• 제목/요약/키워드: HEIGHT

검색결과 20,459건 처리시간 0.047초

저탄장 시설에 설치된 방풍벽 높이에 따른 비산탄진 확산특성에 관한 수치해석 (Numerical Investigation on Influence of Windbreak Wall Height on Dust Scattering Characteristics)

  • 정찬호;이진운;신동환;김명민;이성혁
    • 한국분무공학회지
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    • 제19권3호
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    • pp.136-141
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    • 2014
  • This study reports numerically the characteristics of dust scattering around the coal storage pile yards, substantially affected by the windbreak wall height. The dust scattering is closely associated with the frictional effect of wind flows as well as the pressure variation that consequently affect the dust particle behavior. In the present study, with the use of the commercial code of FLUENT, the distribution of wind velocity and pressure are predicted around coal storage pile yard for four different heights of the wind break wall. From the results, it was found that for the case 1 with the outer windbreak wall height of 3 m and inner windbreak wall height of 6 m, the amount of scattering dust for a year was estimated to be 1451 kg, whereas for the case 4 where a height of outer windbreak wall is 10 m and a height of inner windbreak wall is 16 m, the amount of scattering dust for a year was 358 kg. It shows that the dust scattering can be reduced by 75%, indicating important role of windbreak wall height on particle scattering. The numerical results would be useful in decision of the appropriate height of windbreak wall for decreasing the amount of scattering dust under various environmental conditions.

성장에 대한 유전적.환경적 요인의 영향 (Effect of Genetic and Environmental Factors on Growth)

  • 최민형;김덕곤;이진용
    • 대한한방소아과학회지
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    • 제24권3호
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    • pp.138-149
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    • 2010
  • Objectives: The purpose of this study is to estimate genetic and environmental factors which can effect growth, and predict final height using this factors. Methods: Correlation analysis and regression analysis were conducted between measurements of height and Genetic & environmental factors through survey from 1352 child & adolescent patients. Results: Factors which have correlation with height percentile are MPH(Mid-Parental Height), NBW(Neonatal body weight), anorexia, dyspepsia, atopic dermatitis, frequency of breakfast and quality of sleeping time. MPH has moderate relation, NBW and anorexia have fair relation, and other factors have linear but poor relation. Regression equation from factors which have correlation and height percentile has 26.9% of predictive power. Regression equation considering only genetic factor has 20.4%. MPH has the most effect on height percentile. Anorexia has more effect than NBW. Other factors also have small and similar effect. Conclusions: Height of parents has the most effect on growth, anorexia, dyspepsia, atopic dermatitis, frequency of breakfast and quality of sleeping time also has effect.

Current Status of Tree Height Estimation from Airborne LiDAR Data

  • Hwang, Se-Ran;Lee, Im-Pyeong
    • 대한원격탐사학회지
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    • 제27권3호
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    • pp.389-401
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    • 2011
  • Most nations around the world have expressed significant concern in the climate change due to a rapid increase in green-house gases and thus reach an international agreement to control total amount of these gases for the mitigation of global warming. As the most important absorber of carbon dioxide, one of major green-house gases, forest resources should be more tightly managed with a means to measure their total amount, forest biomass, efficiently and accurately. Forest biomass has close relations with forest areas and tree height. Airborne LiDAR data helps extract biophysical properties on forest resources such as tree height more efficiently by providing detailed spatial information about the wide-range ground surface. Many researchers have thus developed various methods to estimate tree height using LiDAR data, which retain different performance and characteristics depending on forest environment and data characteristics. In this study, we attempted to investigate such various techniques to estimate tree height, elaborate their advantages and limitations, and suggest future research directions. We first examined the characteristics of LiDAR data applied to forest studies and then analyzed methods on filtering, a precedent procedure for tree height estimation. Regarding the methods for tree height estimation, we classified them into two categories: individual tree-based and regression-based method and described the representative methods under each category with a summary of their analysis results. Finally, we reviewed techniques regarding data fusion between LiDAR and other remote sensing data for future work.

