• Title/Summary/Keyword: Embedded linux system

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I/O Performance Analysis about Memory Allocation of the UBIFS (UBIFS 메모리 할당에 관한 I/O 성능 분석)

  • Lee, Jaekang;Oh, Sejin;Chung, Kyungho;Yun, Taejin;Ahn, Kwangseon
    • Journal of Korea Society of Industrial Information Systems
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    • v.18 no.4
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    • pp.9-18
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    • 2013
  • Flash memory is mostly used on smart devices and embedded systems because of its nonvolatile memory, low power, quick I/O, resistant shock, and other benefits. Generally the typical file systems base on the NAND flash memory are YAFFS2, JFFS2, UBIFS, and etc. In this paper, we had variously made an experiment regarding I/O performance using our schemes and the UBIFS of the latest Linux Kernel. The proposed I/O performance analyses were classified as a sequential access and a random access. Our experiment consists of 6 cases using kmalloc(), vmalloc(), and kmem_cache(). As a result of our experiment analyses, the sequential reading and the sequential rewriting increased by 12%, 11% when the Case 2 has applied vmalloc() and kmalloc() to the UBI subsystem and the UBIFS. Also, the performance improved more by 7.82%, 6.90% than the Case 1 at the random read and the random write.

Design and Implementation of LED Lighting Control System Using Arduino Yun and Cloud in IoT (사물인터넷에 아두이노 윤과 클라우드를 이용한 LED 조명 제어 시스템 설계)

  • Xu, Hao;Kim, Chul-Won
    • The Journal of the Korea institute of electronic communication sciences
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    • v.11 no.10
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    • pp.983-988
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    • 2016
  • Internet of Things Iranian people and things, things and things are connected through the Cloud. It can significantly save energy through a combination of LED lighting as a new ICT technologies and industry-to provide a human-centric, eco-friendly, and the content is embedded multifunction solutions that meet your needs, environment, implementation time according to user requirements, technology It can be systematized as converged next-generation lighting. In this paper, we have developed regarding whether the building in relation to the LED lighting control system using smart devices and Cloud-based user as a human connection through the board to the Arduino Yun lit LED lighting, wireless smart device or to the Cloud or off. After the Arduino Yun is connected to the Internet, taking the current date and time information from the Linux shell command used the way coming across the bridge (BRIDGE) its value.

A Robotcar-based Proof of Concept Model System for Dilemma Zone Decision Support Service (딜레마구간 의사결정 지원 서비스를 위한 로봇카 기반의 개념검증 모형 시스템)

  • Lee, Hyukjoon;Chung, Young-Uk;Lee, Hyungkeun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.13 no.4
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    • pp.57-62
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    • 2014
  • Recently, research activities to develop services for providing safety information to the drivers in fast moving vehicles based on various wireless network technologies such as DSRC (Dedicated Short Range Communication), IEEE 802.11p WAVE (Wireless Access for Vehicular Environment) are widely being carried out. This paper presents a proof-of-concept model based on a robot-car for Dilemma Zone Decision Assistant Service using the wireless LAN technology. The proposed model system consists of a robot-car based on an embedded Linux OS equipped with a WiFi interface and an on-board unit emulator, an Android-based remote controller to model a human driver interface, a laptop computer to run a model traffic signal controller and signal lights, and a WiFi access point to model a road-side unit.

Design and Implementation of $\pi/4$ QPSK Satellite IP Modem Part ($\pi/4$ QPSK 위성 IP 모뎀부 설계 및 구현)

  • Kang, Jung-Mo;Jung, Jae-Wook;Kim, Myung-Sik;Oh, Woo-Jin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.10
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    • pp.1858-1865
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    • 2007
  • In this paper, we introduce the design and implementation of satellite IP modem. The designed satellite IP modem shows the performance of 0.2% overhead, BER=10-5 when Eb/No=6dB, frequency offset of 8KHz, data rate up to 1536Kbps, $F_{if}=140MHz$. The designed system is verified through software simulation and then implemented with MPC86x communication processor, TMS320C6416 DSP, and Altera FPGA. Since each hardware unit is implemented in daughter board for modularity, we can reduce the development time and easily improve the performance with using better processor. Linux is used for embedded OS because it shows better performance in IP manipulation multitask processing, and hardware control through device driver. The implemented system is tested and verified with channel simulator. Since the proposed IP modem shows small size and light weight, that can be used anywhere with easy if you need IP environment.

Design and Implementation of UHF RFID Reader System Supporting Sensor Data Processing (센서 데이터 처리를 지원하는 UHF RFID 리더 시스템의 설계 및 구현)

  • Shin, Dong-Beom;Lee, Heyung-Sub;Choi, Gil-Young;Kim, Dae-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12A
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    • pp.925-932
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    • 2009
  • Precise temperature monitoring is the major preconditioning to supervise quality losses within the transport chain for fresh products. ISO/IEC18000-6REV1 defines new protocols supporting BAP(Battery Assisted Passive) RFID tag which is completely compatible with EPCglobal Class1 Generation2 specification. In this paper, we designed a modem supporting BAP RFID tag with FPGA(Field Programmable Gate Array) and implemented sensor data processing function defined in ISO/IEC18000-6REV1. The transmit block of the modem supports pulse shaping filter and the output signal of the implemented RFID reader is satisfied with the spectrum mask defined in the standard. The receive block of the modem uses Gardner TED to synchronize timing of symbol. In this paper, we designed a modem supporting ISO/IEC18000-6REV1 standard and developed a RFID reader sndard. The developed RFID reader sndard can recognize sensor tag and passive tag in the wireless environment and supports real-time processing of the sensor data in the embedded linux platform.

IP-PBX System of RasPBX-Based (RasPBX 기반의 IP-PBX 시스템)

  • Jeong, Dae-Jin;Song, Hyun-Ok;Jung, Hoe-kyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.5
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    • pp.1131-1136
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    • 2015
  • VoIP and IP Telephony telephony technology development is a growing by easy to using IP-PBX by using phone from using existing lines rather than the internet. IP-PBX do not use the phone line from phone work for many companies and institutions of management costs reduce as provides similar to regular phone line quality. But IP-PBX to introduce for need to be the initial cost on is should buy for expensive hardware equipment or commercial software. In this paper, suggest way to introduce IP-PBX do not buy expensive hardware equipment or commercial software. Suggest IP-PBX on designed and implement for IP-PBX server using Raspberry Pi and Asterisk. And verification treatise on the suitability of conducted by voice calls based on IP-PBX between PC and a Smartphone