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Many large-scale random graphs (e.g., the Internet) exhibit complex topology, nonhomogeneous spatial node distribution, and preferential attachment of new nodes. Current topology models for ad-hoc networks mostly consider a uniform spatial distribution of nodes and do not capture the dynamics of evolving, real-world graphs, in which nodes "gravitate" toward popular locations and self-organize into non-uniform clusters. In this thesis, we first investigate two constraints on scalability of ad-hoc networks – network reliability and node capacity. Unlike other studies, we analyze network resilience to node and link failure with an emphasis on the growth (i.e., evolution) dynamics of the entire system. Along the way, we also study important graph-theoretic properties of ad-hoc networks (including the clustering coefficient and the expected path length) and strengthen our generic understanding of these systems. Finally, recognizing that under existing uniform models future ad-hoc networks cannot scale beyond trivial sizes, we argue that ad-hoc networks should be modeled from an evolution standpoint, which takes into account the well-known "clustering" phenomena observed in all real-world graphs. This model is likely to describe how future ad-hoc networks will self-organize since it is well documented that information content distribution among end-users (as well as among spatial locations) is non-uniform (often heavy-tailed). Results show that node capacity in the proposed evolution model scales to larger network sizes than in traditional approaches, which suggest that non-uniformly clustered, self-organizing, very large-scale ad-hoc networks may become feasible in the future.

While lean manufacturing has greatly improved the efficiency of production operations, it has left US enterprises in an increasingly risky environment. Causes of manufacturing disruptions continue to multiply, and today, seemingly minor disruptions can cause cascading sequences of capacity losses. Historically, enterprises have lacked viable tools for addressing operational volatility. As a result, each year US companies forfeit billions of dollars to unpredictable capacity disruptions and insurance premiums. In this dissertation we develop a number of stochastic models that capture the dynamics of capacity disruptions in complex multi-tier flow-matching feed-forward networks (FFN). In particular, we relax basic structural assumptions of FFN, introduce random propagation times, study the impact of inventory buffers on propagation times, and make initial efforts to model random network topology. These stochastic models are central to future methodologies supporting strategic risk management and enterprise network design.

Alliance has become a necessary part of firms¡¦ strategy due to fast-paced diffusion of technologies, rising costs and protectionism. While the forms of strategy alliances evolve from simple contracts into multiple cooperation modes, factors needed to be considered are also gaining amount. Different kinds of strategy alliances possess different kinds of pros and cons, and will have effect on integration of resources and techniques. This research aims at analyzing whether the property of knowledge, firms¡¦ capacity and partner relations had effect on the selection of the strategy alliance modes. This study also formed a questionnaire survey which empirically tested the hypotheses set up in the study with data from public offering electronic firms. The results are indicating that contractual alliances are more likely to be formed when the absorptive capacity and risks are high, which are supported by numerous papers. The reason is that the strategy alliance is a channel of knowledge transferring, and higher the potential of gaining knowledge, then easier the process would be ¡V no resource-committing equity alliances are needed. The risk part is talking similar story: while risks are high, firms tend to serve contract as a tool of controlling loses. The level of implicit and complexity of knowledge are also positively related with the preference of committing equity alliances. The reason is that these kinds of alliances would serve better for firms to cooperate with each others and to transfer complex and tacit knowledge easier

Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 57-59).

The purpose of this study was to include consideration for intersections into the previously created GIS traffic control planning tool. Available data for making intersection control calculations were collected and integrated into the design of the tool. The limitations created by required assumptions were addressed, as well as more advanced techniques for overcoming these problems. The tool can be use to estimate capacity calculations at any signalized intersection within the NCTCOG modeling region. These calculations can be used to inform users about the effects of a construction plan. Inputs for using dynamic traffic assignment to further understand these effects is then addressed, focusing on the development of a subnetwork to reduce computation time for multiple temporary traffic control plans. / text

