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Optimal Design of Multiple Stress Constant Accelerated Life Test Plan on Non-rectangle Test Region 被引量:8
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作者 CHEN Wenhua GAO Liang +2 位作者 LIU Juan QIAN Ping PAN Jun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1231-1237,共7页
For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT desig... For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT design on non-rectangle test region, the present method is only focused on non-rectangle test region with simple boundary, and the optimization algorithm is based on experience which can not ensure to obtain the optimal plan. In this paper, considering the linear-extreme value model and the optimization goal to minimize the variance of lifetime estimate under normal stress, the optimal design method of two-stress type-I censored CSALT plan on general non-rectangular test region is proposed. First, two properties of optimal test plans are proved and the relationship of all the optimal test plans is determined analytically. Then, on the basis of the two properties, the optimal problem is simplified and the optimal design method of two-stress CSALT plan on general non-rectangular test region is proposed. Finally, a numerical example is used to illustrate the feasibility and effectiveness of the method, The result shows that the proposed method could obtain the optimal test plan on non-rectangular test regions with arbitrary boundaries. This research provides the theory and method for two-stress optimal CSALT planning on non-rectangular test regions. 展开更多
关键词 accelerated life test non- rectangular test region test plan optimal design
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Design of Accelerated Life Test Plans——Overview and Prospect 被引量:7
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作者 Wen-Hua Chen Liang Gao +2 位作者 Jun Pan Ping Qian Qing-Chuan He 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第1期19-33,共15页
Accelerated life test(ALT) is currently the main method of assessing product reliability rapidly, and the design of efficient test plans is a critical step to ensure that ALTs can assess the product reliability accura... Accelerated life test(ALT) is currently the main method of assessing product reliability rapidly, and the design of efficient test plans is a critical step to ensure that ALTs can assess the product reliability accurately, quickly, and economically. With the promotion of the national strategy of civil-military integration, ALT will be widely used in the research and development(R&D) of various types of products, and the ALT plan design theory will face further challenges. To aid engineers in selecting appropriate theories and to stimulate researchers to develop the theories required in engineering, with focus on the demands for theory research that arise from the implementation of ALT, this paper reviews and summarizes the development of ALT plan design theory. The development of the theory and method for planning optimal ALT for location-scale distribution, which is the most applied and mature theory of designing the optimal ALT plan, are described in detail. Taking this as the center of radiation, some problems that ALT now faces, such as the verification of the statistical model, limitation of sample size, solutions of resource limits, optimization of the test arrangement, and management of product complexity, are discussed, and the general ideas and methods of solving these problems are analyzed. Suggestions for selecting appropriate ALT plan design theories are proposed, and the urgent solved theory problems and opinions of their solutions are proposed. Based on the principle of convenience for engineers to select appropriate methods according to the problems found in practice, this paper reviews the development of optimal ALT plan design theory by taking the engineering problems arising from the ALT implementation as the main thread, provides guidelines on selecting appropriate theories for engineers, and proposes opinions about the urgent solved theory problems for researchers. 展开更多
关键词 Accelerated life test test plan Optimal design Reliability assessment
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Optimal Design of Multiple Stresses Accelerated Life Test Plan Based on Transforming the Multiple Stresses to Single Stress 被引量:4
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作者 GAO Liang CHEN Wenhua +2 位作者 QIAN Ping PAN Jun HE Qingchuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1125-1132,共8页
