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Performance Evaluation System of Pig Supply Chain Based on Time-Space Perspective and Balanced Score Card(BSC)
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作者 Gao Kuo Gan Xiaoqing 《Animal Husbandry and Feed Science》 CAS 2014年第6期334-341,共8页
The overall structure of live pig supply chain was constructed based on theoretical study and practical investigation, and the performance evaluation sys- tem for supply chain was studied from two perspectives of time... The overall structure of live pig supply chain was constructed based on theoretical study and practical investigation, and the performance evaluation sys- tem for supply chain was studied from two perspectives of time and space and balanced score card (BSC). From the space perspective and BSC, the performance evaluation system composed of four primary indicators (financial dimension, customer dimension, internal business dimension and innovation/learning perspective) and 26 secondary indicators. From the time perspective and BSC, the system could be divided into four stages, including formation stage, development stage, matu- rity stage and recession stage, with a total of 30 indicators. 展开更多
关键词 Pig supply chain performance evaluation TIME SPACE BSC
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Ventilator performance evaluation system based on virtual instruments
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作者 戴文 任旭颖 林青 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期22-25,共4页
A virtual instrument system is proposed to test the performance parameters of local-ventilator installed under coal mines,which can do ventilator parameter acquisition automatically,as well as plot and analyze the ven... A virtual instrument system is proposed to test the performance parameters of local-ventilator installed under coal mines,which can do ventilator parameter acquisition automatically,as well as plot and analyze the ventilator performance curve.The whole system is designed using the virtual instrument technology combined with network technology based on Labview platform.Experimental results show that it can monitor and evaluate ventilator’s performance parameters automatically and efficiently,which provides critical information for ventilator safety under coal mine. 展开更多
关键词 virtual instrument ventilator performance evaluation remote transmission
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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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A general evaluation system for optimal selection performance of radar clutter model
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作者 YANG Wei ZHANG Liang +2 位作者 YANG Liru ZHANG Wenpeng SHEN Qinmu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1520-1525,共6页
The optimal selection of radar clutter model is the premise of target detection,tracking,recognition,and cognitive waveform design in clutter background.Clutter characterization models are usually derived by mathemati... The optimal selection of radar clutter model is the premise of target detection,tracking,recognition,and cognitive waveform design in clutter background.Clutter characterization models are usually derived by mathematical simplification or empirical data fitting.However,the lack of standard model labels is a challenge in the optimal selection process.To solve this problem,a general three-level evaluation system for the model selection performance is proposed,including model selection accuracy index based on simulation data,fit goodness indexs based on the optimally selected model,and evaluation index based on the supporting performance to its third-party.The three-level evaluation system can more comprehensively and accurately describe the selection performance of the radar clutter model in different ways,and can be popularized and applied to the evaluation of other similar characterization model selection. 展开更多
关键词 radar clutter clutter characterization model model selection performance evaluation.
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Performance evaluation of CLM5.0 in simulating liquid soil water in high mountainous area,Northwest China
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作者 ZHANG Lan-hui NING Feng-wei +2 位作者 BAI Xu-liang ZENG Xuan HE Chan-sheng 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1865-1883,共19页
The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) i... The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) in simulating liquid SWC was evaluated against observations from nine in-situ sites in the upper reach of the Heihe River Watershed(HRW),Northwest China.The CLM5.0 shows reliable performance in the study area with correlation coefficients(R) ranging between 0.79–0.93,root mean standard errors(RMSE)ranging between 0.044–0.097 m^(3)/m^(3),and the mean bias(BIAS) ranging between-0.084–0.061 m^(3)/m^(3).The slightly worse performance of CLM5.0 than CLM4.5 on alpine meadow and grassland is mainly caused by the revised canopy interception parameterization.The CLM5.0 overestimates interception and underestimates evapotranspiration(ET) on both alpine meadow and grassland during the growth period.The systematical overestimations at all the grassland sites indicate that the underestimation of ET is much larger than the overestimation of interception on grassland during growth period,while the errors of simulated interception and ET are partially canceled out on alpine meadow.Moreover,the underestimation of ET is more responsible for the overestimation of SWC than the overestimation of interception in the high mountainous area.It is necessary to estimate reasonable empirical parameter α(proportion of leaf water collection area) in interception parameterization scheme and further improve the dry surface layerbased soil evaporation resistance parameterization introduced in CLM5.0 in future researches.The performance of CLM5.0 is better under completely frozen stage than thawing stage and freezing stage,because of low variations of liquid SWC caused by extremely low hydraulic conductivity of soils.The underestimation of liquid SWC under frozen state is caused by underestimation of soil temperature,which leads to more ice mass and less liquid water in total water content. 展开更多
