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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

New Product Development and Innovation Through Joint Knowledge Creation and Transfer in a Dyadic Supply Chain Relationship

Miller, Richard John 05 May 2010 (has links)
No description available.
322

National Security Policy Complexity: An Analysis of U.S. Defense Security Cooperation Program Effects on Political Terror

Hightower, Rudolph L., II January 2017 (has links)
No description available.
323

Modeling and control of a hybrid electric drivetrain for optimum fuel economy, performance and driveability

Wei, Xi 01 December 2004 (has links)
No description available.
324

Fundamental studies for development of real-time model-based feedback control with model adaptation for small scale resistance spot welding

Chen, Jianzhong 02 March 2005 (has links)
No description available.
325

Development of a Dynamic Model of a Counterflow Compact Heat Exchanger for Simulation of the GT-MHR Recuperator using MATLAB and Simulink

Hawn, David Phillip 27 August 2009 (has links)
No description available.
326

System Dynamics Modeling and Development of a Design Procedure for Short-term Alternative Energy Storage Systems

McDonough, Joshua 08 September 2011 (has links)
No description available.
327

Seeds of (inter)action : Applying amplification and systems approaches to seed initiatives in Italy

Voigt, Franca Josefa January 2022 (has links)
Seeds are essential elements within agricultural production and food systems. However, seed systems face multiple issues, including processes of commercialisation, privatisation, and crop diversity loss, that require reconsidering current approaches to seeds and varieties. Seed initiatives hold a potential to contribute to alternative and desirable seed system configurations and outcomes. In this thesis, I analyse how existing seed initiatives increase their impact, drawing on the typology of amplification processes by Lam et al. (2020). Furthermore, due to the long-term occurrence of variety losses and the complexity of the processes involved, this thesis uses system dynamics concepts and diagramming tools to map the use of local varieties from the initiatives’ perceptions. Thereby, I attempt to operationalise amplification, depict local variety use, and combine the two approaches within the context of seed initiatives. I employ a case-study approach in Italy and conducted semi-structured interviews with members of six seed initiatives. Concrete actions for almost all the frameworks’ processes were found. Building stability, influencing values and mindsets, and strategically impacting higher institutional levels emerged as suitable ways to amplify and might indicate that initiatives prepare and potentially navigate change. Enhancing the initiatives’ impact range and speed benefitted from more nuance due to diverging notions on these processes. A qualitative systems diagram with social and ecological components maps causal structures that influence the use of local varieties, showing a potential for desirable dynamics. By indicating how amplifying actions relate to the system structure, I illustrate how the seed initiatives are influencing multiple system parts. Thus, the system maps revealed perceived system structure, which by itself might run the risk of portraying path dependency, while amplification relates to agency on how initiatives might influence the system.
328

A Transportation Planning Model for State Highway Management: A Decision Support System Methodology to Achieve Sustainable Development

Kim, Kyeil 19 February 1998 (has links)
The realization that the U.S. infrastructure is deteriorating and that there is a need to establish a strategy to prevent an infrastructure catastrophe have propelled the development of various infrastructure management systems. Often, the expansion of transportation facilities is regarded as a means to the improvement of the condition of transportation infrastructure. However, building more infrastructure than can be properly maintained causes serious deterioration of the existing infrastructure. Sustainable development from a highway management perspective can be equated with qualitative development, which improves the current condition of the highway system, rather than expanding its physical resources. The objective of this research is to develop a highway management strategy to help achieve sustainable development for the Commonwealth of Virginia. This research is performed by developing a transportation planning model for state highway management (TPMSHM) within the framework of a decision support system (DSS). The planning model consists of ten subsystems, including pavement and bridge management subsystems. These subsystems encompass various socioeconomic parameters that influence the physical status of highways. In the dynamic simulation model, these parameters are expressed in causal relationships using a system dynamics methodology. The types of trajectories for highway conditions that lead to sustainable development are provided. This research proposes a state-dependent prioritization strategy for calculating efficient budget shares by hierarchical levels of highway conditions. In this strategy, the proportions of the highway budget allocated to each level of management activity are determined by the physical conditions of the highways. Highways in the worst condition are given the first priority to receive the budget allocations. The model also addresses the policy of raising fuels tax to increase the state's transportation revenue. The adverse impact of a fuels tax increase is discussed in terms of revenue, the physical sufficiency of highways, and user benefits. The TPMSHM constitutes a leading component of the DSS and governs the building processes of other two components, which include a Data Base and a Display Base. A Data Base is constructed by listing all the parameters needed by the TPMSHM within a frame designed in terms of the records and fields of the parameters. A Display Base is demonstrated in a possible form using system dynamics' Powersim software. The graphical capability of representing the simulation results and the interactive user interface inherent in the software are examined. The emphasis of this research is placed on the development of the TPMSHM, which strives to manage the physical condition of the state highway system at an acceptable level through a state-dependent prioritization strategy to achieve sustainable development. / Ph. D.
329

