• Bulletin of the Society of Naval Architects of Korea
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• v.41 no.1
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• pp.24-32
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• 2004

중소형조선업은 선박의 역사와 궤를 같이 하는 조선산업의 뿌리이다. 이러한 중소조선업은 산업혁명을 기점으로 증기기관이 출현하고 뒤이어 제강, 용접기술 등의 기술이 발전함에 따라 선박의 규모가 점차로 대형화하고, 또한 자본주의의 성장과 국제무역이 증가함에 따라 신조 선박건조가 세계 단일의 시장으로 형성되면서 대형조선업과 나누어지게 되어 이전과는 다른 별개의 의미를 가지게 되었다. 오늘날 중소조선업이라 함은 일의적으로 정의할 수는 없으나 내수시장을 중심으로 국민의 생명과 재산, 생업과 삶의 질 등과 직결되는 선박을 건조하는 산업으로 대변할 수 있다. 한편, 막강한 자본력을 배경으로 한 대형선박과 대형조선소의 출현은 중소조선 기술인력의 대기업 이동과 함께 중소조선업은 설비낙후와 기술 경쟁력 상실로 쇠퇴일로를 걷게 되었다.(중략)

• Journal of Korea Ship Safrty Technology Authority
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• s.32
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• pp.2-11
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• 2012

강화플라스틱(FRP)이 가진 저비용 장점에 비하여 화재 및 환경오염 문제가 대두됨에 따라서 알루미늄 소형 선박에 대한 수요가 증가하고 있다. 알루미늄 재질의 선박 건조에도 절단, 성형, 용접 및 조립의 과정이 필요하지만, 소형 선박에는 박판이 사용되기 때문에 일반 강선과는 다른 공법 및 가공 조립법이 사용된다. 본 기사는 알루미늄 재료의 절단 공법, 용접 공법의 현황과 미래 기술 방향을 정리하였다. 또한 성형 공정의 문제점과 이를 위한 개선 방안을 제시함으로써 알루미늄 선박의 건조 생산성 향상 및 정도 관리의 편의성을 위한 방안을 모색하고자 한다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.209-210
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• 2021

This study aims to develop ultra-low-shrinkage high-quality concrete. Therefore, the concrete drying shrinkage characteristics according to the type and amount of the shrinkage reducing agent were reviewed. As a result, the performance of Hexylene Glycol(HG) and Polyol was superior to that of PolyEthylene Glycol(PEG), which is most widely used in Korea. In addition, the shrinkage reduction effect was improved as the amount of PEG was increased, but the disadvantage of the strength reduction when excessive use was confirmed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.377-378
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• 2023

This study examined the effect of curing conditions on the compressive strength of dry mortar for floor. The compressive strength according to the relative humidity during curing was compared, and the influence of expansive additives on compressive strength under water curing was reviewed. As a result, low relative humidity conditions during curing was not effective in improving the compressive strength of dry mortar for floor, and it was judged that the continuous hydration reaction insufficient due to lack of the moisture supply. In order to improve compressive strength, high relative humidity maintenance was found to be an important factor. However, under water curing conditions, the compressive strength has decreased as a result of continuous volume expansion due to the use of the expansive additives.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.198-203
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• 2006

This study was conducted to select the temperature for hot air drying method, cutting method, and solution that inhibits enzymatic browning in making high quality powder from sweetpotato roots. It was observed that $70^{\circ}C$ was the best temperature for air drying method wherein the dry matter rating, dry matter time, flour yield and chemical component were considered. The proper cutting thickness should be 2.0 mm considering the vitamin C content and sensory evaluation of sweetpotato flour. Also, 1% vitamin C solution inhibited enzymatic browning of sweetpotato.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1154-1161
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• 2006

Air drying equipment was built as a device for reduction of dewatered cake from wastewater and waterworks sludge and to reproduce it by reusable matter. Dewatered cake was supplied into the air drying equipment which operated by air velocity of 80 m/sec, air rate 30 $m^3/min$ and air temperature of $40^{\circ}C$, and dried to produce the dried powder. The air drying equipment was composed of the air ejector which made high-speed fluid field, and cyclone which made circling fluid field. Dewatered cake was crushed at the high-speed zone as first step, and formed into dried powder of sphere shape by the collision between particles at the circling fluid zone.. Wastewater sludge with water content of 82.5 wt% was supplied 1.0 kg/min into air drying equipment and produced the dried powder which had the water content of 62.3 wt% and mass median diameter of 2.4 mm after process. At that time, it was analyzed that water removal rate was 0.1 $H_2O{\Delta}kg/min{\cdot}DS$ kg and air consumption was 170 $m^3/DS$ kg. Under same experimental conditions, when waterworks sludge was dried, water content of dried powder decrease to 47.5 wt% and mass median diameter decrease 2.1 mm and water removal rate increase 0.13 $H_2O{\Delta}kg/min{\cdot}DS$ kg. Air consumption increase 180 $m^3/DS$ kg with comparison to the results of wastewater sludge. Therefore, this technology was evaluated that drying the dewatered cake of waterworks sludge was more efficient than wastewater sludge, and also economical sludge handling technology due to drying the cake by only air.

• 농업기술회보
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• v.49 no.5
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• pp.34-35
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• 2012

벼 이삭이 팰 때는 각종 환경에 민감한 시기로 물 관리 등 벼농사 후기관리를 잘해야 최고품질의 쌀을 생산할 수 있다. 유숙기 이후 물 관리와 적기수확 시기, 벼를 수확한 이후 올바른 건조과정을 통해 최고 품질의 쌀을 생산하는 기술을 알아본다.

• 농업기술회보
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• v.46 no.5
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• pp.34-35
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• 2009

쌀의 품질을 높이기 위해서는 고품질품종 선택, 재배방법 등 여러 가지 기술이 필요하지만, 후기 물 관리와 알맞은 수확시기에 수확하여 적절한 온도에 말리고 저장하는 기술 또한 매우 중요하다. 수확기를 앞두고 벼의 적기수확과 건조 저장 등 수확 후 관리요령에 대하여 알아보고자 한다.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.06a
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• pp.51-51
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• 2020

• 지반과기술
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• v.3 no.1
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• pp.57-66
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• 2006