• Title/Summary/Keyword: stick model

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Structural Relationship of Variables Regarding Nurse's Preventive Action against Needle Stick Injury (간호사의 주사바늘자상 예방행위관련 변인들 간의 구조모형 분석)

  • Ju, Hyeon Jeong;Lee, Ji Hyun
    • The Journal of Korean Academic Society of Nursing Education
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    • v.21 no.2
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    • pp.168-181
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    • 2015
  • Purpose: This study was conducted to determine the factors affecting the prevention of needle stick injury. Methods: Data collection was conducted during the period July 15-31, 2013 by a self-administered questionnaire involving 220 nurses working in 7 hospitals. The data was analyzed by SPSS v18 and AMOS v18. Results: Actions by nurses to prevent needle stick injury were directly and indirectly influenced by perceived benefits, attitude toward the behavior, perceived behavioral control, and intention underlying the behavior. Specially, perceived behavioral control is verified to have not only direct influence but also indirect influence on the performance of preventive action through the intention underlying the behavior. Also, perceived benefits indirectly influence the intention toward the behavior and performance of preventive action through attitude toward the behavior and perceived behavioral control. The predictor variables in this model are 52% explicable in terms of intention of prevention action against needle stick injury, and 66% explicable in terms of performance of preventive action. Conclusion: To ensure high performance of preventive action against needle stick injury, constructing not only the solution that inspires the intention toward behavior but also a system that can positively solve and improve obstructive factors in behavioral performance is of primary importance.

Rear Drum Brake Grunt(stick-slip) Noise Improvement on Braking During Nose-dive & Return Condition (제동시 발생하는 리어 드럼브레이크 Grunt(stick-slip) Noise 개선)

  • Hong, Ilmin;Jang, Myunghoon;Kim, Sunho;Choi, Hongseok
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.9
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    • pp.781-788
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    • 2013
  • Grunt(stick-slip) noise happens between rear lining and drum on braking condition while vehicle is returning to steady position after nose-dive. The study presents a new testing and analysis methods for improving brake grunt noise on vehicle. Grunt noise is called a kind of stick slip noise with below 1 kHz frequency that is caused by the surfaces alternating between sticking to each other and sliding over each other with a corresponding change in friction force. This noise is typically come from that the static friction coefficient of surfaces is much higher than the kinetic friction coefficient. For the identification of the excitation mechanism and improvement of grunt noise, it is necessary to study variable parameters of rear drum brake systems on vehicle and to implement CAE analysis with stick slip model of drum brake. The aim of this study has been to find solution parameters throughout test result on vehicle and dynamo test. As a result of this study, it is generated from stick slip between rear lining and rear drum and it can be solved to reduce contact angle of lining with asymmetric and is effected not only brake drum strength but also rear brake size and brake factor.

Rear drum brake grunt (stick-slip) noise improvement on braking during nose-dive & return condition (제동시 발생하는 리어 드럼브레이크 grunt (stick-slip) noise 개선)

  • Hong, Ilmin;Jang, Myunghoon;Kim, Sunho;Choi, Hongseok
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2012.10a
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    • pp.743-749
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    • 2012
  • Grunt (Stick-slip) noise happens between rear lining and drum on braking condition while vehicle is returning to steady position after nose-dive. The study presents a new testing and analysis methods for improving brake grunt noise on vehicle. Grunt noise is called a kind of stick slip noise with below 1kHz frequency that is caused by the surfaces alternating between sticking to each other and sliding over each other with a corresponding change in friction force. This noise is typically come from that the static friction coefficient of surfaces is much higher than the kinetic friction coefficient. For the identification of the excitation mechanism and improvement of grunt noise, it is necessary to study variable parameters of rear drum brake systems on vehicle and to implement CAE analysis with stick slip model of drum brake. The aim of this study has been to find solution parameters throughout test result on vehicle and dynamo test. As a result of this study, it is generated from stick slip between rear lining and rear drum and it can be solved to reduce contact angle of lining with asymmetric and is effected not only brake drum strength but also rear brake size and brake factor.

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Modelling and Development of Control Algorithm of Endoscopy

  • Ma, Weichao;Lee, Sanghyuk
    • Journal of Convergence Society for SMB
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    • v.4 no.2
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    • pp.33-39
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    • 2014
  • In this paper, basic backgrounds about capsule endoscopy are introduced, and the aims and objectives are also illustrated. Methodology and mathematical model for LuGre model were investigated to analyse system characteristics. A nonlinear friction model, the stick-slip motion system based on LuGre friction model was used to simulate the motion of capsule endoscopy inside human body. Under the different situation, LuGre friction model was simulated by Matlab Simulink software. The entire cycle of motion and the influence of parameters towards to velocity are fully simulated.

