共查询到20条相似文献，搜索用时 356 毫秒
1.
This paper presents a serial synchronous scanning mode in fiat panel display （FPD） by adding a latch buffer between the serializer and the driving buffer. Comparing with conventional techniques, the proposed structure can efficiently reduce the brightness loss and improve the transmission performance. Theoretical analysis and experimental results show that the ratio between the lightest weight display time and the relative transmission time is a tradeoff between brightness loss and transmission efficiency. 相似文献
2.
An intelligent detecting system based on wireless transmission is designed. Its hardware includes the card reading module, the wireless digital transmission module, the LCD module, the random password keyboard module and a 16×16 lattice word database based on e-Flash MM36SB020. Its software is a communication protocol between the central control computer and the entrance management base station. To resolve the conflicting problems occurred during the data transmission, a method of delaying time at random is proposed. 相似文献
3.
Illumination system with compound parabolic retro-reflector for single LCOS panel projection display
ZHEN Yan-kun YE Zi ZHANG Wen-zi ZHAO Ting-yu YU Fei-hong 《浙江大学学报(A卷英文版)》2007,8(12):2021-2026
In this paper, a new illumination system with ultra high performance (UHP) lamp is proposed for projection display. Parabolic reflector (PR) and compound parabolic retro-reflector (CPR) were jointly used to collect and collimate the light generated from UHP lamp. A polarization converter system (PCS) was used to increase the light efficiency of the projection display system. A beam transformer between PCS and 2f imaging systems was directly used to make the illumination meet the requirement of projection display system. With the consideration of the loss of reflection, the light efficiency in this projection display system was estimated to be 15.6%. 相似文献
4.
Aharonov-Casher oscillasions of transmission through a mesoscopic ring with a magnetic impurity is investigated. Both spindependent transmission and reflection coefficients of spin-state electrons at zero-temperature are calculated as a function of the textured electric fields and its title angle in the present of spin-flipper scattering. It is found that the spin-exchange interaction can destroy intermittently periodic oscillations of spin-up transmission and reflection coefficients within some small ranges in the adiabatic region of quantum phase. However spin-down transmission and reflection coefficients appear periodic AC oscillations. The calculated results manifest that spindown transmission and reflection coefficients have the same perfect oscillation patterns. In the nonadiabatic region, the behavior of the anomalous AC oscillations are depedent on the difference between the tilt angle of spin and that of texture electric field. 相似文献
5.
We investigated wind-induced vibration control of long-span power transmission towers based on a case study of the Jingdongnan-Nanyang-Jingmen 1 000 kV transmission line project in P. R. China. The height of the cup tower is 181 m with a ground elevation of 47 m, which makes it a super flexible and wind-sensitive structure. Therefore, we should analyze the wind- resistant capacity of the system. We simulated applicable transverse fluctuating wind velocity field, developed a lead-rubber damper （LRD） for controlling wind-induced vibration of long-span transmission towers, deduced LRD calculation model parameter, and researched the best layout scheme and installation method of LRD. To calculate the wind-induced response of tower-line coupling system in seven layout schemes, we used the time history analysis method, and obtained the efficiencies of wind-induced vibration control. LRD deformation research proved that the damp of all LRDs was efficient under the designed wind velocity when they were laid along the edge of tower heads. We studied the controlling efficiency resulting fTom only applying stiffness to the tower polos where the dampers used to be laid under the designed wind velocity. The results show that the controlling efficiency was not ideal when the stiffness is increased on the poles only. Therefore, LRD should conlxibute to both the stiffness and damp of a structure to effectively reduce the dynamic response of a tower-line coupling system under strong winds. We also discussed the controlling efficiency of LRD under static winds. The results show that there was little difference between displacements derived by the finite clement time history method and those obtained by static wind method conducted by a design institute. This means the simulation on space relevant wind velocity field was accurate and reasonable. 相似文献
6.
