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Implementação de um localizador de faltas híbrido para linhas de transmissão com três terminais baseado na transformada wavelet; Implementation of a hybrid fault location for tree-terminals transmission lines based in wavelet transform

Silva, Murilo da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 15/02/2008 PT
Relevância na Pesquisa
36.34%
Este trabalho apresenta o estudo e o desenvolvimento de um algoritmo híbrido para detecção, classificação e localização de faltas em sistemas com três terminais utilizando como principal ferramenta a transformada wavelet (TW) em suas versões discreta (TWD) e estacionária (TWE). O algoritmo é dito híbrido, pois alia duas metodologias para localizar a falta. A primeira baseada na análise de componentes de alta freqüência (ondas viajantes) e a segunda, baseada na extração dos componentes fundamentais para o cálculo da impedância aparente. A metodologia proposta foi concebida de maneira a trabalhar com dados sincronizados dos três terminais ou apenas dados locais para estimar a localização da falta. O localizador híbrido escolhe automaticamente qual a melhor técnica de localização ser utilizada para alcançar uma localização confiável e precisa. Deste modo, um método pode suprir as dificuldades do outro, ou, no mínimo, fornecer mais informações para que, junto ao conhecimento do operador, uma localização próxima da ótima possa ser alcançada. Com o objetivo de testar e validar a aplicabilidade do algoritmo de localização de faltas híbrido para linhas com três terminais, utilizou-se de dados de sinais faltosos obtidos através de simulações do software ATP (Altenative Transients Program)...

Localização de faltas em linhas de transmissão com derivações, constituídas por circuito duplo e trechos não transpostos.; Fault location on transmission lines with derivations, constituted of double circuit and untransposed sections.

Di Santo, Silvio Giuseppe
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 13/12/2012 PT
Relevância na Pesquisa
36.34%
Neste trabalho foi desenvolvido um método de localização de faltas em linhas de transmissão constituídas de circuitos simples ou duplos, admitindo trechos não transpostos e com derivações, além de terminais com medições dessincronizadas. O método utiliza os fasores de tensão e corrente, pré-falta e pós-falta, medidos nos terminais, local e remoto, para determinar as informações da falta, as quais são: trecho de ocorrência, distância, resistência e tipo. O método de localização de faltas proposto neste trabalho é composto pelo: processo de obtenção dos fasores, onde os sinais de tensão e corrente são filtrados; algoritmo de montagem da matriz de admitâncias da rede; algoritmo de estimativa de cargas e algoritmo de localização de faltas. O método desenvolvido tem como principal característica a localização de faltas em linhas de transmissão constituídas por circuito duplo com derivações utilizando dados de somente dois terminais, não descartando a possibilidade da utilização de dados de outros terminais caso disponíveis, e a pesquisa por trechos da rede através da minimização de funções objetivo. Para avaliar a eficiência do método de localização de faltas desenvolvido, diversas simulações foram realizadas no programa ATP (Alternative Transient Program)...

Errors due to the tropospheric and ionospheric effects on the geographic location of data collection platforms

Celestino, Claudia Celeste; Sousa, Cristina Tobler de; Kuga, Helio Koiti; Yamaguti, Wilson
Fonte: Sociedade Brasileira de Geofísica Publicador: Sociedade Brasileira de Geofísica
Tipo: Artigo de Revista Científica Formato: 427-436
ENG
Relevância na Pesquisa
36.34%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); O uso de medidas do desvio Doppler para localizar um transmissor foi estudado e testado considerando o Sistema Brasileiro de Coleta de Dados Ambientais. Para melhorar a localização de plataformas de coleta de dados (PCDs), com os seus transmissores, alguns efeitos como a correção devido a ionosfera e atroposfera, foram considerados no trabalho de Celestino et al. (2007) usando dados simulados e algumas avaliações dos erros iniciais de uma única PCD. Este trabalho apresenta uma avaliação dos impactos sobre a localização geográfica, devido aos efeitos da ionosfera e da troposfera, entretanto usando duas PCDs meteorológicas e cobrindo um periodo mais longo de testes (um ano). Os efeitos, sazonal e dia-noite, também são analisados durante este periodo experimental. Os resultados das análises indicam que a correção dos efeitos da ionosfera e da troposfera pode, em media, reduzir os erros de localização a escala entre dez e cem metros para as condições de testes independente da localização da PCD que foi utilizada. Devido a complexidade da modelagem das fontes dos erros na localização de uma plataforma...

