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921.
陶蓉 《重庆文理学院学报(自然科学版)》2007,26(6):93-95
采用文献法、调查访问法分析在我国高校体育院系开设舞龙运动项目的意义,探讨项目开发具有的优势,结果表明:高校体育院系能担负起舞龙运动实现现代化的使命. 相似文献
922.
基于细胞图像的肺癌诊断系统主要是利用数字图像处理和模式识别的技术对肺癌细胞的图像处理,并根据提取出的细胞特征对肺癌进行早期的病理诊断.不同于以往的细胞诊断系统,文中提出了新的细胞分割和重叠细胞重构的方法.首先把彩色肺癌细胞图像转化为灰度图像,对其进行平滑、去噪,然后用一种新的基于强化学习的方法寻找合适的灰度阈值,把细胞区域分割出来,形成二值图像,并对图像进行基于形态学的二值滤波,再针对此时分割出的重叠细胞,利用一种改进的deBoor—Cox方法分离与重构,最后进行特征提取,根据提取出来的多种特征对细胞分类,诊断出肺癌细胞. 相似文献
923.
To efficiently use the array aperture and avoid the complicated parameter pairing computation,this paper proposes a new cumulant-based algorithm for localizing near-field narrowband sources.Firstly,this algorithm proposes a symmetric uniform linear ar- ray (ULA),and constructs three cumulant matrices by using the fourth-order cumulants of some properly chosen sensor outputs;second- ly,unlike the conventional parallel factor (PARAFAC) analysis models in data or subspace domain,it forms a three-way array (TWA) in the fourth-order cumulant domain using the three matrices,and analyzes the uniqueness of its low-rank decomposition;thirdly,it jointly estimates the frequency,the direction-of-arrival (DOA),and the range of each near-field source from the matrices via the low-rank de- composition of the TWA.The simulation results are presented to validate the performance of our proposed method. 相似文献
924.
P systems based multi-objective optimization algorithm 总被引:2,自引:0,他引:2
Based on P systems, this paper proposes a new multi-objective optimization algorithm (PMOA). Similar to P systems, PMOA has a cell-like structure. The structure is dynamic and its membranes merge and divide at different stages. The key rule of a membrane is the communication rule which is derived from P systems. Mutation rules are important for the algorithm, which has different ranges of mutation in different membranes. The cooperation of the two rules contributes to the diversity of the population, the conquest of the muhimodality of objective function and the convergence of algorithm. Moreover, the unique structure divides the whole population into several sub populations, which decreases the computational complexity. Almost a dozen popular algorithms are compared using several test problems. Simulation results illustrate that the PMOA has the best performance. Its solutions are closer to the true Pareto-optimal front 相似文献
925.
在移动计算环境中,断连后,移动客户机根据缓存的数据在本地执行事务,重新连接后,移动客户机中的事务作为暂态事务提交给固定主机重新执行.如果移动客户机与固定主机的读/写、写/写冲突机率很高,则暂态事务在固定主机上成功提交的概率就很低,大量的暂态事务就会夭折,这将浪费大量的服务器资源和通信资源,从而降低整个系统的性能.为了提高暂态事务重提交的成功概率,本文提出按概率提交暂态事务的方法.该方法在冲突频率非常高的场合,能够节省移动客户机的传送开销,减轻固定主机的负担,提高事务的吞吐量. 相似文献
926.
You-Cheng Zhang Ying-hong Liang 《科技信息》2007,(35)
数据挖掘是计算机行业中发展最快的领域之一,它使数据库技术进入了一个更高级的阶段,已经迅速扩大成为一个独立的领域。本文指出了数据挖掘与数据库知识发现过程中的关系。总结了数据挖掘实现所面临问题及其任务,最后介绍了数据挖掘的实际应用。 相似文献
927.
