• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.2
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• pp.257-266
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• 1998

This study was conducted to examine the changes of the mechanical properties of the position in jean slacks during the wear, previously used for the wearing test, which were subjected to repeated tensile-shearing deformation using a simulated fatigue tester has been investigated and compared, by calculating both mechanical properties and hand value(HV) of these fabrics with KES-F system and the by obtaining the THV through these calculated properties. The results are as follows. 1. The fatigue phenomenon of mechanical properties was the LT, 2H B, 2HBS, MMD, SMD, RC values increased, elasticity values of tensile, bending and shearing properties, such as B, G and compression properties LC, WC were reduced. It was shown, then, that those fabrics lost their elasticity and became flexible and soft with the increase of fatigue. 2. The hand value and THV; except anterior knee from all part of KOSHI, NUMERI, FUKURAMI was decreased. 3. The fatigue phenomenon of hand value was different on the position of clothing; on the position of hip, rate of B, G smaller than other parts and KOSHI was decreased, on the part of anterior thigh was FUKURAMI was increased, on the anterior knee RC, NUMERI, THV was increased, on the posterior knee was 2HB, 2HG, 2HGS showed increasedgreater than any other part and on the hem of back, MMD was increased, but NUMERI was decreased. 4. The changing process of mechanical properties in the simulation testing by the fatigue tester has similar tendency to that of the wearing tester. It is concluded that this testing method is useful to predict the fatigue phenomena of fabrics caused by wearing.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.161-164
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• 2001

The purpose of our study was stability of tear film for Korean. In the 1970s, the major problem for the contact lens practitioner was the management of contact lens parameters. In the 1980s, oxygen permeability was the main problem in contact lens practice: now it is dry eyes. To appropriately fit the patient with contact lenses it is imperative to know in advance if the patient has a marginal dry eye. Based on the initial diagnosis appropriate care can be taken to minimize problems with the result that the patient can successfully wear contact lenses. A well known test for dry eyes is Schirmer test which has shown to be useful for diagnosing Sjogren syndrome. Biomicroscopy can often unmask numerous problems. The classical test for marginal dry eye is measuring the tear break up time(TBUT). A dry eye problem with contact lenses is often caused by the lid. If an incomplete blink is responsible for the dry eye it is possible to change the situation by blinking exercises. The result of these test, mean value of age was 22.8, mean value of blink rate was 19 times/min, mean value of Schirmer test was 25 mm/5 min, mean value of TBUT was 7.1 sec.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.14-14
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• 2001

Nitride films such as TiN, CrN etc. deposited on glass by PVD processes have been developed for many industrial applications. These nitride films deposited on glass were widely used for not only decorative and optical coatings but also wear and corrosion resistance coatings employed as dies and molds made of glass for the example of lens forming molds. However, the major problem of nitride coatings on glass by PVD process is non-uniform film owing to pin-hole and micro crack. It is estimated that nonuniform coating is influenced by a different surface energy between metal nitrides and glass due to binding states. In this work, therefore, for the evaluation of nucleation and growth mechanism of nitride films on glass TiN and CrN film were synthesized on glass with various nitrogen partial pressure by unbalanced magnetron sputtering. Prior to deposition, for the examination of relationship between surface energy and film microstructure plasma pre-treatment process was carried out with various argon to hydrogen flow rate and substrate bias voltage, duty cycle and frequency by using pulsed DC power supply. Surface energy owing to the different plasma pre-treatment was calculated by the measurement of wetting angle and surface conditions of glass were investigated by X-ray Photoelectron Spectroscopy(XPS) and Atomic Force Microscope(AFM). The microstructure change of nitride films on glass with increase of film thickness were analyzed by X-Ray Diffraction(XRD) and Scanning Electron Microscopy(SEM).

