• Weed & Turfgrass Science
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• 제4권3호
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• pp.199-208
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• 2015

본 연구는 경남지역의 밭에서 발생하는 잡초의 분포현황을 조사하기 위하여 수행하였다. 보리 재배지에서는 21과 55종, 마늘 재배지 22과 56종, 양파 재배지 19과 47종, 배추 재배지 26과 68종, 감자 재배지 22과 54종, 고구마 재배지 25과 62종, 고추 재배지 29과 87종, 옥수수 재배지 28과 79종, 콩 재배지 29과 84종이 발생되었다. 작목별 우점하는 초종은 보리 재배지 뚝새풀 20.7%, 마늘 재배지 황새냉이 12.3%, 양파 재배지 좀명아주 18.7%, 배추 재배지 쇠비름 8.1%, 감자 재배지 좀명아주 13%, 고구마 재배지 바랭이 12.6%, 고추 재배지 바랭이 12.6%, 옥수수 재배지 11.3%, 콩 재배지 바랭이 13.2%로 발생되었다. 동작물 재배지에서는 뚝새풀, 황새냉이 및 좀명아주가, 하작물 재배지에서는 바랭이, 쇠비름, 깨풀이 가장 문제시 되었다. 이러한 잡초 발생 정보는 경남지역 밭잡초 관리방안 수립에 기여할 것으로 판단된다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 1999년도 제3회 전자장의 생체영향에 관한 워크숍
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• pp.156-164
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• 1999

This paper shows that the configuration of power transmission lines currently in place is suitable on the basis of calculated magnetic field strengths. The magnetic fields were computed for typical current distributions on power transmission lines for electric railways, which are characterized by severe load fluctuations and phase distortions. The result of the numerical analysis are compared with th ELF guidelines of magnetic fields from several case studies. The final conclusion reached in that effects of the magnetic fields near power transmission lines for electric railways are not significant enough to cause a biological safety concern.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 가을 학술발표회 논문집
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• pp.201-205
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• 1999

An analytical study on the stability of steel plates in the presence of magnetic fields is carried out based on a model which accounts for the nonlinear field-structure interaction. The resultant force system arising from the interaction between the magnetic fields and ferromagnetic plates is derived using the variational principle. The bending and buckling problems of steel plates in oblique magnetic fields are investigated with the aid of the finite element method. Numerical results reveal some interesting features of the magnetoelastic buckling phenomenon.

• 농업과학연구
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• 제44권3호
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• pp.325-331
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• 2017

This study was conducted to investigate the dominance and distribution of weed species in organic and conventional paddy fields. The organic paddy fields were maintained for organic farming for more than five years in Anseong, Gyeonggi province of Korea. According to the Braun-Blanquet method, 42 and 36 weed species were found in the organic paddy fields in 2015 and 2016, respectively, while 38 and 36 weed species were found in the conventional paddy fields in 2015 and 2016, respectively. As a result of two years' survey, 53 species from 24 families in the organic paddy fields were identified and classified as 32 annuals, 3 biennials and 18 perennials. In conventional paddy fields, 51 species from 24 families (30 annuals, 6 biennials, and 15 perennials) were identified. According to the classification by family, the most abundant weed species were Compositae (9 species), followed by Poaceae (8 species) and Polygonaceae (6 species) in organic paddy fields. In conventional paddy fields, Compositae (9 species) were the most abundant weed species, followed by Cruciferae (6 species), Poaceae, Polygonaceae, and Cyperaceae. This result indicates that the difference in diversity of weeds in paddy fields was influenced more by the agricultural environment than the type of cultivation. Our results could be used as a base data to control the occurrence of weed species in the paddy fields.

