• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.7 s.124
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• pp.572-578
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• 2007

Two stroke low speed diesel engines are widely used for marine propulsion or as power plant prime mover. These engines have many merits which includes higher thermal efficiency, mobility and durability. Yet various annoying vibrations occur sometimes in ships or at the plant itself. Of these vibrations, torsional vibration is very important and dictates a careful investigation during the engme's initial design stage for safe operation. With the rule and limit on torsional vibration in place, shaft strength fatigue due to torsional vibration however demands further analysis which possibly can be incorporated in the classification societies' rule and limit. In addition, the shaft's torsional vibration stresses can be calculated equivalently from accumulated fatigue cycles number due to transient torsional vibration in time domain. In this paper, authors suggest a new estimation method combined with Palmgren-Miner equation. A 6S70MC-C ($25,320ps{\times}91rpm$) engine for ship propulsion was selected as a case study. Angular velocity was measured, instead of shaft's strain, for simplified measurement and it was converted to torsional vibration stress for accumulated fatigue cycle numbers in shafting life time. Likewise, the accumulated fatigue calculation was compared with shaft fatigue strength limit. This new method can be further realized and confirmed in ship with two stroke low speed diesel engine.

• Journal of the Korean GEO-environmental Society
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• v.7 no.6
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• pp.89-100
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• 2006

Recently, lots of lives and properties have been lost because comparatively large magnitude earthquakes were occurred in relatively safe regions and nations. It has been reported that number of earthquakes was increased rapidly in Korea. Hence, recently civil constructions were ensured against risks about earthquake not only large-scale structures but also comparative small-scale structures such as reservoir dams and life line by systematic aseismic design. Therefore, in this study, the seismic stability was ensured to evaluate aseismic performance for major planned reservoir dams in Korea. The seismic response analyses were conducted using SHAKE program on new reservoir dams under short-period, long-period and artificial seismic wave. The liquefaction potential for reservoir dams was assessed by using results from seismic response analysis (simplified assessment method for liquefaction potential). Also, fully coupled analysis--interaction of pore-pressure and soil--was performed to investigate both the development of excess pore water pressure and the characteristic of dynamic shear strain.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.267-267
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• 2016

Extreme events, such as Winnie(1987), Rusa(2002), Maemi(2003) at sea-side urban area, resulted not only economic losses but also life losses. The Korean sea-side characterisitcs are so complicated thar the prediction of sea level rise makes difficult. Geomophologically, Korean pennisula sits on the rim of the Pacific mantle so the sea level is sensitive to the surges due to earth quake, typoon and abnormal climate changes. These environmetns require closer investigation for the preparing the inundatioin due to the sea level rise with customized prediction for local basin. The goal of this research is provide the information of inundation risk so the sea side urban basin could be more safe from the natural water disastesr.

• Safety and Health at Work
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• v.6 no.4
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• pp.317-323
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• 2015

Background: Young people are at an increased risk for illness in working life. The authorities stipulate certain goals for training in occupational health and safety (OHS) in vocational schools. A previous study concluded that pupils in vocational education had limited knowledge in the prevention of health risks at work. The aim of the current study, therefore, was to study how OHS training is organized in school and in workplace-based learning (WPL). Methods: The study design featured a qualitative approach, which included interviews with 12 headmasters, 20 teachers, and 20 supervisors at companies in which the pupils had their WPL. The study was conducted at 10 upper secondary schools, located in Central Sweden, that were graduating pupils in four vocational programs. Results: The interviews with headmasters, teachers, and supervisors indicate a staggered picture of how pupils are prepared for safe work. The headmasters generally give teachers the responsibility for how goals should be reached. Teaching is very much based on risk factors that are present in the workshops and on teachers' own experiences and knowledge. The teaching during WPL also lacks the systematic training in OHS as well as in the traditional classroom environment. Conclusion: Teachers and supervisors did not plan the training in OHS in accordance with the provisions of systematic work environment management. Instead, the teachers based the training on their own experiences. Most of the supervisors did not receive information from the schools as to what should be included when introducing OHS issues in WPL.

