• Title/Summary/Keyword: Direct evaluation method

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The Influence of the Application Methods of Direct Analysis Method for the Evaluation of Frame Stability (골조 안정성 평가를 위한 직접해석법의 적용 방법에 따른 영향)

  • Kim, Hee-Dong
    • Journal of Korean Society of Steel Construction
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    • v.22 no.4
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    • pp.293-303
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    • 2010
  • The purpose of this study was to evaluate the influence of the methods of application of the direct analysis method, using the load amplification factor suggested by the KBC 2009 design code, for the evaluation of frame stability. For this purpose, the direct analysis method was performed for three-story-one-bay and five-story-three-bay unbraced steel frames with various notional loads, bending stiffness reductions, and factor B2s. The results of the analyses were compared with the results of the second-order inelastic analysis to evaluate the influence of the applied methods. The scale of the frame, the axial load ratio, and the axial load distribution pattern were added to the main parameters to investigate the external effects. The research results showed that the influence of the methods of application of the direct analysis method is not significant in the case of the required axial strength and the application of the additional notional loads; and that the application of the factor B2 with the story stiffness concept to the direct analysis method is appropriate for the required flexural strength.

Contingency Severity Ranking Using Direct Method in Power Systems (전력계통에 있어서 직접법을 활용한 상정사고 위험순위 결정)

  • Lee, Sang-Keun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.54 no.2
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    • pp.67-72
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    • 2005
  • This paper presents a method to select contingency ranking considering voltage security problems in power systems. Direct method which needs not the detailed knowledge of the post contingency voltage at each bus is used. Based on system operator's experience and knowledge, the membership functions for the MVAR mismatch and allowable voltage violation are justified describing linguistic representation with heuristic rules. Rule base is used for the computation of severity index for each contingency by fuzzy inference. Contingency ranking harmful to the system is formed by the index for security evaluation. Compared with 1P-1Q iteration, this algorithm using direct method and fuzzy inference shows higher computation speed and almost the same accuracy. The proposed method is applied to model system and KEPCO pratical system which consists of 311 buses and 609 lines to show its effectiveness.

Numerical Evaluation of The Rayleigh Integral Using the FFT Method for Transient Sound Radiation (FFT 방법을 이용한 음압복사에 대한 Rayleigh Integral 의 수치해석적 연구)

  • Jeon, Jae-Jin
    • The Journal of the Acoustical Society of Korea
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    • v.7 no.4
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    • pp.22-30
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    • 1988
  • In this paper, the sound radiation from a clamped circular plate in an infinite baffle is calculated by using the FFT technique. The radiated sound fields are obtained by two-dimensional fast Fourier transform method is the spatial domain instead of a direct numerical evaluation of Rayleigh integral for economy of the computation time. The computation time is consumed at least by 1/200 times of the direct numerical evaluation on the Rayleigh integral in acoustic fields. The FFT method can be applicable to any shaped geometry as well as circular plate. The FFT solution could be very powerful in predicting the near and far fields of complex structures.

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Development of Evaluation Tool for Clinical Nursing Practice Competency of Nursing students (간호학생의 임상실무수행능력 평가도구 개발)

  • Lee, Kun-Ja;Chang, Chun-Ja;Lee, Eun-Ja;Lee, Yea-Jin;Kang, Ik-Wha
    • Journal of Korean Academy of Nursing Administration
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    • v.11 no.3
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    • pp.323-333
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    • 2005
  • Purpose: The purpose of this study was to development and measure validity and reliability of evaluation tool for clinical nursing practice competency of Nursing students. Method: The participants in this study were 568 nurses who had worked for more than three years above in hospitals. A questionnaire of 79 items was administered to the nurses using a convenience sampling method. The data were collected from Sep. 12th, to Oct. 20th, 2004. Result: The derived outcome tool consisted of 6 factors of direct nursing actions and 6 factors of indirect nursing actions on the basis of 79 items. The 6 factors in direct nursing actions accounted for 76.84% of the variance and 6 factors in indirect nursing actions accounted for 79.68% of the variance on total scale. As a result of the item analysis, 79 items were selected and the internal consistency alpha coefficient was .9917. The value of Cronbach' alpha of direct nursing actions was .9640, indirect nursing actions was .9550. Conclusion: The results of this study show that useful application to the evaluation tool of clinical practice competency of Nursing students and further studies need to be done to verify clinical practice educational evaluation.

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Seismic performance evaluation of a building structure using direct displacement-based design method (직접변위설계법을 이용한 건축물의 지진응답 산정)

  • 김진구;방성혁
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2001.10a
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    • pp.569-576
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    • 2001
  • In this study a procedure for evaluation of performance point using direct displacement-based design method was developed to enhance the applicability of the method. Parametric study has been performed for the natural period of the structure, yield strength, and the stiffness after the first yield. The proposed method was also applied to a 10-story steel frame. To verify the accuracy of the result, the results from capacity spectrum analysis and time history analysis were compared. The results of the proposed method turned out to match well with the results of capacity spectrum method and the time history analysis.

