• 조명전기설비학회논문지
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• 제21권3호
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• pp.11-17
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• 2007

고제철설비 같은 매우 가혹한 환경 조건에서 뜨거운 철판의 온도를 측정하는 적외선 온도측정시스템을 개발하였다. POSCO 광양제철소 철판 압연공정에서 3개원간의 현장 테스트를 수행하였다. 현장 시운전에서 개발된 시스템의 신뢰성을 확인하였다. A2TPMI 센서의 비선형 방정식을 풀기위해 커브핏 방법을 통해 보정하고, 각 레인지당 $1[^{\circ}C]$이하의 정밀도로 25[msec]처리 속도를 확보하였다. 실험에서는 POSCO에서 받은 시험성적과 USN 기반에서 폴링방식을 통한 트래픽 모니터링을 통해 효과적인 온도감시 시스템임을 확인하였다.

• 한국멀티미디어학회논문지
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• 제12권1호
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• pp.50-57
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• 2009

본 논문은 3차원 다각형 모델에서 특징 선을 추출하기 위한 방법에 대해 제안한다. 이산 곡면으로 이루어진 다각형 모델에서 특징 선을 추출하기 위하여 기존 방법에서는 전역적인 음함수 곡면 맞춤 기법(Implicit Surface Fitting)을 이용하여 모델의 꼭지점에서 곡률과 곡률 미분 값을 측정하였다. 이러한 방법은 다각형 모델의 꼭지점에서 음함수 곡면으로 정확하게 투영할 수 있도록 사용자의 정의 파라미타를 찾아야 하며, 특징 추출을 위한 많은 계산 시간을 요구한다. 그러나 제안 방법은 지역적 음함수 곡면 맞춤 기법을 이용하여 모델의 꼭지점에 근사된 곡면을 통해 미분 정보를 측정한다. 측정된 미분 정보를 통해 쉽게 각각의 모서리에서 제로-클로싱을 통해 특징 점을 추출하고, 곡률 방향을 따라 추출된 점들을 연결하여 특징 선을 생성한다. 여러 가지 다각형 모델에서 실험을 하였고 기존 방법보다 빠르며 높은 품질의 특징 선을 추출한다.

• Computers and Concrete
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• 제19권5호
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• pp.527-535
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• 2017

In this study, an aging deformation statistical model for a unique high and steep rock slope was proposed, and the aging characteristic of the slope deformation was better reflected. The slope displacement was affected by multiple-environmental factors in multiple scales and displayed the same tendency with a rising water level. The statistical model of the high and steep rock including non-aging factors was set up based on previous analyses and the study of the deformation and residual tendency. The rule and importance of the water level factor as a non-aging unit was analyzed. A partitioned statistical model and mutation model were established for the comprehensive cumulative displacement velocity with the monitoring study under multiple factors and multiple parameters. A spatial model was also developed to reflect and predict the whole and sectional deformation character by combining aging, deformation and space coordinates. A neural network model was built to fit and predict the deformation with a high degree of precision by mastering its feature of complexity and randomness. A three-dimensional finite element model of the slope was applied to approach the structure character using numerical simulations. Further, a three-dimensional finite element model of the slope and dam was developed, and the whole deformation state was analyzed. This study is expected to provide a powerful and systematic method to analyze very high, important and dangerous slopes.

• 한국의류산업학회지
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• 제13권4호
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• pp.624-634
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• 2011

The purpose of this study is to develop the pattern of safety clothes used at flat or mountainous areas and to identify the pattern of safety clothes by conducting experimental evaluation of virtual wear. Three subjects were selected, based on fire fighters' physical constitution. A prototype design for safety clothing was determined after in-depth interviewing of professionals and surveying of Forest service staff and related agency. Wearing test should be carried out in the order of pattern making, virtual and real wearing evaluation. For data analysis, technical statistical values should be obtained by using body measurements of subject, frequency analysis and T-test. The jacket is designed to have a front extension and the entire length of clothing enough for wearer to put on it over ordinary shirts or sweater. The collar of jacket is of round type. Cyber reality enables to identify the movement and activity of virtual fitting model and to find out errors or problems in safety clothing prior to on-the-spot wear test, thus raising the precision level of pattern. There was significant difference between real and virtual fit preference. The results show that the virtual try-on system need the development of a specific style.

• 대한공간정보학회지
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• 제17권4호
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• pp.61-66
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• 2009

본 연구는 넓은 지역의 DEM 생성 시 하드웨어 성능에 따라 자료를 부분적으로 처리해야 하는 불편을 개선하고 DEM의 정밀도를 개선하는 것에 그 목적이 있다. 본 연구에서 개발된 DEM Generator 프로그램은 대용량 LiDAR 자료, 수치지형도 자료에 스트리밍 방식을 적용하여 인덱싱 및 델로니 삼각망 생성을 수행하고, Natural Neighborhood 또는 TIN 보간법을 적용한 가상 파일을 생성하여 특정한 해상도로 대규모 지역의 DEM 및 음영기 복도를 효율적으로 생성하도록 설계되었다. 최종적으로 생성된 DEM 및 음영기복도는 GeoTIFF 포맷으로 제공된다. DEM Generator 프로그램은 GIS, 기상, 환경 분석 등 넓은 지역의 DEM 생성이 필요한 분야에서 기존의 부분적인 DEM 생성 및 인접 처리 과정에 의해 발생했던 시간적 경제적 손실을 절감시킬 수 있을 것으로 판단되며, 추가적인 인접 및 수정 작업이 불필요하여 DEM의 정밀도를 높일 수 있을 것으로 판단된다.

