• Title/Summary/Keyword: three-dimensionality

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Induction Machine Fault Detection Using Generalized Feed Forward Neural Network

  • Ghate, V.N.;Dudul, S.V.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.3
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    • pp.389-395
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    • 2009
  • Industrial motors are subject to incipient faults which, if undetected, can lead to motor failure. The necessity of incipient fault detection can be justified by safety and economical reasons. The technology of artificial neural networks has been successfully used to solve the motor incipient fault detection problem. This paper develops inexpensive, reliable, and noninvasive NN based incipient fault detection scheme for small and medium sized induction motors. Detailed design procedure for achieving the optimal NN model and Principal Component Analysis for dimensionality reduction is proposed. Overall thirteen statistical parameters are used as feature space to achieve the desired classification. GFFD NN model is designed and verified for optimal performance in fault identification on experimental data set of custom designed 2 HP, three phase 50 Hz induction motor.

An Efficient Brownian Motion Simulation Method for the Conductivity of a Digitized Composite Medium

  • Kim, In-Chan
    • Journal of Mechanical Science and Technology
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    • v.17 no.4
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    • pp.545-561
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    • 2003
  • We use the first-passage-time formulation by Torquato, Kim and Cule [J. Appl. Phys., Vol. 85, pp. 1560∼1571 (1999) ], which makes use of the first-passage region in association with the diffusion tracer's Brownian movement, and develop a new efficient Brownian motion simulation method to compute the effective conductivity of digitized composite media. By using the new method, one can remarkably enhance the speed of the Brownian walkers sampling the medium and thus reduce the computation time. In the new method, we specifically choose the first-passage regions such that they coincide with two, four, or eight digitizing units according to the dimensionality of the composite medium and the local configurations around the Brownian walkers. We first obtain explicit solutions for the relevant first-passage-time equations in two-and three-dimensions. We then apply the new method to solve the illustrative benchmark problem of estimating the effective conductivities of the checkerboard-shaped composite media. for both periodic and random configurations. Simulation results show that the new method can reduce the computation time about by an order of magnitude.

Tectonic Strategies in Architectonic Fashion Design (건축적 패션 디자인의 구조적 전략)

  • Yim, Eunhyuk
    • Journal of Fashion Business
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    • v.18 no.1
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    • pp.164-181
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    • 2014
  • As the boundary between fashion and architecture is getting blurred, the interactions of the two fields are turning out abundant as well as essential. This study investigates the tectonic strategies in architectural fashion design as a novel aesthetic in the 21st century by combining literary survey and case analysis on architecture and contemporary fashion. The tectonic strategies in the works of architectural fashion designers were categorized as follows: organic geometry, technological garment construction, and independent space. Organic geometry transforms basic geometric shapes into subtle organic forms after being thrown on the body. Technological garment construction explores the garment structure and volume by applying the structural principle of suspension and fractal geometry. Independent space refers to maintaining the firm three-dimensionality of garment structure which keeps the distance from the body, assuming the similarity to architecture.

Multiphysics response of magneto-electro-elastic beams in thermo-mechanical environment

  • Vinyas, M.;Kattimani, S.C.
    • Coupled systems mechanics
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    • v.6 no.3
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    • pp.351-367
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    • 2017
  • In this article, the multiphysics response of magneto-electro-elastic (MEE) cantilever beam subjected to thermo-mechanical loading is analysed. The equilibrium equations of the system are obtained with the aid of the principle of total potential energy. The constitutive equations of a MEE material accounting the thermal fields are used for analysis. The corresponding finite element (FE) formulation is derived and model of the beam is generated using an eight noded 3D brick element. The 3D FE formulation developed enables the representation of governing equations in all three axes, achieving accurate results. Also, geometric, constitutive and loading assumptions required to dimensionality reduction can be avoided. Numerical evaluation is performed on the basis of the derived formulation and the influence of various mechanical loading profiles and volume fractions on the direct quantities and stresses is evaluated. In addition, an attempt has been made to compare the individual effect of thermal and mechanical loading with the combined effect. It is believed that the numerical results obtained helps in accurate design and development of sensors and actuators.

The Confirmation of the Validity and Reliability of the UIS Model Toward the Public Management Information System (행정정보시스템에 대한 UIS모형의 타당성 및 유효성 검증)

    • Journal of the Korean Operations Research and Management Science Society
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    • v.22 no.1
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    • pp.141-157
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    • 1997
  • The structure and dimensionality of the User Information Satisfaction (UIS) construct is an important theoretical issue that received considerable attentions. The acceptance of UIS as a standardized instrument requires confirmation that it explains and measures the user information satisfaction construct and its component. Based on a simple of 670 respondents who participated in dealing with the Public Management Information System (PMIS), this research used a confirmatory factor analysis to test the alternavtive models of underlying factor structure and assessed the reliability and validity of these factors and items in the PMIS. The result provided a support for a revised UIS model with four first-order factors and one PMIS The result provided a support for a revised UIS model with four first-order factors and one second-order (higher-order) factor in PMIS. To cross-validata these results, the author reexamined two prior data sets. The results showed that the revised model provides better model-data fit in all three data sets.

