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Dissertations / Theses on the topic 'Hybrid methodology'

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Published: 4 June 2021
Last updated: 27 April 2022

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1

Esgin, Eren. "A Hybrid Methodology In Process Modeling:." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610461/index.pdf.

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The managing of complex business processes, which are changed due to globalization, calls for the development of powerful information systems that offer generic process modeling and process execution capabilities. Even though contemporary information systems are more and more utilized in enterprises, their actual impact in automatizing complex business process is still limited by the difficulties encountered in design phase. Actually this design phase is time consuming, often subjective and incomplete. In the scope of this study, a reverse approach is followed. Instead of starting with process design, the method of discovering interesting patterns from the navigation traces is taken as basis and a new data analysis methodology named &ldquo
From-to Chart Based Process Discovery&rdquo
is proposed. In this hybrid methodology &ldquo
from-to chart&rdquo
, which is fundamentally dedicated to material handling issues on production floor, is used as the front-end to monitor the transitions among activities of a realistic event log and convert these raw relations into optimum activity sequence. Then a revised version of process mining, which is the back-end of this methodology, upgrades optimum activity sequence into process model.
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2

Yu, Bing. "Hybrid modelling methodology for system design." Thesis, Loughborough University, 1995. https://dspace.lboro.ac.uk/2134/6999.

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In the face of rapid development in information technology coupled with a growing dynamism in global markets, manufacturing systems have to be re-constructed for short term or long term goal. Such innovations promise to lead to a new competitive stage, which typically involve design of function, information and behaviour of systems. In order to design the system, simulation has often been chosen. However, simulation has proved limited and fails to aid design of such a complex systems because of consuming much computing time and cost, especially when modelling larger systems. Thus, there is a need to seek a new approach, in a way that results in simulating such a large manufacturing system with less demand on computing time and cost. This study researches into a hybrid modelling approach to minimise these limitations. It includes proposing a hybrid modelling methodology and developing a hybrid modelling tool. The methodology integrates simulation and metamodelling techniques. The metamodel employed in the study possesses, not only characteristics of conventional metamodels in terms of representing relationships in quantity, but also in time lapse. This is the originality of the study and the significant distinction between this research and application of metamodelling in conventional ways. The hybrid modelling tool is developed to support and demonstrate the identified hybrid methodology. LISP has been used as the software language for the hybrid modelling tool. The result of this work concludes that the hybrid modelling approach is capable of simulating a complex manufacturing system with less demands on the computer. The work reported in this thesis has been carried out in conjunction with the EPSRC research project, Hierarchical Manufacturing System Modelling (HMSM) (GR/F96549), to produce an Integrated Design and Modelling Methodology (IDEM). The project was initially a collaborative research program including Loughborough University of Technology (LUT), Morris Crane Ltd., of Loughborough and GEC Large Machine, of Rugby. The experience of these collaborators has proved most valuable in supporting the research, and have provided a cross section of views and comments. The research reported in this thesis is set in the context of the HMSM Research group at Loughborough.
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3

Tyree, Eric William. "A hybrid methodology for data clustering." Thesis, City University London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301057.

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4

Wang, Chengdong. "Hybrid causal logic methodology for risk assessment." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/7729.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.
Thesis research directed by: Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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5

Bin, Hasnan Khalid. "Methodology to develop hybrid simulation/emulation model." Thesis, Sheffield Hallam University, 2005. http://shura.shu.ac.uk/19768/.

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Trends towards reduced life-time of products and globalised competition has increased pressure on manufacturing industries to be more responsive to changing needs of product markets. Consequently, the use of simulation to describe short term future performance of manufacturing system has become more significant than ever. An application of simulation that has attracted attention is for testing of control logic before commissioning on site by using a detailed simulation model called emulation model. However, though the success of using emulation particularly in improving cost-effectiveness of automated material handling system delivery has been acknowledged by industries and simulation model developers, the uptake for this technology is still low. The major inhibitors are the high costs of its model building as well as simulation and emulation models are perceived to be non convertible. The main objective, of this research is to establish a methodology to develop simulation model that can be converted into emulation model with ease, thus making emulation technology more affordable. The product of this research called the methodology to build Hybrid Simulation Emulation Model (HSEM) is a new approach of building emulation model comprising of three phases namely (1) development of base simulation model, (2) development of detail emulation model, and (3) integration of controller with the emulation model. Important requirements for HSEM are flexibility of adding details to the simulation model and inter process communication between model and real control system. To facilitate implementation of the methodology, it is essential that the simulation software package provide functionalities for modular model development, access and adding of codes, integration with other application and real time (RT) modelling. The methodology developed offers a more affordable emulation modelling and an opening for further research into the comprehensive support for the implementation of real time control system testing using emulation.
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6

Burman, Emil. "Agile in action : Hybrid methodologies in practice." Thesis, Umeå universitet, Institutionen för informatik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-107894.

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In recent years an increase of agile methodologies and their implementation in mainstream software engineering projects have been seen, but this implementation has reportedly changed agility in practice into a hybrid form of agility and more classic methodologies. With a lack of research regarding these hybrid methodologies this multiple case study empirically analyses the practice of methodologies from two different conglomerates and places the results in the Information Technology Management framework (ITMF) to answer the research question; How are hybrid agile methodologies enacted in practice in mature agile teams and why are they enacted in such a way? The result show that the organizations work agile within a waterfall framework, a hybrid form of requirement handling into agile development followed by waterfall testing. The hybrid methodologies are imposed by external factors such as the sales department and traditional economic reporting. This study acknowledges a need for a greater understanding of the engagement between external actors and software development.
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7

Kim, Intaek. "A Hybrid analytical/intelligent methodology for sensor fusion." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/13743.

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8

Sarh, Bastian. "A novel hybrid joining methodology for composite to steel joints /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3205377.

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9

Kabalan, Bilal. "Systematic methodology for generation and design of hybrid vehicle powertrains." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSE1048.

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Pour répondre aux objectifs de consommation des flottes de véhicules, au normes d’émissions de polluants et aux nouvelles demandes de l’usager, les constructeurs automobiles doivent développer des motorisations hybrides et électriques. Réaliser une chaine de traction hybride reste cependant une tâche difficile. Ces systèmes sont complexes et possèdent de nombreuses variables réparties sur différents niveaux : architecture, technologie des composants, dimensionnement et contrôle/commande. L’industrie manque encore d’environnements et d’outils pouvant aider à l’exploration de l’ensemble de l’espace de dimensionnement et à trouver la meilleure solution parmi tous ces niveaux. Cette thèse propose une méthodologie systématique pour répondre au moins partiellement à ce besoin. Partant d’un ensemble de composants, cette méthodologie permet de générer automatiquement tous les graphes d’architectures possibles en utilisant la technique de programmation par contraintes. Une représentation dédiée est développée pour visualiser ces graphes. Les éléments de boites de vitesse (embrayages, synchroniseurs) sont représentés avec un niveau de détails approprié pour générer de nouvelles transmission mécaniques sans trop complexifier le problème. Les graphes obtenus sont ensuite transformés en d’autres types de représentation : 0ABC Table (décrivant les connections mécaniques entre les composants), Modes Table (décrivant les modes de fonctionnement disponibles dans les architectures) et Modes Table + (décrivant pour chaque mode le rendement et le rapport de réduction global des chemins de transfert de l’énergie entre tous les composants). Sur la base de cette représentation, les nombreuses architectures générées sont filtrées et seules les plus prometteuses sont sélectionnées. Elles sont ensuite automatiquement évaluées et optimisées avec un modèle général spécifiquement développé pour calculer les performances et la consommation de toute les architectures générées. Ce modèle est inséré dans un processus d’optimisation à deux niveaux ; un algorithme génétique GA est utilisé pour le dimensionnement des composants et la programmation dynamique est utilisée au niveau contrôle (gestion de l’énergie) du système. Un cas d’étude est ensuite réalisé pour montrer le potentiel de cette méthodologie. Nous générons ainsi automatiquement toutes les architectures qui incluent un ensemble de composants défini à l’avance, et le filtrage automatique élimine les architectures présupposées non efficaces et sélectionnent les plus prometteuses pour l’optimisation. Les résultats montrent que la méthodologie proposée permet d’aboutir à une architecture meilleure (consommation diminuée de 5%) que celles imaginées de prime abord (en dehors de toute méthodologie)
To meet the vehicle fleet-wide average CO2 targets, the stringent pollutant emissions standards, and the clients’ new demands, the automakers realized the inevitable need to offer more hybrid and electric powertrains. Designing a hybrid powertrain remains however a complex task. It is an intricate system involving numerous variables that are spread over different levels: architecture, component technologies, sizing, and control. The industry lacks frameworks or tools that help in exploring the entire design space and in finding the global optimal solution on all these levels. This thesis proposes a systematic methodology that tries to answer a part of this need. Starting from a set of chosen components, the methodology automatically generates all the possible graphs of architectures using constraint-programming techniques. A tailored representation is developed to picture these graphs. The gearbox elements (clutches, synchronizer units) are represented with a level of details appropriate to generate the new-trend dedicated hybrid gearboxes, without making the problem too complex. The graphs are then transformed into other types of representation: 0ABC Table (describing the mechanical connections between the components), Modes Table (describing the available modes in the architectures) and Modes Table + (describing for each available mode the global efficiency and ratio of the power flow between all the components). Based on these representations, the architectures are filtered and the most promising ones are selected. They are automatically assessed and optimized using a general hybrid model specifically developed to calculate the performance and fuel consumption of all the generated architectures. This model is inserted inside a bi-level optimization process: Genetic Algorithm GA is used on the sizing and components level, while Dynamic Programming DP is used on the control level. A case study is performed and the capability of the methodology is proven. It succeeded in automatically generating all the graphs of possible architectures, and filtering dismissed architectures that were then proven not efficient. It also selected the most promising architectures for optimization. The results show that the proposed methodology succeeded in finding an architecture better than the ones proposed without the methodology (consumption about 5% lower)
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10

Spivak, Alexander. "A Theoretical Model for Life Cycle Inventory Analysis using a Disaggregated Hybrid Methodology." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1310035001.

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11

佘錦炎 and Kam-yim Sze. "Development of efficient and robust hybrid/mixed elements for solid structures." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31231974.

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12

Rajmohan, Nischint. "Application of hybrid methodology to rotors in steady and maneuvering flight." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34756.