For planning optimum multiple stresses accelerated life test plans, a commonly followed guiding principle is that all parameters of the life-stress relationship should be estimated, and the number of the stress level ... For planning optimum multiple stresses accelerated life test plans, a commonly followed guiding principle is that all parameters of the life-stress relationship should be estimated, and the number of the stress level combinations must be no less than the number of parameters of the life-stress relationship. However, the general objective of an accelerated life test(ALT) is to assess thep-th quantile of the product life distribution under normal stress. For this objective,estimating all model parameters is not necessary, and this will increase the cost of test. Based on the theoretical conclusion that the stress level combinations of the optimum multiple stresses ALT plan locate on a straight line through the origin of coordinate, it is proposed that a design idea of planning the optimum multiple stresses ALT plan through transforming the problem of designing an optimum multiple stresses ALT plan to designing an optimum single stress ALT plan. Moreover, a method of planning the optimum multiple stresses ALT plan which can avoid estimating all model parameters is established. An example shows that, the proposed plan which only has two stress level combinations could achieve an accuracy no less than the traditional plan, and save the test time and cost on one stress level combination at least; when the actual product life is less than the design value, even the deviation of the model initial parameters value is up to 20%, the variance of the estimation of thep-th quantile of the proposed plan is still smaller than the traditional plans approximately 25%. A design method is provided for planning the optimum multiple stresses ALT which uses the statistical optimum degenerate test plan as the optimum multiple stresses accelerated life test plan. 展开更多
关键词 multiple stresses accelerated testing optimum design test planning
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Optimum design of equivalent accelerated life testing plans based on proportional hazards-proportional odds model 被引量:3
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作者 Tingting Huang Tongmin Jiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第5期871-878,共8页
The optimum design of equivalent accelerated life testing plan based on proportional hazards-proportional odds model using D-optimality is presented. The defined equivalent test plan is the test plan that has the same... The optimum design of equivalent accelerated life testing plan based on proportional hazards-proportional odds model using D-optimality is presented. The defined equivalent test plan is the test plan that has the same value of the determinant of Fisher information matrix. The equivalent test plan of step stress accelerated life testing (SSALT) to a baseline optimum constant stress accelerated life testing (CSALT) plan is obtained by adjusting the censoring time of SSALT and solving the optimization problem for each case to achieve the same value of the determinant of Fisher information matrix as in the baseline optimum CSALT plan. Numer- ical examples are given finally which demonstrate the equivalent SSALT plan to the baseline optimum CSALT plan reduces almost half of the test time while achieving approximately the same estimation errors of model parameters. 展开更多
关键词 equivalent test plan proportional hazards-proportional odds (PH-PO) model D-OPTIMALITY constant stress step stress accelerated life testing (ALT).
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Planning failure-censored constant-stress partially accelerated life test 被引量:3
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作者 Ali A.Ismail Abdulhakim A.Al-Babtain 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期644-650,共7页
This article deals with the case of the failure-censored constant-stress partially accelerated life test (CSPALT) for highly reliable materials or products assuming the Pareto distribution of the second kind. The ma... This article deals with the case of the failure-censored constant-stress partially accelerated life test (CSPALT) for highly reliable materials or products assuming the Pareto distribution of the second kind. The maximum likelihood (ML) method is used to estimate the parameters of the CSPALT model. The performance of ML estimators is investigated via their mean square error. Also, the average confidence interval length (IL) and the associated co- verage probability (CP) are obtained. Moreover, optimum CSPALT plans that determine the optimal proportion of the test units al- located to each stress are developed. Such optimum test plans minimize the generalized asymptotic variance (GAV) of the ML estimators of the model parameters. For illustration, Monte Carlo simulation studies are given and a real life example is provided. 展开更多
关键词 reliability confidence intervals coverage probabilities optimum test plans Type-Ⅱ censoring Monte Carlo simulation.
