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41.
Jung Nam Bae Jin Young Kim Geon Kim Yong Tae Lee Jae Sang Cha 《Multimedia Tools and Applications》2012,57(2):359-372
Recently, watermarking based data transmission techniques using terrestrial digital TV signal have been proposed since they
are also cost-free and can overcome the limitations of GPS. However, in the previous watermarking based methods, the detection
accuracy is low and additional data rate is too low. Thus, we propose the throughput enhancement method by employing the TZCD-MBOK
watermarking technique in T-DMB system. By applying the proposed scheme to T-DMB, it allows additional data transmission for
disaster broadcasting and improves efficiency of data transmission in shadow region and indoor to mobile environment through
watermarking spread code. From the simulation results, we confirm the proposed watermarking scheme affected on the existing
T-DMB signal. Moreover, it was also confirmed that the system capacity increases as the power of additional watermarking signal
rose. The results of the paper can be applied to wireless multimedia digital broadcasting systems. 相似文献
42.
René Schneider 《Computing and Visualization in Science》2012,15(5):247-270
Adaptive anisotropic refinement of finite element meshes allows one to reduce the computational effort required to achieve a specified accuracy of the solution of a PDE problem. We present a new approach to adaptive refinement and demonstrate that this allows one to construct algorithms which generate very flexible and efficient anisotropically refined meshes, even improving the convergence order compared to adaptive isotropic refinement if the problem permits. 相似文献
43.
本文设计了一种基于AT89C2051芯片为CPU的家用报警系统,以烟雾探测器、门磁报警器、燃气体探测器等传感器为节点,当收集到异常信息后,由无线网络节点送至报警主机,通过主机报告给预留电话,从而完成了家庭报警系统的硬件组成、软件设计、数据采集与通信策略以及主程序设计,实现对家庭的非法入侵、火灾、燃气泄漏等事故的报警保护。 相似文献
44.
45.
《无机及分析化学》在多媒体教学的应用及思考 总被引:1,自引:0,他引:1
对多媒体技术在无机及分析化学教学的应用进行了,阐述和分析,指出使用多媒体教学应注意的问题。 相似文献
46.
47.
The modern society is fuelled by very comprehensive grids of gas and liquid pipelines. In recent years, various in-pipe robots have been developed for inspection and maintenance tasks inside such pipes. In this paper, a novel in-pipe robot is proposed and developed for gas/oil well interventions at thousands of meters downhole. Due to the nature of such intervention, in-pipe robot design must be capable of carrying a very large payload, as large as 2500?N inside a pipe with diameter as small as 54?mm. The proposed design concept is based on a compound planetary gearing system. One of the major novelties of this design is the use of pipe wall as a ring gear for one stage of the compound planetary gear system; the other novelty is the generation of helical angle when the planetary gears are expanded to press on the pipe wall. The proposed concept is compact, efficient, and has never been reported before. In this paper, the helical angle, the velocity, and load capability of the proposed system will be analyzed. The load transportation capability of the proposed robot is also measured based on an experiment. Initial data have shown great potential in carrying large payloads. 相似文献
48.
Carl Yuheng Ren Victor Prisacariu Ian Reid 《International Journal of Computer Vision》2014,106(3):269-281
We propose a novel regression based framework that uses online learned shape information to reconstruct occluded object contours. Our key insight is to regress the global, coarse, properties of shape from its local properties, i.e. its details. We do this by representing shapes using their 2D discrete cosine transforms and by regressing low frequency from high frequency harmonics. We learn this regression model using Locally Weighted Projection Regression which expedites online, incremental learning. After sufficient observation of a set of unoccluded shapes, the learned model can detect occlusion and recover the full shapes from the occluded ones. We demonstrate the ideas using a level-set based tracking system that provides shape and pose, however, the framework could be embedded in any segmentation-based tracking system. Our experiments demonstrate the efficacy of the method on a variety of objects using both real data and artificial data. 相似文献
49.
50.
沉淀铁催化剂上F-T合成反应的研究 总被引:2,自引:1,他引:2
制备了物相组成为 Quartz- Si O2 ,Hermatite- Fe2 O3 和 Fe2 O3 - Iron Oxide的沉淀铁催化剂 ,研究了该催化剂作用上固定床积分反应器中费托合成反应特性 .发现 2 .6MPa,80 0 h-1,H2 /CO=2 /3,2 60℃~ 2 90℃时 ,随着温度的升高 ,CO和 H2 的转化率增大 ,CO2 选择性减小 ;40 0 h-1,65 0 h-1,80 0 h-1低空速和 2 4 0 0 h-1,32 0 0 h-1,40 0 0 h-1,640 0 h-1高空速时 ,随着空速的升高 ,H2转化率、CO转化率选择性下降 ,CO2 的选择性升高 ;2 80℃ ,2 .6MPa,H2 /CO进料比 2 /3,1 /1 ,2 /1时 ,随着 H2 /CO进料比的增加 ,CO转化率 ,H2 /CO利用比和 CH4选择性都增加 ,H2 转化率和 CO2选择性减小 . 相似文献