• Journal of IKEEE
• /
• v.15 no.1
• /
• pp.10-14
• /
• 2011

In this paper, we present an efficient hardware architecture of unrolling image mapper of catadioptric omnidirectional imaging systems. The catadioptric omnidirectional imaging systems generate images of 360 degrees of view and need to be transformed into panorama images in rectangular coordinate. In most application, it has to perform the panorama unrolling in real-time and at low-cost, especially for high-resolution images. The proposed hardware architecture adopts a software/hardware cooperative structure and employs several optimization schemes using look-up-table(LUT) of coordinate conversion. To avoid the on-line division operation caused by the coordinate transformation algorithm, the proposed architecture has the LUT which has pre-computed division factors. And then, the amount of memory used by the LUT is reduced to 1/4 by using symmetrical characteristic compared with the conventional architecture. Experimental results show that the proposed hardware architecture achieves an effective real-time performance and lower implementation cost, and it can be applied to other kinds of catadioptric omnidirectional imaging systems.

• Journal of Astronomy and Space Sciences
• /
• v.16 no.2
• /
• pp.159-166
• /
• 1999

As the spatial resolution of remote sensing satellites becomes higher, very accurate determination of the position of a LEO (Low Earth Orbit) satellite is demanding more than ever. Non-symmetric Earth gravity is the major perturbation force to LEO satellites. Since the orbit propagation is performed in the celestial frame while Earth gravity is defined in the terrestrial frame, it is required to convert the coordinates of the satellite from one to the other accurately. Unless the coordinate conversion between the two frames is performed accurately the orbit propagation calculates incorrect Earth gravitational force at a specific time instant, and hence, causes errors in orbit prediction. The coordinate conversion between the two frames involves precession, nutation, Earth rotation and polar motion. Among these factors, unpredictability and uncertainty of Earth rotation, called UTI-UTC, is the largest error source. In this paper, the effect of UTI-UTC on the accuracy of the LEO propagation is introduced, tested and analzed. Considering the maximum unpredictability of UTI-UTC, 0.9 seconds, the meaningful order of non-spherical Earth harmonic functions is derived.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2009.04a
• /
• pp.11-13
• /
• 2009

This research is renewal way to get latest digital map, We presented techniques to convert to GIS data for update digital map to utilize completion drawing of CAD data that is used construction and SOC construction. Conversion process is consisted of layer extraction, object transform, coordinate transform, format transform. GIS data that is changed via each process from CAD data can update digital map.

• Proceedings of the IEEK Conference
• /
• 2002.06d
• /
• pp.279-282
• /
• 2002

This Paper of use vision system, there is no DGPS's information, DGPS data value receives real time exactly without being influenced in surroundings environment because using vision system that is used in self-regulation traveling by car system. Therefore, conversion and DGPS of received in camera coordinate changing coordinate error correct and wish to grasp correctly position of vehicles.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.7
• /
• pp.1646-1652
• /
• 2015

In this paper, we propose a depth conversion method for orthoscopic real image reconstruction in integral imaging. Pseudoscopic image has been regarded a problem in conventional integral imaging. the depth of reconstructed image is depending on a coordinate of an elemental image. The conversion from pseudoscopic to orthoscopic may be possible by analysing the geometrical relation between pickup and reconstruction system of elemental image. The feasibility of the proposed method has been confirmed through preliminary experiments as well as ray optical analysis.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11a
• /
• pp.306-309
• /
• 2005

This parer describes the tracking control simulation of 6-DOF shaking table with a bell crank structure, which converts the direction of reciprocating movements. For the Joint coordinate-based control which uses lengths of each actuator, the trajectory conversion process inverse kinematics is performed. Applying the Newton-Euler approach, the dynamic equation of the shaking table is derived. To cope with nonlinear problems, time-delay control(TDC) is considered, which has been noted for its exceptional robustness to parameter uncertainties and disturbance, in addition to steady-state accuracy and computational efficiency. If the nominal model is equal to the real system, joint coordinate-based control can be very efficient. However, manufacturing tolerances installation errors and link offsets contaminate the nominal values of the kinematic parameters used in the kinematic model of the shaking table. To compensate differences between the nominal model and the real system. the joint coordinate-based control using acceleration feedback in the Cartesian coordinate space is proposed.

• Journal of Advanced Navigation Technology
• /
• v.17 no.3
• /
• pp.271-278
• /
• 2013

In this paper, ECEF to ECI coordinate transformation algorithm which uses EOP parameters in GPS civil navigation message is introduced, and ECEF to ECI coordinate transformation simulation results were analyzed. The ECEF to ECI coordinate transformation includes GPS to UTC, and UTC to other types of time conversions and EOP data processing algorithms. The ECEF to ECI coordinate conversion algorithm was certified using real LEO satellite position, velocity GPS data, and EOP data which offered by the Earth Orientation Center.

• Geophysics and Geophysical Exploration
• /
• v.19 no.4
• /
• pp.236-248
• /
• 2016

In this review, the basic concepts of geodetic coordinate system and map projection are explained to practitioners in exploration geophysicists to enhance the understanding of geographic and projected coordinate system. The fundamental elements such as earth ellipsoid, geoid, geocentric and geodetic latitudes, rhumb line, and great circle are dealt with in detail. The geocentric and geodetic coordinate systems are also summarized neatly, together with coordinate conversion formulae. In addition, the concept and technique for datum transforms between local and world datum are presented, with special emphasis on Korean Geodetic System.

• Journal of the Economic Geographical Society of Korea
• /
• v.10 no.2
• /
• pp.167-181
• /
• 2007

The newly adopted Korea Geodetic Datum (a.k.a. KGD2002) calls for massive reengineering work on geospatial dataset. The main focus of our study is placed on the strategy and system implementations of the required data reengineering with a keen attention to integrated approaches to interoperability, standardization, and database utilization. Our reengineering strategy includes file-to-file, file-to-DB, DB-to-file, and DB-to-DB conversion for the coordinate transformation of KGD2002. In addition to the map formats of existing standards such as DXF and Shapefile, the newly recommended standards such as GML and SVG are also accommodated in our reengineering environment. These four types of standard format may be imported into and exported from spatial database via KGD2002 transformation component. The DB-to-DB conversion, in particular, includes not only intra-database conversion but also inter-database conversion between SDE/Oracle and Oracle Spatial. All these implementations were carried out in multiple computing environments: desktop and the Web. The feasibility test of our system shows that the coordinate differences between Bessel and GRS80 ellipsoid agree with the criteria presented in the existing researches.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.10
• /
• pp.2443-2450
• /
• 2014

In the motion recognition system using depth image, the depth image is converted to the real world formed 3D point cloud data for efficient algorithm apply. And then, output depth image is converted by the projective world after algorithm apply. However, when coordinate conversion, rounding error and data loss by applied algorithm are occurred. In this paper, when convert 3D point cloud data to depth image, we proposed efficient conversion method and its hardware implementation without rounding error and data loss according image size change. The proposed system make progress using the OpenCV and the window program, and we test a system using the Kinect in real time. In addition, designed using Verilog-HDL and verified through the Zynq-7000 FPGA Board of Xilinx.