• 제목/요약/키워드: loom

검색결과 198건 처리시간 0.029초

벼 상온통풍건조의 최소풍량비에 관한 연구 (Minimum Specific Airflow Rate Requirements for Natural Air Drying of Rough Rice in Korea)

  • 금동혁;박선태
    • Journal of Biosystems Engineering
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    • 제21권1호
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    • pp.60-71
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    • 1996
  • The purposes of this study were to develop a simulation model and to determine minimum specific airflow rate requirements for natural air drying of rough rice in Korea. A simulation model was developed considering energy and mass balances within grain bed, drying and rewetting rates, and hysterisis effect between sorption and desorption isotherms. As the results of validation test, the moisture contents predicted by the model agreed very well with the actual data. The criteria for determining minimum specific airflow rate requirements was that the top loom layer in the bin be dried to a moisture content below 16 percent wet basis with less than 0.5% drymatter decomposition. The minimum specific airflow rate requirements in 13 locations of Korea were presented based on the worst one among the past 7 to 13-year weather data. These requirements were also presented for all the combinations of three harvest dates and four harvest moisture contents. Specific airflow rate requirements seemed to be half by each 2 percent reduction in moisture content from 24 percent. As harvest date was delayed by 10 days from October 1, these requirements were reduced by about 20 to 40 percent.

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초전도 전력케이블의 1선 지락고장 특성 해석에 관한 연구 (A Study on the Single Line-to-Ground Fault Analysis of HTS Power Cable)

  • 제향호;방종현;김재호;심기덕;조전욱;장현만;이수길;박민원;유인근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.593-594
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    • 2006
  • High temperature superconducting(HTS) power cable is expected to be used for power transmission lines supplying electric power for densely populated cities in the near future. Commercializing of HTS power cable is coming. Simulation is required for safety before install of HTS power cable, a fabrication model used at the power system simulation. In this paper, we shows a single line-to ground fault analysis in the grid system which has a loom length HTS power cable. The authors developed a single line-to ground fault current calculation method which is considering the shield layer of HTS power cable. In the calculation, the T type equivalent circuit is used to derive the mutual inductance of the HTS power cable

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초전도 전력케이블의 1선 지락고장 특성 해석에 관한 연구 (A Study on the Single Line-to-Ground Fault Analysis of HTS Power Cable)

  • 제향호;방종현;김재호;심기덕;조전욱;장현만;이수길;박민원;유인근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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    • pp.2225-2226
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    • 2006
  • High temperature superconducting(HTS) power cable is expected to be used for power transmission lines supplying electric power for densely populated cities in the near future. Commercializing of HTS power cable is coming. Simulation is required for safety before install of HTS power cable, a fabrication model used at the power system simulation. In this paper, we shows a single line-to ground fault analysis in the grid system which has a loom length HTS power cable. The authors developed a single line-to-ground fault current calculation method which is considering the shield layer of HTS power cable. In the calculation, the T type equivalent circuit is used to derive the mutual inductance of the HTS power cable.

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동축이중원관 분류에 있어서의 유동 특성에 관한 연구 (A Study on the Flow Characteristics in Double Coaxial Pipe Jets)

  • 신창환;김경훈
    • 한국분무공학회지
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    • 제1권4호
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    • pp.46-53
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    • 1996
  • The present study is aiming at improving the performance of main nozzle of an air jet loom with a modified reed and auxiliary nozzles. The double coaxial pipe jets consisting of a central air jet and an annular air jet have been experimentally investigated. The duter jet has a potential core and a constant velocity. The inner jet through an inner long pipe is induced by the subatmospheric pressure near the inner nozzle edge, and the jet velocity of an inner pipe is always lower than that of a outer pipe. The static pressures of the main nozzle over a wide range of the nozzle tank pressure were measured, and the nozzle velocity and Mach numbers were analytically calculated. Experiment81 results indicate that the critical condition of Mach number of unity to occur at the two positions in a main nozzle; one of them is the needle tip and the other is the acceleration tube exit An increase in the tank pressure causes the critical throat condition to occur at the two positions above. The velocity of acceleration-tube exit is maximum at the critical length L* and flow patter in acceleration-tube over critical lengh remains unstable.

