• 한국멀티미디어학회논문지
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• 제23권2호
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• pp.293-300
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• 2020

Since the communication networks like the Internet collapses at disaster and calamity sites, a maintenance system that can be operated offline is required for the maintenance of various facilities. In this paper, we propose a system that memory tags attached on the facilities may transmit the emergency manual to a smart-phone, and the smart phone displays it off-line. The main issue is to design low energy mode memory tags. This study presents two kinds of methods and analyzes each's energy consumption mode. The first one is to develop memory tags by using one chip, and the next one is to design memory tags by forming multi-modules. Both ways show proper application fields under the low energy mode. This research selects the off-line maintenance system by using one chip design, and proposes the direction of contents for enhancing the effectiveness of the system. And we expect that this memory tags will be valuable for disaster scenes as well as battle fields.

• 대한조선학회논문집
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• 제44권6호
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• pp.657-665
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• 2007

The object of this paper is to describe the ubiquitous computing technologies for ship, which is produced and assembled by many steel blocks. It includes the testing of a 2.4GHz wireless communications platforms and radio-frequency identification technology with the blocks disturbing the wireless communication. The power line communication that is established in a ship already is also experimented for some data transfer. Also, possible application areas of the ubiquitous computing technology to ships are discussed. At last, the test bed copied from an actual vessel was installed and data acquisition tests were established using wire and wireless communication. In this paper, we implemented some ubiquitous computing technologies in the test bed simulating a ship environment and investigated the basic characteristics of ubiquitous computing technologies.

• 한국통신학회논문지
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• 제36권2C호
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• pp.93-98
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• 2011

현재 매우 빠른 속도로 늘어나고 있는 인터넷 수요를 충족시키기 위하여 새로운 통신 대안이 필요하다. 이런 대안들 중에 하나가 바로 광대역 고속 전력선 통신이다. 전력선 통신은 전력을 전달하는 도체에 신호를 같이 실어 보내는 통신 방법이다. 하지만 전력선을 그대로 사용한다는 단점 때문에 기존의 사용되는 통신 시스템과의 간섭이 발생한다. 이런 간섭을 제거하기 위하여 일반적인 방법으로는 Notch 필터를 주로 사용한다. 반면 다른 방법의 하나로 Wavelet OFDM이 사용된다. 본 논문에서는 Wavelet OFDM에서 사용되는 CMFB구조에 CIC 필터를 적용하여 그 부협의 값을 더욱 낮추어 성능을 높이는 방법을 제안한다.

• Journal of Multimedia Information System
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• 제6권1호
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• pp.23-30
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• 2019

A communications profile is a system that acquires information from communication links to an ambulance or other vehicle moving on a road and compiles a database based on this information. The equipment (six sets of HDTVs, fish-eye camera, satellite antenna with tracking system, and receiving power from the satellite beacon of the N-star) mounted on the roof of the vehicle, image data were obtained at Yokohama Japan. From these data, the polygon of the building was actually produced and has arranged on the map of the Geographical Survey Institute of a 50 m-mesh. The optical study (relationship between visibility rate and elevation angle) were performed on actual data taken by fish-eye lens, and simulated data by 3D-Map with polygons. There was no big difference. This 3D map system then predicts the communication links that will be available at a given location. For line-of-sight communication, optical analysis allows approximation if the frequency is sufficiently high. For non-line-of-sight communication, previously obtained electric power data can be used as reference information for approximation in certain cases when combined with predicted values calculated based on a 3D map. 3D maps are more effective than 2D maps for landing emergency medical helicopters on public roadways in the event of a disaster. Using advanced imaging technologies, we have produced a semi-automatic creation of a high-precision 3D map at Yokohama Yamashita Park and vicinity and assessed its effectiveness on telecommunications and ambulatory merits.

