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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.
441

Understanding the Role of Sport for Development in Community Capacity Building in a Refugee Camp in Tanzania

Wright, Ryan Ward 06 August 2009
In the past decade a rapid increase has been seen in the number of organizations using sport as a development tool in majority world communities. Specifically, Sport for Development programs have been promoted as a means to promote peace, a forum for social mobilization efforts and health initiatives, and a tool for sustainable community development (SDP IWG, 2008; UNIATF, 2003). Often, a fundamental goal of such programs is community capacity building. However, despite this increase in attention, data regarding benefits of these programs remains anecdotal, without a strong body of reliable evidence on the impact of Sport for Development programs on community capacity building. Informed by this context, the purpose of this study was to understand the effectiveness of a Sport for Development program in community capacity building in a refugee camp in Tanzania.<p> The research was accomplished using a qualitative case study approach with 12 key stakeholders involved in the program. The principal method of data collection was a participatory workshop methodology using Laveracks (1999) nine domains to assess community capacity. This qualitative workshop methodology also employed a quantitative tool vis-à-vis Laveracks nine domains which acted as a participatory guide to evaluate the level of community capacity in the program. An initial workshop held with key stakeholders assessed current status, which was followed by the development and implementation of strategic plans for action by stakeholders based on the workshop assessment. A second workshop was held one year later to re-assess community capacity. Additional methods of data collection included individual interviews, observations, and field notes. Member checking, a prolonged time in the field, and triangulation were the primary procedures for verifying the accuracy of the findings.<p> The results showed that community capacity was increased in eight of the nine domains. Specifically, these eight were community participation, local leadership, organizational structures, problem assessment capacities, resource mobilization, ability to ask why, role of outside agents, and program management. The findings from this study demonstrate that a Sport for Development program can be effective in increasing community capacity; this was attributed to the specific participatory methodology used to assess community capacity, structural changes in the program, and a change in approach to programming by project coordinators.
442

Interference Mitigation for Cellular Networks: Fundamental Limits and Applications

Zhou, Lei 20 March 2013 (has links)
Interference is a key limiting factor in modern communication systems. In a wireless cellular network, the performance of cell-edge users is severely limited by the intercell interference. This thesis studies the use of interference-channel and relay-channel techniques to mitigate intercell interference and to improve the throughput and coverage of cellular networks. The aim of this thesis is to demonstrate the benefit of the proposed interference mitigation schemes through both information theoretical studies and applications in the cellular network. There are three mains results in this thesis: First, it is shown that for the $K$-user cyclic Gaussian interference channel, where the $k$th user interferes with only the ($k -1$)th user (mod $K$) in the network, the Etkin-Tse Wang power splitting strategy achieves the capacity region to within 2 bits in the weak interference regime. For the special 3-user case, this gap can be sharpened to $1\frac{1}{2}$ bits by the time-sharing technique. Second, it is shown that for a two-user Gaussian interference channel with an in-band-reception and out-of-band transmission relay, generalized hash-and-forward together with Han-Kobayashi information splitting can achieve the capacity region of this channel to within a constant number of bits in a certain weak-relay regime. A generalized-degrees-of-freedom analysis in the high signal-to-noise ratio regime reveals that in the symmetric channel setting, each common relay bit improves the sum rate up to two bits. The third part of this thesis studies an uplink multicell joint processing model in which the base stations are connected to a centralized processing server via rate-limited digital backhaul links. This thesis proposes a suboptimal achievability scheme employing the Wyner-Ziv compress-and-forward relaying technique and successive-interference-cancellation decoding. The main advantage of the proposed approach is that it results in achievable rate regions that are easily computable, in contrast to previous schemes in which the rate regions can only be characterized by exponential number of rate constraints.
443

Upper gradients and Sobolev spaces on metric spaces

Färm, David January 2006 (has links)
The Laplace equation and the related p-Laplace equation are closely associated with Sobolev spaces. During the last 15 years people have been exploring the possibility of solving partial differential equations in general metric spaces by generalizing the concept of Sobolev spaces. One such generalization is the Newtonian space where one uses upper gradients to compensate for the lack of a derivative. All papers on this topic are written for an audience of fellow researchers and people with graduate level mathematical skills. In this thesis we give an introduction to the Newtonian spaces accessible also for senior undergraduate students with only basic knowledge of functional analysis. We also give an introduction to the tools needed to deal with the Newtonian spaces. This includes measure theory and curves in general metric spaces. Many of the properties of ordinary Sobolev spaces also apply in the generalized setting of the Newtonian spaces. This thesis includes proofs of the fact that the Newtonian spaces are Banach spaces and that under mild additional assumptions Lipschitz functions are dense there. To make them more accessible, the proofs have been extended with comments and details previously omitted. Examples are given to illustrate new concepts. This thesis also includes my own result on the capacity associated with Newtonian spaces. This is the theorem that if a set has p-capacity zero, then the capacity of that set is zero for all smaller values of p.
444

