• Title/Summary/Keyword: Real number system

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LiDAR based Real-time Ground Segmentation Algorithm for Autonomous Driving (자율주행을 위한 라이다 기반의 실시간 그라운드 세그멘테이션 알고리즘)

  • Lee, Ayoung;Yi, Kyongsu
    • Journal of Auto-vehicle Safety Association
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    • v.14 no.2
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    • pp.51-56
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    • 2022
  • This paper presents an Ground Segmentation algorithm to eliminate unnecessary Lidar Point Cloud Data (PCD) in an autonomous driving system. We consider Random Sample Consensus (Ransac) Algorithm to process lidar ground data. Ransac designates inlier and outlier to erase ground point cloud and classified PCD into two parts. Test results show removal of PCD from ground area by distinguishing inlier and outlier. The paper validates ground rejection algorithm in real time calculating the number of objects recognized by ground data compared to lidar raw data and ground segmented data based on the z-axis. Ground Segmentation is simulated by Robot Operating System (ROS) and an analysis of autonomous driving data is constructed by Matlab. The proposed algorithm can enhance performance of autonomous driving as misrecognizing circumstances are reduced.

The Effect of Real-time Traffic Information System Relieving Traffic Congestion

  • Kang, Ho Jun;Moon, Tae Nam;Lee, Kang Hyeok;Song, Young Do;Shin, Do Hyoung
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.652-653
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    • 2015
  • This study investigates the effect of real-time traffic information on the traffic flows in Korea. Recently, the development of smartphones has made it easier to use the route guidance service based on real-time traffic information. By the Big Data analysis in the study, it was found that the number of postings on the web community sites increased sharply in 2010 and 2011 when the smartphones spread widely. In the analysis of the traffic speeds by time, the average traffic speeds for morning and evening rush hours on weekdays from 2009 to 2014 of the 142 sections in the 6 national highways in Gyeonggi-do, Korea were used. From the results of the analysis, it was found that the percentage of the number of sections with the improved traffic flows increased greatly in 2012 compared to 2011. The findings of the study indicate the effect of the real-time traffic information on improving traffic flows.

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Contents Delivery Service System in Internet-based P2P Computing (인터넷기반 P2P 컴퓨팅 환경에서의 콘텐츠 전송 서비스 시스템에 관한 연구)

  • Kim, Jin-Il
    • Journal of Internet Computing and Services
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    • v.6 no.6
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    • pp.1-12
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    • 2005
  • The number of web contents is enormous in the billions and rapidly growing, Most contents are state, but an increasing number are generated dynamically, Therefore, Internet-based client/server architecture of Contents Delivery Service System suffers from frequent disconnections and security threats casused by dependency of the server or overload. Idle computing resources in Internet are used for sloving these issues, In this paper, We implement and design the Content Delivery Service System for cyber education system using idle Computing Power in P2P computing to share computing resources, We implement not only internet infrastructure but also satellite infrastructure system. and designed to transfer real-time or non real-time contents.

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Moving-Target Tracking System Using Neural Networks (신경회로망을 이용한 이동 표적 추적 시스템)

  • 이진호;윤상로;이승현;허선종;김은수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.11
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    • pp.1201-1209
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    • 1991
  • Generally, the conventional tracking algorithms are very limited in the practical applications because of its exponential increase in the required computation time for the number of targets being tracked. Therefore, in this paper, a new real-time moving target tracking system is proposed, which is based on the neural networks with massive parallel processing capabilities. Through the theoretical and experimental results, the target tracking system based on neural network algorithm is analyzed to be computationally independent of the number of objects being tracked and performs the optimized tracking through its massive parallel computation and learning capabilities. And this system also has massive matched filtering effects because the moving target data can be compactly stored in the interconnection weights by learning. Accordingly, a possibility of the proposed neural network target tracking system can be suggested to the fields of real-time application.

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Rainfall Estimation for Hydrologic Applications (수문학적 응용을 위한 강우량 산정)

  • 배덕효
    • Water for future
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    • v.28 no.1
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    • pp.133-144
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    • 1995
  • The subject of the paper is the selection of the number and location of rainguage stations among existing ones, which will be part of real-time data collection system, for the computation of mean areal precipitation and for use as input of real-time flow forecasting models. The weighted average method developed by National Weather Service was used to compute MAP. Two different searching methods were used to find local optimal solutions as a function of the number of rainguages. An operational rainfall-runoff model was used to determine the optimal location and number of stations for flow prediction.

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On the performance of improved quadrature spatial modulation

  • Holoubi, Tasnim;Murtala, Sheriff;Muchena, Nishal;Mohaisen, Manar
    • ETRI Journal
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    • v.42 no.4
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    • pp.562-574
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    • 2020
  • Quadrature spatial modulation (QSM) utilizes the in-phase and quadrature spatial dimensions to transmit the real and imaginary parts of a single signal symbol, respectively. The improved QSM (IQSM) transmits two signal symbols per channel use through a combination of two antennas for each of the real and imaginary parts. The main contributions of this study can be summarized as follows. First, we derive an upper bound for the error performance of the IQSM. We then design constellation sets that minimize the error performance of the IQSM for several system configurations. Second, we propose a double QSM (DQSM) that transmits the real and imaginary parts of two signal symbols through any available transmit antennas. Finally, we propose a parallel IQSM (PIQSM) that splits the antenna set into equal subsets and performs IQSM within each subset using the same two signal symbols. Simulation results demonstrate that the proposed constellations significantly outperform conventional constellations. Additionally, DQSM and PIQSM provide a performance similar to that of IQSM while requiring a smaller number of transmit antennas and outperform IQSM with the same number of transmit antennas.

