This paper reports the evolution of textile structure and mechanical properties of vascular prosthesis in the level of the whole prosthesis and the constituent filaments with respect to the manufacturing process. The ...This paper reports the evolution of textile structure and mechanical properties of vascular prosthesis in the level of the whole prosthesis and the constituent filaments with respect to the manufacturing process. The tubular wall of the prosthesis is divided circumferentially into three zones; basic line (BL), remeshing line ( RL) and guide line ( GL). Some heterogeneity has been observed on the tubular wall in terms of stitch structure of the prosthesis and linear density of the constituent filaments. The breaking position of the prosthesis under circumferential tensile localizes preferentially in remeshing line that is the weakest zone by warp knitting with double needle bed. Furthermore, the statistical differences of the mechanical properties of the filaments of zone RL, GL and BL have been confirmed too. It is predictable that the deterioration of prosthesis, under physiological loads (periodical pulse blood pressure etc.), could happen firstly in the weaker zone in vivo.展开更多
Unquestionably,aircraft industry plays an important part in both economy and security of a nation.However,few of articles have dealt with the spatial development of this industry sector.The purpose of this article is ...Unquestionably,aircraft industry plays an important part in both economy and security of a nation.However,few of articles have dealt with the spatial development of this industry sector.The purpose of this article is to analyze the dynamics of agglomeration and diffusion of aircraft industry.In a historical view,with some spatial analysis methods,this research discusses the characteristics and patterns of aircraft industry's spatial organization and evolution,globally,nationally and regionally respectively.We find out there is a ‘Matthew effect' in aircraft industry of the world,and the spatial evolution of the industry is consistent with the nation's industrialization process.Then,it concludes that the main agglomeration forces consist of capital,talents,technology and cluster's advantages,and the main diffusion forces include comparative advantages,cost and risk sharing,emerging markets,development policy for backward regions and military requirements.All the factors can be divided into market forces making the spatial development of aircraft industry normal and non-market forces making that irregular.In particular,lessons from the USA and France are expected to be conducive to the rise of China's aircraft industry in the future.展开更多
Terms of sustainable and sustainability have been employed in various sectors and fields since around 1990. To make a society sustainable needs to find ways of having sustainable local activities. The ways may be to f...Terms of sustainable and sustainability have been employed in various sectors and fields since around 1990. To make a society sustainable needs to find ways of having sustainable local activities. The ways may be to find and revitalize local resources, or to support new life styles by accepting outsider's new ideas. I see those ways often taken from a perspective that the ways require a structure or institutional organization. To explore in-between ways, it would be better to have an alternative perspective and useful to learn from Southeast Asian cases of managing diversity while accepting new ways (cf. Reid, 2015). In this essay, I focus on a sustainable craft making of a men's hat kopiah meuketob in Aceh, Sumatra, which is traditional item for marriage but has been used in various imaginative ways and has been shaping a regional "craft-scape." I examine such ways and various facets of making the hat and conclude that a lesson from the case for making things sustainable is equal and flexible ways of participating in production processes.展开更多
基金Funded by the Shanghai Post Doctoral Foundation Overseas Returned Scholars' Foundation of Education Ministry the Shanghai Key Discipline Project
文摘This paper reports the evolution of textile structure and mechanical properties of vascular prosthesis in the level of the whole prosthesis and the constituent filaments with respect to the manufacturing process. The tubular wall of the prosthesis is divided circumferentially into three zones; basic line (BL), remeshing line ( RL) and guide line ( GL). Some heterogeneity has been observed on the tubular wall in terms of stitch structure of the prosthesis and linear density of the constituent filaments. The breaking position of the prosthesis under circumferential tensile localizes preferentially in remeshing line that is the weakest zone by warp knitting with double needle bed. Furthermore, the statistical differences of the mechanical properties of the filaments of zone RL, GL and BL have been confirmed too. It is predictable that the deterioration of prosthesis, under physiological loads (periodical pulse blood pressure etc.), could happen firstly in the weaker zone in vivo.
基金The National Natural Science Foundation of China (Grant no.40635026)
文摘Unquestionably,aircraft industry plays an important part in both economy and security of a nation.However,few of articles have dealt with the spatial development of this industry sector.The purpose of this article is to analyze the dynamics of agglomeration and diffusion of aircraft industry.In a historical view,with some spatial analysis methods,this research discusses the characteristics and patterns of aircraft industry's spatial organization and evolution,globally,nationally and regionally respectively.We find out there is a ‘Matthew effect' in aircraft industry of the world,and the spatial evolution of the industry is consistent with the nation's industrialization process.Then,it concludes that the main agglomeration forces consist of capital,talents,technology and cluster's advantages,and the main diffusion forces include comparative advantages,cost and risk sharing,emerging markets,development policy for backward regions and military requirements.All the factors can be divided into market forces making the spatial development of aircraft industry normal and non-market forces making that irregular.In particular,lessons from the USA and France are expected to be conducive to the rise of China's aircraft industry in the future.
文摘Terms of sustainable and sustainability have been employed in various sectors and fields since around 1990. To make a society sustainable needs to find ways of having sustainable local activities. The ways may be to find and revitalize local resources, or to support new life styles by accepting outsider's new ideas. I see those ways often taken from a perspective that the ways require a structure or institutional organization. To explore in-between ways, it would be better to have an alternative perspective and useful to learn from Southeast Asian cases of managing diversity while accepting new ways (cf. Reid, 2015). In this essay, I focus on a sustainable craft making of a men's hat kopiah meuketob in Aceh, Sumatra, which is traditional item for marriage but has been used in various imaginative ways and has been shaping a regional "craft-scape." I examine such ways and various facets of making the hat and conclude that a lesson from the case for making things sustainable is equal and flexible ways of participating in production processes.