• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.23 no.2
• /
• pp.101-108
• /
• 2005

Inertial Navigation System has been used extensively to determine the position, velocity and attitude of the body. An INS is very expensive, however, heavy, power intensive, requires long setting times and the accuracy of the system is degraded as time passed due to the accumulated error. Global Positioning System(GPS) receivers can compensate for the Inertial Navigation System with the ability to provide both absolute position and attitude. This study describes a method to improve both the accuracy of a body positioning and the precision of an attitude determination using GPS antenna array. Existing attitude determination methods using low-cost GPS receivers focused on the relative vectors between the master and the slave antennas. Then the positioning of the master antenna is determined in meter-level because the single point positioning with pseudorange measurements is used. To obtain a better positioning accuracy of the body in this research, a wireless internet is used as an alternative data link for the real-time differential corrections and dual-frequency GPS receivers which is expected to be inexpensive was used. The numerical results show that this system has the centimeter level accuracy in positioning and the degree level accuracy in attitude.

• Aerospace Engineering and Technology
• /
• v.11 no.2
• /
• pp.80-86
• /
• 2012

A fast maneuvering LEO satellite producing high resolution images was developed by Korea Aerospace Research Institute and launched successfully. To achieve accurate pointing and stringent pointing stability, the attitude orbit control subsystem implements high performance star trackers and gyroscopes. In addition, series of on-orbit calibration need to be performed to compensate mainly misalignment errors due to launch shock and on-orbit thermal environment. In this paper, the on-orbit calibration approach is described with the performance enhancement result through flight data analysis.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.11 no.5
• /
• pp.145-150
• /
• 2011

This study was developed the posture balance system of multi-parameter for moving body after and before exercising. Body transition meaned a head moving and upper body moving. This system has catched a signal for physical condition of body data such as a data acquisition system, data signal processing and feedback system. There were checked a parameter that measured vision, vestibular, somatosensory, CNS. This system was evaluated a data through the stability. The posture balance system can be used to support assessment for body moving in exercising situation. It was expected to monitor a physical parameter for health management system.

• The Bulletin of The Korean Astronomical Society
• /
• v.37 no.2
• /
• pp.166.2-166.2
• /
• 2012

국내에서 개발한 고기동 저궤도 위성이 일본 다네가시마 우주센터에서 2012년 5월 18일 발사되었다. 자세제어계는 위성의 임무수행을 완수할 수 있도록 발사 후부터 위성 수명 기간 동안 자세명령을 생성하고 제어 및 결정을 하며, 궤도 조정과 모멘텀 덤핑등의 임무를 수행한다. 이러한 임무 수행을 가능하게 하기 위해 자세제어계는 적절한 센서와 구동기 조합을 사용하여 추력기 기반 안전모드, 궤도 조정을 위한 Del-V Burn 기동 모드, 태양지향 서브모드 및 목표지향 서브모드 등을 설계했다. 고기동 위성의 초기 운용 중 자세제어계는 자세제어계 하드웨어의 초기 구동 및 점검을 수행하고 설계한 각 모드의 기능과 성능 확인을 수행하게 된다. 본 연구는 성공적으로 완료한 자세제어계 하드웨어의 초기 점검 결과를 소개하는 것이 목적이다. 초기 운용은 위성이 발사된 직후 탑재컴퓨터가 깨어나면서부터 시작되는데, 발사 후 최초 접속시 추력기 기반 안전모드에서 태양 획득 성능 및 제어 성능을 확인한 후 정상 상태 모드인 태양지향 자세로 전환하기 위해 자세제어계 하드웨어인 별 추적기, 자기토커, 반작용휠의 초기 구동 및 점검을 수행하였다. 본 연구에서는 각 하드웨어의 초기 구동 점검과 성능 및 기능 요구조건 만족에 대한 성능 분석 결과를 정리하였다.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.12 no.3
• /
• pp.229-234
• /
• 2008

Hepatobiliary scintigraphy is very sensitivity of hepatic cell and gallbladder, biliary track atresia and biliary leakage. however, Hepatobiliary scan of biliary leakage diagnosis was separated determine biliary leakage and bowl drainage bile-juice. The object of this study will determine biliary leakage and bowl drainage bile-juice to hepatobiliary scintigraphy both decubitus position in bile leakage patients. Material & Methode: 31 patients (meal 14, Femeal 17), $51.1{\pm}14.4$ years. dynamic scan acquisition 60 farme for 60 minute on supine position. and delay scan was 2 hrs, 4 hrs, 24 hrs for 5 minute on supine, both decubitus position. Both decubitus position scan was kept for 5 minutes. Efficient of Hepatobiliary Scintigraphy both decubitus position in bile leakage patients was compared leakage size, density, image of supine position and both decubitus position. Results: 23 patients for 31 bile leakage patients was checked up function image or delay image, and 8 patients was checked up bile leakage on both decubitus. anatomical leakage location was supine position very well, but both decubitus position was separated bile leakage and moving bile-juice in bowl. also, uptake (counts/pixel) average of roi and bkg was supine 5.02, left decubitus 2.08, right decubitus 2.68. No. pixels of supine ROI counted 1.91 times than left decubitus, 1.05 times than right decubitus. Conclusion: 31 patient both decubitus position, but decubitus position was separated bile juice movement in bowl leakage location. also, It was compared ROI/BKG ratio and ROI No. pixels of supine, both decubitus in 38.5% patients. And No. pixels of supine position was large 19%, 5% than left decubitus, right decubitus, And density was in low 60%, 50% than left decubitus, right decubitus. It was mean bile leakage of ROI. so, If Hepatobiliary Scintigraphy was additional both decubitus position scan in bile leakage patients, this study will be more valuable in diagnosis of bile leakage.

