• 한국농림기상학회지
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• 제5권2호
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• pp.70-80
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• 2003

본 연구에서는 KoFlux네트워크 타워 관측소의 하나인 광릉 낙엽 활엽수림에서 최초로 직접 관측된 이산화탄소 플럭스를 보고한다. 2002년 6월부터 8월까지 에디 공분산 시스템을 다른 기상 관측 기기들과 함께 30 m 타워에 설치하였다. 관측 장소가 계곡과 같은 경사지에 위치해 있음에도 불구하고 관측된 난류 특성이, 제한된 풍향(즉, 90$\pm$45$^{\circ}$)의 경우, 평평하고 균질한 이상적인 장소에서 관측된 것들과 크게 다르지 않았다. 관측 자료 회수율은 비록 낮았으나, 분석된 예비 결과는 고무적이고, 연구해야 할 가치가 있는 것으로 나타났다. 이류 항을 무시하면, 생태계의 순 $CO_2$ 교환(NEE)은 6월에서 8월까지 약 -1.2에서 0.7 mg m$^{-2}$ s$^{-1}$의 범위를 보였다. 약한 난류가 야간 NEE에 미치는 효과를 마찰 속도(u*)및 저류 항의 산출과 관련하여 살펴보았다. 낮은 u*가 NEE에 미치는 영향은 약 0.2 m s$^{-1}$의 문턱 값을 기점으로 뚜렷하게 나타났다. 야간 NEE에 미치는 저류 항의 역할은 거의 나타나지 않았는데, 이는 밤 동안 산림 내에 축적된 $CO_2$가 경사면을 따라 배수류로 빠져나갔기 때문인 것으로 사료된다. 이는 또한 저류 항을 한 높이에서만 관측된 농도 자료를 사용함으로 생긴 오차로 인한 인위적인 결과일 수도 있다. 쌍곡선 광 반응식을 적용한 결과, 관측된 NEE 변화의 80% 이상이 설명되어, 이 산림 지역의 $CO_2$ 교환이 주로 빛에 의해 조절됨을 보여주었다. 이러한 관계식은 계절에 걸쳐 빠진 자료를 채워 넣는 자료 처리 과정에 효과적으로 사용될 수 있다. 마지막으로, 선형류 모형에 근거한 간단한 규모 분석에 의하면, 이류항의 효과가 NEE산출에 큰 영향을 미칠 수 있는 것으로 나타났다.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.222-228
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• 2022

As a means to cope with the climate change crisis caused by global warming, automobile manufacturers continue to make efforts to use the driving energy of vehicles as electricity. As a result, parts industry such as battery, motor, and controller are attracting attention. China is often seen in large cities, with electric vehicles such as electric bicycles, electric motorcycles, and small electric vehicles popularized and commercialized, mainly in large cities. However, small electric vehicles are not popular in Korea, which is why the country's topography is high in hills. In order to drive the hilly domestic roads, power performance including vehicle climbing ability should be improved. In order to improve the power performance and the climbing capacity of small electric vehicles, the capacity of the motor should be increased. However, when the performance of the motor is improved, the weight of the motor becomes heavy and the price competitiveness is likely to decrease. In addition, in order to operate a high-performance motor, the power consumption of the battery is rapidly increased, so various problems must be solved. In order to commercialize a small electric vehicle for one or two people who do not emit harmful exhaust gas to the human body in a hilly domestic terrain, it is effective to have a separate transmission system. In this study, we were conducted dynamometer test to produce a continuously variable transmission(CVT) system prototype using a spring that can be applied to a small electric vehicle and to install a CVT system prototype manufactured in a small electric vehicle. The dynamometer test results showed that the maximum speed performance, acceleration performance, and climbing performance were improved.

• Macromolecular Research
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• 제11권2호
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• pp.73-79
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• 2003

Generally, field performance of elastomeric track pad components has been poor, especially for the medium to heavy tonnage tracked vehicles, which are operated on the hilly cross-country course. The service life of these track pad, is affected not only by the terrain and environmental conditions but also by the speed, cornering, braking, weight of the vehicle, and the track tread design. In this research, modulus, tearing energy, and the rate of crack propagation of vulcanizates are evaluated by changing base materials to improve the service time of track pad. By increasing the contents of carbon black, modulus, tearing energy, and fatigue crack growth resistance of vulcanizates improved. Compared with the NR vulcanizate, the HNBR vulcanizate had a higher value of tearing energy. The rate of crack propagation of vulcanizates using smaller size carbon black was slower than that using larger size carbon black. When the HNBR was blended with the ZSC, the tearing energy of the vulcanizates was a little reduced because of the high modulus but the crack propagation rate was reduced significantly. In the relation between the crack propagation rate and the strain energy release rate, though up to 100% strain were applied to specimens, the slope on the log scale ($\beta$) varied between 1.72 and 2.3 with the kind of elastomer.

