The paper discusses how the inventory control of army equipment material runs sytematically under the two-level maintenance system,and establishes the inventory control model based on system dynamics.On the basis of m...The paper discusses how the inventory control of army equipment material runs sytematically under the two-level maintenance system,and establishes the inventory control model based on system dynamics.On the basis of modeling and simulation,the influence of different inventory upper limit on the whole system is studied,and the optimal inventory control mechanism under the model condition is foud.In addition,through the simulation of two replenishment strategies(s,S) and(T,s,S),the advantages and disadvantages and feasibility of each replenishment strategy are analyzed.展开更多
Traffic management in underground mines,especially on production ramps,is a difficult problem to optimize and control.Most operations use one of a few common policies;e.g.,the so-called ‘‘lock-out" and‘‘loade...Traffic management in underground mines,especially on production ramps,is a difficult problem to optimize and control.Most operations use one of a few common policies;e.g.,the so-called ‘‘lock-out" and‘‘loaded-vehicle-priority" policies.The work presented in this paper uses discrete-event simulation to study the efficiency of multiple policies.Based on simulation results,an improvement to the common lock-out policy is proposed.This new policy utilizes the rules of the lock-out policy but integrates an option that allows a group of vehicles to be given temporary priority in a certain direction of travel.Quantitative results are provided and,based on these,a systematic technique for ramp design that aims to optimize the efficiency of underground mine ramp traffic flow is described.展开更多
This paper introduces the basic viewpoints and characteristics of Bayesian statistics. Which provides a theoretical basis for solving the problem of small sample of flight simulator using Bayesian method. A series of ...This paper introduces the basic viewpoints and characteristics of Bayesian statistics. Which provides a theoretical basis for solving the problem of small sample of flight simulator using Bayesian method. A series of formulas were derived to establish the Bayesian reliability modeling and evaluation model for flight simulation equipment. The two key problems of Bayesian method were pointed out as follows： obtaining the prior distribution of WeibuU parameter, calculating the parameter a posterior distribution and parameter estimation without analytic solution, and proposing the corresponding solution scheme.展开更多
A coal slurry mixing tank is a key piece of equipment in the preparation of coal slurry for direct coal liquefaction.It is a gas-liquid-solid three-phase mixing device.Based on the performance of the existing coal slu...A coal slurry mixing tank is a key piece of equipment in the preparation of coal slurry for direct coal liquefaction.It is a gas-liquid-solid three-phase mixing device.Based on the performance of the existing coal slurry mixing equipment,a type of test equipment for horizontal continuous coal slurry preparation was developed,but to this point has limited research results.The test equipment consists of a mixing cylinder,mixer,stirring impeller and other components.Slurry mixing experiments were undertaken using the prototype,testing the performance of the device.A mathematical model was proposed specifically for the operation of a coal slurry mixing tank that is horizontally operated with high slurry concentration and rotary flow.The flow field in the horizontal coal mixing tank was simulated with the computational fluid dynamic (CFD) method.The experimental results match well with the CFD simulation results.Results show that the test device of a coal slurry mixing tank can be used to model the mixing of pulverized coal and the solvent oil.A strong correlation was obtained.展开更多
文摘The paper discusses how the inventory control of army equipment material runs sytematically under the two-level maintenance system,and establishes the inventory control model based on system dynamics.On the basis of modeling and simulation,the influence of different inventory upper limit on the whole system is studied,and the optimal inventory control mechanism under the model condition is foud.In addition,through the simulation of two replenishment strategies(s,S) and(T,s,S),the advantages and disadvantages and feasibility of each replenishment strategy are analyzed.
基金funded by the Natural Science and Engineering Research Council of Canada (NSERC) under project CRDPJ 44SBO4-12funding provided by Barrick Gold Corporation and Peck Tech Consulting Ltd
文摘Traffic management in underground mines,especially on production ramps,is a difficult problem to optimize and control.Most operations use one of a few common policies;e.g.,the so-called ‘‘lock-out" and‘‘loaded-vehicle-priority" policies.The work presented in this paper uses discrete-event simulation to study the efficiency of multiple policies.Based on simulation results,an improvement to the common lock-out policy is proposed.This new policy utilizes the rules of the lock-out policy but integrates an option that allows a group of vehicles to be given temporary priority in a certain direction of travel.Quantitative results are provided and,based on these,a systematic technique for ramp design that aims to optimize the efficiency of underground mine ramp traffic flow is described.
文摘This paper introduces the basic viewpoints and characteristics of Bayesian statistics. Which provides a theoretical basis for solving the problem of small sample of flight simulator using Bayesian method. A series of formulas were derived to establish the Bayesian reliability modeling and evaluation model for flight simulation equipment. The two key problems of Bayesian method were pointed out as follows： obtaining the prior distribution of WeibuU parameter, calculating the parameter a posterior distribution and parameter estimation without analytic solution, and proposing the corresponding solution scheme.
基金Project (No. 2008C21021) supported by the Science and Technology Research Program of Zhejiang Province, China
文摘A coal slurry mixing tank is a key piece of equipment in the preparation of coal slurry for direct coal liquefaction.It is a gas-liquid-solid three-phase mixing device.Based on the performance of the existing coal slurry mixing equipment,a type of test equipment for horizontal continuous coal slurry preparation was developed,but to this point has limited research results.The test equipment consists of a mixing cylinder,mixer,stirring impeller and other components.Slurry mixing experiments were undertaken using the prototype,testing the performance of the device.A mathematical model was proposed specifically for the operation of a coal slurry mixing tank that is horizontally operated with high slurry concentration and rotary flow.The flow field in the horizontal coal mixing tank was simulated with the computational fluid dynamic (CFD) method.The experimental results match well with the CFD simulation results.Results show that the test device of a coal slurry mixing tank can be used to model the mixing of pulverized coal and the solvent oil.A strong correlation was obtained.
