• 제목/요약/키워드: Information cascade

검색결과 269건 처리시간 0.031초

나노구조 덴드리머의 광변위특성 (Photo Displacement Properties of Nano structure Organic Ultra Thin Films)

  • 송진원;최영일;조수영;김덕태;이우기;이경섭
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2004년도 추계학술대회 논문집
    • /
    • pp.23-26
    • /
    • 2004
  • Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understand. Photoisomerization in monolayers of a novel azobenzene compound, azobenzene dendrimer, was investigated for the first time by means of the absorption spectrum and Maxwell displacement current(MDC) technique. Dendrimers are well-defined macromolecules exhibiting a tree-like structure, first derived by the cascade molecule approach According to the absorption spectrum, trans-to-cis conversion ratio was estimated to the third generation of azobenzene dendrimer deposited onto a glass substrate. Temperature-dependent induced charge with trans-cis isomerization was also measured by means of MDC technique.

  • PDF

자기환경화를 가능하게 하는 자연교육 프로그램 - 미국의 미시건 4-H 어린이 정원, 바인더 파크 동물원 및 국립공원 사례를 중심으로 (Natural Education Programs for Personalization of Environment : - Cases of Michigan 4-H Children's Garden, Binder Park Zoo, and Natural Education Programs of National Parks in the United States)

  • 이선경;김상윤;윤여창
    • 한국환경교육학회지:환경교육
    • /
    • 제11권2호
    • /
    • pp.102-117
    • /
    • 1998
  • Responsible environmental behavior of Youths who will live in the 21C needs the ‘Personalization of Environment’, which means the process or the result of awareness to the non-personal environment as the personal environment to show the responsible environmental behaviors through the intended physical and psychological contacts to environment. This study intended to analyze various programs of national parks, zoo, children's garden and Project Learning Tree in the United States and to discuss the possibility of ‘personalization of environment’ and implication for environmental education of Korea. Literature review, field trips, personal interviews and internet searches were used to collect information and data. Programs of North Cascade National Park, Mt. Rainier National Park and 4-H Children's Garden in Michigan State University showed the cases of direct personalization of environment focusing on the direct contact with nature. The programs of Binder Park Zoo in Battle Creek and Project Learning Tree showed the possibilities of indirect personalization of environment forming meaningful relationships with nature through various indirect activities. It is suggested that various natural education programs in Unites States make nature and places meaningful for the people and it needs to be applied for the environmental education programs in Korea.

  • PDF

DS-CDMA/DPSK 셀룰라 이동통신 시스템에서 간섭 제거기와 RAKE 수신기에 의한 성능 개선 (Performance improvement of the DS-CDMA/DPSK cellular mobile communication system with CCI canceller and RAKE receiver)

  • 이경준;오창헌;조성준;채수환
    • 전자공학회논문지A
    • /
    • 제33A권4호
    • /
    • pp.37-46
    • /
    • 1996
  • In this paper, we analyzed the performance improvement of the DS-CDMA/dPSK cellular mobile communication system with CCI canceller and RAKE receiver techniques in mobile radio channel which is characterized by AWGN, Multi-user interference (mUI) and frequency-selective rayleigh fading. System capacity i.e., number of user per cell has been derived and the evaluated results are shown in figuraes as a function of PN code sequence length, number of RAKE receiver tap, BER and E$_{b}$/N$_{o}$. The voice activity factor is assumed to be 3/8 the number of sectors in a cell 3 and MUI is modeled as gaussian process. From the results, the capacity of the DS-CDMA/DPSK cellular mobile communication system is improved by adopting CCI canceller. When we adopt the RAKE receiver to mitigate the multipath fading, the error performance is improved and the amount of improvement is proportional ot the number of taps L in the case that each tap contains a signal component and the better of improvement can be obtained, the smaller of the SNR difference in each tap. The system capacity is more increased when the CCI canceller and the RAKE receiver is used in cascade.

