• The Korean Journal of Applied Statistics
• /
• v.21 no.4
• /
• pp.695-704
• /
• 2008

The parallel coordinate plot is a graphical data analysis technique for plotting multivariate data. The parallel coordinate plot overcomes the visualization problem of the Cartesian coordinate system for dimensions greater than 4. But, using different ordering of coordinate axes in the parallel coordinate plot of the same data may make different interpretations. Hence, we can use the regular polyprism parallel coordinate plot as an alternative for overcoming the variable arrangement problem of the parallel coordinate plot.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2007.04a
• /
• pp.47-50
• /
• 2007

Since world coordinate system is entirely used because of the revision of land surveying law, it is needed that transformation of coordinates of geo-spatial information established by korea coordinate system to be performed. It is required, however, to have a plan for transformation of world coordinate system because the coordinate system is not unified due to the geo-spatial information system using dualistic control data of both old and new data of korea coordinate system. For this purpose, in this study, I have calculated coordinate transformation coefficient per control data of korea coordinate system and proposed a plan of transforming a dualistic coordinate system which is based on control data of korea coordinate system effectively into world coordinate system through verification of accuracy of transformation per control data.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.8
• /
• pp.1311-1321
• /
• 1997

In multibody dynamics, differential and algebraic equations which can satisfy both equation of motion and kinematic constraint equation should be solved. To solve these equations, coordinate partitioning method and constraint stabilization method are commonly used. In the coordinate partitioning method, the coordinates are divided into independent and dependent and coordinates. The most typical coordinate partitioning method are LU decomposition, QR decomposition, and SVD (singular value decomposition). The objective of this research is to find an efficient coordinate partitioning method in the dynamic analysis of flexible multibody systems. Comparing two coordinate partitioning methods, i.e. LU and QR decomposition in the flexible multibody systems, a new hybrid coordinate partitioning method is suggested for the flexible multibody analysis.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.13 no.3
• /
• pp.44-52
• /
• 2004

This paper proposed a error compensation methodology for three-DOF translational parallel manipulator. The proposed method uses CMM (coordinate measuring machine) as metrology equipment to measure the position of end-effector. To identify the transform relationships between the coordinate system of the parallel manipulator and the CMM coordinate system, a new coordinate referencing (or coordinate system identification) technique is presented. By using this technique, accurate coordinate transformation relationships are efficiently established. According to these coordinate transformation relationships, an equation to calculate the compensating error components at any arbitrary position of the end-effector is derived. In this paper, Monte Carlo simulation method is applied to simulate the compensation process. Through the simulation results, the proposed error compensation method proves its effectiveness and feasibility.

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.11
• /
• pp.99-109
• /
• 2004

This paper proposes precision evaluation method for the positioning error of three-DOF translational parallel mechanism. The proposed method uses conventional CMM as metrology equipment to measure the position of end-effector. In order to obtain accurate measurement data from CMM, the transform relationship between the coordinate system of the parallel mechanism and the CMM coordinate system must be identified. For this purpose, a new coordinate referencing (or coordinate system identification) technique is presented. By using this technique accurate coordinate transformation relationships are efficiently established. According to these coordinate transformation relationships, an equation to calculate error components at any arbitrary position of the end-effector is derived. In addition, mathematical fitting models to represent the position error components in the two-dimensional workspace of the parallel mechanism are also constructed based on response surface methodology. The proposed error evaluation method proves its effectiveness through the experimental results and its application to real three-DOF parallel mechanism.

