期刊文献+
共找到9篇文章
< 1 >
每页显示 20 50 100
PRAM和LARPBS模型上的近似串匹配并行算法 被引量:19
1
作者 钟诚 陈国良 《软件学报》 EI CSCD 北大核心 2004年第2期159-169,共11页
近似串匹配技术在网络信息搜索、数字图书馆、模式识别、文本挖掘、IP路由查找、网络入侵检测、生物信息学、音乐研究计算等领域具有广泛的应用.基于CREW-PRAM(parallel random access machine with concurrent read and exclusive wri... 近似串匹配技术在网络信息搜索、数字图书馆、模式识别、文本挖掘、IP路由查找、网络入侵检测、生物信息学、音乐研究计算等领域具有广泛的应用.基于CREW-PRAM(parallel random access machine with concurrent read and exclusive write)模型,采用波前式并行推进的方法直接计算编辑距离矩阵D,设计了一个允许k-差别的近似串匹配动态规划并行算法,该算法使用(m+1)个处理器,时间复杂度为O(n),算法理论上达到线性加速;采取水平和斜向双并行计算编辑距离矩阵D的方法,设计了一个使用a(m+1)个处理器和O(n/a+m)时间的、可伸缩的、允许k-差别的近似串匹配动态规划并行算法,+<11mna.基于分治策略,通过灵活拆分总线和合并子总线动态重构光总线系统,并充分利用光总线的消息播送技术和并行计算前缀和的方法,实现了汉明距离的并行计算,设计了两个基于LARPBS(linear arrays with reconfigurable pipelined bus system)模型的通信高效、可扩放的允许k-误配的近似串匹配并行算法,其中一个算法使用n个处理器,时间为O(m);另一个为常数时间算法,使用mn个处理器. 展开更多
关键词 近似串匹配 并行算法 CREW-PRAM(parallel random access machine with concurrent read and exclusive write) 可重构光总线系统 编辑距离 汉明距离
在线阅读 下载PDF
意识和无意识知觉:注意和刺激特性间的相互补偿 被引量:16
2
作者 耿海燕 朱滢 《心理学报》 CSSCI CSCD 北大核心 2001年第5期390-397,共8页
该研究基于Exclusion任务 ,利用质的差异的研究范式 ,不仅确立了意识和无意识知觉在行为结果上的质的差异 ,而且发现刺激特性和注意在决定知觉意识时存在相互补偿的现象。在实验一中 ,当靶字短暂呈现时 ,被试用靶字补笔的比率高于基线水... 该研究基于Exclusion任务 ,利用质的差异的研究范式 ,不仅确立了意识和无意识知觉在行为结果上的质的差异 ,而且发现刺激特性和注意在决定知觉意识时存在相互补偿的现象。在实验一中 ,当靶字短暂呈现时 ,被试用靶字补笔的比率高于基线水平 ;而当延长靶字呈现时间或提高对靶字的注意水平时 ,出现反转现象—用靶字补笔的比率低于基线水平。相对应地 ,在实验二中 ,分散注意条件下被试用靶字补笔的比率高于基线水平 ;而当注意集中或在分散注意条件下延长呈现时间时 ,出现了反转现象。 展开更多
关键词 Exclusion任务 意识 注意 刺激特性
在线阅读 下载PDF
离子排斥色谱法快速分析饮用矿泉水中的重碳酸盐 被引量:3
3
作者 刘京生 刘肖 +1 位作者 蔡亚岐 牟世芬 《色谱》 CAS CSCD 北大核心 2006年第6期661-661,共1页
关键词 离子排斥色谱法(ion EXCLUSION chromatography) 重碳酸盐(bicarbonate) 矿泉水(mineral water)
在线阅读 下载PDF
基于魔方旋转方法的量子彩色图像加密方案 被引量:1
4
作者 姜东焕 王华堃 徐光宝 《北京工业大学学报》 CAS CSCD 北大核心 2023年第6期656-666,共11页
为实现彩色图像安全高效加密,基于魔方旋转方法构建了一种量子图像置乱方案,并且设计出了对应的量子线路.结合量子异或(exclusive OR,XOR)操作和量子交换操作,实现了一种以量子魔方旋转图像置乱为基础的量子彩色图像加密方案,并对该加... 为实现彩色图像安全高效加密,基于魔方旋转方法构建了一种量子图像置乱方案,并且设计出了对应的量子线路.结合量子异或(exclusive OR,XOR)操作和量子交换操作,实现了一种以量子魔方旋转图像置乱为基础的量子彩色图像加密方案,并对该加密方案进行了全部量子线路设计与仿真实验,取得了良好的加密结果.该加密方案的算法复杂度相对于其经典算法有指数级加速. 展开更多
关键词 量子图像加密 魔方旋转 量子异或(exclusive OR XOR)操作 量子交换操作 量子门 位平面
在线阅读 下载PDF
基于色度分布差异性的唇部检测算法 被引量:6
5
作者 张志文 沈海斌 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2008年第8期1355-1359,共5页
为使唇读系统准确定位唇部图像,对彩色人脸图像的肤色和唇色进行了色度分布研究.利用直方图分析R、G、B色度分量在肤色和唇色中的分布特性,在此基础上提出了一种唇部检测算法.该算法同时考虑G、B分量以及R、G分量的分布差异,并将两种差... 为使唇读系统准确定位唇部图像,对彩色人脸图像的肤色和唇色进行了色度分布研究.利用直方图分析R、G、B色度分量在肤色和唇色中的分布特性,在此基础上提出了一种唇部检测算法.该算法同时考虑G、B分量以及R、G分量的分布差异,并将两种差异相互加强用于唇部判别.通过2组实验验证了算法效果.将提出的算法和Red Exclusion算法进行比较,结果表明,该方法在有效性、鲁棒性以及不同人种的肤色支持等方面有明显的改进. 展开更多
关键词 唇读 唇部检测 色度分布差异算法 RED Exclusion算法
在线阅读 下载PDF
Ad hoc distributed mutual exclusion algorithm based on token-asking 被引量:2
6
作者 Wang Zheng Liu Xin'song Li Mei'an 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期398-406,共9页
The solution of distributed mutual exclusion is difficult in Ad hoc networks owing to dynamic topologies and mobility. Based on the analysis of the properties of Ad hoc networks and the disadvantages of the traditiona... The solution of distributed mutual exclusion is difficult in Ad hoc networks owing to dynamic topologies and mobility. Based on the analysis of the properties of Ad hoc networks and the disadvantages of the traditional algorithms, an improved Ad hoc system model was given and a novel algorithm was presented as AHDME (Ad Hoc Distributed Mutual Exclusion); it was based on the token-asking algorithms. It utilized broadcast to search for the token and to decrease the message complexity of multi-hop Ad hoc networks. Lamport's timestamp was improved to ensure the time sequence and to prevent nodes from starvation. When compared to traditional algorithms, AHDME does not require the fixed size of request queues and the global system information, which adapts itself to the frequent arrival/departures and the limited computing capability of nodes in Ad hoc networks. Performance analysis and simulation results show that the AHDME algorithm has low message complexity, small space complexity, and short response delay. 展开更多
