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Global and Local Damage Assessment of Structures by Seismic Response Data
No full text這篇論文主要在探討兩種不同的損害檢測方法評估全域性和局部性結構損害。本文中的傷害評估方法大致可分三個步驟：第一是利用量測資料識別狀態空間的結構系統矩陣，並利用結構系統矩陣轉換出動態的物理參數，第二是利用 DLV方法進行全域性損害檢測，第三是使用模態振形曲率的變化量並定義傷害指數評估局部性結構性損害。
狀態空間識別( SRIM )是利用量測資料識別結構系統矩陣，並且利用識別的結構系統矩陣識別二階系統的動態結構矩陣。就傷害檢測而言，結構物( 線性系統 )常被分為破壞前與破壞後兩階段。本論文首先利用四個數值模型為例進行全域性與局部性結構損害檢測，這四個例子分別為：( 1 )三個自由度的剪力構架，( 2 )二維桁架結構，( 3 )兩跨度梁的有限元素模型及( 4 )三層樓房屋構架的有限元素模型。
此外，上述方法也應用於實驗資料。本篇論文選用在國家地震中心的實尺寸三層樓結構進行實驗資料分析，此結構可分為兩種不同的型態：一個是在基準結構一樓加設支撐模擬健康狀態並且移除支撐模擬破壞狀態；另一種是基準結構一樓的柱子進行翼板切削以模擬破壞狀態。由於感測器安裝與數量上的限制，損壞樓層的位移和應變測量資料也被用來識別系統模態振形以進行局部性結構損傷檢測。This study presents two different damage detection algorithms: one is for global damage detection and the other is for local damage detection. For damage detection three steps are proposed: (1) the state-space model identification from input-output measurements to extract the physical parameters, (2) global damage detection using damage locating vector (DLV) method, (3) using the changes of curvature of mode shapes as damage index to localize the position of structural damage for more detail local damage detection.
For state space identification, SRIM method is used to identify the system matrix from input-output measurements and the second-order structural system matrix are also identified from realization model. For damage detection, the pre- and post- damaged structures are identified using the two separate equivalent linear models. In this study four numerical models are selected: (1) a three degree of freedom shear-type Structure, (2) a two-dimensional truss structure, (3) a two span continuous beam represented by finite element model and (4) a three-story finite element model, as examples for global and local damage detection in this study.
Besides, these damage detection methods are also applied to experimental data. Shaking table test of two different benchmark models for SHM research in NCREE is selected for the experimental study. One of the benchmark models is the 3-story steel frame with adding brace at its first floor to simulate the healthy state and removing bracing to simulate the damaged state; the other is the wedge-type cut on the flange of the column at first floor to simulate the damaged state. Because of the limit number of sensors in the implementation, the displacement and strain measurements are also used to extract the mode shape of damaged floor for local damage detection through the usage of damage index.ABSTRACT (IN CHINESE) I
ABSTRACT (IN ENGLISH) II
CONTENTS IV
LIST OF TABLES VI
LIST OF FIGURES VII
Chapter 1: Introduction
1.1 Background and Motivation 1
1.2 Literature Review 1
1.3 Summary 3
Chapter 2: Extracting Physical Parameters using Both Input-Output Measurements
2.1 System Realization Using Information Matrix (SRIM) 7
2.2 Extracting Physical Parameters 14
2.2.1 Theoretical Shear-Type Structural Model 14
2.2.2 Comparing System Realization Model and Theoretical Model 16
2.2.3 Exaction of physical parameters 21
Chapter 3: Damage Detection Techniques
3.1 Global Damage Detection by Using Damage Locating Vector 23
3.1.1 Damage Locating Vector 23
3.1.2 Construction of Flexibility Matrix 26
3.2 Local Damage Detection by Using Damage Indices 27
3.2.1 Damage Index A 28
3.2.2 Damage Index B 29
3.2.3 Estimate nodal response for substructure using strain data 32
Chapter 4: Applications: Numerical Results and Experimental Test
4.1 Numerical Results 34
4.1.1 Example 1: a 3-DOFs Shear-Type Structure 34
4.1.2 Example 2: a Two-Dimensional Truss Structure 36
4.1.3 Example 3: a Two Span Continuous Beam Finite Element Model 39
4.1.4 Example 4: a Three-Story Finite Element Model 40
4.2 Experimental Results 43
4.2.1 Introduction of the Experimental Model and Shaking Table Test 43
4.2.2 Extracting Structural System Parameter 44
4.2.3 Global and Local Damage Detection 45
Chapter 5: Conclusions and Future Works
5.1 Conclusions 49
5.2 Future Works 50
Reference
Energy-Efficient Mapping Technique for Virtual Processors
No full text在現今的系統設計上，虛擬化技術為解決可攜性、可維持性、發展性以及系統使用率的問題上提供了一個極佳的解決方案。本論文中，我們將專注於開發平台虛擬化技術上的省電設計。我們探討了虛擬化核心與真實核心上計算資源的對應技術，以及在考慮系統上執行工作的時間限制下，虛擬化核心與真實核心上能源消耗的關係。透過模組化每個虛擬化核心上所需的執行資源，本論文同時考慮了即時性工作以及非即時性工作上的工作量。以此設計為基礎，本論文提出了一個以微核心為基礎，支援動態電壓調整的原型架構。並評估了此架構的功能以及造成的負擔，實驗結果展示出本設計在省電支援以及系統負擔上，有著良好的結果。Virtualization provides an excellent solution to resolve the portability, maintainability, development, and utilization problems in many system designs. In this paper, we are interested in energy-efficient designs for platform virtualization. In particular, we explore the computing resource mapping between virtual cores and physical cores and their energy consumption relationship when timing constraints in task executions are considered. Real-time and non-real-time task workloads are both considered in the study, where the computing needs of each virtual core is modeled with a computing server. A prototype with DVS support is implemented based on a -kernel architecture. The capability and overheads of the proposed design was evaluated, for which we have encouraging results.Abstract ixontents xiist of Figures xiiiist of Tables xv Introduction 1 System Architecture and Research Motivation 5 Power-Aware Virtualization System 9.1 A Virtual-Core Server Model . . . . . . . . . . . . . . . . . . . . . . . 10.2 Hypervisor Functionalities . . . . . . . . . . . . . . . . . . . . . . . . 14.3 Implementation Remarks . . . . . . . . . . . . . . . . . . . . . . . . . 17 Performance Evaluation 19.1 System Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . 19.2 Experimental Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.2.1 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . 22 Conclusions 27ibliography 2
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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