• 제목/요약/키워드: multi-modem

검색결과 121건 처리시간 0.026초

정진폭 다중 부호 이진 직교 변복조기의 FPGA 설계 및 SoC 구현 (FPGA Design and SoC Implementation of Constant-Amplitude Multicode Bi-Orthogonal Modulation)

  • 홍대기;김용성;김선희;조진웅;강성진
    • 한국통신학회논문지
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    • 제32권11C호
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    • pp.1102-1110
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    • 2007
  • 본 논문에서는 기존의 정진폭 다중 부호 이진 직교 (CAMB: Constant-Amplitude Multi-code Biorthogonal) 변조 이론을 적용한 변복조기를 프로그래밍 가능한 게이트 배열 (FPGA: Field-Programmable Gate Array)을 사용하여 설계하고 시스템 온 칩 (SoC: System on Chip)으로 구현하였다. 이 변복조기는 FPGA을 이용하여 타겟팅 한 후 보드실험을 통해 설계에 대한 충분한 검증을 거쳐 주문형 반도체 (ASIC: Application Specific Integrated Circuit) 칩으로 제작되었다. 이러한 12Mbps급 모뎀의 SoC를 위하여 ARM (Advanced RISC Machine)7TDMI를 사용하였으며 64K바이트 정적 램 (SRAM: Static Random Access Memory)을 내장하였다. 16-비트 PCMCIA (Personal Computer Memory Card International Association), USB (Universal Serial Bus) 1.1, 16C550 Compatible UART (Universal Asynchronous Receiver/Transmitter) 등 다양한 통신 인터페이스를 지원할 뿐 아니라 ADC (Analog to Digital Converter)/DAC (Digital to Analog Converter)를 포함하고 있어 실제 현장에서 쉽게 활용될 수 있을 것으로 기대된다.

패션컬렉션에 나타난 맥시멀리즘 패션 표현유형 분석 (Characteristic to Express Maximalism Fashion Appearing in Fashion Collection)

  • 정선화;정현주
    • 한국의상디자인학회지
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    • 제11권1호
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    • pp.155-167
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    • 2009
  • This study reviewed the basic principle of "Maximalism" fashion and analyzed the properties of fashion types with found the frequencies of various styles and design factors of "Maximalism" fashion in collection. The limits of this study is from 2001, s/s, maximalism was embossed in a modem fashion, to 2007, f/w, and collected the fashion collection pictures from www.samsungdesign.net and www.style.com. The results of this study are as follows. First, the most frequent style of "Maximalism" design showed in International fashion collection was "exaggerated style." Second, the design factors of "Maximalism" fashion were also examined. In case of silhouette, "hourglass silhouette" was the most frequent silhouette. In case of pattern, "solid" color was the most frequently used. In case of materials, the soft materials were the most frequently used. Third, the frequencies of design factors of maximalism by presentation types was compared and analyzed. In case of expansion, "bulk silhouette" was the most frequent silhouette to be appeared, and about multi-ethnic, futurelism, and elegance, "hourglass silhouette" was frequent appeared. In case of pattern, "solid" color was the most frequently used in all types. In case of materials, the hard materials were the most frequently used in expansion, multi-ethnic and futurelism. "Maximalism" fashion which is most splendid trend would grow up rapidly in the modem fashion market and influence on the other fashion trend in our every day life. Consequently, this research can be referred as practical information in fashion marketing and it will contribute to the future fashion research as well.

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Performance Enhancement of Multi-Band OFDM using Spectrum Equalizer

  • Yoon, Sang-Hun;Jung, Jun-Mo
    • Journal of information and communication convergence engineering
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    • 제8권6호
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    • pp.687-689
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    • 2010
  • In this paper, the equalization for frequency slope of path loss in Multi-Band(MB) OFDM UWB is proposed. The path loss of a signal is proportionate to the square of the signal's frequency. So, the received signal amplitudes of OFDM subcarrier can be different up to 3dB when MB-OFDM occupies bandwidth over 1.5GHz. The differences of subcarrier-amplitudes make an effective of 0.3 bit reduction of soft decision bits of viterbi decoder, and when the effective of 0.3 bit reduction can cause 0.5dB SNR degradation. This paper proposes two modem architectures which compensate for the degraded subcarrier by multiplying the reciprocal of degraded values in analog or digital domain. It is shown that, for the proposed architecture applied to MB-OFDM UWB, the performance improvements up to 0.5dB can be obtained over the conventional uncompensated receiver architecture.

