• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.489-495
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• 2016

In this study, the Warm-Mix Asphalt was prepared using a modified Sulfur Binder mixed with an additive of a polymer component in sulfur, which is an industrial by-product generated in the crude oil refining process. The dynamic stability and durability characteristics of the prepared Warm-Mix Asphalt was evaluated by the indirect tensile strength, the tensile strength ratio before and after water immersion and freezing-thawing, and the dynamic stability by wheel tracking test. The Warm-Mix Asphalt Mixtures using Modified Sulfur Binder has a tensile strength ratio before and after water immersion of 0.88, which is about 1.13 times that of the Warm-Mix formed modified Asphalt, and the tensile strength ration before and after freezing-thawing is also 0.82, thus, all tensile strength ratios satisfied the KS quality standard value of 0.75 or more. The indirect tensile strength was 1.6MPa which was twice the KS quality standard value of 0.8MPa, and about 1.24 times higher than that of normal heated asphalt 1.29MPa. In addition, the dynamic stability by the wheel tracking test was 14,075 times/mm, which was about 15 times higher than that of normal heated asphalt and about 3 times higher than that of the Warm-Mix formed modified Asphalt, showing excellent resistance to plastic deformation such as fatigue cracks.

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

• The Journal of Korean Institute of Information Technology
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• v.16 no.11
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• pp.51-59
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• 2018

The Multi-Mission Unmanned Surface Vehicle(MMUSV), which is manufactured using glass Fiber Reinforced Plastic(FRP) material, is designed to perform a surveillance and reconnaissance on the sea. Various navigation sensors, such as RADAR, RIDAR, camera, are mounted on a mast to perform an autonomous navigation. And a dummy gun is mounted on the deck of the MMUSV for a target tracking and disposal. It is necessary to analyze a strength for structures mounted on the deck because the MMUSV performs missions under a severe sea state. In this paper, a strength analysis of the mast structure is performed on static loads and lateral external loads to verify an adequacy of the designed mast through a series of simulations. Based on the results of captive model tests, a strength analysis for a heave motion of the mast structure is conducted using a simulation tool. Also a simulation and fatigue test for a mounting part between the MMUSV and the dummy gun are performed using a specimen. The simulation and test results are represented that a structure of the mast and mounting part of the dummy gun are appropriately designed.he impact amount are performed through simulation and experiments.

• Journal of the Korean Applied Science and Technology
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• v.39 no.1
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• pp.115-131
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• 2022

The purpose of this study was to develop and examine the effect of the Health Promotion Education Program for the Auxiliary Police based on the PRECEDE-PROCEED Model. This study was conducted using a nonequivalent control group pretest-posttest design. Twenty-five participants were selected by convenience sampling method and assigned to the experimental group, and 26 participants were assigned to the control group. The data were collected from Auxiliary Police officer in D provincial Police Agency. All of participations completed questionnaires about self-efficacy, social support, availability of resources, health promotion behavior, quality of life and received the objective stress test. In addition, the experimental group completed 7 sessions of health promotion Education programs according to PRECEDE-PROCEED model for 5 weeks. Data were analyzed using the SPSS/WIN 21.0 Program. There was significant differences over time between the groups in terms of health promotion behavior (F=7.63, p<.001), autonomic nervous activity (F=29.24, p<.001), stress resistance (F=31.22, p<.001), stress index (F=22.42, p<.001), fatigue (F=12.87, p<.001), and quality of life (F=3.49, p=.042). The results may be crucial to develop strategy in order to decrease the disease prevalence as well as increase the participants' overall quality of life. As a result, the Health Promotion Education Program for the auxiliary police was proved to be an effective intervention in order to improve the quality of life. Therefore, the program may be a useful intervention for the auxiliary police.

• Journal of Korean Neurosurgical Society
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• v.65 no.6
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• pp.779-789
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• 2022

