Dynamic Stall Analysis Utilizing Interactive Computer Graphics
1988-03-01
Blade-Vortex Interaction (BV[) studies. solkes the two-dimen i,)nal, unsteady, compressible Euler and Napier -Stokes equations in strong conservation...requirements, interactive computer graphics workstations have been evolved to complement the super -computer. Workstation capabilities, in terms of
Intelligent Computer Graphics 2012
Miaoulis, Georgios
2013-01-01
In Computer Graphics, the use of intelligent techniques started more recently than in other research areas. However, during these last two decades, the use of intelligent Computer Graphics techniques is growing up year after year and more and more interesting techniques are presented in this area. The purpose of this volume is to present current work of the Intelligent Computer Graphics community, a community growing up year after year. This volume is a kind of continuation of the previously published Springer volumes “Artificial Intelligence Techniques for Computer Graphics” (2008), “Intelligent Computer Graphics 2009” (2009), “Intelligent Computer Graphics 2010” (2010) and “Intelligent Computer Graphics 2011” (2011). Usually, this kind of volume contains, every year, selected extended papers from the corresponding 3IA Conference of the year. However, the current volume is made from directly reviewed and selected papers, submitted for publication in the volume “Intelligent Computer Gr...
The computer graphics metafile
Henderson, LR; Shepherd, B; Arnold, D B
1990-01-01
The Computer Graphics Metafile deals with the Computer Graphics Metafile (CGM) standard and covers topics ranging from the structure and contents of a metafile to CGM functionality, metafile elements, and real-world applications of CGM. Binary Encoding, Character Encoding, application profiles, and implementations are also discussed. This book is comprised of 18 chapters divided into five sections and begins with an overview of the CGM standard and how it can meet some of the requirements for storage of graphical data within a graphics system or application environment. The reader is then intr
The computer graphics interface
Steinbrugge Chauveau, Karla; Niles Reed, Theodore; Shepherd, B
2014-01-01
The Computer Graphics Interface provides a concise discussion of computer graphics interface (CGI) standards. The title is comprised of seven chapters that cover the concepts of the CGI standard. Figures and examples are also included. The first chapter provides a general overview of CGI; this chapter covers graphics standards, functional specifications, and syntactic interfaces. Next, the book discusses the basic concepts of CGI, such as inquiry, profiles, and registration. The third chapter covers the CGI concepts and functions, while the fourth chapter deals with the concept of graphic obje
Space Spurred Computer Graphics
1983-01-01
Dicomed Corporation was asked by NASA in the early 1970s to develop processing capabilities for recording images sent from Mars by Viking spacecraft. The company produced a film recorder which increased the intensity levels and the capability for color recording. This development led to a strong technology base resulting in sophisticated computer graphics equipment. Dicomed systems are used to record CAD (computer aided design) and CAM (computer aided manufacturing) equipment, to update maps and produce computer generated animation.
Publication-quality computer graphics
Energy Technology Data Exchange (ETDEWEB)
Slabbekorn, M.H.; Johnston, R.B. Jr.
1981-01-01
A user-friendly graphic software package is being used at Oak Ridge National Laboratory to produce publication-quality computer graphics. Close interaction between the graphic designer and computer programmer have helped to create a highly flexible computer graphics system. The programmer-oriented environment of computer graphics has been modified to allow the graphic designer freedom to exercise his expertise with lines, form, typography, and color. The resultant product rivals or surpasses that work previously done by hand. This presentation of computer-generated graphs, charts, diagrams, and line drawings clearly demonstrates the latitude and versatility of the software when directed by a graphic designer.
Mathematical structures for computer graphics
Janke, Steven J
2014-01-01
A comprehensive exploration of the mathematics behind the modeling and rendering of computer graphics scenes Mathematical Structures for Computer Graphics presents an accessible and intuitive approach to the mathematical ideas and techniques necessary for two- and three-dimensional computer graphics. Focusing on the significant mathematical results, the book establishes key algorithms used to build complex graphics scenes. Written for readers with various levels of mathematical background, the book develops a solid foundation for graphics techniques and fills in relevant grap
Computer graphics in engineering education
Rogers, David F
2013-01-01
Computer Graphics in Engineering Education discusses the use of Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) as an instructional material in engineering education. Each of the nine chapters of this book covers topics and cites examples that are relevant to the relationship of CAD-CAM with engineering education. The first chapter discusses the use of computer graphics in the U.S. Naval Academy, while Chapter 2 covers key issues in instructional computer graphics. This book then discusses low-cost computer graphics in engineering education. Chapter 4 discusses the uniform b
Defining Dynamic Graphics by a Graphical Language
Institute of Scientific and Technical Information of China (English)
毛其昌; 戴汝为
1991-01-01
A graphical language which can be used for defining dynamic picture and applying control actions to it is defined with an expanded attributed grammar.Based on this a system is built for developing the presentation of application data of user interface.This system provides user interface designers with a friendly and high efficient programming environment.
Fractal geometry and computer graphics
Sakas, Georgios; Peitgen, Heinz-Otto; Englert, Gabriele
1992-01-01
Fractal geometry has become popular in the last 15 years, its applications can be found in technology, science, or even arts. Fractal methods and formalism are seen today as a general, abstract, but nevertheless practical instrument for the description of nature in a wide sense. But it was Computer Graphics which made possible the increasing popularity of fractals several years ago, and long after their mathematical formulation. The two disciplines are tightly linked. The book contains the scientificcontributions presented in an international workshop in the "Computer Graphics Center" in Darmstadt, Germany. The target of the workshop was to present the wide spectrum of interrelationships and interactions between Fractal Geometry and Computer Graphics. The topics vary from fundamentals and new theoretical results to various applications and systems development. All contributions are original, unpublished papers.The presentations have been discussed in two working groups; the discussion results, together with a...
Fluid simulation for computer graphics
Bridson, Robert
2008-01-01
Animating fluids like water, smoke, and fire using physics-based simulation is increasingly important in visual effects, in particular in movies, like The Day After Tomorrow, and in computer games. This book provides a practical introduction to fluid simulation for graphics. The focus is on animating fully three-dimensional incompressible flow, from understanding the math and the algorithms to the actual implementation.
Data structures, computer graphics, and pattern recognition
Klinger, A; Kunii, T L
1977-01-01
Data Structures, Computer Graphics, and Pattern Recognition focuses on the computer graphics and pattern recognition applications of data structures methodology.This book presents design related principles and research aspects of the computer graphics, system design, data management, and pattern recognition tasks. The topics include the data structure design, concise structuring of geometric data for computer aided design, and data structures for pattern recognition algorithms. The survey of data structures for computer graphics systems, application of relational data structures in computer gr
Wang Tiles in Computer Graphics
Lagae, Ares
2009-01-01
Many complex signals in computer graphics, such as point distributions and textures, cannot be efficiently synthesized and stored. This book presents tile-based methods based on Wang tiles and corner tiles to solve both these problems. Instead of synthesizing a complex signal when needed, the signal is synthesized beforehand over a small set of Wang tiles or corner tiles. Arbitrary large amounts of that signal can then efficiently be generated when needed by generating a stochastic tiling, and storing only a small set of tiles reduces storage requirements. A tile-based method for generating a
CELLULAR AUTOMATA AND COMPUTER GRAPHICS
Directory of Open Access Journals (Sweden)
Şen ÇAKIR
1999-01-01
Full Text Available Cellular Automata (CA are simple mathematical systems which provide models for a variety of physical processes. They show how minute changes and simple rules lead to enormous changes in the behaviour of a system. They can also be used as computer graphics tools to produce a rich reservoir of interesting figures. In recent years, CA have attracked the attention of many scientists. Today, CA are used in many fields from ecology to image processing. In this paper, it is shown that a large number of complex and interesting patterns can be created with relatively simple CA rules.
Recent progress and challenges in exploiting graphics processors in computational fluid dynamics
Niemeyer, Kyle E
2014-01-01
The progress made in accelerating simulations of fluid flow using GPUs, and the challenges that remain, are surveyed. The review first provides an introduction to GPU computing and programming, and discusses various considerations for improved performance. Case studies comparing the performance of CPU- and GPU- based solvers for the Laplace and incompressible Navier-Stokes equations are performed in order to demonstrate the potential improvement even with simple codes. Recent efforts to accelerate CFD simulations using GPUs are reviewed for laminar, turbulent, and reactive flow solvers. Also, GPU implementations of the lattice Boltzmann method are reviewed. Finally, recommendations for implementing CFD codes on GPUs are given and remaining challenges are discussed, such as the need to develop new strategies and redesign algorithms to enable GPU acceleration.
Dynamic Load Balancing using Graphics Processors
Directory of Open Access Journals (Sweden)
R Mohan
2014-04-01
Full Text Available To get maximum performance on the many-core graphics processors, it is important to have an even balance of the workload so that all processing units contribute equally to the task at hand. This can be hard to achieve when the cost of a task is not known beforehand and when new sub-tasks are created dynamically during execution. Both the dynamic load balancing methods using Static task assignment and work stealing using deques are compared to see which one is more suited to the highly parallel world of graphics processors. They have been evaluated on the task of simulating a computer move against the human move, in the famous four in a row game. The experiments showed that synchronization can be very expensive, and those new methods which use graphics processor features wisely might be required.
Hardware accelerated computer graphics algorithms
Rhodes, DT
2008-01-01
The advent of shaders in the latest generations of graphics hardware, which has made consumer level graphics hardware partially programmable, makes now an ideal time to investigate new graphical techniques and algorithms as well as attempting to improve upon existing ones. This work looks at areas of current interest within the graphics community such as Texture Filtering, Bump Mapping and Depth of Field simulation. These are all areas which have enjoyed much interest over the history of comp...
Mathematics and Computer Graphic Design Arts
Institute of Scientific and Technical Information of China (English)
徐亚非
2001-01-01
The relationship between arts and mathematics is very close, computer graphic design is based on digital methodology. The paper reveals the mathematical backgrounds behind graphic design by the example of computer-aided cubic modeling and mathematical exchange methodology. Furthermore, one can get incredible artistic effects if computer graphic designers pay more attention to the probability and use probable numbers and fractal operation in their design activities.Finally, the author also discusses the bidirections between arts and mathematics.
Computer Graphics in ChE Education.
Reklaitis, G. V.; And Others
1983-01-01
Examines current uses and future possibilities of computer graphics in chemical engineering, discussing equipment needs, maintenance/manpower costs, and plan to implement computer graphics into existing programs. The plan involves matching fund equipment grants, grants for development of computer assisted instructional (CAI) software, chemical…
Computer Graphics in ChE Education.
Reklaitis, G. V.; And Others
1983-01-01
Examines current uses and future possibilities of computer graphics in chemical engineering, discussing equipment needs, maintenance/manpower costs, and plan to implement computer graphics into existing programs. The plan involves matching fund equipment grants, grants for development of computer assisted instructional (CAI) software, chemical…
A Sporting Look at Computer Graphics.
Mattson, Merry B.
1984-01-01
Suggests having students design a football field (looking at it from above) as the final project of a unit on computer graphics. Includes listings for 13 short Applesoft programs (involving LO- and HI-RES graphics) which students can use in making the field. Advanced students can use the animation techniques. (JN)
A Codesign Case Study in Computer Graphics
DEFF Research Database (Denmark)
Brage, Jens P.; Madsen, Jan
1994-01-01
The paper describes a codesign case study where a computer graphics application is examined with the intention to speed up its execution. The application is specified as a C program, and is characterized by the lack of a simple compute-intensive kernel. The hardware/software partitioning is based...
Codesign Analysis of a Computer Graphics Application
DEFF Research Database (Denmark)
Madsen, Jan; Brage, Jens P.
1996-01-01
This paper describes a codesign case study where a computer graphics application is examined with the intention to speed up its execution. The application is specified as a C program, and is characterized by the lack of a simple compute-intensive kernel. The hardware/software partitioning is based...
12th International Conference on Computer Graphics Theory and Applications
2017-01-01
The International Conference on Computer Graphics Theory and Applications aims at becoming a major point of contact between researchers, engineers and practitioners in Computer Graphics. The conference will be structured along five main tracks, covering different aspects related to Computer Graphics, from Modelling to Rendering, including Animation, Interactive Environments and Social Agents In Computer Graphics.
Flow simulations using particles - Bridging Computer Graphics and CFD
Koumoutsakos, Petros; Cottet, Georges-Henri; Rossinelli, Diego
2008-01-01
International audience; The simulation of fluid flows using particles is becoming increasingly popular in Computer Graphics (CG). The grid-free character of particles, the flexibility in handling complex flow configurations and the possibility to obtain visually realistic results with a small number of computational elements are some of the main reasons for the success of these methods. In the Computational Fluid Dynamics (CFD) community, the realization that by periodically regularizing the ...
Applications of Computer Graphics in Engineering
1975-01-01
Various applications of interactive computer graphics to the following areas of science and engineering were described: design and analysis of structures, configuration geometry, animation, flutter analysis, design and manufacturing, aircraft design and integration, wind tunnel data analysis, architecture and construction, flight simulation, hydrodynamics, curve and surface fitting, gas turbine engine design, analysis, and manufacturing, packaging of printed circuit boards, spacecraft design.
Exploring spatial data representation with dynamic graphics
Dykes, Jason A.
1997-05-01
Dynamic mapping capabilities are providing enormous potential for visualizing spatial data. Dynamic maps which exhibit observer-related behaviour are particularly appropriate for exploratory analysis, where multiple, short-term, slightly different, views of a data set, each produced with a specific task or question in mind, are an essential part of the analytical process. This paper and the associated coloured and dynamic illustrations take advantage of World Wide Web (WWW) delivery and the digital medium by using interactive graphics to introduce an approach to dynamic cartography based upon the Tcl/Tk graphical user interface (GUI) builder. Generic ways of programming observer-related behaviour, such as brushing, dynamic re-expression, and dynamic comparison, are outlined and demonstrated to show that specialist dynamic views can be developed rapidly in an open, flexible, and high-level graphic environment. Such an approach provides opportunities to reinforce traditional cartographic and statistical representations of spatial data with dynamic graphics and transient symbolism which give supplementary information about a symbol or statistic on demand. A series of examples from recent work which uses the approach demonstrates ways in which dynamic graphics can be effective in complementing methods of measurement and mapping which are well established in geographic enquiry.
Computer Corner: Computer Graphics for the Vibrating String.
Smith, David A.; Cunningham, R. Stephen
1986-01-01
Computer graphics are used to display the sum of the first few terms of the series solution for the problem of the vibrating string frequently discussed in introductory courses on differential equations. (MNS)
Making and using shaders in modern computer graphics
2012-01-01
In the area of consumer computer graphic was a major turning point in the development of graphics and it's rendering, when new graphic cards with programmable pipeline emerged. What and how something will be done in a single stage of programmable pipeline is provided with a small program called shader. The aim of the thesis is to present the basics of modern computer graphics and use of shaders in computer graphics. We start by presenting the theoretical basis of shaders and comparing program...
Computer graphics techniques and computer-generated movies
Holzman, Robert E.; Blinn, James F.
1988-04-01
The JPL Computer Graphics Laboratory (CGL) has been using advanced computer graphics for more than ten years to simulate space missions and related activities. Applications have ranged from basic computer graphics used interactively to allow engineers to study problems, to sophisticated color graphics used to simulate missions and produce realistic animations and stills for use by NASA and the scientific press. In addition, the CGL did the computer animation for ``Cosmos'', a series of general science programs done for Public Television in the United States by Carl Sagan and shown world-wide. The CGL recently completed the computer animation for ``The Mechanical Universe'', a series of fifty-two half-hour elementary physics lectures, led by Professor David Goodstein of the California Institute of Technology, and now being shown on Public Television in the US. For this series, the CGL produced more than seven hours of computer animation, averaging approximately eight minutes and thirty seconds of computer animation per half-hour program. Our aim at the JPL Computer Graphics Laboratory (CGL) is the realistic depiction of physical phenomena, that is, we deal primarily in ``science education'' rather than in scientific research. Of course, our attempts to render physical events realistically often require the development of new capabilities through research or technology advances, but those advances are not our primary goal.
Accelerating glassy dynamics using graphics processing units
Colberg, Peter H
2009-01-01
Modern graphics hardware offers peak performances close to 1 Tflop/s, and NVIDIA's CUDA provides a flexible and convenient programming interface to exploit these immense computing resources. We demonstrate the ability of GPUs to perform high-precision molecular dynamics simulations for nearly a million particles running stably over many days. Particular emphasis is put on the numerical long-time stability in terms of energy and momentum conservation. Floating point precision is a crucial issue here, and sufficient precision is maintained by double-single emulation of the floating point arithmetic. As a demanding test case, we have reproduced the slow dynamics of a binary Lennard-Jones mixture close to the glass transition. The improved numerical accuracy permits us to follow the relaxation dynamics of a large system over 4 non-trivial decades in time. Further, our data provide evidence for a negative power-law decay of the velocity autocorrelation function with exponent 5/2 in the close vicinity of the transi...
Codesign Analysis of a Computer Graphics Application
DEFF Research Database (Denmark)
Madsen, Jan; Brage, Jens P.
1996-01-01
This paper describes a codesign case study where a computer graphics application is examined with the intention to speed up its execution. The application is specified as a C program, and is characterized by the lack of a simple compute-intensive kernel. The hardware/software partitioning is based...... on information obtained from software profiling and the resulting design is validated through cosimulation. The achieved speed-up is estimated based on an analysis of profiling information from different sets of input data and various architectural options....
Introductory Tiling Theory for Computer Graphics
Kaplan, Craig
2009-01-01
Tiling theory is an elegant branch of mathematics that has applications in several areas of computer science. The most immediate application area is graphics, where tiling theory has been used in the contexts of texture generation, sampling theory, remeshing, and of course the generation of decorative patterns. The combination of a solid theoretical base (complete with tantalizing open problems), practical algorithmic techniques, and exciting applications make tiling theory a worthwhile area of study for practitioners and students in computer science. This synthesis lecture introduces the math
Factorial graphical lasso for dynamic networks
Wit, E C
2012-01-01
Dynamic networks models describe a growing number of important scientific processes, from cell biology and epidemiology to sociology and finance. There are many aspects of dynamical networks that require statistical considerations. In this paper we focus on determining network structure. Estimating dynamic networks is a difficult task since the number of components involved in the system is very large. As a result, the number of parameters to be estimated is bigger than the number of observations. However, a characteristic of many networks is that they are sparse. For example, the molecular structure of genes make interactions with other components a highly-structured and therefore sparse process. Penalized Gaussian graphical models have been used to estimate sparse networks. However, the literature has focussed on static networks, which lack specific temporal constraints. We propose a structured Gaussian dynamical graphical model, where structures can consist of specific time dynamics, known presence or abse...
Practical algorithms for 3D computer graphics
Ferguson, R Stuart
2013-01-01
""A valuable book to accompany any course that mixes the theory and practice of 3D graphics. The book's web site has many useful programs and code samples.""-Karen Rafferty, Queen's University, Belfast""The topics covered by this book are backed by the OpenFX modeling and animation software. This is a big plus in that it provides a practical perspective and encourages experimentation. … [This] will offer students a more interesting and hands-on learning experience, especially for those wishing to pursue a career in computer game development.""-Naganand Madhavapeddy, GameDeveloper>
Facial reconstruction using 3-D computer graphics.
Vanezi, P; Vanezis, M; McCombe, G; Niblett, T
2000-02-14
Facial reconstruction using 3-D computer graphics is being used in our institute as a routine procedure in forensic cases as well as for skulls of historical and archaeological interest. Skull and facial data from living subjects is acquired using an optical laser scanning system. For the production of the reconstructed image, we employ facial reconstruction software which is constructed using the TCL/Tk scripting language, the latter making use of the C3D system. The computer image may then be exported to enable the production of a solid model, employing, for example, stereolithography. The image can also be modified within an identikit system which allows the addition of facial features as appropriate.
SPACEBAR: Kinematic design by computer graphics
Ricci, R. J.
1975-01-01
The interactive graphics computer program SPACEBAR, conceived to reduce the time and complexity associated with the development of kinematic mechanisms on the design board, was described. This program allows the direct design and analysis of mechanisms right at the terminal screen. All input variables, including linkage geometry, stiffness, and applied loading conditions, can be fed into or changed at the terminal and may be displayed in three dimensions. All mechanism configurations can be cycled through their range of travel and viewed in their various geometric positions. Output data includes geometric positioning in orthogonal coordinates of each node point in the mechanism, velocity and acceleration of the node points, and internal loads and displacements of the node points and linkages. All analysis calculations take at most a few seconds to complete. Output data can be viewed at the scope and also printed at the discretion of the user.
Mathematical basics of motion and deformation in computer graphics
Anjyo, Ken
2014-01-01
This synthesis lecture presents an intuitive introduction to the mathematics of motion and deformation in computer graphics. Starting with familiar concepts in graphics, such as Euler angles, quaternions, and affine transformations, we illustrate that a mathematical theory behind these concepts enables us to develop the techniques for efficient/effective creation of computer animation. This book, therefore, serves as a good guidepost to mathematics (differential geometry and Lie theory) for students of geometric modeling and animation in computer graphics. Experienced developers and researcher
Advanced Certification Program for Computer Graphic Specialists. Final Performance Report.
Parkland Coll., Champaign, IL.
A pioneer program in computer graphics was implemented at Parkland College (Illinois) to meet the demand for specialized technicians to visualize data generated on high performance computers. In summer 1989, 23 students were accepted into the pilot program. Courses included C programming, calculus and analytic geometry, computer graphics, and…
General aviation design synthesis utilizing interactive computer graphics
Galloway, T. L.; Smith, M. R.
1976-01-01
Interactive computer graphics is a fast growing area of computer application, due to such factors as substantial cost reductions in hardware, general availability of software, and expanded data communication networks. In addition to allowing faster and more meaningful input/output, computer graphics permits the use of data in graphic form to carry out parametric studies for configuration selection and for assessing the impact of advanced technologies on general aviation designs. The incorporation of interactive computer graphics into a NASA developed general aviation synthesis program is described, and the potential uses of the synthesis program in preliminary design are demonstrated.
Computer graphics application in the engineering design integration system
Glatt, C. R.; Abel, R. W.; Hirsch, G. N.; Alford, G. E.; Colquitt, W. N.; Stewart, W. A.
1975-01-01
The computer graphics aspect of the Engineering Design Integration (EDIN) system and its application to design problems were discussed. Three basic types of computer graphics may be used with the EDIN system for the evaluation of aerospace vehicles preliminary designs: offline graphics systems using vellum-inking or photographic processes, online graphics systems characterized by direct coupled low cost storage tube terminals with limited interactive capabilities, and a minicomputer based refresh terminal offering highly interactive capabilities. The offline line systems are characterized by high quality (resolution better than 0.254 mm) and slow turnaround (one to four days). The online systems are characterized by low cost, instant visualization of the computer results, slow line speed (300 BAUD), poor hard copy, and the early limitations on vector graphic input capabilities. The recent acquisition of the Adage 330 Graphic Display system has greatly enhanced the potential for interactive computer aided design.