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염수침입 현상의 전기비저항 분석에 대한 지구통계기법의 응용

  • 심병완;정상용;김병우
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 추계학술발표회
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    • pp.92-96
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    • 2001
  • Although the problem of seawater intrusion at the coastal aquifer was recognized before over one hundred years at the coastal aquifer, much groundwater keep on being salinitized by several reasons such as groundwater exhaustion, coastalline change, and human activities. The horizontal and vertical electrical soundings and geostatistical methods were used to define the local characteristics of saltwater intrusion and to estimate the saltwater interface in the southeastern area of the Pusan City. The 24 points of the Schlumberger vertical electrical soundings(VES) to loom depth and the 2 lines of dipole-dipole horizontal soundings are peformed. The resistivity data have lognormal distributions. The horizontal extents of saline water intrusion were estimated from the inversion of horizontal prospecting data. Lognormal ordinary kriging is used in A-A' resistivity profiles on May and July because the data have stationary models in semivariograms. Lognormal IRF-k kriging is used for the isopleth maps using vertical resistivity data. The 10 ohm-m resistivity line on the isopleth maps of 21m, 30m, 50m, and 70m depth using resisitivity data measured in July is sifted to the east, cpomparing that of the isopleth maps measured in May. The kriged vertical and horizontal resistivity isopleth maps suggested that the geostatistical methods can be used to define the variation of earth resistivity distribution at the saltwater interface.

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직물의 조직에 따른 밀도, 두께가 보온성에 미치는 영향 (The Effect of Density and Thickness to the Warmth by different Weaves of Fabric)

  • 한명숙
    • 대한가정학회지
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    • 제12권1호
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    • pp.459-471
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    • 1974
  • This study was carried out on the thermal transmission on account of variation of weaves and researched on the selection of the most suitable weaves for warmth. Also the interrelation among the density, thickness and thermal transmission by different weaves was studied, the author has woven three fundamental weaves, five weaves derived from the fundamental weaves and two special weaves for the purpose of experiment. In weaving of fabrics for experiments the lever type hand loom was used. Testing of texture was carried out according to KS and ASTM. The thermal transmission was also tested by as cooling method which were developed by the author. The conclusions of experiments were as follows. 1. Matt weaves, honey comb weaves and satin weaves having long floating yarns have large cover factor and were thicker. these structures of the weaves were good in warmth. 2. Thermal transmission was reciprocated to the cover factor, thickness and value of cover factor multiplied by thickness : It was found that the weaves of woven fabrics for warmth had better use of satin weaves, Matt weaves, Granite weaves and Honey comb weaves. In the time of warmth is not the first purpose, had better use of Rib weaves. Plain weaves and Twill weaves with thin thickness and high thermal transmission.

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연약지반상 고속철도 노반 축조시 지오셀 시스템의 효과 (Reinforcing Effect of Geocell on Soft Soil Subgrade for High-speed Railroad)

  • 조삼덕;윤수호;김진만;정문경;김영윤
    • 한국지반공학회논문집
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    • 제18권2호
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    • pp.5-12
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    • 2002
  • 본 연구에서는 연약지반 상에 축조되는 고속철도 노반을 보강하기 위해 사용된 지오셀의 효과를 평가하기 위해 다양한 현장 평판재하시험과 동적 모형토조시험을 수행하였다. 실험결과로부터 지오셀 사용에 의한 보강노반의 두께 감소효과와 노상 지지력 증가효과가 평가되었다. 지오셀 1층과 복토 loom를 사용하면 동일한 두에의 쇄석층을 사용할 경우와 비교하여 3~4배의 지지력 개선효과가 있으며, 노반두께를 약 35cm 정도 감소시킬 수 있는 것으로 평가되었다.