The around architecture for dynamic location-based services

José, Rui; Moreira, Adriano; Rodrigues, Helena; Davies, Nigel
Fonte: Kluwer Academic Publishers Publicador: Kluwer Academic Publishers
Tipo: Artigo de Revista Científica
Publicado em /08/2003 ENG
Relevância na Pesquisa
36.42%
This paper presents a generic concept of location-based service as an abstraction for supporting the association between computational resources and location. The objective is to extend the advantages of service-based architectures to the development of location-based systems, thus providing a more open and extensible alternative to the “vertical” approaches typically used in this type of system. The novel AROUND architecture is proposed as an approach for supporting location-based services in the Internet environment. AROUND provides a service location infrastructure that allows applications to select services that are specifically associated with their current location. The architecture includes a flexible scope model that defines the association between services and location, and a service location infrastructure organised by spatial criteria and optimised for location-based queries. Based on a prototype implementation of this architecture, we have developed two case studies that illustrate the use of this approach for developing location-based systems. The overall results provide a valuable insight into the applicability of the architecture, and suggest that this model of location-based services can provide a useful approach for the development of a wide range of location-based applications.

Unified cooperative location system

Navalho, David Precatado
Fonte: FCT- UNL Publicador: FCT- UNL
Tipo: Dissertação de Mestrado
Publicado em //2009 ENG
Relevância na Pesquisa
36.41%
Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do Grau de Mestre em Engenharia Informática.; The widespread use of smaller, less expensive, and more capable mobile devices, has opened the door for more complex and varied mobile computing applications. Additionally, manufacturers are increasingly equipping these handheld devices with every type of wireless connectivity and sensors that can be explored for providing more complex services. In recent years, several techniques for location estimation have been developed, providing different degrees of accuracy. Some of these solutions require the installation of specific hardware in the environment, while others explore the existing infrastructure. In particular, it is possible to explore the existing communication infrastructure to build a location system relying on signal strength measures. However, while several systems already exist to locate users based on different approaches, there is no single one that is good for every situation while providing high accuracy, low cost and ubiquitous coverage. Not only that, but very few research has been made regarding on how a group of users can cooperate to improve accuracy or reduce energy consumption while using the location system. This work presents the Unified Cooperative Location System...

Location-based Marketing: the academic framework

Buczkowski, Aleksander
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 01/03/2012 ENG
Relevância na Pesquisa
36.45%
Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.; Over the last several years one could observe revolution in location-based technologies and geospatial information. Location awareness of mobile devices resulted in development of Location-Based Services (LBS) that are realization of that revolution in the most personal and contextual way. The ability to reach consumers in the highly targeted manner based on spatio-temporal criteria, attracted marketers from the early beginning of LBS creating field called Location-Based Marketing. Today decreasing prices of smartphones and wireless internet, as well as integration of location-aware mobile solutions and social media is leading to new possibilities and opportunities. The academic and professional interests of the author made him noticed that although the industry has challenged a significant development, there is lack of publications that would put an academic framework on that progress. The research has fulfilled this gap by extensive investigation of the current state of the art of Location-Based Marketing and its foundations - Location Based Services. The dissertation provides academic framework by comprehensive analysis of the Location-Based Marketing from LBS and marketing perspective. Further the thesis is addressing the issue of significant discrepancy between theoretical concepts of measurable Location-Based Social Media data and the actual data than can be legally accessed and used for marketing analysis purposes by investigation a case study of Location-Based Social Network - Foursqaure and Location-Based Analytics platform VenueLabs.

