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101.
Novel error concealment method with adaptive prediction to the abrupt and gradual scene changes 总被引:1,自引:0,他引:1
Soo-Chang Pei Yu-Zuong Chou 《Multimedia, IEEE Transactions on》2004,6(1):158-173
In this paper, the impact of scene change on the conventional error concealment method is addressed and a novel error concealment method is proposed to improve the insufficiency of the conventional temporal error concealment algorithm due to the occurrence of scene change. Combining with the low complexity scene change detection algorithm using macroblock type information, the corrupt blocks resulting from bit errors are concealed either temporally or spatially depending on whether or not an abrupt scene change is found. In the case of gradual scene change, a novel error concealment method of interpolation and extrapolation is proposed to utilize the linear property of gradual scene change sequence, and effectively reduce the concealment error in comparison with the conventional algorithm. A great improvement of about 3 to 5 dB PSNR on average and 6 to 8 dB in some cases is obtained with very little memory and computation overhead. 相似文献
102.
H. C. Lam W. W. Ki A. L. S. Chung P. Y. Ko A. C. Y. Lai S. M. S. Lai P. W. Y. Chou & E. C. C. Lau 《Journal of Computer Assisted Learning》2004,20(2):114-123
Effective teaching should focus the attention of learners to its essential aspects. It follows that instructional software can be designed in such a way that allows learners to experience the important variations in the critical aspects of the content to be learned. This paper reports on the experience of designing such special kinds of instructional learning objects for the learning of Chinese characters. The design of these learning objects takes into consideration not only what Chinese characters are all about but also how learners commonly make errors while they learn to write the characters. Out of the analysis of these learners' errors, variations in the structural features of Chinese characters were pulled out and embodied in the design of the learning objects. Learners tinkering with the learning objects can thus implicitly develop a sense of the structural features or regularity of Chinese characters, which most importantly should prepare the learners to learn more new characters in the future. The main proposal of this paper is the notion of this variation‐affording instructional software that allows learners to attend to the essential aspects of what is to be learned. Furthermore, the idea of the learning object also differs from other instructional software in its small, self‐contained and reusable nature, such that teachers can flexibly embed the learning objects into their own teaching materials. 相似文献
103.
Yen-Shin Lai Po-Sheng Chen Hsiang-Kuo Lee Chou J. 《Industry Applications, IEEE Transactions on》2004,40(6):1613-1620
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. 相似文献
104.
A. Norman A. Ahmed J. Chou A. Dalal K. Fortson M. Jindal C. Kurz H. Lee K. Payne R. Rando K. Sheppard E. Sublett J. Sussman I. White 《Computational Economics》2004,23(2):173-192
A consumer entering a new bookstore can face more than 250,000alternatives. The efficiency of compensatory and noncompensatory decisionrulesfor finding a preferred item depends on the efficiency of their associatedinformation operators. At best, item-by-item information operators lead tolinear computational complexity; set information operators, on the other hand,can lead to constant complexity. We perform an experiment demonstrating thatsubjects are approximately rational in selecting between sublinear and linearrules. Many markets are organized by attributes that enable consumers toemploya set-selection-by-aspect rule using set information operations. In cyberspacedecision rules are encoded as decision aids. 相似文献
105.
Fuh-Der Chou 《The International Journal of Advanced Manufacturing Technology》2007,35(5-6):587-595
This research is motivated by the scheduling problem found in the burn-in operation of semiconductor final testing, where
jobs are associated with release times, processing times, and sizes. The burn-in ovens are modeled as batch-processing machines
which can process a batch of several jobs as long as the total sizes of the jobs do not exceed the machine capacity, and the
processing time of a batch is equal to the longest time among all the jobs in the batch. Moreover, this paper attempts to
schedule jobs on a single batch-processing machine to minimize makespan. A joint GA+DP algorithm is proposed involving two
stages: (1) the formation of job sequence by genetic algorithm operators, and (2) the formation of batches by a dynamic programming
algorithm. Computational experiments are given to examine the performance of the proposed algorithm. The experimental results
indicate that the joint GA+DP approach has well improved on all instances with respect to solution quality and runtime. 相似文献
106.