• 전력전자학회논문지
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• 제9권6호
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• pp.620-627
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• 2004

H-브릿지 멀티레벨 인버터는 여러 개의 단상 Power Cell을 직렬로 연결함으로써 저전압 전력용 반도체를 사용하여 고전압을 얻을 수 있고, 정현파에 가까운 출력전압 파형을 얻을 수 있는 멀티레벨 인버터 토폴로지이다. 본 논문은 산업현장에서 신뢰성을 인정받아 많이 사용되고 있는 직렬통신 방식의 일종인 CAN통신 인터럽터를 이용한 H-브릿지 멀티레벨 인버터 Power Cell의 PU 동기화 및 위상전이 방법에 관한 것이다. 제안된 방법의 주요 장점은 주제어기와 셀 제어기 사이에 직렬통신(CAN)을 사용함으로써 주제어기와 셀 제어기의 신호선의 단순화, 주제어기의 부담 감소, Power Cell의 모듈화, 셀 단위의 보호동작 용이, 확장성 향상 그리고 제어 신호 및 Power Cell의 신뢰성을 향상에 있다. 13레벨로 구성된 H-브릿지 멀티레벨 인버터 시험을 통해 제안된 방법의 타당성과 신뢰성을 입증하였다.

• 한국전자통신학회논문지
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• 제10권8호
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• pp.921-926
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• 2015

멀티 콘센트의 과전류로 인한 과열을 방지하기 위한 보호방식으로는 주로 금속바이메탈 방식, 스위칭회로 방식, 마이크로컨트롤러(MCU)를 이용한 과전류 정밀제어 방식 등이 사용되어 오고 있다. 하지만 이러한 방식들은 보호회로가 과전류가 흐르는 전선에 병렬접속 함으로써 2차 화재의 위험이 있을 수 있으며 입력전압의 비선형 왜곡에 취약한 단점을 가지고 있다. 또한 기존의 방식들은 제품의 단가가 비교적 크게 올라가므로 충분한 시장성을 확보하기가 쉽지 않다. 본 논문에서는 이러한 문제를 해결하고자 과전류가 흐르는 전선에 비접촉식 관통형 변류기를 설계하고 변류기의 2차 유도전류를 이용하여 과전류를 감지하여 사용자가 과전류 상황을 인지할 수 있도록 LED 및 부저 회로를 통하여 시각 및 청각적 신호를 전달하는 기능을 구현한다. 실험 결과들로부터 제안된 회로는 매우 경제적이고 간단하면서도 안정적으로 동작함을 확인 할 수 있다.

• 정보통신설비학회논문지
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• 제1권1호
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• pp.26-39
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• 2002

This paper describes design and implementation of home network control protocol for networked home appliances. The proposed network protocol has four-layered protocol structure and device-modem interface structure for the flexibility of modems based on power line communication. The standard message set is specified to guarantee the interoperability between various home appliances The proposed protocol can be easily implemented because it has minimum network overhead.

• 한국전기전자재료학회논문지
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• 제27권5호
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• pp.322-327
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• 2014

Internal corrosion of the distribution line can be detected in order to develop techniques of non-destructive inspection methods that operate only on the metal track eddy current diagnosis is possible by applying the technique investigated. Sensor for the production of a finite element method modeled by using an eddy current sensor, a distribution line by using an accelerated aging samples of sodium hydroxide was prepared. Sheathed cables for internal corrosion studies detected using an eddy current sensor is considered to be possible.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.848-851
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• 2005

This paper proposes a design of IIR notch filter with modified pole placements. The pole angle is derived from quadratic programming to find the appropriate pole position on the unit circle in z-plane in order to achieve the symmetry of the amplitude response. The simulation results are shown when compared with the conventional design technique. Moreover, it uses the TMS320C31 DSP chip for hardware implementation. Finally, the hardware implementation can be applied to removal of ECG baseline wander and elimination of AC power line interference in ECG signal.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1581-1585
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• 2005

This paper describes the design and implementation of a XCP (Xeline Control Protocol) network system. XCP is an information oriented protocol which delivers information with high reliability according to the predefined rule. The XCP network system is implemented with partly hardware and partly software based on the power line communication(PLC) environment. A network management tool which interacts with devices is also developed. In order to verify the feasibility of the proposed architecture, the implemented XCP network system is evaluated using a lighting control system.