Uncapacitated facility location problems: contributions

Galvão,Roberto Diéguez
Fonte: Sociedade Brasileira de Pesquisa Operacional Publicador: Sociedade Brasileira de Pesquisa Operacional
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2004 EN
Relevância na Pesquisa
36.39%
The objective of the present paper is to review my personal contributions in the field of uncapacitated facility location problems. These contributions took place throughout my academic career, from the time I was a Ph.D. student at Imperial College to the present day. They cover approximately 30 years, from 1973 to 2003; they address: algorithms developed for the p-median problem and for a general formulation of uncapacitated location problems; the study of dynamic location models; covering and hierarchical location problems; queuing-based probabilistic location models. The contributions encompass theoretical developments, computational algorithms and practical applications. All work took place in an academic environment, with the invaluable collaboration of colleagues (both in Brazil and abroad) and research students at COPPE. Each section in the paper is dedicated to a topic that involves a personal contribution. Every one of them is placed within the context of the existing literature.

Dynamic Hashing + Quorum = Efficient Location Management for Mobile Computing Systems

Singhal, Mukesh ; Prakash, Ravi
Fonte: University of Rochester. Computer Science Department. Publicador: University of Rochester. Computer Science Department.
Tipo: Relatório
ENG
Relevância na Pesquisa
36.47%
Location management is a fundamental problem in mobile computing systems. Existing industry standards employ centralized location management schemes. Centralized schemes are not highly scalable. This paper presents a new, distributed location management strategy for mobile systems. Its salient features are fast location update and query, load balancing among location servers, and scalability. The strategy employs dynamic hashing techniques and quorums to manage location update and query operations. Location information of a mobile host is replicated at a subset of location servers. The set of location servers associated with a mobile host changes with time, depending on the location of mobile hosts and load on the servers. This dynamism prevents situations of heavy load (location update and query messages) on some location servers when the mobile hosts are not uniformly distributed in space, or when some mobile hosts have their location updated or queried more often than others. New location servers can be added to the system as the number of mobile hosts and/or location update and query rates increase. Also, if the load diminishes, the number of location servers in the system can be reduced. Tries and quorum systems are used to expand and shrink the number of location servers. Unlike several existing schemes that progressively expand their region of search and may require multiple rounds of messages to locate a mobile host...

Localização de faltas em linhas de transmissão usando morfologia matemática; Location of Fault Lines Transmission using Mathematical Morphology

Cavalcante, Paulo Anderson Holanda
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Elétrica; Automação e Sistemas; Engenharia de Computação; Telecomunicações Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Elétrica; Automação e Sistemas; Engenharia de Computação; Telecomunicações
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
36.36%
This work an algorithm for fault location is proposed. It contains the following functions: fault detection, fault classification and fault location. Mathematical Morphology is used to process currents obtained in the monitored terminals. Unlike Fourier and Wavelet transforms that are usually applied to fault location, the Mathematical Morphology is a non-linear operation that uses only basic operation (sum, subtraction, maximum and minimum). Thus, Mathematical Morphology is computationally very efficient. For detection and classification functions, the Morphological Wavelet was used. On fault location module the Multiresolution Morphological Gradient was used to detect the traveling waves and their polarities. Hence, recorded the arrival in the two first traveling waves incident at the measured terminal and knowing the velocity of propagation, pinpoint the fault location can be estimated. The algorithm was applied in a 440 kV power transmission system, simulated on ATP. Several fault conditions where studied and the following parameters were evaluated: fault location, fault type, fault resistance, fault inception angle, noise level and sampling rate. The results show that the application of Mathematical Morphology in faults location is very promising; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; Neste trabalho...

Resource, Strategies, Location Determinants, And Host Country Location Choice By Emerging Market Firms

Jain, Naveen K
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
36.38%
The extant literature had studied the determinants of the firms’ location decisions with help of host country characteristics and distances between home and host countries. Firm resources and its internationalization strategies had found limited attention in this literature. To address this gap, the research question in this dissertation was whether and how firms’ resources and internationalization strategies impacted the international location decisions of emerging market firms. To explore the research question, data were hand-collected from Indian software firms on their location decisions taken between April 2000 and March 2009. To analyze the multi-level longitudinal dataset, hierarchical linear modeling was used. The results showed that the internationalization strategies, namely market-seeking or labor-seeking had direct impact on firms’ location decision. This direct relationship was moderated by firm resource which, in case of Indian software firms, was the appraisal at CMMI level-5. Indian software firms located in developed countries with a market-seeking strategy and in emerging markets with a labor-seeking strategy. However, software firms with resource such as CMMI level-5 appraisal, when in a labor-seeking mode...

