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Performance Evaluation of Damaged T-Beam Bridges with External Prestressing Reinforcement Based on Natural Frequencies
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作者 Menghui Hao Shanshan Zhou +4 位作者 Yongchao Han Zhanwei Zhu Qiang Yang Panxu Sun Jiajun Fan 《Structural Durability & Health Monitoring》 2025年第2期399-415,共17页
As an evaluation index,the natural frequency has the advantages of easy acquisition and quantitative evaluation.In this paper,the natural frequency is used to evaluate the performance of external cable reinforced brid... As an evaluation index,the natural frequency has the advantages of easy acquisition and quantitative evaluation.In this paper,the natural frequency is used to evaluate the performance of external cable reinforced bridges.Numerical examples show that compared with the natural frequencies of first-order modes,the natural frequencies of higher-order modes are more sensitive and can reflect the damage situation and external cable reinforcement effect of T-beam bridges.For damaged bridges,as the damage to the T-beam increases,the natural frequency value of the bridge gradually decreases.When the degree of local damage to the beam reaches 60%,the amplitude of natural frequency change exceeds 10%for the first time.The natural frequencies of the firstorder vibration mode and higher-order vibration mode can be selected as indexes for different degrees of the damaged T-beam bridges.For damaged bridges reinforced with external cables,the traditional natural frequency of the first-order vibration mode cannot be used as the index,which is insensitive to changes in prestress of the external cable.Some natural frequencies of higher-order vibration modes can be selected as indexes,which can reflect the reinforcement effect of externally prestressed damaged T-beam bridges,and its numerical value increases with the increase of external prestressed cable force. 展开更多
关键词 Performance evaluation natural frequency T-beam bridge DAMAGE external cable reinforcement
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A Systematic Review and Performance Evaluation of Open-Source Tools for Smart Contract Vulnerability Detection
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作者 Yaqiong He Jinlin Fan Huaiguang Wu 《Computers, Materials & Continua》 SCIE EI 2024年第7期995-1032,共38页
With the rise of blockchain technology,the security issues of smart contracts have become increasingly critical.Despite the availability of numerous smart contract vulnerability detection tools,many face challenges su... With the rise of blockchain technology,the security issues of smart contracts have become increasingly critical.Despite the availability of numerous smart contract vulnerability detection tools,many face challenges such as slow updates,usability issues,and limited installation methods.These challenges hinder the adoption and practicality of these tools.This paper examines smart contract vulnerability detection tools from 2016 to 2023,sourced from the Web of Science(WOS)and Google Scholar.By systematically collecting,screening,and synthesizing relevant research,38 open-source tools that provide installation methods were selected for further investigation.From a developer’s perspective,this paper offers a comprehensive survey of these 38 open-source tools,discussing their operating principles,installation methods,environmental dependencies,update frequencies,and installation challenges.Based on this,we propose an Ethereum smart contract vulnerability detection framework.This framework enables developers to easily utilize various detection tools and accurately analyze contract security issues.To validate the framework’s stability,over 1700 h of testing were conducted.Additionally,a comprehensive performance test was performed on the mainstream detection tools integrated within the framework,assessing their hardware requirements and vulnerability detection coverage.Experimental results indicate that the Slither tool demonstrates satisfactory performance in terms of system resource consumption and vulnerability detection coverage.This study represents the first performance evaluation of testing tools in this domain,providing significant reference value. 展开更多
关键词 Blockchain security ethereum smart contracts detection tools evaluation
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Research on the Internal Talent Training Path and Performance Evaluation Mechanism of New R&D Institutions in Zhejiang Province
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作者 Xiangjiang Li 《Proceedings of Business and Economic Studies》 2024年第2期100-105,共6页
New research and development(R&D)institutions are an important part of the national innovation system,playing an important role in promoting the transformation of scientific and technological achievements.In recen... New research and development(R&D)institutions are an important part of the national innovation system,playing an important role in promoting the transformation of scientific and technological achievements.In recent years,new R&D institutions have gradually become the driving force of innovation-driven development in China.Taking new R&D institutions in Zhejiang Province as the research object,this paper studies the internal talent training path and performance evaluation mechanism of new R&D institutions in Zhejiang Province by using the literature research method,comparison method,case verification method,and other methods.The investigation results show that there are problems such as lack of material and spiritual support and neglect of the absorption of local talents in the internal talent training,and there are problems such as unclear standards,insufficient data,and opaque processes in the performance evaluation mechanism,which greatly affect the establishment and improvement of the performance evaluation mechanism.Given the above problems,this paper puts forward a forward-looking,oriented,flexible,and compatible talent training path and performance evaluation mechanism,hoping to optimize the effective internal talent training path of new R&D institutions,improve the evaluation performance,and promote healthy development of new R&D institutions in Zhejiang Province. 展开更多
