• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.215-224
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• 2009

A survey on the actual state of heating, cooling, ventilation, and air-flow and experimental measurement of temperature and humidity distribution in tomato greenhouse were performed to provide fundamental data required in the development of air-flow control technology. In single-span plastic houses, which account for most of 136 tomato greenhouses surveyed, roof windows, ventilation and air-flow fans were installed in a low rate, and installation specs of those facilities showed a very large deviation. There were no farms installed greenhouse cooling facilities. In the hot air heating system, which account for most of heating type, installation specs of hot air duct showed also a large deviation. The exhaust air temperature and wind speed in hot air duct also were measured to have a big difference depending on the distance from the heater. We are using the maximum difference as indicator to determine whether temperature distribution is uniform. However if the temperature slope is not identical in greenhouse, it can't represent the uniformity. We analyzed relation between the maximum difference and the uniformity of temperature and humidity distribution. The uniformity was calculated using the mean and standard deviation of data from 12 measuring points. They showed high correlation but were represented differently by linear in the daytime and quadratic in the nighttime. It could see that the uniformity of temperature and humidity distribution was much different according to greenhouse type and heating method. The installation guidelines for ventilation and air-flow fan, the spread of greenhouse cooling technology for year-round stable production, and improvement of air duct and heating system, etc. are needed.

• Horticultural Science & Technology
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• v.17 no.6
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• pp.737-741
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• 1999

We surveyed the physiological disorders of fruit vegetables grown in the greenhouse in Kyungbuk province in 1998. Greenhouses used for cultivation were mostly single or multi-span iron pipe houses covered with polyethylene film. Single span greenhouses were used for strawberry, oriental melon and watermelon. Fifty six percent of the surveyed farms was a mono-cropping system for oriental melon and tomato. There were greenhouses used for successive cultivation for 10 years or more for strawberry and oriental melon in Koryeong and Seongju. Varieties of fruit vegetables cultivated were diverse, especially in cucumber and watermelon. In strawberry, malformed fruits were observed most frequently in March and the small fruits at late harvest period. Leaf chlorosis, stunt plants and runner outbreak were also found during the growing season. In tomato, occurrence of malformed fruits was severe from March to May, and occurrence of cracked fruits and blossom- end rot was also severe in October and November. The self topping and abnormal stem in tomato were problem in hydroponic cultures in August and November, respectively. Malformed cucumber fruits, such as curved, club shaped, irregular shaped and narrow necked, occurred at late season. Umbrella-shaped leaf in cucumber in summer were caused by calcium deficiency. Most serious disorders were fermented and malformed fruits occurring from March to May in oriental melon, and cracked fruits occurring from April to May in watermelon. At late growing stage of melons the leaf chlorosis occurred with complex symptoms of leaf disease. Growers had little knowledge on physiological disorders, and also on diagnose and measures to cure the disorders. Most growers pointed out that poor soil environment and temperature management in the greenhouse as the main causes of physiological disorders.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.04a
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• pp.87-91
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• 1999

봄철 하우스 수박 무가온 조숙재배에 알맞는 보온방법을 개발하고자 아취형 단동하우스에 PE필름터널, 유공필름＋축열물주머니, 유공필름터널＋부직포터널구를 처리하고, 삼복꿀수박을 '98년 3월 23일 정식하여 4월 27일까지 36일간 터널피복재의 보온성을 검토한 결과는 다음과 같다. (1) 보온재 피복 재배 기간중 터널내 최저온도는 PE터널구 10.9$^{\circ}C$에 비하여 유공필름터널에 축열물주머니구와 부직포터널구는 각각 0.9, 2.1$^{\circ}C$ 높았다. (2) 3월하순 활착기의 하우스내 일사량은 실외 175.2w/$m^2$ 비하여 124.2w/$m^2$로 51w/$m^2$ 낮았다. (3) 터널피복재 환기작업에 따른 소요 노동력은 PE터널구 25.2시간/10a/36일에 비하여 유공필름터널＋부직포터널구는 32.4시간으로 7.2시간/10a/36일 증가하였으나, 유공필름터널＋축열물주머니는 개폐작업으로 인한 투하 노동력이 없었다. (4) 터널재배 기간중 유공필름터널＋부직포터널구가 초기생육이 촉진되었으며, 생육후기에 발생한 흰가루병 이병엽율은 2.8%로 현저히 감소하였다. (5) 수박의 수확기는 PE필름터널구 6월 22일에 비하여 유공필름터널＋축열물주머니와 부직포터널구는 6월 12, 15일로 7, 10일 앞당겼으며, 수량은 PE터널구 2,385kg/10a에 비하여 20, 32% 각각 증수하였다.