Objective : To analyze the effects of the number and shape of fenestrations on the mechanical strength of pedicle screws and the effects of bone cement augmentation (BCA) on the pull-out strength (POS) of screws used in conventional BCA. Methods : For the control group, a conventional screw was defined as C1, a screw with cannulated end-holes was defined as C2, a C2 screw with six pinholes was defined as C3, and the control group type was set. Among the experimental screws, T1 was designed using symmetrically placed thru-hole type fenestrations with an elliptical shape, while T2 was designed with half-moon (HM)-shaped asymmetrical fenestrations. T3 and T4 were designed with single HM-shaped fenestrations covering three pitches and five pitches, respectively. T5 and T6 were designed with 0.6-mm and 1-mm wider fenestrations than T3. BCA was performed by injecting 3 mL of commercial bone cement in the screw, and mechanical strength and POS tests were performed according to ASTM F1717 and ASTM F543 standards. Synthetic bone (model #1522-505) made of polyurethane foam was used as a model of osteoporotic bone, and radiographic examinations were performed using computed tomography and fluoroscopy. Results : In the fatigue test, at 75% ultimate load, fractures occurred 7781 and 9189 times; at 50%, they occurred 36122 and 82067 times; and at 25%, no fractures occurred. The mean ultimate load for each screw type was 219.1±52.39 N for T1, 234.74±15.9 N for T2, 220.70±59.23 N for T3, 216.45±32.4 N for T4, 181.55±54.78 N for T5, and 216.47±29.25 N for T6. In comparison with C1, T1, T2, T3, T4, and T6 showed significantly different ultimate load values (p<0.05). However, when the values for C2 and the fenestrated screws were evaluated with an unpaired t test, the ultimate load value of C2 significantly differed only from that of T2 (p=0.025). The ultimate load value of C3 differed significantly from those of T1 and T2 (C3 vs. T1 : p=0.048; C3 vs. T2 : p<0.001). Linear correlation analysis revealed a significant correlation between the fenestration area and the volume of bone cement (Pearson's correlation coefficient r=0.288, p=0.036). The bone cement volume and ultimate load significantly correlated with each other in linear correlation analysis (r=0.403, p=0.003). Conclusion : Fenestration yielded a superior ultimate load in comparison with standard BCA using a conventional screw. In T2 screws with asymmetrical two-way fenestrations showed the maximal increase in ultimate load. The fenestrated screws can be expected to show a stable position for the formation of the cement mass.

• Journal of Korean Academy of Nursing
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• v.53 no.3
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• pp.295-308
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• 2023

Purpose: This study evaluated the validity and reliability of Shively and colleagues' self-efficacy for HIV disease management skills (HIV-SE) among Korean participants. Methods: The original HIV-SE questionnaire, comprising 34 items, was translated into Korean using a translation and back-translation process. To enhance clarity and eliminate redundancy, the author and expert committee engaged in multiple discussions and integrated two items with similar meanings into a single item. Further, four HIV nurse experts tested content validity. Survey data were collected from 227 individuals diagnosed with HIV from five Korean hospitals. Construct validity was verified through confirmatory factor analysis. Criterion validity was evaluated using Pearson's correlation coefficients with the new general self-efficacy scale. Internal consistency reliability and test-retest were examined for reliability. Results: The Korean version of HIV-SE (K-HIV-SE) comprises 33 items across six domains: "managing depression/mood," "managing medications," "managing symptoms," "communicating with a healthcare provider," "getting support/help," and "managing fatigue." The fitness of the modified model was acceptable (minimum value of the discrepancy function/degree of freedom = 2.49, root mean square error of approximation = .08, goodness-of-fit index = .76, adjusted goodness-of-fit index = .71, Tucker-Lewis index = .84, and comparative fit index = .86). The internal consistency reliability (Cronbach's α = .91) and test-retest reliability (intraclass correlation coefficient = .73) were good. The criterion validity of the K-HIV-SE was .59 (p < .001). Conclusion: This study suggests that the K-HIV-SE is useful for efficiently assessing self-efficacy for HIV disease management.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.519-529
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• 2009

Fiber reinforced composite materials have various advantages in mechanical and chemical aspects. Not only high fatigue and chemical resistance, but also high specific strength and stiffness are attained, and therefore, damping characteristics are beneficial to marine piles. Since piles used for marine structures are subjected to compression and bending as well, detailed research is necessary. Current study examine the mechanical behavior under flexural and/or compressive loads using concrete filled fiber reinforced plastic composite piles, which include large size diameter. 25 pile specimens which have various size of diameters and lengths were fabricated using hand lay-up or filament winding method to see the effect of fabrication method. The inner diameters of test specimens ranged from 165 mm to 600 mm, and the lengths of test specimens ranged from 1,350 mm to 8,000 mm. The strengths of the fill-in concrete were 27 and 40 MPa. Fiber volumes used in circumferential and axial directions are varied in order to see the difference. For some tubes, spiral inner grooves were fabricated to reduce shear deformation between concrete and tube. It was observed that the piles made using filament winding method showed higher flexural stiffness than those made using hand lay-up. The flexural stiffness of piles decreases from the early loading stage, and this phenomenon does not disappear even when the inner spiral grooves were introduced. It means that the relative shear deformation between the concrete and tube wasn't able to be removed.