关键词 INNOVATION New R&D institutions Zhejiang Province Talent cultivation Performance evaluation mechanism
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Construction of Tourist Satisfaction Degree Evaluation Model in Western Tourist Area by Performance Prism and Fuzzy Comprehensive Evaluation Method——with Lijiang in Yunnan Province as the Study Case
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作者 蒋蓉华 焦俊刚 刘曲华 《Journal of Landscape Research》 2010年第4期64-68,共5页
Starting from the utilization and protection of local knowledge, with the performance prism as the framework, the evaluation index system of tourist satisfaction degree was established. The weight was determined by us... Starting from the utilization and protection of local knowledge, with the performance prism as the framework, the evaluation index system of tourist satisfaction degree was established. The weight was determined by using AHP method. Finally, the investigating result was judged with fuzzy comprehensive evaluation method, the evaluation model of tourist satisfaction degree in western tourist area was built, and the case study was carried out. With Lijiang in Yunnan Province as example, according to AHP method, five dimensions weight of the performance prism, various KPI weight and consistency were obtained, fuzzy evaluation on tourist satisfaction degree was conducted. The results showed that the overall was satisfactory, but there were still some problems. Aiming at the utilization and protection of local knowledge, some corresponding countermeasures were put forward which will benefit for further development of tourism in Lijiang of Yunnan Province. 展开更多
关键词 Toursit SATISFACTION degree Performance PRISM Fuzzy comprehensive evaluation evaluation model
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Simplified stiffness-based approach for seismic performance evaluation of moment-resisting frame
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作者 于琦 孟少平 +1 位作者 吴京 孙巍巍 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期241-246,共6页
Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis (e... Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis (e. g. the pushover analysis), and the structural damage is considered via plastic hinges. Simultaneously, a practical approach is developed to obtain the relationships between the proposed index and earthquake intensities based on the capacity spectrum method. The proposed index is then illustrated through two low-rise reinforced concrete frames, and it is also compared with some other indices. The results indicate that the proposed index is on the safe side and not sensitive to the lateral load pattern. The storey index is helpful to reflect the storey damage and to uncover the position of the weak storey. Finally, the relationship between performance levels and damage index values is also proposed through statistical analysis for the performance-based seismic evaluation. 展开更多
关键词 damage index seismic evaluation capacity spectrum method FRAME lateral load pattern pushover analysis performance level stiffness degradation
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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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Future of non-invasive graft evaluation:A systematic review of proteomics in kidney transplantation
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作者 Eleni Avramidou Konstantina Psatha +2 位作者 Kallisti St John Georgios Tsoulfas Michalis Aivaliotis 《World Journal of Transplantation》 2025年第1期135-149,共15页
BACKGROUND Despite the developments in the field of kidney transplantation,the already existing diagnostic techniques for patient monitoring are considered insufficient.Protein biomarkers that can be derived from mode... BACKGROUND Despite the developments in the field of kidney transplantation,the already existing diagnostic techniques for patient monitoring are considered insufficient.Protein biomarkers that can be derived from modern approaches of proteomic analysis of liquid biopsies(serum,urine)represent a promising innovation in the monitoring of kidney transplant recipients.AIM To investigate the diagnostic utility of protein biomarkers derived from proteomics approaches in renal allograft assessment.METHODS A systematic review was conducted in accordance with PRISMA guidelines,based on research results from the PubMed and Scopus databases.The primary focus was on evaluating the role of biomarkers in the non-invasive diagnosis of transplant-related com-plications.Eligibility criteria included protein biomarkers and urine and blood samples,while exclusion criteria were language other than English and the use of low resolution and sensitivity methods.The selected research articles,were categorized based on the biological sample,condition and methodology and the significantly and reproducibly differentiated proteins were manually selected and extracted.Functional and network analysis of the selected proteins was performed.RESULTS In 17 included studies,58 proteins were studied,with the cytokine CXCL10 being the most investigated.Biological pathways related to immune response and fibrosis have shown to be enriched.Applications of biomarkers for the assessment of renal damage as well as the prediction of short-term and long-term function of the graft were reported.Overall,all studies have shown satisfactory diagnostic accuracy of proteins alone or in combination with conventional methods,as far as renal graft assessment is concerned.CONCLUSION Our review suggests that protein biomarkers,evaluated in specific biological fluids,can make a significant contribution to the timely,valid and non-invasive assessment of kidney graft. 展开更多
