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The materials supply for sea islands is the basis for ensuring survival needs of persons on sea islands. Considering factors such as transportation cost，storage cost，recycling demand and transportation capacity, it is a vehicle path planning problem with time window and capacity limit to use many transportation tools to supply materials for sea islands within a time cycle. The intelligent algorithm provides a preferable solution to solve this complex irregular optimization problem. The paper establishes a mathematical model of mission planning of materials supply for sea islands, explores the solving process of genetic algorithm， and uses an example to calculate it. The optimization result shows that the scheme can save transportation costs and storage costs， and also meet the need of materials supply cycle，which can provide a reference for scientific mission planning of materials supply for sea islands. [ABSTRACT FROM AUTHOR]

The observation data procession of target about traditional naval gun is based on installation site, dues to factors such as swing and deformation datum change will cause observation data error and affect firing accuracy, this paper analyzes the naval gun firing accutacy caused by the state of platform and naval gun enchmark assumptions, new methods of data processing is put forward, the mathematical model for calculating the arameters of observation target is established, which provides a new way to process the observation data. [ABSTRACT FROM AUTHOR]

In order to solve the problems of high energy consumption and high reabsorption, microwave dehydration technology of lignite was applied in this paper. The lignite with four different particle sizes from eastern Inner JVIongolia was treated by a self-developed microwave system under five different powers. The mathematical model for the moisture changes of lignite was developed and the relevant results were determined by finite difference method. And the computational results were in good agreement with the experimental results. The scanning electron microscope( SEIVI ) and low temperature nitrogen absorption method were applied to study the surface features and porous structure of coal samples. Distribution of oxygen-functional groups of carboxyl and phenol-hydroxyl was evaluated based on the chemical analysis results. Readsorption experiment in constant temperature and humidity with thermogravimetric analysis were performed to study the characteristics of readsorption and spontaneous combustion. It was found that the moisture after the readsorption of the lignite dried by microwave was far lower than 19. 87%, the moisture after the readsorption of the lignite dried by hot air, and the ignition temperature were increased to more than 295 °C from 275 °t. The results indicated that the interfacial stability of lignite is improved by microwave, and the dehydrated lignite is difficult to re-absorb water and combust spontaneously after microwave during. [ABSTRACT FROM AUTHOR]

A mathematical model of thermal reversal oxidation of the low concentration methane was established in this paper. The computational fluid dynamics method was used to simulate the temperature distribution and methane concentration distribution under various operating parameters. The calculated values of methane conversion showed good agreement with the corresponding available experimental data. The model was used to investigate the effects of operational conditions such as the approach velocity and equivalence ratio on the oxidation of methane. The results show that the temperature distribution within the bed is substantially M-typed;the high temperature zone and the methane concentration distribution curve along the direction of gas flow move periodically; the greater the inlet methane concentration, the higher the temperature peak, the closer to the inlet end of the temperature curve and the wider the high-temperature region; if the premixed methane gas flow rate increases from 0. 15 m/s to 0. 70 m/s,the maximum temperature peak and the high temperature zone change little, because as the gas flow velocity increases, both the heat releasing in the reaction bed and the heat carried out by the flow increase. [ABSTRACT FROM AUTHOR]

In order to rationally perform the slope stability analysis, a fast procedure to determine the critical reliability slip surface (with the minimum reliability index) was proposed in this paper. The steps are as follows; a large number of potential slip surfaces are randomly generated and the correlation coefficients between the safety factors of potential slip surfaces and the deterministic critical slip surface are calculated. Based on the calculated coefficients, the slip surfaces whose correlation coefficients fall within a prescribed interval are categorized into one slip surface group. The 'pseudo' reliability indices of slip surfaces within one slip surface group are then calculated by fast Monte-Carlo method with only two samplings. The slip surface with the minimum 'pseudo' reliability index is regarded as the representative slip surface of the group. The critical reliability slip surface can be obtained by comparing those representative slip surfaces from all the slip surface groups. The case studies have shown that the fast Monte-Carlo method is applicable to soil slope reliability analysis. [ABSTRACT FROM AUTHOR]

In order to study the law of gas desorption and emission, a desorption experiment of coal particles in different sizes under different initial pressures was designed. And the measured curves of gas desorption accumulated amount with the change of time were obtained. According to Darcy law, the paper also built the mathematical model of gas emission which was disposed with finite difference method. The visual Basic language was used to solve and calculate the mathematical model. The variation regulation of gas pressure in the inter coal particle and the accumulative desorption quantity at different pressure are finally obtained. Through comparing the simulation results and experiment results, the conclusion shows that the gas emission from the coal particles corresponds to Darcy law. [ABSTRACT FROM AUTHOR]