• Tribology and Lubricants
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• v.24 no.5
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• pp.228-233
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• 2008

In this study, the methodology for determination of shoulder height in the internal shape design of ball bearing using 3D contact analysis is proposed. The static analysis of a ball bearing was performed to calculate the distribution of applied contact load and angles among the rolling elements. From each rolling element loads and the contact geometry between ball and inner/outer raceway, 3D contact analyses using influence function are conducted. These methodology is applied to HDD ball bearing. A critical axial load and a critical shoulder height which are not affected by edge are calculated. The proposed methodology may be applied to other rolling element bearing for the purpose of reducing the material cost and improving the efficiency of the bearing design process.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2004.08a
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• pp.320-324
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• 2004

• The Korean Journal of Physiology
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• v.1 no.1
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• pp.121-130
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• 1967

Determination of weekly and daily energy expenditure was made on 62 Republic of Korea Army cadets who were selected at random in order to estimate the weekly and daily ealorie expenditure. Basal metabolic rate (B.M.R.), and energy cost of various military and daily activities were measured by indirect calorimetry using open circuit method. Time-motion studies were also carried on using a stop-watch. The total weekly energy expenditure was calculated by summation of data using energy cost per minute, and the time spent on each activity. Determination of daily energy expenditure was deduced from each data of weekly energy expenditure. Food survey was also carried on for a week, and daily calorie intake was determined by a weekly average discounting loss in cooking. All measurements were determined from the Standard Table of Food Composition published by the Ministry of National Defense (1961). Following data were observed. 1. Physical status of cadets are as follows. Please note that the height and weight averages are 1-2cm and 4-5kg respectively over that of the Seoul National University students. First year Height 167.92 cm $(S.D.{\pm}4.09)$ Weight 61.72 kg $(S.D.{\pm}4.53)$ Second year Height 167.89 cm $(S.D.{\pm}3.46)$ Weight 63.01 kg $(S.D.{\pm}4.61)$ Third year Height 168.15 cm $(S.D.{\pm}4.24)$ Weight 43.48 kg $(S.D.{\pm}5.03)$ Fourth year Height 168.10 cm $(S.D.{\pm}3.70)$ Weight 64.02kg $(S.D.{\pm}5.10)$ 2. The B.M.R. of cadets averaged $36.57\;Cal./m^2/hr.(S.D.{\pm}3.63\;Cal./m^2/hr.)$ is almost equal with data on the same ages of civilians and the Japanese, but a lower average of $5.1\;Cal./m^2/hr.$ than that of a common soldier. 3. The energy expenditure during various military activities is close agreement with Consolazio. Passmore and Durnin, and Japanese reports.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.73-82
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• 2021

According to the government's announcement of the safety management enhancement policy for small and medium-sized private construction sites, the subject of mandatory CCTV installation has been expanded from large construction sites to small and medium-sized construction sites. However, since the existing CCTV at construction sites has been used for simple control for safety management, so research is needed for monitoring of construction sites. Therefore, in this study, three vanishing points were calculated based on a single image taken with a monocular camera, and then a camera matrix containing interior orientation parameters information was determined. And the accuracy was verified by calculating the height of the target object from the height of the reference object. Through height determination experiments using vanishing points based on a monocular camera, it was possible to determine the height of target objects only with a single image without separately surveying of ground control points. As a result of the accuracy evaluation, the root mean square error was ±0.161m. Therefore, it is determined that the progress of construction work at the construction sites can be monitored through the single image taken using the single camera.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.431-440
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• 2005

Location, height and clear-length of individual tree can be measured directly by LiDAR Remote Sensing, and dbh(diameter at breast height) can be estimated indirectly by tree height measured by LiDAR. In addition, stand volume and stand biomass are computed from estimated growth factors. In this study, each estimated growth factor was compared to the field measurements to validate accuracy. The coefficient of determination of total tree heights was 0.66 for total trees, 0.68 for Pinus koraiensis, 0.66 for Larix leptolepis and 0.60 for Quercus spp. The coefficient of determination of clear-length was 0.79 for total trees, 0.73 for Pinus koraiensis, 0.79 for Larix leptolepis, 0.68 for Quercus spp. The coefficient of determination of dbh predicted was 0.73 for Pinus koraiensis, 0.73 for Larix leptolepis and 0.85 for Quercus spp. Moreover The coefficient of determination of basal area was 0.82 for Pinus koraiensis, 0.92 for Larix leptolepis and 0.95 for Quercus spp. Biomass per ha computed by growth factor using LiDAR was 40,306 dm/ha for Pinus koraiensis, 94,150 tdm/ha for Larix leptolepis and 94,481 tdm/ha for Quercus spp. by species.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.237-244
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• 1995

