• Title/Summary/Keyword: nature exposure

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Studies on Silk Textile Wash and Wear Finishing (絹織物 Wash and Wear 加工硏究)

  • Choe, Byong-Hee;Lee, Yang-Hoo
    • Journal of Sericultural and Entomological Science
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    • v.23 no.1
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    • pp.47-55
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    • 1981
  • Silk textile finishing has been studied for many years by many workers in order to meet more utilities for various endusers. Such studies, however, could not be successful because any natural fibers are hardly change their natures by artificial treating methods. Textile finishing is of course to improve the mechandise qualities and the poor natures of silk so that it may be available as the best textile fiber in the world. Sometimes, famous trade marked textile plays more power than its quality in the silk market, nevertheless, this should be over line of research activities. Meantime, the silk demand has been also transferred from ladies stocking to other clothes since nylon or other synthetic fibers were developed. That is why, the extension of silk demand should be developed by various research works. Specially, silk is known as difficult textile to handle it during washing or ironing process which happened to depress down the silk usage for house wives. In order to solve such problems, the reporter has been worked for many years and now, he believes that he has developed a proper finishing method to coversuch problems. The developed finishing method may be said to eligible with economical aspect and shorten the dry duration after water washing in half against normal silk textile without harming the specific silk nature. As all of us know, silk fiber starts to denature since it was spinned by silkworm and the fiber is formed as overlapped "S" type curves during its concooning process. After it is made as raw silk or sericin silk, it shows as straight line form, but it changes in to waved form in case refining or degumming process in order return to its original spinned form. Such nature is continued during its textile form and ends with hard ironing nature than other textile fibers. Mean while, the silk fiber keeps to continue its denaturing and this is iniciated by repeat of washing and drying which takes many years to reach its final stage, The reporter has found the iniciating denature of silk by his finishing process, with out heat, decreasing the swollen nature which ended with shortening the drying duration after wash. Each washing was carried out by soaking the previously weighed sample in cold water for one hour, then pressed the sample for ten minutes to eliminate its free water component before weighing with same condition. According to this, the treated silk showed much denaturing after the finishing, but the standard silk progressed the denaturing by and by with the repeat of washing and drying, finally reached the same swollen degree of treated silk, Such treating result explains that the treated silk happened to be stebilized nature by the treating immediately. On the other that the treated silk happened to be stebilized nature by the treating immediately. On the other hand, standard silk may reach to such condition by the time of worn out clothes after repeat of washing and drying for many years while the clothes will be no more useful. The decreased swelling nature has brought about the drying period in half against standard silk after all. Not only the tests of tenacity and elongation but also crease resistance recovery, stiffness and shrinkage tests were carried out after each washing and drying which he has found better result on the treated silk textile against the standard silk. The most important thing was to keep the textile feeling of silk by such finishing work before improve any poor nature of silk. The general silk has a nature to absorb smoke or dirt from its surrounding air and reaches to dirty color shade upon such exposure, but the treated one has improved such nature because of its artificial denaturing, another word, it keeps clean longer than the normal silk. Many previous finishing works could improve some specific nature of silk, but it happened to deprave other important natures. The reporters work is, however, specialized to improve the silk to be useful as Wash and Wear Silk without harming its standard natures. So far, this work happened to be a overall innovative finishing method of silk textile.

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DDT Reduced Testosterone and Aromatase Activity Via ER Receptor in Leydig Cell (DDT의 Aromatase 증가에 의한 Testosterone 감소효과)

  • Lee, Kyung-Jin;Wui, Seong-Uk;Jin Heo;Kim, Sun-Hee;Jeong, Ji-Yeon;Lee, Jong-Bin
    • Environmental Analysis Health and Toxicology
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    • v.18 no.2
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    • pp.95-100
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    • 2003
  • Dichlorodiphenyltrichloroethane (DDT), is a widespread environmental pollutant. In this study, we investigated the effect of DDT on testosterone production through aromatase and investigated its molecular mechanism in testicular leydig cell, R2C. We investigated that the effects of DDT on testosterone production and its effects on aromatase activity in R2C cell by radio immunoassay (RIA). As the results, the potent leyding cell activator LH increased testosterone production compared to the control. DDT exposure significantly decreased testosterone production in R2C cell and DDT alone affected T reduction in a dose-dependent manner in R2C cell slightly. In addition, DDT was found to increase aromatase activity in R2C cell in a dose dependent manner. In order to assess whether the suppressive effects of DDT on LH-inducible testosterone production might be influenced by the ER, ICI 182.780, a pure antiestrogen, was used, and it was found that these inhibitory effects of DDT were antagonized by ICI 182.780, implying that the ER mediates the suppressive effects of DDT. Furthermore, the inducible effects of DDT on aromatase might be influenced by the ER, ICI 182.780 was used, and it was found that these enhancing effects of DDT were antagonized by ICI 182.780, implying that the ER mediates the inducible effects of DDT. Our results indicated that DDT inhibition of LH-inducible testosterone production in R2C is mediated through aromatase. However, the precise mechanisms by which DDT enhance in leyding cell remains unknown. The current study suggests the possibility that DDT might act as a modulator aromatase gene transcription.

