• 제목/요약/키워드: differential

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Multidimensional Differential-Linear Cryptanalysis of ARIA Block Cipher

  • Yi, Wentan;Ren, Jiongjiong;Chen, Shaozhen
    • ETRI Journal
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    • 제39권1호
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    • pp.108-115
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    • 2017
  • ARIA is a 128-bit block cipher that has been selected as a Korean encryption standard. Similar to AES, it is robust against differential cryptanalysis and linear cryptanalysis. In this study, we analyze the security of ARIA against differential-linear cryptanalysis. We present five rounds of differential-linear distinguishers for ARIA, which can distinguish five rounds of ARIA from random permutations using only 284.8 chosen plaintexts. Moreover, we develop differential-linear attacks based on six rounds of ARIA-128 and seven rounds of ARIA-256. This is the first multidimensional differential-linear cryptanalysis of ARIA and it has lower data complexity than all previous results. This is a preliminary study and further research may obtain better results in the future.

비용장 오류 정정과 궤환결합을 갖는 차동 검파 시스팀 (Differential detection systems with nonredundant error correction and feedback combining)

  • Han, Young-yeal
    • 전자공학회논문지A
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    • 제32A권5호
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    • pp.31-41
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    • 1995
  • In this paper, the relationship between k consecutive outputs of the conventional differential detector and output of differential detector with k-symbol periods delay for differential MSK and GMSK systems is investigated. It is hown that there exists periodity in modulo-2 sum and product of k successive outputs of the conventional differential detector with the output of a detector with k-symbol periods delay circuit. This relationships are used to achieve performance gains over conventional differential detection. The error rate performance of the method is carried out by computer simulation and performance improvement is achieved for differential MSK and GMSK systems.

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역미분기구학의 해 공간 (Solution Space of Inverse Differential Kinematics)

  • 강철구
    • 로봇학회논문지
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    • 제10권4호
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    • pp.230-244
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    • 2015
  • Continuous-path motion control such as resolved motion rate control requires online solving of the inverse differential kinematics for a robot. However, the solution space of the inverse differential kinematics related to Jacobian J is not well-established. In this paper, the solution space of inverse differential kinematics is analyzed through categorization of mapping conditions between joint velocities and end-effector velocity of a robot. If end-effector velocity is within the column space of J, the solution or the minimum norm solution is obtained. If it is not within the column space of J, an approximate solution by least-squares is obtained. Moreover, this paper introduces an improved mapping diagram showing orthogonality and mapping clearly between subspaces, and concrete examples numerically showing the concept of several subspaces. Finally, a solver and graphics user interface (GUI) for inverse differential kinematics are developed using MATLAB, and the solution of inverse differential kinematics using the GUI is demonstrated for a vertically articulated robot.

Effect of Outriggers on Differential Column Shortening in Tall Buildings

  • Kim, Han-Soo
    • 국제초고층학회논문집
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    • 제6권1호
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    • pp.91-99
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    • 2017
  • Special consideration should be given to differential column shortening during the design and construction of a tall building to mitigate the adverse effects caused by such shortening. The effects of the outrigger - which is conventionally used to increase the lateral stiffness of a tall building - on the differential shortening are investigated in this study. Three analysis models, a constant-section, constant-stress, and general model, are prepared, and the differential shortenings of these models with and without the outrigger are compared. The effects of connection time, sectional area, and location of the outrigger on the differential shortening are studied. The sectional area of the outrigger shows a non-linear relation in reducing the maximum differential shortening. The optimum locations of the single and dual outriggers are investigated by an exhaustive search method, and it is confirmed that a global optimum location exists. This study shows that the outrigger can be utilized to reduce the differential shortening between the interior core wall and the perimeter columns as well as to reduce the lateral displacements due to wind or earthquake loads.

