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The airscrew included various propellers, fans, windmills and helicopter blades, etc. In an earlier paper [2], we suggested the Mathematical model of helicopter rotor airfoil. In this paper we shall concern ourselves with the problem of describing surfaces of the propellers.Instead of subdividing a surface into parts or "patches" we shall investigate ways to treat it as a whole. This method is simple to implement and computationally efficient.After making a series of researches, the mathematics model... The airscrew included various propellers, fans, windmills and helicopter blades, etc. In an earlier paper [2], we suggested the Mathematical model of helicopter rotor airfoil. In this paper we shall concern ourselves with the problem of describing surfaces of the propellers.Instead of subdividing a surface into parts or "patches" we shall investigate ways to treat it as a whole. This method is simple to implement and computationally efficient.After making a series of researches, the mathematics model of airplarce propellers has been established. A routine is made by using ALGOL-60 language according to the presented method. 空气螺旋包括螺旋桨、风车、风扇和直升机叶片等。在[2]里,我们提出了直升机旋翼桨叶的数学模型。本文探讨螺旋桨型面的描述问题。在这里,我们不是将一个型面分成许多块或“曲面片”,而是把它当作一个整体来处理。这种方法简单易行,计算有效。 经过初步探索,已经建立起飞机螺旋桨的数学模型,而且用Algol-60语言编写了计算程序。 The cost of the cupola burden would be the lowest under the conditions in which the computer is used to obtain the optimum burden ensuring chemical composition and characteristics of the molten iron. The article delivers the mathematics models, computer programme and something about the burden during the process and its analysis of the economical result. The process has been used in casting at HT15—33 in the Harbin Boiler Works, and the cost has been cut down by 11.41%. On July 14, 1980, approval was made... The cost of the cupola burden would be the lowest under the conditions in which the computer is used to obtain the optimum burden ensuring chemical composition and characteristics of the molten iron. The article delivers the mathematics models, computer programme and something about the burden during the process and its analysis of the economical result. The process has been used in casting at HT15—33 in the Harbin Boiler Works, and the cost has been cut down by 11.41%. On July 14, 1980, approval was made by the Harbin Institute of Science and Technology. The process is considered to be a new, advanccd and reasonable one with certain economical value, thus it should be recommended to spread. 用电子计算机实现最优化配料,是在保证铁水化学成分与性能的情况下使金属炉料的成本最低。文中介绍了此方法的数学模型。电子计算机程序,配料在生产中使用情况和经济效果分析。哈尔滨锅炉厂在HT15—33上使用,可降低成本11.41%。哈尔滨市科学技术委员会1980年7月14日对《用电子计算机实现冲天炉最低成本配料新方法》进行了技术鉴定。认为此方法是一种新的方法,理论正确,方法先进合理;对保证铁水质量,降低成本行之有效;能起指导生产的作用。配料对冲天炉来说是保证铁水化学成分与性能的唯一手段。目前冲天炉配料计算有分析法,图解法和选举法。它们能够满足铁水成分要求,已被无数生产实践所证实。随着工业的发展,对铸铁不仅要求提高质量,而且要不断的降低成本。特别是扩大企业自主权以后,实行三级经济核算,进行利润提成。降低成本就显得更加重要。哈尔滨科技大学从79年6月开始研究配料最优化问题。从理论上提出了用电子计算机实现冲天炉最低成本配料法,被选为全国第一次铸铁及其熔炼学组宣读论文。79年10月哈科大与哈锅炉厂合作。对HT15—33进行试验。通过48炉次,熔炼151吨铁水的生产试验。性能、成分合格,可降低成本11.41%每吨下降14.71... 用电子计算机实现最优化配料,是在保证铁水化学成分与性能的情况下使金属炉料的成本最低。文中介绍了此方法的数学模型。电子计算机程序,配料在生产中使用情况和经济效果分析。