• 제목/요약/키워드: Derivation

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CHARACTERIZATIONS OF (JORDAN) DERIVATIONS ON BANACH ALGEBRAS WITH LOCAL ACTIONS

  • Jiankui Li;Shan Li;Kaijia Luo
    • 대한수학회논문집
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    • 제38권2호
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    • pp.469-485
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    • 2023
  • Let 𝓐 be a unital Banach *-algebra and 𝓜 be a unital *-𝓐-bimodule. If W is a left separating point of 𝓜, we show that every *-derivable mapping at W is a Jordan derivation, and every *-left derivable mapping at W is a Jordan left derivation under the condition W𝓐 = 𝓐W. Moreover we give a complete description of linear mappings 𝛿 and 𝜏 from 𝓐 into 𝓜 satisfying 𝛿(A)B* + A𝜏(B)* = 0 for any A, B ∈ 𝓐 with AB* = 0 or 𝛿(A)◦B* + A◦𝜏(B)* = 0 for any A, B ∈ 𝓐 with A◦B* = 0, where A◦B = AB + BA is the Jordan product.

Continuity of Derivations on Banach Algebras

  • Kim, Gwang Hui
    • 충청수학회지
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    • 제6권1호
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    • pp.65-69
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    • 1993
  • In this paper, we show that the module derivation D is continuous on the Banach algebra and the Silov algebra, and also that the derivation restricted by separating space and the radical on the semi prime Banach algebra is continuous.

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양자키분배와 RSA 암호를 활용한 이중키 설정 키유도함수 (Key Derivation Functions Using the Dual Key Agreement Based on QKD and RSA Cryptosystem)

  • 박호중;배민영;강주성;염용진
    • 한국통신학회논문지
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    • 제41권4호
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    • pp.479-488
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    • 2016
  • 안전한 통신 시스템을 갖추기 위해서는 안전한 암호 알고리즘의 사용과 안전한 암호키 사용이 필수적이다. 현대 암호에서는 표준화된 키유도함수(Key derivation function)를 통해 안전한 암호키를 생성한다. 최근에는 양자물리의 성질을 이용한 양자키분배(Quantum key distribution, 이하 QKD) 시스템에 대한 연구가 활발히 진행되고 있어, 현대 암호시스템의 안정성 향상에 기여할 수 있을 것으로 기대된다. 이러한 관점에서 양자 암호와 현대 암호를 결합한 이중키 설정에 대한 연구가 요구된다. 본 논문에서는 양자키분배(QKD)와 현대 암호시스템인 RSA를 조합하여 안전한 키를 생성하는 두 가지의 키유도함수를 제안한다. 또한, 시뮬레이션을 통하여 생성된 암호키의 엔트로피를 측정하는 방법으로 제안한 키유도함수의 유효성을 살펴본다.

선형 Model에 의한 소류역에 있어서의 무차원 단위도 유도에 관한 연구 (A study on the derivation of Dimensionless Unit Hydrographs by the Linear model in the small watersheds)

  • 이순혁;한중석
    • 한국농공학회지
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    • 제23권3호
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    • pp.78-87
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    • 1981
  • This study was attempted to get dimensionless unit hydrograph by linear model which can be used to the estimation of flood for the development of Agricultural water resources and laid emphasis on the application of dimensionless unit hydrographs for the ungaged watersheds by applying linear model. The results summarized through this study are as follows. 1.Peak discharge is found to be Qp= CAR (C =0. 895A-o.145) having high significance between peak discharge, Qp and effective rainfall, R within the range of small watershed area, 84 to 470km2. consequently, linearity was acknowledged between rainfall and runoff. Reasonability is confirmed for the derivation of dimensionless unit hydrograph by linear model. 2.Through mathematical analysis, formula for the derivation of dimensionless unit hydrograph was derived. qp--p=(tp--t)n-1[e-(n-1)](tp--t-1) 3.Moment method was used for the evaluation of storage constant, K and shape parameter, n for the derivation of dimensionless unit hydrograph. Storage constant, K is more closely related with the such watershed characteristics as length of main stream and slopes. On the other hand, the shape parameter, n was derived with such watershed characteristics as watershed area, river length, centroid distance of the basin and slopes. 4.Time to peak discharge, Tp could be expressed as Tp=1. 25 (√s/L)0.76 having a high significance. 5.Dimensionless unit hydrographs by linear model stood more closely to the observe dimensionless unit hydrographs On the contrary, dimensionless unit hydrographs by S.C. S. method has much difference in comparison with linear model at the falling limb of hydrographs. 6.Relative errors in the q/qp at the point of 0.8 and 1.2 for the dimensionles ratio by linear model and S. C. S. method showed to be 2.41, 1.57 and 4.0, 3.19 percent respectively to the q/qp of observed dimensionless unit hydrographs. 7.Derivation of dimensionless unit hydrograph by linear model can be accomplished by linking the two empirical formulars for storage constant, K, and shape parameter, n with derivation formular for dimensionless unit hydrograph for the ungaged small watersheds.

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