• Journal of the Microelectronics and Packaging Society
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• v.29 no.3
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• pp.55-61
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• 2022

In this study, properties of Pb-free solder joints which were combined using Sn-3.0Ag-0.5Cu (SAC305) Pb-free solder with a mid-temperature type of melting temperature and Sn-57Bi-1Ag Pb-free solder with a low-temperature type of melting temperature were reported. Combined Pb-free solder joints were formed by reflow soldering processes with ball grid array (BGA) packages which have SAC305 solder balls and flame retardant-4 (FR-4) printed circuit boards (PCBs) which printed Sn-57Bi-1Ag solder paste. The reflow soldering processes were performed with two types of temperature profiles and interfacial properties of combined Pb-free solder joints such as interfacial reactions, formations of intermetallic compounds (IMCs), diffusion mechanisms of Bi, and so on were analyzed with the reflow process conditions. In order to compare reliability characteristics of combined Pb-free solder joints, we also conducted thermal shock test and analyzed changes of mechanical properties for joints from a shear test during the thermal shock test.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.115-125
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• 2020

Housing issues such as mushrooming slums remain as chronic in most developing countries. Due to the state's restrained capacity, the housing-vulnerable's self-help approaches have been increasingly inevitable and vital for addressing the housing issues. However, there are still two challenges: securing good quality with economic efficiency, and climate change mitigation and adaptation. This study aims at doing an architectural experiment by developing and educating the production of eco-friendly interlocking stabilized soil bricks (ISSB) by employing vernacular materials and technologies for housing-vulnerable communities in Indonesia. In collaboration with a local architectural NGO, the study features a co-creation workshop in which 40 evicted households participate in the whole process. Soil analysis, mixed design, compression tests, and economic analysis are carried out. This paper illustrates that ISSB also has a high potential as an alternative to a burned brick or a cement block. The application of ISSB to self-help housing is expected to have socioeconomic and environmental effects, thereby facilitating the housing-vulnerable's self-help approaches and contributing to addressing the housing challenges in Indonesia.

• Journal of Physiology & Pathology in Korean Medicine
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• v.35 no.3
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• pp.97-103
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• 2021

Perilla frutescens (P. frutescens) is an important herb used for many purposes such as medicinal, aromatic, and functional food in Asian countries and has beneficial effects such as antioxidant activity, anti-inflammation activity, anti-depression activity, and anxiolytic activity. However, there have been no studies on the protective effect of P. frutescens extract (PFE) on amnesia in vivo. The present study aimed to investigate whether PFE protects memory deficit using a scopolamine-induced mice model and elucidate the underlying mechanisms involved. The protective effect of PFE against scopolamine-induced memory deficits was investigated using Y-maze, passive avoidance, and Morris water maze tests. Furthermore, the potential mechanisms of PFE in improving memory capabilities related to the cholinergic system and antioxidant activity were examined. PFE significantly increased spontaneous alternation in the Y-maze test, step-through latency in the passive avoidance test, and swimming time in the target quadrant in the probe test when compared to the scopolamine-treated group. Likewise, PFE significantly decreased escapes latency in the Morris water maze test. PFE could not regulate cholinergic function in acetylcholine level and acetylcholine esterase activity. However, PFE increased DPPH radical scavenging activity dose-dependently and total polyphenol content was 127.7±1.2 ㎍ GAE/mg. The results showed that the PFE could be a preventive and/or therapeutic candidate for memory and cognitive dysfunction in Alzheimer's disease.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.207-215
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• 2021

A forklift is an industrial vehicle with a power-operated fork for lifting and moving heavy loads over short distances. A significant number of accidents are caused by forklifts every year. Most of them are known to be caused by the unsafe acts of workers. However, only a few studies have focused on the risks of forklift work from the perspective of human error. In addition, various methods have been developed to analyze the risk of human error, while it is hard to find studies that directly compare the effectiveness or strengths/weaknesses of those methods. This study aims to analyze risk factors related to unsafe behavior in forklift operations using two representative human error analysis techniques, i.e., .SHERPA and HE-HAZOP, and compare their advantages and disadvantages. The analysis was performed on three main forklift operations ('unloading from the truck', 'moving and loading into the storage', and 'loading on the truck'). As a result, 118 errors and 34 remedial measures were derived by SHERPA. Through HAZOP, 139 errors and 54 measures were derived. The two techniques were compared in terms of the number of results and the method of deriving errors and remedial measures, cause analysis, and risk assessment. This study might be used to reduce human error related disasters in workplaces using forklifts. In order to provide a guide for choosing an appropriate analysis method, more comparative studies on different techniques involving wide range of tasks are needed in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.207-220
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• 2021