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Helicopters are versatile flying machines that have capabilities that are unparalleled by fixed wing aircraft, such as operating in hover, performing vertical take-off and landing on unprepared sites. However, modern helicopters still suffer from high levels of noise and vibration caused by the physical phenomena occurring in the vicinity of the rotor blades. Therefore, improvement in rotorcraft design to reduce the noise and vibration levels requires understanding of the underlying physical phenomena, and accurate prediction capabilities of the resulting rotorcraft aeromechanics. The goal of this research is to study the aeromechanics of rotors in steady and maneuvering flight using hybrid Computational Fluid Dynamics (CFD) methodology. The hybrid CFD methodology uses the Navier-Stokes equations to solve the flow near the blade surface but the effect of the far wake is computed through the wake model. The hybrid CFD methodology is computationally efficient and its wake modeling approach is non-dissipative making it an attractive tool to study rotorcraft aeromechanics. Several enhancements were made to the CFD methodology and it was coupled to a Computational Structural Dynamics (CSD) methodology to perform a trimmed aeroelastic analysis of a rotor in forward flight. The coupling analyses, both loose and tight were used to identify the key physical phenomena that affect rotors in different steady flight regimes. The modeling enhancements improved the airloads predictions for a variety of flight conditions. It was found that the tightly coupled method did not impact the loads significantly for steady flight conditions compared to the loosely coupled method. The coupling methodology was extended to maneuvering flight analysis and the flight test control angles were employed to enable the maneuvering flight analysis. The fully coupled model provided the presence of three dynamic stall cycles on the rotor in maneuver. Analysis of maneuvering flight requires knowledge of the pilot input control pitch settings, and the vehicle states. As the result, these computational tools cannot be used for analysis of loads in a maneuver that has not been duplicated in a real flight. This is a significant limitation if these tools are to be selected during the design phase of a helicopter where its handling qualities are evaluated in different trajectories. Therefore, a methodology was developed to couple the CFD/CSD simulation with an inverse flight mechanics simulation to perform the maneuver analysis without using the flight test control input. The methodology showed reasonable convergence in steady and maneuvering flight regimes and control angle predictions compared fairly well with test data. In the maneuvering flight regions, the convergence was slower due to relaxation techniques used for the numerical stability. Further, the enhancement of the rotor inflow computations in the inverse simulation through implementation of a Lagrangean wake model improved the convergence of the coupling methodology.
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13

Chen, Xin. "Towards an integrated methodology for the development of hybrid information systems." Thesis, University of Sunderland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263000.

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Our modern information society has produced many sophisticated requirements for the development of information systems. A new challenge is the study of hybrid information systems that combine traditional information systems with knowledge-based systems. This new generation information system is considerably more powerful than a simple extrapolation of existing system concepts. It is easy to imagine the advantages of powerful knowledge-based systems with efficient access to several large databases, and of large traditional information systems with added intelligence. Due to the complex nature of hybrid information systems, it is umealistic to expect that they can be developed using one standard method. The use of several independently developed methods has a number of drawbacks, such as inconsistency, redundancy, amount of effort required and possible loss of information. In an attempt to provide at least a partial solution to this problem. this thesis describes a new integrated methodology for developing hybrid information systems. This methodology combines the method for developing traditional information systems with the method for developing knowledge-based systems. The new methodology provides a hybrid lifecycle process model to combine the conventional waterfall process with rapid prototyping and model-based approaches. The proposed methodology integrates four eXlstmg methods using two integration approaches: intra-process and inter-process. In the requirements analysis phase. a structured method is applied to function analysis, an information modelling method is applied to data analysis, and a knowledge acquisition method is applied to knowledge analysis. An intraprocess approach is then used to integrate these techniques using consistency rules. In the design phase. the new methodology uses an inter-process approach to transform requirements analysis to object-oriented design by a transformation algorithm. Finally, an object-oriented method is applied to the design and implementation of hybrid information systems. Using the new methodology, a hybrid medical information system for dizziness (HMISD) was developed, which combines components of traditional medical information systems with components of medical expert systems. The construction and development of this software are described in detail. The system can support activities in hospitals including registration, diagnosis, investigations, drug management and clinical research. It provides assistance to hospital doctors and general practitioners. The performance of HMISD is evaluated by testing ninety three real patient cases and taking two investigations from medical staff and patients. The evaluation results show that HMISD is of good quality and that most of its users are satisfied. Three approaches are used to evaluate the proposed methodology: analysis of the development of HMISD, comparison with existing methodologies using CMD and expert evaluations. The evaluation conclusions indicate that this new integrated methodology can take advantage of the four existing methods and also remove some of the limitations of each individual method. It is applicable to the development of traditional information systems, knowledge-based systems, and large and complex hybrid information systems.
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14

Grey, Johannes. "The development of a hybrid agile project management methodology / Grey, J." Thesis, North-West University, 2011. http://hdl.handle.net/10394/7004.

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The aim of this study is to investigate whether a combination of agile system development methodologies (ASDMs) and project management methodologies (PMMs) can be used to develop a hybrid APMM that will have the ability to deliver information technology (IT) projects successfully in a constantly changing business and project environment. To achieve this objective, a literature review was conducted on the relatively well–established ASDMs by firstly defining a SDM and an ASDM. Each ASDM and its effectiveness are described, after which ASDMs in general are evaluated by considering their area of application, advantages and disadvantages. A comparison is then done of the seven different ASDMs using the four elements of an SDM (Huisman & Iivari, 2006:32) to emphasise some of the main similarities and differences amongst the different ASDMs. The seven ASDMs investigated in this study are Dynamic System Development Methodology, Scrum, Extreme Programming, Feature Driven Development, Crystal ASDMs ? Crystal Clear and Crystal Orange in particular, Adaptive Software Development and Lean Development. A literature review was also conducted on two structured and relatively well–established PMMs, PMBOK and PRINCE2, and a relatively new PMM called Agile Project Management. Each PMM is evaluated by considering their area of application, advantages, disadvantages and integration with other methodologies, after which a comparison is made of the different PMMs. The research was conducted by following a mixed methods research plan, which included the mixed methods research paradigm (combination of the interpretive research paradigm and the positivistic research paradigm), research methods (design science, case study and survey), quantitative and qualitative data–collection techniques (interviews and questionnaires), and dataanalysis techniques (cross–case and statistical). The reasons that projects fail and critical project success factors were studied and summarised to form the critical project success criteria, which were used to create the agile project success criteria. The ASDM best practice and PMM best practice frameworks were created by identifying whether a certain ASDM or PMM would satisfy a specific agile project success factor (APSF) of the agile project success criteria. The findings of each APSF in the respective frameworks were used as a foundation to develop a hybrid APMM (ver. 0) that would address the agile project success criteria. The hybrid APMM (ver. 0) was developed interpretively using design science (research approach) and constructivism by combining the strengths, addressing the weaknesses and bridging the gaps identified in the frameworks. The hybrid APMM (ver. 0) was then evaluated and improved by conducting an interpretive case study, which entailed interviewing participants from large and small organisations. Once the qualitative data collected had been analysed using cross–case analysis, the findings were incorporated in order to create an improved hybrid APMM (ver. 1). The hybrid APMM (ver. 1) too was evaluated and improved by conducting a survey, which entailed administering questionnaires to various respondents in order to collect quantitative and qualitative data. The findings of the statistical analysis of the data were also used to improve the hybrid APMM (ver. 1), resulting in the final hybrid APMM (ver. 2). This study demonstrates that a combination of ASDMs and PMMs can be used to develop a hybrid APMM with the ability to deliver IT projects in a constantly changing project and business environment.
Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2012.
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15

Quijada, Sergio. "A HYBRID SIMULATION METHODOLOGY TO EVALUATE NETWORK CENTRICDECISION MAKING UNDER EXTREME EVENTS." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2348.

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Currently the network centric operation and network centric warfare have generated a new area of research focused on determining how hierarchical organizations composed by human beings and machines make decisions over collaborative environments. One of the most stressful scenarios for these kinds of organizations is the so-called extreme events. This dissertation provides a hybrid simulation methodology based on classical simulation paradigms combined with social network analysis for evaluating and improving the organizational structures and procedures, mainly the incident command systems and plans for facing those extreme events. According to this, we provide a methodology for generating hypotheses and afterwards testing organizational procedures either in real training systems or simulation models with validated data. As long as the organization changes their dyadic relationships dynamically over time, we propose to capture the longitudinal digraph in time and analyze it by means of its adjacency matrix. Thus, by using an object oriented approach, three domains are proposed for better understanding the performance and the surrounding environment of an emergency management organization. System dynamics is used for modeling the critical infrastructure linked to the warning alerts of a given organization at federal, state and local levels. Discrete simulations based on the defined concept of "community of state" enables us to control the complete model. Discrete event simulation allows us to create entities that represent the data and resource flows within the organization. We propose that cognitive models might well be suited in our methodology. For instance, we show how the team performance decays in time, according to the Yerkes-Dodson curve, affecting the measures of performance of the whole organizational system. Accordingly we suggest that the hybrid model could be applied to other types of organizations, such as military peacekeeping operations and joint task forces. Along with providing insight about organizations, the methodology supports the analysis of the "after action review" (AAR), based on collection of data obtained from the command and control systems or the so-called training scenarios. Furthermore, a rich set of mathematical measures arises from the hybrid models such as triad census, dyad census, eigenvalues, utilization, feedback loops, etc., which provides a strong foundation for studying an emergency management organization. Future research will be necessary for analyzing real data and validating the proposed methodology.
Ph.D.
Other
Engineering and Computer Science
Modeling and Simulation
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16

Eker, Ömer F. "A hybrid prognostic methodology and its application to well-controlled engineering systems." Thesis, Cranfield University, 2015. http://dspace.lib.cranfield.ac.uk/handle/1826/9269.

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This thesis presents a novel hybrid prognostic methodology, integrating physics-based and data-driven prognostic models, to enhance the prognostic accuracy, robustness, and applicability. The presented prognostic methodology integrates the short-term predictions of a physics-based model with the longer term projection of a similarity-based data-driven model, to obtain remaining useful life estimations. The hybrid prognostic methodology has been applied on specific components of two different engineering systems, one which represents accelerated, and the other a nominal degradation process. Clogged filter and fatigue crack propagation failure cases are selected as case studies. An experimental rig has been developed to investigate the accelerated clogging phenomena whereas the publicly available Virkler fatigue crack propagation dataset is chosen after an extensive literature search and dataset analysis. The filter clogging experimental rig is designed to obtain reproducible filter clogging data under different operational profiles. This data is thought to be a good benchmark dataset for prognostic models. The performance of the presented methodology has been evaluated by comparing remaining useful life estimations obtained from both hybrid and individual prognostic models. This comparison has been based on the most recent prognostic evaluation metrics. The results show that the presented methodology improves accuracy, robustness and applicability. The work contained herein is therefore expected to contribute to scientific knowledge as well as industrial technology development.
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17

Alam, Mohammad Faridul. "A dynamic hybrid RANS/LES modeling methodology for turbulent/transitional flow field prediction." Thesis, Mississippi State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3603414.