TCP/IP i taktiska ad hoc-nät / TCP/IP in tactical ad hoc networks

Persson, Katarina January 2002 (has links)
TCP (Transmission Control Protocol) is a transport protocol designed for the wired Internet. In wireless networks packet losses occur more frequently due to the unreliability of the physical link. The main problem is that TCP treats all losses as congestion, which leads to a lower throughput. Ad hoc networks are multihop wireless networks of mobile nodes, where each node can allow other packets to pass through it. Topology changes often occur and may lead to packet losses and delays, which TCP misinterprets as congestion. We want to modify TCP to recognize the differences between link failure and congestion to improve the capacity. In our model we have built a connection in an ad hoc network where packet losses and partitions can be made. Simulation experiments show that we didn't get the problems we expected. This can be explained by low delays and because we buffered the packets during link failure. A simple modification of TCP was made and simulated, and showed that an improvement of performance is possible. More research should be done to make a modification of TCP that would further affect the throughput.
445

Performance issues in cellular wireless mesh networks

Zhang, Dong 14 September 2010
This thesis proposes a potential solution for future ubiquitous broadband wireless access networks, called a cellular wireless mesh network (CMESH), and investigates a number of its performance issues. A CMESH is organized in multi-radio, multi-channel, multi-rate and multi-hop radio cells. It can operate on abundant high radio frequencies, such as 5-50 GHz, and thus may satisfy the bandwidth requirements of future ubiquitous wireless applications.<p> Each CMESH cell has a single Internet-connected gateway and serves up to hundreds of mesh nodes within its coverage area. This thesis studies performance issues in a CMESH, focusing on cell capacity, expressed in terms of the max-min throughput. In addition to introducing the concept of a CMESH, this thesis makes the following contributions.<p> The first contribution is a new method for analyzing theoretical cell capacity. This new method is based on a new concept called Channel Transport Capacity (CTC), and derives new analytic expressions for capacity bounds for carrier-sense-based CMESH cells.<p> The second contribution is a new algorithm called the Maximum Channel Collision Time (MCCT) algorithm and an expression for the nominal capacity of CMESH cells. This thesis proves that the nominal cell capacity is achievable and is the exact cell capacity for small cells within the abstract models.<p> Finally, based on the MCCT algorithm, this thesis proposes a series of greedy algorithms for channel assignment and routing in CMESH cells. Simulation results show that these greedy algorithms can significantly improve the capacity of CMESH cells, compared with algorithms proposed by other researchers.
446

Optimal Pricing and Capacity Planning in Operations Management

Tong, Dehui 16 November 2011 (has links)
Pricing and capacity allocation are two important decisions that a service provider needs to make to maximize service quality and profit. This thesis attempts to address the pricing and capacity planning problems in operations management from the following three aspects. We first study a capacity planning and short-term demand management problem faced by firms with industrial customers that are insensitive to price incentives when placing orders. Industrial customers usually have downstream commitments that make it too costly to instantaneously adjust their schedule in response to price changes. Rather, they can only react to prices set at some earlier time. We propose a hierarchical planning model where price decisions and capacity allocation decisions must be made at different points of times. Customers first sign a service contract specifying how capacity at different times will be priced. Then, when placing an order, they choose the service time that best meets their needs. We study how to price the capacity so that the customers behave in a way that is consistent with a targeted demand profile at the order period. We further study how to optimally allocate capacity. Our numerical computations show that the model improves the operational revenue substantially. Second, we explore how a profit maximizing firm is to locate a single facility on a general network, to set its capacity and to decide the price to charge for service. Stochastic demand is generated from nodes of the network. Customers demand is sensitive to both the price and the time they expect to spend on traveling and waiting. Considering the combined effect of location and price on the firm's profit while taking into account the demand elasticity, our model provides managerial insights about how the interactions of these decision variables impact the firm's profit. Third, we extend this single facility problem to a multiple facility problem. Customers have multiple choices for service. The firm maximizes its profit subject to customers' choice criteria. We propose a system optimization model where customers cooperate with the firm to choose the facility for service and a user equilibrium model where customers choose the facilities that provide the best utility to them. We investigate the properties of the optimal solutions. Heuristic algorithms are developed for the user equilibrium model. Our results show that capacity planning and location decisions are closely related to each other. When customers are highly sensitive to waiting time, separating capacity planning and location decisions could result in a highly suboptimal solution.
447

Canada Reaching Out? A Study of Collaboration between Canada and the Emerging Economies in Health Biotechnology

