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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.
231

Bayesian Information Fusion for Precision Indoor Location

Cavanaugh, Andrew F 07 February 2011 (has links)
This thesis documents work which is part of the ongoing effort by the Worcester Polytechnic Institute (WPI) Precision Personnel Locator (PPL) project, to track and locate first responders in urban/indoor settings. Specifically, the project intends to produce a system which can accurately determine the floor that a person is on, as well as where on the floor that person is, with sub-meter accuracy. The system must be portable, rugged, fast to set up, and require no pre-installed infrastructure. Several recent advances have enabled us to get closer to meeting these goals: The development of Transactional Array Reconciliation Tomography(TART) algorithm, and corresponding locator hardware, as well as the integration of barometric sensors, and a new antenna deployment scheme. To fully utilize these new capabilities, a Bayesian Fusion algorithm has been designed. The goal of this thesis is to present the necessary methods for incorporating diverse sources of information, in a constructive manner, to improve the performance of the PPL system. While the conceptual methods presented within are meant to be general, the experimental results will focus on the fusion of barometric height estimates and RF data. These information sources will be processed with our existing Singular Value Array Reconciliation Tomography (σART), and the new TART algorithm, using a Bayesian Fusion algorithm to more accurately estimate indoor locations.
232

Energy new towns : a look at population and socioeconomic problems and solutions

McCoy, Hugh A January 2010 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
233

Location problems in the presence of queueing

Chiu, Samuel Shin-Wai January 1982 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Alfred P. Sloan School of Management, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND DEWEY. / Bibliography: leaves 184-189. / by Samuel Shin-Wai Chiu. / Ph.D.
234

Prediction and influence maximization in location-based social networks.

