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高速铁路引入枢纽列控等级选择与应用的研究 被引量:9
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作者 张敏慧 谢静高 《铁路通信信号工程技术》 2020年第6期8-13,共6页
结合枢纽地区站点设置、信号系统设置特点,研究高速铁路以不同形式引入枢纽时列控等级选择的设计原则和设计方案,提出枢纽列控等级选择的特殊性要求。
关键词 高速铁路 枢纽 控等级选择
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随机选择函数列的强大数定律
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作者 张丽娜 张瑶 《河北师范大学学报(自然科学版)》 CAS 2003年第3期235-238,共4页
设X_n,n≥0是在可数集I上取值的一列随机变量,f(X_0,X_1,…,X_n)是依赖X_0,X_1,…X_n的随机选择函数.利用分析方法讨论随机选择函数列的收敛性问题,得到了一些有关的强大数定律.
关键词 随机选择函数 强大数定律 随机变量 随机过程 收敛性
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并行散列选择算法
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作者 钟诚 《计算机工程与科学》 CSCD 2000年第3期32-35,共4页
基于散列方法、分组原理和弃大留小筛选原理 ,通过构造线性单调的散列函数 ,给出一种 ( m,n)选择问题的并行算法 ,并分析算法在具有 p个处理机的共享存储并行系统模型上实现的复杂性。理论分析和仿真实验结果表明 ,本算法是一种可伸缩... 基于散列方法、分组原理和弃大留小筛选原理 ,通过构造线性单调的散列函数 ,给出一种 ( m,n)选择问题的并行算法 ,并分析算法在具有 p个处理机的共享存储并行系统模型上实现的复杂性。理论分析和仿真实验结果表明 ,本算法是一种可伸缩、简明实用、快速的并行选择算法。 展开更多
关键词 并行散选择算法 算法复杂性 微机
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高速铁路引入枢纽信号系统优化设计 被引量:1
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作者 邓伟龙 《铁路通信信号工程技术》 2024年第1期16-20,35,共6页
高速铁路引入枢纽给信号系统设计带来挑战,结合京沈客专引入北京枢纽,从枢纽内列控等级选择、场联分界处自动触发、提高枢纽整体运行效率等方面提出优化方案,以期对其他类似工程建设起到借鉴、参考作用。
关键词 优化设计 枢纽 高速铁路 控等级选择 场联分界 自动触发 提高效率
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一种综合的二阶段无监督特征选择方法
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作者 吕靖 童若锋 《中国科技论文在线》 CAS 2011年第4期268-272,279,共6页
结合单词贡献度(TC)和列选择(CS),提出了一种综合的二阶段无监督特征选择方法。先利用TC方法快速去除对整体不具影响力的特征,再结合CS方法提出了一个对剩余特征选取特征子集的目标函数,并利用贪心和直推式实验设计的思想求解目标函数,... 结合单词贡献度(TC)和列选择(CS),提出了一种综合的二阶段无监督特征选择方法。先利用TC方法快速去除对整体不具影响力的特征,再结合CS方法提出了一个对剩余特征选取特征子集的目标函数,并利用贪心和直推式实验设计的思想求解目标函数,最终获得精简特征子集。实验结果表明,所提出的方法在只选取很少量的特征时,聚类效果比已有的方法更好。 展开更多
关键词 无监督学习 特征选择 单词贡献度 选择 文本聚类
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用VB.NET设计ASP.NET程序的典型实例 被引量:1
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作者 蒋铁海 《信息技术》 2004年第7期89-91,共3页
介绍了用VB.NET设计ASP.NET程序的二个典型实例,它们分别是选择列功能的实现和超级链接列功能的实现。这些实例在开发ASP.NET应用系统中很有实用价值。
关键词 VB.NET ASP.NET 数据库 分页显示 选择列 超级链接
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圆形零件的排样问题 被引量:1
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作者 刘毅 曹炬 凌少东 《锻压技术》 CAS CSCD 北大核心 2005年第5期33-35,共3页
根据某家电制造企业提出的圆形零件排样问题,给出了该企业提供的3种排样方式———并排、品排和品排斜排的模型。然后,对这3种排样方式进行了简单的介绍和分析,并通过对实际数据的计算说明了品排斜排的排样方式要优于并排的排样方式。... 根据某家电制造企业提出的圆形零件排样问题,给出了该企业提供的3种排样方式———并排、品排和品排斜排的模型。然后,对这3种排样方式进行了简单的介绍和分析,并通过对实际数据的计算说明了品排斜排的排样方式要优于并排的排样方式。针对品排斜排的排样方式,又提出多列选择,即在原始的品排斜排方案上去掉“两列一组”的限制,改为多列一组,并利用实验数据,给出品排斜排下各列对应的利用率。通过这些利用率数据发现:品排斜排方式下的利用率随列数的增加呈现一个先升后降的趋势。 展开更多
关键词 圆形零件的排样 并排 品排 品排斜排 选择
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平台式FPGA中可重构存储器模块的设计 被引量:2
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作者 段会福 于芳 +1 位作者 陈陵都 刘忠立 《微计算机信息》 北大核心 2008年第2期191-193,共3页
可重构静态存储器(SRAM)模块是场可编程门阵列(FPGA)的重要组成部分,它必须尽量满足用户不同的需要,所以要有良好的可重构性能。本文设计了一款深亚微米工艺下的16-kb的高速,低功耗双端口可重构SRAM。它可以重构成16Kx1,8Kx2,4Kx4,2Kx8,... 可重构静态存储器(SRAM)模块是场可编程门阵列(FPGA)的重要组成部分,它必须尽量满足用户不同的需要,所以要有良好的可重构性能。本文设计了一款深亚微米工艺下的16-kb的高速,低功耗双端口可重构SRAM。它可以重构成16Kx1,8Kx2,4Kx4,2Kx8,1Kx16和512x32六种不同的工作模式。基于不同的配置选择,此SRAM可以配置为双端口SRAM,单端口SRAM,ROM,FIFO,大的查找表或移位寄存器,本文完整介绍了该SRAM的设计方法,重点介绍了一种新颖的存储单元电路结构:三端口存储单元,以及用于实现可重构功能的电路的设计方法。 展开更多
关键词 静态存储器 可重构 三端口存储单元 选择 灵敏放大器
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Control of reactive dividing wall column for selective hydrogenation and separation of C3 stream 被引量:5
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作者 Xing Qian Shengkun Jia +2 位作者 Yiqing Luo Xigang Yuan Kuo-Tsong Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1213-1228,共16页
In our previous work, the reactive dividing wall column(RDWC) was proposed and proved to be effective for selective hydrogenation and separation of C3 stream. In the present paper, the dynamics and control of the prop... In our previous work, the reactive dividing wall column(RDWC) was proposed and proved to be effective for selective hydrogenation and separation of C3 stream. In the present paper, the dynamics and control of the proposed RDWC are investigated. Four control structures including composition and temperature controls are proposed. The feed forward controllers are employed in the four control strategies to shorten the dynamic response time, reduce the maximum deviations and offer an immediate adjustment. The control structures are compared by applying them into the RDWC system with 20% disturbances in both the feed flow rate and the feed compositions, and the results are discussed. 展开更多
