• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.174-178
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• 1999

This paper describes an investigation on bearing failure due to spragging that has been continuously occurred in turbine hearings. The spragging is defined as the damage found on the leading edge of unloaded pads in the tilting pad journal bearing, In general, the damage mechanism by spragging is classified into fatifgue failure, The principle cause of spragging could be thought as the self-excited vibration by the absence of a stable static equilibrium position of upper pads with no preload. Because of serious consequences of system breakdowns due to bearing failures, determination ar the causes of failure and effective method for countermeasures are very important. This paper describes both the causes of spragging and countermeasures for prevention of such failure, which are taken place in the electric power plants.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.10 s.115
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• pp.1050-1056
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• 2006

In this paper, a new method for the stability analysis of a pipe conveying fluid which pulsates periodically is presented. The finite element model is formulated liking into consideration of the effects of the fluid pulsating in a pipe. The damping and stiffness matrices in the finite element equation vary with time due to pulsating fluid. Coupled effects of several harmonic components in the velocity of fluid to a pipe is discussed. A new unstable region appears which will not appear in the stability analysis of single pulsating frequency. A method to directly estimate the forced response of pipe is also discussed. The results presented in this paper are verified by the time domain analysis.

• Macromolecular Research
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• v.12 no.4
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• pp.336-341
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• 2004

A new type of cross-linked methylaluminoxane (MAO)-supported cocatalyst has been prepared by the reaction of a soluble MAO and a cross-liking agent such as an aromatic diamine compound. The cross-linked MAO-supported cocatalyst was used for the polymerization of ethylene in the presence of bis(n-butylcyclopentadienyl) zirconium dichloride, (n-BuCp)$_2$ZrCl$_2$. The catalyst activity of (n-BuCp)$_2$ZrCl$_2$ cocatalyzed with the new supported cocatalyst was higher than that of the commercial silica-supported MAO (SMAO) cocatalyst. The molecular weight and the bulk density of the polyethylene produced by using the new supported cocatalyst were slightly higher than those of polyethylene synthesized using commercial SMAO. The resulting polyethylene particles possess spherical morphologies with very few fine particles.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.2 no.3
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• pp.24-35
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• 2003

With the arrival of 3rd generation cellular networks it is expected that a lot of new cellular services will be available to the mobile users like video calling, location based services etc. Similarly MBMS is one such service which is targeted for 3G mobile users for viewing talk shows, live sport events etc. One shall view this service like a small portable T.V being carried by the mobile user. The user watches the programs of his liking by joining if he wishes. In this paper we focus on the possible UTRAN architectures to provide MBMS service within UMIS networks. The paper primarily focuses on the requirement aspect, notification aspect and the mobility aspect. The paper lists many options for notifications and elaborates on them in terms of pros and cons. In the end the paper conclude with an UTRAN architecture for MBMS service which meets the requirements of this service as well as makes minimum changes to the existing UTRAN architecture while attempting to save terminal power for this service.

• Plant Resources
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• v.8 no.3
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• pp.230-234
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• 2005

This study was conducted to determine feasibility of utilization of Angelica acutiloba. Especially, the quality characteristics of bread prepared with the addition of Angelica acutiloba powder were investigated. Sensory evaluation and spoilage test were conducted for preparation of functional breads which added with ground plant matters (leaves and stems) from Angelica acutiloba. The result showed that the functional breads had high score of overall liking as well as low spoilage rate when added with 0.5 to 1.0% ground plant matters of Angelica acutiloba. Consumer acceptability evaluation showed a significant preference when added 0.5 to 1.0% ground leaves and stems of Angelica acutiloba into breads. Functional breads which added powder of Angelica acutiloba inhibited the growth of fungi. The more addition of Angelica acutiloba powder, the higher the degrees of this inhibited. These results suggested that the shelf-lives of the breads were extended by the addition of Angelica acutiloba powder. Further studies were required for improvement of functionality and diversity of bread products using medicinal plant materials as an additive.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.6
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• pp.1033-1041
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• 2010

This study investigates the combined effect of clothing interest and fashion innovativeness on dimensions of scent quality (pleasantness, intensity, familiarity, and congruency) to understand which dimensions of scent quality have significant positive effects on the appeal of scented apparel products. The survey data were statistically analyzed. A structural equation modeling using LISREL was conducted to test the model. Results indicate that clothing interest has a significant impact on scent quality attitude. Positive evaluations of the product were most strongly influenced by the pleasantness quality of the scent. Intensity and familiarity were factors that affected the approach of consumer responses toward scented products. Congruency was not a significant scent quality in generating positive responses for apparel products among consumers.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.608-616
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• 2008

This paper describes a study of the conditions and reasons that elementary school children avoid the namul provided in school meals. This study was conducted with a sample of 751 fifth-grade elementary school children and 49 nutritionists working in elementary schools. Nutritionists felt the need to develop new recipes, and were taking note of leftovers in an effort to increase namul consumption. 47% of the students reported liking namul, and the majority of students who disliked namul reported that its taste was the reason that they disliked it. Nutritionists believed that the students avoided namul due to a lack in familiarity, as well as taste. However, students answered that they disliked namul not only due to its taste, but also due to its texture.

