• Title/Summary/Keyword: 2 order system

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Mapping Technique for Flood Vulnerable Area Using Surface Runoff Mechanism (지표유출메커니즘을 활용한 홍수취약지구 표출 기법)

  • LEE, Jae-Yeong;HAN, Kun-Yeun;KIM, Hyun-Il
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.4
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    • pp.181-196
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    • 2019
  • Floods can be caused by a variety of factors, and the main cause of floods is the exceeding of urban drainage system or river capacity. In addition, rainfall frequently occurs that causes large watershed runoff. Since the existing methodology of preparing for flood risk map is based on hydraulic and hydrological modeling, it is difficult to analyse for a large area because it takes a long time due to the extensive data collection and complex analysis process. In order to overcome this problem, this study proposes a methodology of mapping for flood vulnerable area that considered the surface runoff mechanism. This makes it possible to reduce the time and effort required to estimate flood vulnerabilities and enable detailed analysis of large areas. The target area is Seoul, and it was confirmed that flood damage is likely to occur near selected vulnerable areas by verifying using 2×2 confusion matrix and ROC curve. By selecting and prioritizing flood vulnerable areas through the surface runoff mechanism proposed in this study, the establishment of systematic disaster prevention measures and efficient budget allocation will be possible.

A study on the estimation of container terminal capacity and its implication to port development planning of Korea (국내 컨테이너 부두시설 확보제도 개선방향 연구)

  • Yang, Chang-Ho
    • Journal of Korea Port Economic Association
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    • v.26 no.3
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    • pp.198-220
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    • 2010
  • This paper investigate the problems of standard container port handling capacity in establishing national port development plan in Korea. Considering container port developing, it's not easy to adopt container port service quality parameters such as lay time constraint of very large container ships by using the standard guideline of container port handling capacity. A simple methodology that connects vessel waiting to service time(w/s) and berth occupancy to costs has been used to evaluate the performance of a container terminal. But the total handling capacity have to be calculated by the performance of the handling system and number of equipments and layout of terminal by using computer simulation that represents of reality events needs to be performed by probabilistic techniques. A simulation model of estimation of container terminal capacity is introduced in order to establish a hub terminal for very large container ships that focus the port's quality of service and also suggest as tool for policy maker to justify a required port investment.

The 'Trojan Horse' of Old Age Income Security System Retrenchment in Korea : the Examination of Policy Changes on Basic Old Age Pension for the Rich (기초연금제도 축소의 '트로이 목마' : 부유층 노인 수급제한조치에 대한 실증적 비판)

  • Kim, Seongwook;Han, Sinwil
    • Korean Journal of Social Welfare
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    • v.66 no.3
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    • pp.231-251
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    • 2014
  • Recently, Korean government documented the plan to cope with the situation related to rich pensioners of Basic old-age pension. The purpose of this paper is to verify that how many rich pensioners are existing and to evaluate government reform plan's validity and effect. Main results are as follows; firstly, if the definition of rich pensioners is on the top 10%, the proportion of them would form 2.9% of total. And then, an amount of expenditure for them is only 2.6% of total. Secondly, in terms of disposable income, debt, and transfer income from child, the household who would be applied by government's plan is not richer than other household who is in the same living standard. And then, if the government's plan enforced, the effect might be very small. Lastly, the plan of government will discriminate against persons who support their parent. As a result, Basic old-age pension will be worsen. This paper should underline that the government's reform is only the 'hidden' retrenchment strategy in order to introduce a standard of the obligation to support own parent in the state without scientific prediction and serious discussion of negative public opinion. That is why, this is the same as the 'Trojan Horse'.

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Analysis of the Outdoor Design Conditions for Greenhouse Heating and Cooling Systems in Korea (온실의 냉난방시스템 설계용 외부기상조건 분석)

  • Nam, Sang-Woon;Shin, Hyun-Ho
    • Journal of Bio-Environment Control
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    • v.25 no.4
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    • pp.308-319
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    • 2016
  • In order to set the outdoor weather conditions to be applied to the design standard of the greenhouse heating and cooling system, outdoor air temperature and heating degree-hour for heating design, dry bulb temperature, wet bulb temperature and solar irradiance for cooling design were analyzed and presented. For every region in Korea, we used thirty years from 1981 to 2010 hourly weather data for analysis, which is the current standard of climatological normal provided by KMA. Since the use of standard weather data is limited, design weather conditions were obtained using the entire weather data for 30 years, and the average value of the entire data period was presented as a design standard. The design weather data with exceedance probability of 1, 2.5, and 5% were analyzed by the TAC method, and we presented the distribution map with exceedance probability of 1% for heating and 2.5% for cooling which are recommended by design standards. The changes of maximum heating load, seasonal heating load and maximum cooling load were examined by regions, exceedance probabilities, and setpoint temperatures. The proposed outdoor design conditions can be used not only directly for the greenhouse heating and cooling design, but also for the reinforcement of heating and cooling facilities and the establishment of energy saving measures. Recently, due to the climate change, sweltering heat in summer and abnormal temperature in winter are occurring frequently, so we need to analyze weather data periodically and revise the design standard at least every 10 years cycle.

