• Journal of Electrochemical Science and Technology
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• v.13 no.1
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• pp.90-99
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• 2022

Owing to the rising concern of global warming, lithium-ion batteries have gained immense attention over the past few years for the development of highly efficient electrochemical energy conversion and storage systems. In this study, alpha-phase VOPO₄·2H₂O with nanosheet morphology was prepared via a facile hydrothermal method for application in high-performance lithium-ion batteries. The X-ray diffraction and scanning electron microscopy (SEM) analyses indicated that the obtained sample had an alpha-2 (αII) phase, and the nanosheet morphology of the sample was confirmed using SEM. The lithium-ion battery with VOPO₄·2H₂O as the anode exhibited excellent long-term cycle life and a high capacity of 256.7 mAh g^-1 at room temperature. Prelithiation effectively improved the specific capacity of pristine VOPO₄·2H₂O. The underlying electrochemical mechanisms were investigated by carrying out AC impedance, rate capability, and other instrumental analyses.

• Physical Therapy Rehabilitation Science
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• v.11 no.4
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• pp.436-445
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• 2022

Objective: Deformation of soft tissues around the neck and scapularcan caused by forward head posture(FHP), which has an uncomfortable effect on biomechanical changes in the scapula as well as functional disorders of the shoulder. However, studies related to direct FHP, biomechanical changes in the scapulafunction, and shoulder pain and disorder have not yet been conducted. Therefore, purpose of this study is to effect of decresedthe FHP on the shoulder function of the sacpular biomechanical examine the change in the shoulder painand disorder. Design: A randomized controlled trial Methods: The participants were 32adults(23.03±3.90 years) recruited and redivided randomly into Forward head posture corrective exercise(FHPCE) vs Control. The FHPCE group was proceeded according to the over load principle through 2steps biofeedback exercise and corrective exercise(n=16). The control (n=16) was TENS did not operated and padding 20 minute. This study was conducted 3 times a week for 4a weeks. Results: FHPCE group is improve in the results of craneocervical angle(p<0.05, 95% CI: 0.352, 4.073). In Mechanical changes of scapula in the shoulder flexion more significant improvement in FHPCE than control group[Axis X(p<0.05), Y(p<0.01), Z(p<0.01)], and shoulder abductionmore significant improvement in FHPCE than control group[xis X(p<0.01)], as well FHPCE showed significant increased in the results in the shoulder pain(p<0.05, 95% CI: -13.244, -1.566) Conclusions: This study suggected that FHP affects the biomechanical changes of the shoulder, and a new method for shoulder pain intervention

• Journal of Korean Public Health Nursing
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• v.23 no.2
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• pp.199-206
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• 2009

Purpose: This study was designed to compare health habit and self-rated health status among early adulthood women in 1995, 2001, and 2007. Also, it was performed to determine correlations between health habits and self-rated health status. Methods: This research was investigated to identify a transition of health habits and self-rated health status. Participants who agreed to participate in the study were 18~25years old college women. Data was collected from 380 college students in 1995, 196 college students 2001, and 411 college students in 2007. Health habit assessment questionnaire was developed by authors. The reliability of the questionnaire were Cronbach $\alpha$=.87. Cronbach $\alpha$=.85, Cronbach $\alpha$=.90. The visual analogue scale which had 100 self-rating scores was used. All statistical analyses were used the Statistical Package for Social Sciences for Windows, Statistical analyses included descriptive statistics, Levene's test, repeated measure ANOVA, Brown-Forsythe test, Turkey test, Games-Howell test, and Pearson correlation coefficient test. Results: Health habit level, and self-rated heath status were significantly increased over time after 1995. Health habits was correlated with self-rated health status. Conclusion: Health habits and self-rated health status were influenced by health environments. Health practitioner can use perceived health status to access health habits.

• KDI Journal of Economic Policy
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• v.45 no.4
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• pp.23-56
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• 2023

To investigate the causes of Korea's growth slowdown over the past thirty years, we estimate the contributions of major developmental factors, including i) demographic factors (changes in population growth and workforce age due to the demographic transition), ii) quality-of-life-related choice factors (changes in working hours, education, and the female employment rate), iii) structural change, and iv) the effects of productivity catch-up. Our estimates show that these four groups of factors account for approximately 90 percent of the growth slowdown, with demographic factors contributing approximately 30 percent and the other three groups of factors each contributing about 20 percent. We also show that the same factors explain most of Korea's high growth in the 1980s. These results suggest that Korea's growth slowdown is basically a consequence of its successful economic development and that the high growth and subsequent slowdown can be regarded as a single process. In addition, given that the factors examined here exhibit similar patterns of change in the course of economic development of most countries, we think that our estimation results of the relationship between economic development and changes in economic growth trends could have more general implications that go beyond Korea's experience.

