• 제목/요약/키워드: Side Channel

검색결과 926건 처리시간 0.027초

30피트급 고속 알루미늄 레저보트 선형개발과 저항성능에 관한 연구 (Study on Hull Form Development and Resistance Performance of High Speed Aluminum Leisure Boat)

  • 정우철;김도정;최홍식
    • 한국해양공학회지
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    • 제26권6호
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    • pp.14-18
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    • 2012
  • A 30ft class aluminum leisure boat is newly developed and the resistance performances are investigated by a model test at a high-speed circulating water channel. The effect of a fin attached to the side of the hull is studied at two different displacements. Wave patterns are observed to make clear the relationship between the resistance performance and wave characteristics. It can be found that a chine position at the draft line can have a strong effect on the resistance performance around a certain velocity range.

An Analysis of the throughput performance of some continuous A.R.Q, Schemes

  • Jung, Doo-Young;Kim, Sung-Chun
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -1
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    • pp.73-76
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    • 2000
  • In the basic continuous ARQ schemes (Go-Back-N or Selective Repeat ARQ), each block is continuously transmitted without interruptions. Only when the transmitter receives NAK from the receiver side, the transmitter stops sending current data block and retransmit the erroneous block (Naked block). When channel error rate increases and become sufficiently high, there exists a point at which each block of message is transmitted, on average, more than once. Under such conditions, it will be more efficient to send continuously two or more copies(generally $\ell$ copies) of each block from the first transmission over noisy channel. A request for repeat will be made again only when none of $\ell$ duplicates are received correctly. By this way, the proposed scheme yields a better throughput efficiency and holds nearly constant throughput as compared to others continuous A.R.Q schemes under wide error rate variations (0 < P < 0.3).

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TWO-Ray 라이시안 채널에서 차량간 통신 시스템에서의 성능분석 (Performance Analysis of Inter-Vehicle Communication System in Two-Ray Rician Channel)

  • 김춘구;이정도;강희조
    • 한국정보통신학회논문지
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    • 제5권2호
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    • pp.263-268
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    • 2001
  • 본 논문은 근거리에서의 차량간 통신에 밀리미터나 광전파를 분석하는데 효과적인 Ray Tracing방법을 도입하여 오율특성을 분석하였다. 분석환경으로는 간섭신호에 강한 장점을 지니며 산소흡수에 의한 감쇠가 크며 주파수 재사용효율이 좋은 60㎓ 대역에서의 비트오율을 분석하였다. 전파모델로 지면반사파, 콘크리트벽에 의한 반사와 옆 도로를 달리는 차량에 의한 반사를 고려한 Two-Ray 라이시안 채널에서의 다중접속자에 의한 DS/CDMA 시스템의 비트오율특성을 분석하여 검토하였다. 성능 개선 기법으로는 MRC 다이버시티를 채용하였다.

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Acyclic Vanilloid Receptor Antagonist Based on Capsazepine

  • Park, Hyeung-Geun;Park, Mi-Kyoung;Choi, Ji-Yeon;Choi, Se-Hoon;Lee, Ji-Hye;Suh, Young-Ger;Oh, Uh-Taek;Kim, Hee-Doo;Lee, Jee-Woo;Park, Young-Ho;Jeong, Yeon-Su;Choi, Jin-Kyu;Jew, Sang-Sup
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.349.1-349.1
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    • 2002
  • Capsaicin. the pungent component of chili pepper. opens a novel cation selective ion channel in the plasma membrane of peripheral sensory neurons. Capsaicin channel agonists induce pain upon topical application in the early stage. which is followed by a period of desensitization. Although the agonists have been studied as a analgesics, their initial irritancy became sever side effect. So competive antagonists have been pursued as a novel pharmacological agent for analgesics, rather than agonists. (omitted)

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벽에서 열원이 있는 수직채널안의 자연대류열전달 (Free Convective Heat Transfer in a Vertical Channel with Heat Source at the Wall)

  • 박희용;두민수
    • 대한설비공학회지:설비저널
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    • 제14권2호
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    • pp.108-117
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    • 1985
  • In this study, a numerical analysis was performed for the natural convection heat transfer in a vertical channel which was consisted of two finite-thickness vertical walls with heat source. The ratio of the thermal conductivity of wall to air played an important role in the analysis. The case for which one side wall has protrusion resistances was also examined. The governing equations for the system was discretized by control volume formulation and solved by SIMPLE method. As the result of this study, it was found that the uniform heat flux boundary condition could be applied when the conductivity ratio was below approximately 50 and the uniform temperature boundary condition could be used when the conductivity rat io was over approximately 15,000. However, when the conductivity ratio was between 50 and 15,000, the thermal conductivity ratio value should be considered for the analysis. It was also found that the existence of protrusion resistance influenced the thermal field up to the distance of 3-4 times of the protrusion length.

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효과적인 딥러닝 기반 비프로파일링 부채널 분석 모델 설계방안 (Design of an Effective Deep Learning-Based Non-Profiling Side-Channel Analysis Model)

  • 한재승;심보연;임한섭;김주환;한동국
    • 정보보호학회논문지
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    • 제30권6호
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    • pp.1291-1300
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    • 2020
  • 최근 딥러닝 기반 비프로파일링 부채널 분석이 제안됐다. 딥러닝 기반 비프로파일링 분석은 신경망 모델을 모든 추측키에 대해 학습시킨 뒤, 학습된 정도의 차이를 통해 올바른 비밀키를 찾아내는 기법이다. 이때, 신경망 학습모델 설계에 따라 비프로파일링 분석성능이 크게 달라지기 때문에 올바른 모델 설계의 기준이 필요하다. 본 논문은 학습모델 설계에 사용 가능한 2가지 loss 함수와 8가지 label 기법을 설명하고, 비프로파일링 분석과 소비전력모델 관점에서 각 label 기법의 분석성능을 예측했다. 해밍웨이트 소비전력모델을 가정했을 때의 비프로파일링 분석 특징을 고려해서 One-hot 인코딩을 적용하지 않은 HW(Hamming Weight) label과 CO(Correlation Optimization) loss를 적용한 학습모델이 가장 좋은 분석성능을 가질 것으로 예측했다. 그리고 AES-128 1라운드 Subbytes 연산 부분 데이터 집합 3가지에 대해 실제 분석을 수행했다. 제시한 각 label 기법과 loss 함수를 적용한 총 16가지 MLP(Multi-Layer Perceptron)기반 학습모델로 두 데이터 집합을 비프로파일링 분석하여 예측에 대해 검증했다.

