Dissertations / Theses: 'Parameter list'

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Ortiz, Joseph Christian, and Joseph Christian Ortiz. "Estimation of Kinetic Parameters From List-Mode Data Using an Indirect Approach." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621785.

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This dissertation explores the possibility of using an imaging approach to model classical pharmacokinetic (PK) problems. The kinetic parameters which describe the uptake rates of a drug within a biological system, are parameters of interest. Knowledge of the drug uptake in a system is useful in expediting the drug development process, as well as providing a dosage regimen for patients. Traditionally, the uptake rate of a drug in a system is obtained via sampling the concentration of the drug in a central compartment, usually the blood, and fitting the data to a curve. In a system consisting of multiple compartments, the number of kinetic parameters is proportional to the number of compartments, and in classical PK experiments, the number of identifiable parameters is less than the total number of parameters. Using an imaging approach to model classical PK problems, the support region of each compartment within the system will be exactly known, and all the kinetic parameters are uniquely identifiable. To solve for the kinetic parameters, an indirect approach, which is a two part process, was used. First the compartmental activity was obtained from data, and next the kinetic parameters were estimated. The novel aspect of the research is using listmode data to obtain the activity curves from a system as opposed to a traditional binned approach. Using techniques from information theoretic learning, particularly kernel density estimation, a non-parametric probability density function for the voltage outputs on each photo-multiplier tube, for each event, was generated on the fly, which was used in a least squares optimization routine to estimate the compartmental activity. The estimability of the activity curves for varying noise levels as well as time sample densities were explored. Once an estimate for the activity was obtained, the kinetic parameters were obtained using multiple cost functions, and the compared to each other using the mean squared error as the figure of merit.

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Penna, Sérgio D., and Antônio Magno L. Espeschit. "A RELATIONAL APPROACH FOR MANAGING LARGE FLIGHT TEST PARAMETER LISTS." International Foundation for Telemetering, 2005. http://hdl.handle.net/10150/604785.

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ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada
The number of aircraft parameters used in flight-testing has constantly increased over the years and there is no sign that situation will change in the near future. On the contrary, in modern, software-driven, digital avionic systems, all sorts of parameters circulate through digital buses and can be transferred to on-board data acquisition systems more easily than those converted from traditional analog transducers, facilitating the request for more and more parameters to be acquired, processed, visualized, stored and retrieved at any given time. The constant unbalance between what parameter quantity engineers believe to be “sufficient” for developing and troubleshooting systems in a new aircraft, which tends to grow with aircraft complexity, and the associated cost of instrumenting a test prototype accordingly, which tends to grow beyond budget limits, pushes for new creative ways of handling both tendencies without compromising the ease of performing an engineering analysis directly from flight test data. This paper presents an alternative for handling large collections of flight test parameters through a relational approach, particularly in two important scenarios: the very basic creation and administration of the traditional “Flight Test Parameter List” and the transmission of selected data over a telemetry link for visualization in a Ground Station.

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3

Ekman, Petter. "A Sensitivity Study of Some Numerical and Geometrical Parameters Affecting Lift." Thesis, Linköpings universitet, Mekanisk värmeteori och strömningslära, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-124197.

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Volvo Car Corporation (VCC) uses Computational Fluid Dynamics (CFD) and wind tunnel during the aerodynamic development of new vehicles. In the past VCC main focus has been on the drag force correlation to the wind tunnel measurements but in recent years improved methods for lift force correlations has been highly wanted. Three objectives were considered in this study to improve the lift force correlation between the CFD simulations and wind tunnel measurements for geometrical configurations of the V60 and S60 models.Poor mesh resolution for the wall bounded flow existed for the VCC mesh method and therefore prisms layers were considered in this thesis to increase the mesh resolution inside the boundary layer.As slick tyres generally were used in the CFD simulations better geometrical correlation was wanted to be studied as it could improve the lift force correlation between CFD simulations and wind tunnel measurements. Therefore detailed tyres were considered in this study.As the coarsest surface mesh size was used for the underbody and the components inside the engine bay, where some of the highest flow velocities occurred, mesh refinements were investigated for engine bay and underbody in this study.The prisms layers improved the predicted behavior for the boundary layer as it captured the large velocity gradients more accurately. Due to this, the skin friction prediction was also improved. Different flow behavior around the front wheels and rear wake occurred due to earlier separation. The different flow field caused an improved correlation for the lift force but worsened correlation for the drag force due to increased pressure at the rear of the cars. However, the front lift force trend correlation for the considered configurations was improved with the prisms layer mesh method.The detailed tyres caused slight more disturbances for the underbody flow which caused more attached flow around the rear of the car hence lowered pressure. Earlier separation around the front wheels also occurred for the detailed tyre geometry as the disturbed flow around the wheels was increased. Slight improved correlation for the front and rear lift forces to the wind tunnel measurements could be seen with the detailed tyre compared to the slick tyre.The mesh refinements for the engine bay and underbody showed significant differences for the flow at the underbody which had significant impact on the flow at the rear wake for the V60 model. Minor differences could be seen for the aerodynamic forces for the baseline configuration for the V60 model while great differences occurred for the configurations affecting the underbody. Due to this significant improved correlation for the front and rear lift force trends were achieved for the underbody configurations with the refined engine bay and underbody mesh method.Conclusions could be drawn that the prisms layer caused earlier separation due to its increased mesh resolution for the wall bounded flow. However, finer mesh resolution was needed inside the boundary layer to ensure consistent separation behavior for both the considered models. Improved correlation for the front lift force could however be seen. The detailed tyre only had minor effects on the flow field and aerodynamic forces and therefore not so important to include for further studies. The refined engine bay and underbody caused significant improved lift force trend correlation to the wind tunnel measurements and should be considered for future studies. To improve the correlation between CFD simulations and wind tunnel measurements increased mesh resolution for the wall bounded flow should be considered to better capture the large velocity gradients close to the wall.

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Husman, S. H., J. C. Silvertooth, and C. Ramsey. "The Effects of PIX Application Timing on Lint Yield and Growth and Development Parameters." College of Agriculture, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/208614.

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Two field studies were conducted in 1991 to further evaluate Upland cotton yield and development responses to PIX application timing as a function cotton growth stage. Treatments imposed in 1991 were intended to further clarify some response trends observed in previous field studies. Treatments in 1991 were all at the maximum label rate of 1.5 pt./acre with application timing the main variable. Timing was based on growth stage and heat unit accumulation since date of planting. The study in Waddell, Az. resulted in no significant yield differences across all treatments. In contrast, the study at the Maricopa Agricultural Center resulted in a statistically significant yield response by approximately 100 lbs. lint /acre for all FIX treatments compared to the untreated check plots. Plant growth and development measurements indicated the height: node ratio counts to be a good reflection of vegetative tendencies under field conditions in the two studies.

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Li, Daxin. "Multi-objective design optimization for high-lift aircraft configurations supported by surrogate modeling." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8468.

