• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.5 s.96
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• pp.511-517
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• 2005

Many cellular phone volunteer studies have been conducted since such a social issue is raised that the long time usage of cellular phone by teenagers may increase health risk. While there were various adult volunteer studies using GSM cellular phone on heart rate and blood pressure, very few teenager studies using CDMA phone were conducted. In this study, two volunteer groups of 21 teenagers and 21 adults were exposed to 300 mW CDMA wave for half an hour, and the physiological parameters such as blood pressure, heart rate, respiration rate, and skin impedance were investigated. All the parameters fur both groups were unaffected during exposure except the skin impedance of teenager group.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.1
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• pp.49-54
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• 2016

The wind power plants were installed in many places because of the low climate changing effects since 2000. Generally, the wind power plants located in the seaside and the mountainous area and the heights of the windmills are about 40 m~140 m above the ground level. So the noises emitted from the wind power plants propagate far away compared with other environment noise sources like trains and cars noise. Because of these reasons, the noise emitted from the wind power plant is easy to cause the additional social problems like as noise complaints. Under the situation, the ministry of environment has established the guideline to evaluate the environmental effects for the wind power plant. According to the guideline, the noise of the wind power plant has to meet 55 dB(A) at daytime and 45 dB(A) at night in the residential area, which is regulated in the noise and vibration management law. But, it is difficult to estimate the noise emitted from the wind power plant because of the absence of the prediction model of the wind power plant noise. Therefore, the noise prediction model for wind power plants using the regression analysis method is developed in this study. For the development of the model, the sound pressure levels of the wind power plants in Jeju island are measured and the correlations between the sound pressure levels are analyzed. Finally, the prediction equation of the wind power plant noise using by regression analysis method derived. The prediction equation for the wind power plant noise proposed in this study can be useful to evaluate the environmental effects in any wind power plant development district.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.5
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• pp.315-323
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• 2021

Tunnel is the most energy-consuming structure in road due to the characteristic of using artificial lighting during day and night. Therefore, tunnel lights are being replaced by LED lamp that have advantages with respect to low power consumption. The best use of social overhead capital can be expected by considering the life cycle cost, because to tunnel structures are accompanied by a series of medium-to-long-term and continuous processes of replacing auxiliary facilities. In this study, the saving effect by LCC analysis was quantitatively analyzed by replacing tunnel light sources from high-pressure sodium lamps to LED lamps. The effect of reducing the replacement cycle by increasing the life of the lamps and the resulting maintenance cost is very significant, on replacing tunnel lighting light sources with LED lamp.

• Journal of Trauma and Injury
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• v.32 no.3
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• pp.136-142
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• 2019

Purpose: Near drowning refers to immediate survival after asphyxia due to submersion or immersion in water, which is a crucial public safety problem worldwide. Acute lung injury or acute respiratory distress syndrome (ARDS) is a common complication of near drowning. The purpose of this study was to investigate the feasibility and effectiveness of noninvasive nasal positive pressure ventilation (NINPPV). Methods: This retrospective study was conducted at a tertiary emergency department. NINPPV was administered for moderate ARDS caused by submersion or immersion in patients who were older than 18 years, from January 2015 to December 2018. We collected the demographic (age, sex, length of hospital stay, and outcome), laboratory (arterial blood gas, lactate, oxygen saturation, partial pressure of oxygen divided by the fraction of inspired oxygen, complete blood count, blood urea nitrogen, and creatinine), and clinical data (acute lung injury index and ventilator failure) of the patients. A statistical analysis was performed using Statistical Package for the Social Sciences version 20.0 for Windows. Results: NINPPV treatment was provided to 57 patients for near drowning, 45 of whom (78.9%) were successfully treated without complications; in 12 (21.1%), treatment was changed to invasive mechanical ventilation within 48 hours due to ARDS or acute kidney injury. NINPPV treatment was successful in 31 (75.6%) out of 41 sea-water near drowning patients. They were more difficult to treat with NINPPV compared with the fresh-water near drowning patients (p<0.05). Conclusions: NINPPV would be useful and feasible as the initial treatment of moderate ARDS caused by near drowning.

