• International Journal of Vascular Biomedical Engineering
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• v.3 no.1
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• pp.1-5
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• 2005

Background: Coronary atherosclerosis artery disease is the leading cause of morbidity and mortality. Coronary artery bypass grafting (CABG) which utilizes the saphenous vein graft, has helped in alleviating the suffering of these patients. Newer techniques are being developed to improve upon the techniques. Still there is significant number of failures, leading to re-grafting or re-vascularization. Some studies have helped in identifying the high and low shear stress regions. Further studies based on their realistic models are required. Material, methods and results: we developed the realistic model of fully blocked right coronary with bypass graft placed at angle of $5^0$ with curvature similar to that of artery. Pulsatile flow of birefringent solution through this model by polarized light was visualized. The images of complete flow field in the model were recorded and analyzed. Regions of high flow disturbances which are prone to further changes are identified. Existence of recirculation in the blocked coronary may initiate new blood-tissue interactions deleterious to bypass graft. Conclusion: Our study shows that by selecting the procedure to place bypass graft at minimum angle with curvature similar to that of artery and smooth sutures may improve the life span of the graft. This study also identified that coronary blocked regions contributing by recirculation flow at the proximal and distal regions of bypass which may require further studies.

• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.166-170
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• 2006

This study was carried out to investigate the fermentation characteristics and optimum conditions for alcohol fermentation of the Korean native mulberry. The yeast strains of S. kluyveri DJ97, La parisienne (Saccharomyces cerevisiae, Netherlands) and Enoferm (Saccharomyces cerevisiae, Denmark) produced higher alcohol concentrations than other strains, and further study was therefore performed with these three species. The optimum additional water content for maximizing alcohol concentration was 250% (v/w). The alcohol concentrations were rapidly increased in the first 4 days under the optimum conditions and reached 13.8% for S. kluyveri DJ97, 14.0% for La parisienne and 14.0% for Enoferm, respectively. Residual sugar concentration was decreased steadily from the beginning of fermentation until 5 days, after which it maintained a constant level. The pH was decreased steadily in the log phase during further maturation. However, the pH underwent a slight decrease after 4 days and then was stabilized during further maturation. Methanol concentrations for the three species used were analyzed after 60 days maturation and were lower than the levels regulated by the food standard. Fusel oils such as n-propanol, iso-butanol, and iso-amyl-alcohol were produced as by-products with the highest production from Enoferm and the lowest from S. kluyveri DJ97.

• Journal of the Korean Society of Safety
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• v.39 no.1
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• pp.114-122
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• 2024

This study aimed to identify the multiple mediation effects of job satisfaction and job commitment on the relationships between job stress and workers' safety behavior in terms of compliance and participation, in which the multiple mediation effects are a hybrid of parallel and serial mediating relationships. The multiple mediation model was analyzed using the bootstrapping method through the PROCESS macro tool in SPSS. The results showed that job stress negatively affects job satisfaction, job commitment, and workers' safety behavior, and the relationship between job stress and safety behavior is mediated by both job satisfaction and job commitment. The serial mediation effects of job satisfaction and job commitment were also found to be statistically significant in the regression relationship between job stress and safety behavior. Further analysis of the compliance and participation subdimensions of safety behavior showed similar results. Specifically, the serial mediation effects of job satisfaction and job commitment on participation and compliance behavior were further supported; however, the mediation effect of job satisfaction was not significant, whereas that of job commitment did remain significant. Further research is needed to determine if the mediation effect of job satisfaction found in this study can be extended and generalized to workers in various fields and industries.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.1
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• pp.41-54
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• 2005

The purposes of this study on various headgear at the age of the Persian Achaemenes are to analyze one cultural aspect of the Achaemenes Kingdom that made a great empire about 5th century B.C. and to understand the ancient Persian culture. It is widely recognized that the Persian region was an important place for cultural exchange between the East and the West through the Silk Road and its culture affected China and Korea. Therefore, it is necessary to study ancient culture in this region for further understanding of the Korean culture. However, research activities have not been satisfactorily conducted. This study is an attempt to elevate the interest in this subject. In this study, European archeological materials covering Naqsh-e-Rostam (a tomb of Darius), Apadana stairs, Darius palace in Persepolis, and Bistun(Behistun), the relief at the age of the Achaemenes Kingdom, were collected and analyzed. From this study, the following results were obtained. For crowns at the age of the Achaemenes Kingdom, two kinds of shapes are observed; Mitra, a kind of headband, in the early period and a cylindrical one in the later period. Mitra was also worn by chiefs trusted by the king. Further, slightly different styles of cylindrical crowns were observed, which is considered that kings might wear unique crowns to symbolize new period of their reign. In addition to crowns, various styles of headgear for subjects are observed, meaning that tribes conquered by the Persian empire used their unique headgear. Further, such different styles of headgear might be a tool for social classification. Representative styles of headgear include the semicircular one worn by the Median nobles, Strophion originated from the Elam's headband, and nomadic tribes' Baschlik observed in the Median relics.

