Pressure drop for single and two‐phase flow of non‐newtonian liquids in helical coils

New experimental results on pressure loss for the single and two‐phase gas‐liquid flow with non‐Newtonian liquids in helical coils are reported. For a constant value of the curvature ratio, the value of the helix angle of the coils is varied from 2.56° to 9.37°. For single phase flow, the effect of helix angle on pressure loss is found to be negligible in laminar flow regime but pressure loss increases with the increasing value of helix angle in turbulent flow conditions. On the other hand, for the two‐phase flow, the well‐known Lockhart‐Martinelli method correlates the present results for all values of helix angle (2.56‐9.37°) satisfactorily under turbulent/laminar and turbulent/turbulent conditions over the following ranges of variables as: 0.57 ≤ n′ ≤ 1; Re′ < 4000; Re_l < 4000; Re_g < 8000; 8 ≤ x ≤ 1000 and 0.2 ≤ De′ ≤ 1000.     

基于MIS的计算机应用基础课程教辅软件研发与实践

基于MIS的计算机应用基础课程教辅软件遵循先进务实的设计理念,以满足课程教学一线的实际需求为前提,以提升教学效果、学习效率、拓展教学时空等为目标设计和实现,通过教学实践证明其具有一定的应用价值和推广价值。     

基于Android的校园通应用程序的设计与实现

目前Android手机的普及率在高校里已经相当高,所以研究设计一款基于Android手机的校园服务应用对于广大高校生来说具有深远的现实意义。实现一个基于Android的校园通应用程序,主要功能包括有学院概况、校园通讯、新生专题、校图书馆、成绩课表、课室查询、校园信息、在线问吧、出行指南等模块,基本上满足学生所需要的校园服务,可以在一定程度上提高学生的学习和生活效率。     

基于Windows的通用习题练习系统的设计实现

基于教师教学和学生学习的实际需求,开发基于Windows的通用习题练习系统,具有试题管理、习题练习等功能,可用于教师辅助教学和学生自主学习,通用性和实用性强。系统特点是采用数据文件存储题库,无须联网和配置数据库,易用性强。阐述通用习题练习系统的设计思想、题库数据结构和系统实现,并总结使用效果。     

基于移动设备的操作技能考核系统研究

分析了当前操作技能考核系统的不足,提出了一个基于移动设备的网络操作技能考核系统的设计方案。对系统的整体框架和功能模块进行了介绍,并对各种数据同步方式的优缺点进行了分析比较。最后指出了整个系统存在的不足。     

Towards human motion capture from a camera mounted on a mobile robot

This article describes a multiple feature data fusion applied to a particle filter for marker-less human motion capture (HMC) by using a single camera devoted to an assistant mobile robot. Particle filters have proved to be well suited to this robotic context. Like numerous approaches, the principle relies on the projection of the model's silhouette of the tracked human limbs and appearance features located on the model surface, to validate the particles (associated configurations) which correspond to the best model-to-image fits. Our particle filter based HMC system is improved and extended in two ways. First, our estimation process is based on the so-called AUXILIARY scheme which has been surprisingly seldom exploited for tracking purpose. This scheme is shown to outperform conventional particle filters as it limits drastically the well-known burst in term of particles when considering high dimensional state-space. The second line of investigation concerns data fusion. Data fusion is considered both in the importance and measurement functions with some degree of adaptability depending on the current human posture and the environmental context encountered by the robot. Implementation and experiments on indoor sequences acquired by an assistant mobile robot highlight the relevance and versatility of our HMC system. Extensions are finally discussed.     

Ubi-App: a ubiquitous application for universal access from handheld devices

Universal access from a handheld device (such as a PDA, cell phone) at any time or anywhere is now a reality. Ubicomp Assistant (UA) (Sharmin et al. in Proceedings of the 21st annual ACM symposium on applied computing (ACM SAC 2006), Dijon, France, pp 1013–1017, 2006) is an integral service of MARKS (Sharmin et al. in Proceedings of the third international conference on information technology: new generations (ITNG 2006), Las Vegas, Nevada, USA, pp 306–313, 2006). It is a middleware developed for handheld devices, and has been designed to accommodate different types of users (e.g., education, healthcare, marketing, or business). This customizable service employs the ubiquitous nature of current short range, low-power wireless connectivity and readily available, low-cost lightweight mobile devices. These devices can reach other neighbouring devices using a free short-range ad hoc network. To the best of the authors’ knowledge, the UA service is the only service designed for these devices. This paper presents the details of Ubi-App, a ubiquitous application for universal access from any handheld device, which uses UA as a service. The results of a usability test and performance evaluation of the prototype show that Ubi-App is useful, easy to use, easy to install, and does not degrade the performance of the device.     

多元回归分析及其在辅助决策中的应用

研究了人工神经网络，多元回归分析以及如何应用改进的BP算法求解多元回归模型。给出了在软件产业中进行辅助决策的应用实例，建立了软件销售额与软件产业中博士，硕士和学士数量之间的回归模型，提出了多元回归与一元回归分析相结合的预测方法，并将预测结果与一元回归分析所得的结果进行了对比分析。     

基于作战辅助决策系统的目标威胁评估排序模型

为提高防空武器系统对付多目标的能力,建立了基于辅助决策系统的目标威胁判断排序模型。首先简述了其理论概念,然后介绍了威胁判断排序的辅助决策系统模型,并建立了知识库,分析了空中目标威胁的因素。该模型具有较好的人机交互功能和自学习功能,可自动获取或修改知识库中的知识,能够智能地确定目标的威胁程度,为指挥员进行作战指挥提供了有效的决策工具。     

B超诊断中几种基本测量方法的研究

基于PC平台的辅助测量为B超诊断提供了更高的灵活性和精确度。针对B型基本测量方法,阐述B超诊断中几种基本测量方式的实现,包括距离、角度、曲线周长和面积、椭圆法测周长、面积和体积,具有较强的实际应用价值。其软件实现环境为Windows XP操作系统,Visual C 6.0编程环境。B超诊断对算法的实现效率和精确程度要求较高,算法的优化需进一步考虑。