关键词 Process control C3 stream selective hydrogenation Reactive dividing wall column
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A Strong Limit Theorem on Generalized Random Selection for m-valued Random Sequences
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作者 汪忠志 徐付霞 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第4期343-348,共6页
In this paper, a strong limit theorem on gambling strategy for binary Bernoulli sequence, (i.e.) irregularity theorem, is extended to random selection for dependent m-valued random variables, via using a new method-di... In this paper, a strong limit theorem on gambling strategy for binary Bernoulli sequence, (i.e.) irregularity theorem, is extended to random selection for dependent m-valued random variables, via using a new method-differentiability on net. Furthermore, by allowing the selection function to take value in finite interval [-M,M], the conception of random selection is generalized. 展开更多
关键词 generalized random selection differentiability on net a.e.convergence
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BLIND CHANNEL ESTIMATION IN DELAY DIVERSITY FOR FREQUENCY SELECTIVE CHANNELS
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作者 ZhaoZheng JiaYing YinQinye 《Journal of Electronics(China)》 2003年第5期326-336,共11页
Delay diversity is an effective transmit diversity technique to combat adverse effects of fading. Thus far, previous work in delay diversity assumed that perfect estimates of current channel fading conditions are ava... Delay diversity is an effective transmit diversity technique to combat adverse effects of fading. Thus far, previous work in delay diversity assumed that perfect estimates of current channel fading conditions are available at the receiver and training symbols are required to estimate the channel from the transmitter to the receiver. However, increasing the number of the antennas increases the required training interval and reduces the available time with in whichdata may be transmitted. Learning the channel coefficients becomes increasingly difficult for the frequency selective channels. In this paper, with the subspace method and the delay character of delay diversity, a channel estimation method is proposed, which does not use training symbols. It addresses the transmit diversity for a frequency selective channel from a single carrier perspective in the form of a simple equivalent flat fading model. Monte Carlo simulations give the performance of channel estimation and the performance comparison of our channel-estimation-based detector with decision feedback equalization, which uses the perfect channel information. 展开更多
关键词 Delay diversity Subspace method Blind channel estimation Frequency selective channels Array signal processing
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巧选纵向Word文本
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作者 西贝 《电脑校园》 2002年第11期35-35,共1页
关键词 WORD 文本选择 纵向选择 方法
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上市公司互联网投资者关系管理存在印象管理行为吗 被引量:1
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作者 林琳 潘琰 《当代财经》 CSSCI 北大核心 2015年第5期119-128,共10页
以2013年十大黑榜上市公司为样本进行选择性列报分析,并以中国百强上市公司为样本对其网站发布的董事长报告书及业绩新闻稿进行基于关键词的主题分析和基于陈述的主题分析。研究结果表明:上市公司互联网投资者关系管理存在以选择性列报... 以2013年十大黑榜上市公司为样本进行选择性列报分析,并以中国百强上市公司为样本对其网站发布的董事长报告书及业绩新闻稿进行基于关键词的主题分析和基于陈述的主题分析。研究结果表明:上市公司互联网投资者关系管理存在以选择性列报和强烈的正面主题偏向为特征的印象管理行为,可能对投资者造成误导,有必要将其纳入监管范围并尝试设计新型的监管机制,适当引导和强化监管并举,为保护投资者权益和促进我国资本市场持续健康发展提供应有保障。 展开更多
关键词 互联网 投资者关系管理 印象管理 选择 主题偏向
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Evolution of quasispecies diversity for porcine reproductive and respiratory syndrome virus under antibody selective pressure 被引量:4
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作者 ZHAO Peng MA ChengTai +1 位作者 DONG Xuan CUI ZhiZhong 《Science China(Life Sciences)》 SCIE CAS 2012年第9期788-792,共5页
