• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2010.04a
• /
• pp.341-345
• /
• 2010

It is known that the accuracy of DEM is related with terrain morphology, sampling density, and interpolation method. However, the theoretical reasons for these correlations have rarely been accounted for so far. This study aimed to verify a theoretical basis that DEM accuracy can be assessed based on approximation theory when we generate a DEM using lots of precise and accurate source data such as digital maps and LIDAR data.

• Proceedings of the KIPE Conference
• /
• 2018.07a
• /
• pp.308-309
• /
• 2018

This paper proposes new D/A(Digital to Analog) Design method for improving accuracy in high-performance test equipment. The proposed new D/A design can improve accuracy of the equipment even with low-resolution D/A converters. The validity of proposed D/A design is verified by analysis and experiment.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2007.04a
• /
• pp.231-235
• /
• 2007

As the centralization of city, underground facilities is increasing and being more important. And there were many underground facilities accidents in korea. It is very important to update and to have high quality accuracy of underground facilities maps. But the underground facilities maps are mapped and updated by each institutes. So it is difficult to verify the accuracy of the data. In this study, To analyze the accuracy of maps, Surveying of undergroud facilities for 18 GUs in Seoul is performed during 3 years using Electromegnetic Induction Method, Total Station and GPS. In conclusion, Horizontal accuracy of 6 underground facilities management institutes is 73cm(2004), 78cm(2005) and 75cm(2006).

• Journal of Institute of Control, Robotics and Systems
• /
• v.5 no.1
• /
• pp.88-94
• /
• 1999

This paper presents an accuracy evaluation method for muzzle velocity measurement systems. Among various measuring techniques, the solenoid coil scheme and the doppler radar scheme are considered due to their popularity in applications. The error sources are first identified and their effects on the accuracy of the measuring systems are quantified using mathmatical equations. The theoritic accuracy limits are then verified through comparison with experimental results. From the accuracy point of view, they turn out to be standard velocity measuring systems.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.10 no.5
• /
• pp.26-30
• /
• 2011

Currently, many researches are carried out about tilting index table, which is one of the main component of 5-axis machine tool. The performance of the tilting index table is associated the rotational accuracy which is very important factor for high precision machining because it have an effect on machining error. In this paper, a tilting index table is developed, and the rotational accuracy of the tilting index table using a laser measurement equipment is measured. In addition, a correction value is obtained from the measured value through compensation, and the correction value is used to improve the accuracy of the table. Comparative analysis is carried out for the accuracy of the table before and after compensation. This paper can be used by a reference for performance and reliability advancement of tilting index table.

• Journal of Korean Society for Geospatial Information Science
• /
• v.15 no.4
• /
• pp.111-116
• /
• 2007

This study is aimed to analyze the accuracy of depth information of reservoir using the robot-ship equipped with GPS and echosounder. The accuracy of depth measurements by sounding data was analyzed according to change of robot-ship's speed in the water. The field experiment results showed that as robot-ship's speeds were slow, accuracy of sounding data were increased. Until Robot-ship's speed was up to 5 km/hr, the accuracy of sounding data were included reliable section of normal distribution.

• Journal of the Korean Institute of Navigation
• /
• v.22 no.1
• /
• pp.1-13
• /
• 1998

Radiobeacons that carry corrections for global satellite navigation systems are currently being planned or installed in many countries. In early 1996, it was begun to send DGPS correction message from a marine radiobeacon station located in Changgi Got Lighthouse. It was the first test broadcast of DGPS correction data based on medium frequency of marine radiobeacon where transmission power and rate are 300W and 100bps respectively in Korea. However, there has not been any scientific study on the characteristic of the accuracy of a marine radiobeacon/DGPS. Accordingly, this paper investigates the accuracy of the system, which is currently operating in 310kHz. To do this , the real time differential correction in RTCM data was collected in an implemented system. And then the accuracy was analyzed related to the coverge of the radiobeacon/DGPS. As a result, it is verified that the differential positioning accuracy using the marine radiobeacon is sufficient to ensure the safety of marine activities around the coast of Korea.

• Journal of Advanced Marine Engineering and Technology
• /
• v.20 no.4
• /
• pp.90-100
• /
• 1996

To maintain high spacial accuracy and rapid CPU time in interpolating data from grid to random position or inversely in PIV, proposed many technuques are compared and discussed mainly in terms of interpolating error and computing time. And artificial PIV atmosphere data is furnished by CFD result. First, for interpolation from grid to random position, multiquadric method gives the highest accuracy with the longest CPU time and Taylor series expansion methods give reasonable accuracy with less calculating load. Secondly, the sub-pixel resolution analysis in estimating the coordinates of the maximum correlation coefficients essential in the grey level correlation PIV reveal that 8-neighbours 2nd-order least square interpolation gives utmost accuracy in terms of the real flow conditions.

• Journal of Advanced Marine Engineering and Technology
• /
• v.20 no.4
• /
• pp.412-412
• /
• 1996

To maintain high spacial accuracy and rapid CPU time in interpolating data from grid to random position or inversely in PIV, proposed many technuques are compared and discussed mainly in terms of interpolating error and computing time. And artificial PIV atmosphere data is furnished by CFD result. First, for interpolation from grid to random position, multiquadric method gives the highest accuracy with the longest CPU time and Taylor series expansion methods give reasonable accuracy with less calculating load. Secondly, the sub-pixel resolution analysis in estimating the coordinates of the maximum correlation coefficients essential in the grey level correlation PIV reveal that 8-neighbours 2nd-order least square interpolation gives utmost accuracy in terms of the real flow conditions.

• International Journal of Internet, Broadcasting and Communication
• /
• v.13 no.2
• /
• pp.208-217
• /
• 2021

3D-CNN is one of the deep learning techniques for learning time series data. However, these three-dimensional learning can generate many parameters, requiring high performance or having a significant impact on learning speed. We will use these 3D-CNNs to learn hand gesture and find the parameters that showed the highest accuracy, and then analyze how the accuracy of 3D-CNN varies through input data changes without any structural changes in 3D-CNN. First, choose the interval of the input data. This adjusts the ratio of the stop interval to the gesture interval. Secondly, the corresponding interframe mean value is obtained by measuring and normalizing the similarity of images through interclass 2D cross correlation analysis. This experiment demonstrates that changes in input data affect learning accuracy without structural changes in 3D-CNN. In this paper, we proposed two methods for changing input data. Experimental results show that input data can affect the accuracy of the model.