• Journal of Korean Society of Environmental Engineers
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• v.28 no.3
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• pp.292-299
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• 2006

Batch experiments were performed to evaluate the effects of the electron donor dosage and the initial biomass on the reductive dechlorination of perchloroethene(PCE) with benzoate as an electron donor. When benzoate was added less than the theoretical requirement for dechlorination(electron donor/acceptor ratio=0.5 and 1), the dechlorination efficiency increased from 71% to 94.3% with the increase in benzoate dosage, but the fraction of electron equivalent utilized for dechlorination decreased from 92.7% to 79.6%. Methane production was observed when the hydrogen concentration was higher than the threshold value(10 nM) after PCE and trichloroethene (TCE) were reduced to cis-1,2-dichloroethene(cDCE). When benzoate was added more than the theoretical requirement, the residual hydrogen converted into methane after the completion of dechlorination. The increase in the seeding biomass shortened the lag time for dechlorination, but it did not affect the maximum dechlorination rate as it was mainly governed by the benzoate fermentation rate. When the seeding biomass concentration was high, active dechlorination during the early period increased dechlorination efficiency while decreasing methane production.

• Journal of Korean Society of Steel Construction
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• v.18 no.3
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• pp.361-371
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• 2006

In recent years, to overcome drawbacks related to the aplicati on of classical structural optimization algorithms, various drift design methods based on factores of member displacement participation factors have been developed to size members if they satisfy stiffness criteria. In particular, a resizing algorithm based on dynamic displacement participation factors from the response spectrum analysis has been applied in the drift design of steel structures subjec ted to seismic lateral forces. In this aproach, active members are selected for displacement control based on the displacement participation fa ve members may be taken out and added to the active members for the drift control. The resizing algorithm can be practically and effectively applied to drift design of high-rise buildings however, the inelastic behavior o f the resizing algorithm has not ben evaluated yet. To develop the resizing algorithm considering the performance of nonlinearity as well a s elastic stifness, the evaluation model of resizing algorithm s is developed and aplied to the examples of moment-resisting steel frame, which is one of the simplest structural systems. The inelastic behavior of moment-resisting steel frame designed by the resizing algorithm is also discussed.

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.537-543
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• 2014

As environmental matters such as Green House Effect rise, many construction industries are putting an effort on minimizing environmental impact in terms of building life cycle throughout the world. However, in South Korea, evaluating the eco-friendly building based on life cycle assessment has been facing an academic ostracism while the most studies are focusing on assessing the 6 environmental impact assessments of passive apartment based on life cycle assessment. The theoretical consideration of the life cycle assessment and environmental impact category were performed and the direction of the study was set up. Also, existing apartment and passive apartment, which had same structure and same type were chosen and building materials per unit area were compared to find out the difference environmental impact for building life cycle. As a result, passive apartment was rated as low level among the 6 environmental impacts. Also, effect of building material on passive apartment was more important than its operational stage.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.119-119
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• 2015

스마트워터그리드의 목적은 기존 용수부족 문제의 근본적인 해결을 위해 새로운 취수원을 개발하고, 지역 내의 수자원을 효율적으로 활용하는 방안을 강구하는 시스템을 구축하는데 있다. 따라서 운영비용을 최소화하면서 수요처에 적정한 수량과 수질의 용수를 공급할 수 있도록 해야한다. 스마트워터그리드 구축 시 설비 비용에 대한 부담으로 보급 확산에 어려움을 겪을 가능성이 높으므로, 비용 효과적(Cost-effective)인 측면에서 스마트워터그리드의 경제성을 검토할 필요성이 있다. 본 연구에서는 자료의 한계로 인해 기존의 다중수원에 대한 경제성분석 사례를 인용하여 상수도 생산원가 절감액, 댐 건설과 관련된 비용의 감소, 물 오염 감소 등으로 편익을 간접적으로 계산하고, 기술적으로 물량이 충분하다는 가정하에 다중수원들간의 비용효과분석 수행하였다. 분석결과, 현재 공급하고 있는 상수도 시스템이 다른 다중취수원에 비해 비용효과적 우위에 있는 것으로 나타났다. 지하수, 해수담수화 등 새로운 수원을 찾는 노력이 필요하며 지하수는 가장 쉽게 활용할 수 있는 대체 수원이지만, 관정개발에 많은 비용이 들고 대량으로 수원을 공급하기 어렵다는 단점이 있다. 해수담수화는 대체수자원으로서 중요성이 더욱 강조될 것으로 보이지만, 시설의 설치 및 운영에 드는 높은 비용과 함께 육지에서 물을 대량으로 연안에서 멀리 떨어져 있거나 고도가 높은 지역은 해수담수화 기술의 적용이 어려울 것으로 여겨진다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.72-84
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• 1993

