• Title/Summary/Keyword: unified theory

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THE CURVATURE TENSORS IN THE EINSTEIN'S $^*g$-UNIFIED FIELD THEORY II. THE CONTRACTED SE-CURVATURE TENSORS OF $^*g-SEX_n$

  • Chung, Kyung-Tae;Chung, Phil-Ung;Hwang, In-Ho
    • Bulletin of the Korean Mathematical Society
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    • v.35 no.4
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    • pp.641-652
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    • 1998
  • Chung and et al. ([2].1991) introduced a new concept of a manifold, denoted by $^{\ast}g-SEX_n$, in Einstein's n-dimensional $^{\ast}g$-unified field theory. The manifold $^{\ast}g-SEX_n$ is a generalized n-dimensional Riemannian manifold on which the differential geometric structure is imposed by the unified field tensor $^{\ast}g^{\lambda \nu}$ through the SE-connection which is both Einstein and semi-symmetric. In this paper, they proved a necessary and sufficient condition for the unique existence of SE-connection and sufficient condition for the unique existence of SE-connection and presented a beautiful and surveyable tensorial representation of the SE-connection in terms of the tensor $^{\ast}g^{\lambda \nu}$. Recently, Chung and et al.([3],1998) obtained a concise tensorial representation of SE-curvature tensor defined by the SE-connection of $^{\ast}g-SEX_n$ and proved deveral identities involving it. This paper is a direct continuations of [3]. In this paper we derive surveyable tensorial representations of constracted curvature tensors of $^{\ast}g-SEX_n$ and prove several generalized identities involving them. In particular, the first variation of the generalized Bianchi's identity in $^{\ast}g-SEX_n$, proved in theorem (2.10a), has a great deal of useful physical applications.

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n-DIMENSIONAL CONSIDERATIONS OF EINSTEIN'S CONNECTION FOR THE THIRD CLASS

  • Hwang, In-Ho
    • Journal of applied mathematics & informatics
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    • v.6 no.2
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    • pp.575-588
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    • 1999
  • Lower dimensional cases of Einstein's connection were al-ready investigated by many authors for n =2,4. This paper is to ob-tain a surveyable tensorial representation of n-dimensional Einstein's connection in terms of the unified field tensor with main emphasis on the derivation of powerful and useful recurrence relations which hold in n-dimensional Einstein's unified field theory(i.e., n-*g-UFT): All con-siderations in this paper are restricted to the third class only.

A Study on Strain Rate Sensitivity by Unified Viscoplasticity (점소성 이론에 의한 변형률 속도 민감도에 대한 연구)

  • 호괄수
    • Transactions of Materials Processing
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    • v.13 no.7
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    • pp.600-607
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    • 2004
  • This paper addresses a viscoplastic constitutive model that allows a consistent way of modeling positive and negative rate sensitivities of flow stress concerned with dynamic strain aging. Based on the concept of continuum mechanics, a phenomenological constitutive model includes the use of a yield surface within the framework of unified viscoplasticity theory. To model negative rate sensitivity, rate-dependent back stress is introduced and flow stress in fully developed inelastic deformation regime is thus decomposed into the plastic contribution of rate independency and the viscous one of rate dependency.

A PARTICULAR SOLUTION OF THE EINSTEIN'S EQUATION IN EVEN-DIMENSIONAL UFT Xn

  • Lee, Jong Woo
    • Journal of the Chungcheong Mathematical Society
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    • v.23 no.2
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    • pp.185-195
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    • 2010
  • In the unified field theory(UFT), in order to find a solution of the Einstein's equation it is necessary and sufficient to study the torsion tensor. The main goal in the present paper is to obtain, using a given torsion tensor (3.1), the complete representation of a particular solution of the Einstein's equation in terms of the basic tensor $g_{{\lambda}{\nu}}$ in even-dimensional UFT $X_n$.

Theoretical Models of Causative Factors in Depression : A Review of the Literature for Nursing (우울 발생요인에 관한 이론적 고찰)

  • 김수지;고성희
    • Journal of Korean Academy of Nursing
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    • v.19 no.2
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    • pp.173-190
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    • 1989
  • This literature review was undertaken to explore theoretical models of depression for their potential usefulness in nursing research and practice. Depression has bean accounted for by numerous theories or models of causation ; 11 theories selected from psychology, medicine and psychoanalysis and supported by empirical or experimental research were reviewed. These theories identify a variety of precipitating and predisposing factors that may affect the individual's depression. Aggression - turned - inward theory, object loss theory, ego functioning theory, personality organization theory, behavioral theory, learned helplessness theory, cognitive theory, genetic factors, and biological theories conceptualize predisposing factors. Only life stressors theory identifies precipitating facotrs. Each of these theories contributes to an understanding of depression, but many of them use overlapping and interrelated factors. It is also evident from recent. research that there are multiple causes for depression involving an interactive effect among predisposing and precipitating factors that are both biological and psychological in origin. That is, a single theory is not useful, but perhaps a unified theory could be developed that would be helpful to nursing. This review points to the need for continuing development and testing of theories that would integrate the multiple conceptualizations of depression.

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