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Performance-based concept on seismic evaluation of existing bridges 被引量:1
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作者 Yu-Chi Sung Wen-I Liaoi W.Phillip Yen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期127-135,共9页
Conventional seismic evaluation of existing bridges explores the ability of a bridge to survive under significant earthquake excitations. This approach has several major drawbacks, such as only a single structural per... Conventional seismic evaluation of existing bridges explores the ability of a bridge to survive under significant earthquake excitations. This approach has several major drawbacks, such as only a single structural performance of near collapse is considered, and the simplified approach of adopting strength-based concept to indirectly estimate the nonlinear behavior of a structure lacks accuracy. As a result, performance-based concepts that include a wider variety of structural performance states of a given bridge excited by different levels of earthquake intensity is needed by the engineering community. This paper introduces an improved process for the seismic evaluation of existing bridges. The relationship between the overall structural performance and earthquakes with varying levels of peak ground acceleration (PGA) can successfully be linked. A universal perspective on the seismic evaluation of bridges over their entire life-cycle can be easily obtained to investigate multiple performance objectives. The accuracy of the proposed method, based on pushover analysis, is proven in a case study that compares the results from the proposed procedure with additional nonlinear time history analyses. 展开更多
关键词 pushover analysis plastic hinge seismic capacity seismic demand performance-based concepts
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Optimization model for performance-based warranty decision of degraded systems based on improved sparrow search algorithm
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作者 DONG Enzhi CHENG Zhonghua +3 位作者 LIU Zichang ZHU Xi WANG Rongcai BAI Yongsheng 《Journal of Systems Engineering and Electronics》 2025年第5期1259-1280,共22页
Performance-based warranties(PBWs)are widely used in industry and manufacturing.Given that PBW can impose financial burdens on manufacturers,rational maintenance decisions are essential for expanding profit margins.Th... Performance-based warranties(PBWs)are widely used in industry and manufacturing.Given that PBW can impose financial burdens on manufacturers,rational maintenance decisions are essential for expanding profit margins.This paper proposes an optimization model for PBW decisions for systems affected by Gamma degradation processes,incorporating periodic inspection.A system performance degradation model is established.Preventive maintenance probability and corrective renewal probability models are developed to calculate expected warranty costs and system availability.A benefits function,which includes incentives,is constructed to optimize the initial and subsequent inspection intervals and preventive maintenance thresholds,thereby maximizing warranty profit.An improved sparrow search algorithm is developed to optimize the model,with a case study on large steam turbine rotor shafts.The results suggest the optimal PBW strategy involves an initial inspection interval of approximately 20 months,with subsequent intervals of about four months,and a preventive maintenance threshold of approximately 37.39 mm wear.When compared to common cost-minimization-based condition maintenance strategies and PBW strategies that do not differentiate between initial and subsequent inspection intervals,the proposed PBW strategy increases the manufacturer’s profit by 1%and 18%,respectively.Sensitivity analyses provide managerial recommendations for PBW implementation.The PBW strategy proposed in this study significantly increases manufacturers’profits by optimizing inspection intervals and preventive maintenance thresholds,and manufacturers should focus on technological improvement in preventive maintenance and cost control to further enhance earnings. 展开更多
关键词 performance-based warranty gamma process periodic inspection intelligent optimization algorithm
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Metabolic Surgery: Concepts and New Classification
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作者 Paulo Reis Rizzo Esselin de Melo Victor Ramos Mussa Dib +34 位作者 Carlos Augusto Scussel Madalosso Chetan Parmar Omar Ghanem Miguel Ángel Carbajo Ricardo Zorron Amador García Ruiz de Gordejuela Caio Gustavo Gaspar de Aquino Luiz Alfredo Vieira d’Almeida Luciano Antozzi Rui Ribeiro Halit Eren Taskin Jorge Bravo López Christine Stier Patrick Noel José Sergio Verboonen Sotelo Laurent Abram Layani Ramon Vilallonga Puy Elinton Adami Chaim Helmuth Billy Carlos Eduardo Domene Paula Volpe Nilton Tokio Kawahara Augusto Cláudio de Almeida Tinoco Antelmo Sasso Fin Hiroji Okano Júnior Nicholas Tavares Kruel Giorgio Alfredo Pedroso Baretta Diogo Swain Kfouri Anna Carolina Hoff Fernando Reis Esselin Melo Thonya Cruz Braga Clayton Alencar Moreira Luis Poggi Almino Cardoso Ramos Antonio Torres 《Surgical Science》 2025年第2期87-109,共23页
