• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.209-212
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• 2013

Global warming and climate change is now an important issue in every industry. Construction is not an exception. Greenhouse Gases (GHG) are emitted by construction activities such as fuel usage in construction equipment and so on. In light of this, Intelligent Excavating System (IES), which is a robotic excavator with site modeling capability, is developed by a research consortium formed in Korea to improve productivity, quality, and safety of the traditional earthwork. This paper presents that energy saving effect of IES in comparison to traditional method. Through this review, we propose a research strategy to achieve carbon reduction goals in construction industry.

• 자원ㆍ환경경제연구
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• 제23권1호
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• pp.1-19
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• 2014

해상물류업에 기상기후정보의 이용은 자연재난으로 인한 리스크 감소, 정시도착, 고객으로부터 클레임 수 및 금액 감소, 화물파손 감소, 연료절감 등 다양한 효과를 기대할 수 있다. 기상기후정보 활용의 효율성을 표준화하는 데는 어려움이 있으나 Jeppesen사의 연료절감 성과를 적용하여 한국의 해상물류업에서 기상기후정보 활용의 경제적 성과를 VVOS의 성과를 기초로 분석한 결과, 2012년 기준으로 외항항해 국적선의 경우 약 622억 원의 연료 절감할 수 있었다. 그리고 내항항해의 경우, 연안의 풍속, 파고, 파주기 등이 화물운송에 큰 영향을 미친다고 할 수 있다. 내항운송에 악영향을 미치는 주요 기상요소는 풍속, 파고, 파주기라고 할 수 있는데, 선박 입출항실적과 기상요소와의 관계는 파고와 풍속과는 음의 관계를 파주기와는 양의 관계를 보이고 있어, 기상기후를 정확히 예측하면 입출항 실적을 제고할 수 있을 것으로 기대된다. 구체적으로, 고정효과모형에서 5% 유의수준 하에서 파고 1m 이상인 일수가 1일 증가하면 선박입출항 실적이 9.605천 톤이, 평균 풍속이 1m/s 증가하면 35.391천 톤이 감소하였다. 그리고 파주기 1초 증가하면 31.204천 톤의 실적이 중가하였다.

• 해양환경안전학회지
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• 제20권6호
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• pp.653-662
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• 2014

본 연구에서는 목포해양대학교의 실습선 새누리호를 대상으로 선박의 중앙집중 공조시스템에 공랭식 에어컨을 직접 설치하여 성능을 개선시킨 공기조화시스템으로 운전하였을 경우의 냉방 성능을 비교하고, 선실의 온열환경에 대한 실측조사를 통해서 향후 선박용 공기조화 설계 및 계획에 경험적 기초참고자료로 활용하고자 하는 것이다. 연구결과 동일한 외기조건에서 기존의 중앙집중방식 공조시스템과 개선된 공조시스템으로 운전하였을 경우, 모든 선실의 온도는 $24{\sim}28^{\circ}C$, 습도는 55~75 %로 쾌적한 조건임을 알 수 있었고, 발전기 부하를 측정결과 공기조화시스템의 성능개선에 따라 평균 부하 48 KW, 전부하시 부하율 약 8 %정도 감소하여 1일 연료소모량 FOC는 하루 평균 222[L/day]의 기름이 절약됨을 알 수 있었다. 또한 학생 선실(Cadet No. 21)은 기관실의 전열로 인해서 온도가 높게 나타났는데, 이것은 공기조화 설계 시 취출구 개수 및 전열부하를 고려하지 못한 결과로 판단된다.

• Journal of Biosystems Engineering
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• 제41권4호
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• pp.328-336
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• 2016

Purpose: The heat culture areas of greenhouses have been continuously increasing. In the face of international oil price fluctuations, development of energy saving technologies is becoming essential. To save energy, auxiliary heat source and thermal insulation technologies are being developed, but they lack cost-efficiency. The present study was conducted to save energy by developing a conceptually new semi-basement type greenhouse. Methods: A semi-basement type greenhouse, was designed and constructed in the form of a three quarter greenhouse as a basic structure, which is an advantageous structure to inflow sunlight. To evaluate the performance of the developed greenhouse, a similar structured general greenhouse was installed as a control plot, and heating tests were conducted under the same crop growth conditions. Results: Although shadows appeared during the winter in the semi-basement type greenhouse due to the underground drop, the results of crop growth tests indicated that there were no differences in crop growth and development between the semi-basement type greenhouse and the control greenhouse, indicating that the shadows did not affect the crop up to the height of the crop growing point. The amount of fuel used for heating from January to March was almost the same between the two greenhouses for tests. The heating load coefficients of the experimental greenhouses were calculated as $3.1kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the semi-basement type greenhouse and $2.9kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the control greenhouse. Since the value is lower than the double layer PE (polyethylene) film greenhouse value of $3.5kcal/m^2{\cdot}^{\circ}C{\cdot}h$ from a previous study, Tthe semi-basement type greenhouse seemed to have energy saving effects. Conclusions: The semi-basement type greenhouse could be operated with the same fuel consumption as general greenhouses, even though its underground portion resulted in a larger volume, indicating positive effects on energy saving and space utilization. It was identified that the heat losses could be reduced by installing a thermal curtain of multi-layered materials for heat insulation inside the greenhouse for the cultivation of horticultural products by installing thermal curtain of multi-layered materials for heat insulation inside the greenhouse, it was identified that the heat losses could be reduced.

