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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.
381

Impact of supply chain security orientation on port performance

Park, Hong January 2013 (has links)
The terrorist attack at September 11, 2001 in the United States of America had a huge impact on the security of international cargo transportation. In order to minimize the threat of terrorism and secure the movement of goods in the supply chain, security initiatives such as ISPS code and CSI are adopted by the United Nations and the United States. Also, the term ‘security’ has emerged as an independent area of study in supply chain management studies after the 2000s. The objective of this study is to examine the impact of Supply Chain Security Orientation on Port Performance in the context of Korea. In order to explore the causal relationships, this study utilized Structural Equation Modelling (SEM) to examine the relationships. Also, a multi-group analysis between port group (port A and B) and port user group (shipping companies, forwarding companies, etc) was conducted to investigate the differences of the perceptions in two groups. This is to fill the gaps from previous studies by conducting quantitative and confirmatory research in the field of supply chain security. This study develops a conceptual model by literature review and semi-structured interviews in order to identify the impact of the constructs: Antecedents, Supply Chain Security Orientation, and Port Performance. There are 11 variables in total, and in-depth analysis of the inter-relationships among variables is identified. In conclusion, this study empirically develops a structural model and identified the importance of Financial Resources (FR), Supply Chain Security Initiatives (SCSI), Security Preparation and Planning (SPP), Security Related Partnership (SRP), Security Dedicated Communication and Technology (SDCT), Security Culture (SC), and Security Education (SE) on Port Performance. Also, the differences in perceptions between port group and port user group of the variables in the construct were also explored.
382

Price of anarchy for congestion games with stochastic demands

Wang, Chenlan January 2014 (has links)
The price of anarchy is a game-theoretical concept and it measures system degradation caused by players' selfish behaviours. This thesis extends models of congestion games to take stochastic demands into account and studies the price of anarchy on the basis of generalised models developed in this research. In the presence of stochastic demands, the models developed in this study better re flect the reality of a transportation network. The study would help provide a theoretical foundation and insights into mechanism design of transportation games and traffic control in practice. This thesis is concerned with both non-atomic and atomic congestion games, which involve an infinite and finite number of travellers respectively. We introduce the notions of user equilibrium and system optimum under stochastic demands and investigate the behaviours of travellers and central coordinators in a stochastic environment. At a user equilibrium, travellers choose routes independently and aim to minimise their own expected travel costs, while at a system optimum, traffic is fully coordinated to minimise the expected total cost over the whole network. We extend two existing methods of bounding the price of anarchy and compute the quality upper bounds for polynomial cost functions and very general settings of demand distributions. More specifically, we consider positive-valued distributions and normal distributions for non-atomic congestion games, and positive-valued discrete distributions for atomic congestion games. Our results show that the price of anarchy depends on the class of cost functions, demand distributions and, to some extent, network topologies. All the upper bounds are tight in some special cases, including the case of deterministic demands. The two bounding methods are also compared.
383

A macro-level analysis of traffic and pedestrian safety in urban areas

Najaf, Pooya 05 May 2017 (has links)
<p> The main objective of this research is to examine the effect of city-level urban characteristic, such as urban form and trip generation factors, on traffic safety in general and pedestrian safety in particular. For this purpose, the information for 100 major Urban Areas (UAs) in the United States in 2010 is studied. Factor analysis is applied to construct latent variables from multiple observed variables to measure and describe urban form, macro-level trip generation, citywide transportation network features and traffic safety. Structural Equation Modeling (SEM) is then used to investigate how city-level urban form and trip generation affect traffic safety directly and indirectly (through mediators of transportation network features).</p><p> Based on the statistical analysis, it is found that encouraging the use of non-driving transportation modes and controlling traffic congestion, as significant mediators, are effective policies to increase overall traffic safety and pedestrian safety, respectively. In this regard, urban areas with a more even spatial distribution of job-housing balance (more polycentricity), more uniform spatial distribution of different social classes, higher urban density (less sprawl), and more connectivity in their transportation network (more accessibility) have the safest urban form designs.</p><p> Moreover, mixed land-use designs with provided local access to services and amenities, food and beverage centers, and religious organizations, followed by strict pedestrian safety standards for neighborhoods are the safest type of land use designs in urban areas. In addition, regulating the off-peak hours allowed time for heavy vehicles and changing the work schedule of workers who do not reside in the urban area can also help city planners to increase traffic safety.</p>
384

