• Title/Summary/Keyword: Water saving

검색결과 613건 처리시간 0.038초

Mitigation of Greenhouse Gas Emissions (GHGs) by Water Management Methods in Rice Paddy Field

  • Kim, Gun-Yeob;Park, Woo-Kyun;Lee, Sun-Il;Lee, Jong-Sik;Choi, Eun-Jung;Na, Un-sung;Jang, Hee-Young;Suh, Sang-Uk
    • 한국토양비료학회지
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    • 제48권5호
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    • pp.477-484
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    • 2015
  • Environmental effect of water-saving irrigation on the emissions of greenhouse gases (GHGs) has not been well investigated. The objective of this study was to measure the effect of water-saving irrigation on GHGs as well as water use and rice production yield in paddy field condition in Korea. Four experimental runoff plots of 4x35 m in size were prepared at an existing paddy field. GHGs emission was measured during the 2012~2013 growing seasons while a Japonica rice variety was cultivated. Four different water management methods, 1) Continuous Flooding (CF), 2) Intermittent Drainage (ID), 3) Water Saving (WS), and 4) CF+WS, were used during a rice growing season to compare the effects of water management methods on GHGs emission. CF method is flooding all the time, ID method makes paddy water drained 40 days after transplanting for about two weeks, WS method maintains 2~3 cm water-level, which should be refilled when the water-level decreased to about 0 cm, and CF+WS method combines CF method before 30 days after transplanting (DAT) and WS method after 30 DAT. Regardless of water management methods, paddy field water was drained about 30 days before harvest. Amount of GHGs emission from WS plot was reduced by 69.3% compared to that from CF plot and by 59.0% compared to that from ID plot. Amount of GHGs emission from CF+WS plot was reduced by 60.7% compared to that from CF plot and by 47.5% compared to that from ID plot. Weed occurrence in CF+WS plots was reduced to 62.2% in comparison with the WS plot, implying that CF+WS plot showed the best effect to mitigation of the greenhouse gas emission in the atmosphere.

친환경 하수처리장을 위한 에너지 절감 방법 및 사례 (Energy saving methods & examples for eco-friendly sewage treatment plants)

  • 한창동;임동희;유재홍;황인광;김동진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.1366-1367
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    • 2011
  • 저탄소 녹생성장의 국가정책에 부응하고 친환경 하수처리장 운영관리 및 에너지 자립률 향상을 위해 신재생에너지 설비 사용과 고효율 전기설비를 적용하여 안정적 하수처리장 운영을 하고자 함.

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보리 산물처리에 의한 품질변화와 생력효과 (Effects of Post-Harvest Bulk Management System Using Rice Processing Complex on Labor Saving and Quality of Barley)

  • 이춘우;윤의병;구본철;백성범;손영구;서세정;남중현;김완석
    • 한국작물학회지
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    • 제47권6호
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    • pp.475-478
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    • 2002
  • 보리의 산물처리 확대를 위한 기초자료를 제공하고자 미곡종합처리장을 이용한 보리 산물처리시 품질변화와 생력효과를 조사 분석한 결과는 다음과 같았다. 1. 정립율은 2.5-2.2mm의 비율이 가장 많았으며, 건조방식에 따른 차이는 없었다. 2. 경도는 건조방식에 따른 차이는 없었고, 색도는 산물건조와 관행인 천일건조와 차이는 없었다. 3. 흡수율은, 고형용출물, 퍼짐성 등의 취반특성은 건조방식에 따른 차이는 없었다. 4. 산물처리에 의하여 관행의 ha당 46시간에 비하여 21시간으로 54.3%의 생력효과가 있었고, 수확 후 관리는 54.3% 생력화되었다. 5. 산물처리로 수확 후 관리노력이 관행에 비하여 ha당 25시간이 절감되어 101,83원의 경영비 절감효과가 있었다.

Membrane Processes for Energy Saving in Japan

  • Nakao, Shin-ichi
    • 한국막학회:학술대회논문집
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    • 한국막학회 1994년도 제2회 하계분리막 Workshop
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    • pp.45-58
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    • 1994
  • Over the last 20 years, membrane separation processes, such as reverse osmosis, ultrafiltration and microfiltration, have been widely adopted by different industries. Commercial uses of membrane have displaced conventional separation processes, such as distillation, evaporation, precoat filter and so on. Membrane separation processes are often more capital and energy efficient when compared with conventional separation processes. Membrane devices and systems are almost always compact and modular. These are the well-known advantages of membrane separation processes. The disadvantage of the membrane process is that the process does not have scale merit and thus the membrane process is suitable for the small and middle size applications. Energy saving is, of course, the biggest advantage of the membrane process, and in many industries the membrane processes are employed because of this reason. Membrane process has other big advantage. In many applications membrane processes provide much higher quality of product than conventional processes. The example is ultrapure water production by membrane processes in semiconductor industry. Conventional technologies never offer such good quality of pure water. If you can obtain both energy saving and higher quality of product at the same time by membrane processes, this is the best application of membrane processes. One example is the concentration of orange juice by membrane, which has already been commercialized in Japan. Comparing with the conventional vacuum evaporation process, juice concentrated by the membrane process has much better taste and flavor and the energy consumption in the membrane process is much less than the evaporation process. In this paper, first membrane separation technology will be classified and then Japanese membrane manufacturers and new modules and devices under development in Japan will be introduced. Fourth energy saving in membrane process will be discussed and finally practical applications of membrane processes in Japan will be shown.