• Journal of Korean Dental Hygiene Science
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• v.7 no.1
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• pp.39-52
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• 2024

Background: Dental hygienists provide direct dental care in the closest proximity to the patient, and each practice requires a high level of focus and concentration. These skills are an important human resource that can impact the quality of dental care services. Since more than half of dental clinics provide as overtime work in addition to regular hours, this study aims to determine the association between working overtime and job performance for dental hygienists. Methods: The study was conducted using a combination of online and in-person surveys via Google Forms among 131 employed dental hygienists. The survey consisted of 7 questions on demographic and work characteristics, 16 questions on characteristics related to overtime and the effect of overtime on job security, health, and life, and 10 questions on job performance, for a total of 33 questions. Chi-square analysis and independent samples t-test were used to identify the characteristics of demographic and work characteristics, and descriptive statistics analysis was used for the characteristics of overtime. Independent samples t-test was used to test the difference in the mean of job performance according to whether or not they worked overtime, and linear regression analysis was used to show the association of working overtime and job performance. Results: The study found that 71% of dental clinics worked overtime. The average number of overtime per week was once (78.5%), and the most common problems with overtime were fatigue (52.7%) and lack of personal and leisure time (41.9%). The appropriate number of overtime per week considered by dental hygienists was once a week, which was confirmed to be 94.6%. When comparing job performance by overtime status, those who worked overtime were 3.38 points higher than those who did not (35.45 vs. 32.07). Multiple linear regression analysis of the association of working overtime night and job performance showed that a one-unit increase in worked overtime was associated with a statistically significant increase in job performance of about 3.1 (p<0.01). Conclusion: Working overtime was found to have a positive effect on job performance among dental hygienists. Therefore, as a way to improve the working environment, providing appropriate compensation or welfare for overtime can reduce the negative aspects of overtime and turn it into a positive influence on job performance. This could ultimately raise awareness of the dental hygienist as a professional and effect the efficiency of dental care services.

• Clinics in Shoulder and Elbow
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• v.15 no.2
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• pp.79-85
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• 2012

Objective: It has been expected that patient with posttraumatic recurrent anterior shoulder dislocation might have limited daily life activity because of pain and apprehension of dislocation. But there have been only a small number of investigations regarding the rotator strength in this patient. The aim of this study is to find the characteristics about rotator strength of patient with posttraumatic recurrent anterior shoulder dislocation using an isokinetic testing. Method: We enrolled thirteen patients with posttraumatic recurrent anterior shoulder dislocation and fifteen sex, age-matched healthy nonathletic subjects in this controlled study. All participants were male and there were no significant differences between the two groups in age, height, weight, BMI. Isokinetic internal rotator and external rotator strength was evaluated with a Biodex Isokinetic Testing machine (Biodex Medical Systems, Shirley, NY, USA), tests were performed at 60 deg/sec and 180 deg/sec for both sides. Peak torque normalized to body weight, external rotator to internal rotator ratio, total work and fatigue were calculated for each angular velocity. The association between internal rotator and external rotator strength and shoulder instability was analyzed by comparisons with a control group. Results: Any notable differences could not be found between the two groups given all data from no symptomatic left shoulder. There were no significant differences between the two groups statistically in internal rotation strength of right shoulder. However, there has been a tendency that at all angular velocities, external rotator peak torque to body weight, total work and external rotator to internal rotator ratio were significantly lower in the anterior instability group than the control group at all angular velocities. There was no substantial difference between those groups with respect to the fatigue of external rotator and internal rotator in our study. Conclusion: The prominent characteristics of posttraumatic recurrent anterior shoulder dislocation are external rotator weakness and loss of balance with external rotator and internal rotator. Therefore selective training using this information rotator might be helpful in conservative treatment and rehabilitation.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.1
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• pp.105-116
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• 2010

Purpose: To analyze and compare differences between single vision lenses and functional progressive addition lenses and improvement to binocular visual function wearing functional lenses for pre-presbyopes altered their single vision lenses to functional progressive addition lenses with low addition. Methods: Healthy 32 subjects aged 24.03${\pm}$1.87 (male 23, female 9) who were recruited from university students wore functional progressive addition lenses (EYE-T, Chemilens Co., Korea, ADD 0.750) for 2 months. Objective refraction, corrected visual acuity at distance and near, near point of convergence, near point of accommodation, accommodative facility, phoria at distance and near were measured. And subjective satisfaction was investigated by using a questionnaire designed to fatigue, comfort, discomfort, overall satisfaction and preference. Results: Functional progressive addition lenses were better than single vision lenses at near point of convergence and accommodation, accommodative facility. Exo phoria measured at distance with single vision and functional progressive addition lenses. Exo phoria measured at near with functional progressive addition lenses was higher than that with single vision lenses. As a survey, the satisfaction was increased in questions related near work. However, single vision lenses were preferred in distance test of overall satisfaction, easy 10 adapt, lime to adapt. A survey showed thai preference of functional progressive addition lenses were increased 75.00% to 81.26% for near work, 50.00% to 65.63% for visual fatigue, 47.75% to 50.00% for visual comfort and 31.25% to 46.88% for overall comfort. Conclusions: Comparing between single vision lenses and functional progressive addition lenses, binocular visual function related near work, subjective satisfaction and preference was improved after wearing functional progressive addition lenses. This study suggested that functional progressive addition lenses were useful for long time near work.