• 제목/요약/키워드: asymmetric

검색결과 3,530건 처리시간 0.031초

다단 비축대칭 부품의 단조 공정설계를 위한 단조품설계 자동화 (Development of Automated forging Design System for Forging Process Design of Stepped Asymmetric Parts)

  • 조해용;허종행;민규식
    • 한국정밀공학회지
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    • 제17권3호
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    • pp.102-107
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    • 2000
  • This study describes computer-aided design system for stepped asymmetric forgings. To establish the appropriate process sequence, an integrated approach based on a rule-base system was accomplished. This system has four modules, which are undercut prevention module, shape cognition module, 3D modelling module and corner/fillet correction module. These modules can be used independently or at all. The proposed shape cognition method could be widely used in forging design of asymmetric parts.

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Force control of an asymmetric hydraulic cylinder for active suspensions

  • Kim, Wanil;Lee, Byung-Youn;Won, Sang-Chul
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1124-1127
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    • 1996
  • Asymmetric cylinders are usually used as an actuator of active suspensions. Since the force is influenced not only by the control but by the road roughness, force control is needed to track the desired force. But the conventional error feedback control treats the valve-cylinder dynamics at its operating point and many use the symmetric model which differ in all respects. We adopt an asymmetric cylinder model and apply a feedback linearization method for the force control to compensate both the valve nonlinearities and the effects of the road roughness.

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A FAST ASYMMETRIC KEY ENCRYPTION ALGORITHM FOR BULK DATA

  • Shin, Sang-Uk;Rhee, Kyung-Hyune
    • Journal of applied mathematics & informatics
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    • 제8권3호
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    • pp.943-957
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    • 2001
  • In this paper, we propose an efficient encryption algorithm, without exchanging session keys of a symmetric cryptosystem. The proposed scheme, called as the FAKE(Fast Asymmetric Key Encryption), first scrambles an entire input message and then encrypts small parts of the scrambled message using an asymmetric key encryption scheme. We use the all-or-nothing transform based on the hash function as a scrambling function, which was proposed by Shin, et al. Furthermore, the proposed scheme can additionally provide a digital signature service with only small overhead.

Synthesis of Novel Chiral Diamino Alcohols and Their Application in Copper-Catalyzed Asymmetric Allylic Oxidation of Cycloolefins

  • Faraji, Laleh;Samadi, Saadi;Jadidi, Khosrow;Notash, Behrouz
    • Bulletin of the Korean Chemical Society
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    • 제35권7호
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    • pp.1989-1995
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    • 2014
  • The small library of new enantiomerically pure (S,S)-diamino alcohols 1 and their hydroxyldiamide precursors 2 were conveniently synthesized on a gram scale from inexpensive and commercially chiral pool amino acids. The catalytic and induced asymmetric effects of the chiral ligands 1 in the asymmetric allylic oxidation of cycloolefins were investigated.

비대칭 건물의 거동 개선을 위한 점탄성 감쇠기의 활용에 관한 연구 (Effects of Viscoelastic Dampers on the Improvement of Torsional Response of Asymmetric Buildings)

  • 김진구;방성혁;이진수
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 가을 학술발표회논문집
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    • pp.249-256
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    • 2000
  • The visco-elastic dampers were used to improve the torsional responses of an asymmetric buildings. The modal characteristic equation of an asymmetric structure with added viscoelastic dampers were derived using the complex modal analysis method. Parametric study has been performed based on the modal characteristics, and the appropriate condition for compensating the stiffness eccentricity was investigated. According to the results the torsional response of the asymmetric buildings could be improved significantly once the dampers were properly placed

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비대칭연단보강재가 설치된 직교이방성 압축재의 탄성 국부좌굴해석 (Analysis of Elastic Local Buckling of an Orthotropic Compression Member with Asymmetric Edge Stiffeners)

  • 최원창;정상균;윤순종
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2000년도 추계학술발표대회 논문집
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    • pp.5-8
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    • 2000
  • This paper presents the analytical investigation pertaining to the local buckling behavior of orthotropic open section thin-walled compression members with asymmetric edge stiffeners. In the analysis, 3 different cases of the second moment of inertia are considered to find the asymmetric edge stiffener effect on the local buckling strength. The analytical study results are presented in the graphical form so that the edge stiffener effects on the local buckling strength can be easily found.

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A New Approach to the Synthesis of Optically Active Norephedrine, Norpseudoephedrine and Cathinone via Double Asymmetric Induction

  • Kim, Dong-Jun;Cho, Byung-Tae
    • Bulletin of the Korean Chemical Society
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    • 제24권11호
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    • pp.1641-1648
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    • 2003
  • New and facile synthetic routes for preparation of optically active norephedrine, norpseudoephedrine and cathinone with high optical purities via double asymmetric induction by employing asymmetric reduction of 2-N-protected amino (or azido)-1-phenylpropanone and 2-methanesulfonyloxy-1-phenylpropanone with CBS-catalyzed-borane and $^dIpc_2BCl$ as chiral reducing agents are described.

Rank Scores for Linear Models under Asymmetric Distributions

  • Choi, Young-Hun
    • Communications for Statistical Applications and Methods
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    • 제13권2호
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    • pp.359-368
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    • 2006
  • In this paper we derived the asymptotic relative efficiency, ARE(ms, rs), of our new score function with respect to the McKean and Sievers scores for the asymmetric error distributions which often occur in practice. We thoroughly explored the asymptotic relative efficiency, ARE(ms, rs), of our score function that provides much improvement over the McKean and Sievers scores for all values of r and s under asymmetric distributions.

NONLINEAR ASYMMETRIC LEAST SQUARES ESTIMATORS

  • Park, Seung-Hoe;Kim, Hae-Kyung;Lee, Young
    • Journal of the Korean Statistical Society
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    • 제32권1호
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    • pp.47-64
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    • 2003
  • In this paper, we consider the asymptotic properties of asymmetric least squares estimators for nonlinear regression models. This paper provides sufficient conditions for strong consistency and asymptotic normality of the proposed estimators and derives asymptotic relative efficiency of the pro-posed estimators to the regression quantile estimators. We give some examples and results of a Monte Carlo simulation to compare the asymmetric least squares estimators with the regression quantile estimators.

SOME NEW ASYMMETRIC ORTHOGONAL ARRAYS

  • Aggarwal, M.L.;Budhraja, Veena
    • Journal of the Korean Statistical Society
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    • 제32권3호
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    • pp.225-233
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    • 2003
  • In this paper we make use of the parity check matrices of the codes based on inverting construction $Y_1$ to construct a number of new asymmetric orthogonal arrays with higher strength and higher number of levels using the method of construction of asymmetric orthogonal arrays given by Suen et al. (2001).