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美国公共行政理论中管理主义之哲学基础与内在逻辑
美国公共行政理论中的管理主义范式经历了萌芽、形成、拓展和成熟四个发展阶段.实证主义是管理主义的哲学基础,因为实证主义为管理主义提供了方法论基础,而管理主义是实证主义在管理领域的具体应用.美国公共行政理论中的管理主义是在与宪政主义的争论中得以发展和完善的,其理论体系由单一化、片面化逐渐走向多元化、系统化;理论研究由注重经济、效率价值转向既注重经济、效率价值,又兼顾人本价值,这是美国公共行政理论中管理主义发展的内在逻辑.刘耀东,施雪华 - 中国人民大学学报文章来源: 万方数据 -
There is less research on vertical sculptured grinding technology.Especially in high vertical surface grinding process with the cup abrasive wheel,the thermal damage is prone to happen and undermine the grinding surface integrity.This problem limits to improve the grinding efficiency and the grinding ratio greatly.Through the analysis of vertical surface grinding process and features in depth,this paper revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel.Based on the previous research achievements,the grinding experiments on TC4(Ti-6Al-4V)and GH4169 are carried out utilizing the self-inhaling internal cooling wheel.The experimental results show that the self-inhaling internal cooling wheel can efficiently reduce the grinding surface temperature.Moreover,the inherent mechanism of reducing the grinding temperature using the internal cooling method is revealed.Meanwhile,under the same grinding conditions,the grinding ratio during the experiments on GH4169 using self-inhaling internal cooling method is about 3 times as high as using conventional external cooling method.And the grinding forces can be reduced by about 20%.This research revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel,which provides theoretical basis for the design and application of self-inhaling internal cooling wheel.At the same time,an efficient and non-invasive surface grinding method of TC4 and GH4169 is presented.- 中国机械工程学报文章来源: 万方数据
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Many researches on drilling force and temperature have been done with the aim to reduce the labour intensiveness of surgery, avoid unnecessary damage and improve drilling quality. However, there has not been a systematic study of mid- and high-speed drilling under dry and physiological conditions(injection of saline). Furthermore, there is no consensus on optimal drilling parameters. To study these parameters under dry and physiological drilling conditions, pig humerus bones are drilled with medical twist drills operated using a wide range of drilling speeds and feed rates. Drilling force and temperature are measured using a YDZ-II01 W dynamometer and a NEC TVS-500 EX thermal infrared imager, respectively, to evaluate internal bone damage. To evaluate drilling quality, bone debris and hole morphology are observed by SEM(scanning electron microscopy). Changes in drilling force and temperature give similar results during drilling such that the value of each parameter peaks just before the drill penetrates through the osteon of the compact bone into the trabeculae of the spongy bone. Drilling temperatures under physiological conditions are much lower than those observed under dry conditions, while a larger drilling force occurs under physiological conditions than dry conditions. Drilling speed and feed rate have a significant influence on drilling force, temperature, bone debris and hole morphology. The investigation of the effect of drilling force and temperature on internal bone damage reveals that a drilling speed of 4500 r/min and a feed rate of 50 mm/min are recommended for bone drilling under physiological conditions. Drilling quality peaks under these optimal parameter conditions. This paper proposes the optimal drilling parameters under mid- and high-speed surgical drilling, considering internal bone damage and drilling quality, which can be looked as a reference for surgeons performing orthopedic operations.XU Linlin,WANG Chengyong,JIANG Min,HE Huiyu,SONG Yuexian,CHEN Hanyuan,SHEN Jingnan,ZHANG Jiayong - 中国机械工程学报(英文版)文章来源: 万方数据
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论《湘报》对近代传媒合法性论证的逻辑路径及其特征
《湘报》对近代传媒进行合法性论证时,以提高国家竞争力,应付民族危机为核心,其逻辑路径从如下三个方面展开:危机时刻的情境定义、民智愚昧的归因分析与广办新报的求解策略.这种合法性论证逻辑,具有政治化思维、功能论文明观与志士精神的特征,引发了知识界的巨大反响,掀起了办报高潮.但因忽视民众要求,学理系统性不强,深刻影响了近代传媒在中国的出场路径与面貌形态.阳海洪 - 国际新闻界文章来源: 万方数据 -
河北省石津灌区总干渠闸控系统的设计与构建
对河北省石津灌区总千渠闸门控制系统构建的重要性和必要性进行了分析,针对灌区具体情况提出了闸控系统的设计原则,选择了主从结构、分布式实时监测方式,闸门的控制选择了现地控制、远程监测模式,可以实现多重控制手段来保证系统安全有效的运行.文章对系统进行了详细的总体设计,并分别阐述了现地监控站的结构组成、闸控系统应实现的功能和软件的性能、可实现功能等内容.总结了系统建设经验和今后系统运行维护时的重点,为同类型灌区提供了一定的经验和借鉴.杨国华,李得龙 - 南水北调与水利科技文章来源: 万方数据 -
WHO西太区与世界中医药学会联合会中医名词术语国际标准比较研究:内科疾病(五)
肝着liver fixity:a diseased condition arisingwhen qi and blood of the liver meridian becomedepressed and stagnant The so-called肝着,used first in Synopsis ofGolden Chamber (《金匮要略》),describes a path-ological condition caused by stagnation of qi andblood in the liver and characterized by thoracic李照国,刘瑞强 - 中西医结合学报文章来源: 万方数据 -
基于PLC和变频技术的中央空调控制系统改造设计
基于节能减排的目的,对中央空调控制系统实施改造.首先分析了中央空调系统的运行现状,阐述了中央空调系统的构成和变频节能原理,继而采用PLC和变频控制相结合的温差法控制方案对原有系统进行改造,给出了设计方案,进行了变频器的参数设置,并进行了节能分析.最后指出了中央空调采用变频调速控制具有较好的实用价值和发展前景.张涛,张丽,尚希 - 电机与控制应用文章来源: 万方数据