An integrated introduction to computer graphics and geometric modeling
Goldman, Ronald
2009-01-01
… this book may be the first book on geometric modelling that also covers computer graphics. In addition, it may be the first book on computer graphics that integrates a thorough introduction to 'freedom' curves and surfaces and to the mathematical foundations for computer graphics. … the book is well suited for an undergraduate course. … The entire book is very well presented and obviously written by a distinguished and creative researcher and educator. It certainly is a textbook I would recommend. …-Computer-Aided Design, 42, 2010… Many books concentrate on computer programming and soon beco
1 COMPUTER GRAPHICS AND SPECIAL EFFECTS: A CREATIVE ...
African Journals Online (AJOL)
Microsoft
2012-07-01
Jul 1, 2012 ... and „Bollywood‟ in India. ... Nollywood practitioners must tap into this very virgin area of film .... Computer Development Division, and a group of over half-dozen ... commercial computer graphics were created for television. 9.
Interactive computer graphics and its role in control system design of large space structures
Reddy, A. S. S. R.
1985-01-01
This paper attempts to show the relevance of interactive computer graphics in the design of control systems to maintain attitude and shape of large space structures to accomplish the required mission objectives. The typical phases of control system design, starting from the physical model such as modeling the dynamics, modal analysis, and control system design methodology are reviewed and the need of the interactive computer graphics is demonstrated. Typical constituent parts of large space structures such as free-free beams and free-free plates are used to demonstrate the complexity of the control system design and the effectiveness of the interactive computer graphics.
The complete guide to blender graphics computer modeling and animation
Blain, John M
2014-01-01
Smoothly Leads Users into the Subject of Computer Graphics through the Blender GUIBlender, the free and open source 3D computer modeling and animation program, allows users to create and animate models and figures in scenes, compile feature movies, and interact with the models and create video games. Reflecting the latest version of Blender, The Complete Guide to Blender Graphics: Computer Modeling & Animation, 2nd Edition helps beginners learn the basics of computer animation using this versatile graphics program. This edition incorporates many new features of Blender, including developments
Energy Technology Data Exchange (ETDEWEB)
Ota, K.; Tuchiya, H. (OYO Corp., Tokyo (Japan))
1994-05-01
In relation to how to visualize the underground, the present report introduces computer graphic (CG) devices easily usable by site technicians. Examples of utilizing them are also explained. A printer connected to the personal computer or EWS by interface is outlined together with the operational principle of printer and plotter, and points to which attention must be paid for structuring them as a system. Also, exhibited is an imaging system connected to the minicomputer or EWS. Then, an example of indicating, with an accentuation by CG expression, the characteristics of underground radar survey data is introduced together with another one of outputting, by two types of plotter, the seabed surface survey data by side scan sonar. As for the geological profile preparation system by CG technology, its structure of both software and hardware is outlined together with its system function and examples of utilization giving its excellent system effect. 8 refs., 3 figs., 2 tabs.
Design for scalability in 3D computer graphics architectures
DEFF Research Database (Denmark)
Holten-Lund, Hans Erik
2002-01-01
This thesis describes useful methods and techniques for designing scalable hybrid parallel rendering architectures for 3D computer graphics. Various techniques for utilizing parallelism in a pipelines system are analyzed. During the Ph.D study a prototype 3D graphics architecture named Hybris has...... been developed. Hybris is a prototype rendering architeture which can be tailored to many specific 3D graphics applications and implemented in various ways. Parallel software implementations for both single and multi-processor Windows 2000 system have been demonstrated. Working hardware...... as a case study and an application of the Hybris graphics architecture....
High-performance dynamic quantum clustering on graphics processors
Energy Technology Data Exchange (ETDEWEB)
Wittek, Peter, E-mail: peterwittek@acm.org [Swedish School of Library and Information Science, University of Boras, Boras (Sweden)
2013-01-15
Clustering methods in machine learning may benefit from borrowing metaphors from physics. Dynamic quantum clustering associates a Gaussian wave packet with the multidimensional data points and regards them as eigenfunctions of the Schroedinger equation. The clustering structure emerges by letting the system evolve and the visual nature of the algorithm has been shown to be useful in a range of applications. Furthermore, the method only uses matrix operations, which readily lend themselves to parallelization. In this paper, we develop an implementation on graphics hardware and investigate how this approach can accelerate the computations. We achieve a speedup of up to two magnitudes over a multicore CPU implementation, which proves that quantum-like methods and acceleration by graphics processing units have a great relevance to machine learning.
USE OF INFORMATION TECHNOLOGIES IN TEACHING COMPUTER GRAPHICS
Directory of Open Access Journals (Sweden)
Tel'noy Viktor Ivanovich
2012-10-01
Full Text Available Peculiarities of teaching computer graphics as part of the course of engineering graphics aimed at the mastering of AutoCAD graphic editor are considered by the authors. The objective of the course is to develop the competencies of future professionals, inlcuding their structural design skills. The authors recommend incorporation of mini-lectures and computer workshops into the training process. Computer quizzes are to be held at the beginning of each class to consolidate the material, to ensure preparedness for mastering new information and to stimulate the process of learning. Department of descriptive geometry and engineering graphics developed a special methodology to ensure efficient presentation of theoretical material that incorporates special computer techniques and an original structure and succession of computer slides to improve the information intensity of the computer graphics course that enjoys a small number of lecturing hours allocated within training programmes offered by the University. Well-balanced tests to be performed by students in the course of their computer workshops facilitate their mastering computer graphics techniques that help them make high-quality error-free working drawings.
Molecular Dynamics Simulation of Macromolecules Using Graphics Processing Unit
Xu, Ji; Ge, Wei; Yu, Xiang; Yang, Xiaozhen; Li, Jinghai
2010-01-01
Molecular dynamics (MD) simulation is a powerful computational tool to study the behavior of macromolecular systems. But many simulations of this field are limited in spatial or temporal scale by the available computational resource. In recent years, graphics processing unit (GPU) provides unprecedented computational power for scientific applications. Many MD algorithms suit with the multithread nature of GPU. In this paper, MD algorithms for macromolecular systems that run entirely on GPU are presented. Compared to the MD simulation with free software GROMACS on a single CPU core, our codes achieve about 10 times speed-up on a single GPU. For validation, we have performed MD simulations of polymer crystallization on GPU, and the results observed perfectly agree with computations on CPU. Therefore, our single GPU codes have already provided an inexpensive alternative for macromolecular simulations on traditional CPU clusters and they can also be used as a basis to develop parallel GPU programs to further spee...
Use of Interactive Computer Graphics to Solve Routing Problems.
Gillett, B. E.; Lawrence, J. L.
1981-01-01
Discusses vehicle routing problems and solutions. Describes testing of an interactive computer graphics package combining several types of solutions that allows users with little or no experience to work out routing problems. (Author/RW)
Application of Computer Graphics to Performance Studies of Missile Warheads
Directory of Open Access Journals (Sweden)
K. Rama Rao
1991-01-01
Full Text Available Intercept geometry of target aircraft and missiles play an important role in determining the effectiveness of the warhead. Factors such as fragment spatial distribution profile, damage capabilities, target and missile characteristics have been considered and visualised through computer graphics and optimum intercept intercept angles have been arrived. Computer graphics has proved to be an important tool to enhance perception and conceptual design capabilities in the design environment.
Hidalgo, R.C.; Kanzaki, T.; Alonso-Marroquin, F.; Luding, S.; Yu, A.; Dong, K.; Yang, R.; Luding, S.
2013-01-01
General-purpose computation on Graphics Processing Units (GPU) on personal computers has recently become an attractive alternative to parallel computing on clusters and supercomputers. We present the GPU-implementation of an accurate molecular dynamics algorithm for a system of spheres. The new hybr
Release and Dynamic Management of CAD Network Graphics Library
Institute of Scientific and Technical Information of China (English)
XU Mao-feng; ZHANG Yi; LIU Fang; LI Ai-jun
2003-01-01
We aimed at the release and dynamic management of CAD network graphics library (NGL). The characteristics of realization on network of CAD graphics are analysed, while the existing problems of the presenting share methods of graphics file are also discussed. Release and dynamic management are accomplished with the B/S combined with C/S as well as the file organization based on attribute information, which have essential practical sense to the establishment of CAD NGL, share and cooperation in tech-design as well as the distance education of engineering graphics.
Individual Stochastic Screening for the Development of Computer Graphics
Directory of Open Access Journals (Sweden)
Maja Turcic
2011-12-01
Full Text Available With the emergence of new tools and media, art and design have developed into digital computer-generated works. This article presents a sequence of creating art graphics because their original authors have not published the procedures. The goal is to discover the mathematics of an image and the programming libretto with the purpose of organizing a structural base of computer graphics. We will elaborate the procedures used to produce graphics known throughout the history of art, but that are nowadays also found in design and security graphics. The results are closely related graphics obtained by changing parameters that initiate them. The aim is to control the graphics, i.e. to use controlled stochastic to achieve desired solutions. Since the artists from the past have never published the procedures of screening methods, their ideas have remained “only” the works of art. In this article we will present the development of the algorithm that, more or less successfully, simulates those screening solutions. It has been proven that mathematically defined graphical elements serve as screening elements. New technological and mathematical solutions are introduced in the reproduction with individual screening elements to be used in printing.
Individual Stochastic Screening for the Development of Computer Graphics
Directory of Open Access Journals (Sweden)
Maja Turčić¹*
2012-12-01
Full Text Available With the emergence of new tools and media, art and design have developed into digital computer-generated works. This article presents a sequence of creating art graphics because their original authors have not published the procedures. The goal is to discover the mathematics of an image and the programming libretto with the purpose of organizing a structural base of computer graphics. We will elaborate the procedures used to produce graphics known throughout the history of art, but that are nowadays also found in design and security graphics. The results are closely related graphics obtained by changing parameters that initiate them. The aim is to control the graphics, i.e. to use controlled stochastic to achieve desired solutions. Since the artists from the past have never published the procedures of screening methods, their ideas have remained “only” the works of art. In this article we will present the development of the algorithm that, more or less successfully, simulates those screening solutions. It has been proven that mathematically defined graphical elements serve as screening elements. New technological and mathematical solutions are introduced in the reproduction with individual screening elements to be used in printing.
Integration of rocket turbine design and analysis through computer graphics
Hsu, Wayne; Boynton, Jim
1988-01-01
An interactive approach with engineering computer graphics is used to integrate the design and analysis processes of a rocket engine turbine into a progressive and iterative design procedure. The processes are interconnected through pre- and postprocessors. The graphics are used to generate the blade profiles, their stacking, finite element generation, and analysis presentation through color graphics. Steps of the design process discussed include pitch-line design, axisymmetric hub-to-tip meridional design, and quasi-three-dimensional analysis. The viscous two- and three-dimensional analysis codes are executed after acceptable designs are achieved and estimates of initial losses are confirmed.
Retrospective Study on Mathematical Modeling Based on Computer Graphic Processing
Zhang, Kai Li
Graphics & image making is an important field in computer application, in which visualization software has been widely used with the characteristics of convenience and quick. However, it was thought by modeling designers that the software had been limited in it's function and flexibility because mathematics modeling platform was not built. A non-visualization graphics software appearing at this moment enabled the graphics & image design has a very good mathematics modeling platform. In the paper, a polished pyramid is established by multivariate spline function algorithm, and validate the non-visualization software is good in mathematical modeling.
Essentials of interactive computer graphics concepts and implementation
Sung, Kelvin; Baer, Steven
2008-01-01
This undergraduate-level computer graphics text provides the reader with conceptual and practical insights into how to approach building a majority of the interactive graphics applications they encounter daily. As each topic is introduced, students are guided in developing a software library that will support fast prototyping of moderately complex applications using a variety of APIs, including OpenGL and DirectX.
Iconographic dental typography. A dental character font for computer graphics.
McCormack, J
1991-06-08
The recent massive increase in available memory for microcomputers now allows multiple font faces to be stored in computer RAM memory for instant access to the screen and for printed output. Fonts can be constructed in which the characters are not just letters or numbers, but are miniature graphic icons--in this instance pictures of teeth. When printed on an appropriate laser printer, this produces printed graphics of publishing quality.
Graphics and composite material computer program enhancements for SPAR
Farley, G. L.; Baker, D. J.
1980-01-01
User documentation is provided for additional computer programs developed for use in conjunction with SPAR. These programs plot digital data, simplify input for composite material section properties, and compute lamina stresses and strains. Sample problems are presented including execution procedures, program input, and graphical output.
DACIA LOGAN LIVE AXLE OPTIMISATION USING COMPUTER GRAPHICS
Directory of Open Access Journals (Sweden)
KIRALY Andrei
2017-05-01
Full Text Available The paper presents some contributions to the calculus and optimisation of a live axle used at Dacia Logan using computer graphics software for creating the model and afterwards using FEA evaluation to determine the effectiveness of the optimisation. Thus using specialized computer software, a simulation is made and the results were compared to the measured real prototype.
Computer Art--A New Tool in Advertising Graphics.
Wassmuth, Birgit L.
Using computers to produce art began with scientists, mathematicians, and individuals with strong technical backgrounds who used the graphic material as visualizations of data in technical fields. People are using computer art in advertising, as well as in painting; sculpture; music; textile, product, industrial, and interior design; architecture;…
The Use of Computer Graphics in the Design Process.
Palazzi, Maria
This master's thesis examines applications of computer technology to the field of industrial design and ways in which technology can transform the traditional process. Following a statement of the problem, the history and applications of the fields of computer graphics and industrial design are reviewed. The traditional industrial design process…
Computer Art--A New Tool in Advertising Graphics.
Wassmuth, Birgit L.
Using computers to produce art began with scientists, mathematicians, and individuals with strong technical backgrounds who used the graphic material as visualizations of data in technical fields. People are using computer art in advertising, as well as in painting; sculpture; music; textile, product, industrial, and interior design; architecture;…
Computer graphic of LHC in the tunnel
1996-01-01
A computer-generated image of the LHC particle accelerator at CERN in the tunnel originally built for the LEP accelerator that was closed in 2000. The cross-section of an LHC superconducting dipole magnet is also seen.
Animation graphic interface for the space shuttle onboard computer
Wike, Jeffrey; Griffith, Paul
1989-01-01
Graphics interfaces designed to operate on space qualified hardware challenge software designers to display complex information under processing power and physical size constraints. Under contract to Johnson Space Center, MICROEXPERT Systems is currently constructing an intelligent interface for the LASER DOCKING SENSOR (LDS) flight experiment. Part of this interface is a graphic animation display for Rendezvous and Proximity Operations. The displays have been designed in consultation with Shuttle astronauts. The displays show multiple views of a satellite relative to the shuttle, coupled with numeric attitude information. The graphics are generated using position data received by the Shuttle Payload and General Support Computer (PGSC) from the Laser Docking Sensor. Some of the design considerations include crew member preferences in graphic data representation, single versus multiple window displays, mission tailoring of graphic displays, realistic 3D images versus generic icon representations of real objects, the physical relationship of the observers to the graphic display, how numeric or textual information should interface with graphic data, in what frame of reference objects should be portrayed, recognizing conditions of display information-overload, and screen format and placement consistency.
Energy Technology Data Exchange (ETDEWEB)
Tsuruno, Reiji; Matsui, Nobuyuki; Bamba, Eiichi
1988-09-01
Recently there are a lot of reports of 3-Dimensional Medical Imaging from CT (Computed Tomography) using Computer Graphics technology. By the way, the greater part of them use Semi-Transparent or cutout-display algorhythm to display 3D images of objects is human body. But these algorhythm can not display figure so clearly that operater can recognize location of target and around organisms at same time. But it is necessary in medical use computer graphics. This paper reports an animation-method in order to display cerebral tumor in human brain. This animation plays a set of multiplex cutout-display frames. The cutout-display exceeds to present inside data only on cutout plain. So, many cutout-display images can present many inside data. Animation is one of effective method to display a lot of frames. And automatic or manual-operation playback of animation made it to be able to present inner structure effectively.
Computer Graphics for System Effectiveness Analysis.
1986-05-01
02139, August 1982. Chapra , Steven C., and Raymond P. Canale, (1985), Numerical Methods for Engineers with Personal Computer Applications New York...I -~1.2 Outline of Thesis .................................. 1..... .......... CHAPTER 11. METHOD OF ANALYSIS...Chapter VII summarizes the results and gives recommendations for future research. I - P** METHOD OF ANALYSIS 2.1 Introduction Systems effectiveness
3D Computer Graphics and Nautical Charts
Porathe, Thomas
2011-01-01
This paper gives an overview of an ongoing project using real-time 3D visualization to display nautical charts in a way used by 3D computer games. By displaying the map in an egocentric perspective the need to make cognitively demanding mental rotations are suggested to be removed, leading to faster decision-making and less errors. Experimental results support this hypothesis. Practical tests with limited success have been performed this year.
A remote computer graphics user at General Motors
Murphy, H. S.
1982-01-01
The successful use of automotive body surface design data is described. This data has been originally created elsewhere in GM's two large computer graphics systems of CADANCE and Fisher Graphics. As a supplier exterior lighting components, radiator grilles, energy absorbing soft faced bumper systems, and other associated items, Guide has become most dependent on the corporate computer graphics systems to supply accurate car body styling and sheet metal surfacing information for the design of their products. The presentation includes the origin and transfer of design data to a remote user site; its use in the design of their products; and the ultimate production of detailed drawings, N/C punched tapes, and subsequent downstream transfers of detailed part data to a turnkey system for tool design purposes.
Dynamic Decision Making for Graphical Models Applied to Oil Exploration
Martinelli, Gabriele; Hauge, Ragnar
2012-01-01
We present a framework for sequential decision making in problems described by graphical models. The setting is given by dependent discrete random variables with associated costs or revenues. In our examples, the dependent variables are the potential outcomes (oil, gas or dry) when drilling a petroleum well. The goal is to develop an optimal selection strategy that incorporates a chosen utility function within an approximated dynamic programming scheme. We propose and compare different approximations, from simple heuristics to more complex iterative schemes, and we discuss their computational properties. We apply our strategies to oil exploration over multiple prospects modeled by a directed acyclic graph, and to a reservoir drilling decision problem modeled by a Markov random field. The results show that the suggested strategies clearly improve the simpler intuitive constructions, and this is useful when selecting exploration policies.
Software-based geometry operations for 3D computer graphics
Sima, M.; Iancu, D.; Glossner, J.; Schulte, M.; Mamidi, S.
2006-01-01
In order to support a broad dynamic range and a high degree of precision, many of 3D renderings fundamental algorithms have been traditionally performed in floating-point. However, fixed-point data representation is preferable over floatingpoint representation in graphics applications on embedded de
Software-based geometry operations for 3D computer graphics
Sima, M.; Iancu, D.; Glossner, J.; Schulte, M.; Mamidi, S.
2006-01-01
In order to support a broad dynamic range and a high degree of precision, many of 3D renderings fundamental algorithms have been traditionally performed in floating-point. However, fixed-point data representation is preferable over floatingpoint representation in graphics applications on embedded
Visualization of Minkowski operations by computer graphics techniques
Roerdink, J.B.T.M.; Blaauwgeers, G.S.M.; Serra, J; Soille, P
1994-01-01
We consider the problem of visualizing 3D objects defined as a Minkowski addition or subtraction of elementary objects. It is shown that such visualizations can be obtained by using techniques from computer graphics such as ray tracing and Constructive Solid Geometry. Applications of the method are
Application of computer graphics for assessment of spinal deformities.
Vandegriend, B; Hill, D; Raso, J; Durdle, N; Zhang, Z
1995-03-01
A graphical portrayal system to assess spinal deformities is described. The system is based on software to display and manipulate three-dimensional images of the spine and trunk surface. Qualitative measurements of internal spinal alignment and trunk appearance are provided. The graphics display is developed using graPHIGS routines in conjunction with the C programming language and the UNIX operating system. This software provides clinicians with a computer-aided measurement tool that rapidly conveys clear and concise information about the deformities associated with abnormal spinal curvatures.
Use of computer graphics simulation for teaching of flexible sigmoidoscopy.
Baillie, J; Jowell, P; Evangelou, H; Bickel, W; Cotton, P
1991-05-01
The concept of simulation training in endoscopy is now well-established. The systems currently under development employ either computer graphics simulation or interactive video technology; each has its strengths and weaknesses. A flexible sigmoidoscopy training device has been designed which uses graphic routines--such as object oriented programming and double buffering--in entirely new ways. These programming techniques compensate for the limitations of currently available desk-top microcomputers. By boosting existing computer 'horsepower' with next generation coprocessors and sophisticated graphics tools such as intensity interpolation (Gouraud shading), the realism of computer simulation of flexible sigmoidoscopy is being greatly enhanced. The computer program has teaching and scoring capabilities, making it a truly interactive system. Use has been made of this ability to record, grade and store each trainee encounter in computer memory as part of a multi-center, prospective trial of simulation training being conducted currently in the USA. A new input device, a dummy endoscope, has been designed that allows application of variable resistance to the insertion tube. This greatly enhances tactile feedback, such as resistance during looping. If carefully designed trials show that computer simulation is an attractive and effective training tool, it is expected that this technology will evolve rapidly and be made widely available to trainee endoscopists.
Integrated Graphics Operations and Analysis Lab Development of Advanced Computer Graphics Algorithms
Wheaton, Ira M.
2011-01-01
The focus of this project is to aid the IGOAL in researching and implementing algorithms for advanced computer graphics. First, this project focused on porting the current International Space Station (ISS) Xbox experience to the web. Previously, the ISS interior fly-around education and outreach experience only ran on an Xbox 360. One of the desires was to take this experience and make it into something that can be put on NASA s educational site for anyone to be able to access. The current code works in the Unity game engine which does have cross platform capability but is not 100% compatible. The tasks for an intern to complete this portion consisted of gaining familiarity with Unity and the current ISS Xbox code, porting the Xbox code to the web as is, and modifying the code to work well as a web application. In addition, a procedurally generated cloud algorithm will be developed. Currently, the clouds used in AGEA animations and the Xbox experiences are a texture map. The desire is to create a procedurally generated cloud algorithm to provide dynamically generated clouds for both AGEA animations and the Xbox experiences. This task consists of gaining familiarity with AGEA and the plug-in interface, developing the algorithm, creating an AGEA plug-in to implement the algorithm inside AGEA, and creating a Unity script to implement the algorithm for the Xbox. This portion of the project was unable to be completed in the time frame of the internship; however, the IGOAL will continue to work on it in the future.
