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摩擦轮提升选型设计计算方法的改进
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作者 李玉瑾 《煤矿设计》 北大核心 1989年第5期21-30,共10页
《煤矿设计》1988年第4期刊登的“摩擦提升选型设计计算新法”一文指出:从防滑入手,先确定空载侧最小张力,再选择钢丝绳并计算所需配重,可使设计一次完成的新法.这一思路很好,但不完善,此法不能避免设计返工.众所周知,摩擦轮提升设备中... 《煤矿设计》1988年第4期刊登的“摩擦提升选型设计计算新法”一文指出:从防滑入手,先确定空载侧最小张力,再选择钢丝绳并计算所需配重,可使设计一次完成的新法.这一思路很好,但不完善,此法不能避免设计返工.众所周知,摩擦轮提升设备中提升机、钢丝绳和电动机的诸多约束条件中之一不满足都要造成设计返工.若只从防滑角度考虑钢丝绳安全系数的约束条件,并不能保证提升机、钢丝绳和电动机不返工.在设计中我们曾经从提升机。 展开更多
关键词 摩擦轮 提升设备 选型 设计计算法
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矿井地质网格界面计算机辅助设计法
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《同煤科技》 1989年第4期55-57,共3页
关键词 煤矿 矿井地质 网格界面 计算机辅助设计
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基于正交设计的灯泡贯流式机组关闭规律优化 被引量:4
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作者 陈云良 徐永 +1 位作者 杜敏 杨华 《排灌机械工程学报》 EI CSCD 北大核心 2015年第4期322-326,共5页
建立以转速升高、导叶前水压力以及轴向水推力组成的过渡过程目标函数,选取了相应的权重系数.采用适于多因素、多水平的正交设计计算法进行机组关闭规律寻优.给定导叶第一段关闭时间,以第二段关闭时间、分段点开度和桨叶关闭时间为因子... 建立以转速升高、导叶前水压力以及轴向水推力组成的过渡过程目标函数,选取了相应的权重系数.采用适于多因素、多水平的正交设计计算法进行机组关闭规律寻优.给定导叶第一段关闭时间,以第二段关闭时间、分段点开度和桨叶关闭时间为因子,每个因子取4水平进行正交设计计算.研究表明:最佳导叶、桨叶关闭规律下,转速升高、导叶前水压力、轴向水推力以及尾水管进口压力等过渡过程品质较优化前有明显的改善.桨叶缓慢关闭能减小引水管中水击压力以及尾水管进口的真空度,可显著降低机组转速升高及轴向反推力.通过正交设计计算法可以寻求较佳的关闭规律,使灯泡贯流式机组在甩负荷时获得较好的过渡过程,对保障电站安全稳定运行具有指导意义. 展开更多
关键词 灯泡贯流式机组 甩负荷 过渡过程 关闭规律 正交设计计算法
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APPROXIMATION TECHNIQUES FOR APPLICATION OF GENETIC ALGORITHMS TO STRUCTURAL OPTIMIZATION 被引量:1
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作者 金海波 丁运亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期147-154,共8页
Although the genetic algorithm (GA) has very powerful robustness and fitness, it needs a large size of population and a large number of iterations to reach the optimum result. Especially when GA is used in complex str... Although the genetic algorithm (GA) has very powerful robustness and fitness, it needs a large size of population and a large number of iterations to reach the optimum result. Especially when GA is used in complex structural optimization problems, if the structural reanalysis technique is not adopted, the more the number of finite element analysis (FEA) is, the more the consuming time is. In the conventional structural optimization the number of FEA can be reduced by the structural reanalysis technique based on the approximation techniques and sensitivity analysis. With these techniques, this paper provides a new approximation model-segment approximation model, adopted for the GA application. This segment approximation model can decrease the number of FEA and increase the convergence rate of GA. So it can apparently decrease the computation time of GA. Two examples demonstrate the availability of the new segment approximation model. 展开更多
关键词 approximation techniques segment approximation model genetic algorithms structural optimization sensitivity analysis
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Iterative Block DFE for Underwater Acoustic Single Carrier System 被引量:4
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作者 Sun Haixin Guo Yuhui +1 位作者 Kuai Xiaoyan Cheng En 《China Communications》 SCIE CSCD 2012年第7期121-126,共6页
Abstract: In order to gain a better performance and reduce the computational complexity of the filter design in the underwater acoustic single car rier system, a new Iterative Block DFE (IBDFE) is proposed, which o... Abstract: In order to gain a better performance and reduce the computational complexity of the filter design in the underwater acoustic single car rier system, a new Iterative Block DFE (IBDFE) is proposed, which operates iteratively on blocks of the received signal, and fully implements its filtering operations by Discrete Fourier Trans forms (DFTs). Two design methods are consid ered for IBDFE: one is HDIBDFE, and the oth er is SDIBDFE. In this paper, the first one is a dopted. In this scheme, 展开更多
关键词 underwater acoustic system single carrier IBDFE
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Task-and-role-based access-control model for computational grid
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作者 龙涛 《Journal of Chongqing University》 CAS 2007年第4期249-255,共7页
Access control in a grid environment is a challenging issue because the heterogeneous nature and independent administration of geographically dispersed resources in grid require access control to use fine-grained poli... Access control in a grid environment is a challenging issue because the heterogeneous nature and independent administration of geographically dispersed resources in grid require access control to use fine-grained policies. We established a task-and-role-based access-control model for computational grid (CG-TRBAC model), integrating the concepts of role-based access control (RBAC) and task-based access control (TBAC). In this model, condition restrictions are defined and concepts specifically tailored to Workflow Management System are simplified or omitted so that role assignment and security administration fit computational grid better than traditional models; permissions are mutable with the task status and system variables, and can be dynamically controlled. The CG-TRBAC model is proved flexible and extendible. It can implement different control policies. It embodies the security principle of least privilege and executes active dynamic authorization. A task attribute can be extended to satisfy different requirements in a real grid system. 展开更多
关键词 computational grid task-and-role-based access control grid security role assignment
