requirements resulting in the design of a bridge that should remain standing in the event of a Design Seismic Hazard. A bridge can be designed to sustain significant damage; however it should avoid the collapse limit state, where the bridge is unable to resist loads due to self-weight. Seismic hazards, in the form of a design spectrum or ground motion time histories, are used to determine the demands of the bridge components and bridge system. These demands are compared to the capacity of the components to ensure that the bridge meets key performance criteria. The SDC also specifies design detailing of various components, including abutments, foundations, hinge seats and bent caps. The expectation of following the guidelines set forth by the SDC during the design process is that the resulting bridge design will avoid collapse under anticipated seismic loads. While the code provisions provide different analyses to follow and component detailing to adhere to in order to ensure a proper bridge design, the SDC does not provide a way to quantitatively determine whether the bridge design has met the requirement of no-collapse. The objectives of this research are to introduce probabilistic fragility analysis into the Caltrans design process and address the gap of information in the current design process, namely the determination of whether the bridge design meets the performance criteria of no-collapse at the design hazard level. The motivation for this project is to improve the designer's understanding of the probabilistic performance of their bridge design as a function of important design details. To accomplish these goals, a new bridge fragility method is presented as well as a design support tool that provides design engineers with instant access to fragility information during the design process. These products were developed for one specific bridge type that is common in California, the two-span concrete box girder bridge. The end product, the design support tool, is a bridge-specific fragility generator that provides probabilistic performance information on the bridge design. With this tool, a designer can check the bridge design, after going through the SDC design process, to determine the performance of the bridge and its components at any hazard level. The design support tool can provide the user with the probability of failure or collapse for the specific bridge design, which will give insight to the user about whether the bridge design has achieved the performance objective set out in the SDC. The designer would also be able to determine the effect of a change in various design details on the performance and therefore make more informed design decisions.

Globalization that diminishes the barriers to trade worldwide has transformed the structure of production and increased the global competition in the textile and apparel industry. Especially, the elimination of quotas on January 2005 has totally changed the whole scenario of the apparel industry. A boom has been noticed in the emerging markets. Buyers shift their maximum orders to the low cost countries to increase their profit margins. China has gained its popularity among the European and American buyers because of the cheap labor and large scales of production and has become the world’s largest exporter of textile and apparel. The traditional competitive factor among the buyers is the lower cost of the product but the changing markets trends and demand volatility pushes the buyers to focus also on quality and lead times in addition to price. Due to the huge competition among the cluster of brands, retailers and wholesalers, lead time is becoming critical as longer lead times increases the risk of bottleneck to sales. China is the most important apparel supplier for the EU (especially Germany, the UK, and France) because it provides the cost benefit to the sourcing companies, but at the same time, it increases the lead times and also has more environmental impact in terms of pollution because of the long geographical distance.This thesis highlights that there is a remarkable rise of the labor cost in China, noticed for the last couple of years, which has reduced the competitive factor of price while sourcing from China. This is also an upcoming challenge for the whole world with regards to sourcing strategies. Many sourcing companies are shifting their shares away from China in order to achieve their desired profit margins. Turkey may be an alternative sourcing destination for the European apparel buyers and wholesalers because of its competitive labor cost, favorable government policies, flexibility, sustainability, and proximity to Europe. In this thesis, a pilot study is carried out to determine the relationship and effects of lead times on sales. This thesis also describes the effects of relationships among the business partners on the supply chain flow. It is noted through several pilot studies that the organizations who work in collaboration with their supply chain partners can significantly improve their supply chain efficiency by reducing the inventories, markdowns, lead times, lost sales, and increasing forecast accuracy. There are several tools in use for collaboration such as Vendor Managed Inventory (VMI), Electronic Data Interchange (EDI), Just in Time (JIT), Customer Relationship Management (CRM), and Collaboration, Planning, Forecasting, and Replenishment (CPFR). In this paper the CPFR implementation steps, benefits, and hindrances are discussed in detail.
Program: Master programme in Applied Textile Management

