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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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Personalized Learning Path Recommendations for Software Testing Courses Based on Knowledge Graphs
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作者 Wei Zheng Ruonan Gu +2 位作者 Xiaoxue Wu Lipeng Gao Han Li 《计算机教育》 2023年第12期63-70,共8页
Software testing courses are characterized by strong practicality,comprehensiveness,and diversity.Due to the differences among students and the needs to design personalized solutions for their specific requirements,th... Software testing courses are characterized by strong practicality,comprehensiveness,and diversity.Due to the differences among students and the needs to design personalized solutions for their specific requirements,the design of the existing software testing courses fails to meet the demands for personalized learning.Knowledge graphs,with their rich semantics and good visualization effects,have a wide range of applications in the field of education.In response to the current problem of software testing courses which fails to meet the needs for personalized learning,this paper offers a learning path recommendation based on knowledge graphs to provide personalized learning paths for students. 展开更多
关键词 Knowledge graphs Software testing Learning path Personalized education
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Research on Evacuation Path Planning Based on Improved Sparrow Search Algorithm
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作者 Xiaoge Wei Yuming Zhang +2 位作者 Huaitao Song Hengjie Qin Guanjun Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1295-1316,共22页
Reducing casualties and property losses through effective evacuation route planning has been a key focus for researchers in recent years.As part of this effort,an enhanced sparrow search algorithm(MSSA)was proposed.Fi... Reducing casualties and property losses through effective evacuation route planning has been a key focus for researchers in recent years.As part of this effort,an enhanced sparrow search algorithm(MSSA)was proposed.Firstly,the Golden Sine algorithm and a nonlinear weight factor optimization strategy were added in the discoverer position update stage of the SSA algorithm.Secondly,the Cauchy-Gaussian perturbation was applied to the optimal position of the SSA algorithm to improve its ability to jump out of local optima.Finally,the local search mechanism based on the mountain climbing method was incorporated into the local search stage of the SSA algorithm,improving its local search ability.To evaluate the effectiveness of the proposed algorithm,the Whale Algorithm,Gray Wolf Algorithm,Improved Gray Wolf Algorithm,Sparrow Search Algorithm,and MSSA Algorithm were employed to solve various test functions.The accuracy and convergence speed of each algorithm were then compared and analyzed.The results indicate that the MSSA algorithm has superior solving ability and stability compared to other algorithms.To further validate the enhanced