• Title/Summary/Keyword: Real-time System Call

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Implementation of real time operating system (실시간 운영 체제의 구현)

  • 박병현;이진수
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.347-351
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    • 1991
  • We propose a real time kernel chimera implemented under AT&T UNIX motorola versoin, Carnegie Mellon Univ. in U.S first developed chimera using SUN Worstation with Berkley UNIX based on VMEbus. The major differences between Canegie Mellon's and ours are downloading program and communication method between host and target. Original chimera used device driver but we used UNIX system call corresponding to shared memory when user downloads program and communicates. We modified kernel itself because the two different UNIX have different link editor.

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A Platform Conception of Road Information Telecommunication System for Call & Response Service (Call & Response 서비스를 위한 도로정보통신 플랫폼 구상)

  • Yim, Choon-Sik;Lee, Ki-Young;Song, Pil-Yong
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.5
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    • pp.1-12
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    • 2008
  • In this paper, we described about core technologies required for the seamless service implementation and the communication system structure conceiving required for call & response services in order that the real-time traffic information service is consecutively provided to the vehicle moving at high speed. The SMART highway service is the information communication environment build-up concept which the real-time C&R service is comprised of the vehicle moving with 160km/h above. It was possible in case of being the low speed car in the DSRC system structure. However, there is a limit in the high speed environment as the DSRC system like a convention. In this paper, we proposed the structure of fitting for the SMART highway environment using the hand-over technique compositing the base station and several repeaters of DSRC system.

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The Implementation of a Lift Emergency Video Call System based on WebRTC using OpenAPI

  • Woon-Yong Kim
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.10
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    • pp.155-161
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    • 2023
  • In this paper, we present a WebRTC-based emergency video call system structure that builds a service system in a constant monitoring environment to increase the usability and stability of elevator emergency call devices. The proposed system provides a smooth call environment between the emergency call system in the elevator and maintenance managers in case of an emergency, performs rapid response processing to elevator emergency calls through monitoring of the target elevator, and handles any emergency calls that may occur in the physical space of the elevator. The purpose is to build an environment that can implement low-latency, real-time video call services of voice and video by overcoming the physical constraints required for video calls. To this end, we have established a service environment based on OpenAPI, which is currently used in various fields and its performance has been proven, and provides video calls and emergency situation dissemination through rapid messaging by providing low-latency call quality. The presented system structure will be able to provide a basis for expanding various functions and constructing a reliable service environment and intelligent model for the elevator system through combination with the elevator control panel and various devices.

Overload Detection and Control for Switching Systems using Fuzzy Rules

  • Rhee, Chung-Hoon;Rhee, Byung-Ho;Cho, Sung-Ho
    • The Journal of the Acoustical Society of Korea
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    • v.17 no.4E
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    • pp.28-34
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    • 1998
  • In most switching system, the processing unit is designed to work efficiently even at relatively high loads, but when the offered traffic exceeds a particular level, the rate of completed calls can fall drastically. A single call handled by the switching system consists of a sequence of events or messages that has to be processed by the control unit. The control unit is not only incapable of handling all of the offered calls, but also its call handling capability can drop as the offered load increases. The real time available for call processing is a critical resource that requires careful management. Therefore, the overloading of this resource must be detected by a subscriber in the from of a dial tone delay or an uncompleted call which is either blocked or mishandled. The subscriber may respond by either dialing prematurely or by re-attempting a call. This action can further escalate the processors load, which is spent for uncompleted calls. Unless a proper control is used, the switching system can finally break down. In this paper, we paper, we propose a fuzzy overload detection and control method for switching systems, which can by generating fuzzy rules via fuzzy aggregation networks. Simulation results involving a switching system is given.

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A new IP-based Multi-Channel Elevator Video Surveillance System (IP 기반의 다채널 엘리베이터 영상감시 시스템)

  • Shin, Jea-Hung;Kim, Hong-Ryul
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.62 no.4
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    • pp.164-168
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    • 2013
  • Recently, in the elevator of the buildings, such as apartment and office building, the visitor monitoring cameras for surveillance, advertising LCD to provide a variety of information, emergency call devices, and safe driving information sensors are installed. A variety of multimedia data from these devices to the central control office, management office, or to guard room are transmitted in real-time. Each sub-systems in the elevator are installed with a separate lines and operated independently and use different management principals, so integrated management for each sub-systems are very difficult. In this study, we develop a new IP-based multi-channel video surveillance system which is integrated surveillance camera, emergency call devices, communications devices, various sensors in the elevator, DVR, ODM, and can manage all devices by two-way communication and integrated interface. And we evaluated the performance of the developed system.