Global sensitivity analysis of fault location algorithms.

Ooi, Hoong Boon
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2009
Relevância na Pesquisa
36.42%
Transmission lines of any voltage level are subject to faults. To speed up repairs and restoration of power, it is important to know where the fault is located. A fault location algorithm’s result is influenced by a series of modeling equations, setting parameters and system factors reflected in voltage and current inputs. The factors mentioned are subject to sources of uncertainty including measurement and signal processing errors, setting errors and incomplete modeling of a system under fault conditions. These errors have affected the accuracy of the distance to fault calculation. Accurate fault location reduces operating costs by avoiding lengthy and expensive patrols. Accurate fault location speeds up repairs and restoration of lines, ultimately reducing revenue loss caused by outages. In this thesis, we have reviewed the fault location algorithms and also how the uncertainty affects the results of fault location. Sensitivity analysis is able to analyze how the variation in the output of the fault location algorithms can be allocated to the variation of uncertain factors. In this research, we have used global sensitivity analysis to determine the most contributed uncertain factors and also the interaction of the uncertain factors. We have chosen Analysis of Variance (ANOVA) decomposition as our global sensitivity analysis. ANOVA decomposition shows us the insight of the fault location...

Exploration and analysis of sensor technologies for efficient indoor location-based services; Erfoschung und Analyse von Senortechnologien fuer die Implementierung effizienter Dienste zur Positionsbestimmung innerhalb Gebaeuden

Subramanian, Ponmalar Suguna
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
Relevância na Pesquisa
36.41%
In recent years, there is a mounting obligation for indoor location based services Comparable to outdoor location based services . Indoor guidance systems provide ample utilities to a user explicitly huge complex at shopping malls , hospitals and at vast libraries for any directed assistance. Pedestrian navigation is one such promising indoor location based service. Localization remains a basis for all location based services . Although, few pedestrian -based indoor localization are systems available in market , they lack either one of the attributes as such accuracy, reliability, scalability and / or expensive. GPS is not meant for indoors and even if so used at indoors , its relatively weak signal still stay a hurdle for any indoor location based services . In this dissertation , the aim is to build an efficient and precise indoor localization approach that can be implemented for most of the large indoor environments. The projected approach in this study incomparable to GPS that works outdoors will, remain eminently than other available indoor localization based approaches. All prerequisite for efficient localization such as accuracy, reliability, scalability, flexibility, availability, cost efficiency , minimum latency and robustness were evaluated reconstructed for this approach that is herewith demonstrated in my dissertation. The dissertation is structured as various chapters . Each of the chapter in this dissertation portrays novel methods utilizing major sensor technologies such as Bluetooth...

On The Problem of Simultaneous Encoding of Magnitude and Location Information

Castro, Rui; Wakin, Michael; Orchard, Michael; Castro, Rui; Wakin, Michael; Orchard, Michael
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Conference paper; Text; Text
ENG
Relevância na Pesquisa
36.38%
Conference Paper; Modern image coders balance bitrate used for encoding the location of signicant transform coefficients, and bitrate used for coding their values. The importance of balancing location and value information in practical coders raises fundamental open questions about how to code even simple processes with joint uncertainty in coefficient location and magnitude. This paper studies the most basic example of such a process: a 2-D process studied earlier by Weidmann and Vetterli that combines Gaussian magnitude information with Bernoulli location uncertainty. The paper offers insight into the coding of this process by investigating several new coding strategies based on more general approaches to lossy compression of location. Extending these ideas to practical coding, we develop a trellis-coded quantization algorithm with performance matching the published theoretical bounds. Finally, we evaluate the quality of our strategies by deriving a rate-distortion bound using Blahut's algorithm for discrete sources.

