• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.273-277
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• 2004

Variation in the size of the silk filament will determine the uniformity and quality of the silk reeled. In the present study, an attempt has been made to study the filament size variation in 6 multivoltine parental breeds and 9 multivoltine ${\times}$ bivoltine hybrids in all three seasons of a year. All multivoltine breeds and multivoltine ${\times}$ bivoltine hybrids showed variation in filament size throughout its length from the outer layer to inner layer. Results of the present study indicated that the size of the filament decreased from outer to inner layer. The decrease in filament size was sudden in some breeds/hybrids whereas it was gradual in other. Relationship between filament length to that of slope, average filament size to slope, and maximum filament size to slope was determined based on regression analysis. Regression analysis revealed significant positive correlation between slope vs average filament length (r=0.92$^{**}$) in multivoltine${\times}$bivoltine hybrids. Among parental breeds, 96C showed lowest slope of the curve (b-value: -0.00428) and 96A showed highest slope of the curve (b-value: -0.00269). Among 9 hybrids, PM${\times}$N $B_4$ $D_2$ recorded lowest slope value (b-value: -0.00328) and BL24${\times}$N $B_4$ $D_2$ showed highest value for slope of the curve (b-value: -0.00234). The breed 96C, which showed lowest slope value can be utilized for future breeding programmes to breed strains with less size deviation. Three multivoltine${\times}$bivoltine hybrids viz., PM${\times}$N $B_4$ $D_2$, 96E${\times}$CSR19 and BL67${\times}$CS $R_{101}$ , which showed less slope values (b-values: -0.00328, -0.00300 and -0.00297 respectively) can be utilized for commercial exploitation to produce uniform silk.k.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.44-52
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• 2002

To understand the relationship among different quantitative traits, correlation studies were performed by utilizing eighty-eight inbred strains of silkworm, Bombyx mori L. on twelve economic characters. Analysis resulted in correlation of 5th instar period with total larval period (r ＝ 0.7882), cocoon weight with shell weight (r ＝ 0.8326), shell weight with shell ratio (r ＝ 0.5067), shell ratio with raw silk ％ (r ＝ 0.7570), raw silk ％ with filament length (r ＝ 0.3490), filament size (denier) with reelability (r ＝ 0.3193) and boil-off loss % (r ＝ 0.2792). Negative correlation was observed among filament length with filament size (r ＝ 0.7582) and reelability with boil-off loss % (r ＝ -0.3236). Correlation of different quantitative characters for quality silk production is discussed.

• Journal of Fashion Business
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• v.8 no.6
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• pp.68-77
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• 2004

Hollow filament yarns provide better warmth to the touch, lighter in weight, increased opacity, and subtle luster compared to the regular synthetic filament yarns. However, luster properties of textile fibers or fabrics are often difficult to characterize, partly due to the fineness of the surface texture, the anisotropic nature of the weave structure, the complexity of the fiber array comprising a yarn, and the fiber structure itself. In this study, the fabric surface luster image was analyzed using image analysis methods after image acquisition. The hollow filament fiber was modeled using a three-dimensional modeling software. It was then ray-traced for comparing the virtual luster images of the hollow fiber and the regular fiber models based on shading models including photon mapping. The luster object size of the actual hollow filament fabric was smaller than that of the regular filament fabric. The shape of the luster object of the hollow filament fabric was dual peak type while that of the regular filament was single.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.44.4-45
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• 2015

We investigate the properties of galaxies belonging to the filaments in cosmic void regions, using the void catalogue constructed by Pan et al. (2012) from the SDSS DR7. To identify galaxy filaments within a void, voids with 30 or more galaxies are selected as a sample. We identify 3067 filaments in 1050 voids by applying the filament finding algorithm based on minimal spanning tree and reducing processes to spatial distribution of the void galaxies. We study the correlations between galaxy properties and the specific size of filament which quantifies the degree of the filament straightness. For example, the average magnitude and the magnitude of the faintest galaxy in filament decrease as the straightness of the filament increases. We also find that the correlations become stronger in rich filaments than in poor ones with fewer member galaxies. We discuss a physical explanation to our findings and their cosmological implications.

• Composites Research
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• v.24 no.5
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• pp.1-8
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• 2011

This paper presents the results of theoretical analysis and experimental test to show the size effect on the fiber strength of filament would pressure vessel. First, a series of fully scaled hoop ring tests with filament would carbon-epoxy were conducted, which exhibited a remarkable size effect on the fiber strength. Next, the failure analyses using WWLM(Weibull Weakest Link Model) and the SMFM(Sequential Multi-step Failure Model) were performed and compared to the hoop ring test data, as well as to unidirectional specimens test data from the literature. It was found that the analysis results significantly underestimated the fiber strengths compared to the test data. In this study, a modified SMFM was proposed through the modification of the length size effect. The fiber strengths from modified SMFM analysis showed good agreement with the test data.