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A dynamic hybrid Reynolds-averaged Navier-Stokes (RANS)-Large Eddy Simulation (LES) modeling framework has been investigated and further developed to improve the Computational Fluid Dynamics (CFD) prediction of turbulent flow features along with laminar-to-turbulent transitional phenomena. In recent years, the use of hybrid RANS/LES (HRL) models has become more common in CFD simulations, since HRL models offer more accuracy than RANS in regions of flow separation at a reduced cost relative to LES in attached boundary layers. The first part of this research includes evaluation and validation of a dynamic HRL (DHRL) model that aims to address issues regarding the RANS-to-LES zonal transition and explicit grid dependence, both of which are inherent to most current HRL models. Simulations of two test cases—flow over a backward facing step and flow over a wing with leading-edge ice accretion—were performed to assess the potential of the DHRL model for predicting turbulent features involved in mainly unsteady separated flow. The DHRL simulation results are compared with experimental data, along with the computational results for other HRL and RANS models. In summary, these comparisons demonstrate that the DHRL framework does address many of the weaknesses inherent in most current HRL models.

Although HRL models are widely used in turbulent flow simulations, they have limitations for transitional flow predictions. Most HRL models include a fully turbulent RANS component for attached boundary layer regions. The small number of HRL models that do include transition-sensitive RANS models have issues related to the RANS model itself and to the zonal transition between RANS and LES. In order to address those issues, a new transition-sensitive HRL modeling methodology has been developed that includes the DHRL methodology and a physics-based transition-sensitive RANS model. The feasibility of the transition-sensitive dynamic HRL (TDHRL) model has been investigated by performing numerical simulations of the flows over a circular cylinder and a PAK-B airfoil. Comparisons with experimental data along with computational results from other HRL and RANS models illustrate the potential of TDHRL model for accurately capturing the physics of complex transitional flow phenomena.

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18

Tyler, Laurence Gethyn. "A hybrid methodology for the experimental study of collective behaviour in robot groups." Thesis, De Montfort University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420853.

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19

Ojala, E. (Eetu). "Addressing initial customer inquiries with a hybrid team using agile project management methodology." Master's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201801101043.

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The paper is a case study with Patria Land (the Company) as a client. The phenomenon behind the research is the complexity of choosing the “right” customers for doing business with. This is the case with virtually every company, not just the client of this paper. The research problem in this research is “How can the Company develop a rigorous and unambiguous internal process for addressing the initial inquiries from potential customers?” To provide an answer to the set problem, there are two additional research questions, which are “What happens within the Company when an initial inquiry comes in?” and “What does creating an unambiguous process for addressing the initial inquiries from potential customers require from the Company?” Because of the complexity of the subject as well as the problem being quite company-specific, there were not any ready-made solutions or theories to be applied. Therefore, providing a solution for the research problem required combining different theories with each other. For the empirical nature of the problem, action research was chosen to be used as a method of conducting this research. The theoretical approach included comparing traditional project management procedures with agile ones and what are the reasons why agile project management should be used in providing an answer for the research problem in this research. In addition to this comparison, the communication aspect was determined as being one of the challenges of the Company. Thus, the concept of business communication is covered in this paper. Bringing the business communication of the Company up-to-date was chosen to be done with the help of mobile applications and a company called AppGyver is used as an example of such provider in this paper. Lastly, the process that is created in the paper is based on using the concept of a hybrid team and therefore it is covered in detail. Because of the empirical nature of the research problem, interviewing certain key employees of the Company was deemed as being the best method of gathering the empirical data. The interviews were qualitative, semi-structured by nature and were conducted as ethnographic interviews. The conclusions of the paper are that the Company did not have an unambiguous process for addressing the initial inquiries from potential customers and it was highly dependent on the person getting the inquiry how it was addressed. As for what does it require to create an unambiguous process for addressing the initial inquiries, it was determined that the Company needs to have a hybrid quotation team that uses specific mobile applications to improve things such as communication and operates according to the agile project management methodology. The actual process created for addressing the initial inquiries is based on forming the said hybrid quotation team. The process has five different stages that are: 1. Initial inquiry comes in, 2. The inquiry is directed to the hybrid quotation team and is evaluated by the team, 3. Deciding on whether to start the quotation process, 4. Quotation process and 5. Decision from the customer.
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Baugher, Skyler Keil. "Development of a Hybrid Methodology for RANS and LES Modeling of Aerodynamic Flows." University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1588873661973254.

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21

Al-Tarawneh, Alalddin T. "Towards a new methodology for translating the Quran into English : a hybrid model." Thesis, Queen's University Belfast, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705637.

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The belief that the Quran is the literal word of God (Allah) in Arabic is fundamental to every Muslim. It is also a frightening notion that haunts many Quran translators. It often drives them to translate the Quran literally, in a way, thinking that this is the best way to maintain faithfulness to the sacred text, despite the fact that they are aware that the translation itself is not sacred. As a result, many of the Quran translations are stained by this excessive literalness to a degree that they are quoted and effectively used against Islam and Muslims. Consequently, this research project is concerned with developing a new methodology for undertaking Quran translation that brings together a variety of techniques to represent the Quran in a way that may be considered more communicative and favourably received by the target readers. First, two factors are introduced to guide the process of translation: the need to set a target - skopos - that shapes the output of the overall process, and the need to consult existing Quran exegesis for interpretation so as to limit, as far as possible, individual translator influence. The methodology used to translate the Quran is presented in a hybrid model whose ultimate aim is to convey the meaning of the source text (ST) as it is generated within its context - that is, not in terms of its surface semantics - and to provide a target text (TT) that serves native speakers of English, regardless of their faith backgrounds. 1 chose one chapter of the Quran - “Mary” - as a sample translation. A reception study that supplied positive feedback from the intended audience of this research confirmed the validity and reliability of the model. The research has also confirmed that the translation is more informative than the original text to its proposed target readership. The research is indeed prescriptive in that it seeks to propose a translation through a systematic and organised treatment of the very special text that is the original. The ultimate concern is that the language of the translated text be domesticated according to target language norms, at the same time leaving intact the distinct foreign elements located in the ST because their distinctiveness is crucial to its identity.
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Parekh, Rutu. "Simulation and design methodology for hybrid SET-CMOS logic at room temperature operation." Thèse, Université de Sherbrooke, 2012. http://hdl.handle.net/11143/6137.

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The purpose of this thesis is to research the possibility of realizing hardware support for hybrid single electron transistor (SET)-CMOS circuits by a systematic approach of design, analysis and simulation. The metallic SET transistors considered in this work are fabricated within the chip interconnect layers using CMOS back-end-of-line (BEOL)-compatible processing. The CMOS process integration can be divided into front-end-of-line (FEOL) and BEOL processes. The FEOL includes processes required to form isolated CMOS transistors whereas BEOL is the second portion of the IC fabrication where the devices get interconnected through the wiring using multiple layers of dielectrics and metals. Therefore, metallic SET circuits can be easily stacked above the CMOS platform presenting a low cost, low thermal budget, improving the overall yield at high-volume production of highly integrated systems. This considerably decreases the interconnect parasitics and increases the density of functions while maintaining the overall acceptable performance. Many problems such as low current drivability, delay and small voltage gain that hinder SET technology for its implementation in integrated circuits can be alleviated by intelligent circuit design. Although a complete replacement of CMOS by SETs is unlikely in the near future, an augmentation of CMOS with SETs is desirable if interfacing from and to CMOS works well. Interfacing from CMOS to SET circuitry is simple as the current and voltage levels are small and in accessible range. But interfacing CMOS from SET circuits is delicate due to SET logic's low current driving capability for CMOS and its interconnect. There is no concrete research on the interface issue wherein a SET-only circuitry drives a CMOS and its interconnects. For such hybridization to become possible, it is necessary to demonstrate the SET logic driving capability for CMOS with sufficient current drive and output voltage. The core SET logic can be designed to operate at low voltage, but at the interface the output of the SET logic must be in a voltage range that can be fed to a CMOS input for proper logic functionality. It is hence necessary to develop and adopt a systematic design methodology for such hybrid circuits at a specific technology node for room temperature operation. In this thesis we will look at a generalized design methodology that can be applied to (a) develop a fabrication model with parasitic effect of a hybrid SET-CMOS and SET-only circuits, (b) design and analyze the SET based fundamental building block in hybrid SET-CMOS or SET-only circuit and (c) simulate such a circuitry to assess its merits. More specifically, we will address the interfacing issue of such hybrid circuits in which we exploit the maximum capability of a SET logic in terms of driving capability, voltage response and power for a room temperature operation. The result of this research motivates the application of SET logic in 2 stages realizing some properties beyond those of CMOS devices. The first stage is the heterogeneous integration at chip level around a CMOS core. In such a circuitry, the SET introduces new functionalities such as reconfigurable logic, random number-based circuits, and multiband filtering circuits that can be combined with CMOS based general purpose processors or I/O signal restoration. The second stage of application is to use a new information processing technology focussed on a "new switch" exploiting a new state variable to provide functional scaling substantially beyond that attainable solely with ultimately scaled CMOS.
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Apte, Manoj Shriganesh. "An operating system architecture and hybrid scheduling methodology for real-time systems with uncertainty." Diss., Mississippi State : Mississippi State University, 2004. http://library.msstate.edu/etd/show.asp?etd=etd-11102004-152431.

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Vedovoto, João Marcelo. "Mathematical and numerical modeling of turbulent reactive flows using a hybrid LES/PDF methodology." Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2011. http://www.theses.fr/2011ESMA0015.

