• Title/Summary/Keyword: Side-channel

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Performance Prediction of Side Channel Type Fuel Pump (사이드채널형 연료펌프의 성능예측)

  • Choi, Young-Seok;Lee, Kyoung-Yong;Kang, Shin-Hyoung
    • The KSFM Journal of Fluid Machinery
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    • v.6 no.2 s.19
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    • pp.29-33
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    • 2003
  • The periphery pump (or regenerative pump) has been generally applied in the automotive fuel pump due to their low specific speed (high heads and small flow rate) with stable performance curves. In this study, the performance prediction of side channel type periphery pumps has been developed. The prediction of the circulatory flow rate is based on the consideration of the centrifugal force field in the side-channel and in the impeller vane grooves. For the determination of performance curve (head-flow rate), momentum exchange theory is used. The effects of various geometric parameters and loss coefficients used in the performance prediction method on the head and efficiency are discussed, and the results were compared with experimental data.

Performance Prediction of Side Channel Type Fuel Pump (사이드채널형 연료펌프의 성능예측)

  • Choi Y. S.;Lee K. Y.;Kang S. H.
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.581-584
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    • 2002
  • The periphery pump(or regenerative pump) has been generally applied in the automotive fuel pump due to their low specific speed(high heads and small flow rate) with stable performance curves. In this study, the performance prediction of side channel type periphery pumps has been developed. The prediction of the circulatory flow rate is based on the consideration of the centrifugal force field in the side-channel and in the impeller vane grooves. For the determination of performance curve(head-flow rate), momentum exchange theory is used. The effects of various geometric parameters and loss coefficients used in the performance prediction method on the head and efficiency are discussed and the results were compared with experimental data.

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3 Dimensional Flow Analysis of Small Regenerative Pump (소형 재생펌프의 3차원 성능 해석에 관한 연구)

  • Kang, Shin-Hyoung;Lim, Hyung-Soo;Ryu, Su-Hyun;Shim, Chang-Yeul
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.12
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    • pp.1600-1607
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    • 2004
  • Performance of a regenerative pump is evaluated based on the calculated through flows using the CFX-TASCflow code. Flow calculations are performed in one vane to vane space of the impeller and side channel. The flow is very complex three dimensional with a strong radial vortex due to centrifugal force and an axial vortex due to re-circulating flow between the impeller and the side channel. Momentum exchange on the plane between the impeller and the side channel are evaluated to estimate design parameters and viscous losses in the pump. The present study contributes to showing the capability of flow simulation of complex flow in the regenerative pump by comparing the calculated performance with the measured value.

Key-dependent side-channel cube attack on CRAFT

  • Pang, Kok-An;Abdul-Latip, Shekh Faisal
    • ETRI Journal
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    • v.43 no.2
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    • pp.344-356
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    • 2021
  • CRAFT is a tweakable block cipher introduced in 2019 that aims to provide strong protection against differential fault analysis. In this paper, we show that CRAFT is vulnerable to side-channel cube attacks. We apply side-channel cube attacks to CRAFT with the Hamming weight leakage assumption. We found that the first half of the secret key can be recovered from the Hamming weight leakage after the first round. Next, using the recovered key bits, we continue our attack to recover the second half of the secret key. We show that the set of equations that are solvable varies depending on the value of the key bits. Our result shows that 99.90% of the key space can be fully recovered within a practical time.

A Study on the Compensation of Communication Channel Using Predistorter (사전 왜곡기를 이용한 통신 채널의 보상에 관한 연구)

  • Lim, Seung-Gag
    • Journal of the Korean Institute of Telematics and Electronics T
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    • v.36T no.4
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    • pp.94-102
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    • 1999
  • This paper is related with the compensation of communication channel characteristics using predistorter, and the considered characteristic is the additive noise, phase rotation and frequency selective fading which occurred in communication channel. Predistorter can minimize the effect of obstacle element which occured in channel at receiving side by transmitting the predistortion of signal after modulation, the coefficient of inverse electrical charateristic of communication channel is performed at transmitting side. For this purpose, the predistorter is designed by using Tricepstrum Equalization Algorithm which is adaptive equlizer algorithm, and the receiving side must transmit the probing signal to transmitting side. Using the probing signal, the transmitting side can obtain the inverse characteristic coefficient of communication channel, and this probing signal must be transmitted periodically. We assumed that the channel characteristic do not change during this one period. As a result of computer simulation, we confirmed that the performance of predistorter was fairly good as same as the adaptive equalizer, and this technique have a effectiveness that can be used in the forward channel of mobile communication in order to achieve high speed transmission.

