• Title/Summary/Keyword: Detailed theoretical analysis

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Strength Analysis of Bolt Joints for an Open Frame Structure (개방형 프레임 구조물의 볼트 조인트 강도해석)

  • Lee, Jin-Min;Lee, Min-Uk;Cho, Su-Kil;Koo, Man-Hoi;Gimm, Hak-In;Lee, Tae-Hee
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.8
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    • pp.819-825
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    • 2009
  • An open frame structure is fastened by bolt joints for strength and shock attenuation. Therefore the full finite element model of an open frame structure should be properly modeled including bolt joints for strength analysis of the frames and joint assemblies which are operated under multi-loading conditions such as driving, drop, inertia and torsional loads. Then the joints and frames must satisfy the specified allowable strength constraints. Because the full finite element model has a large number of elements to perform strength analysis, a detailed fine bolt analysis seems to be very expensive. Therefore bolts of the full finite element model are approximately modeled by coupling method to constrain degree of freedoms between adjacent nodes. However, the coupling method can exaggerate stress results at the constrained nodes. Thus a detailed bolt analysis and a theoretical/experiential formula of bolts for a worst bolt joint are performed using reaction force applied both bolt and bolt joint. Finally, the results from the two methods are compared and discussed to verify the safety of the open frame structure.

A Study on Detailed Nondisclosure Criteria for the National Assembly: Focused on National Assembly Information Disclosure Regulations (국회 비공개 대상 정보 세부 기준 연구: 「국회정보공개규정」을 중심으로)

  • Kim, Youseung
    • Journal of Korean Society of Archives and Records Management
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    • v.22 no.3
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    • pp.37-53
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    • 2022
  • This study aims to discuss the issues of the detailed criteria of information subject to nondisclosure of the current National Assembly Information Disclosure Regulations and provide alternative strategies for the issues. As a theoretical study, the relevant previous studies were analyzed, the history of the National Assembly Information Disclosure Regulations was summarized, and the legal and institutional concept of the detailed criteria was discussed. Subsequently, the detailed criteria were analyzed in three aspects, namely, composition, operation, and content. For this analysis, opinions were collected by conducting interviews with five experts related to information disclosure at the National Assembly. In conclusion, the study provides alternative strategies, including a comprehensive revision of the National Assembly Information Disclosure Regulations, the necessity of revising detailed criteria, and the formation of a temporary specialized organization for revising detailed criteria.

Strength Design of Bolt Joints for an Open Frame Structure (개방형 프레임 구조물의 볼트 조인트 강도설계)

  • Lee, Jin-Min;Lee, Min-Uk;Cho, Su-Kil;Koo, Man-Hoi;Gimm, Hak-In;Lee, Tae-Hee
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.523-528
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    • 2008
  • An open frame structure is fastened by bolt joints for strength and shock attenuation. Therefore the full finite element model of an open frame structure should be properly modeled including bolt joints for strength analysis of the frames and joint assemblies which are operated under multi-loading conditions such as driving, drop, inertia and torsional loads. Then the joints and frames must satisfy the specified allowable strength constraints. Because the full finite element model has a large number of elements to perform strength analysis, a detailed fine bolt analysis seems to be very expensive. Therefore bolts of the full finite element model are approximately modeled by constraints equations to constrain degree of freedoms between adjacent nodes. However, the constraints equation method can exaggerate stress results at the constrained nodes. Thus a detailed bolt analysis and a theoretical/experiential formula of bolts for a worst bolt joint are performed using reaction force applied both bolt and bolt joint. Finally, the results from the two methods are compared and discussed to verify the safety of the open frame structure.

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A Study on the Optimum Design and Structural Behaviors of Aluminium Extrusions (알루미늄 압출재의 구조적 거동 특성 및 최적설계에 관한 연구)

  • S.I. Seo;K.H. Son
    • Journal of the Society of Naval Architects of Korea
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    • v.35 no.1
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    • pp.88-97
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    • 1998
  • Large aluminium extrusions can be used in rolling stocks and high speed vessels to reduce weight and labor cost. As sandwich plates with corrugated core have enough strength in transverse and longitudinal direction, welding lines to connect members are reduced and transverse members to strength longitudinal members are not required. However, for proper design of aluminium extrusion plates, understanding of structural behaviors of the exclusions are necessary. In this paper, at first, detailed finite element analysis is carried out to understand structural behavior. And then, simple theoretical formulas for design purpose are proposed using the orthotropic plate theory. Shear stresses resulting from end twisting which is characteristics of deep aluminium extrusion plates can also be calculated by the simple theoretical formula. Comparison with the results by detailed finite element analysis shows good accuracy of the proposed simple formulas. The simple formulas can be useful in repetitive analysis in the initial design stage.

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A comparative study between the neural network and the winters' model in forecasting

  • Kim, Wanhee
    • Korean Management Science Review
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    • v.9 no.1
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    • pp.17-30
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    • 1992
  • This paper is organized as follows. Section 2 illustrates several applications of neural networks. Section 3 presents the theoretical aspects of the major neural network paradigms as well as the structure of the back -propagation network used in the study. Section 4 describes the experiment including data analysis, modeling, and the performance criteria followed by the detailed discussion of the experimental results. Future research avenues including advantages and limitations of neural network are presented in the last section.

