• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.681-691
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• 2017

In this research, life cycle inventory database (LCI DB) was developed for elastomeric bearing employing life cycle assessment (LCA) methodology additionally the reliability improvement rate in the evaluation of the environmental load of the bridge was analyzed. As are result of impact assessment by 6 major impact categories, production of elastomeric bearing puts on environmental impact in the order of resource depletion, global warming, photochemical oxidant creation. and among a wide variety of input, steel plates contributes in most of the impact categories. As a result of applying the elastomeric bearing LCI database constructed in this study, the environmental loads increased by 0.53% on average, and the cut-off based on the cost of input materials increased by 11.36%. It is anticipated that it will be possible to improve the credibility and to provide data based on current production technology, such as estimating GHG emissions and evaluating environmental load, by constructing elastomeric bearing LCI DB.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.865-868
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• 2008

As a part of a series of study, this study reviewed the fire proof characteristics of high performance concrete RC column members using non-stripping form that accompanied metal lath lateral confinement to prevent spalling of high performance concrete which is increasingly used recently, and the results are as follows. Flow and air amount both satisfied target range, and compressive strength, over 80MPa at age 28 days, showed high strength range. As for spalling characteristics, in the case of plain in which no fiber is mixed, severe spalling occurred, and in the case of 0.05% nylon("NY" hereinafter)+polypropylene("PP" hereinafter) fiber mixture, only surface area experienced partial spalling. Regarding non-stripping form changes, both non-stripping 25-20 and non-stripping 50-20 experienced spalling at finish material area, and non-stripping 50-20 showed better spalling proof performance than non-stripping 25-20. In the case of non-stripping 50-40, spalling was prevented, and while mass reduction rate was less than 10%, its temperature hysteresis showed the most excellent fire proof performance with base metal surface area maximum temperature $376.1^{\circ}C$.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.8
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• pp.89-121
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• 2003

Das Ziel der vorliegenden Arbeit ist zweierlei: Einerseits soll in Anlehnung an Gereon $M\"{u}ller(M\"{u}ller{\;}2000a,{\;}u.a)$ demonstriert werden, dass sich die $Optimalit\"{a}tstheorie$ (OT im folgenden) als eine neue Alternative $f\"{u}r$ syntaktische Beschreibungen des Deutschen auffassen $la\'{u}{\ss}t$; andererseits wird unter dem Gesichtspunk der Kognitionswissenschaft die $Plausibilit\"{a}t$ der OT als eine Theorie der menschlichen Kognition kritisch $\"{u}berpr\"{u}ft$. Diskussionen bzgl. der ersteren Zielsetzung deuten darauf hin, dass syntaktische Eigenschaften des Deutschen im Grunde durch $Kalkulationsvorg\"{a}nge$ $erfa{\ss}bar$ sind, bei denen unter mehreren miteinander konkurrierenden Kandidaten einer als optimal charakterisiert wird. Dabei spielen geordnete und im Prinzip verletzbare $Beschr\"{a}nkungen$ eine zentrale Rolle. Die $Beschr\"{a}nkungsordnung$ bestimmt, welcher Kandidat optimal sein sallte: ein Kandidat, der relativ niedriger eingestufte (oder ggf. gar keine) $Beschr\"{a}nkungen$ verletzt, $schl\"{a}gt$ alle anderen, die relativ $h\"{o}her$ eingestufte (oder ggf. eine einzige) verletzen. Der Gewinner wird dann als optimal und somit als wohlgeformt bezeichnet. Was die zweite Fragestellung anbetrifft, liegt es nahe, dass zentrale Annahrnen der OT im wesentlichen mit denen des Konnektionismus zu vereinbaren sind. Dies besonders in dem Sinne, dass beiden Ansatzen der Empirismus, das Konzept des Wettbewerbs und der $Flexibilit\"{a}t$(Verletzbarkeit, Interaktionen usw.) zugrundeliegen. Ist man also der Ansicht, dass eine neurologisch fundierte Sprachtheorie einer anderen vorzuziehen ist, die neurologische Grundlagen der Sprach nicht mit­$ber\"{u}cksichtigt$, so sollte man u. E. jeden OT -basierten Ansatz emsthaft in Betracht ziehen: Konnektionismus stellt sich $n\"{a}mlich$ die Aufgabe, eine Theorie der Informationsverarbeitung zu erzielen, die gerade die Art und Weise der Informations­verarbeitung des menschlichen Gehims simmuliert.

