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排序方式: 共有1785条查询结果,搜索用时 15 毫秒
1.
天楼地枕水电公司为实现水电站"无人值班,少人值守"的目标,对水电站进行了综合自动化改造,论述了该自动化系统的结构特点及实施情况. 相似文献
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根据加油站效益的增长关系到成品油销售企业生存与发展的重要地位,以及加油站站长职能逐步由管理向经营、经理人转变的实际情况,指出做好加油站的经营管理工作,最大限度地调动加油站站长的工作积极性是企业必须认真研究解决的问题。阐述了调动站长积极性应做好如下工作:建立优胜劣汰的站长选聘机制;赋予站长应有的管理权力;站长实行“特岗特薪”,体现站长责、权、利的统一;制定公平、客观的业绩考核激励机制;强化站长培训,提高站长的综合素质和专业技术水平。 相似文献
4.
双光子Jaynes-Cummings模型的亚泊松光子统计特性研究 总被引:4,自引:1,他引:3
本文利用量子电动力学理论和缀饰原于方法,对双光子James-Cummings模型中单模激光场的稳态亚泊松光子统计性质进行了系统研究。结果表明:激光上能级相对泵浦参量Xa具有一个确定的阈值Xat;当Xa>Xat时,光场呈现亚泊松光子统计;而当Xa>>Xat时,光场将呈现出深度且完全恒定的亚泊松光子统计。 相似文献
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Jack E. Pennington 《Applied Intelligence》1992,2(2):155-162
A popular conception of the evolution of remote manipulation is a progression from teleoperation to telerobotics and then to robotics. This is logical because in going from teleoperation to robotics there would appear to be a continuous decrease in manned workload, an increase in system complexity, and an increase in the amount of intelligence in the automated system. During the past 10 years NASA Langley Research Center (LaRC) has been involved in all three areas. The decision on which system is most suitable for a task depends not only on the task, but on the allocation of responsibility for intelligence or high level control. The operator may be responsible for all intelligence and control functions, they may be shared between the operator and the automated system, or they may be performed by an autonomous system. This paper discusses some of the experiences in each area in applications related to possible space tasks and some of the lessons learned. 相似文献
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The viscoelastic and peeling properties of polybutadiene/tackifying resin compatible blends have been studied in detail. Viscoelastic properties have been described through the variations of the complex shear modulus, G*(ω), as a function of frequency, ω and peeling properties through the variations of peeling force (F) as a function of peeling rate (V).
After showing the objective character of the peeling curves obtained, the variations of the peeling force and peeling geometry have been studied as a function of volume fraction of the tackifying resin.
In this first paper, the analysis is focused on the first domain of the peeling curves, i.e. the cohesive fracture region. In this region, the peeling properties have been related to the viscoelastic properties in the terminal region of relaxation. It is shown that the longest relaxation time, τo, is a reducing parameter of the peeling curves, so a peeling master curve-which is independent of temperature, resin volume fraction and polymer molecular weight-may be defined. Furthermore, the variations of the test geometry as a function of peeling rate have been investigated: the variations of the radius of curvature of the aluminium foil have been analyzed with respect to the viscoelastic behavior of the adhesive, which in fact governs the test geometry.
A detailed analysis of all these features leads to a model which allows one to calculate the peeling curves in the cohesive domain from the adhesive formulation. 相似文献
After showing the objective character of the peeling curves obtained, the variations of the peeling force and peeling geometry have been studied as a function of volume fraction of the tackifying resin.
In this first paper, the analysis is focused on the first domain of the peeling curves, i.e. the cohesive fracture region. In this region, the peeling properties have been related to the viscoelastic properties in the terminal region of relaxation. It is shown that the longest relaxation time, τo, is a reducing parameter of the peeling curves, so a peeling master curve-which is independent of temperature, resin volume fraction and polymer molecular weight-may be defined. Furthermore, the variations of the test geometry as a function of peeling rate have been investigated: the variations of the radius of curvature of the aluminium foil have been analyzed with respect to the viscoelastic behavior of the adhesive, which in fact governs the test geometry.
A detailed analysis of all these features leads to a model which allows one to calculate the peeling curves in the cohesive domain from the adhesive formulation. 相似文献
8.
王加龙 《现代塑料加工应用》2003,15(5):17-19
研究了采用过氧化物DCP、将DCP制成母料、在DCP母料中加入分散剂、在加入分散剂的母料中再加入助交联剂MAH(顺丁烯二酸酐)这4种条件下LDPE的交联情况,讨论了DCP的加入量对LDPE交联度的影响,同时讨论了交联度随交联时间的变化。 相似文献
9.
采用无毒、耐候性好、热稳定性高的颜料制得PP-R、PP-B管材料专用色母粒,考察了色母粒对PP-R、PP-B管材料力学性能、耐热性、耐光性、卫生安全性的影响。结果表明:该色母粒对PP-R、PP-B管材专用料的力学性能影响不大,采用该色母粒无需改变PP-R、PP-B管材的生产工艺。 相似文献
10.
氟化物熔盐共电沉积制备Gd-Mg中间合金研究 总被引:3,自引:0,他引:3
以混合Gd2O3-MgO为原料,在GdF3-LiF-BaF2-CaF2氟化物熔盐体系中研究一步法共电沉积制备了Gd-Mg中间合金,探讨了电解质成分、原料Gd2O3-MgO中Gd/(Gd+Mg)、电解温度等对电流效率的影响.研究表明,共电沉积得Gd-Mg中间合金以GdMg相存在,成分均匀;随电解质成分GdF3含量、原料Gd2O3-MgO中Gd/(Gd+Mg)、电解温度、电流密度的提高,电流效率均先升后降;当电解质GdF3含量为85wt%、原料Gd2O3-MgO中Gd/(Gd+Mg)为86wt%、电解温度为1 050℃、体电流密度0.10 A/cm3时,电流效率最高达到80%. 相似文献