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利用LSF API实现高性能计算机集群的机时统计 被引量:6
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作者 盛乐标 周庆林 《实验科学与技术》 2014年第2期50-52,117,共4页
准确的计算机时统计是大型计算机集群执行计费政策的基础。使用wall time而非CPU time来统计计算机时是一种比较公平的方式。文中提到的利用LSF API结合C语言和Shell脚本语言进行编程,可以实现多样化、可定制的计算机时统计和报表制作,... 准确的计算机时统计是大型计算机集群执行计费政策的基础。使用wall time而非CPU time来统计计算机时是一种比较公平的方式。文中提到的利用LSF API结合C语言和Shell脚本语言进行编程,可以实现多样化、可定制的计算机时统计和报表制作,为高性能计算中心和超级计算中心的管理带来便利。 展开更多
关键词 高性能计算 集群管理 统计 计算机时
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生态符担理论视角下的异时计算机中介交际中的外语学习焦虑研究
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作者 刘欧 《外国语文研究》 2015年第4期92-100,共9页
本研究从生态语言学的角度,探究在异时计算机中介交际(Asynchronous CMC)中外语学习焦虑的来源和程度,以及环境中被感知的符担性资源与外语学习焦虑之间的关系。研究对象为126名英语中等水平学生,完成基于voxopop的语音学习任务。实验证... 本研究从生态语言学的角度,探究在异时计算机中介交际(Asynchronous CMC)中外语学习焦虑的来源和程度,以及环境中被感知的符担性资源与外语学习焦虑之间的关系。研究对象为126名英语中等水平学生,完成基于voxopop的语音学习任务。实验证明,在语音环境下,学习者的焦虑程度为中等偏弱。焦虑来源主要来自同伴间的比较,学习者对语音和语法的关注程度较高。此外,外语学习焦虑与总体符担性之间的相关性较弱,而部分个体符担性与外语学习焦虑之间相关性较强,原因是部分个体符担性与外语学习焦虑之间存在正向和负向的相关性。这也反映了环境对有感知的学习行为既有发挥其潜力的作用也有阻碍其行为的一面。本研究为未来的Asynchronous CMC环境与外语学习焦虑研究相关性研究开辟了新的渠道。 展开更多
关键词 符担性 外语学习焦虑 计算机中介交际 生态语言学
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计算机网络时滞控制仿真实验研究
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作者 宋建强 李昇平 《汕头大学学报(自然科学版)》 2003年第3期39-43,共5页
本文通过使用 Java网络编程技术 ,实现了 Matlab的网络控制功能 ,并仿真模拟 ,由控制网络引起的控制信息传输时延时 ,导致工业控制系统性能恶化的情况 。
关键词 计算机网络滞控制 网络控制 网络编程 JAVA MATLAB 计算机仿真 传输
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计算机测试形式对语言测试的影响 被引量:2
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作者 王勇旗 《韶关学院学报》 2008年第9期40-43,共4页
总结了计算机语言测试的发展现状及其优势,从测试的信度、与传统纸笔测试的对等性和实用性三个主要方面分析计算机测试所面临的挑战,并对计算机语言测试的发展前景做了初步的展望.