• Earthquakes and Structures
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• v.26 no.1
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• pp.59-75
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• 2024

This paper presents a dam-reservoir interaction model that includes, water compressibility, sloshing of surface water, and radiation damping at the far-end reservoir, to investigate the influence of concrete deterioration on seismic behavior along with seismic performance of gravity dams. Investigations on seismic performance of the dam body have been conducted using the linear time-history responses obtained under six real and 0.3 g normalized earthquake records with time durations from 10 sec to 80 sec. The deterioration of concrete is assumed to develop due to mechanical and chemical actions over the dam lifespan. Several computer programs have been developed in FORTRAN 90 and MATLAB programming languages to analyze the coupled problem considering two-dimensional (2D) plane-strain condition. According to the results obtained from this study, the dam structure shows critical responses at the later ages (75 years) that could cause disastrous consequences; the critical effects of some earthquake loads such as Chi-Chi with 36.5% damage and Loma with 56.2% damage at the later ages of the selected dam body cannot be negligible; and therefore, the deterioration of concrete along with its effects on the dam response should be considered in analysis and design.

• Journal of Drive and Control
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• v.21 no.1
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• pp.16-21
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• 2024

The yaw gearbox is a key device in a wind power generator that improves power generation efficiency by rotating hundreds of tons (400 to 600 tons) of nacelle so that the blade reaches 90 degrees in the wind direction. Recently, installation sites have been advancing from land to sea as they have become super-large at (8-12) MW to increase the economic feasibility of wind power generators and utilize excellent wind resources, and the target life of large wind power generators is 25 to 30 years. The yaw gearbox of 6 to 12 sets is installed in a very complex place inside the nacelle on the tower with parallels, and it is important to secure the reliability of the yaw gearbox because if a failure occurs after installation, it costs tens to hundreds of times the price of a new product to restore. In this study, equivalent loads were calculated by analyzing failure mode and field data, accelerated life test conditions were established, and a test device was constructed to perform the accelerated life tests and performance tests to ensure the reliability of the gearbox.

• Journal of agricultural medicine and community health
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• v.35 no.3
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• pp.314-325
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• 2010

Objectives: The purpose of this study was to investigate the effects of pet dog-assisted activities on self-esteem, depression and cognitive function of elderly people Method: The experimental group(pet dog-assisted group) consisted of 22 people over 65 years old out of about 90 elderly people registered with a home for the aged and the control group(non-pet dog assisted group) consisted of 22 people over 65 years old out of about 90 elderly people registered with another home for the aged in Daegu. Both groups had similar general characteristics, state of health, conduct on health and self-esteem, depression and cognitive abilities. Nineteen people who participated in the program at least 10 times out of 12, were chosen for the final analysis from the experimental group. For the control group, 20 people who responded to all three tests, which had been conducted before, 1 week after, and four week after the experiment, were analyzed. Result: Mean(${\pm}SD$) differences between before and 1 week after the experiment for self-esteem, depression, and cognitive function were 5.84(${\pm}3.06$), -3.26(${\pm}1.76$), 1.47(${\pm}1.26$), respectively. Those between before the experiment and 4 weeks after the experiment was 5.68(${\pm}3.64$), -3.94(${\pm}2.32$), 1.63(${\pm}0.96$), respectively. Those for control group between before and after the experiment were -0.40(${\pm}1.27$), 0.00(${\pm}0.92$), 0.15(${\pm}0.93$), respectively. Those for control group between before and 4 weeks after the experiment were -0.45(${\pm}2.24$), 0.25(${\pm}1.68$), 0.15(${\pm}0.93$), respectively. All the differences between experiment and control group in mean differences between before and 1 week after experiment, between before and 4 weeks after experiment were statistically significant(p<0.05). Conclusion: This study suggests that the pet-assisted activities can be useful solution for elderly people who have psychological and emotional problems caused by retrogression of physical, mental and social ability.

• Journal of agricultural medicine and community health
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• v.27 no.1
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• pp.165-181
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• 2002

