基于Windows 2000 Advanced Server部署补丁服务器

该文通过部署补丁服务器的方式将旧服务器变废为宝,实现了内网补丁自动更新,既节省了资源又有效地保障了内网安全。     

基于URL的内网服务器监管系统研究

分析了内网开放Web服务后所引发的安全问题及其产生的原因,提出了基于URL对内网服务器实施监管的方案。系统采用旁路方式对数据包进行截获,从中提取外网访问内网的URL,并对其进行过滤、分析,从而实现对内网服务器的监控。结合校园网的实际情况,给出了该方案的具体架构和实现方法。     

基于NAT的UDP流媒体服务端到端解决方案

UDP流媒体服务器如何穿透内网满足客户端点播是一个重要的问题。UDP流媒体服务器发送数据之前需要知道发送目的地址(包括IP地址和端口号),而通过代理服务器点播的内网用户无法告知流媒体服务器。该文针对流媒体服务器 ClearServer,提出了一种ClearNat地址映射方法,通过提供NAT地址和端口、内网地址与端口的映射,使ClearServer发送数据到客户端。结果表明,该方法计算复杂度小,支持内网“大并发用户”,对ClearServer主体程序没有影响。     

内网服务器特点分析及安全策略

内网服务器因为其不被互联网大众访问,所以具有用户群相对稳定,安全软件趋同,访问峰值高和维护方便等特点,针对这些特点,可以采取对应的系统安全措施,保障内网服务器的正常运行和企业数据的准确安全。     

局域网中构造补丁服务器

在局域网中构造一台补丁服务器就可以使网络内的客户机定期进行自动补丁升级了。目前有很大一部分的病毒是利用windows操作系统的漏洞来攻击计算机的,微软会不定期地发布修复系统漏洞的补丁,但很多用户苦于没有一个有效的手段对局域网内的众多机器及时进行补丁升级,以致造成重大损失。在局域网中构造一台补丁服务器就可以使网络内的客户机aspx?FamilyId=A7AA96E4-6E41-4F54-972C-AE66A4E4BF6C＆displaylang=en下载软件,安装过程中选择安装英文版本,其他参数使用默认设置即可。安装完成后在管理窗口左栏中点击"OtherOptions"菜单下的"SetOptions"选项,就可以对服务器的基本参数进行设置。     

内网FTP服务器如何连接外网

我在局域网服务器上建立了FTP服务，想让Internet中的计算机也能访问内网的FTP服务器，应该怎样设置才行？     

Linux中配置虚拟专网

本单位有着丰富的内网资源,比如内网的文件服务器、财务工资查询、人事查询,这些服务都只能在本单位内部的电脑上才能访问。同时,本单位的官网管理入口,出于安全的考虑,开启的是8081端口和8082端口,这些在公网上也是禁止访问的,因此当有紧急事件,需要在家或者出差的异地访问本单位的内网服务时,就需要一台提供虚拟专用网络接入的服务器,简称VPN服务器。本文介绍利用Linux操作系统和x12tpd开源软件配置自己的虚拟专用网络服务器的方法。     

服务器安全管理配置技术研究

文章从分布式控制、执行补丁、基于网闸的Web服务器的恢复机制、防火墙、RAS、权限配置、日常管理、制度建设等方面探讨了服务器安全管理的实践经验,提出了解决服务器安全的思路及方法,对网络的规划设计和安全管理有一定的实用价值.     

内网也建Internet服务器

大家都知道，在局域网中架设的WEB服务器．外网(Internet)中的用户是访问不到的，关键是外网通过内网时，其请求被网关过滤掉了。不过如果利用某些工具软件，来突破这种网关的封锁，完全有能力建立一个外网可以访问的内网Internet服务器。     

三大技巧实现Windows服务器高效管理

一、拒绝服务器重新启动 一般情况下,在Windows 2003 Server系统中安装完补丁程序后．系统总会提示要重新启动一下服务器。可是许多朋友往往无法容忍Windows 2003 Server服务器“慢吞吞”的启动操作,于是希望打完安全补丁之后服务器不再重新启动。其实,Windows 2003 Server服务器是否会重新启动,跟当前的系统补丁特性有一定的关系。对于那些强制需要系统启动的安全补丁。一般是无法让服务器拒绝的;     

Conversion method and system

In the classical conversion method, the light that passes the medium is converted to the photosignal. Then, it is amplified by an amplifier having linear characteristics. Considering the amplitude of the amplified signal, the measured parameter is determined. In the proposed conversion method, the intensity of the reference light that falls on the medium is inversely modulated with respect to the absorption function. The intensity of the light used for the measurement is kept constant. The intensity modulated reference light and the measurement light, which are in inverse phases, pass through the medium subsequently. Then, they are detected by a photodetector. At the output of the photodetector, the phase changing instant of the obtained signal and the duration between the starting instant of the reference light and the phase changing instant are determined. Considering this duration, the value of the measured parameter is determined. The proposed conversion method linearizes the conversion phenomenon. The photodetector does only detect the instant at which the reference light and the measurement light are similar. The photodetector operates as an indicator. The measured parameter is converted to the pulse duration or the number of pulses. The value of the measured parameter can be directly obtained at the output of the photodetector. The comparison and the mathematical operations are directly achieved on lights. Analysis of the proposed method and application examples are given in the paper.     