다단 왕복동 공기압축기의 평형추 설계 (Counter Weight Design of Multi-stage Reciprocating Air Compressors)

  • 김영철;김병옥;신현익
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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    • pp.656-661
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    • 2003
  • Modem reciprocating air compressors have tendency to a multi-stage W-type or V-type cylinder arrangement for the purpose of high outlet pressure, compactness and low vibration and noise. A valid counter weight calculation method using the complex expression is proposed for reducing the inertia forces of the compressor. Counter weight removes only 1st forward whirl component. Counter weight formulations are applied to the six various compressor structures which are (a) 1 cylinder single-throw crank shaft, (b) 2 cylinder single-throw crank shaft (c) 2 cylinder double-throw clank shaft, (d) 3 cylinder single-throw crank shaft, (e) 4 cylinder single-throw crank shaft and (f) 4 cylinder double-throw crank shaft. The improvement of performance is verified through available vibration test.

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Development of Acoustic Target Strength Analysis System for Submarine

  • Kwon, Hyun-Wung;Hong, Suk-Yoon;Jeon, Jae-Jin;Song, Jee-Hun
    • International Journal of Ocean System Engineering
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    • 제3권3호
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    • pp.158-163
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    • 2013
  • The acoustic target strength (TS) is one of the most important parameters for a submarine's stealth design. Because modem submarines are larger than their predecessors, TS must be managed at each design stage in order to reduce it. To predict the TS of a submarine, TASTRAN R1 was developed based on a Kirchhoff approximation in a high-frequency range. This program can present TS values that include multi-bounce effect in the exterior and interior of the structure by combining geometric optics (GO) and physical optics (PO) methods, anechoic coating effect by using the reflection coefficient, and response time pattern for a detected target. In this paper, TS calculations for a submarine model with the above effects are simulated by using this developed program, and the TS results are discussed.

Multi SHA 구조의 파이프라인 아날로그-디지털 변환기 설계 (A Design of Pipelined Analog-to-Digital Converter with Multi SHA Structure)

  • 이승우;나유찬;신홍규
    • 한국통신학회논문지
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    • 제30권2A호
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    • pp.114-121
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    • 2005
  • 본 논문에서는 고속 동작을 위한 multi SHA(ammple and hold amplifier) 구조의 파이프라인 A/D 변환기 (analog-to-digital converter)를 제안하였다. 제안된 구조는 변환 속도를 높이기 위해, 동일한 SHA를 병렬로 연결하여 multi SHA를 구성하였다. 이를 비중첩 클럭(nonoverlapping clock)에서 동작하도록 하여 셀을 구성하는 SHA의 수와 비례한 빠른 샘플링 속도를 얻을 수 있도록 하였다. 제안된 구조를 적용하여 VDSL(very high-speed digital subscriber line) 모뎀의 아날로그 front-end단의 요구 사항을 만족하는 파이프라인 A/D 변환기를 설계하였다. 설계된 A/D 변환기의 DNL(differential nonlinearity)과 INL(integral nonlinearity)은 각각 $0.52LSB{\sim}-0.50LSB,\;0.80LSB{\sim}-0.76LSB$의 특성을 나타내어 설계 사양을 만족함을 확인하였다. 또한 2048 point에 대한 FFT를 수행한 결과 SNR이 약 66dB로 10.7 비트의 해상도가 얻어짐을 확인하였으며, 전력 소모는 24.32mW로 측정되었다.

${\cdot}$현대 민촌의 사회공간적 성격과 영역성 - 부여군 장암면 장하리의 사례 - (A Study on the Territoriality and the Socio-spatial Characteristics of a Commoner's Settlement in Modern Times)

  • 전종한
    • 대한지리학회지
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    • 제40권6호
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    • pp.613-630
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    • 2005
  • 이 논문은 근${\cdot}$현대 민촌의 사회공간적 성격과 영역성에 접근하는 일환으로 촌락민의 제 관계에 대한 검토와 더불어 촌락권의 중층성 문제를 탐구한 것이다. 연구 지역인 부여군 장암면 장하리는 금강 범람원 변에 입지한 민촌적 배경의 진주강씨 종족마을이다. 이 촌락은 마을이 형성된 17세기 이후 지금까지 견고한 사회적 집단성을 바탕으로 20세기 중후반의 이른바 촌락 해체기를 경험하지 않은 것이 특징이다. 특히 근 현대시기를 지나면서 이 마을에는 촌락민들을 둘러싼 제 관계를 반영하며 촌락 영역의 다양한 경계들, 즉 중층적 촌락권이 만들어져 왔다. 필자는 촌락민을 둘러싼 제 관계를 인간-자연관계, 사회적 관계, 정치적 관계라는 세가지 차원으로 나누어서 각각에 상응하는 촌락권의 범위와 내용을 검토하였다. 장하리와 검신들을 묶는 인간-자연 관계의 촌락권을 확인할 수 있었고, 장하리와 북고리를 연결하는 통혼권에 기초한 사회적 관계의 촌락권이 19세기 이후 여전히 존속하고 있다는 점, 그리고 최근에는 장하리, 북고리, 상황리, 하황리로 연결되는 정치적 연대의 촌락권이 출현하였음을 포착할 수 있었다. 과거의 신분 관계에 기초한 통혼권의 경우처럼 특정 촌락권이 소멸하기도 하지만 근 현대 이후 사회 경제적 환경의 변화에 따라서 새로운 유형의 촌락권이 탄생하는 경우도 있음을 볼 수 있었다. 요컨대 중층적 촌락권으로 대변되는 이 마을의 영역성은 장하리 주민들이 처했던 환경적 특수성을 표현하고 사회${\cdot}$문화적 차별성을 표상하며 정치적 연대성을 함축하는 것으로 해석되었다.

