检索结果-南通市图书馆

Structural Durability & Health Monitoring 2025年第2期19卷 399-415页

作者： Menghui Hao Shanshan Zhou Yongchao Han Zhanwei Zhu Qiang Yang Panxu Sun Jiajun Fan Henan Zhonggong Design&Research Group Co. Ltd.Zhengzhou450000China School of Civil Engineering Zhengzhou UniversityZhengzhou450001China

As an evaluation index,the natural frequency has the advantages of easy acquisition and quantitative *** this paper,the natural frequency is used to evaluate the performance of external cable reinforced *** 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 *** damaged bridges,as the damage to the T-beam increases,the natural frequency value of the bridge gradually *** the degree of local damage to the beam reaches 60%,the amplitude of natural frequency change exceeds 10%for the first *** 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 *** 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 *** 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.

关键词： performance evaluation natural frequency T-beam bridge damage external cable reinforcement

performance evaluation and Optimization of Hierarchical Routing in SDN Control Plane

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2018年第2期27卷 342-350页

作者： HU Jie LIN Chuang ZHANG Puheng Department of Computer Science and Technology Tsinghua University

In Software defined networking(SDN), distributed control plane is becoming a promising solution to tackle with scalability and performance. We propose a tree-like hierarchical routing architecture which employs the divide-and-conquer strategy to enhance routing performance on the distributed control plane. To evaluate and optimize the performance of the hierarchical architecture,we apply queuing theory to modeling routing request arrival and processing, and derive an explicit expression of the routing response time. Then we formulate the resource allocation problem in the hierarchical architecture as an optimization problem whose objective is to minimize the response time subject to queue stability and resource constraints. Using the Karush-Kuhn-Tucker(KKT) condition we obtain the optimal resource allocation policy. Based on that, we theoretically prove that the response time under the hierarchical routing architecture is strictly less than that under the Peer to peer(P2 P) architecture. Finally,we perform numerical analyses to confirm the conclusions.

关键词： Software defined networking(SDN) Control plane Routing performance evaluation Resource allocation

performance evaluation of complex systems using evidential reasoning approach with uncertain parameters

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2021年第1期34卷 194-208页

作者： Leiyu CHEN Zhijie ZHOU Changhua HU Ruihua YUE Zhichao FENG High-Tech Institute of Xi’an Xi’an 710025China Harbin Institute of Technology Harbin 150001China

The composition of the modern aerospace system becomes more and more *** performance degradation of any device in the system may cause it difficult for the whole system to keep normal working ***,it is essential to evaluate the performance of complex aerospace *** this paper,the performance evaluation of complex aerospace systems is regarded as a Multi-Attribute Decision Analysis(MADA)*** on the structure and working principle of the system,a new Evidential Reasoning(ER)based approach with uncertain parameters is proposed to construct a nonlinear optimization model to evaluate the system *** the model,the interval form is used to express the uncertainty,such as error in testing data and inaccuracy in expert *** order to analyze the subsystems that have a great impact on the performance of the system,the sensitivity analysis of the evaluation result is carried out,and the corresponding maintenance strategy is *** a type of Inertial Measurement Unit(IMU)used in a rocket,the proposed method is employed to evaluate its ***,the parameter sensitivity of the evaluation result is analyzed,and the main factors affecting the performance of IMU are ***,the comparative study shows the effectiveness of the proposed method.

关键词： Complex systems Evidential reasoning approach Interval value performance evaluation Uncertain parameters

performance evaluation of a micro turbo-expander for application in low-temperature solar electricity generation

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 207-213页

作者： Gang PEI Yun-zhu LI Jing LI Jie JI Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei 230026 China

A micro turbo-expander capable of high working speed was specially manufactured for use in an organic Rankine cycle (ORC).A series of tests were executed to examine the performance of the *** the experiment,the machine was tested under different inlet pressure conditions (0.2-0.5 MPa).Data such as the compressed air pressure,temperatures of the inlet and the outlet,rotational speed,and electric power generation were analyzed to discover underlying *** the test,the rotational speed of the machine reached as high as 54 000 r/min,the peak value of the temperature drop between the inlet and the outlet reached 42 ℃,the maximum electric power generated by the motor-generator attached to the machine reached 630 W,and the efficiency of the machine reached 0.43.