Numerical and experimental study of the virtual quadrupedal walking robot-semiquad

SemiQuad is a prototyped walking robot with a platform and two double-link legs. Thus, it is a five-link mechanism. The front leg models identical motions of two quadruped's front legs, the back leg models identical motions of two quadruped's back legs. The legs have passive (uncontrolled) feet that extend in the frontal plane. Due to this the robot is stable in the frontal plane. This robot can be viewed as a "virtual" quadruped. Four DC motors drive the mechanism. Its control system comprises a computer, hardware servo-systems and power amplifiers. The locomotion of the prototype is planar curvet gait. In the double support our prototype is statically stable and over actuated. In the single support it is unstable and under actuated system. There is no flight phase. We describe here the scheme of the mechanism, the characteristics of the drives and the control strategy. The dynamic model of the planar walking is recalled for the double, single support phases and for the impact instant. An intuitive control strategy is detailed. The designed control strategy overcomes the difficulties appeared due to unstable and under actuated motion in the single support.Due to the control algorithm the walking regime consists of the alternating different phases. The sequence of these phases is the following. A double support phase begins. A fast bend and unbend of the front leg allows a lift-off of the front leg. During the single support on the back leg the distance between the two leg tips increases. Then an impact occurs and a new double support phase begins. A fast bend and unbend of the back leg allows the lift-off of the back leg. During the single support on the front leg the distance between the two leg tips decreases to form a cyclic walking gait.The experiments give results that are close to those of the simulation.Funding for SemiQuad was primarily provided by the CNRS and the region Pays de La Loire.     

Designing the rule classification with oversampling approach with high accuracy for imbalanced data in semiconductor production lines

The product quality is the major factor for enhancing the production ability and competitiveness. Decreasing the cost and increasing production capacity are common approaches to realize the enhancement of the product quality. The production managers apply various multimedia data to evaluate the product quality. For example, capturing the stamping sound to evaluate the correct cutting and taking the component image to measure the chip positions are common heterogeneous multimedia data that are applied to manufacturing. However, the production managers prefer to minimize the number of defective products, e. g. the secondary operation and fixing the product tolerance in the assembly stage, to fitting the production target. Therefore, contrasting the defective product identification procedure with high accuracy becomes a challenge due to the decrease of the number of the defective products. In this paper, we propose the Rule Classification with Oversampling (RCOS) approach to provide the high accuracy with few defective products. The proposed RCOS includes the oversampling technique and the rule classification approach to emphasize the properties of the defective products and provide the precise classes. Given few defective products, capturing the properties of the failure is difficult. The RCOS considers the revised Synthetic Minority Over-Sampling Technique (SMOTE) to highlight the failure properties, and then the rule model is considered to extract the root cause of the defective products. We implement the proposed RCOS in the semiconductor production line. From the experiment results, the proposed RCOS provide about at most 98% in accuracy, and the comparison shows that the results have been improved in common criteria e. g. the true-positive rate, G mean, F1 score, and False Alarm Rate. Therefore, the proposed RCOS provides high practicality for the implementation consideration.

     

一种基于二维可逆映射的图像加密算法

提出了二维可逆映射在图像加密中的应用.可以通过置乱图像像素位置实现图像加密.二维可逆映射可以高效地实现图像像素置乱.二维可逆映射由压缩拉伸和折叠两个子映射组成.压缩拉伸映射,使原始图像变换成线,折叠映射使线变换成图.所有可逆映射构成了可逆映射集合.经过扩散处理改变像素值,实现图像加密.二维可逆映射的引入扩大了密钥空间,并增强了对密钥变化的敏感度.新的加密方法提高了加密图像的安全性且加快了加密速度.仿真验证了二维可逆映射图像加密算法的有效性.     

FB-CS模型的两层嵌套机动目标跟踪算法

针对转弯机动目标,提出了一种两层模型嵌套的跟踪算法.算法的内层模型由基于函数的“当前”统计(Function based current statistic,FB-CS)模型构成,该模型在“当前”统计(Current statistic,CS)模型的基础上,通过加权一个以新息方差之迹为参数的活化函数,对加速度方差和机动频率进行自适应处理,再针对目标的速度方向角进行滤波,将获得的角速度估计值作为外层的输入;外层模型由曲线模型构成,其方向角度、角速度和角加速度由内层模型提供.由于既准确估计目标的角速度,又设计了合理的运动模型,算法显著提高了转弯机动目标的跟踪精度.仿真实验验证了算法的有效性.     

