• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.2
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• pp.143-149
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• 2022

PCS needs to freely switch AC and DC to connect the battery, external AC loads and renewable energy in both directions for energy efficiency. Whenever converting happens, power loss inevitably occurs. Minimization of the power loss to save electricity and convert it for usage is a very critical function in PCS. PCS plays an important role in the ESS(Energy Storage System) but the importance of stabilizing semiconductors on PCB(Printed Circuit Board) should be empathized with a risk of failure such as a fire explosion. In this study, the temperature variation inside PCS was reviewed by cooling fan on top of PCS, and the vibration characteristics of PCS were analyzed during truck transportation for reliability of the product. In most cases, a cooling fan is mounted to control the inner temperature at the upper part of the PCS and components generating the heat placed on the internal aluminum cooling plate to apply the primary cooling and the secondary cooling system with inlet fans for the external air. Results of CFD showed slightly lack of circulating capacity but simulated temperatures were durable for components. The resonance points of PCS were various due to the complexity of components. Although they were less than 40 Hz which mostly occurs breakage, it was analyzed that the vibration displacement in the resonance frequency band was very insufficient. As a result of random-vibration simulation, the lower part was analyzed as the stress-concentrated point but no breakage was shown. The steel sheet could be stable for now, but for long-term domestic transportation, structural coupling may occur due to accumulation of fatigue strength. After the test completed, output voltage of the product had lost so that extra packaging such as bubble wrap should be considered.

• Child Health Nursing Research
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• v.29 no.2
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• pp.111-127
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• 2023

Purpose: This study investigated the effects of healthy lifestyle interventions (HLSIs) on health-related quality of life (HR-QoL) in childhood and adolescent cancer survivors (CACS). Methods: Major databases were searched for English-language original articles published between January 1, 2000 and May 2, 2021. Randomized controlled trials (RCTs) and non-RCTs were included. Quality was assessed using the revised Cochrane risk-of-bias tool, and a meta-analysis was conducted using RevMan 5.3 software. Results: Nineteen studies were included. Significant effects on HR-QoL were found for interventions using a multi-modal approach (exercise and education) (d=-0.46; 95% confidence interval [CI]=-0.84 to -0.07, p=.02), lasting not less than 6 months (d=-0.72; 95% CI=-1.15 to -0.29, p=.0010), and using a group approach (d=-0.46; 95% CI=-0.85 to -0.06, p=.02). Self-efficacy showed significant effects when HLSIs provided health education only (d=-0.55; 95% CI=-0.92 to -0.18; p=.003), lasted for less than 6 months (d=-0.40; 95% CI=-0.69 to -0.11, p=.006), and were conducted individually (d=-0.55; 95% CI=-0.92 to -0.18, p=.003). The physical outcomes (physical activity, fatigue, exercise capacity-VO₂, exercise capacity-upper body, body mass index) revealed no statistical significance. Conclusion: Areas of HLSIs for CACS requiring further study were identified, and needs and directions of research for holistic health management were suggested.

• Journal of the Korea Society for Simulation
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• v.19 no.3
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• pp.127-135
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• 2010

Modern marine navigation requires officers on the bridge to monitor a torrent of data on both the insides and outsides of the ship from numerous useful devices. But despite these tools, navigators can still find it difficult to make a safe decision for two reasons: one is that too much data if provided too quickly tends to cause fatigue and overwhelm the officer, and the other is that any inconsistency across data from several different types of devices can lead to confusion. Indeed, the fact remains that the many marine accidents can be attributed to human error, and hence there is a strong need for decision-support tools for marine navigation. One technique of providing decision support is through the use of simulation to evaluate or predict system dynamics over time using an accurate model. This paper, as a simulation method for risk prediction for a navigation safety information system of ship, suggests a navigation prediction simulation system using various knowledge bases and discrete event simulation methodology, and supports the validity of the system through the examples of components in a restricted navigation situation scenario.

