• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.4
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• pp.341-353
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• 2022

Pipelines are buried in urban area, and the position (depth and orientation) of buried pipeline should be clearly identified before ground excavation. Although various geophysical methods can be used to detect the buried pipeline, it is not easy to identify the exact information of pipeline due to heterogeneous ground condition. Among various non-destructive geo-exploration methods, ground penetration radar (GPR) can explore the ground subsurface rapidly with relatively low cost compared to other exploration methods. However, the exploration data obtained from GPR requires considerable experiences because interpretation is not intuitive. Recently, researches on automated detection technology for GPR data using deep learning have been conducted. However, the lack of GPR data which is essential for training makes it difficult to build up the reliable detection model. To overcome this problem, we conducted a preliminary study to improve the performance of the detection model using finite difference time domain (FDTD)-based numerical analysis. Firstly, numerical analysis was performed with homogeneous soil media having single permittivity. In case of heterogeneous ground, numerical analysis was performed considering the ground heterogeneity using fractal technique. Secondly, deep learning was carried out using convolutional neural network. Detection Model-A is trained with data set obtained from homogeneous ground. And, detection Model-B is trained with data set obtained from homogeneous ground and heterogeneous ground. As a result, it is found that the detection Model-B which is trained including heterogeneous ground shows better performance than detection Model-A. It indicates the ground heterogeneity should be considered to increase the performance of automated detection model for GPR exploration.

• Journal of the Daesoon Academy of Sciences
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• v.24_2
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• pp.197-229
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• 2015

The aim of this study is to determine the property of Daesoon thought in theory of God. The difference with precedent research is that this study catch the point in which theism as theology conflicts ontology as philosophy. It is elusive without philosophical analysis to detect this point for reasons of religious expression on scriptures. To find this point is beginning of academic communication at religious position. So I tried to draw boundary between theology and philosophy in Daesoon thought so as to apprehend Daesoon thought treats the contradiction of that. The contradiction is found that hierarchy between Sangje and taegeuk reverses on Daesoon thought. Fundamentally two substance can't be arranged to ontology but only one can be. It seems that Daesoon thought has got antinomy. However superiority of Daesoon thought is appeared at this point. The antinomy is just the process to absolute truth of Tao. That is a progressive system of thought in both religious and philosophical aspect. Finally, the result of this study can be organized with five items. First is to get new direction to study of Daesoon thought to catch the clash between theology and ontology. Second is that Daesoon thought can communicate the mainstream philosophy like Hegel's while the argumentation makes progress with Hegel's thought. Third is that Daesoon thought has originality in ontology of tao, mugeuk, tageuk as compared with neo-Confucianism. Forth is that theology of Daesoon thought has the possibility to peace among religions. Fifth is that Daesoon thought transcends religion and philosophy to absolute truth. Particularly, the noteworthy item is about peace among religions as theme of religious practice as the needs of times. The conflict of religion is very serious impact to historic future. So Daesoon thought suggests that all the religions harmonize with each other in universality and respect each other in distinctiveness. It makes it possible to aims for world peace beyond theory to practical orientation on religious creed. In history of philosophy the dialetic of Hegel is the very adequate to explain that principle. Hegel argued that human mind can reach to the absolute knowledge at 『Phänomenologie des Geistes』. He elucidates the process that mind attain the absolute knowledge through movement of negation at 『Phänomenologie des Geistes』. The dialetics leads all the process of mind to finality of the absolute spirit.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.554-560
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• 2020

In the manufacturing process of flat panel displays, a high-precision planar motion stage is used to position a specimen. Stages of this type typically use frictionless linear motors and air bearings, and laser interferometers. Real-time dynamic correction of the yaw motion error is very important because the inevitable yaw motion error of the stage means a change in the specimen orientation. Gantry control is generally used to compensate for yaw motion errors. Flexure units that allow rotational motion are applied to the stage to apply this method to a stage using an air-bearing guide. This paper proposes a method to improve the constant speed motion performance of a H-type XY stage equipped with air bearing and flexure units. When applying the gantry control to the stage, including the flexure units, the cause of the mutual ripple generated from the linear motors is analyzed, and adaptive learning control is proposed to compensate for the mutual ripple. A simulation was performed to verify the proposed method. The speed ripple was reduced to approximately the 22 % level. The ripple reduction was verified by simulating the stage state where yaw motion error occurs.

