• Title/Summary/Keyword: Measure height

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A Study on function of Artificial Reef by Using Geotexile Tube (토목섬유를 활용한 인공리프의 기능에 관한 연구)

  • Shin, Moon-Seup;Ahn, Kyung-Soo;Shin, Eun-Chul
    • Journal of Korea Water Resources Association
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    • v.36 no.4
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    • pp.623-631
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    • 2003
  • A large scale hydrological laboratory model tests for the geotextile tube were conducted to investigate the stability of geotextile tube and the capability of breakwater with variations of significant wave height, percentage of soil filling, and the water level above geotextile tube. The sliding displacement of geotextile tube is measured to check the stability of geotextile tube for given the various significant wane heights. The marked mash was laid out at the bottom of water channel to measure the displacement of geotextile tube. The bench mark was furnished in the upper part of water channel and the initial location was marked every 10cm interval to measure the displacement of geotextile tube. The wane transmit ratios are analyzed with the variations of soil filling of tube and of the top crown height wave above the geotextile tube in order to study the performance of brekwater before and after the installation of geotextile tube.

Analysis of GPS Levelling in Small Area for Precise Leveling (정밀 수준측량을 위한 소규모 지역에서의 GPS 수준성과 분석)

  • 강준묵;임영빈;이은수;선재현
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.04a
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    • pp.51-55
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    • 2004
  • In this study, the levelling and the GPS levelling were carried out with 6 points in 2km${\times}$2km area and the results were analysed. As a result of this research, we had to observe more than 15 minutes to get the height accuracy of 10mm by single frequency GPS receiver in relative surveying. We could not get more better accuracy than 10mm. we could get the height accuracy of within 10mm from observing only more than 5 minutes by double frequency GPS receiver, and of within about 3mm from observing more than 10 minutes. When the number of fixed points is within 3, the level net adjustment result is very close to the one of direct levelling survey. When the number of fixed points is 3, the less the area of triangle the better the adjustment result, and the case of including measure point has more better accuracy than that of non-including measure point.

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A Study on the Recognition Method of the Stair Size for the Climbing Mobile Robot (이동 로보트의 계단 승월을 위한 계단 크기 인식 기법에 관한 연구)

  • 김승범;이응혁;김병수;김승호;민홍기;홍승홍
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.10
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    • pp.1269-1279
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    • 1995
  • A mobile robot in a nuclear power plant is usually needed to equip the ability of going up and down stairs for a some kind of inspection. For this purpose, it is necessary for the mobile robot to figure out the size of stairs laid on a navigation path to gurantee robot's moving freely. In this paper, to measure the size of stairs existing in front of a mobile robot we designed the stair size recognition unit which can measure the stair's height and width using an ultrasonic sensor and/or a CCD camera. Also to obtain higher reliability of ultrasonic sensing data we proposed the horizontal sensing method. On the assupmtions that the mobile robot generates a trajectory while ascending stairs, we simulated it on a IBM compatible computer. The result showed that the suggested method satisfied our purpose. In a stair size estimation, the detected stair's height error was about .+-.3mm, and width was about .+-.5mm.

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Design of a Mechanism to Increase Lateral Stability of Mobile Robot (이동로봇의 횡방향 안정성 증대를 위한 기구)

  • 정상국;최용제
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1148-1153
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    • 2004
  • This paper presents the mechanism to increase lateral stability of a mobile robot using an energy stability margin theory. Previous measure of stability used in a wheeled mobile robot has been based on a static stability margin. However, the static stability margin is independent of the height of the robot and does not provide sufficient measure for the amount of stability when the terrain is not a horizontal plane. In this work, the energy stability margin theory, which is dependent on robot's height is used to develop a 2 dof mechanism to increase lateral stability. This proposed mechanism shifts the center of gravity of the robot to the point where the energy stability margin is maximized and overall stability of the robot equipped with this mechanism will be increased.