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A Planning Method for Operational Test of UAV Swarm Based on Mission Reliability 被引量:2
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作者 Jingyu Wang Ping Jiang Jianjun Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1889-1918,共30页
The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the... The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the high cost and long duration of operational tests,it is essential to plan the test in advance.To solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission reliability.Therefore,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test plans.This study first constructs a mission reliability model for the UAV swarm in the combat stage.Then,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability model.Finally,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the model.The optimal plans considering both reliability and cost are obtained.The proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning. 展开更多
关键词 UAV swarm PMS MOQPSO BDD mission reliability operational test planning
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Step-stress accelerated degradation test planning based on Wiener processwith correlation 被引量:1
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作者 Lei He Rong-Xian Yue Daojiang He 《Statistical Theory and Related Fields》 2018年第1期58-67,共10页
To assess the lifetime distribution of highly reliable or expensive product,one of the most commonly used strategies is to construct step-stress accelerated degradation test(SSADT)which can curtail the test duration a... To assess the lifetime distribution of highly reliable or expensive product,one of the most commonly used strategies is to construct step-stress accelerated degradation test(SSADT)which can curtail the test duration and reduce the test cost.In reality,it is not unusual for a unit with a higher degradation rate which exhibits a more volatile degradation path.Recently,Ye,Chen,and Shen[(2015).A new class of Wiener process models for degradation analysis.Reliability Engineering and System Safety,139,58–67]proposed a Wiener process to capture the positive correlation between the drift rate and the volatility.In this paper,an optimal SSADT plan is developed under the assumption that the underlying degradation path follows the Wiener process with correlation.Firstly,the stochastic diffusion process is introduced to model a typical SSADT problem.Then the design variables,including the sample size,the measurement frequency and the numbers of measurements under each stress level,are optimised by minimising the asymptotic variance of the estimated p-percentile of the product’s lifetime distribution subject to the total experimental cost not exceeding a pre-specified budget.Finally,a numerical example is presented to illustrate the proposed method. 展开更多
关键词 Step-stress accelerated degradation test Wiener process CORRELATION optimal test plan
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IEC releases a standard on environmental testing
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《China Standardization》 2025年第6期13-13,共1页
