• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.250-250
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• 2016

인공위성을 이용한 강수관측은 전 지구적 규모에서 시공간적으로 균일한 강수정보를 지속적으로 제공할 수 있으며, 가뭄에 중요한 하나의 변수로서 가뭄정보를 제공할 수 있다는 장점이 있어 점차적으로 미계측지역 수문학적으로 활용성이 증대되고 있다. 그러나 인공위성 기반 강수관측자료는 지상관측 강우자료에 비해 시 공간해상도가 낮고, 관측 당시의 대기 상태, 관측기기, 시 공간적 대표성 문제 등에서 기인한 많은 불확실성을 포함하고 있다. 이러한 불확실성을 보완하기 위한 목적으로 미국 항공우주국 (National Aeronautics and Space Administration: NASA)는 GPM(Global Precipitation Measurement) 위성을 핵심위성으로 한 다중 위성자료를 이용하여 전지구적으로 30분 간격, 10 km 해상도의 GPM IMERG (Integrated Multi-satellitE Retrievals for GPM)를 생산 제공하고 있다. 본 연구에서는 다중 인공위성 추정 강수의 가뭄 활용성을 검토하기 위한 목적으로 GPM IMERG 위성 강우 자료(Early run, Late run, Final run)의 검증 및 평가를 수행하고자 하였으며, 각각의 자료들을 강수사례에 적용하여 10 km, 30분 해상도를 가지는 1.5km CAPPI (Constant Altitude Plan Position Indicator) 레이더 및 지상 강우자료와 비교 검증하였다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.173-173
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• 2017

드론의 시장규모가 커짐에 따라 초창기 군사 목적에서 현재 민간부문으로 확대되고 있다. 현재 드론은 실외에서 사용될 목적으로 제작된 것이 많으나 실내에서도 드론의 활용 여부가 증가할 것으로 예상된다. 본 연구에서는 실외에서만 사용 가능한 GPS를 대신하여 영상 촬영으로 획득한 이미지를 CNN으로 학습을 시켜 자율고도제어비행을 하도록 한다. 첫 번째로 수동 조작하는 드론에 IMU센서를 부착하여 획득한 고도 데이터를 표로 제시함으로써 GPS를 사용하지 않는 드론의 실내주행에서 일정한 고도 유지는 다소 무리가 있음을 보여준다. 두 번째로 드론의 수동 조작은 일정하지 않은 고도 때문에 CNN의 학습할 영상 획득이 어렵다. 일정한 고도의 영상 획득을 위한 실험용 높이 조절 Base를 제작하여 고도별 영상을 획득한다. 획득한 영상을 통해 얻은 이미지를 CNN 학습을 시킨 후, 학습에 사용되지 않은 이미지를 사용하여 고도 판별을 확인한다. 대조군으로 실내장소를 바꾸어 미리 학습된 CNN으로 고도 판별을 확인한다. 학습에 사용된 이미지의 환경(생명공학관)과 대조군(제 2 공학관)이 촬영된 장소의 환경요소의 차이로 오차가 발생한다. 오차는 실내 장소의 총 높이의 차이 및 서로 상이한 천장 구조물에 따른 것으로 사료되며 Data crop을 통해 획득한 이미지의 천정 부분을 제거하여 노이즈를 줄여 고도 판별의 정확도를 높일 수 있을 것으로 예상한다. 세 번째, CNN으로 학습을 통해 Model을 도출하여 자율 고도 제어 프로세스를 제시한다. 그리고 해당 프로세스를 이용한 자율고도제어 주행과 수동조작을 통한 주행에서의 Z축 가속도 데이터의 표준편차를 비교하여 본 연구의 실효성을 보여준다

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.828-834
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• 2013