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Nowadays, the competition among airlines seriously depend upon the saving operating costs, with the premise that not to degrade its services quality. Especially in the face of increasingly scarce oil resources, reducing fleets operational fuel consumption, is an important means to improve profits. Aircraft fuel economy is determined by operational management strategies and application technologies. The application of technologies mainly refers to airplane’s engine performance, Weight efficiency and aerodynamic characteristics. A market competitive aircraft should thoroughly consider to all of these aspects. Transport aircraft aerodynamic performance mainly is determined by wing’s properties. Wings that are optimized for efficient flight in cruise conditions need to be fitted with powerful high-lift devices to meet lift requirements for safe takeoff and landing. These high-lift devices have a significant impact on the total airplane performance. The aerodynamic characteristics of the wing airfoil will have a direct impact on the aerodynamic characteristics of the wing, and the wing’s effective cruise hand high-lift configuration design has a significant impact on the performance of transport aircraft. Therefore, optimizing the design is a necessary airfoil design process. Nowadays engineering analysis relies heavily on computer-based solution algorithms to investigate the performance of an engineering system. Computational fluid dynamics (CFD) is one of the computer-based solution methods which are more widely employed in aerospace engineering. The computational power and time required to carry out the analysis increases as the fidelity of the analysis increases. Aerodynamic shape optimization has become a vital part of aircraft design in the recent years. Since the aerodynamic shape optimization (ASO) process with CFD solution algorithms requires a huge amount of computational power, there is always some reluctance among the aircraft researchers in employing the ASO approach at the initial stages of the aircraft design. In order to alleviate this problem, statistical approximation models are constructed for actual CFD algorithms. The fidelity of these approximation models are merely based on the fidelity of data used to construct these models. Hence it becomes indispensable to spend more computational power in order to convene more data which are further used for constructing the approximation models. The goal of this thesis is to present a design approach for assumed wing airfoils; it includes the design process, multi-objective design optimization based on surrogate modelling. The optimization design stared from a transonic single-element single-objective optimization design, and then high-lift configurations were two low-speed conditions of multi-objective optimization design, on this basis, further completed a variable camber airfoil at low speed to high-lift configuration to improve aerodynamic performance. Through this study, prove a surrogate based model could be used in the wing airfoil optimization design.

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Boberg, Frida. "Simulation of dynamic and static behavior of an electrically powered lift gate." Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11627.

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Continental Automotive Systems is a German company that develops control systems for different applications in cars. A control system for electrically powered lift gates that are opened or closed on the driver’s command is one of the products developed. The drive system itself is composed of a spindle that is driven by a DC-motor over a gear and a spring. When developing the control system it is convenient to use a simulation model instead of having to implement it on the system every time. The simulation analytically describes how the system is behaving.

In this thesis a simulation model of a drive system and a lift gate is developed and evaluated. The model parameters are estimated using System Identification Toolbox in Matlab.

Continental Automotive Systems är ett tyskt företag som utvecklar styrsystem för olika tillämpningar i bilar. Bland annat utvecklas ett styrsystem till eldrivna bakluckor som öppnas och stängs av föraren per knapptryck. Själva drivanordningen består av en skruv som drivs av en likströmsmotor över en utväxling och en fjäder. Då man vill utveckla styrsystemet utan att behöva implementera det på systemet varje gång är en simuleringsmodell av drivanordningen och luckan ett bra hjälpmedel. Denna simuleringsmodell kan då analytiskt beräkna hur systemet uppför sig.

I detta examensarbete har en simuleringsmodell av en drivanordning med tillhörande lucka utvecklats och utvärderats. Modellparametrarna estimerades med hjälp av System Identification Toolbox i Matlab.

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7

Siekmann, Lisa [Verfasser]. "Die Fleischbeschaffenheit der Zweinutzungshuhnlinie Lohmann Dual. Eine vergleichende Betrachtung (bio-)chemischer, physikalischer, struktureller und sensorischer Parameter / Lisa Siekmann." Hannover : Stiftung Tierärztliche Hochschule Hannover, 2019. http://d-nb.info/1189654628/34.

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Husman, S. H., J. C. Silvertooth, and C. Ramsey. "The Effects of PIX Application Timing on Upland Cotton Lint Yield and Growth and Development Parameters." College of Agriculture, University of Arizona (Tucson, AZ), 1993. http://hdl.handle.net/10150/209554.

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Four commercial scale field studies were conducted in 1991 and 1992 to further evaluate Upland cotton yield and development responses to PIX application timing as a function of cotton growth stage. Treatments imposed in both years intended to further clarify some response trends observed in previous years of field studies. Treatments were all at the maximum label rate of one and one half pints with application timing the main variable. Timing was based on heat unit accumulation and resultant growth stage since date of planting. Two of the four studies resulted in significant lint yield increase of roughly one hundred pounds across all PIX treatments in contrast to the untreated check. The two studies which resulted in lint yield increases both had height:node ratio measurements in excess (vegetative) of previously defined guidelines.

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Husman, S. H., and J. C. Silvertooth. "The Effects of PIX Application Timing on Upland Cotton Lint Yield and Growth and Development Parameters." College of Agriculture, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/209610.

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Six commercial scale field studies were conducted from 1991-1993 to further evaluate and predict Upland cotton yield and development responses to PIX application timing as a function of cotton growth and condition. Treatments imposed intended to further clarify some response trends observed in previous years of field studies. Treatments were all at the maximum label rate of one and one half pints with application timing the main variable. Timing was based on heat unit accumulation and resultant growth stage since date of planting. Two of the six studies resulted in significant lint yield increase of roughly one hundred pounds across all PIX treatments in contrast to the untreated check. The two studies which resulted in lint yield increases both had height: node ratio measurements in excess (vegetative) of previously defined guidelines.

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Barthelmäs, Lisa Marie [Verfasser]. "Abgrenzung von zentral und peripher vestibulärem Schwindel anhand von klinischen Parametern und Magnetresonanztomographie / Lisa Marie Barthelmäs." Ulm : Universität Ulm, 2019. http://d-nb.info/1190178192/34.

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Violeta, Knežević. "Uticaj parametara osmotske dehidratacije na kinetiku, funkcionalne i antioksidativne karakteristike lista koprive (Urtica dioica)." Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110257&source=NDLTD&language=en.