algorithm’s capabilities for path planning,evacuation experiments were conducted using different maps featuring various obstacle types.Additionally,a multi-exit evacuation scenario was constructed according to the actual building environment of a teaching building.Both the sparrow search algorithm and MSSA algorithm were employed in the simulation experiment for multiexit evacuation path planning.The findings demonstrate that the MSSA algorithm outperforms the comparison algorithm,showcasing its greater advantages and higher application potential. 展开更多
关键词 Sparrow search algorithm optimization and improvement function test set evacuation path planning
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Evolution of mechanical parameters of Shuangjiangkou granite under different loading cycles and stress paths
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作者 Liangjie Gu Xia-Ting Feng +2 位作者 Rui Kong Chengxiang Yang Yuelin Xia 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1113-1126,共14页
Surrounding rocks at different locations are generally subjected to different stress paths during the process of deep hard rock excavation.In this study,to reveal the mechanical parameters of deep surrounding rock und... Surrounding rocks at different locations are generally subjected to different stress paths during the process of deep hard rock excavation.In this study,to reveal the mechanical parameters of deep surrounding rock under different stress paths,a new cyclic loading and unloading test method for controlled true triaxial loading and unloading and principal stress direction interchange was proposed,and the evolution of mechanical parameters of Shuangjiangkou granite under different stress paths was studied,including the deformation modulus,elastic deformation increment ratios,fracture degree,cohesion and internal friction angle.Additionally,stress path coefficient was defined to characterize different stress paths,and the functional relationships among the stress path coefficient,rock fracture degree difference coefficient,cohesion and internal friction angle were obtained.The results show that during the true triaxial cyclic loading and unloading process,the deformation modulus and cohesion gradually decrease,while the internal friction angle gradually increases with increasing equivalent crack strain.The stress path coefficient is exponentially related to the rock fracture degree difference coefficient.As the stress path coefficient increases,the degrees of cohesion weakening and internal friction angle strengthening decrease linearly.During cyclic loading and unloading under true triaxial principal stress direction interchange,the direction of crack development changes,and the deformation modulus increases,while the cohesion and internal friction angle decrease slightly,indicating that the principal stress direction interchange has a strengthening effect on the surrounding rocks.Finally,the influences of the principal stress interchange direction on the stabilities of deep engineering excavation projects are discussed. 展开更多