This study aimed to evaluate the impact of education and counselling by nurses on anxiety, uncertainty, and pain in patients with benign uterine tumors. Electronic databases, including PubMed, OVID, CINAHL, Google Scholar, and Korean databases and were searched during January 2020. A total of 401 studies were identified of which 13 were suitable for meta-analysis. Cochrane's risk of bias tool and the R version 3.5.2 (Meta-analysis with R) program were used for analysis. The authors performed a meta-analysis of the 13 trials that met eligibility criteria. The findings in this study indicate that the effect size of nursing education for anxiety was Hedges' g=-0.89 (95% CI:-1.39 to -0.47), as indicated by a "large effect size" and the effect size of pain was Hedges' g=-0.49 (95% CI:-0.95 to -0.02) as indicated by a "moderate effect size". The effect size of uncertainty was Hedges' g=-1.38 (95% CI:-3.98 to 1.23), and it was not statistically significant. In the meta-subgroup analyses by approach intervention type, cognitive-behavioral programs, demonstration intervention, and relaxation therapy had a significant effect. The risk of publication bias was low. It may therefore be concluded that pre-operative education by nurses for patients with benign uterine tumors would affect their levels of anxiety, uncertainty, and pain.

• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.143-153
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• 2021

Purpose: The purpose of this study was to analyze data from the Ministry of Health, Safety and Health and the Ministry of Employment and Labor, and the total number of deaths (disease + accidents) reached 2,020 in 2019 and the estimated economic loss was 27.6 trillion won. This is believed to be the time to present improvements to ensure that economic loss estimates are steadily increasing as in Table 1, and that government-level losses can be drastically reduced. Method: In this study, factors were selected through prior research, and reliability analysis, technical statistics and correlation analysis, and multi-term analysis were conducted through the Jamovi program for the analysis of results. Result: Multiple session analysis was conducted to verify the research theory indicated in this study, and the analysis showed that mechanical and management factors did not affect the fall death accident of the opening, and human factors, material and environmental factors had a static effect. In addition, mechanical and administrative factors do not affect the fall of the outer wall, and human and material and environmental factors have a static effect. Conclusion:: As a result of analyzing 450 falling deaths over the past 13 years among the data posted to the Korea Health and Safety Corporation, the most common causes of falling deaths were the openings and outer walls.

• PNF and Movement
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• v.19 no.1
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• pp.115-125
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• 2021

Purpose: This study aimed to investigate basic data on the recognition of rehabilitation robots and self-efficacy through general characteristics of students in the department of physical therapy. Methods: This study surveyed 100 students in the Department of Physical Therapy at E University in Seongnam using Google Form, an online survey tool. The questionnaire consisted of 64 questions including 15 questions on general characteristics, 13 questions regarding recognition of rehabilitative robots, and 36 questions about self-efficacy. General self-efficacy consisted of three sub-factors: confidence, self-regulation efficacy, and task difficulty preference. Results: The recognition of rehabilitative robots according to general characteristics showed significant differences in age, level of education, and experience in searching rehabilitative robots; according to general characteristics, self-efficacy showed significant differences dependent on age and gender (p < 0.05). In addition, recognition of rehabilitation robots for students in the Department of Physical Therapy was found to have a significant effect on robot use self-efficacy (p < 0.05). Conclusion: There were significant differences in the scores of rehabilitation robot recognition and self-efficacy according to the general characteristics of students in the Department of Physical Therapy. For such reasons, it is important for students to have an opportunity to get educated on rehabilitation robots; in order to achieve this goal, domestic studies on rehabilitation robots must be actively conducted. The technological development of rehabilitation robots and the establishment of a system for domestic rehabilitation robots from both social and legal standpoints were found to be necessary based on a volume of domestic research.

