Unisys实现开放源代码突破

Unisys日前宣布其Unisys开放、安全集成解决方案(OASIS)在开放源代码功能方面实现了重大突破。该解决方案为一套集成、经过认证的软件,专门设计用于基于开放标准并被Unisys全球服务与垂直行业解决方案功能全面支持的企业级计算。通过技术与服务的完美结合,Unisys开放源代码解决方案可提供一个综合的环境,使客户能够利用开放源代码软件的经济效益,从而获得企业计算的最大优势。Unisys OASIS及其服务能够帮助客户采用科学、安全的方式,实现开放源代码解决方案带来的成本、灵活性和安全优势。Unisys OASIS的推出是开放源代码解决方案…     

多用户环境中签名方案的安全性研究

数字签名已经成为网络信息时代身份认证的重要手段之一.为了使数字签名技术得到更广泛应用,研究了数字签名方案在多用户环境中的安全性.众所周知,一个安全的数字签名方案即使在自适应选择明文攻击下存在性伪造在计算上也是不可行的,认为这在多用户环境中是不充分的,为此,将该安全性概念扩充到多用户环境,并通过实例证明了在单用户环境中安全的签名方案施加适当的限制后在多用户环境中同样也是安全的.     

基于USB Key的数字化会议安全身份认证技术

常规的数字化会议安全身份认证技术利用最低有效位（Least Significant Bit,LSB）生成隐藏矩阵,需使用多用户完成解密,导致其信息隐藏容量不足,因此需要基于USBKey设计一种全新的数字化会议安全身份认证技术。以用户的身份认证数据为基础,生成全新的USB Key身份认证密钥,获取身份认证方案的认证权限,从而输出安全认证协议,完成数字化会议安全身份认证。实验结果表明,设计的数字化会议安全认证技术在不同的隐藏信息位数下的信息隐藏容量始终较高,证明该技术的认证效果较好,具有可靠性,有一定的应用价值。     

轻量级RFID双向通信认证协议优化方案

以轻量级RFID双向通信认证的设计与实现为研究目标,针对目前存在的轻量级RFID算法空白,所有权转移问题难以解决,现有协议未经过实际检验等问题,基于ECC算法机制,开展设计研究,取得了轻量级RFID双向通信认证协议的逻辑设计、源代码编写、硬件调试、上位机软件编写、可靠性测试等成果,可直接投入实际运用。文章从现有RFID安全认证协议出发,精心论证,认真分析,确保每一步认证的安全性,实现了授权访问、双向认证、标签匿名性、可用性,有效地保护了标签和数据库双向安全,满足RFID系统的安全需求。     

常见源代码安全漏洞分析与研究

源代码安全作为软件安全最为重要的安全点之一,是软件安全最底层的关键点。文章提出了源代码安全的一些常见的检测指标,结合SQL注入、跨站脚本、路径篡改和空指针4个比较常见的源代码安全漏洞对源代码安全进行了详细的分析研究。文章提出了源代码安全必须规避的一些基本方法,提高了源代码的安全和质量。     

基于802.1x认证与WEP结合使用提高WLAN安全性

论文通过分层安全模型研究了IEEE802.11WLAN安全性协议的性能以及在多用户、拥塞和非拥塞情况下,不同安全机制对安全网络性能的影响,从而论证了在对无线网络性能影响有限的情况下,WEP与802.1x结合使用,采取集中认证和动态密钥管理机制,可以获得比WEP更好的无线网络安全性。     

文档管理手记—PVCS VM在软件项目中的应用实例

在软件系统的开发过程中,开发人员经常会遇到这样的问题: (1)源代码和文档数量急剧增加; (2)经常需要与错综复杂的多用户、多产品的软件版本打交道; (3)开发组成员间源代码的更新和保存记录越来越复杂; (4)产品的多版本导致磁盘空间占有量浩大。     

基于Linux操作系统的安全编程

Linux操作系统对多任务、多用户和网络服务的支持使得Linux的管理和开发人员需要更多地关注安全问题,以避免数据的泄漏和丢失以及应用系统遭受破坏。介绍了ISO安全模型,以及在Linux编程中如何使用系统提供的认证和访问控制服务和如何避免几种最常见的安全性错误。     

旅游信息查询系统安全设计全方案

旅游信息查询系统是国内旅游业第一套实用信息查询系统,其功能多、信息量大,涉及到数据库平台建立、维护和数据加密传递与多用户管理等方面。安全平台包括身份认证、加密传输及数字签名等功能,采用基于动态分组密码算法——DES来实现身份认证以及数据加密传输部分。     