关键词 Triaxial cyclic loading and unloading test Stress path Deformation modulus and elastic deformation increment ratios Fracture degree Cohesion and internal friction angle
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The Coordinated Influence of Indian Ocean Sea Surface Temperature and Arctic Sea Ice on Anomalous Northeast China Cold Vortex Activities with Different Paths during Late Summer 被引量:2
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作者 Yitong LIN Yihe FANG +3 位作者 Chunyu ZHAO Zhiqiang GONG Siqi YANG Yiqiu YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期62-77,共16页
The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NC... The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NCCV intensity with atmospheric circulations in late summer,the sea surface temperature(SST),and Arctic sea ice concentration(SIC)in the preceding months,are analyzed.The sensitivity tests by the Community Atmosphere Model version 5.3(CAM5.3)are used to verify the statistical results.The results show that the coordination pattern of East Asia-Pacific(EAP)and Lake Baikal high pressure forced by SST anomalies in the North Indian Ocean dipole mode(NIOD)during the preceding April and SIC anomalies in the Nansen Basin during the preceding June results in an intensity anomaly for the first type of NCCV.While the pattern of high pressure over the Urals and Okhotsk Sea and low pressure over Lake Baikal during late summer-which is forced by SST anomalies in the South Indian Ocean dipole mode(SIOD)in the preceding June and SIC anomalies in the Barents Sea in the preceding April-causes the intensity anomaly of the second type.The third type is atypical and is not analyzed in detail.Sensitivity tests,jointly forced by the SST and SIC in the preceding period,can well reproduce the observations.In contrast,the results forced separately by the SST and SIC are poor,indicating that the NCCV during late summer is likely influenced by the coordinated effects of both SST and SIC in the preceding months. 展开更多
关键词 machine learning method Northeast China cold vortex path classification Indian Ocean sea surface temperature Arctic sea ice model sensitivity test
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Mechanical behavior of iron ore tailings under standard compression and extension triaxial stress paths 被引量:1
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作者 Alexia Cindy Wagner João Paulo de Sousa Silva +5 位作者 João Vítor de Azambuja Carvalho Ana Luisa Cezar Rissoli Pedro Pazzoto Cacciari Helder Mansur Chaves Hugo Carlos Scheuermann Filho Nilo Cesar Consoli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第7期1883-1894,共12页
