• Journal of Digital Contents Society
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• v.14 no.2
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• pp.215-222
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• 2013

NAND flash memory-based Solid State Drives (SSD) have lots of merits compared to traditional hard disk drives (HDD). However, random write in SSD is still far slower than sequential read/write and random read. There are two independent approaches to resolve this problem: 1) using part of the flash memory blocks as log blocks, and 2) using internal write buffer (DRAM or Non-Volatile RAM) in SSD. While log blocks are managed by the Flash Translation Layer (FTL), write buffer management has been treated separately from FTL. Write buffer management schemes did not use the exact status of log blocks and log block management schemes in FTL did not consider the behavior of write buffer management scheme. In this paper, we first show that log blocks and write buffer have a tight relationship to each other, which necessitates integrated management of both of them. Since log blocks also can be viewed as another type of write buffer, we can manage both of them as an integrated write buffer. Then we provide three design criteria for the integrated write buffer management scheme which can be very useful to SSD firmware designers.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.10
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• pp.38-48
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• 2007

The increasing demand on the use of multimedia video contents drives more mobile embedded systems to incorporate H.264/AVC decoding capability. An H.264/AVC decoder often requires high computation bandwidth during its decoding phase. Depending upon processor computation capability and multimedia contents complexity, the decoder can be implemented either in hardware or software. However, without a thorough analysis on the Performance and resource requirements, it is difficult to choose a cost-effective methodology of implementing this codec. This paper presents both hardware and software implementation of H.264/AVC decoding subsystem in mobile embedded systems, and quantitatively analyses the performance and resource requirements. It also shows the methodology to identify performance bottleneck in Linux-based mobile embedded systems, which is in turn used to select feasible and efficient implementation methodology.

• Journal of IKEEE
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• v.15 no.4
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• pp.267-273
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• 2011

In hardware design, its stability and reliability are important, because a hardware error can cause serious damages or disaster. To improve stability and reliability, this paper presents the implementation of the hardware verification system using the fault injection method in PC environment. This paper presents a verification platform that can verify hardware system reliably and effectively, through a process to generate faults as well as insert input signals into the actual running system environment. The verification system is configured to connect a PC with a digital I/O card, and it can transmit or receive signals from the target system, as a verifier's intention. In addition, it can generate faults and inject them into the target system. And it can be monitored by displaying the received signals from the target system to the graphical wave signals. We can evaluate its reliability by analyzing the graphical wave signals. In this paper, the proposed verification system has been applied to the FPGA firmware of a nuclear power plant control system. As a result, we found its usefulness and reliability.

• Information and Communications Magazine
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• v.25 no.4
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• pp.5-10
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• 2008

지능형 로봇은 자율적으로 이동할 수 있어야 한다는 것이 PC와 기본적으로 다른 점이다. 이동 로봇이 자율 주행할 때 꼭 필요한 기술이 위치 인식 기술과 장애물 감지 기술이다. 장애물 감지 기술은 이동 로봇이 다른 물체와 충돌하지 않도록 하기 위해 필요한 기술이지만 위치 인식 기술은 로봇이 현재 위치를 알고 목적지로 주행하기 위해 매우 중요한 기술이다. 지능형 로봇의 자율 주행 측면에서 위치 인식 기술은 필수적 핵심 기술이다. 위치 인식 센서는 로봇의 절대 위치 및 방향각 정보를 획득하여 실시간으로 관련 데이터를 지능형 로봇에 전달한다. 이로써 지능형 로봇의 이동 경로와 방향 제어가 가능해지고, 로봇을 보다 안정적으로 제어할 수 있다. 즉 로봇이 자기 위치를 인식한 후에야 안정적이고 지속적인 자율 주행이 가능해진다. (주)나인티시스템은 네트워크 기반 위치 파악용 indoor GPS 개념으로 로봇 위치 파악 센서 iGS를 개발하여 공급하고 있다. (주)나인티시스템이 개발한 iGS는 지능형 로봇의 거리, 위치, 방향을 파악하기 위해 초음파 송/수신부 및 RF 모듈로 Handware가 구성되어 있고 위치 추정 알고리즘, 장애물에 강건한 알고리즘 등이 Firmware를 구성하고 있다. 로봇 시장의 잠재적 성장 가능성을 고려할 때 로봇의 자율 운용에 필수적인 위치 파악 요소 기술을 선개발하여 상업화하는 것은 경제적으로도 큰 의미를 갖는다. 뿐만 아니라 위치 파악 요소 기술의 선도적 개발에 의해 미래 지능형 로봇시장을 주도할 수 있는 계기도 기대할 수 있다. Robot에 적정 가격대의 위치 인식 기술이 접목되면 Robot 산업의 활성화가 가능하다. 현재 청소용 Robot은 충돌 방지정도의 인식을 하고 있지만 위치 인식 기술이 접목되면 청소용 Robot이 더 많은 Service를 제공할 수 있다. 더 많은 Service의 실행으로 Robot 산업이 활성화되면 관련 요소기술 산업이 활성화된다. Robot 산업과 부품 산업이 활성화되면 Robot 관련 산업의 수익 Model이 다양해 진다. 위치 인식 기술은 Robot 산업뿐 아니라 산업 전반의 활성화에도 크게 기여할 것이다. 위치 인식 기술은 지능형 Robot의 자율 주행뿐 아니라 다양한 분야에 응용이 가능하다. 또한 위치 인식 기술을 국산화하면 기존 수입품을 대체할 뿐아니라 수출 시장의 진출에도 크게 기여할 수 있다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.9
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• pp.2087-2092
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• 2015

Recently, use of the heat transferring machine and systems has been increasing in various industrial fields. A key technique for constructing such process is basically to measuring temperature directly to objects established on industrial plants. Particularly, a non-contact temperature measurement is very important to realize advanced heat transferring systems. This paper presents a new measurement methodology for temperature by using USN(ubiquitous sensor networks) technique including the microprocessor unit based ZigBee communication systems. This proposed system is made to be applied in monitoring systems for non-contact temperature measurement. We designed firmware based measurement systems whose main function is to save s series of temperature data sets and send it to main monitoring systems.

• Journal of Drive and Control
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• v.13 no.1
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• pp.1-9
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• 2016

Nowadays automatic transmission equipped vehicles prevail in construction and agricultural equipment due to their convenience in driving and operation. Though domestic vehicle manufacturers install imported electronic controlled transmissions at present, overseas products will be replaced by domestic ones in the near future owing to development efforts over the past 10 years. For passenger cars, there are many kinds of shift control algorithms that enhance the shift quality such as feedback and learning control. However, since shift control technologies for heavy duty vehicles are not highly developed, it is possible to improve the shift quality with an organized control method. A feedback control algorithm for neutral-into-gear shift, which is enabled during the inertia phase for the master clutch slip speed to track the slip speed reference, is proposed based on the power transmission structure of TH100. The performance of the feedback shift control is verified by a vehicle test which is implemented with firmware embedded TCU. As the master clutch engages along the predetermined speed trajectory, it can be concluded that the shift quality can be managed by a shift time control parameter. By extending the proposed feedback algorithm for neutral-into-gear shift to gear change and shuttle shift, it is expected that the quality of the shift can be improved.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.1
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• pp.97-110
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• 2019

Recently, the 4th Industrial Revolution has been emerged and various products are developed and commercialized in preparation of the communication failure. Many solutions are underway in Back-Up Network for IDC Servers, but not in the personal or sensor for low-power system use. Therefore we used the OpenWRT Firmware in Raspberry Pi which can be easily obtained in online market, and it created a low-power load balancer. Therefore, we developed the device that uses LTE Antenna based on USB Interface for communication fault notification and important data. The equipment used in this paper is easy to buy in online shop for anyone. Also, it can be applied in other vendors' boards by using USB. We hope that this paper will contribute to the stability of individual sensor networks.

• Journal of Advanced Navigation Technology
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• v.23 no.4
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• pp.316-321
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• 2019

In this paper, by applying the constant current principle we develop an impedance measurement system which can measure the high precision impedance of various electric materials by using microprocessor. This measurement system board has an interface device for acquiring digital data from an external device including an impedance measuring device, and system software is also developed by a firmware program executed on such an embedded board. It can measure the high precision impedance of a specific band with 1/32768 precision by using 15-bit ADC(analog to digital converter) and calculate it to the five digits to the right of the decimal point(fraction part). Data is transmitted through a USB interface of a general computer and a measuring device to manage digital data. An impedance measurement system equipped with a communication function capable of a more general and easy-to-use interface than other equipment is developed and verified.

• Convergence Security Journal
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• v.21 no.2
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• pp.29-35
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• 2021

UART (Universal asynchronous receiver/transmitter) is a hardware device that converts data into serial format and transmits it, and is widely used for system diagnosis and debugging in most embedded systems. Hackers can access system memory or firmware by using the functions of UART, and can take over the system by acquiring administrator rights of the system. In this paper, we studied secure UART to protect against hacker attacks through UART. In the proposed scheme, only authorized users using the promised UART communication protocol are allowed to access UART and unauthorized access is not allowed. In addition, data is encrypted and transmitted to prevent protocol analysis through sniffing. The proposed UART technique was implemented in an embedded Linux system and performance evaluation was performed.

• Journal of the Institute of Convergence Signal Processing
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• v.21 no.1
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• pp.38-48
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• 2020

In order to inspect the existing or newly constructed ship's hull, a professional diver directly inspects the ship's bottom of the water. However, since it is a work done by people, there are many dangers such as human casualties and crashes. To solve this problem, it is necessary to develop underwater drones for ship inspection for visual inspection. The technology applied to underwater drones, the use and manufacturing process of each component, and the method of manufacture such as firmware development were described, and the difference was compared by measuring the drone's own driving ability and driving ability using crawler under water, and the location tracking device test confirmed the error from the actual location. It is estimated that the use of underwater drones produced through this research will prevent human casualties and achieve economic effects and stability.