Passive mixing of co-flowing slugs in grooved microchannels

The anisotropic grooves in a microchannel induce spiral circulation around the flow axis. The stretch and fold of the streams result in a passive mixing. This article describes the effectiveness of induced crossflow, arising from the grooves, placed at the floor of the microchannel. The results from numerical simulation show the extent of local mixing achieved at various positions around the groove. The emphasis here is to understand the mixing when the two streams enter the channel, and displace air while flowing alongside each other. Microchannels with slanted grooves and staggered herringbone type grooves are considered here. The FLUENT 6.2 software and the Open FOAM software were used for the simulation. The latter was primarily utilized for tracking of the interface when a liquid slug displaced air from the micromixer. At a Reynold’s number of about 1.0, low velocity pockets could be identified near the two ends of the ridges. These pockets did not support crossflow and mixing. The herringbone type micromixer was found to have the best mixing effectiveness, when the advection dominates mixing. This advantage is mostly lost at the higher values of diffusivity, as a crossflow became less important for mixing. These observations were made when one of the streams is 1.5 times more viscous than the other, and the mixture-rule governed the viscosity of the mixed stream. When the liquid front enters the microchannel for the first time, the front had to displace air from the channel. At first, the upper part of the channel was swept. This was immediately followed by the sweeping of the groove-part in the floor. Higher hydraulic resistance in the grooves resulted in this non-uniform movement of the front. The co-flow of streams could either be continuous over the entire length of the channel, or in the form of slugs that maintained an interface with air. At a particular position in the channel, the extents of mixing were compared for the two modes of co-flow. The extent of mixing was found smaller in the slug, next to the interface with air. Lack of axial dispersion with preceding liquid stream seems to be the reason for this trend.     

粗糙集理论在故障诊断中的问题分析

粗糙集理论能对系统中的冗余信息进行约简,但其处理过程完全基于样本集,样本集的完备性对其处理结果有直接影响.对粗糙集理论及其在故障诊断中属性约简存在的问题进行了分析,通过实例证明了在故障样本集不完备的情况下,利用粗糙集进行的属性约简会由于新故障样本的引入而导致前后约简结果的不一致,从而影响诊断的准确性;指出了该问题产生的关键原因及解决的办法,并给出了相关的实现算法,以提高系统的故障诊断自适应性.     

Sensor system of a small biped entertainment robot

SDR-4X II is the latest prototype model of a small biped entertainment robot. It is the improved model of SDR-4X. In this paper we report on the sensing system of this robot, which is important and essential for a small biped entertainment robot which will be used in the home environment. One technology is the design of the motion sensing system, i.e. the inclination sensor system and the force sensor system which obtains the inclination of the trunk and the foot with force. Another technology is the real-world sensing system. One aspect is the touch sensing system. The robot is used in a normal home environment, so we should strongly consider the safety aspects for human. Another is the vision sensor system. The configuration and the distance image acquisition are explained. Next is the audio sensor system which obtains the sound and the voice information. The hardware system and the direction recognition are explained. These sensing systems are the key to making the biped robot walking and dynamic motion highly stable, and understanding the real-world around the robot.     

机器人足球比赛截球策略设计

在机器人世界杯足球锦标赛(TheRobotWorldCup,简称RoboCup)中,截球效率直接影响到比赛的结果。通过足球截球模型,建立方程,从而求出截球位置。解方程的根是提高截球效率的关键,本文采用高效的弦割法来快速计算方程的根。试验发现方程曲线的变化对弦割法解方程根的效率有很大影响,曲线的形状直接影响了弦割法的收敛速度。为加速收敛性,对弦割法进行了优化。最后与优化前的弦割法以及二分法进行了比较,结果表明优化后整体性更为高效,很好地满足了比赛的要求。     

Greedy algorithms for eigenvalue optimization problems in shape design of two-density inhomogeneous materials

This paper studies the eigenvalue optimization problems in the shape design of the two-density inhomogeneous materials. Two types of greedy algorithms are proposed to solve three optimization problems in finite element discretization. In the first type, the whole domain is initialized by one density. For each problem of the eigenvalue optimizations, we define a measurement of the element, which is the criterion to determine the ‘best’ element. We change the density of the ‘best’ element to the other density. Then the algorithm repeats the procedure until the area constraint is satisfied. In the second type, the algorithm begins with the density distribution satisfying the area constraint. Also, according to the measurement of the element, the algorithm finds a pair of the ‘best’ elements and exchanges their densities between each other. Furthermore, the accelerating greedy algorithms are proposed to speed up both two types. Three numerical examples are provided to illustrate the results.