The disposal of mining tailings has increasingly focused on the use of dry stacks.These structures offer more security since they use filtered and compacted material.Because of the construction method and the heights ... The disposal of mining tailings has increasingly focused on the use of dry stacks.These structures offer more security since they use filtered and compacted material.Because of the construction method and the heights achieved,the material that compounds the structure can be subjected to different stress paths along the failure plane.The theoretical framework considered in the design of these structures generally is the critical state soil mechanics(CSSM).However,the data in the literature concerning the uniqueness of critical state line(CSL)is still controversial as the soil is subjected to different stress paths.With respect to tailings,this question is even more restricted.This paper studies two tailings with different gradings due to the beneficial processes over extension and compression paths.A series of drained and undrained triaxial tests was conducted over a range of initial densities and stress levels.In the q-p'plane,different critical stress ratio(M)values were obtained for compression and extension stress paths.However,the critical state friction angle is very similar with a slightly higher critical state friction angle for extension tests.Curved stress path dependent CSLs were obtained in the n-lnp0 plane with the extension tests below the CSL defined in compression.Regarding the fines content,the studied tailings presented very similar M and critical state friction angle values.However,the fines content af-fects the volumetric behavior of the studied tailings and the CSLs on the n-lnp0 plane shift downwards with the increasing fines content for compression and extension tests.In relation to dilatancy analysis,the fines content did not present an evident influence on the dilatancy of the materials.However,different values of mean stress ratio N were obtained between compression and extension tests and can corroborate the existence of non-unique CSLs for these materials. 展开更多
关键词 Iron ore tailings(IOTs) Dry stacking Critical state soil mechanics Extension tests Stress path
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A DFT Method for Single-Control Testability of RTL Data Paths for BIST
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作者 Toshimitsu Masuzawa Minoru lzutsu +1 位作者 Hiroki Wada Hideo Fujiwara 《湖南大学学报(自然科学版)》 EI CAS CSCD 2000年第S2期52-60,共9页
This paper presents a new BIST method for RTL data paths based on single-control testability, a new concept of testability. The BIST method adopts hierarchical test. Test pattern generators are placed only on primary ... This paper presents a new BIST method for RTL data paths based on single-control testability, a new concept of testability. The BIST method adopts hierarchical test. Test pattern generators are placed only on primary inputs and test patterns are propagated to and fed into each module. Test responses are similarly propagated to response analyzers placed only on primary outputs. For the propagation of test patterns and test responses paths existing in the data path are utilized. The DFT method for the single-control testability is also proposed. The advantages of the proposed method are high fault coverage (for single Stuck-at faults), low hardware overhead and capability of at-speed test. Moreover, test patterns generated by test pattern generators can be fed into each module at consecutive system clocks, and thus, the BIST can also detect some faults of other fault models (e.g., transition faults and delay faults) that require consecutive application of test patterns at speed of system clock. 展开更多
