基于UAS模式的馆际互借与文献传递系统认证方式初探

本文通过分析高校数字图书馆馆际互借与文献传递系统用户身份认证方式的发展过程,重点阐述基于CALIS馆际互借系统的UAS联合认证方式.共享了本校图书馆使用UAS联合认证方式的一些体会.     

质量管理也要与时俱进--换版认证前先推行新标准必要性刍议

新颁布的ISO9000：2000标准，融资了世界各国质量管理的理论研究成果与实践经验，为企业进一步提高质量管理水平和市场竞争力，提供了新机遇，已获得94版ISO9000标准审核认证证书的企业，尽管证书有效期未到，但也应及时学习贯彻推行新的标准。     

用于无损检测的三坐标定位控制系统

介绍了用于对物体内部进行无损伤检测的控制系统。文中给出了控制系统的总体结构及速度控制算法。该系统采用变M/T测速方法,弥补了M/T测速方法的不足,获得了很好的测速效果。     

基于装配模型的冲模CAD系统变型设计

主要研究了在基于装配的冲压模具开发中，冲模变形设计所涉及到的的主要问题，提出了使用由模具结构骨架和冲压件特征骨架来构造冲压模具CAD系统的装配模型的顶层骨架。通过装配顶层骨架来支持装配设计环境下设计信息的动态传递；正确和灵活的表示各子装配和零件间的基本特征以及相关联性和依赖性；并与参数化设计技术结合传递设计信息到下层的各个子系统。该方法可以充分支持模具结构的变形设计，减少冲模CAD系统模具装配结构的分类，使得系统的开发结构更加清晰并易于实施。     

快速组合设计平台下的变型设计与装配系统

综述了快速组合设计平台的体系结构,以三维CAD软件Solidworks为例阐述了与运行平台的集成、零部件的变型设计和产品模型图的自动装配技术.实践证明,所开发的设计系统可明显地提高企业设计资源的重用,并缩短订单产品的设计时间.     

蓝牙资格认证要点

蓝牙资格认证的核心规范带来了物理层、链路层和同步适配层的新测试要求。介绍了蓝牙资格认证的四个要点,包括蓝牙资格认证流程、蓝牙技术联盟会员须知、蓝牙资格认证版本、蓝牙组网技术认证与测试规范,旨在为有蓝牙认证需求的企业提供帮助。     

A Novel Multiple Dependent State Sampling Plan Based on Time Truncated Life Tests Using Mean Lifetime

The design of a new adaptive version of the multiple dependent state (AMDS) sampling plan is presented based on the time truncated life test under the Weibull distribution. We achieved the proposed sampling plan by applying the concept of the double sampling plan and existing multiple dependent state sampling plans. A warning sign for acceptance number was proposed to increase the probability of current lot acceptance. The optimal plan parameters were determined simultaneously with nonlinear optimization problems under the producer’s risk and consumer’s risk. A simulation study was presented to support the proposed sampling plan. A comparison between the proposed and existing sampling plans, namely multiple dependent state (MDS) sampling plans and a modified multiple dependent state (MMDS) sampling plan, was considered under the average sampling number and operating characteristic curve values. In addition, the use of two real datasets demonstrated the practicality and usefulness of the proposed sampling plan. The results indicated that the proposed plan is more flexible and efficient in terms of the average sample number compared to the existing MDS and MMDS sampling plans.     

一种基于模糊哈希的Android变种恶意软件检测方法

Android移动平台中恶意软件变种数量与日俱增,为了能够高效快速地检测出变种样本,提出一种能够根据Apk中字符串以及函数长度分布特征,来生成模糊哈希值的方法,使得同类变种的恶意软件间的哈希值相似。在对变种恶意软件进行检测时,首先利用k-means方法对已知病毒库所产生的模糊哈希值进行聚类,从而简化病毒库。再利用哈密顿距离来计算其与病毒库中各模糊哈希间哈密顿距离。当距离小于阈值,则表示检测到变种。实验结果表明,提出的方法具有检测速度快,抗干扰能力强等特点。     

Graph-based version control for asynchronous BIM collaboration

Collaboration and communication are two essential aspects of Building Information Modeling (BIM). Current practice and international standards implement BIM collaboration on the basis of domain model federation where loosely coupled models are managed as separated files and coordinated in a mostly manual fashion. The concept has severe limitations regarding concurrency and version control, as the granularity of change tracking remains on the level of complete files and does not reach individual model objects. Due to this lack of change traceability, high manual effort for the subsequent coordination across the domains is generated. These limitations can be overcome by implementing modern approaches of digital collaboration based on object-level synchronization, widely denoted as BIM level 3. This paper presents a sound methodological basis for object-based version control by (1) representing the object networks of BIM models as formal property graph structures and (2) describing changes of the model by graph transformations. Consequently, modifications can be transmitted as graph transformation rules which are subsequently integrated on the receiving side, thus achieving object-level synchronization. The paper provides the underlying theory of describing model changes by means of graph transformations and demonstrates its benefits using the example of domain models implementing the Industry Foundation Classes (IFC) as their underlying data model.     

四种肿瘤体细胞单核苷酸突变检测方法的比较

随着高通量测序成本的不断降低,基于DNA测序技术的肿瘤基因组研究已经成为揭示肿瘤分子机制的主流方法,并在临床诊断和治疗中逐渐得到应用。肿瘤体细胞单核苷酸突变变异 (single nucleotide variant, SNV) 作为最简单的一种基因变异类型,其检测会受到家系多态性、肿瘤异质性、测序和分析误差等多个因素的影响,从而导致一些假阳性的结果。目前,已有一些基于肿瘤基因组测序数据的体细胞 SNV 检测软件,如 Varscan2,Mutect2,Strelka,SomaticSniper 等。本文选取四种典型的检测方法,对每种方法的检测原理进行研究,并使用 ICGC-TCGA 提供的全基因组数据,对上述四种变异检测软件进行测试。参照每种方法的分析流程,获得每种方法识别的候选变异位点集,并与真实的变异位点集合进行比较,分析每种算法的优缺点,从而为研究人员使用这些方法提供指导。