• Applied Science and Convergence Technology
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• 제24권6호
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• pp.237-241
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• 2015

The reactor impedance is calculated for a planar-type cylindrical inductively coupled plasma source by expanding the electromagnetic fields into their Fourier-Bessel series forms including the three-dimensional shape of the antenna. The mode excitation method is utilized to determine the electromagnetic fields based on a Poynting theorem-like relationship. From the obtained electromagnetic fields, a tractable form of the reactor impedance is obtained as a function of various plasma and geometrical parameters and applied to carry out a parametric study.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1595-1596
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• 2006

In this study electromagnetic fields under power lines were derived by dipole antenna theory and electric fields under high voltage power lines were discussed with dependence of power factor cos $\phi$. And also electromagnetic fields under 3 phase power lines with horizenal and vertical configurations were formulated.

• 한국농공학회논문집
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• 제66권2호
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• pp.53-62
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• 2024

This study assessed the efficiency of reducing soil erosion and suspended sediment through the restoration of alpine unauthorized and illegally cultivated fields, using the SWAT (Soil and Water Assessment Tool) model in the Mandae District. The results showed that in Scenario 5, which involved restoring unauthorized and illegal fields within forests, along rivers (banks), and in ditch areas were restored to their original land categories, achieved the highest efficiency in reducing average annual soil erosion and suspended sediment, with reductions of 8.1% and 4.5%, respectively. In particular, it was confirmed that the restoration of unauthorized and illegal fields within forested areas has a significant impact. This demonstrated that the restoration of unauthorized and illegal agricultural fields can substantially reduce the soil erosion and suspended sediment attributable to non-point source pollution. Our findings highlight the importance of managing these unauthorized and illegal agricultural activities in developing sustainable strategies within non-point source pollution management areas. This study is expected to provide important basic data to effectively establish water quality improvement strategies in the region of non-point source pollution management.

• 대한간호학회지
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• 제31권6호
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• pp.1109-1118
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• 2001

The purpose of this study was to analyze the appraising frame and the accreditation system of universities in both Korea and the United Sates, as well as developing a standard plan to appraise 4 year nursing education institutions in Korea. Research design of this study was descriptive comparative research. The results of the research can be divided into six fields, educational purposes, educational courses, students, faculty, facility .equipments and administration.finance in Korea. Then the results were further categorized into seven fields : mission and governance, faculty, students, curriculum and instruction, resources, educational effectiveness and integrity. Thus Korean appraising frames were suggested to have eight fields of standard. The fields are philosophy and purposes of educational institution, educational courses and instruction, students, faculty, facility .equipments, adminstration.finance, educational effectiveness and integrity.

• Journal of Multimedia Information System
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• 제6권4호
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• pp.323-328
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• 2019

In this paper, a method of constructing an advanced sequential circuit over finite fields is proposed. The method proposed an algorithm for assigning all elements of finite fields to digital code from the properties of finite fields, discussed the operating characteristics of T-gate used to construct sequential digital system of finite fields, and based on this, formed sequential circuit without trajectory. For this purpose, the state transition diagram was allocated to the state dependency code and a whole table was drawn showing the relationship between the status function and the current state and the previous state. The following status functions were derived from the status function and the preceding table, and the T-gate and the device were used to construct the sequential circuit. It was confirmed that the proposed method was able to organize sequential digital systems effectively and systematically.

• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.185-193
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• 2003

Basic flow fields of two dimensional V flames were examined as a preliminary work to study the instability of premixed flame with vorticity generation. Laminar premixed propane and methane flame were anchored by electrically heated wire to make two dimensional V flames. Flow fields were measured mainly by PIV(Particle Image Velocimetray) and the results were compared with those obtained by LDV(Laser Doppler Velocimetry) to confirm their reliability. Because the curvatures of V flames are so small, V flames were locally assumed to be inclined planar flames in gravitational field. The measured flow fields were locally compared with those of analytical solutions, which showed the qualitatively similar results. In downstream region, the vorticity fields were nearly constant except region near the center line, which support the assumption of locally one dimensional flame. Besides it was tried to find experimentally the similarity of flow fields in downstream region. Finally, stability diagram of propane and methane flames were drawn for the equivalence ratio less than one and the wide range of mean velocity.