멀티 홉 무선 센서 네트워크를 위한 부호화된 FSK 시스템의 성능 해석 (Performance Analysis of Coded FSK System for Multi-hop Wireless Sensor Networks)

  • 오규태;노재성
    • 한국항행학회논문지
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    • 제11권4호
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    • pp.408-414
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    • 2007
  • 마이크로 센서 소자와 무선 네트워크 기술의 발전으로 인하여 에너지 효율적이고 저가격의 무선 센서 노드의 개발이 가능하게 되었다. 본 논문에서는 낮은 전력 소모와 우수한 BER(Bit Error Rate) 성능을 위해 FEC 기술을 적용한 FSK 모뎀 기반의 멀티 홉 무선 센서 네트워크를 제안한다. FEC 기술은 부호화 및 복호화를 위한 추가의 전력을 필요로 하며 센서 노드안에 구현하기 위한 복잡한 기능을 필요로 한다. 성능 평가를 위하여 본 논문에서는 채널 파라미터, 홉의 수, 전송 비트의 수, 노드사이의 거리를 함수로 하여 수신된 비트 및 부호어의 확률을 계산하였다.

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전압 변동률을 고려한 수도권 전압 안정화 다단계 부하차단 적용 방안 (Multi-level UnderVoltage Load Shedding Scheme Considering Rate of Change of Voltage for Voltage Stability)

  • 이윤환;김태균;김지훈;이병준;강부일;조종만
    • 전기학회논문지
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    • 제58권12호
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    • pp.2335-2341
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    • 2009
  • High technique growth of modem times and high industrial facility in consequence of buildings demand for electric power of an extensive scale with stability supply and maintenance of high quality. But, power system always have risk of network contingency. When power system break out disturbance, it circumstantially happen like uncontrolled loss of load developing from of cascading. Severely which would be raised wide area blackout, plan to prevent, which make stability through a little of load shedding and multi-level UnderVoltageLoadShdding should work. This paper presents target, sensitivity of bus voltage have choose appropriating load shedding location and load shedding decision making logic with considering rate of change of voltage have studied multi-level under voltage load shedding scheme. Calculation of rate of change of voltage applied method of least square. As a result, we are studied an dynamic analysis of 2008 summer peak data. We have been known that network analysis is a little development and developing UnderVoltageLoadShedding scheme.

1980년대 이후 한국 주거문화에 나타난 근대화의 재평가 (Revaluation of the Modernization in the Korean Housing Culture Since 1980s′)

  • 은난순
    • 가정과삶의질연구
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    • 제22권5호
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    • pp.59-73
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    • 2004
  • Since 1980s' Korea had a great change on the housing culture by the supply of multi-family housing stock both on the macro-social and micro-social aspects. The purpose of this study was to examine the changes and the characteristics of housing environments which were estimated its modernization, and to examine the personal life under the change of housing environments. So I would like to revaluation the characteristics of modernization between the 1980s' and 1990s'. Therefore references were made to various papers, reports, the statistical data, newspaper reports, advertisements and magazines during that period. As a result, this paper came to the remarks as follows: 1. The success of modernization on the housing environments since 1980s' was the Quantitative growth of housing supply by multi-family housing. In spite of this, the Quantitative growth of housing supply and the improvement in Quality like housing space per person had the characters which was 'out of valence on the division'. 2. The Qualitative improvement of modem housing life by the development of housing industries could be said the improvement owing to develop of facilities and equipments. The introduction of up-to-date facilities and equipments realized the convenience and the rationality of living in the house. Although the improvement on the physical things deteriorated the modernized spaces to uniform things by commercial strategies. 3. The life in the multi-family housing which gives protection to personal privacy was settle down on the extremely individualized life without common things within the neighbors. Multi-family housing which was a production of process of modernization came true the growth in an appearance and the variety in the inside, but for the aspect of residents' everyday life in the multi-family housing, the Korean traditional relationship was collapsed and a sense of incompatibility within the residents was created.