• 식물병연구
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• 제10권3호
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• pp.203-208
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• 2004

붉은 고추 탄저병균의 우점종인 Colletotrichum gloeosporioides는 C. acutatum에 비해 병원성이 강하였다. C. gloeosporioides는 G와 R계통이 존재하였으며, G계통이 R계통보다 더욱 강한 병원성을 보였다. 붉은 고추 품종간의 병원성 검정 결과, 금세기 품종이 가장 감수성이었고, 파페트 품종이 가장 약한 감수성이었다. 참깨, 홍화, 마, 그리고 딸기와 같은 다른 기주에서 분리되어진 C. gloeosporioides는 붉은 고추에 감염을 일으켰다.

• 한국염색가공학회지
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• 제12권2호
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• pp.89-95
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• 2000

Effect of twist-setting time, temperature and cylinder layer for the physical properties of the twist yarn were investigated by separated 9 layer from yarn cylinder. Obtained results were as follow. Shrinkage of the yarn in middle layer shows high value with heat-permeation and in inner's shows low value because of cylinder hardness. And then yarn thermal shrinkage in outer layers shows more or less high value because twist yarn in the outer layer sets more faster. Concerning to the difference on the yam physical properties among cylinder layers, the changes on physical properties shows significant differences from the 7th layer to the last one. Linear density, T.P.M and initial modulus decreases but snarl index increases.

• 감성과학
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• 제5권3호
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• pp.35-38
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• 2002

Random and/or periodic defects occur in all spun yarns. These irregularities can often lead to defects in finished fabric. Yarn evenness tests are used to obtain statistical data about yarn properties, such as CV%, which is useful in comparing several sets of similar data that differ in mean value but may have some commonality in relative variation. Although this statistical data is helpful in determining relative yam quality, accurate predictions of how the yarn will appear in fabric form are still difficult to obtain. As an promising alterative, wavelet analysis has been employed to localize yarn defect so as to predict the visual qualities of the fabrics.

• Communications for Statistical Applications and Methods
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• 제13권1호
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• pp.191-204
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• 2006

This paper develops a Bayesian method to derive the optimal sequential preventive maintenance(PM) policy by determining the PM schedules which minimize the mean cost rate. Such PM schedules are derived based on a general sequential imperfect PM model proposed by Lin, Zuo and Yam(2000) and may have unequal length of PM intervals. To apply the Bayesian approach in this problem, we assume that the failure times follow a Weibull distribution and consider some appropriate prior distributions for the scale and shape parameters of the Weibull model. The solution is proved to be finite and unique under some mild conditions. Numerical examples for the proposed optimal sequential PM policy are presented for illustrative purposes.

• 한국염색가공학회지
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• 제16권1호
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• pp.5-9
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• 2004

This research surveys the threadline instability on the belt texturing machine according to the 1st heater temperature, draw ratio and velocity ratio. the threadline instability to the time, which is called surging phenomena, is analysed with variations of draw ratio and velocity ratio. In addiction, the surging phenomena is investigated with the variation of the untwisting tension and false twist mechanism on the belt texturing machine. The breaking strain, modulus and yam unevenness of the DTY along the yarn length are measured and analysed with the surging phenomena which is due to untwisting tension variation on the threadline according to the draw ratio, 1st heater temperature and velocity ratio.

• Fibers and Polymers
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• 제6권1호
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• pp.42-48
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• 2005

The effects of opening, carding, and repeated drawings on single fiber and bundle cotton characteristics were stud­ied by employing $Mantis^{\circledR}$, $AFIS^{\circledR}$ and HVI Testers. Some of the significant changes in single fiber properties were found to be due to process parameters as well as the changes in the fiber crimps, parallelness of fibers within HVI beards, and the actual changes in the tensile properties of the fibers. The study showed that the HVI test data taken just prior to spinning had the highest correlation with the yam tensile properties. Based on the study results, we point out the potential of HVI for future quality and process control in spinning by recommending a set of expanded HVI output that is more scientific and compre­hensive for the future control needs.

• Fibers and Polymers
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• 제6권2호
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• pp.139-145
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• 2005

The paper reports the physical and mechanical properties of hand-woven carpets, which have been put under static force. Two groups of wool fibres, from two parts of Iran, were prepared to spin pile yams for the carpets. Each group of the fibres included both conventional and tanned wool. Then two yam counts, $N_m$ = 4/2 and 6/2, were spun for two different knot densities. After weaving the carpets, they were put under static force and their thickness variations were measured and plotted against time, in logarithm scale. The resiliency of the carpets piles after eliminating the static force, were measured and plotted against time, in logarithm scale, too. The results were compared to each other and analysed with respect to parameters such as the type and quality of the wool fibres as well as knot density of the carpets.

• Fibers and Polymers
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• 제6권2호
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• pp.151-155
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• 2005

A twisting machine is to twist yarns for improving yam strength. After twisting yams, the twisting machine winds yams into a bobbin. The traverse mechanism is very important part of winding mechanism. Because it performs uniform winding onto the bobbin. the traverse cam is the main part of the traverse mechanism. This paper proposes design method of the traverse cam using the relative velocity method [4,5]. The relative velocity method is used to calculate the relative velocity of the follower versus the cam at the center of roller, and then to determine the contact point using the geometric relationship and kinematical constraints. Finally, we present examples verifying the accuracy of the proposed methods.

• Fibers and Polymers
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• 제4권3호
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• pp.119-123
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• 2003

Fluff (lint, fiber fly) generation, especially related to yarn structure, was investigated. Research centered on the fiber length related to fluff generation during the knitting process. Short fiber length composing yarn structure was a main source of the fluff shedding. High quality spun yarn with longer length of fiber was recommended to the high speed knitting industry in order to reduce process troubles such as yarn breakage, etc. but the cost is doubtable to the manufacturers. A trial to reduce the fluff trouble by using chemicals to hold the short fiber on the surface of the yam was suggested and the research showed a positive effect to the problem. However, another factors including a by-product of chemical residue and searching more feasible material need to be concerned for the future research.

• Journal of Ginseng Research
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• 제27권4호
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• pp.178-182
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• 2003

Vesicular-arbuscular mycorrhizae (VAM) fungi naturally colonise American ginseng roots and this relationship is highly beneficial to enhance plant productivity. Our goal was to determine the effect of adding two Glomus species (Glomus etuticatum, G. intraradices) on survival, photosynthetic capacity, growth, morphology and root ginsenoside content of one-year-old American ginseng plants grown in a broadleaf forest. While our study revealed that VAM inoculations significantly affected root morphology and Re ginsenoside content, the survival, photosynthetic capacity and root growth of American ginseng plants were not significantly influenced by VAM inoculations. Surface area and volume of rootlets were 16-25% higher for ginseng grown in VAM-inoculated soil compared to those grown in the control plots. Also, Re ginsenoside content was 18 ％ higher in YAM-inoculated roots compared to controls.