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Ce travail de thèse est consacré au développement d'une approche numérique permettant de conduire des simulations "low Mach number" d'écoulements réactifs. L'algorithme d'intégration retenu pour procéder à la résolution des équations de transport repose sur une méthode implicite de prédiction-correction (méthode de projection). Une contrainte physique est retenue pour garantir que le champ de vitesse est résolue correctement. Le code de calcul est soumis à plusieurs séries de vérifications préliminaires basées sur l'emploi de la méthode solution manufacturées pour des conditions incompressibles d'abord puis à masse volumique variable qui permettent de statuer quant à la bonne implémentation des schémas numériques retenus. Les performances de l'outil numérique en terme de stabilité et de robustesse sont elles-aussi analysées dans des situations simples : couche de mélange à densité variable en développement spatial et temporel. Le modèle numérique final repose sur l'emploi d'une méthode hybride LES/PDF. Pour ce qui concerne la représentation de la turbulence, deux fermetures sont implémentées pour représenter l'effet des fluctuations de vitesse non résolues. Il s'agit du modèle de Smagorinsky dans sa version dynamique ou non. La spécification de conditions aux limites turbulentes réalistes est elle-aussi analysée en détail et trois approches différentes sont considérées. Pour ce qui concerne la combustion, l'influence des fluctuations de composition aux échelles non résolues est pris en compte par le biais d'une résolution de la PDF scalaire de sous maille. Le modèle de PDF correspondant repose sur l'emploi d'une méthode de Monte Carlo. Des équations différentielles stochastiques, équivalentes aux équations de Fokker-Planck, sont résolues pour la variable de progrès de la réaction chimique. L'objectif final est aussi de pouvoir procéder, à moyen terme, à des simulations LES en géométries complexes et l'emploi du calcul distribué est essentiel. De ce point de vue, la méthode de décomposition de domaine retenue dans ce travail montre des niveau de performances relativement satisfaisants. Les capacités du modèle numérique résultant de ces développements sont illustrées sur deux configurations expérimentales. La première géométrie correspond à un écoulement très fortement turbulent de réactifs pré-mélangés dans un canal bidimensionnel. La seconde correspond à un jet rapide et non confiné de réactifs pré-mélangés
The present work is devoted to the development and implementation of a computational framework to perform numerical simulations of low Mach number turbulent reactive flows. The numerical algorithm designed for solving the transport equations relies on a fully implicit predictor-corrector integration scheme. A physically consistent constraint is retained to ensure that the velocity field is solved correctly, and the numerical solver is extensively verified using the Method of Manufactured Solutions (MMS) in both incompressible and variable-density situations. The final computational model relies on a hybrid Large Eddy Simulation / transported Probability Density Function (LES-PDF) framework. Two different turbulence closures are implemented to represent the residual stresses: the classical and the dynamic Smagorinsky models. The specification of realistic turbulent inflow boundary conditions is also addressed in details, and three distinct methodologies are implemented. The crucial importance of this issue with respect to both inert and reactive high fidelity numerical simulations is unambiguously assessed. The influence of residual sub-grid scale scalar fluctuations on the filtered chemical reaction rate is taken into account within the Lagrangian PDF framework. The corresponding PDF model makes use of a Monte Carlo technique: Stochastic Differential Equations (SDE) equivalent to the Fokker-Planck equations are solved for the progress variable of chemical reactions. With the objective of performing LES of turbulent reactive flows in complex geometries, the use of distributed computing is mandatory, and the retained domain decomposition algorithm displays very satisfactory levels of speed-up and efficiency. Finally, the capabilities of the resulting computational model are illustrated on two distinct experimental test cases: the first is a two-dimensional highly turbulent premixed flame established between two streams of fresh reactants and hot burnt gases which is stabilized in a square cross section channel flow. The second is an unconfined high velocity turbulent jet of premixed reactants stabilized by a large co-flowing stream of burned products
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Siddens, Aaron Jeffrey. "A Predictive Methodology for Soft Impact Damage in Jet Engines Incorporating Hybrid Composite Structures." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/76957.

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This work presents a detailed predictive modeling methodology for comprehensive crashworthiness analysis of advanced jet engine forward sections, containing hybrid and composite structures, when subjected to soft impact. Bird strike onto the fan assembly is chosen as the impact event to be studied. The aim is to develop a numerical methodology capable of accurately capturing the full range of multifaceted damage in hybrid and composite structures as they evolve throughout the forward section of a propulsion system. Effective strategies are developed within an explicit finite element framework for modeling a bird, an engine forward section, intra-ply and inter-ply composite damage, and hybrid structural failure. The accuracy of each approach and their numerical modeling considerations are thoroughly investigated. These techniques are then combined to form the full crashworthiness methodology. It is demonstrated that the complete methodology effectively captures progressive hybrid fan blade fracture, leading edge de-bonding, composite casing delamination, and other significant progressive damage effects caused by direct impact and subsequent engine component interactions. The full damage prognosis capabilities demonstrated by this approach encompass aspects which have remained mainly unaddressed in soft impact analysis. A methodology for assessing the complete extent of impact damage for advanced structural engine designs represents a breakthrough that can contribute greatly to the rapid development of these systems in the future.
Master of Science
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Lating, Peter Okidi. "Hybrid e-learning for Rural Secondary Schools in Uganda." Licentiate thesis, Karlskrona : Blekinge Institute of Technology, School of Technoculture, Humanities and Planning, 2006. http://www.bth.se/fou/Forskinfo.nsf/allfirst2/55ff6c6b8b6dbd62c1257248004a52ef?OpenDocument.

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Hamwi, Khawla. "Low Power Design Methodology and Photonics Networks on Chip for Multiprocessor System on Chip." Thesis, Brest, 2013. http://www.theses.fr/2013BRES0029.

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Les systèmes multiprocesseurs sur puce (MPSoC)s sont fortement émergent comme principaux composants dans les systèmes embarqués à hautes performances. La principale complexité dans la conception et l’implémentation des MPSoC est la communication entre les cœurs. Les réseaux sur puce (NoC) sont considérés comme la solution pour cet effet. ITRS prédit que des centaines de cœurs seront utilisées dans la génération future de système sur puce (SoC), ce qui va donc augmenter les coûts de l’évolutivité, de bande passante et de l’implémentation des réseaux sur puce (NoC)s. Ces problèmes sont présents dans diverses tendances technologiques dans le domaine des semiconducteurs et de la photonique. Cette thèse préconise l'utilisation de la synthèse NoC comme l'approche la plus appropriée pour exploiter ces tendances technologiques et rattraper les exigences des applications. A partir de plusieurs méthodologies de conception basées sur la technologie FPGA et des techniques d'estimation basse énergie (HLS) pour plusieurs IPs, nous proposons une implémentation ASIC basée sur la technologie 3D Tezzaron. Multi-FPGA technologie est utilisée pour valider la conception MPSoC avec 64 processeurs Butterfly NoC. La synthèse NoC est basée sur le regroupement de maîtres et d’esclaves générant des architectures asymétriques avec un soutien approprié pour les demandes très haut débit par optique NoC (ONoC), tandis que les demandes de bande passante inférieure sont traitées par électronique NoC. Une programmation linéaire est proposée comme une solution pour la synthèse NoC
Multiprocessor systems on chip (MPSoC)s are strongly emerging as main components in high performance embedded systems. Several challenges can be determined in MPSoC design like the challenge which comes from interconnect infrastructure. Network-on-Chip (NOC) with multiple constraints to be satisfied is a promising solution for these challenges. ITRS predicts that hundreds of cores will be used in future generation system on chip (SoC) and thus raises the issue of scalability, bandwidth and implementation costs for NoCs. These issues are raised within the various technological trends in semiconductors and photonics. This PhD thesis advocates the use of NoC synthesis as the most appropriate approach to exploit these technological trends catch up with the applications requirements. Starting with several design methodologies based on FPGA technology and low power estimation techniques (HLS) for several IPs, we propose an ASIC implementation based on 3D Tezzaron technology. Multi-FPGA technology is used to validate MPSoC design with up to 64 processors with Butterfly NoC. NoC synthesis is based on a clustering of masters and slaves generating asymmetric architectures with appropriate support for very high bandwidth requests through Optical NoC (ONoC) while lower bandwidth requests are processed by electronic NoC. A linear programming is proposed as a solution to the NoC synthesis
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Wong, Kim Fay. "Refinement of hybrid mixed quantum-classical methodology for chemical dynamics in solutions and molecular materials /." Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3064688.

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Araujo, Luiz Jonatã Pires de. "A hybrid methodology to solve the container loading problem with weight distribution and cutting problems." Universidade de Fortaleza, 2011. http://dspace.unifor.br/handle/tede/88221.

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Made available in DSpace on 2019-03-29T23:27:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-27
Transport of goods has represented an important role in economic development throughout the history and ship containerization brought great advantages. Its invention in mid-1950s brought down the cost of transport and reduced time for loading and unloading cargo. Consequently, it increased efficiency of port working and reduced handling cargo to hours instead of weeks, as before. However, the good use of containerization involves new and specialized logistic process, a number of technologies and automated systems to handle a great number of containers and even greater volume of cargo. To answer these requirements, computation appears as important tool. The described scenary has been treated in academic literature as the Container Loading Problem (CLP), with some variants. It is necessary consider practical requirements, for example the stability of cargo or weight distribution. The last one is of vital importance since the position of the centre of gravity of cargo affects the stability during its transport. When desconsidered, it could result in damage to cargo or vehicle. During our research, we were specially interested in this requirement. But, in order compare the found solutions with other ones, we proposed a methodology to measures the weight distribution. So, to the described problem, specifically the Knapsack Loading Problem (3D-KLP), this work presents a methodology that not only maximizes the packed cargo volume but also optimizes the weight distribution, its great contribution. Mainly if we consider that the cargo to be packed is composed by items with different densities, which turns the problem more difficult. The present methodology is composed by two phases with distinct goals. The first phase is concerned with maximize the weight distribution combining a search algorithm, the backtracking, with heuristics that solve integer linear programming models. The second phase executes a Genetic Algorithm to maximize the weight distribution of previously packed cargo. We also present a justification for why genetic algorithm was used in our methodology. An additional application was made to solve cutting problems. This class of problems occurs in various industrial process, when it is necessary to cut different types of material as glass, wood or parper, with a minimum of waste. We use a well-known benchmark test to compare our results with other approaches. This work also presents a case study of our implementation using some real data in a factory of stoves and refrigerators in Brazil. It shown promising results in reduced time. Keywords: Container Loading Problem, Knapsack Loading Problem, Weight Distribution, Integer Programming, Backtracking, Genetic Algorithms.
O transporte de carga tem representado um papel fundamental no desenvolvimento econômico no decorrer da história e a conteinerização trouxe grandes vantagens. Seu advento reduziu os custos de transporte bem como o tempo de carga. Portanto, aumentou a eficiência do trabalho em portos e reduziu o tempo necessário para operações com carga para horas, ao invés de semanas como anteriormente. Contudo, o bom uso dos contêineres involve novos e especializados processos logísticos, uma grande quantidade de tecnologias além de sistemas automatizados para manipular uma elevada quantidade de contêineres e ainda maior volume de carga. Para atender a estes requisitos, computação aparece como uma importante ferramenta. O cenário descrito tem sido tratado na literatura acadêmica como o Problema de Carregamento de Contêiner (CLP, do inglês Container Loading Problem), com algumas variantes. é também necessário considerar requisitos práticos como, por exemplo, a estabilidade da carga ou distribuição do peso. Este último de vital importância uma vez que o centro de gravidade da carga afeta a estabilidade durante seu transporte. Se descosiderado, pode-se danificar tanto a carga como o veículo. Durante nossa pesquisa, nós estivemos especialmente interessados neste requisito. E a fim de comparar a qualidade dos resultados obtidos, propusemos uma maneira de mensurar a distribuição do peso. Portanto, dado o problema descrito, especificamente o 3D Knapsack Loading Problem, este trabalho apresenta um algoritmo que não apenas maximiza o volume total carregado mas também otimiza a distribuição do peso da carga, sua grande contribuição. Principalmente se considerarmos que a carga é composta de itens com diferentes valores de densidade, o que torna o problema ainda mais difícil. A metodologia consiste em duas fases com objetivos diferentes. A primeira fase ocupa-se em maximizar o volume carregado por combinar um algoritmo de busca, o backtracking, com heurísticas que resolvem modelos de programação linear inteira. A segunda fase executa um algoritmo genético para maximizar a distribuição do peso da carga previamente colocada. Apresentamos também uma justificativa do porque algoritmo genéticos foram usados em nossa metodologia. Uma aplicação adicional foi feita para resolver problemas de corte. Esta classe de problemas ocorre em vários processos industriais, quando é necessário cortar diferentes tipos de materiais, como vidro, madeira ou papel, com um mínimo de desperdício. A fim de comparação, usamos bibliotecas de teste bem conhecidas na literatura e um estudo de caso usando informações reais de uma fábrica de fogões e geladeiras no Brasil. São apresentados resultados promissores alcançados em tempo reduzido. Palavras-chave: Problema de Carregamento de Contêiner, Knapsack Loading Problem, Distribuição do Peso, Programação Linear Inteira, Backtracking, Algoritmos Genéticos.
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Anagnostou, Anastasia. "A distributed simulation methodology for large-scale hybrid modelling and simulation of emergency medical services." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/11218.