Orchargrass - Red Clover 초지의 예취빈도와 높이가 목초의 수량과 품질에 미치는 영향 (Effect of Cutting Frequency and Height on the Herbage Yield and Quality of Orchargrass - Red Clover Mixtures)

  • 이형석;이인덕
    • 한국초지조사료학회지
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    • 제14권4호
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    • pp.295-306
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    • 1994
  • The object of this experiment was to suggest the suitable cutting frequency and cutting height for orchardgrass (0G)-red clover(RC) mixtures under the intensive system of short-term pasture utilization. The fields trials were conducted over 3-year period(1991-1993) to evaluate dry matter yield, botanical composition, chemical composition and CP, DDM yield on the cutting frequency (30, 40 and 50 days) and cutting height(5, 7 and 9cm) With decreasing the cutting frequency, the DM yield of OG in the OG-RC mixtures was significantly increased(P

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지역냉방 시스템용 판형 열교환기의 주름높이에 따른 열전달 및 압력강하 특성 (Heat Transfer and Pressure Drop Characteristic of Plate Heat Exchanger with Corrugation Height for District Cooling System)

  • 권오경;김현중
    • 한국지열·수열에너지학회논문집
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    • 제7권2호
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    • pp.23-29
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    • 2011
  • The objectives of this paper are to study the characteristics of heat transfer and pressure drop of the plate heat exchanger with corrugation height by numerical analysis. Plate heat exchanger of three types was designed, which was corrugation height 3.1mm, 2.8mm and 2.5mm. The plate heat exchanger was numerically investigated for Reynolds number in a range of 950~3,380. The temperatures of the hot side were performed at $14.5^{\circ}C$ while that of the cold side was conducted at $4.5^{\circ}C$. The results show that the performance of heat transfer coefficient for corrugation height 2.5mm increases about 9.5~17.1% compared to that of corrugation height 3.1mm. On the other hand, the performance of pressure drop for corrugation height 2.5mm is remarkably higher than that of corrugation height 3.1mm, about 65.7~86.0%.

연속 입력된 영상을 이용한 높이 측정 (Height Measurement using the image sequences)

  • 김태은
    • 디지털콘텐츠학회 논문지
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    • 제7권1호
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    • pp.9-14
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    • 2006
  • 본 논문에서는 보안 시스템에서 사람 인식을 위한 중요한 단서 중의 하나인 사람의 키를 측정하는 알고리즘으로, 이미지 시퀀스에서 사람의 영역을 추출하고 기하학적 정보를 이용해 추출된 사람의 키를 측정하고자 한다. 이를 위해 단일 이동 물체 사람을 대상으로 하여 시퀀스 이미지에서 사람의 움직임 정보를 추출하고, 추출된 영역에서 수직히스토그램 투영을 하여 사람의 중심선을 찾아 머리와 발의 좌표점을 추출한다. 추출된 좌표점들은 소실점과 소실선의 기하학적 해석과 미리 입력한 다른 물체의 기준 높이를 가지고 실세계에서의 사람의 키를 측정하게 된다.

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카메라를 이용한 휴대폰 곡면유리의 높이측정 (Height Measurement of Cellphone Curved Glass using Camera)

  • 김한솔;이경준;정동연;이연형;김갑순
    • 제어로봇시스템학회논문지
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    • 제22권12호
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    • pp.1002-1010
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    • 2016
  • This paper describes the design of a cellphone curved glass measuring device using by camera. The measuring device was composed of two camera, two backlight system, a body and so on, and the program was made for a camera calibration and noise removal, and also the program was made for height measurement of a cellphone curved glass using by subpixel algorism. And then a new technique for measuring the height of the cell phone curved glass was proposed. The characteristics test of height measurement of gage blocks and cell phone curved glasses was carried out, the error of the height measurement of gage block is less than ${\pm}0.005$ and the error of the height measurement of the cell phone curved glasses is less than ${\pm}0.005$. Thus it thought that the designed cellphone curved glass measuring device and the new technique for measuring the height was used to measure the height of the cellphone curved glass.