Development of a Solar Powered Water Pump by Using Low Temperature Phase Change Material ­ System Construction and Operation Analysis ­ (저온 상변화 물질 특성을 이용한 태양열 물펌프 실용화 연구개발(II) ­시스템 구성 및 작동분석)

  • 김영복;이양근;이승규;김성태;나우정;민영봉
    • Journal of Animal Environmental Science
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    • v.9 no.2
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    • pp.69-78
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    • 2003
  • In this study, the energy conversion equipment from the radiation energy to mechanical energy by using n­pentane as the operating fluid was constructed and the performance to pump the water was tested for the utilization of solar powered water pump. The equipment was designed optimally, after the theoretical analyses of the water pumping head and water quantity per cycle were done. The pentane vapour temperature in the condenser and the temperature of the outlet water from the condenser became lowered and the heat transfer rate became higher with decreasing the water inlet level to the condenser. The temperature difference between the condenser and the water tank was significant. Therefore, the distance between the water tank and condenser was recommended to be shorten and the diameter of their connecting pipe was recommended to be narrow in order to reduce the resistance of the fluid passage and improve the heat transfer rate. The amount of water pumped was 1.6­2.4 liters. Mass flow rate of the cooling water became lowered when the cooling water pipe was prolonged from the condenser to improve the heat transfer rate.

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Mineralization of Nitrogen in Soils under Paddy-Upland Switching Cultivation Systems (답전윤환토양(沓田輪換土壤)에서 질소무기화(窒素無機化)의 특성(特性)에 관(關)한 연구)

  • Ahn, Sang-Bae;Motomatsu, T.;Yeon, Beong-Yeal;Yuk, Chang-Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.25 no.2
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    • pp.133-137
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    • 1992
  • The rate and pattern of soil nitrogen mineralization were investigated under conditions of a paddy-upland switching cultivation system. Experimental results obtained are as follows 1. Amounts of soil nitrogen mineralized were different in the order of potato-cabbage>soybean>continuous paddy plot for the first year, but potato-cabbage>continuous paddy>soybean plot for the second year, respectively. 2. In the third year cropping under upland condition a higher amount of soil nitrogen was found mineralized at the plot of continuous upland cultivation than at the alternate paddy-upland switching plot in the case of potato-cabbage, on the contrary, however, the higher amount was found at the alternate paddy-upland switching plot in the case of soybean cultivation. 3. The amounts of total soil nitrogen and carbon were lower in paddy-upland switching plots than in continuous paddy plots. This trend is significant in soybean plots. 4. A positive correlationship was found between phosphate buffer solution method for available nitrogen and submerged soil method for $NH_4-N$, both being utilized for the estimation of soil fertility.

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Fact-finding Survey on Occurrence of Weeds and Herbicide Usage for Paddy Rice Cultivation in Gyeonggi Province, Korea (경기지역 논잡초 발생양상 및 제초제 사용실태)

  • Won, Taejin;Park, Jungsu;Kim, Soonjae;Kim, Heedong
    • Weed & Turfgrass Science
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    • v.2 no.4
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    • pp.352-357
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    • 2013
  • A survey was performed to investigate major paddy field weeds and frequently used herbicides in Gyeonggi province, Korea in order to establish a system to efficiently control herbicide-resistant weeds. The dominant paddy field weeds included Echinochloa spp. (22%), Eleocharis kuroguwai (14%), Sagittaria trifolia (13%), Scirpus juncoides (12%), Monochoria vaginalis (9%) and Sagittaria pygmaea (7%), and the most widely used herbicides were butachlor 33% CS (25%), benzobicyclon + fentrazamide + imazosulfuron 11.5% SC (9%), cyclosulfamuron + mefenacet 22.2% SC (9%), butachlor 5% GR (6%), and oxadiazon 12% EC (6%) in Gyeonggi province, Korea. Many paddy rice growers considered S. juncoides, M. vaginalis, S. pygmaea and C. difformis as herbicide-resistant weeds. An extensive research deserves to be conducted to monitor occurrence of herbicideresistant paddy weeds in Gyeonggi province, Korea.