关键词 performance evaluation Soil water content CLM5.0 EVAPOTRANSPIRATION High mountainous area
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Carbon materials toward efficient potassium storage:Rational design,performance evaluation and potassium storage mechanism
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作者 Daping Qiu Yanglong Hou 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期115-140,共26页
Potassium-ion batteries(PIBs)are potential“Beyond Li-ion Batteries”candidates for their resource advantage and low standard electrode potential.To date,the research on PIBs is in its early stages,the most urgent tas... Potassium-ion batteries(PIBs)are potential“Beyond Li-ion Batteries”candidates for their resource advantage and low standard electrode potential.To date,the research on PIBs is in its early stages,the most urgent task is to develop high-performance electrode materials and reveal their potassium storage mechanism.For PIBs anode materials,carbon with tunable microstructure,excellent electrochemical activity,nontoxicity and low price is considered as one of the most promising anode materials for commercialization.Although some breakthrough works have emerged,the overall electrochemical performance of the reported carbon anode is still far away from practical application.Herein,we carry out a comprehensive overview of PIBs carbon anode in terms of three aspects of rational design of structure,performance evaluation criteria and characterization of potassium storage mechanism.First,the regulation mechanism of key structural features of carbon anode on its potassium storage performance and the representative structural regulation strategies are introduced.Then,in view of the undefined performance evaluation criteria of PIBs carbon anode,a reference principle for evaluating the potassium storage performance of carbon anode is proposed.Finally,the advanced characterization techniques for the potassium storage mechanism of carbon anode are summarize.This review aims to provide guidance for the development of practical PIBs anode. 展开更多
关键词 Potassium-ion batteries Carbon anode Structural engineering performance evaluation Potassium storage mechanism
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ROS2 Real-time Performance Optimization and Evaluation
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作者 Yanlei Ye Zhenguo Nie +3 位作者 Xinjun Liu Fugui Xie Zihao Li Peng Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期36-50,共15页
Real-time interaction with uncertain and dynamic environments is essential for robotic systems to achieve functions such as visual perception,force interaction,spatial obstacle avoidance,and motion planning.To ensure ... Real-time interaction with uncertain and dynamic environments is essential for robotic systems to achieve functions such as visual perception,force interaction,spatial obstacle avoidance,and motion planning.To ensure the reliability and determinism of system execution,a flexible real-time control system architecture and interaction algorithm are required.The ROS framework was designed to improve the reusability of robotic software development by providing a distributed structure,hardware abstraction,message-passing mechanism,and application prototypes.Rich ecosystems for robotic development have been built around ROS1 and ROS2 architectures based on the Linux system.However,because of the fairness scheduling principle of the default Linux system design and the complexity of the kernel,the system does not have real-time computing.To achieve a balance between real-time and non-real-time computing,this paper uses the transmission mechanism of ROS2,combines it with the scheduling mechanism of the Linux operating system,and uses Preempt_RT to enhance the real-time computing of ROS1 and ROS2.The real-time performance evaluation of ROS1 and ROS2 is conducted from multiple perspectives,including throughput,transmission mode,QoS service quality,frequency,number of subscription nodes and EtherCAT master.This paper makes two significant contributions:firstly,it employs Preempt_RT to optimize the native ROS2 system,effectively enhancing the real-time performance of native ROS2 message transmission;secondly,it conducts a comprehensive evaluation of the real-time performance of both native and optimized ROS2 systems.This comparison elucidates the benefits of the optimized ROS2 architecture regarding real-time performance,with results vividly demonstrated through illustrative figures. 展开更多
关键词 ROS Real-time system optimization Preempt_RT Real-time performance evaluation of ROS2
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Recent Advances in the Rapid Detection and Performance Evaluation Methods of Detergent Additives for Gasoline
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作者 Zhi Wanwan Li Na +2 位作者 Zhu Zhongpeng Li Yan Guo Xin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第2期165-176,共12页