Bariatric and metabolic surgeries have gained extensive popularity and trust due to their documented efficacy and safety in managing not only obesity but also associated comorbidities such as diabetes mellitus, hypert... Bariatric and metabolic surgeries have gained extensive popularity and trust due to their documented efficacy and safety in managing not only obesity but also associated comorbidities such as diabetes mellitus, hypertension, dyslipidemia, sleep apnea, and joint pain. Traditionally, bariatric surgeries have been categorized into hypoabsorptive, restrictive, or hybrid approaches. However, these classifications inadequately reflect the complex anatomical and physiological alterations associated with modern surgical methodologies. This paper explores the evolution of metabolic surgeries, emphasizing the integration of physiological concepts into classic procedures to provide more tailored and effective treatment options for obesity and its comorbidities. Finally, the proposal for a new classification based on current metabolic concepts will facilitate communication among patients, doctors, and healthcare professionals. Additionally, it will enable a more didactic and standardized approach to data collection for conducting studies and publications. 展开更多
关键词 Metabolic Surgery Bariatric Surgery OBESITY Physiological concepts Gastrointestinal Procedures Transit Bipartition Long Common Channel Metabolically Functional Stomach Wide Anastomosis
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Origin and Inheritance of Health Preservation Concepts in Treatise on Cold Damage and Miscellaneous Diseases(Shang Han Za Bing Lun)
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作者 Qingya Li Shuohan Su +5 位作者 Qian Wang Long Feng Haiyan Zhang Liran Xu Dongyang Li Xiaodan Yin 《Chinese Medicine and Natural Products》 2025年第3期135-139,共5页
By analyzing the structure and academic characteristics of early Western Han medical texts such as Prescriptions for Fifty-Two Diseases(Wu Shi Er Bing Fang)and Prescriptions for Health Preservation(Yang Sheng Fang),an... By analyzing the structure and academic characteristics of early Western Han medical texts such as Prescriptions for Fifty-Two Diseases(Wu Shi Er Bing Fang)and Prescriptions for Health Preservation(Yang Sheng Fang),and considering the development of philosophical thinking during the pre-Qin and Han periods,this study summarizes how Zhongjing Zhang’s Treatise on Cold Damage and Miscellaneous Diseases(Shang Han Za Bing Lun)inherited pre-Qin and Han philosophical thought while further integrating Daoist“natural law”cosmology,Confucian“benevolence”social ethics,and the“isomorphic unity of heaven and humanity”medical theory in Yellow Emperor’s Inner Classic(Huang Di Nei Jing).It proposes health preservation concepts encompassing heaven-human,body-spirit,and benevolence perspectives,along with dietary hygiene,representing the medical embodiment of pre-Han“virtue cultivation”and“body nurturing”life philosophies that profoundly influenced subsequent traditional Chinese medicine health preservation theory and practice. 展开更多
关键词 health preservation Treatise on Cold Damage and Miscellaneous Diseases Shang Han Za Bing Lun Zhongjing Zhang heaven-human view body-spirit concept benevolence concept
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Intelligent bionics:Concepts,research and applications
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作者 Jiangeng Huang Zhiyong Chang +3 位作者 Jiangtao Qi Timothy Jakobi Zhihui Zhang Luquan Ren 《Advanced Bionics》 2025年第2期152-155,共4页
Intelligence is the capacity of an entity to adjust to environmental changes and overcome challenges.Intelligence has for all of eternity been a quality exclusive only to living organisms until the emergence of artifi... Intelligence is the capacity of an entity to adjust to environmental changes and overcome challenges.Intelligence has for all of eternity been a quality exclusive only to living organisms until the emergence of artificial intelligence.Thus the term“intelligence”inherently carries a latent“bionic”connotation.In contrast to artificial intelligence,which focuses on replicating and extending human cognitive abilities,bionic intelligence draws inspiration from intelligent behaviors and functions across diverse living organisms to enable bionic systems with low energy consumption,advanced working efficiency and strong task adaptability. 展开更多
