• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.976-980
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• 2001

In this study, P $b_{0.88}$(L $a_{a}$N $d_{l-a}$)$_{0.08}$(M $n_{1}$3/S $b_{2}$3/)$_{0.02}$ $Ti_{0.98}$ $O_3$system ceramics were manufactured for 20 MHz class resonator application. Electromechanical coupling factor, mechanical quality factor and dynamic range of 3rd overtone thickness vibration mode were measured as the variations of La and Nd molar ratio. Mechanical quality factor and dynamic range at $\alpha$=0.6 composition ceramics showed the highest value of 2, 691 and 52.37 dB, respectively. The tempearture coefficient of resonant frequency measured from -2$0^{\circ}C$ to 8$0^{\circ}C$ showed an excellent value of 5ppm/$^{\circ}C$ at $\alpha$ = 1 composition ceramics. ceramics.s.

• 한국실내디자인학회논문집
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• 제17권3호
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• pp.68-76
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• 2008

This study investigated composition elements and estimation of image in lobby from user viewpoint that is the central space of local cultural institution, and spectator mainly utilizes. Progress process of study develops investigation device including literature investigation, professional panel and lobby space image measurement tool through on-the-spot probe and, executed supporting research to spectator. As the result of the study, first, lobby space image exerts absolute effect to local cultural institution image-building, and is grasped on constituent that floor, ceiling, entrance and lighting and decoration is important in image-building of lobby space. Second, the image of the important lobby space was grasped in order of convenient image(M = 3.98) bright image(M = 3.87), and cozy image(M = 3.80). Third, the results on investigating semantic structure of the lobby image, emotional factor, styling factor, spatial factor, and peculiar factor are composed of important factors that decides image of lobby space. Fourth, as the result of image analysis for lobby space, the degree of satisfaction for the local cultural institution was entirely low against the importance. In particular, the image for convenience, individuality, locality and dignity was not sufficient in all the three places. Therefore, lobby design of local cultural institution shall also suggest more various lobby space image from culture oriented viewpoint.

• 한국도로학회논문집
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• 제19권5호
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• pp.77-88
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• 2017

PURPOSES : It is necessary to clarify the rheological properties of cement paste as a basic research in the development of mechanistic concrete mix design. The rheological properties of cement paste with different binder types, mix propositions, and with/without high range water reducers have been analyzed. METHODS : In this study, ordinary Portland cement, fly-ash, blast furnace slag, silica fume, and limestone powder were used as binders. The range of water-binder ratio was 0.3-0.5, and a total of 30 different mixes have been tested. The slump flow test, V-funnel test, and Dynamic Shear Rheometer (DSR) test were performed to analyze the rheological properties of cement paste. RESULTS : As a result of the slump flow test, it was found that the composition ratio of the binder contents greatly affected the paste flow when the high range water reducers were added. The results of V-funnel test showed that when the water-binder ratio was decreased without high range water reducers, the binder composition ratio had a large effect on the passing time of the V-funnel tester, but with high range water reducers the impact of the binder composition ratio was decreased. The slump flow and V-funnel have a certain relationship with the rheological factors (yield stress and plastic viscosity), but the correlation was not significant. Finally, we proposed the M-value considering the density and specific surface area of the binder. The correlation between rheological factors and M-value were better demonstrated than experimental values, but there is still a limit to predict the rheological factor in general mix design. CONCLUSIONS :In this study, the rheological properties of cement paste were analyzed. The binder type, composition ratio of binder, and with/without high range water reducers have combined to provide the complex effects on the rheological properties of cement paste. The correlation between the proposed M-value and rheological factor was found to be better than experimental results, but needs to be improved in the future.

