• Journal of the Microelectronics and Packaging Society
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• v.10 no.3
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• pp.73-82
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• 2003

Recently, PWB(Printed Wiring Board) has been recognized in the field of microelectronic package as core technology for designing or manufacturing. PWB is the structure stacked by several materials with different thermophysical properties, which shows the different CTEs(Coefficient or Thermal Expansions) during the fabrication process and causes a lot of defects such as warpage, shrinkage, dimension, etc. Thermal deformation of PWB is affected mainly by the volume change of solder-resist among fabrication parameters. Therefore, thermal deformation of PBGA and CSP consisting of 2 layers and 4 layers was studied with solder-resist process. When over 30% in volume fraction of solder-resist, thermal deformation of 2-layered PWB was min. 40% higher than that of 4-layered PWB because 4-layered PWB contained the layer with high toughness such as prepreg, which counterbalanced the thermal deformation of solder-resist. Otherwise, when below 30%, PWB showed similar thermal deformation without regard to layers and design.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.1
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• pp.12-22
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• 2019

This paper presents a method to perform a more efficient electromagnetic wave analysis inside a large building by external electromagnetic waves. Topological analysis and the PWB method are introduced for electromagnetic wave analysis. In addition, a Performance-Enhanced PWB method, which complements the performance of the PWB method is proposed. A large virtual structure was selected and an analysis environment was set up to perform the electromagnetic wave analysis inside a large building from external electromagnetic waves. A commercially available software, Wireless Insite, was used to verify the accuracy of the the Performance- Enhanced PWB method. As a result of comparing the two results in terms of accuracy, time, and memory, We conclude that the Performance-Enhanced PWB method proposed in this paper is a more efficient method in a large bulding.

• Korean Journal of Human Ecology
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• v.17 no.2
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• pp.191-205
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• 2008

The study aims at exploring a general trend of psychological well-being (PWB) of elderly volunteers and analyzing the variables which give effects on their PWB. The subjects were two hundred men and women over 60 years old currently participating in voluntary service. The data collected from interviewing were analyzed by descriptive statistics, $x^2$ test, Pearson's correlation and hierarchical multiple regression. The main results are: First, PWB of the elderly is higher than the average score of PWB. Second, the elderly's generativity is positively related to PWB. Family support such as an emotional and instrumental support was also positively related to PWB. Third, the variables effecting on PWB of elderly volunteers were education level, participation frequency, generativity level, and an instrumental support of their family members on it. The lower their educational level was, the more frequently they participated in voluntary activity, the higher their generativity level was, and the more support given from their family, the higher PWB scores they showed.

• Journal of Families and Better Life
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• v.15 no.4
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• pp.149-164
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• 1997

This research examined the relationships of individual and intergenerational variables with psychological well-being(PWB) of elderly females and the relative significance of the effect of these variables on PWB. Structured interview technique was used to collect data from 202 elderly females in Seoul who were recruited through quota sampling method. Two-way analysis of variance result indicated that interaction effect between aged and the presence of spouse on PWB was existed. Though most variables were significantly correlated with PWB of elderly females results of multiple regression analyses indicated that three variables-self-efficacy self-esteem affectional solidarity with adult children- significantly influenced PWB and three variabels-coresiding with the first son's family satisfaction with pocket money and contact solidarity-approached the significance level to the effect on PWB.

• Safety and Health at Work
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• v.13 no.1
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• pp.66-72
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• 2022

Background: The aim of the present study was to evaluate the psychological well-being (PWB) during the coronavirus disease (COVID-19) pandemic in workers of a multinational company. Methods: Employees (aged ≥18 years) were recruited from Latin American, North American, New Zealand, and European sites of a multinational company operative during all the pandemic period. The self-reported Psychological General Well-Being Index was used to assess the global PWB and the effects on six subdomains: anxiety, depressed mood, positive well-being, self-control, general health, and vitality. The influencing role of age, gender, geographical location, COVID-19 epidemiology, and restrictive measures adopted to control the pandemic was explored. Results: A total of 1335 workers completed the survey. The aggregate median PWB global score was in a positive range, with significantly better outcomes detected in the Mexican and Colombian Latin American sites compared with the other worldwide countries (p < 0.001). Among the European locations, a significantly higher PWB score was determined in Spain compared with the German and French sites (p < 0.05). Comparable geographical trends were demonstrated for all the PWB subdomains. Male workers had a significantly better PWB compared with females (p < 0.05), whereas a negative correlation emerged with aging (p = 0.01). COVID-19 epidemiology and pandemic control measures had no clear effects on PWB. Conclusion: Monitoring PWB and the impact of individual and pandemic-related variables may be helpful to clarify the mental health effects of pandemic, define targeted psychological-supporting measures, also in the workplace, to face such a complex situation in a more constructive way.

