• The Journal of Natural Sciences
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• v.5 no.1
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• pp.15-28
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• 1992

토양에 20년간 3요소+생고를 처리하였을때 토양의 화학적 성분, 공극율, 입단구조가 잘 발달되었다. 또한 이 처리에 의하여 CGR은 영화분화기때 가장 높았으나 무처리구나 3요소단용구에서는 전생육기간을 통하여 계속 증가하는 경향을 띈 반면 3요소+생고처리구에서는 영화분화기이후 계속 감소 하는 추세을 나타내고 있다. 현미수량에 있어서는 3요소+생고처리에 의하여 11%의 증가효과가 있었으며 이것은 주로 이삭의 일.이차기경의 분화수가 증가하였기 때문이었다. 또한 미립형태에 있어서도 완전미의 비율이 높았는데 이것은 등숙속도와 매우 밀접한 관계가 있어서 등숙속도가 빠를수록 심백미, 복백미 및 동할미가 많았다. 3요소 + 생고속도는 40DAH이었다.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.819-821
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• 2003

본 논문에서는 압전 트랜스듀서의 임피던스 해석을 유한 요소법을 통해 실험적으로 검증하였고, 이러한 유한 요소법을 이용하여 압전 변압기의 동작 주파수 및 등가회로 정수를 도출하였다. 또한, 등가 회로법을 이용하여 부하 변동에 따른 압전 변압기의 공진 주파수와 효율 변화를 분석하고 이를 실험적으로 검증하였다. 한편, 유한 요소법과 자동 요소 분할 프로그램(Auto-Mesh Generator), 최적화 알고리즘을 이용하여 일정 부하에서 최대 효율을 갖는 압전 변압기의 형상 최적화를 수행하였는데, 최적화 기법으로는 sinc 함수의 수렴 결과를 통해 타당성이 입증된 진화 알고리즘 (Evolution Strategy)을 적용하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.99-107
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• 1997

The effect of easily decomposable organic carbon (methanol) application on the behavior of nitrogen derived from surface-applied urea in submerged soil was investigated. Two rates of urea (150 & $300kg-N\;ha^{-1}$) and three levels of methanol (2, 4, 8 ml) were applied to 10 g soil samples. The samples were incubated for 30 days under submerged conditions. The flood water and the soil were sampled for analysis of urea-N, $NH_4-N$ and $NO_3-N$ every 10 days. Urea-N in flood water and in soil at the rate of $150kg-N\;ha^{-1}$ and that in flood water at the rate of $300kg-N\;ha^{-1}$ were not detected but the urea-N concentration in soil at the rate of $300kg-N\;ha^{-1}$ with 8 ml methanol treatment was 4.7 on the 10th day from incubation. $NH_4-N$ concentrations in flood water and in soil increased with increasing urea application rates whereas they decreased with increasing methanol treatment. $NO_3-N$ concentration in flood water and in soil were similar regardless of the urea and methanol application rates. The total amount of $NH_4-N$ in flood water and in soil decreased with increasing methanol treatment, 0 ml & 2 ml, whereas the total amounts of $NO_3-N$ in both flood water and soil increased slightly at higher rates of methanol treatment, 4 ml & 8 ml. The total amount of $NH_4-N$ in both flood water and soil increased up to 20 days of incubation whereas that of $NO_3-N$ in flood water and in soil decreased over incubation time.

• The Transactions of the Korea Information Processing Society
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• v.3 no.1
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• pp.77-86
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• 1996

In managing a certain database, the integrity of data is very important. The important. The integrity constrains thus should be considered carefully when a database is designed and, after the database is created, it is required for a database manager to check continuously if some data contained in the database violate the integrity constraints considered. It is however not easy to check the violateion of integrity constraints when the size and the complexity of database are increased. This paper suggests a rule-based database verification system to relax the difficulty of checking the integrity violation, in which a database is coupled with a rule-based system including the knowledge about the integrity constraints. The rule-database verification system suggested accepts the model descriptions of an application domain, generates the knowledge base consisting of rules and facts by analyzing the model description and proceeds the verification process to check the integrity of the database.

• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.413-425
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• 2016

Potassium (K) is an element essential for plant growth. This study was aimed to examine the effects of three formulations of potash feldspar, powder, sand, and granule type on the growth of radish and beet in organic farming. 0.1% three formulations of potash feldspar were treated on the soil before transplanting 15 days-old seedlings of radish and beet in greenhouse. The results showed that all kinds of potash feldspar significantly increased shoot and root growth, and soluble solid contents excepted for root hardness in radish and beet. Among them, the powder type of potash feldspar was the most effective on foliage and root growth of radish and beet. Based on the results, it was confirmed that 0.1% potash feldspar treated in the rhizosphere of radish and beet can promote the growth of them.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.196-199
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• 2003

This experiment was conducted to evaluate the differences in physicochemical properties of soil, grain yield and milling recovery ratio and grain appearance of rice grown in long-term no-till and ordinary till systems. The paddy in no-till rice system was unploughed but straw-mulched for 15 years from 1988 to 2002 at the Experimental Paddy of Gyeongnam Agricultural Research and Extension Services, while the paddy in ordinary till system was ploughed and puddled every crop year, A 5cm organic layer was formed in 11-year no-till rice system, in which exchangeable cation and phosphate were accumulated. In no-till paddy organic matter, bulk density and solid phase of surface soil significantly increased, while pH, exchangeable cation, phosphate, liquid and gaseous phase decreased. Tillage made the very top soil soft, but made deep soil below 5cm significantly hard. In the 1st year of no-till, topsoil showed hard, but in the process of the time in no-till system, the top- and sub-soil showed softer, Yield and yield components of rice showed no differences between till- and no-till rice systems. Milling recovery ratio and grain appearance were not significantly different between no-till and till-rice systems.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.147-153
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• 1997

This experiment was carried out to clarify the effect of different fertilizer on growth and yield of Fritjllaria thunbergii in Chungbuk Rural Development Administration from 1993 to 1995. Emergence date was faster about 1 to 5 days in fertilizer application than that of non-fertilizer, and emergence ratio was lower about 2.4% to 35.7% in fertilizer application than that of non-fertilizer. Plant height was longer about 2.8cm to 10.6cm in fertilizer application than that of non-fertilizer, and leaf length and width had same tendencies. Bulb height was increased about 0.1 to 0.2cm in fertilizer application than 1.9cm in non-fertilizer and bulb width was increased about 0.5 to 0.7cm in fertilizer application than 2.2cm in non-fertilizer. Total yield was increased about 27% in N-P-K fertilizer, 24% in compost, 23% in compound fertilizer for garlic and 21 % in fowl dropping manure than 572kg/10a in non-fertilizer. Yield of marketable goods was high about 79% in compost. 72% in compound fertilizer for garlic and fowl dropping manure, and 69% in organic fertilizer than 229kg/l0a in non-fertilizer. Therfore, in the cultivation of Fritillaria thunbergii the application of organic fertilizer such as compost and fowl dropping manure was considered more profitable than the application of chemical fertilizer in middle region.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10a
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• pp.547-549
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• 1998

정보화 사회로 다가갈수록 정보보호 위협요소가 증가되고 있고, 이러한 위협요소와 증가는 정보통신 서비스의 활용을 저해하는 부요 문제점으로 대두되고 있다. 이에 따라, 본 연구실에서는 안전하고 신뢰성을 갖춘 EDI 시스템을 구축하기 위하여, '95년 개발 완료된 KT-EDI시스템을 토대로 암호화, 무결성 인증, 감사추적 등의 필수적인 정보보호 서비스를 제공할 수 있는 시스템을 개발하였고, 본 논문에서는 이에 구축사례를 기술한다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.4
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• pp.529-534
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• 1986

본 연구에서는 실차를 대상으로 유한요소 해석을 통하여 차체 및 차실의 구조 진동 및 음향모우드를 구한후 관련 실험에 의한 검증 및 보완을 통하여 설계단계에서 의 진동 및 소음수준을 저감시키는데 유용한 정보를 제공코저 하였다.

• Proceedings of the KIEE Conference
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• 2006.10d
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• pp.110-112
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• 2006

본 연구는 소형, 고효율 3kW급 고분자 전해질 연료공급 모듈용 에어블로워 개발에 있어 필수요소인 BLDC형 블로워 모터에 관한 것이다. 에어블로워의 목표출력(50W)에 최적화된 BLDC모터를 설계하기위하여 등가자기회로법과 유한요소법을 이용하였고, 모터를 제작하여 해석결과와 비교 검증하였다.