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A STUDY OF FINE DENIER POLYPROPYLENE FIBER KNITTED FABRICS' WET COMFORT——THE WET COMFORT STUDIED BY THE NORMAL OBJECTIVE TEST
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作者 李俊 王云仪 张渭源 《Journal of China Textile University(English Edition)》 EI CAS 1996年第2期1-10,共10页
Based on the theory of moisture vapor permeability and liquid moisture transmission through fabric, this paper is mainly concerned with the wet comfort of the fine denier polypropylene fiber knitted fabrics. The liqui... Based on the theory of moisture vapor permeability and liquid moisture transmission through fabric, this paper is mainly concerned with the wet comfort of the fine denier polypropylene fiber knitted fabrics. The liquid water transport property the liquid water retention property, the moisture permeability property, the moisture releasing and drying property of these fabrics are tested by normal objective ways and discussed. At last, according to these properties these fabries are classified by grey model synthetic evaluation method. 展开更多
关键词 polypropylene tiber KNITTED FABRICS moisture transmission COMFORT objective test
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Multiple Objective Test Design for Accelerated Destructive Degradation Tests
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作者 黄硕 杨军 +1 位作者 彭锐 赵宇 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期954-956,共3页
Accelerated destructive degradation tests(ADDTs)are powerful to provide reliability information in the degradation processes with destructive measurements.In order to carry out an ADDT efficiently,both the estimation ... Accelerated destructive degradation tests(ADDTs)are powerful to provide reliability information in the degradation processes with destructive measurements.In order to carry out an ADDT efficiently,both the estimation precision of parameters and the test cost should be considered.On the basis of the given degradation model and failure criterion,a multiple-objective optimization model for the design of ADDTs is proposed.Under constrains of the maximum measurement time,the total sample size and the number of stress levels,a comprehensive target function is suggested to reflect both the precision of lifetime estimation and total cost,and the optimal test plan is obtained,which is composed by optimal choices for samples size,measurement frequency,and the number of measurements at each stress level.A real example is illustrated to demonstrate the implementation of the proposed approach. 展开更多
关键词 accelerated destructive degradation tests(ADDTs) highly reliable products multiple objectives test cost asymptotic variance
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Subjective V.S Objective Test Item
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作者 陶永艳 《海外英语》 2011年第4X期129-129,共1页
In this article,I will talk about the definition and discrimination of subjective test and objective test.The strong points and weak points are also discussed.Although each has its own disadvantages,subjective test an... In this article,I will talk about the definition and discrimination of subjective test and objective test.The strong points and weak points are also discussed.Although each has its own disadvantages,subjective test and objective test will still play important roles at present or in future.A good classroom test will usually contain both subjective and objective test items. 展开更多
关键词 SUBJECTIVE and objective test LANGUAGE
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Test anxiety in objective structured clinical examinations (OSCEs) compared with traditional assessment methods in undergraduate midwifery students
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作者 Mahbobeh Faramarzi Hajar Pasha +4 位作者 Afsaneh Bakhtiari Hajar Salmalian Mouloud Agajani Delavar Fatemeh Nasiri Amiri Maryam Nikpour 《Health》 2013年第12期2204-2209,共6页