关键词： Turbo-expander Solar Low-temperature performance evaluation

performance evaluation of Memory-Centric ARMv8 Many-Core Architectures:A Case Study with Phytium 2000+

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2021年第1期36卷 33-43页

作者： Jian-Bin Fang Xiang-Ke Liao Chun Huang De-Zun Dong College of Computer National University of Defense TechnologyChangsha 410073China

This article presents a comprehensive performance evaluation of Phytium 2000+,an ARMv8-based 64-core *** focus on the cache and memory subsystems,analyzing the characteristics that impact the high-performance computing *** provide insights into the memory-relevant performance behaviours of the Phytium 2000+system through *** the help of the well-known roofline model,we analyze the Phytium 2000+system,taking both memory accesses and computations into *** on the knowledge gained from these micro-benchmarks,we evaluate two applications and use them to assess the capabilities of the Phytium 2000+*** results show that the ARMv8-based many-core system is capable of delivering high performance for a wide range of scientific kernels.

关键词： many-core architecture memory-centric design performance evaluation

performance evaluation for multi-target tracking with temporal dimension specifics

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第2期37卷 446-458页

作者： Zhenzhen SU Hongbing JI Cong TIAN Yongquan ZHANG School of Computer Science and Technology Xidian UniversityXi’an 710071China School of Electronic Engineering Xidian UniversityXi’an 710071China

With the great development of Multi-Target Tracking(MTT)technologies,many MTT algorithms have been proposed with their own advantages and *** to the fact that requirements to MTT algorithms vary from the application scenarios,performance evaluation is significant to select an appropriate MTT algorithm for the specific application *** this paper,we propose a performance evaluation method on the sets of trajectories with temporal dimension specifics to compare the estimated trajectories with the true *** proposed method evaluates the estimate results of an MTT algorithm in terms of tracking accuracy,continuity and ***,its computation is based on a multi-dimensional assignment problem,which is formulated as a computable form using linear *** enhance the influence of recent estimated states of the trajectories in the evaluation,an attention function is used to reweight the trajectory errors at different time ***,simulation results show that the proposed performance evaluation method is able to evaluate many aspects of the MTT *** evaluations are worthy for selecting suitable MTT algorithms in different application scenarios.

关键词： Multi-target tracking Temporal dimension specifics performance evaluation Random finite sets Linear programming

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

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2021年第4期8卷 779-795页

作者： Zicheng Liu Naiqi Wu Yan Qiao Zhiwu Li Institute of Systems Engineering and the Collaborative Laboratory for Intelligent Science and Systems Macao University of Science and TechnologyMacaoChina Institute of Systems Engineering and the Collaborative Laboratory for Intelligent Science and Systems Macao University of Science and Technologyand also with the State Key Laboratory of Precision Electronic Manufacturing Technology and EquipmentGuangdong University of TechnologyGuangzhou 510006China

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 *** company operates 37 main routes on the backbone ***,it plays a significant role in public transportation in the *** to bus industry norms,an efficiency evaluation index system is constructed from the perspective of both company operations and passenger *** passenger satisfaction,passenger waiting time and passenger-crowding degree are considered,and they are undesirable *** describe such indicators,a superefficient DEA model is *** this model,by using actual data,efficiency is evaluated for each bus *** show that the DEA model with Shannon’s entropy being combined achieves more reasonable ***,sensitivity analysis is ***,the results are meaningful for the company to improve its operations and management.