Stabilization Performance Evaluation of Filter(pH) Using Ionic Water Generator (이온수기 필터(pH)의 안정화 성능평가)

  • Nam, Sangyep;Kwon, Yunjung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.3
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    • pp.199-205
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    • 2015
  • This study is about ionic water generator filter Recently, a lot of people feel deep interest in health and drinking water. And there are various types of water. Ionic water generator is a system with special function, and can be classified as a medical device and should be manufactured after approval from the Food and Drug Administration. Basically ionized water is different from the packaged and stored water. When the tap water or ground water passes through the various filters of ionic water generator, it turns to the purified water of pH7 ~ 7.5 and we can electrolyze that water into anion and cation by diaphragm. And in negative electrode side, we can get alkaline water with calcium ($Ca^+$), potassium ($K^+$), magnesium ($Mg^+$), sodium ($Na^+$) for body. In general, we can change pH value from 5 to 9 of ionizer by controlling the level of electrolysis voltage in the ionizer. In general, 1stage (pH8), 2stage (pH8.5), 3stage (pH9), 4stage (pH9.5) are used as the alkaline ionized water, -1Stage (pH6.0), -2 stage (pH5.0) are used as the acidic water. But in early stage, the water that passed through filter was weakly alkaline water and that was problem. Therefore, when filter condition is stable, the pH and ORP value of water is different with the early one. the initial setting pH value of the ionizer was confirmed that changes significantly. In order to resolve this problem we need to wash filter for some period time and neutralize by acidification treatment of the filter.

Saccharification of Foodwastes Using Cellulolytic and Amylolytic Enzymes from Trichoderma harzianum FJ1 and Its Kinetics

  • Kim Kyoung-Cheol;Kim Si-Wouk;Kim Myong-Jun;Kim Seong-Jun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.1
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    • pp.52-59
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    • 2005
  • The study was targeted to saccharify foodwastes with the cellulolytic and amylolytic enzymes obtained from culture supernatant of Trichoderma harzianum FJ1 and analyze the kinetics of the saccharification in order to enlarge the utilization in industrial application. T. harzianum FJ1 highly produced various cellulolytic (filter paperase 0.9, carboxymethyl cellulase 22.0, ${\beta}$-glucosidase 1.2, Avicelase 0.4, xylanase 30.8, as U/mL-supernatant) and amylolytic (${alpha}$-amylase 5.6, ${\beta}$-amylase 3.1, glucoamylase 2.6, as U/mL-supernatant) enzymes. The $23{\sim}98\;g/L$ of reducing sugars were obtained under various experimental conditions by changing FPase to between $0.2{\sim}0.6\;U/mL$ and foodwastes between $5{\sim}20\%$ (w/v), with fixed conditions at $50^{\circ}C$, pH 5.0, and 100 rpm for 24 h. As the enzymatic hydrolysis of foodwastes were performed in a heterogeneous solid-liquid reaction system, it was significantly influenced by enzyme and substrate concentrations used, where the pH and temperature were fixed at their experimental optima of 5.0 and $50^{\circ}C$, respectively. An empirical model was employed to simplify the kinetics of the saccharification reaction. The reducing sugars concentration (X, g/L) in the saccharification reaction was expressed by a power curve ($X=K{\cdot}t^n$) for the reaction time (t), where the coefficient, K and n. were related to functions of the enzymes concentrations (E) and foodwastes concentrations (S), as follow: $K=10.894{\cdot}Ln(E{\cdot}S^2)-56.768,\;n=0.0608{\cdot}(E/S)^{-0.2130}$. The kinetic developed to analyze the effective saccharification of foodwastes composed of complex organic compounds could adequately explain the cases under various saccharification conditions. The kinetics results would be available for reducing sugars production processes, with the reducing sugars obtained at a lower cost can be used as carbon and energy sources in various fermentation industries.

Preference and Service Satisfaction of Campsite Visitors - Focus on Wolaksan.Sokrisan National Park - (야영장 이용객의 선호요인과 이용 만족도 - 월악산.속리산국립공원을 중심으로 -)

  • Ryu, Jae-Seung;Kim, Ha-Jong;Kim, Jin-Seon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.3
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    • pp.11-20
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    • 2009
  • The purpose of this study is to analyze visitor preferences and the degree of service satisfaction for campsites and investigate factors that influence visitor satisfaction so that the study may provide proper data needed to build and operate campsites. The results are as follows. 1. It was found that men use campsites more frequently than women. Campsites are most often used by those in their thirties, the highest percentage out of all the age groups. Relaxation proved to be the main purpose for using campsites. It was also found that usually 2 to 4 people use a campsite at a time, the highest percentage as well. 2. The factor-analysis of 13 items related to campsite satisfaction can be divided into facilities, psychological factors, the surrounding-environment and access. 3. It was found that the satisfaction of lavatories has the most influence in the facilities factor. The satisfaction on the intention to revisit has the most influence in the psychological factor. The landscape element has the most influence in regards to the surrounding-environment and the guidance and sign system has the most influence in the access factor. 4. It was found that the factors that most influence overall satisfaction are facilities factor, psychological factors and the surrounding environment, in that order.