• Journal of the Korea Institute of Military Science and Technology
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• 제12권1호
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• pp.80-87
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• 2009

The purpose of this study is to analyze the MAUP's effect in visibility analysis using GIS. MAUP normally occurs in the process in terrain spatial analysis including visibility analysis. There are two different types of grid data(based on digital map and Digital Terrain Elevation Data) and 10 different types of areal units are made for modeling, such as $5m{\times}5m,\;10m{\times}10m,\;15m{\times}15m,\;20m{\times}20m,\;25m{\times}25m,\;30m{\times}30m,\;35m{\times}35m,\;40m{\times}40m,\;45m{\times}45m,\;50m{\times}50$. By analyzing the result, it was possible to observe varying viewshed areas according to different grid cell sizes and the viewshed area did not varied linearly as expected. From a general point of view, smaller unit data map out the real world in more detail, but the results of modeling do not always reach a good conclusion when data are used in modeling for terrain analysis because of the MAUP' effect. The grid cell sizes of 30m or less seems to be adequate for visibility analysis, including terrain analysis considering vegetation heights.

• Journal of Practical Engineering Education
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• 제7권2호
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• pp.97-105
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• 2015

In this paper, we have selected physical computing as the focused learning elements with the PBL-based programming instruction method. Students experienced physical computing by using Arduino. Development of robot using Arduino can create an effective educational environment and also provide solutions for lack of environmental conditions, such as time or spatial factor restrictions and excessive expense issues; these are major obstacles to developing robot programming education. Finally, we analyzed the effects on growth of student's logical thinking and problem solving abilities by demonstrating the Arduino application courseware to the field of education.

• Steel and Composite Structures
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• 제34권1호
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• pp.75-89
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• 2020

The current paper illustrates the effect of in-plane varying compressive force on critical buckling loads and buckling modes of sandwich composite laminated beam rested on elastic foundation. To generalize a proposed model, unified higher order shear deformation beam theories are exploited through analysis; those satisfy the parabolic variation of shear across the thickness. Therefore, there is no need for shear correction factor. Winkler and Pasternak elastic foundations are presented to consider the effect of any elastic medium surrounding beam structure. The Hamilton's principle is proposed to derive the equilibrium equations of unified sandwich composite laminated beams. Differential quadrature numerical method (DQNM) is used to discretize the differential equilibrium equations in spatial direction. After that, eigenvalue problem is solved to obtain the buckling loads and associated mode shapes. The proposed model is validated with previous published works and good matching is observed. The numerical results are carried out to show effects of axial load functions, lamination thicknesses, orthotropy and elastic foundation constants on the buckling loads and mode shapes of sandwich composite beam. This model is important in designing of aircrafts and ships when non-uniform compressive load and shear loading is dominated.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• 제19권4호
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• pp.562-569
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• 2010

This paper analyzes the problems that occurred in the magnification process for a fine input image and investigates a method to improve the blurring of magnified image. This paper applies a curve interpolation algorithm in CAD/CAM for the same test images with the existing image algorithm in order to improve the blurring of magnified image. As a result, the nearest neighbor interpolation, which is the most frequently applied algorithm for the existing image interpolation algorithm, shows that the identification of a magnified image is not possible. Therefore, this study examines an interpolation of gray-level data by applying a low-pass spatial filter and verifies that a bilinear interpolation presents a lack of property that accentuates the boundary of the image where the image is largely changed. The periodic B-spline interpolation algorithm used for curve interpolation in CAD/CAM can remove the blurring but shows a problem of obscuration, and the Ferguson' curve interpolation algorithm shows a more sharpened image than that of the periodic B-spline algorithm. For the future study, hereafter, this study will develop an interpolation algorithm that has an excellent improvement for the boundary of the image and continuous and flexible property by using the NURBS, Ferguson' complex surface, and Bezier surface used in CAD/CAM engineering based on the results of this study.

• Journal of Institute of Control, Robotics and Systems
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• 제9권8호
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• pp.585-591
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• 2003

A virtual force is generated and fed back to the operator to make the teleoperation more reliable, which reflects the relationship between a slave robot and an uncertain remote environment as a form of an impedance. In general, for the teleoperation, the teleoperated mobile robot takes pictures of the remote environment and sends the visual information back to the operator over the Internet. Because of the limitations of communication bandwidth and narrow view-angles of camera, it is not possible to watch certain regions, for examples, the shadow and curved areas. To overcome this problem, a virtual force is generated according to both the distance between the obstacle and the robot and the approaching velocity of the obstacle w.r.t the collision vector based on the ultrasonic sensor data. This virtual force is transferred back to the master (two degrees of freedom joystick) over the Internet to enable a human operator to estimate the position of obstacle at the remote site. By holding this master, in spite of limited visual information, the operator can feel the spatial sense against the remote environment. It is demonstrated by experiments that this collision vector based haptic reflection improves the performance of teleoperated mobile robot significantly.