• 대한치과기공학회지
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• 제38권3호
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• pp.119-125
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• 2016

Purpose: The purpose of this study is to evaluate the marginal gap of all-ceramic crowns fabricated by CEREC$^{(R)}$ in-office CAD/CAM system. Methods: The mandibular first molar was selected as the abutment for the experiments. Thirty working models were prepared. VITA Mark II(VM) and VITA Enamic(VE), LAVA Ultimate(LU) blocks were milled using CEREC MCXL with CEREC 3D system to construct 10 crowns for each groups. To measure marginal gap, milled restorations were examined under digital microscope with scale under 160x magnifications. The results were statistically analyzed using the one-way ANOVA and Tukey's HSD test(${\alpha}=0.05$). Results: There was no significant difference in the marginal gap regarding to ceramic materials(p>0.05). Conclusion: Single crowns fabricated using CEREC in-office CAD/CAM system provided clinically acceptable marginal gap. This confirmed that the type of ceramic material used does not determine the precision of fit of a prosthesis.

• Environmental Engineering Research
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• 제22권2호
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• pp.162-168
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• 2017

Rainfall is one of the most important phenomena of the natural system. In Bangladesh, agriculture largely depends on the intensity and variability of rainfall. Therefore, an early indication of possible rainfall can help to solve several problems related to agriculture, climate change and natural hazards like flood and drought. Rainfall forecasting could play a significant role in the planning and management of water resource systems also. In this study, univariate Seasonal Autoregressive Integrated Moving Average (SARIMA) model was used to forecast monthly rainfall for twelve months lead-time for thirty rainfall stations of Bangladesh. The best SARIMA model was chosen based on the RMSE and normalized BIC criteria. A validation check for each station was performed on residual series. Residuals were found white noise at almost all stations. Besides, lack of fit test and normalized BIC confirms all the models were fitted satisfactorily. The predicted results from the selected models were compared with the observed data to determine prediction precision. We found that selected models predicted monthly rainfall with a reasonable accuracy. Therefore, year-long rainfall can be forecasted using these models.

• 구강회복응용과학지
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• 제18권4호
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• pp.313-320
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• 2002

The purpose of the present study was to evaluate the marginal discrepancy and topography of artificial crown on teeth extracted due to severe periodontal disease. Twenty specimens were invested into metamethylacrylate resin and cutted into vertical slices along with the long axis of tooth. The selected marginal discrepancy between the outer edge of the crown and the finishing line of abutment was examined by stereo- microscope(Olympus, PM-VSP-3, Japan) at magnification of up to 10, and the topography of finishing margin on crown was observed by stereomicroscopeat magnification of up to $70{\times}$. The results were as follows. (1) The mean marginal discrepancy between extracted tooth and artificial crown were $50.82{\mu}m$. (2) There was a considerable difference in the microstructure of finishing margins among specimens. Microscopic Structure on finishing margin showed indefinite line, poor fit (open, underextended and overextended), distorted margin, and surface roughness. This study suggested that there could be necessary to consider the response of periodontium to the emergence profile of natural tooth and precision of marginal geometry while establishing treatment planning for the reconsruction of the artificial crown.

• 대한화학회지
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• 제55권4호
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• pp.620-625
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• 2011

구리수은막 전극(CBMFE)으로 전위차 역적정함으로써 이소니아자이드(INH)를 정량하는 간단하고 빠른 방법이다. 순수한 형태와 투약형태에 대해서 1.0-10.0 mg 범위에서 정량 할 수 있도록 적정조건을 설정하였다. 방법의 정밀도와 정확도는 통계적인 방법으로 평가되었으며, 정제와 시럽속에 함유된 INH 정량법은 F-시험과 t-시험을 통하여 영국약전(BP) 방법과 비교하였다.

• Communications for Statistical Applications and Methods
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• 제26권5호
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• pp.445-461
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• 2019

It is possible that data are not always fitted with sufficient precision by the existing distributions; therefore this article presents a methodology that enables the use of families of asymmetric distributions as alternative probabilistic models for survival analysis, with censorship on the right, different from those usually studied (the Exponential, Gamma, Weibull, and Lognormal distributions). We use a more flexible parametric model in terms of density behavior, assuming that data can be fit by a distribution of stable distribution families considered unconventional in the analyses of survival data that are appropriate when extreme values occur, with small probabilities that should not be ignored. In the methodology, the determination of the analytical expression of the risk function h(t) of the $L{\acute{e}}vy$ distribution is included, as it is not usually reported in the literature. A simulation was conducted to evaluate the performance of the candidate distribution when modeling survival times, including the estimation of parameters via the maximum likelihood method, survival function ${\hat{S}}$(t) and Kaplan-Meier estimator. The obtained estimates did not exhibit significant changes for different sample sizes and censorship fractions in the sample. To illustrate the usefulness of the proposed methodology, an application with real data, regarding the survival times of patients with colon cancer, was considered.