Research on the Bit Computation Model for Time Variable Channel Bandwidth

For the encoding bit-rate problem in H.264 wireless video communication,this paper analyzes the bit-rate computation model and the Mean Square Error distortion model,establishes the relation between the quantization parameter of the encoding bit-rate and the intra frame refresh rate of the macro block,and put forward a new ideal about the coding rate on the basis of general binomial computation model theory. Furthermore,this method not only can adaptively adjust the bit allocation and quantization parameter and prevents buffer from overflowing downward or upward under given network bandwidth,but also can apply the rate-distortion to optimize the solution method,control the encoding bits accurately and optimizes the allocation between the intra and inter frame encoding macro block.     

Stability Analysis of Stochastic Swarm Systems

In this paper,we present a model of stochastic swarm system and prove the stability of this kind of systems. We establish the stable aggregating behavior for the group using a coordination control scheme. This individual-based control scheme is a combination of attractive and repulsive interactions among the individuals in the group,which ensures the cohesion of the group and collision avoidance among the individuals. The dynamics of each individual depends on the relative positions between the individuals and the influences of the random disturbances. Under the influences of the noises,this position-based control strategy still generates the stable aggregating behavior harmoniously for the group and the self-organized swarm pattern is formed.     

Analysis of Conditional Value-at-Risk for Newsvendor with Holding and Backorder Cost under Market Search

We consider a distribution system with one supplier and two retailers. For the two retailers, they face different demand and are both risk averse. We study a single period model which the supplier has ample goods and the retailers order goods separately. Market search is measured as the fraction of customers who unsatisfied with their ＂local＂ retailer due to stock-out, and search for the goods at the other retailer before leaving the system. We investigate how the retailers game for order quantity in a Conditional Value-at-Risk framework and study how risk averse degree, market search level, holding cost and backorder cost influence the optimal order strategies. Furthermore, we use uniform distribution to illustrate these results and obtain Nash equilibrium of order strategies.     

Rough Sets and Nuclear Safety

It is well-known that rough set theory can be applied successfully to rough classification and knowledge discovery. Our work is concerned with finding methods for using rough sets to identify classes in datasets, finding dependencies in relations and discovering rules which are hidden in databases by means of decision tables and algorithm D. We use these methods to analyze and control aspects of nuclear energy generation.     

Density functional theory study on the insertion reaction mechanism of dibromocarbene with formaldehyde

The insertion reaction mechanism of CBr2 with CH3CH2O has been studied by using the B3LYP/6-311G(d) and CCSD(T)/6-311G(d) at single point. The geometries of reactions,transition state and products were completely optimized. All the transition state is verified by the vibrational analysis and the internal re-action coordinate (IRC) calculations. The results show that reaction (1) is the dominant reaction path,which proceeds via two steps: i) two reactants form an intermediate (IM1),which is an exothermal re-action of 8.62 kJ·mol?1 without energy barrier; ii) P1 is obtained via the TS1 and the H-shift,in which the energy barrier is 44.53 kJ·mol?1. The statistical thermodynamics and Eyring transition state theory with Wigner correction are used to study the thermodynamic and kinetic characters of this reaction in temperature range from 100 to 2200 K. The results show that the appropriate reaction temperature ranges from 200 to 1900 K at 1.0 atm,in which the reaction has a bigger spontaneity capability,equi-librium constant (K) and higher rate constant (k).     

靶体响应力函数的确定方法及其在侵彻力学中的应用

首先,介绍了力函数的确定方法包括经验法、理论分析法和数值模拟法.其中经验法中给出了Forrestal半经验公式和改进的Wen半经验公式;理论分析法中详细介绍了空穴膨胀理论及其研究进展;数值模拟方法中模拟了半无限大材料中的球形和柱形空穴膨胀模型,并将模拟得到的结果与理论解进行了比较,发现二者吻合得很好.最后,给出了靶体响应力函数在侵彻力学中的应用.     

光致聚合材料收缩对谱面全息存储的影响

为了分析光致聚合材料记录的谱面全息图在再现过程中发生"擦除"现象,将谱面全息图看作由不同角谱的物光与参考光在光致聚合材料内形成的不同倾斜角度的光栅总和.使用二波耦合理论分析全息图像再现时,由于光致聚合材料发生形体收缩,不同倾斜程度的光栅发生不同程度的变形,产生不同程度的布拉格失配带来的衍射效率变化.理论分析表明,材料收缩越严重,全息图再现质量越差.实验证明了理论分析的正确性,并表明使用无收缩光致聚合材料可以消除这种"擦除"现象.     

瓦斯爆炸的脆性理论层次分析

针对导致煤矿瓦斯爆炸事故发生的各种致因,运用脆性理论和模糊层次分析法对其进行脆性分析.从事件级别上考虑瓦斯爆炸的脆性过程,分析瓦斯系统内部各个事件之间的脆性联系,从中找出使整个系统崩溃(事故发生)的因素集合,利用模糊层次分析法建立计算煤矿瓦斯爆炸事故中各种致因权重的层次分析模型.根据模型计算所得结果,确定了在瓦斯积聚产生的前提下,火源的4个主要致因权重的重要度排序,由大到小依次为:放炮、机电管理混乱、明火、撞击摩擦火花.对它们进行重点监控,可以很大程度地避免事故发生.该模型及其结果为控制和预防瓦斯爆炸提供了理论依据.     

传感器融合技术在火灾预警探测中的应用研究

针对传统火灾报警系统存在的局限性,本文把传感器融合技术应用到火灾预警探测系统中.该系统采用传感器组探测早期火灾特征,在进行数据处理时,首先对同质传感器进行自适应加权数据融合,再对同质传感器采用D-S证据理论进行全局融合,最后得出对火灾的最优判断,很好地解决了报警灵敏度和误报率之间的矛盾.系统采取模块化设计,结构简单,容易实现等.     

初等强度理论在计算空心圆杆剪应力时的应用

空心圆杆弯曲剪应力理论公式比较复杂,应用不便,本文对某些工程实际问题,按初等强度理论方法将问题予以简化,得出圆环内、外半径比b/a≥0.6时,在一定范围内可用初等理论公式代替弹性理论公式。