从南四湖水利管理局水管体制改革实践看管养分离运行机制

南四湖水利管理局自2006年以来按照国务院水管体制改革实施意见和水利部水管体制改革实施方案要求,全面推行了水利工程管理和维修养护分离。总结了水管体制改革取得的显著成效,结合基层工作实际分析了管理和养护运作过程中存在的一些问题,提出了完善措施及建议。     

水电站斜拉门机小车液压驱动机构研究

水电站双向门式启闭机的小车液压驱动机构的设计关键,是保持驱动小车的两侧液压缸同步运行,并采取措施防止活塞杆产生挠度和弯扭变形.液压管路对称布置,减少了管路对双缸同步的影响;液压系统采用“调速阀+旁路泄油纠偏回路”同步控制方式;关节轴承和滑动轴承组合采用铰接结构和抗挠托架,实现了液压缸对外界产生的挠、弯、扭作用的自适应.工程实践证明:小车液压驱动机构运行平稳、同步控制准确、无啃轨现象,满足实际工况需要.     

水库补偿效益分配问题研究

水库补偿效益分配的步骤:一是确定水库补偿效益的施益方和受益方;二是计算水库补偿效益值;三是选择科学合理并能使各方较满意的分配方法.在分析水库补偿效益不确定性、可变性和博弈性的基础上,探讨了梯级水库串联式发电和并联式水库发电补偿效益影响因子的识别方法.水库补偿效益的分配方法主要有多目标综合分析法、模糊综合评判法、熵权法、离差平方法等,但都存在不足,需要进一步研究完善.     

航行体有攻角出水全过程数值模拟

水下航行体高速出水时,空泡溃灭会产生较大的弯矩载荷,是其结构强度的主要设计依据.本文基于计算流体方法与结构动力学方法的单向耦合,建立了航行体有攻角出水全过程数值模拟方法,并针对抽象的典型工况进行了较大规模的并行计算,最终得到了航行体关键截面的全时程载荷响应.进一步通过分析航行体空泡形状和表面压力的演化特征,解释了航行体出水载荷的直接形成原因.     

东江流域基于水质的水资源有偿使用与生态补偿机制

回顾了东江流域生态补偿的政策与实践,认为基于发展机会损失下的生态补偿机制有悖于我国水资源国家所有的基本国情,是导致东江流域生态补偿进展缓慢的根本原因。提出建立基于水资源有偿使用的生态补偿机制:通过"使用者向国家付费,国家向保护者转移",实现对水源保护区的生态补偿。     

IPv6单播路由协议的新特性与应用研究

当前中小城市的下一代互联网建设比较迟缓,主要原因是对IPv6路由协议认识不足,缺少组网实践经验和工程技术指导。文中详细阐述了IPv6单播路由协议具备的新特性和工作机制,包括常用RIPng、OSPFv3、IPv6-IS-IS和BGP4+,使用思科仿真软件平台分别应用上述几种路由协议开展不同场景下的组网应用,设计了典型网络方案,给出了配置中的关键代码并分析了路由协议的运行状态和路由信息。仿真实验验证了IPv6单播路由协议的新特性,具有较好的工程技术实用价值,有助于促进现实IPv4网络向IPv6过渡的进程。     

On the simulation of expressional animation based on facial MoCap

MoCap(motion capture)-based animation is a hot issue in computer animation research currently.Based on the optical MoCap system,this paper proposes a novel cross-mapping based facial expression simulating method.To overcome the problem of the false upper and lower jaw correlation derived from the facial global RBFbased cross-mapping method,we construct a functional partition based RBF cross-mapping method.During model animating,enhanced markers are added and animated by our proposed skin motion mechanism.In addition,based on the enhanced markers,an improved RBF-based animating approach is raised to derive realistic facial animation.Further more,a pre-computing algorithm is presented to reduce computational cost for real-time simulation.The experiments proved that the method can not only map the MoCap data of one subject to diferent personalized faces but generate realistic facial animation.     

Application of parallel mechanism in varistructured quadruped/biped human-carrying walking chair robot

For the existing problems of walking chair robot such as simple function,lower bearing capacity and not walking in complex environment,a novel varistructured quadruped / biped human-carrying walking chair robot is proposed.The proposed robot could be used as biped and quadruped walking chair robots.Considering the conversion of the walking chair robot from the quadruped to the biped or vice versa,6-UPS and 2-UPS+UP(U,P and S are universal joint,the prismatic pair,and sphere joint,respectively) parallel mechanisms are selected as the leg mechanism of the biped walking robot and quadruped walking robot,respectively.Combining the screw theory and theory of mechanism,the degrees of freedom of the leg mechanism and the body mechanism in diferent motion states are computed so as to meet the requirements of mechanism design.The motion characteristics of the 2-UPS+UP parallel mechanism which is the key part of the walking chair robot are analyzed.Then,the workspace of the moving platform is drawn and the efect of the structural parameters on the workspace volume is studied.Finally,it is found that the volume of the workspace of the moving platform is bigger when the side length ratio and the vertex angle ratio of the fxed platform and the moving platform which are isosceles triangles are close to 1.This study provides a theoretical foundation for the prototype development.     

有源电力滤波器的自抗扰控制研究

针对采用PI控制器控制有源电力滤波器时存在谐波或基波电流指令而无法实现无静差调节,且数字化后会进一步增大稳态误差,使有源电力滤波器的补偿性能降低的问题,提出一种有源电力滤波器的自抗扰控制策略。该策略利用自抗扰控制器的非线性跟踪-微分器和扩张状态观测器分别处理参考输入和输出,并选择适当的状态误差,实现了对滤波的自动、精确补偿。仿真和实验结果表明,有源电力滤波器采用自抗扰控制策略后具有很强的鲁棒性、稳定性和适应性,控制性能有较大改善。