• Women's Health Nursing
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• v.29 no.1
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• pp.32-43
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• 2023

Purpose: This study investigated the dietary behavior of experienced shiftwork nurses and aimed to identify factors related to dietary behavior. Methods: This study was a secondary analysis based on the Shift Work Nurses' Health and Turnover study (2018-2021) among Korean nurses. In total, 247 experienced (>12 months) shiftwork nurses were included in this study. The participants' dietary behavior, depression, level of occupational stress, fatigue, physical activity, and general characteristics were measured. Descriptive statistics, Pearson correlation coefficients, independent t-test, one-way analysis of variance, the Kruskal-Wallis test, and multiple regression analysis were conducted. Results: The dietary behavior score of the participants using the Mini-Dietary Assessment Index was 29.35±5.67. Thirty percent of the participants were depressed, the participants experienced moderate occupational stress, and 74.1% of the participants engaged in an inadequate amount of physical activity. The factors influencing shiftwork nurses' dietary behavior were having child(ren) (β=.16, p=.027), depression (β=-.13, p=.032), level of occupational stress related to occupational climate (β=-.13, p=.035), and an inadequate amount of physical activity (β=-.17, p=.006). These factors explained 10.4% of the variance in experienced shiftwork nurses' dietary behavior scores. Conclusion: Experienced nurses with child(ren) tended to have healthier diets. However, a higher level of occupational stress related to occupational climate, depression, and engaging in an inadequate amount of physical activity were associated with a higher risk of having an unhealthy diet. Therefore, strategies are needed to encourage physical activity and alleviate adverse occupational climate and depression among experienced nurses.

• Safety and Health at Work
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• v.15 no.1
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• pp.17-23
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• 2024

Background: The present study aimed to analyze several aspects of the working conditions and health status of platform workers in the Republic of Korea, such as ergonomic and emotional hazards. We also compared the health status of the platform workers with that of the general population. Methods: A total of 1,000 platform workers participated in this survey from August 7 to August 17, 2022. The participants included 400 designated drivers, 400 food-delivery drivers, and 200 housekeeping managers. A face-to-face survey with a structured questionnaire was conducted by researchers who had received specific instructions. The focus of the survey extended to the work environment, encompassing factors such as workplace violence, as well as physical, chemical, and ergonomic hazards. Health-related data for the previous year were also collected, covering a range of issues such as hearing problems, skin problems, musculoskeletal symptoms, headaches, injuries, mental health issues, and digestive problems. Subsequently, we compared the health symptom data of the responders with those of the general population in the Republic of Korea. Results: Platform workers, including designated drivers, food-delivery drivers, and housekeeping managers, existed in the blind spot of social insurance, facing frequent exposure to physical and chemical hazards, ergonomic risk factors, and direct or indirect violence. The prevalence of health problems, including musculoskeletal symptoms, general fatigue, and depressive symptoms, in each occupational group was statistically higher than that in the general population after standardization for age and gender. Conclusion: The results revealed unfavorable working environment and inferior occupational health of platform workers compared with those of the general population.

• Journal of Preventive Medicine and Public Health
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• v.57 no.1
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• pp.73-82
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• 2024

