• Journal of Biosystems Engineering
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• 제25권6호
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• pp.457-462
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• 2000

Boom sprayers have been known by their excellency in field efficiency worker’s safety and pest control efficacy. The boom sprayer in Korea that was developed for paddy field is not suitable for upland field of which shape is irregular and inclination is steep, due to heavy chemical tank long boom width and manual on-off control of spraying. The goal of the study was to develope a boom control system that could control boom angles of left and right boom automatically and independently corresponding to local field slope. The prime mover was selected as a cultivating tractor. Main results of this study were as follows. 1. Ultrasonic sensor whose response time was 0.1s and response angle was within $\pm$20$^{\circ}$was selected to measure distance. Voltage output of the sensor(X, Volt) had a highly significant linear relationship with the vertical distance between the sensor and ground surface(Y, mm) as follows; Y=0.0036X-0.437 2. Left and right section of the boom could be folded up by a position control device(on-off control) which could control the left and right boom independently corresponding to local slope by equalizing distances between the sensor and boom at the center and left/right boom. Most reliable DB(dead band) was experimentally selected to be 75$\Omega$(6cm). 3. At traveling velocity of 0.3~0.5m/s RMS of error between desired and achieved height was less than 4.5cm The developed boom angle controller and boom linkage system were evaluated to be successful in achieving the height control accuracy target of $\pm$10cm.

• Journal of Forest and Environmental Science
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• 제38권4호
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• pp.239-248
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• 2022

Forestry crane work in a forest harvester or forwarder is regarded as one of most hard work requiring a very high level of operation skill. The operator must handle two or more multi-axes joysticks simultaneously to control the multiple manipulators for maneuvering the crane-tip to its intended location. This study has been carried out to develop a crane-tip controller which can intuitively maneuver the crane-tip, resulting in improving the productivity by decreasing the technical difficulty of control as well as reducing the workload. The crane-tip controller consists of a single 2-axis joystick and a control algorithm run on microcontroller. Lab-scale forestry crane was constructed using electric cylinders. The crane-tip control algorithm has the crane-tip follow the waypoints generated on the given path considering the dead band region using LBO (Lateral Boundary Offset). A speed control gain to change the speed of relevant cylinders relatively is applied as well. By the P (Proportional) control within the control interval of 20 msec, the average error of crane-tip control on the predefined straight path turned out to be 14.5 mm in all directions. When the joystick is used the waypoints are generated in real time by the direction signal from the joystick. In this case, the average error of path control was 12.4 mm for straight up, straight forward and straight down movements successively at a certain constant speed setting. In the slant movement of crane-tip by controlling two axes of joystick simultaneously, the movement of crane-tip was controlled in the average error of 15.9 mm when the crane-tip is moved up and down while moving toward forward direction. It concluded that the crane-tip control was possible using the control algorithm developed in this study.

• 농약과학회지
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• 제15권2호
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• pp.166-176
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• 2011

제주도의 녹차 밭에 서식하는 딱정벌레목인 청동풍뎅이 (Anomala albopilosa)의 사체와 녹차 밭 토양에서 분리한 Bacillus thuringiensis CAB530 균주의 생물효과를 검토하였다. 이 균주는 몇 종류의 해충에 대한 살충활성에서 난방제 농업해충 가운데 하나인 파밤나방에 높은 효과를 나타냈다. 파밤나방 2령 유충에 대한 살충활성 검정에서 CAB530 균주는 $LC_{50}$값이 $1.49{\times}10^4$(cfu/$m{\ell}$)으로 고활성을 보였다. 이 균주가 생산하는 살충성 독소단백질의 SDS-PAGE에서는 파밤나방에 살충활성이 있는 기존의 B. thuringiensis subsp. kurstaki와 비슷한 130kDa의 밴드를 나타내었다. 또한 파밤나방 중장액으로 반응을 시킨 후에 약 65kDa의 활성 독성단백질을 확인할 수 있었다 PCR수행에서 CAB530 균주는 cry1Aa, cry1Ab, cry1C, cry1D, cry1F 그리고 cry1I등 6 개의 유전자가 존재하는 것으로 밝혀졌으며, B. thuringiensis subsp. kurstala기준 균주와 차이가 있었다. 딱정벌레목에서 분리 선발한 B. thuringiensis CAB530균주는 crystal의 형태와 SDS-PAGE의 결과는 B. thuringiensis subsp. kurstaki와 유사하게 나타났지만, 살충활성 검정과 PCR product 전기영동 결과는 B thuringiensis subsp. aizawai와 유사하게 나타났다.