• The Journal of Internal Korean Medicine
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• v.43 no.3
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• pp.375-386
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• 2022

Objectives: The purpose of this study was to summarize current clinical study trends and results regarding transcutaneous electrical nerve stimulation (TENS) treatment for xerostomia. Methods: Studies published from 2017 to 2022 were searched on domestic databases and PubMed. The included studies were analyzed according to the year, language, study design, diagnosis xerostomia method, and TENS treatment method. Results: Nine studies were included. There were three randomized controlled trials (RCTs), three case series, one case report, one case-control study, and one cross-sectional study. Conventional TENS was used in seven studies, and acupuncture-like TENS (ALTENS) was used in one study. The most common TENS attachment site was externally on the skin overlying the parotid gland region, and the setting of TENS was 50 Hz-250 μs the most. In all nine studies, TENS was effective for xerostomia as assessed by salivary flow rate or quality of life questionnaire. Additionally, no persistent adverse events were reported after TENS treatment. Conclusions: TENS treatment for xerostomia can be considered effective and safe, so it can be used in clinical practice.

• Journal of Wellbeing Management and Applied Psychology
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• v.6 no.4
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• pp.41-50
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• 2023

Purpose: As life expectancy increases and interest in oral health increases, the opportunity to visit the dentist increases. To provide safe dental care for elderly patients and accurately identify their needs. We aim to understand the impact of knowledge, image, and empathy for the elderly on communication skills. Research design, data, and methodology: This study conducted an online survey using a convenience sample of 201 dental hygienists working in dental hospitals and clinics from October 4 to October 6, 2023. The purpose of the survey was explained and consent was obtained in the research consent form before being conducted. Results: Differences in knowledge, image, empathy, and communication skills among the elderly include age, clinical experience, need for elderly-related education, and confidence in oral care in elderly patients with systemic diseases (p<0.05, p<0.01, p<0.001). The factor affecting communication skills toward the elderly was empathy (t=15.416(0.000^***)). Conclusions: Through this study, the communication skills with the elderly is a basic quality and attitude that dental hygienists must have. Therefore, it is essential to develop and implement empathy and communication skills training programs for dental hygienists, which can significantly contribute to fostering a positive trust-based relationship between elderly patients and dental professionals. This proactive measure is crucial in preparing for the upcoming era of an increasingly aged society.

• Human Ecology Research
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• v.62 no.2
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• pp.351-368
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• 2024

The objectives of this study were to develop, implement a home economics education teaching-learning plan and assess its effects to enhance global citizenship competencies among upper elementary school students. The ADDIE model was employed for learner needs analysis, instructional design, development and implementation. This was followed by assessments of global citizenship competencies and class satisfaction. Based on an analysis of the core ideas associated with an area of "Living Environment and Sustainable Choice," four practical problems were designed: What actions should I take for the rational management of living resources? What actions should I take to ensure consciousness of the need to respect diversity in daily life? What actions should I take to maintain a safe and healthy living environment? What actions should I take to make sustainable choices? Based on these four practical problems, four lesson topics were developed in accordance with both the voyeur's and the critical perspectives, resulting in a total of 8 sessions. The subsequent delivery of an 8-session class on global citizenship education in home economics yielded significant improvements in the global citizenship competencies (knowledge, skills, attitudes, and willingness to act) of 37 elementary school students immediately after the sessions. The significance of this study lies in its focus on the core ideas of the revised 2022 curriculum, thereby offering directions for the development of global citizenship education within the curriculum.