• Physical Therapy Rehabilitation Science
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• v.7 no.4
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• pp.164-171
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• 2018

Objective: The purpose of this research was to determine the immediate effects of wearing a foot-pressure-based insole (FPBI) on ankle dorsiflexion range of motion (DFROM), postural sway, and muscle activation in healthy individuals with genu varum. Design: Cross-sectional study. Methods: This study was conducted on thirteen adults, with six male and seven females subjects. The mean age was 24.08 years. Foot pressure was measured to apply the FPBI and the weight bearing lunge test was performed with the application of a flat insole (FI) and FPBI. Examination was randomly performed in four conditions to measure both postural sway and muscle activation. All participants applied both the FI and FPBI with four conditions. The four conditions were as follows: 1) Romberg test posture with eyes closed, 2) Romberg test posture with eyes opened, 3) dominant single leg standing with eyes opened, and 4) non-dominant single leg standing with eyes opened. Results: For ankle DFROM between the FI and FPBI, a significant increase was observed in both the dominant and non-dominant leg (p<0.05). For postural sway between the FI and FPBI in the Romberg test posture with eyes closed and dominant single leg standing with eyes opened conditions, a significant decrease was observed (p<0.05). However, the postural sway between FI and FPBI in the Romberg test posture with eyes opened and non-dominant single leg standing with eyes opened, no significant decrease was observed. Also, there were no significant effects on muscle activation between the application of the FI and FPBI. Conclusions: The result showed that FPBI immediately improved ankle DFROM and postural sway. It seems that FPBI may improve genu varum in healthy individuals with genu varum.

• Journal of agricultural medicine and community health
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• v.23 no.2
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• pp.229-242
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• 1998

Face-to-face interviews were carried out to investigate the relationship between social networks and hypertension in 958 rural residents(males=440, females=518) aged 60-64 of a community-dwelling sample of Dalsung County from April to September in 1996. Eight elements of social network were measured : marital status, regular religious attendance, membership in groups, number of friends, relatives, siblings, children, grandchildren. Hypertensives were defined as meeting at least one of following criteria : hypertension history, systolic blood pressure more than 160 mmHg, diastolic blood pressure more than 95 mmHg. In univariate logistic regression for males, having 1-4 friends vs. none showed odds ratio 0.43 (95% Confidence interval CI 0.19-0.96) and having 2-3, 4 and more than 5 children had reduced prevalence of hypertension with odds ratios 0.21 (95% CI 0.06-0.72), 0.14 (95% CI 0.04-0.49), 0.24 (95% CI 0.07-0.82), respectively when compared with persons without children. In females, there was no elements of social network statistically significant. Having 5-9 grandchildren vs. none showed a marginally significant odds ratio 0.42. In multivariate logistic regression models for males with adjustment for age, education, body mass index, smoking and drinking, number of friends and children showed increased odds ratios and number of close relatives gained a statistically significant odds ratios (0.44-0.50). In females, the adjustment yielded little changes of odds ratios except number of grandchildren which gained a statistically significance. These results suggest that only a certain elements of social network may be associated with reduced risk of hypertension and they may be different between genders in rural resident aged 60-64.

• Korean Journal of Community Nutrition
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• v.20 no.6
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• pp.433-446
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• 2015

Objectives: This study was performed to evaluate the consumer education program for reducing sodium intake based on social cognitive theory (SCT) and investigate consumer perceptions of environmental, cognitive and behavioral factors. Methods: Consumers (n=4,439) were recruited nationwide in Korea to participate in a nutrition education program for reducing sodium intake which was targeted on senior housewives (SH), parents (P), and office workers (OW). Questions regarding main factors of SCT were asked both before and after the education program. Results: SH and P recognized external social efforts and information to reduce sodium including nutrition labeling more than OW. The main barriers to practice reducing sodium intake were limited choice of low sodium food and menu, interference with social relationship when dining with others, and limited information, knowledge and skills. SH had lower barriers to practice reducing sodium intake and OW perceived 'preference to soup or stew' and 'preference to Kimchi, salted fish and fermented sauces' as barriers more than other groups at the baseline. Less than 50% of participants knew the relationship between sodium and salt, sodium in nutrition labeling, and recommended sodium intake. In addition, OW had little knowledge for capability to reduce sodium intake and lower self-efficacy to practice compared with SH and P. After education, positive outcome expectations such as lowering blood pressure, prevention of cardiovascular disease and osteoporosis were increased and barriers to practice reducing sodium intake were decreased in all groups (p < 0.05). The knowledge for behavioral capability and self-efficacy to reduce sodium intake were also improved but OW had still lower scores compared with other groups. Conclusions: These results suggested that nutrition education programs could be an effective tool to impact general population by facilitating awareness and increased capability to reduce sodium intake.