• 대한지리학회지
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• 제40권
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• pp.15-29
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• 1989

특정지역의 지형은 지질적인 제여건을 반영하고 있으므로 지질과 지형과의 관계를 밝히는데는 다방면에 걸친 연구분석이 이루어져야 한다. 한국 남동지대에 발전하는 지질구조중 소증 양산절층, 동래절층 등의 지질구조는 그 지역의 구조운동을 밝히는 중요한 지표가 될 뿐아니라 지형발달에도 크게 영향을 미치고 있어 지형학적으로도 관심의 대상이 되고 있다. 본 연구의 목적은 태화강 유역의 경사와 절봉면을 분석함으로서 양산절층과 그 부근에 발달한 지질구조가 하천지형의 발달에 어떠한 영향을 미치고 있는가를 밝하는데 필요한 기초자료를 제공하려는 것이다.

• 상하수도학회지
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• 제23권2호
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• pp.223-230
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• 2009

Most urban water management systems are becoming vulnerable to flooding and drought due to the climate change (CC), urbanization and energy shortage. Despite of poor water management circumstances caused by extremely uneven annual rainfall and hilly terrain, traditionally we have made a sound and sustainable life based on our own philosophy and technologies which copes with our rigid environment. In this study a new paradigm of rainwater management is suggested and multipurpose and creative rainwater harvesting and management (RWHM) systems are introduced providing several case studies such as rainfall storage drainage (RSD) system, rainwater infiltration facilities and star city RWHM system. This new RWHM paradigm leads Seoul Metropolitan Government (SMG) in the Republic of Korea to change regulations and politics for the integrated RWHM. Finally, RWHM is expected to improve the safety, efficiency, energy consumption of urban water infrastructure, to reduce urban heat island phenomenon and, furthermore, to contribute in finding solutions for worldwide water issues and to adapt CC.

• 한국농촌건축학회논문집
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• 제21권3호
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• pp.41-48
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• 2019

The purpose of this study is to understand whether the architecture of the mountain village conforms to the geography and local landscape, and become a unique scenic element. Also, the study is to grasp the status of the village landscape design elements. The methods and contents of the study were surveyed by field research with references in Biederbach community, an isolated mountain village in Southwestern Germany. The time frame for the survey research is July 2015. The contents of the study include the analysis of the village's landscape structure, architecture, and landscape design patterns. The following conclusions were reached through the above research process. First, the village landscape structure seen in the mid-distance view is the hilly scene of the alpine region, which houses the sloping terrain of Black Forest and surrounds the residential area with the grassland covered by the Black Forest. Second, the main elements of the town's landscape building are historical culture, traditional architecture, topology and nature, and artificial environmental design. Third, the landscape design utilizing the village's resources creates a sustainable community's residential environment.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.206-214
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• 2022

Automobile manufacturers in each country are spurring the development of electric vehicles that use electric energy, an eco-friendly energy, as a futuristic vehicle. Electric vehicles have the advantage of no harmful gas or environmental pollution and low noise. Unlike automobiles using existing internal combustion engines using fossil fuels, electric vehicles use the electricity of batteries to cause rotational motion of motors. In the electric vehicle driven by the motor, it is indispensable to develop a controller for controlling the motor. One of the areas where automobile manufacturers are concentrating is the development of small electric vehicles as a personal transportation means. Small electric vehicles such as electric motorcycles, one-seat electric vehicles and two-seat electric vehicles are expanding the market as a means of operating throughout the city. In the domestic road conditions with many hills, it is effective to have a separate transmission system for small electric vehicles to drive smoothly. In this study, we propose a new type of continuously variable transmission(CVT) system to ensure that small electric vehicles can be driven smoothly in hilly domestic terrain. The proposed CVT system is equipped with a basic disk and a rotational disk in the driving pulley and the driven pulley, respectively, and is applied with a sloping spline to rotate the rotational disk. To commercialize the proposed CVT system, an experimental device was developed to examine the power transmission efficiency and the configuration of the CVT system was proposed.

