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941.
H.264/AVC is the latest video coding standard adopting variable block size motion estimation (VBS-ME), quarter-pixel accuracy,
motion vector prediction and multi-reference frames for motion estimation. These new features result in much higher computation
requirements than previous coding standards. In this paper we propose a novel most significant bit (MSB) first bit-serial
architecture for full-search block matching VBS-ME, and compare it with systolic implementations. Since the nature of MSB-first
processing enables early termination of the sum of absolute difference (SAD) calculation, the average hardware performance
can be enhanced. Five different designs, one and two dimensional systolic and tree implementations along with bit-serial,
are compared in terms of performance, pixel memory bandwidth, occupied area and power consumption.
相似文献
Philip H. W. Leong (Corresponding author)Email: |
942.
943.
944.
Ackermann DM Smith B Wang XF Kilgore KL Peckham PH 《IEEE transactions on bio-medical engineering》2008,55(4):1365-1373
Optical telemetry has long been an option for transcutaneous data transfer and has been used in various types of implanted systems. This telemetry modality and the efficiency of these optical links are becoming ever more important as higher bandwidth sources such as cortical recording arrays are being implemented in implanted systems. The design of the transmitter-skin-receiver interface (the "optical interface") is paramount to the operation of a transcutaneous optical telemetry link. This interface functions to achieve sufficient receiver signal power for data communication. This paper describes a mathematical analysis and supporting data that quantitatively describes the relationship between the primary interface design parameters. These parameters include the thickness of the skin through which the light is transmitted, the size of the integration area of the optics, the degree of transmitter-receiver misalignment, the efficiency of the optics system, and the emitter power. The particular combination of these parameters chosen for the hardware device will determine the receiver signal power and, therefore, the data quality for the link. This paper demonstrates some of the tradeoffs involved in the selection of these design parameters and provides suggestions for link design. This analysis may also be useful for transcutaneous optical powering systems. 相似文献
945.
Brian Dipert 《电子设计技术》2008,15(8):52-54,56,58,60
那些考虑把PC构件用于非PC设计的人最好记住:把宝押在PC技术上并非完全正确。在这个体系结构方向经验丰富的同行们已经了解这一点。一方面,人们将受益于PC行业特有的迅猛创新速度,以及全球每年销售的数亿台PC带来的低价格。另一方面,这样的创新速度还导致了迅猛的报废速度,这对于那些生产周期超过六个月的系统而言可能会有问题! 相似文献
946.
Brian L Carter Cho Y Lam Jason D Robinson Megan M Paris Andrew J Waters David W Wetter Paul M Cinciripini 《Nicotine & tobacco research》2008,10(7):1165-1169
This study explored some quandaries concerning craving and mood as motivators to smoke. Craving and negative mood have long been associated with day-to-day smoking as two of the primary motivational forces behind the maintenance of the behavior, as well as significant barriers in smokers' attempts to quit. Craving remains a clinically relevant phenomenon, with most smokers describing craving as a troublesome problem when quitting. Smokers' self-reports of negative mood, as an antecedent for smoking, are so robustly reported that many models of nicotine dependence have incorporated a critical role for negative mood in maintaining smoking behavior. However, several naturalistic studies that collected mood ratings with hand held computers from smokers in real time, just before smoking a cigarette, have provided scant evidence that negative mood plays a major role in motivation to smoke. No study to date has examined craving and mood data as a consequence of smoking, that is, collecting the same data immediately after smoking. This study used personal digital assistants (PDAs) to collect craving and mood data immediately before smoking, immediately after smoking, and at random times of day. Nontreatment seeking smokers (N = 72) carried a PDA for an average of 10 days while they recorded their smoking behavior. Results showed that craving and negative mood ratings were lowest immediately after smoking compared with immediately before smoking and at random times of day. These findings suggest that smokers may be at least partially motivated to smoke to lower their craving and improve their mood states. 相似文献
947.
Lindsey R Turner Robin Mermelstein Brian Hitsman Richard B Warnecke 《Nicotine & tobacco research》2008,10(1):201-212
We examined psychosocial mechanisms linking recent history of depression and subsequent short-term smoking cessation. Our sample included lower-educated women smokers who registered for a brief cessation intervention (registrant panel; n = 1,198), and a quasicontrol panel not participating in the intervention (population panel; n = 682). Women were surveyed by telephone every 6 months for a period of 2 years, measuring psychosocial variables (motivation, self-efficacy, perceived stress, and social support) and self-reported smoking status (7-day abstinence) at each point. In both panels, smoking rate and self-efficacy were strong independent predictors of subsequent cessation, but recent history of depression (as measured 6 months earlier) was not a significant predictor. However, among only the registrant panel, the effects of recent history of depression were significantly moderated by social support. Recently depressed women who had higher levels of perceived social support were as likely to quit subsequently as women who did not have a recent history of depression. The determinants of successful quitting among lower-educated women differ between those who seek assistance and those who do not. 相似文献
948.
Brian 《中国服装(北京)》2008,(12)
从2007年年底开始,就已经能看出visvim在08年的新动向了,中村世纪摆明了要以最高级的材质打造出一系列以环保为基础的产品,不论是物料及设计构造均达到极高的水准。先期发售的是FBT BEAR FOOT-FOLK,最大的特点是采用薄底设计。而一向都是visvim鞋款中舒适度数一数二的FBT本次更将其全面包装,鞋面上居然穿上了民族风的珠子,打造出最高水准的FBT鞋款。随后发售的鞋款也是FOLK series的成员。与前面提到的的BEARFOOT相似, 相似文献
949.
Brian 《中国服装(北京)》2008,(16)
Grun,是德语里绿色环保的意思,adidas最新推出了名为adidasGrun的环保企划。这个系列共有Nature、Recycled和Reground三大系列,眼前这双Campus.就是隶属于Regorund系列的头号主打鞋款.整双鞋采用不损害地球生态系统的天然无添加材料.比如竹子、麻布等物料制作,鞋垫采用Poli—Fresh可循环利用的Poliyou环保鞋原料创作, 相似文献
950.
Brian 《中国服装(北京)》2008,(20)
BAPE最新推出的皮制托盘可以说是BAPE近来的创意之作,可以让大家摆放杂物、锁匙等零碎物品,是非常实用的家居装饰物。米色皮革中心印有猿人图案,所采用的边角纽扣的组合设计十分方便存放,而且分别有大小两种规格,不过千万不要拿它当烟灰缸,否则烟灰会将皮革烧穿。而服饰方面,BAPE将过往一系列成功的图案设计再度逐一呈现在大家眼前,print tee有鲨鱼、老虎和熊猫头图案,zip—up也有猿猴脸迷彩、虎纹迷彩等等,长久以来喜欢BAPE的朋友可以借此“温故”。而新推出的牛仔裤作品主打工装风格,这也与今年秋冬季很多牛仔品牌的主打路线吻合,裤子采用painter denim的剪裁,其中hickory的竖条纹牛仔裤更加是工装“范儿’的标准装备。 相似文献