• 한국산림과학회지
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• 제111권2호
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• pp.287-301
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• 2022

본 연구는 기계화 목재 생산 작업에 가장 많이 활용되는 크레인 작업의 효율성을 높이기 위하여 엔드이펙터를 직관적으로 수직 또는 수평 제어할 수 있는 크레인 팁 제어방법을 제안하고 제어성능을 확인하기 위해 수행되었다. 실험 변수에 따른 제어성능을 검증하고자 전동실린더를 이용하여 실험실 규모의 크레인을 제작하고, 크레인에 대한 순기구학/역기구학 분석을 통하여 현재 크레인 팁의 위치좌표와 각 목표점에서의 조인트 각도를 출력할 수 있도록 구성하였다. 경로점을 생성하여 제어하는 방법을 이용하였고, LBO(Lateral Boundary Offset)을 이용한 불감대 영역을 설정하도록 하였다. 뱅뱅제어(Bang-bang control)을 이용하여 적정 파라미터를 선정하였고, 경로점의 개수와 LBO 반경은 평균오차와 관계가 있었으며, 실린더의 속도는 소요시간과 관계가 있는 것으로 확인되었다. 경로점의 개수가 증가, LBO 반경이 감소함에 따라 평균오차는 감소하였고, 실린더의 속도가 감소함에 따라 소요시간은 감소하였다. 비례제어를 이용하여 실린더의 속도가 매 제어주기마다 변경될 때에는 소요시간은 큰 폭으로 감소하였지만 실제 제어의 형상은 큰 범위에서 오버슈트와 언더슈트를 반복하며 제어가 이루어졌다. 따라서, 추가적으로 각각의 실린더의 속도를 상대적으로 변경할 수 있는 속도 게인을 적용하여 비례제어를 수행하였고, 10 mm 이내의 범위에서 제어가 이루어짐에 따라 20 ms의 제어주기에서 속도 게인이 적용된 비례제어만을 이용하여 크레인 팁 제어가 가능한 것으로 검증되었다.

• 지구물리와물리탐사
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• 제8권2호
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• pp.145-155
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• 2005

경상북도 포항시 흥해읍 일대에서 지열자원 개발을 위한 심부 파쇄대 탐지를 목적으로 수행된 자기지전류 (MT) 탐사에서 경북 안동과 충북 청원시의 대청호 및 일본의 Kyushu에 원거리 기준점을 설치하고 이를 이용한 자료처리 결과의 상호 비교를 통하여 원거리 기준점에 따른 겉보기 비저항과 위상 자료의 질을 검토하였다. 대상지역에서 약 165 km떨어진 대청호 자료를 이용한 경우는 전력주파수인 60 Hz대역과 자연 전자기장 신호가 미약한 $10^{-1}Hz\~1\;Hz$ 대역을 제외한 주파수 대역에서 매우 좋은 자료를 얻을 수 있었으며, 약 480 km 떨어진 Kyushu 원거리 기준점 자료를 이용해서 거의 모든 주파수 대역에서 연속성이 매우 좋은 전기비저항과 위상 곡선을 얻을 수 있었다. 이를 이용하여 2차원 역산을 수행한 결과, 지표의 10ohm-m 이내의 전기비저항을 보이는 반고결 이암층은 대상지역의 남쪽에서는 약 500 m 이상, 북쪽에서는 200 m 이내의 두께로 분포하며 북에서 남으로 경사진 형태로 나타났다. 심도 $500\~1,500m$에서 저비저항(L-2)과 고비저항(H-2)의 경계면은 단층면으로 해석되며 측점 206, 112와 414를 지나는 대략 $N15^{\circ}E$의 주향을 보인다. 1 km 이내의 천부의 저비저항 이상(L-4)은 파쇄대로 해석되며 측점 105를 지나면서 데략 $N60^{\circ}W$의 주향을 보인다. 또한, 북쪽의 큰 하천을 따라 저비저항 이상대가 공통적으로 나타나 구조선일 가능성을 시사한다. 그리고, 대상지역의 서쪽과 서남쪽의 $2\~3km$ 하부에서 10 ohm-m이내의 저비저항 이상대(L-3)가 나타나는데 이 층에 대해서는 향후 추가적인 연구가 요구된다.