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Healthcare systems are traditionally characterised by complexity and heterogeneity. With the continuous increase in size and shrinkage of available resources, the healthcare sector faces the challenge of delivering high quality services with fewer resources. Healthcare organisations cannot be seen in isolation since the services of one such affects the performance of other healthcare organisations. Efficient management and forward planning, not only locally but rather across the whole system, could support healthcare sector to overcome the challenges. An example of closely interwoven organisations within the healthcare sector is the emergency medical services (EMS). EMS operate in a region and usually consist of one ambulance service and the available accident and emergency (A&E) departments within the coverage area. EMS provide, mainly, pre-hospital treatment and transport to the appropriate A&E units. The life-critical nature of EMS demands continuous systems improvement practices. Modelling and Simulation (M&S) has been used to analyse either the ambulance services or the A&E departments. However, the size and complexity of EMS systems constitute the conventional M&S techniques inadequate to model the system as a whole. This research adopts the approach of distributed simulation to model all the EMS components as individual and composable simulations that are able to run as standalone simulation, as well as federates in a distributed simulation (DS) model. Moreover, the hybrid approach connects agent-based simulation (ABS) and discrete event simulation (DES) models in order to accommodate the heterogeneity of the EMS components. The proposed FIELDS Framework for Integrated EMS Large-scale Distributed Simulation supports the re-use of existing, heterogeneous models that can be linked with the High Level Architecture (HLA) protocol for distributed simulation in order to compose large-scale simulation models. Based on FIELDS, a prototype ABS-DES distributed simulation EMS model was developed based on the London EMS. Experiments were conducted with the model and the system was tested in terms of performance and scalability measures to assess the feasibility of the proposed approach. The yielded results indicate that it is feasible to develop hybrid DS models of EMS that enables holistic analysis of the system and support model re-use. The main contributions of this thesis is a distributed simulation methodology that derived along the process of conducting this project, the FIELDS framework for hybrid EMS distributed simulation studies that support re-use of existing simulation models, and a prototype distributed simulation model that can be potentially used as a tool for EMS analysis and improvement.
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Garmendia, Daniel Charles. "A multi-disciplinary conceptual design methodology for assessing control authority on a hybrid wing body configuration." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54328.

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The primary research objective was to develop a methodology to support conceptual design of the Hybrid Wing Body (HWB) configuration. The absence of a horizontal tail imposes new stability and control requirements on the planform, and therefore requiring greater emphasis on control authority assessment than is typical for conceptual design. This required investigations into three primary areas of research. The first was to develop a method for designing an appropriate amount of redundancy. This was motivated widely varying numbers of trailing edge elevons in the HWB literature, and inadequate explanations for these early design decisions. The method identifies stakeholders, metrics of interest, and synthesizes these metrics using the Breguet range equation for system level comparison of control surface layouts. The second area of research was the development trim analysis methods that could accommodate redundant control surfaces, for which conventional methods performed poorly. A new measure of control authority was developed for vehicles with redundant controls. This is accomplished using concepts from the control allocation literature such as the attainable moment subset and the direct allocation method. The result is a continuous measure of remaining control authority suitable for use during HWB sizing and optimization. The final research area integrated performance and control authority to create a HWB sizing environment, and investigations into how to use it for design space exploration and vehicle optimization complete the methodology. The Monte Carlo Simulation method is used to map the design space, identify good designs for optimization, and to develop design heuristics. Finally, HWB optimization experiments were performed to discover best practices for conceptual design.
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Roy, Hillol K. "A generalised powertrain component size optimisation methodology to reduce fuel economy variability in hybrid electric vehicles." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/62732/.

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Although hybrid electric vehicles (HEVs) generally improve fuel economy (FE) compared to conventional vehicles, evidence of higher FE variability in HEVs compared to conventional vehicles indicates that apart from the improvement in FE, the reduction of FE variability is also of significant importance for HEVs. Over the years research on how to optimise powertrain component sizes of HEVs has generally focused on improving FE over a given driving pattern; FE variability over a realistic range of driving patterns has generally been overlooked, and this can lead to FE benefits of HEVs not being fully realised in real-world usage. How to reduce the FE variability in HEVs due to variation in driving patterns through the optimisation of powertrain component sizes is considered as the research question. This research proposes a new methodology in which powertrain components are optimised over a range of driving patterns representing different traffic conditions and driving styles simultaneously. This improves upon the traditional methodology followed in the reviewed literature, where an optimisation is performed for each individual driving pattern. An analysis shows that the traditional methodology could produce around 20% FE variability due to variation in driving patterns. This study considers a computer simulation model of a series-parallel Toyota Prius HEV for the investigation. Four powertrain components, namely, internal combustion engine, generator, motor, and battery of the Toyota Prius are optimised for FE using a genetic algorithm. For both the proposed and traditional methodologies, the powertrain components are optimised based on 5 standard driving patterns representing different traffic conditions and driving styles. During the optimisation, the proposed methodology considers all the 5 driving patterns simultaneously, whereas the traditional methodology considers each driving pattern separately. The optimum designs of both the methodologies and the simulation model of the Toyota Prius which is the benchmark vehicle for this study are evaluated for FE over the aforementioned 5 standard driving patterns and also 10 real-world driving patterns of a predefined route consisting of urban and highway driving patterns. The proposed methodology provides a single optimum design over the 5 standard driving patterns, whereas the traditional methodology provides 5 different optimum designs, one for each driving pattern. The single optimum design produced by the proposed methodology is independent of the sequence of driving patterns. The proposed methodology reduces FE variability by 5.3% and up to 48.9% with comparable average FE compared to the Toyota Prius and traditional methodology, respectively over the 10 real-world driving patterns, whereas none of the optimum designs of the traditional methodology is able to reduce FE variability compared to the Toyota Prius. This research provides a promising direction to address customer concerns related to FE in the real-world and improves understanding of the effect of driving patterns on the design of powertrain components.
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Brennen, Peter Alexander. "SIMULATION OF AN OXIDIZER-COOLED HYBRID ROCKET THROAT: METHODOLOGY VALIDATION FOR DESIGN OF A COOLED AEROSPIKE NOZZLE." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/166.

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A study was undertaken to create a finite element model of a cooled throat converging/diverging rocket nozzle to be used as a tool in designing a cooled aerospike nozzle. Using ABAQUS, a simplified 2D axisymmetric model was created featuring only the copper throat and stainless steel support ring, which were brazed together for the experimental test firings. This analysis was a sequentially coupled thermal/mechanical model. The steady state thermal data matched closely to experimental data. The subsequent mechanical model predicted a life of over 300 cycles using the Manson-Halford fatigue life criteria. A mesh convergence study was performed to establish solution mesh independence. This model was expanded by adding the remainder of the parts of the nozzle aft of the rocket motor so as to attempt to match the transient nature of the experimental data. This model included variable hot gas side coefficients in the nozzle calculated using the Bartz coefficients and mapped onto the surface of the model using a FORTRAN subroutine. Additionally, contact resistances were accounted for between the additional parts. The results from the preliminary run suggested the need for a parameter re-evaluation for cold side gas conditions. Parametric studies were performed on contact resistance and cold side film coefficient. This data led to the final thermal contact conductance of k=0.005 BTU/s•in.•°R for contact between metals, k=0.001 BTU/s•in.•°R for contact between graphite and metal, and h=0.03235 BTU/s2•in.•°R for the cold side film coefficient. The transient curves matched closely and the results were judged acceptable. Finally, a 3D sector model was created using identical parameters as the 2D model except that a variable cold side film condition was added. Instead of modeling a symmetric one or two inlet/one or two outlet cooling channel, this modeled a one inlet/one outlet nozzle in which the coolant traveled almost the full 360° around the cooling annulus. To simplify the initial simulation, the model was cut at the barrier between inlet and outlet to form one large sector, rather than account for thermal gradients across this barrier. This simplified nozzle produced expected data, and a 3D full nozzle model was created. The cold side film coefficients were calculated from previous experimental data using a simplified 2D finite difference approach. The full nozzle model was created in the same manner as the 2D full nozzle model. A mesh convergence study was performed to establish solution mesh independence. The 3D model results matched well to experimental data, and the model was considered a useful tool for the design of an oxidizer cooled aerospike nozzle.
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Bakare, Adeyinka A. "A Methodology for Cyberthreat ranking: Incorporating the NIST Cybersecurity Framework into FAIR Model." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1583247043269043.

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Na, Wei. "Frequency Domain Linearized Navier-Stokes Equations Methodology for Aero-Acoustic and Thermoacoustic Simulations." Licentiate thesis, KTH, Aeroakustik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-179677.

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The first part of the thesis focuses on developing a numerical methodology to simulate the acoustic properties of a hybrid liner consisting of a perforated plate, a porous layer and a Helmholtz cavity. Liners are always a standard way to reduce noise in today’s aeroengines, e.g. the fan noise can be reduced effectively through the installation of acoustic liners as wall treatments in the ducts. In order to optimize a liner in the design phase, an accurate and efficient prediction tool is of interests. Hence, a unified Linearized Navier-Stokes equations(LNSE) approach has been implemented in the thesis, combining the LNSE in frequency domain with the fluid equivalent model. The LNSE is applied in the vicinity of the perforated plate to simulate sound propagation including viscous damping effect, and the fluid equivalent model is used to model the sound propagation in the porous material including absorption. The second part of the thesis focuses on the prediction of thermoacoustic instabilities. Thermoacoustic instabilities arise when positive coupling occurs between the flame and the acoustics in the feedback loop, i.e. the flame acts as an amplifier of the disturbances (acoustic or fluid) at a natural frequency of the combustion system. Once the thermoacoustic instabilities occur, it will lead to extremely high noise levels within a relatively narrow frequency range, resulting in a huge damage to the structure of the combustors. Hence, a solution must be found, which breaks the link between the combustion process and the structural acoustics. The numerical prediction of thermoacoustic instabilities in the thesis is performed by two different numerical methodologies. One solves the Helmholtz equation in combination of the flame n − tau model with the low Mach number assumptions, and the other solves the Linearized Navier-Stokes equations in frequency domain with mean flow. The result show that the mean flow has a significant effect on the thermoacoustic instabilities, which is non-negligible when the Mach number reaches to 0.15.