关键词 语言测试 计算机测试等性 效度
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超级计算环境计算配额系统设计和实现 被引量:6
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作者 牛铁 朱鹏 +1 位作者 赵毅 曹宗雁 《计算机应用》 CSCD 北大核心 2010年第12期8-9,39,共3页
在超级计算环境中,为避免计算资源滥用,确保每个用户有机会利用超级计算机求解生产、科研中的复杂问题,产出更多成果,在定期采集、解析作业日志的基础上,通过LSF API、shell编程,设计和实现了一套计算配额系统,用于对用户计算资源的配... 在超级计算环境中,为避免计算资源滥用,确保每个用户有机会利用超级计算机求解生产、科研中的复杂问题,产出更多成果,在定期采集、解析作业日志的基础上,通过LSF API、shell编程,设计和实现了一套计算配额系统,用于对用户计算资源的配额、限制及使用情况统计分析。该系统已运行于中国科学院超级计算环境百万亿次超级计算机深腾7000中,效果良好。 展开更多
关键词 超级计算环境 LSF 计算配额 计算机时 深腾7000
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基于单片机晶振的守时研究 被引量:11
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作者 原玉磊 夏天倚 陈渊 《电子测量技术》 2011年第11期19-22,共4页
为了简化天文观测守时设备,利用普通晶振和51单片机计数器实现了1个守时时钟,通过单片机串口向外输出秒脉冲和时间。以高精度的计算机64位计数器时间作为准确时间,对该时钟的稳定性进行分析。通过对近25个h时间比对数据的分析,得出以下... 为了简化天文观测守时设备,利用普通晶振和51单片机计数器实现了1个守时时钟,通过单片机串口向外输出秒脉冲和时间。以高精度的计算机64位计数器时间作为准确时间,对该时钟的稳定性进行分析。通过对近25个h时间比对数据的分析,得出以下结论:该时钟秒钟速非常稳定,变化不超过0.5μs;24个h的小时钟速互差不超过1ms;经过2min的时间比对即可确定准确的钟差钟速。证明该时钟满足一等天文测量对时间的要求,为野外天文测量时间系统的微型化提供了参考。 展开更多
关键词 晶振 计算机时 单片机 钟差钟速 天文测量
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聋哑儿童视觉反应时对比研究 被引量:3
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作者 陈容 白春玉 +1 位作者 张迪 冯娟 《中国公共卫生》 CAS CSCD 北大核心 2004年第12期1429-1430,共2页
目的 探讨聋哑儿童与正常儿童视觉反应时的差别及影响因素。方法 采用计算机反应时测试软件系统 ,对 93名 7~ 13岁聋哑学生进行了视觉反应时的测定及分析。结果 聋哑儿童视觉简单和视觉复杂反应时的各项测试指标均慢于正常儿童 ,2... 目的 探讨聋哑儿童与正常儿童视觉反应时的差别及影响因素。方法 采用计算机反应时测试软件系统 ,对 93名 7~ 13岁聋哑学生进行了视觉反应时的测定及分析。结果 聋哑儿童视觉简单和视觉复杂反应时的各项测试指标均慢于正常儿童 ,2组间有非常显著差异 (P <0 0 1) ;视觉对比反应时的最快反应时、反应错漏率 ,2组间有显著性差异 (P <0 0 5或P <0 0 1)。结论 聋哑儿童视觉反应时慢于正常儿童。提高聋哑儿童视觉信息处理能力对其智力开发具有重要意义。 展开更多
关键词 计算机反应测定 聋哑儿童 视觉
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人机口头对话时代的到来 被引量:1
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作者 William Crossman 吕吉尔 《世界科学》 2000年第10期29-31,共3页
信息技术专家宣称,到2050年,人们将不再需要读写。计算机将对我们的声音作出反应。
关键词 输入输出计算机 功能 人机口头对话
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动力降尺度方法在辐射雾大涡模拟中的应用
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作者 林继配 张庆红 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2017年第4期607-616,共10页
针对大涡模拟(LES)计算精确但耗费大量计算机资源的特点,采用动力降尺度的方法,把传统的边界层(PBL)方案与LES模拟相结合,利用WRFV3.7模式四重到五重嵌套网格,以华北地区一次辐射雾为例进行模拟,试图保留LES计算精确的特点,并减少计算... 针对大涡模拟(LES)计算精确但耗费大量计算机资源的特点,采用动力降尺度的方法,把传统的边界层(PBL)方案与LES模拟相结合,利用WRFV3.7模式四重到五重嵌套网格,以华北地区一次辐射雾为例进行模拟,试图保留LES计算精确的特点,并减少计算机时。结果表明,动力降尺度方法能够准确地预报雾的发生,与同样水平分辨率的LES模拟相比,四层嵌套网格节省47.02%计算机时,五层嵌套网格节省67.67%计算机时,可以为未来高分辨率业务预报系统的LES模拟实现提供一种可能性。 展开更多
关键词 辐射雾 大涡模拟 边界层 降尺度 计算机时
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Rescheduling Problems with Bicriteria 被引量:3
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作者 慕运动 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第3期349-356,共8页
In the rescheduling on a single machine,a set of original jobs has already been scheduled to minimize some cost objective,when a new set of jobs arrives and creates a disruption.The decision maker needs to insert the ... In the rescheduling on a single machine,a set of original jobs has already been scheduled to minimize some cost objective,when a new set of jobs arrives and creates a disruption.The decision maker needs to insert the new jobs into the existing schedule without excessively disrupting it.In this paper,we consider hierarchical optimization between the scheduling cost of all the jobs and the degree of this disruption.For every problem,we provide either a polynomial time algorithm or an intractable result. 展开更多
关键词 RESCHEDULING hierarchical optimization time disruption sequence disruption single machine
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Cryptanalysis of Cryptosystems Based on General Linear Group 被引量:1
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作者 Jianwei Jia Jinhui Liu Huanguo Zhang 《China Communications》 SCIE CSCD 2016年第6期217-224,共8页
