• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.323-326
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• 1999

In this paper, a windmill type ultrasonic motor operated by single-Phase AC electric field was fabricated, and then torque characteristics were investigated. A metal-ceramic composite component was used as the stator\`s vibrator to generate ultrasonic vibrations. The windmill type ultrasonic motors has only three components; a stator element with two wind-mill shape slotted metal endcaps, a rotor and a bearing. In this parer we measured torque, when stator\`s slot was changed Iron 4, 6, 8. Brass metal was pressed with umbrella-type using metal molt then slot of 3 kind was manufactured. The maximum revolution speed was 388(rpm) in the case of a small ultrasonic motor of 11.35 mm diameter, 8 slot and 1.01 mm thickness. The maximum torque of 0.17 mNm was obtained at a speed of 131 rpm.

• 한국응용곤충학회지
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• 제5_6권
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• pp.59-63
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• 1968

본 논문은 1963-1965년 사이에 구기자 혹응애의 생태에 관하여 조사 관찰한 결과의 일부를 보고한 것이다. (1) 구기자 혹응애의 기주식물은 순기자나무 까마중 및 고추 등이다. (2) 이동과 전파는 물리적인 매개체에 의하며, 풍향은 이동과 전파에 영향이 크다. (3) 1자당 산난수는 평균 $28.5\pm0.499$개이고, 란기간은 평균 $7.0\pm0.447$일이다. 유충기문은 평균 $4.33±\pm0.667$일이다. (4) 식입 후 경과일별 충영의 크기는 1일째는 평균 $290.5\pm0.3415\pm$ 이며, 25일째는 평균 $3260.5\pm0.5157\mu$이다. (5) 성충기간은 25-30일이고 식입 후 산난일은 6일 이다. (6) 연발생회수는 6-7회이며, 성충태로 충영내에서 월동하여 5월 하순에 제1회 성충이 나타난다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.236.1-236.1
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• 2010

Due to global warming, the need to secure an alternative resource has become more important nationally. Due to the high tidal range of up to 9.7m on the west coast of Korea, numerous tidal current projects are being planned and constructed. The rotor, which initially converts the energy, is a very important component because it affects the efficiency of the entire system, and its performance is determined by various design variables. In this paper, a design guideline of current generating HAT rotor and acceptable field rotor in offshore environment is proposed. To design HAT rotor model, wind mill rotor design principles and turbine theories were applied based on a field HAT rotor experimental data. To verify the compatibility of the rotor design method and to analyze the properties of design factors, 3D CFD model was designed and analysed by ANSYS CFX. The analysis results and findings are summarized in the paper.

• 한국생산제조학회지
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• 제21권2호
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• pp.305-310
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• 2012

Planetary gear box is a power transmitter having very high gear ratio in compact volume. The planetary step-down gear box converts high speed and low torque into low speed and high torque, which is widely used in constructional and industrial machinery field. And, the planetary step-up gear box does vice versa working, which is used as main gear box of large sized wind mill system. The large sized planetary gear box must be performed the normal-opposite rotation test as a its durability test for achieving the reliability. The large sized planetary gear box is composed by triple gear trains of sun gear, carrier, and ring gear. If input power is supplied into one of them and the other is fixed, and then another becomes the output part. In this paper, we designed a new test equipment which can do rapid normal and opposite rotational change with only small displacement by supplying test power using the above rotation (driving) characteristics and hydraulic cylinder and link, and also compared and analyzed with existing method through various experiments.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.122-131
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• 2001

Pakistan being the 6$^{th}$ largest sugar producer has over 75 sugar mills with annual production capacity of about 2.4 million tons during 1996-97. The contribution of Sindh with 27 sugar mills is recorded over 50% of the total sugar production. The majority of the mills in Pakistan use the Defecation-Remelt-Phosphitation (DRP; 24 mills), Defecation-Remelt-Carbonation (DRC; 21 mills) and Defecation-Remelt Carbonation and Sulphitation (DRCS; 11 mills) process. Seven of the 75 sugar mills in Pakistan also produce industrial alcohol from molasses, a by- product of sugar manufacturing process. These sugar industries also produce fly ash, which have been found to contain unburned carbon and reach as far as four-kilo meter area with the wind direction, threatening the community health of people living around, besides posing other aesthetic problems. The untreated wastewater, in many cases, finds its way to open surface drains causing serious threat to livestock, flora and fauna. One study showed that fly ash emitted from the chimneys contain particle size ranging from 38 ${\mu}{\textrm}{m}$ to 1000 ${\mu}{\textrm}{m}$. About 50 per cent of each fly ash samples were above 300 ${\mu}{\textrm}{m}$ in size and were mostly unburned Carbon particles, which produced 85% weight loss on burning in air atmosphere at 1000${\mu}{\textrm}{m}$. This fly ash (mostly carbon) was the main cause of many health and aesthetic problems in the sugar mill vicinity. The environmental challenge for the local sugar mills is associated with liquid waste gaseous emission and solid waste. This paper discusses various waste recycling technologies and practices in sugar industries of Pakistan. The application of EM technology and Biogas technology has proved very successful in reusing the sugar industry wastewater and mud, which otherwise were going waste.