• The Journal of the Acoustical Society of Korea
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• 제31권5호
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• pp.332-339
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• 2012

Beamspace transform algorithm transforms spatial-domain data - such as x, y, z dimension - into incidence-angle-domain data, which is called beamspace-domain data. The beamspace transform method is generally used in source localization and tracking, and adaptive beamforming problem. When the beamspace transform method is used in multichannel audio source separation, the inverse beamspace transform is also important because the source image have to be reconstructed. This paper studies the beamspace transform and inverse transform algorithms for multichannel audio source separation system, especially for the beamspace-domain multichannel NMF algorithm.

• Nuclear Engineering and Technology
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• 제25권1호
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• pp.20-27
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• 1993

This paper concerns with developing a simplified in-core fuel management scoping tool for PWR. For this purpose the point reactivity model is put into a fuel cycling decision code, FCYPRM. Modified Borresen's coarse-mesh diffusion theory and nodal expansion method are utilized to form a spatial neutron analysis code, CMSNAP. Numerical experiments are per- formed to determine a set of empirical shuffling rules for working out an automated fuel loading pattern search code, ALPS. The numerical examples are presented for verifying effectiveness and applicability of individual codes. By structuring and applying three codes for reload core design problem of a PWR, it is demonstrated that these codes provide an effective in-core fuel management scoping tool for PWR.

• Journal of the Korea Society of Computer and Information
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• 제21권6호
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• pp.21-28
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• 2016

Circle detection has long been studied as one of fundamental image processing applications. It is used in divers areas including industrial inspection, medial image analysis, radio astronomy data analysis, and other object recognition applications. The most widely used class of circle detection techniques is the circle Hough transform and its variants. Management of 3 dimensional parameter histogram used in these methods brings about spatial and temporal overheads, and a lot of studies have dealt the problem. This paper proposes a robust circle detection method using maximal symmetry property of circle. The basic idea is that if perpendicular bisectors of pairs of edges are accumulated in image space, center of circle is determined to be the location of highest accumulation. However, directly implementing the idea in image space requires a lot of calculations. The method of this paper reduces the number of calculations by mapping the perpendicular bisectors into parameter space, selecting small number of parameters, and mapping them inversely into image space. Test on 22 images shows the calculations of the proposed method is 0.056% calculations of the basic idea. The test images include simple circles, multiple circles with various sizes, concentric circles, and partially occluded circles. The proposed method detected circles in various situations successfully.

• The Journal of Korean Academy of Prosthodontics
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• 제44권2호
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• pp.243-249
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• 2006

Statement of problem: It is important to have a correct presurgical treatment plan before any implant surgery. It must contain substantial information about the patient concerned. However, the standard classification only notifies the dentist about various structural, pathological and physiological dimensions Due to diverse structure of the jaw bone, current standard classification does not tell spatial dimensions of the available bone for implant insertion sites. Purpose of study: The purpose of this study is to report the establishment of the systematic implant treatment plan and its clinical treatment using $Implan^(R)$ program which is based on ASCIi-classification that is available for future diagnosis and scale of treatment and for systematic implant insertion. Results: By assisting the systemic measurement of the available alveolus dimension during implant surgery, it was easy to set initial implant treatment plan. Conclusion: Using $Implan^(R)$ program which is based on ASCIi-classification system that allows the establishment of systemic implant treatment plan and successful clinical performance, it was possible to establish the founding or initial implant treatment plan , the acquisition of information, and the systematization of documentation.

• Korean Institute of Interior Design Journal
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• 제39호
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• pp.83-91
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• 2003

The planning of circulation area and circulation path are very important elements for layout of interior space of housing. This study is, therefore, aimed at synthetical review of that area from a functional, structural and socio-cultural point of view as well as typological analysis of that area. In the interior space of housing the networking of spaces according to the circulation route imply divers aspects of independent or dependant significances. It is thus, closely related with to whether circulation area open or closed, whether circulation path concentrated or distributed, and whether it passes Individual rooms or not. With regard to relationship with public and private spaces, there are many grounds for combining each other. This study also tried to develope program for planning of circulation system, utilizing typological analysis of them. At the same time this study suggests examples for layout of housing spaces. It is expected that the results represented In the form of systematic diagram will deserve to be a tool for providing an appropriate solution to the problem of diversity of user's needs.