• 응용통계연구
• /
• 제21권4호
• /
• pp.695-704
• /
• 2008

평행좌표그림은 다변량자료를 시각화하는 하나의 방법이다. 평행좌표그림은 4차원 이상의 직각좌표계 표시의 어려움을 극복할 수 있는 그림이다. 그러나 변수 축의 배열에 따라 같은 자료에 대하여도 다른 해석이 가능하다. 변수 선택 문제를 해결하는 한 가지 방법으로서 우리는 정다각기둥평행좌표그림을 제안할 수 있다.

• 한국측량학회:학술대회논문집
• /
• 한국측량학회 2007년도 춘계학술발표회 논문집
• /
• 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.

• 대한기계학회논문집A
• /
• 제21권8호
• /
• 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.

• 한국공작기계학회논문집
• /
• 제13권3호
• /
• 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.

• 한국정밀공학회지
• /
• 제21권11호
• /
• 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.

• 대한원격탐사학회지
• /
• 제8권2호
• /
• pp.93-104
• /
• 1992

현재 한국표준지형도에서 사용되고 있는 횡단메카토르좌표(TM) 체제는 한반도 전체를 단일의 직각좌표 체계로 표시하는데 제한이 있다. 인공위성 원격탐사 및 지리정보 시스템의 광범 위한 응용과 함께, 직각좌표체계가 종래의 경위도좌표체계보다 이용에 있어서 보다 편리하고 효 과적이라 할 수 있다. 본 논문에서는 한반도 전체를 하나의 좌표구역으로 포함하는 통합된 직각 좌표체계를 제안함으로써 표준직각좌표체계 설정의 기반을 도모하고자 하였다. 표준지형도 제작 에 사용된 횡단메카토르 투영법을 그대로 유지하고, 기존의 TM좌표 및 UTM좌표를 약간 변형하 여 기준원점이 동경 127$^{\circ}$30'와 북위 38$^{\circ}$가 되는 직각좌표체계를 시도하였다. 경위도 좌표 에서 통합된 직각좌표로의 변환과정을 축척오차의 분포 문제와 함께 기술하였다.

• 응용통계연구
• /
• 제21권6호
• /
• pp.911-921
• /
• 2008

유전자발현 자료로터 유용한 생물학적 정보를 얻기 위해 여러 시각화 방법이 개발되어 왔다. 본 논문에서는 평행좌표 플롯(parallel coordinate plot: PCP)을 이용하여 유전자발현 패턴을 찾아내어 표현하고자 하였다. 평행좌표 플롯의 두 변형인 ePCP(enhanced parallel coordinate plot)와 APCP(Andrews' type parallel coordinate plot)를 림포마(lymphoma) 자료에 적용하여 62개 샘플을 의미있게 배열하고 300개 유전자를 평활 곡선으로 표현하였다.

• 항공우주기술
• /
• 제10권1호
• /
• pp.116-121
• /
• 2011

나로우주센터 추적레이더가 획득한 실시간 위치 정보는 발사통제시스템에서 위치, 속도, 비행궤도 표시, 예상궤도 진입여부 및 안전을 위한 비행종료시점 판단 등의 중요한 데이터로 사용된다. 추적레이더에서 발사통제시스템으로 전송하는 표적의 위치 정보는 추적레이더 중심의 좌표값 데이터이며, 발사통제시스템에서 추적레이더로 전송하는 Slaving 데이터는 발사대 중심의 좌표값 데이터이다. 이렇듯 추적레이더와 발사통제시스템 간의 송수신 데이터는 각 시스템에 맞게 적절하게 좌표 변환이 수행되어야 한다. 본 연구에서는 나로우주센터 추적레이더 간의 상호 데이터 송수신 및 발사통제시스템과의 데이터 통신에 사용되는 각각의 좌표계 및 좌표계 간의 좌표 변환에 대해 기술하였다.

• 한국소음진동공학회논문집
• /
• 제16권6호
• /
• 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.

• 센서학회지
• /
• 제28권1호
• /
• 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.