• KIPS Transactions on Software and Data Engineering
• /
• v.8 no.11
• /
• pp.457-464
• /
• 2019

The weight of pig is one of the main factors in determining the health and growth state of pigs, their shipment, the breeding environment, and the ration of feed, and thus measuring the pig's weight is an important issue in productivity perspective. In order to estimate the pig's weight by using the number of pig's pixels from images, acquired from a Top-view camera, the posture determining and the head removal from images are necessary to measure the accurate number of pixels. In this research, we propose the fast and accurate method to determine the pig's posture by using a fast image processing technique, find the head location by using a fast deep learning technique, and remove pig's head by using light weighted image processing technique. First, we determine the pig's posture by comparing the length from the center of the pig's body to the outline of the pig in the binary image. Then, we train the location of pig's head, body, and hip in images using YOLO(one of the fast deep learning based object detector), and then we obtain the location of pig's head and remove an outside area of head by using head location. Finally, we find the boundary of head and body by using Convex-hull, and we remove pig's head. In the Experiment result, we confirmed that the pig's posture was determined with an accuracy of 0.98 and a processing speed of 250.00fps, and the pig's head was removed with an accuracy of 0.96 and a processing speed of 48.97fps.

• KIPS Transactions on Software and Data Engineering
• /
• v.11 no.10
• /
• pp.409-418
• /
• 2022

In this paper, we propose SAAnnot-C3Pap, a semi-automatic annotation method for obtaining ground truth of a player's posture. In order to obtain ground truth about the two-dimensional joint position in the existing music domain, openpose, a two-dimensional posture estimation method, was used or manually labeled. However, automatic annotation methods such as the existing openpose have the disadvantages of showing inaccurate results even though they are fast. Therefore, this paper proposes SAAnnot-C3Pap, a semi-automated annotation method that is a compromise between the two. The proposed approach consists of three main steps: extracting postures using openpose, correcting the parts with errors among the extracted parts using supervisely, and then analyzing the results of openpose and supervisely. Perform the synchronization process. Through the proposed method, it was possible to correct the incorrect 2D joint position detection result that occurred in the openpose, solve the problem of detecting two or more people, and obtain the ground truth in the playing posture. In the experiment, we compare and analyze the results of the semi-automated annotation method openpose and the SAAnnot-C3Pap proposed in this paper. As a result of comparison, the proposed method showed improvement of posture information incorrectly collected through openpose.

• Aerospace Engineering and Technology
• /
• v.4 no.1
• /
• pp.114-121
• /
• 2005

다목적실용위성 2호 영상의 geo-location 정밀도 80 m (CE90) 요구사항을 만족시키기 위하여, 1개의 IRU 와 2개의 star tracker 들로부터 획득되는 데이터를 이용하여 지상에서 후처리 추정 과정을 거쳐 위성의 자세를 결정하는 정밀자세결정 시스템이 개발되었다. 정밀자세결정 시스템의 정밀도를 극대화하기 위해서는 우주 공간의 극심한 열적 환경으로 인해 발생하는 star tracker 정렬 오차를 효율적으로 보정하여야 한다. 정밀한 정렬 오차의 보정을 위해서는 영상 내에 촬영된 지상의 ground control point 데이터를 이용하여야 하는데, 현실적으로 한반도 모든 지역에 대해 ground control point 를 확보할 수 없다. 현재 항공우주연구원이 확보하고 있거나 이후 확보할 예정에 있는 고해상도 영상을 위한 ground control point 들은 대전지역에 국한될 예정이다. 이와 같은 상황에서 정밀자세결정 시스템의 성능을 높이기 위한 최적의 시스템 운용 개념을 본 연구에서 제시하였으며, 시뮬레이션을 통해 그 타당성을 분석하였다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2017.04a
• /
• pp.1129-1130
• /
• 2017

본 연구에서는 현대인들의 하루 중 많은 시간을 차지하는 착좌 생활을 관리하기 위한 롤러블(rollable) 스마트패드를 개발하였다. 이를 위해 PVDF(polyvinylidene fluoride) 필름을 이용한 압전센서(piezoelectric sensor)를 제작하였으며, 센서에서 데이터를 획득하고 및 햅틱 피드백(haptic feedback)을 주기 위한 측정시스템을 개발하였다. 또한, 스마트폰 어플리케이션을 통해 착좌 자세에 대한 정보를 실시간으로 제공하도록 하였다. 제작된 시스템의 착좌 자세 구분 정확도는 10명의 피험자를 대상으로 평가되었으며, 4가지 자세(상체를 좌, 우, 앞, 뒤로 기울인 앉은 자세)에 대한 실험결과 제작된 시스템은 92.5%의 정확도로 제시한 4가지의 자세를 구분하였다.

• Current Industrial and Technological Trends in Aerospace
• /
• v.7 no.2
• /
• pp.121-130
• /
• 2009

In this paper, the attitude and orbit control subsystem technology of new GEO communication and observation satellite using Sun sensors are introduced and analyzed. COMS is new GEO communication and Earth observation satellite based on EUROSTAR 3000 space bus technology. The attitude and orbit control subsystem of COMS adopts a configuration using three BASS and three LIASS Sun sensors to acquire the attitude error information in the specific reference frames. These Sun sensors are used to acquire Sun direction and to control the spacecraft to keep the relative attitude with respect to a reference Sun direction in both transfer and operational orbits. In this paper, the mathematical models of BASS and LIASS are described as well as their operational implementation in the flight software.