• The Korean Journal of Physiology
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• v.2 no.1
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• pp.31-38
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• 1968

Total body fat measurement by means of skinfold thickness was performed in 94 secondary school boys. Hydrostatic weighing was made on the same subject and corrected for residual volume in lung. Skinfold thicknesses at four sites, namely, back, waist, arm and abdomen, were compared with total body fat calculated from the equation given by Keys and Brozek and regression equation were computated. In 48 middle school boys aged between 13 and 16 years and 46 high school boys aged between 16 and 19 years, skinfold thicknesses increased at all 4 sites as age increased. The body density, however, showed different pattern. In middle school ages, body density showed little variation. Density in 13-14 years was 1.0608, in 14-15 years 1.0578 and in 15-16 years 1.0546. In high school ages density in-creased abruptly to 1.0703 (16 yr.), 1.0730 (17 yr.) and 1.0740 (18 yr.). Subsequently 15 years was a boundary for density change and total body fat change. In middle school boys as a group of 48 the observed values were: density: 1.0562, total body fat: 15.9%, mean skinfold thickness at four sites: 6.02 mm. The coefficient of correlation between mean skinfold thickness and density were r=-0.759 and r=0.781 with %fat. The regression equations were : Body $density=-0.00527{\times}Mean$ skinfold thickness (mm)+1.0879, %Fat=$1.933{\times}Mean$ skinfold thickness (mm)+4.26 In high school boys the values were: density: 1.0723, body fat: 10.4%, and mean skinfold thickness: 7.89 mm. Coefficients of correlation between mean skinfold thickness and density were r=-0.868 and r=0.855 with % fat. Thus, Body density=$-0.00365{\times}Mean$ skinfold thickness (mm)+1.1008, and %Fat=$1.326{\times}Mean$ skinfold thickness (mm)-0.064, were obtained. Although skinfold thicknesses at 4 sites showed a continuous increase in absolute value as age increased, relative growth of skinfold at specific site differed. On arm the growth of skinfold showed a decrease and on waist it showed an increase as compared to the mean thickness.

• Journal of the Korean Geosynthetics Society
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• v.17 no.2
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• pp.33-40
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• 2018

Characteristics of interface friction between cohesionless soils and geotechnical structure surfaces play an important role in the analysis of earth load and resistance on the structure. In general, geotechnical structures are mainly composed of either steel or concrete, and their surface roughnesses with respect to soil particle sizes influence the interface characteristics between soils and the structures. Accurate assessment of the interface friction characteristics between soils and structures is important to ensure the safety of geotechnical structures, such as mechanically stabilized earth walls reinforced with inextensible reinforcements, piles embedded into soils, retaining wall backfilled with soils. In this study, based on the database of high quality interface friction tests between frictional soils and solid surfaces from literature, equation representing peak interface friction angle is proposed. The influential factors of the peak interface friction angle are relative roughness between soil and solid surface, relative density of frictional soil, and residual (constant volume) interface friction angle. Futhermore, for the developed equation of the interface friction angle, its uncertainty was assessed statistically based on Goodness-of-fit test results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.363-363
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• 2008

The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

• Tuberculosis and Respiratory Diseases
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• v.42 no.2
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• pp.218-225
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• 1995

Background: Airway resistance(Raw) is measured with the body plethysmograph by displaying the relationship between airflow and alveolar pressure($V/P_A$). If the resistance curve on $V/P_A$ tracing is curved or looped, the estimation of Raw is difficult. This study was designed to examine wheather there is any correlation between the shape of resistance curve and the clinical status and the pulmonary function of patients. Methods: The 146 pulmonary disease patients with increased Raw were included in this study. The shapes of resistance curves on $V/P_A$ tracing with body plethysmograph during quiet breathing were analyzed and compared with pulmonary function. Results: The results were as follows ; 1) The shapes of resistance curves were summarized in 5 categories; type 1: linear, type 2: ovoid, type 3: sigmoid, type 4: scoop, type 5: paisley. The type 3 except 1 case, type 4 and type 5 were found to have loop mainly in expiratory phase. 2) Although the shapes of resistance curves were not typical for specific disease, the resistance curves of acute disease tended to belong to type 1 or 2 and those of chronic airflow obstruction tended to belong to type 3, 4 or 5. But resistance curves of bronchial asthma and destructive lung with tuberculosis showed all types in proportion to degree of airflow obstruction or destruction of parenchyme. 3) In the cases of resistance curves going to type 5 rather than type 1 and those with looping, airflow obstuction tended to be severe and airway resistance and residual volume tended to increase. Conclusions: Analysis of resistance curve on $V/P_A$ tracing measuring airway resistance is helpful for judging degree of airflow obstruction and air trapping. Although the shape of resistance curve is not typical for specific disease, there is a close association between looping and airway obstruction.

