基于高速列车作用引起的铁道线路垂向动态响应的研究

研究了在高速列车作用下，由运行质量变化和沿线路方向的弹性基础支撑的非均匀性等所引起的对铁道线路的垂向动态响应。在时域内使用FEA法推导建立了高速列车／线路系统相互作用的运动方程，通过使用数值积分算法，分析了车辆运行速度、移动质量、线路的弹性基础支撑及其非均匀性等参数变化对铁道线路动态性能的影响，通过与通用分析模型结果进行的对比显示了良好的一致性。研究表明轨枕失效区域对钢轨的动态响应影响显著，在非均匀弹性基础支撑上钢轨的变形与移动质量的大小成反比，但在均匀基础支撑上钢轨的变形则与移动质量的大小无关。     

利用GPS-RIK技术进行既有线曲线整正测量研究

既有线曲线整正测量是铁路既有线提速改造和工务部门大修设计的主要任务之一。需要改造的既有铁路一般均为繁忙干线，并行车密度较高。传统的测量方法是将测量仪器安置在线路上，这样不仅在作业过程中受行车干扰，作业效率也不够高，而曲线地段通视条件差，作业难度是相当大的。同时，作业人员的安全问题也变得十分突出。笔者提出采用先进的GPS-RIK技术，对既有线曲线整正进行测量。采用该技术不仅能克服气候条件的限制，而且能以较高的频率，较高的精度测定互不通视的各被测点的坐标，克服了传统的作业方法要求置镜点与被测点之间必须通视、作业受天气影响、存在误差累积、内业计算工作量大等缺陷。该法在保证作业人员安全的前提下大大提高作业效率。     

城市边缘旅游新区的开发模式--以西安曲江新区为例

作为城市边缘的旅游新区开发,既是城市化发展的需要,也是提升区域旅游业竞争力的要求.开发旅游新区,整合区域旅游资源,打造旅游特色,已成为各个区域旅游业发展的必然选择.以西安曲江旅游新区的开发为例证,从新区功能定位、空间组织以及旅游特色塑造等方面阐释了城市新区的开发模式,即功能定位的"三维视角","主-次中心组团式"的空间组织模式以及旅游产品开发的"三优模式",可为其它城市边缘旅游新区的开发提供可资借鉴的典型案例.     

APPLICATION OF A SINGLE RESERVOIR OPERATION POLICY TO A RAIN WATER CISTERN SYSTEM1

The operation policy for a single reservoir is applied to a rain water cistern system because the functions of a cistern are similar to a simple single reservoir. Since the cistern is a closed system, water loss is negligible. In this study, a dynamic programming analysis has been made to study the effects of the probable weekly rainfall and the water storage in the cistern towards the water consumption policy. The result of this study indicates that the water consumption rate should be adjusted into a lower rate when the water storage in the cistern is low and/or when the expected probable weekly rainfall is low if the owner of the cistern does not want to risk the chance of an empty cistern. The demand for a reliable method for forecasting weekly rainfall is evident in this study.     

STOCHASTIC DYNAMIC PROGRAMMING FOR OPTIMUM RESERVOIR OPERATION1

ABSTRACT. For a multipurpose single reservoir a deterministic optimal operating policy can be readily devised by the dynamic programming method. However, this method can only be applied to sets of deterministic stream flows as might be used repetitively in a Monte Carlo study or possibly in a historical study. This paper reports a study in which an optimal operating policy for a multipurpose reservoir was determined, where the optimal operating policy is stated in terms of the state of the reservoir indicated by the storage volume and the river flow in the preceding month and uses a stochastic dynamic programming approach. Such a policy could be implemented in real time operation on a monthly basis or it could be used in a design study. As contrasted with deterministic dynamic programming, this method avoids the artificiality of using a single set of stream flows. The data for this study are the conditional probabilities of the stream flow in successive months, the physical features of the reservoir in question, and the return functions and constraints under which the system operates.     

APPLICATION OF THE GENETIC ALGORITHM FOR OPTIMIZING OPERATION RULES OF THE LiYuTan RESERVOIR IN TAIWAN1

ABSTRACT: A procedure to apply genetic algorithm to optimize operation rules is proposed and applied to the LiYuTan Reservoir in Taiwan. The designed operation rules are operation zones with discount rates of water supply. The first step of the procedure is to predefine the shape of boundary curves of operation zones according to reservoir storage routing. Then, relatively fewer variables are used to describe the curves, and a last genetic algorithm (GA) is applied to optimize the curves. The procedure is applied to the newly built LiYuTan Reservoir for increasing domestic water demands. Shortage index is used to evaluate the performance of operation zones. A year is divided into 36 operational periods, with each month containing three operational periods. The shortage indexes calculated in operational periods are 9.81, 8.27, and 7.13, respectively, for the reservoir without operation rules, applying operation zones optimized by GA with encoding 36 storage levels for each curve, and adopting operation zones optimized by GA with encoding the curves with predefined shape. The average deficits for the three cases are 77.2, 43.6, and 33.3 (10⁴ m³/day), respectively. The results indicate that operation zones optimized by the proposed procedure have smaller shortage indexes and lower average deficits. In addition, the optimized operation zones have less variation and thus are more practical for operation. Conclusively, the proposed procedure utilizing GA to optimize operation zones with predefined shape can provide better and realistic outcomes through limited iterations.     

UNCERTAINTY BASED OPERATION OF LARGE SCALE RESERVOIR SYSTEMS: DEZ AND KAROON EXPERIENCE1

ABSTRACT: Reservoir operation involves a complex set of human decisions depending upon hydrologic conditions in the supply network including watersheds, lakes, transfer tunnels, and rivers. Water releases from reservoirs are adjusted in an attempt to provide a balanced response to different demands. When a system involves more than one reservoir, computational burdens have been a major obstacle in incorporating uncertainties and variations in supply and demand. A new generation of stochastic dynamic programming was developed in the 1980s and 1990s to incorporate the forecast and demand uncertainties. The Bayesian Stochastic Dynamic Programming (BSDP) model and its extension, Demand Driven Stochastic Dynamic Programming (DDSP) model, are among those models. Recently, a Fuzzy Stochastic Dynamic Programming model (FSDP) also was developed for a single reservoir to model the errors associated with discretizing the variables using fuzzy set theory. In this study the DDSP and the FSDP models were extended and simplified for a complex system of Dez and Karoon reservoirs in the southwestern part of Iran. The simplified models are called Condensed Demand Driven Stochastic Programming (CDDSP) and Condensed Fuzzy Stochastic Dynamic Programming (CFSDP). The optimal operating policies developed by the CDDSP and the CFSDP models were simulated in a classical model and a fuzzy simulation model, respectively. The case study was used to demonstrate the advantages of implementing the proposed algorithm, and the results show the significant value of the proposed fuzzy based algorithm.     

剖析锅炉安全经济运行的十大认识误区

分析了有碍锅炉安全经济运行的汽压、水位等方面 10个错误认识 ,对锅炉运行人员、管理人员及专业研究人员有益     

大型露天矿爆破的事故树分析

建立了露天矿爆破质量的事故树并对其进行定性分析 ,利用最小割集法求出影响爆破质量的关键因素。在此基础上 ,提出了防范爆破事故、提高爆破效果的技术措施     

地震灾害紧急救援问题综述

防震减灾包括三大工作体系，即监测预报，震灾预防和紧急救援，本文根据地震灾害的特点和成灾规律，对目前国内外紧急救援工作中的组织机构，人力物力及专业技术等问题进行了综合论述。