PHOTOREALISTIC COMPUTER GRAPHICS FORENSICS BASED ON LEADING DIGIT LAW
Institute of Scientific and Technical Information of China (English)
Xu Bo; Wang Junwen; Liu Guangjie; Dai Yuewei
2011-01-01
As the advent and growing popularity of image rendering software,photorealistic computer graphics are becoming more and more perceptually indistinguishable from photographic images.If the faked images are abused,it may lead to potential social,legal or private consequences.To this end,it is very necessary and also challenging to find effective methods to differentiate between them.In this paper,a novel leading digit law,also called Benford's law,based method to identify computer graphics is proposed.More specifically,statistics of the most significant digits are extracted from image's Discrete Cosine Transform (DCT) coefficients and magnitudes of image's gradient,and then the Support Vector Machine (SVM) based classifiers are built.Results of experiments on the image datasets indicate that the proposed method is comparable to prior works.Besides,it possesses low dimensional features and low computational complexity.
Directory of Open Access Journals (Sweden)
Rubén Ledesma
2002-12-01
Full Text Available En este trabajo se presenta una herramienta informática original que permite realizar análisis de consistencia interna (modelo Alfa de Cronbach utilizando métodos gráficos dinámicos. Se trata de un módulo basado en la filosofía del Análisis Exploratorio de Datos y en métodos de visualización estadística, diseñado para asistir al analista en el proceso de construcción de pruebas psicológicas. La herramienta permite analizar la consistencia interna de la prueba, las propiedades de los ítems que la componen, los patrones de respuesta de los sujetos a los ítems, y el efecto de la eliminación de los ítems y del incremento en la longitud de la prueba sobre su fiabilidad. En comparación con otros programas existentes, el beneficio del módulo es la incorporación de gráficos estadísticos dinámicos como complemento a la presentación de resultados convencionales en formato texto.This paper describes a computer software that provides dynamic graphics to perform internal consistence analysis by means of Cronbach’s Alpha. This software, based on Exploratory Data Analysis philosophy and statistical visualization methods, is designed to assist the process of psychological test and scale construction. It allows carry out internal consistency analysis, as well as exploring statistical properties of items, subject responses patterns, and the effect of item deletion and test length increase on reliability coefficient. Comparing with other statistical software, the benefit of this program is to use dynamic graphics complementing statistical output.
Computing trends using graphic processor in high energy physics
Niculescu, Mihai
2011-01-01
One of the main challenges in Heavy Energy Physics is to make fast analysis of high amount of experimental and simulated data. At LHC-CERN one p-p event is approximate 1 Mb in size. The time taken to analyze the data and obtain fast results depends on high computational power. The main advantage of using GPU(Graphic Processor Unit) programming over traditional CPU one is that graphical cards bring a lot of computing power at a very low price. Today a huge number of application(scientific, financial etc) began to be ported or developed for GPU, including Monte Carlo tools or data analysis tools for High Energy Physics. In this paper, we'll present current status and trends in HEP using GPU.
Exploiting graphics processing units for computational biology and bioinformatics.
Payne, Joshua L; Sinnott-Armstrong, Nicholas A; Moore, Jason H
2010-09-01
Advances in the video gaming industry have led to the production of low-cost, high-performance graphics processing units (GPUs) that possess more memory bandwidth and computational capability than central processing units (CPUs), the standard workhorses of scientific computing. With the recent release of generalpurpose GPUs and NVIDIA's GPU programming language, CUDA, graphics engines are being adopted widely in scientific computing applications, particularly in the fields of computational biology and bioinformatics. The goal of this article is to concisely present an introduction to GPU hardware and programming, aimed at the computational biologist or bioinformaticist. To this end, we discuss the primary differences between GPU and CPU architecture, introduce the basics of the CUDA programming language, and discuss important CUDA programming practices, such as the proper use of coalesced reads, data types, and memory hierarchies. We highlight each of these topics in the context of computing the all-pairs distance between instances in a dataset, a common procedure in numerous disciplines of scientific computing. We conclude with a runtime analysis of the GPU and CPU implementations of the all-pairs distance calculation. We show our final GPU implementation to outperform the CPU implementation by a factor of 1700.
PLM-COMPETENCE FORMATION USING COMPUTATIONAL-GRAPHICAL PRACTICE
Directory of Open Access Journals (Sweden)
Vladimir V. Zelentsov
2014-01-01
Full Text Available The description of a new kind of learning activity “Computational - graphical practice” is presented. This practice aimed at consolidating the knowledge and skills acquired by students in the study of the basic engineering disciplines and bridge the gap in the training of students in the field of PLM-technology. The goals, objectives, program practices and competencies, which should have a student after passing the training practice, are listed
Using Virtual Environments in the Teaching of Computer Graphics
Bowman, Doug A.; Chennupati, Balaprasuna; Gracey, Matthew; Pinho, Marcio S.; Wheeler, Kristin J.
2003-01-01
Education has long been touted as an appropriate application area for immersive virtual environments (VEs), but few immersive applications have actually been used in the classroom, and even fewer have been compared empirically with other teaching methods. This paper presents VENTS, a novel immersive VE application intended to teach the concept of the three-dimensional (3D) normalizing transformation in an undergraduate computer graphics class. VENTS was developed based...
Factorial graphical lasso for dynamic networks
Wit, E. C.; Abbruzzo, A.
2012-01-01
Dynamic networks models describe a growing number of important scientific processes, from cell biology and epidemiology to sociology and finance. There are many aspects of dynamical networks that require statistical considerations. In this paper we focus on determining network structure. Estimating
Future Trends in Computer Graphics: How Much is Enough?
Institute of Scientific and Technical Information of China (English)
A.R.Forrest
2003-01-01
Over the forty-year history of interactive computer graphics, there have been con-tinuous advances, but at some stage this progression must terminate with images being sufficientlyrealistic for all practical purposes. How much detail do we really need? Polygon counts over a fewmillion imply that on average each polygon paints less than a single pixel, making use of polygonshading hardware wasteful. We consider the problem of determining how much realism is requiredfor a variety of applications. We discuss how current trends in computer graphics hardware, and inparticular of graphics cards targeted at the computer games industry, will help or hinder achieve-ment of these requirements. With images now being so convincingly realistic in many cases, criticalfaculties are often suspended and the images are accepted as correct and truthful although theymay well be incorrect and sometimes misleading or untruthful. Display resolution has remainedlargely constant in spatial terms for the last twenty years and in terms of the number of pixelshas increased by less than an order of magnitude. If the long-promised breakthroughs in displaytechnology are finally realised, how should we use the increased resolution?
Advanced computer graphic techniques for laser range finder (LRF) simulation
Bedkowski, Janusz; Jankowski, Stanislaw
2008-11-01
This paper show an advanced computer graphic techniques for laser range finder (LRF) simulation. The LRF is the common sensor for unmanned ground vehicle, autonomous mobile robot and security applications. The cost of the measurement system is extremely high, therefore the simulation tool is designed. The simulation gives an opportunity to execute algorithm such as the obstacle avoidance[1], slam for robot localization[2], detection of vegetation and water obstacles in surroundings of the robot chassis[3], LRF measurement in crowd of people[1]. The Axis Aligned Bounding Box (AABB) and alternative technique based on CUDA (NVIDIA Compute Unified Device Architecture) is presented.
Form in the Natural Environment: Fractal Computer Graphics and Wassily Kandinsky.
Geake, John; Porter, Jim
1992-01-01
Reports on study of use of fractal geometry in a computer graphics program to improve the perception of intermediate grade level students in their paintings. Finds that students are more likely to use changing shapes and colors after viewing slides of fractal computer graphics. Concludes that fractal computer graphics would make highly engaging…
Cichero, Elena; D'Ursi, Pasqualina; Moscatelli, Marco; Bruno, Olga; Orro, Alessandro; Rotolo, Chiara; Milanesi, Luciano; Fossa, Paola
2013-12-01
Phosphodiesterase 11 (PDE11) is the latest isoform of the PDEs family to be identified, acting on both cyclic adenosine monophosphate and cyclic guanosine monophosphate. The initial reports of PDE11 found evidence for PDE11 expression in skeletal muscle, prostate, testis, and salivary glands; however, the tissue distribution of PDE11 still remains a topic of active study and some controversy. Given the sequence similarity between PDE11 and PDE5, several PDE5 inhibitors have been shown to cross-react with PDE11. Accordingly, many non-selective inhibitors, such as IBMX, zaprinast, sildenafil, and dipyridamole, have been documented to inhibit PDE11. Only recently, a series of dihydrothieno[3,2-d]pyrimidin-4(3H)-one derivatives proved to be selective toward the PDE11 isoform. In the absence of experimental data about PDE11 X-ray structures, we found interesting to gain a better understanding of the enzyme-inhibitor interactions using in silico simulations. In this work, we describe a computational approach based on homology modeling, docking, and molecular dynamics simulation to derive a predictive 3D model of PDE11. Using a Graphical Processing Unit architecture, it is possible to perform long simulations, find stable interactions involved in the complex, and finally to suggest guideline for the identification and synthesis of potent and selective inhibitors.
Neurosurgical simulation by interactive computer graphics on iPad.
Maruyama, Keisuke; Kin, Taichi; Saito, Toki; Suematsu, Shinya; Gomyo, Miho; Noguchi, Akio; Nagane, Motoo; Shiokawa, Yoshiaki
2014-11-01
Presurgical simulation before complicated neurosurgery is a state-of-the-art technique, and its usefulness has recently become well known. However, simulation requires complex image processing, which hinders its widespread application. We explored handling the results of interactive computer graphics on the iPad tablet, which can easily be controlled anywhere. Data from preneurosurgical simulations from 12 patients (4 men, 8 women) who underwent complex brain surgery were loaded onto an iPad. First, DICOM data were loaded using Amira visualization software to create interactive computer graphics, and ParaView, another free visualization software package, was used to convert the results of the simulation to be loaded using the free iPad software KiwiViewer. The interactive computer graphics created prior to neurosurgery were successfully displayed and smoothly controlled on the iPad in all patients. The number of elements ranged from 3 to 13 (mean 7). The mean original data size was 233 MB, which was reduced to 10.4 MB (4.4% of original size) after image processing by ParaView. This was increased to 46.6 MB (19.9%) after decompression in KiwiViewer. Controlling the magnification, transfer, rotation, and selection of translucence in 10 levels of each element were smoothly and easily performed using one or two fingers. The requisite skill to smoothly control the iPad software was acquired within 1.8 trials on average in 12 medical students and 6 neurosurgical residents. Using an iPad to handle the result of preneurosurgical simulation was extremely useful because it could easily be handled anywhere.
Some methods of computational geometry applied to computer graphics
Overmars, M.H.; Edelsbrunner, H.; Seidel, R.
1984-01-01
Abstract Windowing a two-dimensional picture means to determine those line segments of the picture that are visible through an axis-parallel window. A study of some algorithmic problems involved in windowing a picture is offered. Some methods from computational geometry are exploited to store the
Color calculations for and perceptual assessment of computer graphic images
Energy Technology Data Exchange (ETDEWEB)
Meyer, G.W.
1986-01-01
Realistic image synthesis involves the modelling of an environment in accordance with the laws of physics and the production of a final simulation that is perceptually acceptable. To be considered a scientific endeavor, synthetic image generation should also include the final step of experimental verification. This thesis concentrates on the color calculations that are inherent in the production of the final simulation and on the perceptual assessment of the computer graphic images that result. The fundamental spectral sensitivity functions that are active in the human visual system are introduced and are used to address color-blindness issues in computer graphics. A digitally controlled color television monitor is employed to successfully implement both the Farnsworth Munsell 100 hues test and a new color vision test that yields more accurate diagnoses. Images that simulate color blind vision are synthesized and are used to evaluate color scales for data display. Gaussian quadrature is used with a set of opponent fundamental to select the wavelengths at which to perform synthetic image generation.
Solar physics applications of computer graphics and image processing
Altschuler, M. D.
1985-01-01
Computer graphics devices coupled with computers and carefully developed software provide new opportunities to achieve insight into the geometry and time evolution of scalar, vector, and tensor fields and to extract more information quickly and cheaply from the same image data. Two or more different fields which overlay in space can be calculated from the data (and the physics), then displayed from any perspective, and compared visually. The maximum regions of one field can be compared with the gradients of another. Time changing fields can also be compared. Images can be added, subtracted, transformed, noise filtered, frequency filtered, contrast enhanced, color coded, enlarged, compressed, parameterized, and histogrammed, in whole or section by section. Today it is possible to process multiple digital images to reveal spatial and temporal correlations and cross correlations. Data from different observatories taken at different times can be processed, interpolated, and transformed to a common coordinate system.
Solar physics applications of computer graphics and image processing
Altschuler, M. D.
1985-01-01
Computer graphics devices coupled with computers and carefully developed software provide new opportunities to achieve insight into the geometry and time evolution of scalar, vector, and tensor fields and to extract more information quickly and cheaply from the same image data. Two or more different fields which overlay in space can be calculated from the data (and the physics), then displayed from any perspective, and compared visually. The maximum regions of one field can be compared with the gradients of another. Time changing fields can also be compared. Images can be added, subtracted, transformed, noise filtered, frequency filtered, contrast enhanced, color coded, enlarged, compressed, parameterized, and histogrammed, in whole or section by section. Today it is possible to process multiple digital images to reveal spatial and temporal correlations and cross correlations. Data from different observatories taken at different times can be processed, interpolated, and transformed to a common coordinate system.
Engineering computer graphics in gas turbine engine design, analysis and manufacture
Lopatka, R. S.
1975-01-01
A time-sharing and computer graphics facility designed to provide effective interactive tools to a large number of engineering users with varied requirements was described. The application of computer graphics displays at several levels of hardware complexity and capability is discussed, with examples of graphics systems tracing gas turbine product development, beginning with preliminary design through manufacture. Highlights of an operating system stylized for interactive engineering graphics is described.
Three Dimensional Computer Graphics Federates for the 2012 Smackdown Simulation
Fordyce, Crystal; Govindaiah, Swetha; Muratet, Sean; O'Neil, Daniel A.; Schricker, Bradley C.
2012-01-01
The Simulation Interoperability Standards Organization (SISO) Smackdown is a two-year old annual event held at the 2012 Spring Simulation Interoperability Workshop (SIW). A primary objective of the Smackdown event is to provide college students with hands-on experience in developing distributed simulations using High Level Architecture (HLA). Participating for the second time, the University of Alabama in Huntsville (UAHuntsville) deployed four federates, two federates simulated a communications server and a lunar communications satellite with a radio. The other two federates generated 3D computer graphics displays for the communication satellite constellation and for the surface based lunar resupply mission. Using the Light-Weight Java Graphics Library, the satellite display federate presented a lunar-texture mapped sphere of the moon and four Telemetry Data Relay Satellites (TDRS), which received object attributes from the lunar communications satellite federate to drive their motion. The surface mission display federate was an enhanced version of the federate developed by ForwardSim, Inc. for the 2011 Smackdown simulation. Enhancements included a dead-reckoning algorithm and a visual indication of which communication satellite was in line of sight of Hadley Rille. This paper concentrates on these two federates by describing the functions, algorithms, HLA object attributes received from other federates, development experiences and recommendations for future, participating Smackdown teams.
Graphics processing units in bioinformatics, computational biology and systems biology.
Nobile, Marco S; Cazzaniga, Paolo; Tangherloni, Andrea; Besozzi, Daniela
2016-07-08
Several studies in Bioinformatics, Computational Biology and Systems Biology rely on the definition of physico-chemical or mathematical models of biological systems at different scales and levels of complexity, ranging from the interaction of atoms in single molecules up to genome-wide interaction networks. Traditional computational methods and software tools developed in these research fields share a common trait: they can be computationally demanding on Central Processing Units (CPUs), therefore limiting their applicability in many circumstances. To overcome this issue, general-purpose Graphics Processing Units (GPUs) are gaining an increasing attention by the scientific community, as they can considerably reduce the running time required by standard CPU-based software, and allow more intensive investigations of biological systems. In this review, we present a collection of GPU tools recently developed to perform computational analyses in life science disciplines, emphasizing the advantages and the drawbacks in the use of these parallel architectures. The complete list of GPU-powered tools here reviewed is available at http://bit.ly/gputools. © The Author 2016. Published by Oxford University Press.
The Scree Test and the Number of Factors: a Dynamic Graphics Approach.
Ledesma, Rubén Daniel; Valero-Mora, Pedro; Macbeth, Guillermo
2015-03-17
Exploratory Factor Analysis and Principal Component Analysis are two data analysis methods that are commonly used in psychological research. When applying these techniques, it is important to determine how many factors to retain. This decision is sometimes based on a visual inspection of the Scree plot. However, the Scree plot may at times be ambiguous and open to interpretation. This paper aims to explore a number of graphical and computational improvements to the Scree plot in order to make it more valid and informative. These enhancements are based on dynamic and interactive data visualization tools, and range from adding Parallel Analysis results to "linking" the Scree plot with other graphics, such as factor-loadings plots. To illustrate our proposed improvements, we introduce and describe an example based on real data on which a principal component analysis is appropriate. We hope to provide better graphical tools to help researchers determine the number of factors to retain.
Dynamic Resource Access Using Graphical Game in Asymmetric Wireless Networks
Directory of Open Access Journals (Sweden)
Fangwei Li
2013-08-01
Full Text Available In order to improve the resource utilization in asymmetric wireless networks, a novel dynamic resource access algorithm was presented. As the asymmetry of information and the locality of users' actions in distributed wireless networks, the resource access problem was expressed as a simple graphical game model. Let the graphic topology indicate the internal game structure of the realistic environment. Then the Nash equilibrium was got by minimizing the individual regret instead of the system regret. The proposed algorithm realized efficient resource access through exchanging the active information and regret in the competitive community. Theoretical analysis and simulation results show that the algorithm can converge to a suitable pure strategy Nash equilibrium point quickly with less amount of calculation, avoids conflict effectively, and improves the system capacity and power utilization especially in the condition of insufficient resources
Galatea ¬â€?An Interactive Computer Graphics System For Movie And Video Analysis
Potel, Michael J.; MacKay, Steven A.; Sayre, Richard E.
1983-03-01
Extracting quantitative information from movie film and video recordings has always been a difficult process. The Galatea motion analysis system represents an application of some powerful interactive computer graphics capabilities to this problem. A minicomputer is interfaced to a stop-motion projector, a data tablet, and real-time display equipment. An analyst views a film and uses the data tablet to track a moving position of interest. Simultaneously, a moving point is displayed in an animated computer graphics image that is synchronized with the film as it runs. Using a projection CRT and a series of mirrors, this image is superimposed on the film image on a large front screen. Thus, the graphics point lies on top of the point of interest in the film and moves with it at cine rates. All previously entered points can be displayed simultaneously in this way, which is extremely useful in checking the accuracy of the entries and in avoiding omission and duplication of points. Furthermore, the moving points can be connected into moving stick figures, so that such representations can be transcribed directly from film. There are many other tools in the system for entering outlines, measuring time intervals, and the like. The system is equivalent to "dynamic tracing paper" because it is used as though it were tracing paper that can keep up with running movie film. We have applied this system to a variety of problems in cell biology, cardiology, biomechanics, and anatomy. We have also extended the system using photogrammetric techniques to support entry of three-dimensional moving points from two (or more) films taken simultaneously from different perspective views. We are also presently constructing a second, lower-cost, microcomputer-based system for motion analysis in video, using digital graphics and video mixing to achieve the graphics overlay for any composite video source image.
Enhancing dynamic graphical analysis with the Lisp-Stat language and the ViSta statistical program.
Ledesma, Rubén; Molina, J Gabriel; Young, Forrest W
2005-11-01
Presented is a sample of computerized methods aimed at multidimensional scaling and psychometric item analysis that offer a dynamic graphical interface to execute analyses and help visualize the results. These methods show how the Lisp-Stat programming language and the ViSta statistical program can be jointly applied to develop powerful computer applications that enhance dynamic graphical analysis methods. The feasibility of this combined strategy relies on two main features: (1) The programming architecture of ViSta enables users to add new statistical methods as plug-ins, which are integrated into the program environment and can make use of all the functions already available in ViSta (e.g., data manipulation, editing, printing); and (2) the set of powerful statistical and graphical functions integrated into the Lisp-Stat programming language provides the means for developing statistical methods with dynamic graphical visualizations, which can be implemented as ViSta plug-ins.
Computational Representation of Situation Awareness with Graphical Expressions
Energy Technology Data Exchange (ETDEWEB)
Yim, Hobin; Seong, Poonghyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)
2013-05-15
Training is also frequently listed in general applications of SA evaluation. Unfortunately, almost of all methods are either subjective or qualitative, and often time consuming. Since the problems indicate, the core matter of using SA in training is the lack of well-developed or robust measurement tools. Therefore, an intuitive and easy handling SA measurement tool for NPP operators was developed based on the Petri-net and Bayesian inference. Measuring SA using Bayesian theory has been controversy, so sets of simulation training conducted by real NPP operators were video recorded for validation of the tool. There have been many attempts to understand cognitive processes in operators. Describing operator's SA is considered as one of the most plausible ways of such endeavors. Operator's cognitive activities in training can be a barometer of operator's unknown behavior in real situations. Knowing what the operator is thinking is important for better results of upcoming training. To give trainers an intuition that how well operators cope with dynamic situations, the quantitative tool to estimate SA named Corsage was proposed. Corsage gives reasonable clues why the operator behaves in a certain way by showing possible changes in a quantitative and graphical manner. Especially, a graphical comparison between referential information processing flow and operator's real information processing flow can offer trainers a detailed insight. In short, despite the incredulous opinion on measuring human cognition with probability, the result showed a positive view of applicability of Bayesian inference to SA measurement. The next step of the research will be improvement in responsiveness to 'rare but important' information.
Using computer graphics to enhance astronaut and systems safety
Brown, J. W.
1985-01-01
Computer graphics is being employed at the NASA Johnson Space Center as a tool to perform rapid, efficient and economical analyses for man-machine integration, flight operations development and systems engineering. The Operator Station Design System (OSDS), a computer-based facility featuring a highly flexible and versatile interactive software package, PLAID, is described. This unique evaluation tool, with its expanding data base of Space Shuttle elements, various payloads, experiments, crew equipment and man models, supports a multitude of technical evaluations, including spacecraft and workstation layout, definition of astronaut visual access, flight techniques development, cargo integration and crew training. As OSDS is being applied to the Space Shuttle, Orbiter payloads (including the European Space Agency's Spacelab) and future space vehicles and stations, astronaut and systems safety are being enhanced. Typical OSDS examples are presented. By performing physical and operational evaluations during early conceptual phases. supporting systems verification for flight readiness, and applying its capabilities to real-time mission support, the OSDS provides the wherewithal to satisfy a growing need of the current and future space programs for efficient, economical analyses.