슬러지계면층높이변화모델에서 컬럼높이에 대한 영향 (The Effect of Column Height on Sludge-Water Interface Height Change Model)

  • 박석균;강선홍
    • 상하수도학회지
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    • 제20권2호
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    • pp.265-272
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    • 2006
  • While sludge settles down in a column, sludge settling characteristic is influenced by effect parameters, interparticle force, wall effect etc. As the height of a column changes, the settling velocity of sludge-water interface changes, too. At lower sludge concentration, particular effect was not observed by the difference of column height, however it was observed that settleability of sludge was greatly influenced by column height when sludge settling was poor or sludge concentration was high. It is therefore required to consider the effect of column height when the power model for sludge interface settling is established. In the tests, there was hardly any $SVI_{ts}$(SVI after "t" minutes) difference in each column after 10min at $1.5kg/m^3$ of sludge concentration. When sludge concentration was at $2.5kg/m^3$, $SVI_{ts}$ tended to be constant after 20min. At $3.5kg/m^3$, $SVI_{ts}$ increased to 30minuets. The purpose of this work is to establish the correction factor that is able to compensate the errors derived from each different height of column.

부력조정에 의한 외끌이기선저인망의 어획성능 개선 (Improvement of fishing efficiency of Danish seine to ratio of buoyancy by sinking force)

  • 이혜옥;이주희;권병국;김부영;김병수;유제범
    • 수산해양기술연구
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    • 제43권2호
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    • pp.87-100
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    • 2007
  • This study was carried out to offer fundamental data for improving the fishing efficiency of the Danish seine. The net height and the shape in the water was measured to analyze the efficiency of the existing Danish seine. And then, an improved fishing gear was developed based on the results and was tested in the field. Measuring devices were attached on center of a ground rope and a head rope. The net height is the spread distance between the ground rope and the head rope, which was measured on the different ratio of buoyancy. The results are obtained as follows. The net height estimated from the design plan of horizontal hanging ratio 0.40 in the existing Danish seine A and B estimated both 4.94m. The net height of the existing Danish seine A and B was respectively 1.8m and 2.3m, which form 36.4% and 46.2% of the net height estimated from the design plan. Buoyancy was changed as 79.5% and 96.2% relative to the sinking force in the existing Danish seine. The net height of 79.5% was 3.95m which increased to 80% of the estimated net height. The other shows the same result with the first case. It is not necessarily that the high buoyancy/sinking force ratio make the high net height, 80% is adequate as the buoyancy/sinking force ratio. In case of the improved Danish seine, the mean net height was about 5.0m, means 58.3% of estimated net height 8.58m.

한방병원에 내원한 팔 저림 환자들의 베개 높이 분석 (The Study on Pillow Height for Arm Paresthesia Patients)

  • 권헌준;김정섭;이종훈;장홍규;조성우
    • 한방재활의학과학회지
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    • 제24권3호
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    • pp.165-171
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    • 2014
  • Objectives This study was performed to analyze relationship between pillow height and patients of arm paresthesia. Methods The data were collected from December 2013 to April 2014. The subjects who visited in Korean Medical hospital for Arm paresthesia were 65. The pillow height was measured from the surface to occipital protuberance. And the angle of cervical spine was measured from the tragus to the acromion. Results 1. The average height of pillow was $5.36{\pm}2.37cm$, and the average of the angle of cervical spine was $18.62{\pm}8.94^{\circ}$. 2. Correlation and regression analysis were performed on the pillow height, the angle of cervical spine and paresthesia. There was a significant correlation between the pillow height and paresthesia (R=0.389). And it had correlation between the angle of cervical spine and paresthesia (R=0.269). 3. The regression analysis was used to determine the influence of elements. The pillow height can influence to the arm paresthesia. Conclusions Through this study, we found out significant relationship between pillow height, cervical angle and patients of arm paresthesia. This result suggests that the higher pillow height and cervical angle can cause the more painful arm paresthesia.