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공동주택 간헐난방시스템의 에너지 절감 및 열환경 개선방안 연구 (Strategy of Energy Saving and Thermal Environment Improvement for Intermittent Heating System in Apartment Buildings)

  • 안병천;이태원
    • 설비공학논문집
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    • 제17권1호
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    • pp.88-93
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    • 2005
  • In this study, the operational characteristics on heating performance and energy consumption for intermittent hot water heating system in apartment buildings were research by simulation. The effects of apartment inlet hot water temperature and operation time per day on energy consumption and indoor thermal environment are investigated. The strategy of energy saving and thermal environment improvement is suggested in comparison with the existing ones.

동적계획법을 이용한 고온수배관의 최적보온설계에 관한 연구 (A study on the optimal design for heat insulation of hot water piping systems using a dynamic programming)

  • 유희한;하주식
    • Journal of Advanced Marine Engineering and Technology
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    • 제11권1호
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    • pp.39-52
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    • 1987
  • Recently, the design problem of heat insulation have been reappraised in the aspect of energy saving due to the rising trend of energy cost. For example, that design problem is increasingly requsted in the fields of accommodation air conditioning systems, hot water supply systems, cargo handling systems, district heating or cooling systems. The rational design of heat insulation of piping systems can not only improve the overall efficiency of energy transfer but also give energy saving. In this paper, the heat insulation problem of district heating systems is therefore modeled as the multi-stage decision processes, suitable for dynamic programming technique. And take the object function as the sum of heat insulation material cost involved construction cost and heat loss cost, and propose the design method to minimize the object function for overall piping systems by dynamic programing. Effectiveness of design method presented here is proved by a computer simulation.

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Energy Simulation for Energy Saving Opportunities

  • Lee, E.J.;J.H. Yoon;Y.H. Kang;H.S. Jeon
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 1995년도 춘계학술발표회 초록집
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    • pp.88-93
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    • 1995
  • The purpose of this study is to introduce the energy simulation program BLDSYM, verify the approach. and demonstrate the energy saving opportunities. A case study model for Hoover Middle School, OK USA has been introduced as a base case simulation. Air-side variable air volume (VAV) and water-side variable flow hydronic (VFH) system have been recommended, modeled and simulated to quantify the energy savings compared with the base system, which is typically constant air and water flow system. More than 30 % of energy savings could be obtained with the optimum variable flow system.

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온실가스배출 감소와 연료절감을 위한 최적 운용절차 방안에 관한 연구 (A Study of Optimized Operation for CO2 Emission and Aircraft Fuel Reduced Operation Procedures)

  • 황정현;이태광;황사식
    • 한국항공운항학회지
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    • 제21권4호
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    • pp.62-70
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    • 2013
  • As the aviation industry looks to the future, fuel saving and $CO_2$ emission reduction play a dominant role in meeting the business challenges presented by global financial uncertainty. The IATA and International Government effort to save fuels, and then save 4 billion gallons of fuel burned, while reducing $CO_2$ emissions by 34 million tons. The various reduction methods adapted airlines and airports. We focused on optimized flight operation procedures for saving fuel and reduction emission cases. IATA and Canada government research reports focused on four methods that Engine Core Washing, Portable Water Management, Single Engine Taxi, APU limit operation. Apply to domestic airlines fuel data, Engine Core washing was saving more than Twenty-four thousand tons $CO_2$ emissions.

Cost Effective Quasi-Resonant Soft Switching PWM High Frequency Inverter With Minimum Circuit Components for Consumer IH Cooker and Steamer

  • Sugimura, Hisayuki;Eid, Ahmad-M.;Nakaoka, M.;Lee, H.W.
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.134-139
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    • 2005
  • This paper presents a cost effective quasi-resonant soft-switching PWM high frequency inverter with minimum circuit components. This inverter can achieve wider soft commutation, simpler power circuit configuration, smaller volumetric size, lower cost and wider power regulation range, higher-efficiency as compared with single ended quasi-resonant ZVS-PFM inverter and active voltage clamped quasi-resonant ZVS-PWM inverter. The operation principle of the proposed inverter is described on the basis of the simulation and experimental results, together with its operating performances in steady state. The operating performances of this unique proposed high frequency inverter based on ZVS and ZCS arms-related soft commutation principle is evaluated and discussed as compared with the active voltage-clamped ZVS-PWM inverter and a conventional single-ended ZVS-PFM inverter. The practical effectiveness of a novel type quasi-resonant soft-switching PWM high frequency inverter using IGBT is actually proved for consumer induction heated appliances as rice cooker, hot water producer, steamer and super heated steamer. The extended bidirectional circuit topology of quasi-resonant PWM high frequency inverter with minimum circuit components is demonstrated, which operate as the direct frequency changer.

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