• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.5
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• pp.975-981
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• 2017

In this paper, we propose a method for efficient use of energy when using flash device in WSN environment. Typical Flash devices have a drawback to be an energy efficient storage media in the energy-constrained WSNs due to the high standby energy. An energy efficient approach to deploy Flash devices into WSNs is simply turning the Flash device off whenever idle. In this regard, we make the simple but ideal approach realistic by removing these two obstacles by exploiting nonvolatile RAM (NVRAM), which is an emerging memory technology that provides both non-volatility and byte-addressability. Specifically, we make use of NVRAM as an extension of metadata storage to remove the FTL metadata scanning process that mainly incurs the two obstacles. Through the implementation and evaluation in a real system environment, we verify that significant energy savings without sacrificing I/O performance are feasible in WSNs by turning off the Flash device exploiting NVRAM whenever it becomes idle. Experimental results show that the proposed method consumes only about 1.087% energy compared to the conventional storage device.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.381-385
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• 2010

An aging Society solitary life old mans are increasing. The nurses have to visit old mans and must confirm their disease, because they do not act well. It is very difficult to take care old man, because the number of Nurses are small. This problem is solved by collection of data about condition of old mans from long distance. Data communication with Ethernet have benefit to collection of measurement of old man's condition. The Data storage system an long distance place are storaged data and after several day data was transmitted to the DB over the Ethernet. For Miniaturization of such system the system must be OS-less Embedded Ethernet Server system. Such system manages the file management system only with H/W. The Storage device is used SD-card. SD Card is small size and operates with small power. By using 512MB sd memory card, it is possible to storage during 5~6 years, 10 byte of temperature value per second. In this paper, we make a Embedded Ethernet Server using W3100A, Atmega128 MCU and data stroage device using SD-Card. This system operates with O/S-less Embedded Ethernet Server. We talk about file System, Storage and Ethernet. We explained about MCU Atmega128, Interface between LAN LSIand W3100A, Interface between W3100A and Phyceiver RTL8201, data I/O between MCU and SD-Card and File System. We shows the experiment device and result of monitoring.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.1
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• pp.17-24
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• 2017

As the prevalence of removable device, critical intelligences are often stored in the removable device. For that reason, in seizure and search, the removable device became a important evidence of while it could be has a salient key for prove a crime. When we acquired a removable device for proof, we image it by a imaging device or software with a write protection. However, these are high-priced exclusive equipments and sometimes it could be out of order. In addition, we found that some secure USB and inbuilt vaccine USB are failed to connect to the imaging device. Therefore, in this paper, we provide a suitable digital evidence collection procedure for real.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.496-498
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• 2003

접미사 배열은 긴 문자열에 대해 효율적인 문자열 검색을 가능하게 하는 자료구조이다. 접미사 배열은 문자열의 접미사들의 사전식 정렬순서를 배열로 저장한다. 비슷한 효과를 가진 접미사 트리에 비해서 접미사 배열은 저장 공간을 적게 차지하기 때문에 생명정보과학의 염기 서열 등 큰 크기의 문자열의 처리에 더욱 유리하다. 본 논문에서는 2003년에 발표된 Ko-Aluru, K$\square$rkk$\square$inen-Sanders 및 기존의 Manber-Myers 등 세 개의 접미사 배열 생성 알고리즘들의 염기 서열 입력 자료에 대한 실행 시간 및 기억 장치 사용량을 실험을 통해 비교한다. 특히 Ko-Aluru와 K$\square$rkk$\square$inen-Sanders 알고리즘은 실행 시간 및 저장 공간의 이론적인 복잡도가 O(n)으로 동일하기 때문에 실험을 통해서 계산 복잡도에 숨어있는 상수를 비교한다. 실험 결과 K$\square$rkk$\square$inen-Sanders 알고리즘이 가장 효율적임을 보인다.

• Journal of the KSME
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• v.49 no.11
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• pp.45-51
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• 2009

한국원자력연구원의 다목적 연구용 원자로, 하나로는 중성자 이용 물성 연구 등 다양한 분야에 사용되며, 중성자는 녹색기술 관련 소재의 생산과 특성 분석에 매우 유용한 도구이다. 중성자 도핑을 이용하여 생산되는 반도체는 그린 카에 사용되는 전력 소자에 활용되고 있다. 중성자 산란 실험 장치들은 이차전지 재료와 수소저장 물질의 물성 연구에 활용되고 있다. 중성자 비파괴 검사 장치는 연료전지의 성능 연구에 활용되고 있다. 고속중성자를 이용하여 스위칭 소자의 특성을 개선하는 기술과 장치가 구축되면 전력 소자의 효율 증대에 기여할 것이다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.11
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• pp.937-942
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• 2003

