• Advances in Energy Research
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• v.7 no.2
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• pp.85-100
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• 2020

Distributed energy resources (DERs) are essential for coping with growing multiple energy demands. A microgrid (MG) is a small-scale version of the power system which makes possible the integration of DERs as well as achieving maximum demand-side management utilization. Hence, this study focuses on the analysis of optimal power dispatch considering economic aspects in a multi-carrier microgrid (MCMG) with price-responsive loads. This paper proposes a novel time-based demand-side management in order to reshape the load curve, as well as preventing the excessive use of energy in peak hours. In conventional studies, energy consumption is optimized from the perspective of each infrastructure user without considering the interactions. Here, the interaction of energy system infrastructures is considered in the presence of energy storage systems (ESSs), small-scale energy resources (SSERs), and responsive loads. Simulations are performed using GAMS (General Algebraic modeling system) to model MCMG, which are connected to the electricity, natural gas, and district heat networks for supplying multiple energy demands. Results show that the simultaneous operation of various energy carriers, as well as utilization of price-responsive loads, lead to better MCMG performance and decrease operating costs for smart distribution grids. This model is examined on a typical MCMG, and the effectiveness of the proposed model is proven.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.1
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• pp.170-175
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• 2022

Reactive failure management techniques are required to mitigate the impact of errors in high performance computing. Checkpoint is the standard recovery technique for coping with errors. An application employing checkpoints periodically saves its state, so that when an error occurs while some task is executing, the application is rolled back to its last checkpointed task and resumes execution from that task onward. In this paper, assuming the time-to-errors are independent each other and generally distributed, we analyze the checkpointing model with instantaneous error detection. The conventional assumption that two or more errors do not take place between two consecutive checkpoints is removed. Given the checkpointing time, down-time, and recovery time, we derive the reliability of the checkpointing model. When the time-to-error follows an exponential distribution, we obtain the optimal checkpointing interval to achieve the maximum reliability.

• The Journal of Economics, Marketing and Management
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• v.11 no.6
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• pp.35-41
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• 2023

Purpose: This study aims to determine the marketability of the heritage sites in Region III, Philippines. More specifically, it will obtain information on the: (a) profile of the heritage sites in Central Luzon; (b) dimensional issues of their marketability along social, environmental, and economic lines; (c) quality of services in terms of tangibility, responsiveness, empathy, assurance, and reliability; and (d) its business model canvas. Research design, data, and methodology: This will utilize a descriptive survey of the heritage sites in Central Luzon, namely: Aurora, Nueva Ecija, Bulacan, Pampanga, Tarlac, Zambales, and Bataan. There will be 60 respondents, including 5 facilitators, 24 residents, and 31 tourists. The results will be statistically measured through the measures of central tendencies, dispersion, and the test of significance. Result and conclusion: This study will comprehensively examine the local tourism sector, benefiting various stakeholders. It serves as a valuable resource for tourists by providing insights into destination marketing strategies and enhancing heritage tourism experiences. Administrators benefit from coping strategy evaluations, aiding in the formulation of effective strategies aligned with industry goals. Tourism businesses align with industry objectives and the study streamlines ordinances for site protection for local government units. Additionally, the community gains empowerment through insights into employable activities and potential businesses, influencing assessments of the justification for local preservation ordinances.

• Korean Journal of Social Welfare
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• v.65 no.4
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• pp.367-393
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• 2013

Quality of life(QoL) of older cancer patients have not gained enough attention from researchers even when cancer is the number one cause of death of Korean elderly. Therefore, this study aims at understanding the QoL of older cancer patients and factors related to it, applying Taylor(2012)'s Stress-Coping Process model, and by comparing with older chronic disease patients and middle-aged cancer patients. Results indicated that physical health QoL of older cancer patients was the worst and their mental health QoL was similar with middle aged cancer patients. Multi-group analysis of Structural Equation Modeling indicated that the relation between QoL and the stress coping resources was not statistically different from older cancer patients and older chronic disease group, as well older cancer patients and middle-aged cancer patients. Implications of results to improve the QoL of older cancer patients are discussed.

• Science of Emotion and Sensibility
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• v.23 no.3
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• pp.3-10
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• 2020

This study is aimed at investigating drivers' reactions to yellow signal dilemma situations as a result of the existing signal system, and developing a new signal system. A driver-centered coping model was developed through bio-signal analysis. The driver's physiological response in the existing signal system was observed, and the signal system was developed by applying intersection road driving conditions using a car graphic simulator. Participants were classified into a control group (existing signal system) and an experimental group for a new yellow signal system (new signal system). Based on the results, the emergence of parasympathetic nerves was higher in the experimental group than in the control group, where a statistically significant difference was observed (p < 0.05). The newly developed signal system appeared to cause tension among drivers; however, the sympathetic to parasympathetic nerve ratio was 6: 4, which could be interpreted as an ideal balance. We conclude that drivers can drive more stably if the coping signal system developed in this study is applied to the traffic system.