• International journal of advanced smart convergence
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• 제11권1호
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• pp.87-93
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• 2022

In each country, efforts are being made to replace engine-driven cars and motorcycles using fossil fuels with electric drive. Electrically driven vehicles have the advantage of no harmful gas or environmental pollution and low noise. In the motorcycle market, China accounts for more than 95% of the world, and the electric motorcycle market is being revitalized due to the strengthening of regulations. Japan is actively preparing to include electric motorcycles in ISO 26262, forming a TF team centered on electric motorcycle producers. Therefore, it is necessary to respond to standardization targeting China and Japan in Korea. In this study, we propose a proprietary transmission model that can be applied to small electric vehicles that can be operated in hilly domestic terrain. The proposed continuously variable transmission model is a continuously variable transmission system which moves the pin between the basic disk and the rotary disk using a spline to perform shifting. The proposed continuously variable transmission model is used in the pulley configuration by connecting the linear type spline and the inclined spline with the central axis of the basic disk and the rotational disk, respectively. In addition, it can be divided into two types according to the application of the auxiliary disk, and the production drawing is completed for the practical use of the model.

• 한국농림기상학회지
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• 제5권4호
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• pp.261-265
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• 2003

복잡지형상의 일 최저기온 공간내삽 과정에서 유용한 설명변수로 등장한 찬 공기 유입량은 적용면적, 즉 공간규모에 따라 그 값이 크게 변하므로, 지형기후학적 최저기온 내삽모형의 실용화를 위해서는 최적규모를 파악해야 한다. 본 연구에서는 동질적인 중규모 기후구역을 대표하는 기준 관측값에 대한, 같은 구역 내 여러 지점의 기온편차를 계산하고, 이를 다양한 반경의 주변지역 찬 공기 유입량에 회귀시켜 일 최저기온에 미치는 지형의 최적 영향권을 도출하고자 하였다. 경남 하동의 배 과원지대에 1 ${\times}$ 1 km 구역을 설정하고 8개 지점에서 2002년 9월부터 2003년 2월까지 10분 간격으로 기온을 측정하였다. 동일 구역 내 기상청 자동기상관측자료를 기준으로 삼아 복사냉각일의 최저기온 편차를 8개 지점별로 얻었다. 연구지역의 고도를 10 m 해상도의 수치고도모형으로 표현하고 이를 토대로 8개 지점의 냉기 유입량을 계산하였다. 이 때 10 m 단위로 100 m까지 반경을 증가시키면서 유입량의 평활화 평균값을 계산하여 최저기온 편차를 회귀시켰다. 그 결과 복사냉각일의 국지적인 최저기온 결정에는 반경 50 m 범위 (약 1 ha) 주변지역 지형이 가장 유효함을 알 수 있었다.

• 한국산림과학회지
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• 제83권3호
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• pp.299-310
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• 1994

본 연구는 강원도 춘천군에 위치한 임업진흥촉진지역(林業振興促進地域)을 대상으로 총수확비용(總收穫費用)(임도개설비(林道開設費)+집재비(集材費))을 최소화하는 양방향(兩方向)-단계집재(段階集材) 및 이단계집재(二段階集材)를 위한 적정임도간격(適正林道間隔) 및 임도밀도(林道密度)를 산출하였다. 이때의 임도개설비(林道開設費)는 km당 천만원부터 6천만원까지이다. 그 결과는 다음과 같다. 양방향(兩方向)-단계집재(段階集材)에서는 케이블 크fp인이 적합하며, 적정임도간격(適正林道間隔)은 1,698m~4,192m,평균 3,087m이며, 임도밀도(林道密度)는 3.44m/ha~8.44m/ha, 평균 5.12m/ha로 산출되었다. 양방향(兩方向)-이단계집재(二段階集材)에서 중지형(中地形)은 중형집재기와 로깅부기의 조합기종이 적합하며 임도간격(林道間隔) 1,483m~3,481m, 평균 2,589m로서, 임도밀도(林道密度)는 4.05m/ha~9.46m/ha, 평균 5.90m/ha로 산출되었다. 또한 급지형(急地形)은 중형집재기와 진성윈치의 조합기종이 적합하며, 임도간격(林道間隔) 1,693m~3,982m, 평균 2,960m로서, 임도밀도(林道密度)는 3.68m/ha~8.64m/ha 평균 5.38m/ha로 산출되었다.