Guangxin Wu Jieyu Zhang Yuling Ren Guoyang Li Xiaochun Wu Qian Li Kuochih Chou 《Metallurgical and Materials Transactions A》2012,43(6):2012-2017
First-principles method was performed to predict the effect of Ti addition on thickness and adhesion of 55 pct Al-Zn-1.6 pct
Si coating. The results of optimized geometric configurations, total energy, and charge distributions for the Ti substitution
in Fe2Al5 and FeAl3 phases indicated Ti will grab electronic charges from Al atoms, form bonds with neighboring Al, which
will reduce the growth of Fe-Al intermetallic layers, and finally enhance the adhesion of the coating/substrate. Furthermore,
experiments were performed to validate the prediction results of first-principles successfully. 相似文献
107.
Hung‐Chieh Lo Po‐Yi Chou Chun‐Chieh Huang Po‐Jui Chen Shih‐Meng Hsu 《Water and Environment Journal》2014,28(3):442-448
Drawing from the lessons learnt from the Fukushima nuclear disaster in Japan, the assessment of subsurface environmental hazard around nuclear power plants has emerged as a critical task. Consequently, aiming to better understand the possible environmental impact of radiation leaks into the groundwater, a prescreening programme was initiated in 2011 by the Taiwanese government. As part of this programme, this study conducted various borehole prospecting techniques to identify in situ hydrogeological characteristics at Chin‐Shan Nuclear Power Plant. Borehole electrical log, sonic log and temperature/conductivity log were conducted to explain the regional lithologic conditions and permeability of the formation. In conjunction with this, the interwell tracer and pumping test was carried out to simultaneously determine the hydraulic parameters. In our opinion, the implementation of such in situ end‐to‐end investigations is essential in interpreting in situ fluid and solute transport dynamics prior to programming any numerical scheme for early warning, vulnerability assessment and regular monitoring of a nuclear power plant site. 相似文献
108.
The change of morphology of poly(3‐hexylthiophene) (P3HT) film as a result of blending with [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) was studied using a freeze‐dry method. A porous structure was observed as the P3HT/PCBM solution was freeze‐dried. The pore size decreased as the proportion of PCBM increased in the P3HT/PCBM blended film. Additionally, the freeze‐dried P3HT/PCBM film was more resistant to the formation of PCBM crystals than that prepared by a spin‐coating method during the thermal annealing process. Homogeneous distribution of PCBM in the freeze‐dried P3HT/PCBM film was the main reason for the reduction of large PCBM crystal formation. Copyright © 2011 Society of Chemical Industry 相似文献
109.
The better compression rate can be achieved by the traditional vector quantization (VQ) method, and the quality of the recovered image can also be accepted. But the decompressed image quality can not be promoted efficiently, so how to balance the image compression rate and image recovering quality is an important issue. In this paper, an image is transformed by discrete wavelet transform (DWT) to generate its DWT transformed image which can be compressed by the VQ method further. Besides, we compute the values between the DWT transformed image and decompressed DWT transformed image as the difference matrix which is the adjustable basis of the decompressed image quality. By controlling the deviation of the difference matrix, there can be nearly lossless compression for the VQ method. Experimental results show that when the number of compressed bits by our method is equal to the number of those bits compressed by the VQ method, the quality of our recovered image is better. Moreover, the proposed method has more compression capability comparing with the VQ scheme. 相似文献
110.
Abstract The effect of geometric parameter on laminar mixed convection in the entrance region of shrouded arrays of heated rectangular blocks is approached numerically for large Prandtl number fluid. The problem considered is related to convective cooling of electronic components mounted on horizontal circuit boards. Typical development of streamline and isotherm, block wall temperature distribution, and local Nusselt number are presented. It is found that the secondary flow leads to a significant enhancement in heat transfer. The multiple eddies above the block, induced by the combined geometric and buoyancy effect, lead to a more uniform block wall temperature distribution and then reduce the magnitude of the highest wall temperature. 相似文献