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131.
132.
Error-resilient video communication over lossy packet networks is often designed and operated based on models for the effect of losses on the reconstructed video quality. This paper analyzes the channel distortion for video over lossy packet networks and proposes a new model that, compared to previous models, more accurately estimates the expected mean-squared error distortion for different packet loss patterns by accounting for inter-frame error propagation and the correlation between error frames. The accuracy of the proposed model is validated with JVT/H.264 encoded standard test sequences and previous frame concealment, where the proposed model provides an obvious accuracy gain over previous models. 相似文献
133.
Ying Gao Nina Nevala Neil J. Cronin Taija Finni 《European Journal of Sport Science》2016,16(6):747-754
Sit–stand workstations offer a potential strategy to reduce prolonged occupational sitting. This controlled intervention study examined the effects of an environmental intervention on occupational sedentary time, musculoskeletal comfort and work ability, and the usability of sit–stand workstations in office work via a self-reported questionnaire. The intervention group (n?=?24) used sit–stand workstations during the 6-month intervention period, and the control group (n?=?21) used traditional sitting workstations. The results showed that working at sit–stand workstations can reduce sitting time significantly compared to control workstations (?6.7% vs. 5.0%, p?=?.019), which is reallocated mostly to standing (r?=??0.719, p?.001). Sit–stand workstations improved perceived musculoskeletal comfort in the neck and shoulders (p?=?.028), as well as work ability (p?=?.022). The majority of intervention subjects rated sit–stand workstation adjustability as good (83.3%), and 75.0% were satisfied with the workstation. About 41.7% of the intervention participants, who were exclusively female, used the sit–stand function on a daily basis. While the environmental change alone was effective, it is likely that promoting the daily use of sit–stand workstations with counselling would lead to even more substantial positive effects. 相似文献
135.
通过分析农民工工伤保险制度供给的公共政策议程背景、经济失衡背景以及现实问题背景三大背景,从农民工、政府及企业三方契约参与者理性选择角度,展现农民工社会保险制度供给中应有的基本战略认识。 相似文献
136.
光荣革命后的很长时期里,土地贵族和金融寡头通过控制议会而掌握国家政权;到十九世纪初,随着工业化的推进,资产阶级财富增多,中等阶级和工人阶级力量壮大,参政意识觉醒,他们要求改革贵族寡头把持国家政权的旧制,分享权力。1832年议会改革就是在这样的背景之下产生的,工业革命所带来的经济和社会的变化对旧制度的反叛是改革的根本原因。面对澎湃兴起的改革浪潮,统治集团的审时夺势和适时退让是改革法案最终生效的关键。 相似文献
137.
氢化丁腈橡胶的应用与研究进展 总被引:8,自引:0,他引:8
本文评述了氢化丁腈橡胶(HNBR)的应用及进展,指出了我国发展氢化丁睛橡胶的潜力。 相似文献
138.
中国共产党走过了八十多年光辉战斗历程,面对新世纪新阶段、新任务,必须按照“三个代表”重要思想的要求,全面推进党的建设新的伟大工程,必须坚持不懈地开展反腐败斗争,加强党风廉政建设,构建强有力的权力制衡机制,从体制上铲除腐败。只有这样才能增强党的凝聚力、战斗力、创造力,实现中华民族的伟大复兴。 相似文献
139.
Chinese Meishan and Jiangquhai pigs are two of the most prolific pigs in the world, but their growth rate is lower than that of Duroc, Landrace and Pietrain pigs. It is suggested that growth rate is regulated by growth hormone. The objective of the current study was to analyze the porcine growth hormone (pGH) gene polymorphisms based on the polymerase chain reaction restriction fragment-length polymorphism method (PCR-RFLP) for three western meat-type breeds (Duroc, Landrace and Pietrain) and two local Chinese pigs (Meishan and Jiangquhai). Five polymorphic restriction sites were detected with the ApaI, MspI, BspI and HhaI restriction enzymes in two amplified fragments (605 bp, -119 to +486; 506 bp, +206 to +711). Breed difference was found only in the 506 bp fragment. There was no difference in allelic frequencies of BspI and HhaI restriction sites among the five breeds (P>0.05). Landrace and Meishan pigs lacked allele G3 of MspI site. The allele G3 frequency of restriction MspI site of the 506 bp fragment in Pietrain pigs was higher than that in Duroc and Jianquhai pigs (P<0.001). For ApaI site, the Meishan pigs lacked allele G1; no difference was found in allelic frequencies among Pietrain, Duroc, Landrace and Jiangquhai pigs (P>0.05). This new and rapid PCR-RFLP typing method is an attractive tool for analysis of porcine growth hormone gene restriction sites. The differences in MspI and ApaI restriction sites may explain the growth difference between the foreign meat-type breeds above mentioned and local Chinese pigs. 相似文献
140.