• Title/Summary/Keyword: 4D visualization

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HP/Apollo의 퍼스널 수퍼워크스테이션 DN

  • 양금엽
    • Computational Structural Engineering
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    • v.3 no.4
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    • pp.29-34
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    • 1990
  • HP의 HP/Apollo시리즈 10000 TX(Visualization System)는 고성능 RISC그래픽을 사용한 최초의 워크스테이션으로서, 아폴로의 Multiprocessing PRISM 아키텍쳐와 강력한 3D 그래픽 엔진을 채택하고 있어, 시스템의 성능과 Image Quality, Openness 및 Flexibility를 높여줌으로써, 타 제품에 비해 탁월한 성능과 기능을 제공하고 있으며, 사용자의 투자에 대한 효과를 확실히 높여주고 있다.

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Visualizing Geographical Contexts in Social Networks

  • Lee, Yang-Won;Kim, Hyung-Joo
    • Spatial Information Research
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    • v.14 no.4 s.39
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    • pp.391-401
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    • 2006
  • We propose a method for geographically enhanced representation of social networks and implement a Web-based 3D visualization of geographical contexts in social networks. A renovated social network graph is illustrated by using two key components: (i) GWCMs (geographically weighted centrality measures) that reflect the differences in interaction intensity and spatial proximity among nodes and (ii) MSNG (map-integrated social network graph) that incorporates the GWCMs and the geographically referenced arrangement of nodes on a choroplethic map. For the integrated 3D visualization of the renovated social network graph, we employ X3D (Extensible 3D), a standard 3D authoring tool for the Web. An experimental case study of regional R&D collaboration provides a visual clue to geographical contexts in social networks including how the social centralization relates to spatial centralization.

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Effects of Stroke Change on Turbulent Kinetic Energy for the In-Cylinder Flow of a Four-Valve SI Engine (Stroke 변화가 Four-Valve SI 기관 실린더내 난류 운동에너지에 미치는 영향)

  • Yoo, S.C.
    • Journal of the Korean Society of Visualization
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    • v.9 no.4
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    • pp.16-21
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    • 2011
  • The effects of stroke change on turbulent kinetic energy for the in-cylinder flow of a four-valve SI engine were studied. For this study, the same intake manifold, head, cylinder, and the piston were used to examine turbulence characteristics in two different strokes. In-cylinder flow measurements were conducted using three dimensional LDV system. The measurement method, which simultaneously collects 3-D velocity data, allowed a evaluation of turbulent kinetic energy inside a cylinder. High levels of turbulent kinetic energy were found in regions of high shear flow, attributed to the collisions of intake flows. These specific results support the more general conclusion that the inlet conditions play the dominant role in the generation of the turbulence fields during the intake stroke. However, in the absence of two counter rotating vortices, this intake generated turbulent kinetic energy continues to decrease but at a much faster rate.

The reinterpretation and visualization for geometric methods of solving the cubic equation (삼차방정식의 기하적 해법에 대한 재조명과 시각화)

  • Kim, Hyang Sook;Kim, Yang;Park, See Eun
    • East Asian mathematical journal
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    • v.34 no.4
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    • pp.403-427
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    • 2018
  • The purpose of this paper is to reinterpret and visualize the medieval Arab's studies on the geometric methods of solving the cubic equation by utilizing Apollonius' symptom of the parabola. In particular, we investigate the results of $Kam{\bar{a}}l$ $al-D{\bar{i}}n$ ibn $Y{\bar{u}}nus$, Alhazen, Umar al-$Khayy{\bar{a}}m$ and $Al-T{\bar{u}}s{\bar{i}}$ by 4 steps(analysis, construction, proof and examination) which are called the complete solution in the constructions. This paper is available in the current middle school curriculum through dynamic geometry program(Geogebra).

Local Projective Display of Multivariate Numerical Data

  • Huh, Myung-Hoe;Lee, Yong-Goo
    • The Korean Journal of Applied Statistics
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    • v.25 no.4
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    • pp.661-668
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    • 2012
  • For displaying multivariate numerical data on a 2D plane by the projection, principal components biplot and the GGobi are two main tools of data visualization. The biplot is very useful for capturing the global shape of the dataset, by representing $n$ observations and $p$ variables simultaneously on a single graph. The GGobi shows a dynamic movie of the images of $n$ observations projected onto a sequence of unit vectors floating on the $p$-dimensional sphere. Even though these two methods are certainly very valuable, there are drawbacks. The biplot is too condensed to describe the detailed parts of the data, and the GGobi is too burdensome for ordinary data analyses. In this paper, "the local projective display(LPD)" is proposed for visualizing multivariate numerical data. Main steps of the LDP are 1) $k$-means clustering of the data into $k$ subsets, 2) drawing $k$ principal components biplots of individual subsets, and 3) sequencing $k$ plots by Hurley's (2004) endlink algorithm for cognitive continuity.

