Maximizing sets and fuzzy Markoff algorithms

A fuzzy algorithm is an ordered set of fuzzy instructions that upon execution yield an approximate solution to a given problem. Two unrelated aspects of fuzzy algorithms are considered in this paper. The first is concerned with the problem of maximization of a reward function. It is argued that the conventional notion of a maximizing value for a function is not sufficiently informative and that a more useful notion is that of a maximizing set. Essentially, a maximizing set serves to provide information not only concerning the point or points at which a function is maximized, but also about the extent to which the values of the reward function approximate to its supremum at other points in its range. The second is concerned with the formalization of the notion of a fuzzy algorithm. In this connection, the notion of a fuzzy Markoff algorithm is introduced and illustrated by an example. It is shown that the generation of strings by a fuzzy algorithm bears a resemblance to a birth-and-death process and that the execution of the algorithm terminates when no more “live” strings are left     

Lukasiewicz命题逻辑中命题的Choquet积分真度理论

将已有的不确定性测度概念引入到了Lukasiewicz命题逻辑中的全体赋值之集上,然后利用McNaughton函数关于该不确定性测度的Choquet积分定义了命题的Choquet积分真度概念.证明了当赋值空间上的不确定性测度满足有限可加性时Choquet积分真度函数就具有良好性质,由此可诱导出命题集上的一个伪距离,进而可建立逻辑度量空间并展开程度化推理,特别是证明了当赋值空间上的不确定性测度取为Borel概率测度时Choquet积分真度函数就退化为概率计量逻辑中的Borel概率真度函数.本文是已有命题逻辑概率计量化工作的继续与深入,为表示逻辑命题间不确定性的非线性关系提供了一种推理框架.     

Flat zones filtering, connected operators, and filters byreconstruction

This correspondence deals with the notion of connected operators. Starting from the definition for operator acting on sets, it is shown how to extend it to operators acting on function. Typically, a connected operator acting on a function is a transformation that enlarges the partition of the space created by the flat zones of the functions. It is shown that from any connected operator acting on sets, one can construct a connected operator for functions (however, it is not the unique way of generating connected operators for functions). Moreover, the concept of pyramid is introduced in a formal way. It is shown that, if a pyramid is based on connected operators, the flat zones of the functions increase with the level of the pyramid. In other words, the flat zones are nested. Filters by reconstruction are defined and their main properties are presented. Finally, some examples of application of connected operators and use of flat zones are described.     

Two-variable polynomials: intersecting zeros and stability

In order to construct two-variable polynomials with a certain zero behavior, the notion of intersecting zeros is studied. We show that generically two-variable polynomials have a finite set of intersecting zeros, and give an algorithm on how to construct a polynomial with the desired intersecting zeros. Relations with the Cayley-Bacharach theorem are addressed. In addition, we will also address the case when stable polynomials are sought.     

Performance analysis of dynamic OFDMA systems with inband signaling

Within the last decade, the orthogonal frequency- division multiplexing (OFDM) transmission scheme has become part of several standards for wireless systems. Today, OFDM is even a candidate for fourth-generation wireless systems. It is well known that dynamic OFDMA systems potentially increase the spectral efficiency. They exploit diversity effects in time, space, and frequency by assigning system resources periodically to terminals. Informing the terminals about new assignments creates a signaling overhead. Up to now, this overhead has not been taken into account in studies on dynamic orthogonal frequency-division multiplexing access (OFDMA) systems. Yet this is crucial for a realistic notion of the performance achieved by dynamic approaches. In this paper, we close this gap. We introduce two forms of representing the signaling information and discuss how these affect system performance. The study of the signaling impact on the performance is conducted for an exemplary dynamic approach. We find that the throughput behavior of dynamic OFDMA systems is significantly influenced by the signaling overhead. In many situations, neglecting the overhead leads to wrong performance conclusions. Also, the performance difference between dynamic and static schemes is now much more sensible to the specific parameter set of the transmission scenario (e.g., frame length, subcarrier number, etc.). This leads to the proposal of access points which should adapt certain system parameters in order to provide optimal performance.     