Objectives: The unsafe use of pesticides in agriculture represents a major hazard to human health. This study was conducted to investigate the association between pesticide exposure and health symptoms among chili farmers in northeast Thailand. Methods: This cross-sectional analytic study included 141 chili farmers in Sakon Nakhon Province, in northeast Thailand. Data regarding health symptoms were gathered using a self-report questionnaire. A medical technician tested blood cholinesterase activity using an erythrocyte method, and an occupational medicine specialist at Ramathibodi Hospital in Bangkok, Thailand reviewed the results. Associations between personal characteristics, pesticide exposure factors, and health symptoms were analyzed using multiple logistic regression. Results: Of the 141 chili farmers studied, 66.7% experienced pesticide poisoning, as indicated by below-normal cholinesterase levels. Fatigue was the most frequently reported symptom associated with pesticide exposure, affecting 37.6% of participants. This was followed by nausea and vomiting (31.9%), dizziness (14.9%), and dry throat (14.9%). Multivariate logistic regression analysis revealed that several factors were significantly associated with adverse symptoms: amount of work experience, volume of pesticides used, use of chemical pesticides, use of leaking containers during spraying, direct pesticide exposure while working, contact with pesticide-soaked clothing, consumption of food and drinks in the fields, and blood cholinesterase level indicating risk. Conclusions: This study suggests potential health risks for chili farmers stemming from exposure to and contamination by pesticides used in agricultural practices. To mitigate these risks, it is essential to supply personal protective equipment and to implement educational programs aimed at improving protective behaviors among farmers.

• International Journal of Advanced Culture Technology
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• v.12 no.1
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• pp.43-50
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• 2024

Patients with acute respiratory diseases, such as Middle East Respiratory Syndrome (MERS) due to COVID-19, must wear masks, protective clothing, face shields, and gloves to prevent infection during treatment and performance. Even if it is applied to disabled people, families who protect them are severely mentally tired from severe physical fatigue and stress from exposure to high-risk infectious diseases. As such, the spread of infectious diseases such as respiratory diseases has not only caused difficulties in using existing welfare and medical services but also caused various problems throughout the daily life of disabled people due to the prolonged infectious disease, and its scope is gradually expanding. Therefore, it should not be overlooked that disabled people may experience various difficulties, from the spread of infectious diseases such as respiratory diseases to isolation, diagnosis, and treatment, and it is time to actively assess the life changes felt by families caring for disabled people and consider and research to provide adequate services. According to the survey of disabled people is being conducted in the context of the spread of infectious diseases such as respiratory diseases, while research on the spread of infectious diseases such as respiratory diseases is rare for parents with disabilities. There is a need for additional investigation into the characteristics in other areas of everyday life, including the health field, which is deteriorating through prior research. Therefore, through this survey, the purpose of this study is to investigate the life changes of parents with disabilities in the context of the spread of infectious diseases such as respiratory diseases and to compare and analyze them to find out how parents were affected by each type of disability. It will be used as evidence to identify more necessary needs and problems for parents with disabilities in the spread of infectious diseases such as respiratory diseases and to provide more appropriate health care and welfare services in the future.

• Journal of Korean Academy of Nursing
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• v.20 no.2
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• pp.131-141
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• 1990

Recently, the rate of cesarean section in Korea has been increasing. The results of several previous studies in foreign countries on the emotional responses of cesarean section mothers showed that they might experience difficulties in the mother- infant interaction due to fatigue, lack of early mother - infant interaction, disappointments, anger, feelings of loss of control, and other factors. Human behavior is said to be determined by one's self concept, and self concept is influenced by both internal and external environmental factors. A scale to measure the self concept of cesarean section mothers was needed in order to identify those who might have difficulties in the mother- infant interactions in future. The purposes of this study were to develop a measuring scale, and to test its reliability and validity. The process of this study was as follows. A structured interview was done with 50 cesarean section and vaginal delivery mothers to find their state of emotional reaction after giving birth to their babies. Based on the results of the interviews, a 50 items Likert scale was developed. The self concept of 268 cesarean section and vaginal delivery mothers who were hospitalized at six hospital in seoul were measured, during the period between Feb. 1 and April 30. Reviewing the discriminating power of each item by means of crosstabulation, ten items were selected for the final scale. The reliability and validity of this ten item scale were tested by Cronbach's alpha and t-test, using spss pc＋package. The results of this study and recommendation are as follows. 1. The ten selected items were as follows. I feel pains in my breast. (－) I have a good appetite now. (＋) I feel pains in my flank. (－) I feel fine now. (＋) My body seems to have returned to its prepregnant state. (＋) Thinking of the delivery process, I feel sorry. (－) I want to hold my baby in my arms. (＋) I want to keep my own life, even if I became a mother. (－) I want to delegate the care of the baby to my mother / mother in law. (－) I think baby is my alter ego. (＋) 2. The reliability of this scale was tested by Cronbach's alpha, and the coefficient of this scale was .8066. 3. The construct validity of this scale was tested by means of known group methods. The value of self concept for cesarean section mother was significantly lower than for vaginal delivery mothers(t＝-5.51, df＝266, p＝0.007). 4. The criterion validity of this scale was tested indirectly. Though this scale could discriminate the differences in the self concept between cesarean section and vaginal delivery mothers, the five items on the personal self concept scale didn's show any differences between cesarean section and vaginal delivery mothers. Therefore, the study indicates that those who shows lower values in the personal self concept measurement, that is, lower than 12.03 points, could be regaled as “risk mothers” 5. Further studies using this scale to clarify the influencing factors on negative self concept are strongly recommended.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3903-3907
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• 2013

