军队网络空间作战能力的建设

当今世界,随着信息技术的飞速发展以及全球作战环境的日趋多样化,网络空间已经成为世界各国军队努力建设的重要作战域,网络空间作战能力也已经成为一种全新的作战能力。如同制海权、制空权、制天权一样,争夺制网空权也将逐渐演变成为世界军事强国维持军事绝对优势的重要战略组成。文章从概念、技术和装备层面入手,分析了军队网络空间作战能力的基本建设情况,以期对网络空间技术开发,能力建设提供借鉴。     

基于嵌入式系统异构总线的原子协议锥匹配

针对异构总线嵌入系统难以进行部件移植和接口互换问题,提出基于嵌入系统异构总线的原子协议锥匹配方法,分析接口协议原子操作,构建协议锥,阐述偶锥模型的相关性和时序特性。在抽象空间中进行协议亲缘进程识别及综合适配,并引导协议空间的接口转换,实现接口的自动匹配。     

Geometric analysis of nondeterminacy in dynamical systems

This article intends to provide some new insights into concurrency using ideas from the theory of dynamical systems. Inherently discrete concurrency corresponds to a parallel continuous concept: a discrete state space corresponds to a differential manifold, an execution path corresponds to a flow line of a dynamical system. To model non-determinacy within dynamical systems, we introduce a new geometrical object, a section cone. A section cone is a convex set in the space of vector fields, all elements having the same singular points. We show that it is enough to consider flow lines of a single vector field in order to capture the behavior of all flow lines in the section cone up to homotopy (corresponding to equivalence of executions).     

圆锥裁剪BLOB的视频目标检测方法

真实场景的视频目标检测需要消除阴影、反射和鬼影等噪声的影响,以检测出运动目标和静止目标.为了实现系统性的视频目标检测,提出一种自适应圆锥裁剪联通块(TC-BLOB)榆测方法.基于BLOB知识,将3D颜色空间变换为"夹角-模差"2D空间后,定义一套圆锥裁剪规则划分出阴影BLOB和反射BLOB;再以一种持久化记忆PM方法判别出鬼影BLOB;最后改进双背景模型检测出静止目标和运动目标.采用不同环境视频进行实验的结果表明,文中方法足有效的,并有独立于后续跟踪的优点.     

High gain feedback,tolerance, and stabilization of linear systems

The problem of stabilizing linear continuous-time systems is revisited with the objective of investigating the tolerance allowed in the implementation of stabilizing feedback controllers. It is shown that, for high gain feedback, this tolerance can be described by a cone in the feedback parameter space, called the “tolerance cone”. The tolerance cone describes fractional (percentage) errors the feedback controller can tolerate without jeopardizing the internal stability of the controlled system. The larger the vertex angle of this cone, the more tolerance is available when implementing the controller. The vertex angle of the tolerance cone is determined by the proximity to singularity of a certain matrix derived from the controlled system.     

Segmented Linear Subspaces for Illumination-Robust Face Recognition

All images of a convex Lambertian surface captured with a fixed pose under varying illumination are known to lie in a convex cone in the image space that is called the illumination cone. Since this cone model is too complex to be built in practice, researchers have attempted to approximate it with simpler models. In this paper, we propose a segmented linear subspace model to approximate the cone. Our idea of segmentation is based on the fact that the success of low dimensional linear subspace approximations of the illumination cone increases if the directions of the surface normals get close to each other. Hence, we propose to cluster the image pixels according to their surface normal directions and to approximate the cone with a linear subspace for each of these clusters separately. We perform statistical performance evaluation experiments to compare our system to other popular systems and demonstrate that the performance increase we obtain is statistically significant.     

求图符号控制数的完全算法研究

确定图的符号控制数是NP-难度的问题。针对求解该问题的完全算法即能求得精确最优解的算法进行了研究,提出了几个启发式的限界策略,给出了两个完全算法:回溯算法和A算法。计算实验表明,针对随机产生的问题实例,用这两个算法求解时所生成的结点数目还不到其状态空间树中结点总数目的千分之五。对这两个算法也进行了比较。     

Rapid Analysis of Interval Value Ordering

Two models of ranking the interval-defined objects were described. They are based on the principles of domination in probability and utility. Proposed was a two-stage ranking procedure where the objects are first ranked according to the model of domination in probability and then this ranking is corrected using the model of domination in utility.     