关键词 built-in self-test design for testability RTL data path hierarchical test
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基于扫视路径速度的隧道入口驾驶舒适性分析 被引量:2
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作者 梁波 牛佳安 张红杰 《地下空间与工程学报》 CSCD 北大核心 2024年第2期657-666,700,共11页
为了更准确地评价公路隧道入口段驾驶员的视觉舒适性,以隧道入口段的驾驶员视觉特性为研究对象,在云南上鹤高速公路的野鸭塘1号、2号和3号隧道开展实车试验,采集驾驶员的注视与扫视时间、视点位置、瞳孔直径等眼动参数,并依次对20名驾... 为了更准确地评价公路隧道入口段驾驶员的视觉舒适性,以隧道入口段的驾驶员视觉特性为研究对象,在云南上鹤高速公路的野鸭塘1号、2号和3号隧道开展实车试验,采集驾驶员的注视与扫视时间、视点位置、瞳孔直径等眼动参数,并依次对20名驾驶员进行问卷调查。基于试验数据和问卷调查结果,提出扫视路径速度指标并验证其合理性。结果表明:扫视路径速度能够有效地对隧道入口段的驾驶视觉舒适性进行评价;当隧道照明条件相同时,新型蓄能反光发光材料能够使驾驶员的平均扫视路径速度降低50.62%,峰值扫视路径速度降低40.32%。通过对视觉舒适指标的关联性分析,进一步表明:扫视路径速度与驾驶员的视觉舒适性呈反比关系;随着隧道入口光环境质量的提高,驾驶员的扫视时间占比增加,进而扫视所用时间变长,扫视路径速度减慢,此时驾驶员的视觉舒适性较高有利于安全行驶,反之则不利于行车安全。 展开更多
关键词 隧道工程 扫视路径速度 实车试验 隧道入口段 视觉舒适性
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温度应力路径对原状海洋土强度特性影响研究
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作者 张鑫蕊 孔纲强 杨庆 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第2期357-365,共9页
室内温度和海底原位温度的差异导致传统测量所得海洋土物理力学参数存在一定差异。基于温控三轴仪,对我国南海原状海洋土进行了固结不排水剪切试验,实测了海洋土体变、强度、孔压以及模量的变化,探讨温度、温度循环、围压、超固结比等... 室内温度和海底原位温度的差异导致传统测量所得海洋土物理力学参数存在一定差异。基于温控三轴仪,对我国南海原状海洋土进行了固结不排水剪切试验,实测了海洋土体变、强度、孔压以及模量的变化,探讨温度、温度循环、围压、超固结比等因素对原状海洋土力学性质的影响规律。试验结果表明:升温梯度增大会使正常固结海洋土热固结程度增大,其对应的排水体积和强度也增大;升温对超固结海洋土的排水体积具有增强作用,而温度降低了海洋土的强度;温度循环作用对超固结海洋土的排水体积具有增强作用,其对应的强度也增大;本文试验条件下,当OCR=1时,海洋土25℃下不排水抗剪强度测量结果比5℃下测量结果提高8.0%;当OCR=4时,海洋土25℃下不排水抗剪强度测量结果比5℃下测量结果降低1.9%;经过温度循环5℃—45℃—5℃后的抗剪强度比5℃提高了11.9%;4次或10次温度循环后分别提高了13.8%和17.8%。 展开更多
关键词 海洋土 强度特性 应力路径 温度效应 三轴试验
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基于路径相似表与个体迁移策略的多路径覆盖测试
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作者 钱忠胜 孙志旺 +4 位作者 俞情媛 秦朗悦 蒋鹏 万子珑 王亚惠 《计算机科学与探索》 CSCD 北大核心 2024年第4期947-962,共16页
将遗传算法用于多路径覆盖测试中是个研究热点,在新旧种群迭代过程中,旧种群中可能包含其他子种群的优秀个体,这部分个体未被充分利用,造成资源浪费;同时,种群中的个体数会远大于可达路径数,而每个个体都会经过某一条可达路径,这样会有... 将遗传算法用于多路径覆盖测试中是个研究热点,在新旧种群迭代过程中,旧种群中可能包含其他子种群的优秀个体,这部分个体未被充分利用,造成资源浪费;同时,种群中的个体数会远大于可达路径数,而每个个体都会经过某一条可达路径,这样会有多个个体经过同一条路径,导致重复计算个体与目标路径的相似度。基于此,提出结合路径相似表与个体迁移的多路径覆盖测试方法以提高测试效率。通过路径相似表存储已计算得到的路径相似度值,避免该值被重复计算,减少测试时间。在进化过程中,将个体路径与其他目标路径进行比较,若相似度达到阈值,则将此优秀个体迁移至该路径对应的子种群中,提高个体利用率并减少进化代数。由实验可知,该方法与其他六种同类经典方法在八个程序上的平均生成时间降低最高达44.64%,最低为2.64%,平均进化代数降低最高达35.08%,最低为6.13%,故该方法有效地提高了测试效率。 展开更多
关键词 测试用例 路径相似表 个体迁移 多路径覆盖 多种群遗传算法
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基于电阻的冻结砂砾土孔隙冰压融效应研究
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作者 贾海梁 王亚彪 +4 位作者 魏尧 胡彬华 金龙 董元宏 唐丽云 《岩土力学》 EI CAS CSCD 北大核心 2024年第8期2221-2231,2241,共12页
为验证冻结砂砾土压缩过程中是否存在压融效应,对不同含水(冰)状态与不同冻结温度的砂砾土进行无侧限压缩试验和电阻测试,通过核磁共振测定饱和砂砾土的未冻水含量。结果表明:(1)砂砾土压缩过程电阻均先快速降低后趋缓,仅有干燥样品在... 为验证冻结砂砾土压缩过程中是否存在压融效应,对不同含水(冰)状态与不同冻结温度的砂砾土进行无侧限压缩试验和电阻测试,通过核磁共振测定饱和砂砾土的未冻水含量。结果表明:(1)砂砾土压缩过程电阻均先快速降低后趋缓,仅有干燥样品在应力峰值点后出现电阻增大的现象;(2)电阻快速降低阶段干燥样品的电阻降低率小于饱和冻结样品,−4℃饱和样品该值为26.8%,其值为相同温度下干燥样品的4倍;(3)随温度降低,电阻快速降低阶段的降低率先增加后减小;(4)随温度降低,自由水与毛细水的相对含量快速减小,吸附水的相对含量先小幅增加后缓慢降低。分析认为:冻结砂砾土压缩过程中存在压融效应,这导致样品在受荷过程中高应力区未冻水含量增大,而融水会沿未冻水膜向低应力区的孔隙迁移、复冰进而改变孔隙结构;冻结温度在−2~−4℃区间附近,压融效应更容易发生。 展开更多
