• Title/Summary/Keyword: Mapping error

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Correction and Positioning of Remote Sensing Image Base on Orbit Parameter

  • Cheng, Chunquan;Zhang, Jixian;Yan, Qin;Wang, Yali
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1212-1214
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    • 2003
  • The usual technique of correction and positioning of film image of RS require enough control points to provide the geographic coordinate. Some distortion and error caused by earth curvature and terrain and photograph tilt can't be eliminated by these ways. In this paper a set of technique of systemic correction and positioning of remote sensing image base on orbit parameter is described, some questions in its realization and their solvent also included.

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Omni-directional Visual-LiDAR SLAM for Multi-Camera System (다중 카메라 시스템을 위한 전방위 Visual-LiDAR SLAM)

  • Javed, Zeeshan;Kim, Gon-Woo
    • The Journal of Korea Robotics Society
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    • v.17 no.3
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    • pp.353-358
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    • 2022
  • Due to the limited field of view of the pinhole camera, there is a lack of stability and accuracy in camera pose estimation applications such as visual SLAM. Nowadays, multiple-camera setups and large field of cameras are used to solve such issues. However, a multiple-camera system increases the computation complexity of the algorithm. Therefore, in multiple camera-assisted visual simultaneous localization and mapping (vSLAM) the multi-view tracking algorithm is proposed that can be used to balance the budget of the features in tracking and local mapping. The proposed algorithm is based on PanoSLAM architecture with a panoramic camera model. To avoid the scale issue 3D LiDAR is fused with omnidirectional camera setup. The depth is directly estimated from 3D LiDAR and the remaining features are triangulated from pose information. To validate the method, we collected a dataset from the outdoor environment and performed extensive experiments. The accuracy was measured by the absolute trajectory error which shows comparable robustness in various environments.

A STUDY ON THE EFFECTIVE ALGORITHMS BASED ON THE WEGMANN'S METHOD

  • Song, Eun-Jee
    • Journal of applied mathematics & informatics
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    • v.20 no.1_2
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    • pp.595-602
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    • 2006
  • Determinations of conformal map from the unit disk onto a Jordan region are reduced to solve the Theodorsen equation which is an integral equation for the boundary correspondence function. Among numerical conformal maps the Wegmann's method is well known as a Newton efficient one for solving Theodorsen equation. However this method has not so wide class of convergence. We proposed as an improved method for convergence by applying a low frequency filter to the Wegmann's method. In this paper, we investigate error analysis and propose an automatic algorithm based on this analysis.

Noor Iterations with Error for Non-Lipschitzian Mappings in Banach Spaces

  • Plubtieng, Somyot;Wangkeeree, Rabian
    • Kyungpook Mathematical Journal
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    • v.46 no.2
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    • pp.201-209
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    • 2006
  • Suppose C is a nonempty closed convex subset of a real uniformly convex Banach space X. Let T : $C{\rightarrow}C$ be an asymptotically nonexpansive in the intermediate sense mapping. In this paper we introduced the three-step iterative sequence for such map with error members. Moreover, we prove that, if T is completely continuous then the our iterative sequence converges strongly to a fixed point of T.

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The Pilot Production of Topographic-Cadastral Maps and Its Applications in Korea

  • Park, Yun-Soo;Park, Byung-Uk
    • Korean Journal of Geomatics
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    • v.1 no.1
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    • pp.51-59
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    • 2001
  • The Government confirmed the action planning of digital mapping project for major thematic maps based on ‘Revised Plan for The Development of the National Geographic Information System’(NGIS). Mapping for major thematic maps was begun in 1998 when digital mapping project for topographic maps finished due to the delay of the action planning, and will selectively have produced the essential digital thematic maps according to the frequency of usage. The models of topographic-cadastral maps and administrative boundary maps around Suwon were produced in accordance with the presented draft. We presented specification for production of the most appropriate topographic-cadastral maps and administrative boundary maps through the analysis of the process of production, discussion and error check, and correction of the produced topographic-cadastral maps and administrative boundary maps. And we could make it easier to develop digital mapping project of topographic-cadastral maps and administrative boundary maps effectively by presenting the strategy for data input and maintenance, the cost model for carrying out the digital thematic map production, digital topographic maps, and the supplement of data model and data format. Topographic-cadastral maps has a wide range of usage but a lot of difficulties in the process of production and map update under use. So it seems that the study on users, university, private sector and municipal self-government must follow for promoting the use of topographic-cadastral maps.

