• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 42
  • 17
  • 7
  • 5
  • 4
  • 4
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 115
  • 16
  • 16
  • 15
  • 14
  • 12
  • 12
  • 11
  • 11
  • 9
  • 9
  • 9
  • 8
  • 8
  • 8
  • 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.
31

Distribuce místně závislých informací v mobilních aplikacích / Distribution of Location-Based Information in Mobile Applications

Bátrla, Tomáš January 2007 (has links)
Master thesis is focused on retrieval of multimedia information based on location of mobile device. Paper describes mobile platforms technology and technology behind location sensing and two-dimensional barcode recognition. There is also included design of client-server architecture for information retrieval of location based multimedia data. Master thesis includes report of system testing and some ideas about new features for implemented location based information distribution system.
32

Indoor localization using received signal strength

Obeidat, Huthaifa A.N., Abd-Alhameed, Raed, Noras, James M., Zhu, Shaozhen (Sharon), Ghazaany, Tahereh S., Ali, N.T., Elkhazmi, Elmahdi A. January 2013 (has links)
No / A comparison between two indoor localization algorithms using received signal strength is carried out. The first algorithm is the vector algorithm; the second is the matrix algorithm. The comparison considered the effects of the reference points, the access point, and the frequency on the accuracy of the localization process. The experiments were carried out using ray tracing software and MATLAB. This paper justifies the use of adopting the matrix algorithm.
33

Development of Novel Algorithms for Localization in Wireless Sensor Networks

Kumarasiri, Nuwan Rajika January 2014 (has links)
No description available.
34

Ranked set sampling for binary and ordered categorical variables with applications in health survey data

Chen, Haiying 29 September 2004 (has links)
No description available.
35

Nouvelle stratégie d'amélioration de la productivité végétale en condition de stress environnemental via un meilleur contrôle du cycle cellulaire / New strategy for plant improvement productivity under stress conditions via a better control of cell cycle

Mahjoubi, Habib 20 September 2018 (has links)
Le stress salin est l'un des principaux facteurs environnementaux limitant la croissance des plantes et entraînant des pertes de rendement des cultures céréalières. Il est ainsi impératif de développer des variétés plus tolérantes à la salinité afin d’augmenter leurs rendements et assurer la sécurité alimentaire. La voie signalétique reliant la perception du stress salin à la réponse cellulaire, encore peu connue, a été abordée ici par l’étude des protéines RSS1-like conservées chez les plantes. La protéine RSS1 (Rice Salt Sensitive 1) du riz joue un rôle primordial dans la tolérance au stress salin en agissant à l’interface entre la perception des stress et le contrôle du développement et de la division dans les méristèmes. Lors de ce travail, l'homologue de RSS1 nommé TdRL1 (Triticum durum RSS-Like 1) a été isolé à partir de la variété tunisienne de blé dur “Oum Rabiaa“. Nous avons démontré que TdRL1 porte les motifs D et DEN-Box conservés impliqués dans la régulation post-traductionnelle de la protéine. En outre nous avons apporté la preuve que TdRL1 est l’homologue fonctionnel de RSS1 puisqu'il est capable de complémenter le mutant de perte de fonction rss1, hypersensible au stress salin. En outre, l’expression hétérologue de TdRL1 améliore la tolérance au stress salin chez la levure ainsi que chez Arabidopsis et ce par l’augmentation du pouvoir germinatif et la réduction de l’accumulation des espèces oxygénées réactives. Nos études cytologiques ont montré que la protéine TdRL1 est cytoplasmique en interphase et se localise au niveau des microtubules kinétochoriens pendant la mitose. Remarquablement, TdRL1 change de localisation cellulaire sous stress salin et montre une accumulation partielle dans le noyau, soulignant le caractère multifonctionnel de cette protéine dans la réponse au stress salin. L’ensemble des données suggère que sous contrainte saline, TdRL1 joue un rôle dans la régulation du cycle cellulaire en relation avec le réseau microtubulaire. L‘étude de la famille RSS1-like multifonctionnelle permettra ainsi d’aborder de nouvelles voies de recherche pour la création variétale de blé plus résilientes aux stress de l'environnement. / Salt stress is one of the main environmental factors limiting plant growth and yield in cereal crops. It is therefore imperative to develop varieties more tolerant to salt stress in order to increase yield and ensure food security. The signaling pathway linking salt stress perception to cellular response was addressed here by studying RSS1-like proteins in plants. RSS1 (Rice Salt Sensitive 1) protein plays an important role in salt stress tolerance. It acts at the interface of stress perception and developmental control and division in meristems. During this work, the RSS1 counterpart named TdRL1 (Triticum durum RSS-Like 1) was isolated from the durum wheat Tunisian variety "Oum Rabiaa". We have demonstrated that TdRL1 carries the conserved D and DEN-Box motifs involved in the post-translational regulation of the protein. In addition, we show that TdRL1 is the functional homologue of RSS1 since it was able to complement the loss-of-function mutant rss1, hypersensitive to salt stress. In addition, heterologous expression of TdRL1 enhances salt stress tolerance in yeast and in Arabidopsis by increasing germination and reducing the accumulation of reactive oxygen species. Our cytological studies have shown that the TdRL1 protein is cytoplasmic in interphase and is localized at the spindle during mitosis. Remarkably, TdRL1 changes its subcellular localization under salt stress treatment and shows a partial accumulation in the nucleus, highlighting the multifunctional nature of this protein during salt stress response. Our data suggest that under salt stress, TdRL1 plays a role in the regulation of the cell cycle in relation with the microtubule network. Pursuing the study of RSS1-like multifunctional proteins will open up new research areas for the creation of wheat varieties that are more resilient to environmental stresses.
36

