• The korean journal of orthodontics
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• v.32 no.1 s.90
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• pp.59-69
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• 2002

The purpose of this study was to evaluate the reproducibility of lateral cephalometric landmarks according to radiographic image enhancement, and to contribute to the identification of cephalometric landmarks. Lateral cephalograms of ten individuals were taken and stored into computer. The images were then enhanced up to four grades by Quick Ceph Image Pro$^{TM}$ on condition that the gray-scale equalization number was 50 and the detail enhancement number was 50. After thirty two landmarks were identified on monitor images by five observers, the deviations from the mean, the distances estimated between identified points and the mean point of five identified points, were evaluated for each landmark at each enhancement grade. Through the statistical analysis, following results were obtained. 1. In case of unenhanced radiographic images, the inter-observer reproducibility of the landmarks showed a large variation. 2. The comparison of deviation from the mean according to the degree of radiographic image enhancement for each landmark showed that the inter-observer reproducibility was significantly different at 5 landmarks. 3. The landmark of pterygomaxillary fissure showed higher reproducibility at enhancement grade 1 and 2 images than at unenhanced images. So did the landmark of posterior nasal spine at enhancement grade 1 images, and the landmark of menton at enhancement grade 2, 3 and 4 images respectively. The above results suggest that the reproducibility of some landmarks can be increased by radiographic image enhancement during the identification of the lateral cephalometric landmarks on the monitor.

• Journal of Navigation and Port Research
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• v.28 no.5
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• pp.395-403
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• 2004

The prevention of marine accidents has been a major topic in marine society and various policies and countermeasures have been developed, applied to the industries. The coastal VTS and navigational aids are considered as one of the effective methods to promote marine safety but they need relatively huge amount of budgets to build Thus prior to establishing these coastal VTS and navigational aids, it should be evaluated the navigational safety level in the coastal waterways from the Environmental Stress. So far as human beings are concerned, there are many types of fuzziness in the evaluation of navigational safety level. In order to reflect these fuzziness on this evaluation, this paper introduces the fuzzy integral suggested by Choquet to represent the fuzziness in the evaluation process. This paper aims to develop the method for this evaluation from the viewpoint of mariner's operational stress using the fuzzy measure and Choquet integral. In this paper, Korean coastal area is divided into 8 sectors and evaluated the priority for the needs of coastal VTS and navigational aids.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.4
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• pp.294-303
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• 2005

This paper describes the analysis results of a series f Round-Robin test that was performed to intercompare inspection and diagnosis techniques for characterization of pressure tube f a pressurized heavy water reactor under the Coordinated Research Project(CRP) of IAEA's nuclear Power Programme. For this test, six nations, Korea, Canada, India, Argentina, Rumania, and China that currently have pressurized heavy water reactors under operation involved, and the "KOR-1" pressure tube sample prepared by Korea was used. Two kinds of NDE technique, ultrasonic and eddy current test, were applied for these tests. The "KOR-1" pressure tube sample contains total 12 artificial flaws such as crack-like EDM notches, wear that is similar to the real flaws and can be produced on the pressure tubes during plant operation. Test results showed that seven laboratories from six nations detected all twelve flaws in "KOR-1" specimen by using ultrasonic and eddy current test methods, and ultrasonic test method was more accurate than eddy current test method in flaw detectin and sizing. ID flaws in pressure tube sample were more easily detected and accurately sized than OD flaws.

• Journal of Environmental Impact Assessment
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• v.24 no.2
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• pp.111-118
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• 2015

This study was conducted for the establishment of statistical method to determine the representative air quality monitoring station representing long-term ozone trends of Seoul. In this study, hourly ozone concentrations from 2002 to 2011 were used for further analysis. KZ-filter, correlation matrix, cluster analysis, and Kriging method were applied to select the representative station. The analysis based on correlation matrix found that long-term trend of ozone concentrations measured at Sinjung, Sadang, and Bun-dong showed a high correlation. The cluster analysis found that the former three stations belonged to the same cluster. The analysis based on Kriging method also showed that the former three stations were highly correlated with other stations in spatial distribution. Considering these results and the highest correlation coefficient of Sinjung station, the Sinjung station was the most suitable as the representative station used to understand the long-term ozone trend of Seoul. This result could be applied to understand long-term trend of other pollutants. Furthermore, this result can also be used to assess the appropriacy of spatial distribution of national air quality monitoring stations.

• Journal of Oral Medicine and Pain
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• v.20 no.1
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• pp.205-215
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• 1995

저자는 두개하악장애 환자에 대한 교합장치 치료시 group function 교합이 있는 환자에서도 canine guidance교합으로 변화시켜 치료함이 정당한지를 근전도학적 측면과 임상적 측면에서 알아보고자 Group function 교합을 가진 20명의 두개하악장애환자와 10명의 정상인을 대상으로 교합장치치료 전, 도중, 후의 좌우측 교근 및 전측두근의 근전도를 측정하고 두개하악장애지수를 조사한 수 이들 자료를 분석 평가하여 다음과 같은 결론을 얻었다. 1. 정상인군에서 최대이악물기상태의 좌우측 교근 및 전측두근의 근전도는 교합장치치료 도중의 cannine guidance교합시가 교합장치치료전후의 group function 교합시에 비해 낮게 나타났다(P<0.01). 2. 두개하악장애군에서 최대이악물기 상태의 좌우측 교근 및 전측두근의 근전도는 교합장치치료 도중의 canine guidance교합시 교합장치치료전후의 group functin교합시에 비해 낮게 나타났다. (P<0.01). 3. 두개하악장애지수는 교합장치치료 전에 비해 치료 후 감소되는 경향을 나타냈었다(P<0.01)