Cohen-Or, Daniel; Ju, Tao; Mitra, Niloy J; Shamir, Ariel; Sorkine-Hornung, Olga; Zhang, Hao (Richard)
2015-01-01
A Sampler of Useful Computational Tools for Applied Geometry, Computer Graphics, and Image Processing shows how to use a collection of mathematical techniques to solve important problems in applied mathematics and computer science areas. The book discusses fundamental tools in analytical geometry and linear algebra. It covers a wide range of topics, from matrix decomposition to curvature analysis and principal component analysis to dimensionality reduction.Written by a team of highly respected professors, the book can be used in a one-semester, intermediate-level course in computer science. It
Some computer graphical user interfaces in radiation therapy
Institute of Scientific and Technical Information of China (English)
James C L Chow
2016-01-01
In this review, five graphical user interfaces(GUIs) used in radiation therapy practices and researches are introduced. They are:(1) the treatment time calculator, superficialx-ray treatment time calculator(SUPCALC) used in the superficial X-ray radiation therapy;(2) the monitor unit calculator, electron monitor unit calculator(EMUC) used in the electron radiation therapy;(3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy(SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy;(4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and(5) the monitor unit calculator, photon beam monitor unit calculator(PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls the
Some computer graphical user interfaces in radiation therapy.
Chow, James C L
2016-03-28
In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls
Study of journal bearing dynamics using 3-dimensional motion picture graphics
Brewe, D. E.; Sosoka, D. J.
1985-01-01
Computer generated motion pictures of three dimensional graphics are being used to analyze journal bearings under dynamically loaded conditions. The motion pictures simultaneously present the motion of the journal and the pressures predicted within the fluid film of the bearing as they evolve in time. The correct prediction of these fluid film pressures can be complicated by the development of cavitation within the fluid. The numerical model that is used predicts the formation of the cavitation bubble and its growth, downstream movement, and subsequent collapse. A complete physical picture is created in the motion picture as the journal traverses through the entire dynamic cycle.
The Aristotelian Rainbow: From Philosophy to Computer Graphics
DEFF Research Database (Denmark)
Frisvad, Jeppe Revall; Christensen, Niels Jørgen; Falster, Peter
2007-01-01
Developments in the graphics discipline called realistic image synthesis are in many ways related to the historical development of theories of light. And theories of light will probably continue to inspire the ongoing search for realism in graphics. To nurture this inspiration, we present the fir...
Principles of computer graphics theory and practice using OpenGL and Maya
Govil-Pai, Shalini
2004-01-01
Principles of Computer Graphics: Theory and Practice Using OpenGL and Maya' helps readers understand the principles of interactive computer graphics. Hands-on examples developed in OpenGL illustrate key concepts, and readers develop a professional animation, following traditional processes used in production houses.
Traditional Engineering Graphics versus Computer-Aided Drafting: A View from Academe.
Foster, Robert J.
1987-01-01
Argues for a legitimate role of manually expressed engineering graphics within engineering education as a needed support for computer-assisted drafting work. Discusses what and how students should learn as well as trends in engineering graphics education. Compares and contrasts manual and computer drafting methods. (CW)
Interplay of Computer and Paper-Based Sketching in Graphic Design
Pan, Rui; Kuo, Shih-Ping; Strobel, Johannes
2013-01-01
The purpose of this study is to investigate student designers' attitude and choices towards the use of computers and paper sketches when involved in a graphic design process. 65 computer graphic technology undergraduates participated in this research. A mixed method study with survey and in-depth interviews was applied to answer the research…
Interplay of Computer and Paper-Based Sketching in Graphic Design
Pan, Rui; Kuo, Shih-Ping; Strobel, Johannes
2013-01-01
The purpose of this study is to investigate student designers' attitude and choices towards the use of computers and paper sketches when involved in a graphic design process. 65 computer graphic technology undergraduates participated in this research. A mixed method study with survey and in-depth interviews was applied to answer the research…
The Case for Teaching Computer Graphics with WebGL: A 25-Year Perspective.
Angel, Ed
2017-01-01
OpenGL has been the standard API for teaching computer graphics. There are now multiple versions of the standard, including WebGL. which is the JavaScript implementation of OpenGL ES 2.0. The author argues that WebGL is the version best suited for an introductory course in computer graphics.
Graphics processing units accelerated semiclassical initial value representation molecular dynamics
Energy Technology Data Exchange (ETDEWEB)
Tamascelli, Dario; Dambrosio, Francesco Saverio [Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy); Conte, Riccardo [Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322 (United States); Ceotto, Michele, E-mail: michele.ceotto@unimi.it [Dipartimento di Chimica, Università degli Studi di Milano, via Golgi 19, 20133 Milano (Italy)
2014-05-07
This paper presents a Graphics Processing Units (GPUs) implementation of the Semiclassical Initial Value Representation (SC-IVR) propagator for vibrational molecular spectroscopy calculations. The time-averaging formulation of the SC-IVR for power spectrum calculations is employed. Details about the GPU implementation of the semiclassical code are provided. Four molecules with an increasing number of atoms are considered and the GPU-calculated vibrational frequencies perfectly match the benchmark values. The computational time scaling of two GPUs (NVIDIA Tesla C2075 and Kepler K20), respectively, versus two CPUs (Intel Core i5 and Intel Xeon E5-2687W) and the critical issues related to the GPU implementation are discussed. The resulting reduction in computational time and power consumption is significant and semiclassical GPU calculations are shown to be environment friendly.
Using computer graphics to design Space Station Freedom viewing
Goldsberry, Betty S.; Lippert, Buddy O.; Mckee, Sandra D.; Lewis, James L., Jr.; Mount, Francis E.
1993-01-01
Viewing requirements were identified early in the Space Station Freedom program for both direct viewing via windows and indirect viewing via cameras and closed-circuit television (CCTV). These requirements reside in NASA Program Definition and Requirements Document (PDRD), Section 3: Space Station Systems Requirements. Currently, analyses are addressing the feasibility of direct and indirect viewing. The goal of these analyses is to determine the optimum locations for the windows, cameras, and CCTV's in order to meet established requirements, to adequately support space station assembly, and to operate on-board equipment. PLAID, a three-dimensional computer graphics program developed at NASA JSC, was selected for use as the major tool in these analyses. PLAID provides the capability to simulate the assembly of the station as well as to examine operations as the station evolves. This program has been used successfully as a tool to analyze general viewing conditions for many Space Shuttle elements and can be used for virtually all Space Station components. Additionally, PLAID provides the ability to integrate an anthropometric scale-modeled human (representing a crew member) with interior and exterior architecture.
Computer Graphics Teaching Support using X3D: Extensible 3D Graphics for Web Authors
Brutzman, Don
2008-01-01
X3D is the ISO-standard scene-graph language for interactive 3D graphics on the Web. A new course is available for teaching the fundamentals of 3D graphics using Extensible 3D (X3D). Resources include a detailed textbook, an authoring tool, hundreds of example scenes, and detailed slidesets covering each chapter. The published book is commercially available, while all other course-module resources are provided online free under open-source licenses. Numerous other commercial and o...
Bakker, M.
1995-01-01
Cancels and replaces the first edition (1991). Specifies a language independent nucleus of a graphics system. For integration into a programming language, GKS is embedded in a language dependent layer obeying the particular conventions of that language. Specifies such a language dependent layer for
Takada, Naoki; Shimobaba, Tomoyoshi; Nakayama, Hirotaka; Shiraki, Atsushi; Okada, Naohisa; Oikawa, Minoru; Masuda, Nobuyuki; Ito, Tomoyoshi
2012-10-20
To overcome the computational complexity of a computer-generated hologram (CGH), we implement an optimized CGH computation in our multi-graphics processing unit cluster system. Our system can calculate a CGH of 6,400×3,072 pixels from a three-dimensional (3D) object composed of 2,048 points in 55 ms. Furthermore, in the case of a 3D object composed of 4096 points, our system is 553 times faster than a conventional central processing unit (using eight threads).
Energy Technology Data Exchange (ETDEWEB)
Peskin,A.M.; Shimamoto, Y.
1974-01-01
The topic of computer graphics serves well to illustrate that AEC affiliated scientific computing installations are well represented in the forefront of computing science activities. The participant response to the technical program was overwhelming--both in number of contributions and quality of the work described. Session I, entitled Advanced Systems, contains presentations describing systems that contain features not generally found in graphics facilities. These features can be roughly classified as extensions of standard two-dimensional monochromatic imaging to higher dimensions including color and time as well as multidimensional metrics. Session II presents seven diverse applications ranging from high energy physics to medicine. Session III describes a number of important developments in establishing facilities, techniques and enhancements in the computer graphics area. Although an attempt was made to schedule as many of these worthwhile presentations as possible, it appeared impossible to do so given the scheduling constraints of the meeting. A number of prospective presenters 'came to the rescue' by graciously withdrawing from the sessions. Some of their abstracts have been included in the Proceedings.
The Use of Computer Graphics to Teach Thermodynamic Phase Diagrams.
Naik, Chandrashekhar D.; And Others
1985-01-01
Describes an interactive graphics package which illustrates the phase behavior of binary mixtures. The package has been successfully used with graduate and undergraduate students in the chemical engineering curriculum at Cornell University. Features contributing to this success are noted. (JN)
Fast space-filling molecular graphics using dynamic partitioning among parallel processors.
Gertner, B J; Whitnell, R M; Wilson, K R
1991-09-01
We present a novel algorithm for the efficient generation of high-quality space-filling molecular graphics that is particularly appropriate for the creation of the large number of images needed in the animation of molecular dynamics. Each atom of the molecule is represented by a sphere of an appropriate radius, and the image of the sphere is constructed pixel-by-pixel using a generalization of the lighting model proposed by Porter (Comp. Graphics 1978, 12, 282). The edges of the spheres are antialiased, and intersections between spheres are handled through a simple blending algorithm that provides very smooth edges. We have implemented this algorithm on a multiprocessor computer using a procedure that dynamically repartitions the effort among the processors based on the CPU time used by each processor to create the previous image. This dynamic reallocation among processors automatically maximizes efficiency in the face of both the changing nature of the image from frame to frame and the shifting demands of the other programs running simultaneously on the same processors. We present data showing the efficiency of this multiprocessing algorithm as the number of processors is increased. The combination of the graphics and multiprocessor algorithms allows the fast generation of many high-quality images.
Computing Science and Statistics: Volume 24. Graphics and Visualization
1993-03-20
visited one hardware and one software linear trend in response time as a function of file size. vendor (who had several different brands of hardware...Marcus, A., (1990). Human in real-time using high-interaction graphical Factors and Typography for More Readable techniques. The display is mouse sensitive...of the New Jersey 11 Edward Tuf e (1991). Envisioning Information. Department of Health. The use of brand names in this Graphics Press, Box 43
Yamaguchi, Takuma; Ichimura, Tsuyoshi; Yagi, Yuji; Agata, Ryoichiro; Hori, Takane; Hori, Muneo
2017-08-01
As high-resolution observational data become more common, the demand for numerical simulations of crustal deformation using 3-D high-fidelity modelling is increasing. To increase the efficiency of performing numerical simulations with high computation costs, we developed a fast solver using heterogeneous computing, with graphics processing units (GPUs) and central processing units, and then used the solver in crustal deformation computations. The solver was based on an iterative solver and was devised so that a large proportion of the computation was calculated more quickly using GPUs. To confirm the utility of the proposed solver, we demonstrated a numerical simulation of the coseismic slip distribution estimation, which requires 360 000 crustal deformation computations with 82 196 106 degrees of freedom.
Telenius, Jelena; Vattulainen, Ilpo; Monticelli, Luca
2009-01-01
Computer simulation has become an increasingly popular tool in the study of lipid membranes, complementing experimental techniques by providing information on structure and dynamics at high spatial and temporal resolution. Molecular visualization is the most powerful way to represent the results of molecular simulations, and can be used to illustrate complex transformations of lipid aggregates more easily and more effectively than written text. In this chapter, we review some basic aspects of simulation methodologies commonly employed in the study of lipid membranes and we describe a few examples of complex phenomena that have been recently investigated using molecular simulations. We then explain how molecular visualization provides added value to computational work in the field of biological membranes, and we conclude by listing a few molecular graphics packages widely used in scientific publications.
An application of interactive computer graphics technology to the design of dispersal mechanisms
Richter, B. J.; Welch, B. H.
1977-01-01
Interactive computer graphics technology is combined with a general purpose mechanisms computer code to study the operational behavior of three guided bomb dispersal mechanism designs. These studies illustrate the use of computer graphics techniques to discover operational anomalies, to assess the effectiveness of design improvements, to reduce the time and cost of the modeling effort, and to provide the mechanism designer with a visual understanding of the physical operation of such systems.
A study of computer graphics technology in application of communication resource management
Li, Jing; Zhou, Liang; Yang, Fei
2017-08-01
With the development of computer technology, computer graphics technology has been widely used. Especially, the success of object-oriented technology and multimedia technology promotes the development of graphics technology in the computer software system. Therefore, the computer graphics theory and application technology have become an important topic in the field of computer, while the computer graphics technology becomes more and more extensive in various fields of application. In recent years, with the development of social economy, especially the rapid development of information technology, the traditional way of communication resource management cannot effectively meet the needs of resource management. In this case, the current communication resource management is still using the original management tools and management methods, resource management equipment management and maintenance, which brought a lot of problems. It is very difficult for non-professionals to understand the equipment and the situation in communication resource management. Resource utilization is relatively low, and managers cannot quickly and accurately understand the resource conditions. Aimed at the above problems, this paper proposes to introduce computer graphics technology into the communication resource management. The introduction of computer graphics not only makes communication resource management more vivid, but also reduces the cost of resource management and improves work efficiency.
Blazek, Jiri
2015-01-01
Computational Fluid Dynamics: Principles and Applications, Third Edition presents students, engineers, and scientists with all they need to gain a solid understanding of the numerical methods and principles underlying modern computation techniques in fluid dynamics. By providing complete coverage of the essential knowledge required in order to write codes or understand commercial codes, the book gives the reader an overview of fundamentals and solution strategies in the early chapters before moving on to cover the details of different solution techniques. This updated edition includes new
Gas Dynamics Equations: Computation
Chen, Gui-Qiang G
2012-01-01
Shock waves, vorticity waves, and entropy waves are fundamental discontinuity waves in nature and arise in supersonic or transonic gas flow, or from a very sudden release (explosion) of chemical, nuclear, electrical, radiation, or mechanical energy in a limited space. Tracking these discontinuities and their interactions, especially when and where new waves arise and interact in the motion of gases, is one of the main motivations for numerical computation for the gas dynamics equations. In this paper, we discuss some historic and recent developments, as well as mathematical challenges, in designing and formulating efficient numerical methods and algorithms to compute weak entropy solutions for the Euler equations for gas dynamics.
A 1.5 GFLOPS Reciprocal Unit for Computer Graphics
DEFF Research Database (Denmark)
Nannarelli, Alberto; Rasmussen, Morten Sleth; Stuart, Matthias Bo
2006-01-01
The reciprocal operation 1/d is a frequent operation performed in graphics processors (GPUs). In this work, we present the design of a radix-16 reciprocal unit based on the algorithm combining the traditional digit-by-digit algorithm and the approximation of the reciprocal by one Newton...
Kirk, David Blair
This thesis develops an engineering practice and design methodology to enable us to use CMOS analog VLSI chips to perform more accurate and precise computation. These techniques form the basis of an approach that permits us to build computer graphics and neural network applications using analog VLSI. The nature of the design methodology focuses on defining goals for circuit behavior to be met as part of the design process. To increase the accuracy of analog computation, we develop techniques for creating compensated circuit building blocks, where compensation implies the cancellation of device variations, offsets, and nonlinearities. These compensated building blocks can be used as components in larger and more complex circuits, which can then also be compensated. To this end, we develop techniques for automatically determining appropriate parameters for circuits, using constrained optimization. We also fabricate circuits that implement multi-dimensional gradient estimation for a gradient descent optimization technique. The parameter-setting and optimization tools allow us to automatically choose values for compensating our circuit building blocks, based on our goals for the circuit performance. We can also use the techniques to optimize parameters for larger systems, applying the goal-based techniques hierarchically. We also describe a set of thought experiments involving circuit techniques for increasing the precision of analog computation. Our engineering design methodology is a step toward easier use of analog VLSI to solve problems in computer graphics and neural networks. We provide data measured from compensated multipliers built using these design techniques. To demonstrate the feasibility of using analog VLSI for more quantitative computation, we develop small applications using the goal-based design approach and compensated components. Finally, we conclude by discussing the expected significance of this work for the wider use of analog VLSI for
National Aeronautics and Space Administration — The objective of this project was to use GPU enabled computing to accelerate the analyses of heat transfer and thermal effects. Graphical processing unit (GPU)...
Energy Technology Data Exchange (ETDEWEB)
Munro, J.K. Jr.
1980-05-01
The advent of large, fast computers has opened the way to modeling more complex physical processes and to handling very large quantities of experimental data. The amount of information that can be processed in a short period of time is so great that use of graphical displays assumes greater importance as a means of displaying this information. Information from dynamical processes can be displayed conveniently by use of animated graphics. This guide presents the basic techniques for generating black and white animated graphics, with consideration of aesthetic, mechanical, and computational problems. The guide is intended for use by someone who wants to make movies on the National Magnetic Fusion Energy Computing Center (NMFECC) CDC-7600. Problems encountered by a geographically remote user are given particular attention. Detailed information is given that will allow a remote user to do some file checking and diagnosis before giving graphics files to the system for processing into film in order to spot problems without having to wait for film to be delivered. Source listings of some useful software are given in appendices along with descriptions of how to use it. 3 figures, 5 tables.
Discrete-time dynamic graphical games:model-free reinforcement learning solution
Institute of Scientific and Technical Information of China (English)
Mohammed I ABOUHEAF; Frank L LEWIS; Magdi S MAHMOUD; Dariusz G MIKULSKI
2015-01-01
This paper introduces a model-free reinforcement learning technique that is used to solve a class of dynamic games known as dynamic graphical games. The graphical game results from multi-agent dynamical systems, where pinning control is used to make all the agents synchronize to the state of a command generator or a leader agent. Novel coupled Bellman equations and Hamiltonian functions are developed for the dynamic graphical games. The Hamiltonian mechanics are used to derive the necessary conditions for optimality. The solution for the dynamic graphical game is given in terms of the solution to a set of coupled Hamilton-Jacobi-Bellman equations developed herein. Nash equilibrium solution for the graphical game is given in terms of the solution to the underlying coupled Hamilton-Jacobi-Bellman equations. An online model-free policy iteration algorithm is developed to learn the Nash solution for the dynamic graphical game. This algorithm does not require any knowledge of the agents’ dynamics. A proof of convergence for this multi-agent learning algorithm is given under mild assumption about the inter-connectivity properties of the graph. A gradient descent technique with critic network structures is used to implement the policy iteration algorithm to solve the graphical game online in real-time.
X based interactive computer graphics applications for aerodynamic design and education
Benson, Thomas J.; Higgs, C. Fred, III
1995-01-01
Six computer applications packages have been developed to solve a variety of aerodynamic problems in an interactive environment on a single workstation. The packages perform classical one dimensional analysis under the control of a graphical user interface and can be used for preliminary design or educational purposes. The programs were originally developed on a Silicon Graphics workstation and used the GL version of the FORMS library as the graphical user interface. These programs have recently been converted to the XFORMS library of X based graphics widgets and have been tested on SGI, IBM, Sun, HP and PC-Lunix computers. The paper will show results from the new VU-DUCT program as a prime example. VU-DUCT has been developed as an educational package for the study of subsonic open and closed loop wind tunnels.
Dynamic Graphics in Excel for Teaching Statistics: Understanding the Probability Density Function
Coll-Serrano, Vicente; Blasco-Blasco, Olga; Alvarez-Jareno, Jose A.
2011-01-01
In this article, we show a dynamic graphic in Excel that is used to introduce an important concept in our subject, Statistics I: the probability density function. This interactive graphic seeks to facilitate conceptual understanding of the main aspects analysed by the learners.
THE TYPES OF COMPUTER GRAPHICS AND THEIR APPLICATION AT DIFFERENT LEVELS OF KNOWLEDGE
Directory of Open Access Journals (Sweden)
Anna Makarewicz
2015-11-01
Full Text Available In this article we introduce the concept of computer graphics and graphical application C.a.R (Compasses and Ruler, its basic commands and several examples associated with the geometry. This subject is at all levels of knowledge in various stages of development. We will present the C.a.R possibilities that can be used in secondary schools, high schools and colleges. We show function graphs of varying degrees of difficulty that are too complicated for the human imagination.
Design for scalability in 3D computer graphics architectures
DEFF Research Database (Denmark)
Holten-Lund, Hans Erik
2002-01-01
been developed. Hybris is a prototype rendering architeture which can be tailored to many specific 3D graphics applications and implemented in various ways. Parallel software implementations for both single and multi-processor Windows 2000 system have been demonstrated. Working hardware/software...... codesign implementations of Hybris for standard-cell based ASIC (simulated) and FPGA technologies have been demonstrated, using manual co-synthesis for translation of a Virtual Prototyping architecture specification written in C into both optimized C source for software and into to a synthesizable VHDL...... specification for hardware implementation. A flexible VRML 97 3D scene graph engine with a Java interface and C++ interface has been implemented to allow flexible integration of the rendering technology into Java and C++ applications. A 3D medical visualization workstation prototype (3D-Med) is examined...
Time-of-Flight Cameras in Computer Graphics
DEFF Research Database (Denmark)
Kolb, Andreas; Barth, Erhardt; Koch, Reinhard
2010-01-01
A growing number of applications depend on accurate and fast 3D scene analysis. Examples are model and lightfield acquisition, collision prevention, mixed reality, and gesture recognition. The estimation of a range map by image analysis or laser scan techniques is still a time-consuming and expen...... devices” for gaming, web-conferencing, and numerous other applications. This STAR gives an account of recent developments in ToF-technology and discusses the current state of the integration of this technology into various graphics-related applications.......-consuming and expensive part of such systems. A lower-priced, fast and robust alternative for distance measurements are Time-of-Flight (ToF) cameras. Recently, significant advances have been made in producing low-cost and compact ToF-devices, which have the potential to revolutionize many fields of research, including...
Time-of-Flight Sensors in Computer Graphics
DEFF Research Database (Denmark)
Kolb, Andreas; Barth, Erhardt; Koch, Reinhard
2009-01-01
Abstract A growing number of applications depend on accurate and fast 3D scene analysis. Examples are model and lightfield acquisition, collision prevention, mixed reality, and gesture recognition. The estimation of a range map by image analysis or laser scan techniques is still a time-consuming ......-time geometry devices” for gaming, web-conferencing, and numerous other applications. This STAR gives an account of recent developments in ToF-technology and discusses the current state of the integration of this technology into various graphics-related applications.......-consuming and expensive part of such systems. A lower-priced, fast and robust alternative for distance measurements are Time-of-Flight (ToF) cameras. Recently, significant improvements have been made in order to achieve low-cost and compact ToF-devices, that have the potential to revolutionize many fields of research...
Attention and visual memory in visualization and computer graphics.