In this paper, TMC (Tracker Motion Controller) as one of the many research methods for condensing efficiency improvements can be condensed into efficient solar system configuration to improve the power generation efficiency of the castle with Concentrated solar silicon and photovoltaic systems (CPV)experiments using PV systems. Microprocessor used on the solar system, tracing the development of solar altitude and latitude of each is calculated in real time. Also accept the value from the sensor, motor control and communication with the central control system by calculating the value of the current position of the sun, there is a growing burden on the applicability. Through the way the program is appropriate for solar power systems and sensors hybrid-type algorithm was implemented in the ARM core with built-in TMC, Concentrated CPV system compared to the existing PV systems, through the implementation of the TMC in the country's power generation efficiency compared and analyzed. Sensor method using existing experimental results Concentrated solar power systems to communicate the value of GPS location tracking method hybrid solar horizons in the coordinate system of the sun's azimuth and elevation angles calculated by the program in the calculations of astronomy through experimental resultslook clear day at high solar irradiation were shown to have a large difference. Stopped after a certain period of time, the sun appears in the blind spot of the sensor, the sensor error that can occur from climate change, however, do not have a cloudy and clear day solar radiation sensor does not keep track of the position of the sun, rather than the sensor of excellence could be found. It is expected that research is constantly needed for the system with ongoing research for development of solar cell efficiency increases to reduce the production cost of power generation, high efficiency condensing type according to the change of climate with the optimal development of the ability TMC.

• Korean Journal of Remote Sensing
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• v.12 no.1
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• pp.1-16
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• 1996

Korea Aerospace Research Institute(KARI) is developing a Korea Multi-Purpose Satellite I(KOMPSAT-I) which accommodates Electro-Optical Camera(EOC), Ocean Color Imager(OCI), Space Physics Sensor(SPS) for cartography, ocean color monitoring, and space environment monitoring respectively. The satellite has the weight of about 500 kg and is operated on the sun synchronized orbit with the altitude of 685km, the orbit period of 98 minutes, and the orbit revisit time of 28days. The satellite will be launched in the third quarter of 1999 and its lifetime is more than 3 years. EOC has cartography mission to provide images for the production of scale maps, including digital elevation models, of Korea from a remote earth view in the KOMPSAT orbit. EOC collects panchromatic imagery with the ground sample distance(GSD) of 6.6m and the swath width of 15km at nadir through the visible spectral band of 510-730 nm. EOC scans the ground track of 800km per orbit by push-broom and body pointed method. OCI mission is worldwide ocean color monitoring for the study of biological oceanography. OCI is a multispectral imager generating 6 color ocean images with and <1km GSD by whisk-broom scanning method. OCI is designed to provide on-orbit spectral band selectability in the spectral range from 400nm to 900nm. The color images are collected through 6 primary spectral bands centered at 443, 490, 510, 555, 670, 865nm or 6 spectral bands selected in the spectral range via ground commands after launch. SPS consists of High Energy Particle Detector(HEPD) and Ionosphere Measurement Sensor(IMS). HEPD has mission to characterize the low altitude high energy particle environment and to study the effects of radiation environment on microelectronics. IMS measures densities and temperature of electrons in the ionosphere and monitors the ionospheric irregularities in KOMPSAT orbit.

• Atmosphere
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• v.34 no.2
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• pp.203-216
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• 2024

The National Institute of Meteorological Sciences in Korea has developed the Weather Modification Hybrid Rocket (WMHR), an advanced system that offers enhanced stability and cost-effectiveness over conventional solid-fuel rockets. Designed for precise operation, the WMHR enables accurate control over the ejection altitude of pyrotechnics by modulating the quantity of oxidizer, facilitating specific cloud seeding at various atmospheric layers. Furthermore, the rate of descent for pyrotechnic devices can be adjusted by modifying parachute sizes, allowing for controlled dispersion time and concentration of seeding agents. The rocket's configuration also supports adjustments in the pyrotechnic device's capacity, permitting tailored seeding agent deployment. This innovation reflects significant technical progression and collaborations with local manufacturers, in addition to efforts to secure testing sites and address hybrid rocket production challenges. Notable outcomes of this project include the creation of a national framework for weather modification technology utilizing hybrid rockets, enhanced cloud seeding methods, and the potential for broader meteorological application of hybrid rockets beyond precipitation augmentation. An illustrative case study confirmed the WMHR's operational effectiveness, although the impact on cloud seeding was limited by unfavorable weather conditions. This experience has provided valuable insights and affirmed the system's potential for varied uses, such as weather modification and deploying high-altitude meteorological sensors. Nevertheless, the expansion of civilian weather rocket experiments in Korea faces challenges due to inadequate infrastructure and regulatory limitations, underscoring the urgent need for advancements in these areas.

