• 한국통신학회논문지
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• 제28권6C호
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• pp.561-569
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• 2003

본 논문에서는 Alamouti［1］, Tarokh［14］, Xia［11］에 의해 도입된 직교 시공간 부호를 포함한 임의의 선형 직교 시공간 블록 부호에 대해, 느린 레일라이 페이딩 채널(slow Rayleigh fading channel)의 쌍간 오율(pairwise error probability)의 정확한 표현이 2개의 전송된 부호어 행렬(codeword matrices) 사이의 부호어 심볼 거리(codeword symbol distance)가 아니라, 2개의 메시지 벡터(messgae vector) 사이의 메시지 심볼 거리(message symbol distance)의 식으로 유도된다. 1차원 성분의 심볼 오율을 이용하여, 선형 직교 시공간 부호의 심볼 오율의 정확한 폐형의 표현이 QPSK, 16-QAM, 64-QAM과 256-QAM에 대해 유도된다.

• 한국산업융합학회 논문집
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• 제24권6_2호
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• pp.753-762
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• 2021

Google provides mapping services using satellite imagery, this is widely used for the study. Since about 20 years ago, research and business using drones have been expanding. Pix4D is widely used to create 3D information models using drones. This study compared the distance error by comparing the result of the road construction site with the DSM data of Google Earth and Pix4 D. Through this, we tried to understand the reliability of the result of distance measurement in Google Earth. A DTM result of 3.08 cm/pixel was obtained as a result of matching with 49666 key points for each image. The length and altitude of Pix4D and Google Earth were measured and compared using the obtained PCD. As a result, the average error of the distance based on the data of Pix4D was measured to be 0.68 m, confirming that the error was relatively small. As a result of measuring the altitude of Google Earth and Pix4D and comparing them, it was confirmed that the maximum error was 83.214m, which was measured using satellite images, but the error was quite large and there was inaccuracy. Through this, it was confirmed that there are difficulties in analyzing and acquiring data at road construction sites using Google Earth, and the result was obtained that point cloud data using drones is necessary.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권2호
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• pp.960-973
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• 2018

This paper presents design for error correcting algorithm of the time of flight (ToF) detection value in the light detection and ranging (LIDAR) system sensor. The walk error of ToF value is generated by change of the received signal power depending on distance between the LIDAR sensor and object. The proposed method efficiently compensates the ToF value error by the independent ToF value calculation from the received signal using both rising point and falling point. A constant error of ~0.05 m is obtained after the walk error correction while an increasing error up to ~1 m is obtained with conventional method.

• 대한인간공학회지
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• 제30권1호
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• pp.109-115
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• 2011

In this research, three topics were studied for the elderly. The first was the elderly's error characteristics for tracing task and the second was for depth perception. The characteristics were compared with the young's. Twenty two old people and twenty two young people participated in the tracing experiment, respectively. In the depth perception experiment, twenty three old people and twenty two young people participated. A depth perception apparatus and a tracing one were used in the experiment. In the depth perception error, a significant difference was not detected on gender. However significant differences were detected with age and viewing distance. In the tracing error, significant difference was detected with age, also. The third experiment was push-button operation and fifteen old people participated in the experiment. As the result, operation time error was increased with the button size and the moving distance. The result of this study will be able to be considered in its user interface design to reduce the elderly's error while using a product.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.625-627
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• 2005

Existent distance measurement that use camera is method that use both Stereo Camera and Monocular Camera, There is shortcoming that method that use Stereo Camera is sensitive in effect of a lot of expenses and environment variables, and method that use Monocular Camera are big computational complexity and error. In this study, reduce expense and error using Monocular Camera and I suggest algorithm that measure distance, Extract features using scale Invariant features Transform(SIFT) for distance measurement, and this measures distance through features matching and geometrical analysis, Proposed method proves measuring distance with wall by geometrical analysis free wall through feature point abstraction and matching.

• 로봇학회논문지
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• 제7권1호
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• pp.45-56
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• 2012

This paper proposes how to improve the performance of CSS-based indoor localization system. CSS based localization utilizes signal flight time between anchors and tag to estimate distance. From the distances, the 3-dimensional position is calculated through trilateration. However the error in distance caused from multi-path effect transfers to the position error especially in indoor environment. This paper handles a problem of reducing error in raw distance information. And, we propose the new localization method by pattern matching instead of the conventional localization method based on trilateration that is affected heavily on multi-path error. The pattern matching method estimates the position by using the fact that the measured data of near positions possesses a high similarity. In order to gain better performance of localization, we use EKF(Extended Kalman Filter) to fuse the result of CSS based localization and robot model.

• 한국측량학회지
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• 제9권1호
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• pp.55-61
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• 1991

수평각 관측에 있어서 관측값에 미치는 영향은 우연오차인 시준오차 및 읽기오차 뿐만 아니라 구심오차도 이에 수반된다. 따라서 본 연구에서는 위의 오차중 구심오차가 관측값에 미치는 영향을 검토하기 위하여 구심오차의 이론식 및 평가식을 유도하고 이를 이용 관찰 시험관측을 통하여 고찰해보았다. 본 연구결과 구심오차는 시준거리, 관측각, 편심거리 및 편심각을 알므로서 산출되고, 3배각수로 관측함이 오차가 작아 실용적이며, 또한 기기의 성능에 따라 시준거리 및 관측각을 이용하여 그 평가가 가능하다.

• 한국정보전자통신기술학회논문지
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• 제3권1호
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• pp.53-56
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• 2010

본 논문은 운송 안전 환경에서 멀티미디어 원격 제어를 위한 소프트웨어 오류를 감지하기에 적합한 에이전트이다. 이 시스템은 ED, ES로 구성되어 있다. ED는 IP-USN 게이트웨이 소프트웨어 스택 환경에서 멀티미디어 원격 제어를 위하여 훅 킹 기법으로 오류를 감지하는 에이전트이다. ES는 IP-USN 게이트웨이 소프트웨어 스택 환경에서 멀티미디어 원격 제어를 위하여 오류를 공유하는 에이전트이다. 멀티미디어 공동 작업 환경의 관점에서 오류 공유는 협동 작업에 참가하는 참가자에게 상호작용적으로 오류를 공유한다.

• 제어로봇시스템학회논문지
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• 제17권9호
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• pp.947-953
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• 2011

Radome aberration error causes degradation of miss distance as well as stability of high maneuver missile system with RF seeker. A study about radome compensation method is important in this kind of missile system design. Several kinds of methods showed good compensation performance in their paper. Proposed adaptive Particle filter estimates line of sight rate excluding the radome induced error. This paper shows effectiveness of adaptive Particle filter as compensation method of radome aberration error. Robust performance of this filter depends on external aiding measurement, target acceleration. Tuning of system error covariance can make this filter unsensitive against the error of target acceleration information. This paper demonstrates practical usage of adaptive Particle filter for reducing miss distance and increasing stability against disturbance of radome aberration error through performance analysis.

• 한국군사과학기술학회지
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• 제8권3호
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• pp.56-63
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• 2005

The radome boresight error degrades the microwave seeker ability and the missile guidance performance. It increases the miss distance, also. This paper propose a method of radome boresight error measurement and compensation. The compensation method consist of radome analysis and radome compensation. In the radome analysis stage, we can know that the electromagnetic characteristics distorted by radome. In the compensation stage, the look-up table is built and used for compensation. The test uses a FMS(Flight motion simulator) and adjusts the FMS setup error for more accuracy. The result shows that not using an elaborate radome measurement equipment, the radome boresight error is well compensated easily.