• Journal of the Korean Chemical Society
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• v.23 no.4
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• pp.206-209
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• 1979

Empirical force-field calculations have been applied to eight 1,6-anhydropyra-noses, the crystal structures$^{13{\sim}21}$ of which have been studied by single crystal X-ray or neutron diffraction analysis. The theoretical calculations reproduce closely the variations in conformation between $^1C_4$ and $E_0$, which are observed in the pyranose rings. The smaller conformational differences in the five-membered anhydro ring are not so well predicted. The calculated C-C bond lengths agree with those observed within 0.012${\AA}$ with one exception. The C-O bond lengths show a larger deviation, 0.027${\AA}$. The non-hydrogen atom valence angles agree within 1.9$^{\circ}$.

• Journal of Korean society of Dental Hygiene
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• v.21 no.2
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• pp.109-118
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• 2021

Objectives: This study aimed to investigate the association between interpersonal relationships and the 4C core competencies of dental hygiene students. It also examined how interpersonal competence can be enhanced by the development and application of programs so that the 4C core competencies of university students can be improved. Methods: A survey was conducted from March to May 2019 on students from the Department of dental hygiene in Busan, South Korea, and 177 valid responses were analyzed. The general characteristics of the students were calculated using frequency and percentage, and their degree of 4C core competencies and interpersonal abilities were expressed as means (±standard deviation). Multiple regression analysis was used to analyze the effects of interpersonal competence on the 4C core competencies. Results: The findings revealed the factors affecting the 4C core competencies as; (a) communication ability was affected by interpersonal cognition and confidence building; (b) critical thinking ability was affected by person-oriented, self-expression, and confidence building; (c) creative problem-solving ability was affected by self-confidence, person-orientation, self-expression, and confidence building, and (d) cooperative self-efficacy was affected by person-oriented and confidence building. Conclusions: Based on the above findings, it is necessary to develop systematic program items and education systems that can effectively develop interpersonal competency, and thereby improve 4C core competencies among students.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.21-26
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• 2002

This paper is intended to verify the efficiency of anti-freeze agent and insulating form by analyzing the temperature history and the property of strength-increase about the concrete that is placed in the insulating form and normal form, using new type anti-freeze agent in batcher plant According to the results about the temperature history, while the lowest temperature shows 3$^{\circ}C$ in case of normal concrete + euroform, 4$^{\circ}C$ in case of normal concrete + insulating form, it shows 6$^{\circ}C$ in anti-freeze agent + the insulating form, so the effect is most favorable. The compressive strength with mixing anti-freeze agent or not, shows high in order of standard curing, structure-managing and open air-placed specimen and the concrete mixing anti-freeze agent shows the highest compressive strength-increase.

• Journal of Haehwa Medicine
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• v.20 no.1
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• pp.153-160
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• 2011

Objective : The objective of this study is to observe the effect of Pharmacopuncture of Anti-inflammatory Herbal compound(AiC) theraphy on elbow pain Methods : The patients diagnosed as lateral epicondylitis and treated mainly with Anti-inflammatory Herbal compound(AiC). After the application of herbal acupuncture, The NRS and ROM of elbow were assessed. Results & conclusion : Symptoms of the patient such as elbow pain and dysfunction were improved after above treatments. so, it is suggested that oriental medical treatment(Pharmacopuncture of Anti-inflammatory Herbal compound(AiC)) is effective on Tennis elbow.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1075-1082
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• 2008

Recently, coal ashes which are increasing annually are buried in ash ponds as industrial wastes. However, buried coal ashes can pollute ground water and ground due to leachate from coal ashes, which are serious environmental problem. Even though a lot of researches on recycling of coal ashes have been conducted, only 15% of coal ashes are recycled up to now. And those recycled coal ashes are not bottom ashes but fly ashes. So in this study, it was proved that Bottom Ash can be used as an alternative material to O.P.C(Ordinary Portland Cement) according to laboratory test results and test field construction. Also bottom ash is more economical and environmentally friendly than O.P.C.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2001.11a
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• pp.76-81
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• 2001

Recently, the structure is higher and larger, so that the application of high-strength concrete is increased, And as the development of construction skills, it is possible to place during the winter. Concrete work during winter is indispensible to shorten time of completion and cut costs. When concrete work during winter is placed, it has anxiety that concrete freeze at low temperature. As repetition of concrete's freezing cause reduction of durability, it is necessary for mixing to pay attention to air content and W/C ratios. Accordingly, in this study, we estimate the frost resistance by air content and W/C ratios, and development of strength after early-frost damage in the high-strength concrete during the cold weather. In this study, it could be confirmed that factors which were air content, W/C ratios and early curing period, affected on the frost resistance.

• Journal of the Korean Ceramic Society
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• v.33 no.5
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• pp.479-484
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• 1996

The tribological properties of ceramics are very important in the application to engineering ceramic parts such as mechanical seal slurry valve disc and so on. In this study the effect of graphite addition on the mechanical and tribological properties of RBSC/graphite composites were investigated. The composites were prepared by adding graphite powder to the mixture of SiC powder metallic siliconcarbon black and alumina. Bending strength water absorption friction coefficient the amount of worn out material at a certain time and maximum surface roughness(Rmax) of the prepared composites were measured and crystalline phases were examined with XRD. The composite containing 5 vol% graphite powder showed improved bending strength due to high green density and decreased friction coefficient and wear resistance. The friction coefficient and the wear resistance of the composite were increased by adding graphite powder up to 10 vol% They decreased however as increasing the amount of graphite powder more that 10vol% There was no linear relationship between the tribological properties and bending strength of the composites.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.172-175
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• 2003

ZnO:Al thin film for application to FBAR's bottom electrode using ZnO piezoelectric thin film were prepared by FTS, in order to improve the crystallographic properties of ZnO thin films because the ZnO:Al thin film and ZnO thin films structure is equal each other. So we prepared the ZnO:Al thin film with oxygen gas flow rate. Thickness and c-axis preferred orientation and electric properties of ZnO:Al bottom electrode were evaluated by $\alpha$-step, XRD and 4-point probe..

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.393-395
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• 2005

Super In Plane Switching (S-IPS) technology is applied for large TFT-LCD panels used in TV applications. It has a lot of advantages in comparison to the alternative, VA technology. S-IPS shows excellent viewing angle properties and fast response time between intermediate gray levels. If the performance parameters which describe the actual visual performance are considered, S-IPS is much more $advantageous.^{1)}$ However, it shows relatively low contrast ratio in diagonal direction compared to viewing angle characteristic in upper/down direction in S-IPS. In order to compensate the relatively low diagonal contrast ratio, Super-IPS applying for optical film developed, but Super-IPS still has the problem of color shift in black $pattern.^{2)}$ So we improved this problem by developing Enhanced Super-IPS.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.491-494
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• 2005

This study was carried out to examine application of surface adiabatic curing method in slightly cold weathering period. So, early aged freezing damage and compressive strength of concrete were examined through temperature analysis of construction concrete. Temperature analysis was carried out according to the average temperature, concrete placement completion time and surface adiabatic curing method. Analysis results show that additional curing plans are demanded in concrete construction below 0$^{circ}C$, surface adiabatic curing method is could apply in the average temperature more than -2$^{circ}C$ and curing method as heating are needed under -2$^{circ}C$.