• Journal of Advanced Marine Engineering and Technology
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• v.34 no.1
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• pp.62-68
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• 2010

The requirement of high efficiency and low emission for marine diesel engines are being enforced because of air pollution and climate change on the earth. In connection with these, many new technologies are considered. But they are mainly for new building ship. It is necessary to be concerned about the improvement of engine performance for existing ship. In this paper, the simulation program for performance of marine two-stroke diesel engine was developed to predict the deteriorating performance according to elapsed time for existing ship. The result was compared with the result of the program named TOP-CODE which was used by engine maker and checked to be shown good agreement between them.

• Journal of the Korean Geographical Society
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• v.39 no.1
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• pp.116-131
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• 2004

The purpose of this study is to inquiry spatial features of shipbuilding subcontract structures. These days, firms are trying to get their goals by wav of production system which is related to other firm. Shipbuilding subcontract structures which builds complex and grand plant show a different peculiarity according to spatial features having rules of business relations with contracting firms. First of all, internal subcontracting firms which takes part in the production process of contracting firm and shipbuilding cooperative complex firms which showing a peculiarity of spin-off firms are closely related with contracting firm. And firms in Changwon that have a specialized with machine industry and those of Busan that have made development in marine equipment industries traditionally are connected with subcontract relations because of a high level of specialization relatively. On the other hand, subcontracting firms which range from non-localized and provide standardized products are less connected with contracting firm. In order to develop of Korea' shipbuilding industry, first, close cooperative relation is important with subcontracting firms which concentrate internal and outside contacting firm. And, it is necessary to strengthen selective business relations with far distance firms which are specialized in technology.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.4
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• pp.297-308
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• 2007

The granulation equipment of concentrated wastes is manufactured for the polymer solidification of concentrated wastes. It uses liquid sodium silicate as a granulating agent for the granulating of dried powder containing boric acid. The granulating agent is sprayed in the form of droplet and mean size of dried granules is $2{\sim}4mm$. The new technology which has been used for the polymer solidification of spent resin in U.S. and certified by Nuclear Regulatory Commission (NRC) is successfully applied to concentrated wastes. This uses in-situ solidification process within drum without mechanical mixing. Maximum loading of waste can be achieved without increasing of waste volume. Polymer waste forms were evaluated with several test such as fire test, compressive strength test, leaching test, immersion test, irradiation test, and thermal cycling test according to standard test procedures.

• Research in Plant Disease
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• v.10 no.4
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• pp.279-284
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• 2004

A rust fungus has caused a serious early defoliation of Zanthoxylum schinifolium during growing seasons every year at the plantations located at Hadong and Jinju, Kyeongsangnam-Do in Korea. In order to identify the rust fungus and clarify its life cycle in Korea, aeciospores from Pinus thunbergii were artificially inoculated on the leaves of Z. schinifolium. Uredinial stage was successively formed on the leaves of Z. schinifolium. Based on the artificial inoculation test and on the morphological features of the dried specimens collected from P. thunbergii and Z. schinifolium, this rust fungus was identified as Coleosporium xanthoxyli. Morphological features of aecial and uredinial stages of the species were described. The first symptom of the infection was developed from later June to early July. And leaf infection ratio was 17.8%-58.7% during August at Hadong and Jinju regions of Kyeongsangnam-Do in Korea.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.2
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• pp.24-31
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• 2001

As a novel method to improve strength properties of recycled test liner, Condebelt press drying system was introduced and adopted into Korea. New press drying treatment could enhance the surface and strength properties in accordance with the increase of sheet density. However, Condebelt drying can not increase the density of repeatedly recycled test liner as much as that of virgin UKP and at the same density condition, the strength of Condebelt press dried UKP is greater than that of press dried test liner. In order to increase the strength of test liner, two attempts were tried in this study. First, addition of polyelectrolytes, dry strength agent was investigated with a view to promote the fiber bonding potential of reclaimed corrugated container pulp. Second, blending effect of fines were analyzed in an aims of increasing density and strength of test liner. The results were as follows; Even in the case of test liner densified by Condebelt press dryer, addition of amphoteric PAM as a dry strength agent was effective in increasing strength properties and so the effect of dry strength agent on improving bonding potential of recycled OCC fiber could be confirmed. As an appropriate addition level of amphoteric PAM, below 1% based on dry pulp weight was suggested. Different from virgin UKP, density of recycled test liner can be increased by the blending of OCC fines and strength properties also can be improved. However, excessive blending of OCC fines could result in decreasing of density and serious weakening of test liner. The best blending ration of fines in test liner can be determined as about 30%. Taking into account the fines content in general OCC pulp as 50%, excessive 20% of fines were supposed to be fractionated and removed in order to achieve the best strength of Condebelt press dried test liner.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.3
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• pp.51-56
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• 2016

The most widely used glue in a corrugator is starch, which is a natural polymer. This material needs thermal energy to achieve a binding force, so a heating section is installed in a corrugator. However, this heating section can cause quality problems in linerboards and corrugating medium and increase the production cost because of the high cost of fossil resources. Therefore, a new adhesive that provides the binding force at lower temperatures than the conventional one must be developed. In this study, SB-latex was selected as a co-adhesive and added to the starch solution. The addition of the SB-latex was determined based on the viscosity of the new adhesive. The adhesive strength and the drying energy reduction of a corrugated board were measured to evaluate the functionalities of the new adhesive. The addition of SB-latex was determined to be under 20% of the oven-dried starch based on the viscosity of the new adhesive. The adhesive strength was improved and the drying energy was reduced by applying the new adhesive.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.5
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• pp.17-26
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• 2011