Alternative Tracing Method for Moving Object Using Reference Template in Real-time Image - Focusing on Parking Management System (참조 템플릿 기반 실시간 이동체 영상을 이용한 대안적 탐지 방안 - 주차관리시스템을 대상으로)

  • Joo, Yong Jin;Kang, Lee Seul;Hahm, Chang Hahk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.5
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    • pp.495-503
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    • 2014
  • As the number of vehicles has been sharply increases, the significance of safety and effective operation issues in the parking lot is being emphasized, which takes a part of the transportation system. Recently, there have been several studies for the parking management by detecting moving object, however, recognizing numbers of fast-moving vehicles simultaneously in the picture is still a challenging problem. The parking lot in public area, or large-sized buildings has clear parking section, whereas the sensor system is configured to monitor a plurality of parking spaces. Therefore, by considering those parking lots, we suggested to develop the real-time parking availability information system by applying the real-time image processing techniques. with the help of template matching. Following the study, we wanted to provide the alternative method for parking management system through the reference template makers by recognizing movements of parked vehicles with the size and shape, regardless of direct detecting of driving movements. In addition, we evaluated the applicability and performances of the information system, presented in this study, and implemented a prototype system to simulate the parking statuses of each floor. In fat, it was possible to manage and analyze statistics about the total number of parking spaces and the number of vehicles parked through real-time video flames. We expected that the result of the study will be advanced, following the user-friendliness and cost reduction in operating parking management system and giving information by efficient analysis of parking situation.

Design and Implementation of a Lightweight On-Device AI-Based Real-time Fault Diagnosis System using Continual Learning (연속학습을 활용한 경량 온-디바이스 AI 기반 실시간 기계 결함 진단 시스템 설계 및 구현)

  • Youngjun Kim;Taewan Kim;Suhyun Kim;Seongjae Lee;Taehyoun Kim
    • IEMEK Journal of Embedded Systems and Applications
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    • v.19 no.3
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    • pp.151-158
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    • 2024
  • Although on-device artificial intelligence (AI) has gained attention to diagnosing machine faults in real time, most previous studies did not consider the model retraining and redeployment processes that must be performed in real-world industrial environments. Our study addresses this challenge by proposing an on-device AI-based real-time machine fault diagnosis system that utilizes continual learning. Our proposed system includes a lightweight convolutional neural network (CNN) model, a continual learning algorithm, and a real-time monitoring service. First, we developed a lightweight 1D CNN model to reduce the cost of model deployment and enable real-time inference on the target edge device with limited computing resources. We then compared the performance of five continual learning algorithms with three public bearing fault datasets and selected the most effective algorithm for our system. Finally, we implemented a real-time monitoring service using an open-source data visualization framework. In the performance comparison results between continual learning algorithms, we found that the replay-based algorithms outperformed the regularization-based algorithms, and the experience replay (ER) algorithm had the best diagnostic accuracy. We further tuned the number and length of data samples used for a memory buffer of the ER algorithm to maximize its performance. We confirmed that the performance of the ER algorithm becomes higher when a longer data length is used. Consequently, the proposed system showed an accuracy of 98.7%, while only 16.5% of the previous data was stored in memory buffer. Our lightweight CNN model was also able to diagnose a fault type of one data sample within 3.76 ms on the Raspberry Pi 4B device.

PROPERTIES OF HYPERHOLOMORPHIC FUNCTIONS ON DUAL TERNARY NUMBERS

  • Jung, Hyun Sook;Shon, Kwang Ho
    • The Pure and Applied Mathematics
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    • v.20 no.2
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    • pp.129-136
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    • 2013
  • We research properties of ternary numbers with values in ${\Lambda}(2)$. Also, we represent dual ternary numbers in the sense of Clifford algebras of real six dimensional spaces. We give generation theorems in dual ternary number systems in view of Clifford analysis, and obtain Cauchy theorems with respect to dual ternary numbers.

Extreme Learning Machine Approach for Real Time Voltage Stability Monitoring in a Smart Grid System using Synchronized Phasor Measurements

  • Duraipandy, P.;Devaraj, D.
    • Journal of Electrical Engineering and Technology
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    • v.11 no.6
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    • pp.1527-1534
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    • 2016
  • Online voltage stability monitoring using real-time measurements is one of the most important tasks in a smart grid system to maintain the grid stability. Loading margin is a good indicator for assessing the voltage stability level. This paper presents an Extreme Learning Machine (ELM) approach for estimation of voltage stability level under credible contingencies using real-time measurements from Phasor Measurement Units (PMUs). PMUs enable a much higher data sampling rate and provide synchronized measurements of real-time phasors of voltages and currents. Depth First (DF) algorithm is used for optimally placing the PMUs. To make the ELM approach applicable for a large scale power system problem, Mutual information (MI)-based feature selection is proposed to achieve the dimensionality reduction. MI-based feature selection reduces the number of network input features which reduces the network training time and improves the generalization capability. Voltage magnitudes and phase angles received from PMUs are fed as inputs to the ELM model. IEEE 30-bus test system is considered for demonstrating the effectiveness of the proposed methodology for estimating the voltage stability level under various loading conditions considering single line contingencies. Simulation results validate the suitability of the technique for fast and accurate online voltage stability assessment using PMU data.