A database with 217 cases of load tests on shallow foundations, mostly in/on granular soils, was compiled. With this information, the comparison of predicted bearing capacity using different design methods, the American Petroleum Institute Recommended Practice 2A-LRFD (API RP2A-LRFD,1989), the American Petroleum Recommended Practice 2GEO (API RP2GEO, 2011), and International Standard Organization (ISO, 2003) is carried out. The answer to which standard makes a good prediction varies with the way to define failure load from load-displacement curve. Overall, ISO has a higher prediction compared with API RP2A and API RP2GEO. For the cases with vertical concentric loading conditions, if the capacity at plastic region and is defined as failure load, then the prediction by API RP2A is closest to measured capacity. If the capacity corresponding with 10% of footing width is considered as failure load, then the API RP2A and API RP2GEO underestimate the capacity, while ISO is in a good agreement with capacity corresponding with 10% of footing width. The prediction by API RP2GEO generally has a good agreement with capacity at tangent intersection region. In most of the cases with vertical eccentric loading, all three standard underestimate the measured capacities no matter which interpreted capacities is considered as failure load, while ISO makes slightly overprediction at the lower range of eccentricities and underprediction at higher range of eccentricities for some cases. In the inclined loading condition, the prediction by API RP2GEO is minimum among the three standards, while ISO proposed the highest prediction. All three prediction underestimate the capacity under inclined loading condition. From this study, it is found that small scale load laboratory test reveals a qualitative understanding with impact of vertical eccentric and concentric inclined loading on ultimate capacities. However, it is hard to detect a clear best prediction based on small scaled laboratory load test results. The well-controlled field test results, especially the field tests with vertical eccentric and concentric inclined loading condition, are valuable to evaluate the consistency of predicted capacity by three standards. / text

This report attempts to assess the degree to which China is developing a framework that supports domestic innovative capacity. This framework is not a predefined set of components, but is instead a combination of political, institutional, market, and technology factors and linkages that support information flows, interactions between entities, and incentives necessary to increase domestic innovation. Literature suggests that factors contributing to this framework may be influenced by domestic policy, and this report attempts to identify Chinese policies that contribute to the development of this framework within the Chinese solar photovoltaic (PV) and automotive industries. This report uses patent and export data as proxies for innovation in these two industries to measure the presence of this framework. The data suggest that the framework supporting domestic innovation in China is further developed for the solar PV industry than the automotive industry, but that the solar PV industry is still far from leading global innovation. Finally, the report identifies potential factors that have contributed to the variations between these two industries, and challenges that both industries may face in the near future. / text

ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CA / In this work we evaluated the performance of different water filling algorithms. We have selected four power allocation algorithms: Conventional water-filling (CWF), Constant power water-filling, Inverse Water-filling (IWF), and Adaptive Iterative Water-Filling (AIWF) algorithms. Capacity is the performance metric we used to compare the above algorithms by taking the optimality of transmission power allocation to each sub-channel into account. The power allocation can be calculated with a reference of the water level value that has different approaches for different algorithms. The water level can either be fixed once it is found, or it may be adaptive or different for different sub-channels. Hence, the results show that the adaptive iterative water filling (AIWF) algorithm has a better effect on the performance of MIMO-OFDM system by allocating power adaptively.

The study examines the potential for extensive connection of photovoltaic (PV) production in the Swedish rural power grid, considering the case distribution grid (10kV) of Herrljunga Elektriska. Hourly PV production is calculated using radiation and temperature data together with information regarding building roofs in the studied area. Furthermore, hourly customer load data is aggregated, enabling detailed power flow simulations of the grid resulting in hourly voltages and currents for all nodes during 2014. Three cases with varying PV production are studied, using different thresholds for minimum annual radiation. Thus, roofs with lower annual radiation are excluded from the simulations, limiting PV production. The three cases considers annual radiation greater than 0 kWh/m2 , 700 kWh/m2 and 1000 kWh/m2. Simulations show that the distribution grid in Herrljunga maintains acceptable performance with respect to voltages and currents for the 1000 kWh/m2,year case, yielding an annual production of 30 % of consumption. The hosting capacity, which is an estimate of the amount of PV that can be connected to the grid, is therefore 30 %. In order to further examine grid limitations, weak parts of the grid are identified. These are situated in the peripheral parts of the grid, which is in accordance with earlier studies of intermittent power production in distribution grids. Additionally, low voltage grids in connection to these weaker parts of the distribution grid are simulated, showing no further limitations for hosting capacity.