• Proceedings of the KSRS Conference
• /
• v.2
• /
• pp.567-569
• /
• 2006

Recently, the terrestrial laser scanner is considered as useful measurement equipment for acquiring a three-dimensional data. In this study, a terrestrial laser scanner which has +/- 2.5cm accuracy is examined whether the terrestrial laser scanner is reliable to present the tendency of landslide movement. The test area is covered by protection blocks, and they are being moved by landslide movement. Landslide movement was detected by measuring the movement of protection blocks. Totally three scenes of test area were acquired during 2004 and 2006. The three scenes of the protection blocks were registered in global coordinate system, then the landslide movement was investigated. The landslide movement detected in the three scenes was evaluated by comparing with landslide movement measured by a total station. Although the measurement accuracy of landslide using the terrestrial laser scanner was worse than the total station, the scanning data showed the tendency of landslide movement of the test area.

• Journal of the Korean association of regional geographers
• /
• v.3 no.2
• /
• pp.19-35
• /
• 1997

The purpose of this study is to find out the characteristics of landform in Geoje-Do using GIS and DTED data. The characteristics of landform in Geoje-Do are as follows; First, the height-range of Geoje-Do is $0{\sim}580m$, and the average elevation of it is 124m. Volcanic and granite region is mainly appeared at high elevation-region. But, we can't find out outstanding difference of elevation, according to its geology. The second. the slope-range of Geoje-Do is $0{\sim}52$ degree, and the average slope of it is 17.6 degree. The slope of volcanic and granite area is more steeper than any other region. But the results of analysis of the geology in Geojo-Do, don't show outstanding difference of the slope. The third, the area-rate of the aspect of Geoje-Do is almost same in all direction. And the area-rate of south-west direction is the highest. According to the geology of Geoje-Do, granite is distributed the most widely, and the area of volcanic and granite occupy 60% of entire island's area. According to analysis of influence of geology with elevation, geology has little relationship with elevation. According to analysis of geology and drainage network, streams are inclined to be developed well in Alluvium area. Drainage network is well developed throughout the entire island, except southeast area. The highest order of stream is 4 in 1:25,000 topographic map. The density of stream in Geoje-Do is very high, such as 1.6. The bifurcation-ratio of stream is also higher than 4 in all order. The length-ratio of stream is ranged from 1.24 to 3.25. According to the relationship between order and elevation. order is the greater, elevation is the lower. According to the relationship between order and slope, order is the greater, slope is the gentler. In this study, we use DTED Data, and compare it with topographic map data. According to the comparison, there is a little difference between DTED data and topographic map data. Therefore, to use DTED data in landform analysis, it is required coordinate matching process. This process is very important, and take very long time. Thus, if you use DTED in landform analysis, some processes are required. DTED data can be taken very easily, but its using is not simple. Because coordinate adjust is very hard work.

• Proceedings of the Acoustical Society of Korea Conference
• /
• 1998.06c
• /
• pp.323-326
• /
• 1998

The paper describes a theoretical and experimental study on the speed of the torsional elastic waves propagating in an axisymmetirc waveguide whose cross-sectional area varies periodically as an harmonic function of the axial coordinate. The approximate solution of the phase speed has been obtained using the perturbation technique for sinusoidal modulation of small amplitude. The experiment verifying the theoretical result consists of transmitting and receiving torsional waves by magnetostriction and measuring the wave speed in the waveguides with threaded surfaces.

• Journal of Institute of Control, Robotics and Systems
• /
• v.18 no.7
• /
• pp.650-657
• /
• 2012

An effective dual-mode camera system(a passive wide-angle camera and a pan-tilt-zoom camera) is proposed in order to improve the performance of visual surveillance. The fixed wide-angle camera is used to monitor large open areas, but the moving objects on the images are too small to view in detail. And, the PTZ camera is capable of increasing the monitoring area and enhancing the image quality by tracking and zooming in on a specific moving target. However, its FOV (Field of View) is limited when zooming in on a specific target. Therefore, the cooperation of wide-angle and PTZ cameras is complementary. In this paper, we propose an automatic initial set-up algorithm and coordinate transform method from the wide-angle camera coordinate to the PTZ one, which are necessary to achieve the cooperation. The automatic initial set-up algorithm is able to synchronize the views of two cameras. When a moving object appears on the image plane of a wide-angle camera after the initial set-up positioning, the obtained values of the wide-angle camera should be transformed to the PTZ values based on the coordinate transform method. We also develope the PTZ control method. Various in-door and out-door experiments show that the proposed dual-camera system is feasible for the effective visual surveillance.

• The Mathematical Education
• /
• v.45 no.1 s.112
• /
• pp.105-121
• /
• 2006

The purpose of this study is to investigate preservice secondary mathematics teachers' knowledge about graphical representation and provide implications for better mathematics teaching and learning in our schools. For this purpose, sixty-three preservice teachers were selected and given diverse graphical representation problems of y=1, y=x, x=0, $x^2+y^2=1$. All preservice teachers completed two types of questionnaires. First type is about constructing the graphs of the above each equation, and the second one is to make them find the appropriate graphs from given examples of the each equation. The results indicated that all the participant pre service teachers were unable to construct graphs in terms of various dimensions and various direction of coordinate axis. All of the participants represented the graph of each equation on only two-dimensional coordinate system. In addition, some preservice teachers believed that the axis of coordinates have to be x-axis on horizontal line and y-axis on vertical line. From this study, it is implicated that pre service teacher education program needs to provide the experience of representing the graphs of equation in terms of various dimensions and various direction of coordinate axis so as to develop their future students the flexibility and creativity in mathematical thinking especially in the area of space perception.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.29 no.6
• /
• pp.631-639
• /
• 2011

There are problems in using existing fisheries maps, because of deterioration of paper maps, as well as various coordinate systems. In this study, accuracy of fishery maps in World Geodetic System are evaluated. Materials on fishery rights in the Jeollanam-do Province, a study area, used many kind of coordinate systems. During digitization, these coordinate systems have been converted and unified in one World Geodetic System, and one projection origin. In this research, the accuracy of the products of digitization is verified using DGPS surveying. The RMSEs are minimum of 4.62m(at the Younggwang Seas) to maximum of 17.47m(at the Jangheung Seas), and average of 11.97m. The results shows that the digitized fishery maps meet the accuracy standard of 1/25,000 digital topographic maps.