微软扩展共享计划将进一步开放视窗源代码

近日，微软终于正式宣布，将对win－dows操作系统和．NET服务器软件的源代码向包括康柏和Avanade公司在内的通过认证的１５０家公司的系统集成专家开放。这一认证过程，就是微软对被认证者进行各种资质考察，签署“系统集成商源代码协议”（SystemsIntegratorSourceLicensingPro－gram（SISLP））的过程。在该过程中，微软将允许关系最密切的客户与合作伙伴及一些教育和政府机构了解部分软件系统的内部结构。同时，提供了基于Windows的更加稳定和安全可靠的应用解决方案。据悉，这是该公司“共享源代码计划”的一部分，目前该计划在中…     

基于Linux的嵌入式Web服务器设计与应用

阐述了基于Linux的嵌入式Web服务器的硬件软件体系结构,介绍了通用网关接口（CGI）技术的工作原理,利用Boa构建了基于Arm-Linux操作系统的嵌入式Web服务器,提出了交互式用户应用程序的设计方法,并利用通用网关接口成功实现了动态网页的实例。     

基于串口设备的嵌入式Web 服务器系统

随着Internet的迅猛发展和广泛普及,让全部设备接入网络,以Internet为介质实现信息交互成为未来设备网络化的发展趋势.介绍了一种以ARM7系列的微处理器S3C44B0X和RTL8019AS网络接口芯片为主要构件的嵌入式系统,移植了uClinux操作系统、boa软件和CGIC库,实现了串口设备的网络化,用户可以通过Internet访问该系统并通过Web网页与之交互,实现远程实时监控和管理设备,在工业自动化、远程监测等领域有广阔的应用前景.     

动态Web技术在实时监测系统中的实现

文章讨论了如何通过动态Web技术来实现远程数据实时监测。首先提出了系统的设计框架和硬件组成,在系统软件层的关键技术中,分析了uClinux操作系统,选取Boa作为嵌入式WebServer,重点研究了动态Web技术CGI和Flash的实现机理。最后通过编写CGI程序并结合Flash动画实现了动态Web交互功能,解决了数据在浏览器中的实时刷新和动态描绘问题,人机界面更加友好,数据显示更加直观,成功地实现了远程实时监测功能。     

基于WiFi的网络化油井示功图测试系统研究

针对传统采油井示功图仪不能实现远程实时监控的问题,设计实现了一种网络节点示功图测试系统.以S3C2440A微处理器为核心,采用Marvell 88w8686无线WiFi网卡、4路A/D转换器件ADS8341和相关外围器件构成硬件平台.软件系统在嵌入式Linux操作系统下,运用嵌入式Web服务器boa和动态网页技术实现了远程数据的采集和实时监控,对采集到的加速度数据经消噪、两次积分求出位移量,压力数据经过滤波、线性变换求出载荷量,将得到的一个完整冲程数据存入本节点SQLite数据库,以便历史数据的查询和下载.现场测试结果表明,该系统达到了实际应用的要求.     

基于FPGA的多通道模拟量采集/输出PCI板卡的研制

为实现模拟量采集与输出功能的高度集成和提高板卡的性价比,针对目前模拟量采集与输出板卡的研究现状,在对板卡功能及其关键器件进行系统阐述的基础上,以EP3C5E144C8为本地总线控制器,以PCI9054为PCI总线协议芯片,以MAX1270、AD7398为12位A/D转换器与D/A转换器,研制一块同时具有4通道模拟量采集与输出功能的板卡,给出该模块的硬件设计与软件开发(包括基于VC++的板卡测试软件与基于Verilog的板卡时序仿真),并对其通信功能进行测试验证,仿真与测试结果表明其有效性。     

Study of Stratospheric Sudden Warming (SSW) over the tropical and subtropical regions of India using Rayleigh lidar

The Stratospheric Sudden Warming (SSW) is one of the most spectacular phenomena in the atmosphere and has impacts on the Earth’s lower, middle, and upper atmospheres. In this study, two major SSW episodes associated with vortex displacement and vortex splitting that occurred in the years 1998 and 1999, respectively, are investigated for the first time over Mt. Abu using lidar observations. Analyses show that ground-based lidar and satellite observations from the Halogen occultation experiment (HALOE) on board the upper atmospheric research satellite (UARS) can capture the effect of SSW events. Lidar measurements are able to capture SSW warming and its decay very accurately. The impact of SSW is further investigated in the European Centre for Medium-Range Weather Forecasts (ECMWF) Interim-reanalysed potential vorticity. Moreover, a detailed study has been presented to understand the latitudinal variation of SSW warming and the associated mesospheric cooling over the Indian region. The results showed that warming is higher over the northern Indian region (35° N, 77° E) compared with the southern Indian region (5° N, 77° E).     

