• Korean Journal of Applied Biomechanics
• /
• v.23 no.3
• /
• pp.201-208
• /
• 2013

The aim of this study was to investigate badminton smash and drop motion depends on player's level. To perform this study, ten male badminton players were participated: five skilled players (SG, age: $21.6{\pm}1.1$ yrs, height: $181.4{\pm}6.8$ cm, body mass: $72.4{\pm}5.7$ kg, career: $11.2{\pm}1.1$ yrs) and five less-skilled players (LSG, age: $21.2{\pm}1.1$ yrs, height: $180.2{\pm}5.6$ cm, body mass: $73.6{\pm}6.7$ kg, career: $10.6{\pm}0.9$ yrs). Three-dimensional motion analysis with 7 infrared cameras was performed with a sampling frequency as 200 Hz. Player's swing motion was divided into four events: starting motion (E1), backswing (E2), impact (E3), following (E4). For all upper joints, LSG showed greater angle differences between drop and smash motions than that of SG at E3 (p<.05). For all upper joints, greater angular velocities were found in SG than that of LSG. For both groups, significantly smaller angular velocities were found in drop motion than that of smash motion (p<.05). The greater sequential angular velocities (proximal to distal) were found in SG than LSG during smash motion. Based on our findings, performing the same motion between drop and smash would be related to enhance performance at badminton competition. It is expected that these results will be useful in developing a training program for enhancing performance of badminton athletes.

• Advances in Computational Design
• /
• v.5 no.1
• /
• pp.1-11
• /
• 2020

Soil is the fundamental element in the construction process. Soil problems affect the safety of the structures, even so the high quality of the structures and so, bad soil found the structures will affect the lifetime or even destroy the structures built on it. Therefore, the study of soil is an important step in the construction process and the investigation of the most effective characteristics of a special kind of soil (shale soil), i.e. Atterberg limits, swelling pressure, swelling potential and unconfined compression strength, are the most effective soil properties. A big projects will be constructed in new urban extension areas with expansive shale soils, like at Al-Kawamil and new Akhmim shale soils which associated with soil problems, treatment system should be used to ensure the stability of the soil under the structures foundations one of the most effective methods is by adding lime solution to the soil by specific quantities, which affect on the properties of the shale soil by decreasing the swelling and increasing the compressive strength of the treatment soils. Experimenting with the soil added to the lime, it was found that the addition of lime solution 6% improve c j the properties of the soil. The results of the tests showed the high effectiveness of using lime in the treatment of Al-Kawamil soil

• The Journal of Korean Society for School & Community Health Education
• /
• v.18 no.2
• /
• pp.55-70
• /
• 2017

Objectives: The purpose of this study was to identify the factors associated with stage of change for drinking cessation among adolescents on the basis of the Transtheoretical Model. Methods: The data was collected from 343 high school students in Kimhae-city, who have experienced any kind of alcohol in their lifetime. For data analysis, descriptive statistics and Logistic regression were performed using the SPSS WIN 18. 0 program. Results: The stage of change was as follows: 24.2% in the precontemplation stage, 8.7% in the contemplation stage, 10.8% in the preparation stage, 39.7% in the action stage and 16.6% in maintenance stage. The predictive factors to move from the precontemplation stage to the contemplation/preparation stage were dramatic relief (OR=1.36, 95% CI:1.13-1.63) and self-efficacy (OR=1.05, 95% CI:1.01-1.09). The predictive factors to move from the contemplation/preparation stage to the action/maintenance stage were female (OR=0.50, 95% CI:0.27-0.94), the number of friend who have drunk (OR=0.84, 95% CI:0.77-0.91) and self-efficacy (OR=1.04, 95% CI: 1.00-1.07). Conclusions: To stop adolescent drinking, this study suggests the intervention program needs to be considered the individual's stage of change of drinking. The intervention program to enhance dramatic relief and self-efficacy is needed to adolescents in the precontemplation stage. It is crucial to develop strategies to raise self-efficacy for adolescents in the contemplation/preparation stage, which also respect their gender and peer groups.

• Analyses & Alternatives
• /
• v.6 no.1
• /
• pp.35-68
• /
• 2022

In this paper we define wage premium of college hierarchy as a wage differential among college graduates from different universities within the same graduate cohort and estimate the wage premium of college hierarchy for the three different cohorts: namely, 1982, 1992, and 2002. We utilize a unique data set called Education-Labor Market Lifetime Path Survey, which contains education and labor market information about the three different college graduate cohorts. We find that the wage premium of college hierarchy changes over time for the same cohort. It tends to large right after graduation but decrease with labor market experience. When the test score at the time of college entrance controlled, the wage premium of college hierarchy mostly disappears for the 1992 cohort. But for the 2002 cohort it remains seven years after graduation. The difference in the wage premium of college hierarchy can be explained, at least partly, by the number of colleges, college enrollment ratio, and the relation between college hierarchy and the entrance test score.