This study was carried out to understand the varietal variation in physicochemical properties of rice grain and those environmental changes by different transplanting time, and to elucidate the interrelationships among the factors related with eating quality of cooked rice. Fifty three rice samples, among which fifty samples were harvested at ordinary or late transplanted plots of the Crop Experiment Station in Suwon and three samples were harvested orpurchased from Niigata prefecture in Japan, were tested for various physicochemical components of rice grain and some physical factors of cooked rice. All of twenty seven rice cultivars tested were the recent-bred Korean japonica rice showing the wide range of maturity from early to medium-late heading and considerable difference in palatability of cooked rice. Amylose content, taste value by Nireco palatability tester (TVN), iodine blue color of cooking extracts(IB), and the ratio of IB /extracted solid amounts (ES) increased significantly by late transplanting, while viscosity (VN) and Mg / K. N value by Nireco tester, hot-water absorption of milled rice (HA), loss tangent of cooked rice by Rheolograph-Micro(LT), and most viscogram characteristics except setback viscosity (C-P) decreased drastically by late transplanting as compared with ordinary transplanting. Most of physicochemical properties of milled rice revealed narrower varietal variation in lately transplanted plot than in ordinary transplanted one. Protein content (PRO), volume expansion rate of cooked rice(VE), C-P and all physical factors of cooked rice by Rheolograph-Micro showed almost negligible seasonal variation, while amylose content (AM), VN, HA, IB/ES, peak viscosity(P), hot viscosity(H) and breakdown(P-H) viscosity exhibited considerably large seasonal variation. The early-headed varieties revealed lower amylose content and smaller seasonal variation of IB/ES compared with medium or medium-late headed rice varieties. AM was closely associatied with IB and IB / ES and VN was highly correlated with Mg/K. N and TVN in both ordinary and late transplanted plots. VN also was highly negatively correlated with cooking characteristics and highly positively correlated with viscogram properties in ordinary culture. PRO was closely connected with moisture content of milled rice and L T in ordinary transplanted plot. IB, which was closely connected with ES, was also singificantly associated LT, P and P-H in ordinary seasonal culture. IB/ES was highly negatively correlated with P, P-Hand P-H / C-P in ordinary culture but with LT and dynamic viscosity of cooked rice in late seasonal culture. The thirty rice cultivars were largely classified into two varietal groups by cluster analysis with physicochemical properties related with eating quality of cooked rice. Korean and Japanese high-quality rice cultivars were separately distributed in two respective varietal group.

• Korean Journal of Weed Science
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• v.18 no.4
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• pp.304-313
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• 1998

Foliar retention of pyribenzoxim (1% EC) was measured using the fluorescent dye rhodamine B, and related to efficacy and phytotoxicity to barnyardgarss (Echinochloa crusgalli) and rice (Oryza sativa cv. Chucheong), respectively. Effects of nozzle types (8002E flat-fan and disk-type), addition of adjuvant, variation of herbicide concentration or spray volume were compared. In barnyardgrass, foliar retention of pyribenzoxim at a recommended condition (application rate : 30g ai/ha, spray volume : 1000 L/ha) was 2.3 to 2.7 or 1.4 to $1.5{\mu}g$ ai/g fresh foliage when sprayed using the disk-type nozzle with or without adjuvant, respectively, and 0.6 to 0.7 or 0.3 to $0.5{\mu}g$ ai/g fresh foliage when sprayed using the flat-fan nozzle with or without adjuvant, respectively. The slope of increase in foliar retention was 1.0 to 1.8 when application rates increased from 10 to 60g ai/ha at 1000 L/ha, while that was 1.6 to 2.4 when spray volume increased from 330 to 2000 L/ha at $30{\mu}g$ ai/L concentration. Foliar retention of pyribenzoxim had a close relationship with herbicidal activity; regardless of spray conditions, retention to provide 90% control was about $0.8{\mu}g$ ai/g fresh foliage, and below this retention amount, efficacy decreased almost linearly. In rice, foliar retention at the recommended condition was 1.9 to 2.3 or 1.2 to $1.3{\mu}g$ ai/g fresh foliage when sprayed using the disk-type nozzle with or without adjuvant, respectively, and 0.6 to 0.9 or $0.3{\mu}g$ ai/g fresh foliage when sprayed using the flat-fan nozzle with or without adjuvant, respectively. The slope of increase in foliar retention was 1.0 to 2.8 when application rates increased from 30 to 120g ai/ha at 1000 L/ha, while that was 1.3 to 4.4 when spray volume increased from 1000 to 4000 L/ha at $30{\mu}g$ ai/L concentration. Despite the great difference in retention, rice phytotoxicity was not observed in any of these spray conditions, suggesting retention differences within 4-fold increase of application rate or spray volume do not affect rice safety. When pyribenzoxim 1EC was sprayed in tank-mix with several other commercial pesticide formulations, its retention to rice foliage tended to increase by 30 to 50%.

