Novel,liquid crystal formula to overcome LTPS LCD image sticking without adjustment of gamma code,optical, VHR and IS evaluation

In this article, novel n-FFS liquid crystal material from Slichem was used in order to elevate the anti-backlight long aging effect; a trace amount of free radical trap HALS-like additive was added, the principle of which can be expressed via Denisov cycle, confirmed by measuring the temporal VHR changes in test cells; three different resolution (FHD ~ QHD) models paired with N19 and N21 were selected for testing by comparing the actual panel. It is verified that the optimized material greatly improves the image sticking performance of the panel and keeping optical performance.     

Design of fault-tolerant large-scale VOD servers: With emphasis onhigh-performance and low-cost

Recent technological advances in digital signal processing, data compression techniques, and high-speed communication networks have made Video-on-Demand (VOD) servers feasible. A challenging task in such systems is servicing multiple clients simultaneously while satisfying real-time requirements of continuous delivery of objects at specified rates. To accomplish these tasks and realize economies of scale associated with servicing a large user population, a VOD server requires a large disk subsystem. Although a single disk is fairly reliable, a large disk farm can have an unacceptably high probability of disk failure. Furthermore, due to real-time constraints, the reliability requirements of VOD systems are even more stringent than those of traditional information systems. Traditional RAID solutions are inadequate due to poor resource usage. Thus, in this paper, we present alternative schemes which provide a high degree of reliability at low disk storage, bandwidth, and memory costs for on-demand multimedia servers. Moreover, we discuss some of the main issues and trade-offs associated with providing fault tolerance in multidisk VOD systems. We would like to impress upon the reader that one of the main points of this paper is the exposition of trade-offs and issues associated with designing fault-tolerant VOD servers. It is not the case that one fault tolerance scheme is absolutely better than another, but rather that one must understand the trade-offs as well as one's system constraints and then choose a fault tolerance scheme accordingly     

Grain boundary effect on electron-beam-induced current in La3Ga5.5Ta0.5O14 crystal

La₃Ga_5.5Ta_0.5O₁₄ crystal recently attracted more attention due to its superior electromechanical properties and high Q × f product. We report that the first electron-beam-induced current experiment on La₃Ga_5.5Ta_0.5O₁₄ single crystal. This method is employed to study the effect of the crystal's grain boundary on the incident electron beam. The experimental results clearly show that when the electron beam scans over the grain boundary of the crystal, a fraction of the carriers recombine at the grain boundary and is unavailable for the current generation. This recombination rate will be enhanced when the electron beam was close to the boundary and cause a dip in the collected current. Although the crystal is an insulator, this effect still can be observed if the coating metal is proper to be chosen. It is also pointed out that the different diffusion lengths of the crystal might be due to the tilted grain boundary.     

Optimal common-mode voltage reduction PWM technique for inverter control with consideration of the dead-time effects-part II: applications to IM drives with diode front end

The main theme of this paper is to demonstrate the applications of the newly developed common-mode voltage reduction pulsewidth-modulation (PWM) technique, which restricts the common-mode voltage to one-third of DC-link voltage, to vector-controlled induction motor drives. As compared to previous common-mode voltage reduction techniques, the presented technique can be applied to the inverter with diode front end and has no adverse effect on the linear modulation range. Therefore, vector-controlled drives using the developed technique for inverter control have a wide speed range. Moreover, the effects of the common-mode voltage reduction PWM technique on speed response for vector-controlled induction motor drives will be fully investigated in this paper. It will be demonstrated by intensive experimental results that speed performance does not deteriorate significantly within the rated speed range.     

Influence of Conductivity of Slag on Decarburization Reaction

By altering the electrochemical properties of slag, the decarburization reaction of Fe3+-based slag withFe-C droplet was studied. The results showed that a lot of free electrons and holes exist in the slag containing transition metal oxides (such as TiO2 and Fe2O3). So electronic conduction in the slag increases. Finally, it led to the increment of the decarburization reaction rate between slag and Fe-C droplet, and mass fraction of carbon remaining indroplet decreases to a lower level.     