Healey, Christopher G; Enns, James T
2012-07-01
A fundamental goal of visualization is to produce images of data that support visual analysis, exploration, and discovery of novel insights. An important consideration during visualization design is the role of human visual perception. How we "see" details in an image can directly impact a viewer's efficiency and effectiveness. This paper surveys research on attention and visual perception, with a specific focus on results that have direct relevance to visualization and visual analytics. We discuss theories of low-level visual perception, then show how these findings form a foundation for more recent work on visual memory and visual attention. We conclude with a brief overview of how knowledge of visual attention and visual memory is being applied in visualization and graphics. We also discuss how challenges in visualization are motivating research in psychophysics.
ResidPlots-2: Computer Software for IRT Graphical Residual Analyses
Liang, Tie; Han, Kyung T.; Hambleton, Ronald K.
2009-01-01
This article discusses the ResidPlots-2, a computer software that provides a powerful tool for IRT graphical residual analyses. ResidPlots-2 consists of two components: a component for computing residual statistics and another component for communicating with users and for plotting the residual graphs. The features of the ResidPlots-2 software are…
Application of Computer Graphics to Graphing in Algebra and Trigonometry. Final Report.
Morris, J. Richard
This project was designed to improve the graphing competency of students in elementary algebra, intermediate algebra, and trigonometry courses at Virginia Commonwealth University. Computer graphics programs were designed using an Apple II Plus computer and implemented using Pascal. The software package is interactive and gives students control…
Robinson, Daniel H.; Schraw, Gregory
1994-01-01
Three experiments involving 138 college students investigated why one type of graphic organizer (a matrix) may communicate interconcept relations better than an outline or text. Results suggest that a matrix is more computationally efficient than either outline or text, allowing the easier computation of relationships. (SLD)
Incorporating modern OpenGL into computer graphics education.
Reina, Guido; Muller, Thomas; Ertl, Thomas
2014-01-01
University of Stuttgart educators have updated three computer science courses to incorporate forward-compatible OpenGL. To help students, they developed an educational framework that abstracts some of modern OpenGL's difficult aspects.
Magoules, Frederic
2011-01-01
Exploring new variations of classical methods as well as recent approaches appearing in the field, Computational Fluid Dynamics demonstrates the extensive use of numerical techniques and mathematical models in fluid mechanics. It presents various numerical methods, including finite volume, finite difference, finite element, spectral, smoothed particle hydrodynamics (SPH), mixed-element-volume, and free surface flow.Taking a unified point of view, the book first introduces the basis of finite volume, weighted residual, and spectral approaches. The contributors present the SPH method, a novel ap
Essential Computational Fluid Dynamics
Zikanov, Oleg
2011-01-01
This book serves as a complete and self-contained introduction to the principles of Computational Fluid Dynamic (CFD) analysis. It is deliberately short (at approximately 300 pages) and can be used as a text for the first part of the course of applied CFD followed by a software tutorial. The main objectives of this non-traditional format are: 1) To introduce and explain, using simple examples where possible, the principles and methods of CFD analysis and to demystify the `black box’ of a CFD software tool, and 2) To provide a basic understanding of how CFD problems are set and
Peng, Fei; Li, Jiao-ting; Long, Min
2015-03-01
To discriminate the acquisition pipelines of digital images, a novel scheme for the identification of natural images and computer-generated graphics is proposed based on statistical and textural features. First, the differences between them are investigated from the view of statistics and texture, and 31 dimensions of feature are acquired for identification. Then, LIBSVM is used for the classification. Finally, the experimental results are presented. The results show that it can achieve an identification accuracy of 97.89% for computer-generated graphics, and an identification accuracy of 97.75% for natural images. The analyses also demonstrate the proposed method has excellent performance, compared with some existing methods based only on statistical features or other features. The method has a great potential to be implemented for the identification of natural images and computer-generated graphics. © 2014 American Academy of Forensic Sciences.
A compute unified system architecture for graphics clusters incorporating data locality.
Müller, Christoph; Frey, Steffen; Strengert, Magnus; Dachsbacher, Carsten; Ertl, Thomas
2009-01-01
We present a development environment for distributed GPU computing targeted for multi-GPU systems, as well as graphics clusters. Our system is based on CUDA and logically extends its parallel programming model for graphics processors to higher levels of parallelism, namely, the PCI bus and network interconnects. While the extended API mimics the full function set of current graphics hardware-including the concept of global memory-on all distribution layers, the underlying communication mechanisms are handled transparently for the application developer. To allow for high scalability, in particular for network-interconnected environments, we introduce an automatic GPU-accelerated scheduling mechanism that is aware of data locality. This way, the overall amount of transmitted data can be heavily reduced, which leads to better GPU utilization and faster execution. We evaluate the performance and scalability of our system for bus and especially network-level parallelism on typical multi-GPU systems and graphics clusters.
Desktop computer graphics for RMS/payload handling flight design
Homan, D. J.
1984-01-01
A computer program, the Multi-Adaptive Drawings, Renderings and Similitudes (MADRAS) program, is discussed. The modeling program, written for a desktop computer system (the Hewlett-Packard 9845/C), is written in BASIC and uses modular construction of objects while generating both wire-frame and hidden-line drawings from any viewpoint. The dimensions and placement of objects are user definable. Once the hidden-line calculations are made for a particular viewpoint, the viewpoint may be rotated in pan, tilt, and roll without further hidden-line calculations. The use and results of this program are discussed.
Thermal model for discrete vegetation and its solution on pixel scale using computer graphics
Institute of Scientific and Technical Information of China (English)
苏红波; 张仁华; 唐新斋; 孙晓敏; 朱治林
2000-01-01
In this paper, we discuss how the multi-reflection of thermal emission affects the calculation of radiation balance. With the help of computer graphics, the four components of discrete vegetation are analyzed in detail and the curves of BRDF for the discrete vegetation can be obtained as well. A new model is put forward to inverse the temperatures of four components. The solution obtained by using computer graphics is consistent with observations in the field experiment in Yucheng Remote Sensing Comprehensive Site of CAS. Furthermore, the method can be used to retrieve land surface temperature based on multi-angle thermal infrared remotely sensed data.
Thermal model for discrete vegetation and its solution on pixel scale using computer graphics
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
In this paper,we discuss how the multi-reflection of thermal emission affects the calculation of radiation balance.With the help of computer graphics,the four components of discrete vegetation are analyzed in detail and the curves of BRDF for the discrete vegetation can be obtained as well.A new model is put forward to inverse the temperatures of four components.The solution obtained by using computer graphics is consistent with observations in the field experiment in Yucheng Remote Sensing Comprehensive Site of CAS.Furthermore,the method can be used to retrieve land surface temperature based on multi-angle thermal infrared remotely sensed data.
Graphical Visualization on Computational Simulation Using Shared Memory
Lima, A. B.; Correa, Eberth
2014-03-01
The Shared Memory technique is a powerful tool for parallelizing computer codes. In particular it can be used to visualize the results "on the fly" without stop running the simulation. In this presentation we discuss and show how to use the technique conjugated with a visualization code using openGL.
An Architectural Design System Based on Computer Graphics.
MacDonald, Stephen L.; Wehrli, Robert
The recent developments in computer hardware and software are presented to inform architects of this design tool. Technical advancements in equipment include--(1) cathode ray tube displays, (2) light pens, (3) print-out and photo copying attachments, (4) controls for comparison and selection of images, (5) chording keyboards, (6) plotters, and (7)…
Computational fluid dynamic applications
Energy Technology Data Exchange (ETDEWEB)
Chang, S.-L.; Lottes, S. A.; Zhou, C. Q.
2000-04-03
The rapid advancement of computational capability including speed and memory size has prompted the wide use of computational fluid dynamics (CFD) codes to simulate complex flow systems. CFD simulations are used to study the operating problems encountered in system, to evaluate the impacts of operation/design parameters on the performance of a system, and to investigate novel design concepts. CFD codes are generally developed based on the conservation laws of mass, momentum, and energy that govern the characteristics of a flow. The governing equations are simplified and discretized for a selected computational grid system. Numerical methods are selected to simplify and calculate approximate flow properties. For turbulent, reacting, and multiphase flow systems the complex processes relating to these aspects of the flow, i.e., turbulent diffusion, combustion kinetics, interfacial drag and heat and mass transfer, etc., are described in mathematical models, based on a combination of fundamental physics and empirical data, that are incorporated into the code. CFD simulation has been applied to a large variety of practical and industrial scale flow systems.
Computer Graphics For CT-Assisted Knee Surgery
Rhodes, Michael L.; Jackson, Douglas W.; Azzawi, Yu-Ming; Glenn, William V.; Howland, Robert S.; Rothman, Stephen L.
1984-08-01
Computed tomography (CT) scanners provide images of internal anatomy with unsurpassed spatial resolution. Since these images are inherently digital, computer systems can be used to simulate, plan, and guide surgical procedures to submillimeter precision. The combination of CT images, specially designed instruments, and the software to coordinate them results in improved accuracy for stereotactic surgery. This paper introduces per cutaneous cruciate ligament replacement as a new application for computer-aided ster eotaxi s. The procedure is described here with the knee firmly attached to a custom device. Twenty-five to thirty CT scans are performed to view the knee in detail, with special care taken to visualize the cruciate ligaments and their attachment to the tibia and femur. At the display console, two trajectories are chosen, using images delivered by the scanner and alternative views generated by software. These trajectories position two attachment shafts through skeletal structure in the knee to secure a replacement cruciate ligament. Interaction is illustrated that allows both the selection of the trajectories and the simulated surgery along their path. Anatomy intersected by the proposed trajectories can be reviewed in detail prior to actual surgery. Once reviewed, frame sittings are delivered by the computer system to drill the ligament attachment shafts. A replacement cruciate ligament can be passed through these two drill holes. Only an arthroscopic procedure is needed for later fixation of the ligament. In this manner, 4-6 hour open surgery of the knee is avoided and patient rehabilitation should be reduced from several months to 4-5 weeks. The frame, software, procedure, and computational aspects of the interaction are described. Test and patient results are given.
Chen, Maomao; Zhang, Jiulou; Cai, Chuangjian; Gao, Yang; Luo, Jianwen
2016-06-01
Dynamic fluorescence molecular tomography (DFMT) is a valuable method to evaluate the metabolic process of contrast agents in different organs in vivo, and direct reconstruction methods can improve the temporal resolution of DFMT. However, challenges still remain due to the large time consumption of the direct reconstruction methods. An acceleration strategy using graphics processing units (GPU) is presented. The procedure of conjugate gradient optimization in the direct reconstruction method is programmed using the compute unified device architecture and then accelerated on GPU. Numerical simulations and in vivo experiments are performed to validate the feasibility of the strategy. The results demonstrate that, compared with the traditional method, the proposed strategy can reduce the time consumption by ˜90% without a degradation of quality.
COMPUTER GRAPHICAL REPRESENTATION, IN TREBLE ORTHOGONAL PROJECTION, OF A POINT
Directory of Open Access Journals (Sweden)
SLONOVSCHI Andrei
2017-05-01
Full Text Available In the stages of understanding and study, by students, of descriptive geometry, the treble orthogonal projection of a point, creates problems in the situations in that one or more descriptive coordinates are zero. Starting from these considerations the authors have created an original computer program which offers to the students the possibility to easily understanding of the way in which a point is represented, in draught, in the treble orthogonal projection whatever which are its values of the descriptive coordinates.
Accelerating Missile Threat Engagement Simulations Using Personal Computer Graphics Cards
2005-03-01
personal computer on the market today, have reached a level of power and programmability that enables them to be used as high performance stream...expected to continue at this rate for another five years, perhaps achieving tera-FLOP performance by 2005 [Mac03]. While the main, market -driven...JEFFERS // 11 nov 04 -- multiplies 1x1 scene by 8x8 reticle pallette, then does // 4:1 redux; results in RT that is quarter sized of
Computing Science and Statistics. Volume 24. Graphics and Visualization
1993-03-01
1990), Fractal Geometry, Mathematical Figure 15: Core corresponding to this portion of the sonic Foundations and Aplications ., John Wil-’ and Sons...object affect SAS 6.03 and SPSS 4.0 are used in computing center the behavior of the object when it is executed or when subnet; however, Mathematica 1.0... SPSS Inc. Nacogdoches, TX 75961 444 North Michigan Ave jmgarner@sfaustin.bitnet Oak Park. IL 60304 sher @spss.com Alan E. Gelfand University of
Ratschek, H
2003-01-01
This undergraduate and postgraduate text will familiarise readers with interval arithmetic and related tools to gain reliable and validated results and logically correct decisions for a variety of geometric computations plus the means for alleviating the effects of the errors. It also considers computations on geometric point-sets, which are neither robust nor reliable in processing with standard methods. The authors provide two effective tools for obtaining correct results: (a) interval arithmetic, and (b) ESSA the new powerful algorithm which improves many geometric computations and makes th
Parallel computing for simultaneous iterative tomographic imaging by graphics processing units
Bello-Maldonado, Pedro D.; López, Ricardo; Rogers, Colleen; Jin, Yuanwei; Lu, Enyue
2016-05-01
In this paper, we address the problem of accelerating inversion algorithms for nonlinear acoustic tomographic imaging by parallel computing on graphics processing units (GPUs). Nonlinear inversion algorithms for tomographic imaging often rely on iterative algorithms for solving an inverse problem, thus computationally intensive. We study the simultaneous iterative reconstruction technique (SIRT) for the multiple-input-multiple-output (MIMO) tomography algorithm which enables parallel computations of the grid points as well as the parallel execution of multiple source excitation. Using graphics processing units (GPUs) and the Compute Unified Device Architecture (CUDA) programming model an overall improvement of 26.33x was achieved when combining both approaches compared with sequential algorithms. Furthermore we propose an adaptive iterative relaxation factor and the use of non-uniform weights to improve the overall convergence of the algorithm. Using these techniques, fast computations can be performed in parallel without the loss of image quality during the reconstruction process.
INTERDISCIPLINARY INTEGRATION IN THE COURSE OF STUDYING WEB TECHNOLOGIES AND COMPUTER GRAPHICS
Directory of Open Access Journals (Sweden)
Andrey V. Kolesnikov
2013-01-01
Full Text Available The expediency of interdisciplinary integration in large-scale introduction of the competence approach is substantiated. The methodology for interdisciplinary integration is presented in the article. The authors demonstrate this methodology on the example of two disciplines: «The development and maintenance of information web-resources» and «Computer Graphics and Multimedia.»
Computer graphics testbed to simulate and test vision systems for space applications
Cheatham, John B.
1991-01-01
Research activity has shifted from computer graphics and vision systems to the broader scope of applying concepts of artificial intelligence to robotics. Specifically, the research is directed toward developing Artificial Neural Networks, Expert Systems, and Laser Imaging Techniques for Autonomous Space Robots.
The Representation of Highly Non-Ideal Phase Equilibria Using Computer Graphics.
Charos, Georgios N.; And Others
1986-01-01
Previous work focused on use of computer graphics in teaching thermodynamic phase equilibria for classes I and II. Extends this work to include the considerably more non-ideal phase behavior shown by classes III, IV, and V. Student and instructor response has been overwhelmingly positive about the approach. (JN)
Some research advances in computer graphics that will enhance applications to engineering design
Allan, J. J., III
1975-01-01
Research in man/machine interactions and graphics hardware/software that will enhance applications to engineering design was described. Research aspects of executive systems, command languages, and networking used in the computer applications laboratory are mentioned. Finally, a few areas where little or no research is being done were identified.
Three-Dimensional Computer Animated Graphics: A Tool for Spatial Skill Instruction.
Zavotka, Susan Lee
1987-01-01
Describes study of home economics students at Ohio State University that investigated whether computer animated graphics that replicate mental images of rotation and dimensional transformation would be useful in the development of spatial skills. Orthographic drawings are described, and results for treatment and control groups are analyzed. (29…
Goodson-Espy, Tracy; Lynch-Davis, Kathleen; Schram, Pamela; Quickenton, Art
2010-01-01
This paper describes the genesis and purpose of our geometry methods course, focusing on a geometry-teaching technology we created using NVIDIA[R] Chameleon demonstration. This article presents examples from a sequence of lessons centered about a 3D computer graphics demonstration of the chameleon and its geometry. In addition, we present data…
The Basic Concepts of Three-Dimensional Computer Graphics for Artists.
Sachter, Judy E.
Arguing that an artist using any new medium must understand its techniques and limitations, this master's thesis is intended to demystify state-of-the-art 3-D computer graphics through a discussion of the technical literature from the artist's point of view and an analysis of the curricular needs of the artist. The first of six chapters discusses…
Emphasizing Planning for Essay Writing with a Computer-Based Graphic Organizer
Evmenova, Anya S.; Regan, Kelley; Boykin, Andrea; Good, Kevin; Hughes, Melissa; MacVittie, Nichole; Sacco, Donna; Ahn, Soo Y.; Chirinos, David
2016-01-01
The authors conducted a multiple-baseline study to investigate the effects of a computer-based graphic organizer (CBGO) with embedded self-regulated learning strategies on the quantity and quality of persuasive essay writing by students with high-incidence disabilities. Ten seventh- and eighth-grade students with learning disabilities, emotional…
Ivanov, Anisoara; Neacsu, Andrei
2011-01-01
This study describes the possibility and advantages of utilizing simple computer codes to complement the teaching techniques for high school physics. The authors have begun working on a collection of open source programs which allow students to compare the results and graphics from classroom exercises with the correct solutions and further more to…
Computer-Based Dynamic Assessment of Multidigit Multiplication.
Gerber, Michael M.; And Others
1994-01-01
Design details, operation, and initial field test results are reported for DynaMath, a computer-based dynamic assessment system that provides individually tailored, instructionally useful assessment of students with disabilities. DynaMath organizes and outputs student performance data, graphically shows the "zone of proximal…
A computer graphics display technique for the examination of aircraft design data
Talcott, N. A., Jr.
1981-01-01
An interactive computer graphics technique has been developed for quickly sorting and interpreting large amounts of aerodynamic data. It utilizes a graphic representation rather than numbers. The geometry package represents the vehicle as a set of panels. These panels are ordered in groups of ascending values (e.g., equilibrium temperatures). The groups are then displayed successively on a CRT building up to the complete vehicle. A zoom feature allows for displaying only the panels with values between certain limits. The addition of color allows a one-time display thus eliminating the need for a display build up.
Jones, R. H.
1984-01-01
The hardware and software developments in computer graphics are discussed. Major topics include: system capabilities, hardware design, system compatibility, and software interface with the data base management system.
A Knowledge Modeling Method for Computer Graphics Design & Production Based on Ontology
Directory of Open Access Journals (Sweden)
Chen Tong
2017-01-01
Full Text Available As one of the most critical stages of CG (Computer Graphics industry, CG design & production needs the support of professional knowledge and practice experience of multidisciplinary. With the outstanding performance in knowledge sharing, integration and reuse, knowledge modeling could increase greatly the efficiency, reduce the cost and avoid repeated error in CG design & production. However, knowledge modeling of CG design & production differs greatly from those of other fields. On the one hand, it is similar to physical product design, which involves great deal of tacit knowledge such as modeling skills, reasoning knowledge and so on. On the other hand, as film, CG design & production needs a lot of unstructured description information. The heterogeneity between physical product and film makes knowledge modeling more complicated. Thus a systematic knowledge modelling method based on Ontology is proposed to aid CG design & production in this paper. CG animation knowledge is capture and organized from viewpoint of three aspects: requirements and design and production. The knowledge are categorized into static and dynamic knowledge, and Ontology is adopted to construct a hierarchic model to organize the knowledge, so as to offer a uniform communication semantic foundations for designers from different fields. Based on animation script, the CG design task model is proposed to drive the organization and management of different knowledge involved in CG design & production. Finally, we apply this method in the knowledge modeling of naked-eye animation design and production to illustrate effectiveness of this method.
2D-dynamic representation of DNA sequences as a graphical tool in bioinformatics
Bielińska-WaÌ§Ż, D.; WaÌ§Ż, P.
2016-10-01
2D-dynamic representation of DNA sequences is briefly reviewed. Some new examples of 2D-dynamic graphs which are the graphical tool of the method are shown. Using the examples of the complete genome sequences of the Zika virus it is shown that the present method can be applied for the study of the evolution of viral genomes.
Mathematics of shape description a morphological approach to image processing and computer graphics
Ghosh, Pijush K
2009-01-01
Image processing problems are often not well defined because real images are contaminated with noise and other uncertain factors. In Mathematics of Shape Description, the authors take a mathematical approach to address these problems using the morphological and set-theoretic approach to image processing and computer graphics by presenting a simple shape model using two basic shape operators called Minkowski addition and decomposition. This book is ideal for professional researchers and engineers in Information Processing, Image Measurement, Shape Description, Shape Representation and Computer Graphics. Post-graduate and advanced undergraduate students in pure and applied mathematics, computer sciences, robotics and engineering will also benefit from this book. Key FeaturesExplains the fundamental and advanced relationships between algebraic system and shape description through the set-theoretic approachPromotes interaction of image processing geochronology and mathematics in the field of algebraic geometryP...
3D-CT vascular setting protocol using computer graphics for the evaluation of maxillofacial lesions
Directory of Open Access Journals (Sweden)
CAVALCANTI Marcelo de Gusmão Paraiso
2001-01-01
Full Text Available In this paper we present the aspect of a mandibular giant cell granuloma in spiral computed tomography-based three-dimensional (3D-CT reconstructed images using computer graphics, and demonstrate the importance of the vascular protocol in permitting better diagnosis, visualization and determination of the dimensions of the lesion. We analyzed 21 patients with maxillofacial lesions of neoplastic and proliferative origins. Two oral and maxillofacial radiologists analyzed the images. The usefulness of interactive 3D images reconstructed by means of computer graphics, especially using a vascular setting protocol for qualitative and quantitative analyses for the diagnosis, determination of the extent of lesions, treatment planning and follow-up, was demonstrated. The technique is an important adjunct to the evaluation of lesions in relation to axial CT slices and 3D-CT bone images.
Experiments with a low-cost system for computer graphics material model acquisition
Rushmeier, Holly; Lockerman, Yitzhak; Cartwright, Luke; Pitera, David
2015-03-01
We consider the design of an inexpensive system for acquiring material models for computer graphics rendering applications in animation, games and conceptual design. To be useful in these applications a system must be able to model a rich range of appearances in a computationally tractable form. The range of appearance of interest in computer graphics includes materials that have spatially varying properties, directionality, small-scale geometric structure, and subsurface scattering. To be computationally tractable, material models for graphics must be compact, editable, and efficient to numerically evaluate for ray tracing importance sampling. To construct appropriate models for a range of interesting materials, we take the approach of separating out directly and indirectly scattered light using high spatial frequency patterns introduced by Nayar et al. in 2006. To acquire the data at low cost, we use a set of Raspberry Pi computers and cameras clamped to miniature projectors. We explore techniques to separate out surface and subsurface indirect lighting. This separation would allow the fitting of simple, and so tractable, analytical models to features of the appearance model. The goal of the system is to provide models for physically accurate renderings that are visually equivalent to viewing the original physical materials.