关键词 artificial intelligencewhich intelligent bionics concepts RESEARCH living organisms adjust environmental changes artificial intelligencethus applications
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Citation Concept Analysis(CCA)of concepts introduced by Pierre Bourdieu:Measuring their impact across fields and periods
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作者 Lutz Bornmann Charles Crothers Robin Haunschild 《Journal of Data and Information Science》 2025年第1期26-46,共21页
Purpose:Citations can be used in evaluative bibliometrics to measure the impact of papers.However,citation analysis can be extended by a multi-dimensional perspective on citation impact which is intended to receive mo... Purpose:Citations can be used in evaluative bibliometrics to measure the impact of papers.However,citation analysis can be extended by a multi-dimensional perspective on citation impact which is intended to receive more specific information about the kind of received impact.Design/methodology/approach:Bornmann,Wray,and Haunschild(2019)introduced citation concept analysis(CCA)for capturing the importance and usefulness certain concepts have in subsequent research.The method is based on the analysis of citances-the contexts of citations in citing papers.This study applies the method by investigating the impact of various concepts introduced in the oeuvre of the world-leading French sociologist Pierre Bourdieu.Findings:We found that the most cited concepts are‘social capital’(with about 34%of the citances in the citing papers),‘cultural capital’,and‘habitus’(both with about 24%).On the other hand,the concepts‘doxa’and‘reflexivity’score only about 1%each.Research limitations:The formulation of search terms for identifying the concepts in the data and the citation context coverage are the most important limitations of the study.Practical implications:The results of this explorative study reflect the historical development of Bourdieu’s thought and its interface with different fields of study.Originality/value:The study demonstrates the high explanatory power of the CCA method. 展开更多
关键词 BIBLIOMETRICS Citation concept analysis(CCA) Citation content analysis Pierre Bourdieu SOCIOLOGY
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The Basic Human Rights Concepts in Chinese Classics and Their Differences from the West
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作者 ZHAO Jianwen LI Donglin(Translated) 《The Journal of Human Rights》 2025年第1期10-37,共28页
The basic human rights concepts in Chinese classics mainly encompass three categories:the concept of order and freedom influenced by the worldview of the harmony between humanity and nature,the concept of human subjec... The basic human rights concepts in Chinese classics mainly encompass three categories:the concept of order and freedom influenced by the worldview of the harmony between humanity and nature,the concept of human subjectivity and the source of human rights influenced by the people-oriented or benevolence-oriented values,as well as the concept of the relationship between human rights and state power guided by the outlook on life of the great unity of all under heaven(tianxia).Among them,the concept of order and freedom of the harmony between humanity and nature and modeling itself on nature is more beneficial to the stability and development of human society than the Western concept of order and freedom under“rational choice.”The norm prototype of“Do not do to others what you do not want others to do to you”formed the Article 4 of the French Declaration of the Rights of Man and of the Citizen in 1789,and the concepts of“benevolence”and“human superiority”were written into Article 1 of the Universal Declaration of Human Rights and the preamble of the Declaration of the United Nations Conference on the Human Environment,respectively,which have become the common spiritual wealth of all humankind.The ancient Chinese imperial examination system for selecting virtuous and capable people was basically consistent with the provisions on the political rights of citizens to hold public office stipulated in contemporary human rights documents,and was advanced in the world at that time.The contemporary Chinese system of“the state respects and protects human rights”is a system rooted in the Chinese historical and cultural traditions and is with the superiority of socialism. 展开更多
关键词 harmony between humanity and nature PEOPLE-ORIENTED great unity of all under heaven human rights concepts Chinese classics
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Human Rights Concepts and Their Institutional Expressions in Legal Codes:Focusing on the Rights and Protection of Prisoners in the Tang Dynasty
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作者 LIU Xiaolin LI Donglin(Translated) 《The Journal of Human Rights》 2025年第1期38-59,共22页
