• Journal of the Korean Society of Safety
• /
• v.11 no.4
• /
• pp.143-150
• /
• 1996

This is an explicit-Implicit, finite element analysis for linear as well as nonlinear hygrothermal stress problems. Additional features, such as moisture diffusion equation, crack element and virtual crack extension(VCE ) method for evaluating J-integral are implemented in this program. The Linear Elastic Fracture Mechanics(LEFM) Theory is employed to estimate the crack driving force under the transient condition for and existing crack. Pores in materials are assumed to be saturated with moisture in the liquid form at the room temperature, which may vaporize as the temperature increases. The vaporization effects on the crack driving force are also studied. The Ideal gas equation is employed to estimate the thermodynamic pressure due to vaporization at each time step after solving basic nodal values. A set of field equations governing the time dependent response of porous media are derived from balance laws based on the mixture theory Darcy's law Is assumed for the fluid flow through the porous media. Perzyna's viscoplastic model incorporating the Von-Mises yield criterion are implemented. The Green-Naghdi stress rate is used for the invariant of stress tensor under superposed rigid body motion. Isotropic elements are used for the spatial discretization and an iterative scheme based on the full newton-Raphson method is used for solving the nonlinear governing equations.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.6
• /
• pp.4125-4130
• /
• 2015

This paper presents the communication performance for the radiation pattern reconfigurable antenna in the wearable device measuring bio signal (temperature, blood pressure, pulse etc.) of human body. The operational frequency is 2.4 - 2.5 GHz, which covers Bluetooth communication bandwidth. The maximum gain of the antennas is 1.96 dBi. The proposed antenna is efficiently transmitting and receiving signal by generating two opposite beam directions using two RF switches (PIN diode). Also, we investigated how radiation pattern changes according to three angles ($30^{\circ}$, $90^{\circ}$, $150^{\circ}$) of Top Loading. In this paper, we measured and compared the SNR (Signal-to-Noise Ratio) and BER (Bit Error Rate) performances of the proposed antennas in the condition between an ideal environment of anechoic chamber and smart house existing practical electromagnetic interferences (Universal Software Radio Peripheral, USRP). Throughout the comparing the results of the measurement of two cases, we found that the SNR is degraded over 5dB in average and BER is increased over ten times in maximum, therefore, it is confirmed that the error rate of receiving signal is increased. The measured results of SNR and BER value in this paper able to expect the performance degrading by the interference from the electromagnetic devices.

• Journal of the Korean Institute of Gas
• /
• v.19 no.2
• /
• pp.12-19
• /
• 2015

$CO_2$ is non-flammable, non-toxic gas and not cause of chemical explosion. However, various impurities and some oxides can be included in the captured $CO_2$ inevitably. While the $CO_2$ gas was temporarily stored, the pressure in a storage tank would be reached above 100bar. Therefore, the tank could occur a physical explosion due to the corrosion of vessel or uncertainty. Evaluating the intensity of explosion can be calculated by the TNT equivalent method generally used. To describe the physical explosion, it is assumed that the capacity of a $CO_2$ temporary container is about 100 tons. In this work, physical explosion damage in a $CO_2$ storage tank is estimated by using the Hopkinson's scaling law and the injury effect of human body caused by the explosion is assessed by the probit model.

• Korean Journal of Applied Biomechanics
• /
• v.15 no.3
• /
• pp.161-173
• /
• 2005