Ford Evoke

Goraczkowski, Sebastian January 2016 (has links)
„ What if Adaptive Personalization excelled Hardware Customization? “ Adaptive Vehicle Personalization Human mobility is about to create a generation of " Movers"  - a new breed of mobility users with global transportation  needs and a connection to multiple urban areas  already from a young age. Expectations towards mobility go towards adaptable and personalized solutions and technological advancements should enable a strategy in which one vehicle could adapt to multiple qualities. The final result is an adaptable urban mobility solution designed for global membership use in the year 2025. The intention of the project has been to holistically investigate how Vir tual Reality can influence the design process and result of interior and exterior. The goal has been to inspire and to show a believable way of how in the future adaptive personalization could excel hardware customization in order to suit the different and changing needs of various mobility service users.
385

Regional airline pilot commute| How commuting by air affects pilots' satisfaction with life

Kleinfehn, Andrew David 02 February 2017 (has links)
<p> At a time of increased use and competitiveness amongst U.S. regional airlines, and the growing pilot shortage, regional air carriers and pilots alike lack proper understanding how pilot commutes by airplane affect satisfaction with life. There are numerous studies on how commuting by vehicle, bicycle, mass transit system, or walking (traditional commute) to and from work affects one&rsquo;s satisfaction with life. There are no identified studies which investigate regional airline pilots&rsquo; commute by airplane and its affect on satisfaction with life.</p><p> The purpose of this study was to gain knowledge on regional airline pilot commutes, how commuting affects regional pilots&rsquo; satisfaction with life, and to explore why regional airline pilots choose to commute. This study used both qualitative and quantitative measures to accomplish this task by imploring a mixed methods exploratory sequential design. The two research questions were what is the variation in the Satisfaction With Life Scale scores between different groups of regional pilots and what aspects of pilot commuting are related to traditional commuting?</p><p> This study used previous related research and regional airline pilot qualitative interviews to build a quantitative survey to measure satisfaction with life. The survey was distributed to a large regional airline to get a representative pilot population sample response. Statistical analysis was conducted on the responses which looked for significance between different groups of regional airline pilots.</p><p> Results from a t-test indicated that there is a significant difference in Satisfaction With Life Scores for regional pilots that are able to traditionally commute to their domicile vs. regional pilots who commute by airplane to their domicile. Further t-test results indicated that there is a significant difference in satisfaction with life for airplane commute captains vs. traditional commute captains, and airplane commute captains vs. traditional commute first officers. When only airplane commute pilots were analyzed, there are significant differences in satisfaction with life for pilots that commute over 43.33 hours a month (equivalent to one hour, one way traditional commute), and a one way airplane commute of two or more legs. A Between-Groups ANOVA indicated that commuting the day before a trip begins and commuting the day after a trip ends (un-commutable trip) produces a less satisfied pilot compared to trips that are commutable at the beginning, end or both ends.</p>
386

Decision tree-based machine learning algorithm for in-node vehicle classification

Trivedi, Ankit P. 04 January 2017 (has links)
<p> This paper proposes an in-node microprocessor-based vehicle classification approach to analyze and determine the types of vehicles passing over a 3-axis magnetometer sensor. The approach for vehicle classification utilizes J48 classification algorithm implemented in Weka (a machine learning software suite). J48 is Quinlan's C4.5 algorithm, an extension of decision tree machine learning based on an ID3 algorithm. The decision tree model is generated from a set of features extracted from vehicles passing over the 3-axis sensor. The features are attributes provided with correct classifications to the J48 training algorithm to generate a decision tree model with varying degrees of classification rates based on cross-validation. Ideally, using fewer attributes to generate the model allows for the highest computational efficiency due to fewer features needed to be calculated while minimalizing the tree with fewer branches. The generated tree model can then be easily implemented using nested if-loops in any language on a multitude of microprocessors. Also, setting an adaptive baseline to negate the effects of the background magnetic field allows reuse of the same tree model in multiple environments. The result of the experiment shows that the vehicle classification system is effective and efficient.</p>
387

National Promotion of Western Roads and Canals, 1785-1830

Hoffmann, John R. 08 1900 (has links)
This thesis discusses the development of roads and canals as a means of transportation and communication in the years following the Revolutionary War.
388

