A Differential Game Model of Oligopoly

Most of the literature on oligopoly deals with profit-maximizing firms engaging in “static” repetitive games. As the number of firms increases, the Nash-equilibrium strategy for each Cournot oligopolist converges to the competitive solution. In a two-person, zero-sum differential game model of duopoly [1] we introduced dynamic elements and explored alternative entrepreneurial goals. The duopolists endeavor to outsell each other subject to a no-loss constraint; the saturation of present markets by past sales and the impact on future goodwill by current advertisement are handled through “state variables.” The differential game formulation [1, 2] offers two advantages: (a) near perfect information leads to frequent existence of pure strategy equilibria and (b) the use of optimal control theory facilitates the characterization of the time structure of an equilibrium. However, the two-person, zero-sum framework is too restrictive while a general theory for solving n-person, non-zero sum differential games has still not been developed [3, 4].     

基于粗糙逻辑(RL)的微分对策理论

针对微分对策在实际应用上的困难,引入粗糙控制这一新颖的人工智能方法。粗糙集理论能刻画和处理不完整、不精确信息。在简略介绍了粗糙集、粗糙逻辑和粗糙控制大致思想的基础上,尝试将粗糙逻辑和粗糙控制引入微分对策,以追逃问题为例,初步探索了粗糙微分对策模型的建立方法。该对策模型体现了控制算法简单、迅速和易于实现的优点,也降低了微分对策要求精确数学模型和完备信息的困难。同时也将粗糙控制和模糊控制做了简单的比较。     

一种工程化的双门限辐射源目标识别方法

针对辐射源数量多、运动速度差异大、信息处理时效性要求高等特点,提出一类双门限辐射源目标识别方法;该方法首先构造信号与目标的相似度度量,通过双门限检测得到辐射源信号不属于任何目标、信号属于某个目标、模糊三类判定结论,对于模糊判定结果,构造差值门限进一步减小不确定性,提高目标识别能力;仿真结果表明所提出的方法能够快速有效地实现目标识别,便于工程化应用。     

A Differential Game Theoretic Approach for Two-Agent Collision Avoidance with Travel Limitations

This work presents a collision avoidance control strategy that solves the Hamilton-Jacobi-Isaacs (HJI) equation for an agent to quickly take action assuming a worst-case scenario. By doing so, the agent can develop a control strategy that is robust to the strategies of other agents with whom collision is possible. Consequently, if the governing dynamics of the agent are sufficient, then a collision can be avoided. We build on the idea of finding control solutions by using a differential game theoretic approach (Mettenheim and Breitner, 2009). This is beneficial because the opposing agent’s strategy is incorporated into the control by assuming it plays the worst-case actions. The approach in this work solves the zero-sum aspects of the control on-line using a fast solution method that operates over partitions in the state space (Goode et al., ASME J Dyn Syst Meas Control, 2011). We form the solution to the Homicidal Chauffeur game which is used to provide the control for an evader attempting to avoid a pursuer, an agent that deviates from its normal path and into that of the evader. Furthermore, the evader is constrained to remain within defined boundaries of its assigned travel area, such as a road lane, water channel, etc. The control strategy consists of three parts: (1) a zero-sum approximation of collision avoidance, (2) high-level path planning, and (3) low-level vehicle control. Each component is explained, and an example is given using a real robotic vehicle control system. Here, we show how the control can be implemented using a simple processor located on a vehicle that seeks to avoid a collision with another oncoming vehicle, making a left turn.     

How Not to Be Seen II: The Defenders Fight Back

For pt.I see ibid., vol. 5, no.1, p.67-69 (2007). This article discusses about stealthy software-that is, software that manipulates a computer in some way to avoid some aspect of its operation. The stealth is divided up into roughly three categories: passive, hooking, and hypervisor-based stealth detection. Most stealth malware hides by hooking and redirecting system calls, either at the kernel or the operating system (OS) level.     

基于Stackelberg-Markov非对等三方博弈模型的移动目标防御技术

易攻难守是当前网络安全面临的核心问题之一.移动目标防御技术对被保护系统的攻击面实施动态持续性变换,从而降低攻击者成功的概率.随着移动目标防御领域的研究进展,如何优化动态防御策略,实现成本和收益均衡的智能防御已经成为关键的研究点.移动目标防御的现有优化模型往往存在对目的性较强的实际攻守场景描述不当、无法预测参与者后续策略、缺乏对系统用户的考虑等问题.针对这些问题,本文创新性的将用户作为移动目标防御博弈中的第三方参与者,结合Stackelberg博弈和Markov模型来构建非对等三方博弈,以确定移动目标防御的最优策略.数学分析和仿真实验表明,本文提出的模型能够兼顾防御者和用户的成本和收益,避免过度的防御和不适宜的防御,有效的实现防御策略智能决策.     

二维差动电容式传感器的优化设计

将有限元法与最优化设计方法有机地结合起来,对二维差动电容式传感器的输出特性进行理论分析,并对传感器的结构参数进行最优化设计,给工程应用提供可靠的理论依据。     

基于八数码游戏的两种搜索策略比较

利用状态空间法描述八数码问题,将其抽象成为一个从起始状态搜索到达目标状态的路径的问题,并在Visual C++6.0环境下,用C++语言实现了其盲目搜索和启发式搜索算法。其中,盲目搜索采用的是宽度搜索和深度搜索,启发式搜索策略采用的是有序搜索。通过比较两种搜索策略的时间复杂度和空间复杂度,在搜索步骤较多的情况下,启发式搜索具有明显的优势,并在此结论的基础上分析了启发式搜索具有优势的原因。     

用Excel VBA实现比赛评分系统

探索计算机评卷系统的实现,为林业相同项目提供了有益的参考.     

