高校自动排考系统设计与实现

针对目前高校考务管理的现状,分析了自动排考系统所面临的必要和优化问题.以图论为理论依据,设计了一种能够高效解决这些问题的自动排考算法,并将该算法实现,得到了较好的效果.     

大变幅扬程多机组泵站并联运行水泵性能分析

分析了大变幅扬程下灌溉泵站并联运行水泵机组性能,提出了提高泵站装置效率的方法。     

浅谈保密网中“三员”的工作

分析了保密网中系统管理员、安全保密管理员和安全审计管理员(简称为“三员”)的工作职责,将“三员”的工作分为保密政策法规和标准学习,信息系统日常安全保密管理和协助开展安全保密教育宣传三部分.重点分析了“三员”进行日常保密管理需要做的工作,将信息系统的保密管理对象分为计算机类、服务器类、网络设备、安全保密产品、应用系统、数据库、通信与办公自动化设备等7类,并列举出每类设备的保密管理要点,详细分析了身份鉴别这一点应该如何实现.可为单位信息系统日常保密工作的开展提供技术指导.     

互动教学法对Java EE课程教学效果的影响研究

为了验证互动教学法对教学效果的影响,在《Java EE及其应用》课堂的教学环节中,采用对比的方式,选择一个班级进行传统教学,另一个班级除了传统教学外,还使用Java EE教学互动平台来进行课程教学,在课堂上和课后给学生提供全方位的互动教学。实验结果证明教学互动平台对于教学效果有明显的积极影响,尤其对于70~89分数段的学生来说具有较明显的促进作用,学生卷面成绩有明显提高。     

Highly ion-conductive solid polymer electrolytes based on polyethylene non-woven matrix

Highly ion-conductive solid polymer electrolyte (SPE) based on polyethylene (PE) non-woven matrix is prepared by filling poly(ethylene glycol) (PEG)-based crosslinked electrolyte inside the pores of the non-woven matrix. The PE non-woven matrix not only shows good mechanical strength for SPE to be a free-standing film, but also has very porous structure for high ion conductivity. The ion conductivity of SPE based on PE non-woven matrix can be enhanced by adding sufficient non-volatile plasticizer such as poly(ethylene glycol) dimethyl ether (PEGDME) into ion conduction phase without sacrificing mechanical strength. SPE with 20 wt.% crosslinking agent and 80 wt.% non-volatile plasticizer shows 3.1 × 10⁻⁴ S cm⁻¹ at room temperature (20 °C), to our knowledge, which is the highest level for SPEs. It is also electrochemically stable up to 5.2 V and has high transference number about 0.52 due to the introduction of anion receptor as an additive. The interfacial resistance between Li electrode and SPE is low enough to perform charge/discharge test of unit cell consisting of LiCoO₂/SPE/Li at room temperature. The discharge capacity of the unit cell shows 87% of theoretical value with 86% Coulombic efficiency.     

Performance analysis for range expansion in heterogeneous networks

In this paper, the uplink and downlink performance of a two-tier heterogeneous network （HetNet） with range expansion （RE） is analyzed. Different from previous works, base stations （BSs） are modeled as a spatial Poisson point process. This model can not only capture the irregularity of the BS deployment but also lead to closed form expressions. With the analytical results, the impacts of several key parameters on the coverage and throughput performance are investigated. Our results justifies the effectiveness of RE and Pico deployment. Based on our analyses, certain attention should be made on the RE design to balance the uplink and downlink performance. Our analyses are corroborated by simulations and can thus serve as a flexible and quick guidance for system design without complicated and time-consuming system-level platform construction and simulation.     

浅析数字内容的版权保护与建议

数字技术的迅速发展和广泛应用,互联网、电信移动网络等新兴传输方式和手机、机顶盒、电脑等多媒体终端极大地拓展了数字内容的传输范围。数字内容版权保护的问题日益突出,本文从立法和技术角度阐释了数字内容的版权保护,并提出了数字内容版权保护的建议。     

Effects of silicone oil and polymeric modifiers on the mechanical properties of highly filled LLDPE

The effects of coupling agents, silicone oil, and three types of polymeric modifiers on the mechanical properties of linear low density polyethylene (LLDPE) composites highly filled with aluminium hydroxide [Al(OH)₃] were studied. Polymeric modifiers that contain polar groups, such as silane‐grafted polyethylene (Si‐g‐PE) and acrylic‐acid‐grafted ethylene‐vinyl acetate copolymer (AA‐g‐EVA), improve the mechanical properties dramatically, while nonpolar modifiers improve them to some extent. When Al(OH)₃ was treated using a titanate coupling agent, the silicone oil increased the impact strength and elongation at break of the LLDPE/Al(OH)₃ composites. Introduction of a polymeric modifier containing polar groups destroys the beneficial effects of silicone oil on film mechanical properties, while the introduction of a nonpolar elastomeric polymeric modifier retains the high impact strength and elongation at break. SEM analyses provide the indirect evidence of the encapsulation of silicone oil around the filler. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 121–128, 2002     

基于CFD的汽车空气动力特性分析

汽车的空气动力特性对汽车的动力性、经济性、操稳性以及安全性影响重大.应用计算流体力学(CFD)对汽车的空气动力特性进行计算.建立了不同尾部、不同车身前部的汽车几何模型,并对几何模型进行了流线型处理.设置各模型的计算域初始条件以及选取湍流模型,对计算域内的网格进行剖分,并对网格进行了无关性处理,以消除网格数量对计算结果的影响.对各模型的气动特性进行计算,分别计算了相同车身前部不同车尾外形、相同车尾外形不同车身前部汽车的气动力特性,并将计算结果与经过流线型处理后的汽车进行对比,以分析汽车车前身和车尾的外形设计对其气动特性的影响.     

Study of UAV tracking based on CNN in noisy environment

Multimedia Tools and Applications - Recently, there are lots of tracking methods proposed to improve the performance of visual tracking in videos with challenging situations, such as background...