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91.
实现中、高职教育农科专业课程的有效衔接,是推动农科职业教育步入良性发展轨道的客观要求.本文对当前我国中、高等职业教育农科专业课程开发的现状进行分析,指出课程内容重复、专业技能倒挂等问题,并对建立中、高等职业教育农科专业课程的有效衔接机制进行阐述. 相似文献
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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
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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
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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
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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
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关于终身教育、终身学习与学习化社会理念的思考 总被引:56,自引:0,他引:56
倡导终身学习、构建终身教育体系与建立学习化社会的实践热潮正在我国掀起。但人们对于终身教育、终身学习以及学习化社会三大理念的理解和认识还有待深入。因此 ,从国际范围出发来深入地探讨、分析一下它们的“定义”、“要义”、“关系”、“初衷”等 ,对于尽可能走向理解的完善与认识的成熟而言 ,无疑是有所裨益的。 相似文献
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介绍了一种为中小学校进行教学仪器、器材、设备的订购、配备及管理的计算机管理软件系统,对其主要功能、数据库表、操作性能、用户界面、编程方法等作了扼要说明。 相似文献