Target localization using RSS measurements in wireless sensor networks

Li, Zeyuan January 2018 (has links)
The subject of this thesis is the development of localization algorithms for target localization in wireless sensor networks using received signal strength (RSS) measurements or Quantized RSS (QRSS) measurements. In chapter 3 of the thesis, target localization using RSS measurements is investigated. Many existing works on RSS localization assumes that the shadowing components are uncorrelated. However, here, shadowing is assumed to be spatially correlated. It can be shown that localization accuracy can be improved with the consideration of correlation between pairs of RSS measurements. By linearizing the corresponding Maximum Likelihood (ML) objective function, a weighted least squares (WLS) algorithm is formulated to obtain the target location. An iterative technique based on Newtons method is utilized to give a solution. Numerical simulations show that the proposed algorithms achieves better performance than existing algorithms with reasonable complexity. In chapter 4, target localization with an unknown path loss model parameter is investigated. Most published work estimates location and these parameters jointly using iterative methods with a good initialization of path loss exponent (PLE). To avoid finding an initialization, a global optimization algorithm, particle swarm optimization (PSO) is employed to optimize the ML objective function. By combining PSO with a consensus algorithm, the centralized estimation problem is extended to a distributed version so that can be implemented in distributed WSN. Although suboptimal, the distributed approach is very suitable for implementation in real sensor networks, as it is scalable, robust against changing of network topology and requires only local communication. Numerical simulations show that the accuracy of centralized PSO can attain the Cramer Rao Lower Bound (CRLB). Also, as expected, there is some degradation in performance of the distributed PSO with respect to the centralized PSO. In chapter 5, a distributed gradient algorithm for RSS based target localization using only quantized data is proposed. The ML of the Quantized RSS is derived and PSO is used to provide an initial estimate for the gradient algorithm. A practical quantization threshold designer is presented for RSS data. To derive a distributed algorithm using only the quantized signal, the local estimate at each node is also quantized. The RSS measurements and the local estimate at each sensor node are quantized in different ways. By using a quantization elimination scheme, a quantized distributed gradient method is proposed. In the distributed algorithm, the quantization noise in the local estimate is gradually eliminated with each iteration. Simulations show that the performance of the centralized algorithm can reach the CRLB. The proposed distributed algorithm using a small number of bits can achieve the performance of the distributed gradient algorithm using unquantized data.
37

