• Fire Science and Engineering
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• v.32 no.3
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• pp.42-50
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• 2018

The effect of sub-grid turbulence and combustion models on the mean flame height in a heptane pool fire according to the Fire Dynamics Simulator (FDS) version (5 and 6) based on Large Eddy Simulation (LES) was examined. The heat release rate for the fire simulation was provided through experiments performed under identical conditions and the predictive performance of the mean flame height according to FDS version was evaluated by a comparison with the existing correlation. As a result, the Smagorinsky and Deardorff turbulence models applied to FDS 5 and 6, respectively, had no significant effects on the mean flow field, flame shape and flame height. On the other hand, the difference in pool fire characteristics including the mean flame height was due mainly to the difference in the mixture fraction and Eddy Dissipation Concept (EDC) combustion models applied to FDS 5 and 6, respectively. Finally, compared to FDS 6, FDS 5 provided the predictive result of a significantly longer flame height and more consistent mean flame height than the existing correlation.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.216-221
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• 2001

In this paper, statistical properties of waves in the sea area of Pohang, Korea are examined absed on 1998-1999's wave data from directional wave buoy which is located Pohang(Janggigog). Wave data aquisition rate, monthly maximium, minimum and mean wave heights, frequency of wave direction are summarized. Wave height and period scatter diagrams and n-year return period wave heights are estimated. Wave periods of maximum wave heights are also estimated.

• Journal of Korean Neurosurgical Society
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• v.52 no.4
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• pp.365-371
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• 2012

Objective : To document lumbar lordosis (LL) of the spine and its change during surgeries with the different height but the same angle setting of the anterior cage. Additionally, we attempted to determine if sufficient LL is achieved at different cage heights and to quantify the change in LL during multi-level anterior lumbar interbody fusion (ALIF). Methods : The medical records and radiographs of 42 patients who underwent more than 2 level ALIFs between 2008 and 2009 were retrospectively reviewed. We evaluated 3 parameters seen on lateral whole spine radiographs : LL, pelvic incidence (PI), and sagittal vertical axis (SVA). The mean follow-up time was 28.1 months and the final follow-up radiographs of all patients were reviewed at least 2 years after surgery. Statistical analysis was performed using the paired t-tests. Results : Lumbar lordosis had changed up to 30 degrees immediately and 2 years after surgery (preoperative mean LL, SVA : 22.45 degrees, 112.31 mm; immediate postoperative mean LL, SVA : 54.45 degrees, 37.36 mm; final follow-up mean LL, SVA : 49.56 degrees, 26.95 mm). Our goal of LL is to obtain as much PI as possible, preoperative mean PI value was $55.38{\pm}3.35$. The pre-operative and two year post-surgery follow-up mean of the Japanese Orthopedic Association score were $9.2{\pm}0.6$ and $13.2{\pm}0.6$ (favorable outcome rate : 95%), respectively. In addition, we were able to obtain good clinical outcomes and sagittal balance with a subsidence rate of 22.7%. Conclusion : We were able to achieve sufficient LL, such that it was similar to the PI, utilizing multi-level ALIF with the use of a tall cage with the same angle setting of the cage. We have found out that achieving sufficient lumbar lordosis and sagittal balance require an anterior lumbar cage with high angle and height.

• The Journal of Pediatrics of Korean Medicine
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• v.25 no.1
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• pp.49-62
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• 2011

Objectives: The purpose of this study is to evaluate the effect of the herbal medicine in children's growth. Methods: 67 of the children in the age from 3 to 16 were participated in this study(31 of boys and 36 of girls). Department of the pediatrics, $\bigcirc\bigcirc$ university oriental medical hospital, and the participants were measured their body composition and their bone age, the height percentile of the first and the last visit were measured, and those were compared by the Korean Association of Pediatrics' Growth Statistics Curve. Results: 1. Generally, total children's average height and weight were significantly increased after the herbal medical treatment. The comparison between the height and the average height, the weight and the average weight were significantly decreased after the herbal medical treatment. 2. Total children's average soft lean mass, body fat mass, BMI, basal metabolic rate, abdominal circumference and hip circumference were also significantly increased after the herbal medical treatment. 3. The mean height percentile of the children showed 0.88 percentile upwardly. The mean weight percentile of children showed 1.84 percentile upwardly. 4. The height percentile was increased in the group of boys younger than 13, and a group of girls older than 12 year old. Other than a group of boys older than 14, every group showed increasing weight percentile. Conclusions: The herbal medical treatment helped children with growth retardation.

