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811.
ROI-based Watermarking Scheme for JPEG 2000 总被引:1,自引:0,他引:1
Yu-Cheng Fan Arvin Chiang Jan-Hung Shen 《Circuits, Systems, and Signal Processing》2008,27(5):763-774
A new region of interest (ROI)-based watermarking method for JPEG 2000 is presented. The watermark is embedded into the host
image based on the characteristics of the ROI to protect rights to the images. This scheme integrates the watermarking process
with JPEG 2000 compression procedures. Experimental results have demonstrated that the proposed watermark technique successfully
survives JPEG 2000 compression, progressive transmission, and principal attacks. 相似文献
812.
In this study, a single unit of planar micro-solid-oxide fuel cell (μSOFC) is investigated numerically to evaluate the influences of flow channel design, oxygen composition, and thermal operating conditions on cell performance. Four flow channel designs are examined under the co-flow configuration: serpentine, double serpentine, rod bundle, and oblique rib. For all designs, the contacts areas of interconnect to electrodes are kept consistent to maintain the ohmic losses at the same level. To characterize the mass transport effects, there are three different compositions, 100% O2, 50% O2/50% N2 and air, fed to the cathode inlet. Different thermal conditions, adiabatic and isothermal, are applied to the outer boundary of the μSOFC and the results are compared. The outcomes suggest that both thermal conditions and oxidant composition show remarkable influences on μSOFC performance. Under adiabatic conditions, the rise of cell temperature causes a decrease in reversible voltage, deteriorating the overall cell competence. When oxygen is diluted with nitrogen, local gas diffusion becomes dominant to the cathode reaction. Bulk flow, on the other hand, plays a minor role in cell performance since there is little deviation in the polarization curves for all flow channel designs, even at high current densities. For comparison, the flow visualization technique is employed to observe the transport phenomena in various flow channel designs. The flow patterns are found to resemble the concentration distribution, providing a useful tool to design μSOFCs. 相似文献
813.
Sun-Yuan Hsieh 《The Journal of supercomputing》2007,39(1):39-57
A graph is distance-hereditary if the distance stays the same between any of two vertices in every connected induced subgraph containing both. Two well-known
classes of graphs, trees and cographs, both belong to distance-hereditary graphs. In this paper, we first show that the perfect
domination problem can be solved in sequential linear-time on distance-hereditary graphs. By sketching some regular property
of the problem, we also show that it can be easily parallelized on distance-hereditary graphs. 相似文献
814.
过程控制级模拟轧钢系统的研制及在热轧试车中的应用 总被引:1,自引:1,他引:0
宝钢集团上海第一钢铁有限公司(后面简称一钢)新建的不锈钢工程1780热轧项目中,为了能在较短周期内完成所有的应用软件开发与测试任务,特别研制了模拟轧钢功能。本论文主要阐述利用计算机的集成思想,结合热轧工艺,来开发模拟轧钢功能,以及利用模拟轧钢进行现场各种情况的模拟测试。 相似文献
815.
为了适应MMS(多媒体短信息业务)的发展,提出了一个基于图像扭曲的变形动画生成机制。该机制不仅能够实时地产生效果新奇、富于戏剧性的GIF动画,而且能够根据不同终端的特点实现图像的自适应处理,从而使在无线网络上传输丰富多彩的图像文件变得更为方便。 相似文献
816.
以无线通讯方式实现多台PLC之间以及PLC与微机之间的数据交换,在遥控监控站上完成对移动设备的控制与监视。 相似文献
817.
This paper is concerned with the achievable performance of adaptive control algorithms. We show that when the only uncertainty is in the form of fixed parameter errors, then there exists an adaptive feedback law whose performance can be made arbitrarily close to that achievable when the system is a priori known. The result is not intended as a practical strategy. Instead, we use it to make the, perhaps obvious, point that meaningful results on performance of adaptive control algorithms must account for non-ideal factors including, at a minimum, noise, parameter time variations and unstructured uncertainty. 相似文献
818.
论文主要介绍了电机的调速方法、变频器的工作原理以及日本FRNIC500G7型变频器在桥式抓斗吊车上的应用,并分析了使用绕线式电机调速与鼠笼式电机变频调速之间的优缺点。 相似文献
819.
Intelligent multisensor surveillance systems consist of several types of sensors, which are installed on fixed and mobile devices. These components provide a huge quantity of information that has to be contrasted, correlated and integrated in order to recognize and react on special situations. These systems work in highly dynamic environments, with severe security and robustness requirements. All these characteristics imply the need for distributed solutions. In these solutions, scattered components can decide and act with some degree of autonomy (for instance, if they become isolated), or cooperate and coordinate for a complete tracking of special situations. In order to cope with these requirements and to better structure the solution, we have decided to design surveillance system control as a multiagent system. This is done by applying an agent-orientated methodology, which is assessed with concrete scenarios. 相似文献
820.
Time-of-flight transient photoconductivity measurements reveal a monotonic increase with the deposition pressure in the hole mobility in polymorphous silicon for samples deposited under hydrogen dilution. With helium dilution, a maximum mobility that matches the highest value from H-dilution samples is measured at the intermediate pressure of 1.4 Torr. The deposition rate of those samples is twice the rate for the H-dilution ones. For the samples with the best hole mobilities, the valence-band tail is comparable to the one of standard hydrogenated amorphous silicon. 相似文献