• Journal of Digital Convergence
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• v.17 no.3
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• pp.361-369
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• 2019

The purpose of this study was to investigate the adaptation factor to North Korean refugees by identifying the relationship between character strengths affecting adaptation process and psychological well-being(PWB) in South Korea. The study examined the relationship between PWB and character strength of 117 participants and identified the sub-factors of character strength that affect the settlement period in South Korea. The data were analyzed by using the Model 1 of Process Macro and SPSS 22. The results of this study showed a correlation between PWB and sub-factors of character strength such as wisdom, humanity, courage, justice, temperance, and spirituality. The main effect was to investigate the relationship between PWB and sub-factors of character strength by independent variables. The level of PWB increased with the level of sub-factors of character strength. The moderate effect was showed in the courage of the settling period in relation to PWB. Finally, Limitations and implications of this study was discussed.

• Safety and Health at Work
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• v.14 no.3
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• pp.317-324
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• 2023

Background: COVID-19 pandemic represented a unique stressful event that affected the physical health and psychological well-being (PWB) of individuals and communities. Monitoring PWB is essential not only to clarify the burden on mental health effects but also to define targeted psychological-supporting measures. This cross-sectional study evaluated the PWB of Italian firefighters during the pandemic. Methods: Firefighters recruited during the pandemic period filled out a self-administered questionnaire, the Psychological General Well-Being Index, during the health surveillance medical examination. This tool is usually used to assess the global PWB and explores six subdomains: anxiety, depressed mood, positive well-being, self-control, general health, and vitality. The influencing roles of age, gender, working activities, COVID-19, and pandemic restrictive measures were also explored. Results: A total of 742 firefighters completed the survey. The aggregate median PWB global score was in the 'no distress"" range (94.3 ± 10.3), which was higher than that observed in studies conducted using the same tool in the Italian general population during the same pandemic period. Similar findings were observed in the specific subdomains, thus suggesting that the investigated population was in good PWB condition. Interestingly, significantly better outcomes were detected in the younger firefighters. Conclusion: Our data showed a satisfactory PWB situation in firefighters that could be related to different professional factors such as work organization and mental and physical training. In particular, our results would suggest the hypothesis that in firefighters, maintaining a minimum/moderate level of physical activity (consisting of even just going to work) might have a profoundly positive impact on psychological health and well-being.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.136-136
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• 2015

2007년 일본에서 지갑전화나 지상파 디지털TV 방송기능을 탑재한 휴대전화개발에 힘을 쏟고 있을 무렵, 해외에서 컴퓨터에 가까운 스마트폰이라는 다기능단말기 개발이 진행되고 있었다. 스마트폰은 젊은이를 중심으로 인기가 높아지고 있다. 휴대전화를 시작으로 정밀전자기기에는 인쇄배선판(이하, PWB: Printed Wiring Board)이 내장되어 있다. PWB는 향후 하이브리드차나 전기자동차의 발전과 함께, 차량탑재 수요도 높아질 것이다. 본고에서는 PWB를 지탱하는 동 도금 Via Hole메움에 대하여 기술하였다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.3
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• pp.337-347
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• 2013

It is generally well-known that the inevitable high power electromagnetic wave affects the malfunction and disorder of electronic equipments and serious damages in electronic communication systems. Hence, it is necessary to take measures against high power electromagnetic(HPEM) wave for protecting electronic devices as well as human resources. The topological analysis based on Baum-Liu-Tesche(BLT) equation simplifying the moving path of electromagnetic and the observation points and Power Balance Method(PWB) employing statistical electromagnetic analysis are introduced to analyze relatively electrically large cavity with little time consumption. In addition to the PWB method, full wave results for cylindrical cavity with apertures and incident plane wave are presented for comparison with time-consumption rate according to the cavity size.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.2
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• pp.189-197
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• 2013

With the trend of technological advances in electronic communications and the advent of ubiquitous environments, the density of existing electronic equipment in the surroundings is increasing significantly. It is hence great importance to study the numerically efficient and fast algorithm for complex and large environments to identify their electromagnetic compatibility and interference characteristics of equipments installed in those structure. This paper introduces a statistical-based power balance method(PWB) for the analysis of these problems and considers its practical utility. The 2-dimensional lossy rectangular cavity was numerically revisited to clarify its relationship with the classical deterministic analysis solutions based on the Maxwell's equation. It can be shown that the statistical assumptions and analysis results from the power balance method correspond to the volume average over the realistic deterministic domain. This statistical power balance approach should be a sufficiently practical alternative to the electromagnetic problem of complex and large environment since it is apparent that the full-wave analysis methods have some severe limits of its computational burdens under the situation of complex and large environment.