取证

In order to overcome the shortages, a distributed and autonomous computer forensics system was presented.

针对目前取证系统的时效性不足和通信瓶颈等问题，提出了一种分布式自治型计算机取证系统。

This way of autonomous forensics could optimize system performance.

由于取证节点具有自治取证能力，系统的整体性能得到了优化。

Firstly, DWT is applied to the image, and moment invariants is extracted on fixed-size blocks of low-frequency component in wavelet sub-band to yield a reduced dimension representation.

然而，许多实际情况是要求在不依赖任何预签名提取或预嵌入信息的前提下，对图像的真伪和来源进行鉴别，这就是图像盲取证技术，也叫被动取证技术，它是一种新的图像鉴别分析思路。

Based on the summarization of the present research, the future system frame of the blind digital image forensics is proposed. According to the natural characteristics of digital image, the principles of constructing the standard testing database of sample images are also put forward. Moreover, the extensible topology structure is set up and the size of the database needed theoretically is calculated statistically.

在总结前人工作的基础上，提出了数字图像盲取证的系统框架；利用数字图像自然属性特征，根据数字图像取证的测试需求，提出了取证测试专用的标准图像样本数据库建库准则，建立了可拓展的图像库拓扑结构，并利用统计学方法计算了所需的建库规模。

The requirements for this are as follows: no need to analyze the primitive data;the information net system and subsidiary facilities for analyzing must be safe and reliable;signature needed after the data before analyzing;the concrete and detailed account of obtaining process should not only be given,but be classified and stored.

电子取证的要求是：不要对原始数据进行直接分析；分析数据的信息网络系统及其辅助的设备必须安全、可靠；分析前对数据进行数字签名；对数据获取过程进行详细、具体的描述，并归档、保存。电子取证的方法包括：数字鉴定法；数据检查法；数据对比法；数据保护法；数据分析法；证据抽取法。

As to the procedure of obtaining evidence, the writer points out some procedures which are illegal and will result in the invalid of E-mail; as to the authenticity, several methods to identify were concluded and their advantages and disadvantages are also listed. In addition, the writer points out that the laws in force on the authenticity of E-mail were very macroscopic and vague. And there are not concrete laws in effect to identify the authenticity of E-mail without electronic signature and encryption. So the writer explains his views that each links of E-mail's lifecycle should be deeply analyzed and checked to exclude the possibilities of unauthenticity of E-mail.

就取证程序方面，该部分则指出了哪些取证程序是违反法律并可能会导致电子邮件无效；就电子邮件真实性的问题，本文主要从现有立法归纳出几种认定电子邮件真实性的具体方式，并阐述了这些方式的利弊，同时笔者还在该部分指出，现行法律对于电子邮件真实性问题的认识，仍仅停留在宏观层面，显得过于宽泛，尤其是针对未经签署电子签名和加密的电子邮件真实性的认定问题，现行法律没有进行具体规范。

With regard to computer forensics, a data, about 60 pages, focuses on evidence of physical memory.

详细说明：关于计算机取证的，一个资料，大约60页，主要介绍物理内存取证。

In this paper, the stages of computer forensics are presented, and the theories and the realization of the forensics software are described.

介绍了计算机取证的过程以及取证软件的原理和实现，并且给出完整的取证实例。

Since the technological methods and tools of computer forensics are important, a typical case study is presented and analyzed.

阐明了计算机取证的相关法律问题，重点研究了计算机取证的技术方法和工具，并给出了一个计算机取证实验的技术过程。

Research the techniques of the computer forensics for computer operating system and computer networks.

针对具体的数字化侦查取证，以Windows系统为例，对操作系统的数字化侦查取证技术进行了研究；并结合网络中常见的犯罪行为，分析研究计算机网络的数字化侦查取证技术手段。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。