A STANDARD METHOD FOR JOINTING CAMEL CARCASSES WITH REFERENCE TO THE EFFECT OF SLAUGHTER AGE ON CARCASS CHARACTERISTICS IN NAJDI CAMELS. 3. PARTITION AND DISTRIBUTION OF CARCASS FAT

  • Abouheif, M.A.;Basmaeil, S.M.;Bakkar, M.N.
    • Asian-Australasian Journal of Animal Sciences
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    • 제4권3호
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    • pp.219-225
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    • 1991
  • The influence of age on the relative growth patterns of subcutaneous, intermuscular, intramuscular, perirenal, channel and hump fat in relation to the total fat weight in carcass sides of 18 Najdi male camels averaging 8, 16 and 26 months of age has been investigated. The total fat weight in a carcass side increased (p<.01) from 17.3% to 27.1% as the camel age increased from 8 to 26 months. However, at all ages studied, intermuscular fat weight was the largest fat depot, followed, in order, by subcutaneous and intramuscular fat. The change in weight of the intramuscular, intermuscular and subcutaneous fat between 8 and 26 months of age was greater, reaching 6.7, 4.3 and 4 times respectively, than the hump, channel and perirenal fat weight which increased by 3.6, 2.5 and 2.3 times, respectively. The allometric growth coefficient (${\beta}$) for intramuscular fat in relation to the total carcass fat weight was the highest, followed, in order, by intermuscular, subcutaneous, hump, channel and perirenal fat.

Optimization of Double Gate Vertical Channel Tunneling Field Effect Transistor (DVTFET) with Dielectric Sidewall

  • WANG, XIANGYU;Cho, Wonhee;Baac, Hyoung Won;Seo, Dongsun;Cho, Il Hwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제17권2호
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    • pp.192-198
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    • 2017
  • In this paper, we propose a novel double gate vertical channel tunneling field effect transistor (DVTFET) with a dielectric sidewall and optimization characteristics. The dielectric sidewall is applied to the gate region to reduced ambipolar voltage ($V_{amb}$) and double gate structure is applied to improve on-current ($I_{ON}$) and subthreshold swing (SS). We discussed the fin width ($W_S$), body doping concentration, sidewall width ($W_{side}$), drain and gate underlap distance ($X_d$), source doping distance ($X_S$) and pocket doping length ($X_P$) of DVTFET. Each of device performance is investigated with various device parameter variations. To maximize device performance, we apply the optimum values obtained in the above discussion of a optimization simulation. The optimum results are steep SS of 32.6 mV/dec, high $I_{ON}$ of $1.2{\times}10^{-3}A/{\mu}m$ and low $V_{amb}$ of -2.0 V.

Characteristics of Heat Transfer in the Channel with Twisted Tape

  • Ahn, Soo-Whan;Kang, Ho-Keun
    • International Journal of Air-Conditioning and Refrigeration
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    • 제15권3호
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    • pp.122-128
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    • 2007
  • Heat transfer distributions and friction factors in square channels (3.0 ${\times}$ 3.0 cm) with twisted tape inserts and with twisted tape inserts plus interrupted ribs are respectively investigated. The rib height-to-channel hydraulic diameter ratio, $e/D_h$, is kept at 0.067 and test section length-to-hydraulic diameter ratio, $L/D_h$ is 30. The square ribs are arranged to follow the trace of the twisted tape and along the flow direction defined as axial interrupted ribs. The twisted tape is 0.1 mm thick carbon steel sheet with diameter of 2.8 cm, length of 90 cm, and 2.5 turns. Two heating conditions are investigated for test channels with twisted tape inserts and rib turbulators: (1) electric heat uniformly applied to four side walls of the square duct, and (2) electric heat uniformly applied to two opposite ribbed walls of the square channel. Results show that the twisted tape with interrupted ribs provides a higher overall heat transfer performance over the twisted tape with no ribs.

A Numerical Study on Heat Transfer and Friction in Rectangular Channel with Inclined Perforated Baffles

  • Putra, Ary Bachtiar Krishna;Ahn, Soo-Whan;Kang, Ho-Keun
    • Journal of Advanced Marine Engineering and Technology
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    • 제32권7호
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    • pp.1003-1012
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    • 2008
  • A three dimensional numerical study has been applied to predict the turbulent fluid flow and heat transfer characteristics for the rectangular channel with different types of baffles. Four different types of the baffles are used. The inclined baffles have the width of 19.8 cm, the square diamond type hole having one side length of 2.55 cm, and the inclination angle of $5^{\circ}$. Reynolds number is varied between 23,000 and 57,000. The SST k-${\omega}$ turbulence model is used in the present numerical study. The validity of the numerical results is examined with the experimental data. The numerical results of the flow field depict that the flow patterns around the different baffle type are entirely different and it significantly affects the local heat transfer characteristics. The heat transfer and friction factor depend significantly on the number of baffle holes. It is found that the heat transfer enhancement of baffle type II (3 hole baffle) has the best values.