关键词 PROTEOMICS Kidney transplantation Graft evaluation Non-invasive diagnosis Kidney graft function
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Modeling and performance evaluation of QoS-aware job scheduling of computational grids
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作者 单志广 林闯 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期425-430,共6页
To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated ... To achieve high quality of service (QoS) on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated QoS-aware job dispatching policy is proposed, which correlates priorities of incoming jobs used for job selecting at the local scheduler of the grid node with the job dispatching policies at the global scheduler for computational grids. The stochastic high-level Petri net (SHLPN) model of a two-level hierarchy computational grid architecture is presented, and a model refinement is made to reduce the complexity of the model solution. A performance analysis technique based on the SHLPN is proposed to investigate the QoS-aware job scheduling policy. Numerical results show that the QoS-aware job dispatching policy outperforms the QoS-unaware job dispatching policy in balancing the high-priority jobs, and thus enables priority-based QoS. 展开更多
关键词 computational grids job scheduling quality of service (QoS) performance evaluation MODELING stochastic high-level Petri net (SHLPN)
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Comprehensive Performance Evaluation of Family Farms from the Perspective of Land Transfer——Taking Rudong County as an Example
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作者 孙燕 张云鹏 戴福鑫 《Agricultural Science & Technology》 CAS 2017年第12期2638-2643,共6页
With the reform of agriculture, family farms have become hot spots in the reform of agricultural management system. Taking Rudong County of Jiangsu Province for an example, the land transfer performance of family farm... With the reform of agriculture, family farms have become hot spots in the reform of agricultural management system. Taking Rudong County of Jiangsu Province for an example, the land transfer performance of family farms was evalu- ated using the first hand data from field investigation by building an index system for comprehensive performance evaluation of family farm land transfer covering three dimensions of economy, society and ecology. The results show that land transfer in family farm mode has realized the scale management of land, enhanced the agri- cultural level of science and technology, effectively promoted the structural adjust- ment of agriculture and income increase of farmers, advanced the development of eco-agriculture, and achieved good economic and social performances. However, in the development process of family farms, inputs of agro-chemicals, fertilizers and other agro-products have brought about the eco-environmental problems, which are still worth noting. 展开更多
关键词 Land transfer Comprehensive performance evaluation Family farm Rudong County
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Status analysis on sputtering and erosion evaluation methods of ion optic systems
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作者 Long MIAO Tongxun YANG +3 位作者 Zhengxi ZHU Chang LU Zhiwen WU Ningfei WANG 《Chinese Journal of Aeronautics》 2025年第1期254-270,共17页
In the past few decades,ion engines have been widely used in deep-space propulsion and satellite station-keeping.The aim of extending the thruster lifetime is still one of the most important parts during the design st... In the past few decades,ion engines have been widely used in deep-space propulsion and satellite station-keeping.The aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion engine.As one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming failures.In this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid assembly.The advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are analyzed.Three different types of experimental methods of grid assembly erosion patterns are compared.The analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid assembly.Consequently,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime. 展开更多
关键词 Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation
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Performances and Germplasm Evaluation of Quantitative Resistance to Soybean Mosaic Virus in Soybeans 被引量:15
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作者 ZHIHai-jian GAIJun-yi 《Agricultural Sciences in China》 CAS CSCD 2004年第4期247-253,共7页
A sample composed of 96 soybean accessions was evaluated for their diseased rate (I),diseased rank (S), latent period (LP) and rate of disease development (R) in order tostudy the quantitative resistance to soybean mo... A sample composed of 96 soybean accessions was evaluated for their diseased rate (I),diseased rank (S), latent period (LP) and rate of disease development (R) in order tostudy the quantitative resistance to soybean mosaic virus (SMV) in soybeans. The resultsshowed that the performances of the above four resistance components were significantlydifferent among accessions and that some of the accessions, such as Zhongzihuangdou,Peixian Tianedan, Youbian30 could be infected by four SMV strains, Sa, SC8, N1 and N3,but their I, S, and R were lower and LP longer than most other accessions. These resultsdemonstrated the existence of quantitative resistance to SMV in soybeans. It was foundthat some soybean accessions, such as AGS19 and Lishui Zhongzihuangdou, previouslyidentified as resistant to SMV infection, performed some infection but resistant toexpansion in the present study. In addition, the resistance in Pixian Chadou and HuaiyinQiuheidou might be either qualitative or quantitative. Furthermore, the present studyalso indicated that the resistance spectrum and durability of accessions with quantitativeresistance might be wider and longer than those with qualitative resistance. 展开更多