아스파라가스 줄기마름병(경고병)의 방제에 관한 연구 (Studies on the control of stem blight of asparagus caused by Phoma asparagi Sacc)

  • 최진규;권영삼;유황현
    • 한국응용곤충학회지
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    • 제20권2호
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    • pp.83-86
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    • 1981
  • 아스파라가스 줄기 마름병 (경고병)의 효과적인 방제 대책을 수립하고자 시험한 결과 1. 줄기 마름명은 5월하순부터 발생하여 7월이후 강우와 함께 급격히 증가하였고, 2. 약제살포를 겸하여 모경대치하고 plastic film으로 피복하였을 해가 약제살포만 할때보다 줄기 마름병의 발생이 현저히 줄어들었다. 3. Plastic film으로 피복하였을 때의 $7\~8$월중 토양 수분변화는 아스파라가스의 생육에 적당한 pF 2.9에 비교적 가까은 상태를 유지할 수 있었다. 4. 모경대치를 할 겅우 대조구보다 수량이 떨어졌으나 plastic film을 피복할 경우는 대조구보다 약 $30\%$ 정도 증수되었다.

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중국내 묘족의 직물에 나타난 기법과 문양 고찰 (The Study on Technique and Design Appeared in Textile of Miaos in China)

  • 부애진;홍정민
    • 복식
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    • 제37권
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    • pp.149-162
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    • 1998
  • This study is thed Embroidery, Cross-stitchery, Weaving, Wax-Printing of technique and design appeared in textile of Miaos dwells in south-west among the minority people of china. The study is as follows. First, the technique of textile1) satin stitch, couching stitch, french-knot stitch, etc. using anther silk thread or cotton thread color 2) cross-stitchery 3) hand-weaving technique which is shaped other warp or weft using simple loom 4) the technique of dyeing of pattern using effect with wax. These methods are singly used mixing together, therefore doubled beauty. Second, these technuque of ornament have other independence, specially ornament apron, sling, sleeve borders, slack borderss, edge of upper garment, take off and put on easily, heighten effect of various ornament, can preserve many years. Third, Maker, female born in this country fashion by need of herself, used liberal method shown in unique creativity of life. This texture make standards capable female proud of intelligent and skill of herself. Fourth, Design appeared in textile like as pattern flying bird in the sky, strolling beast in the field, lion rolling gem, laughing dragon winding snake at gem, birks, flowers, fish, butterfly is used as the wish of long life, a lucky sign. They expressed creativity and unique conception using formation : the technique transform other shape using by omitting or adding or overestimating. Geometric pattern of tartan, revealing, Fifth, composition structure having balance and symmetry or contradiction towards center and circumstance of the center harmonized repeatedly method, expressed unique artful attraction by full composition.

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수동형 SONAR 시스템을 사용한 지하 진원지의 추정 (Position estimation of underground acoustic source origin using a passive SONAR system)

  • 장순석;이제형;안흥구;최현호
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1999년도 학술발표대회 논문집 제18권 1호
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    • pp.103-108
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    • 1999
  • The aim of the work described in this paper is to develop a complex underground acoustic system which detects and localizes the origin of an underground hammering sound using an array of hydrophones located about loom underground. Three different methods for the sound localization will be presented, a time-delay method, a power-attenuation method and a hybrid method. In the time-delay method, the cross correlation of the signals received from the array of sensors is used to calculate the time delays between those signals. In the power-attenuation method, the powers of the received signals provide a measure of the distances of the source from the sensors. In the hybrid method, both informations of time-delays and power-ratios are coupled together to produce better performance of position estimation. A new acoustic imaging technique has been developed for improving the hybrid method. This new acoustic imaging method shows the multi-dimensional distribution of the normalized cost function, so as to indicate the trend of the minimizing direction toward the source location. For each method the sound localization is carried out in three dimensions underground. The distance between the true and estimated origins of the source is 28m for a search area of radius 250m.

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