• 제목/요약/키워드: Able researchers

검색결과 341건 처리시간 0.028초

FPGA를 이용한 멀티레벨 스위칭 함수 구현 방법 (Method of Multi-level Switching Function based on FPGA)

  • 이화춘;송지석;박성준;이민중
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2008년도 추계종합학술대회 B
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    • pp.195-198
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    • 2008
  • 최근 태양광 발전시스템 등 낮은 전압을 발생하는 전원소스를 이용하여 높은 승압효과를 얻기 위한 멀티레벨 인버터에 대한 관심이 높아지고 있다. 본 논문은 FPGA 기반 멀티레벨 인버터용 스위칭 함수를 구현하고자 한다. FPGA는 프로그램 가능한 로직 디바이스로써 풀 디지털 스위칭함수를 구현하는 효율적이다. 본 논문에서는 FPGA 기반 스위칭 함수를 구현하기 위해서 마이크로프로세서로부터 출력되는 클럭과 동기신호로 독립적으로 구동이 되도록 하였다.

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열전소자를 이용한 BIPV 모듈의 냉각시스템 개발 (Cooling System Development of BIPV Module Using Thermoelectron)

  • 최정식;고재섭;정동화
    • 전기학회논문지
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    • 제57권9호
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    • pp.1555-1562
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    • 2008
  • This paper presents a cooling system using thermoelectron for improving the output of BIPV module. The temperature characteristic in regard to improving the output of BIPV system has rarely been studied up to now but some researchers only presented the method using a ventilator. The cooling system efficiency of BIPV module applied to a ventilator mainly depends on the weather such as wind, insolation etc. Because the cooling system of BIPV module using a ventilator is so sensitive, that is being set off by wind speed at all time but is unable to operate in the NOCT(Nominal Operating Cell Temperature) which is able to make the maximum output. The paper presents the cooling system using thermoelectron so as to solve such problems. The temperature control of thermoelectron can be controlled independently in the outside environment because that is performed by micro-controller. The temperature control of thermoelectron, also, can be operated around NOCT through algorism of the temperature control. Therefore, outputs of the whole system increase and the efficiency rises. The paper demonstrates the validity of proposed method by comparing the data obtained through a experiment of the cooling method of BIPV using a ventilator and proposed thermoelectron.

Audio Data Hiding Based on Sample Value Modification Using Modulus Function

  • Al-Hooti, Mohammed Hatem Ali;Djanali, Supeno;Ahmad, Tohari
    • Journal of Information Processing Systems
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    • 제12권3호
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    • pp.525-537
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    • 2016
  • Data hiding is a wide field that is helpful to secure network communications. It is common that many data hiding researchers consider improving and increasing many aspects such as capacity, stego file quality, or robustness. In this paper, we use an audio file as a cover and propose a reversible steganographic method that is modifying the sample values using modulus function in order to make the reminder of that particular value to be same as the secret bit that is needed to be embedded. In addition, we use a location map that locates these modified sample values. This is because in reversible data hiding it needs to exactly recover both the secret message and the original audio file from that stego file. The experimental results show that, this method (measured by correlation algorithm) is able to retrieve exactly the same secret message and audio file. Moreover, it has made a significant improvement in terms of the following: the capacity since each sample value is carrying a secret bit. The quality measured by peak signal-to-noise ratio (PSNR), signal-to-noise ratio (SNR), Pearson correlation coefficient (PCC), and Similarity Index Modulation (SIM). All of them have proven that the quality of the stego audio is relatively high.

선도기술개발사업(G7)의 정책결정 과정 분석: 범부처간 추진 과정 및 민간 전문가 역할을 중심으로 (Analysis for the Policy Making Process of G7 Project in 1990s)

  • 이찬구
    • 기술혁신연구
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    • 제16권2호
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    • pp.167-200
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    • 2008
  • This work firstly aims to analyse how the policy makers had been able to sort out the two policy issues, 'how did the MOST establish the inter-departmental project' and 'why did the MOST give a legal power to the private experts', in the process of policy making for Highly Advanced National(HAN) project, called G7 Project, which had been implemented for 10 years in 1990s. Then, this will discuss the policy implications available to the similar policy areas in the future. The result shows that the agenda setting of the G7 Project, one of the successful national R&D projects in Korea, had been initiated by a few leaders who had have the perspective of pioneer. In addition, this explains that private experts had more played than civil servant did in the process of policy formation, which had been backed up by the R&D plannin4g system then introduced in R&D management process for the frist time. This case study will provide policy makers with the opportunities to remind 'the necessities of the policy management by the system not actors', 'more effective management of distribution policy' and 'the better role of related experts in the policy making process'. Also, above issues will make both the practitioners and the researchers again consider how to improve the rationality and effectiveness of the policy making process in the field of science and technology.

