• 제목/요약/키워드: Real-time issues

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소형 무인 항공기를 위한 다중 실시간 미션 소프트웨어 통합 시스템 (Integrated System of Multiple Real-Time Mission Software for Small Unmanned Aerial Vehicles)

  • 조현철;박근영;전동운;진현욱;김두현
    • Telecommunications review
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    • 제24권4호
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    • pp.468-480
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    • 2014
  • 오늘날 개발되는 항공전자 시스템에서는 연합 구조(Federated Architecture)를 기반으로 전자장치들이 각각 하나의 소프트웨어 모듈이나 응용 프로그램을 수행하고 있으며 이들은 네트워크를 통해 연결된다. 이러한 연합 구조는 전체 시스템을 매우 복잡하게 하며 SWaP(Size, Weight and Power) 문제를 일으킬 수 있다. 본 논문은 이러한 문제가 특히 심각한 소형 무인 항공기에서 ARINC 653이 정의하고 있는 파티셔닝 기술을 활용하여 여러 임무 소프트웨어를 통합 운영하고 SWaP 문제를 효과적으로 해결할 수 있음을 보인다. 본 논문은 특히 실제 헥사콥터와 쿼드콥터에 통합 임무 시스템을 탑재하여 시험 비행을 성공적으로 수행했음을 보인다. 본 연구를 통해서 제시되는 통합 임무 소프트웨어를 운영하기 위해서 필요한 소프트웨어 기술과 통합 방법론은 SWaP이 중요한 다양한 실시간 시스템에 응용될 수 있다.

실시간 우편물류 운영시스템 설계에 관한 연구 (Design for Real-Time Postal Logistics Operational System)

  • 이기백;김완석;박종흥
    • 산업공학
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    • 제20권4호
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    • pp.547-559
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    • 2007
  • In this paper, we design Real-Time Postal Logistics Operational Model and System as a to-be system. Current postal logistics information system, named PostNet, is a basic infra system designed for an end-to-end IT-driven process, from mail acceptance to delivery, linked with internal and external systems. Recent competing circumstances drive demand for more intelligent information system. So we design real-time postal logistics operational system focused on site operations. we analyze postal logistics operation and interview field workers and establish real-time postal logistics operational model to solve operational issues. Finally we suggest system specifications.

실시간 기반 우편 물류 정보시스템 모형 설계 (A Design for the Real-Time Enterprise based Logistics Information System of Postal Service)

  • 선지웅;송영효
    • 산업공학
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    • 제20권2호
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    • pp.162-176
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    • 2007
  • As facing the rapid advance of information technologies, the postal service is required to have capabilities of real-time logistics characterized by collaboration, ubiquity and intelligence which are necessary to the organizational management. In this study we discuss the design of the next generation information system based on real-time enterprise strategy to achieve real-time integrity and upgrade of postal information system. After briefly addressing the issues on developing information system and current situation, we provide the design direction and the framework of the to-be system. We develop detailed specification of each subsystem and provide an operational scenario. We believe when this framework is put into use, it can contribute to competitive performance by giving the integrity and consistency in implementing information systems of the Korea Postal Service.

Augmented Reality Annotation for Real-Time Collaboration System

  • Cao, Dongxing;Kim, Sangwook
    • 한국멀티미디어학회논문지
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    • 제23권3호
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    • pp.483-489
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    • 2020
  • Advancements in mobile phone hardware and network connectivity made communication becoming more and more convenient. Compared to pictures or texts, people prefer to share videos to convey information. For intentions clearer, the way to annotating comments directly on the video are quite important issues. Recently there have been many attempts to make annotations on video. These previous works have many limitations that do not support user-defined handwritten annotations or annotating on local video. In this sense, we propose an augmented reality based real-time video annotation system which allowed users to make any annotations directly on the video freely. The contribution of this work is the development of a real-time video annotation system based on recent augmented reality platforms that not only enables annotating drawing geometry shape on video in real-time but also drastically reduces the production costs. For practical use, we proposed a real-time collaboration system based on the proposed annotation method. Experimental results show that the proposed annotation method meets the requirements of real-time, accuracy and robustness of the collaboration system.

의사결정 트리를 이용한 학습 에이전트 단기주가예측 시스템 개발 (A Development for Short-term Stock Forecasting on Learning Agent System using Decision Tree Algorithm)

  • 서장훈;장현수
    • 대한안전경영과학회지
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    • 제6권2호
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    • pp.211-229
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    • 2004
  • The basis of cyber trading has been sufficiently developed with innovative advancement of Internet Technology and the tendency of stock market investment has changed from long-term investment, which estimates the value of enterprises, to short-term investment, which focuses on getting short-term stock trading margin. Hence, this research shows a Short-term Stock Price Forecasting System on Learning Agent System using DTA(Decision Tree Algorithm) ; it collects real-time information of interest and favorite issues using Agent Technology through the Internet, and forms a decision tree, and creates a Rule-Base Database. Through this procedure the Short-term Stock Price Forecasting System provides customers with the prediction of the fluctuation of stock prices for each issue in near future and a point of sales and purchases. A Human being has the limitation of analytic ability and so through taking a look into and analyzing the fluctuation of stock prices, the Agent enables man to trace out the external factors of fluctuation of stock market on real-time. Therefore, we can check out the ups and downs of several issues at the same time and figure out the relationship and interrelation among many issues using the Agent. The SPFA (Stock Price Forecasting System) has such basic four phases as Data Collection, Data Processing, Learning, and Forecasting and Feedback.