Advances in quantum computers threaten to break public key cryptosystems such as RSA, ECC, and EIGamal on the hardness of factoring or taking a discrete logarithm, while no quantum algorithms are found to solve certai... Advances in quantum computers threaten to break public key cryptosystems such as RSA, ECC, and EIGamal on the hardness of factoring or taking a discrete logarithm, while no quantum algorithms are found to solve certain mathematical problems on non-commutative algebraic structures until now. In this background, Majid Khan et al.proposed two novel public-key encryption schemes based on large abelian subgroup of general linear group over a residue ring. In this paper we show that the two schemes are not secure. We present that they are vulnerable to a structural attack and that, it only requires polynomial time complexity to retrieve the message from associated public keys respectively. Then we conduct a detailed analysis on attack methods and show corresponding algorithmic description and efficiency analysis respectively. After that, we propose an improvement assisted to enhance Majid Khan's scheme. In addition, we discuss possible lines of future work. 展开更多
关键词 CRYPTOGRAPHY post quantum computational cryptography CRYPTANALYSIS non-abelian algebraic structures linear equations
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Computer Programs for Prediction of Mining Area Deformation with Time Factor Taken into Consideration 被引量:2
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作者 BIALEK Jan 《Journal of China University of Mining and Technology》 2002年第1期6-11,共6页
This paper discussed the current of works on computerisation of all problems related to mining subsidence, including the time factor,carried out in the Division of Mining Geodesy of Technical University of Silesia, Po... This paper discussed the current of works on computerisation of all problems related to mining subsidence, including the time factor,carried out in the Division of Mining Geodesy of Technical University of Silesia, Poland. First, the formulas implemented in the programs were presented. These formulas considerably increase the description accuracy of final deformations by taking into uncaved strip along extraction rib (extraction margin). They also improve the deformation description of areas located far from the extraction place. Then, the research results aiming to improving the description of deformation with time were introduced. Finally, the Windows based version of the program for the creation of mining geological opinions were presented in the form accepted by Mining Offices of Poland. 展开更多
关键词 mining subsidence PROGRAM time factor
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Processing of 8-Channel Synchronous Electro-Cardiograph
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作者 赵捷 韩月秋 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期66-70,共5页
A real time algorithm is presented here to recognize and analyze 8 channel simultaneous electro cardiograph(ECG). The algorithm transforms 8 channel simultaneous ECG into three orthogonal vectors and spatial veloc... A real time algorithm is presented here to recognize and analyze 8 channel simultaneous electro cardiograph(ECG). The algorithm transforms 8 channel simultaneous ECG into three orthogonal vectors and spatial velocity first, then forms the spatial velocity sample, and uses this spatial velocity sample to recognize each beat. The algorithm computes the averaged parameters by using averaged spatial velocity and the averaged ECG and the current parameters by using the current beat period and current width of QRS. The algorithm can recognize P, QRS and T onsets and ends of simultaneous 12 lead ECG precisely, and some arrhythmias such as premature ventricular beat, ventricular escape beat, R on T, bigeminy, trigeminy. The algorithm software works well on a real 8 channel ECG system and meets the demands of designing. 展开更多
关键词 multi lead electro cardiograph embedded system real time computer processing
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Deterministic and randomized scheduling problems under the lp norm on two identical machines 被引量:5
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作者 林凌 谈之奕 何勇 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第1期20-26,共7页
