基于Asp.net的个性化教学系统设计研究

近年来,随着网络教学平台的不断涌现,个性化教学系统的研究和开发成为远程教育中的关键问题和热点。在贝叶斯网络理论支撑下的一种基于Asp.net和Sql-Server数据库技术的个性化教学系统的设计与实现,对系统需求、数据库设计和系统中的技术难点进行了详细的分析和设计。通过系统可以更好的为用户提供个性化学习的帮助,有利于远程教育的发展。     

短路开关电感电阻的测量

短路开关是脉冲放电核聚变研究装置上的重要部件之一。根据需要,我们曾研制了一种性能优良的低电感场畸变型的短路开关。本文着重叙述该开关电感和电阻的测量方法及该开关的触发电路。     

固体有机薄膜开关短时延低抖动触发特性

 实验研究了快脉冲触发固体有机薄膜开关的欠压比、触发脉冲幅值、极性效应和间隙距离对触发特性的影响。固体有机薄膜开关具有较快的脉冲前沿，但其触发性能因条件不同而差异很大。对于自击穿电压为10kV的18μm薄膜，在工作电压9kV，触发脉冲上升沿为1ns,脉冲40ns,幅值9kV条件下，测得开关时延为1.1ns， 时延抖动为0.2ns。     

On the significance of the trigger reaction in the action of the calicheamicin γ1I anti-cancer drug

The significance of the so-called trigger reaction in the reaction mechanism of the calicheamicin γ₁ ^I anti-cancer drug has been studied with ab initio quantum chemical methods. The structures of four fragments of calicheamicin γ₁ ^I , consisting of either 39 or 41 atoms, have been fully optimized using the Becke-Perdew86 density functional method and the 6-31G* basis sets. The four structures constitute members of an isodesmic reaction for which the reaction energy is a direct measure of the change in activation energy of the Bergman reaction, caused by the structural rearrangements of the preceding trigger reaction. This difference in activation energy has been calculated with density functional theory, using the exchange-correlation functional mentioned above, and with second-order M?ller-Plesset perturbation theory (MP2), employing an ANO-type basis set. In both cases a value of 12 kcal/mol is obtained. The study firmly supports the hypothesis that the significance of the trigger reaction is to saturate a double bond in the vicinity of the enediyne group, which counteracts the formation of the biradical state of the drug. The MP2 computations became feasible by a novel implementation of an integral-direct, distributed-data, parallel MP2 algorithm. Received: 10 January 1997 / Accepted: 1 April 1997     

分布式应用程序体系结构到C/S网络数据模型转换机制研究

文章以分布式应用程序体系结构DAPA（Distributed Application Program Architecture)为基础，研究分布计算模型到C／S网络数据模型的转换机制。文章给出总体设计方案，并阐述了相关算法和技术的基本思想，在实现C／S网络数据模型转换的基础上，对B／S网络数据模型转换进行了研究。此项研究直接为MIS软件智能化生产提供服务。     

正反馈过程中Schmitt电路Ve点电位的数值估算

给出Ｓｃｈｍｉｔ电路正反馈过程中的解析公式及相应的曲线，并采用典型电路参数进行了数值估算     

J/ψ→μ+μ- reconstruction in the CMS experiment

In this paper the J/ψ→μ+μ- reconstruction performance in the CMS experiment at the LHC is studied in detail by using B5→ J/ψψ →μμКК events. The reconstruction efficiencies of J/ψ mesons and their decay muons are obtained as a function of the transverse momentum PT and the pseudo-rapidity η. We also study the muon trigger efficiency for this channel with the planned Level-1 trigger and High Level Trigger selection criteria. It was observed that the muon reconstruction efficiency decreases when the two decay muons have a small or large 3D angular separation, which further affects the overall J/ψ reconstruction efficiency.     

基于数据依赖和触发器的简单子任务调度算法

针对在数据库管理系统环境下实现的分布式子任务计算平台,提出了一种基于数据依赖、采用触发器实现的简单分布式子任务调度算法,可有效保证分布式子任务调度的准确性和一定程度的及时性.首先介绍了采用人工划分的基于执行阶段的子任务调度思想,并结合数据依赖调度算法,证明了两者之间的相似性和密切联系,然后进一步提出基于执行阶段的分布式子任务调度算法,为在数据库环境下实现的分布式子任务计算提供了一种简单、快捷、正确的调度算法.     

Coherence resonance and stochastic resonance in directionally coupled rings

In coupled systems, symmetry plays an important role for the collective dynamics. We investigate the dynamical response to noise with and without weak periodic modulation for two classes of ring systems. Each ring system consists of unidirectionally coupled bistable elements but in one class, the number of elements is even while in the other class the number is odd. Consequently, the rings without forcing show at a certain coupling strength, either ordering (similar to anti-ferromagnetic chains) or auto-oscillations. Analysing the bifurcations and fixed points of the two ring classes enables us to explain the dynamical response measured to noise and weak modulation. Moreover, by analysing a simplified model, we demonstrate that the response is universal for systems having a directional component in their stochastic dynamics in phase space around the origin.