关键词 Soybean mosaic virus Quantitative resistance Germplasm evaluation
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Performance Evaluation of Urban Comprehensive Carrying Capacity of Harbin, Heilongjiang Province in China 被引量:6
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作者 DIAO Shuo YUAN Jiadong WU Yanyan 《Chinese Geographical Science》 SCIE CSCD 2019年第4期579-590,共12页
Urban comprehensive carrying capacity is an important guarantee and external representation of regional sustainable development. Based on urban comprehensive carrying capacity, this paper constructed a performance eva... Urban comprehensive carrying capacity is an important guarantee and external representation of regional sustainable development. Based on urban comprehensive carrying capacity, this paper constructed a performance evaluation index system of urban comprehensive carrying capacity, and used entropy method, urban comprehensive carrying capacity measurement model and urban sustainable development model to measure spatial and temporal comprehensive carrying capacity of Harbin City in Heilongjiang Province from 2012 to 2017. The results show that: 1) index weight analysis suggested the regional development mode in Harbin still followed an epitaxial development mode, which pursued the expansion of scale and the growth of total amount of regional development, neglecting the effective utilization of resources and the improvement of structural benefits. 2) In the pressure system, the index of resource support has dropped sharply. The index of environmental capacity and social progress has risen circuitously, while the degree of agglomeration and the value of transportation facilities have risen steadily;in the pressure system, the index of population development and economic growth tended to fluctuate, while energy consumption and environmental pollution showed a more synchronous change in characteristics, and the livable demand remained at a high level. 3) The carrying capacity index of resources and environment in Harbin has been declining, and the acquired carrying capacity index fluctuated. The long-term regional development model has severely impaired the carrying capacity of resources and environment. 4) The comprehensive carrying capacity of Harbin has clear spatial differentiation characteristics. Finally, the paper proposes that location conditions, economic development level, government regulation, and science and technology are the main factors influencing the spatial differentiation of urban comprehensive carrying capacity. 展开更多
关键词 COMPREHENSIVE carrying capacity NATURAL carrying capacity performance evaluation influencing FACTORS HARBIN CITY
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Eco-city Planning and Practices from the Perspective of Environmental Performance Evaluation 被引量:3
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作者 CAI Yunnan LIU Chenyi 《Journal of Landscape Research》 2015年第4期49-52,57,共5页
By reviewing researches on environmental performance evaluation of current eco-city construction, this paper analyzed characteristics and deficiencies of the evaluation methods and index systems, and took Haizhu Eco-c... By reviewing researches on environmental performance evaluation of current eco-city construction, this paper analyzed characteristics and deficiencies of the evaluation methods and index systems, and took Haizhu Eco-city for example to assess the environmental performance of eco-city construction from the perspectives of land, water environment, regional weather, and biodiversity. On this basis, a scientific, objective and feasible evaluation method and index system was basically formed so as to demonstrate the efficiency of eco-city construction, and to provide scientific support for the dynamic adjustment and optimization of eco-city construction. 展开更多
关键词 ECO-CITY Environmental performance evaluation evaluation index evaluation method
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Efficient structural seismic performance evaluation method using improved endurance time analysis 被引量:3
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作者 Li Shuang Liu Kun +2 位作者 Liu Xiangyang Zhai Changhai Xie Fengwei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期795-809,共15页
Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dyna... Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dynamic analysis (IDA) method or pushover method. The recently developed endurance time (ET) method is another method that uses dynamic pushover excitations, i.e., endurance time acceleration function, to obtain results similar to those obtained by IDA or pushover methods with low computational cost and acceptable accuracy. This study proposes an improvement on the ET method by considering more restrictions for both the elastic and inelastic response spectra in the generation procedure, and by specifying a target duration. Four reinforced concrete frame structures with 4, 8, 12, and 16 stories are adopted to verify the accuracy of the improved method. Comparison of the results obtained by the proposed method, the ET method and the IDA method shows that the improved method has a higher accuracy than the ET method. For evaluation of structural responses under specifi c ground motion intensity, which is typically required in seismic design codes, the results obtained by the proposed method are compared with fi ve commonly used ground motion selection methods, and shows the proposed method provides acceptable accuracy for engineering applications. 展开更多