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고체상 나노구멍을 이용한 DNA 염기서열 분석기술 (DNA Sequencing Analysis Technique by Using Solid-State Nanopore)

  • 김태헌;박정호
    • 센서학회지
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    • 제21권5호
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    • pp.359-366
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    • 2012
  • Nanopore DNA sequencing is an emerging and promising technique that can potentially realize the goal of a low-cost and high-throughput method for analyzing human genome. Especially, solid-state nanopores have relatively high mechanical stability, simple surface modification, and facile fabrication process without the need for labeling or amplification of PCR (polymerized chain reaction) in DNA sequencing. For these advantages of solid-sate nanopores, the use of solid-state nanopores has been extensively considered for developing a next generation DNA sequencing technology. Solid-state nanopore sequencing technique can determine and count charged molecules such as single-stranded DNA, double-stranded DNA, or RNA when they are driven to pass through a membrane nanopore between two electrolytes of cis-trans chambers with applied bias voltage by measuring the ionic current which varies due to the existence of the charged particles in the nanopore. Recently, many researchers have suggested that nanopore-based sensors can be competitive with other third-generation DNA sequencing technologies, and may be able to rapidly and reliably sequence the human genome for under $1,000.

소형 다중분광 항공촬영 시스템(PKNU 3호) 개발에 관한 연구 (Research for development of small format multi -spectral aerial photographing systems (PKNU 3))

  • 이은경;최철웅;서영찬;조남춘
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 추계학술발표회 논문집
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    • pp.143-152
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    • 2004
  • Researchers seeking geological and environmental information, depend on remote sensing and aerial photographic datum from various commercial satellites and aircraft. However, adverse weather conditions as well as equipment expense limit the ability to collect data anywhere and anytime. To allow for better flexibility in geological and environmental data collection, we have developed a compact, multi-spectral automatic Aerial Photographic system (PKNU2). This system's Multi-spectral camera can record visible (RGB) and infrared (NIR) band (3032*2008 Pixels) images Visible and infrared band images were obtained from each camera respectively and produced color-infrared composite images to be analyzed for the purpose of the environmental monitoring. However this did not provide quality data. Furthermore, it has the disadvantage of having the stereoscopic overlap area being 60% unsatisfied due to the 12 seconds of storage time of each data The PKNU2 system in contrast, photographed photos of great capacity Thus, with such results, we have been proceeding to develop the advanced PKNU2 (PKNU3) system that consists of a color-infrared spectral camera that can photograph in the visible and near-infrared bands simultaneously using a single sensor, a thermal infrared camera, two 40G computers to store images, and an MPEG board that can compress and transfer data to the computer in real time as well as be able to be mounted onto a helicopter platform.

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A Novel Technique for Human Traffic based Radio Map Updating in Wi-Fi Indoor Positioning Systems

  • Mo, Yun;Zhang, Zhongzhao;Lu, Yang;Agha, Gul
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권5호
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    • pp.1881-1903
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    • 2015
  • With the fast-developing of mobile terminals, positioning techniques based on fingerprinting method draws attention from many researchers even world famous companies. To conquer some shortcomings of the existing fingerprinting systems and further improve its performance, we propose a radio map building and updating technique, which is able to customize the spatial and temporal dependency of radio maps. The method includes indoor propagation and penetration modeling and the analysis of human traffic. Based on the combination of Ray-Tracing Algorithm, Finite-Different Time-Domain and Rough Set Theory, the approach of indoor propagation modeling accurately represents the spatial dependency of the radio map. In terms of temporal dependency, we specifically study the factor of moving people in the interest area. With measurement and statistics, the factor of human traffic is introduced as the temporal updating component. We improve our existing indoor positioning system with the proposed building and updating method, and compare the localization accuracy. The results show that the enhanced system can conquer the influence caused by moving people, and maintain the confidence probability stable during week, which enhance the actual availability and robustness of fingerprinting-based indoor positioning system.

