• Textile Coloration and Finishing
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• v.22 no.2
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• pp.163-172
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• 2010

In order to investigate the changes in mechanical properties of sanitary nonwoven fabrics actually used as a top sheet, the fabric was treated with a mixture of chitosan and nanosilver colloidal solution in accordance with the prescribed ratio. The former is a natural polymer with excellent biocompatibility and the latter can give an additional performance while compensating the weaknesses of chitosan of deteriorating adherence efficiency. It was shown that the bending and shearing characteristics of the chitosan/nanosilver treated fabrics decreased, which helped to make it softer, smoother and more flexible. The shape stability and drapability of the treated fabrics improved. As KES-FB system evaluation showed that Koshi was deduced, and both Numeri and Fukurami were increased. Thereby, the chitosan/nanosilver treated fabrics were smoother to provide elasticity. In the change of hand value compared to chitosan only treatment, a better THV was shown in the fabrics treated with chitosan/nanosilver mixed solution than the fabric treated with chitosan alone.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.85-85
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• 2013

A ceramic coating material with nano-sized silicon oxide on AISI 4340 steel for a thermal conductor at a high temperature was analyzed to find an optimum coating process. Average surface roughness of the coating layers prepared by dipping process was about $5.26{\mu}m$. Potassium silicate addition as a binder of the coating material tended to improve its hardness. A pencil scratch hardness testing showed that a loading more than 800 g made fragments of the coating layer.

• Journal of Power System Engineering
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• v.12 no.3
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• pp.32-37
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• 2008

The present work aims to determine the overall pressure losses in the shell from the point of entry of the fluid to the outlet point of fluid of shell and tube heat exchanger. The main contribution of the present work is concerned with calculating the pressure drop in the interior section and window section. Shell-side flow velocity distributions have been evaluated. We assume that the shell-side fluid is turbulent. The calculation procedure is based upon the Delaware method. Evaluation of pressure drop on the shell side will be helpful for a designer or manufacturer of a heat exchanger.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.331_332
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• 2009

1979년 Nancy Wertheimer와 Ed Leeper가 수행한 연구결과에서 자기장이 소아백혈병에 의한 사망률을 높일 수 있다는 가능성을 발표한 이후, 인체건강에 유해한지에 대한 많은 궁금증이 증가해 왔다. 이후 일부 검증되지 않은 연구결과를 여과없이 인용 보도함으로써 대다수 국민이 오해하고 막연한 불안감을 갖게 된 측면이 있으며, 전기의 소중함은 누구나 인정하면서 전력시설 인근 주민은 자계에 대해 염려하며 건설반대, 전력설비 이전 등 극저주파전자계의 피해를 우려하고 있는 실정이다. 본 고에서는 국내 송전선로 극저주파자계의 노출현황을 살펴보고, 2007년 6월 세계보건기구(WHO)가 발표한 극저주파전자계와 인체건강의 관계 검토를 마무리한 공식보고서(Fact sheet No.322)를 고찰하고자 한다.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.16-25
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• 2000

The influence of four process parameters of soft nip calendering including calendering pressure, temperature, moisture content and nip residence time on bulk, smoothness and tensile strength of newsprints has been investigated. In addition, the effect of basis weights on calendering responses has been examined. Bulk of newsprints decreased and smoothness increased with the increase of the calendering pressure, temperature, moisture content of the sheets and nip residence time. Improvement in tensile strength was observed when low calendering pressure and high temperature of heat-ing roll were employed. Tensile strength of the newsprint, however, decreased abruptly when the calendering temperature and pressure increased above certain levels due to the rupture of sheet structure, which has been verified by SEM. SEM micrographs also showed that it would be possible to maintain the inner bulk while densifying the fibers on the outer surface of newsprint by adjusting the soft nip calendering variables properly.

• Journal of Engineering Education Research
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• v.15 no.5
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• pp.47-53
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• 2012

Practical problem-solving studies in a company or organization have provided great advantages for our university and students. For example, such studies can lead them to build a stronger relationship with local governments and companies as well as develop their research through collaborative studies. On the other hand, comments from companies or organizations that accepted our students showed that they did not always have advantages. This study seeks ways to establish a sustainable long-term internship program that can offer advantages for companies. Advantages and disadvantages of the internship are written by the company on the evaluated sheet. These feedback comments are analyzed by text-mining approach. It is shown that there are three types of company and organizations depending on their reasons for accepting students. Next, suitable internship programs for each type, including their period and expense distribution are presented.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1586-1589
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• 2007

The influence of optical components constituting the backlight of TV on the luminance property of backlight was analyzed. The variation of luminance when the light emitted from light source passes each optical part was evaluated.

• Transactions of Materials Processing
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• v.15 no.4 s.85
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• pp.281-288
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• 2006

Most of automobile member parts experience severe springback problems because of their complicated shape and high yielding strength. Now it becomes imperative to develop an effective method to resolve these problems. However, there remain several obstacles to get accurate estimation of dimensional shape. Especially the effective algorithms to simulate sheet metal forming processes including drawing, trimming, flanging and springback is demanded for the multi stage simulation of automobile member parts. In this study, for the purpose of accurate springback calculation, a simulation program which is robust in springback analysis is developed. Favorable enhancement in computation time for springback analysis by using latest equation solving technique and robust solution convergence by continuation method are achieved with the program. In analysis, the multi processes of rear side member are simulated to verify the system. For the evaluation of springback accuracy practically, all conditions including boundary conditions for springback analysis and inspection conditions for dimensional accuracy are applied. The springback results of simulations show good agreement with the experiments.

• Journal of the Ergonomics Society of Korea
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• v.15 no.2
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• pp.51-62
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• 1996

This research utilized the psychophysical methodology, where secrw drivers are used, to determine the effects of i) the location and orientation of work objects, and ii) wearing gloves, on ratings of perceived exertion at various body parts. The validity of the psychophysical methodology in determining a preferred work pace was also studied. The subjects drove screws with a screw driver into thick wooden sheet at three vertical and three horizontal locations. They drove serews for 3 minutes at each location and assessed the condition using the psychophysical scale. The results showed that only the vertical location was a significant factor in determining the discomfort ratings. Driving screws at elbow height on the vertical surface and with the lower arm close to the body on the horizontal surface were the work locations with the smallest ratings of perceived discomfort. Wearing gloves had significant effects on reducing the pain of the hand. From the experiment in which a comfortable work pace was identified using 20 minute psychophysical adjustment, it was found that the psychophysical method is sensitive to workers perception of the physical stress when the upper limbs are employed. This was confirmend by the high correlation between the psychophysical results and EMG measurement.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.331-334
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• 2003

Since regulation or specification for the reinforcing method are quite ambiguous, structural design for the reinforcement can be subjectively and arbitrarily conducted. Thus, reasonable limitation and guide for the quantity of the reinforcement are required for the safe use of the structure after repair. In order to guarantee the safety of the structural member several items should be considered; reinforcing limit to avoid the brittle failure, least required strength of the existing member before reinforcement in order not to fail under the new serviceability load condition when reinforcing steel plates or CFRP sheets are harmed or subjected to fire.