Comparing the mechanical response of di‐, tri‐, and tetra‐functional resin epoxies with reactive molecular dynamics

The influence of monomer functionality on the mechanical properties of epoxies is studied using molecular dynamics (MD) with the Reax Force Field (ReaxFF). From deformation simulations, the Young's modulus, yield point, and Poisson's ratio are calculated and analyzed. Comparison between the network structures of distinct epoxies is further advanced by the monomeric degree index (MDI). Experimental validation demonstrates the MD results correctly predict the relationship in Young's moduli. Therefore, ReaxFF is confirmed to be a useful tool for studying the mechanical behavior of epoxies. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 255–264     

Multiaxial mechanical behavior of aramid fibers and identification of skin/core structure from single fiber transverse compression testing

The transverse and longitudinal mechanical properties of aramid fibers like Kevlar? 29 (K29) fibers are strongly linked to their highly oriented structure. Mechanical characterization at the single fiber scale is challenging especially when the diameter is as small as 15 µm. Longitudinal tensile tests on single K29 fibers and single fiber transverse compression test (SFTCT) have been developed. Our approach consists of coupling morphological observations and mechanical experiments with SFTCT analysis by comparing analytical solutions and finite element modeling. New insights on the analysis of the transverse direction response are highlighted. Systematic loading/unloading compression tests enable to experimentally determine a transverse elastic limit. Taking account of the strong anisotropy of the fiber, the transverse mechanical response sheds light on a skin/core architecture. More importantly, results suggest that the skin of the fiber, typically representing a shell of one micrometer in thickness, has a transverse apparent modulus of 0.2 GPa. That is around more than fifteen times lower than the transverse modulus of 3.0 GPa in the core. By comparison, the measured longitudinal modulus is about 84 GPa. The stress distribution in the fiber is explored and the critical areas for damage initiation are discussed. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 374–384     

现代检测技术在数控机床中的应用

介绍现代检测技术及检测装置在数控机床中的应用,详细分析位置检测装置在数控机床中的重要作用,归纳总结检测元件发生故障的原因,以达到经验共享的目的。     

Die Organisation und die Entwicklung der Direktion N„Isotop“

Bis zur Bildung der Direktion ?Isotop“ wurden in der Volksrepublik Bulgarien Radioisotopengeräte durch verschiedene Institute und Laboratorien entwickelt. In jener Etappc trugen die einschlägigen Forschungs- und Entwicklungsarbeiten der Laboratorien und Institute einen unsystematischen Charakter; sie waren nicht koordiniert und entsprachen nur teilweise den Erfordernissen der Volkswirtschaft. Deshalb ergab sich die Notwendigkeit, eine zentrale Organisation zu schaffen, die die Arbeiten auf dem Gebiet der Anwendung radioaktiver Nuklide zusammenfaßt und leitet.     

Important unanswered questions—1970

This paper was given as the opening address at the 1970 Albany International Conference on Radiation Effects in Semiconductors, and it attempts to establish a general overview of the field by concentrating on recent research developments and important unanswered questions. The continuing importance of impurity-defect interactions, of microscopic defect identification, and of the necessity for more theoretical calculations are emphasized. The rapid development of the field of ion implantation and its close relationship with radiation effects studies are pointed out. It is predicted that research in compound semiconductors will increase rapidly with close beneficial interaction with ion implantation studies.     

广播电视监测信息管理平台的建设

在今天，广播电视应用越来越广泛，由此其监测也显得尤为重要，广播电视监测信息管理平台的建设，作为一个综合的、开放的信息共享、服务平台，可以便捷有效地对广播电视运行的各个环节包括播出、传播、用户等进行监测，以保证广播电视顺利、安全的播出。本文分析了广播电视监测网的主要作用，并就其建设整体架构、技术要求进行了较为全面的探究，以期完善监测系统。     

What installed mobile applications tell about their owners and how they affect users’ download behavior

The rapid growth in the mobile application market presents a significant challenge to find interesting and relevant applications for users. An experimental study was conducted through the use of a specifically designed mobile application, on users’ mobile phones. The goals were; first, to learn about the users’ personality and the applications they downloaded to their mobile phones, second to recommend applications to users via notifications through the use of experimental mobile application and learn about user behavior in mobile environment. The question of how the personality features of users affect their compliance to recommendations is explored in this study. It is found that conscientiousness is positively related with accepting recommended applications and being agreeable is related with the preference for the applications of editor’s choice. Furthermore, in this study, applications owned by the user and the composition of applications under categories and their relation with personality features are explored. It is shown that the number of user owned applications and their category differ according to gender and personality. Having similar applications and the number of applications owned under specific categories increase the probability of accepting recommended applications.     

基于AMF-RPC框架的.NET for flash网络应用程序

Flash动态网站已成为"数据驱动的富媒体应用程序"开发的核心,基于AMF-RPC框架的Flash Remoting技术,能够实现完美的.NET for flash网络应用程序。本文主要介绍AMF-RPC技术,以及在这种技术框架下实现asp.net与flash完美结合。     

计算机体系结构设计原理的易经模型

易经是中华民族宝贵文化遗产，它包含上古时期人们对自然宇宙和人生社会的思想认识、哲学理念和辩证法，代表了先民哲学地把握宇宙的思维成果.现代科学的许多重大发现和突破，如二进制、原子结构、生物遗传DNA等学科理论，都可以从八卦和六十四卦模型中发现与之对应的形态和哲学思维.计算机体系结构设计原理（PPCAD）应是易经这种形态和思维的一种自然现象和映射对象，利用八卦和六十四卦哲学思维和策略，提供PPCAD的思路和策略是本文的目标.本文依据PPCAD中的基本推演理念，提炼出4对基本对立统一推演关系，根据4对基本关系构造了新的易经八卦及六十四卦.同时，结合体系结构设计中的层次模型方法，指出了易经层次模型的特点及动态性.为了便于对PPCAD易经模型的理解，我们选择了10个新卦的例子加以说明和表达，同时也给出了一些PPCAD原则和策略的新观察.我们想指出，我们的新易经模型方法不但可用于计算机体系结构的设计，也可尝试用于其他复杂系统的设计原理.最后，对全文进行了总结，并对下一步的研究进行了展望.