In recent years,the application scenarios of electrical and electronic products have become increasingly diverse worldwide.The impact of climatic environmental tests on the performance of related products has attracte... In recent years,the application scenarios of electrical and electronic products have become increasingly diverse worldwide.The impact of climatic environmental tests on the performance of related products has attracted much attention,and formulating scientific and reasonable environmental test plans has become an important step to ensure product quality and reliability. 展开更多
关键词 climatic environmental tests product quality electrical electronic products product quality reliability formulating scientific reasonable environmental test plans RELIABILITY environmental testing
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Efficient Penetration Testing Path Planning Based on Reinforcement Learning with Episodic Memory
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作者 Ziqiao Zhou Tianyang Zhou +1 位作者 Jinghao Xu Junhu Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2613-2634,共22页
Intelligent penetration testing is of great significance for the improvement of the security of information systems,and the critical issue is the planning of penetration test paths.In view of the difficulty for attack... Intelligent penetration testing is of great significance for the improvement of the security of information systems,and the critical issue is the planning of penetration test paths.In view of the difficulty for attackers to obtain complete network information in realistic network scenarios,Reinforcement Learning(RL)is a promising solution to discover the optimal penetration path under incomplete information about the target network.Existing RL-based methods are challenged by the sizeable discrete action space,which leads to difficulties in the convergence.Moreover,most methods still rely on experts’knowledge.To address these issues,this paper proposes a penetration path planning method based on reinforcement learning with episodic memory.First,the penetration testing problem is formally described in terms of reinforcement learning.To speed up the training process without specific prior knowledge,the proposed algorithm introduces episodic memory to store experienced advantageous strategies for the first time.Furthermore,the method offers an exploration strategy based on episodic memory to guide the agents in learning.The design makes full use of historical experience to achieve the purpose of reducing blind exploration and improving planning efficiency.Ultimately,comparison experiments are carried out with the existing RL-based methods.The results reveal that the proposed method has better convergence performance.The running time is reduced by more than 20%. 展开更多
关键词 Intelligent penetration testing penetration testing path planning reinforcement learning episodic memory exploration strategy
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Novel Accelerating Life Test Method and Its Application by Combining Constan Stress and Progressive Stress 被引量:2
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作者 Wen-Hua Chen Fan Yang +2 位作者 Ping Qian Jun Pan Qing-Chuan He 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第5期17-24,共8页