• Korean Security Journal
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• no.22
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• pp.231-258
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• 2010

A study apartment house inhabitants of to, crime prevention effort is done satisfaction analysis and that deduce design plan of CPTED that can overcome safe life space embodiment and criminal fear from crime in Juminin viewpoint through atomize group's interaction by background fantast. Is positive because factor analysis wave and satisfaction index of deduce universe (Total group) 8 factor are presented more than all 0, and quite was expose by level that is worth accommodating. Satisfaction index of The secondary design group (Group1) 8 factor is positive because is presented more than all 0, and mechanical access control, mechanical surveillance is level that is worth accommodating quite, and level that is proper in remainder 6 dimension appear. Can know that 1 The secondary design group(Group2) is expose by level that satisfaction characteristic of 8 factor can be presented more than all 0 and appeared positively, and accommodate quite in all dimensions. Result that analyze Two-way ANOVA satisfaction difference of environment design of group by satisfaction of the primary and the secondary design group is high in 8 all dimensions of CPTED, and satisfaction by appeared satisfaction high in group less than natural access control, 2 years of natural surveillance, and reciprocal action effect that go with group is high satisfaction in 2 years low in The secondary design group more than the primary and the secondary design group of systematic access control and natural access control, and the primary and the secondary design group appeared high in subgroup of 2 remainders. Satisfaction difference by group by crime prevention effort satisfaction of the primary and the secondary design group is high in 8 all dimensions of CPTED, and satisfaction difference by crime prevention effort appeared satisfaction high in 'A prize' group to The secondary design group, and reciprocal action efficiency is high in 'A prize' group in The secondary design group more than the primary and the secondary design group in mechanical access control, systematic access control, natural access control, territoriality reinforcement, and satisfaction of 'Between' and 'Very' group appeared high in the primary and the secondary design group.

• Journal of Korean Home Economics Education Association
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• v.22 no.1
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• pp.1-19
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• 2010

The purpose of this study was to develop practical problem focused teaching learning process plan for housing for the later life in order to apply it to the older stage of family planning section of Technology Home Economics in a highschool. Practical problem focused method was used for the teaching learning process plans of 3-session lessons according to the ADDIE model. The global practical problem was "What should I do to plan a safe and comfortable housing for the later life?" In the development stage, 53 teaching learning materials (44 students activity materials, 2 students' and 5 teacher' reading texts, and 2 moving pictures) were developed for 3-session lessons. The planes applied to the 5 classes, 150 students, in the freshmen of B highschool during April 20th-24th, 2009. The 5 point likert questionnaire were used to evaluate the 3-session lessons about 4 contents related aspects as well as the methods and effects of the lessons besides 2 open ended questions. The overall evaluation was very positive in all 6 aspects of the lessons. Some students wanted to learn more about universal design and aging related jobs. Those results showed that the practical problem focused teaching learning process plan for housing for the later life which this study developed would be appropriate to teach the older stage of family planning section related to housing and could be adjusted to the condition of each school and regions.

• Journal of the Korea Concrete Institute
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• v.18 no.6 s.96
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• pp.721-728
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• 2006

Earthquakes are reported thai building structures have been colossal damaged, but before 1988 designed structures which were not applicate seismic design code have no seismic performance. Especially, for the apartment structures were indicated that it have no resist wall element of earthquake before 1988 designed structures. We have to evaluate for seismic performance this structures, therefore it will be retrofitted for seismic index sufficient structures. We performed seismic performance evaluation for model structures by MIDAS which is general structure analysis software. In this study, it was performed shaking table test to evaluate model structure which is reinforcement concrete and 5 floors for seismic performance index. We made specimens by similar's law and tested shaking table test. In the shaking table test it is not performed prototype model test because of space and equipment condition. So we had made scale-down model for 1/5 by similar's law. That's why it needs for the evaluation of performance. However, it is not possible to do an experiment of prototype owing to the shortage of space and the limit of an experimental instrument in the shaking table test. Then, modeling and reducing the part of prototype do the experiment. In this experiment a shaking table test is done and seismic performance of model structures is evaluated by using similitude laws for scale down specimen. As a result it is proved that non-seismic design structures need to retrofit since seismic performance shows life safe grade in 0.12g of an earthquake.