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U ovoj disertaciji proučavana je osmotskadehidratacija lista koprive u dva različitaosmotska rastvora: 1. vodenom rastvorusaharoze i natrijum hlorida i 2. melasi šećernerepe. Ispitivan je uticaj temperature procesa(20°C, 35°C i 50°C) i vremena imerzije (30, 60i 90 min) na gubitak vode, priraštaj suvematerije, sadržaj suve materije, vrednostiaktivnosti vode, mikrobiooške promene,promenu mineralnog sastava (Ca, Mg, Na, K,Fe, Cu, Zn, Mn, Co) i promenu antioksidativneaktivnosti, tokom osmotske dehidratacije lista koprive.Dokazano je da se povećanjem temperature iproduženjem vremena trajanja procesapospešuje prenos mase tj. migracija molekulavode iz tretiranog biljnog materijala u okolnirastvor, i prodiranje molekula rastvorenesupstance iz osmotskog rastvora u tretiranobiljno tkivo.Snižene aw vrednosti u svim ispitivanimuzorcima ukazuju na pozitivan uticaj osmotskedehidratacije na mikrobiološku stabilnosttretiranog lista koprive. Dobijeni rezultati supokazali značajno poboljšanje mineralnogsastava lista koprive, dehidriranih u melasišećerne repe, dok je kod uzoraka tretiranih urastvoru saharoze i natrijumhlorida uočenosmanjenje sadržaja ispitivanih mineralnihmaterija. Nasuprot rastvoru saharoze i natrijumhlorida koji je uticao na opadanje ukupneantioksidativnosti osmotski dehidriranihuzoraka, melasa šećerne repe, kao bogat izvorprirodnih antioksidanasa, doprinosi povećanjuantioksidativnosti i poboljšanju funkcionalnogkvaliteta dehidriranog produkta.Statističkom obradom rezultata, uočeno je dasu optimalni procesni parametri u pogleduefikasnosti procesa, kao i mikrobiološkog,nutritivnog i funkcionalnog kvaliteta osmotskidehidriranog lista koprive, vreme trajanjaprocesa od 60 min, na temperaturi od 50°C, umelasi šećerne repe kao osmotskom rastvoru.
The osmotic dehydration of the nettle leaf intotwo different osmotic media was studied in thisdissertation: 1. Aqueous solution of sucrose andsodium chloride and 2. Sugar beet molasses.The effects of the process temperature (20 °C,35 °C and 50 °C) and the immersion time (30,60 and 90 min) on water loss, solid gain, drymatter content, water activity, microbialchanges, mineral composition (Ca, Mg, Na, K,Fe, Cu, Zn, Mn, Co) and the change in the antioxidant activity during osmotic dehydrationof the nettle leaf were studied in thisinvestigation.It has been proved that the increase intemperature and the prolonging of process time,accelerate the mass transfer, i. e., the migrationof the water molecules from the treated plantmaterial to the surrounding osmotic solution,and also the penetration of the molecules fromthe osmotic solution into the treated plant tissue.The reduced aw values in all tested samplesindicate the positive effect of osmoticdehydration on the microbiological stability ofthe treated nettle leaf. The obtained resultsshowed a significant improvement in themineral composition of the nettle leafdehydrated in sugar beet molasses, while thedecrease in the mineral content was observed inthe samples treated with sucrose and sodiumchloride solution. Contrary to the sucrose andsodium chloride solution, which negativelyaffected the overall antioxidative effect ofosmotically dehydrated samples, sugar beetmolasses contributed to an increase inantioxidantity, being a rich source of naturalantioxidants, and it also improves the functionalquality of the dehydrated product.Statistical analysis of the obtained experimentalresults showed that optimal process parametersin terms of process efficiency, as well asmicrobiological, nutritive and functional qualityof the osmotically dehydrated leaf net, could bereached after 60 min of osmotic treatment, at atemperature of 50 °C, using sugar beet molassesas an osmotic solution.

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Hort, Zbyněk. "Parametry laserového paprsku." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318845.

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The diploma thesis consists of the three main parts. The first part deals with the theoretical description of the laser technology and other unconventional technologies. In the second part, the thesis is focused on testing the parameters of the laser and evaluating the most suitable parameters. In the last part the diploma thesis deals with comparison of unconventional technologies in terms of cut quality

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Gerstner, Lisa [Verfasser], Patrick [Akademischer Betreuer] Friederich, Marc [Gutachter] Martignoni, and Patrick [Gutachter] Friederich. "Vergleichende Evaluation makrohämodynamischer Parameter von perioperativen Algorithmen der zielgerichteten Therapie / Lisa Gerstner ; Gutachter: Marc Martignoni, Patrick Friederich ; Betreuer: Patrick Friederich." München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/1214368603/34.

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Santos, Vidiany Aparecida Queiroz [UNESP]. "Perfil microbiano, físico-químico e análise das boas práticas de fabricação (BPF) de queijos minas frescal e ricota." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/88372.

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Made available in DSpace on 2014-06-11T19:23:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-02Bitstream added on 2014-06-13T18:50:32Z : No. of bitstreams: 1 santos_vaq_me_sjrp.pdf: 586910 bytes, checksum: ec20d7bdb371005191d77053bb2d959e (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Alguns queijos frescos como o Minas frescal e a ricota, apresentam elevada atividade de água e diversidade nutricional, fatores que propiciam a proliferação e o desenvolvimento de microbiota oportunista, prejudicando a qualidade e a integridade destes produtos. Diversos microrganismos são propostos como bioindicadores de contaminação da matéria-prima e/ou do produto pronto para o consumo. Para evitar quaisquer fontes de contaminação é imprescindível a adoção de Boas Práticas de Fabricação (BPF), as quais podem ser avaliadas por meio da aplicação do formulário check-list. Nesse contexto, este estudo objetivou avaliar as condições higiênico-sanitárias e adequações quanto às BPF, em uma indústria de laticínios de pequeno porte, produtora de queijos Minas frescal e ricota, localizada em São José do Rio Preto – SP, por meio do monitoramento microbiológico, físico-químico, e aplicação de check-list. Foram realizadas análises, conforme o fluxograma de fabricação, nas seguintes etapas: água, leite pasteurizado, coalho, massa, soro, superfície palmar dos manipuladores e tanque de coagulação, e queijos Minas frescal e ricota logo após o processamento (t0) e com cinco dias de vida de prateleira (t5). Tais etapas foram monitoradas quanto à qualidade microbiológica, por meio da determinação do Número Mais Provável (NMP) de coliformes totais e termotolerantes; contagem de Staphylococcus coagulase positiva e bactérias aeróbias mesófilas; pesquisa de Escherichia coli, Salmonella spp. e Listeria monocytogenes. A contagem de bactérias aeróbias mesófilas foi efetuada apenas nas amostras de água. As análises de determinação do NMP de coliformes totais, termotolerantes foram realizadas para todas as amostras. A contagem de Staphylococcus aureus, pesquisa de Escherichia coli e de Salmonella spp., foram efetuadas para todas as amostras citadas...
Some fresh cheeses as Minas frescal and ricota present high water activity and nutritional diversity, factors that permit the proliferation and the development of opportunist microrganisms, damaging the quality and integrity of these products. Several microrganisms are proposed as bioindicators of raw material and/or product ready for consumption contamination. To avoid any contamination source it`s indispensable to adopt Good Manufacturing Practices (GMP), which may be evaluated by application of checklist form. According to the presented, this study had the objective of evaluate the hygienic sanitary conditions and adequacies, in relation to the GMP, at a small dairy industry; which produces ricota and Minas frescal cheeses, located in São José do Rio Preto - SP by the physical-chemical and microbiological monitoring and check-list application. The analyses were done according to the following production stages: water, pasteurized milk, curd, mass, sour, manipulator hands, coagulation tank, ricota and Minas frescal cheese right after the processing (t0) and with five days of shelf-life (t5). Such stages were monitored in relation to the microbiological quality by the determination of the Most Probable Number (MPN) of total and thermotolerant coliforms; mesophilic aerobic bacteria and Staphylococcus aureus counting; research of Escherichia coli, Salmonella spp. and Listeria monocytogenes. The counting of mesophilic aerobic bacteria was done only in the water samples. The analyses of the determination of the MPN of total and thermotolerant coliforms were done for all samples. The counting of Staphylococcus aureus, Escherichia coli and Salmonella spp. research were done for all samples except water. The analysis of Listeria monocytogenes was done only for Minas frescal and ricotta cheeses. For the water analysis it was verified that 3 samples (25%) presented... (Complete abstract click electronic access below)

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Wilfing, Lisa Steffi Franziska [Verfasser], Kurosch [Akademischer Betreuer] [Gutachter] Thuro, Robert [Gutachter] Galler, and Ewald [Gutachter] Tentschert. "The Influence of Geotechnical Parameters on Penetration Prediction in TBM Tunneling in Hard Rock : Special focus on the parameter of rock toughness and discontinuity pattern in rock mass / Lisa Steffi Franziska Wilfing. Betreuer: Kurosch Thuro. Gutachter: Robert Galler ; Ewald Tentschert ; Kurosch Thuro." München : Universitätsbibliothek der TU München, 2016. http://d-nb.info/1105646742/34.

