基于动态规划的水电站机组间负荷分配程序开发

水电站机组间负荷分配计算中的阶段变量与状态变量的个数越多,计算量就越大,且计算程序也越复杂,因而仅用手工计算很难做到。为此,利用动态规划法建立了水电站厂内经济运行流量分配数学模型。使用编程软件Visual Basic开发了水电站机组间负荷分配程序;该程序界面友好,使用方便,且能大大提高计算速度。应用该程序,对水电站机组间的负荷分配进行了实际应用计算,得出了经济效益最优的负荷分配方案。     

Video events recognition by improved stochastic parsing based on extended stochastic context-free grammar representation

Video events recognition is a challenging task for high-level understanding of video sequence. At present,there are two major limitations in existing methods for events recognition. One is that no algorithms are available to recognize events which happen alternately. The other is that the temporal relationship between atomic actions is not fully utilized. Aiming at these problems,an algorithm based on an extended stochastic contextfree grammar ( SCFG) representation is proposed for events recognition. Events are modeled by a series of atomic actions and represented by an extended SCFG. The extended SCFG can express the hierarchical structure of the events and the temporal relationship between the atomic actions. In comparison with previous work,the main contributions of this paper are as follows: ① Events ( include alternating events) can be recognized by an improved stochastic parsing and shortest path finding algorithm. ② The algorithm can disambiguate the detection results of atomic actions by event context. Experimental results show that the proposed algorithm can recognize events accurately and most atomic action detection errors can be corrected simultaneously.     

Research on Comparison and Evaluation Studies of Several Smoothing Denoising Method Based on γ-ray Spectrum Detector

The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI(TI)[JP] gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM(Peak High/Full Width at Half Maximum) and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex γ-spectrum on Embedded system platform, and the statistical fluctuation of γ-spectrum is filtered well.     

CAD/CAM在钣金放样展开及下料方面的应用

介绍了以三维Solidworks软件为设计平台,对裤型椭圆锥三通管进行放样和展开,生成的二维图形经过排料后直接输出给数控编程软件FastCAM,并生成火焰切割机的加工程序,火焰切割机直接进行切割的实现方法.     

泊松过程在用户上下线模型中的应用

提出了基于非齐次泊松过程的宽带拨号上网(ADSL)用户上下线模型.对用户上下线行为进行建模,并基于现网真实数据,使用模型计算用户24 h内的每时刻退出登录的平均概率,将模型的预测值与现网实测数据进行对比,分析了不同用户组退出登录概率一天内的变化和持续在线平均概率的变化.分析结果表明,提出的ADSL宽带用户上下线模型可以有效、量化地描述用户上下线行为,在ADSL宽带用户上下线行为的异常检测和舆情分析等领域具有较好的工程应用价值.     

求解上层含约束条件的模糊二层多随从线性规划的结构元方法

讨论了一类上层含约束条件的模糊二层多随从线性规划模型;利用结构元理论,证明了该模型的最优解等价于上层含约束条件的二层多随从线性规划模型最优解;并通过极点搜索法,得到了该模型最优解;最后通过数值算例验证了该方法的可行性。     

在红利支付情形下考虑负效用的消费投资问题

研究了经济代理人面临红利支付和劳动负效用情形下投资与退休选择问题,其中考虑了风险资产派发红利及劳动会给经济代理人带来效用损失的情形.代理人享有退休选择权,退休决策使得代理人避免了劳动负效用,却必须要放弃工资收入.代理人效用来自消费,并且受劳动负效用的直接影响.利用动态规划的方法去解自由边值问题,得到了代理人临界财富水平和最优消费投资组合策略显示解.     

Stochastic formulation of particle kinetics in wall-bounded two-phase flows

This paper presents a generalized framework of stochastic modeling for particle kinetics in wall-bounded flow. We modified a reflected Brownian motion process and straightforwardly obtained a Kramers equation for particle probability density function (PDF). After the wall effects were accounted for as a drift from zero in the mean displacement and suppression in the diffusivity of a particle, an analytical solution was worked out for PDF. Three distinguishable mechanisms were identified to affect the profile of particle probability distribution: external forces, turbophoresis effect, and wall-drift effect. The proposed formulation covers the Huang et al. (2009) model of a wall that produces electrostatic repulsion force and van der Waals force, as well as Monte-Carlo solutions for the Peter and Barenbrug (2002) model under a variety of relaxation times. Moreover, it successfully reproduces the two patterns of particle concentration profiles observed in experiments of sediment-laden open-channel flows. The strength of the wall-drift effect was found to be connected with the interaction frequency between particle and wall. Further exploration of the relationship among flow turbulence, particle inertia, and particle concentration is worthwhile.     

Development of 2D computer program to determine geometry of rock mass blocks简

Due to various geological processes such as tectonic activities fractures might be created in rock mass body which causes creation of blocks with different shapes and sizes in the rock body. Exact understanding of these blocks geometry is an essential issue concerned in different domains of rock engineering such as support system of underground spaces built in jointed rock masses, design of blasting pattern, optimization of fragmentation, determination of cube blocks in quarry mines, blocks stability, etc. The aim of this paper is to develop a computer program to determine geometry of rock mass blocks in two dimensional spaces. In this article, the geometry of jointed rock mass is programmed in MATLAB™.