• 한국과학교육학회지
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• 제40권1호
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• pp.13-28
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• 2020

이 연구는 대표적인 뉴미디어 매체인 유튜브 상에서 재현되고 소비되는 과학 실험의 이미지의 특성에 대해 이해하고자 했다. 특히 이 연구에서는 현대사회에서 이미지의 강력한 지위와 가상과 실재의 경계의 모호함에 대해 논의한 보드리야르의 시뮬라시옹과 시뮬라크르의 이론을 바탕으로 유튜브의 과산화수소 분해 실험 영상 사례를 분석했다. 총 14편의 국내외 과산화 수소 분해 실험 관련 유튜브 영상이 분석되었다. 연구 결과, 뉴미디어 매체 속에서 과산화 수소 분해실험은 전형적으로 과학적 실험을 의미하는 기호들과 함께 재현되고 있었으나, 가장 핵심적인 기호는 실험을 통해 생성되는 거품이었다. 콘텐츠의 더 많은 소비 촉진을 위하여 유튜브 속에서 재현되는 과산화수소 분해 실험의 거품은 더욱 자극적인 '초거대한 거품 폭발'의 이미지로 변화되어갔다. 뿐만 아니라 유튜브의 댓글을 통해 과산화수소 분해 실험을 수행하는 교실에서도 이 거대한 거품의 이미지는 실재보다 더 실재같은 시뮬라크르이며, 실제 실험의 수행에도 영향력을 미치는 시뮬라시옹이 일어남을 확인할 수 있었다. 학습자가 언제 어디서나 접근 가능하며 수많은 이미지를 제공하는 뉴미디어의 영향력을 고려할 때, 뉴미디어 속 과학실험이 학생들의 과학에 대한 친밀함과 접근성을 높인다는 점은 긍정적이다. 그러나 즉각적이고 표면적 이미지만을 주로 다루는 뉴미디어의 특성으로 인해 과학실험의 목적이 '스펙터클 이미지의 생성'으로만 고착될 위험성도 유의해야 할 것이다. 더 나아가 이 연구에서는 일상생활에 깊숙이 영향을 미치는 뉴미디어의 특성과 한계를 이해를 토대로 그 속에서 재현되고 굳어지는 과학 관련 이미지들을 비판적으로 검토하는 과학 미디어리터러시가 요구됨을 주장했다.

• Geomechanics and Engineering
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• 제23권2호
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• pp.151-163
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• 2020

Grouting method is an effective way of reinforcing cracked rock masses and plugging water gushing. Current grouting diffusion models are generally developed for horizontal cracks, which is contradictory to the fact that the crack generally occurs in rock masses with irregular spatial distribution characteristics in real underground environments. To solve this problem, this study selected a cement-sodium silicate slurry (C-S slurry) generally used in engineering as a fast-curing grouting material and regarded the C-S slurry as a Bingham fluid with time-varying viscosity for analysis. Based on the theory of fluid mechanics, and by simultaneously considering the deadweight of slurry and characteristics of non-uniform spatial distribution of viscosity of fast-curing grouts, a theoretical model of slurry diffusion in an oblique crack in rock masses at constant grouting rate was established. Moreover, the viscosity and pressure distribution equations in the slurry diffusion zone were deduced, thus quantifying the relationship between grouting pressure, grouting time, and slurry diffusion distance. On this basis, by using a 3-d finite element program in multi-field coupled software Comsol, the numerical simulation results were compared with theoretical calculation values, further verifying the effectiveness of the theoretical model. In addition, through the analysis of two engineering case studies, the theoretical calculations and measured slurry diffusion radius were compared, to evaluate the application effects of the model in engineering practice. Finally, by using the established theoretical model, the influence of cracking in rock masses on the diffusion characteristics of slurry was analysed. The results demonstrate that the inclination angle of the crack in rock masses and azimuth angle of slurry diffusion affect slurry diffusion characteristics. More attention should be paid to the actual grouting process. The results can provide references for determining grouting parameters of fast-curing grouts in engineering practice.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.146-149
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• 2003

This paper proposes the concept of “Artificial Emotion”(AE). The goal of AE is simulation, extension and expansion of natural emotion, especially human emotion. The object of AE is machine emotion and emotion machine. The contents of AE are emotion recognition, emotion measurement, emotion understanding emotion representation emotion generation, emotion processing, emotion control and emotion communication. The methodology, technology, scientific significance and application value of artificial emotion are discussed

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.237-237
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• 1999

We have observed that a stable and reproducible Negative Differential Resistance(NDR) is induced by external microwave at low power in Nb/AlO$_x$/Al/Alo$_x$/Nb junctions. To study the erratic and pozzling NDR observations we have simulated Stewart-McCumber model in the region. Experimental results and simulation results will be presented with a discussion to draw a dynamic interpreration of the NDR.

