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为提高我国空中交通管制(简称"空管")的服务质量,弥补现有空管服务质量评价指标体系在构建上的局限性,在原体系的基础上进一步完善了我国空管服务质量评价指标体系。首先,从空管服务过程分析了影响空管服务质量的主要因素。然后,基于质量管理体系中的过程方法和戴明循环理论,建立空管服务质量管理模型。接着,以该模型为基础,选取运行安全、运行效率、管理效能和文化建设四个关键指标,构建了空管服务质量评价指标体系。最后,以厦门空管站的空管服务评价体系指标设置为例,对所建指标体系进行验证。结果表明,该评价体系具有一定的客观性和科学性。 相似文献
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Highly porous ultrafine electrospun scaffolds, gelatin/poly(L-lactic acid) (PLLA) and chitosan/PLLA were prepared by blending gelatin and PLLA, chitosan and PLLA respectively. The biocompatibilities of these scaffolds were assessed by attachment, proliferation and viability of cells on them. The results indicated that over 30% WI-38 cells could attach to the gelatin/PLLA and chitosan/PLLA scaffolds at 2 h after seeding, while the attachment of the cells was only 15% on PLLA scaffolds. Both gelatin/PLLA and chitosan/PLLA scaffolds also exhibited a very good ability for proliferation of WI-38 cells. Cell growth on the gelatin/PLLA and chitosan/PLLA scaffolds showed dramatic improvement, indicating a much better biocompatibility in the blends contributed by gelatin and chitosan. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay also demonstrated gelatin/PLLA showed better ability to enhance the growth and functions of the cells. These assays suggest that the electrospun gelatin/PLLA and chitosan/PLLA scaffolds are promising biomaterials with great biocompatibility for the development of skin tissue engineering. 相似文献
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随着近几年西气东输、川气东送工程的建成,天然气已成为我国重要能源之一.受国家科技部等多个部委推动,天然气汽车已经作为清洁汽车推广.我国的CNG(压缩天然气)客车制造水平因此也迈上一个新的台阶,走出国门,出口到很多CNG资源比较丰富的发展中国家;但是,每个国家对CNG客车的要求、国家资源现状及文化背景等都不尽相同,所以要想出口的客车在当地良好运行,必须对当地的法规、标准、资源现状等了解清楚.笔者以安凯出口巴基斯坦的一款CNG客车为例,谈谈该款客车的燃气系统设计. 相似文献