Integrated Circuit 卡应用系统安全设计研究

针对许多ＩｎｔｅｇｒａｔｅｄＣｉｒｃｕｉｔ（ＩＣ）卡应用系统采用的被动存储型ＩＣ卡一般不能防止非法复制或篡改,对ＩＣ卡应用系统的安全结构进行了分析,基于安全核存在假设和算法安全性假设提出了ＩＣ卡应用系统理论安全模型．并以ＩＣ卡预付费电表系统为例,对攻击者的破译策略进行了分析,讨论了其安全设计策略．     

广东省灵芝、铁皮石斛、西洋参三种食药物质重金属暴露风险评估

目的 分析广东省3种食药物质灵芝、铁皮石斛和西洋参中重金属污染状况及其健康暴露风险。方法 在广东省10个地市采集灵芝及其相关产品（137份）、铁皮石斛及其相关产品（96份）、西洋参及其相关产品（70份）共303份,包括3种物质的鲜品、干制品原料和食品产品,其中广州采集33份、其余9个地市各采集30份。采用电感耦合等离子法进行铅、镉、总汞、总砷的含量测定和分析;根据点评估模型,计算鲜品（按折干率折算）和干制品原料中重金属的平均含量,按照药用和膳食食用两种暴露方式,分别估计3种食药物质的重金属暴露风险。结果 作为药膳食用,暴露量高于药用暴露量,其中灵芝、铁皮石斛、西洋参的镉暴露量占每月可耐受摄入量（PTMI）的8.51%、8.72%和8.56%;总汞的暴露量占PTWI的3.51%、0.91%和1.08%。铅暴露的暴露限值（MOE）分别为11.56、7.14和20.94,总砷暴露的MOE值分别为68.34、102.39和152.28。在考虑膳食暴露途径后,通过3种食药物质引起的重金属暴露风险仍在可接受范围内。结论 广东省居民通过灵芝、铁皮石斛、西洋参的膳食暴露途径引起的铅、镉、总汞、总砷4种重金属的暴露风险较低。     

一个拓扑熵等于∞的非浑沌系统

本文构造了一个离散动力系统(E,σ),其中E是一个可数集。σ:E→E是一个连续映射,满足: 1)σ的拓扑熵是+∞; 2)σ的非游荡集是空集; 3)σ只在E的聚点处有初值敏感性     

中国铜镍工业进展及前景展望

回顾了中国铜镍工业的发展历程 ,展望了 2 1世纪铜镍工业的前景。     

施工管理科学化的论述

施工管理中的施工技术管理、质量管理以及生产要素管理是施工管理的主要方面,处理好三者之间的关系以及解决好三个方面中的任何一方面是在施工中面临的重要问题     

核与辐射事件医学应急管理体系国际比较

介绍了我国核与辐射事件医学应急管理体系的构成,并将之与日本、美国、法国、俄罗斯和加拿大的核与辐射事件医学应急管理体系进行比较,分析其优缺点,同时介绍了WHO和IAEA在核与辐射事件医学应急中的作用,在此基础上提出建立健全我国核与辐射应急医学管理体系、提升医学应急救援能力的建议。     

Orientationability analyses of a special class of the Stewart–Gough parallel manipulators using the unit quaternion representation

This paper addresses the orientation-singularity and orientationability analyses of a special class of the Stewart–Gough parallel manipulators whose moving and base platforms are two similar semi-symmetrical hexagons. Employing a unit quaternion to represent the orientation of the moving platform, an analytical expression representing the singularity locus of this class of parallel manipulators in a six-dimensional Cartesian space is obtained. It shows that for a given orientation, the position-singularity locus is a cubic polynomial expression in the moving platform position parameters, and for a given position, the orientation-singularity locus is an analytical expression but not a polynomial directly with respect to the mobile platform orientation parameters. Further inspection shows that for the special class of parallel manipulators, there must exist a nonsingular orientation void in the orientation space around the orientation origin for each position in the position-workspace. Therefore, a new performance index referred to as orientationability is introduced to describe the orientation capability of the special class of manipulators at a given position. A discretization algorithm is proposed for the computation of the orientationability of the special class of manipulators. Moreover, effects of the design parameters and position parameters on the orientationability are investigated in details. Based on the orientationability performance index, another novel performance index referred to as practical orientationability is presented which represents the practical orientation capability of the manipulator at a given position. The practical orientationability not only can satisfy all the kinematic demands and constraints of such class of manipulators, but also can guarantee that the manipulator is nonsingular.     

Nanoindentation measurement of core–skin interphase viscoelastic properties in a sandwich glass composite

Mechanics of Time-Dependent Materials - Debonding at the core–skin interphase region is one of the primary failure modes in core sandwich composites under shear loads. As a result, the...     

热挤压变形力计算的研究

本文考虑到变形区内切应力非线性分布的特点,采用球坐标系下的平衡微分方程和塑性条件联立求解,得出圆棒热挤压时变形区入口球面上的应力分布方程,然后应用功平衡法导出了圆棒热挤压力的计算公式。     

Fabrication of Cu(In,Ga)Se2 thin films by ion beam sputtering deposition from a quaternary target at different substrate temperatures

Cu(In, Ga)Se₂ (CIGS) thin films were fabricated by ion beam sputtering deposition from a single quaternary target at different substrate temperatures (T _sub). The thin films were characterized with X-ray diffractometry, scanning electron microscopy, energy-dispersive X-ray spectroscopy and four-point probe technique to study the microstructures, surface morphology, composition and electrical properties, respectively. The results show that the films grown above 400?°C are of chalcopyrite structure. Cu(In_0.7Ga_0.3)Se₂ thin film was obtained when T _sub is 550?°C. The Cu and Se atomic percentage when T _sub is above 500?°C is higher than when T _sub is below 500?°C. With the increase in T _sub, the surfaces morphology of the films is denser and the resistivity of the films decreases.