• Journal of the Korean Chemical Society
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• v.56 no.2
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• pp.201-206
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• 2012

The anticorrosive effect of 3-Hydroxyflavone (3HF) in combination with quarternary ammonium bromide and iodide salts (QAB and QAI) for aluminium corrosion in NaOH medium was studied at the temperature range of 303K-323K using weight loss study, potentiodynamic polarization study and impedance spectroscopic measurements. The results revealed that the inhibition efficiency increases with the inhibitor concentration and it further increases on the addition of quarternary ammonium bromide and iodide salts. The enhanced inhibition efficiency of the inhibitor in the presence of quarternary ammonium salts may be due to synergistic effect. The adsorption process of 3HF on the aluminium surface obeys Langmuir's adsorption isotherm. The mechanism of adsorption is further supported by Scanning Electron Microscopic study (SEM).

• Journal of Korean Society of Transportation
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• v.12 no.1
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• pp.137-149
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• 1994

The objective of study is to evaluate the effect of speed control hump on traffic operation and accidents. Three sites were investigated for the change of traffic accidents before and after the hump installation. Vehicle speeds approaching the hump were also analyzed. The study revealed that not only the number of traffic accidents but also the accident severity were significantly reduced by the installation of hump. Further, different types of traffic accidents with lower severity were observed after the hump installation. For the effect of speed reduction by hump, it was found that the speeds observed at 15m upstream of hump were in the range of 36~50 percent of approaching speeds which were not affected by (ie, without) the hump. Economic analysis of hump installation showed the benefit-cost ratio of 4.3 and 11.2 at two sites. Further analysis revealed that the benefit by the accident reduction exceeds the cost by speed reduction and installation capital if AADT is below 43,150 vehicles on two lane highways. It is recommended from the study that humps should be considered on two lane highways of high accident locations for excessive speeds to reduce traffic accidents and severity.

• Journal of the Korea Furniture Society
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• v.28 no.4
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• pp.362-370
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• 2017

To improve usability and recognition of product, the term, Affordance, started to be known in the design world by US recognitive psychologist, Donald A. Norman, has the meaning of providing, Act inducement, Act motivation, Expectancy or what environment provides, etc., thus as one of Mental Model, providing ever more importance not only to the everyday life goods but to the time like these days when products for information overflow. Particularly, this study is oriented toward providing basic study framework on Affordance-like approach in pursuing psychological approach in design for changing the limitless phenomena involved in environment and human body and further for inquiring into source of idea from abstract form hint latent in act and further from the act conducted everyday while peoples are unconscious.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.1
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• pp.23-35
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• 2008

The purposes of this study are to analyze problems in industrial classification of fisheries in Korea and to suggest future directions. Based on a thorough review of relevant literature, the study proposes a five-level scheme for classifying fisheries. The highest level should be the fisheries industry, and the next highest level ought to be fisheries. The medium level should include fishing, aquaculture, and fishery service industries. At the fourth level, fishing is to be further divided into sea fishery and inland fishery, aquaculture into sea-surface aquaculture and inland aquaculture, and fishery service industries into integrated fishery service and fishery distribution service. The lowest level is the most detailed. At this level, sea fishery is split into deep sea fishery, offshore fishery, and coastal fishery; sea-surface aquaculture consists of sea aquaculture, seed production aquaculture, and food organism aquaculture; integrated fishery service is further classified into fishery-related service and fishery information service.

• International Journal of Contents
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• v.16 no.4
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• pp.39-49
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• 2020

The goal of this research was to understand the patterns of multidimensional engagement in MOOCs. An email with an online survey link was sent to enrollees in an MOOC course. The survey included 35 questions asking about engagement, teaching presence, and learning persistence. The items were validated in the literature, revised for the MOOC setting, reviewed by four professionals in the field of educational technology, and used in the study. A heterogeneous group of 170 individuals gathered through convenience sampling participated in the study. With cluster analysis of the engagement data, three groups were identified: Cluster1, 2, and 3. Cluster 1 scored high on behavioral, emotional, and cognitive engagement. Cluster 2 scored high on behavioral aspects but low on emotional and cognitive engagement. Cluster 3 scored low on behavioral and cognitive engagement but high on emotional aspects. The study addressed cluster-specific learner characteristics and differences in perceived teaching presence and learning persistence. Design strategies pertaining to each cluster were further discussed. These strategies may guide instructors and practitioners in the design and management of MOOCs and should be further validated through future studies.

• International Journal of Advanced Culture Technology
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• v.10 no.2
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• pp.69-78
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• 2022

The purpose of this paper is to summarize the cursive script of traditional calligraphy and develop further possibilities based on the study of the painting and postscript of Ink bambooo, which was painted by wu zhen(吳鎮) during the Yuan Dynasty. The second section in this paper provides a summary of wu zhen(吳鎮)'s life, in addition to "Ink bambooo" and its painting postscript. The third and fourth sections are focused on analyzing the cursive script in the painting postscript of Ink bambooo, including the left-and-right structure, head prefix symbols, and bottom prefix symbols. The aim of this paper is the study of cursive script, and the theories and methods of the characters proposed by Dr. Cai Yonggui (from Fujian Normal University) and Dr. Liu Dongqin (from Southeast University) will be used to provide a summary. The presentation of the research results of this paper is designed to develop further possibilities for this type of traditional calligraphy.