加强预防检测,提高企业网安全

介绍企业网的概念和优点，分析企业网存在的不安全因素，针对加强预防检测措施，介绍提高网络安全的几项策略，尤其是针对UNIX系统，如何设置记录日志，加强入侵检测，应对可能的攻击，提高网络安全性。     

一种斜视画幅遥感相机异速像移计算与补偿实现

以一种斜视胶片步进画幅相机为例,介绍了一种基于该相机的像移补偿策略及具体实现过程。画幅相机由于横向视场较大,使得每幅横向各个视场目标对应物距各异,最终导致目标像相对探测器产生了异速像移。对产生异速像移实质给出了数学推导,对偏流机构存在的必要性进行了分析,提出了一种利用两轴旋转扫描镜,同时结合旋转偏流机构和曝光帘缝的像移补偿方案。最后,在已知相机俯角和视场角等信息情况下,推导出了具体的像移补偿公式。     

Analysis of CCME: Coevolutionary Dynamics, Automatic Problem Decomposition, and Regularization

In most real-world problems, we either know little about the problems or the problems are too complex to have a clear vision on how to decompose them by hand. Thus, it is usually desirable to have a method to automatically decompose a complex problem into a set of subproblems and assign one or more specialists to each subproblem. The cooperative coevolutionary mixture of experts (CCME) model was designed to automatically decompose problems by combining the global optimization power of cooperative coevolution with the divide-and-conquer ability of mixture of experts. This paper analyzes how CCME decomposes complex classification problems through a principal-component-analysis-based visualization tool. The visualization shows that CCME decomposes the problem by driving different experts toward different regions of the input space. The paper also investigates the effect of regularization, using learning by forgetting (LF), on CCME. LF significantly reduces the structural complexity of CCME while maintaining the classification accuracy.     

Privacy,identity and security in ambient intelligence: A scenario analysis

The success of ambient intelligence (AmI) will depend on how secure it can be made, how privacy and other rights of individuals can be protected and how individuals can come to trust the intelligent world that surrounds them and through which they move. This article addresses these issues by analysing scenarios for ambient intelligence applications that have been developed over the last few years. It elaborates the assumptions that promotors make about the likely use of the technology and possibly unwanted side effects. It concludes with a number of threats for personal privacy that become evident.     

Linear controller design: limits of performance via convexoptimization

In this tutorial, an approach to the analysis and design of linear control systems based on numerical convex optimization over closed-loop maps is presented. Convexity makes numerical solution effective: it is possible to determine whether or not there is a controller that achieves a given set of specifications. Thus, the limit of achievable performance can be computed. To provide a context for the material presented, a brief overview of control engineering is given. A broad outline of various approaches to control design for linear and time-invariant systems is presented, including their advantages and disadvantages, for purposes of comparison with the approach presented. It is shown that many performance specifications have natural and useful geometric interpretations, and the notion of a closed-loop convex design specification is defined. The performance requirement that the closed-loop system be stable is discussed. It is shown that many performance specifications can be expressed as convex constraints on closed-loop performance specifications, and how some of these can be expressed as convex constraints on closed-loop transfer matrices is examined     

Phonemic hidden Markov models with continuous mixture outputdensities for large vocabulary word recognition

The authors demonstrate the effectiveness of phonemic hidden Markov models with Gaussian mixture output densities (mixture HMMs) for speaker-dependent large-vocabulary word recognition. Speech recognition experiments show that for almost any reasonable amount of training data, recognizers using mixture HMMs consistently outperform those employing unimodal Gaussian HMMs. With a sufficiently large training set (e.g. more than 2500 words), use of HMMs with 25-component mixture distributions typically reduces recognition errors by about 40%. It is also found that the mixture HMMs outperform a set of unimodal generalized triphone models having the same number of parameters. Previous attempts to employ mixture HMMs for speech recognition proved discouraging because of the high complexity and computational cost in implementing the Baum-Welch training algorithm. It is shown how mixture HMMs can be implemented very simply in unimodal transition-based frameworks by allowing multiple transitions from one state to another     

Sur la théorie des signaux numériques d’ordre fini

The practical limitation of the number of terms used in digital operations about sampled signals leads to the notion of vectorsignal. The author makes clear the meaning and studies the main properties of this notion. The complex representation of those digital signals has to be used in both dual forms. Linear transformations fall also into two dual categories, convolution and modulation. A special case of convolution (and of modulation) is that of digital derivation the notion and properties of which are specified. These basic results enable to define the instantaneous frequency and the group time of the vectorsignals. It is also possible to derive from them, by extension of the concepts proposed by Gabor and Ville, the joint density of a signal in spectrum and time. The study is completed by a short review of methods for applying the theoretical results to any given digital signal.     