Parallel machine scheduling problems, which are important discrete optimization problems, may occur in many applications. For example, load balancing in network communication channel assignment, parallel processing in... Parallel machine scheduling problems, which are important discrete optimization problems, may occur in many applications. For example, load balancing in network communication channel assignment, parallel processing in large-size computing, task arrangement in flexible manufacturing systems, etc., are multiprocessor scheduling problem. In the traditional parallel machine scheduling problems, it is assumed that the problems are considered in offline or online environment. But in practice, problems are often not really offline or online but somehow in-between. This means that, with respect to the online problem, some further information about the tasks is available, which allows the improvement of the performance of the best possible algorithms. Problems of this class are called semi-online ones. In this paper, the semi-online problem P2|decr|lp (p>1) is considered where jobs come in non-increasing order of their processing times and the objective is to minimize the sum of the lp norm of every machine’s load. It is shown that LS algorithm is optimal for any lp norm, which extends the results known in the literature. Furthermore, randomized lower bounds for the problems P2|online|lp and P2|decr|lp are presented. 展开更多
关键词 SEMI-ONLINE SCHEDULING RANDOMIZATION Competitive ratio
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Effect of Timing of Tracheotomy on Clinical Outcomes: an Update Meta-analysis Including 11 Trials 被引量:10
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作者 Liang Shan Rui Zhang Lian-di Li 《Chinese Medical Sciences Journal》 CAS CSCD 2013年第3期159-166,共8页
Objective To estimate the relative effect of early vs. late tracheotomy on clinical end-points in unselected intensive care unit (ICU) patients undergoing mechanical ventilation. Methods We searched electronic data... Objective To estimate the relative effect of early vs. late tracheotomy on clinical end-points in unselected intensive care unit (ICU) patients undergoing mechanical ventilation. Methods We searched electronic databases (up to February 27, 2013) for both randomized control trials and observational studies satisfying the predefined inclusion criteria. 展开更多
关键词 intensive care unit artificial respiration TRACHEOTOMY META-ANALYSIS
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Computer simulation of evacuation in underground coal mines 被引量:4
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作者 JI Jingwei ZHANG Jlngyao +1 位作者 CHEN Jinlin WU Shuang 《Mining Science and Technology》 EI CAS 2010年第5期677-681,共5页
In order to study the evacuation behavior of miners during accidents,we analyzed the rational layout of a safe chamber,and improved evacuation efficiency.A visual model of evacuation was developed and used to simulate... In order to study the evacuation behavior of miners during accidents,we analyzed the rational layout of a safe chamber,and improved evacuation efficiency.A visual model of evacuation was developed and used to simulate the evacuation process of mines,given their special underground environments.In our simulation,the working faces of a coal mine and nearby tunnels were divided into 0.5 m×0.5 m grids to reflect the location of occupants and obstacles.Based on a "flow potential of the occupant",we determined the direction of movement and routes of occupants.In the model,evacuation speed changed as a function of crowd density,with an average speed of 1.30 m/s.The model also takes into account detection time of the disaster and the personnel response time.Evacuation time,exit flow rate and evacuation path were obtained by simulation.The results indicate that using simulation technology can present a more visual evacuation process and show the behavior of occupants.Our establishment of a mine safety evacuation system has merit as reference value. 展开更多
关键词 computer simulation EVACUATION MODEL coal mine
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An Optimal Algorithm for a Class of Parallel Machines Scheduling Problem
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作者 常俊林 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第3期17-20,共4页
