• Title/Summary/Keyword: Operating systems

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The Factors Towards the User Satisfaction of Interorganizational System (기업간 정보시스템의 사용자 만족도에 영향을 주는 요인)

  • Son, Dal-Ho
    • Asia pacific journal of information systems
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    • v.11 no.1
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    • pp.75-90
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    • 2001
  • Computer-based systems operating between two or more co-operating organizations as part of their business relationship are generally referred to as inter-organizational systems(IOS). IOS automates aspects of transactional work between organizations and coordinate other activities. These systems facilitate organizational interaction as well as flows of materials, services and information. This planning provides as business direction for IOS applications, coordinates the efforts of participants, and deals with technical and non-technical IOS issues. This paper seeks to research the effect of strategic determinants of IOS to the efficiency of IOS. The determinants that selected from prior researches are top management support, is support and vendor/consultant support. The results show that the effect of top management support to efficiency of IOS was significant and this effect mediates the effect of other factors.

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Complex Discrete Systems Graph Simulation

  • Kadirova, Delovar;Kadirova, Aziza
    • Journal of Multimedia Information System
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    • v.2 no.3
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    • pp.263-274
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    • 2015
  • The subject of this work is the complex discrete systems simulation special features with the aid of dynamic graph models. The proposed simulation technique allows to determine the ways for tasks solutions in terms of discrete systems analysis and synthesis of various complication: one-dimensional and multidimensional, steady and unstable, with the pulse elements abnormal operating mode and others. Often complex control systems analysis and synthesis task solutions, via classical approach comes out to be insolvent, because of the computational problems. The application of graph models allows to perform clear and strict characterization and computer procedures automation. The optimal controls synthesis algorithm presented in this paper, transferring the discrete system from target initial state to target final state within the minimum time, allows to consider the zero initial conditions systems, with the initial potential energy, with the control actions limitations and complex pulse elements operating mode.

An Implementation of Single Stack Multi-threading for Small Embedded Systems

  • Kim, Yong-Seok
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.4
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    • pp.1-8
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    • 2016
  • In small embedded systems including IoT devices, memory size is very small and it is important to reduce memory amount for execution of application programs. For multi-threaded applications, stack may consume a large amount of memory because each thread has its own stack of sufficiently large size for worst case. This paper presents an implementation of single stack multi-threading, called SSThread (Single Stack Thread), by sharing a stack for all threads to reduce stack memory size. By using SSThread, multi-threaded applications can be programmed based on normal C language environment and there is no requirement of transporting multi-threading operating systems. It consists of several library functions and various C macro definitions. Even though some functional restrictions in comparison to operating systems supporting complete multi-thread functionalities, it is very useful for small embedded systems with tiny memory size and it is simple to setup programming environment for multi-thread applications.

Development of Operation Network System and Processor in the Loop Simulation for Swarm Flight of Small UAVs (소형 무인기들의 군집비행을 위한 운영 네트워크 시스템과 PILS 개발)

  • Kim, Sung-Hwan;Cho, Sang-Ook;Cho, Seong-Beom;Park, Choon-Bae
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.5
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    • pp.433-438
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    • 2012
  • In this paper, a operation network system equipped with onboard wireless communication systems and ground-based mission control systems is proposed for swarm flight of small UAVs. This operating system can be divided into two networks, UAV communication network and ground control system. The UAV communication network is intend to exchange the informations of navigation, mission and flight status with minimum time delay. The ground control system consisted of mission control systems and UDP network. Proposed operation network system can make a swarm flight of various UAVs, execute complex missions decentralizing mission to several UAVs and cooperte several missions. Finally, PILS environments are developed based on the total operating system.

Design of an embeded intelligent controller

  • Shirakawa, Hiromitsu;Hayashi, Tsunetoshi;Ohno, Yutaka
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1399-1404
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    • 1990
  • There is an increasing need to apply artificial intelligence to the real application fields of industry. These include an intelligent process control, an expert machine and a diagnostic and/or maintenance machine. These applications are implemented in AI Languages. It is commonly recognized that AI Languages, such as Common Lisp or Prolog, require a workstation. This is mainly due to the fact that both languages need a large amount of memory space and disk storage space. Workstations are appropriate for a laboratory or office environment. However, they are too bulky to use in the real application fields of industry or business. Also users who apply artificial intelligence to these fields wish to have their own operating systems. We propose a new design method of an intelligent controller which is embedded within equipment and provides easy-to-use tools for artificial intelligence applications. In this paper we describe the new design method of a VMEbus based intelligent controller for artificial intelligence applications and a small operating system which supports Common Lisp and Prolog.