BACKGROUND: Final comprehensive exam is the most important examination for midwifery students to evaluate their professional ability and Test anxiety is a common phenomenon among college students. Because test anxiety... BACKGROUND: Final comprehensive exam is the most important examination for midwifery students to evaluate their professional ability and Test anxiety is a common phenomenon among college students. Because test anxiety is one of the problems of educational systems, this study was performed to compare test anxiety in objective structured clinical examinations (OS-CEs) and traditional assessment methods (TAM) among Undergraduate Midwifery Students. Methods: In this descriptive-analytical study, 52 students of Babol Midwifery College were participated in the study. 20 students were evaluated using TAM in November 2010, and 32 students were evaluated using the OSCE method in July 2011. Data were collected via a two-component questionnaire including demographic data and the test anxiety inventory (TAI). Results: All of midwifery students were women;the mean age of students, ages of father and mother’s were 23.1 ± 0.7, 52.3 ± 3.5 and 47.8 ± 4.9 years, respectively. Most of the students were single (61.5%). The mean education levels of father and mother’s were 11.6 ± 4.5 and 9.9 ± 4.0 years, respectively. The mean score of test anxiety in students was 42.51 ± 13.16. The most of participants did have moderate test anxiety (56.9%), two present not had any test anxiety, 37.3% had low test anxiety, and 3.9% had severe test anxiety. In sum, 98% had some degrees of test anxiety. There were the statistical differences in the mean score of text anxiety in OSCEs Compared with TAM in Undergraduate Midwifery Students (39.38 ± 13.81 vs. 47.35 ± 10.67, P = 0.033). Also, the mean severity of anxiety was different in two groups. The mean of moderate/severe test anxiety was more in TAM compared with OSCEs (52.57% vs. 49.56%, p = 0.000). The test anxiety had a positive correlation with father’s education, mother’s education (0.286, p = 0.042), father’s age, mother’s age, marital status, residency (0.292, p = 0.042). Also, there are negative correlations with student age, satisfaction, total Grade Point Average (GPA) (-0.387, p = 0.007), final score, type of assessment (-0.298, p = 0.033). There is a significant difference between the severity anxiety residency in total (p = 0.10) and OSCEs (p = 0.049) groups, mother’s education in total (p = 0.005) and OSCEs groups (0.012) and GPA (p = 0.028). Conclusion: OSCEs were superior to TAM in the reduction of test anxiety in midwifery students. The prevalence of test anxiety was in TAM than OSCEs method;therefore, using OSCEs is acknowledged as an effective assessment tool and is seen as the gold standard for evaluating clinical performance. 展开更多
关键词 objective STRUCTURED Clinical EXAMINATION test ANXIETY MIDWIFERY STUDENT
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Optimal Test Points Selection Based on Multi-Objective Genetic Algorithm
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作者 Yong Zhang Xi-Xiang Chen Guan-Jun Liu Jing Qiu Shu-Ming Yang 《Journal of Electronic Science and Technology of China》 2009年第4期317-321,共5页
A new approach to select anoptimal set of test points is proposed. The described method uses fault-wise table and multi-objective genetic algorithm to find the optimal set of test points. First, the fault-wise table i... A new approach to select anoptimal set of test points is proposed. The described method uses fault-wise table and multi-objective genetic algorithm to find the optimal set of test points. First, the fault-wise table is constructed whose entries are measurements associated with faults and test points. The selection of optimal test points is transformed to the selection of the columns that isolate the rows of the table. Then, four objectives are described according to practical test requirements. The multi-objective genetic algorithm is explained. Finally, the presented approach is illustrated by a practical example. The results indicate that the proposed method can efficiently and accurately find the optimal set of test points and is practical for large scale systems. 展开更多
关键词 Design for testability multi-objective genetic algorithm system testing test points selection.
