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41.
某微型车车架开裂原因分析与改进措施 总被引:1,自引:0,他引:1
针对微型车车架在路试过程中纵梁撕裂的问题,从结构受力特点出发并结合相关的有限元分析结果认为:结构受力不合理及局部的细节设计上的缺陷导致了纵梁的开裂。根据实际工艺要求,提出了改进措施,实践证明措施是有效的。 相似文献
42.
43.
张春霞 《福建农业大学学报(哲学社会科学版)》2007,10(3):1-6
围绕“新”进行深入的分析,对区域发展战略的历史进行对比,分析海峡西岸经济区建设的新战略,提出海峡西岸经济区新农村建设具有的新内涵,最后阐述了海峡西岸社会主义新农村建设的特色。 相似文献
44.
Gin Swen Ham Elise Lahaye Massimiliano Rosso Aurelie Moulins Ellen Hines Paola Tepsich 《水产资源保护:海洋与淡水生态系统》2021,31(8):2257-2277
- Mediterranean fin whales aggregating in the Pelagos Sanctuary in summer to feed are exposed to vessel collision risk, particularly from high-speed ferries.
- This study developed models to predict summer fin whale distribution using a generalized additive model (GAM) and MaxEnt, with the aim of providing a tool to identify potential high whale–ferry collision risk areas along ferry routes within the Pelagos Sanctuary during summertime.
- Models were trained using sightings data collected in the summer months of 2009–2018 on board ferries crossing the central area of the Pelagos Sanctuary. Environmental predictors were bathymetry and mean sea surface chlorophyll concentration of the annual spring bloom period.
- The predictive ability of GAM and MaxEnt was assessed using existing knowledge of summer fin whale distribution in the region. GAM (deviance explained = 20.2%) predictions matched documented distributions more closely than that of MaxEnt, with highest predicted fin whale occurrence in deep offshore waters (>2000 m) encompassing the central north-western and western regions, and in the south-eastern region, consistent with known fin whale habitats within the Pelagos Sanctuary. Inter-annual variability was evident, influencing collision risk areas.
- Collision risk was estimated as a function of the overlap between the predicted probability of fin whale occurrence and ferry density estimated from Automated Identification System data. Ferry routes that cross the northern and eastern regions of the Pelagos Sanctuary presented relatively higher collision risk.
- Areas with changes in risk intensity between the years were temporally and spatially dynamic: some appeared intermittently throughout the study period while others persisted over consecutive years or recurred in different years.
- Due to the vastness of the Pelagos Sanctuary, vessel speed reduction maybe a more practical measure to manage collision risk than re-routing shipping lanes. A combination of Seasonal Management Areas and Dynamic Management Areas approaches could be adopted for high-risk areas.
45.
Prevention and treatment of intraoperative hypoxemia in horses is difficult and both efficacy and safety of therapeutic maneuvers have to be taken into account. Inhaled salbutamol has been suggested as treatment of hypoxia in horses during general anesthesia, due to safety and ease of the technique. The present report describes the occurrence of clinically relevant unwanted cardiovascular effects (i.e. tachycardia and blood pressure modifications) in 5 horses undergoing general anesthesia in dorsal recumbency after salbutamol inhalation. Balanced anesthesia based on inhalation of isoflurane in oxygen or oxygen and air and continuous rate infusion (CRI) of lidocaine, romifidine, or combination of lidocaine and guaifenesine and ketamine was provided. Supportive measures were necessary to restore normal cardiovascular function in all horses but no long-term adverse effects were noticed in any of the cases. 相似文献
46.
何福平 《福建农业大学学报(哲学社会科学版)》2005,8(4):11-14
闽台农业在资金、技术、市场、人力资源、自然资源、区域空间等方面具有很强的互补性.建立健全闽台农业合作机制,加强闽台农业合作沟通协商、产业及产品产销对接、人力资源和技术交流,有效化解风险,形成闽台全面农业合作体系,有利于实现闽台农业合作双赢,为海峡西岸经济区建设打下坚实基础. 相似文献
47.
介绍了在曲柄压力机上切边冲孔的复合模结构设计、工作原理及装配和调试要求等. 相似文献
48.
渔船碰撞事故责任分析中应注意的若干问题 总被引:1,自引:0,他引:1
随着海洋渔业的发展,渔船数量不断增多,船舶间碰撞事故的发生也就难以避免了。渔港监督部门作为主管机关在受理碰撞事故后,必然要进行责任分析,明确双方当事船舶的责任分摊。本文依据《1972年国际海上避碰规则》,提出了渔船碰撞事故责任分析中应注意的若干问题,以便有关部门参考。 相似文献
49.
切沟对沟岸地土壤水分的影响 总被引:1,自引:0,他引:1
In order to preliminarily look at rules for soil moisture changes in the bank of the gully and to provide some recommendations for vegetative restoration in gully bank regions in the Loess Plateau, changes of soil moisture with depth and distance to the gully edge and their dynamic changes with time were observed to study the soil water characteristics in the bank of the gully. The results showed that soil water content increased with increasing distance from the gully edge, whereas for the same time period, the closer the distance to the gully wall, the greater the water loss; and that the influential distance of side evaporation decreased as depth increased. 相似文献
50.