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Optimization and Control of Extractive Distillation with Heat Integration for Separating Benzene/Cyclohexane Mixtures 被引量:3
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作者 Li Lumin Tu Yangqin +2 位作者 Guo Lianjie Sun Lanyi Tian Yuanyu 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第4期117-127,共11页
In this work, the extractive distillation with heat integration process is extended to separate the pressure-insensitive benzene-cyclohexane azeotrope by using furfural as the entrainer. The optimal design of extracti... In this work, the extractive distillation with heat integration process is extended to separate the pressure-insensitive benzene-cyclohexane azeotrope by using furfural as the entrainer. The optimal design of extractive distillation process is established to achieve minimum energy requirement using the multi-objective genetic algorithm, and the results show that energy saving for this heat integration process is 15.7%. Finally, the control design is performed to investigate the system's dynamic performance, and three control structures are studied. The pressure-compensated temperature control scheme is proposed based on the first two control structures, and the dynamic responses reveal that the feed disturbances in both flow rate and benzene composition can be mitigated well. 展开更多
关键词 extractive distillation heat integration optimization genetic algorithm dynamic simulation
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Intelligent Resources Management System Design in Information Centric Networking 被引量:2
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作者 Hengyang Zhang Shixiang Zhu +2 位作者 Renchao Xie Tao Huang Yunjie Liu 《China Communications》 SCIE CSCD 2017年第8期105-123,共19页
Information centric networking(ICN) is a new network architecture that is centred on accessing content. It aims to solve some of the problems associated with IP networks, increasing content distribution capability and... Information centric networking(ICN) is a new network architecture that is centred on accessing content. It aims to solve some of the problems associated with IP networks, increasing content distribution capability and improving users' experience. To analyse the requests' patterns and fully utilize the universal cached contents, a novel intelligent resources management system is proposed, which enables effi cient cache resource allocation in real time, based on changing user demand patterns. The system is composed of two parts. The fi rst part is a fi ne-grain traffi c estimation algorithm called Temporal Poisson traffi c prediction(TP2) that aims at analysing the traffi c pattern(or aggregated user requests' demands) for different contents. The second part is a collaborative cache placement algorithm that is based on traffic estimated by TP2. The experimental results show that TP2 has better performance than other comparable traffi c prediction algorithms and the proposed intelligent system can increase the utilization of cache resources and improve the network capacity. 展开更多
关键词 information centric networking traffi c estimation cache resources allocation time series analysis intelligent analysis
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Orthogonal Array-based Uniform Latin Hypercube Design and Its Construction
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作者 杨贵军 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期179-186,共8页
Orthogonal array-based uniform Latin hypercube design(uniform OALHD) is a class of orthogonal array-based Latin hypercube designs to have the best uniformity. In this paper, we provide a less computational algorithm... Orthogonal array-based uniform Latin hypercube design(uniform OALHD) is a class of orthogonal array-based Latin hypercube designs to have the best uniformity. In this paper, we provide a less computational algorithm to construct uniform OALHD in 2-dimensional space from Bundschuh and Zhu(1993). And some uniform OALHDs are constructed by using our method. 展开更多
关键词 LHD OALHD uniform OALHD uniform design computer experiments
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Optimization of the catch bench design using a genetic algorithm 被引量:1
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作者 Ruvin Wijesinghe Dakshith You Greg 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1011-1016,共6页
Rockfalls are one of the hazards that may be associated with open pit mining. The majority of rockfalls occur due to the existing conditions of slopes, such as back break, fractures and joints. Constructing a berm on ... Rockfalls are one of the hazards that may be associated with open pit mining. The majority of rockfalls occur due to the existing conditions of slopes, such as back break, fractures and joints. Constructing a berm on the catch bench is a popular method for the mitigation of rockfall hazards in open pit mining.The width of the catch bench and the height of the berm play a major role in the open pit bench design.However, there is no systematic method currently available to optimize the size of these parameters. This study proposes a novel methodology which calculates the optimum catch bench width by integrating the rockfall simulation model and genetic algorithm into a Simulation-Optimization Model. The proposed methodology is useful when used to determine the minimum catch bench width, or the maximum overall slope angle, insuring that a sufficient factor of safety of the slope is included while maximizing the overall profitability of the open pit mine. 展开更多
关键词 Catch bench width RocFall Genetic algorithm Simulation-Optimization model
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