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Object-Z规格说明测试用例的自动生成器 被引量:5
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作者 许庆国 缪淮扣 +1 位作者 曹晓夏 胡晓波 《软件学报》 EI CSCD 北大核心 2011年第6期1155-1168,共14页
对Object-Z形式规格说明构造测试用例的研究,目前主要集中在理论研究阶段,测试用例的自动生成几乎没有相应的工具支持.Object-Z是基于数学和逻辑的语言,并大量使用了模式复合和简写形式,这给计算机提取完整语义用以自动产生测试用例造... 对Object-Z形式规格说明构造测试用例的研究,目前主要集中在理论研究阶段,测试用例的自动生成几乎没有相应的工具支持.Object-Z是基于数学和逻辑的语言,并大量使用了模式复合和简写形式,这给计算机提取完整语义用以自动产生测试用例造成了困难.通过展开Object-Z规格说明中的模式定义,改进Object-Z的文法结构,给出了提取Object-Z规格说明语义的方法,研究了从Object-Z规格说明产生测试用例的自动化过程.这一过程主要包含3个阶段:Object-Z语言的自动解析、语义自动抽取和测试用例自动产生.通过介绍的工具原型,可以很容易得到规格说明中的各种语义;基于某些测试准则,能够方便自动产生可视化的抽象测试用例. 展开更多
关键词 基于规格说明的测试 object-Z 语义提取 测试用例生成器
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Quantifying Reusability of Object Oriented Design: A Testability Perspective
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作者 Mahfuzul Huda Yagya Dutt Sharma Arya Mahmoodul Hasan Khan 《Journal of Software Engineering and Applications》 2015年第4期175-183,共9页
The quality factor of class diagram is critical because it has a significant influence on overall quality of the product, delivered finally. Testability analysis, when done early in the software creation process, is a... The quality factor of class diagram is critical because it has a significant influence on overall quality of the product, delivered finally. Testability analysis, when done early in the software creation process, is a criterion of critical importance to software quality. Reusability is an important quality factor to testability. Its early measurement in object oriented software especially at design phase, allows a design to be reapplied to a new problem without much extra effort. This research paper proposes a research framework for quantification process and does an extensive review on reusability of object oriented software. A metrics based model “Reusability Quantification of Object Oriented Design” has been proposed by establishing the relationship among design properties and reusability and justifying the correlation with the help of statistical measures. Also, “Reusability Quantification Model” is empirically validated and contextual significance of the study shows the high correlation for model acceptance. This research paper facilitates to software developers and designer, the inclusion of reusability quantification model to access and quantify software reusability for quality product. 展开更多
关键词 REUSABILITY testABILITY object ORIENTED DESIGN DESIGN Metrics object ORIENTED SOFTWARE SOFTWARE Quality Model SOFTWARE testing Effort
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Class Tester:一个基于状态转换的类测试工具的设计与实现 被引量:1
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作者 谢晓东 卢炎生 《小型微型计算机系统》 CSCD 北大核心 2007年第3期447-450,共4页