From few to many: illumination cone models for face recognitionunder variable lighting and pose

We present a generative appearance-based method for recognizing human faces under variation in lighting and viewpoint. Our method exploits the fact that the set of images of an object in fixed pose, but under all possible illumination conditions, is a convex cone in the space of images. Using a small number of training images of each face taken with different lighting directions, the shape and albedo of the face can be reconstructed. In turn, this reconstruction serves as a generative model that can be used to render (or synthesize) images of the face under novel poses and illumination conditions. The pose space is then sampled and, for each pose, the corresponding illumination cone is approximated by a low-dimensional linear subspace whose basis vectors are estimated using the generative model. Our recognition algorithm assigns to a test image the identity of the closest approximated illumination cone. Test results show that the method performs almost without error, except on the most extreme lighting directions     

A method of transferring cones of intersection form to cones of sum form and its applications in data envelopment analysis models

This paper develops an algebra-based method for transferring polyhedral cones of intersection form to the cones of sum form. The method recursively identifies all the extreme rays of the cone of intersection form without adding any pre-assumption on it, which allows us to represent the cone with a finitely generated form (sum form). Our method takes m recursions dealing with each of the m homogeneous linear inequalities in each recursion. The implementation is efficient in terms of both computational time and storage space. Illustrative examples are provided. We also show how the procedure can be applied to generalized cone ratio data envelopment analysis models.     

基于Skyline的搜索结果排序方法

针对现有垂直搜索引擎的排序结果存在多样性差和冗余度高的问题,提出了一种基于Skyline的搜索结果排序方法。该方法通过计算搜索结果的轮廓等级、支配度和覆盖度作为排序依据,并且为加快轮廓等级和支配度的计算,使用了一种基于Bitmap的轮廓等级和支配度计算算法。实验结果表明,该方法的排序结果具有低冗余度和高多样性的优点,并且具有更快的轮廓等级和支配度计算速度。     

Object-Colour Manifold

Colorimetry can predict which lights will look alike. Such lights are called metameric. Two lights are metameric if they have the same tri-stimulus values. Using the tri-stimulus values as Cartesian coordinates one can represent light colours as points in a 3D space (referred to as the colorimetric space). All the light colours make a tri-dimensional manifold which can be represented as a circular cone in the colorimetric space. Furthermore, colorimetry also claims that reflecting objects illuminated by the same light will look alike as soon as they reflect metameric lights. All the object colours are then represented as a closed solid inscribed in the light colour cone provided the illumination is fixed. However, as argued in this article, the reflected light metamerism does not guarantee that the reflecting objects will look identical (referred to as colour equivalence), especially when there are multiple illuminants. Moreover, colour equivalence cannot be derived from metamerism. The colour of a reflecting object under various illuminations is shown to be specified by six numbers (referred to as its six-stimulus values) that can be established by experiment. Using the six-stimulus values one can represent the colours of all the reflecting objects illuminated by various illuminants as a cone (without a vertex) through a 5D ball.     

HE射弹破片场仿真模型研究

在HE射弹破片场呈圆锥形、破片分散在各个子锥面、破片数在飞散锥内随锥角服从均匀分布的前提下,假设同一锥面层上相邻两破片间的距离与其所在层到相邻外层锥面的层间距相等;根据“宏观可控、微观随机”的破片分布实际,引入相应的随机变量,推导了射弹静爆时单一破片的飞散角及方位角,给出了相应的轨迹方程和速度计算公式;推导了动态条件下破片相对大地和相对目标的速度计算公式和飞行轨迹参数方程;根据射弹破片质量服从Mott分布、破片质量在飞散空间均匀分布的假设,推导了单一破片的质量。     

Control space of natural-language syntactic structures

A formal model of the structure of natural-language sentences is considered, based on the concept of control space. The proposed model allows for recursion of predicative and attributive relations in the language and generalizes the linguistic models of domination trees and constituent systems. It is designed for efficient implementation in parallel computing systems.Translated from Kibernetika, No. 3, pp. 11–17, May–June 1990.     

