基于连续型Hopfield神经网络的系统辨识

连续型Hopfield神经网络(CHNN)可用于优化计算,但其会遭遇较复杂的参数辨识问题.为了较好地解决这一问题,将擅长全局搜索的蚁群-粒子群混合算法用于对系统参数的最优化选取.再将此混合算法与CHNN有机结合,更好地解决参数辨识问题,且能有效避免CHNN在应用过程中陷入局部最优解.最后,将理论结果应用于求解TSP问题来验证其有效性.     

一种改进的数据网格资源调度技术研究

研究了网格资源调度技术。针对网格任务的瞬变性、随机性等特点,提出了一种改进的网格资源调度算法。由于数据网格任务数量庞大,本文采用了并行遗传算法优化网格资源调度。实验结果表明,提出的改进的算法能够对大规模的数据网格任务进行有效调度,是一种有效的方法。     

基于蚁群算法的候选标签子集构造方法研究

为了使构造候选标签SNP子集既包含最多SNP位点,又保证包含的冗余信息尽可能少,本文结合单体型数据及标签SNP选择的特点,依据连锁不平衡度量这一重要遗传现象,以多位点连锁不平衡度量值为优化目标,提出了一种改进的蚁群组合优化算法,提高了搜索组合空间的效率。     

基于遗传算法的BP神经网络在高校图书馆流通服务质量评价中的应用研究

针对高校图书馆流通服务质量问题,建立了评价系统的BP神经网络模型,利用遗传算法对传统的BP神经网络权值进行全局优化运算,提高了网络收敛速度,并经过实例计算验证了该模型的有效性。     

TopRank（k）算法与PageRank算法的比较研究

介绍了一种新的基于接近中心度的排名算法Top Rank（k）,并将其与已有的Page Rank算法进行分析比较,说明了它们各自的特点。通过实证分析,论证了在确定条件下,Top Rank（k）算法比Page Rank算法更有效,突出表现为节省大量时间。     

人造碱基与人工合成生命

文章就人造碱基及相关人工合成生命领域内的代表性研究成果进行了全景式综述,着重介绍了氢键互补及疏水性两种最为主要的人造碱基对,探讨了具有里程碑意义的六核酸分子人工合成生命及其对合成生物学未来发展的影响,简单综述了人造碱基在DNA检测诊断试剂盒等方面的成功应用实例。最后对这一研究领域的前景和面临的挑战进行了展望。     

Application of the Levenshtein Distance Metric for the Construction of Longitudinal Data Files

The analysis of longitudinal data in education is becoming more prevalent given the nature of testing systems constructed for No Child Left Behind Act (NCLB). However, constructing the longitudinal data files remains a significant challenge. Students move into new schools, but in many cases the unique identifiers (ID) that should remain constant for each student change. As a result, different students frequently share the same ID, and merging records for an ID that is erroneously assigned to different students clearly becomes problematic. In small data sets, quality assurance of the merge can proceed through human reviews of the data to ensure all merged records are properly joined. However, in data sets with hundreds of thousands of cases, quality assurance via human review is impossible. While the record linkage literature has many applications in other disciplines, the educational measurement literature lacks details of formal protocols that can be used for quality assurance procedures for longitudinal data files. This article presents an empirical quality assurance procedure that may be used to verify the integrity of the merges performed for longitudinal analysis. We also discuss possible extensions that would permit merges to occur even when unique identifiers are not available.     

基于动量算法的常数模新算法

针对传统常数模算法收敛速度慢的缺点，提出了一种基于动量算法的常数模算法。该算法的权向量更新公式中添加了动量因子，以提高收敛速度。利用水声信道对算法的性能进行仿真研究，仿真结果表明：与常数模算法相比，该算法能较快收敛。     

基于差异性视角的期刊区分性测度及分析研究

当前的期刊评价研究主要集中在影响力、声誉、质量等方面,针对期刊内容差异性的定量研究相对较少。本文从差异性视角来对期刊进行评价分析,提出期刊区分度指标来对期刊内容的差异程度进行度量。以LIS (library and information science)等5个学科的各20种核心期刊为研究对象,首先对LIS期刊的内容差异性进行定量分析与评价,然后从时间维度对LIS学科期刊区分度的变化规律进行了探测,最后从学科维度对不同学科期刊个体和总体区分度的特征进行了分析和探讨。实验结果表明,利用该指标能够很好地度量期刊研究内容差异性,期刊区分度在时间维度上呈现出明显的变化规律,不同学科期刊个体和总体的区分度均具有显著的学科特征。     

Genomic consequences of population decline in critically endangered pangolins and their demographic histories

Pangolins are among the most critically endangered animals due to heavy poaching and worldwide trafficking. However, their demographic histories and the genomic consequences of their recent population declines remain unknown. We generated high-quality de novo reference genomes for critically endangered Malayan (Manis javanica, MJ) and Chinese (M. pentadactyla, MP) pangolins and re-sequencing population genomic data from 74 MJs and 23 MPs. We recovered the population identities of illegally traded pangolins and previously unrecognized genetic populations that should be protected as evolutionarily distinct conservation units. Demographic reconstruction suggested environmental changes have resulted in a population size fluctuation of pangolins. Additionally, recent population size declines due to human activities have resulted in an increase in inbreeding and genetic load. Deleterious mutations were enriched in genes related to cancer/diseases and cholesterol homeostasis, which may have increased their susceptibility to diseases and decreased their survival potential to adapt to environmental changes and high-cholesterol diets. This comprehensive study provides not only high-quality pangolin reference genomes, but also valuable information concerning the driving factors of long-term population size fluctuations and the genomic impact of recent population size declines due to human activities, which is essential for pangolin conservation management and global action planning.