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A Study of Traction Power System Reliability (철도 급전시스템 신뢰도 평가 연구)

  • Kim Hyungchul;Cha Jun-Min;Kim Jin-O;Han Moonseob
    • Proceedings of the KSR Conference
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    • 2005.05a
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    • pp.806-812
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    • 2005
  • This paper proposes a new reliability evaluation for traction power system. The electric railway consists of traction power systems, various vehicles, operating equipment, track, overhead line and electric equipment. It is a fundamental function of traction power systems that supply customers with reasonable price, acceptable reliability and high quality power. In a general way, the power system reliability deals with the ability to satisfy load demands in supply capability or rating of every factor. On the other hand, the reliability of traction power systems has been focused on train time delay caused by power outage. In this paper, we make a selection optimum reliability indices for the reliability evaluation of electric traction power systems. The reliability study not only applies a plan for traction supply system after detecting the vulnerable point of existing traction supply systems but also makes a role in stable operating railway.

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Development of Operation System for Network of Multiple UAVs (복수 무인기 네트워크 통합 운영 시스템 개발)

  • Kim, Sung-Hwan;Cho, Sang-Ook;Kim, Sung-Su;Ryoo, Chang-Kyung;Choi, Kee-Young
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.39 no.11
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    • pp.1042-1051
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    • 2011
  • In this paper, a total operating environment equipped with onboard wireless communication systems and ground-based mission control systems is proposed for simultaneous operation of multiple UAVs. A variety of operating structures are studied and classified systematically based on types and usages of the components. For each operating system, the strength, weakness and reliability aspects are investigated. Based on these results, a proper operating system configuration is determined and components are developed for mission formation flight. Proposed system can make a formation flight of various UAVs, execute complex missions decentralizing mission to several UAVs and cooperate several missions.

Computations of the Supersonic Ejector Flows with the Second Throat (2차목을 가지는 초음속 이젝터 유동에 관한 수치계산)

  • Choi, Bo-Gyu;Lee, Young-Ki;Kim, Heuy-Dong;Kim, Duck-Jool
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.8
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    • pp.1128-1138
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    • 2000
  • Pumping action in ejector systems is generally achieved through the mixing of a high-velocity and high-energy stream with a lower-velocity and lower-energy stream within a duct. The design and performance evaluation of the ejector systems has developed as a combination of scale-model experiments, empiricism and theoretical analyses applicable only to very simplified configurations, because of the generic complexity of the flow phenomena. In order to predict the detailed performance characteristics of such systems, the flow phenomena throughout the operating regimes of the ejector system should be fully understood. This paper presents the computational results for the two-dimensional supersonic ejector system with a second throat. The numerical simulations are based on a fully implicit finite volume scheme of the compressible Reynolds-averaged Navier-Stokes equation in a domain that extends from the stagnation chamber to the diffuser exit. For a wide range of the operating pressure ratio the flow field inside the ejector system is investigated in detail. The results show that the supersonic ejector systems have an optimal throat area for the operating pressure ratio to be minimized.

A High Performance Interleaved Bridgeless PFC for Nano-grid Systems

  • Cao, Guoen;Lim, Jea-Woo;Kim, Hee-Jun;Wang, Huan;Wang, Yibo
    • Journal of Electrical Engineering and Technology
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    • v.12 no.3
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    • pp.1156-1165
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    • 2017
  • A high performance interleaved bridgeless boost power factor correction (PFC) rectifier operating under the critical current conduction mode (CrM) is proposed in this paper to improve the efficiency and system performance of various applications, such as nano-grid systems. By combining the interleaved technique with the bridgeless topology, the circuit contains two independent branches without rectifier diodes. The branches operate in interleaved mode for each respective half-line period. Moreover, when operating in CrM, all the power switches take on soft-switching, thereby reducing switching losses and raising system efficiency. In addition, the input current flows through a minimum amount of power devices. By employing a commercial PFC controller, an effective control scheme is used for the proposed circuit. The operating principle of the proposed circuit is presented, and the design considerations are also demonstrated. Simulations and experiments have been carried out to evaluate theoretical analysis and feasibility of the proposed circuit.

Aeroengine performance degradation prediction method considering operating conditions

  • Bangcheng Zhang;Shuo Gao;Zhong Zheng;Guanyu Hu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.9
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    • pp.2314-2333
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    • 2023
  • It is significant to predict the performance degradation of complex electromechanical systems. Among the existing performance degradation prediction models, belief rule base (BRB) is a model that deal with quantitative data and qualitative information with uncertainty. However, when analyzing dynamic systems where observable indicators change frequently over time and working conditions, the traditional belief rule base (BRB) can not adapt to frequent changes in working conditions, such as the prediction of aeroengine performance degradation considering working condition. For the sake of settling this problem, this paper puts forward a new hidden belief rule base (HBRB) prediction method, in which the performance of aeroengines is regarded as hidden behavior, and operating conditions are used as observable indicators of the HBRB model to describe the hidden behavior to solve the problem of performance degradation prediction under different times and operating conditions. The performance degradation prediction case study of turbofan aeroengine simulation experiments proves the advantages of HBRB model, and the results testify the effectiveness and practicability of this method. Furthermore, it is compared with other advanced forecasting methods. The results testify this model can generate better predictions in aspects of accuracy and interpretability.