Configurable chips meld software and hardware

Processors that can be configured by end users promise to combine hardware's speed and efficiency with software's flexibility. Developments in configurable computing increasingly blur the line between hardware and software, a trend that represents a major shift in computing practice. To keep their offerings current and relevant, universities should modify their computer science curricula to better prepare students for this new era. Although hardware design is much more software-oriented now, aspiring computing students still need courses that cover hardware synthesis techniques, codesign methodologies, and module reuse strategies. Students should also experience working in teams. At our institute, we have developed such a new curriculum. By offering several hardware courses at both the elementary and advanced levels, we help students obtain a deeper and broader knowledge of configurable hardware design. Moreover, over the past few years we have invested in the design and construction of several FPGA-based boards for use as teaching platforms. These boards let students gain hands-on experience with technologies they'll use in real-world jobs. For example, using the Labomat board, a three-student team designed and tested a simplified floating-point unit in five three-hour sessions     

Ergonomic evaluation of slide boards used by home care aides to assist client transfers

Home care aides risk musculoskeletal injury because they lift and move clients; the body weight of most adults exceeds the NIOSH recommended limit for lifting. Methods to reduce manual patient lifting in institutional settings are often technically or economically infeasible in home care. Our goal was to identify suitable, safe, low-technology transfer devices for home care use. Sixteen experienced home care aides performed client transfers from wheelchair to bed (upward) and bed to wheelchair (downward) in a simulated home care environment (laboratory), using four different slide boards and by hand without a device. Aides’ hand forces were measured during client transfers; aides also evaluated usability of each board. Hand forces exerted while using slide boards were mostly lower than in manual transfer, and forces were lower in downward versus upward transfers. Aides judged a board with a sliding mechanism easier to use than boards without a sliding mechanism.

Practitioner Summary: This paper provides quantitative biomechanical measurements showing that slide boards reduced the hand forces needed by home care aides to transfer clients from bed to wheel chair and vice versa, compared to manual lifting. Using a semi-quantitative usability survey, aides identified boards with a sliding mechanism easiest to use.     

Recursive approximate solution to time-varying matrix differential Riccati equation: linear and nonlinear systems

An approximate solution is proposed for linear-time-varying (LTV) systems based on Taylor series expansion in a recursive manner. The intention is to present a fast numerical solution with reduced sampling time in computation. The proposed procedure is implemented on finite-horizon linear and nonlinear optimal control problem. Backward integration (BI) is a well known method to give a solution to finite-horizon optimal control problem. The BI performs a two-round solution: first one elicits an optimal gain and the second one completes the answer. It is very important to finish the backward solution promptly lest in practical work, system should not wait for any action. The proposed recursive solution was applied for mathematical examples as well as a manipulator as a representative of complex nonlinear systems, since path planning is a critical subject solved by optimal control in robotics.     

The solitary wave solution of the two-dimensional regularized long-wave equation in fluids and plasmas

This paper investigates the solitary wave solutions of the two-dimensional regularized long-wave equation which is arising in the investigation of the Rossby waves in rotating flows and the drift waves in plasmas. The main idea behind the numerical solution is to use a combination of boundary knot method and the analog equation method. The boundary knot method is a meshless boundary-type radial basis function collocation technique. In contrast with the method of fundamental solution, the boundary knot method uses the non-singular general solution instead of the singular fundamental solution to obtain the homogeneous solution. Similar to method of fundamental solution, the radial basis function is employed to approximate the particular solution via the dual reciprocity principle. In the current paper, we applied the idea of analog equation method. According to the analog equation method, the nonlinear governing operator is replaced by an equivalent nonhomogeneous linear one with known fundamental solution and under the same boundary conditions. Furthermore, in order to show the efficiency and accuracy of the proposed method, the present work is compared with finite difference scheme. The new method is analyzed for the local truncation error and the conservation properties. The results of several numerical experiments are given for both the single and double-soliton waves.