• Journal of Fashion Business
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• v.9 no.6
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• pp.1-11
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• 2005

The purpose of this study were to examine how people categorize obese individuals and if they have stereotyping about obese individuals. Twenty-five female volunteer subjects participated in this study. Subjects were undergraduate students in Textiles and Clothing courses at a midwestern university, US. Subjects were asked to give their one-word responses to four statements or questions regarding their impressions of six stimuli. The six stimuli consisted of magazine photographs of women; the magazines were general interest and fashion publications. Subjects then recorded their answers in the boxes for each of the six pictures. As the results, the relevant question as to whether or not more negative attributes would be assigned to the obese model's photographs was confirmed for the Description of Model variable, but not for the Personality of Model or for the Liking the Model variables. There was significant difference in means between the positive and negative descriptions of the Description of Model variable in the direction of negativity toward the obese group seems to confirm that, not only do people categorize others based on appearance, but there was a tendency to favor the average-size group and to view as negative the obese group.

• Journal of Information Processing Systems
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• v.10 no.2
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• pp.271-282
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• 2014

The advancement of knowledge society has enabled the social network community (SNC) to be perceived as another space for learning where individuals produce, share, and apply content in self-directed ways. The content generated within social networks provides information of value for the participants in real time. Thus, this study proposes the social network community activity-based content model (SoACo Model), which takes SNC-based activities and embodies them within learning objects. The SoACo Model consists of content objects, aggregation levels, and information models. Content objects are composed of relationship-building elements, including real-time, changeable activities such as making friends, and participation-activity elements such as "Liking" specific content. Aggregation levels apply one of three granularity levels considering the reusability of elements: activity assets, real-time, changeable learning objects, and content. The SoACo Model is meaningful because it transforms SNC-based activities into learning objects for learning and teaching activities and applies to learning management systems since they organize activities -- such as tweets from Twitter -- depending on the teacher's intention.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.4
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• pp.73-85
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• 1991

Rhododendron mucronulatum for. albiflorum, native species is a shrub that has white flowers on May to June, and rare species endangered by people's rash digging or cutting. But its physiological ecological characteristics and propagation method are not being known at all. Therefore, this study was executed to utilize this species as the planting material for landscaping by analysing its habitat environment and growth form, and also experimenting its seed and vegetative propagation, and it field culture and utilization. The results are as follows; 1. The elevation, gradient and direction of this species were 295-1,350m, 10-36$^{\circ}$, northwest respectively. It was found that the species is shade-liking plant that grows under forest cover of average 51.33%. 2. The soil pH and water content of its habitat were 5.4, 25.41% respectively. The organic matter content was 6.29% that was higher than 3.2%, the average organic matter content of forest soil in Korea. 3. Representative plant community within which this species was living was Quercus mongolica community, and its main neighboring species were Lindea obtusiloba, Fraxinus sieboldiana, Rhus trichocarpa, Rhododendron Schlippenbachii, Rododendron mucronulatum. 4. The leaf length and width of this species were 39.18mm, 12.60mm respectively. This result showed that generally its leaf size was larger than that of R. micranthum, R. yedoense var. poukhanense and R. mucronulatum var. ciliatum and smaller than that of R. mucronulatum and R. schlippenbachii. 5. The whole size of its pollen was, as 59${\times}$61$\mu\textrm{m}$, the largest of plants of Rhododendron family including R. mucronulatum and R. mucronulatum var. ciliatum. 6. The result of seed germination experiment at intervals of 5$^{\circ}C$ from 15$^{\circ}C$ to 30$^{\circ}C$ presented the highest germination rate of 94.7% at 20$^{\circ}C$ numerically, but high percent germination at all temperature levels without significant difference. And the seed of this plant proved to be sun-liking seed at requiring dormancy in germination. 7. Through seed germination experiment by treatment of growth regulators such as GA. Thiourea and Kinetin under dark condition, it was found that the effect of GA treatment on germination increase and acceleration was the highest. 8. In greenwood cutting, rooted rate by treatment of various concentration of IBA and NAA on clay and vermiculite bed was not wholly high, but 100ppm plots of both IBA and NAA of clay bed showed relatively good rooted rate. 9. As result of field culture experiment for finding out optimum growth temperature and light intensity, growth conditions such as height, number of leaves, fresh weight and chlorophyll contents were the best at night/day temperature of 20/25$^{\circ}C$ and under 1/2sun. Also, the photosynthetic rate was the highest at 25$^{\circ}C$. Accordingly, it was found that optimum temperature and light intensity for growth of this plant are 25$^{\circ}C$ (day temperature), 50% of natural light respectively.