1,721,004 research outputs found
An Energy-Efficient Data-Centric Routing Algorithm in Wireless Sensor Networks
No full text近年來無線感測網路在諸多領域上具有高度應用價值，已被視為下一階段無線通訊技訊的殺手級應用。然而受限於硬體以及應用環境，使感測器對於能源消秏具有高度的限制性，因此在感測網路中降低感測器於運作過程所消秏的能源已成為一個重要的研究議題。結合資料集縮 (data aggregation) 能力於感測器中藉此減少資料傳輸量能有效降低感測器的能源消秏，而具備資料集縮能力之感測網路需有以資料為中心 (data-centric) 之路由演算法來充份利用此能力以達到節省能源消秏的目的。
本篇論文研究在感測器具有資料集縮能力之無線感測網路中，建立兼具最小能源消秏量及服務品質之資料集縮樹 (data aggregation tree) 的問題，在考量感測器之路由指定、傳輸半徑 (communication radius) 及資料重傳 (data retransmission) 限制下，透過集縮樹的方式盡可能減少資料的傳輸總量，使感測網路回報資料時所需消秏之總能量最小化，藉此提高感測網路的系統生存時間。此外，為了使問題能更符合應用環境，在考量資料集縮所帶來的集縮延遲時間限制下，我們將最大端對端延遲 (maximum end-to-end delay) 的概念考慮進來，並加以定義為感測器所消秏之集縮等待能源消秏，藉以更精確的描述感測網路的總能源消秏。
我們將整個問題數學模式化為一個嚴謹的混合式整數線性最佳化數學模型，目標函式為最小化資料傳輸所需之總能源消秏，此數學問題在本質上是一個整數非線性規劃問題，問題本身具有高度的複雜性和困難度。本論文採用以拉格蘭日鬆弛法為基礎的方法來處理此一複雜問題，並根據所得到的結果改良演算法以得到較佳的資料集縮樹。實驗結果顯示，我們不但能有效率地求得此問題解，且在問題解的效能上亦比其它既有的演算法更為優越。Recently wireless sensor networks (WSNs) have attracted a great deal of attention due to their potential for numerous military, environmental detection, and civil applications. Sensor nodes in WSNs are highly energy-constrained, because of the limitations of hardware and the infeasibility of recharging sensor nodes under a severe environment. When a sensor is in operation, therefore, reducing energy consumption during the forwarding and sensing of data is a crucial issue in WSNs. Incorporating sensor nodes with data aggregation capabilities to transmit less data in WSNs could reduce total energy consumption. However, this calls for an efficient and effective data-centric routing algorithm to facilitate this potential advantage.
In this thesis, our work emphasizes on the construction of an energy-efficient data aggregation tree that possesses good QoS and minimizes the total energy consumption of sensor nodes simultaneously. In the first part of this thesis, we model the data-centric routing problem based on a rigorous mixed integer linear mathematical formulation, where the objective function is to minimize the total transmission cost, subject to multicast tree and data aggregation constraints. With the advances in sensor network technology, sensor nodes with configurable transmission radius capability would further reduce energy consumption. Thus, the second part of this paper considers the transmission radius assignment of each sensor node and the data-centric routing assignment jointly. The objective function is to minimize the total power consumption together with consideration of construction of a data aggregation tree and sensor node transmission radius assignment. Finally, the effects of data retransmission and maximum end-to-end delay due to data aggregation delay are also considered in order to reflect the tradeoff between the advantages and the costs of data aggregation. We take the properties of QoS in wireless sensor networks as a new energy consumption metric that can not only maintain the traditional transmission delay, but also simultaneously reduce the energy consumption of sensor nodes operating in idle mode. How to construct a data aggregation tree that is energy-efficient and has QoS properties is a complicated problem that needs to be investigated. We conceive a rigorous mathematical formulation, where the objective function is to minimize the total energy consumption of data transmission subject to tree, data retransmission, and maximum end-to-end delay constraints.
The solution approach is based on Lagrangean relaxation in conjunction with novel optimization-based heuristics. With the exceptional properties of Lagrangean relaxation we are able to efficiently solve this complicated optimization problem, and derive an effective algorithm for routing assignments and construct a data aggregation tree simultaneously. Through our computational experiments, we show that the proposed algorithms calculate better solutions than other existing heuristics. When considering QoS routing in WSNs, the proposed algorithms can not only construct a better data aggregation tree in terms of energy consumption, but also maintain good maximum end-to-end delay.謝 誌 I
論文摘要 III
THESIS ABSTRACT V
Table of Contents IX
List of Tables XII
List of Figures XIV
Chapter 1 Introduction 1
1.1 Background 1
1.2 Motivation 7
1.3 Literature Survey 9
1.3.1 Data Aggregation Tree without QoS 9
1.3.2 Data Aggregation Tree with QoS 12
1.4 Proposed Approach 15
1.5 Thesis Organization 16
Chapter 2 Problem Formulation of DCR and EDCR 17
2.1 Problem Description 17
2.2 Problem Formulation 18
2.2.1 DCR Problem 18
2.2.2 EDCR Problem 24
Chapter 3 Data Aggregation Tree with QoS Routing 27
3.1 Problem Description 27
3.2 Problem Formulation 31
3.3 Extension to the Model without Aggregation 40
Chapter 4 Solution Approach 41
4.1 Lagrangean Relaxation Method 41
4.2 DCR Problem 44
4.2.1 Solution Approach 44
4.2.2 Lagrangean Relaxation 44