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Composition,Dimensional Issue and Nature of Entrepreneurial Orientation (EO) Construct

  • Gupta, Rakesh;Sebastian, V.J.
    • Asia-Pacific Journal of Business
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    • v.5 no.1
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    • pp.23-31
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    • 2014
  • Entrepreneurship is considered as an important driver of economic growth, new firm creation, business rejuvenation& job creation. Over a period of time research within entrepreneurship literature has shifted from entrepreneur and his personality to his behavioral disposition. This has led to emergence of entrepreneurial orientation (EO) construct, which focuses on the process of entrepreneurship at firm level and it has emerged as the most widely researched area within entrepreneurship field. Though research in this field has been rigorous and exhaustive, still there have been concerns that researchers might have prematurely agreed on the composition, dimensionality, and nature of EO Construct. There has been considerable debate about whether EO Construct comprises three or five dimensions, about co-variance or independence of these dimensions and nature of construct whether formative or reflective. This article builds an argument about the multidimensional nature of EO construct comprising five dimensions, which vary independently and the fact that EO is better explained through formative construct rather than reflective one.

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Proposal of a New Parameter for Extra Straining Effects (이차적인 변형률효과를 나타내는 새로운 변수의 제안)

  • 명현국
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.1
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    • pp.184-192
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    • 1994
  • The parameters such as Richardson numbers or stability parameters are widely used to account for the extra straining effects due to three-dimensionality, curvature, rotation, swirl and others arising in paractical complex flows. Existing expressions for the extra strain in turbulence models such as $k-{\epsilon}$ models, however, do not satisfy the tensor invariant condition representing the coordinate indifference. In the present paper, considering the characteristics of both the mean strain rate and the mean vorticity, a new parameter to deal with the extra straining effects is proposed. The new parameter has a simple form and satisfies the tensor invariant condition. A semi-quantitative analysis between the present and previous parameters for several typical complex flows suggests that the newly proposed parameter is more general and adequate in representing the extra straining effects than the previous ad-hoc parameters.

Seismic Design Provisions and Revisions to the Guides for RC Flat Plate Systems in the US (미국에서의 RC무량판 내진설계기준과 개정 방향)

  • Kang, Thomas H.K.;Park, Hong-Gun
    • Magazine of the Korea Concrete Institute
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    • v.20 no.2
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    • pp.25-36
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    • 2008
  • Seismic design of reinforced concrete flat plate structures is often complicated as it deals with three dimensionality and continuous spans, and mostly material complexity and reinforcement variation. A great degree of uncertainty in such structural and material properties is thus inherent in the RC flat plate systems, and hinders simplification of the design process in terms of slab flexure, unbalanced moment transfer at a slab-column connection, and punching shear. For these reasons, there have been substantial changes and updates in building codes relating to flat plates and slab-column connections over a handful of decades. Also, for the same reason, some of codes never have been revised. As a consequence of nonsimultaneous development of each provision, it tends to confuse structural engineers when using a mixture of all different US code provisions. In this paper, in the step-by-step logical order, seismic design of the RC flat plate systems is re-organized and clarified to make it easier to apply. Furthermore, recent changes or proposed changes are introduced, and are explained as to how it will apply in practice.

Fingerprint Matching Based on Dimension Reduced DCT Feature Vectors

  • Bharkad, Sangita;Kokare, Manesh
    • Journal of Information Processing Systems
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    • v.13 no.4
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    • pp.852-862
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    • 2017
  • In this work a Discrete Cosine Transform (DCT)-based feature dimensionality reduced approach for fingerprint matching is proposed. The DCT is applied on a small region around the core point of fingerprint image. The performance of our proposed method is evaluated on a small database of Bologna University and two large databases of FVC2000. A dimensionally reduced feature vector is formed using only approximately 19%, 7%, and 6% DCT coefficients for the three databases from Bologna University and FVC2000, respectively. We compared the results of our proposed method with the discrete wavelet transform (DWT) method, the rotated wavelet filters (RWFs) method, and a combination of DWT+RWF and DWT+(HL+LH) subbands of RWF. The proposed method reduces the false acceptance rate from approximately 18% to 4% on DB1 (Database of Bologna University), approximately 29% to 16% on DB2 (FVC2000), and approximately 26% to 17% on DB3 (FVC2000) over the DWT based feature extraction method.

A graphical method for discriminant analysis when covariance matrices are unequal (공분산행렬이 서로 다를 경우 그래프에 의한 판별분석)

  • 김성주;정갑도
    • The Korean Journal of Applied Statistics
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    • v.6 no.2
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    • pp.409-419
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    • 1993
  • This paper concerns graphical methods for discriminant analysis. We discuss Sammon's graph, MV graph and possibility of an alternative. The properties of the three graphs are investigated using real data and simulation studies. Dimensionality reduction for an alternative and robust procedure are discussed.

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