面向对象软件测试的类测试方法有三种:基于规约说明的类测试方法、基于类流图的类测试方法、基于状态转换的类测试方法.本文描述了一个针对C++语言的基于状态的类测试工具的设计和实现,介绍了该工具的体系结构和主要算法.对测试驱动器... 面向对象软件测试的类测试方法有三种:基于规约说明的类测试方法、基于类流图的类测试方法、基于状态转换的类测试方法.本文描述了一个针对C++语言的基于状态的类测试工具的设计和实现,介绍了该工具的体系结构和主要算法.对测试驱动器的自动生成的方法作了详细介绍.最后通过一个实例描述了该工具的工作流程. 展开更多
关键词 软件测试 面向对象软件测试 类测试 测试工具
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一种基于Object-Z规格说明的集成测试用例生成方法 被引量:2
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作者 朱义毅 缪淮扣 唐新香 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第1期60-65,共6页
形式化方法具有精确的描述性和很强的抽象性.用形式化方法描述规格说明,避免了在需求分析阶段对数据结构和算法细节的详细描述,同时又避免了一般建模方法中的模糊性和歧义性.针对组件系统的集成测试产生测试用例,提出一种使用Object-Z... 形式化方法具有精确的描述性和很强的抽象性.用形式化方法描述规格说明,避免了在需求分析阶段对数据结构和算法细节的详细描述,同时又避免了一般建模方法中的模糊性和歧义性.针对组件系统的集成测试产生测试用例,提出一种使用Object-Z模式描述组件模型的方法,并且针对模型提出测试准则,产生测试场景,然后根据得到的测试场景产生测试用例. 展开更多
关键词 规格说明 集成测试 object—Z模型 测试用例 组件
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基于Object-Z与Markov链的校园卡系统测试用例
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作者 仲晓敏 侯建花 杨长青 《微电子学与计算机》 CSCD 北大核心 2012年第3期73-77,共5页
针对提高校园卡系统准确性和可靠性测试的要求,提出了Object-Z与Markov链结合的测试用例自动生成算法.使用Object-Z对系统进行形式化规约,生成测试场景和操作顺序图;将操作顺序图转换为Markov链使用模型;根据测试场景和Markov链使用模... 针对提高校园卡系统准确性和可靠性测试的要求,提出了Object-Z与Markov链结合的测试用例自动生成算法.使用Object-Z对系统进行形式化规约,生成测试场景和操作顺序图;将操作顺序图转换为Markov链使用模型;根据测试场景和Markov链使用模型生成数量相对合理的测试用例.该方法无需对系统进行运行,在需求分析与测试阶段就能对系统的功能进行测试.生成的校园卡系统测试用例证明该方法是有效的,并且在提高测试覆盖率的同时,使用Markov链也能保证对系统的可靠性测试. 展开更多
关键词 校园卡系统 object-Z 测试场景 MARKOV链 使用模型 测试用例
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Burning characteristics of microcellular combustible objects 被引量:1
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作者 Wei-tao YANG Yu-xiang LI San-jiu YING 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第2期106-110,共5页
Microcellular combustible objects for application of combustible case,caseless ammunition or combustible detonator-holding tubes are fabricated through one-step foaming process,in which supercritical CO_2 is used as f... Microcellular combustible objects for application of combustible case,caseless ammunition or combustible detonator-holding tubes are fabricated through one-step foaming process,in which supercritical CO_2 is used as foaming agent.The formulations consist of inert polymer binder and ultra fine RDX.For the inner porous structures of microcellular combustible objects,the cell sizes present a unimodal or bimodal distribution by adjusting the foaming conditions.Closed bomb test is to investigate the influence of both porous structure style and RDX content on burning behavior.The sample with bimodal distribution of cell sizes burns faster than that with unimodal distribution,and the concentration of RDX can influence the burning characteristics in a positive manner.In addition,the translation of laminar burning to convective burning is determined by burning rate versus pressure curves of samples at two different loading densities,and the resulting transition pressure is 30 MPa.Moreover,the samples with bigger sample size present higher burning rate,resulting in providing deeper convective depth.Dynamic vivacity of samples is also studied.The results show that the vivacity increases with RDX content and varies with inner structure. 展开更多
