结合包光滑性的半监督多示例核学习方法

以往半监督多示例学习算法常把未标记包分解为示例集合,使用传统的半监督单示例学习算法确定这些示例的潜在标记以对它们进行利用。但该类方法认为多示例样本的分类与其概率密度分布紧密相关,且并未考虑包结构对包分类标记的影响。提出一种基于包层次的半监督多示例核学习方法,直接利用未标记包进行半监督学习器的训练。首先通过对示例空间聚类把包转换为概念向量表示形式,然后计算概念向量之间的海明距离,在此基础上计算描述包光滑性的图拉普拉斯矩阵,进而计算包层次的半监督核,最后在多示例学习标准数据集和图像数据集上测试本算法。测试表明本算法有明显的改进效果。     

基于包标记的无线传感器网络溯源定位算法

标记概率计算作为概率包标记技术的关键内容,对算法的收敛性、最弱链、节点负担等方面具有重要影响。为此,分析现有算法的优缺点,结合无线传感器网络(WSN)的分簇结构,提出一种基于包标记的层次式混合概率包标记算法。扩大上下游节点的相对距离差,从而拉大节点标记概率之间的差距,增加上游节点标记的到达概率,在降低节点负担和算法复杂度的同时,提高算法收敛性。分析结果表明,该算法在收敛性、最弱链方面优于基本包标记法,在节点计算与存储负担方面优于自适应包标记法,可实现WSN资源约束条件下的整体优化。     

一种分块包标记的IP追踪方案

DDoS攻击以其高发性、高破坏力和难以防范的特点,近年来成为互联网的主要安全威胁之一．研究者们提出了多种对抗DDoS攻击的方法．：乓中,Savage等人提出的概率包标记方案以其易于实施、消耗资源小等优点,引起人们的重视．然而概率包标记方案存在两个明显缺陷：多攻击路径重构时的高误报率和高计算复杂度．在概率包标记的基础上,提出了一种分块包标记方案,该方案与概率包标记方案相比具有较低的误报率和较低的计算复杂度,因而具有更高的实际应用意义．     

一种Web软件安全漏洞分类方法

研究了环境错误与状态错误引发Web应用软件安全问题的途径,在此基础上提出了一种用于进行Web应用软件安全漏洞分类的层次分析模型。使用该模型对CVE漏洞数据库中抽取的Web软件安全漏洞进行了分类,并与使用EAI模型分类的结果做了对比。评估结果表明,该模型具备良好的漏洞分类能力,适用于指导Web应用软件的安全测试和安全防御工作。     

IC卡系统的安全技术及其应用实例

讨论了IC卡及其应用系统的安全技术,从底层硬件、操作系统到上层应用软件三个层次进行了分析.通过一个自动售货机IC卡消费系统的安全性设计方案着重说明了上层应用软件的安全性设计.     

半监督多示例核

在多示例学习中引入利用未标记示例的机制,能降低训练的成本并提高学习器的泛化能力。当前半监督多示例学习算法大部分是基于对包中的每一个示例进行标记,把多示例学习转化为一个单示例半监督学习问题。考虑到包的类标记由包中示例及包的结构决定,提出一种直接在包层次上进行半监督学习的多示例学习算法。通过定义多示例核,利用所有包(有标记和未标记)计算包层次的图拉普拉斯矩阵,作为优化目标中的光滑性惩罚项。在多示例核所张成的RKHS空间中寻找最优解被归结为确定一个经过未标记数据修改的多示例核函数,它能直接用在经典的核学习方法上。在实验数据集上对算法进行了测试,并和已有的算法进行了比较。实验结果表明,基于半监督多示例核的算法能够使用更少量的训练数据而达到与监督学习算法同样的精度,在有标记数据集相同的情况下利用未标记数据能有效地提高学习器的泛化能力。     

基于动态概率包标记的IP追踪方法

目前多数概率包标记都存在遗失标记信息、重构困难、准确率低等现象。针对该问题,提出一种基于动态概率包标记的IP追踪方法。采用动态标记概率代替原有的固定标记概率用于判断是否对数据包进行标记,应用更合适的概率对其标记。实验结果表明,该方法能解决标记覆盖问题,降低样本依赖性,提高准确率。     

基于可变概率包标记的对等网DDoS攻击防御

DDoS攻击是对等网络所面临的主要安全威胁,针对已有的概率包标记算法计算量繁重、无法识别虚假标记数据包欺骗等方面的缺陷,提出一种可变概率包标记算法。通过采用可变概率标记方法及在路由器中记录IP地址发送状态,使方案具有能够追踪大规模拒绝服务攻击、识别和排除攻击者虚假标记信息、大大降低受害者重构路径时需接收包数量的优点,从而达到有效防御DDoS的目的。和同类方法相比,该方案具有较强的实用性。     

跨域的混合包标记编码方案

在自适应概率包标记的基础上提出了一种基于跨域的自适应概率包标记编码方案。模拟实验表明：采用该方法在重构路径时,所需要的包个数低于同类型的自适应概率包标记方案和高级包标记方案。     