In the present study, low-temperature low-pressure refrigerant storage method is proposed to achieve higher cooling capacity during a short period of time than that of a compressor in steady operation. Experimental apparatus was designed and set up to analyze the performance of the new-conceptual cooling system. Two reservoirs for sequential storage of refrigerant were used in the cooling system. Several on/off solenoid valves were installed for control of refrigerant flow. From the experimental results, the initial rapid cooling by low temperature low-pressure refrigerant storage method was ascertained for successful operation. This rapid cooling methodology shall be useful for other low-capacity refrigeration system.

• Fire Science and Engineering
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• v.13 no.3
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• pp.19-26
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• 1999

$CO_2$ extinguishing system is the most $\phi$pular among the gas extinguishing system. $CO_2$ is usually stored with liquified state. But, it gasifies at the tip of nozzle when $CO_2$ was released through the pipe and head. A ro$\alpha$n temperature is very low when $CO_2$ was released. So electrical instrument, magnetic storage equipment and memory semiconductor are electrically or physically injured by cooling effect in a few minutes. So, we intend to find out temperature profile and electrical damage in compartment area, and supply basic d data for research and making standards and code through the full scale experiment. As result of experiment on the damage due to cooling effect from $CO_2$ extinguishing system, i instantaneous discharging temperature. was $-82.5^{\circ}C$ in average. An average temp. in the compartment after discharging $CO_2$ was $-40^{\circ}C$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.11
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• pp.1330-1336
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• 2019

As the Fourth Industrial Revolution era began, a variety of devices are running on the cloud. These various devices continue to generate various types of data or large amounts of multimedia data. To handle this situation, a large amount of storage is required, and big data technology is required to process stored data and obtain accurate information. NAS (Network Attached Storage) or SAN (Storage Area Network) technology is typically used to build high-speed, high-capacity storage in a network-based environment. In this paper, we propose a method to construct a mass storage device using Network-DAS which is an extension technology of DAS (Direct Attached Storage). Benchmark experiments were performed to verify the scalability of the storage system with 76 HDD. Experimental results show that the proposed high performance mass storage system is scalable and reliable.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.3
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• pp.188-198
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• 2010

Recently, as the demand of the environmental-friendly energy storage system such as an electric double-layer condenser increases, that of the bidirectional charger/discharger for the systems also increases. However, when charging/discharging mode-change occurs, the charger/discharger employing a bi-directional DC-DC converter with a commercialized analog controller has a complex circuit scheme, and a poor transient response. On the other hand, if a single digital controller is used for the bi-directional mode, the system performances can be improved by application of an advanced power-processing algorithm. In the paper, an environmental-friendly power storage systems including an Electric Double Layer Capacitor(EDLC) banks were developed with a bi-directional buck-boost converter and a digital signal processor (TMS320F28335). A simulation test-bed was realized and tested by MATLAB Simulink, and the hardware experiment was performed which shows that the dynamic response was improved such as the simulation results.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.11a
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• pp.30-33
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• 2007

본 논문에서는 모바일폰을 통한 시맨틱 검색 및 개인 기호정보를 사용한 검색 결과의 필터링이 가능한 시스템을 제안 하고자 한다. 시스템에서는 모바일 컨텐츠와 웹 컨텐츠의 검색 연동, 사용자 기호정보의 유 무선 장치의 공유 및 유 무선 장치간 검색 결과의 공유를 지원한다. 모바일폰의 컴퓨팅 능력을 고려해 모바일폰에는 사용자 인터페이스만을 유지 하도록 한다. 모바일폰을 통한 시맨틱 검색을 지원하기 위해 시스템은 실험적으로 뉴스 도메인에 국한된 카테고리에 대한 분류 체계 온톨로지를 구축하며, 각 카테고리간 관계를 설정 한다. 또한, 개인 기호정보를 통한 검색 결과의 필터링을 위해 사용자 기호정보를 XML 형태의 벡터 모델로 유지하며, 이는 서버의 데이터베이스에 각 사용자 계정으로 저장하고 공유한다. 모바일폰의 여러 단점을 극복하고 장점을 극대화 하기 위해 검색 결과를 서버에 저장하고 이를 유 무선 장치간 상호 공유 할 수 있도록 한다. 본 논문에서는 시스템의 아키텍처와 구성 및 주요 기능에 대해서 기술하고자 한다.