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Heim, da costa Réjane. "Etude du controle du biofilm developpe dans un lit fluidise triphasique en epuration carbonee aerobie." Toulouse, INSA, 1989. http://www.theses.fr/1989ISAT0011.

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Cette recherche fait l'objet d'une etude fondamentale du controle du biofilm dans un lit fluidise triphasique en epuration carbonee aerobie. Differents parametres de controle ont ete etudies: parametres physiques (attrition et cisaillement) et parametres biologiques (charge surfacique). La methodologie experimentale mise au point permet la caracterisation du lit de bioparticules et du developpement du biofilm

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Santos, Vidiany Aparecida Queiroz. "Perfil microbiano, físico-químico e análise das boas práticas de fabricação (BPF) de queijos minas frescal e ricota /." São José do Rio Preto : [s.n.], 2009. http://hdl.handle.net/11449/88372.

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Orientador: Fernando Leite Hoffmann
Banca: Crispin Humberto Garcia Cruz
Banca: Walkíria Hanada Viotto
Banca: Roberto da Silva
Resumo: Alguns queijos frescos como o Minas frescal e a ricota, apresentam elevada atividade de água e diversidade nutricional, fatores que propiciam a proliferação e o desenvolvimento de microbiota oportunista, prejudicando a qualidade e a integridade destes produtos. Diversos microrganismos são propostos como bioindicadores de contaminação da matéria-prima e/ou do produto pronto para o consumo. Para evitar quaisquer fontes de contaminação é imprescindível a adoção de Boas Práticas de Fabricação (BPF), as quais podem ser avaliadas por meio da aplicação do formulário check-list. Nesse contexto, este estudo objetivou avaliar as condições higiênico-sanitárias e adequações quanto às BPF, em uma indústria de laticínios de pequeno porte, produtora de queijos Minas frescal e ricota, localizada em São José do Rio Preto - SP, por meio do monitoramento microbiológico, físico-químico, e aplicação de check-list. Foram realizadas análises, conforme o fluxograma de fabricação, nas seguintes etapas: água, leite pasteurizado, coalho, massa, soro, superfície palmar dos manipuladores e tanque de coagulação, e queijos Minas frescal e ricota logo após o processamento (t0) e com cinco dias de vida de prateleira (t5). Tais etapas foram monitoradas quanto à qualidade microbiológica, por meio da determinação do Número Mais Provável (NMP) de coliformes totais e termotolerantes; contagem de Staphylococcus coagulase positiva e bactérias aeróbias mesófilas; pesquisa de Escherichia coli, Salmonella spp. e Listeria monocytogenes. A contagem de bactérias aeróbias mesófilas foi efetuada apenas nas amostras de água. As análises de determinação do NMP de coliformes totais, termotolerantes foram realizadas para todas as amostras. A contagem de Staphylococcus aureus, pesquisa de Escherichia coli e de Salmonella spp., foram efetuadas para todas as amostras citadas... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Some fresh cheeses as Minas frescal and ricota present high water activity and nutritional diversity, factors that permit the proliferation and the development of opportunist microrganisms, damaging the quality and integrity of these products. Several microrganisms are proposed as bioindicators of raw material and/or product ready for consumption contamination. To avoid any contamination source it's indispensable to adopt Good Manufacturing Practices (GMP), which may be evaluated by application of checklist form. According to the presented, this study had the objective of evaluate the hygienic sanitary conditions and adequacies, in relation to the GMP, at a small dairy industry; which produces ricota and Minas frescal cheeses, located in São José do Rio Preto - SP by the physical-chemical and microbiological monitoring and check-list application. The analyses were done according to the following production stages: water, pasteurized milk, curd, mass, sour, manipulator hands, coagulation tank, ricota and Minas frescal cheese right after the processing (t0) and with five days of shelf-life (t5). Such stages were monitored in relation to the microbiological quality by the determination of the Most Probable Number (MPN) of total and thermotolerant coliforms; mesophilic aerobic bacteria and Staphylococcus aureus counting; research of Escherichia coli, Salmonella spp. and Listeria monocytogenes. The counting of mesophilic aerobic bacteria was done only in the water samples. The analyses of the determination of the MPN of total and thermotolerant coliforms were done for all samples. The counting of Staphylococcus aureus, Escherichia coli and Salmonella spp. research were done for all samples except water. The analysis of Listeria monocytogenes was done only for Minas frescal and ricotta cheeses. For the water analysis it was verified that 3 samples (25%) presented... (Complete abstract click electronic access below)
Mestre

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Veith, Lisa Katharina [Verfasser], and Florian [Akademischer Betreuer] Beigel. "Assoziation des Vitamin D-Status mit Serum-Parametern des Eisenmangels bei Patienten mit chronisch entzündlichen Darmerkrankungen / Lisa Katharina Veith ; Betreuer: Florian Beigel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/1239049552/34.

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Bahr, Lisa-Marie [Verfasser], and Andreas [Akademischer Betreuer] Mühlberger. "Investigating the role of the central and the peripheral benzodiazepine receptor on stress and anxiety related parameters / Lisa-Marie Bahr ; Betreuer: Andreas Mühlberger." Regensburg : Universitätsbibliothek Regensburg, 2020. http://d-nb.info/1219301167/34.

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HOUMMADI, AZIZ. "Hydrogenolyse catalytique du sorbitol : mise au point d'un reacteur a lit fixe et optimisation des parametres de la reaction." Amiens, 1990. http://www.theses.fr/1990AMIES015.

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L'hydrogenolyse catalytique des polyols a ete etudiee depuis longtemps. La plupart de ces etudes ont porte sur des systemes fermes ou reacteurs a lit agite. Nous avons choisi de mener notre etude dans un systeme continu ou reacteur a lit fixe. Les catalyseurs les plus utilises sont des metaux ou des melanges de metaux du groupe viii. L'exploitation industrielle eventuelle de notre systeme nous a fait choisir le nickel sur kieselguhr comme catalyseur et le sorbitol comme produit de depart pour leur faible cout. Les produits reactionnels ont ete doses par h. P. L. C. Nous avons utilise une colonne echangeuse d'ion avec de l'eau acidulee comme eluant pour doser le glycerol, l'ethylene glycol et le 1,2 propanediol, qui sont les principaux produits formes, directement a la sortie du reacteur. Notre objectif etait de trouver les conditions optimales, dans notre reacteur, pour un rendement maximal en glycerol. Pour atteindre cet objectif nous avons utilise la methologie de la recherche experimentale qui permet de definir l'influence des differents parametres et leurs interactions respectives. Cela nous a permis de trouver les conditions pour un rendement de 40% en glycerol. Nous avons aussi fait quelques essais avec le ruthenium sur charbon qui nous a donne de meilleurs rendements en glycerol dans des conditions plus douces que dans le cas du nickel

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De, Grave Emiel. "Reverse Engineering of Passenger Jets - Classified Design Parameters." Master's thesis, Aircraft Design and Systems Group (AERO), Department of Automotive and Aeronautical Engineering, Hamburg University of Applied Sciences, 2017. http://d-nb.info/1204457298.