关键词 SEISMIC PERFormance evaluation ENDURANCE TIME method INELASTIC response spectra target DURATION
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Dynamical analysis and performance evaluation of a biped robot under multi-source random disturbances 被引量:4
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作者 Chun-Biao Gan Chang-Tao Ding Shi-Xi Yang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第6期983-994,共12页
During bipedal walking,it is critical to detect and adjust the robot postures by feedback control to maintain its normal state amidst multi-source random disturbances arising from some unavoidable uncertain factors.Th... During bipedal walking,it is critical to detect and adjust the robot postures by feedback control to maintain its normal state amidst multi-source random disturbances arising from some unavoidable uncertain factors.The radical basis function(RBF)neural network model of a five-link biped robot is established,and two certain disturbances and a randomly uncertain disturbance are then mixed with the optimal torques in the network model to study the performance of the biped robot by several evaluation indices and a specific Poincar′e map.In contrast with the simulations,the response varies as desired under optimal inputting while the output is fluctuating in the situation of disturbance driving.Simulation results from noise inputting also show that the dynamics of the robot is less sensitive to the disturbance of knee joint input of the swing leg than those of the other three joints,the response errors of the biped will be increasing with higher disturbance levels,and especially there are larger output fluctuations in the knee and hip joints of the swing leg. 展开更多
关键词 Biped robot Multi-source random disturbances Sensitive parameters RBF neural network Taguchi method Performance evaluation
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Review on supercapacitors:Technologies and performance evaluation 被引量:6
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作者 Jingyuan Zhao Andrew F.Burke 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期276-291,I0006,共17页
The development of electrochemical capacitors(i.e.supercapacitors)have attracted a lot of attention in recent years because of the increasing demand for efficient,high-power energy storage.Electrochemical capacitors(E... The development of electrochemical capacitors(i.e.supercapacitors)have attracted a lot of attention in recent years because of the increasing demand for efficient,high-power energy storage.Electrochemical capacitors(ECs)are particularly attractive for transportation and renewable energy generation applications,taking advantage of their superior power capability and outstanding cycle life.Over the past decade,various advanced electrode materials and cell design are being studied to improve the energy density of ECs.Hybrid Li-ion capacitors and pseudo-capacitors that utilize fast surface redox reactions of metal oxide and doped polymers are the prime candidates being considered.This paper is concerned with the metrics being used to describe the performance of ECs and how the metrics are evaluated by testing devices and how the data from the testing are best interpreted.Emphasize is on relating testing of advanced ECs using materials more complex than activated carbons to testing electric double-layer capacitors(EDLCs)using carbon in both electrodes.A second focus of the paper is projecting the potential of the advanced materials and ionic liquid electrolytes for the development of complete EC cells having an energy density more than a factor of ten greater the energy density of the EDLC devices currently on the market.This potential was evaluated by calculating the performance(energy and power)of a series of ECs that utilize the advanced materials that have been studied by electrochemists over the past 10-15 years.The capacitance and resistance of the advanced ECs were calculated utilizing specific capacitance(F/g or F/cm^(3))and porosity data for the electrode materials and ionic conductivity of the electrolytes.It was concluded that hybrid ECs can be developed with energy densities of at least 50 Wh/kg,70 Wh/L with efficient power greater than 3 k W/kg.Continued research on micro-porous carbons with specific capacitance of 200 F/g and greater is needed.to achieve these EC performance goals. 展开更多
关键词 Electrochemical capacitors Metrics evaluation Cell design APPLICATIONS
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Novel Evaluation Method of Vehicle Suspension Performance Based on Concept of Wheel Turn Center 被引量:2
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作者 WANG Bo GUAN Hsin +1 位作者 LU Pingping ZHAN Jun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期935-944,共10页