인공 경량골재를 사용한 콘크리트의 부등 건조수축에 관한 실험적 연구 (An Experimental Study on The Differential Dry Shrinkage of Concrete Using Artificial Lightweight Aggregate)

  • 이창수;김영욱;림연
    • 한국재난정보학회 논문집
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    • 제6권1호
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    • pp.78-90
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    • 2010
  • Exposure to the outside, the concrete is differential moisture distribution depending on the depth. Such a differential moisture distribution causes the differential drying shrinkage in concrete structures. This thesis is researched to compare the shrinkage of lightweight concrete depending on depth to normal concrete. It is used artificial lightweight aggregate which has 20% of pre-absorb value by lightweight concrete. When water-binder ratio is 30%, average shrinkage of lightweight concrete section decreased than normal concrete, but differential shrinkage of lightweight concrete section increased. However water-binder ratio is 40% and 50% average shrinkage and differential shrinkage of lightweight concrete section decreased than normal concrete.

Research on the Security Level of µ2 against Impossible Differential cryptanalysis

  • Zhang, Kai;Lai, Xuejia;Guan, Jie;Hu, Bin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권3호
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    • pp.972-985
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    • 2022
  • In the year 2020, a new lightweight block cipher µ2 is proposed. It has both good software and hardware performance, and it is especially suitable for constrained resource environment. However, the security evaluation on µ2 against impossible differential cryptanalysis seems missing from the specification. To fill this gap, an impossible differential cryptanalysis on µ2 is proposed. In this paper, firstly, some cryptographic properties on µ2 are proposed. Then several longest 7-round impossible differential distinguishers are constructed. Finally, an impossible differential cryptanalysis on µ2 reduced to 10 rounds is proposed based on the constructed distinguishers. The time complexity for the attack is about 269.63 10-round µ2 encryptions, the data complexity is O(248), and the memory complexity is 263.57 Bytes. The reported result indicates that µ2 reduced to 10 rounds can't resist against impossible differential cryptanalysis.

A LOCAL-GLOBAL VERSION OF A STEPSIZE CONTROL FOR RUNGE-KUTTA METHODS

  • Kulikov, G.Yu
    • Journal of applied mathematics & informatics
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    • 제7권2호
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    • pp.409-438
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    • 2000
  • In this paper we develop a new procedure to control stepsize for Runge- Kutta methods applied to both ordinary differential equations and semi-explicit index 1 differential-algebraic equation In contrast to the standard approach, the error control mechanism presented here is based on monitoring and controlling both the local and global errors of Runge- Kutta formulas. As a result, Runge-Kutta methods with the local-global stepsize control solve differential of differential-algebraic equations with any prescribe accuracy (up to round-off errors)

Unknown Inputs Observer Design Via Block Pulse Functions

  • Ahn, Pius
    • Transactions on Control, Automation and Systems Engineering
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    • 제4권3호
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    • pp.205-211
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    • 2002
  • Unknown inputs observer(UIO) which is achieved by the coordinate transformation method has the differential of system outputs in the observer and the equation for unknown inputs estimation. Generally, the differential of system outputs in the observer can be eliminated by defining a new variable. But it brings about the partition of the observer into two subsystems and need of an additional differential of system outputs still remained to estimate the unknown inputs. Therefore, the block pulse function expansions and its differential operation which is a newly derived in this paper are presented to alleviate such problems from an algebraic form.

DIFFERENTIAL LEARNING AND ICA

  • Park, Seungjin
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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    • pp.162-165
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    • 2003
  • Differential learning relies on the differentiated values of nodes, whereas the conventional learning depends on the values themselves of nodes. In this paper, I elucidate the differential learning in the framework maximum likelihood learning of linear generative model with latent variables obeying random walk. I apply the idea of differential learning to the problem independent component analysis(ICA), which leads to differential ICA. Algorithm derivation using the natural gradient and local stability analysis are provided. Usefulness of the algorithm is emphasized in the case of blind separation of temporally correlated sources and is demonstrated through a simple numerical example.

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TWO-SCALE CONVERGENCE FOR PARTIAL DIFFERENTIAL EQUATIONS WITH RANDOM COEFFICIENTS

  • Pak, Hee-Chul
    • 대한수학회논문집
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    • 제18권3호
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    • pp.559-568
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    • 2003
  • We introduce the notion of two-scale convergence for partial differential equations with random coefficients that gives a very efficient way of finding homogenized differential equations with random coefficients. For an application, we find the homogenized matrices for linear second order elliptic equations with random coefficients. We suggest a natural way of finding the two-scale limit of second order equations by considering the flux term.