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This thesis explains how the classified design parameters of existing passenger jets can be determined. The classified design parameters are; the maximum lift coefficient for landing and take-off, the maximum aerodynamic efficiency and the specific fuel consumption. The entire concept is based on the preliminary sizing of jet powered civil aeroplanes. This preliminary sizing is explained in detail because it is the foundation of the final result. The preliminary sizing is combined using reverse engineering which is not a strict method. Therefore, only the basics are explained. By applying reverse engineering on the preliminary sizing and aiming for the classified design parameters as output, formulas are derived to calculate the maximum lift coefficients, the maximum aerodynamic efficiency and the specific fuel consumption. The goal is to calculate these parameters, using only aircraft specifications that are made public by the manufacturer. The calculations are complex with mutual relations, iterative processes and optimizations. Therefore, it is interesting to integrate everything in a tool. The tool is built in Microsoft Excel and explained in detail adding operating instructions. The program is executed for miscellaneous aeroplanes, supported with the necessary comments. Investigated aeroplanes are: Caravelle 10B (Sud-Aviation), Boeing 707-320C, BAe 146-200 (British Aerospance), A320-200 (Airbus), "The Rebel" (based on A320), Boeing SUGAR High, Boeing 747-400, Blended Wing Body VELA 2 (VELA) and Dassault Falcon 8X.

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Gulec, Mustafa Alpertunga. "Vector Controlled Elevator Drive." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607186/index.pdf.

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In this thesis, a practical vector controlled elevator drive is presented. Indirect vector control of induction machine is investigated in theory and then implemented. Control technique is compared with scalar control and induction machine is compared with dc motor. The operation of the system depends on induction machine parameters, so how to accurately and automatically obtaining of the parameters is also presented. Finally, the elevator system is introduced, the application of this control system to the elevator system is described and a basic elevator control system is simulated.

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Zejda, Vojtěch. "Návrh vybraných strojně technologických zařízení ČOV se zaměřením na zlepšení hydraulických účinností." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-433503.

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The wastewater treatment process is one of the most important processes which contributes to the protection of the environment. This process can also potentially recover necessary and scarce raw materials, such as phosphorus. Research of the wastewater treatment technology is an increasingly relevant topic and more innovative knowledge should be gradually implemented into existing plants. However, the implementation of such technology involves increased investment and often operating costs. This is, why there is a growing interest in improving the energy intensity and hydraulic efficiency of the installed wastewater plant machinery. The optimization of operating parameters in such machinery can also bring significant savings, which can be potentially re-invested into other technologies. This work deals with the issue of proper evaluation of installed machinery for the selection of operating parameters and assessment of their significance. As the challenge, wastewater treatment technology is very sensitive towards the combination of technological equipment and incorrect operational parameters can lead to erroneous evaluation of the efficiency of individual equipment or inappropriate engineering proposals. To eliminate these risks, an analytical procedure for the selection and evaluation of parameters is proposed in this work. This procedure is demonstrated on six types of equipment. To verify the conclusions of the proposed procedure, a model design of the equipment was performed, in which the influence of individual parameters was concisely assessed. By using the data, the proposed procedure could be validated more specifically. In this work, the necessary data for the design was obtained by experimental research and extensive testing. The results confirm the practical applicability of the proposed procedure.

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Sprenger, Lisa [Verfasser]. "Die Rolle der fluoreszenzoptischen Bildgebung Xiralite® im Therapiemonitoring bei Patienten mit früher, aktiver Rheumatoider Arthritis – im Vergleich zu klinischen Parametern und zum Gelenkultraschall / Lisa Sprenger." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2020. http://d-nb.info/1206181893/34.

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Sprenger, Lisa Ines [Verfasser]. "Die Rolle der fluoreszenzoptischen Bildgebung Xiralite® im Therapiemonitoring bei Patienten mit früher, aktiver Rheumatoider Arthritis – im Vergleich zu klinischen Parametern und zum Gelenkultraschall / Lisa Sprenger." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2020. http://d-nb.info/1206181893/34.

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Pantoja, Lilian Roriz Carvalho. "Par?metros urban?sticos para habita??o de interesse social: uma an?lise cr?tica para as Rocas em Natal/RN." Universidade Federal do Rio Grande do Norte, 2006. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18294.

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Through the comparative critical analysis of the demanded urbanistic parameters in the legislation and of the urbanistic index found in the Rocas neighbourhood, having as study object the already consolidated constructions of residential use, intended to demonstrate that the neighbourhood needes specific norms and that the limits established for recognition of Special Areas of Social Interest for the urbanistic legislation of the City of Natal would have to be reviewed and to be brought up to date, once they show occupations like the ones of the reffered neighbourhood. At a first moment, bibliographical revision and elaboration of the theoretical referencial had been made, , to analyze afterwards the urbanistic legislation for the neibourhood of Rocas, that determines relative parameters for the sizes of land lots, coefficients of exploitation, minimum taxes of occupation and retreat. Through a field research in the area, a study on the occupation description was done at first, characterization of the neibourhood through the study of the social-economic aspects, of the existing infrastructure in the place, environmental aspects, morphologic and tipolgic analysis of the neibourhood as a whole. From the grouping of the found characteristics, sub-zones had been delimited, where the real object of study was detached to be analyzed. From the Sub-zoning, a statistic sampling was carried through with the intention to examine which of the urbanistic index is found in the dwellings of that already materialized place. This sampling, of one hundred and eighteen residences, was carried through by measurement of the lots and existing constructions in these places. Through this survey, for each habitacional unit, area of the lot, constructed area, retreats and coefficient of exploitation had been calculated. The comparison between the legislation parameters and the index found in the place reveal an expressive index of urbanistic irregularity and the necessity of special regulation for the Rocas neibourhood due to its specific social-space characteristic
Atrav?s da an?lise cr?tica comparativa dos par?metros urban?sticos exigidos na legisla??o e dos ?ndices urban?sticos encontrados no bairro das Rocas, tendo como objeto de estudo as edifica??es j? consolidadas de uso residencial, pretendeu-se demonstrar que o bairro das Rocas precisa de normas espec?ficas e que os limites estabelecidos para reconhecimento de ?reas Especiais de Interesse Social pela legisla??o urban?stica do Munic?pio de Natal deveriam ser revistos e atualizados, uma vez que deixam ? margem ocupa??es como as do dito bairro. Num primeiro momento, foram feitas revis?o bibliogr?fica e elabora??o do referencial te?rico, para em seguida, analisar a legisla??o urban?stica para o bairro das Rocas, que determina par?metros relativos a tamanhos de lote, coeficientes de aproveitamento, taxas de ocupa??o e recuos m?nimos. Atrav?s da pesquisa de campo na ?rea, foi feito, primeiramente, um estudo sobre o hist?rico de ocupa??o, caracteriza??o do bairro atrav?s do estudo dos aspectos s?cio-econ?micos, da infra-estrutura existente no local, aspectos f?sico-ambientais, an?lise morfol?gica e tipol?gica do bairro como um todo. A partir do agrupamento das caracter?sticas encontradas, foram delimitadas sub-zonas, onde o objeto de estudo propriamente dito foi destacado para ser analisado. A partir do Sub-zoneamento, foi realizada uma amostragem estat?stica com o intuito de examinar quais os ?ndices urban?sticos s?o encontrados nas habita??es daquele local j? concretizado. Essa amostragem, de cento e dezoitos resid?ncias, foi realizada atrav?s de medi??o dos lotes e constru??es existentes nestes. Atrav?s deste levantamento, para cada unidade habitacional, foram calculados ?rea do lote, ?rea constru?da, recuos e coeficiente de aproveitamento. A compara??o entre os par?metros orientados na legisla??o e os ?ndices encontrados no local revela um ?ndice expressivo de irregularidade urban?stica e a necessidade de regulamenta??o especial para o bairro das Rocas devido sua espec?fica caracter?stica s?cio-espacial