关键词 燃烧性能 可燃物 超临界二氧化碳 发泡过程 多孔结构 双峰分布 单峰分布 压力曲线
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基于匝道合流数据的自动驾驶汽车安全性测试评价方法 被引量:1
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作者 李文礼 李超 +2 位作者 李中峰 易帆 李安 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期84-91,共8页
针对自动驾驶汽车测试场景不明确、评价模型主观性强等问题,研究了高速匝道汇入场景下的典型测试场景提取方法和自动驾驶汽车匝道汇入安全性客观评价方法。深入分析了匝道汇入功能场景下的逻辑场景要素,对自然驾驶数据中的自车速度、车... 针对自动驾驶汽车测试场景不明确、评价模型主观性强等问题,研究了高速匝道汇入场景下的典型测试场景提取方法和自动驾驶汽车匝道汇入安全性客观评价方法。深入分析了匝道汇入功能场景下的逻辑场景要素,对自然驾驶数据中的自车速度、车间距离、前车车速等逻辑场景要素进行聚类,得到两类典型的匝道汇入测试场景用于自动驾驶汽车的仿真测试。构建多层次自动驾驶汽车评价体系,引入基于自然驾驶数据的核密度估计模型来获取指标最优阈值,建立以最优阈值为参考序列、以层次分析法(AHP)和客观赋权法(CRITIC)为权重输入的灰色关联理评价模型,对自动驾驶汽车在汇入过程中的安全性进行客观评价。评价结果表明:基于核密度估计的灰色关联理论模型评价结果与主观模糊综合分析模型的评价结果相似率达98.01%,验证了客观模型的有效性。 展开更多
关键词 车辆工程 测试评价 客观评价模型 聚类分析 核密度估计
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An approach to formalizing specification-based class testing
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作者 缪淮扣 刘玲 《Journal of Shanghai University(English Edition)》 CAS 2006年第1期25-32,共8页
This paper presents a framework that can be used to formalize the specification-based single-class test generation process. Object-Z is used to describe both software requirements and the proposed framework. Using thi... This paper presents a framework that can be used to formalize the specification-based single-class test generation process. Object-Z is used to describe both software requirements and the proposed framework. Using this framework, test engineers can automatically get the testing process model during the test generation process. With this model, properties of test cases ( such as relationship between test cases and methods can easily be captured. Furthermore, with the framework, the test process model can be updated automatically with the test generation process. The properties of test cases can then be updated correspondingly. It will greatly facilitate the regression testing. The main contribution of this paper is that it provides an approach to formalizing testing process by extending existing framework to class testing, and a way to represent test cases as multi-part, multi-step, multi-level artifacts. 展开更多
关键词 test class framework class testing finite state machine (FSM) object-Z.
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曲线轨道式隔震装置的结构优化与应用研究
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作者 赵守江 柏文 戴君武 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期355-364,共10页