The purpose of this survey was to assess the nutritional status of preschool children a county of Jeju Island. This study used health examinations results for preschool aged children, performed by the public health center of Pukjeju-gun in Jeju-do for over three years from 1999 to 2001, of children in kindergartens and children homes. The target children totaled 5,990 from the ages three to six. For a control group, 316 children from the nearby Jeju-city areas were included as well. The items of this research included height, weight, and hemoglobin values. 1. The average height of boys from ages three to six were 96.35cm, 102.14cm, 109.94cm, 111.00cm respectively, and girls were 94.96cm, 100.93cm, 108.33cm, 110.54cm respectively. The average weights of boys from ages three to six were 15.42kg, 16.93kg, 19.65kg, 19.67kg respectively, and the weight of girls were 14.90kg, 16.45kg, 18.88kg, 19.50kg respectively. 2. The percentages of children who did not reach 90% of the Korean standard height were 4.3% in boys 4.1% in girls. The percentages of children with less than 80% of the Korean standard weight were 7.6% in boys and 6.8% girls. The percentages of children over 120% of Korean standard weight were 10.4% in boys and 11.4% in girls. 3. As for the obesity level, the percentage of boys under-weighed(under 10% for standard weight for height) were 11.6% and girls, 9.5%, and the percentages of boys and girls with obesity($\geq$20%) were 3.6% and 4.4% respectively. 4. The mean hemoglobin value of boys were 11.83g/$d\ell$ and girls, 11.83g/$d\ell$. These were lower than the value of average normal Korean children (12.5g/$d\ell$). The mena hemoglobin values of the children in Pukjeju-gun were considerably lower than that of the children living in Jeju-city(12.3g/$d\ell$) as well. Anemia of Children of Pukjeju-gun were estimated at 38.1%(male) and 37.2%(female), by using Hemoglobin level(<11.5g/$d\ell$ 5. The rates of children included within the normal range of obesity level in Jeju-city and Pukjeju- gun were boys 80.2%, 71.6% in boys, and 77.4%, 72.4% in girls. The percentage of children living in PukJeju-gun included within the normal range were considerably low. 6. There were no changes in the Body Mass Index (BMI) during the three years from 1999 to 2001, but the percentage of children with anemia significantly increased. Health care for preschool aged children, especially in the rural areas, is very important. Centering on public health centers, it is necessary to systematically promote health care in the rural areas.

• Journal of Chest Surgery
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• v.48 no.4
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• pp.252-257
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• 2015

Background: Lobectomy is the generally accepted standard treatment for early-stage non-small cell lung cancer (NSCLC). However, especially in elderly patients, it is often necessary to perform pneumonectomy in order to maximize the likelihood of curative treatment, although pneumonectomy is a challenging procedure. Methods: We analysed patients who were clinically diagnosed with stage I NSCLC and underwent pneumonectomy with curative intent from 2004 to 2011. The patients were divided into an elderly group (${\geq}70$ years) and a younger group (<70 years). We retrospectively analysed the outcomes of these groups of patients in order to characterize the role of pneumonectomy as a treatment for elderly patients with clinical stage I NSCLC. Results: Thirty patients younger than 70 years of age (younger group) and fourteen patients 70 years of age or older (elderly group) who underwent pneumonectomy were enrolled in the present study. The median follow-up period was 35 months (range, 0 to 125 months). The perioperative mortality rate (within 90 days after the operation) was 7.1% in the elderly group and 6.7% in the younger group (p=0.73). No significant differences between the two groups were observed regarding the occurrence of pneumonia, acute respiratory distress syndrome, cardiac arrhythmia, bronchopleural fistula, and vocal cord paralysis. The overall five-year survival rate was 79.4% in the younger group and 35.7% in the elderly group, which was a significant difference (p=0.018). The five-year disease-free survival rate was 66.7% in the younger group and 35.7% in the elderly group, but this difference was not statistically significant (p=0.23). Conclusion: Although elderly patients with early stage lung cancer showed a worse long-term survival rate after pneumonectomy than younger patients, the outcomes of elderly patients were similar to those of younger patients in terms of perioperative mortality and postoperative complications. Patients should not be denied pneumonectomy solely due to old age.

• Journal of the Korean Society of Food Culture
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• v.13 no.4
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• pp.327-337
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• 1998

A Survey was carried out to investigate relation between depressive trends, stress and attitudes of food intake in adults. In the assessing of Body Mass Index (BMI), the normal weight was 80.1%, overweight was 19.1%, obese was 0.7% in men, but normal weight was 90.3%, overweight was 9.4%, obese was 0.3% in women (p<0.001). It was represented increasing trends of obesity by the increasing of ages. Women thought their health condition was worse than men (p<0.001) 15.1% of all women tried to weight control. In changes of food intake by stress, 37.8% was increased to eat, 33.7% was reduced in women. It seems that women was significantly influenced by stress than men (p<0.01). In changes of food intake by stress in ages, 39.7% was increased of 20 years but over the 30 years was decreased or no changes of food intake (p<0.0001). All subjects wanted hot and sweet taste when stress-induced eating. 56.1% of men preferred to alcohol and beverages but 33.5% of women preferred to chocolate, cookies and breads of carbohydrate foods at the stressful conditions. But stress-induced eating dose not seems to be helpful for coping with stress in adults. In the distribution of depressive trends, the level of depression was higher in women (50.7%), whereas 34.3% in men (p<0.001). The most of 3li subjects represented attitudes of food intake below 60 scores that was needed improve and counseling of professional nutritionist. It was represented inferior to attitudes of food intake by the increasing of depressive trends and stress in women. It was higher level of overweight and obese in the below 60 scores of attitudes of food intake and higher depressive groups.