QC 20151221


TANGO
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NASCIMENTO, WALLACE JOSE DAMASCENO DO. "THERMAL POWER PORTFOLIO VALUATION UNDER UNCERTAINTY: A HYBRID METHODOLOGY USING FUZZY NUMBERS, REAL OPTIONS AND OPTIMIZATION BY GENETIC ALGORITHMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=30498@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
FUNDAÇÃO DE APOIO À ESCOLA TÉCNICA
PROGRAMA DE EXCELENCIA ACADEMICA
Os grandes agentes do mercado de energia dedicam muitos esforços na avaliação e decisão da alocação ótima de capital para a implementação de projetos, em decorrência do grande número de projetos candidatos em seus portfólios de investimentos. Essas decisões visam escolher o subconjunto de projetos a ser implementado, pois os recursos orçamentários são geralmente menores que o necessário para a implementação de todos eles. Muitos são os riscos apresentados, e quanto mais riscos e incertezas, maiores se tornam as dificuldades de avaliação e decisões de investimento de maneira otimizada. As metodologias clássicas para avaliação de portfólios de projetos de investimento são baseadas em maximizar os retornos (VPL, TIR, etc) e minimizar o risco (desvio-padrão do VPL, variância, etc). Muitas vezes, estes métodos tradicionais de avaliação podem não conseguir tratar adequadamente as flexibilidades gerenciais (Opções Reais) características dos projetos, assim como os riscos e incertezas, devido às possíveis dificuldades de solução e modelagem matemática (multi-variáveis) dos problemas. O desenvolvimento e aplicação de modelos alternativos, tais como os baseados na Teoria de Opções Reais, inclusive com a utilização de métodos de Inteligência Computacional, podem se mostrar mais adequados para estes problemas. Nesta tese é desenvolvida uma metodologia híbrida, apresentando um modelo de Opções Reais Fuzzy para a avaliação de projetos de Revamp por um agente do mercado de Geração Termelétrica de Energia, a partir de um Portfólio de Opções Reais em ambiente de incertezas. Para a seleção do subconjunto de projetos por faixa orçamentária, é aplicado um Algoritmo Genético para otimização multi-critério, através da utilização de um índice de ponderação retorno x risco (lâmbda).
Large players in energy market dedicate many efforts in valuation and optimal capital allocation decision for their project implementation, due the large candidate projects number in their investment portfolios. These decisions aim to choose the projects subset to be implemented, because the monetary resources are generally smaller than necessary for all projects implementation. There are many risks, and with risks and uncertainties, greater become the difficulties in analysis and optimally investment decisions. The classical methods to investment portfolios are based on to maximize returns (NPV, IRR, among others) and to minimize risks (NPV standard deviation, variance, among others). Often, these traditional methods may not be able to handle properly the projects managerial flexibilities (Real Options), as well the risks and uncertainties, due to possible solution difficulties and mathematical modeling problems (multi variables). Alternative models development and implementation, such as those based on Real Options Theory, including the use of Computational Intelligence methods, may be more suitable for these problems. In this thesis, a hybrid methodology is developed, presenting a Fuzzy Real Options model for Revamp projects valuation by a Thermoelectric Power Generation market player, from a Real Options Portfolio in uncertainties environment. For selecting the projects subset by budget range, a multi-criteria Genetic Algorithm optimization is applied, using a weighting return x risk index (lambda).
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37

Morton, Sarah. "Establishing a hybrid-methodology model for co-designing behaviour change : within the context of adventure sport participation in Scotland." Thesis, Abertay University, 2016. https://rke.abertay.ac.uk/en/studentTheses/5d019691-4369-422f-a485-cc69b96d0b8e.

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Adventure sport participation numbers have significantly increased over the period of the past ten years; it has been suggested that the emergence of an experience economy, where experiences have more value than possessions, could be a key factor for this increase. Motivations for taking part in an adventure sport activity varies between participants, and perhaps even more so than those motivations that were expressed by participants’ pre-experience economy. There are a number of theories about increased participant numbers; for example, the type of demographic, how they approach participation, and approximate suggestions of how the trend for experiences rather than possessions will evolve in the future. However, there is little that explores the experiences of these newer participants, how they behave, and how they are being received by the adventure sport industry. Additionally, there is no evidence to suggest a definite understanding of the needs and requirements of these participants, nor has an investigation been conducted to measure how well the industry is meeting these. Likewise, the potential to adapt existing provision, to expose untapped opportunities, appears unconsidered, and therefore may have benefit for both providers and participants. This study took its lead from using a process of problematization, whereby the problem is explored, identified and defined by the designer(s), rather than presented to them to solve. Using this approach, a hybrid methodologies model was designed and tested to explore the perceptions and experiences of adventure sport participants, to identify any changes that may be occurring as a result of the experience economy and increased numbers of participants taking up an adventure sport activity. Immersive ethnographic and qualitative methods were implemented to better understand identified changes and issues, and quantitative methods were used to elaborate on, confirm and validate the findings. By doing this it was also possible to establish the efficacy of taking a lived experience approach to identifying and exploring emergent and currently unaddressed issues. The study identified three key themes of interest to adventure sport participants: provision of information, ability to accurately assess skill level and participate safely, and being a part of the adventure sport community. These emerging themes were problematizated, validated, and a process of co-design and ideation was used to establish and suggest a solution that could be implemented by the industry to solve the identified issues. This study highlights the potential of using lived experiences to identify a problem, and employs new mixed methodologies to develop a better understanding of critical factors occurring within a specific industry and its associated communities. The study uses this knowledge to generate a designed solution. The theories and methods discussed by the study have transferable values, and could be used within a wide range of other subject areas, being especially useful when a hypothesis proves difficult to identify and define at the outset of a study.
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38

Hellström, Douglas. "Uncertainty management – How to handle project uncertainty : A case study at Rimaster Development." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299782.

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We know that it is difficult to forecast the future, and the same applies to project management. There are a lot of occurrences that are both predictable and not possible throughout the course of a project. The management of uncertainty is a management method that helps to forecast and adjust to future occurrences. In this context, frameworks and tools have been created to help project managers genuinely understand a project's potential.  The study was conducted as a case study at Rimaster Development in Söderhamn and aimed at discovering sources of uncertainty within their project development that affect project performance. The study is built on both quantitative and qualitative data gathering from a workshop, survey, meetings, and interviews from ten different projects of Rimaster. The study had five respondents who contributed with two projects, each of which they had been a part of previously, one classified as uncertain and one as more certain.  The data were analyzed with the statistics tool SPSS, where variables were computed based on the empirical findings in the uncertainty survey. The result was then presented through uncertainty attribute matrices to identify how each project performed in relation to customer satisfaction as well as time plan and budget. Here, dependent variables were tested, such as if the uncertainty score (the higher value, the more uncertain is the project) influenced project performance. From the data, two categories of projects could be developed: Higher performing projects and lower performing projects. To this, significant analysis of the performance groups was performed to find parameters that were significantly different between the categories. To capture more data to the thesis, each project was then evaluated through an individual project analysis which consisted of analyzing the data from the survey more closely for each project. The findings from this were then supported with qualitative interviews.  The findings in the study suggest that there is a relationship between project uncertainty and lower-performing projects in relationship to time plan and budget. Further, sixteen uncertainty parameters showed to have a significant value in the comparison between higher and lower performing projects. Based upon the data and the analysis of the study, managerial recommendations have been provided to Rimaster on tools and development processes that may assist the organization's uncertainty management and increase their project performance.
Det är allmänt känt att det är omöjligt att tydligt förutsäga framtiden och detsamma gäller projektledning. Det finns många händelser som är både oförutsägbara och riskfyllda under ett projektets gång, där osäkerhetshanteringen är en hanteringsmetod som hjälper till att prognostisera och anpassa sig till framtida händelser. Tidigare forskning inom osäkerhetshantering har utvecklat ramar och verktyg för att hjälpa projektledare att verkligen förstå ett projekts potential.  Studien genomfördes som en fallstudie vid Rimaster Development i Söderhamn och syftade till att upptäcka källor till osäkerhet inom deras utvecklingsavdelning som påverkar projektets prestanda. Studien bygger på både kvantitativ och kvalitativ datainsamling från en workshop, enkätundersökning, möten och intervjuer från tio olika projekt från Rimaster. Studien enkätundersökning hade fem svarande som bidrog med två projekt som de tidigare hade varit en del av, ett klassificerat som osäkert och ett som mer säkert.  Data erhållen from enkäten analyserades med statistikverktyget SPSS där variabler beräknades baserat på empiriska resultat i osäkerhetsundersökningen. Resultatet presenterades sedan genom osäkerhetsattributmatriser för att identifiera hur varje projekt presterade i förhållande till kundnöjdhet samt tidsplan och budget. Här testades beroende variabler som om den osäkerhetspoängen varde projekt erhöll (ju högre värde, desto mer osäkert är projektet) hade en effekt på projektets prestanda. Från analysen kunde två kategorier av projekt utvecklas: projekt med högre prestanda och projekt med lägre prestanda. Utöver detta genomfördes en signifikansanalys av prestationsgrupperna för att hitta parametrar som var signifikanta olika mellan kategorierna. För att samla ytterliga data till avhandlingen utvärderades varje projekt genom en individuell projektanalys som bestod av att analysera data från undersökningen närmare för varje projekt. Resultaten från detta styrktes sedan med kvalitativa intervjuer.  Resultaten i studien antyder att det finns ett samband mellan projektosäkerhet och projekt med lägre resultat i förhållande till tidsplan och budget. Vidare visade sig sexton osäkerhetsparametrar ha ett signifikant värde i jämförelsen mellan projekt med högre och lägre resultat. Baserat på analyseringen av den data studien samlat in så har rekommendationer överlämnats till Rimaster om verktyg och utvecklingsprocesser som kan hjälpa organisationens osäkerhetshantering och därmed öka deras projektprestanda.
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39

Basso, Eduardo Donadel. "Avaliação do potencial econômico na padronização de projetos navais." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/127913.