Agrammatism is a case of a more general linguistic impairment known as Broca’s aphasia.For recent studies just qualitatively analyzed the similarities between time reference and pronominal elements and no experiment have been done.In this paper,the author first introduced the previous studies on time reference and pronominal elements,then designed an experiment to quantitatively test the similarities between them from the aspect of discourse linking. 相似文献
7.
《天津大学学报(英文版)》2010,(2)
The cumulative sum (CUSUM) algorithm is proposed to detect the selfish behavior of a node in a wireless ad hoc network. By tracing the statistics characteristic of the backoff time between successful transmissions, a wireless node can distinguish if there is a selfish behavior in the wireless network. The detection efficiency is validated using a Qualnet simulator. An IEEE 802.11 wireless ad hoc network with 20 senders and 20 receivers spreading out randomly in a given area is evaluated. The well-behaved senders use minimum contention window size of 32 and maximum contention window size of 1 024, and the selfish nodes are assumed not to use the binary exponential strategy for which the contention window sizes are both fixed as 16. The transmission radius of all nodes is 250 m. Two scenarios are investigated: a single-hop network with nodes spreading out in 100 m×100 m, and all the nodes are in the range of each other; and a multi-hop network with nodes spreading out in 1 000 m×1 000 m . The node can monitor the backoff time from all the other nodes and run the detection algorithms over those samples. It is noted that the threshold can significantly affect the detection time and the detection accuracy. For a given threshold of 0.3 s, the false alarm rates and the missed alarm rates are less than 5%. The detection delay is less than 1.0 s. The simulation results show that the algorithm has short detection time and high detection accuracy. 相似文献
8.
The cumulative sum （CUSUM） algorithm is proposed to detect the selfish behavior of a node in a wireless ad hoc network. By tracing the statistics characteristic of the backoff time between successful transmissions, a wireless node can distinguish if there is a selfish behavior in the wireless network. The detection efficiency is validated using a Qualnet simulator. An IEEE 802.11 wireless ad hoc network with 20 senders and 20 receivers spreading out randomly in a given area is evaluated. The well-behaved senders use minimum contention window size of 32 and maximum con- tention window size of I 024, and the selfish nodes are assumed not to use the binary exponential strategy for which the contention window sizes are both fixed as 16. The transmission radius of all nodes is 250 m. Two scenarios are investigated： a single-hop network with nodes spreading out in 100 m~100 m, and all the nodes are in the range of each other; and a multi-hop network with nodes spreading out in 1 000 m~ 1 000 m. The node can monitor the backoff time from all the other nodes and run the detection algorithms over those samples. It is noted that the threshold can significantly affect the detection time and the detection accuracy. For a given threshold of 0.3 s, the false alarm rates and the missed alarm rates are less than 5%. The detection delay is less than 1.0 s. The simulation results show that the algorithm has short detection time and high detection accuracy. 相似文献
9.
The key in the force transmission between the tower and the foundation for offshore wind turbines is to transfer the large moment and horizontal loads.The finite element model of a large-scale prestres... 相似文献
10.
The 3rd generation partnership project (3GPP) has defined the protocols and codecs for implementing media streaming services over packet-switched 3G mobile networks. The specification is based on IETF RFCs on audio/video transport. It also adds new features to achieve better adaptation to the mobile network environment. In this paper, we propose an algorithm for handover detection and fast buffer refill that is based on the existing feedback and signaling mechanisms. The proposed algorithm refills the receiver buffer at a faster pace during a limited time frame after a hard handover is detected in order to achieve higher video quality. 相似文献
11.
选用TI公司的MSP430G2553单片机作为控制核心,实现了LED旋转显示、速度检测、按键切换、光敏调节、电机驱动、红外传输等电路的控制,实现了开机自检、按键切换显示、红外传输、显示亮度自动化调节等功能,完成了在摇动过程中形成的圆形平面内清晰显示出二维字符。 相似文献
12.
