• Journal of Mechanical Science and Technology
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• v.19 no.6
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• pp.1229-1242
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• 2005

When natural rubber is used for a long period of time, it becomes aged; it usually becomes hardened and loses its damping capability. This aging process affects not only the material property but also the (fatigue) life of natural rubber. In this paper the aging effects on the material property and the fatigue life were experimentally investigated. In addition, several fatigue life prediction equations for natural rubber were proposed. In order to investigate the aging effects on the material property, the load-stretch ratio curves were plotted from the results of the tensile test, the compression test and the simple shear test for virgin and heat-aged rubber specimens. Rubber specimens were heat-aged in an oven at a temperature ranging from $50^{\circ}C$ to $90^{\circ}C$ for a period ranging from 2 days to 16 days. In order to investigate the aging effects on the fatigue life, fatigue tests were conducted for differently heat-aged hourglass-shaped and simple shear specimens. Moreover, finite element simulations were conducted for the specimens to calculate physical quantities occurring in the specimens such as the maximum value of the effective stress, the strain energy density, the first invariant of the Cauchy-Green deformation tensor and the maximum principal nominal strain. Then, four fatigue life prediction equations based on one of the physical quantities could be obtained by fitting the equations to the test data. Finally, the fatigue life of a rubber bush used in an automobile was predicted by using the prediction equations, and it was compared with the test data of the bush to evaluate the reliability of those equations.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.32-32
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• 2011

Cold Pad batch(CPB)처리에 의한 직물 전처리 공정은 특히 저온처리방식이라 에너지 소모가 적으며, 발생되는 대기오염 및 용수사용량이 연속식 방법에 비해 약 30%이상 절감되는 경제적 친환경적인 기술로 특히 정련과 표백을 동시에 수행할 수 있다. CPB 전처리는 호발, 정련, 표백을 포함하는 공정으로 일욕으로 처리시 패딩, 수세, 와인딩 공정을 단축시키기 때문에 약품 소비량 감소와 에너지 사용 절감 효과가 있어 전 세계적으로 확산되고 있는 Green Technology이다. 본 연구에서는 CPB용 다기능성 일욕형 조제에 개발하기 위해 전처리시 정련, 표백성에 대한 연구를 진행하였다. 시료는 NP/C 교직물을 사용하였고, CPB 처리액은 원료 및 첨가용제를 여러 비율로 조합하여 조제를 formulation 하였다. 이를 사용하여 패딩, 배칭, 수세 및 건조하여 전처리를 하였다. 표백된 정도를 파악하기 위해 Macbeth Color Eye-3100을 사용하여 백도(whiteness(CIE))를 5회 평균값을 구하여 측정 하였다. 정련된 정도를 비교하기 위해 C.I.Reactive Red 238의 2g/l 용액을 사용하여 wicking test를 하였다. 1분간 흡수높이를 측정하여 정련성을 확인하였다. 각각의 첨가용제를 비교한 결과 isopropyl alcohol을 첨가 시 hexylene glycol, butyl diglycol를 첨가한 경우에 비해 높은 흡수높이를 나타내었다. isopropyl alcohol의 농도별 정련성을 알아보기 위해 0%, 5%, 10%의 농도로 처리하였다. 그 결과 isopropyl alcohol 첨가량이 많을수록 정련성이 증가하였다. 다기능성 일욕조제의 문제점인 알칼리 안정성 부족을 보완하기 위해 polyoxyethlylene tridecyl ether derivatieves(LAP300)의 인화물을 첨가하였다. LAP300의 첨가량이 증가할수록 정련성이 증가하는 경향을 나타내었다. 알칼리 안정성 및 타 성능(정련성, 백도, 킬레이트 성)을 종합적으로 평가하여 향후, CPB용 다기능성 일욕형 조제의 개발에 대한 연구를 진행할 계획이다.

• Journal of Energy Engineering
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• v.8 no.4
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• pp.605-611
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• 1999

Conventional methods for assessing remaining life of critical high temperature components in fossil power plants rely on nondestructive inspection practices and accompanying life analysis based on fracture mechanics By using these conventional methods. It has been difficult to perform uninterrupted in-service inspection for life prediction. Thus, efforts have been made for developing on-line remaining life monitoring systems employing information on the shape of structures, operating variables and material properties. In thus study, a software for on-line life monitoring system which performs real-time life evaluation of a high temperature system headers was developed. The software is capable of evaluating creep and fatigue life usage from the real-time stress data calculated by using temperatures/stress transfer Green functions derived in advance for the specific headers. The major benefits of the developed software life in determining future operating schedule, inspection interval, and replacement plan by monitoring real-time life usage based on prior operating history.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.77-80
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• 2011

A new bi-color mini gerbera (Gerbera hybrida Hort.) 'Sun Cap' was developed from a cross of '99-ga-2' and '99-na-3-1' followed by seedling and line selections at the Flower Research Institute, Gyeongnam Agricultural Research and Extension Services (ARES) in 2007. Characteristic tests were conducted three times from 2004 to 2007. 'Sun Cap' has single type in good harmony with bi-color (Red/Yellow, RHS 45-B/9-A) ray floret and green center. It has good stable flower shape and strong peduncle. Its vase life was 13.5 days. The average yield of 'Sun Cap' was 102.6 flowers per plant a year in greenhouse. Yield trials were carried out from 2004 to 2007. This cultivar was registered for commercialization in 2009. 'Sun Cap' would be cultured under greenhouse condition in Korea.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.585-590
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• 2000

