• Korean Journal of Remote Sensing
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• v.14 no.2
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• pp.129-136
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• 1998

This paper deals with a problem encountered in the course of constructing digital elevation model from a contour map. Deficiencies of widely used linear interpolation method is described, and an interpolation method for internal points of a single closed contour is proposed. Control points not on a plane are searched and interpolated. The method is applied to an artificial contour lines and real contour lines. The result shows natural and accurate reconstruction.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.289-296
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• 2012

Due to the topographical and climatic features of Korea, there is a strong possibility of a landslide. Recently, many landslides, caused by the improper land development, frequently occured at the mountain area every summer. Cheonan has been recognized to be relatively safe against landslide, but with the increased risk factors, systematic analysis of the landslide is required. In this paper, the topographical features of Mt. Seonggo in Cheonan City were extracted using contour maps, and water courses and basin areas in heavy rain were computed using the results. Conclusively, Mt. Seonggo areas were relatively safe in the view points of the length of water courses and rain-inflow, but in case of some narrow areas, sustainedly observation was required. Meanwhile, a contour map is proper to analyze the risk of landslide in the 1'st level in that it is more cost effective than other types of digital map.

• International Journal of CAD/CAM
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• v.3 no.1_2
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• pp.77-83
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• 2003

We propose two algorithms to generate (1) polygonal meshes and (2) developable surface patches far generalized cylinders defined by contours of discrete curves. To solve the contour blending problem of generalized cylinder, the presented algorithms have adopted the algorithm and related properties of LIDM (linear interpolation by direction map) that interpolate geometric shapes based on direction map merging and group scaling operations. Proposed methods are fast to compute and easy to implement.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1315-1318
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• 2003

In this paper, a neural network based approach using a self-organizing feature map is proposed for the segmentation of X ray images. A number of algorithms based on such approaches as histogram analysis, region growing, edge detection and pixel classification have been proposed for segmentation of general images. However, few approaches have been applied to X ray image segmentation because of blur of the X ray image and vagueness of its edge, which are inherent properties of X ray images. To this end, we develop a new model based on the neural network to detect objects in a given X ray image. The new model utilizes Mumford-Shah functional incorporating with a modified adaptive SOFM. Although Mumford-Shah model is an active contour model not based on the gradient of the image for finding edges in image, it has some limitation to accurately represent object images. To avoid this criticism, we utilize an adaptive self organizing feature map developed earlier by the authors.[1] It's learning rule is derived from Mumford-Shah energy function and the boundary of blurred and vague X ray image. The evolution of the neural network is shown to well segment and represent. To demonstrate the performance of the proposed method, segmentation of an industrial part is solved and the experimental results are discussed in detail.

• Transactions on Electrical and Electronic Materials
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• v.17 no.6
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• pp.363-368
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• 2016

Rectangular shape detection plays an important role in many image recognition systems. However, it requires continued research for its improved performance. In this study, we propose a strong rectangular shape detection algorithm, which combines the canny edge and line detection algorithms based on the perpendicularity and parallelism of a rectangle. First, we use the canny edge detection algorithm in order to obtain an image edge map. We then find the edge of the contour by using the connected component and find each edge contour from the edge map by using a DP (douglas-peucker) algorithm, and convert the contour into a polyline segment by using a DP algorithm. Each of the segments is compared with each other to calculate parallelism, whether or not the segment intersects the perpendicularity intersecting corner necessary to detect the rectangular shape. Using the perpendicularity and the parallelism, the four best line segments are selected and whether a determined the rectangular shape about the combination. According to the result of the experiment, the proposed rectangular shape detection algorithm strongly showed the size, location, direction, and color of the various objects. In addition, the proposed algorithm is applied to the license plate detecting and it wants to show the strength of the results.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.893-901
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• 2012

Aircraft noise model such as FAA Integrated Noise Model(INM) has recently been used for forecasting the impact of noise in a residential area near an airport and quantifying the effect of various options for noise mitigation. The noise modeling should be reliable and precise in order to ensure the quality of the results provided. In this study, the validation of the noise levels simulated by the INM against measurement data recorded continuously at multiple monitoring sites was discussed. As a result of validation, the quality of the input data used as a fixed point profiles for the INM was enhanced. The noise contour maps were designed as a way to evaluate the aircraft noise of the vicinity of the airfield. The results of this study indicate that the validation of aircraft noise model by the measurement data would be required for the accurate assessment of the aircraft noise levels.

• Journal of the Korean Solar Energy Society
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• v.30 no.3
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• pp.1-9
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• 2010

Since the horizontal global radiation and cloud cover are a main factor for designing any solar photovoltaic system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and cloud cover in Korea. The data utilized in the investigation consist of horizontal global radiation and cloud cover collected for 27 years(1982. 12~2008. 12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is $3.61\;kWh/m^2$ and the annual-average daily cloud cover is 5.1 in Korea. We also constructed the contour map of cloud cover in Korea by interpolating actually measured data across the country.

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.211-217
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• 2018

The Pohang earthquake with a magnitude of 5.4 occurred on November 15, 2018. The epicenter of this earthquake located in south-east region of the Korean peninsula. Since instrumental recording for earthquake ground motions started in Korea, this earthquake caused the largest economic and life losses among past earthquakes. Korea is located in low-to moderate seismic region, so that strong motion records are very limited. Therefore, ground motions recorded during the Pohang earthquake could have valuable geological and seismological information, which are important inputs for seismic design. In this study, ground motions associated by the 2018 Pohang earthquake are generated using the point source model considering domestic geological parameters (magnitude, hypocentral distance, distance-frequency dependent decay parameter, stress drop) and site amplification calculated from ground motion data at each stations. A contour map for peak ground acceleration is constructed for ground motions generated by the Pohang earthquake using the proposed model.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.3
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• pp.242-249
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• 2017

In order to develop an HNS safety management system to assess and visualize hazard levels via an automated method, we have conceptualized and configured a sample system. It is designed to quantify the risk of a vessel carrying HNS with a matrix method along navigational route and indicate hazards distribution with a contour map. The basic system which provides a visualized degree of hazards in real time has been introduced for the safe navigation of HNS ships. This is useful not only for decision making and circumstantial judgment but may also be utilized for HNS safety management with a risk base. Moreover, this system could be extended to address the navigational safety of marine traffic as well as of autonomous vessels in the near future if the sensors used are connected with IoT technology.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.41-44
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• 2010

Hazardous air pollutants such as benzo[a]pyrene (BaP), benzene, formaldehyde have been concerned about the adverse health effect of long-term exposure. Contour map is useful for finding high-concentration region, emission source, and distributions of HAPs in the ambient air. To make a contour map, we have developed simple analytical method for selected HAPs; polycyclic aromatic hydrocarbons such as BaP, benzene and its derivatives such as toluene and xylene, and aldehydes and ketones. We have applied these methods to investigate air pollution by HAPs in some cities in Japan. The results show that these methods reveal actual emission sources if the PRTR emission report was not submitted.