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
Yam hairiness is a complex concept, which generally cannot be completely defined by a single figure. Hairiness can be considered as the fiber ends and loops standing out from the main compact yarn body. Uster hairines...Yam hairiness is a complex concept, which generally cannot be completely defined by a single figure. Hairiness can be considered as the fiber ends and loops standing out from the main compact yarn body. Uster hairiness system characterizes the hairiness by H value, i.e. the mean value of the total length of all hairs within one centimeter of yarn. The raw data HI are in fact realization of spatial process (hairiness spatial process -- HSP) and can be used for more complex evaluation of hairiness characteristics in the space and frequency domain. The main aim of this contribution is description of some tools for spatial characterization of yarn hairiness. The simple methods for complex characterization of lISP statistical behavior (stationarity, independence, linearity etc. ) are presented. The techniques based on the embedding dimension and correlation integral or long-range dependences evaluation are discussed. The selected methods are core of HYARN program in MATLAB. Application of this program for deeper characterization of artificial data and cotton type yam are shown.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Supported by the research project"Textile center"of Czech Ministry of Education1M4674788501
文摘Yam hairiness is a complex concept, which generally cannot be completely defined by a single figure. Hairiness can be considered as the fiber ends and loops standing out from the main compact yarn body. Uster hairiness system characterizes the hairiness by H value, i.e. the mean value of the total length of all hairs within one centimeter of yarn. The raw data HI are in fact realization of spatial process (hairiness spatial process -- HSP) and can be used for more complex evaluation of hairiness characteristics in the space and frequency domain. The main aim of this contribution is description of some tools for spatial characterization of yarn hairiness. The simple methods for complex characterization of lISP statistical behavior (stationarity, independence, linearity etc. ) are presented. The techniques based on the embedding dimension and correlation integral or long-range dependences evaluation are discussed. The selected methods are core of HYARN program in MATLAB. Application of this program for deeper characterization of artificial data and cotton type yam are shown.