January 2012 (has links)
基于地理位置的社交网络近年得到了非常多的关注。为了提升用戶粘性和吸引用戶,社交問路提供商会提供給用戶基于地理信息的广告和优惠券等服务。方了让广告和优惠券的投递更有效, 预测用戶下个可能访问的地点变得尤为重要。但是,预测地点一个不可避免的挑战就是數一百万计的候选地点构成了庞大的預測空间,使得整个预测过程变成复杂且缓慢。在本论文中,我們利用用戶签到的类別信息对潜在的用戶运动模式進行了建模并提出了一个混合隐马尔可夫模型去预测用戶下个可能访问的地点类别。基于预测出的类别,我們继而对用戶可能访问的地点进行了預測。在类別层次进行建模的好处是能有效地減少候选地点的个數并且能准确地描述用戶行动的实际意义。一般来說,用戶的行为会受到令人偏好的影响,基于这个現象,我們还运用分类的方法对用戶根据其令人愛好的不同進行了划分并对每个组群制定各自的隐马尔可夫模型。实验結果表示如果先预测用可能访问的地点类别,能使得地点预测空间极大地减少预测精度也会变高。 / 在预测用可能访问的地点之后,另外一个很重要的问题是选择将优惠券投递给哪些用从而将产品或地点的影响最大化。在实际运用中,这种将影响最大化的算法会遇到速度上的壁垒。在本论文中,我们研究了在基于地理位置的社交网络中的影响最大化问题,并提出了一个分割方法能有效地提升算法的运行速度。实验结果显示我们的算法在于业界标准方法达到几乎一致的影响力的前提下,能更快地运行。 / Location-based social networks have been gaining increasing popularity in recent years. To increase users’ engagement with location-based services, it is important to provide attractive features, one of which is geo-targeted ads and coupons. To make ads and coupons delivery more effective, it is essential to predict the location that is most likely to be visited by a user at the next step. However, an inherent challenge in location prediction is a huge prediction space, with millions of distinct check-in locations as prediction target. In this thesis we exploit the check-in category information to model the underlying user movement pattern. We propose a framework which uses a mixed hidden Markov model to predict the category of user activity at the next step and then predicts the most likely location given the estimated category distribution. The advantages of modeling on the category level include a significantly reduced prediction space and a precise expression of the semantic meaning of user activities. In addition, as user check-in behaviors are heavily influenced by their preferences, we take a clustering approach to group users with similar preferences, and train a separate hidden Markov model for each group. Extensive experimental results show that, with the predicted category distribution, the number of location candidates for prediction is much smaller, while the location prediction accuracy becomes higher. / Choosing the right users to deliver the coupons and maximizing the influence spread is also an important problem in LBSN, which is called influence maximization problem. In practice speed is an important issue to solve the influence maximization problem. In this thesis, we study the influence maximization problem in location-based social networks and propose a scalable partition approach to solve the influence maximization problem efficiently. Experimental results show that our partition approach achieves quite similar influence spread performance with the original influence maximization approach, while running much faster. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zhu, Zhe. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 93-101). / Abstracts also in Chinese. / Abstract --- p.i / Acknowledgement --- p.vi / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background Study --- p.11 / Chapter 2.1 --- Location prediction --- p.11 / Chapter 2.2 --- Influence maximization --- p.16 / Chapter 3 --- User Activity and Location Prediction in Location-based Social Networks --- p.20 / Chapter 3.1 --- Data Analysis --- p.20 / Chapter 3.1.1 --- Data Collection --- p.21 / Chapter 3.1.2 --- Dataset Properties --- p.22 / Chapter 3.2 --- User Activity Prediction --- p.26 / Chapter 3.2.1 --- Definitions --- p.27 / Chapter 3.2.2 --- Category Prediction based on HMM --- p.28 / Chapter 3.2.3 --- Mixed HMM with Temporal and Spatial Covariates --- p.34 / Chapter 3.2.4 --- User Preference Modeling --- p.41 / Chapter 3.3 --- Location Prediction --- p.43 / Chapter 3.4 --- Experimental Evaluation --- p.45 / Chapter 3.4.1 --- Data Preparation --- p.46 / Chapter 3.4.2 --- Category Prediction --- p.47 / Chapter 3.4.3 --- Location Prediction --- p.51 / Chapter 3.5 --- Summary --- p.58 / Chapter 4 --- A Partition Approach to Scalable Influence Maximization in Location-based Social Networks --- p.60 / Chapter 4.1 --- Problem definition --- p.60 / Chapter 4.2 --- Influence probability --- p.62 / Chapter 4.2.1 --- Base model --- p.62 / Chapter 4.2.2 --- Distance and similarity model --- p.65 / Chapter 4.2.3 --- Location entropy model --- p.72 / Chapter 4.3 --- Partition approach --- p.74 / Chapter 4.4 --- Evaluation --- p.79 / Chapter 4.4.1 --- Data preparation --- p.79 / Chapter 4.4.2 --- Precision evaluation --- p.80 / Chapter 4.4.3 --- Influence spread evaluation --- p.83 / Chapter 4.4.4 --- Running time --- p.86 / Chapter 4.5 --- Summary --- p.88 / Chapter 5 --- Conclusion --- p.90 / Bibliography --- p.93
235

ANDROID AND WEB APPLICATION FOR TRACKING EMPLOYEES

Dholakia, Kaival 01 December 2019 (has links)
The purpose that this tracking system serves is to keep track of the employees of the company who have the nature of their job which involves a lot of traveling to various locations on a day to day basis. It is an amalgamation of Android as well as a Web application. The employee is supposed to pass the location and image as per the terms and conditions specified to use the Android application. The web application is used by the admin department to access the information which would help them monitor the location of the employee in a timely manner. The Android application is developed using Native Android on Android Studio while Visual Studio 2017 is being used for the functioning of the web application.
236