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Numerical Study of Channel Area Effects on the Performance Characteristics of Regenerative Type Fuel Pump (재생형 연료펌프의 채널 면적 변화가 성능 특성에 미치는 영향에 대한 수치해석적 연구)

  • Lee, Kyoung-Yong;Choi, Young-Seok;Son, Kwang-Eun
    • The KSFM Journal of Fluid Machinery
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    • v.10 no.5
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    • pp.41-45
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    • 2007
  • The effects of channel area on the performance of regenerative type fuel pump were numerically studied by commercial CFD code (ANSYS CFX-10). To examine the effects of channel area, the shapes of the side channel and blade were simplified. The channel area affected the flow characteristics of the internal recirculation flow between the side channel and the blade groove and also made a difference in the overall performance. These loss mechanism with circulation flow were adopted as a loss coefficient in the performance prediction program. The loss coefficient was newly derived from the results of calculations with different channel area, and compared with the experimental results in the reference paper and used to modify the performance prediction program. The circulation flow characteristics with different channel area, which is related with loss mechanism, were also discussed with the results of 3-dimensional flow calculations.

Theoretical analysis of simply supported channel girder bridges

  • Hu, Hong-Song;Nie, Jian-Guo;Wang, Yu-Hang
    • Structural Engineering and Mechanics
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    • v.56 no.2
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    • pp.241-256
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    • 2015
  • Channel girder bridges that consist of a deck slab and two side beams are good choices for railway bridges and urban rail transit bridges when the vertical clearance beneath the bridge is restricted. In this study, the behavior of simply supported channel girder bridges was theoretical studied based on the theory of elasticity. The accuracy of the theoretical solutions was verified by the finite element analysis. The global bending of the channel girder and the local bending of the deck slab are two contributors to the deformations and stresses of the channel girder. Because of the shear lag effect, the maximum deflection due to the global bending could be amplified by 1.0 to 1.2 times, and the effective width of the deck slab for determining the global bending stresses can be as small as 0.7 of the actual width depending on the width-to-span ratio of the channel girder. The maximum deflection and transversal stress due to the local bending are obtained at the girder ends. For the channel girders with open section side beams, the side beam twist has a negligible effect on the deflections and stresses of the channel girder. Simplified equations were also developed for calculating the maximum deformations and stresses.

Side Channel Attacks on HIGHT and Its Countermeasures (HIGHT에 대한 부채널 분석 및 대응 방법)

  • Kim, Tae-Jong;Won, Yoo-Seung;Park, Jin-Hak;An, Hyun-Jin;Han, Dong-Guk
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.25 no.2
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    • pp.457-465
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    • 2015
  • Internet of Things(IoT) technologies should be able to communication with various embedded platforms. We will need to select an appropriate cryptographic algorithm in various embedded environments because we should consider security elements in IoT communications. Therefore the lightweight block cryptographic algorithm is essential for secure communication between these kinds of embedded platforms. However, the lightweight block cryptographic algorithm has a vulnerability which can be leaked in side channel analysis. Thus we also have to consider side channel countermeasure. In this paper, we will propose the scenario of side channel analysis and confirm the vulnerability for HIGHT algorithm which is composed of ARX structure. Additionally, we will suggest countermeasure for HIGHT against side channel analysis. Finally, we will explain how much the effectiveness can be provided through comparison between countermeasure for AES and HIGHT.

Side-Channel Cryptanalysis on Stream Cipher HC-128 for Mobile Ad-Hoc Network Environments (이동 Ad-Hoc 네트워크 환경에 적합한 스트림 암호 HC-128의 부채널 안전성 분석)

  • Bae, KiSeok;Park, YoungHo;Moon, SangJae
    • Journal of Korea Society of Industrial Information Systems
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    • v.17 no.6
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    • pp.11-17
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    • 2012
  • The HC-128 stram cipher which selected for the final eSTREAM portfolio is suitable for mobile Ad-Hoc network environments because of the ability of high-speed encryption in restricted memory space. In this paper, we analyzed the vulnerability of side channel analysis attack on HC-128 stream cipher. At the first, we explain a flaw of previous theoretical analysis result which defined the complexity of side-channel attack of HC-128 stream cipher as 'low' and then re-evaluate the security against side-channel attack by estimating the concrete complexity for recovering the secret key. As a result, HC-128 stream cipher is relatively secure against side-channel attack since recovering the secret key have $2^{65}$ computation complexity which is higher than other stream cipher's one.

Side-Channel Attacks on Square Always Exponentiation Algorithm (Square Always 멱승 알고리듬에 대한 부채널 공격)

  • Jung, Seung-Gyo;Ha, Jae-Cheol
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.24 no.3
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    • pp.477-489
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    • 2014
  • Based on some flaws occurred for implementing a public key cryptosystem in the embedded security device, many side-channel attacks to extract the secret private key have been tried. In spite of the fact that the cryptographic exponentiation is basically composed of a sequence of multiplications and squarings, a new Square Always exponentiation algorithm was recently presented as a countermeasure against side-channel attacks based on trading multiplications for squarings. In this paper, we propose Known Power Collision Analysis and modified Doubling attacks to break the Right-to-Left Square Always exponentiation algorithm which is known resistant to the existing side-channel attacks. And we also present a Collision-based Combined Attack which is a combinational method of fault attack and power collision analysis. Furthermore, we verify that the Square Always algorithm is vulnerable to the proposed side-channel attacks using computer simulation.