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In the study of Reliability Technology, failures reflect in the inability to perform of basic parts. In order to seek the fundamental causes, FMA (function-motion-action) function decomposition model was utilized. By the decomposition stepwise, all basic actions formed the complex mechanism functions were found out, which were called Action. The failure model of action units was built by the fuzzy control theory. The key actions were worked out and the improved design measures were put forward, which proves the method valid.

In the combustion process of pulverized coal injection into blast furnace, the chlorine goes into the unburned pulverized coal is about 17%, the chlorine in the unburned coal keeps original state; The chlorine goes into the blast furnace gas is about 83%, and these chlorine stay as Hcl gas. Changes in air temperature and oxygen rate had no significant effect on the decomposition of chlorine in coal, resulting the rate of Cl into the blast furnace gas is difficult to increase significantly.

The existence forms of chlorine entered into blast furnace are chloride created by Cl- and metal cation or organic speciation absorbed in specular coal or structure macromolecule of coal. The chlorine entered into blast furnace merges with blast furnace gas in the form of HCl after conducted a series of chemical reactions. With the increasing of HCl content in blast furnace gas, the coke reactivity decreases and the coke post reaction strength increases, and the reduction process of iron ore is restrained and the low temperature reduction degradation property increases. However, the corrosion of gas pipeline and TRT blade is aggravated by the HCl in blast furnace gas, and then blast furnace gas conveying process and normal operation of TRT unit are affected.

The relation between chlorine and combustion process of pulverized coal in tuyere zone is affected by the existence form of chorine in coal. The combustion process of pulverized coal in tuyere zone is restrained by chorine of coal when the existence form of chorine is chloride created by Cl- and metal cation. The combustion process of pulverized coal in tuyere zone is improved by chorine of coal if chorine existents with the form of combination of HCl and nitrogen functional groups of coal macromolecules. Under the combustion conditions of tuyere zone in blast furnace, the distribution ratio of chlorine in unburned pulverized coal and blast furnace gas is approximately 60% and 40%, respectively.

Groundwater remediation by nanoparticles has received increasing interest in recent years. This report presents a thorough evaluation of hexavalent chromium removal in aqueous solutions using iron (Feo) nanoparticles. Cr(VI) is a major pollutant of groundwater. Zero-valent iron, an important natural reductant of Cr(VI), is an option in the remediation of contaminated sites, transforming Cr(VI) to essentially nontoxic Cr(III). At a dose of 0.4 g/L, 100% off Cr(VI) (20 mg/L) was degraded. The Cr(VI) removal efficiency decreased significantly with increasing initial pH. Different Feotype was compared in the same conditions. The reactivity was in the order starch-stabilized Feonanoparticles>Feonanoparticles>Feopowder>Feofilings. Electrochemical analysis of the reaction process led to the conclusion that Cr(OH)3should be the final product of Cr(VI). Iron nanoparticles are good choice for the remediation of heavy metals in groundwater.

The characteristics of the railway marshalling yard and the particular conditions of our railway transportation are stated. It is pointed out that the utilization of the decentralized automatic rolling speed control system is an effective road to carry out rolling speed automation of our marshalling yard. It is proposed that in the rolling speed controlling, the utilization of mathematical statistical method to find out the variable regularities of the running resistance of the car (or cut) prior to and post-retarder and the utilization of “tabic look-up” to determine the exit speed at retarder are both simple and effective in controlling. Besides, effect in operation of the system is also introduced.

The problem of optimal control of a finite dam in the class of policies has been considered by Lam Yeh [6], [7]. In this paper, by using the first Dynkin formula, the same problems of specifying an optimal policy in the class of the policies to minimize the expected total discounted cost as well as the long-run average cost are considered. Both the expected total discounted cost and long-run average cost are determined explicitly, and then the optimal policy can be found numerically, Also, we obtain the transition density function and the resolvent operator of a reflecting Wiener process.