关键词 冻结砂砾土 压融效应 无侧限压缩试验 电阻 导电路径
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面向智能航行避碰决策与规划的虚拟仿真测试技术研究
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作者 刘佳仑 杨帆 +2 位作者 谢玲利 李诗杰 王腾飞 《系统仿真学报》 CAS CSCD 北大核心 2024年第8期1780-1789,共10页
研究了面向智能航行避碰决策与规划的虚拟仿真测试技术。介绍了智能航行在货运船舶中的应用需求,分析了当下避碰决策策略、路径规划算法以及避碰决策与规划测试技术的研究现状。面向货运船舶智能航行避碰决策与规划能力,基于避碰规则中... 研究了面向智能航行避碰决策与规划的虚拟仿真测试技术。介绍了智能航行在货运船舶中的应用需求,分析了当下避碰决策策略、路径规划算法以及避碰决策与规划测试技术的研究现状。面向货运船舶智能航行避碰决策与规划能力,基于避碰规则中的会遇态势划分,结合四元船舶领域和贝塞尔曲线插值理论,提出了一种智能航行避碰决策与规划算法。构建了一种基于虚拟仿真环境的避碰决策与规划算法仿真测试方法,通过AIS(automatic identification system)模拟器模拟目标船的状态数据,结合船载综合导航系统(integrated navigation system,INS)实现了避碰决策与规划算法的测试。通过复杂水域仿真测试验证了所提算法的有效性和可行性,为货运船舶智能航行功能的开发与实践提供了参考。 展开更多
关键词 智能航行 避碰决策 路径规划 虚拟仿真 测试技术
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不同加卸载路径下灵敏性粉土的变形特性
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作者 卢瑞娜 余蓉 +2 位作者 高原 石雪英 巩天真 《地下空间与工程学报》 CSCD 北大核心 2024年第2期426-436,共11页
山西汾河中游一级阶地的施工中发现,饱和粉土地基受扰动后会产生很大的附加沉降,且迟迟不能稳定,表现出灵敏性。基于一维固结蠕变试验研究不同的加卸载路径对灵敏性粉土变形特性的影响,结果表明:加卸载路径和加卸荷比是影响压缩曲线的... 山西汾河中游一级阶地的施工中发现,饱和粉土地基受扰动后会产生很大的附加沉降,且迟迟不能稳定,表现出灵敏性。基于一维固结蠕变试验研究不同的加卸载路径对灵敏性粉土变形特性的影响,结果表明:加卸载路径和加卸荷比是影响压缩曲线的重要因素;压缩曲线在出现转折时对应的应力为结构屈服应力;加荷比越大,同级荷载下沉降值、固结系数、次固结系数和主固结比都会增大,同时其压缩曲线越趋近于线性,特征转折点消失,但加荷比越大,可大大减少工期;预压荷载的大小和卸荷比都会影响灵敏性粉土的回弹量,预压荷载大于结构屈服应力时,卸荷比越大,回弹量越大,因此需要采取分级卸载方法减小回弹量,保证预压效果;目标荷载小于结构屈服应力时,超载预压法降低工后沉降效果显著。 展开更多
关键词 加卸载路径 灵敏性粉土 一维固结蠕变试验 结构屈服应力
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有机工质向心透平气动设计与性能优化研究
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作者 卢绪祥 宋增 +2 位作者 刘瑞 丁海霞 李逸轩 《动力工程学报》 CAS CSCD 北大核心 2024年第8期1181-1188,共8页
为提升有机工质向心透平的效率与性能,对400 kW有机工质向心透平进行了一维气动设计。在一维气动设计结果的基础上进行建模,并结合三维数值模拟预测了有机工质向心透平在设计工况下的性能。以向心透平等熵效率为目标,采用均匀试验法对... 为提升有机工质向心透平的效率与性能,对400 kW有机工质向心透平进行了一维气动设计。在一维气动设计结果的基础上进行建模,并结合三维数值模拟预测了有机工质向心透平在设计工况下的性能。以向心透平等熵效率为目标,采用均匀试验法对动叶轮的子午流道进行优化设计。结果表明:与原始向心透平相比,优化后的向心透平流场压力分布层次更加分明,整体熵增减小,产生的摩擦损失、尾迹损失明显减小,叶片做功能力增大,向心透平内部的流动情况得到了改善,等熵效率由原来的82.33%提高到85.92%,输出功率也增大了18.04 kW。 展开更多
关键词 向心透平 子午流道 性能优化 均匀试验法 数值模拟
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PB840呼吸机气路分析及故障维修
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作者 曲超 李首峰 《中国医疗设备》 2024年第7期176-180,共5页
呼吸机是一种能替代患者自主通气的医疗仪器,广泛应用于呼吸衰竭患者、呼吸支持治疗以及急救复苏过程,是医院急诊、重症加强护理病房最重要的抢救仪器。本文介绍了2例PB840呼吸机故障,故障现象均为呼吸机报警、停止送气,报警代码相似。... 呼吸机是一种能替代患者自主通气的医疗仪器,广泛应用于呼吸衰竭患者、呼吸支持治疗以及急救复苏过程,是医院急诊、重症加强护理病房最重要的抢救仪器。本文介绍了2例PB840呼吸机故障,故障现象均为呼吸机报警、停止送气,报警代码相似。第1例故障经过呼吸机扩展自检(Extenden Self Test,EST)后分析自检数据,发现为呼出端流量传感器Q3故障,经过柠檬酸浸泡处理Q3后故障解除;第2例故障为氧气调零流量检测失败,具体原因为氧比例电磁阀故障,更换配件后故障解除。通过两例故障提示维修人员需熟悉仪器的气路图,熟练掌握呼吸机EST方法,提高维修准确度。 展开更多
关键词 PB840呼吸机 气路分析 扩展自检 流量传感器
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基本路径测试技术及应用研究
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作者 明德廷 李娟 +1 位作者 王兴宇 谭亮 《计算机应用文摘》 2024年第7期74-76,81,共4页
基本路径测试法是一种白盒测试方法,文章将程序流程图映射成流图,探讨了程序的3种基本结构映射成流图的方法,计算了流图的环形复杂度并确定了基本测试路径,从而为每条基本路径设计了测试用例。实践证明,基本路径测试法适用于执行路径较... 基本路径测试法是一种白盒测试方法,文章将程序流程图映射成流图,探讨了程序的3种基本结构映射成流图的方法,计算了流图的环形复杂度并确定了基本测试路径,从而为每条基本路径设计了测试用例。实践证明,基本路径测试法适用于执行路径较多的程序,通过选择有代表性的路径进行测试,可有效提高测试效率。 展开更多
