• 생물환경조절학회지
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• 제22권4호
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• pp.341-348
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• 2013

본 연구에서는 토성에 따른 물의 이용효율을 높이면서 재배 작물의 생산성을 최대화하기 위한 효율적인 자동관개 로직을 개발하고자, 수분장력값을 관수 개시점으로 하여 물 공급 유지와 멈춤을 간헐적으로 수행하는 펄스형 관개방식과 측정한 수분장력값을 이용하여 토양수분량을 예측해 재배작물에 적합한 물량을 추가 투입하는 필요물량계산 관수방식을 적용하여 토성이 다른 실험베드에서 2년간 토마토 작물을 재배하면서 토양수분 함량과 장력의 변화를 측정비교하였다. 물공급 30초와 멈춤 30분 및 15분 조건을 이용한 펄스형 관수방식과 필요물량계산 방식에서 얻어진 수분장력값은 목표한 -20kPa 조건에 비해 각각 -42~-8kPa, -20~-10kPa로 나타나 필요물량 계산방식이 균일한 수분장력을 유지하는 측면에서는 유리하였으나 토양수분상태는 상대적으로 습하였다. 공시 토성 모두에서 수분함량은 수분장력에 비해 시간반응이 빠르면서 물공급에 따라 비례적으로 증가하는 경향이 뚜렷하였다. 수분변화 값은 펄스형 관수와 필요물량계산 관수방식의 경우 사양토 기준으로 각각 17~24%, 19~31%로서 펄스형 관수방식이 수분변화 값이 작으면서 시간에 따라 안정적인 값을 유지한 것으로 나타났는데 이는 물공급에 따른 수분함량의 시간변화가 수분장력에 비해 뚜렷하게 빠름과 관계가 있는 것으로 판단하였다. 이러한 결과로부터 펄스형 관수방식은 수분함량값을 이용하여 수분을 조절하는 것이 유리함을 의미한다.

• 한국화재소방학회논문지
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• 제33권1호
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• pp.85-91
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• 2019

이 연구는 불꽃파장 감지기술과 불꽃영상 감지기술을 융합한 도로터널용 자동소화설비의 화재감지성능을 평가하기 위한 실험이다. 화재감지성능을 향상시키기 위한 이 융합기술은 화재 시 화원의 위치를 파악하고, 노즐을 화원으로 향하여 화재가 발생한 장소에만 가압수를 방사함으로서 화재진압에 따른 수손피해를 줄이는 효과를 얻을 수 있었다. 도로터널의 화재 중 불꽃 및 연기가 선행되는 상황에서 각각 15 m, 20 m, 25 m, 30 m, 35 m 거리에 $70cm{\times}70cm$의 목표물을 두었을 때 화원의 위치를 파악하는지를 실험하였다. 실험결과 농연의 간섭으로 인해 자외선 및 삼파장적외선센서의 감지능력이 감쇠되는 결과를 확인하였다. 또한 농연으로 인해 불꽃이 가려진 경우 이미지센서가 농연을 감지하여 화재신호를 발신함을 확인하였다.

• 한국토양비료학회지
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• 제43권5호
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• pp.540-545
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• 2010

본 연구는 시설재배오이의 적정 관개시점의 평가를 통한 물 관리 방안을 설정하기 위하여 수행하였다. 경기도 연천군 전곡읍 소재의 오이 시설재배 농가에서 Tensiometer를 이용한 자동관개시스템을 구축하고, 이를 이용하여 관개시점이 15, 20, 30, 40 kPa인 4개의 처리구를 두어 일반농가의 관행 관개방법과 비교하여 오 이의 생산력과 물의 이용효율을 평가하였다. 관개방법에 따른 오이과실의 수량과 당도는 통계학적 차이는 없었으나 15 kPa보다 20, 30 kPa, 관행 처리구에서 각각 수량이 6%, 7%, 9% 높게 나타냈으며, 과실의 당도는 30 kPa 처리구에서 가장 높은 값인 4.1$^{\circ}brix$, 관행과 40 kPa에서 가장 낮은 값인 3.7 $^{\circ}brix$를 나타냈다. 건물중은 30 kPa에서 가장 큰 값을 나타내었으며 15, 20, 30 40 kPa처리구의 식물체 수분함량은 92, 86, 85, 84%로 조사되었다. 오이의 생육 기간 중 사용된 관개량은 관행 > 15 kPa > 20 kPa > 30 kPa > 40 kPa 순이었으며, 절수율은 관행을 기준으로 15 kPa 처리구에서 46%, 20 kPa 처리구에서 48%, 30 kPa 처리구에서 58%, 40 kPa 처리구에서 69%가 절약되었다. 1 kg의 과실을 생산하는데 사용되는 물이용률은 관행이 가장 비효율적이며, 관행에 비해 15, 20, 30, 40 kPa처리구가 관행구보다 36~67%정도 물이 적게 사용되었다. 과실수량과 당도 등에 처리별 유의한 차이가 없으므로 30~40 kPa수준으로 관개 시점 설정 시 60%이상의 물절약이 가능 할 것으로 판단된다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.119.2-119
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• 2001