하나의 카메라를 이용한 인터렉티스 3D 집적 영상 시스템 (Interactive 3D Integral Imaging System using Single Camera)

  • 신동학;김은수
    • 한국통신학회논문지
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    • 제33권10C호
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    • pp.829-835
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    • 2008
  • 최근 무안경식 3D 디스플레이 방법으로 잘 알려진 3D 집적 영상 시스템에 대한 연구가 활발히 진행되고 있다. 이 3D 집적 영상 기술은 연속적인 시점, 완전 시차와 풀 칼라 영상을 공중에 표현하는 유망한 기술이다. 본 논문에서는 한 대의 카메라를 이용한 새로운 형태의 인터렉티스 3D 집적 영상 시스템을 제안한다. 이 장치는 기존의 3D 집적 영상 디스플레이 시스템에 단순한 한 대의 카메라를 추가적으로 사용하여 유저 인터페이스가 구현될 수 있다. 제안하는 시스템의 가능성을 보이기 위해서, 실험적인 장치 구현을 수행하고 기초적인 실험 결과를 보고한다. 우리가 아는 한 제안하는 방법은 3D 집적 영상 시스템에 최초로 인터렉션 기능을 추가한 것이다.

지진 재해 위험도 평가 분석 도구 사례 분석 연구 (A Review and Analysis of Earthquake Disaster Risk Assessment Tools and Applications)

  • 채수성;서동준
    • 디지털콘텐츠학회 논문지
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    • 제19권5호
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    • pp.899-906
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    • 2018
  • 재난피해 손실의 최소화를 위하여 관련 정보의 체계적인 구축과 피해를 정량적으로 분석하는 것은 재난 예방, 대응 복구 등의 재난관리 전 단계에 있어서 매우 중요하다. 우리나라를 비롯한 세계 각국에서는 해당 지역 또는 특정 환경에 적합한 인벤토리, 취약성 정보, 재해 위험지도 등의 정보 구축 연구뿐만 아니라 경제적 손실, 인명 손실, 건물 손상도 추정, 피난처 분석 등을 포함한 재해 피해 평가 및 분석 도구 개발에 많은 노력을 기울이고 있다. 본 논문은 지진 재해를 중심으로 대표적인 지진 피해 위험 분석 도구를 선정하고, 이를 비교 분석하였다. 이를 통해, 관련분야의 연구자들뿐만 아니라 재난 관리 의사 결정자 등에게 적합한 분석도구의 선정, 응용 소프트웨어의 개발 및 확장 등에 있어서 유용한 정보를 제공할 수 있을 것이다.

Product Characteristics, Market Competitive Strategies, and SMEs Performance: Testing Their Relationships

  • HARJADI, Dikdik;YUNIAWAN, Ahyar;ABDURRAHMAN, Agus;DANANJOYO, Radyan;FILATROVI, Eldes Willy;ARRANIRI, Iqbal
    • The Journal of Asian Finance, Economics and Business
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    • 제7권10호
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    • pp.613-620
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    • 2020
  • COVID-19 pandemic has made the economy in Indonesia sluggish, especially Small and Medium Enterprises (SMEs). Simultaneously, the SMEs existence in Indonesia is fundamental and considered important by the government since it is able to assist numerous laborers and become an income source for the lower and middle classes of the community. The productivity of SME in a region will undeniably influence the availability of job and, of course, reduce the number of unemployed. Therefore, in this study, the researchers looked at how to improve SMEs performance to continue to exist amid the COVID-19 pandemic, by identifying the relationships between product characteristics, market competitive strategies, and the performance of SMEs. The research was done on SMEs in West Java, Indonesia. The example employed was Batik SMEs in Cirebon with at least 10 years in existence, and the total number of these SMEs was 165. As the basis of a quantitative approach, this study employed survey instruments by distributing a questionnaire. In analyzing the data, it utilized the structural equation modeling (SEM). The result showed a significant relationship between Product Characteristics, Market Competitive Strategy, and Price and Product Success Rate on SMEs Performance. This study's findings contribute to the SMEs performance literature.