A Timing Constraint Search Technique for a TMO based Real-time Process

  • Jeong, Yoon-Seok;Kim, Tae-Wan;Han, Sun-Young;Chang, Chun-Hyon
    • Journal of Information Processing Systems
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    • 제2권1호
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    • pp.1-5
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    • 2006
  • Finding a valid timing constraint is one of the most important issues in the real-time monitoring area. To get the valid timing constraint, a developer executes a real-time process and changes the constraint on a regular basis. This is an exhaustive and time-consuming process. To improve this approach, we propose a timing constraint search technique. This technique uses two load models and one condition proposed in this paper to support the developer in determining the valid timing constraint range in an easy and systematic manner.

결함허용 실시간 시스템 구조에 대한 설계 및 구현 (Design and Implementation of a Architecture For Fault-Tolerant and Real-Time System)

  • 유종상;김범식;신인철
    • 한국산업정보학회:학술대회논문집
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    • 한국산업정보학회 1997년도 추계학술대회 발표논문집:21세기를 향한 정보통신 기술의 전망
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    • pp.417-433
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    • 1997
  • A real-time operating system has focused primary on techniques to minimize processing time, with a secondary emphasis on system reliability issues. Conversely, fault-tolerant system has concentrated on using recourse and information redundancy to maximize the availability and reliability of the system, with a lesser emphasis on performance. We have developed a fault-tolerant and real-time operations system which support a powerful concurrent runtime environment under the above requirements. In this paper, we present an overview of real-time systems, design and implementation of a duplex architecture using advanced concepts and technologies such as fast " fault detection", "fault isolation" and "fault recovery" Because the duplex architecture has two dentical hardware elements and has several recovery steps and hierarchy to facilitate a fast recovery which must be proceeded by a prompt fault detection and isolation. Thus it makes possible to minimize the overhead of the systems including hardware and software and guarantee the service continuity of he systems.

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DETAILS OF PRACTICAL IMPLEMENTATION OF REAL-TIME 3D TERRAIN MODELING

  • Young Suk Kim;Seungwoo Han;Hyun-Seok Yoo;Heung-Soon Lim;Jeong-Hoon Lee;Kyung-Seok Lee
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.487-492
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    • 2009
  • A large-scaled research project titled "Intelligent Excavating System (IES)" sponsored by Korean government has launched in 2006. An issue of real-time 3D terrain modeling has become a crucial point for successful implementation of IES due to many application limitations of state-of-the-art techniques developed in various high-technology fields. Many feasible technologies such as laser scanning, structured lighting and so on were widely reviewed by professionals and researchers for one year. Various efforts such as literature reviews, interviews, and indoor experiments make us select a structural light technique and stereo vision technique as appropriate techniques for accomplishment of real-time 3D terrain modeling. It, however, revealed that off-the-shelf products of structural light and stereo-vision technique had many technical problems which should be resolved for practical applications in IES. This study introduces diverse methods modifying off-the-shelf package of the structural light method, one of feasible techniques and eventually allowing this technique to be successfully utilized for achieving fundamental research goals. This study also presents many efforts to resolve practical difficulties of this technique considering basic characteristics of excavating operations and particular environment of construction sites. Findings showed in this study would be beneficial for other researchers to conduct new researches for application of vision techniques to construction fields by provision of detail issues about practical application and diverse practical methods as solutions overcoming these issues.

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Hierarchical Real-Time MAC Protocol for (m,k)-firm Stream in Wireless Sensor Networks

  • Teng, Zhang;Kim, Ki-Il
    • Journal of information and communication convergence engineering
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    • 제8권2호
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    • pp.212-218
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    • 2010
  • In wireless sensor networks (WSNs), both efficient energy management and Quality of Service (QoS) are important issues for some applications. For creating robust networks, real-time services are usually employed to satisfy the QoS requirements. In this paper, we proposed a hierarchical real-time MAC (medium access control) protocol for (m,k)-firm constraint in wireless sensor networks shortly called HRTS-MAC. The proposed HRTS-MAC protocol is based on a dynamic priority assignment by (m,k)-firm constraint. In a tree structure topology, the scheduling algorithm assigns uniform transmitting opportunities to each node. The paper also provides experimental results and comparison of the proposed protocol with E_DBP scheduling algorithm.

A Real-Time MAC Protocol with Extended Backoff Scheme for Wireless Sensor Networks

  • Teng, Zhang;Kim, Ki-Il
    • Journal of information and communication convergence engineering
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    • 제9권3호
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    • pp.341-346
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    • 2011
  • Wireless sensor networks (WSNs) are formed by a great quantity of sensor nodes, which are consisted of battery-powered and some tiny devices. In WSN, both efficient energy management and Quality of Service (QoS) are important issues for some applications. Real-time services are usually employed to satisfy QoS requirements in critical environment. This paper proposes a real-time MAC (Medium Access Control) protocol with extended backoff scheme for wireless sensor networks. The basic idea of the proposed protocol employs (m,k)-firm constraint scheduling which is to adjust the contention window (CW) around the optimal value for decreasing the dynamic failure and reducing collisions DBP (Distant Based Priority). In the proposed protocol, the scheduling algorithm dynamically assigns uniform transmitting opportunities to each node. Numerical results reveal the effect of the proposed backoff mechanism.