• 제어로봇시스템학회:학술대회논문집
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• 1986.10a
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• pp.503-505
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• 1986

주어진 제어대상 모델에 대하여 제어기를 구성하여 실제로 적용하는 경우 모델의 불일치, 모델링에서 고려하지 않은 외란(disturbance), 측정잡음등에 의하여 성능이 설계시와 달라진다. 실제적용에서도 성능을 계속 유지하기 위하여 제어기는 안정성, 계수변화(parameter variation)에 대한 강인성(robustness), 외란상쇄(disturbance rejection) 및 측정잡음에 둔감함등의 특성을 가져야 한다. 귀환(feedback)을 사용하여 제어기를 구성하는 경우 위의 모든 조건을 만족 시킬 수 없으므로 제어목적에 따라 적당한 조건을 선정하여 중요한 특성을 주로 갖게 한다. 본 논문에서는 쌍동선(small waterplane area twin hull ship-SWATHS)에 대하여 PID, LQ, LQG 제어기를 구성하여 안정성, 계수 변화에 대한 강인성, 외란 상쇄 및 측정잡음의 영향을 비교하였다. 쌍동선의 경우 다른 단동선(mono hull ship)에 비하여 접수면(waterplane)이 적으므로 무게증변을 흡수할 수 있는 복원력이 약하여 적은 외력에도 상하동요(heave)와 종동요(pitch)가 심하게 일어난다. 이러한 동요를 줄이는 것이 쌍동선의 제어목적이다. 본 연구에서는 먼저 선형화된 수직축 운동방정식을 이용하여 선체운동의 모델을 구했으며 중첩의 원리(super-position theorem)에 의하여 주파수 응답의 합으로 파도입력을 모델링 하였으며 제어를 위하여 필요한 측정치는 IMU(Inertial Measurement Unit)에서 제공된다고 가정하였다. 쌍동선의 동요의 원인은 파도, 바람, 조류 등이 있으나 파도에 의한 영향이 가장 크므로 본 논문에서는 파도에 의한 영향만을 고려하였다. 파도는 쌍동선에 외란으로 작용하며 측정할 수 없는 양이므로 PID, LQ 제어에서는 제어모델에 포함되지 않지만 LQG 제어에서는 제어모델에 포함된다. LQG 제어의 경우 제어모델에 파도를 백색잡음으로 가정하고 제어기를 구성한 것 (LQG1)과 2차의 쉐이핑필터(shaping filter)를 사용하여 구성한 것(LQG2)으로 나누었다.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.10a
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• pp.90-95
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• 2000

This paper presents the vergence control of a parallel stereo camera and its application to underwater stereo camera to enhance the working efficiency of underwater vehicles that equips with manipulators in seabed operation. The stereo camera consists of two parallel lenses mounted on a lateral moving base and two CCD cameras mounted on a longitudinal moving base, which is embedded in a small pressure canister for underwater application. Because the lateral shift is related to the backward shift with a nonlinear relation, only one control input is needed to control the vergence and focus of the camera with a special driving device. We can get a clear stereo vision with the camera for all the range of objects in air and in water, especially in short range objects. The control system of the camera is so simple that we are able to realize a small stereo camera system and to apply it to a stereo vision system for underwater vehicles. This paper also shows how to acquire the distance information of an underwater object with this stereo camera. Whenever we focus on an underwater object with the camera, we can obtain the three-dimensional images and the distance information in real-time.

• Journal of Korean Medical classics
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• v.19 no.2 s.33
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• pp.11-29
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• 2006