• Journal of Korean Society for Geospatial Information Science
• /
• v.10 no.3 s.21
• /
• pp.53-59
• /
• 2002

Territorial sea baseline is a borderline, with the effectuation of the United Nations Convention on the Law of the Sea of 1982, for the related sea zone negotiations with neighboring countries. Its position must be determined to international standard like WGS84 coordinate system. In this study, GPS survey for territorial sea points was performed to determine territorial baseline around five islands in the yellow sea, and the results of them were compared with previous coordinates. Territorial sea point, outermost spot of a nation's realm, tend to be placed in end up low-tide elevations or precipice. Therefore traditional surveying methods are hard to take accurate observations, so that GPS survey is most effective. Through the study, the scientific and reasonable methods for GPS surveying procedure is presented. The results of coordinate comparison show that there are wide difference between the old and new coordinates, and it is necessary for the whole area of islands to calculate displacements by GPS surveying.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.1197-1199
• /
• 2003

ROCSAT-2 mission is to daily image over Taiwan and the surrounding area for disaster monitoring, land use, and ocean surveillance during the 5-year mission lifetime. The satellite will be launched in December 2003 into its mission orbit, which is selected as a 14 rev/day repetitive Sun-synchronous orbit descending over (120 deg E, 24 deg N) and 9:45 a.m. over the equator with the minimum eccentricity. National Space Program Office (NSPO) is developing a ROCSAT-2 Image Processing System (IPS), which aims to provide real-time high quality image data for ROCSAT-2 mission. A simulated ROCSAT-2 image, based on Level 1B QuickBird Data, is generated for IPS verification. The test image is comprised of one panchromatic data and four multispectral data. The qualification process consists of four procedures: (a) QuickBird image processing, (b) generation of simulated ROCSAT-2 image in Generic Raw Level Data (GERALD) format, (c) ROCSAT-2 image processing, and (d) geometric error analysis. QuickBird standard photogrammetric parameters of a camera that models the imaging and optical system is used to calculate the latitude and longitude of each line and sample. The backward (inverse model) approach is applied to find the relationship between geodetic coordinate system (latitude, longitude) and image coordinate system (line, sample). The bilinear resampling method is used to generate the test image. Ground control points are used to evaluate the error for data processing. The data processing contains various coordinate system transformations using attitude quaternion and orbit elements. Through the qualification test process, it is verified that the IPS is capable of handling high-resolution image data with the accuracy of Level 2 processing within 500 m.

• The Journal of Engineering Geology
• /
• v.33 no.2
• /
• pp.229-240
• /
• 2023

Instruments are installed in soft ground improvement projects to manage economic and safe construction. When analyzing data, the amount of settlement data over time can be used to understand the overall ground settlement behavior, but it is difficult to analyze the interrelatedness between measurement points. Therefore, to analyze the relative compressive settlement behavior between measurement points, the settlement amount and velocity were processed and defined as the mean settlement difference index (AS_i,j) and the slope difference index (SDI_i,j). Plotted in the mean settlement difference index - slope difference index (AS_i,j-SDI_i,j) coordinate system. As a result of the analysis of the relative compaction subsidence behavior between the measuring points, the relationship between the measuring points in the average subsidence difference index - slope difference index coordinate system moved to area 1 as the compaction was completed. By continuously plotting the movement path of the observation point in the corresponding coordinate system, the relative settlement behavior between the measurement points was analyzed, and it was possible to check whether the settlement behavior of the two measurement points was stable or unstable depending on the direction of the path.

• Journal of IKEEE
• /
• v.27 no.4
• /
• pp.486-493
• /
• 2023

In this paper, we propose an automatic hand gesture area extraction and recognition technique using FMCW radar-based point cloud and LSTM. The proposed technique has the following originality compared to existing methods. First, unlike methods that use 2D images as input vectors such as existing range-dopplers, point cloud input vectors in the form of time series are intuitive input data that can recognize movement over time that occurs in front of the radar in the form of a coordinate system. Second, because the size of the input vector is small, the deep learning model used for recognition can also be designed lightly. The implementation process of the proposed technique is as follows. Using the distance, speed, and angle information measured by the FMCW radar, a point cloud containing x, y, z coordinate format and Doppler velocity information is utilized. For the gesture area, the hand gesture area is automatically extracted by identifying the start and end points of the gesture using the Doppler point obtained through speed information. The point cloud in the form of a time series corresponding to the viewpoint of the extracted gesture area is ultimately used for learning and recognition of the LSTM deep learning model used in this paper. To evaluate the objective reliability of the proposed technique, an experiment calculating MAE with other deep learning models and an experiment calculating recognition rate with existing techniques were performed and compared. As a result of the experiment, the MAE value of the time series point cloud input vector + LSTM deep learning model was calculated to be 0.262 and the recognition rate was 97.5%. The lower the MAE and the higher the recognition rate, the better the results, proving the efficiency of the technique proposed in this paper.