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101.
TFT-LCD技术的研究进展与发展趋势   总被引:2,自引:0,他引:2  
介绍了近年来世界TFT LCD技术的研究现状,论述了未来TFT LCD技术的发展趋势  相似文献   
102.
Many economists, policy-makers, and corporate managers have long believed that the operational performance of private enterprises is much more efficient than that of public utilities. However, some researches on changes in efficiency before and after privatization contradict this. The purpose of this paper is to analyze changes in technical and cost efficiency in Chunghwa Telecom Company (CHT) before and after partial privatization.The input-orientation Data Envelopment Analysis (DEA) and Cost-DEA were the research tools used in this study, and the findings showed that the technical efficiency, allocation efficiency, and cost efficiency become worse after partial privatization. Additionally, we found that CHT cannot achieve any significant improvement in cost management under its partial privatization environment. CHT is still restricted by government policies and regulations, thus undermining its ability to achieve any significant improvement in its cost management. In order to improve efficiency for CHT, the government needs to eliminate some regulations and relax its control over CHT, thus creating a completely privatized environment.  相似文献   
103.
基于802.11b与安卓手机操控机器鱼的研究   总被引:1,自引:0,他引:1  
本文介绍了一种以“安卓智能手机”和“802.11b技术”为基础的新型机器鱼操控系统。该系统以安卓平台下的智能手机为操作平台,通过对手机端编写socket程序与802.11b模块建立无线通讯连接,经Wi-Fi转串口模块转码后将手机发出的控制指令传送给单片机,单片机在接收到控制指令后通过编程产生PWM波实现对舵机的控制,从而实现对机器鱼的操控。  相似文献   
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Large-scale deployment of IEEE 802.11 wireless LANs (WLANs) with a high density of access points (APs) has become commonplace due mainly to its potential for numerous benefits, such as ubiquitous service coverage, seamless handover, and improved link quality. However, the increased AP density can induce significant channel contention among neighboring cells, thus causing severe performance degradation and throughput imbalance between cells. There have been a plethora of research efforts to improve the WLAN performance, but most of them focused only on single WLAN environments without accounting for inter-cell contention. The de facto QoS-provisioning mechanism for WLANs, i.e., the Enhanced Distributed Channel Access (EDCA), is no exception to this. The EDCA focuses only on inter-flow priority distinction and has not considered the effect of inter-cell contention which significantly restricts its efficiency. This paper presents an enhanced QoS provisioning framework that takes into account inter-cell level differentiation as well as inter-flow level priority, which may be viewed as extension of QoS provisioning from a single-WLAN domain to a multi-WLAN domain. We also propose an architecture for managing multi-AP systems in which a central controller regulates the wireless channel occupancy of APs by adaptively configuring the cell-level QoS parameters. Our extensive simulation results show that the proposed inter-AP cooperative QoS scheme overcomes the limit of legacy 802.11e and provides a high level of fairness in large-scale densely-deployed WLANs.  相似文献   
107.
In this paper, we describe a new method for restoring digitized vintage video with film wear artifacts. Such artifacts result in partially or completely missing information. To maximize use of observed data, we cast the problem as that of recovering mattes of artifacts. More specifically, we extract the distributions of artifact color and its fractional (alpha) contribution to the frame. To account for spatial color discontinuity and pixel occlusion or disocclusion, we introduce the alpha-modulated bilateral filter. The problem is solved as a 3-D spatio-temporal conditional random field (CRF) with artifact color and (discretized) alpha as states. Inference is done through belief propagation. Results verify the effectiveness of our method. Furthermore, we can produce a synthetically generated vintage footage using extracted artifact information from actual vintage video.  相似文献   
108.
We report on the spectral tunability of white light by localized surface plasmon (LSP) effect in a colour converting hybrid device made of CdSe/ZnS quantum dots (QDs) integrated on InGaN/GaN blue light-emitting diodes (LEDs). Silver (Ag) nanoparticles (NPs) are mixed with QDs for generating LSP effect. When the plasmon absorption of Ag NPs is synchronized to the QW emission at 448 nm, the NPs selectively absorb the blue light and subsequently enhance the QD emission. Using this energy transfer scheme, the (xy) chromaticity coordinates of the hybrid white LED was tuned from (0.32, 0.17) to (0.43, 0.26), and thereby generated warm white light emission with correlated colour temperature (CCT) around 1800 K. Moreover, a 47% enhancement in the external quantum efficiency (EQE) was realized.  相似文献   
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A new vertex selection scheme for polygon-based contour coders is presented. In the proposed method, final vertex points are determined by a 'two-step procedure'. In the first step, the initial vertices are simply selected from the contour, thereby constituting a subset of the original contour, using conventional methods such as the iterated refinement method (IRM) or progressive vertex selection (PVS) method. In the second step, a vertex adjustment process is incorporated to generate final vertices that are no longer confined to the contour and are optimal in view of the given distortion measure. For the optimality of the final vertices, a dynamic programming (DP)-based solution for the adjustment of the vertices is proposed. Consequently, the authors offer two main contributions. First, it is shown that DP can be successfully applied to vertex adjustment. Secondly, the use of DP enables global optimality to be achieved in vertex selection without any iterative processes. Experimental results are presented to demonstrate the superiority of the proposed method over traditional methods  相似文献   
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