• 복식
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• 제5권
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• pp.41-63
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• 1981

The mural portraits of the ancient Dukheungri tombs are very important for the study of our traditional costume because the tomb contains a stone. with the in-scription of the date of its erection, 408 A.D. and the name, and official status of the buried. The costumes shown in the mural paintings will be the basis on which historical research can be made concerning costumes before and after 400 A. D. The costume in the mural paintings is classified into five different categories; You (jacket), Po (overcoat), Go (trousers), Sang (skirt), and Gwan (hat). Comparing these categories with those of other mural paintings lead us to the following conclusions. 1. The length of the You (jacket) reaches below the buttocks and the sleeves are narrow. The edges of the sleeves are decorated with stripes. The You (jacket) over-laps on the right, center, and left sides, and there are many Jikryong (V-collar) and Danryong (rounded collar) styles, but it has a similar tendency to others of the Pyongyang area which exhibit many foreign influences. In a departure from tradition. the belts on the men's You (jackets) have only 3 knots in the front, with the back having more knots than the front. The belts of the women's You (jacket) seem to have had a band or button for fastening. We must re-evaluate the assumption that the You (jacket) and Go (trousers) of the northern peoples had the common characters of a belted You (jacket) and Po (over-coat) and that the Gorum originated from the Goryo or Unified Silla dynasty. The outside of the sleeves are longer and more to the side than the inner garment (underwear) so that the sleeves of the inner garment frequently overlapped the outer dress. The above mentioned facts have lead to the discovery of the "Hansam," "Tosi" and "Geodoolgi." 2. The Po (overcoat) was used only by the upperclasses and differs from those found in other mural tombs. The Po (overcoat) of the noble on the tomb mural is centered with an overlapping Jikryong (V-collar) while the other Po (overcoats) of the upperclasses are characterized by an overlap on the left, a Danryong (rounded collar) with two types of sleeves (wide and narrow). Foreign influences and traditional influences coexist in Po (overcoat). Belts have frontal knots without exceptions. The facts that the belts on the You (jackets) are on the front and the belts on the Po (overcoats) are on the back must be reexamined. 3. Go (trousers) is usually narrow, being wider in the rear and narrower below the knees. They were used by hunters on the back of horses with similar Go (trousers) from the Noinwoowha tombs being typical of the northern peoples. 4. Sang (skirts) are pleated as commonly seen in the Goguryo murals. The size of the pleat is varied, each pleat being characteristically wider and having different colors. Same types of pleat are discovered in Central Asia and China. It is uncertain whether the pleat of Goguryo was originated in Central Asia and China or only interrelated with those of the areas. 5. There are three kinds of Gwan (hats); Nagwan, Chuck, and Heukgun. Nag-wan was worn by the dead lords and their close relations. Chuck has three cone shaped horns. Heukgun was worn by military bandmen and horsemen. There are two kinds of hair styles. The up-style was used by the upperclass people closely related to lords, and other people used the Pungimoung hair style. The hair styles of the men and women are characterized by the Pungimoung style. which is a Chinese influence, but still retain their originality. The costume has a similar tendency from those from Yaksuri mural tombs, Anak No. 2 and Anak No. 3. We need to reexamine the costumes from $4{\sim}5$ century murals according to the Dukheungri murals. The costumes of Goguryo share many common factors with those of Western Asia, Central Asia and Ancient China (Han). It seems due to the cultural exchanges among the Northern peoples, the Western and Central Asians, and the Ancient Chinese. It may have resulted from the structural identity or morphological identity of the peoples, or their common social and natural environments and life styles. It will be very valuable to study the costumes of Japan, China, and Korea to find out the common factors. It is only regretful that the study is not based on direct observations but reported information made by 77 persons, because Dukheungri is an off-limits area to us.