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31.
本文对白云鄂博主矿采场铁公路联合运输向公路运输转换位置是否确定为1638m水平以及运输工艺转换过程中相关问题进行分析论证,提出主矿采场铁路至少可向下延深一个水平,技术上可行,节约运费千万元以上。 相似文献
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A new approach to study ergodicity of filtering processes is presented. It is based on the vanishing discount approach to discounted functional of filtering process. We show that limit superior of the Cesaro averages of the functionals is the same for all initial conditions from which the uniqueness of invariant measures of filtering processes follows. The approach is based on certain assumption for which we provide a sufficient condition using concavity arguments. In addition we show the existence of solutions to the Poisson equation corresponding to filtering process with concave functional. The assumptions are then extended to the controlled case and using similar concave arguments we obtain the existence of solutions to the Bellman equation corresponding to partially observed average cost per unit time problem. 相似文献
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In this paper we present the results of a simulation study to explore the ability of Bayesian parametric and nonparametric models to provide an adequate fit to count data of the type that would routinely be analyzed parametrically either through fixed-effects or random-effects Poisson models. The context of the study is a randomized controlled trial with two groups (treatment and control). Our nonparametric approach uses several modeling formulations based on Dirichlet process priors. We find that the nonparametric models are able to flexibly adapt to the data, to offer rich posterior inference, and to provide, in a variety of settings, more accurate predictive inference than parametric models. 相似文献
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Jantana Tangaromsuk Abhijeet P. Borole Maleeya Kruatrachue Prayad Pokethitiyook 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(10):1375-1380
BACKGROUND: A single‐stage reactor, in which the growth of bacterial culture, induction of desulfurizing enzymes, and desulfurization reaction are carried out in a single step, was adopted to investigate desulfurization of dibenzothiophene (DBT) at high cell densities. Rhodococcus erythropolis, IGTS8 was used as the biocatalyst. Optimal conditions for bacterial growth and DBT desulfurization were investigated. RESULTS: Optimization of fermentation conditions was necessary to obtain high cell densities including controlling accumulation of acetate. Under optimal operating conditions, the maximum optical density at 600 nm (OD600) was measured to be 26.6 at 118 h of cultivation. When biodesulfurization of DBT in model oil with a high cell density culture of IGTS8 was investigated, accumulation of sulfate was found to limit the extent of desulfurization. A sulfate removal step was added to obtain a single‐stage integrated biodesulfurization process. Sulfate removal was achieved via an aqueous bleed stream and use of a separation unit to recycle the organic phase. CONCLUSION: A proof of principle of a complete system capable of biocatalyst growth, induction, desulfurization and by‐product separation was demonstrated. This system enables simplification of the biodesulfurization process and has potential to lower the operating cost of the bioprocess. Copyright © 2008 Society of Chemical Industry 相似文献
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根据我国专利法的原则,在对我国催化重整和芳烃生产专利检索过程和结果进行分析的基础上,阐述了对目前我国催化重整工艺专利市场的几点看法并提出对策。 相似文献
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本文研究了浸胶工艺对Nomex蜂窝性能的影响,分析探讨了提高Nomex蜂窝性能及外观质量的途径。研究结果表明:采取新的浸胶工艺制作的Nomex蜂窝,各项性能全面达到法国宇航材料标准。 相似文献
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The infrastructure renewal program at MIT consists of a large number of projects with an estimated budget that could approach $1 billion. Infrastructure renewal at the Massachusetts Institute of Technology (MIT) is the process of evaluating and investing in the maintenance of facility systems and basic structure to preserve existing campus buildings. The selection and prioritization of projects must be addressed with a systematic method for the optimal allocation of funds and other resources. This paper presents a case study of a prioritization method utilizing multi-attribute utility theory. This method was developed at MIT's Department of Nuclear Engineering and was deployed by the Department of Facilities after appropriate modifications were implemented to address the idiosyncrasies of infrastructure renewal projects and the competing criteria and constraints that influence the judgment of the decision-makers. Such criteria include minimization of risk, optimization of economic impact, and coordination with academic policies, programs, and operations of the Institute. A brief overview of the method is presented, as well as the results of its application to the prioritization of infrastructure renewal projects. Results of workshops held at MIT with the participation of stakeholders demonstrate the feasibility of the prioritization method and the usefulness of this approach. 相似文献