一個以Web 2.0為基礎之PLM協同測試作業環境

陳誌家 Unknown Date (has links)
本研究以探討協同及PLM為出發點,一方面對PLM目前的發展狀況進行討論,另一方面也對PLM核心協同的概念進行了討論。在了解PLM發展的現況及產品生命週期各環節間協同互動對於PLM的重要性後,本研究以Web 2.0的概念進一步探討其在PLM上的應用。 本研究以V-Model做為情境的探討,並用以分析PLM可加強之處。PLM在支援V-Model測試相關活動情境下,本研究歸納出三項可加強之處。第一,測試相關資料沒有一個共同存取的環境;第二,資訊傳達沒有效率且資訊本身無組織性,,並且使用者在訊息接收及瀏覽上也缺乏較為主動的能力;第三,各部門人員沒有可以共同發表意見的平台。 / This research starts with discussing collaboration and PLM. On one hand it discusses the current development of PLM, and on the other hand it discusses collaboration with is the key concept of PLM. After understanding with the current development of PLM and the importance of collaboration with each product life cycle site in PLM, this research uses the Web 2.0 concept to further discuss its application on PLM. This research uses V-Model to discuss the scenario and analyzes which point PLM can be improved. In the testing relative activities scenario of V-Model with PLM supporting, this research concludes three points which PLM can be improved. First, there is no unified accessing environment for testing relative data. Second, it is ineffective in transforming information and information is not innately organized, and the users have no active abilities to accept message and on browsing. Third, there is no unified platform for each department employees to offer opinions.
38

Personalisierte Filterung von Nachrichten aus semistrukturierten Quellen

Eixner, Thomas 09 July 2009 (has links) (PDF)
Durch die Vielzahl von heterogenen Informationsquellen sehen sich viele Nutzer einer kaum überschaubaren Informationsflut gegenüber. Aus diesem Grund werden durch diese Arbeit die gängigen Nachrichtenformate analysiert und der aktuelle Stand der Technik im Bereich der Nachrichtenaggregatoren dargelegt. Dabei werden diese Analysen immer mit Blick auf die Möglichkeiten einer personalisierten Filterung der Inhalte durchgeführt. Anschließend wird eine im Rahmen dieser Arbeit entstandene Infrastruktur für die Aggregation, personalisierte Filterung und kollaborative Empfehlung von Inhalten aus heterogenen Nachrichtenquellen vorgestellt. Dabei wird detailiert auf die zu Grunde liegenden Konzepte eingegangen und deren praktische Umsetzung beschrieben.
39

Indexation pour la recherche par le contenu textuel de flux RSS / Indexing by content in RSS systems