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Rheological Aspect of the Plastic Energy Dissipation

  • Kim, Myung-Ho
    • Proceedings of the Korean Society of Rheology Conference
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    • 2003.05a
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    • pp.93-98
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    • 2003
  • In this paper, the main emphasis and focus will be to study and illuminate the nature of Plastic Energy Dissipation (PED) in variety of polymers. This PED term represents the heat generated during the irreversible deformation of a polymer solid. A series of experiments for various polymers have been conducted in direct measurement method and indirect evaluation method - the incremental strain stress relaxation ((ISSR) method. The experimental evidence to relate the stress relaxation and the sensible temperature rise were revealed by the series of direct method experiments.

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Effects of fashion product image preference on brand image importance and advertising factor evaluation of working women (직장여성의 패션제품이미지 선호도가 브랜드이미지 중요도 및 광고요소 평가에 미치는 영향)

  • Lee, Hyun-Jung;Lee, Kyu-Hye
    • The Research Journal of the Costume Culture
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    • v.24 no.3
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    • pp.324-335
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    • 2016
  • The fashion product image preference changes depending on one's lifestyle and personal inclination. Women want to show the fashion product image preference, often through their clothing and makeup choices. Brand image includes those elements related to the brand. Advertising is the primary method for introducing brands. This study was conducted to investigate the effects of fashion product image preference on emphasis of brand image and advertising factor evaluation targeting working women in their 20s and 30s. The fashion product image preference was s sophisticated image. Preference for a sophisticated image has a significant effect on emphasis of brand image when selecting fashion products. Emphasis of brand image has a notable effect on the brand direct advertising factor evaluation. Fashion product image preference has a significant effect on both brand's direct and indirect advertising factor evaluation. When selecting a fashion product (clothing and cosmetics), brand image importance was found to have a positive effect on a brand's direct advertising factor evaluation. Therefore, fashion companies should take advantage of their brand logo. Companies should also pay attention to clothing and product containers used in advertising to show the brand. In addition, every company should create an advertising image that represents their overall brand, by using a combination of detailed advertising factor evaluation.

Proposing a Method for Robustness Index Evaluation of the Structures Based on the Risk Analysis of Main Shock and Aftershock

  • Abdollahzadeh, Gholamreza;Faghihmaleki, Hadi
    • International journal of steel structures
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    • v.18 no.5
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    • pp.1710-1722
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    • 2018
  • Investigating remained damages from terrible earthquakes, it could be concluded that some events including explosion because of defect and failure in the building mechanical facilities or caused by gas leak, firing, aftershocks, etc., which are occurred during or a few time after the earthquake, will increase the effects of damages. In this paper, by introducing a complete risk analysis which included direct and indirect risks for earthquake (the main shock) and aftershock, the corresponding robustness index was created that called as "robustness index sequential critical events risk-based". One of the main properties of the intended robustness index is using progressive collapse percentage in its evaluation. Then, in a numerical example for a 4-storey moment resisting steel frame structure, a method is presented for obtaining all effective parameters in robustness index evaluation based on the intended risk and at last its results were reported.

SIMULATOR FOR EVALUATION OF VARIOUS FUZZY CONTROL METHODS

  • Hayashi, Kenichiro;Muta, Itsuya;Hoshino, Tsutomu;Ohtsubo, Akifumi
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.949-952
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    • 1993
  • As well-known, fuzzy control has been recognized to be of great usefulness in many engineering fields. However, the present design methods of fuzzy control systems depend on trial and error the thing that limits its usefulness. Therefore, an effective and convenient support tools for design and evaluation are greatly needed as well as the establishment of the design methods and guidling. From these backgrounds, we have developed a fuzzy control simulator[1, 2] which has various fuzzy control methods such as "direct method", "indirect method" and "fuzzy-PID method". This paper deals especially with the "direct method" function of the simulator. The simulator was developed for personal computers and programed in C language.

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Experimental Study on Tensile Strength of Straight-Line Connection Using Sleeve for Indirect Method (간접활선용 압축 슬리브를 이용한 전선 직선접속에 대한 실험적 연구)

  • Kim, Sang-Bong;Kim, Kang-Sik;Oh, Gi-Dae;Song, Won-Keun;Keum, Ui-Yeon
    • KEPCO Journal on Electric Power and Energy
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    • v.7 no.1
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    • pp.85-91
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    • 2021
  • With the social atmosphere of respect for human life and the increasing interest in safety of field workers, research and development is underway in various ways to transform direct live method into indirect live method in the field of distribution. As part of this measure, it was necessary to convert electric pole and complex facilities work from machining power distribution to indirect live operation, and install a straight connecting sleeve that connects cut wires for by-pass method, but it failed to meet the tensile strength standard when constructing a sleeve constructed by direct method. In this paper, the design factors were derived based on the case of overseas similar sleeves and the tensile strength evaluation of each variable was performed, based on the analysis of these test results, the method for securing tensile strength of straight-line access sleeves for indirect running was presented.