关键词： performance evaluation public transportation system Shannon’s entropy super-efficiency data envelopment analysis undesirable outputs

performance evaluation of Advanced Wave Energy Converters in the Nearshore Areas of the North Indian Ocean

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2022年第6期36卷 980-993页

作者： WAN Yong ZHANG Wen FAN Chen-qing LI Li-gang DAI Yong-shou The College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China The Laboratory of Physical Oceanography and Remote Sensing The First Institute of OceanographySOAQingdao 266061China

The 21st Century Maritime Silk Road is a profound measure for mankind,whilst its development is severely restricted by the energy shortage of surrounding *** the core construction area of Maritime Silk Road,the North Indian Ocean is rich in wave *** development and utilization of wave energy not only can overcome energy shortage,but also promote communication between peripheral ***,previous researchers often focused on wave energy itself,without combining devices to analyze wave energy ***,we conducted an overall assessment of wave energy resources using 20-year ERA5 data and determined the sites considered as superior for the construction of Wave Energy Farm(WEF)in the coastal *** order to point out which type of Wave Energy Converter(WEC)is best suited for the sites,we carried out the performance evaluation of eight advanced WECs using three parameters:the mean power output,the capacity factor and the capture width *** results show that the performance of Wave Star is superior to other devices,which is supposed to be the primary consideration of the Wave Energy Farms(WEFs)in the future.

关键词： ocean energy wave energy characteristics site selection wave energy converter performance evaluation

performance evaluation of anti-radiation based on the gamma degradation process

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2017年第4期60卷 501-509页

作者： SONG BingHua ZHOU ZhongBao MA ChaoQun JIN Guang GENG ShaoFeng School of Business Administration Hunan University Changsha 410082 China College of Information System and Management National University of Defense Technology Changsha 410073 China College of Computer Science and Electronic Engineering Hunan University Changsha 410082 China

In the environment of space radiation, the high-energy charged particles or high-energy photons acting on a spacecraft can cause either temporary device degradation or permanent failure. The traditional probability model is difficult to obtain reliable estimation of unit radiation resistance performance with small samples. Considering that different products will change differently after high-energy particle radiation, we construct a model based on the gamma degradation process. This model can efficiently describe the law of unit radiation resistance variation with the total radiation dose levels under the effect of the total dose and displacement damage. Finally, the proposed model is used to assess the anti-radiation performance of the N-channel power MOSFET device STRH60N20FSY3 produced by STM to obtain average unit radiation resistance, survival probability, survival function, etc.

关键词： performance evaluation unit radiation resistance gamma degradation process survival probability

performance evaluation Method for Automated Driving System in Logical Scenario

在线全文

学校读者我要写书评

暂无评论

Automotive Innovation 2022年第3期5卷 299-310页

作者： Peixing Zhang Bing Zhu Jian Zhao Tianxin Fan Yuhang Sun State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchunChina

With the continuous improvement of automated driving technology,how to evaluate the performance of an automated driving system is attracting more and more ***,with the creation of scenario-based test methods,the traditional evaluation index based on a single test can no longer meet the requirements of high-level safety verification for automated driving system,and the performance evaluation of such a system in logical scenarios will be the *** on the scenario-based test method and Turing test theory,a performance evaluation method for an automated driving system in the whole parameter space of a logical scenario is *** logical scenario parameter space is partitioned according to the risk degree of concrete scenario,and the evaluation process in different zones are ***,the anthropo-morphic index in the safe zone and the collision-avoidance index in the danger zone are defined by comparing test results of human driving and ideal vehicle *** front vehicle low-speed and cut-out scenarios as examples,two automated driving algorithms are tested in the virtual environment,and the test results are evaluated both by the proposed method and by human *** results show that the results of the proposed method are consistent with the subjective feelings of humans;additionally,it can be applied to scenario-based tests and the verification process of an automated driving system.

关键词： Automated driving system Logical scenario performance evaluation Anthropomorphic index