Location tracking architectures for wireless VoIP

Shah, Zawar, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 2009 (has links)
A research area that has recently gained great interest is the development of network architectures relating to the tracking of wireless VoIP devices. This is particularly so for architectures based on the popular Session Initiation Protocol (SIP). Previous work, however, in this area does not consider the impact of combined VoIP and tracking on the capacity and call set-up time of the architectures. Previous work also assumes that location information is always available from sources such as GPS, a scenario that rarely is found in practice. The inclusion of multiple positioning systems in tracking architectures has not been hitherto explored. It is the purpose of this thesis to design and test SIP-based architectures that address these key issues. Our first main contribution is the development of a tracking-only SIP based architecture. This architecture is designed for intermittent GPS availability, with wireless network tracking as the back-up positioning technology. Such a combined tracking system is more conducive with deployment in real-world environments. Our second main contribution is the development of SIP based tracking architectures that are specifically aimed at mobile wireless VoIP systems. A key aspect we investigate is the quantification of the capacity constraints imposed on VoIP-tracking architectures. We identify such capacity limits in terms of SIP call setup time and VoIP QoS metrics, and determine these limits through experimental measurement and theoretical analyses. Our third main contribution is the development of a novel SIP based location tracking architecture in which the VoIP application is modified. The key aspect of this architecture is the factor of two increase in capacity that it can accommodate relative to architectures utilizing standard VoIP. An important aspect of all our tracking architectures is the Tracking Server. This server supplies the location information in the event of GPS unavailability. A final contribution of this thesis is the development of novel particle-filter based tracking algorithms that specifically address the GPS intermittency issue. We show how these filters interact with other features of our SIP based architectures in a seamless fashion.
237

桃園縣產業多元化之趨勢對航空城發展之意涵 / Industrial diversification of taoyuan county for aerotroplis development

李佩諦 Unknown Date (has links)
This paper studies the industrial structure and degree of industrial diversification of Taoyuan County since 1986 to examine if Taoyuan Aerotroplis will meet one of the successful key factors of industrial diversification. It begins with a discussion of strategic analysis on critical factors of Taoyuan International Airport and finds out one of the important factors of successful aerotroplis lies in industrial diversification. This research is conducted by adopting quantitative approach and applying coefficient of industry diversity to value the degree. The Location Quotients (LQs) ratios are applied as well, providing a way to examine the specialization of economic activity in Taoyuan County. The finding reveals that the industrial structure of Taoyuan County is secondary industry from 1986 to 1991. After 1991, the tertiary industry grows enormously and now it trends to service-oriented market. Also, industrial diversification of Taoyuan County is toward positive and high degree of diversity in industry since 1986. Taoyuan County has a relatively higher concentration of employment in manufacturing than Taiwan since 1986. Health Care Services industry, Water Supply and Remediation Services industry and Transportation, Storage and Communication industry are industries which increase concentration of employment in Taoyuan County. This research suggests that the authority concerned could make use of the positive condition of diversity in industry to accelerate industrial cluster in development of aerotroplis that strengthen the competitiveness of Taoyuan Airport and attract more cargo and passengers traffic. Further research is suggested by enlarging the areas such as Taipei County development axis or Hsinchu County, by broadening the sample of the industry scope and classification systems to subsectors, industry group or industry and by comparing the industrial diversification of Taoyuan Aerotroplis with that of the other countries which succeeds in aerotroplis models.
238

A voltage-only method for estimating the location of transmission faults

Vatani, Mehrdad, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
239

Essays on market structure, location and growth

Minniti, Antonio 30 August 2007 (has links)
This dissertation collects essays that focuses on two branches of the economic literature on imperfect competition: the one of IO on the decision of firms' location and the one of economic growth on market structure and technological progress. Chapter 2 deals with the issue of firms' location and proposes a model that sheds light on how the geographic distribution of firms is affected by strategic interaction in presence of vertically differentiated products. The remaining Chapters, instead, have a common root; they, in fact, deal with the link existing between market structure and growth. More precisely, Chapter 3 studies how knowledge spillovers across firms influence this link and introduces the basic framework which is further extended in Chapters 4 and 5 to allow for strategic interaction and multi-product firms respectively. In all these models technological progress takes the form of cost reductions. The model-setting considered in these Chapters belongs to the class of creative accumulation models, whose introduction in the economic literature is relatively recent and can be attributed to Smulders and van de Klundert and Peretto. Finally, Chapter 6 follows the creative destruction tradition initiated by Grossman and Helpman and Aghion and Howitt and develops a growth model with product quality innovations of random size. In all the Chapters of this dissertation, we adopt a normative perspective by comparing the market equilibrium solution to the optimal one.
240

Return on Investment Analysis for Facility Location

Myung, Young-soo, Tcha, Dong-wan 05 1900 (has links)
We consider how the optimal decision can be made if the optimality criterion of maximizing profit changes to that of maximizing return on investment for the general uncapacitated facility location problem. We show that the inherent structure of the proposed model can be exploited to make a significant computational reduction.

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