Delamination dynamics in through-thickness reinforced laminates with application to DCB specimen

Bridged crack models using beam theory formulations have proved to be effective in modeling quasi-static delamination crack growth under large scale bridging conditions in through-thickness reinforced structures. In this paper, beam theory is used to study dynamic mode I crack propagation in through-thickness reinforced laminar structures. In particular, steady state dynamic crack growth for a Double Cantilever Beam (DCB) loaded with a flying wedge is examined. The steady state crack propagation characteristics are mapped out in terms of controllable loading and material parameters including the crack velocity and the properties of the through-thickness reinforcement. For small crack velocities, the through-thickness reinforcement considerably enhances the delamination resistance of the structure. At higher velocities, the kinetic energy term dominates the overall energetics and the relative effect of the reinforcement on the delamination resistance is insignificant. The model suggests a simple fracture test for estimating the properties of the through-thickness reinforcement under dynamic loading conditions.     

Context-Based Network and Application Management on Seamless Networking Platform

A context-based adaptive communication system is introduced for use in heterogeneous networks. Context includes the user's presence, location, available network interfaces, network availability, network priority, communication status, terminal features, and installed applications. An experimental system was developed to clarify the feasibility of using context information to flexibly control networks and applications. The system operates on a seamless networking platform we developed for heterogeneous networks. By using contexts, the system can inform the caller and callee of applications they can access, which are available through the network before communication occurs. Changes in contexts can switch an on-going application to another during actual communication. These functions provide unprecedented styles of communication. A business scenario for a seamless networking provider is also presented. Dr. Morikawa has also been in charge of NICT's Mobile Networking Group. Masugi Inoue received his B.E. from Kyoto University in 1992 and his M.E. and D.E. from the University of Tokyo in 1994 and 1997, all in the field of Electrical Engineering. He is currently a senior researcher at the Yokosuka Radio Communications Research Center under the National Institute of Information and Communications Technology (NICT), Japan, and has been engaged in R&D on ultrahigh-speed WLANs and mobile networking. He joined the Communications Research Laboratory (CRL) of the Ministry of Posts and Telecommunications, Japan, in 1997, which was reorganized as NICT in April 2004. He was a visiting researcher at Polytechnic University in Brooklyn, New York in 2000. Khaled Mahmud received his B.Sc. (Eng.) in Electrical and Electronics Engineering from the Bangladesh University of Engineering and Technology in Dhaka in 1991. He received his M.E. and Ph.D. in the same field from Shizuoka University in Japan, in 1997 and 2000, respectively. He was a research fellow at NICT, Japan, from 2000 to 2004. He is currently an Assistant Professor in the Department of Computer Science and Engineering at North South University, Bangladesh. His research interests include modulation-demodulation techniques, software radio, mobile communication systems, wireless Internet, and IP mobility technologies. Homare Murakami received his B.E. and M.E. in Electronic Engineering from Hokkaido University in 1997 and 1999. In 2004, he received the Young Investigators Award from IEICE. He is currently a researcher at NICT's Mobile Networking Group. He is also an industrial PhD student in Aalborg University since 2003. His interest areas are naming scheme, wireless TCP and new transport protocol, IP mobility, fast handover method, and location management. Mikio Hasegawa received his B. Eng, M. Eng., and Dr. Eng. in 1995, 1997, and 2000 from Science University of Tokyo. From 1997 to 2000, he was a Research Fellow of the Japan Society for the Promotion of Science (JSPS). He is currently a senior researcher in Mobile Networking Group, National Institute of Information and Communications Technology, and a technical advisor in ChaosWare Inc. His research interests include applications of chaotic dynamical theory, combinatorial optimization, mobile networks, and ubiquitous computing. Hiroyuki Morikawa received his B.E., M.E., and D.E. in Electrical Engineering from the University of Tokyo in 1987, 1989, and 1992. He is currently an Associate Professor in the Department of Frontier Informatics at the University of Tokyo and is in charge of NICT's Mobile Networking Group. His research interests are in the areas of computer networks, mobile computing/networks, ubiquitous computing, and network services. He serves as Editor of Transactions of the IEICE and has been on the technical program committees of IEEE/ACM conferences and workshops. He sits on numerous telecommunications advisory committees and frequently serves as a consultant to the government.     