Noise Reduction for Photon Counting Imaging Using Discrete Wavelet Transform

  • Lee, Jaehoon;Kurosaki, Masayuki;Cho, Myungjin;Lee, Min-Chul
    • Journal of information and communication convergence engineering
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    • v.19 no.4
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    • pp.276-283
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    • 2021
  • In this paper, we propose an effective noise reduction method for photon counting imaging using a discrete wavelet transform. Conventional 2D photon counting imaging was used to visualize the object under dark conditions using statistical methods, such as the Poisson random process. The photons in the scene were estimated using a statistical method. However, photons which disturb the visualization and decrease the image quality may occur in the background where there is no object. Although median filters are used to reduce the noise, the noise in the scene remains. To remove the noise effectively, our proposed method uses the discrete wavelet transform, which removes the noise in the scene using a specific thresholding method that utilizes photon counting imaging characteristics. We conducted an optical experiment to demonstrate the denoising performance of the proposed method.

Development of Non-Invasive Pressure Estimation Using 3D Multi-Path Line Integration Method from Magnetic Resonance Velocimetry (MRV) (자기공명유속계 (MRV) 에서 3차원 다중경로 선적분법을 활용한 비침습적 압력예측 방법 개발)

  • Ilhoon Jang;Muhammad Hafidz Ariffudin;Simon Song
    • Journal of the Korean Society of Visualization
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    • v.21 no.2
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    • pp.14-23
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    • 2023
  • The pressure difference across stenotic blood vessels is a commonly used clinical metric for diagnosing many cardiovascular diseases. At present, most clinical pressure measurements rely solely on invasive catheterization. In this study, we propose a novel method for non-invasive pressure estimation using the incompressible Navier-Stokes equations and a 3D multi-path integration approach. We verify spatio-temporal convergence on an in-silico dataset of a cylindrical straight pipe phantom with steady and pulsatile flow fields. We then evaluate the proposed method on an in vitro dataset of reconstructed control, pre-operative, and post-operative carotid artery cases acquired from 4D flow MRI. The performance of our method is compared to existing approaches based on the pressure Poisson equation and work-energy relative pressure. The results demonstrate the proposed method's high accuracy, robustness to spatio-temporal subsampling, and reduced sensitivity to noise, highlighting its great potential for non-invasive pressure estimation.

Performance Test and Evaluations of a MEMS Microphone for the Hearing Impaired

  • Kwak, Jun-Hyuk;Kang, Hanmi;Lee, YoungHwa;Jung, Youngdo;Kim, Jin-Hwan;Hur, Shin
    • Journal of Sensor Science and Technology
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    • v.23 no.5
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    • pp.326-331
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    • 2014
  • In this study, a MEMS microphone that uses $Si_3N_4$ as the vibration membrane was produced for application as an auditory device using a sound visualization technique (sound visualization) for the hearing impaired. Two sheets of 6-inch silicon wafer were each fabricated into a vibration membrane and back plate, after which, wafer bonding was performed. A certain amount of charge was created between the bonded vibration membrane and the back plate electrodes, and a MEMS microphone that functioned through the capacitive method that uses change in such charge was fabricated. In order to evaluate the characteristics of the prepared MEMS microphone, the frequency flatness, frequency response, properties of phase between samples, and directivity according to the direction of sound source were analyzed. The MEMS microphone showed excellent flatness per frequency in the audio frequency (100 Hz-10 kHz) and a high response of at least -42 dB (sound pressure level). Further, a stable differential phase between the samples of within -3 dB was observed between 100 Hz-6 kHz. In particular, excellent omnidirectional properties were demonstrated in the frequency range of 125 Hz-4 kHz.

Nonuniformity Correction Scheme Based on 3-dimensional Visualization of MRI Images (MRI 영상의 3차원 가시화를 통한 영상 불균일성 보정 기법)

  • Kim, Hyoung-Jin;Seo, Kwang-Deok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.4
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    • pp.948-958
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    • 2010
  • Human body signals collected by the MRI system are very weak, such that they may be easily affected by either external noise or system instability while being imaged. Therefore, this paper analyzes the nonuniformity caused by a design of the RF receiving coil in a low-magnetic-field MRI system, and proposes an efficient method to improve the image uniformity. In this paper, a method for acquiring 3D bias volume data by using phantom data among various methods for correcting such nonuniformity in MRI image is proposed, such that it is possible to correct various-sized images. It is shown by simulations that images obtained by various imaging methods can be effectively corrected using single bias data.

A Study of the Relationship between 3D Model and 3D Garment Simulation

  • Kim, Yeo-Sook;Park, Hye-Won
    • Journal of the Korean Society of Clothing and Textiles
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    • v.36 no.6
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    • pp.631-640
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    • 2012
  • This research project investigates the differences of various body locations (between 3D body models) and drapes garments digitally onto 3D body models. Three different subject models will be given explication. It consisted of (1) data collection of three-dimensional scans (2) creation of 3D body representations (3) comparison of avatar shapes and measurements (4) visualization and assessment of 3D body models and their 3D virtual garments. The study tests a theory of impact by differences in avatars by pattern design. A visual inspection of avatars showed clear differences between the six avatar types (in the generating process); however, there was notably less difference between 3D garment simulations based upon the six avatars produced. This demonstrated that there was less influence on the 3D garments than was predicted after a visual inspection of the avatars.