关键词 Ad hoc Distributed mutual exclusion Token-asking Logical timestamp.
在线阅读 下载PDF
Improved design of online fault diagnoser for partially observed Petri nets with generalized mutual exclusion constraints 被引量:2
7
作者 Jiufu Liu Wenliang Liu +2 位作者 Jianyong Zhou Yan Sun Zhisheng Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期971-978,共8页
This paper investigates the fault detection problem for discrete event systems (DESs) which can be modeled by partially observed Petri nets (POPNs). To overcome the problem of low diagnosability in the POPN online fau... This paper investigates the fault detection problem for discrete event systems (DESs) which can be modeled by partially observed Petri nets (POPNs). To overcome the problem of low diagnosability in the POPN online fault diagnoser in current use, an improved online fault diagnosis algorithm that integrates generalized mutual exclusion constraints (GMECs) and integer linear programming (ILP) is proposed. Assume that the POPN structure and its initial markings are known, and the faults are modeled as unobservable transitions. First, the event sequence is observed and recorded. GMEC is used for elementary diagnosis of the system behavior, then the ILP problem of POPN is solved for further diagnosis. Finally, an example of a real DES to test the new fault diagnoser is analyzed. The proposed algorithm increases the diagnosability of the DES remarkably, and the effectiveness of the new algorithm integrating GMEC and ILP is verified. 展开更多
关键词 fault diagnosis partially observed Petri nets (POPNs) integer linear programming (ILP) generalized mutual exclusion constraints (GMECs)
在线阅读 下载PDF
Local inhomogeneity in totally asymmetric simple exclusion processes with different hopping rates 被引量:1
8
作者 肖松 吴淑英 +1 位作者 郑东升 刘明哲 《Journal of Central South University》 SCIE EI CAS 2012年第10期3012-3016,共5页
Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A s... Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A simple approximate theory and extensive Monte Carlo computer simulations were used to calculate the steady-state phase diagrams and bulk densities. It is found that the phase diagram for local inhomogeneity in TASEP with different hopping rates p is qualitatively similar to homogeneous models. Interestingly, there is a saturation point pair (a*, fl*) for the system, which is decided by parameters p and q. There are three stationary phases in the system, when parameter p is fixed (i.e., p=0.8), with the increase of the parameter q, the region of LD/LD and HD/HD phase increases and the HD/LD is the only phase which the region shrinks. The analytical results are in good agreement with simulations. 展开更多
关键词 asymmetric simple exclusion process INHOMOGENEITY hopping rate Monte Carlo simulation approximate theory computer simulation
在线阅读 下载PDF
Construction ot retroviral vectors containing human multidrug resistance gene (mdr1) and their expression in NIH3T3 cells
9
作者 Sheng Zhou, Ning Mao, Lingya Pan, Ying Wu, Chunmei Hou, Yiqiang Wang, Pei-Hsien Tang Beijing Institute of Basic Medical Sciences, Beijing100850 《中国实验血液学杂志》 CAS CSCD 1997年第3期330-331,共2页
In order to increase the expression of mdrl genetransfectcd using retroviral vcctors, we constructedtwo retroviral vectors (LmdrlSN and MSCV-mdrl)containing mdrl cDNA and compared the expressionof mdrl gene with anoth... In order to increase the expression of mdrl genetransfectcd using retroviral vcctors, we constructedtwo retroviral vectors (LmdrlSN and MSCV-mdrl)containing mdrl cDNA and compared the expressionof mdrl gene with another vector pHamdrl/A(Pastan et al. Proc Natl Acad Sci USA 85: 4486,1986) in NIH.3T3 cells. The LmdrlSN was made 展开更多
关键词 POLYCLONAL HEMATOPOIETIC CASSETTE EXCLUSION excluded monoclonal packaging promoter RHODAMINE screened
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部