• Journal of Trauma and Injury
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• v.18 no.2
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• pp.101-106
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• 2005

Purpose: The number of the deceased from free-fall is increasing nowadays. Free-fall comes to a great social problem in that even the survivor will be suffering for cord injury or brain injury, and so on. We analyzed the cases of free-fall patients to find out whether the injury severity is mainly correlated with the height of fall. Methods: We retrospectively investigated the characteristics of patients, who fall from the height above 2m from January 2000 to August 2004. We excluded the patients who transferred to other hospital, transferred from other hospital, and not known the height of fall. 145 patients were evaluated. Variables included in data analysis were age, height of fall, injury severity score (ISS), the being of barrier, and the survival or not. To find out the correlation between height of fall and death, we used receive operating characteristics (ROC) curve analysis. Results: The mean age of patients was $36.5{\pm}19.4$ years old. 110 were male and 35 were female. Mean height of fall was $11.1{\pm}8.5m$. 51 patients (35.2%) were died and 30 patients of them (58.9%) got emergency room on dead body. The mean height of fall is $8.9{\pm}5.8m$ for 94 survivors and $15.2{\pm}11.0m$ for the 51 deceased (p<0.001). The area under the ROC curve was 0.646, which means the height of fall was not adequate factor for predicting for death. At 13.5m, as cut?off value, sensitivity is 52.9%, specificity is 86.2%, positive predictive value is 67.5% and negative predictive value is 77.1%. There were statistical differences in mortality rate and ISS between 'below 13.5m group' and 'above 13.5m group', but there was not statistical difference in head and neck AIS. Conclusion: The height of fall is not adequate factor for prediction of death. So other factors like intoxication or not, the being of barrier or protection device need to be evaluated for predicting of free-fall patient's death.

• Childhood Kidney Diseases
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• v.10 no.2
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• pp.219-227
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• 2006

Purpose : We aim to identify the clinical and demographic characteristics in children who underwent renal transplantation(RTx) and to evaluate the influence on growth of RTx in children. Methods : We reviewed 17 medical records of chronic renal failure patients who underwent RTx from April 1992 and June 2004 at Busan Paik Hospital. Age and sex distribution, cause of disease, donor analysis, patient and graft survival rate, and the status of growth after RTx were analysed by retrospective study. Results : Eighteen RTx were performed in 17 patients(8 boys, 9 girls). The mean age at the time of RTx was $15.8{\pm}3.5$ years and the mean duration of dialysis therapy before RTx was $22.4{\pm}18.0$ months. The 1 year and 5 year patient survival rate were each 100%, and the 1 year and 5 year graft survival rate were 88%, 36% respectively. The most common cause of graft failure was chronic rejection. The mean final height of male patients was $162.8{\pm}10.0$ cm(143.0-172.5 cm) and of female patients was $154.5{\pm}12.1$ cm(135.8-160.0 cm). The mean height standard deviation score(Ht SDS) increased after RTx from -1.95 to -1.53 but the increment rate was not statistically significant. Similar changes were noted in individual patient analysis. Also there was no significant difference between the living-related donors and cadaveric donors. Conclusion : Our data shows that even successful RTx rarely results in full growth rehabilitation. To overcome retarded growth in children with chronic renal failure, appropriate combined management of metabolic and nutritional problems, correction of anemia, proper use of recombinant growth hormone therapy, early renal transplantation and shortening of the duration of dialysis would be necessary.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.286-293
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• 2005