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Prevalence of child malnutrition in agro-pastoral households in Afar Regional State of Ethiopia

  • Fentaw, Rabia;Bogale, Ayalneh;Abebaw, Degnet
    • Nutrition Research and Practice
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    • v.7 no.2
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    • pp.122-131
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    • 2013
  • Based on data generated from 180 randomly selected households with children age under five years old in Aysaita district of Afar region of Ethiopia, this study explored prevalence of malnutrition and scrutinized household characteristics, maternal characteristics, specifics of the child and economic variables associated with child malnutrition. The height-for-age Z-scores (HAZ), weight-for-height Z-scores (WHZ) and weight-for-age Z-scores (WAZ) were used to measure the extent of stunting, wasting and underweight, respectively. The results revealed that prevalence of long term nutritional imbalance and malnutrition status indicator (i.e. stunting) was 67.8%. The short term measure (wasting) was found to be 12.8% and underweight was found to be 46.1%. Moreover, children in households which are headed by women, and characterized by more dependency ratio, less access to assets, health services and institutions are more likely to be undernourished.

Analysis of the Individual Tree Growth for Urban Forest using Multi-temporal airborne LiDAR dataset (다중시기 항공 LiDAR를 활용한 도시림 개체목 수고생장분석)

  • Kim, Seoung-Yeal;Kim, Whee-Moon;Song, Won-Kyong;Choi, Young-Eun;Choi, Jae-Yong;Moon, Guen-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.5
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    • pp.1-12
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    • 2019
  • It is important to measure the height of trees as an essential element for assessing the forest health in urban areas. Therefore, an automated method that can measure the height of individual tree as a three-dimensional forest information is needed in an extensive and dense forest. Since airborne LiDAR dataset is easy to analyze the tree height(z-coordinate) of forests, studies on individual tree height measurement could be performed as an assessment forest health. Especially in urban forests, that adversely affected by habitat fragmentation and isolation. So this study was analyzed to measure the height of individual trees for assessing the urban forests health, Furthermore to identify environmental factors that affect forest growth. The survey was conducted in the Mt. Bongseo located in Seobuk-gu. Cheonan-si(Middle Chungcheong Province). We segment the individual trees on coniferous by automatic method using the airborne LiDAR dataset of the two periods (year of 2016 and 2017) and to find out individual tree growth. Segmentation of individual trees was performed by using the watershed algorithm and the local maximum, and the tree growth was determined by the difference of the tree height according to the two periods. After we clarify the relationship between the environmental factors affecting the tree growth. The tree growth of Mt. Bongseo was about 20cm for a year, and it was analyzed to be lower than 23.9cm/year of the growth of the dominant species, Pinus rigida. This may have an adverse effect on the growth of isolated urban forests. It also determined different trees growth according to age, diameter and density class in the stock map, effective soil depth and drainage grade in the soil map. There was a statistically significant positive correlation between the distance to the road and the solar radiation as an environmental factor affecting the tree growth. Since there is less correlation, it is necessary to determine other influencing factors affecting tree growth in urban forests besides anthropogenic influences. This study is the first data for the analysis of segmentation and the growth of the individual tree, and it can be used as a scientific data of the urban forest health assessment and management.

Changes of Lumbar Lordosis Caused by Different Heel Heights in Healthy Women (20대 정상성인의 구두굽 높이에 따른 요추전만도의 변화)