关键词 基本路径 白盒测试 流图 环形复杂度
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结合SVM与XGBoost的链式多路径覆盖测试用例生成
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作者 钱忠胜 俞情媛 +3 位作者 张丁 姚昌森 秦朗悦 成轶伟 《软件学报》 EI CSCD 北大核心 2024年第6期2795-2820,共26页
机器学习方法可很好地与软件测试相结合,增强测试效果,但少有学者将其运用于测试数据生成方面.为进一步提高测试数据生成效率,提出一种结合SVM(support vector machine)和XGBoost(extreme gradient boosting)的链式模型,并基于此模型借... 机器学习方法可很好地与软件测试相结合,增强测试效果,但少有学者将其运用于测试数据生成方面.为进一步提高测试数据生成效率,提出一种结合SVM(support vector machine)和XGBoost(extreme gradient boosting)的链式模型,并基于此模型借助遗传算法实现多路径测试数据生成.首先,利用一定样本训练若干个用于预测路径节点状态的子模型(SVM和XGBoost),通过子模型的预测精度值筛选最优子模型,并根据路径节点顺序将其依次链接,形成一个链式模型C-SVMXGBoost(chained SVM and XGBoost).在利用遗传算法生成测试用例时,使用训练好的链式模型代替插桩法获取测试数据覆盖路径(预测路径),寻找预测路径与目标路径相似的路径集,对存在相似路径集的预测路径进行插桩验证,获取精确路径,计算适应度值.在交叉变异过程中引入样本集中路径层级深度较大的优秀测试用例进行重用,生成覆盖目标路径的测试数据.最后,保留进化生成中产生的适应度较高的个体,更新链式模型C-SVMXGBoost,进一步提高测试效率.实验表明,C-SVMXGBoost较其他各对比链式模型更适合解决路径预测问题,可提高测试效率.并且通过与已有经典方法相比,所提方法在覆盖率上提高可达15%,平均进化代数也有所降低,在较大规模程序上其降低百分比可达65%. 展开更多
关键词 测试用例 SVM XGBoost 链式模型 多路径覆盖
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我国中考体育政策执行的制约因素与路径选择——基于史密斯政策执行过程模型的视角
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作者 孙长良 《沈阳体育学院学报》 CSSCI 北大核心 2024年第1期44-49,99,共7页
中考体育政策执行效果直接影响着我国中考体育的改革与发展。基于史密斯政策执行过程模型,运用文献资料法与逻辑分析法,对当前我国中考体育政策的实施过程进行梳理与分析。研究认为,政策有效推行不畅、机构运行效果滞后、目标认知偏差... 中考体育政策执行效果直接影响着我国中考体育的改革与发展。基于史密斯政策执行过程模型,运用文献资料法与逻辑分析法,对当前我国中考体育政策的实施过程进行梳理与分析。研究认为,政策有效推行不畅、机构运行效果滞后、目标认知偏差和外界阻力较大等都是阻滞中考体育政策有效执行的重要因素。提出中考体育政策执行的路径:强化政策制定体系,保证政策科学合理;完善政策执行机制,发挥多元协同作用;激发群体主动性,满足群体利益需求;营造良好政策环境,提升宣传保障效能。 展开更多
关键词 中考体育 政策执行 制约因素 路径选择 史密斯模型
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空间引力波星载望远镜测试与评估技术研究进展 被引量:1
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作者 张兰强 曾意 +5 位作者 吴小虎 杨金生 阮晓莉 辛强 顾乃庭 饶长辉 《光电工程》 CAS CSCD 北大核心 2024年第2期6-21,共16页
在空间引力波探测任务中,星载望远镜承担太空超长干涉光路双向光束准直的重要作用。空间引力波探测对星载望远镜提出了pm级光程稳定性和低于10^(-10)级后向杂散光水平的极高要求。超高水平指标要求超过了当前测试技术的精度极限,因此,... 在空间引力波探测任务中,星载望远镜承担太空超长干涉光路双向光束准直的重要作用。空间引力波探测对星载望远镜提出了pm级光程稳定性和低于10^(-10)级后向杂散光水平的极高要求。超高水平指标要求超过了当前测试技术的精度极限,因此,针对星载望远镜发展测试与评估技术并开展系统超高精度测试是空间引力波探测计划成功的重要前提。本文在概述国内外在研的空间引力波探测星载望远镜研制情况的基础上,重点围绕星载望远镜的核心技术指标——光程稳定性和后向杂散光,介绍了在研望远镜的测试技术发展现状和已经取得的部分测试成果,以及各研究单位进一步的测试计划,为我国的空间引力波探测的星载望远镜测试与评估技术发展提供参考。 展开更多
关键词 空间引力波探测 星载望远镜 地面测试 光程稳定性 后向杂散光
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面向自主芯片频率扫描实速测试的扫描链分析
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作者 张锦 刘政辉 +1 位作者 扈啸 胡春媚 《电子测量与仪器学报》 CSCD 北大核心 2024年第3期122-132,共11页
随着芯片工艺的不断升级,芯片设计的频率不断提高,时延故障是引起高速芯片失效的重要因素。在硅后验证阶段,由于缺乏一种对芯片全局路径延时测量的手段,传统构建延时测量电路的方式仅能得到特定关键路径的延时变化情况,在芯片失效时无... 随着芯片工艺的不断升级,芯片设计的频率不断提高,时延故障是引起高速芯片失效的重要因素。在硅后验证阶段,由于缺乏一种对芯片全局路径延时测量的手段,传统构建延时测量电路的方式仅能得到特定关键路径的延时变化情况,在芯片失效时无法进行全面的路径延时分析。本文提出一种基于扫描链的频率扫描实速测试方法对芯片内部大量时序路径的延时进行测量并获取时序裕量。针对生成测试向量时间长,依赖专业测试设备的问题,在自研硬件平台上通过自生成多频率测试向量以及改进数据校验算法成功实现了频率扫描实速测试,对芯片测量的路径延时误差在8 ps左右。通过对不同芯片在不同温度下的实验验证了该方法对路径延时表征的有效性,为今后通过延时参数对高速芯片进行环境适应性分析、寿命预测等研究提供了一种快捷有效的方法。 展开更多
关键词 实速测试 扫描链 芯片测试 测试向量 路径延时
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