To study the quasispecies diversity of porcine reproductive and respiratory syndrome virus (PRRSV), open reading frame 5 (ORF5) of strain SD0612 was amplified and cloned. Sixty clones of ORF5 were sequenced and analyz... To study the quasispecies diversity of porcine reproductive and respiratory syndrome virus (PRRSV), open reading frame 5 (ORF5) of strain SD0612 was amplified and cloned. Sixty clones of ORF5 were sequenced and analyzed with DNAStar software. Nucleic acid sequence homology was 97.7%-100%, with 78 mutations observed. Among these 60 clones, the sequences of 17 clones were identical and recognized as the dominant quasispecies of strain SD0612. Evolution of SD0612 quasispecies diversity under antibody selective pressure was also studied. SD0612 was passed continuously in the Marc-145 cell line over 40 passages in 6 independent lineages. SD0612 antiserum was not added to lineage A, B, and C cultures; however, antiserum was added to culture medium for lineages D, E, and F. PRRSV ORF5 was then amplified, cloned, and sequenced from each of the 6 lineages, designated as A40-F40. F40 was further passed in Marc-145 cells using 6 independent lineages with or without F40 antiserum for another 40 passages. ORF5 from the 6 newly-derived virus lineages, which we designated as a40-f40, were amplified, cloned and sequenced. The proportion of dominant quasispecies increased with passage number in cell cultures supplemented with antibodies, but decreased when antibodies were lacking. Our work has demonstrated a diversity of quasispecies for ORF5 in PRRSV SD0612. Antibody selective pressure was able to significantly influence quasispecies diversity and promote a dominant quasispecies that was able to evade immune reactions. 展开更多
关键词 porcine reproductive and respiratory syndrome virus (PRRSV) antibody selective pressure quasispecies diversity ORF5 ORF6
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TIME SERIES FORECASTING WITH MULTIPLE CANDIDATE MODELS:SELECTING OR COMBINING? 被引量:5
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作者 YULean WANGShouyang +1 位作者 K.K.Lai Y.Nakamori 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2005年第1期1-18,共18页
Various mathematical models have been commonly used in time series analysis and forecasting. In these processes, academic researchers and business practitioners often come up against two important problems. One is whe... Various mathematical models have been commonly used in time series analysis and forecasting. In these processes, academic researchers and business practitioners often come up against two important problems. One is whether to select an appropriate modeling approach for prediction purposes or to combine these different individual approaches into a single forecast for the different/dissimilar modeling approaches. Another is whether to select the best candidate model for forecasting or to mix the various candidate models with different parameters into a new forecast for the same/similar modeling approaches. In this study, we propose a set of computational procedures to solve the above two issues via two judgmental criteria. Meanwhile, in view of the problems presented in the literature, a novel modeling technique is also proposed to overcome the drawbacks of existing combined forecasting methods. To verify the efficiency and reliability of the proposed procedure and modeling technique, the simulations and real data examples are conducted in this study.The results obtained reveal that the proposed procedure and modeling technique can be used as a feasible solution for time series forecasting with multiple candidate models. 展开更多
关键词 time series forecasting model selection STABILITY ROBUSTNESS combiningforecasts
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A Note on a Provable Secure Encryption Scheme
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作者 王明强 秦静 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第6期655-658,共4页
A Cramer-Shoup scheme was modified in a variant way. The major advantage with respect to Kurosawa-Desmedt scheme is that it saves a key parameter and produces shorter ciphertext. The proof of security shows that our s... A Cramer-Shoup scheme was modified in a variant way. The major advantage with respect to Kurosawa-Desmedt scheme is that it saves a key parameter and produces shorter ciphertext. The proof of security shows that our scheme can be instantiated with any computational secure key derivation and message authentication functions. Thus it extends the applicability of the Kurosawa-Desmedt scheme and improves its efficiency. 展开更多
关键词 hybrid encryption scheme chosen-ciphertext attack authentication function
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