Recently among several tennis techniques forehand stroke has been greatly changed in the aspect of spin, grip and stance. The most fundamental factor among the three factors is the stance which consists of open, square and closed stance. The purpose of this study was to investigate the relations between the segments of the body, the three dimensional anatomical angle according to open stance patterns during forehand stroke in tennis. For the movement analysis three dimensional cinematographical method(APAS) was used and for the calculation of the kinematic variables a self developed program was used with the LabVlEW 6.1 graphical programming(Johnson, 1999) program. By using Eular's equations the three dimensional anatomical Cardan angles of the joint and racket head angle were defined 1. In three dimensional maximum linear velocity of racket head the X axis showed $11.41{\pm}5.27m/s$ at impact, not the Y axis(horizontal direction) and the z axis(vertical direction) maximum linear velocity of racket head did not show at impact but after impact this will resulted influence upon hitting ball It could be suggest that Y axis velocity of racket head influence on ball direction and z axis velocity influence on ball spin after impact. the stance distance between right foot and left foot was mean $74.2{\pm}11.2m$. 2. The three dimensional anatomical angular displacement of shoulder joint showed most important role in forehand stroke. and is followed by wrist joints, in addition the movement of elbow joints showed least to the stroke. The three dimensional anatomical angular displacement of racket increased flexion/abduction angle until the impact. after impact, The angular displacement of racket changed motion direction as extension/adduction. 3. The three dimensional anatomical angular displacement of trunk in flexion-extension showed extension all around the forehand stroke. The angular displacement of trunk in adduction-abduction showed abduction at the backswing top and adduction around impact. while there is no significant internal-external rotation 4. The three dimensional anatomical angular displacement of hip joint and knee joint increased extension angle after minimum of knee joint angle in the forehand stroke, The three dimensional anatomical angular displacement of ankle joint showed plantar flexion, internal rotation and eversion in forehand stroke. it could be suggest that the plantar pressure of open stance during forehand stroke would be distributed more largely to the fore foot. and lateral side.

• Korean Journal of Applied Biomechanics
• /
• v.24 no.2
• /
• pp.151-160
• /
• 2014

The purpose of this study was to investigate the GRF(ground reaction force) parameters according to the shoes's heel heights and ground landing distances during downward stairs on bus. Participants selected as subject were consisted of young and healthy women(n=9, mean age: $21.30{\pm}0.48$ yrs, mean height: $164.00{\pm}3.05cm$, mean body mass: $55.04{\pm}4.41kg$, mean BMI: $20.47{\pm}1.76kg/m^2$, mean foot length: $238.00{\pm}5.37mm$). They were divided into 2-types of shoe's heel heights(0 cm/bare foot, 9 cm) and also were divides into downward stairs with 3 types of landing distance(20 cm, 35 cm, 50 cm). A one force-plate was used to collect the GRF(AMTI, USA) data from the sampling rate of 1000 Hz. The GRF parameters analyzed were consisted of the medial-lateral GRF, anterior-posterior GRF, vertical GRF, loading rate, Center of Pressure(${\Delta}COPx$, ${\Delta}COPy$, COP area) and Dynamic Postural Stability Index(MLSI, APSI, VSI, DPSI) during downward stairs on bus. Medial-lateral GRF and vertical GRF didn't show significant differences statistically according to the shoe's heel heights and landing distance, but 9 cm shoes heel showed higher vertical GRF than that of 0 cm bare foot in landing distance of 50 cm. Also anterior-posterior GRF didn't show significant difference statistically according to the shoe's heel heights, but landing distance of 20 cm showed higher than that of landing distances of 35 cm and 50 cm in anterior-posterior GRF. Loading rate didn't show significant difference statistically according to the landing distance, but 9 cm shoe's heel showed higher than that of 0 cm bare foot during downward stairs. The ${\Delta}COPy$ and COP area didn't show significant differences statistically according to the shoe's heel heights and landing distance, but 0 cm bare foot showed higher than that of 9 cm shoe's heel in ${\Delta}COPx$. Dynamic Postural Stability Index(MLSI, APSI, VSI, DPSI) didn't show significant differences statistically according to the landing distance, but 9 cm shoe's heel showed decreased value than that of 0 cm bare foot in dynamics balance. Considering the above, parameters of GRF showed different characteristics according to the shoe's heel heights and ground landing distances during downward stairs on bus.

• Biomolecules & Therapeutics
• /
• v.2 no.4
• /
• pp.369-375
• /
• 1994

A polysaccharide, G009, isolated from Ganoderma lucidum IY 009, was subjected to investigating on general pharmacology. This material at the large oral doses of 1000 and 2000 mg/kg in mice did not exhibit any abnormal behaviors and another effects on central nervous system. It also had no influences on hexobarbital-induced sleeping time, rotarod test and spontaneous activity test at each oral dose of 1000 mg/kg in mice. No effects on the body temperature and on acetic acid induced writhing syndrome in mice were observed with its oral administration at 1000 mg/kg, and the convulsions induced by strychnine and pentetrazole were not inhibited at its oral doses of 1000 mg/kg in mice. The solution of G009 as given intravenously at the doses of 30 and 60 mg/kg in rabbit had no influences on blood pressure and respiration rates and depth. In isolated organs of rat uterus and fundus muscles and guineapig ileum and trachea, it did not show any contraction or relaxation at the concentrations of 2$\times$10$^{-3}$ g/ml, and the contractive actions produced by oxytocin, acetylcholine, serotonin and histamine were not inhibited at the same doses. This material showed no effect on intestinal propulsion test in mice and gastric secretion in rats at the oral doses of 1000 mg/kg. However, it is interesting that the material exhibited potent inhibition of acidified aspirin induced gastric damage at the doses of 500 and 1000 mg/kg in rats.