Background: Patients with colorectal cancer are usually treated with chemotherapy, which reduces the number of blood cells, especially white blood cells, and consequently increases the risk of infections. Some research studies have reported that aromatherapy massage affects the immune system and improves immune function by, for example, increasing the numbers of natural killer cells and peripheral blood lymphocytes. However, there has been no report of any study which provided good evidence as to whether aromatherapy with Thai massage could improve the immune system in patients with colorectal cancer. The objectives of this study were to determine whether the use of aromatherapy with light Thai massage in patients with colorectal cancer, who have received chemotherapy, can result in improvement of the cellular immunity and reduce the severity of the common symptoms of side effects. Materials and Methods: Sixty-six patients with colorectal cancer in Phichit Hospital, Thailand, were enrolled in a single-blind, randomised-controlled trial. The intervention consisted of three massage sessions with ginger and coconut oil over a 1-week period. The control group received standard supportive care only. Assessments were conducted at pre-assessment and at the end of one week of massage or standard care. Changes from pre-assessment to the end of treatment were measured in terms of white blood cells, neutrophils, lymphocytes, CD4 and CD8 cells and the CD4/CD8 ratio and also the severity of self-rated symptom scores. Results: The main finding was that after adjusting for pre-assessment values the mean lymphocyte count at the post-assessment was significantly higher (P=0.04) in the treatment group than in the controls. The size of this difference suggested that aromatherapy with Thai massage could boost lymphocyte numbers by 11%. The secondary outcomes were that at the post assessment the symptom severity scores for fatigue, presenting symptom, pain and stress were significantly lower in the massage group than in the standard care controls. Conclusions: Aromatherapy with light Thai massage can be beneficial for the immune systems of cancer patients who are undergoing chemotherapy by increasing the number of lymphocytes and can help to reduce the severity of common symptoms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.446-457
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• 2019

The purpose of this study was to analyze the association between family members and adolescent boys smoking. The data were evaluated by frequency analysis, 𝑥² test and logistic regression analysis using 27,276 people who responded to the 14th(2018) Korean Youth Risk Behavior Survey. Among male students, the nonsmoking rate was 91.5% and the smoking rate was 8.5%(2.5% of occasional smoking and 6.0% of frequent smoking). The study results showed that the smoking status of male students was varied significantly according to the number of smokers among the family members(p<0.001). Meanwhile, smoking based on the characteristics of socio-demographic factors was affected by grades, school records, economic status, and parents' educational background(p<0.001). Smoking by health factors showed a significant difference in alcohol consumption, suicidal thoughts, depression experiences, stress recognition, frequency of breakfast consumption, level of fatigue after sleep, and subjective perception of health(p<0.001). Male smokers were more likely to smoke when two family members smoked than only one(p<0.001). These results confirmed that smoking in boys was affected by the smoking status of family members and suggested that the smoking cessation program of family smokers can be effective in designing smoking cessation prevention and smoking cessation projects.