• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.285-288
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• 2004

자유수산기는 단분자 제조공정으로 분자, 원자 충에서 가공되어 기타 활성입자와 함께 얻어지며, 20% 이상의 고 밀도 질량비는 양산공정에 중요한 의미를 부여한다. 자유수산기가 선박안정수의 외래침입생물과 적조처리 및 양식수체 정화에도 효과적인 새로운 처리기술로 선박 안정수에 포함되어 타 지역으로부터 옮겨지는 외래침입생물 처리 방안의 하나로, 강 전리방전 기술을 적용하여 고 밀집산소와 물분자로부터 고농도 수산자유기(OH: hydroxyl radical)를 전리, 발생시켜서 활성입자를 신속히 확산시켜 비교적 낮은 수산기농도 하에서 유해성침입생물을 사멸 처리하는 환경 친화적 녹색 청정처리방법을 제안하였다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.37-37
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• 2011

열가소성 고분자 물질인 PET[poly(ethylene terephthalate)]는 섬유 및 필름, 음료병 등에 널리 사용되는 대표적인 범용 소재이며, 전체 PET 제조업은 2013년 약 200억불에 달할 것으로 예상되는 큰 시장이다. 최근 급격한 산업화에 따른 전 세계적인 환경오염의 심각성이 부각되면서 기업들의 환경 친화적인 제조 활동 및 생산 프로세스의 개선이 요구되고 있다. 현재 폴리에스테르 수지를 제조하기 위해 국내외 업체에서 가장 널리 사용 되고 있는 중합촉매는 중금속 원소인 고순도 삼산화안티몬($Sb_2O_3$)이며 통상 중합공정 중에 150~300ppm의 촉매가 사용된다. 세계보건기구(WHO)의 국제암연구기관(IARC)에서는 안티몬을 인체 발암성이 있는 물질로 분류 하여 현재 유럽을 중심으로 안티몬 사용을 제한하는 환경 규제가 가속화 되고 있다. 폴리에스테르 수지 제조 공정중 안티몬 촉매를 사용할 경우 정련, 염색, 알칼리 감량시 중금속(안티몬)검출에 따른 수질 오염 및 폐수처리비용이 증가하게 되며 대량의 중합촉매 사용에 따른 이물 증가로 작업성 및 품질 문제가 상존하게 된다. 따라서 이러한 제조 공정중의 고위험성 물질을 대체할 친환경, 고부가가치 신규 무독성 PET 소재 및 제품이 각광을 받게 될 것이다. 이번 연구에서는 티타늄계(Ti-based) 무독성 촉매를 이용하여 PET 중합을 실시한 Sb-free PET원단의 염색특성을 알아보는 것으로 분산염료 3종 (Red, Yellow, Blue)으로 염색이 완료된 원단을 spectrophotometer 를 이용하여 L, a b값과 K/S값으로 측정하였다. 동일한 염색 조건을 위해 두 종류의 원단을 하나의 실린더에서 기존 PET 염색과 동일한 조건으로 염색을 실시하였으며 실험 결과 전반적으로 기존 PET와 유사한 염색 특성을 보였다. 염색견뢰도 평가에서도 Sb-free PET원단과 기존 PET원단의 세탁 견뢰도, 마찰 견뢰도, 일광 견뢰도를 비교 했을 시 두 원단 모두 4~5급으로 우수한 견뢰도를 나타내었다.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.55-62
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• 2005

This study was conducted to evaluate the application of a bio-composite made by the addition recycled fiber board flour as filler. Recycled fiber board (high density fiber board, HDF) flour was added to polyolefin polymer low density polyethylene (LDPE) and polypropylene (PP) for the preparation of bio-composite materials. The mechanical properties and processability of the recycled HDF flour filled LDPE and recycled HDF flour filled PP bio-composites were then measured and compared to those of wood flour (WF) and rice-husk flour (RHF) filled LDPE and PP bio-composites, respectively. The tensile and impact strengths of the recycled HDF flour filled LDPE and PP bio-composites had similar mechanical properties to those of the WF and RHF filled LDPE and PP bio-composites. To measure the processability, torques of the bio-composites were also measured. The torques of the HDF flour filled LDPE and PP bio-composites were lower than those of the WF and RHF filled polyolefin (PP and LDPE) bio-composites with a filler loading of 30 wt.%. This result showed definite processability, which was not related with the distribution of the particle size of the material added. The recycled fiber board flour filled bio-composites showed applicability as substitutes for the bio-composites currently used in the bio-composites industry.

• Journal of Digital Convergence
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• v.11 no.2
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• pp.249-256
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• 2013

Recent days, the global warming problem due to excessive use of fossil fuels has been the world wide issue so that Korea government and developed countries make an alternative plan for eco-friendly and transportations by utilizing bicycles for health promotion. Existing Public Bicycle Rental Service Systems provide simple service such as bicycle rental management and tracking the location. However there is no user-side service for the information of the measure of carbon reduction, or use of bicycles. The proposed system in this paper provides users' health information, environmental information, personal information, counseling services and the measures of carbon reduction. The new system has been developed to carry out reducing carbon and growing green in terms of using bicycles by adopting Web 2.0 technology.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06c
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• pp.53-58
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• 2007