Constant stress accelerated life tests(ALTs) can be applied to obtain a high estimation accuracy of reliability measure?ments, but these are time?consuming tests. Progressive stress ALTs can yield failures more quickl... Constant stress accelerated life tests(ALTs) can be applied to obtain a high estimation accuracy of reliability measure?ments, but these are time?consuming tests. Progressive stress ALTs can yield failures more quickly but cannot guaran tee the estimation accuracy of reliability measurements. In this paper, a progressive?constant combination stress ALT is proposed to combine the merits of both tests. The optimal plan, in which the design variables are the initial pro?gressive stress level, the progressive stress ramp rate, the sample allocation proportion of the progressive stress and the constant stress level, is determined using the principle of minimizing the asymptotic variance of the maximum likelihood estimator of the natural log reliable life for the connectors. A comparison between the optimal PCCSALT plan and the CSALT plan with the same sample size and estimation accuracy shows that the test time is reduced by 13.59% by applying the PCCSALT. 展开更多
关键词 Constant stress Progressive stress Accelerated life test Optimal test plan Reliability test
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Inference and optimal design on step-stress partially accelerated life test for hybrid system with masked data 被引量:1
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作者 SHI Xiaolin LU Pu SHI Yimin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期1089-1100,共12页
Under Type-Ⅱ progressively hybrid censoring, this paper discusses statistical inference and optimal design on stepstress partially accelerated life test for hybrid system in presence of masked data. It is assumed tha... Under Type-Ⅱ progressively hybrid censoring, this paper discusses statistical inference and optimal design on stepstress partially accelerated life test for hybrid system in presence of masked data. It is assumed that the lifetime of the component in hybrid systems follows independent and identical modified Weibull distributions. The maximum likelihood estimations(MLEs)of the unknown parameters, acceleration factor and reliability indexes are derived by using the Newton-Raphson algorithm. The asymptotic variance-covariance matrix and the approximate confidence intervals are obtained based on normal approximation to the asymptotic distribution of MLEs of model parameters. Moreover,two bootstrap confidence intervals are constructed by using the parametric bootstrap method. The optimal time of changing stress levels is determined under D-optimality and A-optimality criteria.Finally, the Monte Carlo simulation study is carried out to illustrate the proposed procedures. 展开更多
关键词 hybrid system step-stress partially accelerated life test Type-Ⅱ progressively hybrid censored and masked data statistical inference optimal test plan
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多策略融合改进的天鹰算法机器人路径规划
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作者 程小虎 章翔峰 姜宏 《电子测量技术》 北大核心 2026年第3期1-10,共10页
针对传统天鹰算法(AO)在高维复杂优化问题和机器人路径规划应用中易陷入局部最优、收敛速度慢的缺陷,本文提出了一种基于空中搜索和三角变异算子改进的天鹰算法。首先,通过Halton低差异序列提高初始种群分布的均匀性;其次,在算法收缩开... 针对传统天鹰算法(AO)在高维复杂优化问题和机器人路径规划应用中易陷入局部最优、收敛速度慢的缺陷,本文提出了一种基于空中搜索和三角变异算子改进的天鹰算法。首先,通过Halton低差异序列提高初始种群分布的均匀性;其次,在算法收缩开发阶段融合北极海鹦算法的空中搜索机制提升种群的协同进化能力与搜索精度;最后,利用三角变异算子改善算法后期的收敛性能。随后在CEC2017测试函数上与五种同类算法进行对比,并采用秩和检验评估其差异性。最后,将所提出的算法应用于机器人路径规划应用。实验结果表明,HATAO算法具有较强的搜索精度和较快的收敛速度,不仅能有效避开障碍物、获得较短路径,还具有更好的稳定性,在简单和复杂场景下路径相比于原天鹰算法分别缩短了约4.96%、6.34%,验证了算法在实际路径规划任务中的有效性与鲁棒性。 展开更多
