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131.
本系统基于可编程序控制嚣(PLC)本身具有的逻辑和计算功能及抗干扰和抗震性能强的特点,实现煤矿配煤装丰系统的自动化控制。系统软件采用模块化编程。程序用梯形图语言编写。系统性能稳定,运行费用低,运行可靠。  相似文献   
132.
介绍了混凝土工程施工(拌制、运输、浇筑和养护)的全过程,并重点阐明了在施工过程的各个环节中应注意的问题,从而达到提高工程质量的目的。  相似文献   
133.
讨论一种受到一般随机干扰的汇率模型,介绍随机循环的含义及定理,使用随机李雅普诺夫函数得到了在一定的条件下受到各种随机干扰的实际汇率的波动范围。  相似文献   
134.
本文以水温垂线分布和水体物质浓度平面分布的现场实测资料为基础,考虑了风对浅水湖泊的显著效应,通过密度福氏数的分析,阐明了西湖中的小南湖换水时水体运动特性及其所属类型.在此基础上,导得物质浓度变化的计算式,并用实际资料予以验证,从而对改善湖水水质的经济合理换水方式进行了原则探讨.  相似文献   
135.
本文对塔径90mm,塔高1980mm,有挡板的振动筛板萃取塔中连续相轴向混合和分散相塔藏量进行了实验研究.实验体系为煤油一水.通过实验,分别得到了连续相轴向混合系数和分散相塔藏量的关联式.  相似文献   
136.
用石英砂-水(连续相)-煤油(分散相)系,在直径0.152m的开式涡轮转盘塔中进行了实验,证明该塔用于含固量较高的液-液-固系是可行的。研究了转速、隔室高度、定环开孔直径和各相表观流速对固相滞留率及轴向混合的影响,给出了固相滞留率及返流此的关联式。  相似文献   
137.
During the last 13 years, a dialogue has been conducted in the Critical Systems literature on the subject of choice betwen methods. However, in the late 1980s and early 1990s, researchers went in two separate directions. One direction involved an exploration of the “creative design of methods.” This is when the problem situation is understood in terms of a series of systemically interrelated research questions, each of which might need to be addressed using a different method, or part of a method. A synthesis is generated that allows each individual research question to be addressed as part of a whole system of questions. The other research direction involved the development of “Total Systems Intervention” (TSI), a meta-methodology that, amongst other things, encourages the creative exploration of the problem situation prior to the choice of methods. One of the latest innovations in TSI is a theory of the “oblique” use of methods. This is the use of methods for purposes other than those they were originally designed for. However, it is argued here that all the case studies that have been subject to an “oblique” interpretation can be better explained if they are seen as examples of the creative design of methods. We can therefore bring together the two strands of research that have hitherto been pursued separately in the Critical Systems literature. it is suggested that TSI can be enhanced by an understanding of the creative design of methods because the latter allows us to explain the purposive, flexible, and responsive way in which TSI is most successfully used in practice.  相似文献   
138.
混凝土是目前使用非常广泛的工程结构材料。从混凝土生产的角度分析了影响混凝土质量的各种因素,提出了提高混凝土质量的建议与措施。  相似文献   
139.
讨论费米子动力学对称模型(FDSM)中κ-激发模式中heritage混合的计算,给出混合heritage的哈密顿,讨论模型空间基矢的选取及标记,并给出哈密顿算符以及E2跃迁算符矩阵元的具体表达式。  相似文献   
140.
This paper is concerned with the adjustment processes within a potential European monetary union and looks in particular at permanent asymmetric shocks that require an adjustment in a country's (or region's) real exchange rate. We first consider some of the implications of EMU and the question of asymmetries within the European economy. The presence of asymmetries and, in particular, different institutional structures in labour markets is a potential source of tension within a union and it could make a union difficult to sustain. However, automatic adjustment processes will be at work within a monetary union as a result of changes in relative price levels, which change real exchange rates, and also as a result of changes in wealth stocks. We use our econometric world model, NIGEM, to investigate the effects of asymmetric fiscal expansions and real exchange rate misalignments within a monetary union. In order to quantify the effects of such permanent asymmetric shocks we have introduced wealth into our model. Our simulations suggest that the principal impact of the fiscal expansion on both output and the price level will occur within the country in which the expansion occurs. Short-term gains are crowded out in the medium term, and while monetary union reduces crowding out in the short term, it increases the rate at which crowding out occurs thereafter. We also analyse the effects of real exchange rate misalignments and find that the processes of adjustment may be very protracted. This could cause strain on the union as adjustment costs are shared unequally.  相似文献   
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