This paper presents a combination of experimental and numerical investigations on the dynamic response of scaling cabin structures under internal blast loading.The purpose of this study is to modify the similar relati...This paper presents a combination of experimental and numerical investigations on the dynamic response of scaling cabin structures under internal blast loading.The purpose of this study is to modify the similar relationship between the scaled-down model and the prototype of the cabin structures under internal blast loading.According to the Hopkinson’s scaling law,three sets of cabin structure models with different scaling factors combined with different explosive masses were designed for the experimental study.The dynamic deformation process of the models was recorded by a three-dimensional digital imaging correlation(DIC)method and a 3D scanning technology was used to reconstruct the deformation modes of the specimen.In addition,a finite element model was developed for the modification of the scaling law.The experimental results showed that the final deflection-to-thickness ratio was increased with the increase of the model size despite of the similar trend of their deformation processes.The reason for this inconsistency was discussed based on the traditional scaling law and a modified formula considering of the effects of size and strain-rate was provided.展开更多
For rigid-flexible coupling multi-body with variable topology,such as the system of internally carried air-launched or heavy cargo airdrop,in order to construct a dynamic model with unified form,avoid redundancy in th...For rigid-flexible coupling multi-body with variable topology,such as the system of internally carried air-launched or heavy cargo airdrop,in order to construct a dynamic model with unified form,avoid redundancy in the modeling process and make the solution independent,a method based on the equivalent rigidization model was proposed.It divides a system into independent subsystems by cutting off the joints,of which types are changed with the operation process of the system.And models of different subsystems can be constructed via selecting suitable modeling methods.Subsystem models with flexible bodies are on the basis of the equivalent rigidization model which replaces the flexible bodies with the virtual rigid bodies.And the solution for sanction,which is based on the constraints force algorithm(CFA)and vector mechanics,can be independent on the state equations.The internally carried air-launched system was taken as an example for verifying validity and feasibility of the method and theory.The dynamic model of aircraft-rocket-parachute system in the entire phase was constructed.Comparing the modeling method with the others,the modeling process was programmed;and form of the model is unified and simple.The model,method and theory can be used to analyze other similar systems such as heavy cargo airdrop system and capsule parachute recovery system.展开更多
A novel reconfigurable hardware system which uses both muhi-DSP and FPGA to attain high performance and real-time image processing are presented. The system structure and working principle of mainly processing multi-B...A novel reconfigurable hardware system which uses both muhi-DSP and FPGA to attain high performance and real-time image processing are presented. The system structure and working principle of mainly processing multi-BSP board, extended multi-DSP board are analysed. The outstanding advantage is that the communication among different board components of this system is supported by high speed link ports ＆ serial ports for increasing the system performance and computational power. Then the implementation of embedded real-time operating systems （RTOS） by us is discussed in detail. In this system, we adopt two kinds of parallel structures controlled by RTOS for parallel processing of algorithms. The experimental results show that exploitive period of the system is short, and maintenance convenient. Thus it is suitable for real-time image processing and can get satisfactory effect of image recognition.展开更多
自联合国国际搜索与救援咨询团(The International Search and Rescue Advisory Group,简称INSARAG)成立30多年来,通过不断总结巨灾国际救援经验,形成了一套覆盖国际救援准备阶段、行动阶段到撤离阶段的国际救援全流程全要素的协调工作...自联合国国际搜索与救援咨询团(The International Search and Rescue Advisory Group,简称INSARAG)成立30多年来,通过不断总结巨灾国际救援经验,形成了一套覆盖国际救援准备阶段、行动阶段到撤离阶段的国际救援全流程全要素的协调工作机制,并通过出台一系列的指南、指导性文件和推荐性技术文件,规范救援能力和队伍建设,强化国际救援协调和现场救援的效率。该文系统介绍了INSARAG标准和技术文件组成体系架构,并阐述了各标准及技术文件的出台背景、主要内容及对中国的搜救队伍建设的推动作用,并讨论其对我国灾害救援工作的启示与借鉴意义。展开更多
基金the support from the National Natural Science Foundation of China under Grant No. 11902031,No. 11802030 , No. 11802031Beijing Municipal Science and Technology Project Management Approach under No. Z181100004118002
文摘This paper presents a combination of experimental and numerical investigations on the dynamic response of scaling cabin structures under internal blast loading.The purpose of this study is to modify the similar relationship between the scaled-down model and the prototype of the cabin structures under internal blast loading.According to the Hopkinson’s scaling law,three sets of cabin structure models with different scaling factors combined with different explosive masses were designed for the experimental study.The dynamic deformation process of the models was recorded by a three-dimensional digital imaging correlation(DIC)method and a 3D scanning technology was used to reconstruct the deformation modes of the specimen.In addition,a finite element model was developed for the modification of the scaling law.The experimental results showed that the final deflection-to-thickness ratio was increased with the increase of the model size despite of the similar trend of their deformation processes.The reason for this inconsistency was discussed based on the traditional scaling law and a modified formula considering of the effects of size and strain-rate was provided.
文摘For rigid-flexible coupling multi-body with variable topology,such as the system of internally carried air-launched or heavy cargo airdrop,in order to construct a dynamic model with unified form,avoid redundancy in the modeling process and make the solution independent,a method based on the equivalent rigidization model was proposed.It divides a system into independent subsystems by cutting off the joints,of which types are changed with the operation process of the system.And models of different subsystems can be constructed via selecting suitable modeling methods.Subsystem models with flexible bodies are on the basis of the equivalent rigidization model which replaces the flexible bodies with the virtual rigid bodies.And the solution for sanction,which is based on the constraints force algorithm(CFA)and vector mechanics,can be independent on the state equations.The internally carried air-launched system was taken as an example for verifying validity and feasibility of the method and theory.The dynamic model of aircraft-rocket-parachute system in the entire phase was constructed.Comparing the modeling method with the others,the modeling process was programmed;and form of the model is unified and simple.The model,method and theory can be used to analyze other similar systems such as heavy cargo airdrop system and capsule parachute recovery system.
基金This project was supported by the National Natural Science Foundation of China(60135020) National Key Pre-researchProject of China(413010701 -3) .
文摘A novel reconfigurable hardware system which uses both muhi-DSP and FPGA to attain high performance and real-time image processing are presented. The system structure and working principle of mainly processing multi-BSP board, extended multi-DSP board are analysed. The outstanding advantage is that the communication among different board components of this system is supported by high speed link ports ＆ serial ports for increasing the system performance and computational power. Then the implementation of embedded real-time operating systems （RTOS） by us is discussed in detail. In this system, we adopt two kinds of parallel structures controlled by RTOS for parallel processing of algorithms. The experimental results show that exploitive period of the system is short, and maintenance convenient. Thus it is suitable for real-time image processing and can get satisfactory effect of image recognition.
文摘自联合国国际搜索与救援咨询团(The International Search and Rescue Advisory Group,简称INSARAG)成立30多年来,通过不断总结巨灾国际救援经验,形成了一套覆盖国际救援准备阶段、行动阶段到撤离阶段的国际救援全流程全要素的协调工作机制,并通过出台一系列的指南、指导性文件和推荐性技术文件,规范救援能力和队伍建设,强化国际救援协调和现场救援的效率。该文系统介绍了INSARAG标准和技术文件组成体系架构,并阐述了各标准及技术文件的出台背景、主要内容及对中国的搜救队伍建设的推动作用,并讨论其对我国灾害救援工作的启示与借鉴意义。