• 오토저널
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• 제3권3호
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• pp.8-13
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• 1981

종래 자동차용 엔진유에 요구되었던 주요기능으로서는 마찰부위에서 발생되는 마찰저항이나 마 모를 감소시키는데에 국한하여 연구개발되어 왔었지만 12973년의 석유의기를 계기로 하여 이와 같은 기능외에도 소비에너지를 최소화 할려는 노력의 일환으로서 연비절약형의 엔진유는 물론 내구서어이 양호한 롱라이프(long life)유가 등장되었을뿐만 아니라 날로 심각해져가고 있는 자 동차배기가스에 의한 대기오염과도 적합성을 고겨한 새로운 기능의 엔진유가 개발됨에 따라 이와 관련하여 자동차엔지유를 통해본 연료비절감효과와 그 문제점을 검토해 보고자 한다.

• International Journal of Automotive Technology
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• 제4권1호
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• pp.1-8
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• 2003

Wastes such as shredder dust of disposed vehicles can be decomposed into low calorific flammable gases by Pyrolysis gasification. A stationary electric Power generation using an internal combustion engine fuelled with the waste-pyrolysis gas is an effective way to ease both waste management and energy saving issues. The waste-pyrolysis gas mainly consists of H$_2$, CO, $CO_2$ and $N_2$. The composition and heating value of the gas generated depend on the conversion process and the property of the initial waste. This research analyzed the characteristics of the combustion and the exhaust emissions in a premixed charge spark ignition engine fuelled with several kinds of model gases, which were selected to simulate the pyrolysis-gases of automobile shredder dusts. The influences of the heating value and composition of the fuel were analyzed parametrically. Furthermore, optical analyses of the combustion flame were made to study the influence of the fuel's inert gas on the flame propagation.

• 수산해양교육연구
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• 제7권1호
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• pp.31-43
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• 1995

For the fuel saving in the fish farm, the heat transfer performances of various tubes, XL-tube, copper-tube, copper-Nikel-tube and Al-brass-tube, were compared. The XL-tube, which is most commonly used for heating water, showed the poorest heater transfer performance, while the Al-Brass tube shows the best performance. As far as average temperature difference of four tubes concerns, XL-tube is $3.34^{\circ}C$, Copper tube is $10.34^{\circ}C$, Copper-Nikel tube is $11.3^{\circ}C$, Al-Brass-tube is $12^{\circ}C$, The best heat transfer performance of Al-Brass tube results from the enhancement of heat transfer coefficient caused by fin effect and good conductivity of the material.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.307-311
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• 2004

In this study, a novel hybrid vehicle is proposed. The vehicle has a flywheel-engine hybrid system. Flywheels are more effective as energy charge systems than electric batteries in a respect of output power density. However, transmissions to effectively drive flywheels are very complex systems such as CVTs (Continuously Variable Transmissions). In the proposed hybrid vehicle, Constant Pressure System is employed, which is hydraulic power transmission. Using Constant Pressure Systems, hydraulic CVTs are easily realized with variable displacement pumps/motors. In this paper, firstly, the proposed flywheel hybrid vehicle making use of Constant Pressure System is described. Secondly, fuel consumption characteristics of the flywheel hybrid vehicle are experimentally examined with the stationary test facility, which employs a flywheel as a load emulating vehicle inertia. Finally, the experimental results and discussions are described. Fuel consumption of 26km/L is expected for 10 mode driving schedule with vehicle mass of 1500kg.

• 한국자동차공학회논문집
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• 제21권4호
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• pp.120-127
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• 2013

Hybrid electric vehicles have applied electric parts for saving fuel consumption and reducing levels of environmental pollution. Electrification of automobiles is indispensable for entering into global market because of enhanced environment restriction. ISG (Integrated Starter & Generator) system is one of main electric parts and can improve fuel efficiency more than other components by using Idle Stop & Go function and regenerative braking system. However, if ISG motor and inverter work under the continuously high load condition, it will make them the decrease of performance and durability. So the ISG motor and inverter need to properly design the cooling system of them. In this study, we suggested the enhancement points by modifying the thermal design of ISG motor and then confirmed the improvement of the cooling performance.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.278-282
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• 2003

There is a strong industrial demands for the development of light-vehicle to improve fuel efficiency. It is more effective to reduce weight of the parts directly driven by an automobile engine. So the saving in weight of wheels which is operated by an automobile engine improve fuel efficiency more than other parts. There are many step of sheet metal forming in fabricating automotive wheel, so that it is difficult to design process and tools of multi-stage stamping. Traditionally, design process and tools have depended on the experience of skilled workers and it has done by trial and error methods. However, it needs too much costs and time. Taguchi methods has an advantage of the number of required experiments and reliability compared with trial and error method. In this study, Taguchi methods and response surface methods are applied to design process and tools of automotive wheel. As a result, the principal variables are selected and process conditions are optimized.