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
Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to...Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to a cotton spinning sector and influence its quality.Those two properties can change the entire spinning process.Understanding this,moisture and temperature must be kept under control when used during the spinning process,once the environment is hot and dry,the cotton yarns absorb moisture and lose the minimal consistency.According to this information,this paper was developed testing four types of cotton yarns,one kind of cotton from Brazil and the others from Egypt.The yarns were exposed to different temperatures and moisture in five different tests and in each test,six samples were examined through physical and mechanical tests:resistance,strength,tenacity,yarn’s hairness,yarn’s evenness and yarn’s twisting.All the analyses were accomplished at Laboratório de Mecânica dos Fluidos and at COATS Corrente S.A.,where,it was possible to use the equipments which were fundamental to develop this paper,such as the STATIMAT ME that measures strength,tenacity,Zweigler G566 that measure hairiness in the yarn,a skein machine and a twisting machine.The analysis revealed alterations in the yarn’s characteristics in a direct way,for example,as moisture and temperature were increased,the yarn’s strength,tenacity and hairness were increased as well.Having the results of all analysis,it is possible to say that with a relatively low temperature and a high humidity,cotton yarns have the best performance.展开更多
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.
文摘Cotton,a hydrofilic textile fiber,has unstable characteristics and,for this reason,it varies its properties according to the environment changes.Moisture and temperature are the two most important factors that lead to a cotton spinning sector and influence its quality.Those two properties can change the entire spinning process.Understanding this,moisture and temperature must be kept under control when used during the spinning process,once the environment is hot and dry,the cotton yarns absorb moisture and lose the minimal consistency.According to this information,this paper was developed testing four types of cotton yarns,one kind of cotton from Brazil and the others from Egypt.The yarns were exposed to different temperatures and moisture in five different tests and in each test,six samples were examined through physical and mechanical tests:resistance,strength,tenacity,yarn’s hairness,yarn’s evenness and yarn’s twisting.All the analyses were accomplished at Laboratório de Mecânica dos Fluidos and at COATS Corrente S.A.,where,it was possible to use the equipments which were fundamental to develop this paper,such as the STATIMAT ME that measures strength,tenacity,Zweigler G566 that measure hairiness in the yarn,a skein machine and a twisting machine.The analysis revealed alterations in the yarn’s characteristics in a direct way,for example,as moisture and temperature were increased,the yarn’s strength,tenacity and hairness were increased as well.Having the results of all analysis,it is possible to say that with a relatively low temperature and a high humidity,cotton yarns have the best performance.
