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排序方式: 共有120条查询结果,搜索用时 15 毫秒
1.
介绍了对电站发动机组凝汽器进行状态监测和故障诊断的技术诊断自动化系统的研究和实现,实践证明,开发的系统对改善凝汽器性能、提高电站整体性能具有重要意义。  相似文献   
2.
蒸汽渗透是一种新型膜分离技术。本文以脱除丙烯中微量水份为目的,对壳聚糖复合膜的制备和分离性能进行了探索。首先研制了蒸汽渗透膜,选用聚砜中空纤维支撑膜,采用涂布法制备了壳聚糖复合膜。其次,考察了制膜液浓度,交联剂用量,热处理温度,时间等因素对复合膜蒸汽渗透性能的影响。  相似文献   
3.
针对汽液两相流升压装置利用经验模型计算的过程中,仅能对出口压力进行计算,且计算值与实验值有较大误差的弱点,提出了用直接接触凝结(DCC)的理论求解汽液两相流的一维理论模型。计算升压装置的最大出口压力,分析其他参量的变化规律。结果表明,汽液两相流在凝结激波前为泡沫流,在凝结激波后完全凝结成单相水的情况下,升压装置的出口压力达到最大值。  相似文献   
4.
本文采用孔板及均速管组合形式,对汽-水两相流的流量及干度的双参数测量进行了实验研究。实验结果表明,这种测量方法可以满足高干度湿蒸汽测量的要求,具有很好的工业适用性。  相似文献   
5.
Recent studies have paid more attention to how position-generated social capital varies by an individual’s characteristics, and less to how geographical distributions of occupations may constrain position-specific connections. By integrating two national surveys from the United States, we differentiate the extent to which individual social capital fluctuates by occupational compositions at the county, metropolis, and state levels. Multilevel analyses show that when more people at all three levels work in education, training, and library occupations, residents have a greater chance to gain access to professional-type resources. Similar spatial effects on farming and production resources, however, are more apparent at the county level. Not only does the association between individual social capital and local occupational structures vary across different occupations, but the magnitude of such spatial effects also differs by the scope of the geographical areas. The findings underscore how contextual factors and geographical location may contribute to building occupation-specific network resources.  相似文献   
6.
The study investigates inequalities in access to social capital based on social class origin and immigration background and examines the role of transnational ties in explaining these differences. Social capital is measured with a position generator methodology that separates between national and transnational contacts in a sample of young adults in Sweden with three parental backgrounds: at least one parent born in Iran or Yugoslavia, or two Sweden‐born parents. The results show that having socioeconomically advantaged parents is associated with higher levels of social capital. Children of immigrants are found to have a greater access to social capital compared to individuals with native background, and the study shows that this is related to transnational contacts, parents’ education and social class in their country of origin. Children of immigrants tend to have more contacts abroad, while there is little difference in the amount of contacts living in Sweden across the three groups. It is concluded that knowledge about immigration group resources help us predict its member's social capital, but that the analysis also needs to consider how social class trajectories and migration jointly structure national and transnational contacts.  相似文献   
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A new two-parameter distribution, the gamma-Maxwell distribution, isproposed and studied. We generate the new distribution using the gamma-G generator of distributions. The proposal distribution can be seen as an extension of the Maxwell distribution with more flexibility in terms of the distribution asymmetry and kurtosis. We study some probability properties, discuss maximum-likelihood estimation and present a real data application indicating that the new distribution can improve the ordinary Maxwell distribution in fitting real data.  相似文献   
9.
The importance of random number generators has increased over the years. This follows from the fact that contemporary research methods rely more and more on simulation and the increased importance of encryption technology. The output of a random number generator is created by either an algorithm or a physical device. The most popular method for random number generation is through the use of an algorithm. This article presents a new category of physical random bit generator that is packaged by several manufacturers. A statistical analysis of the output from the generators is given.  相似文献   
10.
介绍在Windows环境下用BorlandC++3.1开发的通用函数图形发生器的结构和功能,讨论了实现中的表达式求值算法和图形生成算法。FGG的主要特点是,对输入的任意一元、二元函数表达式可直接生成对应的二维和三维图形。FGG作为CAI写作工具的支撑软件,可用于CAI课件的开发及演示。  相似文献   
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