Development of training support system based on three-dimensional computer graphics technology
Energy Technology Data Exchange (ETDEWEB)
Kude, Akizumi; Hanafusa, Hidemitsu; Matsuoka, Yoshinori; Shirute, Ikuo [Institute of Nuclear Safety System Inc., Seika, Kyoto (Japan); Ogura, Kazuhide
1998-09-01
Recently, Virtual Reality (VR) technology has developed quickly, together with research conducted on various elemental and related technologies and research in various fields of its application. In particular, the development of computer graphics (CG) technology at the same pace as the progress in computer performance is remarkable. We have developed a new type of training support system using three-dimensional (3D) CG technology. It is the training support system for disassembling and assembling a motor-operated gate valve. The training support system proposed is based on a personal computer and can be used easily by anyone. The system configuration is outlined herein. (author)
An evolving infrastructure for scientific computing and the integration of new graphics technology
Energy Technology Data Exchange (ETDEWEB)
Fong, K.W.
1993-02-01
The National Energy Research Supercomputer Center (NERSC) at the Lawrence Livermore National Laboratory is currently pursuing several projects to implement and integrate new hardware and software technologies. While each of these projects ought to be and is in fact individually justifiable, there is an appealing metaphor for viewing them collectively which provides a simple and memorable way to understand the future direction not only of supercomputing services but of computer centers in general. Once this general direction is understood, it becomes clearer what future computer graphics technologies would be possible and desirable, at least within the context of large scale scientific computing.
Lindert, Steffen; Bucher, Denis; Eastman, Peter; Pande, Vijay; McCammon, J Andrew
2013-11-12
The accelerated molecular dynamics (aMD) method has recently been shown to enhance the sampling of biomolecules in molecular dynamics (MD) simulations, often by several orders of magnitude. Here, we describe an implementation of the aMD method for the OpenMM application layer that takes full advantage of graphics processing units (GPUs) computing. The aMD method is shown to work in combination with the AMOEBA polarizable force field (AMOEBA-aMD), allowing the simulation of long time-scale events with a polarizable force field. Benchmarks are provided to show that the AMOEBA-aMD method is efficiently implemented and produces accurate results in its standard parametrization. For the BPTI protein, we demonstrate that the protein structure described with AMOEBA remains stable even on the extended time scales accessed at high levels of accelerations. For the DNA repair metalloenzyme endonuclease IV, we show that the use of the AMOEBA force field is a significant improvement over fixed charged models for describing the enzyme active-site. The new AMOEBA-aMD method is publicly available (http://wiki.simtk.org/openmm/VirtualRepository) and promises to be interesting for studying complex systems that can benefit from both the use of a polarizable force field and enhanced sampling.
Energy Technology Data Exchange (ETDEWEB)
Matsuda, Y.; Usagawa, Y.; Kawamoto, A. [Chugoku Electric Power Co. Inc., Hiroshima (Japan)
1996-10-25
In order to obtain the understanding of residents around sites for landscape images in construction of power plants, substations and transmission lines, preparation of supposed landscape images was studied using computer graphics (CG). The system developed on a graphics workstation in 1994 was expensive and poorer in operability than PC although real clear images were obtained. The system was thus improved to be usable on PC. The improved system is usable on OA systems in offices, and possible to transmit image data and print out high-quality images. In addition, the system offers the preparation function of facility layouts and computer graphics. The system is featured by necessary training only for 2-3 days, lower cost and necessary lower initial investment. Since its user interface was, in particular, considered to make it possible for designers to easily operate and timely cope with demands of residents, flexible selection out of various cases, rapid simulation and efficient business became possible. 3 refs., 3 figs., 5 tabs.
GALE: a graphics assisted learning environment for computer-based interactive videodisc education.
Cutts, J H; Hazelwood, S E; Mitchell, J A; Bridges, A J; Reid, J C
1992-08-01
GALE, a Graphics Assisted Learning Environment, is a computer-based interactive videodisc authoring tool. GALE was created as the authoring package for AI/LEARN/Rheumatology, an independent study system for teaching rheumatology to medical trainees. GALE has potential widespread application beyond rheumatology. Interactive videodisc technology is a prime feature of GALE. Other highlights are: WordPerfect macros which simplify programming, graphics-based large text characters, tracking of user responses, hypertext-like definition capabilities, color coded screens to distinguish between hypertext branches and the mainstream of the course content and ability to overlay text on the video image. GALE runs on a PC-compatible computer with selected Pioneer LaserDisc players. GALE uses WordPerfect 5.1 for text editing and has been designed for use by non-programmers.
Realization of the Evristic Combination Methods by Means of Computer Graphics
Directory of Open Access Journals (Sweden)
S. A. Novoselov
2012-01-01
Full Text Available The paper looks at the ways of enhancing and stimulating the creative activity and initiative of pedagogic students – the prospective specialists called for educating and upbringing socially and professionally competent, originally thinking, versatile personalities. For developing their creative abilities the author recommends introducing the heuristic combination methods, applied for engineering creativity facilitation; associative-synectic technology; and computer graphics tools. The paper contains the comparative analysis of the main heuristic method operations and the computer graphics redactor in creating a visual composition. The examples of implementing the heuristic combination methods are described along with the extracts of the laboratory classes designed for creativity and its motivation developments. The approbation of the given method in the several universities confirms the prospects of enhancing the students’ learning and creative activities.
Murrell, Paul
2005-01-01
R is revolutionizing the world of statistical computing. Powerful, flexible, and best of all free, R is now the program of choice for tens of thousands of statisticians. Destined to become an instant classic, R Graphics presents the first complete, authoritative exposition on the R graphical system. Paul Murrell, widely known as the leading expert on R graphics, has developed an in-depth resource that takes nothing for granted and helps both neophyte and seasoned users master the intricacies of R graphics. After an introductory overview of R graphics facilities, the presentation first focuses
Development of automation and robotics for space via computer graphic simulation methods
Fernandez, Ken
1988-01-01
A robot simulation system, has been developed to perform automation and robotics system design studies. The system uses a procedure-oriented solid modeling language to produce a model of the robotic mechanism. The simulator generates the kinematics, inverse kinematics, dynamics, control, and real-time graphic simulations needed to evaluate the performance of the model. Simulation examples are presented, including simulation of the Space Station and the design of telerobotics for the Orbital Maneuvering Vehicle.
Three dimensional analysis of coelacanth body structure by computer graphics and X-ray CT images
Energy Technology Data Exchange (ETDEWEB)
Suzuki, Naoki (Jikei Univ., Tokyo (Japan). School of Medicine); Hamada, Takashi
1990-06-01
Three dimensional imaging processes were applied for the structural and functional analyses of the modern coelacanth (Latimeria chalumnae). Visualization of the obtained images is performed with computer graphics on the basis of serial images by an X-ray CT scanning method. Reconstruction of three dimensional images of the body structure of coelacanth using the volume rendering and surface rendering methods provides us various information about external and internal shapes of this exquisite fish. (author).
The convergence of robotics, vision, and computer graphics for user interaction
Energy Technology Data Exchange (ETDEWEB)
Hollerback, J.M.; Thompson, W.B.; Shirley, P.
1999-11-01
Mechanical interfaces to virtual environments and the creation of virtual environments represent important and relatively new application areas for robotics. The creation of immersive interfaces will require codevelopment of visual displays that complement mechanical stimuli with appropriate visual cues, ultimately determined from human psychophysics. Advances in interactive rendering and geometric modeling form computer graphics will play a key role. Examples are drawn from haptic and locomotion interface projects.
Introduction to regression graphics
Cook, R Dennis
2009-01-01
Covers the use of dynamic and interactive computer graphics in linear regression analysis, focusing on analytical graphics. Features new techniques like plot rotation. The authors have composed their own regression code, using Xlisp-Stat language called R-code, which is a nearly complete system for linear regression analysis and can be utilized as the main computer program in a linear regression course. The accompanying disks, for both Macintosh and Windows computers, contain the R-code and Xlisp-Stat. An Instructor's Manual presenting detailed solutions to all the problems in the book is ava
Real-time 3D computed tomographic reconstruction using commodity graphics hardware
Xu, Fang; Mueller, Klaus
2007-07-01
The recent emergence of various types of flat-panel x-ray detectors and C-arm gantries now enables the construction of novel imaging platforms for a wide variety of clinical applications. Many of these applications require interactive 3D image generation, which cannot be satisfied with inexpensive PC-based solutions using the CPU. We present a solution based on commodity graphics hardware (GPUs) to provide these capabilities. While GPUs have been employed for CT reconstruction before, our approach provides significant speedups by exploiting the various built-in hardwired graphics pipeline components for the most expensive CT reconstruction task, backprojection. We show that the timings so achieved are superior to those obtained when using the GPU merely as a multi-processor, without a drop in reconstruction quality. In addition, we also show how the data flow across the graphics pipeline can be optimized, by balancing the load among the pipeline components. The result is a novel streaming CT framework that conceptualizes the reconstruction process as a steady flow of data across a computing pipeline, updating the reconstruction result immediately after the projections have been acquired. Using a single PC equipped with a single high-end commodity graphics board (the Nvidia 8800 GTX), our system is able to process clinically-sized projection data at speeds meeting and exceeding the typical flat-panel detector data production rates, enabling throughput rates of 40-50 projections s-1 for the reconstruction of 5123 volumes.
Real-time 3D computed tomographic reconstruction using commodity graphics hardware
Energy Technology Data Exchange (ETDEWEB)
Xu Fang; Mueller, Klaus [Center for Visual Computing, Computer Science Department, Stony Brook University, Stony Brook, NY 11794-4400 (United States)
2007-07-21
The recent emergence of various types of flat-panel x-ray detectors and C-arm gantries now enables the construction of novel imaging platforms for a wide variety of clinical applications. Many of these applications require interactive 3D image generation, which cannot be satisfied with inexpensive PC-based solutions using the CPU. We present a solution based on commodity graphics hardware (GPUs) to provide these capabilities. While GPUs have been employed for CT reconstruction before, our approach provides significant speedups by exploiting the various built-in hardwired graphics pipeline components for the most expensive CT reconstruction task, backprojection. We show that the timings so achieved are superior to those obtained when using the GPU merely as a multi-processor, without a drop in reconstruction quality. In addition, we also show how the data flow across the graphics pipeline can be optimized, by balancing the load among the pipeline components. The result is a novel streaming CT framework that conceptualizes the reconstruction process as a steady flow of data across a computing pipeline, updating the reconstruction result immediately after the projections have been acquired. Using a single PC equipped with a single high-end commodity graphics board (the Nvidia 8800 GTX), our system is able to process clinically-sized projection data at speeds meeting and exceeding the typical flat-panel detector data production rates, enabling throughput rates of 40-50 projections s{sup -1} for the reconstruction of 512{sup 3} volumes.
Dynamical Systems Some Computational Problems
Guckenheimer, J; Guckenheimer, John; Worfolk, Patrick
1993-01-01
We present several topics involving the computation of dynamical systems. The emphasis is on work in progress and the presentation is informal -- there are many technical details which are not fully discussed. The topics are chosen to demonstrate the various interactions between numerical computation and mathematical theory in the area of dynamical systems. We present an algorithm for the computation of stable manifolds of equilibrium points, describe the computation of Hopf bifurcations for equilibria in parametrized families of vector fields, survey the results of studies of codimension two global bifurcations, discuss a numerical analysis of the Hodgkin and Huxley equations, and describe some of the effects of symmetry on local bifurcation.
Thorp, Scott A.
1992-01-01
This presentation will discuss the development of a NASA Geometry Exchange Specification for transferring aerodynamic surface geometry between LeRC systems and grid generation software used for computational fluid dynamics research. The proposed specification is based on a subset of the Initial Graphics Exchange Specification (IGES). The presentation will include discussion of how the NASA-IGES standard will accommodate improved computer aided design inspection methods and reverse engineering techniques currently being developed. The presentation is in viewgraph format.
Coulam, C. M.; Dunnette, W. H.; Wood, E. H.
1970-01-01
Two methods whereby a digital computer may be used to regulate a scintiscanning process are discussed from the viewpoint of computer input-output software. The computer's function, in this case, is to govern the data acquisition and storage, and to display the results to the investigator in a meaningful manner, both during and subsequent to the scanning process. Several methods (such as three-dimensional maps, contour plots, and wall-reflection maps) have been developed by means of which the computer can graphically display the data on-line, for real-time monitoring purposes, during the scanning procedure and subsequently for detailed analysis of the data obtained. A computer-governed method for converting scintiscan data recorded over the dorsal or ventral surfaces of the thorax into fractions of pulmonary blood flow traversing the right and left lungs is presented.
Energy Technology Data Exchange (ETDEWEB)
Jimenez, Edward Steven,
2013-09-01
The goal of this work is to develop a fast computed tomography (CT) reconstruction algorithm based on graphics processing units (GPU) that achieves significant improvement over traditional central processing unit (CPU) based implementations. The main challenge in developing a CT algorithm that is capable of handling very large datasets is parallelizing the algorithm in such a way that data transfer does not hinder performance of the reconstruction algorithm. General Purpose Graphics Processing (GPGPU) is a new technology that the Science and Technology (S&T) community is starting to adopt in many fields where CPU-based computing is the norm. GPGPU programming requires a new approach to algorithm development that utilizes massively multi-threaded environments. Multi-threaded algorithms in general are difficult to optimize since performance bottlenecks occur that are non-existent in single-threaded algorithms such as memory latencies. If an efficient GPU-based CT reconstruction algorithm can be developed; computational times could be improved by a factor of 20. Additionally, cost benefits will be realized as commodity graphics hardware could potentially replace expensive supercomputers and high-end workstations. This project will take advantage of the CUDA programming environment and attempt to parallelize the task in such a way that multiple slices of the reconstruction volume are computed simultaneously. This work will also take advantage of the GPU memory by utilizing asynchronous memory transfers, GPU texture memory, and (when possible) pinned host memory so that the memory transfer bottleneck inherent to GPGPU is amortized. Additionally, this work will take advantage of GPU-specific hardware (i.e. fast texture memory, pixel-pipelines, hardware interpolators, and varying memory hierarchy) that will allow for additional performance improvements.
Deng, Weiran; Yang, Cungeng; Stenger, V Andrew
2011-02-01
Multidimensional radiofrequency (RF) pulses are of current interest because of their promise for improving high-field imaging and for optimizing parallel transmission methods. One major drawback is that the computation time of numerically designed multidimensional RF pulses increases rapidly with their resolution and number of transmitters. This is critical because the construction of multidimensional RF pulses often needs to be in real time. The use of graphics processing units for computations is a recent approach for accelerating image reconstruction applications. We propose the use of graphics processing units for the design of multidimensional RF pulses including the utilization of parallel transmitters. Using a desktop computer with four NVIDIA Tesla C1060 computing processors, we found acceleration factors on the order of 20 for standard eight-transmitter two-dimensional spiral RF pulses with a 64 × 64 excitation resolution and a 10-μsec dwell time. We also show that even greater acceleration factors can be achieved for more complex RF pulses. Copyright © 2010 Wiley-Liss, Inc.
Computer graphics testbed to simulate and test vision systems for space applications
Cheatham, John B.; Wu, Chris K.; Lin, Y. H.
1991-01-01
A system was developed for displaying computer graphics images of space objects and the use of the system was demonstrated as a testbed for evaluating vision systems for space applications. In order to evaluate vision systems, it is desirable to be able to control all factors involved in creating the images used for processing by the vision system. Considerable time and expense is involved in building accurate physical models of space objects. Also, precise location of the model relative to the viewer and accurate location of the light source require additional effort. As part of this project, graphics models of space objects such as the Solarmax satellite are created that the user can control the light direction and the relative position of the object and the viewer. The work is also aimed at providing control of hue, shading, noise and shadows for use in demonstrating and testing imaging processing techniques. The simulated camera data can provide XYZ coordinates, pitch, yaw, and roll for the models. A physical model is also being used to provide comparison of camera images with the graphics images.
Computer graphics testbed to simulate and test vision systems for space applications
Cheatham, John B.; Wu, Chris K.; Lin, Y. H.
1991-01-01
A system was developed for displaying computer graphics images of space objects and the use of the system was demonstrated as a testbed for evaluating vision systems for space applications. In order to evaluate vision systems, it is desirable to be able to control all factors involved in creating the images used for processing by the vision system. Considerable time and expense is involved in building accurate physical models of space objects. Also, precise location of the model relative to the viewer and accurate location of the light source require additional effort. As part of this project, graphics models of space objects such as the Solarmax satellite are created that the user can control the light direction and the relative position of the object and the viewer. The work is also aimed at providing control of hue, shading, noise and shadows for use in demonstrating and testing imaging processing techniques. The simulated camera data can provide XYZ coordinates, pitch, yaw, and roll for the models. A physical model is also being used to provide comparison of camera images with the graphics images.
The Fractal Geometry of Nature; Its Mathematical Basis and Application to Computer Graphics
1986-01-01
Euclidean n space has dimension n ) has no topological meaning whatsoever. This fundamental problem was answered in 1911 by Brouwer . He proved that... Leo . refresh rate (for a 30HZ display) of most raster graphics displays. "This of course would require an enormous computational power that does not...ZW5u ,.*" •Dr. Dnnald Grr*-itwrg. *" (in-n.’ll I ’nirrsty. Itbrograw (if Compulvr Graphirs. Ithaca. NY 14853 4l -8- Dr. Leo J. Guibas, Systems
High-power graphic computers for visual simulation: a real-time--rendering revolution
Kaiser, M. K.
1996-01-01
Advances in high-end graphics computers in the past decade have made it possible to render visual scenes of incredible complexity and realism in real time. These new capabilities make it possible to manipulate and investigate the interactions of observers with their visual world in ways once only dreamed of. This paper reviews how these developments have affected two preexisting domains of behavioral research (flight simulation and motion perception) and have created a new domain (virtual environment research) which provides tools and challenges for the perceptual psychologist. Finally, the current limitations of these technologies are considered, with an eye toward how perceptual psychologist might shape future developments.
Advances in Human-Computer Interaction: Graphics and Animation Components for Interface Design
Cipolla Ficarra, Francisco V.; Nicol, Emma; Cipolla-Ficarra, Miguel; Richardson, Lucy
We present an analysis of communicability methodology in graphics and animation components for interface design, called CAN (Communicability, Acceptability and Novelty). This methodology has been under development between 2005 and 2010, obtaining excellent results in cultural heritage, education and microcomputing contexts. In studies where there is a bi-directional interrelation between ergonomics, usability, user-centered design, software quality and the human-computer interaction. We also present the heuristic results about iconography and layout design in blogs and websites of the following countries: Spain, Italy, Portugal and France.
Computer Modelling of Dynamic Processes
Directory of Open Access Journals (Sweden)
B. Rybakin
2000-10-01
Full Text Available Results of numerical modeling of dynamic problems are summed in the article up. These problems are characteristic for various areas of human activity, in particular for problem solving in ecology. The following problems are considered in the present work: computer modeling of dynamic effects on elastic-plastic bodies, calculation and determination of performances of gas streams in gas cleaning equipment, modeling of biogas formation processes.
Ufimtsev, Ivan S; Martinez, Todd J
2009-10-13
We demonstrate that a video gaming machine containing two consumer graphical cards can outpace a state-of-the-art quad-core processor workstation by a factor of more than 180× in Hartree-Fock energy + gradient calculations. Such performance makes it possible to run large scale Hartree-Fock and Density Functional Theory calculations, which typically require hundreds of traditional processor cores, on a single workstation. Benchmark Born-Oppenheimer molecular dynamics simulations are performed on two molecular systems using the 3-21G basis set - a hydronium ion solvated by 30 waters (94 atoms, 405 basis functions) and an aspartic acid molecule solvated by 147 waters (457 atoms, 2014 basis functions). Our GPU implementation can perform 27 ps/day and 0.7 ps/day of ab initio molecular dynamics simulation on a single desktop computer for these systems.
Sisto, Aaron; Glowacki, David R; Martinez, Todd J
2014-09-16
("fragmenting") a molecular system and then stitching it back together. In this Account, we address both of these problems, the first by using graphical processing units (GPUs) and electronic structure algorithms tuned for these architectures and the second by using an exciton model as a framework in which to stitch together the solutions of the smaller problems. The multitiered parallel framework outlined here is aimed at nonadiabatic dynamics simulations on large supramolecular multichromophoric complexes in full atomistic detail. In this framework, the lowest tier of parallelism involves GPU-accelerated electronic structure theory calculations, for which we summarize recent progress in parallelizing the computation and use of electron repulsion integrals (ERIs), which are the major computational bottleneck in both density functional theory (DFT) and time-dependent density functional theory (TDDFT). The topmost tier of parallelism relies on a distributed memory framework, in which we build an exciton model that couples chromophoric units. Combining these multiple levels of parallelism allows access to ground and excited state dynamics for large multichromophoric assemblies. The parallel excitonic framework is in good agreement with much more computationally demanding TDDFT calculations of the full assembly.
Fan, Zheyong; Siro, Topi; Harju, Ari
2012-01-01
In this paper, we develop a highly efficient molecular dynamics code fully implemented on graphics processing units for thermal conductivity calculations using the Green-Kubo formula. We compare two different schemes for force evaluation, a previously used thread-scheme where a single thread is used for one particle and each thread calculates the total force for the corresponding particle, and a new block-scheme where a whole block is used for one particle and each thread in the block calcula...
Really Large Scale Computer Graphic Projection Using Lasers and Laser Substitutes
Rother, Paul
1989-07-01
This paper reflects on past laser projects to display vector scanned computer graphic images onto very large and irregular surfaces. Since the availability of microprocessors and high powered visible lasers, very large scale computer graphics projection have become a reality. Due to the independence from a focusing lens, lasers easily project onto distant and irregular surfaces and have been used for amusement parks, theatrical performances, concert performances, industrial trade shows and dance clubs. Lasers have been used to project onto mountains, buildings, 360° globes, clouds of smoke and water. These methods have proven successful in installations at: Epcot Theme Park in Florida; Stone Mountain Park in Georgia; 1984 Olympics in Los Angeles; hundreds of Corporate trade shows and thousands of musical performances. Using new ColorRayTM technology, the use of costly and fragile lasers is no longer necessary. Utilizing fiber optic technology, the functionality of lasers can be duplicated for new and exciting projection possibilities. The use of ColorRayTM technology has enjoyed worldwide recognition in conjunction with Pink Floyd and George Michaels' world wide tours.