During the Tang Dynasty,incarcerated prisoners enjoyed various rights during their detention,including access to clothing,food,medical care,hygiene,rest,and burial arrangements.Under specific conditions,prisoners were... During the Tang Dynasty,incarcerated prisoners enjoyed various rights during their detention,including access to clothing,food,medical care,hygiene,rest,and burial arrangements.Under specific conditions,prisoners were even granted leave for family events such as funerals or weddings.The Rules for Prison Officials(Yuguanling)detailed the rights and safeguards for prisoners and set clear guidelines on the use of restraints during detention.Additionally,the Statutes on Deciding Cases(Duanyu Lü)outlined explicit penalties for judicial officials who failed to ensure prisoner rights or committed related violations.Interrogation processes adhered to strict procedural and substantive requirements,including direct questioning by judges,the avoidance of cases involving personal connections or conflicts of interest,evidence-based cross-examinations,careful investigation of circumstances,and consistent rulings across similar cases.The Tang legal code imposed comprehensive,detailed,and stringent limits on the application of coercive interrogations,specifying restrictions on tools,methods,subjects,and extent.Any breaches of these restrictions were met with severe punishments.While the concept of“human rights”did not appear in Tang legal and administrative texts,these laws and regulations embody abundant principles of people-centered governance,benevolence,and human rights concepts.Systematic examination of these ideas,values,and principles—when integrated with the Marxist perspective on human rights—can enrich China’s contemporary human rights practice,contribute to articulating China’s unique narrative on human rights,and play a role in constructing a distinctly Chinese discourse on human rights.Such efforts could provide Chinese wisdom and proposals for the advancement of human rights globally. 展开更多
关键词 Rules for Prison Officials(Yuguanling) Statutes on Deciding Cases(Duanyu Lü) incarcerated prisoner guarantee of rights and interests human rights concepts
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Ecological Concepts in Traditional Vernacular Dwellings of Miao Nationality in Southeast Guizhou Province 被引量:1
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作者 梅军 肖金香 《Journal of Landscape Research》 2010年第1期26-29,共4页
Traditional vernacular dwellings of Miao Nationality in southeast Guizhou Province are reasonable and scientific in many aspects, such as site selection, construction, structure, direction, room layout, harmony betwee... Traditional vernacular dwellings of Miao Nationality in southeast Guizhou Province are reasonable and scientific in many aspects, such as site selection, construction, structure, direction, room layout, harmony between constructions and environment, moderate development of natural resources and so on, which demonstrate the ecological concepts of Miao people respecting the Nature, pursuing the harmonious coexistence between human beings and Nature. This study analyzed the gist of Miao people constructing vernacular dwellings, i.e. natural and harmonious ecological concepts, the principle of planning according to actual conditions, saving cost by utilizing local materials and sustainably developing architectural structure. 展开更多
关键词 MIAO NATIONALITY TRADITIONAL VERNACULAR DWELLINGS Ecological concepts
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外国教材及其辅助教学资源案例浅析——以Molles所著Ecology:Concepts and Applications为例 被引量:3
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作者 段昌群 邹学英 林金安 《中国大学教学》 CSSCI 北大核心 2011年第10期84-86,66,共4页
Manuel C.Molles Jr.所著的Ecology:Concepts and Applications(《生态学:概念与应用》)在教材与网络资源的建设方面进行了有益的尝试,其主教材及辅助教学资源的设计理念值得借鉴。主教材从1999年到2008年出版了4版,主教材内容及版本更... Manuel C.Molles Jr.所著的Ecology:Concepts and Applications(《生态学:概念与应用》)在教材与网络资源的建设方面进行了有益的尝试,其主教材及辅助教学资源的设计理念值得借鉴。主教材从1999年到2008年出版了4版,主教材内容及版本更新快,力求及时反映学科前沿水平的新技术、新知识;正文内容和版式编排设计以读者为本,注重为学生服务;网上辅助教学资源围绕主教材的系列产品进行整体设计,体现利教利学的建设理念,既为教师教学提供帮助和指导,也重视给予学生自我发挥的空间,网站展示条理清晰,内容布局规范,内容介绍注重以读者为中心,满足不同客户的需求。 展开更多
关键词 Ecology:concepts and Applications(《生态学:概念与应用》) 生态学 教材 辅助教学资源
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Status of and Strategies for the Planning and Design, Maintenance and Management of Chinese Urban Green Land——Application of Ecological Concepts in This Field
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作者 魏胜林 徐梦萤 张辉 《Journal of Landscape Research》 2010年第8期17-20,共4页