关键词 元启发式算法 天鹰算法 CEC2017测试函数 机器人路径规划
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多策略融合二次插值优化算法的机器人多任务点路径规划
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作者 田怡凡 杨光永 徐天奇 《组合机床与自动化加工技术》 北大核心 2026年第3期75-81,共7页
针对二次插值优化算法收敛速度慢和容易陷入局部最优等问题,提出一种多策略融合二次插值优化算法。首先,将非线性复合无限折叠迭代混沌映射用于种群初始化,增强算法的全局搜索能力和多样性;其次,提出一种基于种群动态比例信息共享机制... 针对二次插值优化算法收敛速度慢和容易陷入局部最优等问题,提出一种多策略融合二次插值优化算法。首先,将非线性复合无限折叠迭代混沌映射用于种群初始化,增强算法的全局搜索能力和多样性;其次,提出一种基于种群动态比例信息共享机制的改进策略,增强种群的多样性和全局搜索能力,提高算法收敛精度;最后,加入了一种基于种群交互机制的动态重启机制优化策略,避免搜索过程陷入局部最优解或停滞。将改进算法与传统QIO算法以及4个先进算法在CEC2017测试集上进行对比实验,结果相比所选对比算法(QIO、SMA、SWO、EDO、SCSO)显示出明显优势。将改进算法与A*算法融合用于机器人多任务点路径规划,结果表明改进算法在实验设置的条件下使搜索效率更高、收敛速度更快和路径规划更合理。 展开更多
关键词 二次插值优化算法 无限折叠迭代混沌映射 动态重启机制 CEC2017测试集 路径规划
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LNG燃料动力船气试流程及实施要点
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作者 程辉 程林 +1 位作者 张凯 王涛 《舰船科学技术》 北大核心 2026年第2期79-83,共5页
随着航运业绿色低碳转型不断深入,液化天然气(LNG)成为当前主流船用清洁能源之一,LNG燃料动力船迎来规模化发展阶段。气试作为LNG燃料动力船从建造到交付过程中至关重要的一环,是对船舶建造质量和LNG燃料动力系统的重要检验程序,因此需... 随着航运业绿色低碳转型不断深入,液化天然气(LNG)成为当前主流船用清洁能源之一,LNG燃料动力船迎来规模化发展阶段。气试作为LNG燃料动力船从建造到交付过程中至关重要的一环,是对船舶建造质量和LNG燃料动力系统的重要检验程序,因此需进一步规范流程。本文以7 500 CEU汽车滚装船气试为例,阐述了LNG燃料动力船的气试流程、实施要点,并提出控制要点优化方案及应急处置措施,为船舶气试方案编制与安全作业提供借鉴。 展开更多
关键词 LNG燃料动力船 气试 实施要点 应急处置方案
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一种基于多智能体架构的自动化渗透测试系统
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作者 董英娟 吕萍 刘兵 《信息网络安全》 北大核心 2026年第4期654-664,共11页
近年来,网络攻击呈现高度组织化和自动化趋势。在以大语言模型为主的人工智能技术加持下,攻击者能够快速编写和派生恶意代码,并基于僵尸网络构建针对特定目标的自动化和分布式的侦查与攻击流程,给网络安全防护带来了威胁和挑战。为有效... 近年来,网络攻击呈现高度组织化和自动化趋势。在以大语言模型为主的人工智能技术加持下,攻击者能够快速编写和派生恶意代码,并基于僵尸网络构建针对特定目标的自动化和分布式的侦查与攻击流程,给网络安全防护带来了威胁和挑战。为有效应对以上挑战,文章提出并设计一种基于多智能体架构的自动化渗透测试系统,将传统渗透测试任务拆解为具有原子性的子任务,并交由各智能体联合完成。实验结果表明,该系统在多项测试指标上均显著领先于传统漏洞扫描工具,能够全面识别被测信息系统中的多类型安全漏洞,并为漏洞披露提供高度可信的证据链。此外,该系统能够生成可执行的修复建议,实现渗透测试流程的自动化与工程化,为机构开展常态化网络安全漏洞管理工作提供一种先进、高效和稳定的解决方案。 展开更多
关键词 渗透测试系统 多智能体架构 自主任务规划 系统与网络安全
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大学生体质健康测试失范行为影响因素研究——基于技术接受模型的计划行为理论
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作者 张冲 王舜 《体育科技文献通报》 2026年第2期142-148,共7页
大学生体质健康测试在激励和促进学生参加体育锻炼的同时,也出现一系列行为乱象,受到社会的广泛关注。本研究基于技术接受模型,以计划行为理论的态度、主观规范、知觉行为控制为中介变量,构建大学生体质健康测试失范行为影响因素假设模... 大学生体质健康测试在激励和促进学生参加体育锻炼的同时,也出现一系列行为乱象,受到社会的广泛关注。本研究基于技术接受模型,以计划行为理论的态度、主观规范、知觉行为控制为中介变量,构建大学生体质健康测试失范行为影响因素假设模型,运用问卷调查法和结构方程模型(SEM)进行实证分析,并对其作用机制展开深入研究。结果显示:(1)体质健康测试的感知易用性对其感知有用性存在显著正向影响;(2)体质健康测试的感知有用性与感知易用性,对测试态度、测试主观规范、测试知觉行为控制均存在显著正向影响;(3)体质健康测试主观规范对测试态度、测试知觉行为控制存在显著正向影响;测试主观规范、测试知觉行为控制对测试意向存在显著正向影响,并通过测试意向间接影响测试行为;(4)体质健康测试意向对测试行为存在显著正向影响。基于上述研究结果,本研究提出以下对策建议:(1)加强体质健康测试规范宣传教育,规范大学生体质健康测试行为;(2)培养学生常态化体育锻炼习惯,提升学生体质健康综合水平;(3)重塑大学生对体质健康测试的正确认知,营造良好的校园体质健康测试文化氛围。 展开更多
关键词 大学生体测 失范行为 技术接受模型 计划行为理论
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Airtest平台自动化测试方案设计与实现 被引量:4
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作者 张娜 蔡乐俊 +2 位作者 徐曼 包梓群 包晓安 《软件导刊》 2021年第12期88-92,共5页
为改善传统移动端自动化测试方案控件覆盖率低,不同操作系统脚本之间不兼容且复用率低的缺点,提出一种基于蚁群算法的全路径最优规划算法。首先通过深度优先搜索算法对界面控件预处理,然后逐一遍历获取控件信息合并冗余控件,最后结合改... 为改善传统移动端自动化测试方案控件覆盖率低,不同操作系统脚本之间不兼容且复用率低的缺点,提出一种基于蚁群算法的全路径最优规划算法。首先通过深度优先搜索算法对界面控件预处理,然后逐一遍历获取控件信息合并冗余控件,最后结合改进的蚁群算法生成测试用例。基于该算法提出一种自动化测试方案,在Airtest自动化测试平台上进行测试并在移动端平台进行验证。结果表明:该方案前期快速收敛,测试控件,达到85%的覆盖率,比基于录制回放测试方案提高了3倍且兼容多个操作平台,显示该方案在兼容性以及测试可信度上均有优势。 展开更多
关键词 自动化测试方案 蚁群算法 信息素 POCO Airtest