Ray, Monali 11 January 2012 (has links)
This dissertation discusses research on Canada’s collaboration with emerging economies, specifically Brazil and India, in the field of health biotechnology. In recent years Canada has shown interest in engaging with emerging economies including Brazil and India in S&T fields. However, little is known about the levels and characteristics of such collaboration. Without greater understanding of this phenomenon it is difficult to inform public policy on how to best encourage collaboration. In this dissertation, the levels of Canada-emerging economies research and entrepreneurial collaboration are gauged. The motivations driving Canada-emerging economies research as well as entrepreneurial collaboration, its challenges and outcomes are examined. The roles of wider institutional actors – funding agencies, intellectual property experts, regulators, etc – in both Canada and the two emerging economies that support international collaboration are analyzed. The research reveals that north-south collaboration in health biotechnology has the potential to lead to a wide range of scientific and commercial benefits for both partners. They include access to expertise, technologies, biodiversity, as well as increasing potential to publish in high impact journals. The benefits are mutual. Northern academics and entrepreneurs are not necessarily in a dominant position in the partnerships, thus contradicting stereotypical notions of partners in north-south relationships. The systems of innovation conceptual framework is useful to uncover how institutions in both the north and the south shape S&T collaboration, and also to develop multi-pronged policy approaches to promote such partnerships and mitigate risks. The framework enables moving away from a donor-recipient, linear model of S&T interactions between the north and the south, and towards conceptualizing north-south collaboration as complex interplay of two innovation systems.
448

Optimal Pricing and Capacity Planning in Operations Management

Tong, Dehui 16 November 2011 (has links)
Pricing and capacity allocation are two important decisions that a service provider needs to make to maximize service quality and profit. This thesis attempts to address the pricing and capacity planning problems in operations management from the following three aspects. We first study a capacity planning and short-term demand management problem faced by firms with industrial customers that are insensitive to price incentives when placing orders. Industrial customers usually have downstream commitments that make it too costly to instantaneously adjust their schedule in response to price changes. Rather, they can only react to prices set at some earlier time. We propose a hierarchical planning model where price decisions and capacity allocation decisions must be made at different points of times. Customers first sign a service contract specifying how capacity at different times will be priced. Then, when placing an order, they choose the service time that best meets their needs. We study how to price the capacity so that the customers behave in a way that is consistent with a targeted demand profile at the order period. We further study how to optimally allocate capacity. Our numerical computations show that the model improves the operational revenue substantially. Second, we explore how a profit maximizing firm is to locate a single facility on a general network, to set its capacity and to decide the price to charge for service. Stochastic demand is generated from nodes of the network. Customers demand is sensitive to both the price and the time they expect to spend on traveling and waiting. Considering the combined effect of location and price on the firm's profit while taking into account the demand elasticity, our model provides managerial insights about how the interactions of these decision variables impact the firm's profit. Third, we extend this single facility problem to a multiple facility problem. Customers have multiple choices for service. The firm maximizes its profit subject to customers' choice criteria. We propose a system optimization model where customers cooperate with the firm to choose the facility for service and a user equilibrium model where customers choose the facilities that provide the best utility to them. We investigate the properties of the optimal solutions. Heuristic algorithms are developed for the user equilibrium model. Our results show that capacity planning and location decisions are closely related to each other. When customers are highly sensitive to waiting time, separating capacity planning and location decisions could result in a highly suboptimal solution.
449

Canada Reaching Out? A Study of Collaboration between Canada and the Emerging Economies in Health Biotechnology

Ray, Monali 11 January 2012 (has links)
This dissertation discusses research on Canada’s collaboration with emerging economies, specifically Brazil and India, in the field of health biotechnology. In recent years Canada has shown interest in engaging with emerging economies including Brazil and India in S&T fields. However, little is known about the levels and characteristics of such collaboration. Without greater understanding of this phenomenon it is difficult to inform public policy on how to best encourage collaboration. In this dissertation, the levels of Canada-emerging economies research and entrepreneurial collaboration are gauged. The motivations driving Canada-emerging economies research as well as entrepreneurial collaboration, its challenges and outcomes are examined. The roles of wider institutional actors – funding agencies, intellectual property experts, regulators, etc – in both Canada and the two emerging economies that support international collaboration are analyzed. The research reveals that north-south collaboration in health biotechnology has the potential to lead to a wide range of scientific and commercial benefits for both partners. They include access to expertise, technologies, biodiversity, as well as increasing potential to publish in high impact journals. The benefits are mutual. Northern academics and entrepreneurs are not necessarily in a dominant position in the partnerships, thus contradicting stereotypical notions of partners in north-south relationships. The systems of innovation conceptual framework is useful to uncover how institutions in both the north and the south shape S&T collaboration, and also to develop multi-pronged policy approaches to promote such partnerships and mitigate risks. The framework enables moving away from a donor-recipient, linear model of S&T interactions between the north and the south, and towards conceptualizing north-south collaboration as complex interplay of two innovation systems.
450

バッファを考慮にいれたジョブショップスケジューリング

樋野, 励, HINO, Rei, 楠見, 哲也, KUSUMI, Tetsuya, 柳, 在圭, YOO, Jae-Kyu, 清水, 良明, SHIMIZU, Yoshiaki 02 1900 (has links)
No description available.

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