Geometry of Pursuit-Evasion on Second Order Rotation Surfaces

Differential games with simple motionin a game space with non-unique shortest geodesic line havephase portraits with complicated structure of singular surfaces.The successful solution of such games on a family of two-dimensionalcones [1] was based to the large extent on the parameter analysisof the problem. In the present paper the results of pursuit gameon a cone of one sheet are extended to the game on the full two-sheetcone. The latter surface is included in one-parametric familyof rotation surfaces (each of which is characterized by two moreparameters), and the game on it is considered as the generatingproblem for the analysis of the games on the perturbed surfaces.The paper continues the previous investigations of the authors.In [2], [3] some local results are obtained for the games onRiemannian manifolds. In [1], [2] the game problems are solvedfor a two-dimensional cone, in [4], [5] one sheet of a double-sheetedrotation hyperboloid is considered as game space and geometricalproperties of trajectories are analyzed.     

Polynomial-time algorithms for weighted efficient domination problems in AT-free graphs and dually chordal graphs

An efficient dominating set (or perfect code) in a graph is a set of vertices the closed neighborhoods of which partition the vertex set of the graph. The minimum weight efficient domination problem is the problem of finding an efficient dominating set of minimum weight in a given vertex-weighted graph; the maximum weight efficient domination problem is defined similarly. We develop a framework for solving the weighted efficient domination problems based on a reduction to the maximum weight independent set problem in the square of the input graph. Using this approach, we improve on several previous results from the literature by deriving polynomial-time algorithms for the weighted efficient domination problems in the classes of dually chordal and AT-free graphs. In particular, this answers a question by Lu and Tang regarding the complexity of the minimum weight efficient domination problem in strongly chordal graphs.     

Linear cone-invariant control systems and their equivalence

In this paper, we study invariant control systems that generalise positive systems. A characterisation of linear control systems invariant on polyhedral cones (corner regions) in the state-space, called cone-invariant linear control systems, is established both for the inputs taking values in a polyhedral cone in the control space and for the inputs taking values in an affine polyhedral cone. The problem of equivalence between control systems invariant on corner regions is introduced. For cone-invariant linear control systems, we study invariance-preserving state-equivalence and invariance-preserving feedback-equivalence and present characterisations of both notions of equivalence.     

任意图支配集精确算法回顾

该文综述了任意图支配集精确算法分析和设计的新进展.支配集问题是经典NP完全问题,很多问题都能与它相联系.我们针对最小支配集、最大独立集、最小独立支配集、最小连通支配集、最小加权支配集问题提供了详尽算法描述和实例说明,以使文章自包含方便阅读.文中还讨论了诸如分支简化策略、复杂度分析、测度分析、记忆等技术.自Claude Berge首次准确阐述现代图支配概念后,经过很长一段时期的沉寂,关于指数时间精确算法设计的研究热情在过去五年中显著增涨.除回顾这些最新成果之外,作者还盼望国内研究团体能更加重视这个快速发展的研究领域.     

Distance Between a Point and a Convex Cone in $n$ -Dimensional Space: Computation and Applications

This paper presents an algorithm to compute the minimum distance from a point to a convex cone in $n$-dimensional space. The convex cone is represented as the set of all nonnegative combinations of a given set. The algorithm generates a sequence of simplicial cones in the convex cone, such that their distances to the single point converge to the desired distance. In many cases, the generated sequence is finite, and therefore, the algorithm has finite-convergence property. Recursive formulas are derived to speed up the computation of distances between the single point and the simplicial cones. The superior efficiency and effectiveness of this algorithm are demonstrated by applications to force-closure test, system equilibrium test, and contact force distribution, which are fundamental problems in the research of multicontact robotic systems. Theoretical and numerical comparisons with previous work are provided.