The current research of suspension performance evaluation is mixed in the evaluation of vehicle handling and ride comfort. However, it is lack of a direct and independent evaluation method for suspension performance. ... The current research of suspension performance evaluation is mixed in the evaluation of vehicle handling and ride comfort. However, it is lack of a direct and independent evaluation method for suspension performance. In this paper, a novel wheel turn center method is proposed to evaluate the suspension performance. This method is based on the concept and application of wheel turn center (WTC) and sprung mass turn center (SPTC). The vehicle body and each wheel are regarded to be independent rigid bodies and have their own turn centers which reflect respective steering motions and responses. Since the suspension is the link between vehicle body and wheels, the consistence between the sprung mass turn center and the wheel turn center reflects the effect and performance of the suspension system. Firstly, the concept and appropriate calculation method of WTC and SPTC are developed. Then the degree of inconsistence between WTC and SPTC and the time that they achieve consistence, when the vehicle experiences from transient steering to steady steering state, are proposed to evaluate suspension performance. The suspension evaluation tests are conducted under different vehicle velocities and lateral accelerations by using CarSim software. The simulation results show that the inconsistence of steering motion between vehicle body and wheels are mainly at high speeds and low lateral accelerations. Finally, based on the proposed evaluation indexes, the influences of different suspension characteristic parameters on suspension performance and their matches to improve steering coordination are discussed. The proposed wheel turn center method provides a guidance and potential application for suspension evaluation and optimization. 展开更多
关键词 SUSPENSION evaluation wheel turn center sprung mass turn center
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Performance Evaluation of China's Agricultural Listed Companies Based on DEA Model 被引量:2
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作者 LUO Hua-wei ,ZHANG Wei School of Economics and Management,Sichuan Agricultural University,Chengdu 611130,China 《Asian Agricultural Research》 2012年第5期1-6,12,共7页
In order to evaluate the performance of China's agricultural listed companies,we analyze the overall efficiency,pure technical efficiency and scale efficiency of China's agricultural listed companies on the ba... In order to evaluate the performance of China's agricultural listed companies,we analyze the overall efficiency,pure technical efficiency and scale efficiency of China's agricultural listed companies on the basis of input-output data concerning 34 agricultural listed companies,using BCC model in data envelopment analysis ( DEA) model. Then we analyze input-output redundancy situation using the slack variable derived from the model. The results show that the overall efficiency of China's agricultural listed companies is good,and the gap in efficiency between sub-industries is small; there is significant difference in performance between listed companies engaged in the same sub-industry,and the reason for invalid DEA in companies within the industry is complex; total assets and asset-liability ratio are high,and the effective output is not fully realized. Finally corresponding recommendations are put forward for promoting the performance of agricultural listed companies as follows: strengthening brand awareness; promoting the level of production technology; adjusting the input structure; transforming the agricultural growth mode. 展开更多
关键词 PERFormance evaluation DEA MODEL AGRICULTURAL LIST
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PERFORMANCE EVALUATION METHOD FOR BUSINESS PROCESS OF MACHINERY MANUFACTURER BASED ON DEA/AHP HYBRID MODEL 被引量:3
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作者 WANG Ting YI Shuping YANG Yuanzhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第3期91-97,共7页
A set of indices for performance evaluation for business processes with multiple inputs and multiple outputs is proposed, which are found in machinery manufacturers. Based on the traditional methods of data envelopmen... A set of indices for performance evaluation for business processes with multiple inputs and multiple outputs is proposed, which are found in machinery manufacturers. Based on the traditional methods of data envelopment analysis (DEA) and analytical hierarchical process (AHP), a hybrid model called DEA/AHP model is proposed to deal with the evaluation of business process performance. With the proposed method, the DEA is firstly used to develop a pairwise comparison matrix, and then the AHP is applied to evaluate the performance of business process using the pairwise comparison matrix. The significant advantage of this hybrid model is the use of objective data instead of subjective human judgment for performance evaluation. In the case study, a project of business process reengineering (BPR) with a hydraulic machinery manufacturer is used to demonstrate the effectiveness of the DEA/AHP model. 展开更多
关键词 Business process Data envelopment analysis(DEA) Analytical hierarchical process(AHP) Hybrid model Performance evaluation
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Application of Fuzzy Comprehensive Evaluation on COGAG Power Plant of Performance 被引量:3
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作者 Menglin Shao Qianchao Liang +2 位作者 Dong Yan Heng Qin Jun Xiang 《Journal of Power and Energy Engineering》 2014年第9期29-34,共6页
A fuzzy comprehensive evaluation of COGAG power plant performance is given by using a method of fuzzy mathematics, and multilevel fuzzy evaluation model is set up. Taking a naval ship as an example, the major paramete... A fuzzy comprehensive evaluation of COGAG power plant performance is given by using a method of fuzzy mathematics, and multilevel fuzzy evaluation model is set up. Taking a naval ship as an example, the major parameters related to COGAG power plant performance are obtained by computer simulation, and a set of synthetic performance evaluation index system is established. The result shows that the strong fuzzy propulsion system performance indexes can be quantified by this fuzzy evaluation model in order to provide the reference for choosing the optimal design of ship propulsion system. 展开更多
关键词 COGAG POWER PLANT FUZZY COMPREHENSIVE evaluation PERFormance INDEX
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