The sustainability of the planning and design goals of urban green land and that of its maintenance and management are mutually related and act as an organic whole. For a long time, the independence of the two is more... The sustainability of the planning and design goals of urban green land and that of its maintenance and management are mutually related and act as an organic whole. For a long time, the independence of the two is more prominent than their organic connection. This research has made preliminary considerations from three aspects. First, it concerns infusing the concept of ecology, contemplating and demonstrating space, as well as reducing the incidence of plant diseases and insect pests of urban green land. Second, the arrangement of flowers and trees for the planning and design of urban green land should comply with the biological attributes of flowers and trees to realize the organic unification of biological and scenic attributes of flowers and trees. Third, the planning and design of urban green land should attach importance to the organic unification of biological and scenic attributes of lawn grass seeds and reduce the difficulty of maintaining lawn. This research attempts to reduce the pressure of maintaining urban green land from the beginning, i.e. the planning and design of urban green land. It also tries to reduce the cost of maintenance and management to the realize planning and design goals of urban green land and the sustainability concerning its maintenance and management and arrive at the mutual unification of the planning and design as well as maintenance and management of urban green land. 展开更多
关键词 URBAN green LAND Planning and design Maintenance concept of ECOLOGY SUSTAINABILITY
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Struggling in a Chaste Labyrinth:Tess,a Victim in Traditional Moral Concepts
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作者 商学君 许林林 《海外英语》 2013年第3X期1-3,共3页
The present article makes comments on the film,Tess and draws the conclusion that the film carved a resourceful heroine and showed the audience a real,alive social world and also let us review our social moral standar... The present article makes comments on the film,Tess and draws the conclusion that the film carved a resourceful heroine and showed the audience a real,alive social world and also let us review our social moral standards through the character,which is a victim of traditional moral concepts. 展开更多
关键词 TESS TRADITIONAL MORAL concept VICTIM
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Enigma of Exam-oriented Education in China:A comparison on Sino-U.S.Educational Concepts in Higher Education
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作者 何爱玲 杨坚 《海外英语》 2013年第1X期99-101,共3页
College English teaching in China has long been criticized for its orientation to examination that consequently brings about negative learning attitude and ineffective learning achievement.Chinese educationists have b... College English teaching in China has long been criticized for its orientation to examination that consequently brings about negative learning attitude and ineffective learning achievement.Chinese educationists have brought forward several ap proaches to solve this problem but little has been changed due to the cultural influences.This paper analyzes the roots of examoriented education system in China in perspective of culture by comparing the Sino-U.S.cultural elements in depth in tradition al culture,learning and teaching motivation,teacher-student relationship and learners'engagement in class.This paper finally poses two suggestions on how to change the current situation gradually:(1) Focus on the washback of evaluation system on edu cational concepts.(2) Transform the product-evaluation to process-evaluation gradually by standardizing the current evaluation approaches,especially the standards of process-evaluation. 展开更多
关键词 Sino-U.S.teaching concepts motivation teacher-stud
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Low-carbon Concepts in the Planning of Residential Communities 被引量:1
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作者 胡晓康 李国庆 《Journal of Landscape Research》 2011年第1期44-47,51,共5页
It has become a common pursuit of designers to construct comfortable,energy-conserving,high-efficiency and natural living environment since the early 21st century.In the coming low-carbon age,the evolution of low-carb... It has become a common pursuit of designers to construct comfortable,energy-conserving,high-efficiency and natural living environment since the early 21st century.In the coming low-carbon age,the evolution of low-carbon concepts will surely bring positive influence on the present planning concepts of residential community,and meanwhile,propose higher requirements on the natural and ecological properties of residential community,such as its infrastructure construction,traffic organization,environment greening and so on.Through analyzing relevant concepts of low carbon,the authors studied the development of low-carbon concepts in "human-centered" designs,and its applications in architecture,traffic and green spaces.This study proposed that the improvement of low-carbon society could be started from the design of low-carbon residential communities,so as to satisfy the increasing ecological needs of people on living environment,and play a promotional role in facilitating the sustainable development of society. 展开更多