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A padronização figura como uma alternativa importante para a indústria, trazendo redução de custos, aumento de produtividade e de qualidade dos processos e produtos gerados. No setor naval da Bacia do Sudeste, ela apresenta-se de forma mais tímida, uma vez que o volume de embarcações produzidas é muito menor se comparado a indústrias de massa. O presente trabalho apresenta um estudo sobre a padronização na indústria, demonstrando definições importantes relacionadas ao tema, bem como a apresentação de metodologias para a padronização de produtos e processos. De forma a gerar subsídios para a avaliação estrutural de projetos navais, são propostas duas diferentes metodologias, a primeira de cunho naval, proveniente da literatura técnica da área, e a segunda híbrida, baseada em uma norma para estruturas metálicas, que é validada através de uma análise não linear em elementos finitos. É realizado também um estudo preliminar visando desenvolver uma avaliação econômica, que considere diversos custos de fabricação e operação de uma embarcação, bem como contempla os benefícios da padronização. As metodologias mencionadas são utilizadas em três diferentes aplicações, aonde são propostas diversas configurações para o projeto de um painel básico de uma embarcação real, e os resultados destas análises são comparados ao projeto original, dando subsídios para uma avaliação preliminar da viabilidade econômica da padronização. Os dados gerados nestas análises são utilizados como parâmetros de entrada de um algoritmo de ajuste de leis potenciais chamado SLAW®, aos quais são capazes de prever o custo de determinada configuração através do cálculo de alguns parâmetros do projeto, permitindo identificar quais parâmetros são mais importantes na definição do custo do objeto em estudo. Ao final tem-se uma discussão dos resultados obtidos através das ferramentas mencionadas, visando avaliar a importância da padronização no custo da embarcação.
Standardization figure as an important alternative for the industry, bringing cost savings, increased productivity and quality of processes and products generated. In the naval sector of the Southeast Basin, it presents more timid, since the volume of produced vessels is much lower coMPared to mass industries. This paper presents a study on standardization in the industry, demonstrating important definitions related to the topic, and the presentation of methodologies for the standardization of products and processes. In order to generate subsidies for the structural evaluation, of naval projects, two different methods are proposed, the first hybrid, based on a standard for steel structures, which is validated through a nonlinear finite element analysis, and the second from naval sector, belonging to the technical literature. There are also proposed the basis for a methodology for the economic evaluation, which considers various manufacturing and operating costs of a vessel and includes the benefits of standardization. The methods mentioned are used in three different applications, where several settings for a basic panel design of a real vessel are proposed, the results of these analysis are compared to the original design, giving data for the evaluation of the economic viability of standardization. The data generated in these analysis are used as input parameters of a potential laws adjustment algorithm called SLAW®, these laws are able to predict the cost of a specific configuration by calculating some design parameters, allowing to identify which parameters are most important the definition of the cost of the object under study. At the end it presents a discussion of the results obtained through the mentioned tools, to evaluate the importance of standardization in the cost of the vessel.
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40

Bolletta, Alberto. "Design of alternative energy storage systems for hybrid vehicles based on statistical processing of driving cycles information." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2092/.

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Hybrid vehicles represent the future for automakers, since they allow to improve the fuel economy and to reduce the pollutant emissions. A key component of the hybrid powertrain is the Energy Storage System, that determines the ability of the vehicle to store and reuse energy. Though electrified Energy Storage Systems (ESS), based on batteries and ultracapacitors, are a proven technology, Alternative Energy Storage Systems (AESS), based on mechanical, hydraulic and pneumatic devices, are gaining interest because they give the possibility of realizing low-cost mild-hybrid vehicles. Currently, most literature of design methodologies focuses on electric ESS, which are not suitable for AESS design. In this contest, The Ohio State University has developed an Alternative Energy Storage System design methodology. This work focuses on the development of driving cycle analysis methodology that is a key component of Alternative Energy Storage System design procedure. The proposed methodology is based on a statistical approach to analyzing driving schedules that represent the vehicle typical use. Driving data are broken up into power events sequence, namely traction and braking events, and for each of them, energy-related and dynamic metrics are calculated. By means of a clustering process and statistical synthesis methods, statistically-relevant metrics are determined. These metrics define cycle representative braking events. By using these events as inputs for the Alternative Energy Storage System design methodology, different system designs are obtained. Each of them is characterized by attributes, namely system volume and weight. In the last part the work, the designs are evaluated in simulation by introducing and calculating a metric related to the energy conversion efficiency. Finally, the designs are compared accounting for attributes and efficiency values. In order to automate the driving data extraction and synthesis process, a specific script Matlab based has been developed. Results show that the driving cycle analysis methodology, based on the statistical approach, allows to extract and synthesize cycle representative data. The designs based on cycle statistically-relevant metrics are properly sized and have satisfying efficiency values with respect to the expectations. An exception is the design based on the cycle worst-case scenario, corresponding to same approach adopted by the conventional electric ESS design methodologies. In this case, a heavy system with poor efficiency is produced. The proposed new methodology seems to be a valid and consistent support for Alternative Energy Storage System design.
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41

Assaye, Abb. "Torsional Stiffness Calculation of CFRP Hybrid Chassis using Finite Element Method : Development of calculation methodology of Formula Student CFRP Chassis." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-79065.

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Composite sandwich structures are being used in the automotive and aerospace industries at an increasing rate due to their high strength and stiffness per unit weight.  Many teams in the world’s largest engineering competition for students, Formula Student, have embraced these types of structures and are using them in their chassis with the intent of increasing the torsional stiffness per unit weight.   The Formula Student team at Karlstad University, Clear River Racing, has since 2017 successfully built three carbon fiber based sandwich structure chassis. A big challenge when designing this type of chassis is the lack of strategy regarding torsional stiffness simulations. Thus, the goal of this thesis project was to provide the organization with a set of accurate yet relatively simple methods of modelling and simulating the torsional stiffness of the chassis.   The first step in achieving the goal of the thesis was the implementation of simplifications to the material model. These simplifications were mainly targeted towards the aluminum honeycomb core. In order to cut computational times and reduce complexity, a continuum model with orthotropic material properties was used instead of the intricate cellular structure of the core. To validate the accuracy of this simplification, the in-plane elastic modulus of the core was simulated in the finite element software Abaqus. The stiffness obtained through simulations was 0.44 % larger than the theoretical value. The conclusion was therefore made that the orthotropic continuum model was an accurate and effective representation of the core.   Furthermore, simplifications regarding the adhesive film in the core-carbon fiber interfaces were made by using constraints in Abaqus instead of modelling the adhesive films as individual parts. To validate this simplification and the overall material model for the sandwich structure, a three-point bend test was simulated in Abaqus and conducted physically. The stiffness for the sandwich panel obtained through physical testing was 2.4 % larger than the simulated stiffness. The conclusion was made that the simplifications in the material modelling did not affect the accuracy in a significant way.   Finally, the torsional stiffness of the 2020 CFRP chassis was found to be 12409.75 Nm/degree.   In addition to evaluating previously mentioned simplifications, this thesis also serves as a comprehensive guide on how the modelling of the chassis and how the three-point bend test can take place in regards to boundary conditions, coordinate system assignments and layup definitions.
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42

Kong, Suyao. "Advanced passivity-based control for hybrid power systems : application to hybrid electric vehicles and microgrids." Thesis, Bourgogne Franche-Comté, 2020. http://indexation.univ-fcomte.fr/nuxeo/site/esupversions/a01b06c5-fb6c-452d-bd16-02b269cd0bb9.

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Un système hybride à base de pile à combustible (PàC) est une solution efficace pour faire face aux problèmes de pollution atmosphérique et de pénurie des combustibles fossiles. Cette thèse se concentre sur la conception de la commande pour les systèmes d'alimentation hybrides à base de PàC, et appliquée à deux applications : le véhicule électrique et le centre de données alimenté par un micro-réseau.Tout d'abord, cette thèse propose une commande basée sur la passivité pour un système hybride PàC/supercondensateurs (SCs). Cette commande a été conçue via la méthode de conception IDA-PBC (Interconnection and Damping Assignment - Passivity Based Control), afin de résoudre le problème de coordination des convertisseurs. L'état de charge des SCs ainsi que toutes les limitations sont intégrés directement dans la loi de commande. Un banc d'essais PHIL (Power Hardware-in-the-loop) est utilisé pour la validation. Ensuite, un filtre de Kalman étendu (EKF) est combiné avec la commande proposée, pour prévoir l'état de santé (SoH) de la pile à combustible. Enfin, un banc d'essais HIL (Hardware-in-the-loop) basé sur un FPGA INTEL / ALTERA est conçu afin de valider le fonctionnement des algorithmes en temps réel pour un véhicule commercial.Pour l'application à un micro-réseau, une commande passive est proposée pour un système hybride comprenant des panneaux photovoltaïques, une PàC, des SCs et un électrolyseur. La faisabilité de cette commande est validée par les résultats expérimentaux sur un banc d'essai PHIL. Ce travail est intégré au projet ANR DATAZERO.La nouveauté principale de cette commande est qu'elle intègre certaines contraintes de composants directement dans la loi de commande, en préservant la stabilité de l’ensemble du système, en boucle fermée
A Fuel cell (FC) hybrid power system is a promising solution to deal with the atmospheric pollution and fossil fuels shortage problems. This thesis focuses on the controller design for FC hybrid power systems, towards two applications: the hybrid electrical vehicle and the microgrid-powered datacenter.Firstly, this thesis proposes an advanced passivity-based control for a FC/super-capacitors (SCs) hybrid system. In order to solve the converters coordination problem, a controller designed using the design method Interconnection and Damping Assignment - Passivity-Based Control (IDA-PBC) is applied, which considers the state-of-charge of the SCs as well as voltage and current limitations. The proposed controller is validated on a Power Hardware-in-the-loop (PHIL) platform. Then an Extended Kalman Filter (EKF) is applied to forecast the State-of-Health (SoH) of the fuel cell and is combined with the proposed controller. Finally, a Hardware-in-the-loop (HIL) platform based on an INTEL/ALTERA FPGA is designed in order to validate the real-time operation of the algorithms for a specific case study with a commercial vehicle.For microgrid applications, a passivity-based controller for a hybrid power supply system for a green datacenter is proposed, including photovoltaic panels, a fuel cell, SCs and an electrolyzer. The feasibility of this non-linear controller is proven by the simulation results and experimental validation on a PHIL test bench. This work is integrated into the ANR DATAZERO project.The main novelty of the proposed controller is that it integrates some component constraints directly into the controller equations, while the locally asymptotic stability of the whole closed-loop system is preserved
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43

Santos, Rodríguez Cristian de. "Backanalysis methodology based on multiple optimization techniques for geotechnical problems." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/334179.