• Electronics and Telecommunications Trends
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• v.28 no.4
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• pp.53-63
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• 2013

전세계적으로 우편 물량의 감소, 민간 사업자와의 경쟁심화 등의 환경 변화 속에서 안정적 우편수익을 창출하고 소포우편물의 소통품질을 향상하기 위해 주요국 우편사업자들은 단시간에 우편물 처리를 자동으로 구분하여 자동 처리율을 극대화하기 위한 방안을 모색하고 있다. 국내 우정사업본부도 신규 도입 및 교체 시기가 도래함에 따라 중장기적 관점의 신규 소포구분기의 도입계획 수립하였다. 그 일환으로 소포구분기의 표준 규격을 마련하고 소포구분기의 국산화에 박차를 가하여 향후 도입 비용 및 유지보수 비용을 절감하기 위해 노력하고 있다. 세부적으로 국내 PLC(Programmable Logic Controller) 및 제어 장비를 통해 제어 기술을 확보하고 표준화된 운영이 가능토록 현존 소프트웨어 시스템의 고도화를 통해 소통품질 및 업무성과 개선 기술을 실제 현장 운영을 통해 개발 검증 중이다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.131-136
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• 2003

쌀은 우리 국민의 주식이자 단일 작물로써 재배면적이 가장 많은 105-110만㏊ 수준에 연간 생산량도 500만톤 이상을 꾸준히 유지하고 있는 중요한 식량작물이자 농가의 주 소득원이다. 그러나 이렇게 쌀의 생산량은 꾸준한데 비해 국민의 식생활이 점차 인스턴트 화되고 육류소비가 증가하면서 연간 쌀 소비량이 1990년 119.6kg에서 2002년 87.0kg으로 급격히 감소추세를 보임으로써 2002년도 기준으로 약 1,190만석의 재고가 발생하고 있다. 더욱이 WTO출범이후 MMA 물량이 2002년 125만석에 이르렀고, 2005년 이후 더욱 증가 할 것으로 예상되고 있어 국내 쌀 시장은 이제 과잉공급시대에 직면하고 있다. (중략)

• Tribology and Lubricants
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• v.3 no.2
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• pp.15-22
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• 1987

윤활유는 일반적으로 윤활기유의 물성을 개량하기 위해 여러종류의 윤활유 첨가제를 포함하고 있는데 이 첨가제는 윤활기유가 가지고 있는 물성을 강화시키기 위해 첨가하는 것과 윤활기유에는 없는 물성을 얻기 위해 첨가하는 두가지로 나눌수 있다. 윤활기유의 산화분해, 열분해, 마찰이나 마모의 감소등을 위해 첨가흔 넉승 전자에 속하는 경우이고 기유 분해분의 침적을 막아주거나 부식을 방지하며 온도에 따른 점도변화를 극소화시키기 위한 첨가제는 후자에 해당한다. 즉 윤활유 첨가제는 윤활기유의 물리적, 화학적 성질을 보완 또는 강화시키므로서 윤활유로서의 소기의 목적을 달성하도록 첨가하는 화학물질을 말한다. 본 보에서는 위에서 열거한 여러종류의 첨가제 중 사용물량이 많아 수입대체 효과가 뚜렷한 6종의 첨가제의 국산화에 대한 연구결과를 간략하게 기술하였으며 앞으로 2회에 걸쳐 나누어 설명코자 한다.

• Electronics and Telecommunications Trends
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• v.25 no.4
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• pp.83-92
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• 2010

인터넷과 모바일의 활성화로 지속적으로 우편물량이 감소하고 있는 현 상황에서 우편 사업자들은 새로운 수요를 창출하고자 많은 노력을 하고 있다. 신규 시장을 만들기 위한 노력의 일환으로 고객의 주소를 보유하고 있는 선진 해외 우정사업자들은 상품 또는 서비스의 판매를 위한 기업의 전통적인 마케팅 방법인 Direct Mail(DM)에 지리정보(GIS) 기반의 고객관리기법(gCRM)을 접목한 홍보우편 서비스를 도입하고 있다. 본 고에서는 홍보우편을 위한 one-stop 서비스를 제공하고 있는 미국, 캐나다, 독일의 홍보우편 서비스 동향을 살펴보고, 국내 우정사업에 적용하고자 하는 홍보우편 마케팅 기법과 고객주소, GIS, gCRM 등이 결합된 홍보우편 서비스 시스템을 위한 요소기술들을 살펴보고자 한다.