关键词 Low-carbon concepts Development of HUMAN-CENTERED concepts Low-carbon ARCHITECTURE Low-carbon TRAFFIC Green space PLANNING
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Concepts and Issues in Healthcare Computing
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作者 韩颖 陈永霞 《科技信息》 2010年第33期214-215,共2页
This project is going to use online health information to arouse public understanding heart disease and their risk of having heart disease.Consequently,people can prevent the risk of suffering in this chronic disease.... This project is going to use online health information to arouse public understanding heart disease and their risk of having heart disease.Consequently,people can prevent the risk of suffering in this chronic disease.This project collected heart disease information from Internet and library.The information are organized and become the content of the website to provide health information online.The information of definition of heart disease,types of heart disease,symptom of heart diseases,recommendations of heart disease and causes of heart disease are gathered and summarized into the main content of the website.There are three risk of having heart disease interactive calculators been developed and providing recommendation for the user.The website suggests some recommended heart disease websites for user to find more heart disease information. 展开更多
关键词 互联网 WWW 网站 信息
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Performance-based methodology for assessing seismic vulnerability and capacity of buildings 被引量:14
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作者 Lin Shibin1, Xie Lili1, 2,Gong Maosheng1,2 and Li Ming1,3 1.Institute of Engineering Mechanics,China Earthquake Administration, Harbin 150080, China 2.School of Civil Engineering,Harbin Institute of Technology,Harbin 150090, China 3.School of Civil Engineering,Shenyang Jianzhu University,Shenyang 11016, China 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第2期157-165,共9页
This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved ca... This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed. 展开更多
关键词 performance-based VULNERABILITY building damage seismic capacity software HAZUS
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Chemical Concepts from Density Functional Theory 被引量:3
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作者 LIU Shubin ZHANG Xiaojuan 《物理化学学报》 SCIE CAS CSCD 北大核心 2018年第6期563-566,共4页
Chemical concepts such as structure,bonding,reactivity,etc.have been widely used in the literature and text books to appreciate molecular properties and chemical transformations.Even though modern theoretical and comp... Chemical concepts such as structure,bonding,reactivity,etc.have been widely used in the literature and text books to appreciate molecular properties and chemical transformations.Even though modern theoretical and computational chemistry is well established from the perspective of accuracy and complexity,how to quantify these concepts is a still unresolved task.Conceptual density functional theory and its related recent developments provide unique opportunities to tackle this problem.In this Special Issue,27 contributions from top investigators over the world are collected to highlight the state-of-art research on this topic,which not only showcases the status of where we are now but also unveils a number to possible future directions to be pursued. 展开更多
关键词 CHEMICAL concepts DENSITY FUNCTIONAL THEORY
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Performance-based seismic design of nonstructural building components:The next frontier of earthquake engineering 被引量:20
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作者 Andre Filiatrault Timothy Sullivan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第S1期17-46,共30页