Computational Fluid Dynamics in Combustion
Directory of Open Access Journals (Sweden)
P. J. Paul
2010-10-01
Full Text Available Computational fluid dynamics has reached a stage where flow field in practical situation can be predicted to aid the design and to probe into the fundamental flow physics to understand and resolve the issues in fundamental fluid mechanics. The study examines the computation of reacting flows. After exploring the conservation equations for species and energy, the methods of closing the reaction rate terms in turbulent flow have been examined briefly. Two cases of computation, where combustion-flow interaction plays important role, have been discussed to illustrate the computational aspects and the physical insight that can be gained by the reacting flow computation.Defence Science Journal, 2010, 60(6, pp.577-582, DOI:http://dx.doi.org/10.14429/dsj.60.600
Real-Time Computation of Parameter Fitting and Image Reconstruction Using Graphical Processing Units
Locans, Uldis; Suter, Andreas; Fischer, Jannis; Lustermann, Werner; Dissertori, Gunther; Wang, Qiulin
2016-01-01
In recent years graphical processing units (GPUs) have become a powerful tool in scientific computing. Their potential to speed up highly parallel applications brings the power of high performance computing to a wider range of users. However, programming these devices and integrating their use in existing applications is still a challenging task. In this paper we examined the potential of GPUs for two different applications. The first application, created at Paul Scherrer Institut (PSI), is used for parameter fitting during data analysis of muSR (muon spin rotation, relaxation and resonance) experiments. The second application, developed at ETH, is used for PET (Positron Emission Tomography) image reconstruction and analysis. Applications currently in use were examined to identify parts of the algorithms in need of optimization. Efficient GPU kernels were created in order to allow applications to use a GPU, to speed up the previously identified parts. Benchmarking tests were performed in order to measure the ...
CREW CHIEF: A computer graphics simulation of an aircraft maintenance technician
Aume, Nilss M.
1990-01-01
Approximately 35 percent of the lifetime cost of a military system is spent for maintenance. Excessive repair time is caused by not considering maintenance during design. Problems are usually discovered only after a mock-up has been constructed, when it is too late to make changes. CREW CHIEF will reduce the incidence of such problems by catching design defects in the early design stages. CREW CHIEF is a computer graphic human factors evaluation system interfaced to commercial computer aided design (CAD) systems. It creates a three dimensional man model, either male or female, large or small, with various types of clothing and in several postures. It can perform analyses for physical accessibility, strength capability with tools, visual access, and strength capability for manual materials handling. The designer would produce a drawing on his CAD system and introduce CREW CHIEF in it. CREW CHIEF's analyses would then indicate places where problems could be foreseen and corrected before the design is frozen.
Computational Fluid Dynamics in Ventilation
DEFF Research Database (Denmark)
Nielsen, Peter V.; Allard, Francis; Awbi, Hazim B.;
2008-01-01
Computational Fluid Dynamics in Ventilation Design is a new title in the is a new title in the REHVA guidebook series. The guidebook is written for people who need to use and discuss results based on CFD predictions, and it gives insight into the subject for those who are not used to work with CFD...
Vanezis, P; Blowes, R W; Linney, A D; Tan, A C; Richards, R; Neave, R
1989-07-01
Facial reconstruction has until now been carried out by the sculpting technique. This method involves building a face with clay or other suitable material on to a skull or its cast, taking into account appropriate facial thickness measurements together with information provided by anthropologists such as approximate age, sex, race and other individual idiosyncrasies. A method for facial reconstruction is presented using 3-D computer graphics and is compared with the manual technique. The computer method involves initially digitising a skull using a laser scanner and video camera interfaced to a computer. A face, from a data bank which has previously digitised facial surfaces, is then placed over the skull in the form of a mask and the skin thickness is altered to conform with the underlying skull. The advantage of the computer method is its speed and flexibility. We have shown that the computer method for reconstructing a face is feasible and furthermore has the advantage over the manual technique of speed and flexibility. Nevertheless, the technique is far from perfect. Further facial thickness data needs collecting and the method requires evaluation using both known control skulls and later unknown remains.
Onaral, Banu; And Others
This report describes the development of a Drexel University electrical and computer engineering course on digital filter design that used interactive computing and graphics, and was one of three courses in a senior-level sequence on digital signal processing (DSP). Interactive and digital analysis/design routines and the interconnection of these…
Computational Fluid Dynamics - Applications in Manufacturing Processes
Beninati, Maria Laura; Kathol, Austin; Ziemian, Constance
2012-11-01
A new Computational Fluid Dynamics (CFD) exercise has been developed for the undergraduate introductory fluid mechanics course at Bucknell University. The goal is to develop a computational exercise that students complete which links the manufacturing processes course and the concurrent fluid mechanics course in a way that reinforces the concepts in both. In general, CFD is used as a tool to increase student understanding of the fundamentals in a virtual world. A ``learning factory,'' which is currently in development at Bucknell seeks to use the laboratory as a means to link courses that previously seemed to have little correlation at first glance. A large part of the manufacturing processes course is a project using an injection molding machine. The flow of pressurized molten polyurethane into the mold cavity can also be an example of fluid motion (a jet of liquid hitting a plate) that is applied in manufacturing. The students will run a CFD process that captures this flow using their virtual mold created with a graphics package, such as SolidWorks. The laboratory structure is currently being implemented and analyzed as a part of the ``learning factory''. Lastly, a survey taken before and after the CFD exercise demonstrate a better understanding of both the CFD and manufacturing process.
Discriminating between photorealistic computer graphics and natural images using fractal geometry
Institute of Scientific and Technical Information of China (English)
PAN Feng; CHEN JiongBin; HUANG JiWu
2009-01-01
Rendering technology in computer graphics (CG) Is now capable of producing highly photorealistlc Images, giving rise to the problem of how to identify CG Images from natural images. Some methods were proposed to solve this problem. In this paper, we give a novel method from a new point of view of Image perception. Although the photorealisUc CG images are very similar to natural images, they are surrealistic and smoother than natural images, thus leading to the difference in perception. A part of features are derived from fractal dimension to capture the difference In color perception between CG images and natural Images, and several generalized dimensions are used as the rest features to capture difference in coarseness. The effect of these features is verified by experiments. The average accuracy is over 91.2%.
Edwards, C. L. W.; Meissner, F. T.; Hall, J. B.
1979-01-01
Color computer graphics techniques were investigated as a means of rapidly scanning and interpreting large sets of transient heating data. The data presented were generated to support the conceptual design of a heat-sink thermal protection system (TPS) for a hypersonic research airplane. Color-coded vector and raster displays of the numerical geometry used in the heating calculations were employed to analyze skin thicknesses and surface temperatures of the heat-sink TPS under a variety of trajectory flight profiles. Both vector and raster displays proved to be effective means for rapidly identifying heat-sink mass concentrations, regions of high heating, and potentially adverse thermal gradients. The color-coded (raster) surface displays are a very efficient means for displaying surface-temperature and heating histories, and thereby the more stringent design requirements can quickly be identified. The related hardware and software developments required to implement both the vector and the raster displays for this application are also discussed.
Anquez, Jérémie; Boubekeur, Tamy; Bibin, Lazar; Angelini, Elsa; Bloch, Isabelle
2009-01-01
Potential sanitary effects related to electromagnetic fields exposure raise public concerns, especially for fetuses during pregnancy. Human fetus exposure can only be assessed through simulated dosimetry studies, performed on anthropomorphic models of pregnant women. In this paper, we propose a new methodology to generate a set of detailed utero-fetal unit (UFU) 3D models during the first and third trimesters of pregnancy, based on segmented 3D ultrasound and MRI data. UFU models are built using recent geometry processing methods derived from mesh-based computer graphics techniques and embedded in a synthetic woman body. Nine pregnant woman models have been generated using this approach and validated by obstetricians, for anatomical accuracy and representativeness.
Directory of Open Access Journals (Sweden)
Seulin Ralph
2002-01-01
Full Text Available This work aims at detecting surface defects on reflecting industrial parts. A machine vision system, performing the detection of geometric aspect surface defects, is completely described. The revealing of defects is realized by a particular lighting device. It has been carefully designed to ensure the imaging of defects. The lighting system simplifies a lot the image processing for defect segmentation and so a real-time inspection of reflective products is possible. To bring help in the conception of imaging conditions, a complete simulation is proposed. The simulation, based on computer graphics, enables the rendering of realistic images. Simulation provides here a very efficient way to perform tests compared to the numerous attempts of manual experiments.
uPy: a ubiquitous computer graphics Python API with Biological Modeling Applications
Autin, L.; Johnson, G.; Hake, J.; Olson, A.; Sanner, M.
2015-01-01
In this paper we describe uPy, an extension module for the Python programming language that provides a uniform abstraction of the APIs of several 3D computer graphics programs called hosts, including: Blender, Maya, Cinema4D, and DejaVu. A plugin written with uPy is a unique piece of code that will run in all uPy-supported hosts. We demonstrate the creation of complex plug-ins for molecular/cellular modeling and visualization and discuss how uPy can more generally simplify programming for many types of projects (not solely science applications) intended for multi-host distribution. uPy is available at http://upy.scripps.edu PMID:24806987
Computing the Density Matrix in Electronic Structure Theory on Graphics Processing Units.
Cawkwell, M J; Sanville, E J; Mniszewski, S M; Niklasson, Anders M N
2012-11-13
The self-consistent solution of a Schrödinger-like equation for the density matrix is a critical and computationally demanding step in quantum-based models of interatomic bonding. This step was tackled historically via the diagonalization of the Hamiltonian. We have investigated the performance and accuracy of the second-order spectral projection (SP2) algorithm for the computation of the density matrix via a recursive expansion of the Fermi operator in a series of generalized matrix-matrix multiplications. We demonstrate that owing to its simplicity, the SP2 algorithm [Niklasson, A. M. N. Phys. Rev. B2002, 66, 155115] is exceptionally well suited to implementation on graphics processing units (GPUs). The performance in double and single precision arithmetic of a hybrid GPU/central processing unit (CPU) and full GPU implementation of the SP2 algorithm exceed those of a CPU-only implementation of the SP2 algorithm and traditional matrix diagonalization when the dimensions of the matrices exceed about 2000 × 2000. Padding schemes for arrays allocated in the GPU memory that optimize the performance of the CUBLAS implementations of the level 3 BLAS DGEMM and SGEMM subroutines for generalized matrix-matrix multiplications are described in detail. The analysis of the relative performance of the hybrid CPU/GPU and full GPU implementations indicate that the transfer of arrays between the GPU and CPU constitutes only a small fraction of the total computation time. The errors measured in the self-consistent density matrices computed using the SP2 algorithm are generally smaller than those measured in matrices computed via diagonalization. Furthermore, the errors in the density matrices computed using the SP2 algorithm do not exhibit any dependence of system size, whereas the errors increase linearly with the number of orbitals when diagonalization is employed.
Energy- and cost-efficient lattice-QCD computations using graphics processing units
Energy Technology Data Exchange (ETDEWEB)
Bach, Matthias
2014-07-01
Quarks and gluons are the building blocks of all hadronic matter, like protons and neutrons. Their interaction is described by Quantum Chromodynamics (QCD), a theory under test by large scale experiments like the Large Hadron Collider (LHC) at CERN and in the future at the Facility for Antiproton and Ion Research (FAIR) at GSI. However, perturbative methods can only be applied to QCD for high energies. Studies from first principles are possible via a discretization onto an Euclidean space-time grid. This discretization of QCD is called Lattice QCD (LQCD) and is the only ab-initio option outside of the high-energy regime. LQCD is extremely compute and memory intensive. In particular, it is by definition always bandwidth limited. Thus - despite the complexity of LQCD applications - it led to the development of several specialized compute platforms and influenced the development of others. However, in recent years General-Purpose computation on Graphics Processing Units (GPGPU) came up as a new means for parallel computing. Contrary to machines traditionally used for LQCD, graphics processing units (GPUs) are a massmarket product. This promises advantages in both the pace at which higher-performing hardware becomes available and its price. CL2QCD is an OpenCL based implementation of LQCD using Wilson fermions that was developed within this thesis. It operates on GPUs by all major vendors as well as on central processing units (CPUs). On the AMD Radeon HD 7970 it provides the fastest double-precision D kernel for a single GPU, achieving 120GFLOPS. D - the most compute intensive kernel in LQCD simulations - is commonly used to compare LQCD platforms. This performance is enabled by an in-depth analysis of optimization techniques for bandwidth-limited codes on GPUs. Further, analysis of the communication between GPU and CPU, as well as between multiple GPUs, enables high-performance Krylov space solvers and linear scaling to multiple GPUs within a single system. LQCD
Stork, David G.; Nagy, Gabor
2010-02-01
We explored the working methods of the Italian Baroque master Caravaggio through computer graphics reconstruction of his studio, with special focus on his use of lighting and illumination in The calling of St. Matthew. Although he surely took artistic liberties while constructing this and other works and did not strive to provide a "photographic" rendering of the tableau before him, there are nevertheless numerous visual clues to the likely studio conditions and working methods within the painting: the falloff of brightness along the rear wall, the relative brightness of the faces of figures, and the variation in sharpness of cast shadows (i.e., umbrae and penumbrae). We explored two studio lighting hypotheses: that the primary illumination was local (and hence artificial) and that it was distant solar. We find that the visual evidence can be consistent with local (artificial) illumination if Caravaggio painted his figures separately, adjusting the brightness on each to compensate for the falloff in illumination. Alternatively, the evidence is consistent with solar illumination only if the rear wall had particular reflectance properties, as described by a bi-directional reflectance distribution function, BRDF. (Ours is the first research applying computer graphics to the understanding of artists' praxis that models subtle reflectance properties of surfaces through BRDFs, a technique that may find use in studies of other artists.) A somewhat puzzling visual feature-unnoted in the scholarly literature-is the upward-slanting cast shadow in the upper-right corner of the painting. We found this shadow is naturally consistent with a local illuminant passing through a small window perpendicular to the viewer's line of sight, but could also be consistent with solar illumination if the shadow was due to a slanted, overhanging section of a roof outside the artist's studio. Our results place likely conditions upon any hypotheses concerning Caravaggio's working methods and
Graphic Design for the Computer Age; Visual Communication for all Media.
Hamilton, Edward A.
Because of the rapid pace of today's world, graphic designs which communicate at a glance are needed in all information areas. The essays in this book deal with various aspects of graphic design. These brief essays, each illustrated with graphics, concern the following topics: a short history of visual communication, information design, the merits…
Principles of computational fluid dynamics
Wesseling, Pieter
2001-01-01
The book is aimed at graduate students, researchers, engineers and physicists involved in flow computations. An up-to-date account is given of the present state-of-the-art of numerical methods employed in computational fluid dynamics. The underlying numerical principles are treated with a fair amount of detail, using elementary mathematical analysis. Attention is given to difficulties arising from geometric complexity of the flow domain and of nonuniform structured boundary-fitted grids. Uniform accuracy and efficiency for singular perturbation problems is studied, pointing the way to accurate computation of flows at high Reynolds number. Much attention is given to stability analysis, and useful stability conditions are provided, some of them new, for many numerical schemes used in practice. Unified methods for compressible and incompressible flows are discussed. Numerical analysis of the shallow-water equations is included. The theory of hyperbolic conservation laws is treated. Godunov's order barrier and ho...
Graphics processing unit (GPU)-based computation of heat conduction in thermally anisotropic solids
Nahas, C. A.; Balasubramaniam, Krishnan; Rajagopal, Prabhu
2013-01-01
Numerical modeling of anisotropic media is a computationally intensive task since it brings additional complexity to the field problem in such a way that the physical properties are different in different directions. Largely used in the aerospace industry because of their lightweight nature, composite materials are a very good example of thermally anisotropic media. With advancements in video gaming technology, parallel processors are much cheaper today and accessibility to higher-end graphical processing devices has increased dramatically over the past couple of years. Since these massively parallel GPUs are very good in handling floating point arithmetic, they provide a new platform for engineers and scientists to accelerate their numerical models using commodity hardware. In this paper we implement a parallel finite difference model of thermal diffusion through anisotropic media using the NVIDIA CUDA (Compute Unified device Architecture). We use the NVIDIA GeForce GTX 560 Ti as our primary computing device which consists of 384 CUDA cores clocked at 1645 MHz with a standard desktop pc as the host platform. We compare the results from standard CPU implementation for its accuracy and speed and draw implications for simulation using the GPU paradigm.
Computer Graphics as an Instructional Aid in an Introductory Differential Calculus Course
Directory of Open Access Journals (Sweden)
Tapan Kumar Tiwari
2007-02-01
Full Text Available Mathematicians in general claim that the Computer Algebra Systems (CAS provide an excellent tool for illustrating calculus concepts. They caution, however, against heavy dependency on the CAS for all computational purposes without the mastery of the procedures involved. This study examined the effect of using the graphical and numerical capabilities of Mathematica as a supplemental instructional tool in enhancing the conceptual knowledge and problem solving abilities of students in a differential calculus course. Topics of differential calculus were introduced by the traditional lecture method to both the control and experimental groups comprised of students enrolled in two sections of the Business and Life Sciences I course. Mathematica was used only by the students of the experimental group to reinforce and illustrate the concepts developed by the traditional method. A content analysis was conducted using the qualitative data obtained from students’ explanations of the derivative of a function. The quantitative data, the students’ test scores, were analyzed using ANCOVA. The results showed that students in the experimental group scored higher than students in the control group on both the conceptual and the computational parts of the examination. The qualitative analysis results revealed that, compared to the control group, a higher percentage of students in the experimental group had a better understanding of the derivative.
Vucinic, Dean; Deen, Danny; Oanta, Emil; Batarilo, Zvonimir; Lacor, Chris
This paper focuses on visualization and manipulation of graphical content in distributed network environments. The developed graphical middleware and 3D desktop prototypes were specialized for situational awareness. This research was done in the LArge Scale COllaborative decision support Technology (LASCOT) project, which explored and combined software technologies to support human-centred decision support system for crisis management (earthquake, tsunami, flooding, airplane or oil-tanker incidents, chemical, radio-active or other pollutants spreading, etc.). The performed state-of-the-art review did not identify any publicly available large scale distributed application of this kind. Existing proprietary solutions rely on the conventional technologies and 2D representations. Our challenge was to apply the "latest" available technologies, such Java3D, X3D and SOAP, compatible with average computer graphics hardware. The selected technologies are integrated and we demonstrate: the flow of data, which originates from heterogeneous data sources; interoperability across different operating systems and 3D visual representations to enhance the end-users interactions.
Choi, Sunghwan; Kwon, Oh-Kyoung; Kim, Jaewook; Kim, Woo Youn
2016-09-15
We investigated the performance of heterogeneous computing with graphics processing units (GPUs) and many integrated core (MIC) with 20 CPU cores (20×CPU). As a practical example toward large scale electronic structure calculations using grid-based methods, we evaluated the Hartree potentials of silver nanoparticles with various sizes (3.1, 3.7, 4.9, 6.1, and 6.9 nm) via a direct integral method supported by the sinc basis set. The so-called work stealing scheduler was used for efficient heterogeneous computing via the balanced dynamic distribution of workloads between all processors on a given architecture without any prior information on their individual performances. 20×CPU + 1GPU was up to ∼1.5 and ∼3.1 times faster than 1GPU and 20×CPU, respectively. 20×CPU + 2GPU was ∼4.3 times faster than 20×CPU. The performance enhancement by CPU + MIC was considerably lower than expected because of the large initialization overhead of MIC, although its theoretical performance is similar with that of CPU + GPU. © 2016 Wiley Periodicals, Inc.
Parietal neural prosthetic control of a computer cursor in a graphical-user-interface task
Revechkis, Boris; Aflalo, Tyson NS; Kellis, Spencer; Pouratian, Nader; Andersen, Richard A.
2014-12-01
Objective. To date, the majority of Brain-Machine Interfaces have been used to perform simple tasks with sequences of individual targets in otherwise blank environments. In this study we developed a more practical and clinically relevant task that approximated modern computers and graphical user interfaces (GUIs). This task could be problematic given the known sensitivity of areas typically used for BMIs to visual stimuli, eye movements, decision-making, and attentional control. Consequently, we sought to assess the effect of a complex, GUI-like task on the quality of neural decoding. Approach. A male rhesus macaque monkey was implanted with two 96-channel electrode arrays in area 5d of the superior parietal lobule. The animal was trained to perform a GUI-like ‘Face in a Crowd’ task on a computer screen that required selecting one cued, icon-like, face image from a group of alternatives (the ‘Crowd’) using a neurally controlled cursor. We assessed whether the crowd affected decodes of intended cursor movements by comparing it to a ‘Crowd Off’ condition in which only the matching target appeared without alternatives. We also examined if training a neural decoder with the Crowd On rather than Off had any effect on subsequent decode quality. Main results. Despite the additional demands of working with the Crowd On, the animal was able to robustly perform the task under Brain Control. The presence of the crowd did not itself affect decode quality. Training the decoder with the Crowd On relative to Off had no negative influence on subsequent decoding performance. Additionally, the subject was able to gaze around freely without influencing cursor position. Significance. Our results demonstrate that area 5d recordings can be used for decoding in a complex, GUI-like task with free gaze. Thus, this area is a promising source of signals for neural prosthetics that utilize computing devices with GUI interfaces, e.g. personal computers, mobile devices, and tablet
Jakubczyk, D.; Migacz, S.; Derkachov, G.; Woźniak, M.; Archer, J.; Kolwas, K.
2016-09-01
We report on the first application of the graphics processing units (GPUs) accelerated computing technology to improve performance of numerical methods used for the optical characterization of evaporating microdroplets. Single microdroplets of various liquids with different volatility and molecular weight (glycerine, glycols, water, etc.), as well as mixtures of liquids and diverse suspensions evaporate inside the electrodynamic trap under the chosen temperature and composition of atmosphere. The series of scattering patterns recorded from the evaporating microdroplets are processed by fitting complete Mie theory predictions with gradientless lookup table method. We showed that computations on GPUs can be effectively applied to inverse scattering problems. In particular, our technique accelerated calculations of the Mie scattering theory on a single-core processor in a Matlab environment over 800 times and almost 100 times comparing to the corresponding code in C language. Additionally, we overcame problems of the time-consuming data post-processing when some of the parameters (particularly the refractive index) of an investigated liquid are uncertain. Our program allows us to track the parameters characterizing the evaporating droplet nearly simultaneously with the progress of evaporation.
Exploring Graphics Processing Unit (GPU Resource Sharing Efficiency for High Performance Computing
Directory of Open Access Journals (Sweden)
Teng Li
2013-11-01
Full Text Available The increasing incorporation of Graphics Processing Units (GPUs as accelerators has been one of the forefront High Performance Computing (HPC trends and provides unprecedented performance; however, the prevalent adoption of the Single-Program Multiple-Data (SPMD programming model brings with it challenges of resource underutilization. In other words, under SPMD, every CPU needs GPU capability available to it. However, since CPUs generally outnumber GPUs, the asymmetric resource distribution gives rise to overall computing resource underutilization. In this paper, we propose to efficiently share the GPU under SPMD and formally define a series of GPU sharing scenarios. We provide performance-modeling analysis for each sharing scenario with accurate experimentation validation. With the modeling basis, we further conduct experimental studies to explore potential GPU sharing efficiency improvements from multiple perspectives. Both further theoretical and experimental GPU sharing performance analysis and results are presented. Our results not only demonstrate the significant performance gain for SPMD programs with the proposed efficient GPU sharing, but also the further improved sharing efficiency with the optimization techniques based on our accurate modeling.
