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921.
移动存储设备安全管理技术的研究与实现 总被引:1,自引:0,他引:1
随着计算机技术的发展,移动存储设备的大量普遍使用,对企业敏感数据带来严重的安全隐患.本文提出一种移动存储设备的安全管理方法,通过提取移动存储设备的特征经加密处理后生成唯一的可信认证信息,当移动设备接入内网时,需通过可信认证才能按权限使用,并给出了方案的实现过程. 相似文献
922.
923.
采用分段设计法研究水处理过程.根据给水浓度和产水浓度要求的不同,以年费用最小为目标,将水处理过程作为超结构模型,进而优化设计段数和每段的工艺参数.研究表明,当进水浓度为5 000 ppm~35 000 ppm时,制备生活用水采用反渗透法处理费用最低,而制备纯水采用反渗透+离子交换联合法处理费用最低;当进水浓度为500 ppm~5 000 ppm时,前者采用电渗析法处理费用最低,而后者采用电渗析+离子交换联合法处理费用最低;当进水浓度小于500 ppm时,制备纯水采用离子交换法费用最低. 相似文献
924.
仿昆扑翼飞行器全解耦控制 总被引:1,自引:0,他引:1
针对仿昆扑翼飞行器飞行控制所面临的欠驱动问题,基于平均理论,提出采用周期时变反馈策略控制仿昆扑翼飞行器的策略,并给出了设计周期时变反馈控制器的输入参数化设计方法.该方法对飞行昆虫的扑翼运动进行仿生模拟,通过调整根翅运动参数,实现了对6个方向气动力和力矩的独立控制.本质上就是用参数表示欠驱动系统的输入,并以此构造周期时变反馈函数;从而在原系统中引入更多数目的独立控制量,将原系统转化为完全能控系统.然后,将此可控系统线性化,并利用线性反馈控制器设计工具设计其反馈控制律.仿真结果表明,基于该策略设计的控制器具有响应速度快、稳定误差小、鲁棒性强等特点. 相似文献
925.
926.
基于TMS320F2812的液晶显示模块接口设计 总被引:3,自引:0,他引:3
为适应工业应用现场以及智能化仪器仪表前端显示的需要,阐述了TMS320F2812DSP和QH2001液晶显示模块的原理及特性,提出了一种基于高速DSP处理器控制低速液晶显示模块的接口设计方案,并对该方案的硬件接口电路和软件驱动程序进行了设计,同时给出了软、硬件实现的相应电路图、程序流程图以及具体程序段;实验调试表明,设计方案结构简单、成本低、抗干扰能力强、显示性能稳定可靠,达到设计要求,能够有效解决高速DSP对低速LCD的驱动及显示问题,并取得了良好的显示效果,对其它便携式系统显示终端的设计也具有一定参考价值。 相似文献
927.
The delay‐dependent stability problem of linear continuous/discrete systems with time‐varying delay is investigated based on a piecewise analysis method (PAM). In the method, the variation interval of the time delay is firstly divided into several subintervals. By checking the variation of the Lyapunov functional in every subinterval, some new delay‐dependent stability criteria are derived. Several numerical examples show that our method can lead to much less conservative results than those in the existing references. Moreover, when the number of the divided subintervals increases, the corresponding criteria can provide an improvement on the results. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
928.
Youn‐Gyoung Chang Seong‐Hee Nam Nam‐Kook Kim Yun‐Ho Kook Jinook Kim Soon‐Sung Yoo Chang‐Dong Kim In‐Byeong Kang In‐Jae Chung 《Journal of the Society for Information Display》2009,17(4):301-307
Abstract— Recently, potential breakthrough technologies for low‐cost processing of TFT‐LCDs and new process developments for flexible‐display fabrication have been widely studied. A roll‐printing process using etch‐resist material as a replacement for photolithographic patterning was investigated. The characterization of the properties of patterns formed in roll printing, a method to fabricate cliché plates for fine patterns, and the design of a new formulation for resist printing ink is reported. The pattern position accuracy, which is one of the most important issues for the successful application of printing processes in display manufacturing was studied and how it can be improved by optimizing the blanket roll structure is explained. New design rules for the layout of the thin‐film‐transistor array was derived to improve the compatibility of roll printing. As a result, a prototype 15‐in.‐XGA TFT‐LCD panel was fabricated by using printing processes to replace all the photolithographic patterning steps conventionally used. 相似文献
929.
Jae Kyeong Jeong Jong Han Jeong Hui Won Yang Tae Kyung Ahn Minkyu Kim Kwang Suk Kim Bon Seog Gu Hyun‐Joong Chung Jin‐Seong Park Yeon‐Gon Mo Hye Dong Kim Ho Kyoon Chung 《Journal of the Society for Information Display》2009,17(2):95-100
Abstract— A full‐color 12.1‐in.WXGA active‐matrix organic‐light‐emitting‐diode (AMOLED) display was, for the first time, demonstrated using indium‐gallium‐zinc oxide (IGZO) thin‐film transistors (TFTs) as an active‐matrix backplane. It was found that the fabricated AMOLED display did not suffer from the well‐known pixel non‐uniformity in luminance, even though the simple structure consisting of two transistors and one capacitor was adopted as the unit pixel circuit, which was attributed to the amorphous nature of IGZO semiconductors. The n‐channel a‐IGZO TFTs exhibited a field‐effect mobility of 17 cm2/V‐sec, threshold voltage of 1.1 V, on/off ratio >109, and subthreshold gate swing of 0.28 V/dec. The AMOLED display with a‐IGZO TFT array is promising for large‐sized applications such as notebook PCs and HDTVs because the a‐IGZO semiconductor can be deposited on large glass substrates (larger than Gen 7) using the conventional sputtering system. 相似文献
930.
User experimentation: an evaluation of velocity control techniques in immersive virtual environments
While many of the existing velocity control techniques are well designed, the techniques are often application-specific, making
it difficult to compare their effectiveness. In this paper, we evaluate five known velocity control techniques using the same
experimental settings. We compare the techniques based on the assumption that a good travel technique should be easy to learn
and easy to use, should cause the user to have few collisions with the VE, should allow the user to complete tasks faster,
and should promote better recollection of the environment afterwards. In our experiments, we ask twenty users to use each
velocity control technique to navigate through virtual corridors while performing information-gathering tasks. In all cases,
the users use pointing to indicate the direction of travel. We then measure the users’ ability to recollect the information they see in the VE,
as well as how much time they spend in the VE and how often they collide with the virtual walls. After each test, we use questionnaires
to evaluate the ease of learning and ease of use of the velocity control technique, and the users’ sense of presence in the
environment. Each of the travel techniques is then evaluated based on the users’ performances in the VE and the results of
their questionnaires. 相似文献