重叠哈希分片的概率包标记方法

针对压缩边分片采样算法复杂度和重构路径误报率过高的问题,提出一种改进的压缩边分片采样概率包标记方法,即重叠哈希分片(OHF)的概率包标记方法。该方法在不增加包标记位的前提下,通过构造相邻的IP哈希分片之间的4位哈希关系,降低重构算法复杂度,同时改善边采样误报率。在NS2环境下的仿真实验表明了OHF方法的有效性。     

Hierarchical structures of optimization packages

Conclusions The expanding operational potential of application packages (interactive and multiprocessing disciplines, application in systems with complex environment, processing of large volumes of data) necessitated a transition from the one-level to a hierarchical package model, in line with the increasing complexity of the package structure.Not all the levels are necessarily present in the design of specific packages. For example, packages executing in the batch mode without multiprocessing and user-initiated dialog do not need the process synchronization level, whereas the top level-the process level-is realized by a single process (in the operating system sense) with the structure described in [1–3]. Packages whose programs always fit into the main memory do not need the data management level, i.e., the cluster is realized by an abstract application module. The application program level is missing in those packages where the application programs are prepared in advance, rather than being generated in run time.The proposed structure is not restricted to optimization packages: it may be used to typify other classes of method-oriented packages. Structure-driven package design ensures that the package has the required properties, makes it possible to implement the software-engineering approach to the design process, avoids gross design errors, and simplifies package adaptation to different environments. Moreover, the hierarchical package structure allows a more technological approach to the development process, as it leads to more effective application of the methods of hierarchical, modular, and structured programming.Translated from Kibernetika, No. 2, pp. 35–39, March–April, 1982.     

The Package Blueprint: Visually analyzing and quantifying packages dependencies

Large object-oriented applications are structured over many packages. Packages are important but complex structural entities that are difficult to understand since they act as containers of classes, which can have many dependencies with other classes spread over multiple packages. However to be able to take decisions (e.g. refactoring and/or assessment decisions), maintainers face the challenges of managing (sorting, grouping) the massive amount of dependencies between classes spread over multiple packages. To help maintainers, there is a need for at the same time understanding, and quantifying, dependencies between classes as well as understanding how packages as containers of such classes depend on each other.In this paper, we present a visualization, named Package Blueprint, that reveals in detail package internal structure, as well as the dependencies between an observed package and its neighbors, at both package and class levels. Package blueprint aims at assisting maintainers in understanding package structure and dependencies, in particular when they focus on few packages and want to take refactoring decisions and/or to assess the structure of those packages. A package blueprint is a space filling matrix-based visualization, using two placement strategies that are enclosure and adjacency. Package blueprint is structured around the notion of surfaces that group classes and their dependencies by their packages (i.e., enclosure placement); whilst surfaces are placed next to their parent node which is the package under-analysis (i.e., adjacency placement). We present two views: one stressing how an observed package depends upon the rest of the system and another stressing how the system depends upon that package.To evaluate the contribution of package blueprint for understanding packages we performed an exploratory user study comparing package blueprint with an advanced IDE. The results show that users of package blueprint are faster in analyzing and assessing package structure. The results are proved statically significant and they show that package blueprint considerably improves the experience of standard browser users.     

Package Coupling Measurement in Object-Oriented Software

The grouping of correlated classes into a package helps in better organization of modern object-oriented software. The quality of such packages needs to be measured so as to estimate their utilization. In this paper, new package coupling metrics are proposed, which also take into consideration the hierarchical structure of packages and direction of connections among package elements. The proposed measures have been validated theoretically as well as empirically using 18 packages taken from two open source software systems. The results obtained from this study show strong correlation between package coupling and understandability of the package which suggests that proposed metrics could be further used to represent other external software quality factors.     

DISPRO: A discrete programming package

Conclusions The DISPRO package is open for modification and further development. Its modular structure allows expansion of the source language, incorporation of new system and application modules, realization in the current version of an interface with DBMS and other application packages (e.g., report generator, matrix generator), synthesis of the package with PL/1 and FORTRAN IV programming systems.The first version of DISPRO released in 1980 has successfully passed the requisite acceptance tests and is now officially part of the optimization packages supported by ES series computers. As outlined in this article, the package has tremendous possibilities for solving a wide range of discrete optimization problems. So far, certain classes of discrete programming problems could be solved by LP ASU [31], VEKTOR-1, the Z-system [58], and TsP [31] application packages. In addition, some packages have been developed in recent years for mathematical programming and operations research (DISPLAN, an interactive planning system [60]; PTP, optimization of transportation problems [58]; PMP, separable and parametric linear programming; DILOS, interactive system for unconstrained optimization, nonlinear programming, and optimal control; ORBITAL', unconstrained optimization and approximation [61]; NDO, nondifferentiable and stochastic optimization [62]; and other less known packages reviewed, in particular, in [58].New optimization packages are currently being developed in response to increased demands for quality, efficiency, and applicability in various MIS and ADPS. The next version of the DISPRO package is being designed on the basis of the appropriate principles and requirements for modern method-oriented packages, including accumulation and analysis of package performance data (these data may be used to improve the package software and structure), large dimensionality of the relevant problems, operating reliability, commercial development of packages, and their usability in integrated data processing systems.In conclusion, DISPRO was developed by the concerted effort of a large team. In particular, we should mention the contributions of Yu. M. Ermol'ev, V. L. Volkovich, A. I. Kuksa, Yu. Yu. Chervak, N. S. Podgorodetskaya, E. S. Karpinka, V. M. Sementsova, V. I. Artemenko, and other members of the team.Translated from Kibernetika, No. 3, pp. 117–137, May–June, 1981.     