An interpretation on the solid circulation characteristics in a fluidized-bed process has been carried out as a first step to simulate the dry entrained-bed absorption and bubbling-bed regeneration system for $CO_2$ removal from flue gas. A particle population balance has been developed to determine the solid flow rates and particle size distributions in the process. Effects of principal process parameters have been discussed in a laboratory scale process (absorption column: 25 mm i.d., 6 m in height; regeneration column: 0.1 m i.d., 1.2 m in height). The particle size distributions in absorption and regeneration columns were nearly the same. As gas velocity or static bed height in the absorption column increased, soild circulation rate and feed rate of fresh sorbent increased, however, mean particle diameter decreased in the absorption column. As cut diameter of the cyclone of the absorption column increased, solid circulation rate decreased, whereas feed rate of fresh sorbent and mean particle diameter in the absorption column increased. As attrition coefficient of sorbent particle increased, solid circulation rate and feed rate of fresh sorbent increased but mean particle diameter in the absorption column decreased.

• The Korean Journal of Physiology
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• v.5 no.2
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• pp.15-27
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• 1971

Physiological analysis of the physical exercise was made on 9 subjects performing mountain climbing. The course between two points (256 and 516 meters altitude) was 1,300 meters in distance and difference of vertical height was 260 meters making the mean grade of 20%. In the field, the heart rates during uphill or downhill walk were recorded by EKG radio-telemetry. In the laboratory, oxygen consumption was obtained by the recorded heart rates, using individual heart rate vs oxygen consumption diagram obtained by treadmill test. the following results were obtained. 1. Uphill walk time was 36.5 minutes, and during this period the mean heart rate was 149.0 heats/min and peak heart rate was 169.2 beats/min. The total heart beats during the uphill walk was 5.433 beats. 2. The ratio of individual mean heart rate during the uphill walk to the maximal heart rate distributed between 66.6% and 98.3%, and the mean of the total group was 83.1%. The ratio of peak heart rate of uphill walk to the maximal heart rate was 94.5% in the group. Thus uphill walk of a 20% grade mountain course was an exhaustive exercise. 3. Oxygen consumption during uphill walk was 2.22 l/min (ranged between 1.79 and 2.70 l/min) and the ratio of this to the resting oxygen consumption was 8.31. The peak value of oxygen consumption during uphill walk was 2.73 l/min and the ratio of this to the resting oxygen consumption was 10.39. 4. Energy expenditure during uphill walk showed a mean of 11.1 kcal/min and the peak expenditure rate was 13.6 kcal/min. The total energy expenditure during 36.5 minutes of uphill walk was 396 kcal. 5. In downhill walk, the time was 31.7 minutes, mean heart rate was 118.4 (ranged between 100.1 and 142.7) beats/min, and the peak heart rate was only 129.4 beats/min. The ratio of mean heart rate to the maximal heart rate was 66.3%. Total heart beats during downhill walk was 3,710 beats. The ratio of downhill oxygen consumption to the resting consumption was 5.70. The rate of energy expenditure was 7.5 kcal/min, and the total onery expenditure during the 31.7 minutes of downhill walk was 228 kcal. 6. The effect of training was manifest in the uphill walk and not in the downhill walk. After training in mountain course walk, i) the uphill time was shortened, ii) mean heart rate increased, iii) time vs heart rate curve became smooth and showed less frequent zig-zag, i.e., the depth of trough on the curve decreased and the magnitude was less than 10 beats. In non-trained subject the depth of trough on the curve was greater than 50 beats and appeared more frequently. 7. Mountain climbing is a good health promotion exercise. For the promotion of health the reasonable amount of uphill mountain walk exercise in a 20% grade course is a walk for 40 or 50 minutes duration once a week.

