Empirical observations suggest that many instructions and groups of instructions having the same inputs,and producing the same outputs. Such instructions do not have to be executed repeatedly-their result can be obtai...Empirical observations suggest that many instructions and groups of instructions having the same inputs,and producing the same outputs. Such instructions do not have to be executed repeatedly-their result can be obtained from records where they have been saved previously. This paper proposes an approach that uses compiler technique to exploit reuse for instruction group. In this approach ,the compiler first identifies code regions whose computation can be reused during dynamic execution. For each region,a library routing is invoked before the instruction in the region is executed. The function of the library routes is to record several instances of the region execution,including input register values and output register values. When it is found that a region has an instance that can be reused,then all the instructions in the region can be skipped and hence improve the performance.展开更多
Ice-going ships play a crucial role in polar transportation and resource extraction.Different from the existing modeling approach which assumes that ships remain stationary,dynamic overset grid technology and DFBI(Dyn...Ice-going ships play a crucial role in polar transportation and resource extraction.Different from the existing modeling approach which assumes that ships remain stationary,dynamic overset grid technology and DFBI(Dynamic Fluid-Body Interaction)method are employed in this paper to enable the free-running motion of the ship in modeling.A numerical model capable of simulating a ship navigating through pack ice area is proposed,which uses Computational Fluid Dynamics(CFD)method to solve the flow field and applies the Discrete Element Method(DEM)to simulate ship-ice and ice-ice interactions.Besides,the proposed high-precision method for generating pack ice area can be used in conjunction with the proposed numerical model.By comparing the numerical results with the available model test data and experimental observations,the effectiveness of the numerical model is validated,demonstrating its strong capability of predicting resistance and simulating ship navigation in pack ice,as well as its significant potential and applicability for further studies.展开更多
文摘Empirical observations suggest that many instructions and groups of instructions having the same inputs,and producing the same outputs. Such instructions do not have to be executed repeatedly-their result can be obtained from records where they have been saved previously. This paper proposes an approach that uses compiler technique to exploit reuse for instruction group. In this approach ,the compiler first identifies code regions whose computation can be reused during dynamic execution. For each region,a library routing is invoked before the instruction in the region is executed. The function of the library routes is to record several instances of the region execution,including input register values and output register values. When it is found that a region has an instance that can be reused,then all the instructions in the region can be skipped and hence improve the performance.
文摘Ice-going ships play a crucial role in polar transportation and resource extraction.Different from the existing modeling approach which assumes that ships remain stationary,dynamic overset grid technology and DFBI(Dynamic Fluid-Body Interaction)method are employed in this paper to enable the free-running motion of the ship in modeling.A numerical model capable of simulating a ship navigating through pack ice area is proposed,which uses Computational Fluid Dynamics(CFD)method to solve the flow field and applies the Discrete Element Method(DEM)to simulate ship-ice and ice-ice interactions.Besides,the proposed high-precision method for generating pack ice area can be used in conjunction with the proposed numerical model.By comparing the numerical results with the available model test data and experimental observations,the effectiveness of the numerical model is validated,demonstrating its strong capability of predicting resistance and simulating ship navigation in pack ice,as well as its significant potential and applicability for further studies.