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An Efficient Constellation Rearrangement for HARQ with 64QAM (64QAM 변조 방식의 HARQ 전송을 위한 효율적인 성상 재배열 방법)

  • Park, Won-Seok;Cho, Chung-Ki;Kim, Jong-Hwan;Kim, Sang-Hyo
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.6
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    • pp.14-21
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    • 2011
  • In this paper, we propose an efficient symbol mapping method based on LLR (log-likelihood ratio) statistic for HARQ employing CoRe (constellation rearrangement) with 64QAM. The signal constellations for 64QAM with limited number of retransmissions are selected by the proposed mapping rule. Then we determine the transmission order of selected constellations. The proposed scheme reduces the performance deviation between transmit symbols so as to improve the system performance. Through simulation results, the proposed and existing CoRe mapping methods are compared with respect to error rate and throughput in MIMO-OFDM system over fading channel and we confirm the applicability of the proposed scheme in practical wireless communications environment.

Mobile Robot Localization and Mapping using a Gaussian Sum Filter

  • Kwok, Ngai Ming;Ha, Quang Phuc;Huang, Shoudong;Dissanayake, Gamini;Fang, Gu
    • International Journal of Control, Automation, and Systems
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    • v.5 no.3
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    • pp.251-268
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    • 2007
  • A Gaussian sum filter (GSF) is proposed in this paper on simultaneous localization and mapping (SLAM) for mobile robot navigation. In particular, the SLAM problem is tackled here for cases when only bearing measurements are available. Within the stochastic mapping framework using an extended Kalman filter (EKF), a Gaussian probability density function (pdf) is assumed to describe the range-and-bearing sensor noise. In the case of a bearing-only sensor, a sum of weighted Gaussians is used to represent the non-Gaussian robot-landmark range uncertainty, resulting in a bank of EKFs for estimation of the robot and landmark locations. In our approach, the Gaussian parameters are designed on the basis of minimizing the representation error. The computational complexity of the GSF is reduced by applying the sequential probability ratio test (SPRT) to remove under-performing EKFs. Extensive experimental results are included to demonstrate the effectiveness and efficiency of the proposed techniques.

Simultaneous Localization and Mapping For Swarm Robot (군집 로봇의 동시적 위치 추정 및 지도 작성)

  • Mun, Hyun-Su;Shin, Sang-Geun;Joo, Young-Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.3
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    • pp.296-301
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    • 2011
  • This paper deals with the simultaneous localization and mapping system using cooperative robot. For recognizing environment, swarm robot uses the ultrasonic sensors and vision sensor. Ultrasonic sensors measure the distance information, and vision sensor recognizes the predefined landmark. we used SURF with excellent quality and fast matching in order to recognize landmark. Due to measurement error of sensors, we fusion them using particle filter for accurate localization and mapping. Finally, we show the feasibility of the proposed method through some experiments.

ANN Synthesis Models Trained with Modified GA-LM Algorithm for ACPWs with Conductor Backing and Substrate Overlaying

  • Wang, Zhongbao;Fang, Shaojun;Fu, Shiqiang
    • ETRI Journal
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    • v.34 no.5
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    • pp.696-705
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    • 2012
  • Accurate synthesis models based on artificial neural networks (ANNs) are proposed to directly obtain the physical dimensions of an asymmetric coplanar waveguide with conductor backing and substrate overlaying (ACPWCBSO). First, the ACPWCBSO is analyzed with the conformal mapping technique (CMT) to obtain the training data. Then, a modified genetic-algorithm-Levenberg-Marquardt (GA-LM) algorithm is adopted to train ANNs. In the algorithm, the maximal relative error (MRE) is used as the fitness function of the chromosomes to guarantee that the MRE is small, while the mean square error is used as the error function in LM training to ensure that the average relative error is small. The MRE of ANNs trained with the modified GA-LM algorithm is less than 8.1%, which is smaller than those trained with the existing GA-LM algorithm and the LM algorithm (greater than 15%). Lastly, the ANN synthesis models are validated by the CMT analysis, electromagnetic simulation, and measurements.

A Method for Considering Performance Shaping Factors in Quantitative Human Error Analysis (정량적 인적오류 분석에서 수행도형성인자를 고려하기 위한 방법)

  • 정광태
    • Journal of the Korean Society of Safety
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    • v.12 no.1
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    • pp.113-121
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    • 1997
  • Human reliability attempts to make precise quantitative analyses and predictions of the performance of human-machine(or product) systems. In order to yield more precise human error analysis, precise human error probabilities(HEPs) must be used in the analysis. However, because human behavior is influenced by factors that are called performance shaping factors(PSFs), the effects of PSFs must be considered to obtain precise HEPs, These are called basic HEPs or situation-specific HEPs. This paper presents a theoretical method for obtaining basic HEPs (i.e. , considering PSFs) in quantitative human error analysis. In this method, the weight which characterizes the degree of importance of several PSFs is obtained by the analytic hierarchy process. The quality scores of PSFs in the task situation are obtained by percentile concept. These scores are used in conjunction with the relative Importance weights of PSFs to compute the composite quality percentile score of PSFs in the task situation. Then, a new mapping method of the composite quality percentile score of PSFs into a situation-specific basic HEP is proposed with a numerical example.

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