  • PDF

소 모듈러스들로 구성된 RNS를 사용한 디지털 필터의 실현 (An Implementation of Digital Filters Usign the Residue Number System of small Modulus)

  • 이정문;배정이;최계근
    • 대한전자공학회논문지
    • /
    • 제20권6호
    • /
    • pp.6-10
    • /
    • 1983
  • 본 논문에서는 레지듀 연산(residue arithmetic)을 사용하여 디지탈 필터를 실현하는 한 가지 방법을 제시 하였다. 기존의 레지듀 디지탈 필터가 비교적 적은 비트 수를 갖는 신호만을 처리할 수 있었던 것에 비해, 여기서는 비트 슬라이스 알고리즘[1]의 원리를 적용함으로써 보다 많은 비트 수를 갖는 신호를 처리할 수 있도록 했으며, 또한 레지듀 가감산 및 승산은 연산표에 의해서 고속으로 수행될 수 있으므로 이를 이용하여 비트 슬라이스 알고리즘의 단점인 융통성 (flexibility)의 문제를 해결하였다. 실제로 종속 접속형 4차 버터워즈 저역통과 디지탈 필터를 구성하여 실험함으로써 이와 같은 사실들을 입증할 수 있었다.

  • PDF

A 256-Radix Crossbar Switch Using Mux-Matrix-Mux Folded-Clos Topology

  • Lee, Sung-Joon;Kim, Jaeha
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제14권6호
    • /
    • pp.760-767
    • /
    • 2014
  • This paper describes a high-radix crossbar switch design with low latency and power dissipation for Network-on-Chip (NoC) applications. The reduction in latency and power is achieved by employing a folded-clos topology, implementing the switch organized as three stages of low-radix switches connected in cascade. In addition, to facilitate the uniform placement of wires among the sub-switch stages, this paper proposes a Mux-Matrix-Mux structure, which implements the first and third switch stages as multiplexer-based crossbars and the second stage as a matrix-type crossbar. The proposed 256-radix, 8-bit crossbar switch designed in a 65nm CMOS has the simulated power dissipation of 1.92-W and worst-case propagation delay of 0.991-ns while operating at 1.2-V supply and 500-MHz frequency. Compared with the state-of-the-art designs in literature, the proposed crossbar switch achieves the best energy-delay-area efficiency of $0.73-fJ/cycle{\cdot}ns{\cdot}{\lambda}^2$.

Full Flash 8-Bit CMOS A/D 변환기 설계 (A Design of Full Flash 8-Bit CMOS A/D Converter)

  • 최영규;이천희
    • 대한전자공학회논문지
    • /
    • 제27권11호
    • /
    • pp.126-134
    • /
    • 1990
  • CMOS VLSI 기술에서 고속으로 데이타를 인식하기 위해서는 비교적 낮은 전달 콘덕턴스와 MOS 소자 장치들의 불균형을 극복하는 것이 중요하다. 그러나 CMOS 소자들의 한계 때문에 VLSI 회로설계는 일반적으로 CMOS 동작에 알맞도록 바이폴라 A/D(analog-to-digital)변환기가 사용되었다. 또한 파이프라인으로 종속 연결된 RSA에 의하여 전압 비교가 이뤄지는 VLSI CMOS 비교기를 설계하였다. 따라서 본 논문에서는 파이프라인으로 연결된 CMOS 비교기와 병합한 A/D 변환기를 설계하였다.

  • PDF

완료 트랜잭션 우선의 이동 실시간 트랜잭션 동시성 제어 기법 (A Concurrency Control Method of Mobile Real-time Transactions Using Committed Transaction Precedence)