The inspection of a meter is an action that measures the amount of electricity, water and gas used to impose user on a charge. In past days, a meter who visit consumer to look over meter and write data to the ledger and then go back his office to calculates the inspection of a meter. On the other hand, the AMR(Automatic Meter Reading) is remote control system to measure the amount of utility used and monitor a condition of the meter. A study about AMRS is started at 1960 all over the world and a successful application example is presented continuously in American, Europe and Japan etc. In this paper we use a check meter that is used in past days and we add an AMR to it. AMR receives data that is the amounts of electricity from the check meter and stores those ...

• 한국안전학회지
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• 제26권4호
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• pp.34-40
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• 2011

This paper is purposed to develop an leakage current detecting system(LCDS) which can prevent electrical fires on breaker capacity expansion as well as ruptures of XL(Extra long) pipelines and power failure by operation of ELB(Earth leakage breaker) at auto water machine in winter. In order to develop LCDS, this paper studied field state investigation, field state experiment, development of leakage alarm system and verification experiments. Field states investigation at livestock companies(10 companies) in cheong-won location to deduce the problems of auto water machine is analyzed. The field state experiment is conducted at B livestock company in cheong won location. The field state experiment method is measured with leakage current when ELB tripped by environment factor(fine, cloudy, and rainy day). The LCDS is developed as MCU(Micro Control Unit) part applied leakage current values at B livestock company. Verification experiments for the leakage current detecting system were conducted by two methods of current supply and field test. Results show that LCDS suggested in this paper are valuable and usable in auto water machine based on environment factor, which will prevent severe damage to human beings and properties and reduce the electrical fires in livestock.

• 문화기술의 융합
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• 제10권2호
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• pp.525-530
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• 2024

환경정보를 실시간으로 획득하여 정보를 제공하는 환경 모니터링 시스템 필요성이 확대되고 있다. 특히 공공수역 수질관리의 경우 법적으로 수동측정과 자동측정을 통해 상시 관리를 진행해야 하며, 대기오염도 탄소중립 실현과 연관하여 미세먼지, 배기가스 저감을 위한 상시 측정 및 관리가 필요한 실정이다. 본 연구에서는 수질오염 및 대기오염 정보를 실시간으로 측정하여 모니터링을 할 수 있는 시스템을 구현하였다. 측정을 위한 도구로 육상과 수상을 동시에 이동 가능한 호버크래프트를 활용하였다. 호버크래프트 본체에 수질측정 및 대기오염측정 센서를 장착하고 그 정보를 실시간으로 모니터링 시스템으로 전송할 수 있는 통신 모듈을 장착하였다. 환경측정용 호버크래프트의 구조를 설계하였으며, 실시간 정보전달 통신 모듈로는 저전력 장거리 통신이 가능한 LoRa 모듈을 적용하였다. 실제 하드웨어 구현을 통해 제안한 시스템의 동작 성능을 확인하였다.

• 한국자동차공학회논문집
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• 제20권4호
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• pp.25-32
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• 2012

Cold start driving cycles exhibit an increases in friction losses due to the low temperatures of metal components and media compared to the normal operating engine conditions. These friction losses are adversely affected to fuel economy. Therefore, in recent years, various techniques for the improvement of fuel economy at cold start driving cycles have been introduced. The main techniques are the upward control of coolant temperature and the fast warm-up techniques. In particular, the fast warm-up techniques are implemented with the coolant flow-controlled water pump and the WHRS (waste heat recovery system). This paper deals with an effect of fast ATF (automatic transmission fluid) warm-up on fuel economy using a recovery system of EGR gas waste heat in a diesel engine. On a conventional diesel engine, two ATF coolers have been connected in series, i.e., an air-cooled ATF cooler is placed in front of the condenser of air conditioning system and a water-cooled one is embedded into the radiator header. However, the new system consists of only a water-cooled heat exchanger that has been changed into the integrated structure with an EGR cooler to have the engine coolant directly from the EGR cooler. The ATF cooler becomes the ATF warmer and cooler, i.e., it plays a role of an ATF warmer if the temperature of ATF is lower than that of coolant, and plays a role of an ATF cooler otherwise. Chassis dynamometer experiments demonstrated the fuel economy improvement of over 2.5% with rapid increase in the ATF temperature.