• The World Journal of Men's Health
• /
• v.39 no.2
• /
• pp.366-375
• /
• 2021

Purpose This study aimed to understand the characteristics of sexual behaviors among Korean adults to facilitate the development of strategies and policies focused on sexual health in groups categorized by sociodemographic characteristics. Materials and Methods A nationally representative probability sample of 2,500 individuals (1,273 men and 1,227 women) aged 18-69 years obtained using a stratified multiple-stage sampling method based on Statistics Korea (KOSTAT) participated in a cross-sectional online survey. The survey consisted of structured questionnaires comprising questions on demographic information, lifetime sexual behavior, and sexual behavior in the previous 12 months. The mean age at first sexual intercourse was lower in men than in women (21.9±4.4 vs. 24.1±4.4 years, p=0.001). The overall prevalence rate of sexual events with casual partners within previous 12 months was 13.1% (95% confidence interval [CI], 11.6%-14.5%). It was found to more commonly exist among lower age groups and men. The overall regular condom use rates with relationship partner and casual partner were 14.8% (95% CI, 13.2%-16.4%) and 39.6% (95% CI, 33.9%-45.3%), respectively. Condom use rate with casual partners among 20s and 30s men was 51.2%. Overall, only 10.4% of the respondents had received sexual education about sexually transmitted infections. This study provided contemporary sexual behaviors in Korean adults, and identified socio-demographic factors that seem to influence sexual behaviors. Low condom use rates and low rate of receiving sexual education were concerns. The result of this study would be useful to health professionals to formulate policies and strategies related to sexual health.

• Korean Journal of Applied Biomechanics
• /
• v.26 no.2
• /
• pp.167-174
• /
• 2016

Objective: The purpose of this study was to determine the interrelationship between ranges of motion of the knee and ankle joints on the sagittal plane and the attenuation magnitude of impact shock at high frequency (9~20 Hz) in the support phase during downhill running. Method: Fifteen male heel-toe runners with no history of lower extremity injuries were recruited for this study (age, $25.07{\pm}5.35years$; height, $175.4{\pm}4.6cm$; mass, $75.8{\pm}.70kg$). Two uniaxial accelerometers were mounted to the tuberosity of tibia and sacrum, respectively, to measure acceleration signals. The participants were asked to run at their preferred running speed on a treadmill set at $0^{\circ}$, $7^{\circ}$, and $15^{\circ}$ downhill. Six optical cameras were placed around the treadmill to capture the coordinates of the joints of the lower extremities. The power spectrum densities of the two acceleration signals were analyzed and used in the transfer function describing the gain and attenuation of impact shock between the tibia and the sacrum. Angles of the knee and ankle joints on the sagittal plane and their angle ranges were calculated. The Pearson correlation coefficient was used to test the relationship between two variables, the magnitude of impact shock, and the range of joint angle under three downhill conditions. The alpha level was set at .05. Results: Close correlations were observed between the knee joint range of motion and the attenuation magnitude of impact shock regardless of running slopes (p<.05), and positive correlations were found between the ranges of motion of the knee and ankle joints and the attenuation magnitude of impact shock in $15^{\circ}$ downhill running (p<.05). Conclusion: In conclusion, increased knee flexion might be required to attenuate impact shock during downhill and level running through change in stride or cadence while maintaining stability, and strong and flexible ankle joints are also needed in steeper downhill running.

• Journal of the Mineralogical Society of Korea
• /
• v.24 no.1
• /
• pp.43-53
• /
• 2011

Health risk assessments for the abandoned asbestos mine were usually performed with activity-based sampling (ABS) method, which was not a effective tool for indexing health risk on an exact small area of mine. A newly proposed potential index of health risk (PIHR) was applied with proper spatial determination of geographical information system (GIS) to assess quantitatively health risks. A new trial was applied to a certain abandoned mine in Boryong as follows: A high grade area of PIHR was estimated 7.8% of the whole area of the mine (about 27.3 ha). Based on US EPA IRIS (integrated risk information system) model considering lifetime excess cancer risk (LECR), the health risk assessment indicated that the high grade area increased from 3.0 ha through 12.9 ha to 19.5 ha with an increase of asbestos contents in soil from 0.36% (1E-04 level) through 0.1% (3E-05 level) to 0.04% (1E-05 level). These results can be effectively applied to determine reclamation area of the abandoned asbestos mine.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.15
• /
• pp.6697-6704
• /
• 2015