• Journal of Periodontal and Implant Science
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• v.37 no.2
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• pp.151-164
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• 2007

Objective: The sinus floor elevation procedures have been used to facilitate implant placement in the severely atrophic posterior maxilla. Many variables may have an influence on the outcomes of the sinus floor elevation in combination with implant treatment. The aim of this study was to analyze survival rate of implants placed in the edentulous maxillae of patients in whom sinus floor elevation was undertaken according to variables. Materials and Methods: It consisted of 96 patients(50 male and 46 female), ranging in age from 31 to 70 years(mean 49 years), who underwent sinus floor elevation procedure(94 implants in left side and 106 implants in right side) from 2001 to 2002. A total of 200 implants were placed in the grafted sinus(73 implants in lateral approach and 127 implants in crestal approach). All implants were restored by fixed prosthesis. All patients were healthy. Follow-up periods for implants were between 48 to 60 months. Results: The cumulative survival rate of implants was 91.5%. Gender, age and operation site did not have an influence on the survival rate. There was statistically significant differences for the implants which placed in less than 4 or 5 rom residual bone height, the survival rate was 60%, 81.4% respectively (p<0.05). There was no statistically significant difference of implants survival rate ac- cording to approach technique. The survival rate for 100% autogenous bone grafts was lower with respect to composite grafts containing autogenous bone and 100% substitutes. The survival rate for hydroxyapatite-coated implants was statistically significant lower than other textured group (p<0.05). Conclusion: Residual bone height, surface texture and graft materials have an influence on the survival rate. To use autogenous bone as a part of a composite bone replacement, implant texture which leads to more favorable implant-bone interface were necessary. To determine residual bone height for initial implant stability was important.

• Journal of the Korean Dietetic Association
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• v.2 no.2
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• pp.168-180
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• 1996

This study was accomplished to investigate the prevalence of obesity among the 229 elementary school children(boys; 115 persons, girls; 114 persons) during 4 years by retrospective study. The results were as follows; 1. The mean height and weight of 229 subjects were 143.2cm(boys;143.4cm, girls; 142.7cm), 38.8kg(boys;40.4kg, girls;36.9kg), respectively. And other anthropometric body index such as the mean BMI, Rohrer Index, WLI and Obesity Index of subjects were 18.8(boys;19.5, girls; 18.0), 1.31(boys;1.36, girls; 1.26), 115.5(boys;121.4, girls; 108.9) and 110.6(boys;114.5, girls; 106.7), respectively. 2. The mean percentile values of height and weight of subjects were higher than the '85 Korean Children's Growth Standard, respectively. In the case of boys, the 75th percentile value of weights was larger than that's 97th's. And in the case of girls, the 75th percentile value of weights was equalled to the that's 90th's. 3. When the subjects were classified into 4 groups such as obese, overweight, normal, and lean groups according to Obesity Index, their percentages were 28.8%(boys; 38.3%, girls; 19.3%), ll.8%(boys; 9.6%, girls; 14.0%), 50.7%(boys; 47.0%, girls; 54.4%) and 8.7%(boys; 5.2%, girls; 12.3%), respectively. And only I person(3.3%) is classified into normal group and 2 persons(6.7%) are classified into overweight group when they become 5 grade among 30 persons(13.1%) who were classified into obese group when they were I grade. 4. Changes in percentage of subjects differentiated by 3 indices during 4 years(from I grade to 5 grade) were as follows; In the case of BMI were 5.2%, 5.2%, 11.8%, 21.0%, 27.5%. In the case of Roher index were 13.1%, 11.8%, 14.4%, 14.8%, 17.8%. And in the case of WLI were 15.7%, 21.6%, 29.5%, 32.2%, 36.7%. 5. There was no significant difference among 4 groups on the skip rate of breakfast(obese;48.5%, overweight;55. mean meal time of subjects took about 10 minutes which was short, and the eating rate of obese group was significantly shorter than that of other groups(p<0.05). There was a tendency that the rate of the obese or overweight group eating together in breakfast and dinner was lower than that of normal or lean group. The mean T.V. watching time and the rate of eating out of subjects were 1-2 hours/day and 1 or 2 times/week. In conclusion, the subjects have been grown remarkably compared to the '85 Korean Children's Growth Standard, especially boy's weight. In order to the elementary school children to be grew as healthful citizen they should recognize the importance of meals of everyday, the balanced meals, and desirable eating habits. In addition to these, we should educate the ways of meal-life to them. We also are in need to develope the methods of education for the students themselves and their parents so that could prevent the increase rate of obesity.