• Journal of the Korean Ceramic Society
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• v.34 no.2
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• pp.131-138
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• 1997

Silicon carbide films were chemically vapor deposited onto graphite substrates using MTS(Ch3SiCl3) as a source and Ar or H2 as a diluent gas. The experiments were performed at a fixed condition such as a de-position temperature of 130$0^{\circ}C$, a total pressure of 10 torr, and a flow rate of 100 sccm for each MTS and carrier gas. The purpose of this study is to consider the variation of the growth behavior with the addition of each diluent gas. It is shown that the deposition rate leads to maximum value at 200 sccm addition ir-respective of diluent gases and the deposition rate of Ar addition is faster than that of H2 one. It seems that these characteristics of deposition rate are due to varying interrelationship between boundary layer thick-ness and the concentration of a source with each diluent gas addition, when overall deposition rate is con-trolled by mass transport kinetics. The preferred orientation of (220) plane was maintained for the whole range of Ar addition. However, above 200 sccm addition, especially that of (111) plane was more increased in proportion to H2 addition. Surface morphologies of SiC films were the facet structures under Ar addition, but those were gradually changed from facet to smooth structures with H2 addition. Surface roughness be-came higher in Ar, but it became lower in H2 with increasing the amount of diluent gas.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.1
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• pp.67-78
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• 1996

The purpose of this paper is object recognition even in the presence of occlusion by using generalized Hough transform(GHT). The GHT can be considered as a kind of model based object recognition algorithm and is executed in the following two stages. The first stage is to store the information of the model in the form of R-table (Reference table). The next stage is to identify the existence of the objects in the image by using the R-table. The improved GHT method is proposed for the practical vision system. First, in constructing the R-table, we extracted the partial arc from the portion of the whole object boundary, and this partial arc can be used for constructing the R-table. Also, clustering algorithm is employed for compensating an error arised by digitizing an object image. Second, an efficient method is introduced to avoid Ballard's use of 4-D array which is necessary for estimating position, orientation and scale change of an object. Only 2-D array is enough for recognizing an object. Especially, scale token method is introduced for calculating the scale change which is easily affected by camera zoom. The results of our test show that the improved hierarchical GHT method operates stably in the realistic vision situation, even in the case of object occlusion.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.123-133
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• 2011

In this paper, we propose a new method for toon shading using 3D texture which renders 3d objects in a cartoon style. The conventional toon shading using 1D texture displays shading tone by computing the relative position and orientation between a light vector and surface normal. The 1D texture alone has limits to express the various tone change according to any viewing condition. Therefore Barla et. al. replaces a 1D texture with a 2D texture whose the second dimension corresponds to the view-dependent effects such as level-of-abstraction, depthof-field. The proposed scheme extends 2D texture to 3D texture by adding one dimension with the geometric information of 3D objects such as curvature, saliency, and coordinates. This approach supports two kinds of extensions for cartoon style diversification. First, we support "shape exaggeration effect" to emphasize silhouette or highlight according to the geometric information of 3D objects. Second, we further incorporate "cartoon specific effect", which is examples of screen tone and out focusing frequently appeared in cartoons. We demonstrate the effectiveness of our approach through examples that include a number of 3d objects rendered in various cartoon style.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.2
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• pp.203-211
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• 2009

With supply of the domestic digital camera, the relative importance of the digital camera is coming to be high gradually on aerial photogrammetry, the image of digital camera is more applied in image map or digital topographic map production. But, there are cases that do not have position information or attitude information of each photograph in digital camera results. Therefore, we wish to present additional method to get more accurate photograph control point result. In this study, One is called A method, which is the case of entering positioning information of principal point from topographic map as default values that are need to extract tie point automatically using by 56 pieces of photography that are photographed by DMC to the extent to 5 courses and 35 GCP points. The other is called B-method, which is the case of entering exterior orientation parameters that are processed by block adjustment for A-method using by 4 control points in method-1 as default values. We have analyzed about results per control points arrangement for two cases using MATCH-AT that is photograph control point measurement S/W of Germany INPHO company. As a result of analysis, accuracy of B-method was better than that of A-method, and we could get more accurate results if block adjustments are executed including self calibration. Also, it is more effective in expense side that using self calibration for photograph survey in B-method because can reduce GCP numbers.

