1,720,981 research outputs found
HCDD: Hierarchical Cluster- based Data Dissemination in Wireless Sensor Networks with Mobile Sink
No full textHCDD: Hierarchical Cluster-based Data Dissemination in Wireless Sensor Networks with Mobile Sink
No full text在無線感測網路中，要有效率地對會移動的資料接收點傳送資料，是一個很難的問題。這是因為受限於感測器的有限資源，如能源、存取空間、還有有限的計算能力。雖然把移動資料接收點的位置資訊廣播到整個網路上是一個直覺的解決方法，但是它會很容易的把感測器的電池能源用完。所以，我們提出一個以階層式叢集導向的方法，叫HCDD，它在很少的負擔下去傳送資料。此外，不像其它的文獻所提，我們的方法能在沒有點的位置資訊就能運作。換句話說，它不需要任何像GPS這類昂貴且花能源的裝置。最後我們會在模擬結果中，展現出HCDD比TTDD等類似的方法，有比較好的資料傳送、較長的網路生命、和比較低的額外負擔Data Dissemination to mobile sinks within wireless sensor networks is a difficult problem due to limited resources of sensors, such as energy, storage capacity, and computing capability. Although flooding the location information of mobile sinks seems to be a naive solution to sink mobility, it drains the sensors of their
battery power rapidly. Thus, we propose a hierarchical
cluster-based approach, named HCDD, to disseminate data to the mobile sink with light overhead. In addition, unlike other works, our approach operates without location information of nodes, that is, it does not need any expensive and power-consuming GPS devices. Finally, we will show that HCDD has better data delivery, longer network lifetime, and lower overhead compared with
TTDD-like methods in simulation results.- Title
- 致謝
- Abstract in English
- 中文摘要
1 Introduction 1
1.1 Background 1
1.2 An Illustration of Application with Mobile Sink 2
1.3 Motivation 2
1.4 Diferences of Routing Between Sensor Networks and Ad Hoc Networks 3
1.5 Problem Refinement 4
1.6 Our Contribution 4
1.7 Paper Organization 5
2 Related Works 6
2.1 Flooding Approach 6
2.2 Grid-Like Approach 7
2.3 Registration Approach 9
3 A GPS-Free Solution: Hierarchical Cluster-based Data Dissemination(HCDD) 11
3.1 Our Intuitive Idea 11
3.2 System Description 12
3.3 Cluster Formation 14
3.4 Sink Location Registration 15
3.5 Data Delivery 16
4 Performance Evaluation and Discussion 18
4.1 Simulation Environment and Setup 18
4.2 Infuence of Diferent Parameters Used in Cluster-based and Grid-based Methods 21
4.2.1 Overhead 21
4.2.2 Network Lifetime 21
4.2.3 Delivery Rate and Successfully Received Packets 23
4.2.4 Average Packet Route Length 28
4.2.5 Data Delivery Latency 28
4.3 Comparison Between Cluster-based Approach and Grid-based Dissemination Approach 32
4.3.1 Overhead 32
4.3.2 Network Lifetime 33
4.3.3 Delivery Rate and Successfully Received Packets 34
4.3.4 Average Packet Route Length and Data Delivery Latency 36
4.4 Comparisons From Another Viewpoint 37
4.4.1 Overhead and Network Lifetime 37
4.4.2 Successfully Received Packets 39
4.4.3 Relation Between Route Length and Delivery Latency 39
5 Conclusions and Future Works 42
A Max-Min D-Cluster Formation Algorithm 43
A.1 Approach Description 43
A.1.1 Data Structures Used in the Algorithm 43
A.1.2 Term Definition 44
A.1.3 Basic Idea 4
Enhancing the performance of multi-source streaming system using the MCMCF-based algorithm
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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