一种基于Web漏洞威胁模型的网站安全分析技术

网站日益受到黑客的青睐,针对Web应用程序的攻击事例屡见不鲜。如何全面、准确地分析网站面临的最大威胁成为专业信息安全公司和网站管理员的不可回避的难题。本论文借鉴攻击图的基本思想设计了漏洞威胁测试模型(VTTM),并以SQL注入漏洞为例对其进行建模,并利用两种算法分别计算了网站的最大威胁值及最优测试序列。     

Economic modeling of board test strategies

A long and deep recession, coupled with continuous competitive pressure to reduce costs, is forcing many companies to review their test strategies. Testing costs have become a more significant proportion of the overall manufacturing cost even though manufacturing yields have increased dramatically over the past ten or twelve years. This causes attention to be focused on testing costs as a key source of cost reduction. The increased use of DFT and the integration of design and test are very positive moves towards controlling testing costs but other methods employed can often backfire. The increased use of low priced testers is one such method. The pressure to reduce costs, higher process yields and exhortations that testing adds no value can lead the test engineering manager to take the cheap route. In reality this can often turn out to be an expensive decision. The only way to avoid expensive mistakes is to perform an economic analysis of the alternative courses of action. In most cases this is done, but not always in the right manner or with the necessary amount of detail to make the comparisons meaningful. This article discusses the need for effective cost analysis of test strategies and highlights some of the pitfalls.     

标准测试存取口与边界扫描结构在印制板级与系统级实现的探讨

本文探讨中国电子行业标准“标准可测性总线”第一部分“标准测试存取口与边界扫描结构”在印制板级与系统级的实现问题。阐述了不要针床夹具借助边界扫描测试印制板上器件间互连的方法,综述了美国相应标准ＩＥＥＥ Ｓｔｄ １１４９．１公布前后提出和试行在印制板级和实验级实现的若干方法和方案,包括采用符合与不符合该标准的两种器件的混合型板和系统。初步探讨了实践中国电子行业标准“标准测试存取口与边界扫描结构”和开发     

白蚁提取液急性毒性及致突变性研究

本文采用大,小鼠急性经口毒性试验、Ａｍｅｓ试验、小鼠骨髓细胞微核试验及小鼠精子畸变试验对白蚁提取液的毒理学安全性进行了研究,结果表明,白蚁提取液大,小鼠急性经口ＬＤ５０均大于１０ｇ／ｋｇ体重,属“实际无毒”：体内（包括体细胞和生殖细胞）、体外致突变性试验系统均未检出其致突性。     

Comments on “Aliasing Properties of Circular MISRs”

The analysis of aliasing probability presented in a recent article, Aliasing Properties of Circular MISRs [1], is based on an error model that cannot adequately represent real circuits. We show why conclusions presented in [1] should not be used in practice, substantiating our claim with experimental results.This work was supported in part by grants from the Natural Sciences and Engineering Research Council of Canada and in part by the British Columbia Advanced Systems Institute     

A study on improving shielding performance of shielded cable

With the developments in power electronics equipment, the electromagnetic environment has become severe for electronic equipment. In the smart facility field, the stable operation of electronic devices is indispensable, and noise countermeasures must be improved. To suppress intrusive noise from cables, shielded cables are used in many cases. However, electromagnetic induction cannot be suppressed when the shield is grounded at one end, and when grounding both ends of the shield, current flows through the shield creating intrusive noise in the cable. That is, even if a shielded cable is used, a sufficient effect cannot be obtained. Therefore, as a countermeasure, this study prototypes and evaluates cables that combine double shielded cables with magnetic cores. Evaluations conducted using the copper pipe method, triaxial method, and impulse test confirm that the shielded performance improved by 10–30 dB compared with the conventional shielded cable.     