With the development and implementation of performance-based earthquake engineering,harmonization of performance levels between structural and nonstructural components becomes vital. Even if the structural components ... With the development and implementation of performance-based earthquake engineering,harmonization of performance levels between structural and nonstructural components becomes vital. Even if the structural components of a building achieve a continuous or immediate occupancy performance level after a seismic event,failure of architectural,mechanical or electrical components can lower the performance level of the entire building system. This reduction in performance caused by the vulnerability of nonstructural components has been observed during recent earthquakes worldwide. Moreover,nonstructural damage has limited the functionality of critical facilities,such as hospitals,following major seismic events. The investment in nonstructural components and building contents is far greater than that of structural components and framing. Therefore,it is not surprising that in many past earthquakes,losses from damage to nonstructural components have exceeded losses from structural damage. Furthermore,the failure of nonstructural components can become a safety hazard or can hamper the safe movement of occupants evacuating buildings,or of rescue workers entering buildings. In comparison to structural components and systems,there is relatively limited information on the seismic design of nonstructural components. Basic research work in this area has been sparse,and the available codes and guidelines are usually,for the most part,based on past experiences,engineering judgment and intuition,rather than on objective experimental and analytical results. Often,design engineers are forced to start almost from square one after each earthquake event: to observe what went wrong and to try to prevent repetitions. This is a consequence of the empirical nature of current seismic regulations and guidelines for nonstructural components. This review paper summarizes current knowledge on the seismic design and analysis of nonstructural building components,identifying major knowledge gaps that will need to be filled by future research. Furthermore,considering recent trends in earthquake engineering,the paper explores how performance-based seismic design might be conceived for nonstructural components,drawing on recent developments made in the field of seismic design and hinting at the specific considerations required for nonstructural components. 展开更多
关键词 nonstructural building components performance-based earthquake engineering seismic design and analysis
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Operational concepts of HVDC in the context of security assessment in the German transmission grid 被引量:5
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作者 Annika Klettke Marius Sieberichs Albert Moser 《Global Energy Interconnection》 2019年第2期130-132,共3页
Because of the realization of HVDC connections parallel to the synchronous grid in Germany, operational concepts become more important in the context of system security aspects. In this article commonly known concepts... Because of the realization of HVDC connections parallel to the synchronous grid in Germany, operational concepts become more important in the context of system security aspects. In this article commonly known concepts are analyzed regarding their suitability for the German transmission system. Therefore, an approach for the analysis was developed and exemplary results are given using this approach. Under consideration of the overall system, the concepts of reducing losses in combination with minimizing(n-1)-warnings or-indications^1 as well as the sole minimization of(n-1)-warnings and-indications are the most reasonable approaches. However, under grid security aspects best results can be achieved by reducing operational limits and therefore, by the minimization of(n-1)-warnings. 展开更多
关键词 System SECURITY Transmission GRID OPERATIONAL concept HVDC
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Core concepts of landscape ecology 被引量:3
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作者 Xiao Du ning, Li Xiu zhen Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110015, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第2期4-8,共5页
People from different backgrounds may have various opinions and methods dealing with landscape ecology. As a basic ecology theory for decision making in land use planning and resource management, it should provide s... People from different backgrounds may have various opinions and methods dealing with landscape ecology. As a basic ecology theory for decision making in land use planning and resource management, it should provide sound scientific principles, which means some core concepts for landscape ecology need to be established. This paper attempts to introduce some core concepts for landscape ecology, with brief analysis, including: the integrity of landscape system and the heterogeneity of landscape elements; scale in landscape ecology; mosaics of landscape structure; spatial aggregation and spread of ecological flow; physical cultural nature of landscape; the irreversible and human dominated landscape evolution; the multi value of landscape. 展开更多
关键词 landscape ecology core concept MOSAIC ecological flow multi value.
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