基于差分盒维数的空间目标图像分割算法

基于差分盒子维数提出了一种针对空间目标的图像分割算法.首先根据空间环境目标自然背景与空间目标人造结构的特点差异,从分形理论的相似性上对星空背景进行分析,利用像素邻域灰度方法得到目标和背景的边界.其次,在对给定阈值及该阈值下图像的差分盒维数关系进行分析的基础上,提出基于灰度方差的阈值选择方法.最后给出空间目标图像分割算法的流程,通过诸多仿真空间图像处理验证该分割算法是有效的.     

双基地声纳两坐标目标三维定位算法精度分析

T／R—R型双基地声纳系统采用两坐标声纳对目标定位时,同时获得二个观测量。就可以对目标进行三维定位。如利用发射站方位角信息以及接收站距离和与方位角信息观测目标实现三维定位的算法,分别研究各观测量（双站角度测量误差,时间测量误差,站址测量误差等）、系统参数（基线长度等）以及环境参数（卢速波动）等因素对算法的定位精度的影响,通过数值仿真,做出各因素的误差几何分布图。仿真结果最示,系统的定位精度受双站角度测量误差的影响非常大,提高角度测量精度是提高系统定位精度的非常有效的方法。     

基于模糊微分对策多机空战组内协同的U解

鉴于协商微分对策多具有强非线性和不确定性特点,为避免非线性问题等带来求解上的困难和能处理不确定信息,基于T-S模糊微分对策的思想,对非线性的基于Utilitarian解(简称U解)的协商微分对策的状态方程和性能分别进行了模糊化和二次型化,构造出面向U解的协商微分对策的模糊线性化模型,研究了协商U解模型中加权系数的确定,并进一步探讨了在模糊线性协商微分对策系统下相应于U解的控制器的设计方法.研究工作和仿真结果可以说明,相对于Nash协商解,协商理论的U解更能反映整体效果,更易于推广.     

Pareto Equilibrium of Objections and Counterobjections in a Differential Three-Person Game

Automation and Remote Control - A linear-quadratic positional differential game of three persons is considered. Coefficient criteria are established under which there is no Nash equilibrium...     

The Pleadings Game

The Pleadings Game is a normative formalization and computational model of civil pleading, founded in Roberty Alexy's discourse theory of legal argumentation. The consequences of arguments and counterarguments are modelled using Geffner and Pearl's nonmonotonic logic,conditional entailment. Discourse in focussed using the concepts of issue and relevance. Conflicts between arguments can be resolved by arguing about the validity and priority of rules, at any level. The computational model is fully implemented and has been tested using examples from Article Nine of the Uniform Commercial Code.     

Comparison of Two Target Selection Methods for Two-Thumb Touchpad Typing

As an option for remote text entry, the possibility of bimanual text entry was explored using a touchpad that is called two-thumb touchpad typing (4-T). The design of a 4-T interface presents a few important design options to examine, and one of them is a target selection method. In this study, two 4-T interfaces were designed, called SlideType and FlyType. These interfaces use two different target selection methods, slide-and-click and fly-and-touch, respectively, and their prototypes were implemented using an optical hover-tracking touchpad. An experiment with the prototypes showed that FlyType was faster than SlideType and could achieve a text entry speed over 24 words per minute after practicing 2 hr. In addition, a microanalysis of thumb movements during the experiment showed that there are clear quantitative differences between the two methods in the degree of ballisticity of finger motions, in the concurrency of the movements of the two thumbs, and in the degree of integration between reaching and selecting actions, and that FlyType supports a more integral, ballistic, and concurrent motor skill than SlideType.     

利用Authorware软件开发贪食蛇游戏

贪食蛇游戏是款简单有趣的游戏。此文以Authorware7.0为开发工具，介绍了如何利用Authorware7．0中的函数变量实现贪食蛇游戏，涉及到界面设计、事件响应、时间限制以及声音设置等。     

OpenGL在视频游戏中的应用

OpenGL是一个图形系统的标准软件接口,使用OpenGL可以开发出高性能并能充分发挥硬件机能的图形程序。OpenGL被广泛使用在视频游戏、三维图像制作、工业设计等多个方面,它包含有120个不同的命令用于描述3D物体以及渲染方式。文中简述了在Windows平台下OpenGL在三维游戏开发中的地位,及它是如何将游戏画面快速高质地显示在屏幕上的。文中详述了使用OpenGL绘图,gltranslate函数实现对坦克的平移,利用OpenGL提供的函数实现坦克的3d效果。通过使用OpenGL,DirectInput在Windows下设计一个3D游戏的构架。     

OpenGL在视频游戏中的应用

OpenGL是一个图形系统的标准软件接口，使用OpenGL可以开发出高性能并能充分发挥硬件机能的图形程序。OpenGL被广泛使用在视频游戏、三维图像制作、工业设计等多个方面，它包含有120个不同的命令用于描述3D物体以及渲染方式。文中简述了在Windows平台下OpenGL在三维游戏开发中的地位，及它是如何将游戏画面快速高质地显示在屏幕上的。文中详述了使用OpenGL绘图，gltranslate函数实现对坦克的平移，利用OpenGL提供的函数实现坦克的3d效果。通过使用OpenGL，Directlnput在Windows下设计一个3D游戏的构架。     

利用Authorware软件开发贪食蛇游戏

贪食蛇游戏是款简单有趣的游戏。此文以Authorware7.0为开发工具,介绍了如何利用Authorware7.0中的函数变量实现贪食蛇游戏,涉及到界面设计、事件响应、时间限制以及声音设置等。