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.726-731
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• 2002

Reaction synthesis is a process to form ceramics, intermetallics and their composites from elemental powder mixture. Application of this process to a surface modification techniques has a possibilities to enable the process at a lower temperature or for a shorter time, although synthesized materials are likely to include voids and unreacted elements. This paper intend to examine the effect of Si addition to the mixture of Al and Ni on the densification of synthesized Ni-Al intermetallic compounds and to evaluate the surface properties of obtained coatings. By the Si addition, exothermic reaction temperature to form Ni-Al intermetallic was lowered to be below the melting point of Al. Si soluted $Al_3$Ni$_2$, $Al_3$Ni and $Al_{6}$Ni$_3$Si were mainly formed in the coating layer when powder mixture was heated to 973K for 300s. Besides, densification was enhanced by increasing hot press pressure, Si additions and heating rate. When the composition of eutectic Al-Si reaches 78%, void ratio of sintered compact reduced to 0.4%. It is caused by higher flowability of Al-Si liquid phase generated and its infiltration into the void. Since the hardness of NiAl(Si) compound (about 600HV) formed in the coating layer is higher than that of Ni-Al compound (about 400HV), coating layer with high density and superior wear property is obtained by hot press using reaction synthesis from Al-Ni-Si powder mixture.

• Transactions on Electrical and Electronic Materials
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• v.8 no.1
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• pp.5-10
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• 2007

Using a reference slurry, ammonium dodecyl sulfate (ADS), an anionic and environmentally friendly surfactant, was investigated as an alternative to BTA for its inhibition and lubrication characteristics. Results demonstrated that the inhibition efficiency of ADS was superior to that of BTA. Coefficient of friction (COF) was the lowest when the slurry contained ADS. This suggested that adsorbed ADS on the surface provided lubricating action thereby reducing the wear between the contacting surfaces. Temperature results were consistent with the COF and removal rate data. ADS showed the lowest temperature rise again confirming the softening effect of the adsorbed surfactant layer and less energy dissipation due to friction. Spectral analysis of shear force showed that increasing the pad-wafer sliding velocity at constant wafer pressure shifted the high frequency spectral peaks to lower frequencies while increasing the variance of the frictional force. Addition of ADS reduced the fluctuating component of the shear force and the extent of the pre-existing stick-slip phenomena caused by the kinematics of the process and collision event between pad asperities with the wafer. By contrast, in the case of BTA, there were no such observed benefits but instead undesirable effects were seen at some polishing conditions. This work underscored the importance of real-time force spectroscopy in elucidating the adsorption, lubrication and inhibition of additives in slurries in CMP.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.3
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• pp.135-149
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• 2014

Fur clothing as fashion items is expanding into casual & ladies's wear market as well as fur market. The interest of fur fashion is rising. So this study compares and analyzes the merchandising process of textile clothing also it of fur clothing by merchandising steps. Fur clothing has so many change factors at time of purchase by scarcity of raw material, price fluctuation, exchange rate and others. Therefore it is primarily about securing of raw material. As soon as plan of product is finished, the purchase of fur raw material has to be started while progress of design products for commercializing the fur clothing. The design of fur clothing is consist of material design, color design and shape design. And It makes a new trend & market as we are developing new & various treatments. The some of imported materials are transferred to the factory for being treated first dressing, fabric treatments and dyeing processing according to the design. The first treated materials are transferred to the sewing factory again for secondary treatments and finally inspected and shipped. During secondary treatments the fur has gone through various manufacturing process for using like fabric materials and it takes long time because almost work is running manually. Unlike fabric clothing, fur clothing's manufacturing method is complicated and various from material process to shape process as per feature. Therefore the merchandising with fur cannot make mass production also needs detail craftsmanship depending by expert's skills. On this wise the fur clothing takes long time to the completion thus it has been risky and costly.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2374-2385
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• 1994