Doctor of Philosophy
Department of Physics
Dean Zollman
As part of a collaborative study of the science preparation of elementary school teachers, we investigated the quality of students’ reasoning and explored the relationship between sophistication of reasoning and the degree to which the courses were considered inquiry oriented. To probe students’ reasoning, we developed open-ended written content questions with the distinguishing feature of applying recently learned concepts in a new context. We devised a protocol for developing written content questions that provided a common structure for probing and classifying students’ sophistication level of reasoning. In designing our protocol, we considered several distinct criteria, and classified students’ responses based on their performance for each criterion. First, we classified concepts into three types: Descriptive, Hypothetical, and Theoretical and categorized the abstraction levels of the responses in terms of the types of concepts and the inter-relationship between the concepts. Second, we devised a rubric based on Bloom’s revised taxonomy with seven traits (both knowledge types and cognitive processes) and a defined set of criteria to evaluate each trait. Along with analyzing students’ reasoning, we visited universities and observed the courses in which the students were enrolled. We used the Reformed Teaching Observation Protocol (RTOP) to rank the courses with respect to characteristics that are valued for the inquiry courses. We conducted logistic regression for a sample of 18 courses with about 900 students and reported the results for performing logistic regression to estimate the relationship between traits of reasoning and RTOP score. In addition, we analyzed conceptual structure of students’ responses, based on conceptual classification schemes, and clustered students’ responses into six categories. We derived regression model, to estimate the relationship between the sophistication of the categories of conceptual structure and RTOP scores. However, the outcome variable with six categories required a more complicated regression model, known as multinomial logistic regression, generalized from binary logistic regression. With the large amount of collected data, we found that the likelihood of the higher cognitive processes were in favor of classes with higher measures on inquiry. However, the usage of more abstract concepts with higher order conceptual structures was less prevalent in higher RTOP courses.

Através dos dispositivos e técnicas desenvolvidas na área da Instrumentação Biomédica é possível oferecer um tratamento ou de forma geral soluções que permitam uma vivência mais plena em sociedade para pessoas que possuem algum tipo de deficiência ou doença. Com o aumento da capacidade computacional nos últimos anos foi possível desenvolver muitas técnicas e dispositivos apoiados em processamento digital de sinais e há um grande interesse pelo desenvolvimento de interfaces mais naturais, como sinais biológicos para o controle de próteses e dispositivos. Este trabalho tem por objetivo apresentar o desenvolvimento de um método de Inteligência Computacional baseado em Regressão Logística capaz de classificar 17 movimentos do segmento mão-braço realizados pelos voluntários do estudo através do processamento do sinal mioelétrico (SME) adquiridos dos sujeitos em questão. Adicionalmente é realizada uma avaliação da influência de alguns dos canais, características do sinal e movimentos executados na taxa de acerto global. Para a realização do sistema foi utilizado um aparato experimental capaz de adquirir os SME através de 12 canais utilizando eletrodos não invasivos e posteriormente digitalizá-los. Logo após efetua-se a extração das três características utilizadas no trabalho, que servem de entrada para o método de Regressão Logística. Para este estudo foram processados três bancos de dados que perfazem um total de 50 voluntários. A taxa média de acerto alcançada foi de 70,1%, considerando todas as variações de testes realizados enquanto a média para os melhores casos de cada variação de entrada realizada foi de 92,5%.
Through the devices and techniques developed in the field of Biomedical Instrumentation commonly is possible to offer treatment or solutions to provide a more pleasurable experience in society for people who have a disability or illness. With increasing computing capability in recent years, it has been possible to develop many techniques and devices supported by digital signal processing, and there is a great interest in the development of more natural interfaces, such as biological signals for the control of devices and prostheses. This work aims to present the development of a computational intelligence method based on Logistic Regression able to classify 17 movements of the hand-arm segment performed by the subjects of this study through the processing of the myoelectric signal (SME) acquired from the subject in question. Additionally, an assessment of the influence of some of the combination of the channels, signal characteristics and movements performed in the overall hit rate is additionally performed. To conduct the system has built an experimental apparatus able to acquire the SME through 12 channels using non-invasive electrodes and scan them. Thereafter there is a three features extraction from the signal which serves as input to the Logistic Regression method. For this study were processed three databases that compose 50 volunteers. The average hit rate achieved was 70.1%, considering all tests variations while the average for the best cases for each input variation performed was 92,5 %.

