向性

The security of PKI system itself is especially emphasized during the system design and implementation process, which is in accordance with the pervasive characteristic of PKI. Second, the concept of a Trusted Key Management Center is introduced for the first time. This technology greatly strengthens key management practices and allows for smooth transition from PKI to Key Management Infrastructure. Third, certificate status mechanisms are investigated in depth, and a certificate revocation performance simulation system is devised. All these work will provide guides to practice and employment of PKI applications. Based on time constraints, a new taxonomy for authenticated dictionaries is proposed. Fourth, formal analysis ofOCSP protocol is carried out; then an efficient and scalable OCSP system is developed. Fifth, the special requirements caused by the working environments of Wireless PKI are analyzed. Based on communicative hashing and dynamic Merkle hash tree, an efficient certificate status validation method suitable for WPKI is presented. Sixth, one important kind of fair exchange protocols is studied, and a new CEMBS based on RSA cryptosystem is proposed. Afterwards, a novel fair exchange protocol totally based on RSA signature scheme is devised.

在系统设计和实现的过程中，考虑到PKI作为普适性安全基础平台的特点，特别强调PKI系统自身的安全性；第二，首次在PKI系统的设计中提出了"可信密钥管理中心"的概念，这一独特设计大大地强化了密钥管理功能的实施，为PKI向密钥管理基础设施的平滑过渡提供了良好的技术准备；第三，对证书状态验证机制进行了深入研究，设计了证书状态模拟系统，以指导PKI系统和应用的部署和实施；在此基础上，基于时间约束首次给出了认证字典的一种新的分类方法；第四，对OCSP协议进行了形式化分析，设计和实现了一种高效、可扩展的OCSP系统；第五，分析了WPKI工作环境对设计安全基础平台提出的特殊要求，结合无线移动设备的具体特点，基于可交换杂凑函数和动态Merkle杂凑树设计出了一种适用于WPKI环境的高效证书状态查询机制；第六，对一类公平交换协议进行了深入的研究，从设计公平交换协议的密码基础结构出发，提出了一种新型的基于RSA密码体制的高效CEMBS；在此工作的基础上，设计了一种基于RSA密码体制的最优化公平交换协议。

The security of PKI system itself is especially emphasized during the system design and implementation process, which is in accordance with the pervasive characteristic of PKI. Second, the concept of a Trusted Key Management Center is introduced for the first time. This technology greatly strengthens key management practices and allows for smooth transition from PKI to Key Management Infrastructure . Third, certificate status mechanisms are investigated in depth, and a certificate revocation performance simulation system is devised. All these work will provide guides to practice and employment of PKI applications. Based on time constraints, a new taxonomy for authenticated dictionaries is proposed. Fourth, formal analysis of OCSP protocol is carried out; then an efficient and scalable OCSP system is developed. Fifth, the special requirements caused by the working environments of Wireless PKI are analyzed. Based on communicative hashing and dynamic Merkle hash tree, an efficient certificate status validation method suitable for WPKI is presented. Sixth, one important kind of fair exchange protocols is studied, and a new CEMBS based on RSA cryptosystem is proposed. Afterwards, a novel fair exchange protocol totally based on RSA signature scheme is devised.

在系统设计和实现的过程中，考虑到PKI作为普适性安全基础平台的特点，特别强调PKI系统自身的安全性；第二，首次在PKI系统的设计中提出了"可信密钥管理中心"的概念，这一独特设计大大地强化了密钥管理功能的实施，为PKI向密钥管理基础设施的平滑过渡提供了良好的技术准备；第三，对证书状态验证机制进行了深入研究，设计了证书状态模拟系统，以指导PKI系统和应用的部署和实施；在此基础上，基于时间约束首次给出了认证字典的一种新的分类方法；第四，对OCSP协议进行了形式化分析，设计和实现了一种高效、可扩展的OCSP系统；第五，分析了WPKI工作环境对设计安全基础平台提出的特殊要求，结合无线移动设备的具体特点，基于可交换杂凑函数和动态Merkle杂凑树设计出了一种适用于WPKI环境的高效证书状态查询机制；第六，对一类公平交换协议进行了深入的研究，从设计公平交换协议的密码基础结构出发，提出了一种新型的基于RSA密码体制的高效CEMBS；在此工作的基础上，设计了一种基于RSA密码体制的最优化公平交换协议。

Mesenchymal stem cells are multipotent stem cell, which can differentiate to the cells derived of mesoderm.

间充质干细胞是一类具有多能性的干细胞，在适宜条件下可以向多种中胚层来源的组织细胞分化。

Methods Focal cerebral ischemia and reperfusion model in male adult SD rats was established by occluding the right middle artery with 40 nylon thread blood flow blocked for 90 minutes and then reperfusion for 1 day, 7 days and 14 days.One microliter MK801 (5mmol/L and NBQX (50mmol/L) were respectively injected into the cerebral ischemic area of SD rats under stereodirectional instrument right after ischemia.

以线栓法制作成年SD大鼠局灶性脑缺血再灌注模型(阻塞90min再灌注1d、7d和14d)，分别向其大脑皮质缺血区立体定向注射5mmol/L 的MK801和50 mmol/L的NBQX各1μl，用免疫荧光组织化学法检测脑缺血再灌注后成年大鼠早期大脑梗死中心区、梗死周边区和缺血对侧NG2和O4阳性细胞数量。

The gold-bearing metamorphic fluid migrates from migmatite zone and granite to upper mylonite zone and lower mylonite zone in the slip system.

本文重点强调：具有从上部主糜棱岩带—混合岩带—花岗岩带—混合岩带—下部主糜棱岩带的岩石垂向分带性的滑动系统是深层次推覆过程中断裂动热变质、超变质作用，以致长英质岩石部分熔融的产物。

Rickets is a ''failure of the bony matrix to mineralize,'' Baker said.

佝偻病是一种"骨基质钙化不足"性疾病，患此病时，骨骼变得软弱，典型佝偻病患儿的腿骨向外弯曲，导致骨骼畸形，严重病例甚至发生抽搐。

Months out from the Games, Mitcham has taken the courageous step of revealing his sexuality to the media for the first time, in an exclusive interview with the Herald.

还剩几个月，米查姆做了一个勇敢的举动，在Herald对他的一次专访中，他第一次向媒体披露了自己的性取向。

The mixed boundary problem was reduced to a system of singular integral equations by means of Fourier transform.

利用Fourier积分变换技术将混合边值问题转化为一对奇异积分方程，通过数值求解奇异积分方程获得含裂纹功能梯度板条分别在剪切和法向载荷作用下的I型和Ⅱ型应力强度因子，并讨论了材料的非均匀性和裂纹相对尺寸对裂纹尖端应力强度因子的影响。

But mathematical science, which is the only real science that the entire civilized world has agreed upon, furnishes unmistakable proof of history repeating itself and shows that the cycle theory, or har monic analysis, is the only thing that we can rely upon to ascertain the future.

但是数学，整个文明世界承认的科学已明白无误地证明了历史的再现性，并向我们展示了循环理论，或类比分析，它是我们发现未来的唯一方法。

The movability of totalP,inorganic P and Olsen-P to deeper layer was descended with soil depths.

土壤中总磷、无机磷和Olsen磷在土壤剖面中向下移动性随着土层的加深而减弱。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。