In this study, we made WGS84 geoidal height model from GPS measurements for bench marks and calculated geoidal height of B.Ms which were selected check points using the hi-linear, trend surface fitting and triangulation interpolation method. From these, the interpolation accuracy was studied. Also, we tried to study accuracy of height transformation by making up orthometric height with latitude and longitude on Bessel ellipsoid for bench marks which were calculated by applying transformation parameters that were got GPS measurements for precise primary control stations. As a result of this study, the WGS84 geoidal height and orthometric height could be determined as a deviation value of 20 cm.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.169-177
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• 1997

An experimental study has been conducted at an intermediate scale to study the effect of a cross flow on a purely buoyant fire. Video taping of the flame and post processing of the images by means of a novel technique provide a contour of a mean flame for all cases studied. This flame contour allows the determination of a mean flame length and a mean flame height. The mean flame length and height are recorded as functions of the forced flow velocity. Three dimensional flow patterns are formed in the flame trailing edge affecting both the mean flame length and height. The three dimensional patterns are studied systematically as functions of the cross flow velocity to quantify the effect of confinement on the flame geometry.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.5
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• pp.183-190
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• 1993

Determining accurate geoid height is very important because it is the basis of the 3-D coordinate transformation and determination of the orthometric height. In this study, for determining the geoid height, bi-linear method grounded on the interpolation method, GPS leveling and OSU91A was applied to the $5km{\times}5km$ area and $60km{\times}60km$ area in the latitude $N\;36^{\circ}{\sim}37^{\circ}$ and the longitude $E\;127^{\circ}{\sim}128^{\circ}$. The results obtained by these methods were compared with conventional leveling data. In case of bi-linear method, it was dependent upon the shape of interpolation network and undulation of ground. If leveling data are satisfactory, GPS leveling is more proper than any other method. Also, it is 62 cm that an average difference of GPS leveling and OSU91A. As a result, in order to determine more precise geoid height, the development of local geoid model is a pressing problem to be solved. The result of the research will provide reference data for settling the 3-D coordinate transformation, and it is expected that it will also be applied to determination of 3-D position.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.3
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• pp.236-241
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• 2006

Monitor height is one of the key factors in the VDT workstation design. Most of the previous studies have focused on traditional VDT workplace where the operators performed data entry or word processing tasks using single monitor. This study aimed to suggest proper monitor height when the main task was monitoring information from different number of information sources. Twelve male students participated in three experiments: single information source (one monitor), two information sources (one monitor and one CCTV), and three information sources (one monitor, one CCTV and a window). Subjects performed monitoring tasks for 10 minutes with 3 different monitor center heights : 89.0 cm (Low), 111.3 cm (Middle), and 124.8 cm (High). Surface EMG signals of five neck muscles, subjective discomfort ratings, preference, and working postures were recorded. Results indicated that the middle height was proper for one monitor condition, but the low monitor height was recommended for more than two information sources.

• The Journal of Pediatrics of Korean Medicine
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• v.25 no.3
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• pp.57-69
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• 2011

Objectives: Purpose of this study is to analyze and to estimate which and how much genetic and environmental factors have affected on growth. Also, a method of final height prediction can be developed from this study results. Methods: Correlation analysis and categorical regression analysis were conducted between genetic and environmental factors correlated with the final adult height, through survey from 171 male. Results: Mid parental height, neonatal body weight, intake frequency of beef, chicken, milk, fruits and coffee, sleep quantity and quality during the elementary school and sleep quantity during the middle school have affected on the final adult height. And a regression equation with 0.494 for coefficient of determination was obtained. Conclusions: Mid-parental-height has the most affected on the final adult height. Among environmental factors, food and sleep have significantly affected, but exercise doesn't. Among foods, meal, beef, and milk intake have remarkably affected on the final height, and chicken and fruit also have affected in some degree, but coffee has affected badly. Among sleep habits, sleep quantity during the elementary school has the most affected, sleep quality during the elementary school and sleep quantity during the middle school also have affected in some degree on final height. The younger the age is, the more sleep have affected and sleep quantity have more affected than sleep quality. Neonatal weight also has remarkably affected on the final height. Through this analysis, the final adult height can be predicted using regression equation which covers 49.4% of genetic and environmental factors.