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Chaves, Alexsandra Cristina. "S?ntese, estudo cin?tico e an?lise microestrutural do sistema c?rio-n?quel obtido pelo m?todo pechini." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12732.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The cerium oxide has a high potential for use in removing pollutants after combustion, removal of organic matter in waste water and the fuel-cell technology. The nickel oxide is an attractive material due to its excellent chemical stability and their optical properties, electrical and magnetic. In this work, CeO2-NiO- systems on molars reasons 1:1(I), 1:2(II) e 1:3(III) metal-citric acid were synthesized using the Pechini method. We used techniques of TG / DTG and ATD to monitor the degradation process of organic matter to the formation of the oxide. By thermogravimetric analysis and applying the dynamic method proposed by Coats-Redfern, it was possible to study the reactions of thermal decomposition in order to propose the possible mechanism by which the reaction takes place, as well as the determination of kinetic parameters as activation energy, Ea, pre-exponential factor and parameters of activation. It was observed that both variables exert a significant influence on the formation of complex polymeric precursor. The model that best fitted the experimental data in the dynamic mode was R3, which consists of nuclear growth, which formed the nuclei grow to a continuous reaction interface, it proposes a spherical symmetry (order 2 / 3). The values of enthalpy of activation of the system showed that the reaction in the state of transition is exothermic. The variables of composition, together with the variable temperature of calcination were studied by different techniques such as XRD, IV and SEM. Also a study was conducted microstructure by the Rietveld method, the calculation routine was developed to run the package program FullProf Suite, and analyzed by pseudo-Voigt function. It was found that the molar ratio of variable metal-citric acid in the system CeO2-NiO (I), (II), (III) has strong influence on the microstructural properties, size of crystallites and microstrain network, and can be used to control these properties
O ?xido de c?rio tem um alto potencial em uso para remo??o de p?s poluentes de combust?o, remo??o de mat?rias org?nicas de ?guas residuais e na tecnologia de c?lulas a combust?vel. O ?xido de n?quel ? um material atraente devido a sua excelente estabilidade qu?mica, bem como suas propriedades ?pticas, el?tricas e magn?ticas. Neste trabalho, sistemas de CeO2-NiO nas raz?es molares 1:1(I), 1:2(II) e 1:3(III) metal-?cido c?trico foram sintetizados utilizando o m?todo Pechini. Foram utilizadas t?cnicas de TG / DTG e DTA para monitorar o processo de degrada??o da mat?ria org?nica at? a forma??o do ?xido. Atrav?s da an?lise termogravim?trica e aplicando-se o m?todo din?mico proposto por Coats-Redfern, foi poss?vel realizar estudos das rea??es de decomposi??o t?rmica com o intuito de propor o poss?vel mecanismo pelo qual a rea??o se processa, como tamb?m, a determina??o de par?metros cin?ticos como energia de ativa??o, Ea, fator pr?-exponencial e par?metros termodin?micos de ativa??o. Foi observado que ambas as vari?veis exercem grande influ?ncia na forma??o do complexo polim?rico precursor. O modelo que melhor ajustou-se aos dados experimentais no modo din?mico foi o R3, que consiste de crescimento nuclear, onde, os n?cleos formados crescem at? atingirem uma interface de rea??o cont?nua, este, prop?e uma simetria esf?rica (ordem 2/3). Os valores de entalpia de ativa??o do sistema evidenciaram que a rea??o no estado de transi??o ? exot?rmica. As vari?veis de composi??o, juntamente com a vari?vel temperatura de calcina??o foram estudadas por diferentes t?cnicas, tais como: DRX, IV e MEV. Tamb?m foi realizado um estudo microestrutural pelo m?todo de Rietveld, cuja rotina de c?lculo foi desenvolvida para ser executada no pacote do programa Fullprof Su?te, e analisada pela fun??o pseudo-Voigt. Verificou-se que a vari?vel raz?o molar metal-?cido c?trico no sistema CeO2-NiO (I),(II),(III) tem forte influ?ncia nas propriedades microestruturais, tamanho de cristalito e microdeforma??o de rede, e podem ser usados para controlar estas propriedades

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Brucker, Lisa [Verfasser], and Jürgen [Akademischer Betreuer] Zentek. "Untersuchungen zur Eignung von Mangoschalen (Mangifera indica L.) in der Tierernährung und deren Einfluss auf die zootechnische Leistung sowie verdauungsphysiologische und mikrobiologische Parameter bei Absetzferkeln / Lisa Brucker ; Betreuer: Jürgen Zentek." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2016. http://d-nb.info/1113686847/34.

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Berberich, Anna Lisa [Verfasser], Martin [Akademischer Betreuer] Halle, Johannes [Akademischer Betreuer] Scherr, and Ilka Verena [Akademischer Betreuer] Ott. "Untersuchung von myokardialen Verletzungen und ventrikulärer Funktion bei Marathonläufern in Abhängigkeit von genetischen Parametern / Anna Lisa Berberich. Gutachter: Martin Halle ; Ilka Verena Ott. Betreuer: Martin Halle ; Johannes Scherr." München : Universitätsbibliothek der TU München, 2012. http://d-nb.info/1031551751/34.

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Korycki, Adrian. "Study of the selective laser sintering process : materials properties and effect of process parameters." Thesis, Toulouse, INPT, 2020. https://oatao.univ-toulouse.fr/27651/1/Korycki_Adrian.pdf.

