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891.
Based on the intelligent decision support system, a new method was presented to defense the catastrophic infectious disease such as SARS, Bird Flu, etc.. By using All Set theory, the decision support system (DSS) model can be built to analyze the noise information and forecast the trend of the catastrophe then to give the method or policy to defend the disease. The model system is composed of four subsystems: the noise analysis subsystem, forecast and simulation subsystem, diagnosis subsystem and second recovery subsystem. They are discussed briefly in this paper. This model can be used not only for SARS but also for other paroxysmal accidences.  相似文献   
892.
Anodic reaction mechanism of complicated antimony-lead concentrate in slurry electrolysis was investigated by the anodic polarization curves determined under various conditions. The main reactions on the anode are the oxidations of FeCln^(2-n) . Though the oxidation of jamesonite particle on the anode can occur during the whole process, it is less. With the help of mineralogy studies and relevant tests, the leaching reaction mechanism of jameson[to and gudmundite during slurry electrolysis was ascertained. Because of the oxidation reaction of FeCl3 produced by antimony-lead concentrate itself, the non-oxidation complex acid dissolution of jameson[re, the oxidation complex acid dissolution of gudmundite, and the oxidation of air carried by stirring, the leaching ratio of antimony reaches about 35% when HCl-NH4Cl solution is used to leach antimony-lead concentrate directly. So when the theoretical electric quantity is given to oxidation of antimony in slurry electrolysis, all of antimony, lead and iron containing in antimony-lead concentrate, are leached. The formation of sulfur is through the directly redox reaction of Fe^3 and jameson[re. The S^2- in jamesonite is oxidized into S^0 , and forms the crystals of sulfur again on the spot. The redox reaction of Fe^3 and H2S formed by non-oxidative acid dissolution of jamesonite is less.  相似文献   
893.
Based on the laws of momentum conservation and impulse in accelerating process, the distribution on speed of ununiform slurry flow in a horizontal pipe was studied. According to the momentum change of solid particles and conveying liquid of slurry flow during accelerating, and some effect factors, the relationship between the speed of solid particles and the speed of conveying liquid was obtained.When dealing with the friction between sliding solid particles and pipe, it is pivotal to reasonably distribute component of friction to each solid particle. The friction coefficient between solid particles was obtained by forces analysis and theoretic calculation, and can be used to calculate the friction force on every solid particle. The effect of friction on speed of ever), solid particle was investigated through the impulse law. The result is more accurate than that by using uniform friction on solid particles. It is completely new method to use above theory to get solid particles speed distribution, conveying liquid speed distribution and slurry speed distribution.  相似文献   
894.
In this article the research and development of X70 large diameter longitudinal seam submerged arc welded (LSAW) steel pipes for West-East Gas Transportation Pipeline project (WEGTP) in China are introduced, including the key technique, fabrication of pipe production line, mass production and the latest progress of LSAW steel pipe technique.  相似文献   
895.
Coverage layer coated in the internal wall of pipeline enables the friction drag to be reduced, the throughput and the gas transmission efficiency to be increased, the frequency of pigging and the number of the intermediate compressor station to be reduced, and the power consumption of the compressor to be decreased etc. The drag reduction is a high advanced scientific technique with outstanding economical benefit. The study and application of internal coating technique for drag reduction of 4000km trunk pipeline in West-East gas transmission pipeline (WEGTP) project are described, in which the main points are the drag reduction principle, coating process and the indoor study of this technique with own-decided knowledge property right at home.  相似文献   
896.
The all-position automatic welding machine system is the special welding system for pipeline girth automatic welding on site, which has been widely used in the long distance pipeline construction projects due to the advantages of automatic control for welding parameters at all position, moving speed of bugs and operating. This automatic pipeline welding system has been successfully used in several main pipeline projects in China, and has been approved by the constructors with the benefits of higher quality passing rate, higher welding efficiency and lower labor intensity.  相似文献   
897.
足球机器人比赛系统需要机器人团队的合作 .但RoboCup仿真组比赛所提供的通信系统模型是一个低带宽、不可靠通信系统 .为了更好的利用这有限的通信能力 ,提出了对应的解决通信问题的方法 .最后举例说明了若干个在团队合作中使用通信系统的应用 .  相似文献   
898.
研究了单指标数据序列的几种无量纲化变换及其性质,提出了一种对灰色斜率关联度的改进模型,改进后的关联度能够反映序列的正、负相关关系,并且对原始序列进行无量纲化变换处理时不影响关联系数及关联度的值,还研究了改进的关联度及关联系数的性质。该方法充分利用了序列各时点的信息及正、负相关性,所得关联分析结果较为客观可靠,并且易于在计算机上实现。  相似文献   
899.
定义了布尔函数的类差分和类差分平衡函数,研究了类差分平衡函数的密码学性质以及构造方法。作为类差分平衡函数的应用, 给出了Z24上逻辑函数是完全非线性函数的充要条件,并在首先分析得到所有四元类差分平衡函数的基础上,编程搜索出Z24上所有的完全非线性函数。  相似文献   
900.
提出了城市供水系统产权结构重组的两种基本模式,运用制度经济学和管理学理论,提出产权结构模式评价的指标与方法,分析了这两种产权结构模式的特性和在这两种模式下不同利益主体的行为与利益关系的变化特点及优缺点,并提出了缓解劣势的手段与方法。  相似文献   
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