基于转移阻抗模型的功率回路和信号回路间串扰建模与试验验证

由于列车和船舶上的空间有限,互连非屏蔽线缆的空间非常小,导致非屏蔽线缆之间存在严重的串扰问题。其中功率回路对信号回路的串扰会严重影响信号的质量和系统的正常运行,因此有必要估计功率回路中共模和差模电磁干扰对信号回路的影响,为此提出了一种可扩展的级联多端口网络模型,可对线缆间共模和差模串扰进行精准建模,准确估计出功率回路对信号回路的影响。最后,搭建了试验台架进行验证,实验结果验证了该方法的有效性。     

Incombustible Polymer Electrolyte Boosting Safety of Solid-State Lithium Batteries: A Review

Lithium-ion batteries with their portability, high energy density, and reusability are frequently used in today's world. Under extreme conditions, lithium-ion batteries leak, burn, and even explode. Therefore, improving the safety of lithium-ion batteries has become a focus of attention. Researchers believe using a solid electrolyte instead of a liquid one can solve the lithium battery safety issue. Due to the low price, good processability and high safety of the solid polymer electrolytes, increasing attention have been paid to them. However, polymer electrolytes can also decompose and burn under extreme conditions. Moreover, lithium dendrites are formed continuously due to the uneven charge distribution on the surface of the lithium metal anode. A short circuit caused by a lithium dendrite can cause the battery to thermal runaway. As a result, the safety of polymer solid-state batteries remains a challenge. In this review, the thermal runaway mechanism of the batteries is summarized, and the batteries abuse test standard is introduced. In addition, the recent works on the high-safety polymer electrolytes and the solution strategies of lithium anode problems in polymer batteries are reviewed. Finally, the development direction of safe polymer solid lithium batteries is prospected.     

多路热气流量控制及其在防除冰试验中的应用

流量精确控制是保证结冰风洞热气防除冰试验成功的关键,针对传统调节阀控制存在受下游影响大和多路流量控制耦合的问题,设计了一套多路热气流量控制系统,采用背压阀对各支路流量控制单元入口压力进行精确控制,通过电作动筒改变各支路针阀喉道流通面积,结合临界流文氏管流量计流量测量,实现多路流量解耦控制。试验表明,多路热气流量控制系统可实现多路流量解耦控制,调节速度快,10 s左右即可达到目标流量,控制精度高,稳定后最大相对误差小于0.6%,该系统可为我国后续飞行器防除冰试验系统验证与适航审定提供有力支撑。     

自动驾驶交叉路口测试场景建模及验证方法

自动驾驶汽车在缓解交通拥堵和消除交通事故方面发挥着重要作用.为了保证自动驾驶系统的安全性和可靠性,在自动驾驶汽车部署到公共道路之前,必须进行全面的测试.现有的测试场景数据大多来源于交通事故和交通违法场景,而且自动驾驶系统最基本的安全需求就是遵守交通法规,这充分体现了自动驾驶汽车遵守交通规则的重要性.然而,目前严重缺少针对交通法规构建的自动驾驶测试场景.因此,本文从交通法规出发,根据自动驾驶系统安全需求,提出交叉路口测试场景的Petri网建模及形式化验证方法.首先,依据自动驾驶测试场景对交规进行分类,提取适合自动驾驶汽车的文本交规,并进行半形式化表征.其次,以覆盖道路交通安全法规以及测试场景功能测试规程为目标,融合交叉路口场景要素的交互行为,合理选择并组合测试场景要素,布设交叉路口测试场景.然后,基于交规的测试场景被建模为一个Petri网,其中,库所描述自动驾驶汽车的状态,变迁表示状态的触发条件,并选择时钟约束规范语言（CCSL）作为中间语义语言,将Petri网转换为一个可进行形式化验证的中间语义模型,提出具体的转换方法.最后,通过Tina软件分析验证交规场景模型的活性、有界性和可达性,结果表明所建模型的正确性,并基于SMT的分析工具MyCCSL来分析CCSL约束,采用LTL公式以形式化方法验证交规场景模型的一致性.