针对浮放物体的防震保护需求,研发出一款基于新型抗侧移组件的曲线轨道式隔震装置。阐述它的构造特点和运行机制,并依据结构原理制作模型,通过试验与理论对比来检验模型的运行质量进而验证方案的可行性。然后结合雨花阁内文物来设计样机... 针对浮放物体的防震保护需求,研发出一款基于新型抗侧移组件的曲线轨道式隔震装置。阐述它的构造特点和运行机制,并依据结构原理制作模型,通过试验与理论对比来检验模型的运行质量进而验证方案的可行性。然后结合雨花阁内文物来设计样机,采用多条楼面波进行样机的振动台试验,测试其隔震效果。最后探讨建筑滤波效应对该类隔震装置设计的影响。研究结果表明:曲线轨道式隔震装置经优化后不仅零部件功能清晰,结构简单易加工,而且具备整体性强、运行质量高以及后期可扩展等优势。试验模型的零部件能充分发挥各自功能,尤其是抗侧移组件极大提高了模型的稳定性和可靠性,理论分析与试验结果吻合良好。结合案例所设计的样机虽具有较好的隔震性能,但限于非线性双自由度的结构特点,重复试验的响应结果存在差异,工程应用中应予以重视。当楼面波不易获取且隔震装置周期远离建筑自振周期时,依据楼面加速度放大系数,将调幅后的原始波作为隔震装置设计依据是可行的且结果偏保守。 展开更多
关键词 曲线轨道式 隔震装置 振动台试验 浮放物体 滤波效应
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基于骨架几何位置调整的座椅抗鞭打性能优化
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作者 马志雄 施金金 +1 位作者 郭韬嵘 刘鹏举 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第10期11-17,共7页
为了减小鞭打试验伤害评估中普遍较高的颈部损伤指标(Neck Injury Criterion,NIC)和上颈部伸张弯矩,基于某汽车座椅的LS-DYNA有限元模型和物理试验结果,首先对其基本结构和后碰撞下的运动响应进行分析,使用多体动力学分析软件(Mathemati... 为了减小鞭打试验伤害评估中普遍较高的颈部损伤指标(Neck Injury Criterion,NIC)和上颈部伸张弯矩,基于某汽车座椅的LS-DYNA有限元模型和物理试验结果,首先对其基本结构和后碰撞下的运动响应进行分析,使用多体动力学分析软件(Mathematical Dynamic Model,MADYMO)建立座椅鞭打试验的多体动力学模型.然后,通过伤害机理分析和对座椅主要设计参数的灵敏度分析,确定座椅结构中的主要几何结构参数,并据此建立数值模型.最后,利用多目标优化算法,获得相应的座椅抗鞭打性能优化方案.结果表明,通过调整座椅骨架横梁及头枕位置,提高乘员头部和下颈部运动一致性,使NIC降低58.5%,上颈部伸张弯矩满足最高性能限值. 展开更多
关键词 汽车安全 座椅 鞭打试验 MADYMO 多目标优化
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隔震装置阻尼机构的参数设计与振动台试验 被引量:1
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作者 赵守江 《振动工程学报》 EI CSCD 北大核心 2024年第1期148-155,共8页
为了改善浮放物体隔震装置中阻尼力的施加方式,研制出一款阻尼机构。对其构造和工作机理进行阐述,推导出了它的力学特征表达式,并验证了分析模型的准确性。结合某文物隔震装置的目标性能,利用数值方法对阻尼机构的参数进行设计,并对比... 为了改善浮放物体隔震装置中阻尼力的施加方式,研制出一款阻尼机构。对其构造和工作机理进行阐述,推导出了它的力学特征表达式,并验证了分析模型的准确性。结合某文物隔震装置的目标性能,利用数值方法对阻尼机构的参数进行设计,并对比振动台试验。结果表明:该阻尼机构结构简单,性能稳定;经阻尼参数优化后的隔震装置在满足位移限值的情况下达到了设定的隔震目标;试验与数值分析结果相吻合,证明了阻尼机构参数设计的正确性,同时也检验了隔震装置的安装和运行质量。其中,试验与数值分析结果的吻合程度,尤其是位移时程曲线的吻合程度,可为浮放物体隔震装置的方案对比和质量评估提供思路。 展开更多
关键词 隔震装置 阻尼机构 数值分析 振动台试验 丝杠 浮放物体
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基于熵值法的铝合金缸体低压铸造工艺多目标优化
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作者 邓伟 宋仲模 +3 位作者 雷基林 罗坤 徐远志 张勇 《铸造》 CAS 2024年第6期753-761,共9页
基于有限元软件ProCAST构建某型铝合金缸体的有限元模型,设计L16(44)正交试验方案,探究了浇注温度、模具预热温度、充型时间、保压压力四个工艺参数对凝固时间和缩松体积的影响。采用熵值法分别计算两个评价指标的权重,将凝固时间与缩... 基于有限元软件ProCAST构建某型铝合金缸体的有限元模型,设计L16(44)正交试验方案,探究了浇注温度、模具预热温度、充型时间、保压压力四个工艺参数对凝固时间和缩松体积的影响。采用熵值法分别计算两个评价指标的权重,将凝固时间与缩松体积转化为综合评分值进行单目标优化。通过极差分析与方差分析,得到了各参数对综合评分的影响程度为:浇注温度(A)>模具预热温度(B)>保压压力(D)>充型时间(C),确定了最优的工艺参数为A1B2C1D3。对比原工艺参数方案和优选工艺参数方案发现:凝固时间缩短了20.35%,缩松体积下降了2.96%。经生产试验,缸体铸件外观质量良好,无明显铸造缺陷,验证了最佳工艺参数的合理性。 展开更多
关键词 铝合金缸体 低压铸造 正交试验 熵值法 多目标优化
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基于数据流的K-S变化检测的动态多目标规划算法 被引量:1
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作者 张涛 周晨 +2 位作者 杜锋 陈芳 刘瑞林 《长江大学学报(自然科学版)》 2024年第1期109-116,共8页
