网络服务器技术研究与实现

应用服务器响应速度直接影响着计算机网络系统的性能。分析网络服务器工作模式,探讨网络服务器的实现技术,并比较了这些技术优缺点和适用范围,给出具体的网络服务器的实现技术和部分代码。     

The effect of blade angle on the flow and pressure distributions in the vicinity of the diffuser blades of a room air conditioner

Many studies on air-conditioning systems are more focused on the individual thermal comfort rather than the thermal efficiency, due to an increase in health concerns. There are several factors influencing the thermal comfort, such as temperature, humidity, convection and air movement, etc. Numerical analyses were performed to investigate the effect of blade angle on the flow characteristics in the vicinity of diffuser blades of a room air conditioner (RAC), with three different blade discharge angles of 45.1°, 58.6° and 116°. We used the commercial code FLUENT to calculate the two-dimensional steady thermal flow fields with different impeller rotational velocities. The angular velocities were located within the range from 900 rpm to 1200 rpm. Turbulence closure was achieved using a standard k-ɛ model. A moving reference frame (MRF) approach was adopted to simulate the flow field generated by the impeller in an RAC. The results were graphically depicted with various geometrical configurations and operating conditions. This paper was presented at the 7th JSME-KSME Thermal and Fluids Engineering Conference, Sapporo, Japan, October 2008. Youn-Jea Kim received his B.S. degree in Mechanical Engineering from Sungkyunkwan University, Korea, in 1982. He then received his M.S. and Ph.D. degrees from the State University of New York at Buffalo in 1987 and 1990, respectively. Dr. Kim is currently a Professor at the School of Mechanical Engineering at Sungkyunkwan University in Korea. Dr. Kim’s research interests include gas dynamics, MEMS, and fluid-machineries, etc.     

Thermal behavior in a 180-deg turned channel with the perforation divider under rotational condition

This study provided a new configuration of the 180-deg turned channel with a perforation divider. The perforations cross the divider let the coolant at the first duct to bypass into the second duct early, preventing from the local high temperature at the downstream zone. Additionally, the perforation-induced disturbing flow should enhance the total heat transfer. This work experimentally investigated the heat transfer behaviors of such system under the rotational condition. The results indicated that the perforation would reduce the raise of the local heat transfer at the turned region. Besides, the rotation would obviously influence the local heat transfer on the leading and trailing surfaces. Furthermore, the effect of rotation on the total heat transfer was insignificant. Finally, the perforation system with the relative perforation diameter d/D_h = 2/4 had the similar total heat-transfer capacity with that without perforation; the total heat-transfer capacity of the perforation system with d/D_h = 1/4 was around 20% higher than the non-perforation one.     

螺旋压力机打击能量的测试与计算

对螺旋压力机速度及打击能量测不准因素作了分析。采用一些新的测连方法和测能手段,确定了被忽视部分打击能量的存在。并对下行程螺杆末速度的确定以及打击能量的计算方法作了探讨。结果表明,经修正后的打击能量计算公式更精确可靠。     

填充聚合物的旋转成型

本文在理论上探讨了聚合物在旋转成型中填充的可能性。根据填料颗粒在熔体中的运动方程,求出其位移速度V(τ)的函数表达式: V(τ)=α(τ)+mα/6πηγ(e~(-(6πηγ/m)τ)-1) 列出斯托克斯力的平衡方程,在给出有关参数后,便得到模型的旋转极限频率(ω_c): ωc=3/2γ(η⊿b/ρ_1⊿τR)~(1/2) 当模型旋转达到此频率时,则填料颗粒就会均匀分布在整个制品体积中。实验证明,上述理论是合理的。     

面向线程级前瞻的线程划分方法浅析

正确合理的线程划分方法是提取线程级并行性的必要前提，线程级前瞻技术是简化线程划分复杂度提高系统性能的重要手段。本文讨论了几种支持线程级前瞻的典型线程划分方法，在此基础上提出了线程级划分需要解决的关键问题，并蛄合一典型自动线程划分算法进行了具体分析，提出了线程划分需要进一步研究的问题。     

网络游戏中通讯模块的设计与实现

在成功的网络游戏中网络通讯部分起着关键重用,从网络游戏的角度来看,通讯技术在其中起的最重要作用就是把游戏端的数据传送到服务器端,并且游戏端能接收服务器发过来的数据以确定游戏的下一步动作。因此网游通讯部分可分为服务器端和游戏端两部分。本文通过分析网络游戏的关键技术,并针对网络游戏中的网络通信给出一个切实可行的方案。     

混凝土外加剂生产线操作平台的设计

LabVIEW具有的其它软件无可伦比的优点使其被广泛的应用在开发测试、测量和控制系统中.本文采用LabVIEW软件来编写混凝土外加剂生产线操作平台.     

利用软件线程集成技术实现硬件到软件的转移

该文介绍了线程集成，一种在通用单片微处理器或微控制器上低耗并行执行的新方法，后级编译技术有效地插入多个控制线程，并提供细粒度的多个线程而不用上下文切换的方法，这样允许用软件完成实时的功能来代替专用外围硬件。该文研究了在主线程中集成实时客户线程时的代码转移，生成的集成线程能满足所有的实时性，线程集成的概念和代码转移被应用到实际中来检验这种方法的可行性。