• Journal of the korean Society of Automotive Engineers
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• v.9 no.2
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• pp.5-11
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• 1987

선진국에서 사용되고 있는 자동차 배기정화 장치의 성능평가 시험방법은(CVS테스트, 유럽테스트, 일본테스트법 등)배기정화용 3원촉매 뿐만 아니라 그 부수장치의 성능을 포함한 포괄적인 평가방 법이므로 그 결과에 미치는 인자가 대단히 복잡하고 평가비용과 시간도 크게 드는 결점이 있어 서, 3원촉매만의 특성평가와 새로운 촉매의 연구개발의 방향을 추출하기 위하여서는 개선된 새로 운 성능 평가방법이 요구되고 있다. 이에 부응하여 모조합성 배기가스를 이용환 촉매성능측정장 치로부터 실제 엔진배기사스 측정장치에 이르까지 많은 평가시험 방법이 제안되었으나 아직 이러 한 시험방법에 의한 결과와 해석에 대하여서는 많은 관찰의 소지를 남기고 있는 것으로 보고 되 고 있다. 따라서, 본고에서는 기존상업적 3원촉매 뿐만 아니라 앞으로 연구 개발될 새로운 3원 촉매의 특성 및 성능평가에 관하여 미국, 일본 등을 포함한 선진제국의 현행 평가방법을 주로 초기단계에서 제안된 일본자동차연구소 연구보고 중심으로 하여 고찰하고자 한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4D
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• pp.323-333
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• 2012

This paper is aimed to recognize trends of various social groups about multiple transportation policies such as the crosswalk restoration by eliminating the pedestrian overpasses and the improvement or continuous extension of existing pedestrian overpasses, currently implemented in Busan, following the globally prevailing pedestrian-oriented transportation environment. Also, this paper utilizes Contingent Valuation Method (CVM) to evaluate the efficiency of individual alternatives in terms of respondent's willingness-to-pay (WTP). Consequently, survey participants preferred the crosswalk or improvement of the pedestrian overpasses rather than depending on the existing pedestrian overpasses. In addition, the WTP value for the crosswalk restoration is approximately 42,452 won per household per year, and, on the other hand, the WTP value for the improvement of existing pedestrian overpasses is approximately 36,793 won per household per year, implicating that the transportation policy makers are suggested to place more priorities on crosswalk restoration than the improvement of the existing pedestrian overpasses.

• Journal of Oral Medicine and Pain
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• v.17 no.1
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• pp.73-87
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• 1992

저자는 28명의 측두하악장애 환자와 31명의 정상인을 대상으로 최적기능교합의 개념에 입각하여 교합시의 치아접촉점을 동적이며 정량적인 방법으로 평가하여 교합안정장치의 사용으로 인한 교합안정성의 개선여부를 알아보고자 하였다. 이와 동시에 교근과 전측두근의 활성도를 측정하여 치료의 경과에 따른 근활성의 변화를 알아보기 위해 본 연구를 시행하였다. 측정항목은 개구범위, 두개하악장애지수, 치아접촉점 좌우균형치, 치아접촉점 전후균형치, 치아접촉점 평균시간간격, 치아접촉점의 개수, 접촉시간, 좌우측 교근과 좌우측 전측두근의 근활성, 근활성 비대칭 지수 등이었다. 이의 측정을 위해 T-Scan System, K-6 Diagnostic System 그리고 EM 2등을 사용하였으며 얻어진 자료에 대해 검정한 후 다음과 같은 결론을 얻었다. 1. 교합안정장치를 이용하여 측두하악장애 환자들을 4주간 치료한 결과 전반적인 임상증상이 호전되어 개구범위와 두개하악장애지수에 있어서 뚜렷한 개선이 있었다. 2. 측두하악장애 환자에서 최대 악물기시의 치아접촉점 좌우균형치및 평균시간 간격이 큰 것으로 나타나 치아접촉이 일어나는 순간의 교합안정성이 좋지 않은 것으로 평가되었다. 3. 치료 4주후 교하안정장치를 장착한 상태에서 측정한 치아접촉점 좌우균형치및 치아접촉점 평균시간간격은 치료전에 비해 개선된 것으로 나타났다. 4. 치료 4주후 치아접촉점의 전후방 분포가 구치부위로 이동되는 양상을 보였다. 5. 측두하악장애 환자에서 최대 악물기시의 좌우측 교근 및 전측두슨의 근활성은 정상인에 비해 낮에 나타났으며, 이는 치료기간 동안 감소되는 경향을 나타내었다. 6. 측두하악장애 환자에서 전측두근의 근활성 비대칭지수는 정상인에 비해 상당히 높게 나타났으며 이는 치료기간 동안 감소되는 경향을 나타내었다.

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.35-35
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• 2003

• Journal of the Korean Society of Marine Environment & Safety
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• v.11 no.2 s.23
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• pp.27-32
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• 2005

This paper suggests an evaluation of risk level for damage of marine accidents in SRRs. This paper intoduces a concept of fuzzy logic with the plenty of related literature riview, fuzzy measure t-seminormed fuzzy integral and in the Korean SRRs of RCC and RSC. The methodology of this paper is max. min composition of fuzzy extensive principle, defuzzifiation is centroid of gravity methods. And final evaluation value using t-seminormed fuzzy integral. At the result, the evaluation of risk level is especially over serious for marine accident of Mokpo, Tongyoung, Yeosu SRRs.. This paper recommends that many rescue vessels and equipments need to the reduction of risk level about those.