A System Dynamics Approach Linking Employee Health, Quality Culture and Organizational Effectiveness

Sadia, Rina 04 May 2006 (has links)
The purpose of this research is to investigate the interactions between organizational effectiveness, quality culture, and employee health. The system dynamics modeling approach is used in order to reveal the complex and dynamic behavior of the system under investigation. Understanding system behavior facilitates policy analysis and management decision-making. The relationships between the three constructs: organizational effectiveness, quality culture and employee health are non linear and during the research a number of dynamic hypotheses were investigated. For example, illness is the main cause for absenteeism, loss of productivity, ineffective learning, which in turn causes even more stress and eventually more illness. As part of the system dynamics approach a conceptual (qualitative) model and a formal (quantitative) model were built. The conclusion from analyzing the dynamic hypotheses of this model was that quality culture had a great impact on the performance of the whole system, especially on employees’ health and on organizational effectiveness. Furthermore, employees’ health and organizational effectiveness concurrently impact each other. However, this research could not show a considerable impact of the employees’ health and organizational effectiveness on the organization’s quality culture. The research contributes to the general understanding of complex production systems, since the three constructs investigated in this research face similar issues, i.e., the trade-off between long-term and short-term goals, consequences of managerial actions that are far apart in time and space, and conflicts between measurable outcomes and subjective outcomes. The research adds to the design of effective social systems, where the products and the services are created in a quality fashion, and individuals experience an environment that is conducive to their well-being. / Ph. D.
330

Three Essays on Travel Demand Management Strategies for Traffic Congestion Mitigation

Liu, Shiyong 22 January 2008 (has links)
This dissertation provides three essays. In the first essay, a model with two linguistic variables is built to demonstrate the joint effect of multiple linguistic variables in a dynamic modeling context. Triangular membership function is used to represent the linguistic variables and the joint effect is captured through fuzzy inference method. In this essay, the results obtained by employing fuzzy concepts are compared with the results that one would obtain using generic lookup functions. The second essay develops a system dynamics model by which policy makers can assess the impact of various travel demand management interventions within a metropolitan area and as a consequence understand the complex behavior of affected transportation-socioeconomic systems. This essay builds on a previously formulated approach where fuzzy concepts are used to represent five linguistic variables used in the model. We also compare the level of traffic congestion under the scenarios with and without traffic congestion pricing. The third essay is based on the second essay where different scenarios of the travel demand management policies are evaluated and analyzed. There are two parts in this essay. The first part addresses the construction of a Management Flight Simulator (MFS) that is used to do policy analysis for travel demand management policies. By using the Management Flight Simulator, the second part of the essay describes the evaluation of alternative travel demand management policies. In this research, we found that the revenue generated from congestion pricing does increase mass transit capacity even with the aging of mass transit capacity. However, in the short term traffic congestion is mitigated while in the long term the proposed travel demand management policy actually deteriorates the traffic situation. / Ph. D.

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