• The Korean Journal of Quaternary Research
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• v.19 no.1
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• pp.27-40
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• 2005

Researches onmarine terrace in Korea have been drastically progressed during the last two decades.main themes of researches include vertical and horizontal distribution of paleo-shoreline, sedimentary facies ofmarine terrace deposits, OSL dating of terrace deposits and estimation of uplift rate. At present, it is noted thatmarine terraces distributed at the same altitude do not always show the same sedimentary facies, nor have the same ages.marine terraces are generally divided into five terrace systems, of which ages increase in ascending order. There are some arguments about discrimination between 2nd and 3rd terrace systems and their age. The core discrepancy lies on the question of whether the level of the last interglacial terrace is on the level of about 20m or on the 30~35m(~40m) in altitude. The uplift rate based on the paleoshoreline distribution ranges between 0.10 and 0.20m/ka.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.333-339
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• 1996

The root and stem bark of Eleutherococcus spp. is used for the treatment of paralysis, rheumatism, arthritis, diabetes, stamina failure, high blood pressure, etc. This study was con­ducted to identify botanical origins and to select standard variety of Eleutherococcus spp. with analyzing eleutheroside E content(%) of root bark and that of Eleutherococcus senticosus at different collected area, time, part and grown area. The content of eleutheroside E in the root bark was determined by HPLC, and it was 0.1925% in Eleutherococcus senticosus, 0.1103% in E. chiisanensis, 0.0348% in E. koreanum and 0.0236% in E. sieboldianum. In seasonal change of eleutheroside E content, it was higher in autumn product than summer product in Eleutherococcus senticosus. It also was higher in root bark than stem bark in different part. To investigate eleutheroside E content of root bark among different collected local area in E. sen­ticosus, it was high order to Mt. Deokyu, Hokkaido and Mt. Seolak as a 0.1625%. 0.0493% and 0.027 %, respectively. The growth of Eleutherococcus senticosus was good at grown Unbong (altitude 10m), but eleu­theroside E content was high at grown Nogodan (altitude 1, 450m).

• The Journal of Dong Guk Oriental Medicine
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• v.5
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• pp.281-306
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• 1996

A study on the effect of the Sun-Moon-Stars(日月星辰) in Huang Ti Nei Ching("黃帝內經") on the formation of the Yunqi theory(運氣理論) have revealed following conclusions. 1. There was a record of Stars(星辰) written by Gabgol-Character(甲骨文字) in the Yin(殷) Dynasty. But the very first documentary records of Stars(星辰) is Shu Jing("書經"). Ancient astronomy had the tendency of astrology of combined with theory of the Five Elements(五行) and finally effects the theory of formation of Huang Ti Nei Ching("黃帝內經"). 2. Shu Jing("書經") said that Junrak(錢樂) made an Armillary sphere(運天儀) in the Sung(宋) Dynasty. And in the Jin(秦) and the Han(漢) Dynasty, they already observed the stars. The Sunkiokhyung(璿機玉衡) which is machinery of star-observing, became to be called an Armillary sphere (運天儀) by the pass of times. 3. As of the theory of the Cosmos-structure(宇宙-構造論) in Ohanunhangdaeron("五運行大論"), Guiyugu(鬼兒區) announced the Hypothesis of Covering Heaven(蓋天說) but Kibak(岐伯) supported the Hypothesis of chaosheven's(蓋天說) and in the theory of atmosphere(大氣論) in Ohanunhangdaeron("五運行大論") said that the earth was in Great Empty(太虛) and it was floating in the universe by the Great Chi(大氣). 4. The knowledge about the Five stars(五星) in Huang Ti Nei Ching("黃帝內經") is presented in the section of Gemgwejineonron("金?眞言論"), Gigoupyondaeron("氣交變大論"), Youkwonjeonggidaeron("六元正紀大論").ln the method of identifying the Five stars(五星) presented the criteria of the brightness, the altitude, the colours and the orbit etc. 5. The jupiter which has twelve year's revolution cycle was the basis of determination on the Twelve constellation(12辰), the Twelve field of heaven(12次), the Twelve Houses in the ecliptic(黃道 12宮), the Twelve Earth's Branches(12支) and the Twelve fields of Earth(12分野) and also it became the origin of the duodecimals(12進法). 6. The saturn having about twenty-eight year's revolution cycle became the criterion in identifying the Twenty Eight Constellations(28宿) which was used as the coordinates of the Celestial sphere (天球). 7. By the Percussional movement(歲差運動), the position of polaris and the Vernal-Antumal equinox(春秋分点) were shifted. Therefore the ancient the Heaven Gate-Earth Door(天門-地戶) changed from the position of Sil-Byuk(室壁), Yik-Jin(翼軫). And the precisional movements brought about the concept of the WunHoyYunSe(元會運世) that is a method of dividing a period. Also the precisional movement gave three dimension(三次元) foundation interpreted the Sixty JiaZi (六十甲子) which is revolving through sixty years uniformally. 8. The Hypothesis of the Nine Houses and Eight Winds(九宮八風論) which is one field of the astrology of ancient polaris-nine Houses divination plate(太一九宮占盤) brought about the concept of deficiency and excess and the concept of the Wind Vice(風邪). In the Calendar System(曆法) presented in Huang Ti Nei Ching("黃帝內經") the tropical year of the Sun-Moon-Stars(日月星辰) and the revolution and the rotation of the earth give explanations the changes of Yin-Yang(陰陽) by the use of the ten Celestial branches(十干) and the twelve Earth branches(十二支).