  • 김경배;조숙경;배해영
    • 정보처리학회논문지D
    • /
    • 제11D권6호
    • /
    • pp.1213-1220
    • /
    • 2004
  • 이동 컴퓨팅 기술이 발전함에 따라 실시간으로 트랜잭션을 처리해야 하는 다양한 이동 애플리케이션에 대한 요구가 증가되고 있다. 원격 데이터에 대한 접근을 해야 하는 이동 환경에서 데이터에 대한 접근지연은 실시간 트랜잭션의 시간적인 제약조건 준수에 대한 가장 심각한 문제가 된다. 이동 실시간 트랜잭션은 트랜잭션의 결과의 정확성뿐만 아니라 트랜잭션의 완료 시간을 보장해야 한다. 본 논문에서는 이동 실시간 트랜잭션들 간의 충돌을 해결하기 위한 낙관적인 동시성제어 기법을 제안한다. 제한된 기법은 이동 환경에서의 핸드오버나 단절에 의해 발생되는 트랜잭션의 연속적인 철회와 지연의 영향을 최소화하였다.

나노구조 유기초박막의 광변위특성 (Photo Displacement Properties of Nano structure Organic Ultra Thin Films)

  • 송진원;최영일;조수영;김영근;이경섭
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
    • /
    • pp.468-471
    • /
    • 2004
  • Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems premising many technical applications. Until now, many methodologies have been developed in order to gain a better understand. Photoisomerization in monolayers of a novel azobenzene compound, azobenzene dendrimer, was investigated for the first time by means of the absorption spectrum and Maxwell displacement current (MDC) technique. Dendrimers are well-defined macromolecules exhibiting a tree-like structure, first derived by the cascade molecule approach. According to the absorption spectrum, trans-to-cis conversion ratio was estimated to the third generation of azobenzene dendrimer deposited onto a glass substrate. Temperature-dependent induced charge with trans-cis isomerization was also measured by means of MDC technique.

  • PDF

위암에서 순환종양세포의 임상적 의의 (Clinical Significance of Circulating Tumor Cells in Gastric Cancer)

  • 전혜경;김광하
    • 대한상부위장관⦁헬리코박터학회지
    • /
    • 제18권3호
    • /
    • pp.162-167
    • /
    • 2018
  • Cancer specimens obtained via surgical resection or biopsy are generally used to understand tumor-associated alterations; however, those approaches cannot always be performed because of their invasive nature, and they may fail to reflect current tumor dynamics and drug sensitivity, which may change during the therapeutic process. Therefore, many research groups have focused on developing a non-invasive biomarker with the ability to monitor tumor dynamics. Circulating tumor cells (CTCs) are metastatic cells released from the primary tumor into the bloodstream. Hematogenous spreading of CTCs is a crucial step in the metastatic cascade, which leads to the formation of overt metastases. CTCs have attracted considerable attention because of their easy accessibility and their superiority over conventional tumor markers. Detecting CTCs is considered a valuable modality to determine prognosis and monitor response to systemic therapies in patients with gastric cancer. Moreover, molecular analyses of CTCs may provide important biological information for individual patients with cancer, which may lead to the development of personalized cancer treatment. In this article, we review potential roles and clinical applications of CTCs in patients with gastric cancer.

모델 파라미터 없는 쿠프만 연산자 기반의 영구자석 동기전동기의 속도제어 (Model Parameter-free Velocity Control of Permanent Magnet Synchronous Motor based on Koopman Operator)

  • 김준식;우희진;최영진
    • 로봇학회논문지
    • /
    • 제17권3호
    • /
    • pp.308-313
    • /
    • 2022
  • This paper proposes a velocity control method for a permanent magnet synchronous motor (PMSM) based on the Koopman operator that does not require model parameter information except for pole-pair of the motor and external load. First, the Koopman operator is derived using observable functions and observation data. Then, the desired q-axis current corresponding to the desired velocity is generated using the relationship between the continuous-time Koopman operator and the dynamics of PMSM. Also, the dynamic equation of PMSM is expressed as a linear form in observable space using the discrete-time Koopman operator. Finally, it is applied to the linear quadratic regulator (LQR) to derive the final form of control input. To verify the proposed method, the conventional cascade PI controller and the LQR controller configured with the existing technique are compared with the proposed method in the viewpoint of q-axis current generation and velocity tracking performance in an environment with noise and external load.