Two-way concrete slabs are widely used around the world for the construction of many types of infrastructures and common buildings. The optimal sensor placement(OSP) in slabs with various opening positions is the most...Two-way concrete slabs are widely used around the world for the construction of many types of infrastructures and common buildings. The optimal sensor placement(OSP) in slabs with various opening positions is the most important issue in structural health monitoring(SHM) to increase reliability. In this study, a novel approach of OSP was evaluated to obtain the number and placement of sensors using examination of the closed loop performance. The nonlinear finite element(NFE) was used to discretize the mechanism behavior of slab. Multi-Objective Optimization based on the coordinate modal assurance criterion(COMAC) and cost considerations was considered in the optimization processes. All of the analysis, discretization and optimization process was designed and developed as a novel approach in Matlab by the author under the name ‘FEMS-COMAC’(FEM analysis of slab with COMAC). The points in the finite element method(FEM) mesh were classified as line by line information along the slab. The OSP in each line was optimized according to the objective function. The slabs with various width, thickness, aspect ratio and opening position were selected as case studies. The results of the OSP using the COMAC algorithm around the slab openings were compared with the novel ‘FEMS-COMAC’ method. The statistical analysis according Mann-Whitney criteria shows that there were significant differences between them in some of the case studies(mean P-value=0.54).展开更多
As in many American classics,the road is a central image in Jack Kerouac’s On the Road(1957)and Comac McCarthy’s The Road(2006).This paper intends to carry out a comparative analysis of this image in these two postm...As in many American classics,the road is a central image in Jack Kerouac’s On the Road(1957)and Comac McCarthy’s The Road(2006).This paper intends to carry out a comparative analysis of this image in these two postmodern masterpieces.The paper starts with an investigation of the image in the two works separately and ends with a more comprehensive and comparative study of this topic.展开更多
On the afternoon of July 16th,2018,at the Farnborough International Air Show,Cheng Rence,Chairman of Nanshan Aluminum,led a team to visit the booth of COMAC to deeply discuss about the raw materials purchase and prima...On the afternoon of July 16th,2018,at the Farnborough International Air Show,Cheng Rence,Chairman of Nanshan Aluminum,led a team to visit the booth of COMAC to deeply discuss about the raw materials purchase and primary processing,in order to further deepen cooperation.Chairman Cheng presented the展开更多
This paper systematically summarizes the basic philosophy and principles of airworthiness that COMAC follows in the process of developing C919 large passenger aircraft.It carries out type certification along with the ...This paper systematically summarizes the basic philosophy and principles of airworthiness that COMAC follows in the process of developing C919 large passenger aircraft.It carries out type certification along with the aircraft development process,and plans and implements compliance activities for airplane design features.Targeting the airworthiness requirements,COMAC has also established an airworthiness management system,including design assurance system and continuing airworthiness system,to ensure that aircraft are designed in accordance with airworthiness requirements,to show compliance with airworthiness requirements and to continuously ensure the airworthiness of airplane by dealing with continuing airworthiness events in service.展开更多
文摘Two-way concrete slabs are widely used around the world for the construction of many types of infrastructures and common buildings. The optimal sensor placement(OSP) in slabs with various opening positions is the most important issue in structural health monitoring(SHM) to increase reliability. In this study, a novel approach of OSP was evaluated to obtain the number and placement of sensors using examination of the closed loop performance. The nonlinear finite element(NFE) was used to discretize the mechanism behavior of slab. Multi-Objective Optimization based on the coordinate modal assurance criterion(COMAC) and cost considerations was considered in the optimization processes. All of the analysis, discretization and optimization process was designed and developed as a novel approach in Matlab by the author under the name ‘FEMS-COMAC’(FEM analysis of slab with COMAC). The points in the finite element method(FEM) mesh were classified as line by line information along the slab. The OSP in each line was optimized according to the objective function. The slabs with various width, thickness, aspect ratio and opening position were selected as case studies. The results of the OSP using the COMAC algorithm around the slab openings were compared with the novel ‘FEMS-COMAC’ method. The statistical analysis according Mann-Whitney criteria shows that there were significant differences between them in some of the case studies(mean P-value=0.54).
文摘As in many American classics,the road is a central image in Jack Kerouac’s On the Road(1957)and Comac McCarthy’s The Road(2006).This paper intends to carry out a comparative analysis of this image in these two postmodern masterpieces.The paper starts with an investigation of the image in the two works separately and ends with a more comprehensive and comparative study of this topic.
文摘On the afternoon of July 16th,2018,at the Farnborough International Air Show,Cheng Rence,Chairman of Nanshan Aluminum,led a team to visit the booth of COMAC to deeply discuss about the raw materials purchase and primary processing,in order to further deepen cooperation.Chairman Cheng presented the
文摘This paper systematically summarizes the basic philosophy and principles of airworthiness that COMAC follows in the process of developing C919 large passenger aircraft.It carries out type certification along with the aircraft development process,and plans and implements compliance activities for airplane design features.Targeting the airworthiness requirements,COMAC has also established an airworthiness management system,including design assurance system and continuing airworthiness system,to ensure that aircraft are designed in accordance with airworthiness requirements,to show compliance with airworthiness requirements and to continuously ensure the airworthiness of airplane by dealing with continuing airworthiness events in service.