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General Consideration of Measuring System for Operational Test of Thyristor Valves of Ultra High Voltage DC Power Transmission 被引量:1
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作者 ZHOU Hui-gao XU Fan +2 位作者 ZHANG Chang-chun HU Zhi-long LIU Pu 《高压电器》 CAS CSCD 北大核心 2011年第9期1-5,共5页
Thyristor valve is one of the key equipments for ultra high voltage direct current(UHVDC) power transmission projects.Before being installed on site,they need to be tested in a laboratory in order to verify their oper... Thyristor valve is one of the key equipments for ultra high voltage direct current(UHVDC) power transmission projects.Before being installed on site,they need to be tested in a laboratory in order to verify their operational performance to satisfy the technical specification of project related.Test facilities for operational tests of thyristor valves are supposed to enable to undertake more severe electrical stresses than those being applied in the thyristor valves under test(test objects).On the other hand,the stresses applied into the test objects are neither higher nor lower than specified by the specification,because inappropriate stresses applied would result in incorrect evaluation of performance on the test objects,more seriously,would cuase the damage of test objects with expensive cost losing.Generally,the process of operational tests is complicated and performed in a complex synthetic test circuit(hereafter as STC),where there are a lot of sensors used for measuring,monitoring and protection on line to ensure that the test circuit functions in good condition.Therefore,the measuring systems embedded play a core role in STC,acting like "eyes".Based on the first project of building up a STC in China,experience of planning measuring systems is summarized so as to be referenced by related engineers. 展开更多
关键词 UHVDC thyristor valves operational test synthetic test circuit measuring system planning
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转子帆船舶改装工程的质量策划与控制研究
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作者 叶志华 《广东造船》 2026年第1期92-95,共4页
随着全球航运业碳减排任务加剧,新能源改装成为了船舶绿色化改装的发展方向,其中转子帆具备高效的风能助推性能。本文分析了转子帆的工作原理与改装效益,围绕转子帆船舶改装工程的质量策划与控制,分析了材料管控、基座装配、焊接、核验... 随着全球航运业碳减排任务加剧,新能源改装成为了船舶绿色化改装的发展方向,其中转子帆具备高效的风能助推性能。本文分析了转子帆的工作原理与改装效益,围绕转子帆船舶改装工程的质量策划与控制,分析了材料管控、基座装配、焊接、核验、液压管系安装及检测等改装流程中的质量控制风险点,构建了质量控制体系、关键节点质量控制措施和操作指南,为转子帆及同类复杂船舶改装工程提供了理论与技术借鉴,对推动航运业绿色低碳转型具有重要的现实意义。 展开更多
关键词 转子帆 船舶改装 质量策划 焊接质量控制 无损检测 绿色航运
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长水机场下穿隧道悬臂掘进机施工路径规划及围岩损伤特征分析 被引量:1
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作者 薛亚东 张庆雨 +3 位作者 郭永发 丁文云 杨进京 康殿海 《隧道建设(中英文)》 北大核心 2025年第6期1076-1089,共14页
针对大断面机场下穿隧道施工中爆破法扰动围岩的技术难题,以渝昆高铁长水机场隧道为依托,提出基于悬臂掘进机法的低扰动施工路径规划与围岩损伤演化分析方法。基于FLAC3D软件构建三维数值模型,采用分块多步开挖法模拟悬臂掘进机渐进开... 针对大断面机场下穿隧道施工中爆破法扰动围岩的技术难题,以渝昆高铁长水机场隧道为依托,提出基于悬臂掘进机法的低扰动施工路径规划与围岩损伤演化分析方法。基于FLAC3D软件构建三维数值模型,采用分块多步开挖法模拟悬臂掘进机渐进开挖过程,通过渐进释放围岩荷载,精确表征机械开挖的低扰动特性。结合现场松动圈测试与孔内光学摄像,构建数值模拟与工程实测的交叉验证机制,重点分析悬臂掘进机施工路径及Ⅲ—Ⅴ级围岩条件下位移场、应力场及塑性区的时变特性。研究表明:1)分块多步开挖法可有效模拟悬臂掘进机渐进式开挖特性,数值模拟结果与现场测试数据吻合度高,证实了该方法的科学性及适应性。2)相比于常规掘进路径,分块掘进路径可降低Ⅴ级围岩的拱顶沉降21.7%,有效控制围岩变形。3)围岩损伤特征呈现显著等级相关性,Ⅲ、Ⅳ级围岩损伤集中于隧道轮廓附近,塑性区以拉伸破坏为主;而Ⅴ级围岩损伤范围扩大,剪切破坏占比显著增加。 展开更多
关键词 悬臂掘进机 机场下穿隧道 围岩损伤 松动圈测试 数值模拟 路径规划
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