• Journal of Environmental Policy
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• v.8 no.3
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• pp.163-180
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• 2009

This study attempts to investigate the preference uncertainty of respondents involved in stating their Willingness to Pay (WTP). For the Contingent Valuation Method (CVM) survey, we employed two approaches using two split samples. The respondents of one sample were given the opportunity to express intensity of preference through Multi-bounded Discrete Choice (MBDC) WTP questions, while those in the other sample were given Dichotomous Choice (DC) WTP questions. By incorporating the two elicited degrees of preference uncertainty into examining the WTP responses, we compared the two approaches. In comparing the DC model with the MBDC model, the mean WTP for the DC model was similar to PRYES in the MBDC Model. We concluded that the MBDC model estimates the various mean WTP while considering the preference uncertainty.

• Journal of Periodontal and Implant Science
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• v.32 no.1
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• pp.249-255
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• 2002

Zea Mays L. has been known to be effective for improving tissue health and Magnoliae cortex to have effective antibacterial and antimicrobial activity against pathogenic microbes. The purpose of this study was to examine the antimicrobial effects of Zea Mays L. and Magnoliae cortex extract mixtures on periodontal pathogens(Prevotella intermedia, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans )and to examine the effects on human gingival fibroblast cellular activity. Zea Mays L. and Magnoliae cortex extracts and their mixtures were prepared with various mixing ratios (0.5:1, 1:1, 1.5:1, 2:1). These extracts were loaded to periodontal pathogen cultured petri dish for antimicrobial test and also loaded to cultured human gingival fibroblast for cellular activity test. Each test was repeated 3 times and data were analyzed by one-way ANOVA with 95% confidence level. Mixture of these two extracts showed greater amount of inhibition area on periodontal pathogen and more improved gingival fibroblast activity as Zea Mays L. ratio reduced. So, mixture ratio 0.5:1 (Zea Mays L. : Magnoliae cortex) group showed statistical significance in antimicrobial activity and cellular activity among various mixtures(p < 0.05). In conclusion, 0.5:1 (Zea Mays L. : Magnoliae cortex) mixture possessed best gingival fibroblast cellular activity and antimicrobial activity toward periodontal pathogens.

• Journal of Periodontal and Implant Science
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• v.26 no.2
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• pp.542-556
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• 1996

Previous studies have shown that Magnoliae cortex and Ginkgo biloba extracts were showed on the antimicrobial and anti-inflammatory action, in vitro. The purpose of this study was to evaluate on the effect of antimicrobial and anti-inflammatory activity of Magnoliae cortex and Ginkgo biloba extracts containing dentifrice in gingivitis. 70 subjects with gingivitis were divided into an experimental group which performed normal oral hygiene procedure with Magnoliae cortex and Ginkgo biloba extracts containing dentifrice and a control group which also performed normal oral hygiene procedure with the same dentifrice without the natural extracts and completed a doubleblind, cross-over study. At baseline and 3 weeks, subjects were assayed for clinical study by plaque index, gingival index, pocket depth, GCF rate, and microbiological study by subgingival dental plaque bacterial morphotypes by phase contrast microscopy, total anaerobes, total aerobes, Black pigmented bacteroides, A.actionomycetemcomitans, A.viscosus, C.rectus, Ssenguis; P.gingivalis, P.intennedia by bacterial culture and immunofluorescence microscopy. After 3 weeks using their respective dentifrices, reductions in the clinical indices of subjects were similar between the experimental dentifrice group and a control dentifrice group except for statistically significant much reductions in PI, GI, and GCF rate in the experimental dentifrice group as compared to control dentifrice group. Also statistically significant reductions in the motile rods and Spirochetes were found in both experimental group to compare with control group, however statistically much reduction in total anaerobes, Black pigmented bacteroides, and P.gingivalis, P.intennedia were found in the experimental dentifrice group as compared to control dentifrice group. This results indicates that Magnoliae cortex and Ginkgo biloba extracts containing dentifrice might be useful for elimination of gingival inflammation.