基于单片机的CAN_NODE的设计与实现

CAN_NODE实验板是一款功能强大的8位AVR单片机实验板,采用的是基于AVR RISC结构的8位低功耗CMOS微处理器ATmega128。由于其先进的指令集以及单周期指令执行时间,ATmega128的数据吞吐率高达1 MIPS/MHz。板上提供了CAN总线通讯所需要的硬件,按键,LED,USB接口等常用的功能部件,为系统扩展而预留了扩展功能接口,提供了SPI接口和JTAG接口以方便下载和调试。     

Package Fingerprints: A visual summary of package interface usage

ContextObject-oriented languages such as Java, Smalltalk, and C++ structure their programs using packages. Maintainers of large systems need to understand how packages relate to each other, but this task is complex because packages often have multiple clients and play different roles (class container, code ownership, etc.). Several approaches have been proposed, among which the use of cohesion and coupling metrics. Such metrics help identify candidate packages for restructuring; however, they do not help maintainers actually understand the structure and interrelationships between packages.ObjectivesIn this paper, we use pre-attentive processing as the basis for package visualization and see to what extent it could be used in package understanding.MethodWe present the Package Fingerprint, a 2D visualization of the references made to and from a package. The proposed visualization offers a semantically rich, but compact and zoomable views centered on packages. We focus on two views (incoming and outgoing references) that help users understand how the package under analysis is used by the system and how it uses the system.ResultsWe applied these views on four large systems: Squeak, JBoss, Azureus, and ArgoUML. We obtained several interesting results, among which, the identification of a set of recurring visual patterns that help maintainers: (a) more easily identify the role of and the way a package is used within the system (e.g., the package under analysis provides a set of layered services), and (b) detect either problematic situations (e.g., a single package that groups together a large number of basic services) or opportunities for better package restructuring (e.g., removing cyclic dependencies among packages). The visualization generally scaled well and the detection of different patterns was always possible.ConclusionThe proposed visualizations and patterns proved to be useful in understanding and maintaining the different systems we addressed. To generalize to other contexts and systems, a real user study is required.     

Natural language interfaces as expert systems r+or tv nd u strial applicatiqks

A human-machine natural language interface can be useful in converting natural language commands into the functional/procedural instructions required for operating one or the other of the commercially available IE software packages, the same pray the qualified analysts and engineers would have performed it. This paper first gives a review of the state of the art in related research areas and concludes that there is a need for the impetus of this research. The paper also presents the natural language interface ProcessTalk and its architectural design with its distinct modules.ProcessTalk's design ensures its portability between different industries and different software packages.An example application is also given.     

OSCAR集群技术

集群系统是目前最广泛被采用的高性能计算机系统解决方案。安装一个高性能计算集群需要多个节点协同安装和配置，这对于多达几百台计算机节点的集群系统常常是很麻烦的过程。目前最受欢迎的集群系统安装软件包”OSCAR(Open Source Cluster Application Resource)”很好地解决了这个问题。详细介绍了OSCAR的各个功能部件的工作方式和使用方法，并概括了OSCAR集群的安装流程。     

Interactive volume visualization of general polyhedral grids

This paper presents a novel framework for visualizing volumetric data specified on complex polyhedral grids, without the need to perform any kind of a priori tetrahedralization. These grids are composed of polyhedra that often are non-convex and have an arbitrary number of faces, where the faces can be non-planar with an arbitrary number of vertices. The importance of such grids in state-of-the-art simulation packages is increasing rapidly. We propose a very compact, face-based data structure for representing such meshes for visualization, called two-sided face sequence lists (TSFSL), as well as an algorithm for direct GPU-based ray-casting using this representation. The TSFSL data structure is able to represent the entire mesh topology in a 1D TSFSL data array of face records, which facilitates the use of efficient 1D texture accesses for visualization. In order to scale to large data sizes, we employ a mesh decomposition into bricks that can be handled independently, where each brick is then composed of its own TSFSL array. This bricking enables memory savings and performance improvements for large meshes. We illustrate the feasibility of our approach with real-world application results, by visualizing highly complex polyhedral data from commercial state-of-the-art simulation packages.