• Knowledge Management Research
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• v.24 no.3
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• pp.17-34
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• 2023

Recently, national concern for record breaking level of deficit operation of KEPCO grows bigger in Korea. With this regard, many stakeholders believe KEPCO should be responsible for this result although it is not clear whether KEPCO is only to blame who is in such position where full cost pricing is impossible and entrepreneurial efficiency is not guaranteed. Particularly, less concern is given to Performance Evaluation for Public Organization(PEPO) which did not give prior warning against major deficit of KEPCO or help to improve its capacity to deal with the problem, and thus prevented KEPCO from acknowledging its managerial weakness by crediting KEPCO with successive grade B during the period of previous government. Based on such viewpoint, this study analyzes reports of PEPO for 5 years in terms of evaluability assessment and suggests proper direction for better PEPO in the future. From this analysis, it was found that firstly, relevant suggestion was not made to prevent or improve defict problem; secondly, comments are increasing every year without consistency; thirdly, comments related to long-term investment are only recently found; fourthly, suggestions are based on political orientation rather than evidence or expertise. This study is expected to contribute to evidence-based evaluation and knowledge management since it tackles evaluation reports themselves for the first time.

• Korean Journal of Remote Sensing
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• v.29 no.2
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• pp.183-195
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• 2013

Real-time high-precision image georeferencing is important for the realization of image based precise navigation or sophisticated augmented reality. In general, high-precision image georeferencing can be achieved using the conventional simultaneous bundle adjustment algorithm, which can be performed only as post-processing due to its processing time. The recently proposed sequential bundle adjustment algorithm can rapidly produce the results of the similar accuracy and thus opens a possibility of real-time processing. However, since the processing time still increases linearly according to the number of images, if the number of images are too large, its real-time processing is not guaranteed. Based on this algorithm, we propose a modified fast algorithm, the processing time of which is maintained within a limit regardless of the number of images. Since the proposed algorithm considers only the existing images of high correlation with the newly acquired image, it can not only maintain the processing time but also produce accurate results. We applied the proposed algorithm to the images acquired with 1Hz. It is found that the processing time is about 0.02 seconds at the acquisition time of each image in average and the accuracy is about ${\pm}5$ cm on the ground point coordinates in comparison with the results of the conventional simultaneous bundle adjustment algorithm. If this algorithm is converged with a fast image matching algorithm of high reliability, it enables high precision real-time georeferencing of the moving images acquired from a smartphone or UAV by complementing the performance of position and attitude sensors mounted together.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.3
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• pp.305-313
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• 2014

Purpose: A correlation between the rotating direction and rotation amount according to the eccentricity was analyzed in the present study when fitting the toric soft contact lens. Methods: One hundred fourteen eyes of with-the-rule astigmatism in 20s and 30s were appropriately applied toric soft contact lens by the guideline of manufacturer and fitting evaluations and analyzed the rotating direction and rotation amount when fixating at primary position and 8 different directions of gaze. The speed of reorientation and the correlation between the rotation amount and cornea eccentricity were also analyzed when rotating $45^{\circ}$ each toward the temporal and nasal direction. Results: The cornea eccentricity and rotation amount was shown positive correlation. For the gaze of direction, it was identified that the gaze of directions other than the gaze of direction towards the nasal and temporal had correlation, and among them, the gaze of directions to superior and the superior-temporal showed the tendency of decreasing rotation amount as the cornea eccentricity increased. On the contrary, the gaze of direction towards the inferior, inferior-temporal, superior-nasal, and inferior-nasal showed tendency of increasing rotation amount as the cornea eccentricity increased thus, it was identified that the cornea eccentricity showed different correlation according to the gaze of direction. For the case of re-orientational speed, the speed of lens reorientation in the group having the smallest corneal eccentricity was fastest in both direction but was not significantly different. Conclusions: Considering cornea eccentricity to current method of prescribing toric soft contact lens which is based on total astigmatism, it will be helpful to establish the optimal axis stabilization.