依托网络教学平台 提高课堂教学效果

网络教学作为一种新的辅助教学手段,是目前教学改革主要研究的方向之一。通过对网络教学平台的功能分析,探讨了在网络教学平台上进行教学资源的建设、交流互动教学活动的开展和虚拟实验室的建设,通过应用实践证明,充分利用网络教学平台的优势,能有效地提高课堂教学质量和效率,培养学生的学习能力、实践能力和创新能力。     

An update-based step-wise optimal cache replacement for wireless data access

Many network applications requires access to most up-to-date information. An update event makes the corresponding cached data item obsolete, and cache hits due to obsolete data items become simply useless to those applications. Frequently accessed but infrequently updated data items should get higher preference while caching, and infrequently accessed but frequently updated items should have lower preference. Such items may not be cached at all or should be evicted from the cache to accommodate items with higher preference. In wireless networks, remote data access is typically more expensive than in wired networks. Hence, an efficient caching scheme considers both data access and update patterns can better reduce data transmissions in wireless networks. In this paper, we propose a step-wise optimal update-based replacement policy, called the Update-based Step-wise Optimal (USO) policy, for wireless data networks to optimize transmission cost by increasing effective hit ratio. Our cache replacement policy is based on the idea of giving preference to frequently accessed but infrequently updated data, and is supported by an analytical model with quantitative analysis. We also present results from our extensive simulations. We demonstrate that (1) the analytical model is validated by the simulation results and (2) the proposed scheme outperforms the Least Frequently Used (LFU) scheme in terms of effective hit ratio and communication cost.     

基于智能客户端的巡检系统设计与实现

针对健康检查中心医生外出进行健康检查作业时,健康检查系统无法离线使用的问题,本文应用智能客户端技术构建巡检系统。该巡检系统可以在离线状态完成健检系统功能,待系统连线以后,通过调用Web Service访问健康检查中心数据库进行数据上传和下载。对系统进行总体设计,给出体系结构图,并且详细介绍相关技术及实现。     

雷达跟踪系统的数据显示

介绍用单片机与制导雷达显示器组成的数据显示系统的设计,并且将目标的高度以数字的形式在显示器上显示,缩短操纵员的训练时间,完成了旧系统的改造升级。     

高校精品课程网络资源建设及有效利用的研究

精品课程的网络化建设与教学资源的共享突破了传统课程学习的时空限制,使精品课程的示范作用得到了真正的体现.基于淮阴工学院校级精品课程<大学计算机信息技术>,对于高校精品课程网络资源的建设及有效利用方面进行探讨.     

微波物位计测量干扰因素的研究

随着高精度微波物位计在储罐系统中的大量使用,其在实际工况中的测量精度得到了越来越多的关注.从频率源、天线形式、微波的测量技术以及信号的检测和处理算法等几个方面介绍了微波物位计的设计要素.说明了影响微波物位计测量的因素主要体现在安装方式和安装位置、信号的强度以及测量介质气相状况等.详细叙述了实际工作中采用较多的微波物位计的测量值修正方法,对广大工程技术人员的选型、安装和调试,乃至新产品研发具有一定的借鉴和参考作用.     

遗传算法与文本特征选择方法相结合的研究

对文本特征选择的传统方法进行了深入分析并对各自的优缺点进行了详细的对比;其次,通过利用遗传算法自身的寻优特点,把它与传统特征选择方法相结合,并得出了算法。最后,在对各自算法进行了分析,表明了在性能上有了明显的提高。     

飞机电气设备自动测试系统设计

从国内外飞机检测技术的现状入手,通过对飞机电气设备自动化检测的需求进行分析,设计了飞机电气设备自动测试系统,介绍其总体结构和工作原理,详细论述了硬件系统的各部分组成与功能,并给出软件系统的设计方案.在实际应用中,实现了飞机电气设备测试的自动识别,具有良好的扩展性,解决了人工测试方式费时费力的问题.     

Reducing control points in lofted B-spline surface interpolation using common knot vector determination

A new algorithm for reducing control points in lofted surface interpolation to rows of data points is presented in this paper. The key step of surface lofting is to obtain a set of compatible B-spline curves interpolating each row. Given a set of points and their parameterization, a necessary and sufficient condition is proposed to determine the existence of interpolating B-spline curves defined on a given knot vector. Based on this condition, we first properly construct a common knot vector that guarantees the existence of interpolating B-spline curves to each row of points. Then we calculate a set of interpolating B-spline curves defined on the common knot vector by energy minimization. Using this method, fewer control points are employed while maintaining a visually pleasing shape of the lofted surface. Several experimental results demonstrate the usability and quality of the proposed method.     

Layered image coding using the DCT pyramid

A block-based subband image coder that exploits the ability to perform decimation in the discrete cosine transform (DCT) domain to effect a pyramidal data structure is described. The proposed "DCT pyramid" has a distinct feature of improved image rendition properties without the associated blocking artifacts at low bit-rates.