• 한국농촌생활과학회지
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• 제9권1호
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• pp.1-7
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• 1998

The purpose of this study is to investigate the effect of wearing sweat suit on sweating rate during jogging. 4 healthy female students served as subjects in the experimental chamber which was controlled 22$\pm$1$^{\circ}C$, 60$\pm$10%RH and no wind. The experimental clothes were Sweat Suit (SS) and General Suit (GE), SS was the product of R sports wear company which was consisted of long-sleeved jumper (100% polyester) and full length trousers (100% polyester) and GE were consisted of long sleeved shirt (100% cotton) and full length trousers (100% cotton). The subject wore same socks and shoes in both experimental clothes SS and GE. The subject reported at the experimental chamber at the same time on each experimental day. exchanged their clothes to the experimental clothes SS or GE, wore all sensors for the physiological measurements and had a rest in a sitting posture about 40 minutes. After rest, the subject carried out 30 min jogging on the tread mill with the speed 3.6miles/hour and during the jogging rectal temperature, skin temperatures (7 sites of the skin surface), heart rate, VO2, and evaporative weight loss were measured continuously and compared between two experimental clothes SS and GE. The major findings were as follows : The increase in rectal temperature during 30 min jogging was higher in experimental clothes SS than in GE and mean slim temperature kept higher in SS than in GE. VO2 and heart rate were a little bit higher in the later period of jogging in SS than in GE. The evaporative weight loss was greater in SS than in GE. These results indicate that the thermophysiological responses and sweating rate differs according to the wearing suit even though the subject performed same exercise.

• 한국농촌건축학회논문집
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• 제10권1호
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• pp.101-109
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• 2008

It is very hard to find out Tongbanga-millhouse installed nearby a streamlet to use water with Tongbanga(a kind of water-mill) to polish cereals by pounding like a visage of its old days. It plays an important part in folkloric, architectural and educational aspects. The purpose of this study is to analyse the architectural features of Tongbanga and millhouse itself so that to find the way how to build and fabricate the materials and frame members. Therefore this study has been focused on the composition principle and fabrication method of Tongbanga-millhouse on the side of architecture. The fabrication methods of its house in accordance with regular sequences are as follows. ${\cdot}$ Firstly the decision of location of Tongbanga-millhouse and Hwak(a big mortar made of stone). ${\cdot}$ Slantly three rafter installation at an angle of $50^{\circ}$ to err on the safe side and then slantly fifteen rafter installation making a circular cone shape. ${\cdot}$ Installation of twigs to be circles from bottom to top. ${\cdot}$ Manifoldly covering of trunks peeling the barks from flax plants. ${\cdot}$ Threefoldly thatching with upside barks of oak trees. ${\cdot}$ Placing woods alike rafter on the bark thatches as a weight not to fly away by wind. ${\cdot}$ Binding woods alike rafter with vines of arrowroots to maintain the proper place. The decayed Tongbanga-millhouse by means of upper ways was restored out of all recognition.

• 한국입자에어로졸학회지
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• 제17권3호
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• pp.55-69
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• 2021

Chungnam region accounts for the largest SO_X (22.8%) emission with the second-largest NO_X (10.8%) emission in Korea due to the integration of many large industrial sources including a steel mill, coal-fired power plants, and petrochemical complex. Air pollutants emitted by large industrial sources can cause harmful problems to humans and the environment. Thus, it is necessary to understand dispersion patterns of air pollutants from large industrial sources in Chungnam to characterize atmospheric contamination in Chungnam and the surrounding area. In this study, seasonal atmospheric dispersion characteristics for SO_X, NO_X, and PM2.5 from ten major point sources in Chungnam were evaluated using HYSPLIT 4 model, and their contributions to SO₂, NO₂ concentrations in the regions near the source areas were estimated. The predictions of the HYSPLIT 4 model show a seasonal different dispersion pattern, in which air pollutants were dispersed toward the southeast in winter while, northeast in summer. In summer, due to weaker wind speed, air pollutants concentrations were higher than in winter, and they were dispersed to the metropolitan area. The local emissions of air pollutants in Taean area had a greater influence on the ambient SO₂ and NO₂ concentrations at Taean, whereas SO_X and NO_X emissions from large sources located at Seosan showed relatevely little effect on the ambient ambient SO₂ and NO₂ concentrations at Seosan.

• 한국산림과학회지
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• 제94권6호
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• pp.402-409
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• 2005

제주도에 조성한 리기다소나무(Pinus rigida Mill.), 리기테다소나무(Pinus rigida ${\times}$ P. taeda) 채종원내 조성년도가 다른 6개 식재지에서 푸사리움가지마름병(pitch canker) 피해를 입은 지 7년째 되는 잔존 임목의 피해를 개체별로 판정하여 채종원 및 수종간 피해도 차이를 비교하였으며 이들 중 표현형에 의해 선발한 내병성, 이병성 선발목의 반형매 차대 2년생 묘목을 리기다소나무와 해송(P. thunbergii Parl.)에서 분리한 푸사리움가지마름병균(Fusarium circinatum)으로 인공접종 한 뒤 기주의 감염성 여부를 검정하였고 균주들의 병원성 여부를 확인하였다. 조사한 특성 중 두 채종원(상효, 한남)내 리기테다소나무 4 식재지간에 SC(줄기궤양)에서 통계적 유의성(${\chi}^2=7.76$; P=0.05)이 있는 것으로 나타났다. 상효채종원내에서 리기다소나무가 리기테다소나무에 비해 수관피해도(top kill)와 가지끝 마름증상(branch tip symptoms)에서 피해도가 높은 것으로 나타났다. 인공접종 결과 내병성 후보목 차대가 이병성 후보목 차대에 비해 14% 높은 고사율을 보였는데, 이는 화분수의 영향이나 표현형에 의한 후보목 선발에서 온 결과로 사료된다. 처리균주 5개 중 C-6-L(9)과 C-6-L(19) 균주가 각각 68%, 60%의 고사율을 보여 차후 추진할 대규모 인공접종용 균주로 사용할 수 있을 것이다. 인공접종 실험을 통해 1차 선발된 내병성 후보목 개체들은 푸사리움가지마름병 저항성 품종 육종을 위한 유전적, 생화학적 기초 연구에 유용한 재료로 이용 될 수 있을 것으로 본다.