• Tuberculosis and Respiratory Diseases
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• v.84 no.2
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• pp.105-114
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• 2021

Background: Complementary and alternative medicine (CAM) has been used frequently, and its use continues to increase in lung cancer patients, despite insufficient scientific of its efficacy. To investigate this situation, we analyzed the current awareness and use of CAM in Korean lung-cancer patients. Methods: This prospective survey-based study was performed at seven medical centers in South Korea between August and October 2019. The survey assessed general patient characteristics and the awareness and use of CAM. We analyzed differences in the clinical parameters of patients aware and not aware of CAM and of CAM non-users and users. Results: Of the 434 patients included in this study, 68.8% responded that they were aware of CAM and 30.9% said they had experienced it. In univariate analysis, the patients aware of CAM were younger with poor performance status, had advanced-stage lung cancer, received more systemic therapy, and received concurrent chemoradiation therapy (CCRT). By multiple logistic regression, younger age, poor performance status, advanced stage, and prior CCRT were identified as independent risk factors for CAM awareness. There were no significant differences in the general characteristics and cancer-associated clinical parameters of CAM non-users and users. Conclusion: Specific clinical parameters were associated with patients' awareness of CAM, although there were no significantly different characteristics between CAM users and non-users.

• Journal of Korea Trade
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• v.24 no.6
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• pp.135-156
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• 2020

Purpose - This study investigates whether the internationalization process of traditional industry firms can be categorized as born global, early internationalization, or gradual internationalization, and examines what factors promote internationalization in traditional industries using a case study of two firms, one each in China and Korea. Design/methodology - This study elects to use case study methodology to determine the "how" and "why" of internationalization process of traditional industry firms. Taking into consideration that factors that impact the internationalization process of firms are diverse and unclear in terms of causality, this study utilizes exploratory case study methodology. This research performs a comparative two-case study of two firms in traditional industries, one each in China and Korea, to examine similarities and differences of study subjects in order to improve the validity and suitability of research results. Findings - The findings of this research are as follows: First, traditional industries are more likely go through early and rapid internationalization rather than being born global; born globals are far more likely to appear in high tech industries. Second, the internationalization process of companies that go through early and rapid internationalization differs from what is indicated by traditional internationalization theories, and are not limited by factors like psychological distance and lack of experiential knowledge. Third, international entrepreneurship, international market orientation, and imitation and learning are important internal driving factors for early and rapid internationalization. Fourth, conditions within the domestic market, policy support from the government, and pilot effect from industry leaders are external driving factors for early and rapid internationalization. Originality/value - This study shows that the internationalization process of traditional industry firms is more likely to be early and rapid internationalization rather than being born global and suggests answers to why this may be the case. In addition, through an examination of case studies, it reveals that the internationalization process of traditional industry firms that undergo early and rapid internationalization is different from traditional internationalization theory, in that they are not limited by the lack of psychological proximity and empirical knowledge, and are driven by international entrepreneurship, international market orientation, imitation and learning, competitive pressure within the domestic market, government's policy support, and the pilot effect of industry leaders. Therefore, this study contributes to literature by expanding the scope of application of born global theory to traditional industries, making born global theory more generalizable and identifying driving factors to internationalization of traditional industry firms.

• Journal of the Korean Chemical Society
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• v.65 no.4
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• pp.279-295
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• 2021

The purpose of this study was to investigate the effect of Character-centered instruction model on pre-service science teachers' awareness of both character education and character education in science education. First of all, pre-questionnaires about the sixteen pre-service science teachers' awareness of character education and character education in science education were asked. Through the lectures during a semester, they received an education about CoProC(Collaborative Problem-Solving for Character competence) model using Character-centered instruction model and character education. After the implementation, their changes of awareness were inspected through post-questionnaires. As a result of the study, it was revealed that general pre-service science teachers' pre-awareness of character education was mostly negative. The pre-service science teachers were more aware of character education in science classes than general character education. Even that, there seemed to be a greater tendency to think in connection with specific content and subject matter and character education rather than developing competencies due to the nature of the science subject itself. However, the experiences of the CoProC model changed their perception about character into a competent point of view, and thus influenced the change in their perception of character education. Therefore, education on character education methods for pre-service science teachers at teacher training institutions will increase their expertise in character education and help establish effective character education in school in the long term.