• Journal of Oral Medicine and Pain
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• v.26 no.4
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• pp.331-343
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• 2001

Advances in medical procedures and utilization of medication have resulted in expanding aged population, which leads to increased aged patients with salivary hypofunction and its associated symptoms in dental clinic. The purpose of this study was to investigate clinical characteristics of patients with dry mouth and its correlation with their salivary flow rate. Forty dry mouth patients (7 males, 33 females, mean age 42.0 years) whose flow rate of unstimulated whole saliva was less than 0.15 ml/min were included and their gender- and age-matched controls (7 males, 33 females, mean age 42.9 years) who did not report any complaints, suggestive of salivary gland dysfunction and had the flow rate of greater than 0.20 ml/min were included for comparison. The salivary flow rate was measured in both unstimulated and stimulated conditions. Dry mouth-related clinical information including history, dry mouth associated symptoms, exacerbating and relieving factors, drugs, systemic diseases, and family history was investigated using questionnaires. The differences in distribution of patients and control subjects to each question and their relation to the salivary flow rate were analyzed and we came to following conclusions. 1. There were statistically significant differences in the distribution of patients and controls to the following questions: the period and frequency of suffering from dry mouth; severity of dry feeling during a meal; severity of discomfort during swallowing; necessity of sipping liquids during swallowing dry foods, severity of discomfort in usual life due to dry feeling; self-assessment of residual salivary volume; taking medications. 2. The patients had more stress-related medical histories including indigestion, insomnia, and gastritis compared with controls. The patients took many kinds of medications to control their systemic diseases. 3. There were statistically significant differences in the salivary flow rate between different groups of patients to following questions: severity of dry feeling during a meal; severity of discomfort during swallowing; necessity of sipping liquids during swallowing dry foods. The difference was more significant in the case of stimulated salivary flow rate rather than unstimulated one. 4. The salivary flow rate of patients taking medications was significantly less than that of patients who did not take medications. The difference was more significant in the case of stimulated salivary flow rate rather than unstimulated one.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.1
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• pp.20-35
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• 2017

In the case of the seabed around and under gravity structures such as submerged breakwater is exposed to a large wave action long period, the excess pore pressure will be significantly generated due to pore volume change associated with rearrangement soil grains. This effect will lead a seabed liquefaction around and under structures as a result of the decrease in the effective stress, and eventually the possibility of structure failure will be increased. The study of liquefaction potential for regular waves had already done, and this study considered for irregular waves with the same numerical analysis method used for regular waves. Under the condition of the irregular wave field, the time and spatial series of the deformation of submerged breakwater, the pore water pressure (oscillatory and residual components) and pore water pressure ratio in the seabed were estimated and their results were compared with those of the regular wave field to evaluate the liquefaction potential on the seabed quantitatively. Although present results are based on a limited number of numerical simulations, one of the study's most important findings is that a safer design can be obtained when analyzing case with a regular wave condition corresponding to a significant wave of the irregular wave.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.182-192
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• 2008

In oder to develop a decision supporting system for oil spill response, the prototype of pollution response support system which has integrated oil spill prediction system and pollution risk prediction system has developed for Incheon-Daesan area. Spill prediction system calculates oil spill aspects based on real-time wind data and real-time water flow and the residual volume of spilt oil and spread pattern are calculated considering the characteristic of spilt oil. In this study, real-time data is created from results of real-time meteorological forecasting model(National Institute of Environmental Research) using ftp, real-time tidal currents datasets are built using CHARRY(Current by Harmonic Response to the Reference Yardstick) model and real-time wind-driven currents are calculated applying the correlation function between wind and wind-driven currents. In order to model the feature which is spilt oil spreading according to real-time water flow is weathered, the decrease ratio by oil kinds was used. These real-time data and real-time prediction information have been integrated with ESI(Environmental Sensitivity Index) and response resources and then these are provided using GIS as a whole system to make the response strategy.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.12
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• pp.1273-1280
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• 2008

