• 대한임베디드공학회논문지
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• 제2권4호
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• pp.260-273
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• 2007

The wireless sensor network (WSN) nodes are required to operate for several months with the limited system resource such as memory and power. The hardware platform of WSN has 128Kbyte program memory and 8Kbytes data memory. Also, WSN node is required to operate for several months with the two AA size batteries. The MAC, Network protocol, and small application must be operated in this WSN platform. We look around the problem of memory and power for WSN requirements. Then, we propose a new computing model of system software for WSN node. It is the Atomic Object Model (AOM) with Dual Priority Scheduling. For the verification of model, we design and implement IEEE 802.15.4 MAC protocol with the proposed model.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1826-1829
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• 2005

Recent advancement in wireless communications and electronics has enabled the development of low power sensor network. Wireless sensor network are often used in remote monitoring control applications, health care, security and environmental monitoring. Wireless sensor networks are an emerging technology consisting of small, low-power, and low-cost devices that integrate limited computation, sensing, and radio communication capabilities. Sensor network platform for health care has been designed, fabricated and tested. This system consists of an embedded micro-controller, Radio Frequency (RF) transceiver, power management, I/O expansion, and serial communication (RS-232). The hardware platform uses Atmel ATmega128L 8-bit ultra low power RISC processor with 128KB flash memory as the program memory and 4KB SRAM as the data memory. The radio transceiver (Chipcon CC1000) operates in the ISM band at 433MHz or 916MHz with a maximum data rate of 76.8kbps. Also, the indoor radio range is approximately 20-30m. When many sensors have to communicate with the controller, standard communication interfaces such as Serial Peripheral Interface (SPI) or Integrated Circuit ($I^{2}C$) allow sharing a single communication bus. With its low power, the smallest and low cost design, the wireless sensor network system and wireless sensing electronics to collect health-related information of human vitality and main physiological parameters (ECG, Temperature, Perspiration, Blood Pressure and some more vitality parameters, etc.)

• International Journal of Internet, Broadcasting and Communication
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• 제9권1호
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• pp.29-34
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• 2017

Over the past several decades, embedded system and flight control computer technologies have been evolved to meet the diverse needs of the mobile device market. Current embedded systems are at the heart of technologies that can take advantage of small-sized specialized hardware while still providing high-efficiency performance at low cost. One of these key technologies is multiple memory banks. For example, a dual memory bank can provide two times more memory bandwidth in the same memory space. This benefit take lower cost to provide the same bandwidth. However, there is still few software technologies to support the efficient use of multiple memory banks. In this study, we present a technique to efficiently exploit multiple memory banks by software support. Specifically, our technique use an interference graph to optimally allocate data to different memory banks by an optimizing compiler. As a result, the execution time can be improved upto 7% with the proposed technique.

• 한국멀티미디어학회논문지
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• 제7권8호
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• pp.1058-1065
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• 2004

단순 모니터에서 CPU, 메모리, 그리고 하드디스크를 갖춘 셋탑박스에 이르기까지 내장형 시스템은 다양한 응용에 사용되고 있다. 특히 휴대용 또는 소형기기에 멀티미디어를 서비스하는 경우가 증가하고 있고 이들 시스템에는 내장형 운영체제가 탑재되고 있다. 본 논문에서는 멀티미디어 서비스를 위한 내장형 리눅스가 탑재된 임베디드 시스템에서 응용 프로그램과 운영체제 커널사이의 메모리 복사 요구를 감소시키는 Null copy기법을 제안한다. 저성능의 컴퓨팅 파워 및 저용량의 메모리를 가진 내장형 시스템에서 연속 미디어를 네트워크를 통해 실시간으로 전송하고자 할 때 Null copy 기법은 시스템의 QoS를 만족시킬 수 있다. 웹 카메라를 내장형 리눅스 개발 보드에 장착하여 영상 전송 환경을 구축한 결과 Null copy 기법은 CPU 이용률 및 마감시간 실패측면에서 기존 커널에 비해 우수한 성능을 나타내었다.

• 전기학회논문지P
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• 제52권2호
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• pp.85-90
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• 2003

This paper has presented the efficient implementation of MPEG-4 simple profile video decoder, which is used as video compression standard in mobile video communication. We have used the ARM9 processor in implementing this MPEG-4 simple profile, which requires much processing power and low power implementation. At first we implemented with C-language under the PC environment with ADS(ARM Developer Suite) environment, and then we have tried to reduce a clock cycle for a power consumption optimization through conversion an assembly language for C-code partly. We have verified the processor is operated at 22.47MHz operation after optimization, but 148MHz before optimization.

• 한국전기전자재료학회논문지
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• 제33권4호
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• pp.326-330
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• 2020

Small-scale production control systems for smart manufacturing are becoming increasingly necessary as the manufacturing industry seeks to maximize manufacturing efficiency as the demand for customized product production increases. Correspondingly, the development of an embedded system to realize this capability is becoming important. In this study, we developed an embedded system based on an open source system that is cheaper than a widely applied programmable logic controller (PLC)-based production control system that is easier to install, configure, and process than a conventional relay control panel. This embedded system is system is based on a low-power, high-performance Cortex M4 processor and can be applied to smart manufacturing. It is designed to improve the development environment and compatibility of existing PLCs, control small-scale production systems, and enable data collection through heterogeneous communication. The real-time response characteristics were confirmed through an operation test for input/output control and data collection, and it was confirmed that they can be used in industrial sites.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2159-2163
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• 2003

Hand carried computing machinery and tools have been developed into an embedded system which the small footprint operating system is contained internally. Windows CE which is one of imbedded operating system is a lightweight, multithreaded operating system with an optional graphical user interface. Its strength lies in its small size, its Win32 subset API, and its multiplatform support. Therefore we choose to port this OS on Arm based board that is provided high performance, low cost, and low power consumption. In this paper, we describe the architecture of ARM based board, the feature of Windows CE, techniques and steps involved in this porting process.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.641-644
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• 2008

본 논문은 지능형 임베디드 시스템의 GUI 구현에 관한 논문이다. 지능형 임베디드 시스템의 GUI 구현을 위해 사용된 X 윈도우 시스템과 그래픽 라이브러리의 구조 및 동작에 대해 논하고 지능형 임베디드 시스템의 X-시스템에 필요한 기능 및 구성 요소에 대해 조사 및 분석을 통한 리눅스 커널과의 동작 및 기능 검증 구현을 보인다. 저성능 및 저전력이며 고용량 메모리를 탑재한 임베디드 시스템의 하나인 지능형 임베디드 X-시스템에서 적용 가능하도록 요구되는 기능과 동작을 구현하고 소형 운영체제를 위한 GUI 개발에 적용 가능하다. 이러한 소형 운영체제 및 이를 위한 X-시스템은 지능형 개인정보서비스를 위한 임베디드 플랫폼 시스템으로써 개인용 정보의 지능형 서비스 기능을 지원하고 새로운 소형 운영체제를 탑재한 시스템의 개발에 적용 가능하다. 본 논문에서는 이러한 지능형 임베디드 X-시스템과 응용 소프트웨어 및 서비스 개발을 위한 GUI환경 구현에 대하여 기술한다.

• 대한임베디드공학회논문지
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• 제7권5호
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• pp.209-217
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• 2012

In the present, Wireless Sensor Network(WSN) has been used for the purpose of the military operation with surveillance systems and for collecting useful information from the natural environment. Basically, low-power, easy deployment and low cost are the most important factors to be deployed for WSNs. Lots of researches have been studied to meet those requirements, especially on the node capacity and battery lifetime improvements. Recently, the study of wireless mesh networks applied into the surveillance systems has been proceeded as a solution of easy deployment. In this paper, we proposed large-scale intelligent multi-layer surveillance systems based on QoS assuring Wireless Mesh Networks and implemented them in the real testbed environment. The proposed system explains functions and operations for each subsystem as well as S/W and H/W architectures. Experimental results are shown for the implemented subsystems and the performance is satisfactory for the surveillance system. We can identify the possibility of the implemented multi-layer surveillance system to be used in practice.

• 대한임베디드공학회논문지
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• 제11권1호
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• pp.1-8
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• 2016

We proposed a load unbalancing scheduling method for energy-efficient multi-core embedded systems considering DVFS (Dynamic Voltage/Frequency Scaling) power consumption and task characteristics. It is a new kind of scheduler which combines load balancing and load unbalancing technique. The purpose of the method is to effectively utilize energy without much effect in performance. In this paper, we conduct experiments on energy consumption and performance using the previous load balancing and unbalancing techniques and our proposed technique. The proposed technique reduced energy consumption more than 13.7% when compared to other algorithms. As a result, the proposed technique shows low energy consumption without much decline in the performance and is adequate for energy-efficient multi-core embedded systems.