• Journal of Astronomy and Space Sciences
• /
• 제18권1호
• /
• pp.63-70
• /
• 2001

IDGPS(Inverted Differential Global Positioning System)는 GPS의 위치 결정 정밀도를 향상시키는 여러 기법들 중 하나로서 주로 차량 위치 추적이나 물류 시스템에 이용된다. 본 연구에 적용된 IDGPS 기법은 사용자측에서 보내준 GPS 위치해와 위성정보, 그리고 기준국에서 생성된 오차 보정 정보를 이용해 관제국에서 사용자의 위치를 보정하는 것이다. 기준국과 사용자에서 발생한 오차들의 공간적 비상관성(spatial decorrelation)으로 인해 생길 수 있는 정밀도 보정 효과의 저하를 여러 개의 기준국을 이용한 NIDGPS(Network IDGPS)를 통해 해결하였다. 차량항법용 수신기를 사용자 수신기로서 사용하여 실험한 결과, IDGPS와 NIDGPS를 통해 단독 측위에 비해 평균적으로 2배 이상 정밀도가 향상됨을 확인할 수 있었다.

• 한국항해학회지
• /
• 제13권1호
• /
• pp.1-10
• /
• 1989

Nowadays Hyperbolic Navigation System-LORAN, DECCA, OMEGA, OMEGA-is available on the ocean, and Spherical Navigation System, GPS (Global Positioning System) is operated partially. Hyperbolic Navigation System has the blind area near the base line extention because divergence rate of hyperbola is infinite theoretically. The Position Accuracy is differ from the cross angle of LOP although each LOP has the same error of quantity. GDOP(Geometric Dilution of Precisoin) is used to estimate the position accuracy according to the cross angle of LOP and LOP error. Hyperbola and ellipse are crossed at right angle everywhere. Hyperbola and ellipse are used to LOP in Rectangular Navigation System. The equation calculating the GDOP of rectangular Navigation System is induced and GDOP diagram is completed in this paper. A scheme that can improve the position accuracy in the blind area of Hyperboic Navigation System using the Rectangular Navigation System is proposed through the computer simulation.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
• /
• pp.434-434
• /
• 2000

It is the main problem to measure the position and orientation of a robot end effector for the calibration of robots. The calibration methods can be used as a tool to improve the accuracy of robots without change of the arm or control architecture of robots. But such calibration methods require the accurate measurements. Dynamic measurement of position and orientation Provides a solution of this problem and improves dynamic accuracy by dynamic calibration o( robots. This paper describes the development o( the laser tracking system capable of determining the static and dynamic performance of industrial robots. The structure and system components are presented and basic experimental results are included to demonstrate the instrument performance. The system can be applied to the remote controlled mobile robots as weil as the calibration of robots.

• 한국항만학회지
• /
• 제15권1호
• /
• pp.75-85
• /
• 2001

Accuracy of dredging processes depends on the types of equipment used, the sediments encountered, whether the work to be performed is new or maintenance dredging, pre- and post-hydrographic surveying and so forth. Among those, position surveying accuracy which is directly determined by the control of the dredge's position and depth surveying accuracy being surveyed at the dredging point during dredging work are important factors. The purpose of this study is to develop 'Dredge Management System'for Grab dredge which is composed of 4 sub-system using LADGPS for dredge position determining system and dredging point determining system, tide gauge system and optical sensor for depth determining system and GIS and ENC for total management system. This system is installed on the grab dredge 'EUNJIN G-18'and applied to anchorage dredging work. at Pohang Harbor. The results revealed that this system is easy to operate, achieves good accuracy with only 45cm unevenness, reduces working period by 22 percent and saves cost 16.6 percent.

• 한국산학기술학회논문지
• /
• 제14권1호
• /
• pp.94-100
• /
• 2013

본 연구에서는 VRS GNSS(GPS/GLONASS)를 이용하여 지적측량에서의 위치결정 정확도를 분석하여 보고, 이를 토대로 성과결정의 정확도 향상 가능성을 제시하고자 하였다. 연구결과 GPS 위성데이터만을 수신 한 결과 보다 GPS/GLONASS 위성데이터을 통합으로 수신해 위치를 결정한 결과가 대략 3cm 정도 위치정확도가 높은 것으로 분석되었다. 따라서 VRS GNSS 통합 수신 방식이 지적측량에 도입된다면 위치 정확도 향상을 기대할 수 있을 것으로 보인다.

• 한국응급구조학회지
• /
• 제14권1호
• /
• pp.5-18
• /
• 2010

Objective : This study compares Video laryngoscope and Direct laryngoscope in tracheal Intubation on rapidity and accuracy by paramedic and aims to improve efficiency of airway management and survival rate in pre-hospital treatment for the patients with severe trauma, cardiac arrest or dyspnea caused by acute diseases. Methods : 60 paramedics were recruited from 13 fire stations located in C province. With the consent of the paramedics, likelihood ratio test was carried out and they were divided into two different groups; DL group (30) and GVL group (30). Regarding intubation conditions, difficult airway grade I, grade II and grade III as well as sniffing position and neutral position were examined. This study also compared between ambulance in motion and in stand still. Frequency, average and standard deviation were analyzed with statistics program, SPSS WIN 17.0 and repeated measure design was introduced to examine inter-relations between position, grade and groups. Results : Intubation was performed more rapidly in neutral position and GVL than in sniffing position and DL(F = 15.260, p = .000). Rapidity value was better with grade I and grade II than grade III and better with GVL than DL(F = 32.629, p = .000). Accuracy value was higher with neutral position and GVL than sniffing position and DL(F = 5.008, p = .011). grade III was less accurate than grade I, grade II and GVL was more accurate than DL(F = 10.966, p = .000). Ambulance motion status did not show any statistically significant differences in accuracy and rapidity. Conclusion : Given this study results, neutral position is better for the patient with severe trauma. For a better survival, GVL intubation can be considered since GVL can enhance accuracy as well as rapidity regarding difficult airway. Since there is no significant differences in ambulance motion factors, intubation can be recommended even in moving ambulance for shortening traveling time to a hospital.

