基于CORBA分布式体系结构的合同管理系统

为解决信息不对称问题,通过对CORBA(Common Object Request Broker Architecture)规范技术原理分析,结合合同管理特点,提出了一个基于CORBA分布式结构的合同管理系统的设计方案。简述了分布式合同管理系统的体系结构和系统组成,实践证明该设计方案与传统的合同及项目管理系统相比较,能够满足分布式合同管理的要求。     

Effective capacity analysis of NOMA with transceiver hardware and SIC imperfections

In this paper, we study the performance of the non-orthogonal multiple access (NOMA) networks. By considering two practical factors of residual hardware impairments (RHIs) and imperfect serial interference cancellation (ipSIC), we adopt effective capacity as a metric to characterize the effects of latency on the performance of NOMA networks and derive the analytical expressions of the effective capacity for the near user (NU) and the far user (FU). For further insights, we provide asymptotic analysis by invoking high signal-to-noise ratio (SNR) slope and high SNR power offset. Numerous analytical and simulated results have shown that: (1) The effective capacities of NU and FU are positively proportional to the SNR at low SNR, while at high SNR, the effective capacities approach to the constants; (2) Comparing the two users of the considered NOMA network, the effective capacity of NU shows pronounced advantages under the requirements of low quality of service. (3) RHIs are detrimental to the effective capacities of both NU and FU, especially for the high SNR regime. (4) The effective capacity of NU is limited by ipSIC.     

基于认知电子战的侦察技术

 认知电子战是基于全球电子战领域的一个新兴发展方向。以研究认知电子战的侦察分系统相关技术为重点,分析了目前复杂电磁环境的现状,提出了未来侦察技术的发展需求;以雷达侦察为主总结了传统电子侦察接收机和装备技术的发展现状,结合传统侦察流程提出了能够分选识别已知或未知辐射源目标的认知侦察处理流程,以及具备开放式、一体化、模块化特点的侦察分系统体系和软件架构。     

装备作战试验标准体系研究

 从作战试验指标体系、作战试验条件、作战试验数据采集、作战试验方法、作战试验评定、作战试验程序、作战试验文档等方面分析了装备作战试验标准体系需求,基于体系工程理论,提出了作战试验标准体系的构建思路,规划设计了作战试验标准体系框架,并提出了开展装备作战试验标准化工作的建议。     

The performance of low‐cost commercial cloud computing as an alternative in computational chemistry

The growth of commercial cloud computing (CCC) as a viable means of computational infrastructure is largely unexplored for the purposes of quantum chemistry. In this work, the PSI4 suite of computational chemistry programs is installed on five different types of Amazon World Services CCC platforms. The performance for a set of electronically excited state single‐point energies is compared between these CCC platforms and typical, “in‐house” physical machines. Further considerations are made for the number of cores or virtual CPUs (vCPUs, for the CCC platforms), but no considerations are made for full parallelization of the program (even though parallelization of the BLAS library is implemented), complete high‐performance computing cluster utilization, or steal time. Even with this most pessimistic view of the computations, CCC resources are shown to be more cost effective for significant numbers of typical quantum chemistry computations. Large numbers of large computations are still best utilized by more traditional means, but smaller‐scale research may be more effectively undertaken through CCC services. © 2015 Wiley Periodicals, Inc.     

Quantum supercharger library: Hyper‐parallelism of the Hartree–Fock method

We present here a set of algorithms that completely rewrites the Hartree–Fock (HF) computations common to many legacy electronic structure packages (such as GAMESS‐US, GAMESS‐UK, and NWChem) into a massively parallel compute scheme that takes advantage of hardware accelerators such as Graphical Processing Units (GPUs). The HF compute algorithm is core to a library of routines that we name the Quantum Supercharger Library (QSL). We briefly evaluate the QSL's performance and report that it accelerates a HF 6‐31G Self‐Consistent Field (SCF) computation by up to 20 times for medium sized molecules (such as a buckyball) when compared with mature Central Processing Unit algorithms available in the legacy codes in regular use by researchers. It achieves this acceleration by massive parallelization of the one‐ and two‐electron integrals and optimization of the SCF and Direct Inversion in the Iterative Subspace routines through the use of GPU linear algebra libraries. © 2015 Wiley Periodicals, Inc.     

A Hollow Foldecture with Truncated Trigonal Bipyramid Shape from the Self‐Assembly of an 11‐Helical Foldamer

The creation of self‐assembling microscale architectures that possess new and useful physical properties remains a significant challenge. Herein we report that an 11‐helical foldamer self‐assembles in a controlled manner to form a series of 3D foldectures with unusual three‐fold symmetrical shapes that are distinct from those generated from 12‐helical foldamers. The foldamer packing motif was revealed by powder X‐ray diffraction technique, and provides an important link between the molecular‐level symmetry and the microscale morphologies. The utility of foldectures with hollow interiors as robust and well‐defined supramolecular hosts was demonstrated for inorganic, organic, and even protein guests. This work will pave the way for the design of functional foldectures with greater 3D shape diversity and for the development of biocompatible delivery vehicles and containment vessels.     

Necking in Extrusion Film Casting: Numerical Predictions of the Maxwell Model and Comparison with Experiments

The role of viscoelasticity in determining the extent of necking of a web of molten polymer extruded in an isothermal steady state extrusion film casting (EFC) process is considered. Following a brief review of experimental and theoretical efforts on this problem, analytical and numerical solutions to a well-established model for extrusion film casting using the Maxwell constitutive equation is presented. The extent of film necking was found to either increase or decrease with draw ratio (DR) depending on the Deborah number (De). The locus of points on the draw ratio-Deborah number diagram at which the draw ratio dependence of the necking width inverts was calculated and compared with the locus that separates the unattainable regime from the experimentally accessible regime. Predicted trends were found to be in qualitative agreement with experimental data for various polyethylene grades.     

软硬协同在嵌入式系统教学中的探讨

针对嵌入式系统课程教学中存在的问题,以＂提高学生分析问题、解决问题的能力＂为出发点,探索软硬协同的嵌入式系统教学改革,并提出嵌入式软硬协同教学的设计思路和方法。实践证明,嵌入式软硬协同教学法遵循＂教学做合一＂的教学理念,能有效化解课程中的难点,提高学生的实践能力。     

基于FPGA的立体停车场控制程序设计

以搭载Altera公司FPGA的DE2开发板为平台,使用VHDL硬件语言,建立立方体停车场模型,遵循最优路径设计,研究动态坐标的算法,实现自动控制程序设计,为高校从事数字电路设计的师生及自控领域的工程技术人员,提供一此具有实际应用价值的参考。