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Nowadays, thanks to the increase of computers capability to solve huge and complex problems, and also thanks to the endless effort of the geotechnical community to define better and more sophisticated constitutive models, the challenge to predict and simulate soil behavior has been eased. However, due to the increase in that sophistication, the number of parameters that define the problem has also increased. Moreover, frequently, some of those parameters do not have a real geotechnical meaning as they just come from mathematical expressions, which makes them difficult to identify. As a consequence, more effort has to be placed on parameters identification in order to fully define the problem. This thesis aims to provide a methodology to facilitate the identification of parameters of soil constitutive models by backanalysis. The best parameters are defines as those that minimize an objective function based on the differences between measurements and computed values. Different optimization techniques have been used in this study, from the most traditional ones, such as the gradient based methods, to the newest ones, such as adaptive genetic algorithms and hybrid methods. From this study, several recommendations have been put forward in order to take the most advantage of each type of optimization technique. Along with that, an extensive analysis has been carried out to determine the influence on soil parameters identification of what to measure, where to measure and when to measure in the context of tunneling. The Finite Element code Plaxis has been used as a tool for the direct analysis. A FORTRAN code has been developed to automate the entire backanalysis procedure. The Hardening Soil Model (HSM) has been adopted to simulate the soil behavior. Several soil parameters of the HSM implemented in Plaxis, such as E_50^ref, E_ur^ref, c and f, have been identified for different geotechnical scenarios. First, a synthetic tunnel case study has been used to analyze all the different approaches that have been proposed in this thesis. Then, two complex real cases of a tunnel construction (Barcelona Metro Line 9) and a large excavation (Girona High-Speed Railway Station) have been presented to illustrate the potential of the methodology. Special focus on the influence of construction procedures and instruments error structure has been placed for the tunnel backanalysis, whereas in the station backanalysis, more effort has been devoted to the potential of the concept of adaptive design by backanalysis. Moreover, another real case, involving a less conventional geotechnical problem, such as Mars surface exploratory rovers, has been also presented to test the backanalysis methodology and the reliability of the Wong & Reece wheel-terrain model; widely adopted by the terramechanics community, but nonetheless, still not fully accepted when analyzing lightweight rovers as the ones that have been used in recent Mars exploratory missions.
Actualmente, gracias al aumento de la capacidad de los ordenadores para resolver problemas grandes y complejos, y gracias también al gran esfuerzo de la comunidad geotécnica de definir mejores y más sofisticados modelos constitutivos, se ha abordado el reto de predecir y simular el comportamiento del terreno. Sin embargo, debido al aumento de esa sofisticación, también ha aumentado el número de parámetros que definen el problema. Además, frecuentemente, muchos de esos parámetros no tienen un sentido geotécnico real dado que vienen directamente de expresiones puramente matemáticas, lo cual dificulta su identificación. Como consecuencia, es necesario un mayor esfuerzo en la identificación de los parámetros para poder definir apropiadamente el problema. Esta tesis pretende proporcionar una metodología que facilite la identificación mediante el análisis inverso de los parámetros de modelos constitutivos del terreno. Los mejores parámetros se definen como aquellos que minimizan una función objetivo basada en la diferencia entre medidas y valores calculados. Diferentes técnicas de optimización han sido utilizadas en este estudio, desde las más tradicionales, como los métodos basados en el gradiente, hasta las más modernas, como los algoritmos genéticos adaptativos y los métodos híbridos. De este estudio, se han extraído varias recomendaciones para sacar el mayor provecho de cada una de las técnicas de optimización. Además, se ha llevado a cabo un análisis extensivo para determinar la influencia sobre qué medir, dónde medir y cuándo medir en el contexto de la excavación de un túnel. El código de Elementos Finitos Plaxis ha sido utilizado como herramienta de cálculo del problema directo. El desarrollo de un código FORTRAN ha sido necesario para automatizar todo el procedimiento de Análisis Inverso. El modelo constitutivo de Hardening Soil ha sido adoptado para simular el comportamiento del terreno. Varios parámetros del modelo constitutivo de Hardening implementado en Plaxis, como E_50^ref, E_ur^ref, c y f, han sido identificados para diferentes escenarios geotécnicos. Primero, se ha utilizado un caso sintético de un túnel donde se han analizado todas las distintas técnicas que han sido propuestas en esta tesis. Después, dos casos reales complejos de una construcción de un túnel (Línea 9 del Metro de Barcelona) y una gran excavación (Estación de Girona del Tren de Alta Velocidad) se han presentado para ilustrar el potencial de la metodología. Un enfoque especial en la influencia del procedimiento constructivo y la estructura del error de las medidas se le ha dado al análisis inverso del túnel, mientras que en el análisis inverso de la estación el esfuerzo se ha centrado más en el concepto del diseño adaptativo mediante el análisis inverso. Además, otro caso real, algo menos convencional en términos geotécnicos, como es la exploración de la superficie de Marte mediante robots, ha sido presentado para examinar la metodología y la fiabilidad del modelo de interacción suelo-rueda de Wong y Reece; extensamente adoptado por la comunidad que trabajo en Terramecánica, pero aún no totalmente aceptada para robots ligeros como los que se han utilizado recientemente en las misiones de exploración de Marte.
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44

Daw, Pérez Zamira Angélica [Verfasser]. "Model-driven development methodology for hybrid embedded systems based on UML with emphasis on safety-related requirements / Zamira Angélica Daw Pérez." Kassel : Kassel University Press, 2014. http://d-nb.info/1065688636/34.

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45

Fabri, Peter J. "The validation of a methodology for assessing the impact of hybrid simulation training in the minimization of adverse outcomes in surgery." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002085.

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46

Getyengana, Nobayeni. "Effective implementation of a Hybrid project management methodology combining agile and traditional methods for IT-based projects in South African organisations." Diss., University of Pretoria, 2020. http://hdl.handle.net/2263/79580.

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It has been documented that Agile and Stage-Gate management approaches can be combined and used by technology companies to run technical projects effectively, making them more flexible and adaptable, to remain competitive in the fast-paced business world (Conforto & Amaral, 2016). Stage-Gate and Agile approaches can be used to achieve this in their own right, but there is risk of oversimplifying complex projects using Agile, and overcomplicating smaller projects using Stage-Gate. Therefore, this research examined the possibility of combining the two methods to derive a Hybrid method which would be suitable for most projects, whether simple or complex, and still achieve effectiveness, flexibility, and adaptability. This study evaluated factors for effectively implementing a Hybrid project management methodology along with the benefits and challenges of such implementation. This study undertook a mono-method qualitative study using interviews with thirteen participants who are key personnel involved in implementing IT-based projects in South African-based companies, to provide data that is timely, less costly, convenient, and to have in-depth knowledge of the subject to be able to accurately answer this study’s research questions. An interpretive research philosophy enabled the researcher to make sense of the phenomenon being studied in a natural setting, which allowed for trust to be established between the researcher and the interviewees. The researcher used a deductive approach to theory development to adopt a theoretical position that could be tested through data collection. The study used the Information Technology Management Framework (Pollard & Geisler, 2014), which consolidates the various phases of project lifecycle management into five simplified phases: request, define, build, deploy and run. The implementation of this cross-platform methodology empowers organisations to successfully implement a stable, adaptive reporting matrix at a strategic management level. This methodology provides timely monitoring and control along with the project lifecycle’s change from inception to beyond execution. Therefore, the ITMF can enable a Hybrid blend of various methodologies and models to form a single delivery-oriented ICT environment that helps Information Technology departments to deliver change at the speed of business. The study found that effective implementation of a Hybrid project management methodology relies on: a) reducing scope creeps in the request phase; b) offering sufficient Hybrid project. management methodology implementation training for project teams and having a well-defined financial model in the define phase; c) deploying highly skilled technical support in the build phase; d) maintaining active communication with all stakeholders, and creating an Agile and flexible project environment in the deploy phase; and lastly, e) enabling an organisational culture change in the run phase. These findings can motivate organisations to implement a Hybrid project management methodology that will facilitate project delivery success, therefore assisting in improving customer service levels and gaining optimal project performance that results in realising business profits.
Mini Dissertation (MBA)--University of Pretoria, 2020.
pt2021
Gordon Institute of Business Science (GIBS)
MBA
Unrestricted
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47

Phan, Leon L. "A methodology for the efficient integration of transient constraints in the design of aircraft dynamic systems." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34750.

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Transient regimes experienced by dynamic systems may have severe impacts on the operation of the aircraft. They are often regulated by dynamic constraints, requiring the dynamic signals to remain within bounds whose values vary with time. The verification of these peculiar types of constraints, which generally requires high-fidelity time-domain simulation, intervenes late in the system development process, thus potentially causing costly design iterations. The research objective of this thesis is to develop a methodology that integrates the verification of dynamic constraints in the early specification of dynamic systems. In order to circumvent the inefficiencies of time-domain simulation, multivariate dynamic surrogate models of the original time-domain simulation models are generated using wavelet neural networks (or wavenets). Concurrently, an alternate approach is formulated, in which the envelope of the dynamic response, extracted via a wavelet-based multiresolution analysis scheme, is subject to transient constraints. Dynamic surrogate models using sigmoid-based neural networks are generated to emulate the transient behavior of the envelope of the time-domain response. The run-time efficiency of the resulting dynamic surrogate models enables the implementation of a data farming approach, in which the full design space is sampled through a Monte-Carlo Simulation. An interactive visualization environment, enabling what-if analyses, is developed; the user can thereby instantaneously comprehend the transient response of the system (or its envelope) and its sensitivities to design and operation variables, as well as filter the design space to have it exhibit only the design scenarios verifying the dynamic constraints. The proposed methodology, along with its foundational hypotheses, is tested on the design and optimization of a 350VDC network, where a generator and its control system are concurrently designed in order to minimize the electrical losses, while ensuring that the transient undervoltage induced by peak demands in the consumption of a motor does not violate transient power quality constraints.
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48

Wu, Yiming. "ICT System Architecture for Smart Energy Container." Thesis, KTH, Industriella informations- och styrsystem, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-51382.

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Hybrid Energy Resource System (HERS) is studied and applied aroundworld in recent years. Control and monitor of them are quite important in realapplication. HERS also has the equirement to integral with power grid such asdistribution grid networks. Therefore, to design and implement the informationcommunication system following IEC 61850, which is most promising standard fordesign of substation communication and automation system, is necessary. This paperpresents the design of Information Communication Technology (ICT) architectureand Unified Modeling Language (UML) models and final implementation through LabVIEW programming for Smart Energy Container. Applying design following IEC61850 series standards allow the HERS can communicate and interoperate with other IEC61850 devices and SCADA systems. The implementation is applied to SmartEnergy Container which contains wind power, solar power, battery energy storagesystem, and hydrogen energy storage system. Verification and testing results shows thedesign is qualified to control and monitor Smart Energy Container.
Smart Energy Container
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49

Mesa, Akhilesh. "A Methodology to Design Systems to Support Fulfillment of Online Grocery Orders." Ohio University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1610708317139122.

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50

Quaratino, Marco. "Virtual Calibration of CO2 and Pollutant Emissions of a High-Performance PHEV using Model-in-the-Loop Methodology." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/22053/.

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The study analyses the calibration process of a newly developed high-performance plug-in hybrid electric passenger car powertrain. The complexity of modern powertrains and the more and more restrictive regulations regarding pollutant emissions are the primary challenges for the calibration of a vehicle’s powertrain. In addition, the managers of OEM need to know as earlier as possible if the vehicle under development will meet the target technical features (emission included). This leads to the necessity for advanced calibration methodologies, in order to keep the development of the powertrain robust, time and cost effective. The suggested solution is the virtual calibration, that allows the tuning of control functions of a powertrain before having it built. The aim of this study is to calibrate virtually the hybrid control unit functions in order to optimize the pollutant emissions and the fuel consumption. Starting from the model of the conventional vehicle, the powertrain is then hybridized and integrated with emissions and aftertreatments models. After its validation, the hybrid control unit strategies are optimized using the Model-in-the-Loop testing methodology. The calibration activities will proceed thanks to the implementation of a Hardware-in-the-Loop environment, that will allow to test and calibrate the Engine and Transmission control units effectively, besides in a time and cost saving manner.
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