The concentrations of airborne dust in non-metallic products factories and problems associated with the application of the occupational exposure limits (비금속광물 제품제조업에서 발생하는 분진 농도와 분진 노출기준 적용에 따른 문제점 고찰)

  • Kim, Hyunwook;Phee, Young Gyu;Won, Jung Il;Ko, Won Kyung;Roh, Young Man;Shin, Chang Sub
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.10 no.1
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    • pp.104-114
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    • 2000
  • This study was carried out to estimate current status of dust concentrations in the factories producing non-metallic products in Korea. Data were gathered from the environmental monitoring reports by 40 workplace environmental monitoring institutes and the questionnaire designed for the study by the authors. A total of 1838 dust samples from 368 plants were obtained from the reports and were analyzed with no data modifications. But data on asbestos, rock wool, and welding fumes were excluded in this evaluation. The factories were classified into eight groups according to the standard industrial classification scheme in Korea. The results of this study were as follows; 1. The factories included were glass, non-refractory ceramic, refractory ceramic ware, structural non-refractory clay and ceramic, cement and lime, articles of concretes, and stone. Mean(geometric mean) concentrations of total dust samples ranged from $1.75(0.84)mg/m^3$ to $5.87(2.84)mg/m^3$. Statistically significantly higher dust concentrations were found in the cement and lime industries compared with other industries. 2. The non-compliance rates were 15.2% in glass and 20.6% in other non-metallic mineral products industries. Although all institutions surveyed utilized the identical sampling and classification scheme for dusts as specified in the current occupational exposure limits, wide discrepancies were found in collecting samples and classifying dusts. Further problems were discovered in classifying dusts. A dust sample collected could be classified into any of the three groups regardless of silica content. The results of this study showed that dust concentrations in the non-metallic products industries varied widely. Also discovered was classification errors of dust types among workplace monitoring institutes. These errors could adversely affect the results of exposure assessments and the true nature of dust hazards. Further, no institutions performed respirable dust sampling and analysis of crystalline silica. In order to correct these malpractices, current standards of occupational exposure limits should be revised and tight supervision by the Ministry of Labour be suggested.

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Development of Innovative Neutron Flux Mapping System (혁신적인 중성자 속 분포 측정 시스템의 개발)

  • 조병학;신창훈;변승현;박준영;양장범
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.60-63
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    • 2004
  • An innovative in-core neutron flux mapping system has been developed and applied successfully for service in a commercial pressurized water reactor. With the benefit of double indexing path selector (Dip $s^{ⓡ}$) mechanism, the reliability of the detector drive system has been improved five times higher than that of conventional systems, and the problems caused by the serious friction generated between the detector cable and guide tubing has been solved completely because the Dip $s^{ⓡ}$ architecture allows the detector guide tubings to have larger curvature and shorter length in nature. The simple and fast maintenance is particularly emphasized in the detector drive system to secure minimum radiation exposure to the maintenance personnel by optimizing the number of components and providing easy access to the components. The programmable logic controller based digital controller with Window $s^{ⓡ}$ based operator s console provides fully automated and user friendly operation and maintenance support means.

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A Study on the Development of Chalcogenide-based ReRAM{Resistance RAM) Device with Holographic Lithography Method (Holographic Lithography 방법을 적용한 Chalcogenide-based ReRAM(Resistance RAM) 소자의 개발에 관한 연구)

  • Nam, Ki-Hyun;Chung, Hong-Bay
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.12
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    • pp.1014-1017
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    • 2009
  • In this study, we studied the nature of thin films formed by holographic photodoping chalcogenide thin films with for use in programmable metallization cell devices(PMC), a type of ReRAM. We formatted straight conduction pathway from the internal interferences of the diffraction gratings which is builded by the holographic lithography method. We investigated the resistance change of solid-electrolyte chalcogenide thin films varied in the applied voltage bias direction from about $1\;M{\Omega}$ to several hundreds of $\Omega$. The switching characteristics of the devices applied holographic lithography method was more improved than ultraviolet exposure condition. As a result of improved resistance change effects, we can analogize that the diffraction gratings is a kind of pattern for straight conduction pathway formation inside the chalcogenide thin films.