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La fabrication additive permet de répondre aux exigences de réactivité et de rapidité de création d’un produit industriel en réduisant les phases de développement et d’industrialisation. Parmi les technologies prometteuses pour les pièces en thermoplastiques, le procédé de fusion sur lit de poudre (SLS: Selective Laser Sintering) se distingue en raison de sa capacité de réalisation des géométries à faibles tolérances dimensionnelles. Ce procédé est basé sur le déplacement d’un faisceau laser qui interagit avec le lit de poudre. L’attractivité de la fabrication additive contrebalance cependant avec le choix des matériaux actuellement utilisables: ce sont principalement les polyamides. Les polyaryléthercétones (PAEK) adaptés au procédé SLS sont encore rares sur le marché et couteux. Dans ces travaux, différentes poudres ont été caractérisées pour mieux comprendre les propriétés nécessaires à leur utilisation en SLS et définir leur fenêtre de température de processabilité. L'absence de poudre de PEEK adaptée nous a conduit à élaborer un nouveau matériau en mélangeant le PEEK à un thermoplastique amorphe, le polyethersulfone (PESU). Les mélanges initialement immiscibles ont été compatibilisés dans l’objectif d’améliorer leurs propriétés mécaniques et pour retarder leur cristallisation au refroidissement. Pendant la fabrication, de nombreux paramètres du procédé contrôlent la fusion de la poudre, et ainsi les propriétés des pièces et leur précision dimensionnelle. Ainsi, l'analyse statistique de la réponse de l'ensemble des paramètres a fait l’objet d’un plan d’expériences pour en extraire les paramètres les plus influant. L’étude paramétrique, conduite avec la poudre polyamide, a été réalisée en faisant varier cinq paramètres et en regardant leur influence sur cinq groupes de réponses relatives aux propriétés physico-chimiques, physiques, mécaniques et thermiques ainsi qu’aux durées d’impression des pièces. Le plan d’expériences a permis d’établir les modèles mathématiques des surfaces de réponses liant les réponses aux facteurs et à leurs interactions. Ces modèles statistiques ont été utilisés pour définir un jeu de paramètres optimal. Enfin, une approche combinant expérimental et simulation numérique a été menée pour estimer l’influence de chaque passage du laser sur le taux de cristallinité et les propriétés mécaniques de chaque couche. Les résultats montrent que l’échauffement dû aux passages successifs du laser couvre une épaisseur équivalente à 14 couches déposées. Cependant, seules les 4 couches supérieures sont affectées thermiquement de manière significative par le lasage d’une couche de poudre et montrent ainsi une évolution de leur taux de cristallinité
Additive manufacturing is attractive because it allows to reduce significantly the development and industrialization phases of part design. Among the promising technologies for thermoplastic parts, the SLS (Selective Laser Sintering) process stands out because of its ability to produce geometries with low dimensional tolerances. This process is based on the displacement of a laser beam that interacts with the powder bed. The attractiveness of additive manufacturing counterbalances, however, with the choice of currently available materials: these are mainly polyamides. Polyaryletherketones (PAEK) suitable to SLS process are still rare on the market and expensive. In this work, various powders have been characterized to deeper understand the properties necessary for their use in SLS and to define their processability temperature window. The absence of suitable PEEK powder led us to develop a new material by blending PEEK with an amorphous thermoplastic, polyethersulfone (PESU). The initially immiscible blends have been compatibilized in order to improve their mechanical properties and to delay their crystallization on cooling. During manufacturing, many process parameters control the melting of the powder, and thus the properties of the parts and their dimensional accuracy. Thus, a statistical analysis of the response of the parameters was led by a design of experiments to extract the most influential parameters. The parametric study, done with the polyamide powder, was carried out by varying five parameters and by looking at their influence on five groups of responses relating to the physical, mechanical and thermal properties as well as to the printing duration of the parts. The design of experiments made it possible to establish the mathematical models of the response surfaces linking the responses to factors and their interactions. These statistical models were used to define an optimal set of parameters. Finally, a combined experimental and numerical simulation approach was conducted to estimate the influence of each laser pass on the degree of crystallinity and the mechanical properties of each layer. The results show that the heating due to the successive laser passes cover a thickness equivalent to 14 deposited layers. However, only the 4 upper layers are significantly thermally affected by the laser pass on a powder layer and thus show an evolution of their degree of crystallinity

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Ettaieb, Kamel. "Contribution à l'optimisation des stratégies de lagase en fabrication additive LPBF." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLN050.

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Au cours du procédé de fusion laser sur lit de poudre, la température atteinte dans une zone locale est susceptible de générer des gradients thermiques importants. Ces gradients conduisent à leur tour à l'apparition de contraintes résiduelles qui ont un effet sur les caractéristiques mécaniques de la pièce, provoquent des déformations, ainsi que des micro et macro fissures. Dans ce contexte, les trajectoires de lasage jouent un rôle fondamental sur le niveau et la distribution de la température au cours de la fabrication. Il est ainsi nécessaire de valider la génération des trajectoires au regard du comportement thermique induit par ce procédé.Cette thèse propose d'exploiter une méthode analytique pour développer un modèle qui permette d'analyser d'une manière rapide et efficace le comportement thermique dans la pièce lors de la fabrication. En effet, à partir d'une trajectoire de lasage donnée, d'un ensemble de paramètres liés au matériau de la pièce à fabriquer et de paramètres liés au procédé, l'outil développé effectue une simulation de la température en chaque point de la pièce, au cours de temps et de manière rapide, comparée aux autres logiciels de simulation thermique. En effet, afin de réduire le temps de calcul et l'espace mémoire utilisé pour une telle simulation, un ensemble de techniques d'optimisation a été mis en place.Le modèle proposé a été validé dans le cas de l'alliage Ti6Al4V par comparaison avec une simulation thermique par éléments finis obtenue par un logiciel industriel. Ensuite, les résultats de ce modèle sont confrontés aux résultats expérimentaux. Une fois le modèle validé, il a été mis en œuvre pour analyser des trajectoires couramment utilisées dans la littérature et dans l'industrie.Afin de réduire les gradients thermiques et améliorer la qualité des pièces, la solution proposée consiste à contrôler la température et la taille du bain de fusion. Pour se faire, le modèle thermique développé a été exploité pour moduler les paramètres du procédé au cours de la fabrication d'une part et pour développer une stratégie de lasage à pas adaptatif d'autre part
During manufacturing by Laser Powder Bed Fusion (LPBF), the achieved temperatures in local areas could generate significant thermal gradients. These gradients lead to the apparition of residual stresses which affect the mechanical characteristics of the part and may cause deformation, as well as micro and macro cracks. In this context, scanning paths play a fundamental role on temperature level and distribution during manufacturing. For that reason, it is necessary to validate the generation of trajectories considering the thermal behaviour induced by this process.The purpose of this PhD thesis is to use an analytical method in order to develop a model that allows a fast and efficient analysis of thermal behaviour, during part manufacturing. Indeed, with a given scanning path, material properties and process parameters, the developed tool performs a temperature simulation at each point of the part, over time and in a fast way, compared to other thermal simulation software. In order to reduce computation time and memory storage used for such a simulation, a set of optimization techniques has been proposed.The developed model has been validated in the case of the Ti6Al4V alloy through a comparison with a finite element thermal simulation obtained by industrial software. Then, the results of this model were compared to experimental results. Once validated, it has been implemented to analyze trajectories commonly used in the literature and industry.In order to reduce thermal gradients and improve part quality, the proposed solution consists in controlling the temperature and size of melt pool. For this purpose, the developed thermal model has been used to modulate the process parameters during manufacturing on the one hand and to develop an adaptive scanning strategy on the other hand

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Zugárková, Petra. "Vliv intenzity odlistění na kvalitu hroznů." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-190391.

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The aim of this thesis was to establish experiment with different dates of defoliation in the zone of grapes, evaluate the infestation by Botrytis cinerea putrefaction, monitor the development of qualitative and quantitave parametres and the content of phenolic compounds. The experiment was conducted at white wine grapes variety Ryzlink rýnský a blue wine grapes variety Carmenere. The literary section describes leaf and its area, microclimate of leaf walls, qualitative parametres, balance of the vineyard, green works, Botrytis cinerea and partial defoliation. Within the experiment were evaluated and controled at the defoliated variation: quality parameters (sugar content, titratable acid pH, assimilable nitrogen, amount of glucose and fructose, tartaric acid and malic acid), infestation by Botrytis cinerea putrefaction, content of phenolic compounds. Measurements were performed at the Department of viticulture and viniculture in faculty of Horticulture in Lednice. Used instruments: TitroLine - pH, titratable acid, assimilable nitrogen; HPLC - tartaric acid, malic acid, glucose and fructose; Spectrophotometer - the content of phenolic compounds; Digital Scale - weight of the grapes. As the most appropriate option in terms of measured parameters was selected the option before the flowering and during the flowering of Ryzlink rýnský and Carmenere.

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Cohen, Michael Isaac. "Topics in Gravitation – Numerical Simulations of Event Horizons and Parameter Estimation for LISA." Thesis, 2011. https://thesis.library.caltech.edu/5984/1/thesis_mcohen.pdf.