• Journal of Biosystems Engineering
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• 제23권6호
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• pp.599-606
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• 1998

This study was carried out to develop the control system with PLC and its operating software and to investigate its control ability of greenhouse environments. Two experimental greenhouses were controlled by PLC and ON/OFF controller, respectively. In greenhouse controlled by PLC, target values of air temperature, relative humidity and $CO_2$ concentration were automatically changed. In warm-water heating, the variation of air temperature was reduced to $\pm$ $0.6^{\circ}C$ by the method of proportional-integration(PI) control with an inverter. In ventilation, the variation of air temperature was reduced, since windows open and close with multistage by mutual relation formula among the target, indoor, and outdoor temperature. Relative humidity at daytime was maintained with range of 35% to 55% by PLC controlled fogger. $CO_2$ concentration was automatically controlled from 300 to 800 $\mu$molㆍ$mol^{-1}$ according to amount of solar radiation. The suppling amount and frequency of nutrient solution were controlled by total integrated solar radiation. Difference in the yield of cucumber in the greenhouse controlled by PLC and by ON/OFF controller was not significant at the 5% level.

• 한국환경과학회지
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• 제19권6호
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• pp.747-753
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• 2010

It follows in quality and sewage exclusion method of the investigation objective sector and the Combined Sewer Overflows which is suitable in regional characteristics and the confluence area against the rainfall initially a flow and the medulla and measurement - it analyzes the initial rainfall outflow possibility control plan which is suitable in the domestic actual condition and it proposes the monitor ring plan for the long-term flow and pollution load data accumulation. From the research which it sees the Infiltration water/Influent water and CSOs investigation it passes by the phase of hazard chain and Namwon right time 4 it does not hold reverse under selecting, Measurement it used the hazard automatic flow joint seal Sigma 910 machine and in case 15 minute interval of the I/I, it measured a flow at case 5, 15 minute standing of the CSOs. The water quality investigation for the water leakage investigation of the I/I and the sewage from the point which is identical with flow measurement during on-the-spot inspection duration against 6 items which include the BOD sampling and an analysis, when the rainfall analysis for CSOs fundamental investigation analyzed against 18 items which include the BOD sampling. Consequently, for the optimum interpretation invasion water / inflow water of the this investigation area day average the lowest flow - water quality assessment veterinarian optimum interpretation hazard average per day - lowest flow - it averages a medulla evaluation law department one lowest flow evaluation technique and it selects, it presentation collectively from here it gets, position result with base flow analysis of invasion water / inflow water.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.479-482
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• 2008

Since late of 2000, KIER has developed a novel pyrolysis process for production of fuel oils from polymer wastes. It could have been possible due to large-scale funding of the Resource Recycling R&D Center. The target was to develop an uncatalyzed, continuous and automatic process producing oils that can be used as a fuel for small-scale industrial boilers. The process development has proceeded in three stages bench-scale unit, pilot plant and demonstration plant. As a result, the demonstration plant having capacity of 3,000 tons/year has been constructed and is currently under test operation for optimization of operation conditions. The process consisted of four parts ; feeding system, cracking reactor, refining system and others. Raw materials were pretreated via shredding and classifying to remove minerals, water, etc. There were 3 kind of products, oils(80%), gas(15%), carbonic residue(5%). The main products i.e. oils were gasoline and diesel. The calorific value of gas has been found to be about 18,000kcal/$m^3$ which is similar to petroleum gas and shows that it could be used as a process fuel. Key technologies adopted in the process are 1) Recirculation of feed for rapid melting and enhancement of fluidity for automatic control of system, 2) Tubular reactor specially-designed for heavy heat flux and prevention of coking, 3)Recirculation of heavy fraction for prevention of wax formation, and 4) continuous removal & re-reaction of sludge for high yield of main product (oil) and minimization of residue. The advantages of the process are full automation, continuous operation, no requirement of catalyst, minimization of coking and sludge problems, maximizing the product(fuel oil) yield and purity, low initial investment and operation costs and environment- friendly process. In this presentation, background of pyrolysis technology development, the details of KIER pyrolysis process flow, key technologies and the performances of the process will be discussed in detail.