• Health Policy and Management
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• v.24 no.1
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• pp.71-84
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• 2014

Background: Informal care is increasingly recognized as placing a significant burden on the lives of family caregivers. The purpose of this study is to investigate factors related to family caregivers' burden with the community-dwelling disabled elderly under the long-term care insurance system, using the Stress Process Model developed by Pearlin (1990). Methods: Total 1,233 family caregivers with the disabled elderly, using the long-term care services in their home from May to June 2009, completed questionnaires finally. The questionnaire of this study consists of a total of 32 questions, including 11 questions related to background and context, 17 questions related to objective stressors, and 4 questions related to coping resourses. Family caregivers' burden is measured by the Korean Revised Caregiving Appraisal Scale (K-RCAS, Cronbach's alpha=0.86). To investigate factors related to family caregivers' burden, multiple regression analysis was conducted. Results: The average score of caregivers' burden was 22.0 (${\pm}6.12$). In multiple regression analysis, there were statistically significant factors affecting on the family caregivers' burden, that are related to background and context (region, living status, education level, relationship with beneficiary), objective stressors (duration of caregiving), coping resourses (caregiver's health status). Conclusion: This study found that family caregivers experience a considerable burden. The findings suggest that policies must be taken to relieve family caregivers of their duties temporarily, and to support them with counselling and education.

• The Journal of the Korea Contents Association
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• v.16 no.7
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• pp.552-565
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• 2016

This study aimed to examine the association between material hardship and alcohol use among low-income households in Korea, with particular attention to whether the association was mediated by family conflict and self-esteem. Using a nationally representative sample of 960 low-income households, this study conducted a path analysis to test a structural model liking material hardship to alcohol use through family conflict and self-esteem. The significance of indirect paths was tested by a Sobel test. This study found that experiencing material hardship was directly associated with low levels of coping skills for family conflict and low levels of self-esteem, but not with alcohol use. However, material hardship was indirectly associated with alcohol use through low levels of coping skills for family conflict as well as low levels of self-esteem. The findings of this study suggest that experiencing material hardship among low-income households would be a socio-structural stressor for alcohol use, particularly in that it increases secondary role and intra-psychic strains. Implications to address material hardship and alcohol use among low-income households were discussed.

• The Journal of Advanced Prosthodontics
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• v.4 no.3
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• pp.162-169
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• 2012

PURPOSE. Fracture of the veneering material of zirconia restorations frequently occurs in clinical situations. The purpose of this in vitro study was to compare the fracture strengths of zirconia crowns veneered with various ceramic materials by various techniques. MATERIALS AND METHODS. A 1.2 mm, $360^{\circ}$ chamfer preparation and occlusal reduction of 2 mm were performed on a first mandibular molar, and 45 model dies were fabricated in a titanium alloy by CAD/CAM system. Forty-five zirconia copings were fabricated and divided into three groups. In the first group (LT) zirconia copings were veneered with feldspathic porcelain by the layering technique. In the second group (HT) the glass ceramic was heat-pressed on the zirconia coping, and for the third group (ST) a CAD/CAM-fabricated high-strength anatomically shaped veneering cap was sintered onto the zirconia coping. All crowns were cemented onto their titanium dies with Rely $X^{TM}$ Unicem (3M ESPE) and loaded with a universal testing machine (Instron 5583) until failure. The mean fracture values were compared by an one-way ANOVA and a multiple comparison post-hoc test (${\alpha}$= 0.05). Scanning electron microscope was used to investigate the fractured interface. RESULTS. Mean fracture load and standard deviation was $4263.8{\pm}1110.8$ N for Group LT, $5070.8{\pm}1016.4$ for Group HT and $6242.0{\pm}1759.5$ N for Group ST. The values of Group ST were significantly higher than those of the other groups. CONCLUSION. Zirconia crowns veneered with CAD/CAM generated glass ceramics by the sintering technique are superior to those veneered with feldspathic porcelain by the layering technique or veneered with glass ceramics by the heat-pressing technique in terms of fracture strength.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.1
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• pp.81-92
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• 2014

It is so hard to obtain optimal anterior esthetics in the implant prosthesis. This is not only because of hard and soft tissue problem such as alveolar bone resorption and interdental papilla loss but also because of prosthetic limitation related to marginal exposure of metal abutment and metal ceramics and low transillumination. In this case, guided soft tissue healing is obtained using a long term provisional restoration with soft and hard tissue augmentation or immediate implantation. Then, this healed tissue is transferred to final master model using a customized impression coping and the implant is restored with a customized zirconia abutment and a all ceramics. This case presents satisfying result esthetically and functionally.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.1-17
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• 2023

Purpose. The purpose of this study was to examine the correlation between the finish line designs and the marginal adaptation of nonprecious metal alloy coping produced by different digital manufacturing methods. Materials and methods. Nonprecious metal alloy copings were made respectively from each master model with three different methods; SLS, milling and casting by computer aided design and computer aided manufacturing (CAD-CAM). Twelve copings were made by each method resulting in 72 copings in total. The measurement was conducted at 40 determined reference points along the circumferential margin with the confocal laser scanning microscope at magnification ×150. Results. Mean values of marginal gap of laser sintered copings were 11.8 ± 7.4 ㎛ for deep chamfer margin and 6.3 ± 3.5 ㎛ for rounded shoulder margin and the difference between them was statistically significant (P < .0001). Mean values of marginal gap of casted copings were 18.8 ± 20.2 ㎛ for deep chamfer margin and 33 ± 20.5 ㎛ for rounded shoulder margin and the difference between them was significant (P = .0004). Conclusion. Within the limitation of this study, the following conclusions were drawn. 1. The variation of finish line design influences the marginal adaptation of laser sintered metal coping and casted metal coping. 2. Laser sintered copings with rounded shoulder margin had better marginal fit than deep chamfer margin. 3. Casted copings with deep chamfer margin had better marginal fit than rounded shoulder margin. 4. According to the manufacturing method, SLS system showed the best marginal fit among three different methods. Casting and milling method followed that in order.