Cross-cultural Study on Knowledge Sharing in Open Collaboration: Collectivism vs. Individualism (문화에 따른 개방형 협업 지식공유 활동 비교 연구: 집단주의 문화와 개인주의 문화를 중심으로)

  • Baek, Hyunmi;Lee, Saerom
    • Knowledge Management Research
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    • v.19 no.2
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    • pp.133-150
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    • 2018
  • To cope with the rapid changes in the corporate environment, the creation of innovative output through various forms of collaboration have been discussed. For open collaborations, contributors who distribute to various countries and cultures are able to share knowledge via the internet without physical rewards or responsibilities. In this study, we focused on the open source software project, which is a representative open collaboration. We investigated the factors that affect the knowledge contribution of developers of various countries within the open collaboration platform. Specifically, we investigated the open collaborative nature of multi-culture developers by dividing cultures according to collectivism and individualism. We collected data on 26,604 developers using a python based web crawler for GitHub which is an open source software development platform, and conducted cross-cultural study. This paper contributes to the field of knowledge management by suggesting various impacts of antecedents such as hireability, and information exposure on knowledge sharing according to culture.

Students' Perspective (Stream Wise) of Parameters Affecting the Undergraduate Engineering Education: A Live Study

  • Kumari, Neeraj;Kumar, Deepak
    • Asian Journal of Business Environment
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    • v.6 no.1
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    • pp.25-30
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    • 2016
  • Purpose - The study aims to examine the students' perspective (stream wise) of parameters affecting the undergraduate engineering education system present in a private technical institution in NCR, Haryana, India. Research design, data, and methodology - It is a descriptive type of research in nature. Questionnaire Based Survey has been used to collect the data. The sample size for the study is 500 comprising of the students respondents. The sample has been taken randomly and the questionnaire was filled by the students (pursuing B. Tech) chosen on the random basis from a private technical educational institution in NCR, Haryana, India. For data analysis and conclusion of the results of the survey, statistical tool like F test was performed with the help of high quality software; SPSS. Conclusion - Analysis of variance revealed statistically no difference between the mean number of the groups (stream wise) for the parameters "Selection", "Academic Excellence", "Infrastructure", "Personality Development and Industry Exposure" and "Management and Administration". While Analysis of variance revealed statistically difference between the mean numbers of the groups for the parameter "Placements".

An Exposure Experiment for the Evaluation of Corrosion Properties of Sewage Concrete Covered with Antibiotics (항균제를 도포한 하수시설 콘크리트의 생화학적 부식특성 평가를 위한 폭로시험)

  • Roh, Kyung-Min;Lee, Eui-Bae;Kim, Young-Duk;Lee, Byoung-Ky;Kim, Gyu-Yong;Kim, Moo-Han
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.73-76
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    • 2006
  • Sewage facilities mainly consisted of concrete structures are being deteriorated seriously by biodeterioration originated from sulfur-oxidizing bacteria. To prevent biochemical corrosion of the sewage concrete, antibiotics which prevent growth of sulfur-oxidizing bacteria were developed. Recently, to evaluate biochemical corrosion properties of concrete, antimicrobial performance and resistance to sulfuric acid were investigated respectively. But, in this study, to evaluate it complexly, concrete specimen covered with antibiotics were exposed in the actual sewage environment and were investigated about corrosion properties after three months. As a result, weight change ratio, nature potential and sulfuric ratio of concrete covered with antibiotics were less than plain concrete.

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Characterization of a Bacteriocin Produced by Bacillus licheniformis cy2 (Bacillus licheniformis cy2가 생산하는 박테리오신의 특성)

  • 장지윤;이현희;김인철;장해춘
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.3
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    • pp.410-414
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    • 2001
  • A new bacteriocin produced by Bacillus licheniformis cy2 was partially purified and characterized. The bacteriocin named as BSCY2 was stable in the pH range of 2.5~9.5. BSCY2 was stable below 4$0^{\circ}C$ and it retained its antimicrobial activity during long tern storage at -2$0^{\circ}C$ and -7$0^{\circ}C$. BSCY2 was inactivated 15 min exposure to temperatures over 8$0^{\circ}C$ and lost 50% of its antimicrobial activity within 2 hr at 7$0^{\circ}C$. BSCY2 was inactivated by proteinase K treatment, which indicates its proteinous nature. Direct detection of the BSCY2 band showing antimicobial activity on Tricine-SDS-PAGE suggested an apparent molecular mass of about 6,500 dalton. These characterizatics of BSCY2 are considered as potential compounds for use in bioindustry.

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Dyeing Properties of Young Superfluous Fruits of Naju Pear Trees (나주배 적과(摘果)중 유과(乳菓)의 염색성)

  • 이상필
    • The Korean Journal of Community Living Science
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    • v.15 no.1
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    • pp.27-33
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    • 2004
  • Natural dyeing means coloring with dyes extracted from plants, minerals or animals found in nature. Natural dyeing provides calm and natural colors; it has antibacterial and deodorizing qualities; and the dyeing process is environmentally friendly. This study extracted natural dyes from young fruit by thinning out the superfluous fruits of Naju pear trees, and then examined its dyeing properties, the optimal dyeing conditions, and its color fastness for practical use. The results indicated that dyeing is ideal when it had Cu mordant treatment (5% concentration at 9$0^{\circ}C$, pH 4) for 50 min. The color fastness of natural dyes with Cu mordant treatment was very excellent after rubbing and dry cleaning, and also good after exposure to perspiration, light and washing.

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