• Journal of Ginseng Research
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• 제3권2호
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• pp.156-167
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• 1979

Physiological characteristics of Panax ginseng were reviewed in relation to temperature. According to the old literatures and records of cultivator's experiences it was elucidated that ginseng plants require light but hate high temperature and that the cultural methods were developed to content two characteristics in contradiction. Low temperature (cool climate) during growing season seems (or ginseng to be essential and to escape from the extreme coldness according to air and soil temperature of natural habitat and cultivated area. Optimum temperature of dehiscence (15∼below 20$^{\circ}C$) is a little higher than that of germination (10∼15$^{\circ}C$). Optimum temperature for growing of new buds (18∼20$^{\circ}C$) is similar to that for growing after emergence (17∼21$^{\circ}C$). Dormancy of both matured embryo and new buds is broken at the same temperature (2∼3$^{\circ}C$). It seems reasonable that optimum temperature of photosynthesis (22$^{\circ}C$) is similar to that of growth. Respiration quotients of various organs or of whole plant ranged from 1.7 to 3 incrased with high temperature. Respiratory consumption and oxygen limitation seem to be potential factors to induce decay during dehiscence and germination of seeds and root rot in fields. Research on organ differentiation. photosynthesis, respiration and growth with age is needed for the development of cultivation methods.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.297-302
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• 2011

In this study, used Trnsys and will apply metropolitan city distinguishes, fixations and BIPV systems the photovoltaic module arrangement environment which receives solar radiation quantity plentifully from the case design process which and most the outcome value simulation did analyzed. The climate data uses each metropolitan city distinguishes 20 average weather data, With measured values of horizontal solar radiation. The error scope appeared with 0.1%~6.7%. Variable of module arrangement Azimuth and angle of inclination of module and comparison group Module on due south direction angle of inclination $45^{\circ}$ day time set with the yearly average solar radiation quantity which receives. The result When the case comparison group which arranges a solar storehouse module with optimum environment and comparing until the minimum 1.4% - maximum 10.9% the solar radiation quantity difference appears with the thing, metropolitan city distinguishes considers the case solar radiation quantity which will arrange a photovoltaic module and that must establish with optimum environment judges.

• 한국농림기상학회지
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• 제3권1호
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• pp.55-70
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• 2001

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

• 설비공학논문집
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• 제13권3호
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• pp.153-159
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• 2001

A system simulation program was developed for a multi-type inverter heat pump. Electronic expansion valve(EEV) was used to extend the capacity modulating range of the heat pump as expansion device. The program was also developed to calculate actual system performance with the building load variation with climate during a year. The performance variation of a multi-type hat pump with two EEV and an inverter compressor was simulated with compressor speed, capacity, and flow area of the EEV. As a result, the optimum operating frequency of the compressor and openings of the expansion device were decided at a given load. As compressor speed increased, he capacity of heat pump increased, the capacity of heat pump increased. Therefore flow area of EEV should be adjusted to have wide openness. Thus the coefficient of performance(COP) of the heat pump decreased due to increasement of compressor power input. The maximum COP point at a given load was decided according to the compressor speed. And under the given specific compressor speed and the load, the optimum openings point of EEV was also decided. Although the total load of indoor units was constant, the operating frequency increased as the fraction of load in a room increased. Finally ad the compressor power input increased, the coefficient of performance decreased.

• 현장농수산연구지
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• 제17권1호
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• pp.183-204
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• 2015

남태평양의 종주국이라고 할 수 있는 파푸아뉴기니의 기상환경은 고온다습한 열대우림기후로 작물의 생육에 아주 적합한 조건을 가지고 있어서 작물의 생산량을 증대시킬 수 있는 잠재력이 있는 천혜의 나라이다. 파푸아뉴기니 농촌 마을은 자급자족시대를 넘어 소득이 가능한 작물생산을 원하고 있다. 좋은 작물생산을 위하여 농업기상 환경을 이해하고 관수시설 설치 등 기술보급 등이 필요하다. 특히, 좋은 토양을 만들기 위하여 pH, EC, ORP 측정을 통한 개선이 필요하다. 농산물 시장은 급격히 현대화되고 있어 규격 생산, 소비자가 원하는 농산물 생산이 요구되고 있다. 파푸아뉴기니의 농업발전을 위하여 국제 기술협력이 요구되고 있는데 부존자원이 부족한 우리로서는 양국간 경제발전에 도움이 될 것이다. 특히, 파푸아뉴기니 농업개발을 위한 이 지역의 농업 기초 환경조사는 농업 기술협력의 큰 다리 역할을 하게 될 것으로 기대한다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.271-271
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• 2015