~4.1 Ga xenocrystal zircon from Ordovician volcanic rocks in western part of North Qinlin80rosenic Belt 总被引:4,自引:0,他引:4
WANG HongLiang CHEN Liang SUN Yong LIU XiaoMing xu XueYi CHEN JuanLu ZHANG Hong DIWU ChunRong 《科学通报(英文版)》2007,52(21):3002-3010
High-precision U-Pb dating by in situ LA-ICP-MS yields an age of 4079±5 Ma for a xenocrystal zircon from Ordovician volcanics of the Caotangou Group in western part of the North Qinling Orogenic Belt. As a result, the North Qinling Orogenic Belt becomes one of a few localities in the world that contain Hadean age records (4276±6 Ma and 4404±8 Ma detrital zircons from Jack Hill of the Yilgarn craton, 4016 Ma Acasta gneisses of the Wopmay Orogeny and Burang quartzite with detrital zircon of 4103 Ma in Tibet). It is also the first report of the Hadean age in Phanerozoic volcanics. The finding of the 4.1 Ga xenocrystal zircon provides not only the geochronological record of the oldest crustal materials in China, but also the condition for further search for rocks forming in the region during the early time of the Earth's evolution. Thirty-six zircon U-Pb dates from the Ordovician volcanic rocks are subgrouped into seven generations that represent different tectono-magmatic events in the North Qinling Orogenic Belt. Among them, two periods of 0.9--1.5 Ga and 0.4--0.5 Ga are consistent with Mesoproterozoic and Early Paleozoic orogenies, respectively. 相似文献
928.
A tubular focused sonochemistry reactor 总被引:1,自引:0,他引:1
ZHOU GuangPing LIANG ZhaoFeng LI ZhengZhong ZHANG YiHui 《科学通报(英文版)》2007,52(14):1902-1905
This paper presents a new sonochemistry reactor, which consists of a cylindrical tube with a certain length and piezoelectric transducers at tube’s end with the longitudinal vibration. The tube can effectively transform the longitudinal vibration into the radial vibration and thereby generates ultrasound. Furthermore, ultrasound can be focused to form high-intensity ultrasonic field inside tube. The reactor boasts of simple structure and its whole vessel wall can radiate ultrasound so that the electroacoustic transfer efficiency is high. The focused ultrasonic field provides good condition for sonochemical reaction. The length of the reactor can be up to 2 meters, and liquids can pass through it continuously, so it can be widely applied in liquid processing such as sonochemistry. 相似文献
929.
Determining method and conditional factors of electrochemical fingerprint of Chinese traditional medicine 总被引:4,自引:1,他引:4
ZHANG TaiMingt LIANG YiZeng YUAN Bin DING Feng ZHANG YaPeng WEI ManQiong CHEN Xu 《科学通报(英文版)》2007,52(16):2190-2202
The thermodynamic systems and kinetic model suitable for the electrochemical token of the compo-nent throng in Chinese traditional medicines have been analyzed. It has been indicated that the damp oscillatory reactions in the non-equilibrium close system and open system without the supplement of dissipative substance have important significance for the throng token and analysis of chemical com-ponents in Chinese traditional medicines. Various factors influencing the electrochemical fingerprint,such as reactant species and their concentrations,electrode types,temperature,stir rate,the kind,dosage and granularity of Chinese traditional medicines,have amply been researched by the B-Z os-cillatory reaction which used malonic acid as a main dissipative substance. In addition,the quantitative information about the chemical components in Chinese traditional medicines has been discussed in detail. The method and its conditions for determining the electrochemical fingerprint used in scientifi-cally distinguishing and evaluating Chinese traditional medicines have successfully been put forward. 相似文献
930.
武亮 《中山大学研究生学刊(自然科学与医学版)》2007,28(2):74-82
利用NCEP/NCAR的在分析资料,分析了1948~2004年期间澳大利亚(以下简称澳高)的年变化和日变化及其对南海夏季风的影响。结果显示在澳高强弱年这种影响有着不同的结果:在年际变化中,澳高与南海夏季风的相关性在澳高弱年明显大于强澳高年;而日变化中,澳高与南海夏季风的相关性在澳高弱年为正,澳高强年则为负。进一步研究表明,造成这些现象的原因大致可以归为:强弱澳高年,越赤道气流的通道变换;西太平洋副热带高压(以下简称副高)的位置偏向;马斯可林高压(以下简称马高)的作用的叠加效应.这些作用对于南海夏季风的重要组成部分:越赤道气流产生了重要影响,从而影响了南海夏季风的强度。 相似文献