企业的产品质量成本核算方法

本文介绍了在完善质量管理的基础上,如何进一步开展质量成本管理和在提升竞争力的过程中充分发挥质量体系应有的作用,并指出了质量成本的构成、质量成本核算的意义,并对企业如何开展好质量成本管理方法提出了几点建议.     

Varactor characteristics, oscillator tuning curves, and AM-FM conversion

A simple analysis relates the small-signal specification of a varactor's capacitance to an oscillator's tuning curve. The notion of an effective capacitance across the amplitude of oscillation is introduced. The analysis also explains how the varactor converts AM noise on the oscillation into FM, which is phase noise. The analysis is experimentally validated.     

Quality of service in telecommunications. I. Proposition of a QoSframework and its application to B-ISDN

The the quality of service (QoS) concept is becoming an ever more important issue in telecommunication and computer communication. The article focuses on the QoS notion and concept. The definition of QoS in the International Telecommunications Union-Telecommunications Sector (ITU-T) recommendations and the International Standards Organization (ISO) standards is analysed. Little is known about the asynchronous transfer mode (ATM) performance requirements of the broadband integrated services digital network (B-ISDN) services, especially for multimedia applications. This is because the ATM performance requirements of multimedia applications depend not only on the diverse QoS requirements from application and user, but also on the protocol stacks and scheduling in end systems. Therefore, in order to guarantee QoS to the user, it is necessary to introduce a set of QoS parameters whose properties indicate the nature and requirements of the layered protocol stack. We describe how a proposed QoS framework can be applied to B-ISDN as a specific network. The QoS aspects related to B-ISDN signaling (the control plane) and the QoS aspects related to layer and plane management (the management plane) are described. We also describe how the QoS framework resides in a protocol stack and works together with the B-ISDN network management and signaling     

Convolution algorithms,based on the crt (Chinese Remainder Theorem)

It is well-known that most contemporary algorithms for calculating discrete convolutions are based on the Chinese remainder theorem (CRT). In this paper, the problem of calculating convolutions or equivalently, polynomial products, is addressed from the opposite point of view. Instead of showing how a given polynomial product (most often, a circular convolution) can be calculated by means of the CRT, we investigate which polynomial product algorithms make the most efficient use of the CRT. One set of polynomial product algorithms is subsequently discussed in detail. Amongst others, it is shown that the circular convolution is the most efficient representative in this set.     

利用PXE技术组建无盘Win98工作站

介绍利用PXE技术组建无盘windows 98局域网的步骤。重点讲述一种不要PXEB00TROM芯片，而是将PXE启动代码写入BIOS的组网方法和建网中应重点注意的问题。     

Circuit partitioning for logic synthesis

The authors introduce a circuit partitioning method based on analysis of reconvergent fan-out. A corolla is defined as a set of overlapping reconvergent fan-out regions. The authors partition the circuit into a set of disjoint corollas and use the corollas to resynthesize the circuit. The authors develop the notion of resynthesis potential of a logic circuit and use it to select corollas that resynthesize with most gain. It is shown that resynthesis of large benchmark circuits using the corollas consistently reduces transistor pairs and layout area while improving delay and testability. The use of don't cares to further minimize the corollas in the local context and the global context is explored     

Nonlinear echoes, phase conjugation, time reversal, and electronic holography

In this paper we review the experiments on nonlinear echo phenomena during the last three decades, from spin echoes to echoes in piezoelectric powders. We show how the common principle is one of a physical Fourier transform space in which time reversal is brought about through phase conjugation. It will be seen how this leads to intriguing applications in signal processing, signal storage, and electronic holography.     

安全MPLS技术研究

介绍了多协议标记交换技术的工作原理、组网、实现,并且着重阐述了如何建立安全信道以及如何进行安全通信。提出了如何构建一个安全MPLS网络。