The Ecuadorian coast has two different climate regions. One is humid region where the annual rainfall is above 2000 mm and rain falls in almost all months of the year, and the other is dry region where the annual rainfall can fall below 50 mm and rainfall can be very seasonal. The agriculture is frequently limited by the seasons during the year and the availability of rainfall amounts. The corn fields in Ecuador are cultivated during the rainy season, due to this reason. The weather conditions for optimum development of corn growth require a monthly average rainfall of 120 mm to 140 mm and a temperature range of $22^{\circ}C{\sim}32^{\circ}C$ for the dry region, and a monthly average rainfall of 200 mm to 400 mm and a temperature range of $25^{\circ}C{\sim}30^{\circ}C$ for the humid area. The objective of this study is to predict how the weather conditions are going to change in corn fields of the coastal region of Ecuador in the future decades. For this purpose, this study selected six General Circulation Models (GCM) including BCC-CSM1-1, IPSL-CM5A-MR, MIROC5, MIROC-ESM, MIROC-ESM-CHEM, MRIC-CGC3 with different climate scenarios of the RCP 4.5, RCP 6.0, and RCP 8.5, and applied for the period from 2011 to 2100. The climate variables information was obtained from the INAMHI (National Institute of Meteorology and Hydrology) in Ecuador for the a base line period from 1986 to 2012. The results indicates that two regions would experience significant changes in rainfall and temperature compared to the historical data. In the case of temperature, an increment of $1^{\circ}C{\sim}1.2^{\circ}C$ in 2025s, $1.6^{\circ}C{\sim}2.2^{\circ}C$ in 2055s, $2.1^{\circ}C{\sim}3.5^{\circ}C$ in 2085s were obtained from the dry region while less increment were shown from the humid region with having an increment of $1^{\circ}C$ in 2025s, $1.4^{\circ}C{\sim}1.8^{\circ}C$ in 2055s, $1.9^{\circ}C{\sim}3.2^{\circ}C$ in 2085s. Significant changes in rainfall are also projected. The rainfall projections showed an increment of 8%~11% in 2025s, 21%~33% in 2055s, and 34%~70% in 2085s for the dry region, and an increment of 2%~10%, 14%~30% and 23%~57% in 2025s, 2055s and 2085s decade respectively for humid region.

• 한국자동차공학회논문집
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• 제16권2호
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• pp.150-157
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• 2008

The main objective of this paper is to investigate the performance characteristics of a $CO_2$ air conditioning system for fuel cell electric vehicles (FCEV). The present air conditioning system for FCEV uses the electrically driven compressor and electrically controlled expansion valve for $CO_2$ as a working fluid. The experimental work has been done with various operating conditions, which are quite matching the actual vehicle's driving conditions such as different compressor speed and high pressure to identify the characteristics of the system. Experimental results show that the cooling capacity and coefficient of performance (COP) were up to 6.3kW and 2.5, respectively. This paper also deals with the development of optimum high pressure control algorithm for the transcritical $CO_2$ cycle to achieve the maximum COP.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2013년도 제48차 하계학술발표논문집 21권2호
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• pp.423-426
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• 2013

본 연구에서는 임분 단위에서 산림의 이산화탄소 흡수 및 저장 기능을 최적화 할 수 있는 최적의 산림시업체계를 도출하고자하였고, 이를 위해 임분 생장모델과 Simulated Annealing 휴리스틱 기법을 적용하여 임분탄소 최적화 프로그램을 개발하였다. 휴리스틱 알고리즘에서 최적해를 찾기 위해 반복 실행 되는 과정에서 더 이상 최적해을 찾지 못하고 목표 값이 어떤 일정한 값(Local Optimum)에 계속 머무는 현상을 해결하기 위해 임계치를 적용하며, SA 휴리스틱 기법에서는 열균형테스트를 이용하고 있다. 개발된 프로그램을 이용하여 3가지 산림 시업 시나리오에 대한 비교 분석을 실시하기 위해 프로그램을 실행한 결과, 목재수확량의 경우 목재수확량을 최대를 목표로 한 대안이 3개 시나리오 가운데 목재수확량이 가장 높은 것으로 나타났으며, 또한 탄소저장량에서도 탄소저장량을 최적화한 대안이가 탄소저장량이 가장 높은 것으로 나타나 프로그램이 목적에 맞게 개발된 것으로 판단됐다. 또한 열균형 테스트의 온도저감율을 조정하여 프로그램을 반복실행하여 온도저감율이 프로그램 실행 시에 미치는 영향을 분석한 결과 온도저감율에 따라 출력되는 목적함수의 최적값과 프로그램 반복횟수가 영향을 받는 것으로 나타나 프로그램 실행을 최적으로 하기위해 온도 저감율의 파라미터 값을 0.1로 설정하였다.

• 한국조경학회지
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• 제27권5호
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• pp.38-47
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• 2000

Carbon dioxide is a major greenhouse gas causing climate change. This study quantified annual direct and indirect uptake of carbon by urban greenspace, and annual carbon release from vegetation maintenance and fossil fuel consumption. The study area was whole Chuncheon and Kangleung, and also two districts of Kangnam and Junglang in Seoul, cities located in middle Korea. Carbon uptake by urban greenspace played an important role through offsetting carbon release by 6-7% annually in Chuncheon and Kangleung. For Kangnam and Junglang, where the population density was relatively higher, urban greenspace annually offset carbon release by 1-2%. Future possible tree plantings could double annual carbon uptake by existing trees in urban lands (except natural and agricultural lands) of a study city. Based on study results, planning and management guidelines for urban greenspace were suggested to save energy and to reduce atmospheric $CO_2$ concentrations. They included selection of optimum tree species, proper planting location from buildings, design of multilayered planting, amendment of existing regulations for greenspace enlargement, avoidance f intensive vegetation maintenance, and conservation of natural vegetation.

• 설비공학논문집
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• 제26권8호
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• pp.375-380
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• 2014

The purpose of this paper is to investigate the cooling and heating performance of a standalone-type thermoelectric system equipped with a thermoelectric module. The system consists of a blower and two thermoelectric modules with a fin, which is soldered onto both sides of the thermoelectric module and a courtesy light. The thermoelectric system experiment is conducted with the intake voltage to find the optimum cooling and heating performance of each. The results showed that the cooling capacity and coefficient of performance (COP) were 22 W and 0.31, and the heating capacity and COP were 147 W and 1.1, respectively. In the vehicle cooling and heating performance test in a climate wind tunnel, the results showed that the standalone thermoelectric system's cooling performance was slightly better than the base system; and the heating performance of the standalone thermoelectric system was $54.1^{\circ}C$ and the COP was 1.3, compared to the base system.