  • Yun, So-Young
    • Physical Therapy Korea
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    • v.6 no.2
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    • pp.43-55
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    • 1999
  • In today's society, many women wear high-heeled shoes, but the effect of heel height on lumbar lordosis has not been clearly defined. The objective of this study was to identify the influence of heel height and general characteristics of subjects on lumbar lordosis. The subjects of this study were 40 healthy women who were students of the Department of Physical Therapy, College of Rehabilitation Science, Taegu University. Flexible ruler measurement was used to measure the lumbar lordosis at barefoot, 3 cm and 7 cm high-heeled standing positions. The results were as follows: 1) Significant statistical decrease in lumbar lordosis was observed as heel heights were increased from barefoot to 7 cm high heel. 2) There were no statistically significant differences between lumbar lordosis according to three different heel heights and weight, body mass index. 3) Lumbar lordosis measured at different heel heights was related to subject's height. With increasing subject's height, lumbar lordosis that measured from each heel height was significantly decreased. As heel heights were increased from barefoot to 7 cm high heel, significant statistical decrease in lumbar lordosis was observed in the subjects whose height were 151~160 cm. 4) Intrarater reliability on lumbar lordosis taken with a flexible ruler was good, with Cronbach ${\alpha}$ values of 0.8971 for barefoot, 0.8107 for 3 cm and 0.9002 for 7 cm high-heeled standing positions.

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Improvement of Vehicle Classification Method using Vehicle Height Measurement (차량높이 계측을 통한 차종분류 향상 방안 연구)

  • Oh, Ju-Sam;Jang, Kyung-Chan;Kim, Min-Sung
    • International Journal of Highway Engineering
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    • v.12 no.4
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    • pp.47-51
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    • 2010
  • A vehicle classification data is essential for traffic road planning and pavement. In this study, the vehicle height, vehicle criteria for classification applied to measure the height of the car driving has devised a way to install equipment. It is capable of measuring the vehicle height was confirmed to field experiments, the measurement system is obtained to the vehicle length and height data. In this experiment, results showed the accuracy of 88.6% compared to classification data using the discriminant function obtained from video replaying. The height of vehicle applying the classification criteria can be utilized to determine the vehicle class.

Measurement Method of Airburst Height Using the Approach Angle (비행체 진입각을 이용한 공중 폭발고도 계측 방법)

  • Kim, Jinho
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.4
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    • pp.497-504
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    • 2017
  • This paper proposes a method to measure the airburst height by utilizing a high speed camera. This method might be applied to the test of which flight target is alive after the burst. The proposed method consists of four main steps. The first step is to compute the impact point using the sea surface height. The second step is to compute the height of burst (HOB) by using the distance from the camera to the impact point. This could be different from the real explosion height. That is because the distance from the camera to the burst point is not the same as it from the camera to the impact point. Therefore, the third step is to calculate the approach angle of the flight target with respect to the installed camera. Then, the last step is to compensate the computed height by using the approach angle. The result of the proposed method is compared with it from the triangulation. In this paper, the HOB error is also analyzed regarding the approach angle difference. Based on this analysis, the camera position might be suggested for error reduction.

Using Ultrasonography Measurements to Determine the Depth of the GB 21 Acupoint to Prevent Pneumothorax

  • Chen, Hsiao-Neng;Chang, Chau-Yi;Chen, Lian-Zen;Chang, Yu-Jun;Lin, Jaung-Geng
    • Journal of Acupuncture & Meridian Studies
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    • v.11 no.6
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    • pp.355-360
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    • 2018
  • Introductions: Pneumothorax is the most frequent severe acupuncture-related adverse event occurring at the GB 21 acupoint. This study used ultrasonography (US) to measure the depth of the GB 21 acupoint in adults and assessed its applicability for ensuring safe acupuncture practices. Materials and methods: A US probe was used to measure the vertical depth from the skin to the pleural line of the apex of the lungs at the right and left GB 21 acupoints. The sex, age, body weight, height, and body mass index of each person were recorded. Student t test and generalized estimating equations were used for statistical analysis. Results: Sixty women and 41 men with a median age of 29 years were included in this study. The depth of GB 21 increased with body weight, height, and body mass index (p < 0.001). The mean depth of GB 21 in men (17.4 mm) was greater than that in women (14.6 mm; p < 0.001). The depth difference between the right and left shoulders was significant in men (p < 0.001) but not in women. Conclusions: US can be used to measure GB 21 acupoint depth. Further control studies on its use to ensure safe clinical practices, including preventing acupuncture-related pneumothorax, are warranted.