• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.6
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• pp.47-53
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• 2004

This paper proposes an algerian for determining robot location using appearance-based paradigm. First, this algorithm compresses the image set using Principal Component Analysis(PCA) to obtain a low-dimensional subspace, called the eigenspace, and it makes a manifold that represent a continuous-appearance function. Neural network is employed to estimate the location of the mobile robot from the coefficients of the eigenspace. Then, Kalman filtering scheme is used for the fine estimation of the robot location. The algorithm has been implemented and tested on a mobile robot system. It is shown that the robot location is estimated accurately in several trials.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.8C
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• pp.775-782
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• 2005

In case of 3D reconstruction from dense data in uncalibrated sequence images, we encounter with the problem for searching many correspondences and the computational costs. In this paper, we propose a key frame selection method from uncalibrated images and the effective 3D reconstruction method using the key frames. Namely, it can be performed on smaller number of views in the image sequence. We extract correspondences from selected key frames in image sequences. From the extracted correspondences, camera calibration process will be done. We use the edge image to fed dense correspondences between selected key frames. The method we propose to find dense correspondences can be used for recovering the 3D structure of the scene more efficiently.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1116-1121
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• 2006

We studied on some techniques which are able to discriminate the difference between normal and infarcted myocardium by consecutive image analysis in B-mode echocardiogram. In order to analyze two-dimensional echocardiogram, we presented inter-frame and intra-frame analysis method throughout the complete heart cycle in closed-chest human and proposed new analysis parameters which are named HGE and LT. The analysis technique using the proposed parameters revealed quantitatively dominant features between normal and infarcted regions. The infarcted areas yield regions of higher intensity throughout the entire cardiac cycle, but normal tissue demonstrates greater variability throughout the entire cardiac cycle. Hence, we could verify that these parameters varying over the entire cardiac cycle are good indicators for the state of myocardium.

• The Korean Journal of Applied Statistics
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• v.30 no.6
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• pp.993-1004
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• 2017

A stratified sampling method is generally used with a sample selected using the same sample weight in each stratum in order to improve the accuracy of the sampling survey estimation. However, the weight should be adjusted to reflect the response rate if the response rate is affected by the value of the variable of interest. It may be also more effective to adjust the weights by subdividing the stratum rather than using the same weight if the variable of interest has a linear relationship with the continuous auxiliary variables. In this study, we propose a method to increase the accuracy of estimation using an informative sampling design technique when the response rate is an exponential function of the variable of interest and the variable of interest has a linear relationship with the auxiliary variable. Simulation results show the superiority of the proposed method.

• Applied Biological Chemistry
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• v.32 no.2
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• pp.143-147
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• 1989

The volatile compounds of McIntosh apples were separated and identified at the stage of climacteric maximum. 21 compounds were identified from head space method and classes of that were 13 kinds of esters, 6 of alcohols, an aldehyde and a ketone. From simultaneous steam distillation-extraction method, 37 compounds were identified and classes of that were 20 kinds of esters, 14 of alcohols, 2 of aldehydes and a ketone. Esters were the most abundant flavor component in the both methods and next was alcohols.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.05a
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• pp.17-20
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• 1997