Background: The burden of breast and cervical cancer is changing over time in developing countries. Regular screening is very important for early detection and treatment. In this study, we assessed inequalities in breast and cervical cancer screening rates in women according to household wealth status, and analyzed the potential predictors associated with a low cancer screening rate in Jordan. Materials and Methods: A nationwide populationbased cross-sectional survey collected information on different variables at the national level. All ever-married women (the phrase is used throughout the text to refer to women who had ever married) aged 15-49 years were included in the survey. Analysis of breast self-examination (BSE) and clinical breast examination (CBE) at least once in the previous year was carried out in 11,068 women, while lifetime Pap-smear testing was carried out in 8,333 women, aged 20-49 years. Results: Over 39% and 19% of ever-married Jordanian women reported having undergone a breast examination during the previous year and Pap smear examination at least once in their lifetime, respectively. The rate of BSE in the previous year was 31.5%, that of CBE in the previous year was 19.3%, and that of Pap smear examination at least once in life was 25.5%. The adjusted OR was higher for performing BSE (aOR 1.22, 95% CI 1.04-1.43), undergoing CBE (aOR 1.31, 95% CI 1.08-1.60) and undergoing Pap smear examination (aOR 2.38, 95% CI 1.92-2.93) among women in the highest wealth-index quintile as compared to those in the lowest quintile. The concentration index was 0.11 for BSE, 0.01 for CBE, and 0.27 for Pap smear examination. Women in their twenties, living in rural or the southern region of Jordan, with an elementary school education or less, who listened to the radio or read the newspaper not more than a few times a year, and nulliparous women were less likely to undergo breast and cervical cancer screening. Conclusions: The rates of breast and cervical cancer screening are low in Jordan. Reducing the sociodemographic and economic inequalities in breast and cervical cancer screenings requires concerted outreach activities for women living under socially deprived conditions.

• Journal of Family Resource Management and Policy Review
• /
• v.26 no.4
• /
• pp.39-52
• /
• 2022

The purpose of this study was to examine the workday leisure time of dual-income fathers and mothers with preschool children. Data were gathered from the Statistics Korea Life Time Surveys from 2004(y1) and 2019(y2) (n=2,697). Life time was composed of three types(inevitable time, compulsory time, and leisure time) and leisure time was categorized into 11 activities(voluntarism, participation, social relationships, religion, rituals, culture and tourism, sports, game and play, media, rest, and others) to investigate gender differences and time effects. The major results were as follows: First, both working fathers and mothers with preschool children spent less inevitable time, more compulsory time, and less leisure time, than other adult group. Second, fathers spent more time on 10 leisure activities except religion in y1, and on all activities than mothers in y2. In y2, less time on three activities(social relationships, rituals, and media) for both fathers and mothers, less time on religion for mothers only, more time on two activities(participation, game and play) for both groups were spent than y1. Third, in the regression analysis of fathers' and mothers' leisure time on three leisure activities(sports, game and play, and media) with a distinct pattern from leisure time for adult group between y1 and y2, socioeconomic variables and lifetime variables showed different effects by gender and waves. Based on the results, family policy and programs to improve the work-life balances of working fathers and mothers discussed.

• Journal of Environmental Health Sciences
• /
• v.46 no.5
• /
• pp.576-587
• /
• 2020

Objectives: This study calculated local residents exposures to VOCs (Volatile Organic Compounds) released into the atmosphere using the CalTOX model and carried out uncertainty analysis and sensitivity analysis. The model validity was analyzed by comparing the predicted and the actual atmospheric concentrations. Methods: Uncertainty was parsed by conducting a Monte Carlo simulation. Sensitivity was dissected with the regression (coefficients) method. The model validity was analyzed by applying r² (coefficient of determination), RMSE (root mean square error), and the Nash-Sutcliffe EI (efficiency index) formula. Results: Among the concentrations in the atmosphere in this study, benzene was the highest and the lifetime average daily dose of benzene and the average daily dose of xylene were high. In terms of the sensitivity analysis outcome, the source term to air, exposure time, indoors resting (ETri), exposure time, outdoors at home (ETao), yearly average wind speed (v_w), contaminated area in ㎡ (Area), active breathing rate (BRa), resting breathing rate (BRr), exposure time, and active indoors (ETai) were elicited as input variables having great influence upon this model. In consequence of inspecting the validity of the model, r² appeared to be a value close to 1 and RMSE appeared to be a value close to 0, but EI indicated unacceptable model efficiency. To supplement this value, the regression formula was derived for benzene with y=0.002+15.48x, ethylbenzene with y ≡ 0.001+57.240x, styrene with y=0.000+42.249x, toluene with y=0.004+91.588x, and xylene with y=0.000+0.007x. Conclusions: In consequence of inspecting the validity of the model, r² appeared to be a value close to 1 and RMSE appeared to be a value close to 0, but EI indicated unacceptable model efficiency. This will be able to be used as base data for securing the accuracy and reliability of the model.