• Journal of Periodontal and Implant Science
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• v.38 no.2
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• pp.247-252
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• 2008

Purpose: Passive eruption is characterized by the apical shift of the dentogingival junction. As this occurs, the length of the clinical crown increases as the epithelial attachment migrates apically. Altered passive eruption occurs when the margin of gingiva is malpositioned incisally on the anatomic crown in adulthood and results in excessive gingiva. The purpose of this article is to evaluate esthetic results of crown lengthening procedure in altered passive eruption.s. Materials and Methods: Three patients who complained "My front teeth look too short" were included. Bone sounding with periodontal probe revealed that alveolar bone crest was close to CEJ. Based on the diagnostic information, a diagnosis of altered passive eruption was made. They were performed apically positioned flap procedure with osseous resection. Results: Six months later, all patients achieved favorable esthetic results and gingival margins were healthy and stable. Conclusion: When the diagnostic procedures reveal alveolar bone crest levels approximating the CEJ, apically positioned flap procedure with osseous resection is indicated.

• Journal of the Korean Home Economics Association
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• v.26 no.3
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• pp.135-152
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• 1988

The purpose of this study was to survey the improvement activities for the apartment house ; and to examine the relationship between apartment residents and their housing improvement activities in order to present some informations for the further studies and plans of apartment design and housing policy. Library and questionnaire survey methods were used in this research. the sample was taken from 102 housewives living in the apartments over 45 pyong (1602 sq. ft.), in Seoul, Data were analyzed with the SPSS using frequency, percentage, chi-square test, F-test, Duncan's multiple range test, η2, and C2. The results were as follows: 1. It was found that residents had experienced with 3.6 kinds of housing improvement activities. Living rooms, dining rooms, and kitchens in family living areas ; balconies and utility rooms in utility areas were improved for the physical convenience and quality of living. 2. This survey indicated that apartment residents evaluated thier housing condition as high, except storage spaces and outdoor noises. 3. About 80% of respondents were expected to live continuously in the current apartments because they were satisfied with the size of thier residences, However, they wanted to improve the inside of the entire apartment, especially bathrooms. 4. Variables which had a significant relationship in housing improvement activities in the past were the length of residence, the expected length of residence, and the characteristic of residence. 5. The expected length of residence, and the characteristic of residence were found to be effective variable for evaluating the current residence. 6. Finally, the expected length of residence, and the characteristic of residence were significant variables of the housing plan in the future. Housing improvement activities were prevalent recently and expected to be continued in the future. It can be said, therefore, that apartment residents have a long -term plan to live in one place rather than moving out ever two-three years.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.201-204
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• 2008

The Sectional Design Model(AASHTO LRFD) is appropriate for the design of typical bridge girders, slabs, and other regions of components where the assumptions of traditional engineering beam theory are valid. The shear resistance of a concrete member may be separated into a component, $V_c$, that relies on tensile stresses in the concrete, $V_s$, that relies on tensile stresses in the transverse reinforcement. The expressions for $V_c$ and $V_s$ apply to both prestressed and nonprestressed section, with the terms ${\beta}$ and ${\theta}$ depending on the applied loading(M, V, N, and T) and the properties of the section. With ${\beta}$ taken as 2.0 and ${\theta}$ as 45$^{\circ}$, the expressions for shear strength become essentially identical to those traditionally used for evaluating shear resistance. Recent large-scale experiments, however, have demonstrated that these traditional expression can be seriously unconservative for large members not containing transverse reinforcement. And This paper can present only a brief introduction to shear design of AASHTO LRFD and is to review of the technical difficulty.

• Journal of Korean Society of Forest Science
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• v.96 no.4
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• pp.483-493
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• 2007

The purpose of this study is to estimate the biodiversity conservation value of Heory stock in Sun-Cheon. Expected values of residents' Willingness To Pay (WTP) was estimated using Contingent Valuation Method (CVM) which is the most popular method in estimating conservation values of biological diversities. Three different estimation methods were used in statistical estimation, and the results were different from each other. Results of statistical analysis show that the expected value of WTP in logit model is highest, 5,772 Won per month. Those of A model which conducted OLS estimation using open ended questionnaire and B-1 model which conducted OLS estimation using dichotomous choice questionnaire were 1,978 Won per month and 2,391 Won per month respectively. The average expected value of WTP from three model was 3,380. This average value was expected to reduce methodological biases.