Solving Linear Programming's Transportation Problem

Culp, William E. 05 1900 (has links)
A special case of the linear programming problem, the transportation problem, is the subject of this thesis. The development of a solution to the transportation problem is based on fundamental concepts from the theory of linear algebra and matrices.
389

Risk management in international container logistics operations : risk analysis and mitigating strategies

Kwak, Dong-Wook January 2014 (has links)
Purpose: The aim of this thesis is to investigate risk management strategies for international logistics operations that can minimise the occurrence and/or the impact of risks in order to achieve a desirable logistics network. For this purpose, international logistics risks were analysed to find out critical risk areas, and then strategies to mitigate those risks were developed and validated in relation to organisational orientations and outcomes. Methodology: Risk identification, risk clustering and risk analysis were conducted by using focus group research and Interpretive Structural Modelling (ISM) to investigate risk areas that should be mitigated. A risk management strategy model was developed using Information Processing Theory, a review of extant supply chain risk management studies and interviews with logistics practitioners. The model was empirically tested with questionnaire survey data using descriptive statistics, ANOVA and Partial Least Square Structural Equation Modelling (PLS-SEM). Findings: International logistics risks consists of value streams; information and relationships; logistics activities; and the external environments. Among these, information and relationships risks were found to generate self-enhancing risk loops, thereby creating subsequent risk impacts after disruptions. To mitigate these risks, firms involved in international logistics implemented strategies, such as building a stable logistics network, leveraging logistics information, leveraging outsourcing contracts and developing logistics collaboration, although the level of implementation depends on the business context. Among the four strategies, building a stable logistics network and developing logistics collaboration strategies were most effective in strengthening both robustness and resilience in the logistics network. Customer orientation had positive impacts on all four strategies, but disruption orientation and quality orientation influenced certain types of strategies. Research Implications: This is the first study which has applied a three-phase risk management process to international logistics operations, thereby highlighting distinctive features of international logistics risks. This thesis empirically develops and validates a risk management strategy model which embraces both strategies and relevant tactical/operational initiatives. The antecedents and outcomes of risk management strategies were also investigated and conceptualised for future research. Practical Implications: The profile of risks, risk sources, loss types and risk levels provide a guideline for logistics managers to anticipate and proactively deal with potential risks. Also, they can evaluate the current status of risk management efforts and can benchmark suggested strategies and practices in consideration of the strategic fit to their organisations.
390

Development of a process driven approach to improving supply chain performance within the airline service industry : executive summary

Karim, Javid January 2002 (has links)
This programme of research investigated the development of a process driven approach to improving supply chain performance within the airline service sector. Work was undertaken within the Engineering division of an established UK scheduled airline, and specifically within the maintenance, repair and overhaul sector (MRO). The underlying objective of this research was to establish the relevance of supply chain management as a source of competitive advantage to the airline service sector. A detailed review of the literature revealed that best practice originated predominately from the Japanese automotive sector, notably a manufacturing based industry. A review of the characteristic differences between these two industry sectors was undertaken to identify the opportunity for cross-sectoral transfer of knowledge. This was complemented by a thorough benchmarking analysis that identified the airline industry's position relative to best practice. This confirmed the relative immaturity of supply chain management within the airline service sector, which was representative of progress achieved by the automotive sector in the early 1980's. The key aspects of best practice were then structured into a proposed process for improving supply chain performance. This process consisted of specific strategies with their corresponding tools and techniques for implementation. A number of case study implementations were then used to further validate, test and develop this generic process within a real airline operational environment. Significant improvements in both operational and financial performance were achieved through adopting this approach. A 40 % reduction in chemical sourcing costs was achieved, representing a £990,000 saving over three years for the case study company. A further 12.5 % reduction in landing gear overhaul costs was achieved (approximately £300,000), whilst at the same time improving the operational performance of this supply chain by 60 %. This research concludes by recommending a generic process for improving supply chain performance. The benefits achieved through implementing this process further confirm the relevance of supply chain management to the airline service sector. Finally, this paper proposes a deterministic tool to assist practitioners in the selection of the most appropriate supply chain strategy for a given situation. Whilst this tool requires further validation, the possibilities for it's application extend far beyond those of the airline service sector. As a result this work has significantly contributed to knowledge in the field, representing considerable innovation.

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