该系统采用标准8×8LED点阵模块构成16行×64列点阵显示的LED电子显示屏,用Amtel 89S52单片机控制LED点阵实现动态显示,能完成LED的亮度连续可调、基本汉字显示、滚动显示汉字、信息的左滚屏显示、时间实时显示、数据存储、掉电保护、PC机串口通信、上位机软件和USB接口与计算机通讯等功能。 相似文献
13.
当光纤信道中的光损耗幅度出现较大且快速变化时,在接收端为了能快速地跟踪光信号强度变化、输出稳定信号,文中利用交流耦合接收技术,同时根据光纤传输信道要求,采用8B／10B信道编码技术。使用光损耗快速变化的光纤传输信道对接收组件进行了视频传输实验,在信道光损耗连续变化情况下,视频监视器的输出图像显示正常,无抖动,具有响应速度快和信号输出稳定的特点,满足系统设计要求。 相似文献
14.
以慧的视界去审查教育智慧,可以摆脱将教育智慧视为一种特殊的教育才智的局限,并展示教育智慧所具有的完整结构和真正内涵。教育智慧以教育之慧为本,以教育之智为用,教育之慧对教育之智具有生成、规范和扩展作用。从根本上说,教育智慧是真人与真知的相互融合。 相似文献
15.
采用NPN三极管8050构建的驱动电路和单片机STC89C52实现了高亮度白光LED控制系统.系统分为主控制单元和驱动单元两个部分,采用主从式传输控制方式,驱动单元控制电路实时采集所需的数据,并及时上传至主控制器,而主控制器则根据上传的实时数据,对驱动单元下达设定数据以及控制命令;通过单片机发送PWM脉冲控制高亮度白光LED开关以及自动调光和故障自诊断报警.该系统具有传输距离远、响应速度快、操作简便、性价比高、工作稳定、可靠性高等优点. 相似文献
16.
17.
在无线网络控制系统中,多传感器之间通过信道传输数据时可能会产生时延以及丢包等现象,这种传输误差以指数级增长,造成在某个时刻之后中心处传感器估计值与真实值相差过大。为降低估计误差,通过分析信道参数特征计算出信道临界丢包率,并且给出在信道质量下降时进行切换的判断条件,再利用卡尔曼滤波计算中心处传感器的估计值,在传输出现丢包时进行信道切换。仿真结果表明,通过给出的信道切换方法和切换条件,在同等传输条件下,双信道传输情况下某时刻中心处传感器的估计误差比单信道传输平均下降了23.8%。 相似文献
18.
刘焕茹 《石家庄职业技术学院学报》2011,23(6):22-26
针对大型公共场合需放置多台同步时钟的问题,提出了基于无线数传模块和GPS的时钟信息显示系统设计方案．它利用GPS实现准确授时、无线数传模块实现数据传输、时钟芯片实现时钟信息的存储和更新、8英寸数码管实现时间显示．该时钟信息显示系统的时间同步于GPS授时,走时准确,安装方便． 相似文献
19.
智能大屏幕显示系统既能显示固定内容,又能显示随机内容.固定内容存储在单片机的E2PROM中,供长期显示,随机内容可由PC机编辑,以串行方式发送给单片机,使单片机的功能得以充分发挥,同时也将PC机从显示工作中解放出来,提高了微机的利用率.显示部分采用动态显示技术,既保证了智能大屏幕高亮度、无闪烁等优点,又降低了功耗,提高了系统的性价比. 相似文献
20.
赵伊珍 《新疆职业大学学报》2007,15(4):27-29
进入信息时代,人们越来越重视会计信息的真实性、有用性、时效性等特征,但由于在实际中普遍存在信息不对称。导致会计信息披露不完全、不很透明等现象的普遍存在,不仅影响了投资者对企业的不信任,也在一定程度给投资者造成一定的损失,而信号传递可解决因会计信息不对称等而给投资者造成不利影响等问题,本文就这两个方面来论述信号传递对我国会计信息披露的改进与完善中发挥的作用等。 相似文献