Static and dynamic design based on hierarchical optimization for materials and structure of porous metals

A static and dynamic collaborative optimization method for materials and structure with uniform periodic microstructure is presented.The sensitivity formulae of hierarchical optimization,i.e.,material design,structure design and integrated design for porous metals,are given.On the base of the hierarchical optimization model,numerical experiments of an MBB beam and a cantilever one were carried out.Based on porous metals bearing multi-functionality,the differences and applicability of hierarchical optimization are discussed in the structure loading field.It is concluded that structure design is mainly oriented to structure efficiency,material design is mainly oriented to multi-functionality,and integrated design is oriented to structure efficiency and multi-functionality.This work provides some useful ideas for the selection of porous metals design method.

The personal protective equipment(PPE)based on individual combat:A systematic review and trend analysis

With the development of ordnance technology,the survival and safety of individual combatants in hightech warfare are under serious threat,and the Personal Protective Equipment(PPE),as an important guarantee to reduce casualties and maintain military combat effectiveness,is widely developed.This paper systematically reviewed various PPE based on individual combat through literature research and comprehensive discussion,and introduced in detail the latest application progress of PPE in terms of material and technology from three aspects:individual integrated protection system,traditional protection equipment,and intelligent protection equipment,respectively,and discussed in depth the functional improvement and optimization status brought by advanced technology for PPE,focusing on the achievements of individual equipment technology application.Finally,the problems and technical bottlenecks in the development of PPE were analyzed and summarized,and the development trend of PPE were pointed out.The results of the review will provide a forward-looking reference for the current development of individual PPE,and are important guidance for the design and technological innovation of advanced equipment based on the future technological battlefield.

A systematic review of steel bridge deck pavement in China

As an important part of steel bridge deck,the engineering quality and service condition of steel bridge deck pavement(SBDP)directly affects the capacity and operational efficiency of the bridge.This paper reviews the history of the development of SBDP in China over the past 20 years from the exploration stage,rapid development stage and prosperity stage.The development and application of SBDP at different stages are discussed in terms of materials,structure,design,performance evaluation,maintenance and rehabilitation,respectively.The advantages and disadvantages of different pavement materials and structures,and the application of different research methods are summarized.The review shows that the improvement of pavement materials and structures and the development of new materials should be further studied on the multi-scale to enhance the durability of pavement materials,so as to extend the service life of pavements.The design method of SBDP related to the synergistic effect of vehicle,pavement and bridge should be established,and the design concept and method standard of rigid base pavement structure should be improved and formulate a complete design standard.In addition,multi-disease intelligent identification system and equipment should be studied to track the entire course of disease development in real time.And it is necessary to develop appropriate algorithms to select and classify the complex data of disease and maintenance history.