数字图像的拷贝翻转移动篡改检测

常见的图像篡改方法之一是将一幅图像中的部分内容复制处理后移动到其他位置产生新的伪造目标.针对将复制区域翻转后再润色粘贴的图像篡改提出了一种基于一组翻转不变的特征向量的检测方法.该检测方法不仅能检测一般的复制-移动-粘贴的行为,而且能检测出欺骗性较强的复制-翻转-移动-粘贴的行为,并能抵抗模糊和加入噪声等用来抹除篡改痕迹的常用润色方法和JPEG有损压缩.对几幅典型篡改图像的检测结果说明了算法的有效性.     

基于Intranet的容灾系统模型的研究与实现

在已有的容灾系统及相关技术基础上,结合大学两校合并后地理位置分散的实际情况,系统分析灾难备份与恢复技术,利用已有的暗光纤组成一个专用的容灾备份网络,合理利用现有资源,设计并实现一种经济、实用的容灾备份系统模型。     

Major histocompatibility complex Class II DRB exon‐2 diversity of the Eurasian lynx (Lynx lynx) in China

The major histocompatibility complex (MHC) is an important component of the vertebrate immune system where it determines which antigens trigger an immune response. In this study the MHC class II DRB genes were investigated in the Eurasian lynx (Lynx lynx) by using a cloning–sequencing method. Analysis in 16 individuals from typical distribution areas in China indicated a relatively high level of allelic diversity: 13 alleles with high sequence polymorphism at 46 variable sites (19.33% of the 238 nucleotides). An overall purifying selection was detected, with one strongly positively selected site located within antigen‐binding sites. The main driving force that led to this allelic diversity pattern is discussed.     

An optimal scheduling algorithm based on task duplication

1.INTRODUCTION Anefficientschedulingofaparallelprogramontothe processorsisvitalforachievingahighperformance fromaparallelcomputersystem.Thetaskduplication basedschedulingisanewapproachtothescheduling problems.Sincethecommunicationtimeamongtasks assignedtothesameprocessorisconsideredtobe negligible,taskduplicationisonewayofreducingthe interprocessorcommunicationoverhead.Usingthis approach,someofthemorecriticaltasksofaparallel programareduplicatedonmorethanoneprocessor.Thiscanpotentiallyred…     

Duplication and Combination of P-Loop Containing Nucleotide Triphosphate Hydrolases Superfamily

In a genome the set of proteins are formed by duplication and combination of domain superfamilies. P-loop containing nucleotide triphosphate （NTP） hydrolases superfamily is massively duplicated and has the most different partner superfamilies among archaea, bacteria and eukarya, Here, we study the distributions of duplication and combination of p-loop containing NTP hydrolases superfamily in 169 completed genomes. When the total number of domains in a genome is larger, duplication and combination partners of p-loop conraining NTP hydrolases are more. This phenomenon is more obvious in metazoa. The distributions of abundance and corn bination of partners relate to the functions of the protein. Those distributions in metazoa are very different from those in other kingdoms because of complexity of metazoa. Finally the relationship between duplication and combination of p-loop containing NTP hydrolases superfamily in different genomes is described. It fits a power law.     

MIS中数据库系统备份机制的研究与实现

本文研究在ＭＩＳ ＤＢＳ双服务器结构下全副本备份的问题。详细讨论了在连续性生产过程中，一台服务器故障时，为保证系统正常运作，服务器的动态切换问题，并给出了切实可行的实现方案。     

一个模体涌现模型（I）全局结构特征

模体涌现是复杂网络局部结构的一种重要特征。基于网络的两种重要生成机制——择优和复制，提出了一个在秩次择优增长和部分复制中嵌入随机子图的混合模型，试图对模体涌现的方式给出一种可能的解释。通过模拟发现该模型不仅能产生网络的局部结构——特定的模体，而且在网络的全局结构特征上也可得出重要的结论：模型产生的网络度指数变化范围在1～3之间，能反映大部分现实网络情况；同时具有负的度相关性，这符合许多非社会网络的实际情况。     

Clustering and Scheduling Method Based on Task Duplication

A new heuristic approach that resembles the evolution of interpersonal relationships in human society is put forward for the problem of scheduling multitasks represented by a directed acyclic graph. The algorithm includes dynamic-group, detachgraph and front-sink components. The priority rules used are new. Relationship number, potentiality, weight and merge degree are defined for cluster＇s priority, and task potentiality for tasks＇ priority. Experiments show the algorithm could get good result in short time. The algorithm produces another optimal solution for the classic MJD benchmark. Its average performance is better than five latter-day representative algorithms, especially six benchmarks of the nines.     

Evolutionary mode of metallothioneins inferred from Cd-MT genes of Tetrahymena

FromTetrahymena thermophila (strain BF5), the coding region ofCd-MT gene was cloned and sequenced, and identified as MTTI isoform. A serial duplicate structure is discovered in its amino acid sequence, which separates the coding region into three parts (Part 1: 7–61: Part 2: 64–118; Part 3: 122–162). The alignments among them and comparison with the corresponding parts of MT1 isoform suggest that MT1 and MTT1 isoforms both come from the same ancient gene that is homologous to Part 1, and Cd-MTs ofTetrahymena are aroused by such ancient gene duplication. The prediction of secondary structures and the analysis of the disulfide-bonding state of cysteine show that there are a lot of differences between MT1 and MTT1 isoforms, which maybe relate to their function mechanism. Foundation item: Supported by KSCX of Chinese Academy of Sciences Grant (SW-102) and the Allocation from the Earmaarked Grant for Hong Kong. Biography: WAN Mingliang (1980-). male, Ph. D. candidate, research direction: molecular ecotoxicology of protozoan.