The thesis explores a possible sustainable future of mobility and the transition pathwayto it, focusing on the socio-cultural dimensions that shape and drive the way mobilityis understood. Goal-driven, transition-oriented policy recommendations are providedas the main result, derived from a combined backcasting and forecasting methodologyframework. The successful combination of backcasting and Causal Loop Diagrams isachieved by homogenising the outcomes of each assessment through the logic of theMulti-Level Perspective of transitions theory. The research highlights that reinforcing feedback mechanisms and a deeply embeddedculture of automobility are behind the enormous inertia and resilience of the currentmobility system. If a transition to a sustainable mobility future is to happen, the insightsgained from this study point to a necessary shift in cultural trends. The discourses ofunrestricted individual freedom, private property and materialistic cultures that legitimiseautomobility must be challenged. The thesis proves that the Multi-Level Perspective on transitions provides with a narrativecapable of integrating results from inherently different approaches to future studies. Themethodological framework developed in the study is generalisable and useful for situationswhere a normative goal in the distant future is pursued, while accounting for the reasonsbehind policy resistance in the current system configuration.

In recent years the amount of newly registered electric vehicles, hybrid electric vehicles, and plug-in hybrid electric vehicles has increased rapidly in the Swedish market. These vehicles could be classified as battery-powered electric vehicles, and a majority carry a lithium-ion battery. The demand for lithium is expected to increase considerably, as a result of such a swift growth in battery-powered electric vehicles. Thus, if the recycling rate of lithium stays at a low level, demand could reach a scarcity-level by 2050. While neither any infrastructure nor an established process for recycling lithium-ion batteries currently exists in Sweden, this study aims to provide necessary input and verified tools for the design of a future reverse supply chain for discarded lithium-ion batteries in Sweden. The literature review of this study covers the subjects of reverse logistics, supply chain network design, and operations research. A thorough situation analysis of the Swedish market for battery-powered electric vehicles is conducted, and the composition, function, and characteristics of lithium-ion batteries are studied. The study finds that estimations of future demand of recyclable lithium-ion batteries in Sweden could be between 206 711 and 726 974 tons accumulated, based on actual and predicted sales numbers until 2030. Even if it is obvious that there are going to be large quantities of such batteries requiring recycling in the future, and even if some established processes exist, there is no defined supply chain for the collection of those batteries. Finally, a mixed-integer programming model for the design and development of a future reverse supply chain is presented. The model, characterized as a discrete multi-period facility location/allocation model, can with minor modifications be used for problems with fluctuating demand or when the demand is assumed to slowly progress until it has reached a steady state.

Environmental issues have been highly in focus for several years. With the development of EMS, many companies get environmental improvements through implementing EMS. Also, "green logistics" turns out to be a popular issue. But the combination of environment issues and logistics system is rarely found in the previous researches. Therefore, environment-oriented logistics system design becomes the topic described here.

The purpose of the thesis is to see potential of integrating environment issues into logistic system by literature review and case study. With the help of our supervisors, two Swedish companies Sandvik SMT and FLB Logistik become case companies in the thesis. The analysis is based on literature review about logistics and environment, the information from both companies‟ websites as well as face-to-face interviews.

In analysis part, how logistics systems and environmental issues interact with each other is illustrated firstly. A proposed model based on logistics system decision-making model is shown. SWOT analysis is used to explain the outcomes and challenges of implementing EMS in Sandvik SMT. At last, the conditions such as customer environmental requirement and the cost for using EMS are briefly described.

Based on the research, further study should begin with the collection of quantitative data about environmental performance from manufacturing companies, suppliers, as well as retailers. More recommendations are given in the conclusion part.