The use of ambient audio to increase safety and immersion in location-based games

KURCZAK, JOHN JASON
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
36.38%
The purpose of this thesis is to propose an alternative type of interface for mobile software being used while walking or running. Our work addresses the problem of visual user interfaces for mobile software be- ing potentially unsafe for pedestrians, and not being very immersive when used for location-based games. In addition, location-based games and applications can be dif- ficult to develop when directly interfacing with the sensors used to track the user’s location. These problems need to be addressed because portable computing devices are be- coming a popular tool for navigation, playing games, and accessing the internet while walking. This poses a safety problem for mobile users, who may be paying too much attention to their device to notice and react to hazards in their environment. The difficulty of developing location-based games and other location-aware applications may significantly hinder the prevalence of applications that explore new interaction techniques for ubiquitous computing. We created the TREC toolkit to address the issues with tracking sensors while developing location-based games and applications. We have developed functional location-based applications with TREC to demonstrate the amount of work that can be saved by using this toolkit.In order to have a safer and more immersive alternative to visual interfaces...

Wireless privacy and personalized location-based services: the challenge of translating the legal framework into business practices

Gratton, Eloïse
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
EN
Relevância na Pesquisa
36.38%
L'avancement des communications sans-fil permet l'obtention de nouveaux services bases sur l'habileté des fournisseurs de services sans-fil à déterminer avec précision, et avec l'utilisation de technologies de pistage, la localisation et position géographiquement d'appareils sans-fil Cette habileté permet d'offrir aux utilisateurs de sans-fil de nouveaux services bases sur la localisation et la position géographique de leur appareil. Le développement des services basés sur la localisation des utilisateurs de sans-fil soulevé certains problèmes relatifs à la protection de la vie privée qui doivent être considérés. En effet, l'appareil sans-fil qui suit et enregistre les mouvements de I 'utilisateur permet un système qui enregistre et entrepose tous les mouvements et activités d'un tel utilisateur ou encore qui permet l'envoi de messages non anticipes à ce dernier. Pour ce motif et afin de protéger la vie privée des utilisateurs de sans-fil, une compagnie désirant développer ou déployer une technologie permettant d'offrir ce genre de services personnalisés devra analyser l'encadrement légal touchant la protection des données personnelles--lequel est dans certains cas vague et non approprié à ce nouveau contexte--ainsi que la position de l'industrie dans ce domaine...

How do I design a location-dependent application?

Meneses, Filipe; Moreira, Adriano; José, Rui
Fonte: SPIE. The International Society for Optical Engineering Publicador: SPIE. The International Society for Optical Engineering
Tipo: Conferência ou Objeto de Conferência
Publicado em /08/2001 ENG
Relevância na Pesquisa
36.42%
The generalisation of the Internet and the recent technological developments in embedded systems and wireless networks contribute to the realisation of a vision where access to information is possible at any moment and from anywhere. This is particularly attractive with information that is relevant to a specific geographic location. Applications that rely on location-based services to provide information to mobile users, or that support interaction with real devices in the user neighbourhood, are called location-dependent applications and enhance the relationship between mobile users and a specific geographic location. However, the design of such applications breaks with the existing paradigms and methodologies as the mobile devices and the wireless communication infrastructures have characteristics that are very different from those of desktop computers and wired communication systems. The Around architecture is an open and extensible framework for location-based services that allows network services to be associated with specific geographic locations. By using this architecture applications can select services that are relevant for specific locations. Within the context of the Around project we have developed a prototype system with multiple location-based services and an application that accesses these services to provide information related to a town transportation system. This paper reports on the design and development of this location-based application. Its design raised several new issues...

Securing location discovery in wireless sensor networks

Kadhim, Wisam F.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
36.38%
Providing security for wireless sensor networks in hostile environments has a significant importance. Resilience against malicious attacks during the process of location discovery has an increasing need. There are many applications that rely on sensor nodes' locations to be accurate in order to function correctly. The need to provide secure, attack resistant location discovery schemes has become a challenging research topic. In this thesis, location discovery techniques are discussed and the security threats and attacks are explained. I also present current secure location discovery schemes which are developed for range-based location discovery. The thesis goal is to develop a secure range-free location discovery scheme. This is accomplished by enhancing the voting-based scheme developed in [8, 9] to be used as the bases for developing a secure range-free location discovery scheme. Both the enhancement voting-based and the secure range-free schemes are implemented on Sun SPOT wireless sensors and subjected to various levels of location discovery attacks and tested under different sensor network scales using a simulation program developed for testing purposes.

