• Title/Summary/Keyword: Interaction Model

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Research on the tightening strategy of bolted flange for contact stiffness of joint surface

  • Zuo, Weiliang;Liu, Zhifeng;Zhao, Yongsheng;Niu, Nana;Zheng, Mingpo
    • Structural Engineering and Mechanics
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    • v.83 no.3
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    • pp.341-351
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    • 2022
  • During bolted flange assembly, the contact stiffness of some areas of the joint surface may be low due to the elastic interaction. In order to improve the contact stiffness at the lowest position of bolted flange, the correlation model between the initial bolt pre-tightening force and the contact stiffness of bolted flange is established in this paper. According to the stress distribution model of a single bolt, an assumption of uniform local contact stiffness of bolted flange is made. Moreover, the joint surface is divided into the compressive stress region and the elastic interaction region. Based on the fractal contact theory, the relationship model of contact stiffness and contact force of the joint surface is proposed. Considering the elastic interaction coefficient method, the correlation model of the initial bolt pre-tightening force and the contact stiffness of bolted flange is established. This model can be employed to reverse determine the tightening strategy of the bolt group according to working conditions. As a result, this provides a new idea for the digital design of tightening strategy of bolt group for contact stiffness of bolted flange. The tightening strategy of the bolted flange is optimized by using the correlation model of initial bolt pre-tightening force and the contact stiffness of bolted flange. After optimization, the average contact stiffness of the joint surface increased by 5%, and the minimum contact stiffness increased by 6%.

Development of a three-dimensional dynamic model for chemotaxis

  • Song, Jihwan;Kim, Dongchoul
    • Interaction and multiscale mechanics
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    • v.4 no.2
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    • pp.165-171
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    • 2011
  • In this study, we proposed a three-dimensional dynamic model under the diffuse interface description for the single crawling cell. From the developed model, we described the clear evolution processes for crawling neutrophil and assessed the reliable quantitative chemotactic property, which confirmed the high possibility of adequate predictions. To establish the system considering of multiple mechanisms such as, diffusion, chemotaxis, and interaction with surface, a diffuse interface model is employed.

The Family FIRO Model for Stepfamily Development (재혼가족 발달을 위한 가족 FIRO 모델)

  • 현은민
    • Journal of Families and Better Life
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    • v.16 no.3
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    • pp.53-66
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    • 1998
  • This study presents the Family FIRO model for stepfamily development. The Family FIRO model conceptualizes interactional patterns in stepfamily for dealing with developmental tasks and suggests a method for organizing assessment and for prioritizing treatment strategies. Boundary ambiguity role confusion intergenerational coalition and loyalty conflict lack of relationship commitment and resource management issues of stepfamily constitute the inclusion interaction dimension in The Family FIRO model. While power role negotiation conflict decision making and discipline issues represent the control interaction dimension lack of emotional exchange and open self-disclosure issues are intimacy interaction dimension in the stepfamily. The family FIRO model suggests that stepfamily should attend to the developmental tasks related to inclusion before placing a major emphasis on control issues which in turn should come before emphasis on stepfamily intimacy.

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An empirical model for amplitude prediction on VIV-galloping instability of rectangular cylinders

  • Niu, Huawei;Zhou, Shuai;Chen, Zhengqing;Hua, Xugang
    • Wind and Structures
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    • v.21 no.1
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    • pp.85-103
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    • 2015
  • Aerodynamic forces of vortex-induced vibration and galloping are going to be coupled when their onset velocities are close to each other, which will induce the cross-wind amplitudes of the structures increased continuously with ever-increasing wind velocities. The main purpose of the present work is going to propose an empirical formula to predict the response amplitude of VIV-galloping interaction. Firstly, two typical mathematical models for the coupled oscillations, i.e., Tamura & Shimada model and Parkinson & Corless model are comparatively summarized. Then, the key parameter affecting response amplitude is determined through comparative numerical simulations with Tamura & Shimada model. For rectangular cylinders with the side ratio from 0.5 to 2.5, which are actually prone to develop the VIV and galloping induced interaction responses, an empirical amplitude prediction formula is proposed after regression analysis on comprehensively collected experimental data with the predetermined key parameter.

Relationship Perspective Analysis for IOS Usage (IOS 활용의 관계적 관점 분석)

  • Han, Hyun-Soo;Choi, Yong-Jin
    • Korean Management Science Review
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    • v.27 no.3
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    • pp.87-98
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    • 2010
  • In this paper, we drew upon IMP group's Interaction model to investigate the contributing impact of Inter-organizational system (IOS) on performance through enhancing inter-organizational relationship. While most extant literature studied the contribution of IOS from transaction efficiency perspective, the relational aspect of IOS contribution on the supply chain was addressed only by a few researches. As such, we intended to fill this gap of the IOS research stream. The conceptual model was developed, with reference to process theory, to analyze how the relational perspective could be applicable to IOS impact on performance. With the 129 sample data collected at the firm level,structural equation model using the LISREL was employed to validate the proposed research model. The empirical results supported the hypotheses such as the extent of IOS usage positively influences the interaction between the firms, which thereby enhances the extent of inter-firm partnership and performance. The results help better understanding the strategic use of IOS from relationship perspective.