为了更加准确地判断环境是否发生变化并快速追踪动态多目标规划问题(dynamicmulti-objectiveoptimization problem,DMOP)当前时刻的Pareto前沿,提出了一种基于数据流的Kolmogorov-Smirnov(K-S)变化检测的动态多目标规划(DSK-SDMOP)算法... 为了更加准确地判断环境是否发生变化并快速追踪动态多目标规划问题(dynamicmulti-objectiveoptimization problem,DMOP)当前时刻的Pareto前沿,提出了一种基于数据流的Kolmogorov-Smirnov(K-S)变化检测的动态多目标规划(DSK-SDMOP)算法。该算法以NSGA-Ⅱ为基础,通过数据流建立2个时刻的检验窗口,再利用K-S检验基于数据流的Pareto最优前沿是否发生变化,检测2个窗口的数据是否服从同一分布来判断环境是否发生变化,并就环境变化的剧烈程度实行相应的应答机制,以提高对环境的适应程度。利用基于数据流的K-S检测方法,对环境变化不会过于敏感,而且不用提前假设对应目标值的分布,易于操作。通过5个动态多目标规划标准测试函数对该算法进行测试,并和现有的2种算法进行对比分析,结果表明该算法处理动态多目标规划问题具有良好的性能。 展开更多
关键词 动态多目标规划 数据流 K-S检验 NSGA-Ⅱ
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复杂内孔结构磨粒流加工的检测评价与优化
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作者 龚灯 赵伦武 +1 位作者 倪帅 韩刚 《电子测量与仪器学报》 CSCD 北大核心 2024年第3期187-194,共8页
为提高军工零件的内孔加工的可靠性和加工质量,通过正交试验法,分析磨粒流加工中,磨料粒度、磨料质量分数、磨粒流工作压力和循环加工次数对阶梯内孔倒圆角半径、材料去除率、内孔表面粗糙度的影响规律,磨粒流工作压力是内孔倒圆角半径... 为提高军工零件的内孔加工的可靠性和加工质量,通过正交试验法,分析磨粒流加工中,磨料粒度、磨料质量分数、磨粒流工作压力和循环加工次数对阶梯内孔倒圆角半径、材料去除率、内孔表面粗糙度的影响规律,磨粒流工作压力是内孔倒圆角半径的首要影响因素,较为显著,材料去除率的首要影响因素是磨料质量分数,而内孔表面粗糙度的首要影响因素是循环加工次数,通过非线性回归分析建立了复杂内孔磨粒流加工效果评价的模型。以改进的带精英策略的快速非支配排序遗传算法(NSGA-II)进行多目标工艺参数寻优,得到了综合平衡权重下的最佳工艺方案(磨料粒度1 000#,磨料质量分数为50%,工作压力为7.5 MPa,循环加工次数为30次),验证试验表明优化结果和实际加工效果具有较好的一致性。 展开更多
关键词 磨粒流 去毛刺工艺 正交试验 加工质量 多目标优化
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Dynamic Slicing of Object Oriented Programs
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作者 Jian\|jun Zhao Department of Computer Science and Engineering, Fukuoka Institute of Technology, Fukuoka 811 0295, Japan 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期391-397,共7页
Program slice has many applications such as program debugging, testing, maintenance, and complexity measurement. A static slice consists of all statements in program P that may effect the value of variable v a... Program slice has many applications such as program debugging, testing, maintenance, and complexity measurement. A static slice consists of all statements in program P that may effect the value of variable v at some point p , and a dynamic slice consists only of statements that influence the value of variable occurrence for specific program inputs. In this paper, we concern the problem of dynamic slicing of object oriented programs which, to our knowledge, has not been addressed in the literatures. To solve this problem, we present the dynamic object oriented dependence graph (DODG)which is an arc classified digraph to explicitly represent various dynamic dependence between statement instances for a particular execution of an object oriented program. Based on the DODG, we present a two phase backward algorithm for computing a dynamic slice of an object oriented program. 展开更多
关键词 program slicing dynamic dependence graph object oriented program SOFTWARE maintenance DEBUGGING testing
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