Hmedeh, Zeinab 10 December 2013 (has links)
Afin de réduire l’intervalle de temps nécessaire entre la publication de l’information sur le Web et sa consultation par les utilisateurs, les sites Web reposent sur le principe de la Syndication Web. Les fournisseurs d’information diffusent les nouvelles informations à travers des flux RSS auxquels les utilisateurs intéressés peuvent s’abonner. L’objectif de la thèse est de proposer un système de notification passant à l’échelle du Web, prenant en considération le grand nombre d’utilisateurs et le débit élevé d’items. Nous proposons un index basé sur les mots-clés des requêtes utilisateurs permettant de retrouver ceux-ci dans les items des flux. Trois structures d’indexation de souscriptions sont présentées. Un modèle analytique pour estimer le temps de traitement et l’espace mémoire de chaque structure est détaillé. Nous menons une étude expérimentale approfondie de l’impact de plusieurs paramètres sur ces structures. Pour les souscriptions jamais notifiées, nous adaptons les index étudiés pour prendre en considération leur satisfaction partielle. Afin de réduire le nombre d’items reçus par l’utilisateur, nous intégrons une deuxième phase de filtrage par nouveauté et diversité considérant l’ensemble d’items déjà reçus par l’utilisateur. / Based on a Publish/Subscribe paradigm, Web Syndication formats such as RSS have emerged as a popular means for timely delivery of frequently updated Web content. According to these formats, information publishers provide brief summaries of the content they deliver on the Web, while information consumers subscribe to a number of RSS feeds and get informed about newly published items. The goal of this thesis is to propose a notification system which scales on the Web. To deal with this issue, we should take into account the large number of users on the Web and the high publication rate of items. We propose a keyword-based index for user subscriptions to match it on the fly with incoming items. We study three indexing techniques for user subscriptions. We present analytical models to estimate memory requirements and matching time. We also conduct a thorough experimental evaluation to exhibit the impact of critical workload parameters on these structures. For subscriptions which are never notified, we adapt the indexes to support a partial matching between subscriptions and items. We integrate a diversity and novelty filtering step in our system in order to decrease the number of notified items for short subscriptions. This filtering is based on the set of items already received by the user.
40

Sustainable utilisation of raw sewage sludge (RSS) as a water replacement in cement-based materials containing unprocessed fly ash

Hamood, Alaa January 2014 (has links)
Prior to the implementation of the European Union Urban Waste Water Treatment Directive (91/271/EEC) in 31 Dec 1998, around a quarter of the sewage sludge produced in the UK was either discharged to surface waters via pipes or disposed from ships at sea. Discontinuing this route together with the quality requirements of the European Waste Water Directive, led to the generation of significant quantities of sewage sludge. It has therefore become required to treat this waste effectively before it can be sent back to the environment. Consequently, this added greater challenges for the environmental agencies, as well as local authorities. The treatment process comprises costly and energy consuming applications including physical, chemical, biological and thermal. In addition to the sewage sludge, the power generation industry produces massive quantities of fly ash from burning coal. In the UK, there is about 5,300,000 tonnes of fly ash that are generated annually, which require to be processed and classified in order to meet the standard requirements before it can be used in the construction applications. The classifying process also involves a series of costly and energy consuming mechanical and physical applications. This research programme has introduced an innovative alternative to the traditional re-use and disposal routes of Raw Sewage Sludge (RSS) and unprocessed fly ash. It has suggested the utilisation of RSS and unprocessed fly ash as raw ingredients for the production of sustainable construction materials. This research programme has therefore examined the performance of cement-based materials containing Raw Sewage Sludge (RSS) as a water replacement and unprocessed fly ash as cement replacement. Mortar and concrete mixes incorporating these materials were tested for their flowability/workability, density, Total Water Absorption (TWA), Ultrasonic Pulse Velocity (UPV), compressive strength, flexural strength, drying shrinkage, sulphate attack and leaching properties. Three series of cement-based materials were studied including mortar mixes with RSS and unprocessed fly ash (Series 1), mortar mixes with RSS and large proportions of unprocessed fly ash (Series 2), and concrete mixes with RSS and unprocessed fly ash (Series 3). The outcomes of the investigation were encouraging in that cement-based materials containing RSS and unprocessed fly ash that were produced demonstrated relatively good engineering, durability and environmental properties in comparison to the control mixes. The inclusion of unprocessed fly ash significantly reduced flowability/workability; however it improved long-term compressive strength for both mixes with RSS and water. The best compressive strength results were recorded when cement was replaced with 10-20% unprocessed fly ash by weight of total binder. The results also showed that sulphate attack resistance improved when fly ash was included. Moreover, safe concentration levels of heavy metals and free ions were detected when leaching test was performed. However, it must be kept in mind that more environmental tests must be performed before any large scale use is undertaken.

Page generated in 0.0356 seconds