This paper considers the parallel machines scheduling problem where jobs are subject to different release times. A constructive heuristic is first proposed to solve the problem in a modest amount of computer time. In ... This paper considers the parallel machines scheduling problem where jobs are subject to different release times. A constructive heuristic is first proposed to solve the problem in a modest amount of computer time. In general, the quality of the solutions provided by heuristics degrades with the increase of the probiem’s scale. Combined the global search ability of genetic algorithm, this paper proposed a hybrid heuristic to improve the quality of solutions further. The computational results show that the hybrid heuristic combines the advantages of heuristic and genetic algorithm effectively and can provide very good solutions to some large problems in a reasonable amount of computer time. 展开更多
关键词 optimal scheduling release time HEURISTIC genetic algorithm
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细胞的“逆分裂”现象 被引量:1
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作者 俞索静 肖鲁伟 吴承亮 《浙江中医学院学报》 2004年第5期1-3,共3页
在人体组织细胞的体外培养中 ,采用自行设计组建的计算机显微缩时电影系统 (computerTime lapseMicrocin ematography) ,反复记录到细胞分裂后的再融合现象。这种细胞由分裂随即又发生融合的过程 ,可能是一种特殊的“自然融合”(natural... 在人体组织细胞的体外培养中 ,采用自行设计组建的计算机显微缩时电影系统 (computerTime lapseMicrocin ematography) ,反复记录到细胞分裂后的再融合现象。这种细胞由分裂随即又发生融合的过程 ,可能是一种特殊的“自然融合”(naturalfusion) ,或是细胞的一种“逆分裂”(contra division)现象。 展开更多
关键词 人体组织细胞 体外培养 计算机显微缩电影系统 细胞分裂 细胞逆分裂
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Adaptive learning with guaranteed stability for discrete-time recurrent neural networks 被引量:1
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作者 邓华 吴义虎 段吉安 《Journal of Central South University of Technology》 EI 2007年第5期685-689,共5页
To avoid unstable learning, a stable adaptive learning algorithm was proposed for discrete-time recurrent neural networks. Unlike the dynamic gradient methods, such as the backpropagation through time and the real tim... To avoid unstable learning, a stable adaptive learning algorithm was proposed for discrete-time recurrent neural networks. Unlike the dynamic gradient methods, such as the backpropagation through time and the real time recurrent learning, the weights of the recurrent neural networks were updated online in terms of Lyapunov stability theory in the proposed learning algorithm, so the learning stability was guaranteed. With the inversion of the activation function of the recurrent neural networks, the proposed learning algorithm can be easily implemented for solving varying nonlinear adaptive learning problems and fast convergence of the adaptive learning process can be achieved. Simulation experiments in pattern recognition show that only 5 iterations are needed for the storage of a 15×15 binary image pattern and only 9 iterations are needed for the perfect realization of an analog vector by an equilibrium state with the proposed learning algorithm. 展开更多
关键词 recurrent neural networks adaptive learning nonlinear discrete-time systems pattern recognition
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A Fault Detection and Isolation Scheme Based on Parity Space Method for Discrete Time-delay System 被引量:1
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作者 王红雨 田作华 +1 位作者 施颂椒 翁正新 《Journal of Donghua University(English Edition)》 EI CAS 2008年第3期304-307,共4页
A Fault detection and isolation(FDI)scheme for discrete time-delay system is proposed in this paper,which can not only detect but also isolate the faults.A time delay operator is introduced to resolve the problem bro... A Fault detection and isolation(FDI)scheme for discrete time-delay system is proposed in this paper,which can not only detect but also isolate the faults.A time delay operator is introduced to resolve the problem brought by the time-delay system.The design and computation for the FDI system is carried by computer math tool Maple,which can easily deal with the symbolic computation.Residuals in the form of parity space can be deduced from the recursion of the system equations.Further more,a generalized residual set is created using the freedom of the parity space redundancy.Thus,both fault detection and fault isolation have been accomplished.The proposed method has been verified by a numerical example. 展开更多
关键词 fault detection and isolation parity space time-delay system
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