SiCw/Al composite material is especially attractive because of their superior specific strength, specific stiffness, corrosion fatigue resistance, creep resistance, and wear resistance compared with the corresponding wrought Al alloy. In this study, Fatigue crack growth behavior and fatigue crack path morphology(FCPM) of SiC whisker reinforced Al 6061 alloy with 25% SiC volume fraction and Al 6061 allay were performed. Result of the fatigue crack growth test sgiwed that fatigue crack growth rate of SiCw/Al 6061 composite was slower than that of Al 6061 matrix therefore it was confirmed that Sic whisker have a excellent fatigue resistance. And Al 6061 matrix had only FCPM perpendicular to loading direction. On the other hand SiCw/Al 6061 composite had three types in fatigue crack path morphology. First type is that both sides FCPM of artificial notch are perpendicular to loading direction. Second type is that a FCPM in artifical notch has slant angle to loading direction and the other side FCPM is perpendicular to loading direction. Third type is that both sides FCPM of notch have slant angle to loading direction. It was considered that this kinds of phenomena were due to non-uniform distribution of SiC whisker and confirmed by SEM observation for fracture mechanism study.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.313-318
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• 2020

Since radon is an inert gas and is a monoatomic molecule, the size of one particle represents the size of an atom, which means that it has a radius of approximately 1 to 100 nm. Therefore, if the mask has a radius smaller than the size of general fine dust and ultra fine dust, but it is possible to block the inhalation of radon more than a certain amount, it is considered that the exposure through the inhalation of radon can be reduced through normal indoor wear. Accordingly, we would like to find out the radon blocking effect of a mask worn in everyday life. Looking at the reduction rate of radon for each mask, cotton masks decreased by 33.45%, medical masks by 33.50%, KF 80 masks by 35.12%, and KF 94 masks by 37.72%. It was found that the radon blocking effect of the cotton and medical masks was somewhat inferior to that of the KF mask, but the difference was not so great that the introduction of radon into the air could be blocked to a certain level by wearing a mask.

• Journal of Preventive Medicine and Public Health
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• v.38 no.2
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• pp.189-196
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• 2005

Objectives: An outbreak of shigellosis occurred among students and staff of S primary and middle school, Seongju-gun, in 2003. This investigation was carried out to institute an effective counterplan, and study the infection source and transmission of the shigellosis. Methods: The authors conducted a questionnaire survey among 235 students and staff from S preschool, primary and middle school relating to the ingestion of school lunch and the manifestation of symptoms. Also, the author investigated the drinking water, feeding facility and reconstructed cooking process of the food presumed to be the cause of the shigellosis. The diarrhea cases were defined as confirmed cases and those cases who had had diarrhea more than one time, accompanied with symptoms such as fever, vomiting and tenesmus. Results: From rectal swabs 20 people, between June 28 and July 4, 2003, were confirmed with shigellosis. The diarrhea attack rate was 40.0%. Those who had ingested tomatoes and cubed radish kimchi had significantly higher diarrhea attack rates (p<0.05), with the relative risk of tomatoes being 2.69 (95% CI: 0.98-7.42). The major cause of shigellosis was presumed to be from contaminated tomatoes due to cooking with rubber gloves containing holes. Conclusion: The cooks in charge of school lunches must make doubly sure to not only attend to their sanitation, but also to manage the table wear and items used in providing school lunches. The health care authority should introduce higher-leveled criteria for health care among cooks, so that they cannot cook when the have a case of any infectious disease.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.410-416
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• 2005

Rhodiola sachalinensis has been used as a traditional medicine in Asia. We were germination in vitro seedling of grow naturally in Chang bai Moutain. And callus induction from leaf segments, treatmented plant regeneration in plant growth regulators (Auxins and cytokinins). We investigated optimal conditions for efficient plant regeneration through callus induction and shoots formation on medium with various kinds of growth regulators. Callus induction and adventitious shoots formation was achieved when cytokinin and auxin combinated to this experiment. Especially, there was the highest callus induction rates when we were used to 1 mg/L kinetin and 2 mg/L NAA $(98\%)$, Adventitious shoots formation wear obtained difference rate when cytokinin alone 1 mg/L BA $(96.6\%)$. And regenerated plantlet was acclimatized and transplanted to the soil, showed $100\%$ survival.