斜轧穿孔机孔型优化系统的研制

开发了主要功能为穿孔工具优化设计、穿孔调整参数优化计算以及毛管横向壁厚均匀性分析的斜轧穿孔机孔型优化系统。该系统不仅可用于斜轧穿孔工具设计和离线分析，还可用于指导穿孔机操作。     

Disconnected Processes, Mechanisms and Architecture for Mobile E-Business

With the tremendous advances in hand-held computing and communication capabilities, rapid proliferation of mobile devices, and decreasing device costs, we are seeing a growth in mobile e-business in various consumer and business markets. In this paper, we present a novel architecture and framework for end-to-end mobile e-business applications (e.g., point of sales). The architecture takes into consideration disconnection, application context, synchronization, transactions and failure recovery modes to provide mobile users with seamless and transparent access to business transactions and business-context specific data. In our architecture, we consider a novel business process design based on state-machines and event management to handle disconnection, resource limitations and failures. We designed, implemented and deployed a system for mobile e-business on clients (e.g., PDAs and PocketPCs) integrated with private exchanges and sell-side servers. The state-machine model with failure recovery mechanisms enables handling of one-to-many and many-to-one disconnections in large mobile e-business environments. The e-business framework on mobile clients is implemented based on J2ME, Webservices, and open XML standards. A detailed performance study of commerce transactions was done on different mobile client devices with diverse computing, memory and storage capabilities. We compare the performance of a purchasing application and the middleware on various devices such as PDAs and Laptops. We demonstrated that for small devices with limited capability the performance is reasonable. For devices with more computing capability, the response time is excellent.     

20#钢钢管的应用探讨

以20^#钢为例，通过对不同标准的对应、比较和分历，阐述正确选择材科的重要性。     

Tiling technology for large‐area direct‐view displays

Abstract— In this paper, the optical and system characteristics of large‐area displays based upon ITrans tiling technology is described. The characteristics of these displays are compared to those of other large area display technologies.     

市场自我定位产品开发创新流程整体优化--试论中国钢管业发展面临的转折点和平衡点

以较详尽的资料和数据，分析了国外焊管和无缝管从20世纪70年代至今的发展情况。在国外，焊管在钢管市场上的占有率已达80％，在很多方面替代了无缝管。对比国内外的发展状况，认为我国钢管业今后的发展趋势也是如此。无缝管的发展应避开焊管的优势，发扬自己不可替代的长处，焊管今后的发展重点应是直缝埋弧焊管，螺旋焊管应着手于技术改造，提高产品档次和质量，扩大市场份额。     

直缝电阻焊钢管与无缝管对比

叙述了直缝电阻焊钢管的生产和应用情况，着重说明直缝电阻焊管与无缝钢管化学成分，力学性能包括冲击韧性、工艺质量和尺寸精度等方面作实物试验研究对比后的情况，并提出了综合评价。     

A review of the effect of stitching on the in-plane mechanical properties of fibre-reinforced polymer composites

This paper reviews over fifty studies into the effect of through-the-thickness stitching on the in-plane mechanical properties of fibre-reinforced polymer composites. Reviewed are the in-plane tensile, compressive, flexure, interlaminar shear, creep, fracture and fatigue properties, although little work has been undertaken on the last three properties. When comparing studies it is apparent that many contradictions exist: some studies reveal that stitching does not affect or may improve slightly the in-plane properties while others find that the properties are degraded. In reviewing these studies it is demonstrated that predicting the influence of stitching on the in-plane properties is difficult because it is governed by a variety of factors, including the type of composite (eg. type of fibre, resin, lay-up configuration), the stitching conditions (eg. type of thread, stitch pattern, stitch density, stitch tension, thread diameter), and the loading condition. The implications of these findings for the use of stitching in lightweight engineering structures are discussed.     

抗磨耐热球墨铸铁热轧无缝钢管顶头的研制

针对热轧无缝钢管均整机顶头的工况条件和失效形式 ,合理设计顶头材质———抗磨耐热球墨铸铁的化学成分 ,并通过试验研究该材质的抗氧化性能 ,热疲劳性能和抗磨热性能 ;试验结果表明 ,抗磨耐热球墨铸铁在 80 0℃氧化增重速度为 2 .410g(m2 ·h) ,不足 45钢的 1/2 ;该材质顶头的抗磨耐热性能优良 ,顶头寿命达到 45钢的 4倍。