Secure centralized spectrum sensing for cognitive radio networks

Spectrum utilization becomes more and more important while new communication techniques keep increasing and the spectrum bands remain finite. Cognitive radio is a revolutionary technology to make use of the spectrum more effectively. In order to avoid the interference to the primary user, spectrum sensing must be sensitive and reliable. Cooperative spectrum sensing (CSS) is one of the ways to increase the reliability of spectrum sensing. The information fusion technique is a key component of CSS. In this paper, we proposed a novel fusion scheme based on spatial correlation technique. We utilize geographical information with reputational weights to propose a two-level fusion scheme called secure centralized spectrum sensing (SCSS). The simulation results show that as the attackers present high density aggregation at some areas, the correct sensing ratio of SCSS is increasing as well even when the number of attackers is very large.     

On Striping Traffic over Multiple IEEE 802.11(b) Wireless Channels

Due to interference, path loss, multipath fading, background noise, and many other factors, wireless communication normally cannot provide a wireless link with both a high data rate and a long transmission range. To address this problem, striping network traffic in parallel over multiple lower-data-rate but longer-transmission-range wireless channels may be used. In this paper, we propose a new striping method and evaluate its performances over multiple IEEE 802.11(b) channels under various conditions. Our extensive simulation results show that this method is quite effective for such an application. S.Y. Wang is an Associate Professor of the Department of Computer Science and Information Engineering at National Chiao Tung University, Taiwan. He received his Master and Ph.D. degree in computer science from Harvard University in 1997 and 1999, respectively. His research interests include wireless networks, Internet technologies, network simulations, and operating systems. He is the author of the NCTUns 2.0 network simulator and emulator, which is being widely used by network and communication researchers. More information about the tool is available at http://NSL.csie.nctu.edu.tw/nctuns.html. C.H. Hwang received his master degree in computer science from NCTU in 2002 and currently is working for a network company. C.L. Chou currently is a third-year Ph.D. student at the Department of Computer Science and Information Engineering, National Chiao TungUniversity (NCTU), Taiwan. He received his master degree in computer science from NCTU in 2002.     

基于媒体用户访问行为偏好模型的代理缓存算法

目前,代理缓存技术广泛应用于改善流媒体传输的服务质量.文章从实际用户日志文件的分析出发,利用发现的用户浏览流媒体对象时的行为分布模型,提出了一种新的视频流媒体缓存算法.仿真结果证明,该算法可以通过记录很少的用户访问信息获取较高的性能表现.     

一种压阻式单片集成MEMS三轴加速度传感器

An integrated MEMS accelerometer has been designed and fabricated.The device,which is based on the piezoresistive effect,accomplishes the detection of three components of acceleration by using piezoresistors to compose three Wheatstone bridges that are sensitive to the only given orientation.The fabrication of the accelerometer is described,and the theory behind its operation developed.Experimental results on sensitivity,crossaxis-coupling degree,and linearity are presented.The sensitivity of X,Y and Z were 5.49 mV/g,5.12 mV/g and 4.82 mV/g,respectively;the nonlinearity of X,Y and Z were 0.01%,0.04% and 0.01%,respectively;the crossaxis-coupling factor of X axis to Y axis and Z axis are 0.119% and 2.26%;the cross-axis-coupling factor of Y axis to X axis and Z axis are 0.157%and 4.12%;the cross-axis-coupling factor of Z axis to X axis and Y axis are 0.511% and 0.938%.The measured performance indexes attain accurate vector-detection in practical applications, and even at a navigation level.In conclusion,the accelerometer is a highly integrated sensor.     

An a-Si:H/a-Si,Ge:H bulk barrier phototransistor with a-SiC:Hbarrier enhancement layer for high-gain IR optical detector

The design and fabrication of a high-gain amorphous silicon/amorphous silicon germanium (a-Si:H/a-Si,Ge:H) bulk barrier phototransistor for infrared light detection applications are reported. The a-Si,Ge:H material featured a lower energy gap and is suitable for the absorption of longer wave light, but it also leads to a low breakdown voltage and high dark current. An additional a-SiC:H thin-film layer was used at the collector/base interface in the conventional amorphous bulk barrier phototransistor to enhance the function of the bulk barrier and obtain high optical gain