${\ulcorner}$동의수세보원(東醫壽世保元)${\lrcorner}$소음인편(少陰人篇), 유신수열표열병화위수한리한병양대부분조성(由賢受熱表熱病和胃受寒畵寒病兩大部分組成). 신수열표열병(賢受熱表熱病), 분위울광증(分爲鬱狂證), 망양증(亡陽證), 태양병궐음증등삼개병증(太陽病厥陰證等三個病證). 상한론적하초축혈증시사기재하조적혈증(傷寒論的下焦血證是邪氣在下蕉魚的血證), 용저당탕(用抵當湯), 도인승기탕등파열해열지제치료(桃仁承氣湯等破血解熱之劑治療). 단동무인위상한하초축혈증위울축방광증(但東武認爲傷寒下蕉蓄血證爲鬱蓄醫謗胱證) 기병기시신국양기피사소거(其病機是賢局陽氣被邪所拒), 불능상소어비국(不能上疏於脾局), 울축방광(鬱蓄膀胱). 고동무장양기울축적병증시(故東武將陽氣鬱蓄的縮的病證視), 위울광증(爲鬱狂證), 장양기누설적한출시위망양증(將陽氣漏泄的汗出視寫亡陽證). 동무장태양상풍무한증(東武將太陽傷風無汗證), 하조축혈증(下蕉蓄血證), 귀속우울광초증(歸屬于鬱狂初證), 장열입혈실증(將熱入血室證), 양명병위가가실증(陽明病胃家實證), 귀속우울광중증(歸屬于鬱狂中證), 장양명병조열광언증(將陽明病湖熱狂言證), 귀속우울광말증(歸屬手驚狂末證), 장태양상풍한출증(將太陽傷風出證), 귀속우망양초증(歸屬于亡陽初證), 장양명병(將陽明病), 불오한(不惡寒) 반오열(反惡熱) 한자출증(汗自出證), 귀속우망양중증(歸屬手亡陽中證), 장양명병(將陽明病), 발열한다증(發熱汗多證), 귀속우망양말증(歸屬手亡陽末證). 타인위소음인음병당유복만자리(他認爲少陰人陰病當有腹題滿自利), 시병등증상(時病等症狀). 초기약무복통자리적증상이견궐음증(初起若無複痛自利的症狀而見厥歐陰證), 인위시정사상지일구이경기쇠갈소치(認爲是正邪相持日久而正氣衰竭所致).

• Journal of Biosystems Engineering
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• v.18 no.1
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• pp.60-70
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• 1993

In this study, the environment variations and distributions in different types of greenhouses were measured and analyzed. The elements of environment analyzed were temperature, relative humidity, illumination, carbon dioxide and wind velocity. The analyzed greenhouse types were auto-multi type which has an automatic environment control system and multiple continuous arches, regular-multi type which has an temperature control system and multiple continuous arches, and single arch type which has no environment control system without manual temperature keeping method. The results of this study can be used for the greenhouse building and managements.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.61-62
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• 2011

비닐하우스는 매우 세장한 강관부재들을 교차 결합하여 조립한 철골 구조물의 한 종류이다. 현행 설계기준으로 단동 비닐하우스의 최대 구조성능은 풍하중 40m/s, 설하중 50cm에 달한다. 그러나 설계 단계에서는 부재들의 교차결합 특성 및 부재가 직접 지반에 삽입되는 기초의 특성이 적합하게 반영되지 않는 문제점이 있다. 따라서 가력시험을 통하여 반강접 특성을 갖는 부재 교차부 및 지반삽입기초 조건이 구조물의 거동에 미치는 영향을 분석하였다. 부재 교차부가 강접 조건일 경우와 비교하여 교차부가 반강접일 경우에는 재하지점의 수평강성이 최대 54% 작게 나타났으나 주변 교차절점들에서의 에너지 흡수로 인하여 재하지점과 수평으로 3m 떨어진 지점에서는 반대로 최대 39% 큰 값을 보였다. 지반삽입기초의 경우에는 고정조건과 비교하여 재하지점의 수평강성이 최대 32% 작게 나타났으며, 지점부에서는 기초 조건의 영향으로 최대 26%의 휨강성 증가 효과를 보였다. 부재 교차부와 기초 조건이 구조물의 정적거동에 미치는 영향을 확인하였으나 최대내력과 강성 산정을 통한 구조성능 평가 방법의 개발이 필요할 것으로 판단된다.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.4
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• pp.75-86
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• 1992

This paper reports theoretical and experimental investigation into the added resistance of SWATH ships in waves. It was revealed from the experimental investigations on various SWATH models that the resistance of the SWATH models in waves is considerably reduced over part of the speed range as the wave height increases. As a first step to Identify it, the first and second order wave forces have been investigated barred on a linearised 3-D diffraction theory together with simplified boundary conditions and same results are reported herein. Also, the speed performance of SWATH ships in rough seas is compared with those of equivalent monohulls as well as with those of advanced high speed marine vehicles.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.1140-1141
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• 2017

Depth of SWASH(Small Waterplane Area Single Hull) vessel which is an input value of its control system is measured by ultrasonic sensor. Distance to the its center of gravity can be simply calculated through ultrasonic sensor attached to the front of the vessel from the known values. However, it is to be calibrated with respect to its position for the accurate depth because it has geometric relation between the measurement value of ultrasonic sensor and the depth. In this research, depth calibration method of SWASH vessel using its position and ultrasonic sensor is introduced.