• 한국농공학회지
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• 제45권3호
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• pp.94-102
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• 2003

A hydrologic and water quality monitoring network were established in the Balkan-reservoir watershed, which has 29.79 $km^2$ in size, to analyze the characteristics of pollutant loading from an agricultural small watershed. Soil type, land use, hydrologic soil group, population and livestock were also surveyed to make clear the pollutant sources and to calculate the pollutant loadings by the unit loading factor method which was proposed by the Ministry of Environment. From the 5-year hydrologic monitoring results, sub-watersheds located in the upstream of the reservoirs showed higher average runoff ratio. The calculated daily pollutant loadings by the unit loading factor method from HP#2 sub-watershed in the downstream of Balkan reservoir, were much greater than observed.

• 한국환경보건학회지
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• 제15권2호
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• pp.51-58
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• 1989

In order to estimate unit loading factors of N, and P for controlling eutrophication of Youngsan lake. This study was performed in 4 kinds of pollutant sources from domestic sewage, industrial waste water, livestock stall waste water and drainage of agricultural area during the period from april to october 1988. These results were as follows: 1. The sewage flow for domestic waste water was 191.2 l/capita, day and that of the gray and toilet waste water among the domestic waste water were shown 152.9 l/capita, day(80%) and 38.3 l/capita, day(20%), respectively. 2. The unit loading factor total nitrogen(T-N) for domestic waste water was 7.582g/capita, day, and that of the gray and toilet waste water among the domestic waste water were 1.826g/ capita, day(24.1%) and 5.756g/capita, day(75.9%), respectively. The other hand, the unit loading factors of total phosphorus(T-P) for domestic waste water was 0.925g/capita, day, and that of gray and toilet waste water among the domestic waste water were 0.470g/capita, day(50.8%) and 0.455g/capita, day(49.2%), respectively. 3. In offering Price per million won, the T-P loading factor for drinking manufacture, confectionery manufacture, beer-manufacture and fibre manufacture in the industrial pollutant sources estimate to be 0.350g/day, 0.099g/day, 32.351g/day and 1.536g/day, while T-N loading factor about them in the industrial pollutant sources estimate to be 4.117g/day, 2.414g/day, 106.726g/day and 60.504g/day, respectively. 4. The T-P loading factor according to wash-water of milch cow and pig were 6.735g/day and 18.526g/day, in case of T-N they were 42.397g/day and 27.226g/day, respectively. 5. The T-P loading factor for pollutants drainage in the Paddy fields, fields and forests area were 0.082g/are, day, 0.014g/are, day and 0.002g/are, day, and the T-N loading factor were 0.309g/are, day, 0.158g/are, day and 0.064g/are, day, respectively. The diffrent of the loading factor for pollutants discharges in the agricultural area were resulted from the rainful intensity, the rainful, the amount of fertilization manure, and etc.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.83-86
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• 2003

To estimate the nutrient loads from an agricultural watershed, SWAT model and Unit Loading Factor method which was proposed by Ministry of Environment were applied for study watershed. The observed hydrologic and water quality data were compared with estimated methods for the Balhan HP#6 study watershed having an area of $3.86km^2$. The estimated nutrient loads were found to be similar values with the observed.

• 한국유기농업학회지
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• 제20권1호
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• pp.21-36
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• 2012

In this study, the assessment of livestock manure nitrogen loading for recycling farming in Yeoju-Gun carried out comparing manure units based on the cultivation areas and the N-amount of manure that are generated from livestock manure. Manure units (MU) are used in the permitting, registration, because they allow equal standards for all animals based on manure nutrient production. An MU is calculated by multiplying the number of animals by manure unit factor for the specific type of animal. The manure unit factor for MU determination was determined by dividing amounts of manure N produced 80kg N/year. In this study, manure unit by nitrogen concentration and amount of animal manure was calculated as follows: Hanwoo multiplied by 0.36, dairy cows multiplied by 0.8. swine multiplied by 0.105. The laying hens and broilers multiplied by 0.0079, 0.0049, respectively. The analysis of liquid manure unit per ha shows that the N loading by LMU is quite different by region. When it comes to nitrogen loading, the LMU per ha of cultivated land in excess of the N-amount was the highest in the Bukne-myeon province with 2.76 MU/ha, which is higher than the appropriate level. The Ganam-myeon province came next with 2.53 LMU. To be utilized as a valid program to build the environmentally friendly agricultural system, diverse measures shall be mapped out to properly determine manure units, evaluate N-loading and to properly manage their nutrient balance of each region.