哈尔滨锅炉厂在HT15—33上使用,可降低成本11.41%。哈尔滨市科学技术委员会1980年7月14日对《用电子计算机实现冲天炉最低成本配料新方法》进行了技术鉴定。认为此方法是一种新的方法,理论正确,方法先进合理;对保证铁水质量,降低成本行之有效;能起指导生产的作用。配料对冲天炉来说是保证铁水化学成分与性能的唯一手段。目前冲天炉配料计算有分析法,图解法和选举法。它们能够满足铁水成分要求,已被无数生产实践所证实。随着工业的发展,对铸铁不仅要求提高质量,而且要不断的降低成本。特别是扩大企业自主权以后,实行三级经济核算,进行利润提成。降低成本就显得更加重要。哈尔滨科技大学从79年6月开始研究配料最优化问题。从理论上提出了用电子计算机实现冲天炉最低成本配料法,被选为全国第一次铸铁及其熔炼学组宣读论文。79年10月哈科大与哈锅炉厂合作。对HT15—33进行试验。通过48炉次,熔炼151吨铁水的生产试验。性能、成分合格,可降低成本11.41%每吨下降14.71元。据有关资料介绍我国每年铸铁件产量为300—400万吨左右,如果都采用此方法配料。每年可节约4000—5000多万元。 A nuclear power system is very vast and complex. Whole national nuclear power may consist of several types of reactors. These types of reactors make up a symbiotic fuel cycle system. The technology of thermal converters hasmatured and its power generation cost is cheaper. But its uranium utilization is lower. Although the gain of nuclear fuel for FBR is very fast, more inventory of fissible fuel and higher capital cost are needed, and the inventory during initial stage of FBR development must be supplied by... A nuclear power system is very vast and complex. Whole national nuclear power may consist of several types of reactors. These types of reactors make up a symbiotic fuel cycle system. The technology of thermal converters hasmatured and its power generation cost is cheaper. But its uranium utilization is lower. Although the gain of nuclear fuel for FBR is very fast, more inventory of fissible fuel and higher capital cost are needed, and the inventory during initial stage of FBR development must be supplied by the thermal converters. So there exists an optimal mix of thermal converters and FBR, which can achieve better economic effect in this system. Besides, the economic scale of nuclear industry enterprises is all very large now. It is necessary to consider the appropriate introduction schedule of these enterprises.This paper describes the dynamic linear programming model developed for a nuclear power system. Based on the physical essence of each process in this system and nuclear fuel flows, the various equilibrium equations and restraint relationships of variables are set up. These mathematics models describ the wbnle physical process of nuclear fuel cycle. Both linear programming and mixed integer programming are used to solve these problems. The primary results have welt represented the dynamic characteristic of whole system and given out the activity level of each process. the flow rate of nuclear fuel between processes and the number of ecomomie scale enterprises in each time period under optimization condition. The dynamic linear programming model is an efficient approach for project of the nuclear power system. 核动力系統是一个非常庞大和复杂的系統,一个国家的核动力系統可能由几种堆型所組成,这些堆型結合在一起就构成了一个組合的燃料循环体系。热中子轉化堆技术成熟,发电成本經济,但对核燃料的利用率低。快中子增殖堆核燃料的增产速度很高,但初装的可裂变材料多,基建投資大,其初始发展阶段所需燃料向須由热中子轉化堆提供。因此,在这种組合体系內必然存在着能达到較好經济效果的热中子堆和快中子堆最优配置方式。此外,核工业企业的經济規模都很大,需考虑它們最优引入的时間日程表。本文对核动力系統建立了动态綫性規划模型。針对核动力系統各个工艺环节的物理实質及核燃料的流程,建立了各种平衡方程式及各变量間的約束关系式,从而用数学模型描述整个核燃料循环的物理过程,并用綫性規划和混合整数規划方法求解。初步計算結果較好地反映了系統的动态特性,給出了在最优化条件下每个时間周期各个工艺环节的活动水平、环节間的物料流量以及各个工艺环节經济規模企业的个数等数据。这种动态綫性規划模型对研究核动力系統发展規划問題是一种有效的手段。
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