Survivable network design under optimal and heuristic interdiction scenarios

We examine the problem of building or fortifying a network to defend against enemy attacks in various scenarios. In particular, we examine the case in which an enemy can destroy any portion of any arc that a designer constructs on the network, subject to some interdiction budget. This problem takes the form of a three-level, two-player game, in which the designer acts first to construct a network and transmit an initial set of flows through the network. The enemy acts next to destroy a set of constructed arcs in the designer’s network, and the designer acts last to transmit a final set of flows in the network. Most studies of this nature assume that the enemy will act optimally; however, in real-world scenarios one cannot necessarily assume rationality on the part of the enemy. Hence, we prescribe optimal network design algorithms for three different profiles of enemy action: an enemy destroying arcs based on capacities, based on initial flows, or acting optimally to minimize our maximum profits obtained from transmitting flows.     

一种新的高温超导磁体电磁结构优化设计方法

本文阐述了用于高温超导磁体电磁结构优化设计的一种新方法,与一般优化方法不同之处在于其不用定义磁体的初始结构形状,采用该方法可以得到满足规格和性能要求的较佳磁体结构.通过此方法优化设计了一个中心磁场为3T的Bi系高温超导磁体,其设计结果与满足同样要求且经过优化的单螺管高温超导磁体的设计结果作了对比,由结果表明该方法具有很好的优化效果.     

Self-Orthogonal 3-(56,12,65) Designs and Extremal Doubly-Even Self-Dual Codes of Length 56

In this paper, we show that the code generated by the rows of a block-point incidence matrix of a self-orthogonal 3-(56,12,65) design is a doubly-even self-dual code of length 56. As a consequence, it is shown that an extremal doubly-even self-dual code of length 56 is generated by the codewords of minimum weight. We also demonstrate that there are more than one thousand inequivalent extremal doubly-even self-dual [56,28,12] codes. This result shows that there are more than one thousand non-isomorphic self-orthogonal 3-(56,12,65) designs. AMS Classification: 94B05, 05B05     

短波通滤光片膜系设计

详细介绍用等效折射率概念设计短波通滤光片的原理和计算方法。根据原理和方法，选择二氧化钛（TiO2）作为高折射率材料、二氧化硅（SiO2）作为低折射率材料。首先从理论上计算出用这2种材料设计的波长λ=950～1150nm的短波通滤光片所需要的周期数，然后给出短波通滤光片的主膜系和光谱曲线。由于据此周期数设计出的膜系光谱曲线在750～810nm处的透过率不符合要求，因此对该膜系进行了改进。依照改进的设计进行多次制备，最终制备出了符合要求的短波通滤光片，找到了最佳制备工艺和方法。最后，对制备出来的短波通滤光片薄膜进行了各种环境实验。实验结果表明，膜层的各项指标符合设计要求。     

Parking Capacity and Pricing in Park'n Ride Trips: A Continuous Equilibrium Network Design Problem

In this paper we consider the problem of designing parking facilities for park'n ride trips. We present a new continuous equilibrium network design problem to decide the capacity and fare of these parking lots at a tactical level. We assume that the parking facilities have already been located and other topological decisions have already been taken.The modeling approach proposed is mathematical programming with equilibrium constraints. In the outer optimization problem, a central Authority evaluates the performance of the transport network for each network design decision. In the inner problem a multimodal traffic assignment with combined modes, formulated as a variational inequality problem, generates the share demand for modes of transportation, and for parking facilities as a function of the design variables of the parking lots. The objective is to make optimal parking investment and pricing decisions in order to minimize the total travel cost in a subnetwork of the multimodal transportation system.We present a new development in model formulation based on the use of generalized parking link cost as a design variable.The bilevel model is solved by a simulated annealing algorithm applied to the continuous and non-negative design decision variables. Numerical tests are reported in order to illustrate the use of the model, and the ability of the approach to solve applications of moderate size.     

红外耦合光学系统设计

红外目标模拟器由红外目标图像发生器和投影光学系统组成。该红外光学系统是一个要求与2个导引光学系统的光学技术参数相匹配的长焦距、大视场和具有像方远心光路的中红外光学系统。叙述用于红外目标模拟器的红外耦合光学系统的设计原理，提出它与导引光学系统一起可组成放大倍率M=4.5×的红外投影光学系统，并指出IR CRT产生的图像通过红外投影光学系统可成像在导引接收器上。针对给出的红外耦合光学系统的设计特点和技术要求，光学材料选取硅（Si） 锗（Ge） 硅（Si），采用简单的柯克三片式结构完成光学系统设计。设计评价结果表明，该系统的光学性能和成像质量均满足设计指标要求。     

磁性纳米颗粒膜的微磁学模拟

用微磁学方法对磁性纳米颗粒膜的磁特性进行了模拟，采用的模型是由122个磁性纳米颗粒组成的面心立方(fcc)结构体系.结果表明：在该体系中，偶极相互作用对体系的静态磁结构的影响显著，而交换相互作用的影响表现不明显.在此基础上，本文还采用有效媒质理论计算分析了磁性合金颗粒不同体积比时颗粒膜的磁谱和表征电磁参量发生显著变化的逾渗现象和逾渗阈值.并完成了对高磁损耗磁性纳米颗粒膜的材料设计. 关键词： 微磁学 纳米颗粒膜 逾渗阈值 磁导率 材料设计     

低电阻测量设计实验中电位差计指针不稳的解决方法

本文分析了J33Q型电位差计在实验中指针不稳的原因,并提出了解决的办法。     

超大规模集成电路光学光刻技术的现状与展望

光学光刻是目前超大规模集成电路(VLSI)制备中主要的微米和亚微米的图形加工技术,这一技术将继续保持其主导地位成为90年代VLSI发展的关键。本文综述了近年来光学光刻工艺的发展,主要介绍了G线(436nm)、Ⅰ线(365nm)和准分子激光光刻的现状,并对实现高的光学光刻分辨率所必须解决的透镜设计、套准精度和像场面积等问题作了详细描述。最后展望了发展方向、     

Current methods for site-directed structure generation

Summary There has been a rapid growth of interest in techniques for site-directed drug design, fuelled by the increasing availability of structural models of proteins of therapeutic importance, and by studies reported in the literature showing that potent chemical leads can be obtained by these techniques. Structure generation programs offer the prospect of discovering highly original lead structures from novel chemical families. Due to the fact that this technique is more-or-less still in its infancy, there are no case studies available that demonstrate the use of structure generation programs for site-directed drug design. Such programs were first proposed in 1986, and became commercially available in early 1992. They have shown their ability to reproduce, or suggest reasonable alternatives for, ligands in well-defined binding sites. This brief review will discuss the recent advances that have been made in the field of site-directed structure generation.