이 연구에서는 국내에 산재되어 있는 금속광산들에 대한 토양환경오염을 조사하고 적절한 환경처리를 위한 기초자료를 제공하기 위하여 대표적인 연-아연광산, 동광산 및 금-은광산을 대상으로 As. Cd, Cu, Pb, Zn 등의 오염규모와 분산정도를 규명하고자 하였다. 연구대상지역으로 삼보 연-아연강산, 달성 동-텅스텐광산 그리고 구봉, 삼광, 금왕 금-은광산을 선정하여 이들 광산 주변에서 토양을 채취하여 화학분석을 실시하였다. 그리고 연속추출법을 이용하여 토양중에 존재하는 중금속의 존재형태를 규명하였으며 화학분해방법에 따른 중금속의 추출정도를 고찰하기 위하여 강산을 이용한 분해방법과 토양환경보전법에 제시된 방법을 비교하였다. 화학분석 결과, 삼보광산 주변의 상부토양 (0-15cm 심도)에서는 평균 11.8 $\mu\textrm{g}$/g Cd, 208 $\mu\textrm{g}$/g Cu, 2,700 $\mu\textrm{g}$/g Pb, 8,300 $\mu\textrm{g}$/g Zn이 검출되었으며 일부 농경지에서는 토양환경보전법의 우려기준을 초과하는 중금속이 검출되어 광산활동에 의한 토양오염이 심각함이 조사되었다. 달성광산 주변 토양에서도 다량의 중금속이 검출되었으며 (평균 4.4 $\mu\textrm{g}$/g Cd, 1,950 $\mu\textrm{g}$/g Cu, 1,030 $\mu\textrm{g}$/g Pb, 419 $\mu\textrm{g}$/g Zn) 특히 As (평균 2,500 $\mu\textrm{g}$/g)의 오염이 심각하였다. 그리고 대표적인 금은광산인 구봉, 삼광 및 금왕광산에서는 광미와 선광장 주변에서 다량의 중금속과 As가 검출되었다. 이 연구 결과, 이들 점오염원에 대한 오염정도가 심각하므로 이를 적절하게 처리할 수 있는 오염복구사업이 실시되어야할 것으로 판단된다.

• Journal of the Korean GEO-environmental Society
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• v.3 no.1
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• pp.13-26
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• 2002

In this study, column diffusion tests for Cd and Zn were conducted at $15^{\circ}C$ and $55^{\circ}C$ to investigate a temperature effect on effective diffusion coefficient. An increase in temperature from $15^{\circ}C$ to $55^{\circ}C$ caused up to ten times larger diffusion coefficient for each heavy metal. Besides, it caused the increased retardation of heavy metals, and hence the effective diffusion coefficient should be overestimated as we use an overestimated retardation factor to calibrate the coefficient. The results of sequential extraction analyses showed that Zn was occluded in carbonate phase and this trend was getting prominent with the increase in temperature. As for Cd, it was partitioned mainly in the exchangeable phase(over 60%) at any temperature.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.1
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• pp.54-61
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• 2001

A software package to classify acoustic emission (AE) signals using the wavelet transform and the neural network was developed Both of the continuous and the discrete wavelet transforms are considered, and the error back-propagation neural network is adopted as m artificial neural network algorithm. The signals acquired during the 3-point bending test of specimens which have artificial defects on weld zone are used for the classification of the defects. Features are extracted from the time-frequency plane which is the result of the wavelet transform of signals, and the neural network classifier is tamed using the extracted features to classify the signals. It has been shown that the developed software package is useful to classify AE signals. The difference between the classification results by the continuous and the discrete wavelet transforms is also discussed.

• Analytical Science and Technology
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• v.7 no.3
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• pp.413-419
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• 1994

The determination of the neuromuscular blocking agents vecuronium bromide(VeBr) in biological fluids has been investigated. The method depends on the formation of insoluble red complex between vecuronium bromide and rose bengal in aqueous layer. The amount of vecuronium bromide was calculated from that of extracted rose bengal which was determined by spectrofluorimetry or HPLC/fluorescence detection method. It was possible to analyze VeBr in the range of $2{\sim}32{\mu}g/ml$(r=0.998 for water soln., 0.999 for urine, 0.996 for plasma). This method was applied to the analysis of VeBr in biological fluids, urine and plasma.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.894-898
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• 1999

Aroma components of Ookjook tea made from Polygonatum involucratum Maxim roots were collected and identified. The extraction of aroma compounds was accomplished by a simultaneous distillation and extraction method using a Likens and Nickerson's extraction apparatus. The concentrated extract was analyzed and identified by GC and GC-MS. The most abundant aroma components of this tea were furanic compounds including 2-furfural, 2-methyl-dihydro-3(2H)-furanone, 2-acetylfuran and 5-methylfurfural. These compounds seem to be originated from the thermal degradation of carbohydrates during the roasting process. Alkylpyrazines and acids including propionic acid increased slightly during the period of manufacturing process of Ookjook tea. Furanic compounds originated from the thermal degradation of carbohydrates and alkypyrazines from aminocarbonyl reaction seemed to be the important contributors to the aroma of the Ookjook tea.