선진각국에서 고령화 문제를 해결하기 위하여 고령친화 산업과 관련된 많은 연구들이 진행되고 있다. 본 논문에서는 노인 요양 또는 복지 시설내 노인들의 거주 환경 변화 및 거주자의 활동 양상을 측정하는 노인케어 유비쿼터스 시스템 knu-SCS(KangNam Ubiquitous Senior Care System)에 대하여 연구하였다. knu-SCS 시스템은 조도, 습도, 온도 센서, 웹 카메라 등으로 구성되며, 각종 센서들이 감지한 데이터를 저장, 가공, 분석하기 위하여 데이터베이스를 설계 및 구현하였다. 또한, 데이터베이스에 저장된 데이터들을 사용자들에게 시각적으로 제시하기 위하여 센서 웹을 구현하였다. 센서 웹에서 제시하는 데이터들은 일상적인 노인 행동 및 생활환경을 인지할 수 있는 자료가 되므로, 이를 기초로 노인들이 겪을 수 있는 건강상 문제나 일상생활의 불편함을 해소하는 등 노인 케어에 활용될 수 있다.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.10
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• pp.221-226
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• 2002

As environmental restriction has continuously become more strict, machining technology has emphasized on development of environment-friendly technologies. In cutting technology, it has been well recognized that cutting fluids might have undesirable effects on workers health and working environment and, hence, recently there have been numerous attempts to minimize harmful effects of cutting fluids on environments. To minimize the use of cutting fluids in machining, conventional cutting fluids have been replaced with the technologies of pressurized cold air and minimum quantity lubrication (MQL). Compared with milling, turning is continuous cutting process, where tools are continuously heated up and lack of lubricity could lead to tool wear and deteriorated surface roughness. In this work, it has been investigated how tool wear and surface roughness could be affected by cutting conditions, supply and cooling methods. The experimental results show that MQL technology is able to minimize conventional cutting fluids.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.6
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• pp.40-45
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• 2016

It should be noted that the use of the lathe scrap for making fiber reinforced cementitious composites raised friendly environmental effect as well as economy because the lathe scrap is a by-product of steel manefactures and is occurred when lathe and milling works of them are conducted to process steel manufactures. Thus, the purpose of this experimental research is to investigate workability and strength characteristics of lathe scrap reinforced cementitious composites(LSRCCs). For this purpose, three types of lathe scraps were collected from processing plants of metal, and then LSRCCs containing these were made for 2mm width and 40mm length. As a result, it was observed from the test results that the workability of LSRCCs was slightly decreased than plain mortar and the flexural strength of LSRCCs were much larger than these of plain mortar and effect of types of lathe scrap on the characteristics of LSRCCs were somewhat large.

• Polymer(Korea)
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• v.32 no.5
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• pp.478-482
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• 2008

The effect of 1,3-dioxolane on the structural development in the optical polycarbonate film was studied. The 1,3-dioxolane was used as an environmental friendly solvent for manufacturing solution-cast polycarbonate film instead of methylene chloride. The evaporation rate in film drying process decreased due to the high boiling temperature of 1,3-dioxolane. This caused the crystallization in the polycarbonate film. As a result, The increase of crystallinity and roughness led to the decrease of light transmissivity. It was also found that the lowering of mechanical properties in polycarbonate film was attributed to the morphological change due to the solvent evaporation rate in film drying process.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.6
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• pp.114-120
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• 2001

It is necessary to develop a new metal cutting technology which does not use cutting fluid, since cutting fluid can have undesirable effect on workers's health and working environment. For this to be possible, it is necessary to replace the conventional method of using cutting fluid, whose basic functions are removing chip and heat, and providing lubrication between tool and chip. In this work, cooled air is utilized in order to replace cutting fluid. Experiments were carried out while cutting workpiece with HSS flat endmill under a variety of supply conditions for cooled air. Also the performance characteristics of the air cooling system. which was built for the experiments, were carefully analyzed. For the reliable operation of air cooling system. moisture contained in the cooled air had to be removed before being supplied to the workpiece and tools. It was found that depending on the amount of its flow rate the temperature of cooled air changes at the time of injection from the nozzle. The flow rate of cooled air also plays an important role in removing the accumulated chip on the workpiece. After comparing the flank wear for the three cases of using cooled air, cutting fluid, and pure dry technique, it was demonstrated that the level of flank wear was similar for the cases of cooled air and cutting fluid. The pure dry technique, however, showed higher level of flank wear than cooled air.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.12
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• pp.1672-1681
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• 2007

Cationization is effective to complement the defects of Tencel blended fabrics by introducing new functions. For this purpose, we used chitosan, which is congenial to the human body, free of pollution, and easily reacted. Then, we compared it to the Tencel single fabrics. To perform such effective cationization, the fabrics were treated with chitosan after NaOH pretreatment and enzyme treatment thereof. After that, the fabrics were treated with a crosslinking agent and a softner. The dyeing property of the cationized Tencel blended fabrics and reactive dye, which is a type of anionic dye, show a high concentration in neutral salt and excellent repulsive power between the fabrics and the decreased dyes. The dyeing property of the chitosan treated fabrics represented better performances than that of untreated fabric in the lower concentration of neutral salt. Meanwhile, when it was dyed with certain acid dyes, the dyeing property of the chitosan treated fabrics showed better results due to the reaction of an amine group, which was introduced by chitosan treatment. Thus, the verification of the cationization of the Tencel blended fabrics was performed. The washing fastness of the Tencel blended fabrics showed a little bit better than that of the Tencel single fabric, and it represented a better performance in the dye with a reactive dye than that of an acid dye.