This study sought to establish the optimum operating condition for the recovery of caustic (NaOH) solution from mercerization in textile process. As main factors, the silt density index (SDI) evaluation of ceramic membrane for the application of nanofiltration/reverse osmosis (NF/RO) membrane, the recovery yield measurement of caustic solution for the application of polymeric membrane, the optimum condition of chemical cleaning for the membrane regeneration, the optimum removal condition of total organic carbon (TOC), turbidity, color, and the permeate flux of ceramic membrane/polymeric membrane combined process were investigated. As results, ceramic ultrafiltration (UF) in the first step and nanofiltration (NF) in the second step were found to be suitable for the removal of total suspended solid (TSS), residual organics, turbidity including color, and the recovery of caustic solution from caustic wastewater stream in mercerization process. When only the ceramic UF membrane was used, the rejection efficiency of both of TSS and turbidity was more than 99.0%, and the color and TOC were rejected about 74.7% and 49.2%, respectively. Meanwhile, the combined membrane precess of UF and NF membranes showed even more efficient removal abilities and thus more than 99.9% of TSS and turbidity, 87.7% of color, and 78.2% of TOC were removed. In particular, 91.3% of NaOH was successfully recovered with 83.7% of total volume in the combined membrane process. With this regard, a clean caustic solution was obtained in a high purity, which can be reused for mercerization process, expecting to offer economical benefits.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.6
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• pp.521-530
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• 2020

Purpose: Malnutrition is a common feature in critically ill children. Enteral nutrition (EN) is the main strategy to nutritionally support critical ill children, but its use can be hindered by the development of intolerance. The study aimed to assess the effectiveness and safety of amoxicillin/clavulanate (A/C) to treat EN intolerance. Methods: We retrospectively evaluated patients admitted to the pediatric intensive care unit from October 2018 to October 2019. We conducted a case-control study: in the first 6 months (October 2018-April 2019) we implemented the nutritional protocol of our Institution with no drug, whereas in the second half (May 2019-October 2019) we employed A/C for 1 week at a dose of 10 mg/kg twice daily. Results: Twelve cases were compared with 12 controls. At the final evaluation, enteral intake was significantly higher than that at baseline in the cases (from 2.1±3.7 to 66.1±27.4% of requirement, p=0.0001 by Wilcoxon matched-pairs signed rank test) but not in the controls (from 0.2±0.8 to 6.0±14.1% of the requirement, p=NS). Final gastric residual volume at the end of the observation was significantly lower in the cases than in the controls (p=0.0398). The drug was well tolerated as shown by the similar safety outcomes in both cases and controls. Conclusion: Malnutrition exposes critically ill children to several complications that affect the severity of disease course, length of stay, and mortality; all may be prevented by early EN. The development of intolerance to EN could be addressed with the use of A/C. Future prospective clinical trials are needed to confirm these conclusions.

• Journal of Chest Surgery
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• v.46 no.5
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• pp.340-345
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• 2013

Background: This study aims to evaluate whether or not the method of right vertical axillary minithoracotomy (RVAM) is preferable to and as reliable as conventional sternotomy surgery, and also assesses its cosmetic results. Methods: Thirty-three patients (7 males, 26 females) with atrial septal defect were admitted to the Cardiovascular Surgery Clinic of Cukurova University from December 2005 until January 2010. The patients' ages ranged from 3 to 22. Patients who underwent vertical axillary minithracotomy were assigned to group I, and those undergoing conventional sternotomy, to group II. Group I and group II were compared with regard to the preoperative, perioperative and postoperative variables. Group I included 12 females and 4 males with an average age of $16.5{\pm}9.7$. Group II comprised 14 female and 3 male patients with an average age of $18.5{\pm}9.8$ showing similar features and pathologies. The cases were in Class I-II according to the New York Heart Association (NYHA) Classification, and patients with other cardiac and systemic problems were not included in the study. The ratio of the systemic blood flow to the pulmonary blood flow (Qp/Qs) was $1.8{\pm}0.2$. The average pulmonary artery pressure was $35{\pm}10$ mmHg. Following the diagnosis, performing elective surgery was planned. Results: No significant difference was detected in the average time of the patients' extraportal circulation, cross-clamp and surgery (p>0.05). In the early postoperative period of the cases, the duration of mechanical ventilator support, the drainage volume in the first 24 hours, and the hospitalization time in the intensive care unit were similar (p>0.05). Postoperative pains were evaluated together with narcotic analgesics taken intravenously or orally. While 7 cases (43.7%) in group I needed postoperative analgesics, 12 cases (70.6%) in group II needed them. No mortality or major morbidity has occurred in the patients. The incision style and sizes in all of the patients undergoing RVAM were preserved as they were at the beginning. Furthermore, the patients of group I were mobilized more quickly than the patients of group II. The patients of group I were quite pleased with the psychological and cosmetic results. No residual defects have been found in the early postoperative period and after the end of the follow-up periods. All of the patients achieved functional capacity per NYHA. No deformation of breast growth has been detected during 18 months of follow-up for the group I patients, who underwent RVAM. Conclusion: To conclude, the repair of atrial septal defect by RVAM, apart from the limited working zone for the surgeon in these pathologies as compared to sternotomymay be considered in terms of the outcomes, and early and late complications. And this has accounted for less need of analgesics and better cosmetic results in recent years.