• 한국실내디자인학회논문집
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• 제19권3호
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• pp.224-233
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• 2010

As urban function has become diversified and complicated, multifunctional complex facilities to satisfy new functional desires are necessary. Since local autonomy started, many facilities previously run and managed by central administrative agencies are now under management of localities, and functionally, the necessity for governments complexes town to satisfy diverse taste of populace such as creating local community becomes imminent. Analyzing characteristics by space composition factor of the public health center, newly built as part of such governments complexes town and understanding required area of each part, this project is to be used as basic material for construction plan of public health center that is equipped with local characters while devising construction of the public health center in the governments complexes town. Research method is to analyze four public health center facilities located in governments complexes town sites built after 2007, among twenty five public health centers in Seoul, by spatial functions. Also, based on statistical documents of usage of public health center facilities, research over spatial compositional factors and area composition has been conducted. As a result, connectivity between local government building located inside the governments complexes town and public health center and that of spatial composition factor by part, area ratio by part and floor type of public health center are comprehended. Connectivity type of public health centers are divided into horizontal and vertical connectivity and it is found that spatial composition of public health center is compartmentalized into low level, mid level and high level, to make access by users easier. Level type is decided as radial, rotational and combined by hallway connecting facilities.

• 대한본초학회지
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• 제24권1호
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• pp.121-131
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• 2009

Objectives：This study was designed to investigate the effects of herbal composition and fermented Cervi Pantotrichum Cornu on the growth of longitudinal bone in the adolescent male rats. Methods： Longitudinal bone growth was measured by fluorescence microscopy. To examine the effects on the growth plate metabolism, the total height of growth plate and the induction of local insulin-like growth factor-1 (IGF-1) and bone morphogenetic protein-2 (BMP-2) were measured. Results： The herbal composition treatment enhanced longitudinal bone growth and total heght of growth plate and promoted the induction of local IGF-1 and BMP-2 of growth plate. Conclusions： This study showed that the herbal composition have the effect of bone growth in adolescent rats and might be used for the growth delayed adolescent and inherent growth failure patient.

• 대한한의학방제학회지
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• 제26권3호
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• pp.207-221
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• 2018

Objectives : Present study investigated hepatoprotective effect of Haegan-jeon extract (HE) and tried to elucidate molecular mechanism involved. According to molecular mechanism, present study optimized herbal composition of HE (op-HE) and compared in vitro and in vivo hepatoprotective effects of op-HE to HE. Methods : For in vitro experiments, HepG2 cells were exposed to arachidonic acid (AA, $10{\mu}M$) and iron ($5{\mu}M$) for inducing oxidative stress. Cell viability, GSH contents, $H_2O_2$ production, mitochondrial membrane potential, immunoblot and reporter gene assay were performed to investigate cytoprotective effects and responsible molecular mechanisms. For in vivo experiments, hepatoprotective effect of HE and op-HE were assessed on $CCl_4-induced$ liver injury mice model. Results : HE pretreatment prevented AA+iron-mediated hepatocytes apoptosis. In addition, AA+iron-induced mitochondrial dysfunction, $H_2O_2$ production, glutathione depletion were reduced by HE pretreatment. In addition, nuclear factor erythroid 2-related factor 2 (Nrf2) phosphorylation, antioxidant response element (ARE)-driven reporter gene activity, and antioxidant genes expression were increased by HE. Based on reporter gene and MTT assays, we found that op-HE consisting three medicinal herbs also significantly increased transactivation of Nrf2 and reduced the AA+iron-mediated cytotoxicity. Moreover, in $CCl_4-induced$ liver injury mice model, HE-op had an ability to ameliorate $CCl_4-mediated$ increases in serum alanine transferase and aspartate aminotransferase activity, hepatic degeneration, inflammatory cell infiltration, and collagen deposition. Hepatoprotective effects of op-HE were comparable to those of HE. Conclusions : Present study suggests that op-HE as well as HE exhibit hepatoprotective effect against oxidative stress-mediated liver injury via Nrf2 activation.