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.11
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• pp.180-187
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• 2013

The dinger in solar generation is the amount of sunlight which the solar cells absorb. Various types of solar trackers, which rotate themselves in order to make the solar cells face the sun as much as possible, have been developed, and especially the method of tracking with two axes has greatly contributed in increasing the generation amount at work sites. Among theses 2-axis solar trackers, the inclination-dependent 2-axis solar tracker are widely utilized for its advantages of requiring less initial investment and easy maintenance due to a solid structure. However, the drawback is that the generation efficiency is relatively low because of the structural restriction that limits the rotation angle, thus making it less efficient when tracking the sun. This paper proposes a method to increase the generation efficiency of the inclination-dependent 2-axis solar tracker. It also contains the derived equations needed for precise controlling along with a method to keep tracking with the other axis even when one has reached its angle limit. To confirm that the proposed method increases the amount of incidence onto the solar cells, formulas needed for operation on the proposed method and tracking the exact position of the sun are derived, and applying this to the quarterly data of Korea Astronomy and Space Science Institute it shows maximum over 11.1% more incidence compared to existing methods.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.696-704
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• 2010

The objective of this study was analysis of two methods of land suitability classification for wild edible green. One method was Maximum limiting factor method (MLFM) and the other was Multi-regression method (MRM) for land suitability classification for wild edible green. The investigation was carried out in Pyeongchang, Hongcheong, Hoeingseong, and Yanggu regions in Korea. The obtained results showed that factors related to the decision classification of the land suitability for wild edible green cultivation were land slope, altitude, soil morphology and gravel contents so on. The classification of the best suitability soil for wild edible greens were fine loamy (silty), valley or fan of soil morphology, well drainage class, B-slope (2~7%), available soil depth deeper than 100cm, and altitude higher than 501m. Contribution of soil that influence to crop yields using Multi-regression method were slope 0.30, altitude 0.22, soil morphology 0.13, drainage classes 0.09, available soil depth 0.07, and soil texture 0.01 orders. Using MLFM, area of best suitable land was 0.2%, suitable soil 15.0%, possible soil 16.7%, and low productive soil 68.0% in Hongcheon region of Gangwon province. But, area of best suitable land was 35.1%, suitable soil 30.7%, possible soil 10.3%, and low productive soil 23.9% by MRM. There was big difference of suitable soil area between two methods (MLFM and MRM). When decision classificatin of the land suitability for wild edible green cultivation should consider enough analysis methods. Furthermore, to establishment of land suitability classification for crop would be better use MRM than MLFM.