Although detergent additives for gasoline have been widely commercialized,their formulas are often kept confidential and there is still no standardized method for quickly detecting the main active ingredients and eval... Although detergent additives for gasoline have been widely commercialized,their formulas are often kept confidential and there is still no standardized method for quickly detecting the main active ingredients and evaluating their effectiveness,which makes their regulation difficult.An overview of the current state of the development and application of detergent additives for gasoline in China and other regions,as well as a review of the rapid detection and performance evaluation methods available for analyzing detergent additives are given herein.The review focuses on the convenience,cost,efficiency,and feasibility of on-site detection and the evaluation of various methods,and also looks into future research directions,such as detecting and evaluating detergent additives in ethanol gasoline and with advanced engine technologies. 展开更多
关键词 GASOLINE detergent additives DEPOSITS rapid detection performance evaluation
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Flow control performance evaluation of a tri-electrode sliding discharge plasma actuator
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作者 郑博睿 刘园鹏 +3 位作者 喻明浩 金元中 张倩 陈全龙 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期348-355,共8页
Tri-electrode sliding discharge(TED)plasma actuators are formed by adding a direct current(DC)exposed electrode to conventional dielectric barrier discharge(DBD)plasma actuators.There are three TED modes depending on ... Tri-electrode sliding discharge(TED)plasma actuators are formed by adding a direct current(DC)exposed electrode to conventional dielectric barrier discharge(DBD)plasma actuators.There are three TED modes depending on the polarity and amplitude of the DC supply:DBD discharge,extended discharge and sliding discharge.This paper evaluates the electrical,aerodynamic and mechanical characteristics of a TED plasma actuator based on energy analysis,particle image velocimetry experiments and calculations using the Navier-Stokes equation.The flow control performances of different discharge modes are quantitatively analyzed based on characteristic parameters.The results show that flow control performance in both extended discharge and sliding discharge is more significant than that of DBD,mainly because of the significantly higher(up to 141%)body force of TED compared with DBD.However,conductivity loss is the primary power loss caused by the DC polarity for TED discharge.Therefore,power consumption can be reduced by optimizing the dielectric material and thickness,thus improving the flow control performance of plasma actuators. 展开更多
关键词 plasma flow control tri-electrode sliding discharge particle image velocimetry(PIV) performance evaluation
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Comprehensive review and performance evaluation of maximum power point tracking algorithms for photovoltaic system 被引量:3
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作者 Asegid Belay Kebede Getachew Biru Worku 《Global Energy Interconnection》 2020年第4期398-412,共15页
A photovoltaic array is environmentally friendly and a source of unlimited energy generation.However,it is presently a costlier energy generation system than other non-renewable energy sources.The main reasons are sea... A photovoltaic array is environmentally friendly and a source of unlimited energy generation.However,it is presently a costlier energy generation system than other non-renewable energy sources.The main reasons are seasonal variations and continuously changing weather conditions,which affect the amount of solar energy received by the solar panels.In addition,the non-linear characteristics of the voltage and current outputs along with the operating environment temperature and variation in the solar radiation decrease the energy conversion capability of the photovoltaic arrays.To address this problem,the global maxima of the PV arrays can be tracked using a maximum power point tracking algorithm(MPPT)and the operating point of the photovoltaic system can be forced to its optimum value.This technique increases the efficiency of the photovoltaic array and minimizes the cost of the system by reducing the number of solar modules required to obtain the desired power.However,the tracking algorithms are not equally effective in all areas of application.Therefore,selecting the correct MPPT is very critical.This paper presents a detailed review and comparison of the MPPT techniques for photovoltaic systems,with consideration of the following key parameters:photovoltaic array dependence,type of system(analog or digital),need for periodic tuning,convergence speed,complexity of the system,global maxima,implemented capacity,and sensed parameter(s).In addition,based on real meteorological data(irradiance and temperature at a site located in Addis Ababa,Ethiopia),a simulation is performed to evaluate the performance of tracking algorithms suitable for the application being studied.Finally,the study clearly validates the considerable energy saving achieved by using these algorithms. 展开更多
关键词 Maximum power point tracking system PHOTOVOLTAIC Renewable energy performance evaluation system efficiency
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Performance evaluation of ecological compensation policy for cultivated land in China
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作者 ZHANG Yue-sheng TAN Yu-xuan 《Ecological Economy》 2023年第1期44-62,共19页
