• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.1
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• pp.15-19
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• 2014

As the space of the wind power generator stator end is limited, it is difficult for us to place the inner evaporative cooling system in it. We use the non-overlapping concentrated windings scheme to solve the placing and cooling problem. The characteristic of a 5MW direct-driven permanent magnet generator with non-overlapping concentrated windings were analyzed under no-load, rating-load and short-circuit by (Finite Element Method) FEM for verification of design. We studied the connection methods of the stator windings and designed the end connection member. The heat dissipation of the stator end was simulated by FEM, the result showed that the end cooling could satisfy the wind generator operation needs. These results show that the direct-driven permanent magnet wind power generators with non-overlapping concentrated windings and inner evaporative cooling system can solve the cooling problem of wind power generator, and obtain good performance at the same time.

• Journal of the Korean Ceramic Society
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• v.45 no.12
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• pp.807-814
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• 2008

The Cu-Ni-YSZ cermet anodes for direct use of methane in solid oxide fuel cells have been fabricated by electroplating Cu into the porous Ni-YSZ cermet anode. The uniform distribution of Cu in the Ni-YSZ anode could be obtained via pulse electroplating in the aqueous solution mixture of $CuSO_4{\cdot}5H_{2}O$ and ${H_2}{SO_4}$ for 30 min with 0.05 A of average applied current. The power density ($0.17\;Wcm^{-2}$) of a single cell with a Cu-Ni-YSZ anode was shown to be slightly lower in methane at $700^{\circ}C$, compared with the power density ($0.28\;Wcm^{-2}$) of a single cell with a Ni-YSZ anode. However, the performance of the Ni-YSZ anode-supported single cell was abruptly degraded over 21 h because of carbon deposition, whereas the Cu-Ni-YSZ anode-supported single cell showed the enhanced durability upto 52 h.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.05a
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• pp.78-81
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• 1995

In the present study, the spray column type of direct contact heat exchangers are studied experimentally to analyze heat transfer characteristics for solar energy utilization. These experiments are carried out in the line of solar heating system, major results are as follows ; 1) the flow and aspect of working fluid drop for maxium heat transfer 2) efficiency and volumetric heat transfer coefficient of D. C. H. X. with a heavier working fluid are higher than those of D. C. H. X. with a lighter working fluid

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.3
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• pp.159-166
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• 2023

This study analyzed what consumer characteristics affect the experience of using overseas direct purchase at a time when the overseas direct purchase market is rapidly increasing and consumers' interest in overseas direct purchase is increasing accordingly. For the study, personal data from the 2022 Korea Media Panel Survey were used, and data from 6,734 people who responded "yes" or "no" to whether or not to use overseas direct purchase among 9,941 total respondents were used for analysis. In addition, three variables (demographic, media utilization status, values and lifestyle) were selected among the items of the Korea Media Panel Survey. First, general characteristics were analyzed fo 6,734 people, then, Chi-square test and t-test were performed for comparative analysis between each variable according to the use of overseas direct purchase. Finally, logistic regression analysis was performed to identify the factors affecting overseas direct purchase. As a result of the analysis, 4 out of 5 demographic variables, 2 out of 3 media utilization variables, and 3 out of 7 values and lifestyle variables were derived as decisive factors for using overseas direct purchase. These results can be used to establish marketing strategies that can increase the use of consumers through domestic shopping malls, such as providing differentiated services for the sale of overseas direct shopping products on domestic shopping sites.

• Journal of Preventive Medicine and Public Health
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• v.18 no.1
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• pp.13-24
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• 1985

This study seeks to provide a framework for understanding differential access to medical care. The framework is provided by Anderson Model, a model of health services utilization which suggests a sequence of predisposing, enabling, illness-morbidity characteristics that determine the number of times people will visit a physician. The framework in this study is composed of two models, one is for Adults and the other is for Non-Adults. Models are operationalized using stepwise multiple regression analysis and path analysis. The data come from a national health survey conducted in 1983. The findings of the analysis can be summarized as follows : First, the causal models used in this study are able to explain only a small amount of the variance in medical care utilization(Adjusted $R^2$ is .144 in the Model for Adults and .243 in that for Non-Adults). This finding suggests that we reconsider the utility of such existing model using the predisposing, enabling, and illness-morbidity characteristics in light of their poor correspondence with these data. Second, while small amount of the valiance in medical care utilization is explained, most of the explained variance is due to the illness-morbidity characteristics. The path coefficients of study variables except illness-morbidity variables show these characteristics to be substantially unrelated to medical care utilization, and the indirect effects of the predisposing and edabling characteristics on medical care utilization are also negligible. This casts doubt on the importance of the predisposing and enabling characteristics in explaining medical care utilization. Third, among the predisposing and enabling characteristics, Medical Security variable is the only one having significant direct effect on medical care utilization in both models for Adults and for Non-Adults. Fourth, the amount of the variance explained in the Model for Non-Adults is more than in the Model for Adults. This suggests that medical care utilization of adults is more influenced by behavioral factors than that of children.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.1
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• pp.96-104
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• 2013