Modeling of rain-wind induced vibrations

  • Peil, Udo;Nahrath, Niklas
    • Wind and Structures
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    • v.6 no.1
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    • pp.41-52
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    • 2003
  • Rain-wind induced vibrations of cables are a challenging problem in the design of cable-stayed bridges. The precise excitation mechanism of the complex interaction between structure, wind and rain is still unknown. A theoretical model that is able to accurately simulate the observed phenomena is not available. This paper presents a mathematical model describing rain-wind induced vibrations as movement-induced vibrations using the quasi-steady strip theory. Both, the vibrations of the cable and the movement of the water rivulet on the cable surface can be described by the model including all geometrical and physical nonlinearities. The analysis using the stability and bifurcation theory shows that the model is capable of simulating the basic phenomena of the vibrations, such as dependence of wind velocity and cable damping. The results agree well with field data and wind tunnel tests. An extensive experimental study is currently performed to calibrate the parameters of the model.

EMTP SIMULATION MODEL TO ANALYZE DYNAMIC INTERACTION BETWEEN STATCON AND TRANSMISSION SYSTEM (STATCON과 송전계통의 동적응동 분석을 위한 EMTP 시뮬레이션 모델)

  • Han, Byung-Moon
    • Proceedings of the KIEE Conference
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    • 1995.07a
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    • pp.446-448
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    • 1995
  • This paper dscribes a detail simulation model with EMTP (Electro-Magnetic Transients Program) which is very effective to analyze the interaction between the ac transmission line and STATCON (static condenser). The SATCON was represented by two voltage-source converters connected in parallel and sharing an energy storage dc capacitor bank. The voltage source converters was modeled with ideal gate turn-off switches. The power system was represented by a detail generator model and a distributed tramnsmission line model for detail performance analyses. Analysis results show that the conceived simulation model is very effective to analyze the interaction between the ac transmission line and STATCON, and to evaluate the performance of STATCON.

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Teaching Models for Scientific Inquiry Activity through the Nature of Science (NOS)

  • Park, Jong-Won
    • Journal of The Korean Association For Science Education
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    • v.28 no.7
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    • pp.759-767
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    • 2008
  • This article arose from the previous studies, which suggested a synthetic list for the nature of science (NOS), discussed the relationship between the NOS and scientific inquiry and the development of the NOS in the context of scientific inquiry. In this article, for teaching scientific inquiry through the NOS, I proposed three teaching models - reflection, interaction, and the direct model -. Within these teaching models, understanding the NOS is viewed as a prerequisite condition for the improved performance of scientific inquiry. In the reflection model, the NOS is embedded and reflected in scientific inquiry without explicit introduction or direct explanation of the NOS. In the interaction model, concrete interaction between scientific inquiry and the NOS is encouraged during the process of scientific inquiry. In the direct model, subsequent to directly comprehending the NOS at the first stage of activity, students conduct scientific inquiry based on their understanding of the NOS. The intention of this present article is to facilitate the use of these models to develop teaching materials for more authentic scientific inquiry.

A new approach on soil-structure interaction.

  • Gilbert, C.
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.101-110
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    • 2002
  • This article summarises the traditional method of soil-structure interaction based on the modulus of subgrade reaction and shows its weakness. In order to avoid these weakness, a new soil-structure interaction model is proposed. This model considers the soil as a set of connected springs which enables interaction between springs. Its use is as simple as the traditional model but allows to define the soil properties independently from the structural properties and the loading conditions. Thus, the definition of the modulus of subgrade reaction is unnecessary as each component is defined by its own modulii (Young's modulus and shear modulus). The non-linear soil behaviour for the shear stress versus distortion is also incorporated in the model. This feature allows to pinpoint the arching effect in the ground and shows how the stresses concentrate on stiff materials. Based on these principles, three dimensional program has been developed in order to solve the difficult problem of soil improvement by inclusions (stiff or soft). Also the possibility to take into account a flexible mat and/or a subgrade layer has been implemented. Equations used in the model are developed and a parametric study of the necessary data used in the program is presented. In particular, the Westergaard modulus notion and the arching effect are analysed.

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Robust Sentiment Classification of Metaverse Services Using a Pre-trained Language Model with Soft Voting

  • Haein Lee;Hae Sun Jung;Seon Hong Lee;Jang Hyun Kim
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.9
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    • pp.2334-2347
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    • 2023
  • Metaverse services generate text data, data of ubiquitous computing, in real-time to analyze user emotions. Analysis of user emotions is an important task in metaverse services. This study aims to classify user sentiments using deep learning and pre-trained language models based on the transformer structure. Previous studies collected data from a single platform, whereas the current study incorporated the review data as "Metaverse" keyword from the YouTube and Google Play Store platforms for general utilization. As a result, the Bidirectional Encoder Representations from Transformers (BERT) and Robustly optimized BERT approach (RoBERTa) models using the soft voting mechanism achieved a highest accuracy of 88.57%. In addition, the area under the curve (AUC) score of the ensemble model comprising RoBERTa, BERT, and A Lite BERT (ALBERT) was 0.9458. The results demonstrate that the ensemble combined with the RoBERTa model exhibits good performance. Therefore, the RoBERTa model can be applied on platforms that provide metaverse services. The findings contribute to the advancement of natural language processing techniques in metaverse services, which are increasingly important in digital platforms and virtual environments. Overall, this study provides empirical evidence that sentiment analysis using deep learning and pre-trained language models is a promising approach to improving user experiences in metaverse services.