• 한국수자원학회논문집
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• 제31권2호
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• pp.155-165
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• 1998

생활수준 향상과 식생활 변화로 인하여 생활용수 소비량이 증가함에 따라 일상생활에서 배출되는 오수의 양도 증가할 것으로 예측된다. 아파트 단지내 오수정화시설 및 하수처리장의 설계를 위해서는 먼저 인구에 근거한 오수량의 발생원단위를 알아야 한다. 이러한 자료는 하수처리의 운전이나 수질관리 계획 수립을 위해서도 꼭 필요한 것이다. 따라서 본 연구에서는 주택공사의 123개 관리소에 2년간의 급수량을 취합하여 거주인구에 따른 급수량을 분석하였고 그 중에 수도권 1개 단지와 지방권 1개 단지를 선정하여 시간별, 일별, 요일별, 계절별의 오수유입량을 직접 실측함으로써 실제 급수량과 비교를 통하여 오수유입 총량 및 거주인구에 따른 원단위를 계산하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.857-862
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• 2002

철도차량의 주행장치는 비틀림 선로를 주행할 경우 윤중감소가 발생하게 되며 이 값은 모든 하중 조건 및 공기스프링의 충기/배기 상태에서 UIC/ORE 보고서에서 규정한 기준치 60% 이내를 준수하여야만 한다. 이 논문은 인도 DMRC 전동차를 대상으로 시험을 실시하여 DMRC 선로 중 최악의 조건에서 UIC / ORE 에서 규정하고 있는 차량의 윤중감소율( Wheel Off-loading)의 기준을 만족하는 지에 대한 평가한 것을 기술하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1212-1213
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• 2011

PWM(pulse width modulation) rectifier has unit power factor and low harmonic distortion with high power conversion efficiency in entire loading range. These merits of PWM rectifier help the spread of DC distribution system. In addition, if multiple PWM rectifiers can be operated in parallel connection, maintenance process can be simple and reliability of power source can be advanced because of the hot swapping is available. The other way, the load unbalance among rectifiers can force a converter to stop by over current. The surge current by closed circuit composition between rectifiers can force switching devices damage. In this paper, some problems that can occur in case of parallel operation of PWM rectifiers and problem eliminating methods are considered.

• 농촌계획
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• 제7권1호
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• pp.27-36
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• 2001

Estimation of current and future loading from watershed is necessary for the sound management of water quality of an estuary lake. Pollution sources of point and non-point source pollution were surveyed and Identified for the Koheung watershed. Unit factor method was used to estimate potential pollutant load from the watershed of current conditions. Flow rate and water qualify of base flow and storm-runoff were monitored in the main streams of the watershed. Estimation of runoff pollutant loading from the watershed into the lake in current conditions was conducted by GWLF model after calibration using observed data. Prospective pollutant loading from the reclaimed paddy fields under cultivation conditions was estimated using the modified CREAMS model. As a result, changes of pollutant loading into estuary lake according to non-cultivation and cultivation conditions of reclaimed tidal land were estimated.

• Structural Engineering and Mechanics
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• 제55권2호
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• pp.435-459
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• 2015

Parametric resonance of shear deformable composite skew plates subjected to non-uniform (parabolic) and linearly varying periodic edge loading is studied for different boundary conditions. The skew plate structural model is based on higher order shear deformation theory (HSDT), which accurately predicts the numerical results for thick skew plate. The total energy functional is derived for the skew plates from total potential energy and kinetic energy of the plate. The strain energy which is the part of total potential energy contains membrane energy, bending energy, additional bending energy due to additional change in curvature and shear energy due to shear deformation, respectively. The total energy functional is solved using Rayleigh-Ritz method in conjunction with boundary characteristics orthonormal polynomials (BCOPs) functions. The orthonormal polynomials are generated for unit square domain using Gram-Schmidt orthogonalization process. Bolotin method is followed to obtain the boundaries of parametric resonance region with higher order approximation. These boundaries are traced by the periodic solution of Mathieu-Hill equations with period T and 2T. Effect of various parameters like skew angle, span-to-thickness ratio, aspect ratio, boundary conditions, static load factor on parametric resonance of skew plate have been investigated. The investigation also includes influence of different types of linearly varying loading and parabolically varying bi-axial loading.

• 교육시설 논문지
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• 제24권3호
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• pp.15-21
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• 2017

The purpose of this study was to develop satisfaction scale of school toilet that was completed repair work and examine its validity. In order to develop general and scientific satisfaction scale, the data was collected and analyzed targeting 3,694 participants from seventy schools which were elementary, middle, and high schools participating in improvement projects of school toilet in 2015 and 2016. Satisfaction scale of seventeen items was developed by using exploratory factor analysis and confirmatory factor analysis. Total Cronbach's ${\alpha}$ of seventeen items resulted in .950. Factor loading indicated over 0.6. Factor explanation of each item showed that was relatively high. This scale can be used to research unit school satisfaction and utilized for further research. The implication of this study was a reliable and valid instrument for measuring the satisfaction of school toilet.