• Korean Journal of Culture and Social Issue
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• v.10 no.spc
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• pp.87-115
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• 2004

This paper examines the influence of interpersonal relationship on delinquent behavior among adolescents. The role that parent-child relationship, teacher-student relationship, and relationship with friends play on delinquent behavior is reviewed. Review of empirical studies reveal the following results. First, adolescents who perceive their parents as being hostile and rejecting are more likely to engage in delinquent behavior. Second, those adolescents with parents, who have low expectations and who are less likely pressure them to succeed academically, are more likely to engage in delinquent behavior. Third, adolescents who feel that they have been abandoned by their parents are more likely to engage in delinquent behavior. Fourth, those adolescents with low social support from parents and teachers and high social support from their friends are more likely to engage in delinquent behavior. Fifth, those students who feel hostility from their teachers, have negative relationship with teachers, and experience greater punishment are more likely to engage in delinquent behavior. The results indicate that punishment can have adverse effect on some adolescents, further damaging the teacher-student relationship. Punishment can further reinforce the existing negative cycle that can increase the likelihood of adolescents engaging in delinquent behavior. The results indicate that a lack of support from parents and teacher leads to low academic and self-regulatory efficacy, which leads to low academic performance, which can results in punishments that could further damage their relationship with their parents and teachers and bring them closer to their friends. Adolescents caught up in this negative cycle are more likely to engage in delinquent behavior. These results indicate the need to reform the relational, social, and cultural environment of adolescents who are engaged in delinquent behavior.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.1
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• pp.63-77
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• 2015

Tsunami take away life, wash houses away and bring devastation to social infrastructures such as breakwaters, bridges and ports. The coastal structure targeted object in this study can be damaged mainly by the wave pressure together with foundation ground failure due to scouring and liquefaction. The increase of excess pore water pressure composed of oscillatory and residual components may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, the bore was generated using the water level difference, its propagation and interaction with a vertical revetment analyzed by applying 2D-NIT(Two-Dimensional Numerical Irregular wave Tank) model, and the dynamic wave pressure acting on the seabed and the surface boundary of the vertical revetment estimated by this model. Simulation results were used as input data in a finite element computer program(FLIP) for elasto-plastic seabed response. The time and spatial variations in excess pore water pressure ratio, effective stress path, seabed deformation, structure displacement and liquefaction potential in the seabed were estimated. From the results of the analysis, the stability of the vertical revetment was evaluated.

• Journal of Korean Society of Transportation
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• v.25 no.3
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• pp.45-54
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• 2007

Aggressive driving is defined as 'driving behavior which intentionally incurs danger and distress to other drivers and passengers'. It increases the possibility of traffic accidents. Also, it threatens lives of drivers ana passengers and brings social and economic harm. According to previous studies. these aggressive behaviors are affected by not only the personality of drivers but also psychosocial factors, such as attitude, aggressive intention, time pressure, and traffic situations, However, most studies on aggressive behaviors conducted with field studies and surveys suggest correlation, not causal relationship. Therefore, in the current study tue authors measured individual factors-the driver's intention for aggressive driving and manipulated time pressure-to examine the interaction effects. As a result. the difference between conditions was significant depending on the level of aggressive intention and time pressure. These differences were also significant depending on the types of aggressive driving behaviors. In particular, the interaction effect of the driver's intention and time pressure on improper passing (cutting drivers off when passing) was significant. Finally the limitations of the current study and implications or using a car simulator are discussed.