• Journal of Microbiology
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• 제42권2호
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• pp.69-73
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• 2004

Vibrio vulnificus, a Gram-negative bacterium found in estuarine waters, is responsible for over 95％ of all seafood-related deaths in the United States. As a result of a temperature downshift to 5$^{\circ}C$, this organism enters the viable but nonculturable (VBNC) state. Changes in the membrane fatty acid (FA) composition of V. vulnificus may be a contributing factor to the ability of this organism to enter into and survive in the VBNC state. This hypothesis was tested by incubating the organism at 5$^{\circ}C$ in arti-ficial sea water and analyzing the cells' FAs during the initial hours of temperature and nutrient down-shift. Prior to downshift, the predominant FAs were 16:0, 16:1 and 18:0. During the first four hours of downshift, statistically significant changes occurred in 15:0, 16:1, 16:0, 17:0, and 18:0. These results indicate that changes in FA composition occur prior to entry of V. vulnificus into the VBNC state, suggesting that the ability to maintain membrane fluidity may be a factor in this physiological response. Cells in which fatty acid synthesis was inhibited did not survive, indicating that active fatty acid metab-olism is essential for entry of cells into the VBNC state.

• 한국농촌건축학회논문집
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• 제10권1호
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• pp.51-58
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• 2008

This study examined the present condition and problems of rural apartment house through documentary survey and considered the social necessity and concept of rural apartment housing. The aim of this study is to suggest the social necessity and spatial composition factor of rural apartment housing. The results of this study are as follows. First, rural apartment houses are generally adjacent to production and natural environments, and tend to be constructed in small complex of 50 households or less with the lack of convenient facilities. Second, the ultimate goal of rural apartment housing plans is to improve the livability, community, sustainability and rurality on the basis of the basic direction of rural areas. Third, it is necessary to install storages within the apt. complex and secure a buffer zone where people can wash their hands before entering the houses. Fourth, rural apartment housing should adopt the space components of auxiliary facilities including storages for agricultural products and farming appliances, common workshops, field attached to home, and washrooms in consideration of the conditions of rural areas different from urban apartment housing.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.57-73
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• 2020

A study was conducted to present the criteria for evaluating the revegetation method of the slope of the expressway. The results of comparative analysis between 2019-2020 field survey and existing research data (2015-2016) are as follows. Soil is a very important factor at the beginning of revegetation work. However, after the plant has settled, the importance of the soil composition diminishes. Among the plants used, the number of plants sown at the beginning gradually decreases. And it changes as it competes with invading plants. Among the plants used for sowing, it was found to affect the vegetation composition in the order of exotic grass > native herb and wildflower > native tree. Plant coverage is continuously evaluated as an important factor regardless of the time. The vegetation structure on the slope will change continuously over time. New items need to be evaluated in situations where a lot of time has elapsed since the application of revegetation work. It is desirable to use the current evaluation standard only to perform the evaluation within 1 to 2 years. In the long run, it is necessary to establish a new evaluation standard that adjusts the weights of each item.

• 한국보건간호학회지
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• 제31권2호
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• pp.220-233
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• 2017

Purpose: This study compared the body composition and health conservation of low and high physical activity groups in professional retired elderly. Methods: The participants were 132 professional retired elders using a university of education for the elderly and senior welfare centers in D and K city. Data were collected through interviews from November to December in 2015. The body composition was measured using an Inbody 230 and the health conservation was measured using Sung's (2005) Health Conservation Scale. The low and high physical activity groups were divided by CHAMPS (The Community Healthy Activities Model Program for Seniors Questionnaire). The collected data were analyzed using a $x^2$ test, independentt-test, andbinary logistic regression using the SPSS/WIN 20.0 program. Results: The body composition (body mass index, body fat percentage, and fitness score) and health conservation score were higher in the high physical activity group than in the low physical activity group. The result shows that the body weight (OR=10.62) is the highest risk factor influencing the physical activity in professional career-retired elders. Conclusion: These results suggest that to induce physical activity level among professional retired elders, nursing interventions are needed to increase the health conservation and body composition, particularly in controlling the body weight.