• Spatial Information Research
• /
• 제9권2호
• /
• pp.263-275
• /
• 2001

NGIS 사업으로 구축된 1/1,000 수치지도의 활용이 급증하면서 이를 활용하기에 앞서 수치지도의 위치정확도 검증이라는 문제가 대두되고 있다. 본 연구에서는 학교 시설물관리시스템 구축에 기반이 되는 소규모 지역에 대한 1/1,000 수치지도의 위치 정확도를 평가하고, 위치오차가 발생한 지역에 대한 수치지도 수정/갱신 방안을 제시하였다. RTK방법으로 교내 주요건물에 대한 위치오차를 평가해 볼 때, 측량관계법령에서 규정하고 있는 0.5mm 보다 크게 나타났다. 이에 대한 위치정확도 확보방안으로 먼저, 교내에 Static 측량을 실시하여 측량기준점을 선정한 후 기준점으로부터 주요건물에 대한 좌표값을 평가하여 RTK 방법으로 측량한 좌표값과 비교하였다. 두 번째로는 지도를 변환하였으며 그 결과를 RTK 측량성과와 비교하였다. 첫 번째 방법과 두 번째 방법을 검토하여 소규모 적합한 수치지도 위치정확도 확보방안을 제시하였다.

• 한국응급구조학회지
• /
• 제23권2호
• /
• pp.99-107
• /
• 2019

Purpose: This study aimed to identify the position for the most accurate head-up cardiopulmonary resuscitation (CPR) by comparing saddle position CPR (SPCPR) and traditional CPR (TCPR). Methods: Sixty certified persons who completed a basic life support provider course between May 1 and June 21, 2019 were enrolled in the study. The participants were asked to perform 2 minutes of CPR, and the depth of chest compression, rate, position, full release, and hands off time were assessed. Accuracy was evaluated based on data collected from a smart phone application connected to the manikin via bluetooth and analyzed using frequency, percentage, t-test, analysis of variance and ${\chi}^2$. Results: The accuracy of chest compression was statistically significantly higher for SPCPR, 63.03%[${\pm}8.75$] for SPCPR and 55.50%[${\pm}10.17$] for TCPR [t=3.074, p=.003]. The depth of chest compression was statistically significantly greater for SPCPR, 4.51cm[${\pm}0.45$] for SPCPR and 4.16cm[${\pm}0.61$] for TCPR [t=2.503, p=.015]. The rate of chest compression was statistically significantly higher for TCPR, 105/min[${\pm}10.79$] for SPCPR and 111/min[${\pm}11.57$] for TCPR [t=-2.008, p=.049]. Accuracy of position of chest compression was statistically significantly higher for SPCPR, 96.10%[${\pm}13.73$] for SPCPR and 79.93%[${\pm}30.34$] for TCPR [t=2.659, p=.011]. Accuracy of full release was higher with SPCPR, with 86.30%[${\pm}30.53$] for SPCPR and 71.10%[${\pm}36.05$] for TCPR, but the difference was not statistically significant [t=1.762, p=.083]. Conclusion: Saddle position CPR was found to be more accurate than TCPR in the performance of manual head-up CPR.

• 센서학회지
• /
• 제28권6호
• /
• pp.414-419
• /
• 2019

An ultrasonic based magnetostrictive position sensor (MPS) provides an indication of real target position. It determines the real target position by multiplying the propagation speed of ultrasonic wave and the time-of-flight between the receiving signals; one is the initial signal by an excitation current and the other is the reflection signal by the ultrasonic wave. The propagation speed of the ultrasonic wave depends on the temperature of the waveguide. Hence, the change of the propagation speed in various environments is a critical factor in terms of the positioning accuracy in the MPS. This means that the influence of the changes in the waveguide temperature needs to be compensated. In this paper, we presents a novel way to improve the positioning accuracy of MPSs using temperature compensation for waveguide. The proposed method used the inherent measurement blind area for the structure of the MPS, which can simultaneously measure the position of the moving target and the temperature of the waveguide without any additional devices. The average positional error was approximately -23.9 mm and -1.9 mm before and after compensation, respectively. It was confirmed that the positioning accuracy was improved by approximately 93%.

• 수산해양기술연구
• /
• 제26권2호
• /
• pp.167-172
• /
• 1990

부산-제주간 선로상에서 정박중일 때와 항행중일 때 Loran C 위치를 관측하여 시간대별, 지역별, 침로별 위치의 정도와 편위오차를 수정하여 분석.검토한 결과는 다음과 같다. 1. 주야간별 위치의 정도는 큰 차이가 없었고, 수신점주위에 높은 산이 있을 경우 편위거리의 오차가 더욱 커졌다. 2. 정박중과 항행중에 편위거리의 평균치는 각각 0.188, 0.452마일이었고, 침로의 변화에 따른 측위오차의 변동은 거의 없었다. 3. 위치정도를 높이기 위해서는 속도보정과 측지계변환만으로도 정도가 높은 위치를 구할 수 있었다