• Journal of computational fluids engineering
• /
• v.8 no.1
• /
• pp.38-43
• /
• 2003

• Journal of the Korea Computer Graphics Society
• /
• v.24 no.2
• /
• pp.11-20
• /
• 2018

We propose a new method particle-based method that explicitly preserves thin liquid sheets for animating liquids on CPU-GPU heterogeneous computing framework. Our primary contribution is a particle-based framework that splits at thin points and collapses at dense points to prevent the breakup of liquid on GPU. In contrast to existing surface tracking methods, the our method does not suffer from numerical diffusion or tangles, and robustly handles topology changes on CPU-GPU framework. The thin features are detected by examining stretches of distributions of neighboring particles by performing PCA(Principle component analysis), which is used to reconstruct thin surfaces with anisotropic kernels. The efficiency of the candidate position extraction process to calculate the position of the fluid particle was rapidly improved based on the CPU-GPU heterogeneous computing techniques. Proposed algorithm is intuitively implemented, easy to parallelize and capable of producing quickly detailed thin liquid animations.

• Journal of Korea Game Society
• /
• v.14 no.6
• /
• pp.49-58
• /
• 2014

In particle-based fluid simulation, the yield stress is required for the deformation of the viscoelastic material like gel. von Mises's yield condition has been proposed to implement deformation of viscoelastic objects, but did not express the explosion. Furthermore, von Mises's yield condition is hard to approximate. We propose an ideal yield condition for viscoelastic object that reference from Tresca's yield condition. Unlike conventional particle-based simulation approximate the external power by the deformed length of the object, this paper is approximate the external power by area of the object. We check up that explosion was realistic when a viscoelastic object is compressed under the ideal yield condition.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.07a
• /
• pp.577-580
• /
• 2022

본 논문에서는 마이크로소프트(Microsoft, MS) 홀로렌즈v2를 이용하여 물리 기반 애니메이션은 유체와 로프를 제어할 수 있는 새로운 방법에 대해 소개한다. 물리 기반 시뮬레이션 혼합현실, 메타버스, 게임 등 다양한 콘텐츠에서 몰입감을 개선하기 위해 활용되고 있는 기술이다. 하지만, 계산양이 크고 사용자가로 인한 직관적인 제어 시스템의 부재로 많은 시장에 활용되기에는 어려운 구조이다. 이러한 문제를 완화하기 위해 본 논문에서는 혼합현실 환경에서 무선으로 사용자 인터페이스를 구현한 홀로렌즈v2를 이용하여 물리 애니메이션을 제어하고자 한다. 이러한 도전은 혼합현실에서도 사용자의 손동작, 음성, 눈 추적 등 다양한 인터페이스를 통해 시뮬레이션을 제어할 수 있다는 가능성을 열어줌으로써, 관련시장도 확장 될 수 있다. 본 논문에서는 대표적으로 유체와 로프 시뮬레이션을 홀로렌즈를 통해 제어하는 결과를 보여준다.

• Journal of Advanced Marine Engineering and Technology
• /
• v.39 no.6
• /
• pp.614-619
• /
• 2015

In this study, a dynamics model was developed to predict the motion performance of an Autonomous Underwater Vehicle (AUV). The dynamics model includes basic dynamic state variables of the hull and force terms to determine the motion of the AUV. The affecting terms for the forces are hydrostatic force, added mass, hydrodynamic damping, lift and drag forces. The force terms can be calculated using analytical and Computational Fluid Dynamics methods. For the underwater motion simulation, a simple PD controller was used. Also, the AUV was tested in a water tank and near sea for the partial verification of the fluid drag force coefficients and way-point tracking motions.

• Proceedings of the KSEEG Conference
• /
• 2000.04a
• /
• pp.123-123
• /
• 2000

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2024.01a
• /
• pp.399-401
• /
• 2024

본 논문에서는 텍스처 합성 기술을 활용하여 가상의 거품 패턴 텍스처를 생성하기 위한 합성 데이터 구축 방법을 소개한다. 물리 기반 유체 시뮬레이션에서 거품 표현은 2차 효과(Secondary effects)로 분류되며, 그만큼 계산량이 큰 작업이다. 게임 업계에서는 저사양 디바이스에서도 실시간으로 게임이 실행되어야 하므로 상대적으로 계산량이 큰 물리 기반 시뮬레이션을 통해 거품을 표현하기 어렵다. 대부분 사용자가 임의로 그린 거품 패턴을 화면에 매핑하여 적은 계산량을 통해 거품을 표현하지만, 시뮬레이션을 통해 만들어진 데이터가 아니기 때문에 품질을 보장하기 어렵다. 본 논문에서는 물리 기반 시뮬레이션을 통해 만들어진 거품 패턴을 텍스처 합성 기술을 통해 재생산(Reproduction)함으로써 수작업으로 그린 거품 패턴에서는 표현하기 어려운 고품질 거품 패턴 텍스처를 만들어 낸다.

• The Journal of the Korea Contents Association
• /
• v.10 no.9
• /
• pp.18-25
• /
• 2010

Computer Graphics(CG) are very important in the movie industries. Recently, many domestic CG Companies participate in a movie creation. However, most companies only use commercial tools, and do not concentrate on developing techniques. This is why they use the commercial tools in spite of its lack of functions. In this paper, we explain the importance of developing technical tools to complement the shortage of commercial tools through the previewer for fluid simulation. We present how we design and implement the previewer to specialize it for fluid simulation. Finally, we estimate our previewer's performance and discuss with result.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.5
• /
• pp.1160-1167
• /
• 2013

Web based simulation service is utilized to computationally analyze various phenomena in real world according to the progress of network and computing technology. In this paper, we present an improvement and utilization of e-AIRS (e-Science Aerospace Integrated Research System). e-AIRS, has been utilized to support web based CFD simulation service since 2008. has some problems such as stable system, pre processing, post processing. To solver this problem, we improved e-AIRS such as distributed service processing, personal simulation job assignment control, and faster data loading. After improvement, although users increase from 110 to 606, the priority of user requirements is changed from stable system to pre/post processor. User requirements and statistics about e-AIRS simulation service for each semester is analyzed to support more stable and comfortable service.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.4
• /
• pp.523-533
• /
• 2019

The convergence of engineering and IT technology has brought many changes to the industry as well as academic research. In particular, computer simulation technology has evolved to a level that can accurately simulate actual physical phenomena and analyze them in real time. In this paper, we describe the CFD technology, which is mainly used in industry, and the post processor that uses the augmented reality which is emerging as the post-processing. Research on the visualization of fluid simulation results using AR technology is actively being carried out. However, due to the large size of the result data, it is limited to researches that are published in a desktop environment. Therefore, it is limitation that needs to be reviewed in actual space. In this paper, we discuss how to solve these problems. We analyze the fluid analysis results in the post-processing, and then perform optimizing data (more than 70%)to support operation in the mobile environment. In the visualization, lightweight data is used to perform real-time tracking using cloud computing, The analysis result is matched to the screen and visualized. This allows the user to review and analyze the fluid analysis results in an efficient and immersive manner in the various spaces where the simulation is performed.