Drying behavior and physical properties of HwBKP, SwBKP, and OCC handsheets depending on kneading, refining and wet pressing were analyzed. The maximum drying shrinkage velocity was newly adopted to verify the effect of mechanical treatment of pulps by evaluating drying behavior according to varying the kneading, refining and wet pressing treatments. Those various treatments were changed to evaluate the relationship between the maximum drying shrinkage velocity and handsheets properties. When the drying shrinkage and the maximum drying velocity increased by refining and wet-pressing, handsheets strength was increased. The maximum drying shrinkage velocity showed higher correlation with physical properties of paper than WRV at different refining loads at SwBKP and mixed pulp. At high wet-web dryness, drying shrinkage, the maximum drying shrinkage velocity and strength properties of handsheet were increased. It meant that drying shrinkage behavior was highly affected by not only fibers' shrinkage but also fiber bonding. Kneading pre-treatment for KOCC and SwBKP effectively modified fiber properties and increasing paper strength and drying shrinkage. The effect of kneading pre-treatment was also confirmed by the maximum drying shrinkage velocity. Strength properties of mixed pulp handsheets were not increased by the kneading pre-treatment, although the maximum drying shrinkage velocity and WRV was increased. It meant that fibers network bonding of HwBKP was limited because of ves sels and ray cells' interference for bonding. Therefore in order to improve paper strengths containing HwBKP by mechanical treatments, interference of vessels and ray cells for fiber bondings should be carefully controlled.

• Korean Journal of Microbiology
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• v.47 no.1
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• pp.50-55
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• 2011

A simple and rapid method was developed for monitoring of Gram-positive bacteria in the wastewater treatment system. Culture suspensions of 4 Gram-positive and 4 Gram-negative strains were filtrated and stained with a polyethersulfone membrane filter and Toluidine Blue-O. To establish quantitative color image analysis, the intensity value of RGB (red-green-blue) color of a scanned filter image was analyzed with a photographic program. Red and green color values of Gram-positive bacteria were higher than those of Gram-negative bacteria. This method was applied to the activated sludge mixed with the Gram-positive bacteria. Although evaluation was difficult due to the irregular size and shape of flocs, the population of Gram-positive bacteria in the activated sludge could be monitored with floc dispersion technique. The more amounts of Gram-positive bacteria in the activated sludge led to the increase of red and green color values. This method provides a rapid and quantitative measurement of Gram-positive bacteria within the wastewater treatment systems.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.14-14
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• 2012

Nylon 6 섬유는 우수한 기계적 물성과(강성, 탄성회복률 등) 염색성 등의 장점을 가지고 있어 의류용 등의 다양한 용도로 활용되어 왔다. Nylon 6 섬유를 포함한 대부분의 합성섬유는 천연섬유인 cotton 대비 흡수성이 낮고, cotton은 흡수성은 탁월하나 수분 건조속도가 매우 느리고 가격이 고가(약 10$/kg)여서 이를 대체할 새로운 고쾌적성 의류용 nylon 합성섬유의 개발이 시도되고 있다. 1953년 최초로 합성이 보고된 nylon 4는 구조상 소수성 탄소수가 적으며 친수성 아마이드기가 상대적으로 많아 흡수성과 속건성이 탁월한 이점을 가짐으로써 면을 대체할 수 있는 꿈의 합성섬유로 인식되었다. 1980년대 Chevron Research사를 중심으로 활발한 사업화 연구가 진행되었지만, 녹는점 $265^{\circ}C$) 대비 낮은 열분해온도($260^{\circ}C$) 특성으로 방사가공 시 내열성 문제를 극복하지 못해 아직까지 상업화에 이르지는 못하고 있다. 최근, 일본 산업기술종합연구소(AIST)를 중심으로 다시 바이오매스 유래 nylon 4의 개발이 시도됨에 따라 의류용 용도전개에 있어 가격 경쟁력을 갖춘 획기적인 소재 전환이 기대되고 있으며, 이로 인해 nylon 4 중합 연구가 다시 전 세계적 주목을 받기 시작하였다. 국내에서도 최근 nylon 4의 방사 내열성을 극복하고 기능성 부여가 가능한 nylon 4 공중합물에 대한 대체 연구가 본격적으로 진행 중에 있다. 본 연구에서는 현재 국내에서 진행 중인 nylon 4 공중합 섬유의 연구동향과 함께 nylon 6 대비 물성 및 염색특성 차이를 비교함으로써 향후 산업화에 기초 자료로 활용하고자 한다.

• Current Research on Agriculture and Life Sciences
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• v.31 no.2
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• pp.124-130
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• 2013

The significance of environment change and genetic safety has been recently recognized by many genetically modified (GM) plants. This study was to evaluate the safety of drought-tolerant rice and to identify the environment variance. The GM rice of drought-tolerant rice and four check cultivars were analyzed the data on agronomic characters and principal component in large-GM crop field. There was no significant difference in agronomic characters between the drought-tolerant rice and donor plant, 'Ilmi'. Grain yield showed the standard deviation of the difference, did not significant statistically. Related to grain characters, grain appearance were similar to the drought-tolerant rice and donor plant, 'Ilmi'. In Chemical characters, brown rice of the drought-tolerant rice and a donor plant, 'Ilmi' did difference in starch and protein, however, was similar as 'Ilpum'. These results indicated that drought-tolerant rice may perform to detect genetic safety in GM plants progeny.