The yield characters and quality characters of several new cotton varieties in the mid-south area of Hebei Province were comprehensively evaluated in this pa- per. In different ecological environments, the single-boll...The yield characters and quality characters of several new cotton varieties in the mid-south area of Hebei Province were comprehensively evaluated in this pa- per. In different ecological environments, the single-boll weight of tested cotton vari- eties had the biggest variation coefficient among yield characters and micronaire value had the biggest variation coefficient among fiber quality characters. Path analy- sis indicated that the direct path coefficients of various characters had the flowing order, lint percentage〉 number of bolls per plant〉 single-boll weight〉 seed index among yield components and uniformity index 〉 fiber specific strength〉 micronaire value〉 elongation rate〉 upper half staple length among fiber quality characters. Principal component analysis indicated that the top three principal components contributed 8.263% of accumulated variance, basically reflecting the vast majority of informations of 10 main characters in tested cotton varieties.展开更多
To improve the accuracy of the vehicle crashworthiness simulation, it is necessary as well as important to integrate the valid forming effects of key parts. It has been agreed by many that one-step simulation results ...To improve the accuracy of the vehicle crashworthiness simulation, it is necessary as well as important to integrate the valid forming effects of key parts. It has been agreed by many that one-step simulation results should be used only as a qualitative trend of the part but not as an engineering result for further structural analysis, especially for a relatively complex part. The study shows that it is inaccurate to analyze the forming effects with one-step simulation based on the geometry of the final part through comparison with the incremental simulation and verification with the actual part, whether in thickness or in plastic strain. However, incremental simulation is very time consuming and infeasible in the early stage of vehicle design due to lack- ing of forming tools and process parameters. An engineering approach is proposed to meet the requirement of accuracy as well as the time efficiency, where one-step simulation is conducted based on the geometry of the transformed part instead of the fi- nN part. The geometry of the transformed part is generated by simple die design engineering and proves to offer much more accuracy than the one-step simulation based on the final part geometry.展开更多
基金Supported by Project of Cotton Industry Technology System in Hebei of National Science-technology Support Plan(2009BADA3B01)~~
文摘The yield characters and quality characters of several new cotton varieties in the mid-south area of Hebei Province were comprehensively evaluated in this pa- per. In different ecological environments, the single-boll weight of tested cotton vari- eties had the biggest variation coefficient among yield characters and micronaire value had the biggest variation coefficient among fiber quality characters. Path analy- sis indicated that the direct path coefficients of various characters had the flowing order, lint percentage〉 number of bolls per plant〉 single-boll weight〉 seed index among yield components and uniformity index 〉 fiber specific strength〉 micronaire value〉 elongation rate〉 upper half staple length among fiber quality characters. Principal component analysis indicated that the top three principal components contributed 8.263% of accumulated variance, basically reflecting the vast majority of informations of 10 main characters in tested cotton varieties.
基金supported from the National Natural Science Foundation of China (Grant No. 51005144)the Innovation Program of Shanghai Municipal Education Commission and Shanghai Automotive Industry Science and Technology Development Foundation (Grant No. 1009)
文摘To improve the accuracy of the vehicle crashworthiness simulation, it is necessary as well as important to integrate the valid forming effects of key parts. It has been agreed by many that one-step simulation results should be used only as a qualitative trend of the part but not as an engineering result for further structural analysis, especially for a relatively complex part. The study shows that it is inaccurate to analyze the forming effects with one-step simulation based on the geometry of the final part through comparison with the incremental simulation and verification with the actual part, whether in thickness or in plastic strain. However, incremental simulation is very time consuming and infeasible in the early stage of vehicle design due to lack- ing of forming tools and process parameters. An engineering approach is proposed to meet the requirement of accuracy as well as the time efficiency, where one-step simulation is conducted based on the geometry of the transformed part instead of the fi- nN part. The geometry of the transformed part is generated by simple die design engineering and proves to offer much more accuracy than the one-step simulation based on the final part geometry.