• Korean Journal of Remote Sensing
• /
• v.8 no.2
• /
• pp.93-104
• /
• 1992

Although the Transverse Mercator(TM) coordinate is used on standard topogrphic maps of Korea as a supplement to regular latitude-longitude coordinate, the use of this TM coordinate system is rather limited to a single coordinate zone that spans only two degrees of longitude. With growing applications of a variety of digiral geographic data, such as satellite remote sensor data, a Cartesian or rectangular coordinate system is more effective to deal with such data type than angular coordinate system. An unified rectangular coordinate system based on the Transverse Mercator projection is designed to cover the whole area of the Korea Peninsula as a single coordinate zone. Considering the width of the peninsula and the distribution of scale error, the origin of the coordinate is determined to 127$^{\circ}$30' east and 38$^{\circ}$ north. Coordinate conversion procedure is discussed along with the corresponding scale error term.

• The Korean Journal of Applied Statistics
• /
• v.21 no.6
• /
• pp.911-921
• /
• 2008

Visualization of the gene expression data on a low-dimensional graph is helpful in uncovering biological information contained in the data. In this study, we focus on two modified versions of the parallel coordinate plot. First one is the ePCP(enhanced parallel coordinate plot) which shows "near smooth" connecting curves between axes spaced proportionately to the proximity of re-ordered variables. Second one is APCP(Andrews' type parallel coordinate plot) which is obtained by rotating Andrews' plot that has a form of the parallel coordinate plot. Visualization procdures using ePCP and APCP are given for the lymphoma data case.

• Aerospace Engineering and Technology
• /
• v.10 no.1
• /
• pp.116-121
• /
• 2011

The tracking radar systems in NARO space center are used in order to acquire the TSPI (Time, Space, and Position Information) data of the launch vehicle. The tracking radar produce the measurements of tracked targets in the radar-centered coordinate system. When the tracking radar is in the Cartesian/Polar tracking mode, the state vector data is sent in radar-centered Cartesian/Polar coordinate system to RCC. RCC also send the slaving data in Test Range coordinate system to the tracking radar. So, the tracking radars have to transform the slaving data in Test Range coordinate system into in radar-centered coordinate system. In this study, we described the coordinate transformation between radar-centered coordinate system and Test Range coordinated system.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.16 no.6 s.111
• /
• pp.643-650
• /
• 2006

This paper is concerned with the vibration analysis of a simply-supported rectangular plate with a circular cutout. Even though there have been many methods developed for the free vibration of the rectangular plate with a rectangular cutout, very few research has been carried out for the rectangular plate with a circular cutout. In this paper, a new methodology called independent coordinate coupling method, which was developed to save the computational effort for the free vibration analysis of rectangular plate with a rectangular cutout, is applied to the case of circular cutout. The independent coordinate coupling method employs the global coordinate system for the plate and the local coordinate system for the cutout. In the case of the rectangular plate with a circular cutout, the global coordinate system is the Cartesian coordinate system and the local coordinate system is the polar coordinate system. By imposing the compatibility condition, the relationship between the global coordinates and the local coordinates is derived. This equation is then used for the calculation of the mass and stiffness matrices resulting in eigenvalue problem. The numerical results show the efficacy of the proposed method.

• Journal of Sensor Science and Technology
• /
• v.28 no.1
• /
• pp.30-35
• /
• 2019

Inertial measurement units (IMUs) are widely used for wearable motion-capturing systems in the fields of biomechanics and robotics. When the IMUs are combined with optical motion sensors (hereafter, OPTs) for their complementary capabilities, it is necessary to align the coordinate system orientations between the IMU and OPT. In this study, we compare the application of two coordinate transformation-based orientation alignment methods between two coordinate systems. The first method (M1) applies angular velocity coordinate transformation, while the other method (M2) applies gyroscopic angle coordinate transformation. In M1 and M2, the angular velocities and angles, respectively, are acquired during random movement for a least-square algorithm to determine the alignment matrix between the two coordinate systems. The performance of each method is evaluated under various conditions according to the type of motion during measurement, number of data points, amount of noise, and the alignment matrix. The results show that M1 is free from drift errors, while drift errors are present in most cases where M2 is applied. Thus, this study indicates that M1 has a far superior performance than M2 for the alignment of IMU and OPT coordinate systems for motion analysis.