• International Journal of Industrial Entomology and Biomaterials
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• v.24 no.1
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• pp.17-21
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• 2012

The effect of cultivation season on the cocoon filament quality of authorized silkworm variety, GoldenSilk was examined with cocoon filament character, reeling character, and fiber character during 3 years. In cocoon filament character, filament length of spring and autumn cocoon was 979 and 879 m, respectively. Cocoon filament weight of spring and autumn cocoon was 33.1 and 26.5 cg, which is lower than that of general bivoltine strain, BaeGokJam. Raw silk percentage of spring and autumn cocoon was 15.65 and 13.77%, respectively. In reeling character, reelability showed similar trend regardless of cultivation season and strain. However, the length and weight of non-broken filament of spring season were slightly higher than those of autumn cocoon. Cultivation season did not affect on the fiber characteristics such as clearness and neatness, lousiness, and degumming loss. In cocoon character, filament length, size, and weight, spring cocoon filament showed higher value than autumn cocoon, but lower than authorized general silkworm varieties. In reeling characteristics, non-broken length and weight showed the similar trends with the cocoon filament character. However, the reelability of GoldenSilk cocoon was not affected by cultivation season. The reelability of GoldenSilk cocoon was also similar with that of authorized general one. Fiber character including clearness and neatness, lousiness, and degumming loss was also similar regardless of the rearing season and different strain.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.101-105
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• 2004

A number of Chinese, Japanese and European silkworm strains with coarse size filament were used for breeding the coarse size variety. Through cross breeding combined with pedigree selection within thirteen generations, a pair of coarse size silkworm variety, named ${CU_1}{\times}{CU_2}$, was obtained after five years. Laboratory trials showed that the filament size of its 4F_1$ hybrid was over 4.3 D, and the other economic characters were also good.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.135-139
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• 2002

By means of correlation analysis and path coefficient analysis, 18 characteristics of 325 conserved silkworm races were studied for the selecting efficiency on main silk quality characteristics. The result showed that selecting lines with heavier cocoon weight are beneficial to raise the weight of have. Choosing strains with higher cocoon shell percentage, longer filament length and better reelability percentage is good for increasing non-broken filament length. Selecting lines with medium daily weight of have produced in the fifth instar, medium cocoon shell percentage and simultaneously selecting heavier cocoon shell weight are favorable to promote reelability percentage. Choosing strains with heavier cocoon weight, higher cocoon shell percentage, heavier daily weight of bave produced in the fifth instar and heavier weight of bave but shorter filament length may hopefully breed out a race with thick filament size. And selecting strains with heavier weight of have and fine filament size are beneficial to increase filament length. Selecting lines with higher cocoon shell percentage and heavier weight of bave are favorable to raise raw silk percentage of cocoon. There are no significant direct or indirect correlation coefficient between viability and major characteristics of silk quality. It is, therefore, feasible to breed a silkworm race with excellent vitality and good silk quality as well.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.61-68
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• 1999

The variety of crystalline structure and mechanical properties of PP filament treated with dry heat treatment at different draw ratio has been studied. Crystalline structure and mechanical properties of annealed PP filament at different draw ratio has been examined by XRD, UTM, and density method. Heat treatment has been carried out $100^{\circ}C$, $120^{\circ}C$ $140^{\circ}C$ for 30min. in dry oven. From the results of this study, it found the following facts. It was found that the crystallinity and crystallite size of (110) plane of sample were increased with increasing of annealed temperature and draw ratio. The crystalline form of annealed sample which was undrawn showed ${\alpha}$, ${\beta}$ mixing form below $120^{\circ}C$ and showed ${\alpha}$ form at $140^{\circ}C$. But the crystalline form of annealed sample which was drawn showed ${\alpha}$ form at $120^{\circ}C$. Initial modulus and tensile strength were increased with increasing of annealing temperature, and the degree of orientation was decreased with decreasing of annealing temperature.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.150-157
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• 1998

This study was carried out to define the effects of anti-juvenile hormone analogue(AJH) treatment at different silkworm larval stages on some silk filament properties. It was revealed that the treatments at the 1st and 2nd days of the 3rd instar as well as the 1st day of the 4th instar resulted to trimolters induction without lethal effect. The trimolters induced by treatment at the 1st day of the 4th instar showed the shortest larval duration and the lowest single cocoon weight, cocoon shell ratio, cocoon size, single filament length and denier of filament compared with those of the control, while the trimolters induced by the 3rd-instar treatment showed intermediate values. All treatments showed no significant differences from the aspect fo degumming ratio, elongation rate and crystallinity index of fibroin. However the silk filament obtained from the treatment at the 1st day of the 4th instar showed the highest tenacity which was revealed to be related to the better uniformity of filament by the means of microscopic photographing. FT-IR spectroscopy of the silk fibroin showed a sharp and strong peak at the position of 794.72 cm-1 in all AJH-treated samples regardless of trimolters induction, which was absent in control.