• ETRI Journal
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• 제28권4호
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• pp.506-508
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• 2006

A frequency selective surface (FSS), whose unit cell consists of a ternary tree loop loaded with a modified tripole, is proposed to block multiple frequency bands. Target frequency bands correspond to Korean personal communication services, cellular mobile communication, and 2.4 GHz industrial, scientific, and medical bands. Through the adjustment of inter-element and inter-unit cell gaps, and adjustment of the length of elements, we present an FSS design method that makes the precise tuning of multiple resonance frequencies possible. Additionally, to verify the validity of our approach, simulation results obtained from a commercial software tool and experimental data are also presented.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1998년도 춘계학술대회논문집
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• pp.134-137
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• 1998

Caliber design in bar and rod rolling depends on the designer's experience, which in general is acquired through costly trial-and-error process. As a prerequisite for developing a scientific approach to caliber design, we present a finite element model to simulate 3-D deformation of bars and rods occurring in multi-pass sequence. The results are compared with measurements obtained from POSCO for to assess the solution accuracy. The comparison shows that the simulation results agree well experiments.

• Journal of information and communication convergence engineering
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• 제2권3호
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• pp.172-176
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• 2004

In special effects industry there is a high demand to convincingly mimic the appearance and behavior of natural phenomena such as smoke, waterfall, rain, and fire. Particle systems are methods adequate for modeling fuzzy objects of natural phenomena. This paper presents particle system graphics library for generating special effects in video games and virtual reality applications. The library is a set of functions that allow c++ programs to simulate the dynamics of particles for special effects in interactive and non-interactive graphics applications, not for scientific simulation.

• Smart Structures and Systems
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• 제21권1호
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• pp.65-74
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• 2018

In this article, an analytic non-classical model for the free vibrations of nanobeams accounting for surface stress effects is developed. The classical continuum mechanics fails to capture the surface energy effects and hence is not directly applicable at nanoscale. A general beam model based on Gurtin-Murdoch continuum surface elasticity theory is developed for the analysis of thin and thick beams. Thus, surface energy has a significant effect on the response of nanoscale structures, and is associated with their size-dependent behavior. To check the validity of the present analytic solution, the numerical results are compared with those obtained in the scientific literature. The influences of beam thickness, surface density, surface residual stress and surface elastic constants on the natural frequencies of nanobeams are also investigated. It is indicated that the effect of surface stress on the vibrational response of a nanobeam is dependent on its aspect ratio and thickness.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 춘계학술대회 논문집
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• pp.57-62
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• 2003

This paper describes the design and simulation of a multivariable optimal control system for the combined speed, heading and depth control of a Semi-Autonomous Underwater Vehicle (SAUV) developed in Korea Ocean Research and Development Institute (KRODI). The SAUV is a test-bed for the evaluation of the navigation and manipulator technologies developed for a mine disposal vehicle (MDV) in military use and for a light working underwater vehicle in scientific use. The vehicle was designed to control its cruising speed, heading and depth with 4 horizontal thrusters installed at the rear of the hull. Therefore, the decoupled control methods are limited to apply to the SAUV because the thrust forces are highly coupled with the surging, yawing, and pitching motion of the vehicle. The multivariable Linear Quadratic (LQ) control method is chosen to control steering and diving in variable speed motion automatically. A series of simulation is carried out with fully nonlinear six degree of freedom dynamic model to validate the controller.

• Advances in aircraft and spacecraft science
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• 제9권5호
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• pp.367-375
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• 2022

Modeling the properties of complex alloys such as nickel superalloys is an extremely challenging scientific and engineering task. The model should take into account a large number of uncorrelated factors, for many of which information may be missing or vague. The individual contribution of one or another chemical element out of a dozen possible ligants cannot be determined by traditional methods. Moreover, there are no general analytical models describing the influence of elements on the characteristics of alloys. Artificial neural networks are one of the few statistical modeling tools that can account for many implicit correlations and establish correspondences that cannot be identified by other more familiar mathematical methods. However, such networks require careful tuning to achieve high performance, which is time-consuming. Data preprocessing can make model training much easier and faster. This article focuses on combining physics-based deep network configuration and input data engineering to simulate the solvus temperature of nickel superalloys. The used deep artificial neural network shows good simulation results. Thus, this method of numerical simulation can be easily applied to such problems.