• Journal of Genetic Medicine
• /
• v.14 no.1
• /
• pp.8-17
• /
• 2017

Purpose: Pulse wave velocity (PWV) is an indicator of arterial stiffness, and is considered a marker of vascular damage. However, a genome-wide association study analyzing single nucleotide polymorphisms (SNPs) associated with brachial-ankle PWV (baPWV) has not been conducted in healthy populations. We performed this study to identify SNPs associated with baPWV in healthy populations in Korea. Materials and Methods: Genomic SNPs data for 2,407 individuals from three sites were analyzed as part of the Korean Genomic Epidemiologic Study. Without replication samples, we performed multivariable analysis as a post hoc analysis to verify the findings in site adjusted analysis. Healthy subjects aged between 40 and 70 years without self-reported history or diagnosis of hypertension, diabetes, hyperlipidemia, heart disease, cerebrovascular disease and cancer were included. We excluded subjects with a creatinine level >1.4 mg/dL (men) and 1.2 mg/dL (women). Results: In the site-adjusted association analysis, significant associations (P<$5{\times}10^{-8}$) with baPWV were detected for only 5 SNPs with low minor allele frequency. In multivariable analysis adjusted by age, sex, height, body mass index, mean arterial pressure, site, smoking, alcohol, and exercise, 11 SNPs were found to be associated (P<$5{\times}10^{-8}$) with baPWV. The 5 SNPs (P<$5{\times}10^{-8}$) linked to three genes (OPCML, PRR35 and RAB40C) were common between site-adjusted analysis and multivariable analysis. However, meta-analysis of the result from three sites for the 11 SNPs showed no significant associations. Conclusion: Using the recent standard for genome-wide association study, we did not find any evidence of significant association signals with baPWV.

• Journal of the Korean Society of Food Culture
• /
• v.11 no.3
• /
• pp.305-316
• /
• 1996

The purpose of this study was to find out how much they have several aspects of food related knowledge and eating behaviors of high school students in Sungnam area. The self-administrated questionnaire was used. The result were as follows: 1. The average height of boys and girls was $172.6{\pm}0.7$ cm and $156.3{\pm}1.5$ cm respectively. The average weights of them were $62.4{\pm}0.5$ kg (male) and $47.2{\pm}0.8$ kg (female). BMI (Body Mass Index) of them were $20.74{\pm}0.14$ (male), $18.82{\pm}0.28$ (female). The average age is 16.7 years old. 2. The 66.5% of the subjects were spent more than one-third of their pocket money in buying on light meals during three times a week. There were significant differences between income level of family. Boys spent more money on each meal than girls. And significant differences were also obserbed by their residence area and Bundang residences spent more in buying snacks. 3. The rate of skipping meals was 51.2% in boys compared with 68.0% in girls. The frequencies of buying snacks instead of main meal were high in girls. Time limits in eating may possibly be the main reason for skipping meals (59.8%), especially in the morning. Skipping a breakfast becomes general eating habits in high school students, because of pressure for time to go to school. 4. It is required that parents should be taught to prepare balanced lunch box for their children because the rate of students who prepared two lunch boxes are 49.4%. 5. The students took snacks once or twice a day. They usually bought snacks in school concessions (51.8%) and they selected items of snack instinctivly. The girls ate snacks during lunch break time (31.7%) and after dinner (23.6%). Boys ate snacks after dinner (29.1%). Preference of foods were different by sex. Boys preferred bread (31.7%), milk and otherdairy products (80.8%), cola and soda (42.0%) as their snacks between meals. Girls selected biscuit, chip, beverage, coffee as their snacks, frequently. 6. BMI value of the group who ate between meals more than three times a day was lower $(18.78{\pm}0.65)$ than that of the group who ate nothing between meals $(20.71{\pm}3.79)$. 7. As for the nutritional knowledge, the students generally had higher correct rate of answer about which nutritive components of food has (76.6%). But they had lower knowledge on questions of nutritive values in food (10.6%). There was a meaningful relation between favorite food and nutritional knowledge. In conclusion, there were some problems on nutritional knowledge and eating habits among the high school students. Therefore, it was required that girls should be learned to recognize the importance of breakfast and needed to select balanced meals and snacks. And it was required that the nutrition education should be complemented to motivate and improve practical eating behaviors.