4.2.3 The Dual Problem and the Subgradient Method 47
4.3 EDCR Problem 48
4.3.1 Solution Approach 48
4.3.2 Lagrangean Relaxation 48
4.3.3 The Dual Problem and the Subgradient Method 51
4.4 Data Aggregation Tree with QoS Routing 53
4.4.1 Solution Approach 53
4.4.2 Lagrangean Relaxation 53
4.4.3 The Dual Problem and the Subgradient Method 61
Chapter 5 Getting Primal Feasible Solutions 63
5.1 Getting Primal Feasible Solutions of DCR 63
5.2 Getting Primal Feasible Solutions of EDCR 67
5.3 Getting Primal Feasible Solutions for Data Aggregation Tree with QoS Routing 70
Chapter 6 Computational Experiments 75
6.1 Computational Experiments of DCR 75
6.1.1 Experiment Environments 75
6.1.2 Experiment Results 76
6.2 Computational Experiments of EDCR 80
6.2.1 Experiment Environments 80
6.2.2 Experiment Results 81
6.3 Computational Experiments of Data Aggregation Tree with QoS Routing 84
6.3.1 Experiment Environments 84
6.3.2 Experiment Results 86
Chapter 7 Conclusion and Future Works 94
7.1 Summary 94
7.2 Future Works 96
Reference 97
Appendix 9
Evaluation of M2-based avian influenza virus vaccine using an adenovirus vector
No full text一般商業化之家禽流行性感冒病毒之疫苗對於不同HA亞型之家禽流行性感冒病毒感染無交叉保護力。因此，本實驗以發展具交叉保護之疫苗為目的，利用複製缺陷腺病毒 (replication deficient adenovirus) 作為載體，建構帶有不同亞型間保守度高之M2基因片段的重組腺病毒 (Ad/M2)，再將Ad/M2免疫雞隻。Ad/M2感染之293A細胞及轉導之Vero細胞以間接螢光免疫分析皆有陽性訊號產生。在Ad/M2免疫雞隻的實驗結果顯示，補強後2週CD4+及CD8+ T cell相較於初次免疫有顯著增加；抗M2特異性抗體則於初次免疫後2週有顯著增加，但補強後的抗體上升效果則不明顯。於攻毒後第4天及第7天採集的喉頭拭子之real time RT-PCR結果顯示免疫組與對照組之間的AIV含量沒有差異，而攻毒後免疫組與對照組死亡率分別為40%及33.3%，給予Ad/M2之組別並無法對抗AIV感染。Current vaccines to avian influenza virus can’t induce broad cross-protection against different subtypes. Therefore, the purpose of this research was to develop a vaccine which can confer cross-protection by using replication-deficient adenovirus as a vector to construct a recombinant adenovirus carrying highly conserved M2 gene (Ad/M2). The immunofluorescence assay revealed positive signal in 293A and Vero cells transduced with Ad/M2. The Ad/M2 was intranasally and intramuscularly immunized in chickens twice at a 4-week interval. Anti-M2 specific antibody was significantly higher after two weeks post primary vaccination. Challenging with AIV after two weeks post boost vaccination, the consequence of real time RT-PCR revealed AIV content was no difference between Ad/M2 group and control group in oropharyngeal swab on day 4 and day 7 post challenge. The mortality of Ad/M2 group and control group was 40% and 33.3% respectively. The conclusion is giving chickens Ad/M2 couldn’t confer protection against AIV infection
Political and Economic Analysis of the Cross-Strait Negotiation Mechanism, 1991-2015
No full text1980年代以來，東歐國家在因應國際環境變遷與內部經濟改革需求而來的政經變動，更進一步於1990年中期後徹底打破二次大戰以來所構築的冷戰體系，兩岸自1980年代以來，中國大陸和臺灣的政治結構亦產生巨大的轉變，1987年政府宣佈開放臺灣民眾赴大陸探親，開啟兩岸接觸往來重要的里程碑。1991年「民間中介團體」海峽交流基金會、海峽兩岸關係協會正式設立，24餘年來，兩岸關係發展起伏迭宕，亞太地區政經情勢發展、國內政黨政治民主演進遞嬗，在在影響牽動兩岸協商機制的協商型態與政策作為。 本研究旨在就1991年至2015年兩岸協商機制進行相關研析，並以臺灣觀點與國際協商機制為主要比較研析範疇，核心主軸則以「一個中國」的實質概念與實務運作演進貫穿整體分析脈絡。 本研究發現，「一個中國原則」的兩岸協商實質概念與實務運作，在不同政黨執政時期，清楚呈現在協商機制的實務運作，兩岸協商機制實務運作，應從整體治理的概念出發，提出具體實務政策參考建言。Since the 1980s, Eastern European countries have gone through political and economic changes in response to dynamic international circumstances and domestic economic reforms. In the mid 1990s, moreover, they disintegrated the cold war blocs which had been formed after the Second World War. As for Taiwan and China, the political structures have also undergone major changes since the 1980s. In 1987, the Taiwan government lifted the ban on travel to China, marking a momentous milestone in cross-strait communication. In 1991, quasi-private intermediate organizations, the Straits Exchange Foundation of Taiwan and the Association for Relations across the Taiwan Straits of China, were established. Over the past two decades, cross-strait relations, political and economic climate in the Asia-Pacific region, and party politics and democratic progress have all played a significant role in making an impact on negotiation patterns and policy-making of the cross-strait negotiation mechanism. This paper aims to study and analyze the cross-strait negotiation mechanism during 1991 and 2015 from Taiwan’s perspectives and refers to international negotiation mechanisms for comparison. The concept and practicality of the One China principle serve as the underlying thread that weaves through the main context of the paper. This study shows that the concept and practicality of the One China principle have been vividly present at the negotiation mechanism regardless of the ruling party. The practicality of the cross-strait negotiation mechanism should be able to provide feasible suggestions for policy-making based on the notion of overall governance
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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