När tillfälliga vägar skall anläggas sker vanligtvis ingen dimensionering i förväg, i de flesta fall dimensioneras och byggs de utifrån erfarenhet. Om en tillfällig väg skall användas som permanent väg efter det att byggnationen är färdigställd, kan det i enstaka fall ske en dimensionering på vägen. Exempel på detta är vid byggnation av vindkraftverk och skogsvägar. Företaget Auctoritas Projektstyrning AB har fått i uppdrag att upphandla samt projektleda nödvändigt fastighetsunderhåll för fastigheten Terränglöparen 9 beläget i Hallonbergen, Sundbybergs kommun. För att genomföra ROT-projektet utreds möjligheten för en tillfällig väg för att underlätta logistiken under produktionstiden. Syftet med arbetet är att utreda tekniska lösningar för uppbyggnad av överbyggnader till en tillfällig väg. Utredningen skulle resultera i ett förslag på lämpliga val med hänsyn tagen till kostnad och regeluppfyllnad. Detta applicerades sedan som en fallstudie med en tillfällig väg till Terränglöparen 9. Författarna har undersökt 10 olika väguppbyggnader med hänsyn till rådande markförhållanden, årsperiod, årsdygnstrafik per körfält samt kostnad. Utöver detta har föreslagen vägsträckning utretts med hänsyn till rådande topografi, fordonens svängradier och bärighetsklass. Detta ledde sedan till ett val av väguppbyggnad samt vägsträckning för en tillfällig väg till Terränglöparen 9.
When temporary roads are being constructed there is normally no design made in advance, in most cases they are built and dimensioned from experience. If a temporary road will be used as a permanent road after the construction is finished, there will occasionally be a complete design of the road. Example of this is when roads are built for wind power stations or forest roads. The company Auctoritas Projektstyrning AB has been assigned to project lead any necessary property maintenance for Terränglöparen 9 situated in Hallonbergen, Sundbybergs county. To go through with the renovations, the company is investigating the possibilities for a temporary road to ease the logistics during the production time. The purpose with this report is to investigate technical solutions for the construction of a temporary road. The investigation should result in a suggestion for appropriate choices with regard to cost and rules. This is later applied like a case study with a temporary road to Terränglöparen 9. The authors have explored ten different road constructions with regards to current land ratio, service years, annual traffic per lane and cost. In addition to this, a proposed road section has been investigated with regards to current topography, turning radius of lorries and load-bearing capacity. This led to a choice of road construction and a road section for a temporary road to Terränglöparen 9.

This thesis makes significant contributions to improving the use of Airport Safety Areas (ASAs) as aviation accident risk mitigation measures by developing improved accident frequency models and risk assessment methodologies. In recent years, the adequacy of ASAs such as the Runway End Safety Area and Runway Safety Area has come under increasing scrutiny. The current research found flaws in the existing ASA regulations and airport risk assessment techniques that lead to the provision of inconsistent safety margins at airports and runways. The research was based on a comprehensive database of ASA-related accidents, which was matched by a representative sample of normal operations data, such that the exposure to a range of operational and meteorological risk factors between accident and normal flights could be compared. On this basis, the criticality of individual risk factors was quantified and accident frequency models were developed using logistic regression. These models have considerably better predictive power compared to models used by previous airport risk assessments. An improved risk assessment technique was developed coupling the accident frequency models with accident location data, yielding distributions that describe the frequency of accidents that reach specific distances beyond the runway end or centreline given the risk exposure profile of the particular runway. The application of the proposed methodology was demonstrated in two case studies. Specific recommendations on ASA dimensions were made for achieving consistent levels of safety on each side of the runway. Advances made in this study have implications on the overall assessment and management of risks at airports.

Outsourcing breaks up the supply chain and often increases in number of stakeholders and organizations and therefore puts a higher demand on a well-functioning coordination of the material supply. The logistical task spectrum is characterized by a great degree of variety and dissimilarity which is due to the logistical role itself, functions within both overall economic and business processes, in value-added steps from the processing of raw material to the end user. Research in the field of global sourcing environment has been conducted in prior research, however, the outsourcing environments differs one from another. The purpose of this study is to identify critical logistical factors when transferring to a third party stakeholder. The findings are based on an extensive literature study in the field of logistics and a single case study. An interactive investigation at a large, multinational company provided opportunities to observe and participate in an ongoing global transfer and verify the applicability of the result (matrix concept). The observations were done over a three months’ period and gave the author the opportunity to investigate the logistical setup for the ongoing transfer. The company henceforth Genopower AB, is transferring the assembly and testing to a third party stakeholder located in Indonesia. The motives for the transfer is to increase the company’s market shares in Indonesia and further into Asia. The third party stakeholder, henceforth PT PAK does not have any prior experience in the Gas turbine (Power generation) industry. The study provides a generalized matrix with critical logistical factors which affects the logistical performance measurements, logistical cost and customer service elements. By presenting the findings in terms of factors, the matrix can be applicable on future outsourcing projects and give a clear insight in which of the factors is worth investigating further; prior, during or after the actual transfer as an evaluation tool.

Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2006.
Includes bibliographical references (leaves 102-103).
According to U.S. government surveys, 12% of Americans used taxi service in the previous month' and spent about $3.7 billion a year for cab fare.2 Taxi service is one of the major modes of public transportation. Despite providing services 24 hours a day, driving relentlessly with an empty taxicab in search of passengers and answering dispatch calls instantaneously, taxi service is ranked the most unsatisfactory mode of transportation by the public. Charging higher fares than other major modes of transportation and averaging 10 to 12 hours work day, taxi drivers have a difficult time to earn a sustainable income.Approximately half of all the taxi mileage is paid mileage; this means a significant portion of a taxi's time and fuel is spent on non-revenue generating activities, i.e. without passengers. Current taxi allocation is inefficient. The number of taxis and the geographical service areas which they serve are heavily regulated in most cities. With limited competition and strict regulations, taxi service suffers with customers having to endure long wait times and inferior services. The current taxi systems in most U.S. cities may be greatly improved from their current state.
(cont.) This thesis investigates the factors of inefficiency in the current taxi system, reviews previous taxi efficiency studies, and suggests possible solutions. After extensive literature reviews and field research, a computer simulation model has been built in the MATLAB environment. This computer model tests various attributes that affect logistic optimizations for taxi services. In particular, the effect of taxi fleet size, the quantity of hotspots, and the concentrations of customers at hotspots are analyzed in detail using the model. The metric of interest includes the customers' wait time, taxi revenue, and costs of operations. Results from the computer simulation experiments, field research, and literature review are analyzed and synthesized. Possible solutions are proposed as part of this thesis.
by Sonny Li.
S.M.

Manufacturing supply chains are invariably dynamic and complicated in nature. Hence, steady state models are not sufficient for analyzing and designing supply chains. Models of supply chains must accurately capture their dynamic behavior, which is determined by the structure of the organization, and the policies adopted by management. System dynamics modeling provides a powerful framework for this purpose. The use of system dynamics models in supply chain management has thus far been limited to explaining phenomenon like the bullwhip effect, and for policy development. We provide a structured approach for policy design, which doesnâ t rely on any simulation experiments. Further, we study the impact that information network design has on the response of supply chains. We use a combinatorial approach to develop guidelines for information network design. Further, we examine the possibility of utilizing a PID information feedback structure to enhance the responsiveness of the supply chain. Lastly, we propose a combined feedback feed-forward information structure to enable a supply chain to rapidly respond to disturbances whose effects are known. The goal of this dissertation is to provide a structured approach for the design of information network structure, and operating policy.
Ph. D.

Kompetenzzellenbasierte (regionale) Netze stellen besondere Anforderungen an die Modellierung, Planung und Gestaltung der Logistikstrukturen. Für die Logistikstrukturmodellierung werden ein generischer Beschreibungsrahmen für produktionslogistische soziotechnische Systeme, Definitionen u.a. zum zentralen Begriff Logistikstruktur sowie ein 3-Ebenen-Modell und Strukturtypen für eine vertiefende Materialflussanalyse und -synthese bereitgestellt. Für die Logistikstrukturplanung wird darauf aufbauend mit der Methode der Integrativen Prozess- und Systemstrukturierung (IPSS) eine Methode zur Behandlung von Strukturierungsproblemen konzipiert, die sowohl speziell für kompetenzzellenbasierte Netze als auch allgemein für Produktions- und Logistiksysteme angewandt werden kann. Für die Logistikstrukturgestaltung werden unter Modell- und Methodenverwendung Szenarien sowie Gestaltungs- und Vorzugslösungen für den Materialfluss abgeleitet
Competence-cell based (regional) networks put special requirements on the modelling, planning and design of logistics structures. For the modelling of logistics structures, a generic description framework for production logistic sociotechnical systems, definitions for, amongst others, the central term logistics structure as well as a 3-layer-model and structure types for a more detailed material flow analysis and synthesis are provided. For the planning of logistics structures, the Method of Integrative Process and System Structuring (IPSS) is developed as a method for handling structuring problems. It can be applied especially to Competence-cell based networks as well as generally to production and logistics systems. For the design of logistics structures, scenarios as well as design and preference solutions for the material flow are derived