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A Study on the load control using electric inertia

  • Kim, Gil-Dong;Park, Hyun-Jun;Han, Young-Jae;Jang, Dong-Yuk;Jo, Jung-Min
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.128.1-128
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    • 2001
  • A propulsion system apparatus is needed for a railroad vehicle to test and estimate propulsion performance. The electrical inertia simulator to facilitate the development and testing of propulsion systems, is presented in this paper. It is based on a vector-controlled Induction motor drive supplied from the AC mains through a double PWM converter that provides desirable features such as hi-directional power folw, nearly unity power factor and low harmonic factor at the Ac mains. A theoretical analysis is first presented, followed by a detailed simulation study to assess the overall system performance under dynamic conditions.

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Sensitivity Analysis of a Mandrel Type Fiber Optic Acoustic Sensor Using an Analytical Method (해석적 방법에 의한 맨드릴형 광-음향센서의 감도특성 분석)

  • 임종인;노용래
    • The Journal of the Acoustical Society of Korea
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    • v.19 no.3
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    • pp.92-99
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    • 2000
  • In this paper, theoretical acoustic sensitivity was derived to describe acousto-optic transduction property of the mandrel type fiber optic acoustic sensor with respect to external acoustic field. The acoustic sensitivity was analyzed in relation to both material properties and geometrical influence factors of the constitutional parts of the sensor, analytically. Validity of the theoretical results were verified through comparison with the finite element analysis results. The variation trends of the sensitivity of the sensor in relation to the studied parameters showed good agreement for the two analysis methods. According to the results, it is considered more economical to design the basic structure of the sensor with the analytic equations developed in this paper, and then to carry out further detailed analysis with the finite element method for specific points of design interest.

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A Comparative Review on Problem-& Project-based Learning and Applied Method for Engineering Education (공학교육에서 문제 및 프로젝트기반학습의 비교 고찰과 적용 방안)

  • Kim, Moon-Soo
    • Journal of Engineering Education Research
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    • v.18 no.2
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    • pp.65-76
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    • 2015
  • Despite its ineffectiveness, the dominant pedagogy for engineering education is still "chalk & talk". Meanwhile, student-centered learning models have been highlighted for strong communication, teamwork skills, deep understanding and analysis on social, environmental and economic issues as well as application of their engineering knowledge in practice. Among others, on problem- and project-based learning, this article examines theoretical background and detailed features and a comparison between both learning models including common and different features from the previous theoretical and empirical studies. It reviews some cases of where they have been practiced successfully in engineering, and further, applied strategies for engineering education are suggested.

Research on Influencing Factors of Continuous Learning Willingness in Online Art Education Based on the UTAUT Model

  • Wang, Youwang;Fang, Xiuqing
    • International Journal of Contents
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    • v.18 no.2
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    • pp.58-67
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    • 2022
  • As the Internet rapidly evolves, online learning has emerged as the third largest scenario in the field of education. Online education, different from the two traditional learning scenarios of the school and society, is characterized with broader learning types and higher freedom. In today's post-pandemic era, art education, which relies on face-to-face teaching, is of particular significance to expand online education methods. Based on the UTAUT model, this paper posits seven hypotheses about the willingness to continue learning in online art education. After collecting valid data through a questionnaire, a detailed empirical analysis was conducted via SPSS and AMOS. The results of empirical analysis show that less than half of the respondents had experienced the online art education, mirroring that this is a market worth developing. Based on the findings, learning habit does not significantly impact art learners' willingness to continue learning online. This result and other verified hypotheses are detailed in the discussion part of this paper. This study proves that UTAUT can better explain user behavior than the traditional information system model prior to the improvement, and also has strong explanatory power in the field of art education. The conclusion also posits some operational suggestions from the perspective of practitioners in this field, thereby providing a theoretical basis for art education practitioners.

The Analysis of Financial of Condition: the Features of the Application of Concentric Matric Modeless

  • Nikolaevna, Vyborova Elena
    • The Journal of Economics, Marketing and Management
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    • v.7 no.1
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    • pp.39-50
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    • 2019
  • Purpose - The article views the theoretical basis of adaptation concentric matrix models in the analysis of the financial condition of the organization. Presented the elements counting procedures in the assessment of economic stability. Research design, data, and Methodology - Used the economic indicates in the concentric matrix models. The article views the specific using the concentric matrix models in the analysis of the financial condition of the organization. Results - The concentric matrix models can be adaptation to the analysis of financial conditions of organizations and to the comparative analysis. In the process of analysis of economic stability can be used "a field of efficiency". The classical variant of methods is transformed. The detailed assessment of influence of individual factors defined the additional methods. Conclusions - In the article the methods are demonstrated on the material of organization (Hyundai Elevator Co, China Communications Construction Company).