The paper evaluates the changes in the ecological environment of cultivated land in the major crop-producing areas major crop-producing areas in the past 20 years by constructing an ecological pollution index;and quan... The paper evaluates the changes in the ecological environment of cultivated land in the major crop-producing areas major crop-producing areas in the past 20 years by constructing an ecological pollution index;and quantitatively analyzes the effects of the existing policies and their main influencing factors by applying the PSM-DID method based on the frequency of policy enactment.The results are as follows:first,the existing ecological compensation policies for cultivated land are effective but not significant in improving the ecological environment in the major crop-producing areas.The economic development level and grain cultivation area of the major crop-producing areas are significantly and positively correlated with the improvement of the arable land ecological environment,while the level of agricultural infrastructure construction is significantly and negatively correlated with the improvement of the arable land ecological environment.Second,the reason for the ineffectiveness of the current arable ecological land compensation policy in protecting the arable land ecological environment in the main grain-producing regions is that the existing arable ecological land compensation policy in China has its own institutional defects and needs to be further improved.At the same time,the level of environmental pollution of cultivated land in the main grain-producing regions is positively correlated with the level of income from cultivated land and cultivated area. 展开更多
关键词 cultivated land ecological compensation performance evaluation major grain producing areas
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A multi-feature-based intelligent redundancy elimination scheme for cloud-assisted health systems
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作者 Ling Xiao Beiji Zou +4 位作者 Xiaoyan Kui Chengzhang Zhu Wensheng Zhang Xuebing Yang Bob Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第2期491-510,共20页
Redundancy elimination techniques are extensively investigated to reduce storage overheads for cloud-assisted health systems.Deduplication eliminates the redundancy of duplicate blocks by storing one physical instance... Redundancy elimination techniques are extensively investigated to reduce storage overheads for cloud-assisted health systems.Deduplication eliminates the redundancy of duplicate blocks by storing one physical instance referenced by multiple duplicates.Delta compression is usually regarded as a complementary technique to deduplication to further remove the redundancy of similar blocks,but our observations indicate that this is disobedient when data have sparse duplicate blocks.In addition,there are many overlapped deltas in the resemblance detection process of post-deduplication delta compression,which hinders the efficiency of delta compression and the index phase of resemblance detection inquires abundant non-similar blocks,resulting in inefficient system throughput.Therefore,a multi-feature-based redundancy elimination scheme,called MFRE,is proposed to solve these problems.The similarity feature and temporal locality feature are excavated to assist redundancy elimination where the similarity feature well expresses the duplicate attribute.Then,similarity-based dynamic post-deduplication delta compression and temporal locality-based dynamic delta compression discover more similar base blocks to minimise overlapped deltas and improve compression ratios.Moreover,the clustering method based on block-relationship and the feature index strategy based on bloom filters reduce IO overheads and improve system throughput.Experiments demonstrate that the proposed method,compared to the state-of-the-art method,improves the compression ratio and system throughput by 9.68%and 50%,respectively. 展开更多
关键词 big data cloud computing compression data compression medical applications performance evaluation
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Analysis of Highway Roadbed Performance Evaluation Technology
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作者 Yunyong Zhou Ke Tu +2 位作者 Daqing Wu Shuyan Liu Yingying Ye 《Journal of World Architecture》 2023年第2期36-40,共5页
With the continuous development of China,the requirements for road construction are also increasing.Among them,strengthening the performance of roadbed test can effectively improve road construction.Besides,it is also... With the continuous development of China,the requirements for road construction are also increasing.Among them,strengthening the performance of roadbed test can effectively improve road construction.Besides,it is also crucial to perform suitable tests in a timely manner.Therefore,highway inspection technology should be improved for the continuous development of highway construction,which will be explained in this paper,in hopes of improving the construction of highway in China. 展开更多
关键词 Highway roadbed performance evaluation Testing technology
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DYNAMIC MATHEMATICAL MODELING AND APPLICATION FOR PUMPING SYSTEM PERFORMANCE INTEGRATED EVALUATION
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作者 ChenHongxun WangJian WuYuejun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第3期285-288,共4页
A mathematical model is set to evaluate the overall centrifugal pumpingsystem using asynchronous motor as power. This method can be used to affirm system performanceaccording the transform and the aberrance of interio... A mathematical model is set to evaluate the overall centrifugal pumpingsystem using asynchronous motor as power. This method can be used to affirm system performanceaccording the transform and the aberrance of interior parameters and exterior performance curves soas to give a reference to the equipment amelioration. The analysis of emulation experiment datasuggests the model is effectively used. 展开更多
关键词 Pumping system Mathematical model performance evaluation
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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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Performance Evaluation of Public Bus Transportation by Using DEA Models and Shannon’s Entropy:An Example From a Company in a Large City of China 被引量:4