Multicriteria approach for service units location: proposal of method SMARTER application; Multicriteria approach for service units location: proposal of method SMARTER application; Enfoque multicritério para a localização de instalações de serviço: aplicação do método SMARTER

Lopes, Yuri Gama; UFPE; De Almeida, Adiel Teixeira; UFPE
Fonte: Universidade Federal Fluminense - LATEC Publicador: Universidade Federal Fluminense - LATEC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; Formato: application/pdf
Publicado em 29/05/2009 POR
Relevância na Pesquisa
36.38%
Among the various types of decision present during the planning and business management process, location decision is a critical factor to organization development, as much in their own business activities, as in the company performance in the supply chain in which it is included, which involves its customers satisfaction, logistics costs and operational results. Particularly, the location of service units of involves a greater amount of subjective factors, hampering the use of traditional decision models to tackle the location problem. Such models, in their majority, have methodological problems in its analysis and calculus procedures, especially in the decision-maker preferences structuring and in the mullticriteria agreggation procedures. This paper seeks structure methodologically the multicriteria decision making to locate service units. For this, it is proposed the use of the method SMARTER (Simple Multi-Attribute Rating Technique using Exploiting Rankings), and a numerical application is described.; Among the various types of decision present during the planning and business management process, location decision is a critical factor to organization development, as much in their own business activities, as in the company performance in the supply chain in which it is included...

Anonymizing but Deteriorating Location Databases

Khanh Dang,Tran; Anh Truong,Tuan
Fonte: Instituto Politécnico Nacional, Centro de Innovación y Desarrollo Tecnológico en Cómputo Publicador: Instituto Politécnico Nacional, Centro de Innovación y Desarrollo Tecnológico en Cómputo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
Relevância na Pesquisa
36.36%
The tremendous development of location-based services and mobile devices has led to an increase in location databases. Through the data mining process, valuable information can be discovered from such location databases. However, the malicious data miner or attackers may also extract private and sensitive information about the user, and this can create threats against the user location privacy. Therefore, location privacy protection becomes a key factor to the success in privacy protection for the users of location-based services. In this paper, we propose a novel approach as well as an algorithm to guarantee k-anonymity in a location database. The algorithm will maintain the association rules that have significance for the data mining process. Moreover, there may appear new significant association rules created after anonymization, they maybe affect the data mining result. Therefore, the algorithm also considers excluding new significant association rules that are created during the run of the algorithm. Theoretical analyses and experimental results with real-world datasets will confirm the practical value of our newly proposed approach.

A Positioning Scheme Combining Location Tracking with Vision Assisting for Wireless Sensor Networks

Tsai,F.; Chiou,Y.-S.; Chang,H.
Fonte: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico Publicador: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2013 EN
Relevância na Pesquisa
36.36%
This paper presents the performance of an adaptive location-estimation technique combining Kalman filtering (KF) with vision assisting for wireless sensor networks. For improving the accuracy of a location estimator, a KF procedure is employed at a mobile terminal to filter variations of the location estimate. Furthermore, using a vision-assisted calibration technique, the proposed approach based on the normalized cross-correlation scheme is an accuracy enhancement procedure that effectively removes system errors causing uncertainty in real dynamic environments. Namely, according to the vision-assisted approach to extract the locations of the reference nodes as landmarks, a KF-based approach with the landmark information can calibrate the location estimation and reduce the corner effect of a location-estimation system. In terms of the location accuracy estimated from the proposed approach, the experimental results demonstrate that more than 60 percent of the location estimates have error distances less than 1.4 meters in a ZigBee positioning platform. As compared with the non-tracking algorithm and non-vision-assisted approach, the proposed algorithm can achieve reasonably good performance.