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The stick-slip decomposition method for modeling large-deformation Coulomb frictional contact

  • Amaireh, Layla. K.;Haikal, Ghadir
    • Coupled systems mechanics
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    • v.7 no.5
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    • pp.583-610
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    • 2018
  • This paper discusses the issues associated with modeling frictional contact between solid bodies undergoing large deformations. The most common model for friction on contact interfaces in solid mechanics is the Coulomb friction model, in which two distinct responses are possible: stick and slip. Handling the transition between these two phases computationally has been a source of algorithmic instability, lack of convergence and non-unique solutions, particularly in the presence of large deformations. Most computational models for frictional contact have used penalty or updated Lagrangian approaches to enforce frictional contact conditions. These two approaches, however, present some computational challenges due to conditioning issues in penalty-type implementations and the iterative nature of the updated Lagrangian formulation, which, particularly in large simulations, may lead to relatively slow convergence. Alternatively, a plasticity-inspired implementation of frictional contact has been shown to handle the stick-slip conditions in a local, algorithmically efficient manner that substantially reduces computational cost and successfully avoids the issues of instability and lack of convergence often reported with other methods (Laursen and Simo 1993). The formulation of this approach, however, has been limited to the small deformations realm, a fact that severely limited its application to contact problems where large deformations are expected. In this paper, we present an algorithmically consistent formulation of this method that preserves its key advantages, while extending its application to the realm of large-deformation contact problems. We show that the method produces results similar to the augmented Lagrangian formulation at a reduced computational cost.

Model Updating of an Electric Cabinet using Shaking Table Test

  • Cui, Jintao;Cho, Sung-Gook;Kim, Doo-Kie;Koo, Ki-Young;Cho, Yang-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.04a
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    • pp.59-62
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    • 2008
  • This paper presents the procedure and the results of modal identification testing of a seismic monitoring system central processing unit cabinet for a nuclear power plant. This paper also provides a model updating for making effective analytical modeling of cabinet-type electrical equipment by comparing the test results with the analysis results. From the test results and their interpretation, modal properties (modal frequency, mode shape, and modal damping) of the specimen were satisfactorily identified. However, the analysis results may need to study further to find the effective and presentative model for the cabinet-type electrical equipment. This paper just presents the first stage of the research project "Development of dynamic behavior analysis technique of dynamic structure system" which is trying to build the lumped mass beam stick model even their results do not agree well with the test results.

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Model-Based Rolling Motion Control of an One-wheeled Robot Considering the Pitching Motion of a Gyroscopic Effect (자이로 효과의 피칭 모션을 고려한 한 바퀴 로봇의 모델 기반 롤링 모션 제어)

  • Lee, Sang-Deok;Jung, Seul
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.2
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    • pp.335-341
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    • 2016
  • In general, a yawing motion concept is used for the lateral control of one wheel robot where the gimbal system is located horizontally. In this paper, another concept of the vertically located gimbal system is presented for the same purpose. Although the vertical concept undergoes an instability more easily than the horizontal one, the pitching motion of the gyroscopic effect is considered. Firstly, the trade-off relation between two balancing concepts are investigated by comparing the gyroscopic mechanism. Secondly, the dynamic model for the problem of the proposed concept is derived using the oscillatory inverted stick model. Thirdly, the stability of the model is analyzed using the phase trajectory method. Finally, the control performance of the system by a vibration controller is simulated.

The Behavior Characteristics of Diesel Impinging Spray on the Room Temperature Impinging Disk (상온 충돌판에서의 디젤 충돌 분무의 거동 특성)

  • Cha, K.J.;Se, G.I.;Kim, D.J.
    • Journal of ILASS-Korea
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    • v.1 no.4
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    • pp.24-31
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    • 1996
  • This study addresses the behavior characteristics of diesel spray injected on the impinging disk with the room temperature. The models of impinging spray are the stick, the reflect and the wall jet model In the initiative of the fuel injection the impinging spray was the reflect model. because the momentum of droplets was very large. This model developed to the wall jet model according to the time approaches. On the low temperature disk the fuel film was made by the attachment of the droplets with low Weber number. The thickness of impinging spray was increased when the disk approached to the nozzle tip. Mathematical analysis for calculation with the behavior of impinging spray have to consider the reflecting effect and the influence of the fuel film.

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Modeling Techniques of the Complex Shear Wall Structure on a Common Foundation (공동기초상 복합 전단벽 구조물의 모델링 기법)

  • 김종수
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1997.04a
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    • pp.241-248
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    • 1997
  • The super-structure in a soil-structure interaction analysis is commonly idealized as lumped parameter system. In this study, the complex shear wall structure is modeled using three different kinds of modeling techniques : 1) full FEM comparatively as an exact solution, 2)equivalent shear spring model assuming mainly shear deformations of the wall, 3) equivalent beam-stick model made by independent static analysis. Dynamic characteristics due to three different modeling methods are compared and investigated before performing structural response analysis. The beam-stick model in comparison to shear spring model gives closer dynamic responses when compared with the full FEM, even though it requires additional unit load static analyses.

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Numerical Study of Detonation for AN based non-ideal explosives via an Eulerian multi-material method (Ammonium Nitrate 계열의 폭발물의 폭굉에 관한 연구)

  • Kim, Kihong;Lee, Jinwook;Yoh, Jaiick
    • 한국연소학회:학술대회논문집
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    • 2012.11a
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    • pp.89-91
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    • 2012
  • The numerical simulation for detonation failure of ammonium nitrate (AN) based non-ideal explosives is carried out with an accurate and state-of-the-art Eulerian method. Detonation failure is readily observed in the rate stick experiments utilizing the AN mixture explosives and the inert confinements of varying thicknesses. The composition of non-ideal explosives and thickness of the confinements influence the characteristics of detonation failure. Calculated results are compared against the experimental data of both unconfined and confined rate stick problems and provide a reliable guideline to establish a fine-tuned chemical kinetic model for detonation failure.

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