Study of human-robot Interaction gets more and more attention to expand the robot application for tasks difficult by robot alone. Developed countries are preparing for a new market by introducing the concept of 'Co-Robot' model of human-robot Interaction. Our research of direct teaching is a way to instruct robot's trajectory by human's handling of its end device. This method is more intuitive than other existing methods. The benefit of this approach includes easy and fast teaching even by non-professional workers. And it can enhance utilization of robots in small and medium-sized enterprises for small quantity batch production. In this study, we developed the algorithms for creating accurate trajectory from repeated inaccurate direct teaching and GUI for the direct teaching. We also propose the basic framework for direct teaching.

• Geomechanics and Engineering
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• v.37 no.6
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• pp.615-627
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• 2024

Direct simple shear test is an effective method to measure strength and deformation properties of soil. However, existing direct simple shear apparatus have some shortcomings. The paper has developed a novel dual stress/strain-controlled direct simple shear apparatus. The novel apparatus has the following advantages: A rectangular specimen is used that effectively avoid common issues associated with conventional cylindrical specimens, such as specimen tilting. The utilization of deformation control rods ensures a uniform shear deformation of the specimen. Vertically integrated force transmission structure is improved that avoids issues arising from changes in pivot points due to lever tilting. Incorporating this novel direct simple shear apparatus, shear strength and shear creep tests of clay were performed. Shear strength parameters and shear creep behaviors are analyzed. The results of these experiments show that the novel apparatus can measure accurately the shear rheological properties of soil. This study provides strong guidance for studying the mechanical properties of soil in engineering practice.

• ALGAE
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• v.25 no.4
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• pp.155-171
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• 2010

The underlying physiology of algal antioxidant compounds is reviewed in the context of seaweed biology and utilization. The application of seaweed antioxidants in foods, food supplements, nutraceuticals and medicine is considered from the perspective of benefits to human health. We advocate that direct consumption of seaweed products for their antioxidant composition alone provides a useful alternative to non-natural substances, while simultaneously providing worthwhile nutritional benefits. Economic utilization of seaweeds for their antioxidant properties remains in its infancy. This review provides examples ranging from laboratory studies through to clinical trials where antioxidants derived from seaweeds may provide major health benefits that warrant subsequent investigative studies and possible utilization.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.821-824
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• 2009

LFG-MGT CHP system development project with $CO_2$ enrichment in greenhouses was introduced. LFG is produced from the anaerobic digestion of landfilled waste and it has been utilized for power/heat generation since it contains around 50% of $CH_4$. Utilization of LFG from small scale landfill is also needed as well as large scale landfill. However, due to economy of scale, it is very difficult to develop business model. In this context, combining CHP system with greenhouses is considered as feasible option for LFG utilization. LFG-MGT CHP system with $CO_2$ fixation in greenhouses has been derived as an active greenhouse gas reduction strategy, The focus of the system is beyond carbon neutral LFG utilization to neutral carbon absorption. The system is feasible in terms of direct and indirect $CO_2$ emission reduction with more economical way.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.79-85
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• 1983

The greenhouse bulk curing and drying system utilization of the direct solar energy was tested to evaluate that how much fuel could be saved for curing flue-cured tobacco at the Dae Gu Experiment Station (North latitude : $35^{\circ}$49'), in 1979-1982. The air temperature and total radiation were 19.0 to 38.5$^{\circ}C$ and 1311.0 to 1412.7 cal/$\textrm{cm}^2$/day during the 4 replicated curing test, respectively. The greenhouse bulk curing and drying system was able to cut fuel consumption by 32% compared with the conventional bulk curing barn. We could obtain almost same utilization efficiency of solar energy in 1982 compare with normal year, mainly increasing the heat receiving area.