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作者 Zicheng Liu Naiqi Wu +1 位作者 Yan Qiao Zhiwu Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期779-795,共17页
The purpose of this paper is to assess the operational efficiency of a public bus transportation via a case study from a company in a large city of China by using data envelopment analysis(DEA)model and Shannon’s ent... The purpose of this paper is to assess the operational efficiency of a public bus transportation via a case study from a company in a large city of China by using data envelopment analysis(DEA)model and Shannon’s entropy.This company operates 37 main routes on the backbone roads.Thus,it plays a significant role in public transportation in the city.According to bus industry norms,an efficiency evaluation index system is constructed from the perspective of both company operations and passenger demands.For passenger satisfaction,passenger waiting time and passenger-crowding degree are considered,and they are undesirable indicators.To describe such indicators,a superefficient DEA model is constructed.With this model,by using actual data,efficiency is evaluated for each bus route.Results show that the DEA model with Shannon’s entropy being combined achieves more reasonable results.Also,sensitivity analysis is presented.Therefore,the results are meaningful for the company to improve its operations and management. 展开更多
关键词 performance evaluation public transportation system Shannon’s entropy super-efficiency data envelopment analysis undesirable outputs
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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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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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Objective Performance Evaluation of Video Segmentation Algorithms with Ground-Truth 被引量:1
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作者 杨高波 张兆扬 《Journal of Shanghai University(English Edition)》 CAS 2004年第1期70-74,共5页
While the development of particular video segmentation algorithms has attracted considerable research interest, relatively little effort has been devoted to provide a methodology for evaluating their performance. In t... While the development of particular video segmentation algorithms has attracted considerable research interest, relatively little effort has been devoted to provide a methodology for evaluating their performance. In this paper, we propose a methodology to objectively evaluate video segmentation algorithm with ground-truth, which is based on computing the deviation of segmentation results from the reference segmentation. Four different metrics based on classification pixels, edges, relative foreground area and relative position respectively are combined to address the spatial accuracy. Temporal coherency is evaluated by utilizing the difference of spatial accuracy between successive frames. The experimental results show the feasibility of our approach. Moreover, it is computationally more efficient than previous methods. It can be applied to provide an offline ranking among different segmentation algorithms and to optimally set the parameters for a given algorithm. 展开更多
关键词 video object segmentation performance evaluation MPEG-4.
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Reservoir water effects on earthquake performance evaluation of Torul Concrete-Faced Rockfill Dam
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作者 Alemdar BAYRAKTAR Murat Emre KARTAL Hasan Basri BASAGA 《Water Science and Engineering》 EI CAS 2009年第1期43-57,共15页
This study presents earthquake performance analysis of the Torul Concrete-Faced Rockfill (CFR) Dam with two-dimensional dam-soil and dam-soil-reservoir finite element models. The Lagrangian approach was used with fl... This study presents earthquake performance analysis of the Torul Concrete-Faced Rockfill (CFR) Dam with two-dimensional dam-soil and dam-soil-reservoir finite element models. The Lagrangian approach was used with fluid elements to model impounded water. The interface elements were used to simulate the slippage between the concrete face slab and the rockfill. The horizontal component of the 1992 Erzincan earthquake, with a peak ground acceleration of 0.515g, was considered in time-history analysis. The Drucker-Prager model was preferred in nonlinear analysis of the concrete slab, rockfill and foundation soil. The maximum principal stresses and the maximum displacements in two opposite directions were compared by the height of the concrete slab according to linear time-history analysis to reveal the effect of reservoir water. The changes of critical displacements and principal stresses with time are also shown in this paper. According to linear and nonlinear time-history analysis, the effect of the reservoir water on the earthquake performance of the Torul CFR Dam was investigated and the possible damage situation was examined. The results show that the hydrodynamic pressure of reservoir water leads to an increase in the maximum displacements and principal stresses of the dam and reduces the earthquake performance of the dam. Although the linear time-history analysis demonstrates that the earthquake causes a momentous damage to the concrete slab of the Torul CFR Dam, the nonlinear time-history analysis shows that no evident damage occurs in either reservoir case. 展开更多
关键词 earthquake performance evaluation concrete-faced rockfill dam dam-soil-reservoir interaction Drucker-Prager model interface element Lagrangian approach nonlinear time-history analysis
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