• Kidney Research and Clinical Practice
• /
• v.37 no.4
• /
• pp.356-365
• /
• 2018

Background: Woman kidney donors face obstetric complication risks after kidney donation, such as gestational hypertension and preeclampsia. Studies on childbirth-related complications among Asian women donors are scarce. Methods: This retrospective cohort study included woman donors aged 45 years or younger at the time of kidney donation in a single tertiary hospital between 1985 and 2014. Pregnancy associated complications were investigated using medical records and telephone questionnaires for 426 pregnancies among 225 donors. Matched non-donor controls were selected by propensity score and the maternal and fetal outcomes were compared with those of donors. Primary outcomes were differences in maternal complications, and secondary outcomes were fetal outcomes in pregnancies of the donor and control groups. Results: A total of 56 cases had post-donation pregnancies. The post-donation pregnancies group was younger at the time of donation and older at the time of delivery than the pre-donation pregnancies group, and there were no differences in primary outcomes between the groups except the proportion receiving cesarean section. Comparison of the complication risk between post-donation pregnancies and non-donor matched controls showed no significant differences in gestational hypertension, preeclampsia, or composite outcomes after propensity score matching including age at delivery, era at pregnancy, systolic blood pressure, body weight, and estimated glomerular filtration ratio (odds ratio, 0.63; 95% confidence interval, 0.19-2.14; P = 0.724). Conclusion: This study revealed that maternal and fetal outcomes between woman kidney donors and non-donor matched controls were comparable. Studies with general population pregnancy controls are warranted to compare pregnancy outcomes for donors.

• Journal of Korean Medicine for Obesity Research
• /
• v.13 no.1
• /
• pp.33-45
• /
• 2013

Objectives: This study was aimed to find out the characteristics of ordinary symptoms between the control and patient groups, diagnosed as overweight or obesity, in Soyang, Taeeum, and Soeum Constitutions and among those 3 groups. Methods: As a prospective cross-sectional study based on medical records, 9213 patients, who visited Kyung Hee University Medical Center from May in 2007 to June in 2010, were included. To diagnose the constitution, Revised Questionnaire for the Sasang Constitution Classification II and examinations by oriental medical doctors who majored in Sasang Constitution Medicine were performed. Based on the World Health Organization criteria for Asian obesity assessment, body mass index (BMI) was classified into 3 groups; more than 25 as obesity, 23 to 25 as overweight, and less than 23 as normal. Ordinary symptoms questionnaire, which consists of 46 questions in 8 categories, were given to the subjects. One-way ANOVA test in continuous variables and chi-square test in categorical variables were carried out to analyze statistical significance. Results and Conclusions: 1) In general characteristics, we could find out the significant differences in age, sex, height, weight, BMI, waist circumference, blood pressure, total cholesterol, triglyceride, low density lipoprotein cholesterol, high density lipoprotein cholesterol, fasting blood sugar, and hemoglobin A1c among the 3 Constitutional groups. 2) Soyang Constitution of overweight and obesity has tendency to have higher appetite, like cool or cold water, defecate more, swear more, dislike heat, and have warmer or hotter extremities in the ordinary symptoms, compared with the control group. 3) Taeeum Constitution of overweight and obesity has tendency to have higher appetite, like cool or cold water, defecate more, swear more, dislike heat, and have warmer or hotter extremities in the ordinary symptoms, compared with the control group. 4) Soeum Constitution of overweight and obesity has tendency to have higher appetite and less fatigue in the ordinary symptoms, compared with the control group. 5) Soeum Constitution showed the slightest increase in appetite, preference about room temperature water, less number of feces, and feeling of chill and warmer extremities in ordinary symptoms, compared with Soyang and Taeeum Constitutions. Taeeum Constitution showed the distinct increase in appetite and sweating in ordinary symptoms, compared with Soyang and Soeum Constitutions.