The studies were carried out to know shade tolerance of the plants for the urban forest aromatic bath. The one to two year old potted seedlings were grown under the one of the five light conditions such as 100%, 50%, 30%, 10% and 2% of the full sun light intensities. Pinus densiflora S. et Z., P. sylvestriformis (Takenouchi) Chien., Thymus quinquecastatus Celak, Lonicera japonica Thunb, and Zingiber officinale Roscoe showed decreasing tendencies in height and root collar diameter growth, and dry mass production as the light intensity decreases. Exceptionally Thuja koraiensis Nakai showed the best growth in the 50% of full sun light intensity. Athyrium yokoscense (Fr. et Sab.) H. Christ showed better growth in the relative light intensity of 10 to 15% than in the in the relative light intensity of 25 to 30% in the bath green house.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.18 no.3
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• pp.383-391
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• 2011

Purpose: This study was done to develop a web-based education program on appropriate antibiotic use and test the effects of the program on knowledge and attitudes towards antibiotic use in Korean adolescents. Methods: The web-based education program was developed through an extensive literature review and professional advisory meetings including technical assistance from a web-based education programmer and content experts. A convenience sample of 851 students from middle and high schools participated in the assessment of effects of the program. Knowledge and attitudes of the students towards antibiotic use and satisfaction with the web-based education program were measured. Descriptive statistics and paired t-test were used to analyze the data. Results: There were significant improvements in knowledge and attitudes towards antibiotic use following self-learning via the web-based education program in both middle and high school students. High school students demonstrated higher scores in knowledge and attitudes than middle school students. Conclusion: The results of this study indicate that this web-based education program on appropriate antibiotic use is a convenient and effective medium for self-learning in adolescents. Therefore the web-based program should be put into wide use as an effective and convenient teaching method for health education in secondary schools.

• FLOWER RESEARCH JOURNAL
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• v.18 no.4
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• pp.295-298
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• 2010

A new spray chrysanthemum(Dendranthema grandiflorum) cultivar, 'Biz' was developed from a cross between 'S03-117' and 'Angaesoguk' by selection of seedlings and lines at the Flower Research Institute, Gyeongnam Agricultural Research and Extension Services(ARES) from 2003 to 2008. Its characteristics were investigated three times from 2006 to 2008 under condition of forcing culture in spring and retarding culture in autumn. The natural flowering time of 'Biz' was October 26th, and year-round production was possible by day length treatment. This cultivar was white in color, single in flower type for the spray type cut flower. Its capitulum was 3.0 cm in diameter, and had 15.6 head per stem in autumn. Its ray floret was green central zone. The days to flowering under the short day treatment is about 42 days in spring season, and 'Biz' showed the vase life of 24.1 days in autumn. This cultivar was registered for a commercialization in 2008.

• FLOWER RESEARCH JOURNAL
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• v.18 no.3
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• pp.211-215
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• 2010

A new spray chrysanthemum(Dendranthema grandiflorum) cultivar 'Magic' was developed from a cross combination between 'Artist Pink' and 'SP0347' by selection of seedlings and lines at the Flower Research Institute, Gyeongnam Agricultural Research and Extension Services(ARES) from 2003 to 2007. Its characteristics were investigated three times from 2005 to 2007 under condition of forcing culture in spring and retarding culture in autumn. The natural flowering time of 'Magic' was October 26th, and year-round production was possible by day length treatment. Its capitulum was 6.1 cm in diameter, and had 31.9 ray florets and 11.7 head per stem in autumn. Its ray floret was white-purple with yellow green central zone. Days to flower of 'Magic' was about 43 days in spring, and 'Magic' showed the vase life of 20.6 days in autumn. This cultivar was registered for a commercialization in 2007.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.1-7
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• 2011

This study was carried out to establish a production system of cut flowers and bulbs of oriental hybrid lilies in highland in summer. In study, effect of cultivation type and shading was examined. The cultivation types used in the bulb production experiments were greenhouses with no cover, greenhouses with net screen (net screen house), and greenhouses with EVA roof cover and net screen sides (rain shelter house). Net screen and rain shelter houses had either 0 or 30% shading. Cultivation type had significant effect and shading had a minor effect on bulb production. The greatest yield and quality of produced bulbs were obtained in the rain shelter house with 30% shading. From the results of this study, it is concluded that dispersed production of high quality cut lily flowers and bulbs could be achieved during the summer in highland.

• FLOWER RESEARCH JOURNAL
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• v.16 no.4
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• pp.291-294
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• 2008

Cymbidium 'Honey Girl' was developed in 2005 by the National Horticultural Research Institute, Rural Development Administration. This cultivar came from cross between Cym. 'Yakoto' and Cym. 'Marian Simplicity' in 1995. Fifty seven seedlings were obtained after planting and acclimatization in green house. In 1999, a line was selected by its performance such as flower color, leaf shape, flower stalk, and vigorous growth which was named 'Wongyo F1-13'. The line code '9521928'($V_2$) had uniformity and excellent characteristics. The selected line was named as 'Honey Girl' after second characteristics test. This cultivar had white color ('WN 155B') and medium sized leaves and flowers (average leaf length is about 57 cm and width of flower is about 7.7cm) with many flowers and erect flower stalks. Blooming begins from the end of November to December under the normal culture conditions.