推行差异化设计以提高电网抗灾能力

通过分析重大自然灾害对电网的损害,提出了提高电网设防标准及差异化规划,并阐述了差异化规划的思路和原则。之后从自然灾害因素影响、保证负荷预测、重要线路选取、最小骨干网架形成以及投资估算几个方面对差异化规划的方法进行描述。最后,提出了差异化规划的相关建议。     

Approximate mathematical models in high-speed hydrodynamics

Approximate solutions of some problems in high-speed hydrodynamics are given, the solutions being based upon well-known approaches, such as the principle of independence of cavity expansion (Logvinovich), formulation of the problem of the immersion of a solid contour into liquid (Wagner), various models of cavity closure in its tail, etc. Theoretical studies of the dynamic properties of slender ventilated cavities are performed. The mathematical model of a cavity is obtained in the form of a system of nonlinear time-delay differential equations. The linear theory of cavity stability and oscillations is developed for various cavity types. The mechanism of nonlinear cavity oscillations accounting for gas-bubble detachment is considered, and the results of extensive numerical experimentation are presented. A theoretical model of cavity closure is proposed that develops the well-known Efros approach with a re-entrant jet. An approximate analysis of the model has been performed. A planar problem of the impact and immersion of an expanding cylinder into liquid with a cylindrical free surface of variable radius is solved in Wagner’s formulation.     

超空泡高速航行体动力学建模与控制设计

为了研究超空泡航行体的动力学建模和控制问题,根据空泡膨胀独立性原理,研究了空泡的记忆效应及其对空泡形态的影响,详细计算了超空泡航行体各部分所受的流体动力,计算过程中还考虑了空化器的定向效应和空泡尾部的上飘变形,研究了航行过程中尾翼效率变化规律,建立了超空泡航行体非线性动力学模型.设计了基于输入输出精确线性化的鲁棒极点配置控制器,深度跟踪性能较好,不足之处是控制输入饱和问题和滑行力的不利影响.为解决输入饱和问题,设计了预测控制方法并通过约束航行体尾部和空泡壁的距离使尾部不与空泡壁相接触,避免了滑行力的出现,有利于减少摩擦阻力,提高了航行体的运动稳定性.     

工艺设计中面向对象的事例表示和事例检索模型

重点介绍了零件的表示、索引和相似检索方法。建立了基于事例推理的CAPP系统的面向对象零件事例表示和检索模型，该模型适用于各类零件，可以对具有复杂层次结构的事例进行表示并计算相似度。可以在具有不同属性的不同事例之间进行相似性计算，解决了异构事例的相似性比较的问题。采用Visual Basic和SQL Server实现该模型的原型系统HOPE－CAPP。     

浅谈住宅小区地下车库的设计

对住宅小区地下车库的规划布局、平面布置、竖向设计等多个设计环节中一些带有共性的问题进行了总结和探讨,解决了住宅小区的停车问题,有效提高了车库率,改善了小区的绿化环境。     

Numerical and experimental analyses of hydrodynamic performance of a channel type planing trimaran

This paper studies the hydrodynamic performance of a channel type planing trimaran. A numerical simulation is carried out based on a RANS-VOF solver to analyze the hydrodynamic performance of the channel type planing trimaran. A series of hydrodynamic experiments in towing tank were carried out, in which both the running attitude and the resistance performance of the trimaran model were recorded. Some hydrodynamic characteristics of the channel type planning trimaran are shown by the results. Firstly, the resistance declines significantly, with the forward speed across the high-speed resistance peak due to the combined effects of the aerodynamic and hydrodynamic lifts. Secondly, the resistance performance is influenced markedly by the longitudinal positions of centre of the gravity and the displacements. Besides, the pressure distribution on the hull and the two-phase flow in the channel are discussed in the numerical simulations.     

安徽电网电源规划及调峰能力平衡研究

随着跨区特高压交、直流电网的快速发展,全国范围内的资源优化配置能力不断加强,安徽省未来将接受大量的区外来电,省内电源发展受区外来电的影响也越来越大。区外来电相比省内电源有其特殊性,调峰容量不受省网控制。安徽省自身的能源分布特点决定了未来省内仍主要发展火电装机,综合考虑区外来电的影响,提出电源规划的新思路,即从调峰能力平衡的角度,确定全省2015、2020年最基本的火电装机容量,为今后省内火电发展提供指导。     

A beam search approach to the container loading problem

The single container loading problem is a three-dimensional packing problem in which a container has to be filled with a set of boxes. The objective is to maximize the space utilization of the container. This problem has wide applications in the logistics industry. In this work, a new constructive approach to this problem is introduced. The approach uses a beam search strategy. This strategy can be viewed as a variant of the branch-and-bound search that only expands the most promising nodes at each level of the search tree. The approach is compared with state-of-the-art algorithms using 16 well-known sets of benchmark instances. Results show that the new approach outperforms all the others for each set of instances.     

提高我国环境规划与环境管理有机统一性的方法探讨

借鉴了美国流域保护方法（WPA）等实践中的成功经验之后认为,为了提高我国环境规划与环境管理的有机统一,还需做好几方面的工作,包括：环境规划与环境管理引入广泛的公众参与,环境规划与环境管理同时引入GIS的支持,以及必须严格执行环境管理的科学程序。     

利用数字高程模型计算土石方量的程序方法

介绍了一种利用数字高程模型(DEM)计算土石方量的程序方法，该软件系统在土石方量测量与计算实践中取得了良好的效果，为计算机技术在测绘工程中的应用提供了新的思路。