In drug-testing experiments the primary responses of interest are efficacy and toxicity. These can be modeled as a bivariate quantal response using the Gumbel model for bivariate logistic regression. D-optimal and Q-optimal experimental designs are developed for this model The Q-optimal design minimizes the average asymptotic prediction variance of p(l,O;d), the probability of efficacy without toxicity at dose d, over a desired range of doses. In addition, a new optimality criterion, T -optimality, is developed which minimizes the asymptotic variance of the estimate of the therapeutic index. Most experimenters will be less familiar with the Gumbel bivariate logistic regression model than with the univariate logistic regression models which comprise its marginals. Therefore, the optimal designs based on the Gumbel model are evaluated based on univariate logistic regression D-efficiencies; conversely, designs derived from the univariate logistic regression model are evaluated with respect to the Gumbel optimality criteria. Further practical considerations motivate an exploration of designs providing a maximum compromise between the three Gumbel-based criteria D, Q and T. Finally, 5-point designs which can be generated by fitted equations are proposed as a practical option for experimental use.
Ph. D.

Contemporary co-living, as an accommodation alternative, is in a unique position to provide social fulfilment and sustainable development through sharing and community generation. However, it is increasingly clear that there is a lack of understanding of the realities of these spaces, and that this limiting the commercial application of the co-living model. Existing architecture, artefacts, and services are failing to accommodate the needs and objectives of collective users. Therefore, to experience the full ecological, social, and economic benefits of co-living, research must be performed to understand how residents share, experience, and inhabit space. This project responds by applying design thinking and collaborative exploration methods to produce case studies for two contrasting co-living developments in London, UK. Workshops, observations, literature research, and interviews build a foundation of contemporary knowledge. This inspires the design of an exploratory, pedagogical tool, in the form of a modular furniture collection. On top of its physical functionality, it offers developers the opportunity to learn and experiment towards a better understanding of how residents utilise space and resources. A prototype is built and tested with both case study sites acting as Living Labs. The design intervention produces a positive increase in resident well-being and confidence in interacting with the space around them. Moreover, developers confirm an increased understanding of the resident's needs and actions. The success of the project shows the role design can play in contemporary research, positive change, and sustainable development. The results have implications for co-living providers, researchers, and designers supporting sustainable lifestyle alternatives.

In the report we have investigated four high-rise buildings with the intentions to find out witch parts are prefabricated and what relation can be found between structural design, prefabrication and the logistics.

After the investigation we noticed that the grad of prefabrication in each one of the projects is good in relation to what purpose the building have and the given background. During the report we found that layout – structural design – prefabrication – logistics is an order that we think can make the production of the building more effective if followed. We believe that the prefabrication of high-rise buildings have potential to grow and get more optimized in the future.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.
Includes bibliographical references (leaves 177-186).
Service network design is critical to the profitability of express shipment carriers. In this thesis, we consider two challenging problems associated with designing networks for express shipment service. The first problem is to design an integrated network for premium and deferred services simultaneously. Related existing models adapted to this problem are intractable for realistic instances of this problem: computer memory requirements and solution times are excessive. We introduce a disaggregate information-enhanced column generation approach for this problem that reduces the number of variables to be considered in the integer program from hundreds of thousands to only thousands, allowing us to solve previously unsolvable problem instances. The second problem is to determine the express package service network design in its entirety, including aircraft routings, fleet assignments, and package flow routings, including hub assignments. Existing models applied to this problem have weak associated linear programming bounds and hence, fail to produce quality feasible solutions. For example, for a small network design problem instance it takes days to produce a feasible solution that is provably near- optimal using the best performing existing model. To overcome these tractability challenges, we introduce a new model, referred to as the gateway cover and flow formulation. Applying our new formulation to the same network design instance, it takes only minutes to find an optimal solution.
(cont.) Applying our disaggregate information-enhanced column generation approach and gateway cover and flow formulation and solution approach to the network design problems of a large express package service provider, we demonstrate tens of millions of dollars in potential annual operating cost savings and reductions in the numbers of aircraft needed to perform the service. Moreover, we illustrate that, though designed for tactical planning, our new model and solution approach can provide insights for strategic decision-making, such as hub opening/closure, hub capacity expansion, and fleet composition and size.
by Su Shen.
Ph.D.