Soliton dynamics in computational anatomy.
Holm, Darryl D; Ratnanather, J Tilak; Trouvé, Alain; Younes, Laurent
2004-01-01
Computational anatomy (CA) has introduced the idea of anatomical structures being transformed by geodesic deformations on groups of diffeomorphisms. Among these geometric structures, landmarks and image outlines in CA are shown to be singular solutions of a partial differential equation that is called the geodesic EPDiff equation. A recently discovered momentum map for singular solutions of EPDiff yields their canonical Hamiltonian formulation, which in turn provides a complete parameterization of the landmarks by their canonical positions and momenta. The momentum map provides an isomorphism between landmarks (and outlines) for images and singular soliton solutions of the EPDiff equation. This isomorphism suggests a new dynamical paradigm for CA, as well as new data representation.
Tsuchimoto, Masashi; Tanimura, Yoshitaka
2015-08-11
A system with many energy states coupled to a harmonic oscillator bath is considered. To study quantum non-Markovian system-bath dynamics numerically rigorously and nonperturbatively, we developed a computer code for the reduced hierarchy equations of motion (HEOM) for a graphics processor unit (GPU) that can treat the system as large as 4096 energy states. The code employs a Padé spectrum decomposition (PSD) for a construction of HEOM and the exponential integrators. Dynamics of a quantum spin glass system are studied by calculating the free induction decay signal for the cases of 3 × 2 to 3 × 4 triangular lattices with antiferromagnetic interactions. We found that spins relax faster at lower temperature due to transitions through a quantum coherent state, as represented by the off-diagonal elements of the reduced density matrix, while it has been known that the spins relax slower due to suppression of thermal activation in a classical case. The decay of the spins are qualitatively similar regardless of the lattice sizes. The pathway of spin relaxation is analyzed under a sudden temperature drop condition. The Compute Unified Device Architecture (CUDA) based source code used in the present calculations is provided as Supporting Information .
Unzueta, Caridad H.; Barbetta, Patricia M.
2012-01-01
A multiple baseline design investigated the effects of computer graphic organizers on the persuasive composition writing skills of four Hispanic students with specific learning disabilities. Participants reviewed the elements of persuasive writing and then developed compositions using a word processing program. Baseline planning was done with a…
Unzueta, Caridad H.; Barbetta, Patricia M.
2012-01-01
A multiple baseline design investigated the effects of computer graphic organizers on the persuasive composition writing skills of four Hispanic students with specific learning disabilities. Participants reviewed the elements of persuasive writing and then developed compositions using a word processing program. Baseline planning was done with a…
Evolutionary computation for dynamic optimization problems
Yao, Xin
2013-01-01
This book provides a compilation on the state-of-the-art and recent advances of evolutionary computation for dynamic optimization problems. The motivation for this book arises from the fact that many real-world optimization problems and engineering systems are subject to dynamic environments, where changes occur over time. Key issues for addressing dynamic optimization problems in evolutionary computation, including fundamentals, algorithm design, theoretical analysis, and real-world applications, are presented. "Evolutionary Computation for Dynamic Optimization Problems" is a valuable reference to scientists, researchers, professionals and students in the field of engineering and science, particularly in the areas of computational intelligence, nature- and bio-inspired computing, and evolutionary computation.
Giorgino, Toni; Laio, Alessandro; Rodriguez, Alex
2017-08-01
Molecular dynamics (MD) simulations allow the exploration of the phase space of biopolymers through the integration of equations of motion of their constituent atoms. The analysis of MD trajectories often relies on the choice of collective variables (CVs) along which the dynamics of the system is projected. We developed a graphical user interface (GUI) for facilitating the interactive choice of the appropriate CVs. The GUI allows: defining interactively new CVs; partitioning the configurations into microstates characterized by similar values of the CVs; calculating the free energies of the microstates for both unbiased and biased (metadynamics) simulations; clustering the microstates in kinetic basins; visualizing the free energy landscape as a function of a subset of the CVs used for the analysis. A simple mouse click allows one to quickly inspect structures corresponding to specific points in the landscape.
Next Generation Sequence Analysis and Computational Genomics Using Graphical Pipeline Workflows
Directory of Open Access Journals (Sweden)
Marquis P. Vawter
2012-08-01
Full Text Available Whole-genome and exome sequencing have already proven to be essential and powerful methods to identify genes responsible for simple Mendelian inherited disorders. These methods can be applied to complex disorders as well, and have been adopted as one of the current mainstream approaches in population genetics. These achievements have been made possible by next generation sequencing (NGS technologies, which require substantial bioinformatics resources to analyze the dense and complex sequence data. The huge analytical burden of data from genome sequencing might be seen as a bottleneck slowing the publication of NGS papers at this time, especially in psychiatric genetics. We review the existing methods for processing NGS data, to place into context the rationale for the design of a computational resource. We describe our method, the Graphical Pipeline for Computational Genomics (GPCG, to perform the computational steps required to analyze NGS data. The GPCG implements flexible workflows for basic sequence alignment, sequence data quality control, single nucleotide polymorphism analysis, copy number variant identification, annotation, and visualization of results. These workflows cover all the analytical steps required for NGS data, from processing the raw reads to variant calling and annotation. The current version of the pipeline is freely available at http://pipeline.loni.ucla.edu. These applications of NGS analysis may gain clinical utility in the near future (e.g., identifying miRNA signatures in diseases when the bioinformatics approach is made feasible. Taken together, the annotation tools and strategies that have been developed to retrieve information and test hypotheses about the functional role of variants present in the human genome will help to pinpoint the genetic risk factors for psychiatric disorders.
Next generation sequence analysis and computational genomics using graphical pipeline workflows.
Torri, Federica; Dinov, Ivo D; Zamanyan, Alen; Hobel, Sam; Genco, Alex; Petrosyan, Petros; Clark, Andrew P; Liu, Zhizhong; Eggert, Paul; Pierce, Jonathan; Knowles, James A; Ames, Joseph; Kesselman, Carl; Toga, Arthur W; Potkin, Steven G; Vawter, Marquis P; Macciardi, Fabio
2012-08-30
Whole-genome and exome sequencing have already proven to be essential and powerful methods to identify genes responsible for simple Mendelian inherited disorders. These methods can be applied to complex disorders as well, and have been adopted as one of the current mainstream approaches in population genetics. These achievements have been made possible by next generation sequencing (NGS) technologies, which require substantial bioinformatics resources to analyze the dense and complex sequence data. The huge analytical burden of data from genome sequencing might be seen as a bottleneck slowing the publication of NGS papers at this time, especially in psychiatric genetics. We review the existing methods for processing NGS data, to place into context the rationale for the design of a computational resource. We describe our method, the Graphical Pipeline for Computational Genomics (GPCG), to perform the computational steps required to analyze NGS data. The GPCG implements flexible workflows for basic sequence alignment, sequence data quality control, single nucleotide polymorphism analysis, copy number variant identification, annotation, and visualization of results. These workflows cover all the analytical steps required for NGS data, from processing the raw reads to variant calling and annotation. The current version of the pipeline is freely available at http://pipeline.loni.ucla.edu. These applications of NGS analysis may gain clinical utility in the near future (e.g., identifying miRNA signatures in diseases) when the bioinformatics approach is made feasible. Taken together, the annotation tools and strategies that have been developed to retrieve information and test hypotheses about the functional role of variants present in the human genome will help to pinpoint the genetic risk factors for psychiatric disorders.
Energy Technology Data Exchange (ETDEWEB)
Hayashi, Nakamasa; Kurimoto, Masanori; Hirashima, Yutaka; Ikeda, Hiroaki; Shibata, Takashi; Tomita, Takahiro; Endo, Shunro [Toyama Medical and Pharmaceutical Univ. (Japan)
2001-07-01
The efficacy of a neurosurgical navigation system using three-dimensional composite computer graphics (CGs) of magnetic resonance (MR) and computed tomography (CT) images was evaluated in skull base surgery. Three-point transformation was used for integration of MR and CT images. MR and CT image data were obtained with three skin markers placed on the patient's scalp. Volume-rendering manipulations of the data produced three-dimensional CGs of the scalp, brain, and lesions from the MR images, and the scalp and skull from the CT. Composite CGs of the scalp, skull, brain, and lesion were created by registering the three markers on the three-dimensional rendered scalp images obtained from MR imaging and CT in the system. This system was used for 14 patients with skull base lesions. Three-point transformation using three-dimensional CGs was easily performed for multimodal registration. Simulation of surgical procedures on composite CGs aided in comprehension of the skull base anatomy and selection of the optimal approaches. Intraoperative navigation aided in determination of actual spatial position in the skull base and the optimal trajectory to the tumor during surgical procedures. (author)
Energy Technology Data Exchange (ETDEWEB)
Cahn, D.F.; Murano, C.V.
1980-05-01
An interactive computer graphical display program was developed as an aid to user visualization and manipulation of hierarchically structured data systems such as thesauri. In the present configuration, a thesaurus term and its primary and secondary conceptual neighbors are presented to the user in tree graph form on a CRT; the user then designates, via light pen or keyboard, any of the neighbors as the next term of interest and receives a new display centered on this term. By successive specification of broader, narrower, and related terms, the user can course rapidly through the thesaurus space and refine his search file. At any stage, he deals with a term-centered, conceptually meaningful picture of a localized portion of the thesaurus, and is freed from the artificial difficulties of handling the traditional alphabetized thesaurus. Intentional limitation of the associative range of each display frame, and the use of color, case, and interconnecting vectors to encode relationships among terms, enhance interpretability of the display. Facile movement through the term space, provided by interactive computation, allows the display to remain simple, and is an essential element of the system. 3 figures.
Computational methods for fluid dynamics
Ferziger, Joel H
2002-01-01
In its 3rd revised and extended edition the book offers an overview of the techniques used to solve problems in fluid mechanics on computers and describes in detail those most often used in practice. Included are advanced methods in computational fluid dynamics, like direct and large-eddy simulation of turbulence, multigrid methods, parallel computing, moving grids, structured, block-structured and unstructured boundary-fitted grids, free surface flows. The 3rd edition contains a new section dealing with grid quality and an extended description of discretization methods. The book shows common roots and basic principles for many different methods. The book also contains a great deal of practical advice for code developers and users, it is designed to be equally useful to beginners and experts. The issues of numerical accuracy, estimation and reduction of numerical errors are dealt with in detail, with many examples. A full-feature user-friendly demo-version of a commercial CFD software has been added, which ca...
Matlab在计算机图形学中的应用%Application of Matlab in the Computer Graphics
Institute of Scientific and Technical Information of China (English)
胡建平; 李鹏松
2013-01-01
探讨在计算机图形学中如何使用Matlab生成基本图形元素，绘制三角网格模型，以及实现三维几何变换等基本的图形学算法。从中可以看出使用Matlab编写图形学程序简单易行，可以用其作为计算机图形学的程序开发工具，使传统的复杂编程语言变成可视化。%This paper discusses how to apply Matlab to generate some basic graphical elements,render triangu-lar meshes,and implement 3D geometrical transformations in the experiment teaching of computer graphics. It demonstrates that Matlab is easy to be used to implement the programs of computer graphics and can be used as an alternative programming tool in the experiment teaching of computer graphics. This can not only set students free from the traditional complicated visual programming languages but also stimulate the interests of students,which can improve the efficiency of teaching and studying greatly.
3D animation of facial plastic surgery based on computer graphics
Zhang, Zonghua; Zhao, Yan
2013-12-01
More and more people, especial women, are getting desired to be more beautiful than ever. To some extent, it becomes true because the plastic surgery of face was capable in the early 20th and even earlier as doctors just dealing with war injures of face. However, the effect of post-operation is not always satisfying since no animation could be seen by the patients beforehand. In this paper, by combining plastic surgery of face and computer graphics, a novel method of simulated appearance of post-operation will be given to demonstrate the modified face from different viewpoints. The 3D human face data are obtained by using 3D fringe pattern imaging systems and CT imaging systems and then converted into STL (STereo Lithography) file format. STL file is made up of small 3D triangular primitives. The triangular mesh can be reconstructed by using hash function. Top triangular meshes in depth out of numbers of triangles must be picked up by ray-casting technique. Mesh deformation is based on the front triangular mesh in the process of simulation, which deforms interest area instead of control points. Experiments on face model show that the proposed 3D animation facial plastic surgery can effectively demonstrate the simulated appearance of post-operation.
Stork, David G.; Furuichi, Yasuo
2011-03-01
David Hockney has argued that the right hand of the disciple, thrust to the rear in Caravaggio's Supper at Emmaus (1606), is anomalously large as a result of the artist refocusing a putative secret lens-based optical projector and tracing the image it projected onto his canvas. We show through rigorous optical analysis that to achieve such an anomalously large hand image, Caravaggio would have needed to make extremely large, conspicuous and implausible alterations to his studio setup, moving both his purported lens and his canvas nearly two meters between "exposing" the disciple's left hand and then his right hand. Such major disruptions to his studio would have impeded -not aided- Caravaggio in his work. Our optical analysis quantifies these problems and our computer graphics reconstruction of Caravaggio's studio illustrates these problems. In this way we conclude that Caravaggio did not use optical projections in the way claimed by Hockney, but instead most likely set the sizes of these hands "by eye" for artistic reasons.
Fast computation of MadGraph amplitudes on graphics processing unit (GPU)
Hagiwara, K; Li, Q; Okamura, N; Stelzer, T
2013-01-01
Continuing our previous studies on QED and QCD processes, we use the graphics processing unit (GPU) for fast calculations of helicity amplitudes for general Standard Model (SM) processes. Additional HEGET codes to handle all SM interactions are introduced, as well assthe program MG2CUDA that converts arbitrary MadGraph generated HELAS amplitudess(FORTRAN) into HEGET codes in CUDA. We test all the codes by comparing amplitudes and cross sections for multi-jet srocesses at the LHC associated with production of single and double weak bosonss a top-quark pair, Higgs boson plus a weak boson or a top-quark pair, and multisle Higgs bosons via weak-boson fusion, where all the heavy particles are allowes to decay into light quarks and leptons with full spin correlations. All the helicity amplitudes computed by HEGET are found to agree with those comsuted by HELAS within the expected numerical accuracy, and the cross sections obsained by gBASES, a GPU version of the Monte Carlo integration program, agree wish those obt...
Nonlinear dynamics as an engine of computation.
Kia, Behnam; Lindner, John F; Ditto, William L
2017-03-06
Control of chaos teaches that control theory can tame the complex, random-like behaviour of chaotic systems. This alliance between control methods and physics-cybernetical physics-opens the door to many applications, including dynamics-based computing. In this article, we introduce nonlinear dynamics and its rich, sometimes chaotic behaviour as an engine of computation. We review our work that has demonstrated how to compute using nonlinear dynamics. Furthermore, we investigate the interrelationship between invariant measures of a dynamical system and its computing power to strengthen the bridge between physics and computation.This article is part of the themed issue 'Horizons of cybernetical physics'.
Nonlinear dynamics as an engine of computation
Kia, Behnam; Lindner, John F.; Ditto, William L.
2017-03-01
Control of chaos teaches that control theory can tame the complex, random-like behaviour of chaotic systems. This alliance between control methods and physics-cybernetical physics-opens the door to many applications, including dynamics-based computing. In this article, we introduce nonlinear dynamics and its rich, sometimes chaotic behaviour as an engine of computation. We review our work that has demonstrated how to compute using nonlinear dynamics. Furthermore, we investigate the interrelationship between invariant measures of a dynamical system and its computing power to strengthen the bridge between physics and computation. This article is part of the themed issue 'Horizons of cybernetical physics'.
Computer Modeling of Real-Time Dynamic Lighting
Maida, James C.; Pace, J.; Novak, J.; Russo, Dane M. (Technical Monitor)
2000-01-01
Space Station tasks involve procedures that are very complex and highly dependent on the availability of visual information. In many situations, cameras are used as tools to help overcome the visual and physical restrictions associated with space flight. However, these cameras are effected by the dynamic lighting conditions of space. Training for these is conditions is necessary. The current project builds on the findings of an earlier NRA funded project, which revealed improved performance by humans when trained with computer graphics and lighting effects such as shadows and glare.
计算机图形学的应用及研究%Application and Research Fronts of Computer Graphics
Institute of Scientific and Technical Information of China (English)
滑瑞朋
2012-01-01
Computer graphics is a science that transforms 2D or 3D graphics into grid forms of computer monitors with the help of mathematical algorithm.It has been applied in the fields of realistic graphics,visualization of scientific computing,virtual reality,computer art and design,computer animation and intelligent CAD.The development history,application and prospects are introduced.%计算机图形学是一种使用数学算法将二维或三维图形转化为计算机显示器的栅格形式的科学。计算机图形学的应用已经深入到真实感图形、科学计算可视化、虚拟现实、计算机美术与设计、计算机动画艺术、智能CAD等领域。介绍了计算机图形学的发展历史、应用和发展前景。
Graphic engine resource management
Bautin, Mikhail; Dwarakinath, Ashok; Chiueh, Tzi-cker
2008-01-01
Modern consumer-grade 3D graphic cards boast a computation/memory resource that can easily rival or even exceed that of standard desktop PCs. Although these cards are mainly designed for 3D gaming applications, their enormous computational power has attracted developers to port an increasing number of scientific computation programs to these cards, including matrix computation, collision detection, cryptography, database sorting, etc. As more and more applications run on 3D graphic cards, there is a need to allocate the computation/memory resource on these cards among the sharing applications more fairly and efficiently. In this paper, we describe the design, implementation and evaluation of a Graphic Processing Unit (GPU) scheduler based on Deficit Round Robin scheduling that successfully allocates to every process an equal share of the GPU time regardless of their demand. This scheduler, called GERM, estimates the execution time of each GPU command group based on dynamically collected statistics, and controls each process's GPU command production rate through its CPU scheduling priority. Measurements on the first GERM prototype show that this approach can keep the maximal GPU time consumption difference among concurrent GPU processes consistently below 5% for a variety of application mixes.
Dynamics of Information as Natural Computation
Directory of Open Access Journals (Sweden)
Gordana Dodig Crnkovic
2011-08-01
Full Text Available Processes considered rendering information dynamics have been studied, among others in: questions and answers, observations, communication, learning, belief revision, logical inference, game-theoretic interactions and computation. This article will put the computational approaches into a broader context of natural computation, where information dynamics is not only found in human communication and computational machinery but also in the entire nature. Information is understood as representing the world (reality as an informational web for a cognizing agent, while information dynamics (information processing, computation realizes physical laws through which all the changes of informational structures unfold. Computation as it appears in the natural world is more general than the human process of calculation modeled by the Turing machine. Natural computing is epitomized through the interactions of concurrent, in general asynchronous computational processes which are adequately represented by what Abramsky names “the second generation models of computation” [1] which we argue to be the most general representation of information dynamics.
The Effectiveness of an Interactive 3-Dimensional Computer Graphics Model for Medical Education
Konishi, Takeshi; Tamura, Yoko; Moriguchi, Hiroki
2012-01-01
Background Medical students often have difficulty achieving a conceptual understanding of 3-dimensional (3D) anatomy, such as bone alignment, muscles, and complex movements, from 2-dimensional (2D) images. To this end, animated and interactive 3-dimensional computer graphics (3DCG) can provide better visual information to users. In medical fields, research on the advantages of 3DCG in medical education is relatively new. Objective To determine the educational effectiveness of interactive 3DCG. Methods We divided 100 participants (27 men, mean (SD) age 17.9 (0.6) years, and 73 women, mean (SD) age 18.1 (1.1) years) from the Health Sciences University of Mongolia (HSUM) into 3DCG (n = 50) and textbook-only (control) (n = 50) groups. The control group used a textbook and 2D images, while the 3DCG group was trained to use the interactive 3DCG shoulder model in addition to a textbook. We conducted a questionnaire survey via an encrypted satellite network between HSUM and Tokushima University. The questionnaire was scored on a 5-point Likert scale from strongly disagree (score 1) to strongly agree (score 5). Results Interactive 3DCG was effective in undergraduate medical education. Specifically, there was a significant difference in mean (SD) scores between the 3DCG and control groups in their response to questionnaire items regarding content (4.26 (0.69) vs 3.85 (0.68), P = .001) and teaching methods (4.33 (0.65) vs 3.74 (0.79), P < .001), but no significant difference in the Web category. Participants also provided meaningful comments on the advantages of interactive 3DCG. Conclusions Interactive 3DCG materials have positive effects on medical education when properly integrated into conventional education. In particular, our results suggest that interactive 3DCG is more efficient than textbooks alone in medical education and can motivate students to understand complex anatomical structures. PMID:23611759
Model dynamics for quantum computing
Tabakin, Frank
2017-08-01
A model master equation suitable for quantum computing dynamics is presented. In an ideal quantum computer (QC), a system of qubits evolves in time unitarily and, by virtue of their entanglement, interfere quantum mechanically to solve otherwise intractable problems. In the real situation, a QC is subject to decoherence and attenuation effects due to interaction with an environment and with possible short-term random disturbances and gate deficiencies. The stability of a QC under such attacks is a key issue for the development of realistic devices. We assume that the influence of the environment can be incorporated by a master equation that includes unitary evolution with gates, supplemented by a Lindblad term. Lindblad operators of various types are explored; namely, steady, pulsed, gate friction, and measurement operators. In the master equation, we use the Lindblad term to describe short time intrusions by random Lindblad pulses. The phenomenological master equation is then extended to include a nonlinear Beretta term that describes the evolution of a closed system with increasing entropy. An external Bath environment is stipulated by a fixed temperature in two different ways. Here we explore the case of a simple one-qubit system in preparation for generalization to multi-qubit, qutrit and hybrid qubit-qutrit systems. This model master equation can be used to test the stability of memory and the efficacy of quantum gates. The properties of such hybrid master equations are explored, with emphasis on the role of thermal equilibrium and entropy constraints. Several significant properties of time-dependent qubit evolution are revealed by this simple study.
2015-04-01
Graphical User Interface ( GUI ) Design for Ballistic Research Laboratory–Computer-Aided Design’s (BRL–CAD’s) Geometry Difference (GDiff) Tool...to the originator. Army Research Laboratory Aberdeen Proving Ground, MD 21005 ARL-CR-0756 April 2015 Graphical User Interface ( GUI ...2015 2. REPORT TYPE Contractor Report 3. DATES COVERED (From - To) 06/2014–08/2014 4. TITLE AND SUBTITLE Graphical User Interface ( GUI ) Design for
Efficient molecular dynamics simulations with many-body potentials on graphics processing units
Fan, Zheyong; Chen, Wei; Vierimaa, Ville; