• Journal of Computing Science and Engineering
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• 제3권3호
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• pp.181-194
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• 2009

Flash memory is increasingly being used in a wide range of storage applications because of its low power consumption, low access latency, small form factor, and high shock resistance. However, the current platforms for flash memory software development do not meet the ever-increasing requirements of flash memory applications. This paper presents three different hardware platforms for flash memory/NVRAM (non-volatile RAM) software development that overcome the limitations of the current platforms. The three platforms target different types of host system and provide various features that facilitate the development and verification of flash memory/NVRAM software. In this paper, we also demonstrate the usefulness of the three platforms by implementing three different types of storage system (one for each platform) based on them.

• 한국정보통신학회논문지
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• 제17권5호
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• pp.1145-1153
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• 2013

Android 모바일 플랫폼은 플랫폼에 설치된 모든 어플리케이션들의 클래스(class) 파일들을 복사하여 하나의 디렉터리에 보관하고, 해당 디렉터리에서 메모리 맵 파일(memory-mapped file) 방식으로 참조함으로써 서비스 라이브러리를 플랫폼에 추가하기 위해서는 플랫폼의 바이너리(binary) 이미지를 반드시 새롭게 생성하여 플랫폼을 교체해야만 한다. 또한, 이러한 메모리 맵 파일 방식의 참조는 어플리케이션이 참조하는 라이브러리가 중복될 경우 해당 디렉터리에서도 중복되어 포함되므로 디바이스의 저장 공간 낭비를 불러오게 된다. 따라서, Android 모바일 플랫폼상에서 동작하는 각 어플리케이션들의 서비스 라이브러리를 공유 라이브러리 형태로 관리하며, 플랫폼의 버전 관리 및 기능 추가 및 변경을 실시간 및 동적으로 지원할 수 있는 Android 플랫폼용 동적 재구성 기법이 필요하다. 본 논문에서는 Android 모바일 플랫폼을 대상으로 하여, 동적으로 서비스 라이브러리를 추가할 수 있는 플랫폼 동적 재구성 기법을 제안한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권11호
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• pp.5234-5251
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• 2018

It is well-known that virtualization technology can bring many benefits not only to users but also to service providers. From the view of system security and resource utility, higher resource sharing degree and higher system reliability can be obtained by the introduction of virtualization technology in distributed cloud. The small size time-sharing multiplexing technology which is based on virtual machine in distributed cloud platform can enhance the resource utilization effectively by server consolidation. In this paper, the concept of memory block and user satisfaction is redefined combined with user requirements. According to the unbalanced memory resource states and user preference requirements in multi-virtual machine environments, a model of proper memory resource allocation is proposed combined with memory block and user satisfaction, and at the same time a memory optimization allocation algorithm is proposed which is based on virtual memory block, makespan and user satisfaction under the premise of an orderly physical nodes states also. In the algorithm, a memory optimal problem can be transformed into a resource workload balance problem. All the virtual machine tasks are simulated in Cloudsim platform. And the experimental results show that the problem of virtual machine memory resource allocation can be solved flexibly and efficiently.

• 대한조선학회논문집
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• 제41권5호
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• pp.1-7
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• 2004

The Spar platform with deep draft is characterized as effective structure in extreme wave condition, which has larger natural period than that of waves in sea. In this paper, the time domain simulation of motion responses of Spar with catenary mooring line is presented in irregular waves. The memory effect is modeled by added mass at infinite frequency and convolution integrals in terms of wave damping coefficients. The added mass, wave damping coefficients and wave exciting forces are obtained from three-dimensional panel method in the frequency domain. The motion equations are consisted of forces for inertia, memory effect, hydrostatic restoring, wave exciting and mooring line. The forces of mooring line are modeled as quasi-static catenary cable.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.167-171
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• 2004

The Spar platform with deep draft is characterized as effective structure in extreme wave condition, which has larger natural period than that of waves in sea. In this paper, the time simulation of motion responses of Spar with catenary mooring line is presented in irregular waves. The memory effect is modeled by added mass at infinite frequency and convolution integrals in terms of wave damping coefficients. The added mass, wave damping coefficients and wave exciting forces are obtained from three-dimensional panel method in the frequency domain. The motion equations are consisted of forces for inetia, memory effect, hydrostatic restoring, wave exciting and mooring line. The forces of mooring line are modeled as quasi-static catenary cable.

• 한국산업정보학회논문지
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• 제21권3호
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• pp.13-19
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• 2016

최근에 실시간 처리를 위해 메모리 기반의 빅데이터 처리 프레임 워크인 스파크가 널리 사용되고 있다. 스파크는 프로그램이 필요로 하는 중간 데이터를 모두 메모리에 올려놓아, I/O 수행을 최소화함으로써 빠른 응답을 가져올 수 있다. 그러나 응용프로그램의 메모리 사용량이 클러스터의 실제 메모리의 량보다 많을 경우, 최적의 성능을 기대하기 어렵다. 본 논문에서는 메모리 사용량이 많은 페이지랭크 응용 프로그램에서 병목이 되는 현상을 실험을 통해 그 요인에 대해 분석하고, 스파크와 함께 타키온을 구성해서 메모리의 효율적 사용을 통해 병목의 요인을 해결하여 18%의 성능향상을 하였다.

• 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.)

• 전기학회논문지
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• 제66권12호
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• pp.1792-1798
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• 2017

Event Data Recorder(Car Black-Box) with WiFi dongle have been released, and the platform of the majority is the Linux platform. This is because the platform development is possible in little investment cost by reducing the source licensing costs by taking advantage of the open source. But utilizing Linux platform has the limitations of boot-up time and consuming processing power due to the limitation of battery capacity, to be cost-competitive to minimize the use of memory. In this paper, the real-time operating system(RTOS) is utilized to optimize these portions. MP4 encoder and Muxer are developed to be about ten seconds boot up and minimized memory. It has the advantages of operating at lower power consumption than the Linux utilizing WiFi dongle. Utilizing a WiFi dongle is to provide a progressive download feature on smart phones to lower product prices. But RTOS has the weakness in WiFi. Porting TCP /IP, Web and DHCP server and combination with the USB OTG Host interface by implementing the protocol stack are developed for WiFi. And also SPI NOR flash memory is utilized for faster boot time and cost reductions, low processing power to be consume. As the results, the developed proved the 10 seconds booting time, 24 frame rate/sec. and 10% lower power consumption.

• 대한임베디드공학회논문지
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• 제8권5호
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• pp.235-242
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• 2013

Recently, the number of automotive electrical and electronic system has been increased because the requirements for the convenience and safety of the drivers and passengers are raised. In most cases, the data for controlling the various sensors and automotive electrical and electronic system used in runtime should be stored on the internal or external non-volatile memory of the ECU(Electronic Control Units). However, the non-volatile memory has a constraint with write limitation due to the hardware characteristics. The limitation causes fatal accidents or unexpected results if the non-volatile memory is not managed. In this paper, we propose a management scheme for using non-volatile memory to prolong the writing times based on AUTOSAR(AUTOmotive Open System Architecture) platform. Our proposal is implemented on the CDD(Complex Device Driver) and uses an algorithm which swaps a frequently modified block for a least modified block. Through the development of the prototype, the proposed scheme extends the lifetime of non-volatile memory about 1.08 to 2.48 times than simply using the AUTOSAR standard.

• 한국멀티미디어학회논문지
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• 제6권7호
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• pp.1200-1208
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• 2003

자바카드 기술은 스마트카드나 메모리 제한적인 장치에서 자바 프로그래밍 언어로 작성된 응용프로그램을 동작 가능하게 한다. 자바카드 기술은 높은 안전성, 이식성, 다중의 응용프로그램을 관리하고 저장하는 기능을 제공한다. 그러나 자바카드 플랫폼의 제한적인 메모리 자원은 다양한 용도로 자바카드가 보급되는데 저해 요인으로 작용하고 있다. 따라서 본 논문에서는 자바카드의 효율적인 메모리 사용을 위해서 바이트코드 최적화 알고리즘을 제안한다. 이 알고리즘은 예외처리 구문 try-catch-finally에서 catch절의 매개변수에 대한 기억장소를 공유하게 함으로써 생성되는 바이트코드의 크기를 줄일 수 있다.