Implementation for Real-Time of MIL-STD-1553B Communication in Inspection Equipment Based on Windows with RTiK and DPC Control (RTiK과 DPC 제어를 통한 윈도우즈 기반의 검사장비에서 MIL-STD-1553B 통신의 실시간 구현)

  • Kim, Jong-Jin;Lee, Sang-Gil;Lee, Cheol-Hoon
    • Journal of Korea Multimedia Society
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    • v.24 no.2
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    • pp.199-207
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    • 2021
  • It is very important to support real-time on the inspection equipment based on Windows. In particular, in the system using MIL-STD-1553B communication, which is widely used in military weapon systems, real-time is required for inspection equipment that uses mostly platforms based on Windows such as Industrial PCs. However, in order to use a complete real-time operating system such as VxWorks, the purchase cost is expensive and the implementation is complicated on the system, so it is not suitable for inspection equipment that requires simple functions to just check go or no-go. Therefore, in this paper, a Real-Time implanted Kernel(RTiK) in the Windows kernel is implanted in order to improve these defects, and real-time performance is implemented for periodically MIL-STD-1553B communication by Deferred Procedure Call(DPC) of Windows. Also, it was verified that the period of up to 2ms was guaranteed with a RDTSC into the EDX:EAX registers for measuring the periodicity.

A Mask Wearing Detection System Based on Deep Learning

  • Yang, Shilong;Xu, Huanhuan;Yang, Zi-Yuan;Wang, Changkun
    • Journal of Multimedia Information System
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    • v.8 no.3
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    • pp.159-166
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    • 2021
  • COVID-19 has dramatically changed people's daily life. Wearing masks is considered as a simple but effective way to defend the spread of the epidemic. Hence, a real-time and accurate mask wearing detection system is important. In this paper, a deep learning-based mask wearing detection system is developed to help people defend against the terrible epidemic. The system consists of three important functions, which are image detection, video detection and real-time detection. To keep a high detection rate, a deep learning-based method is adopted to detect masks. Unfortunately, according to the suddenness of the epidemic, the mask wearing dataset is scarce, so a mask wearing dataset is collected in this paper. Besides, to reduce the computational cost and runtime, a simple online and real-time tracking method is adopted to achieve video detection and monitoring. Furthermore, a function is implemented to call the camera to real-time achieve mask wearing detection. The sufficient results have shown that the developed system can perform well in the mask wearing detection task. The precision, recall, mAP and F1 can achieve 86.6%, 96.7%, 96.2% and 91.4%, respectively.

A Study of Systematic Implementations for the Integrated ITS call center (교통정보 안내전화 통합연계시스템 구축에 관한 연구)

  • Chung, Sung-Hak
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.1
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    • pp.205-216
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    • 2009
  • The aim of this study is to propose an integrated operation plan of information call services by multi-connecting call services which are now being serviced by each different call number services and by providing one stop service which organically links alternative transportations such as railroad, air, and bus and also related organizations as well as road traffic information. For the objective, we analyzed the current status of Korean and foreign country systems and reviewed operation technology and technical specifications of the integrated system according to 3 steps, i.e. infrastructure procurement, test bed and extended completion, stabilization and high valuable services completion. Throughout the result of this study, traffic information one stop service, convenient service, diverse related information provision service, real-time information provision, and efficient system are expected to be implemented in the traffic information call service.

Development of e-CRM System Using LBS of Cellular Phone and Call Back URL SMS (휴대폰의 위치기반서비스와 Call Back URL SMS를 이용한 e-CRM 시스템 개발)

  • Jeon, Jin-Ho;Seo, Phil-Kyo
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.3
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    • pp.121-128
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    • 2010
  • Whenever and wherever, recognizing location of object such as human as well as things, ubiquitous Location-Based Service which provides useful service based on this are rising as an important service. In this paper, we implemented customized real time 1:1 e-CRM system that can communicate with user's mobile phone through using Location-Based Service of mobile phone. Among various scenarios that are applicable to designed system, development and test were conducted based on scenario that provides shopping information and discount information to customers through SMS as they approach to vicinity of large discount store and allow them to download discount coupons through Call Back. The suggested system will be applied to various service event and can be used as a customized real time marketing method according to user's personal activity area.

An Integrated Emergency Call System based on Public Switched Telephone Network for Elevators

  • Lee, Guisun;Ryu, Hyunmi;Park, Sunggon;Cho, Sungguk;Jeon, Byungkook
    • International journal of advanced smart convergence
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    • v.8 no.3
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    • pp.69-77
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    • 2019
  • Today, most of elevators have an emergency call facility for emergency situations. However, if the network installed in the elevator is also out of power, it cannot be used for the elevator remote monitoring and management. So, we develop an integrated and unified emergency call system, which can transmit not only telephone call but also data signals using PSTN(Public Switched Telephone Network) in order to remote monitoring and management of elevators, even though a power outage occurs. The proposed integrated emergency call system to process multiple data such as voice and operational information is a multi-channel board system which is composed of an emergency phone signal processing module and an operational information processing module in the control box of elevator. In addition, the RMS(remote management server) systems based on the Web consist of a dial-up server and a remote monitoring server where manages the elevator's operating information, status records, and operational faults received via the proposed integrated and unified emergency call system in real time. So even if there's a catastrophic emergency, the proposed RMS systems shall ensure and maintain the safety of passengers inside the elevator. Also, remote control of the elevator by this system should be more efficient and secure. In near future, all elevator emergency call system need to support multifunctional capabilities to transmit operational data as well as phone calls for the safety of passengers. In addition, for safer elevators, it is necessary to improve them more efficiently by combining them with high-tech technologies such as the Internet of Things and artificial intelligence.