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121.
Epilepsy is among the most common brain disorders. Approximately 25–30% of epilepsy patients remain unresponsive to anti-epileptic drug treatment, which is the standard therapy for epilepsy. In this study, we apply optimization-based data mining techniques to classify the brain's normal and epilepsy activity using intracranial electroencephalogram (EEG), which is a tool for evaluating the physiological state of the brain. A statistical cross validation and support vector machines were implemented to classify the brain's normal and abnormal activities. The results of this study indicate that it may be possible to design and develop efficient seizure warning algorithms for diagnostic and therapeutic purposes. Research was partially supported by the Rutgers Research Council grant-202018, the NSF grants DBI-980821, CCF-0546574, IIS-0611998, and NIH grant R01-NS-39687-01A1.  相似文献   
122.
采用蒙特卡罗模型AMPT 究了(S_(NN))~(1/2)=130GeV Au Au碰撞中部分子相互作用对两粒子横向动量关联的影响,结果表明部分子相互作用对两粒子的横向动量关联有重要的贡献.还计算了AMPT模型中(S_(NN))~(1/2)=130GeV Au Au碰撞的两粒子横向动量关联与碰撞对心性的依赖关系并与来自STAR的实验数据进行了比较,发现AMPT的理论预言很好地符合实验数据.  相似文献   
123.
王晓  琚新军 《应用光学》1995,16(4):34-36
叙述一种新的光电复合测量技术,它集CCD摄像显示,微机信息采集与处理,光不投影放大,显微镜目视判读为一体,可对微粒大小及其空间分布实行多通道测量,观察和分析。  相似文献   
124.
Extensive Monte Carlo simulations of theant-in-the-labyrinth problem on randomL* L* L simple cubic lattices are performed, forL up to 960 on a CRAY-YMP supercomputer. The exponentk for the rms displacementr witht inrt k is found to bek=0.190±0.003. As a second approach, large percolation clusters with chemical shells up to 300 are generated on a simple cubic lattice at criticality. The diffusion equation is then solved by using the exact enumeration technique. The corresponding critical exponentd w is found to be 1/d w =0.250±0.003.On leave from I. Institut für Theoretische für Physik, Universität Hamburg, D-2000 Hamburg, Federal Republic of Germany.  相似文献   
125.
Optimality for set functions with values in ordered vector spaces   总被引:3,自引:0,他引:3  
Let (X, , ) be a finite atomless measure space,L a convex subfamily of , andY andZ locally convex Hausdorff topological vector spaces which are ordered by the conesC andD, respectively. LetF:LY beC-convex andG:LZ beD-convex set functions. Consider the following optimization problem (P): minimizeF(), subject to L andG() D . The paper generalizes the Moreau-Rockafellar theorem with set functions. By applying this theorem, a Kuhn-Tucker type optimality condition and a Fritz John type optimality condition for problem (P) are established. The duality theorem for problem (P) is also studied.This work was partially supported by National Science Council, Taipei, Taiwan. This paper was written while the first author was visiting at the University of Iowa, 1987-88.The authors would like to express their gratitude to the two anonymous referees for their valuable comments. Also, they would like to thank Professor P. L. Yu for his encouragement and suggestions which improved the material presented here considerably.  相似文献   
126.
Consider a sequenceF 1,F 2,... of i.i.d. random transformations from a countable setV toV. Such a sequence describes a discrete-time stochastic flow onV, in which the position at timen of a particle that started at sitex isM n(x), whereM n =F n F n–1 F 1. We give conditions on the law ofF 1 for the sequence (M n) to be tight, and describe the possible limiting law. an example called the block charge model is introduced. The results can be formulated as a statement about the convergence in distribution of products of infinite-dimensional random stochastic matrices. In practical terms, they describe the possible equilibria for random motions of systems of particles on a countable set, without births or deaths, where each site may be occupied by any number of particles, and all particles at a particular site move together.  相似文献   
127.
We consider a system of spins which have values ±1 and evolve according to a jump Markov process whose generator is the sum of two generators, one describing a spin-flipGlauber process, the other aKawasaki (stirring) evolution. It was proven elsewhere that if the Kawasaki dynamics is speeded up by a factor –2, then, in the limit 0 (continuum limit), propagation of chaos holds and the local magnetization solves a reaction-diffusion equation. We choose the parameters of the Glauber interaction so that the potential of the reaction term in the reaction-diffusion equation is a double-well potential with quartic maximum at the origin. We assume further that for each the system is in a finite interval ofZ with –1 sites and periodic boundary conditions. We specify the initial measure as the product measure with 0 spin average, thus obtaining, in the continuum limit, a constant magnetic profile equal to 0, which is a stationary unstable solution to the reaction-diffusion equation. We prove that at times of the order –1/2 propagation of chaos does not hold any more and, in the limit as 0, the state becomes a nontrivial superposition of Bernoulli measures with parameters corresponding to the minima of the reaction potential. The coefficients of such a superposition depend on time (on the scale –1/2) and at large times (on this scale) the coefficient of the term corresponding to the initial magnetization vanishes (transient bimodality). This differs from what was observed by De Masi, Presutti, and Vares, who considered a reaction potential with quadratic maximum and no bimodal effect was seen, as predicted by Broggi, Lugiato, and Colombo.  相似文献   
128.
采用两种方法制得了尖晶石结构纯相MgFe2O4样品.Moessbauer分析发现,一种样品表现出了完全的超顺磁性,另一种表现出了部分超顺磁性.这揭示出了样品具有很小的粒子尺度.首次在实验上发现了MgFe2O4IR-V2谱带的劈裂现象,报导了拉曼光谱,通过ESR分析,进一步揭示了两样品的结构特征,并讨论了性质之间的相关性。  相似文献   
129.
氢氧化铝镁正电溶胶制备及性能研究   总被引:27,自引:3,他引:27  
氢氧化铝镁正电溶胶制备及性能研究侯万国,张春光,孙德军,梁晓丽,王果庭(山东大学胶体与界面化学研究所,济南,250100)关键词混合金属氢氧化物,溶胶,超细颗粒混合金属氢氧化物的合成、组成及结构等已得到广泛研究[1,2].我们也曾用插入法合成了混合金...  相似文献   
130.
纳米碳酸锌的制备和热分解动力学参数的测定   总被引:3,自引:0,他引:3  
Nanosized zinc carbonate was prepared in the droplet of nano-reactor based on microemusion. The influences of the concentration of the surfactant and reactant on the diameter of nanoparticles were studied and the kinetic pa-rameters of thermal decomposition reaction were determined. It can be shown from experimental results, the di-ameter of the droplet in the microemulsion which have dissolved reactant zinc nitrate and sal volatile is between 4.9nm and 7.7nm, 6.2nm and 12.4nm, respectively. Nanosized zinc carbonate prepared by the method of mi-croemusion has shown good dispersion, narrow distribution and light agglomeration. The particle size of nanosized zinc carbonate is between 5nm and 40nm, and its kinetic parameters of thermal decomposition reaction-activation energy E and reaction order n are 110kJ·mol-1 and 0.9, respectively.  相似文献   
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