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In Part I, we consider numerical simulations of event horizons. Event horizons are the defining physical features of black hole spacetimes, and are of considerable interest in studying black hole dynamics. Here, we reconsider three techniques to find event horizons in numerical spacetimes, and find that straightforward integration of geodesics backward in time is most robust. We apply this method to various systems, from a highly spinning Kerr hole through to an asymmetric binary black hole inspiral. We find that the exponential rate at which outgoing null geodesics diverge from the event horizon of a Kerr black hole is the surface gravity of the hole. In head-on mergers we are able to track quasi-normal ringing of the merged black hole through seven oscillations, covering a dynamic range of about 10⁵. In the head-on "kick" merger, we find that computing the Landau-Lifshitz velocity of the event horizon is very useful for an improved understanding of the kick behaviour. Finally, in the inspiral simulations, we find that the topological structure of the black holes does not produce an intermediate toroidal phase, though the structure is consistent with a potential re-slicing of the spacetime in order to introduce such a phase. We further discuss the topological structure of non-axisymmetric collisions.

In Part II, we consider parameter estimation of cosmic string burst gravitational waves in Mock LISA data. A network of observable, macroscopic cosmic (super-)strings may well have formed in the early Universe. If so, the cusps that generically develop on cosmic-string loops emit bursts of gravitational radiation that could be detectable by gravitational-wave interferometers, such as the ground-based LIGO/Virgo detectors and the planned, space-based LISA detector. We develop two versions of a LISA-oriented string-burst search pipeline within the context of the Mock LISA Data Challenges, which rely on the publicly available MultiNest and PyMC software packages, respectively. We use the F-statistic to analytically maximize over the signal’s amplitude and polarization, A and ψ, and use the FFT to search quickly over burst arrival times t_C. We also demonstrate an approximate, Bayesian version of the F-statistic that incorporates realistic priors on A and ψ. We calculate how accurately LISA can expect to measure the physical parameters of string-burst sources, and compare to results based on the Fisher-matrix approximation. To understand LISA’s angular resolution for string-burst sources, we draw maps of the waveform fitting factor [maximized over (A, ψ, t_C)] as a function of sky position; these maps dramatically illustrate why (for LISA) inferring the correct sky location of the emitting string loop will often be practically impossible. In addition, we identify and elucidate several symmetries that are embedded in this search problem, and we derive the distribution of cut-off frequencies f_max for observable bursts.

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Blažejová, Aneta. "Morfologické parametry korun dubu letního stg Querci roboris-fraxineta v mikulčickém luhu." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-361956.

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Detection of morphological parameters of trees enables the recognition of its development and helps to better understand the relationships, which occur among them and the surrounding environment. This study deals with the identification of these parameters, particularly the quantification of wood and leaf matter that trees are able to produce. The determined values can be used to identify a lot of other important information regarding the growth of trees and thus contribute to proper forest management.

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VENUŠOVÁ, Alena. "Les constructions causatives \kur{faire + infinitif} et leurs équivalents tch\'ques." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-153302.

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This thesis provides a comparison of causative mechanisms between two languages: Czech and French. The aim of this research is to reveal expressions that contain a causative meaning in Czech and to analyze which of them are truly equivalent to the French causative construction faire + infinitive. This work classifies general causative mechanisms, according to their nature, between synthetic (prefix, lexical expressions) and analytic (French complex predicate faire + infinitive, periphrastic constructions, separate clauses) and focuses on the French construction by describing its syntactical and semantic specificity. This causative construction is the basis of a parallel research in corpora InterCorp, a technical tool which helps excerpt authentic texts. Additionally, it is attempted to clarify and classify the usage of the Czech equivalents and search for factors that influence their choice with an eye on the source language.

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Chirathadam, Thomas A. "Measurements of Drag Torque and Lift Off Speed and Identification of Stiffness and Damping in a Metal Mesh Foil Bearing." Thesis, 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7350.

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Metal mesh foil bearings (MMFBs) are a promising low cost gas bearing technology for support of high speed oil-free microturbomachinery. Elimination of complex oil lubrication and sealing system by installing MMFBs in oil free rotating machinery offer distinctive advantages such as reduced system overall weight, enhanced reliability at high rotational speeds and extreme temperatures, and extended maintenance intervals compared to conventional turbo machines. MMFBs for oil-free turbomachinery must demonstrate adequate load capacity, reliable rotordynamic performance, and low frictional losses in a high temperature environment. The thesis presents the measurements of MMFB break-away torque, rotor lift off and touchdown speeds, temperature at increasing static load conditions, and identified stiffness and equivalent viscous damping coefficients. The experiments, conducted in a test rig driven by an automotive turbocharger turbine, demonstrate the airborne operation (hydrodynamic gas film) of the floating test MMFB with little frictional loses at increasing loads. The measured drag torque peaks when the rotor starts and stops, and drops significantly once the bearing is airborne. The estimated rotor speed for lift-off increases linearly with increasing applied loads. During continuous operation, the MMFB temperature measured at one end of the back surface of the top foil increases both with rotor speed and static load. Nonetheless, the temperature rise is only nominal ensuring reliable bearing performance. Application of a sacrificial layer of solid lubricant on the top foil surface aids to reduce the rotor break-away torque. The measurements give confidence on this simple bearing technology for ready application into oil-free turbomachinery. Impact loads delivered (with a soft tip) to the test bearing, while resting on the (stationary) drive shaft, evidence a system with large damping and a structural stiffness that increases with frequency (max. 200 Hz). The system equivalent viscous damping ratio decreases from ~ 0.7 to 0.2 as the frequency increases. In general, the viscous damping in a metal mesh structure is of structural type and inversely proportional to the frequency and amplitude of bearing motion relative to the shaft. Impact load tests, conducted while the shaft rotates at 50 krpm, show that the bearing direct stiffness is lower (~25% at 200 Hz) than the bearing structural stiffness identified from impact load tests without shaft rotation. However, the identified equivalent viscous damping coefficients from tests with and without shaft rotation are nearly identical. The orbits of bearing motion relative to the rotating shaft show subsynchronous motion amplitudes and also backward synchronous whirl. The subsynchronous vibration amplitudes are locked at a frequency, nearly identical to a rotor natural frequency. A backward synchronous whirl occurs while the rotor speed is between any two natural frequencies, arising due to bearing stiffness asymmetry.

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Tvrdík, Jan. "Efekt kompenzačních cvičení u hráčů ledního hokeje mladšího školního věku se zaměřením na hodnocení vybraných parametrů stability, koordinace a pohybových stereotypů." Master's thesis, 2020. http://www.nusl.cz/ntk/nusl-412179.

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Title: The effect of compensatory exercises in ice hockey players of younger school age with focus on the evaluation of selected parameters of stability, coordination and movement stereotypes Objectives: The objective of this thesis was to verify the effect of compensatory exercises on stability, coordination and movement stereotypes in ice-hockey players of younger school age (8-12 years old). Specifically, the objective was to verify stated effect on dynamic stability, static stability of the trunk, execution of selected stereotypes, coordination and performance in specific test on ice. Methods: Data for this thesis were collected using quantitative form of research. The whole research population was composed of 75 probands with the average age of 10,3 years and who play actively ice-hockey. The population was composed of both sexes, males and females (boys and girls). Participants were divided into two groups - experimental (n = 43) and control (n = 32). To collect the values of measurements was used method of testing with clinical tests and to eliminate disturbing elements we also used the method of questionnaire. The values were collected in input and output sessions. The time spacing between those two measurements was 3 months. Between stated two measurements in experimental group took place...

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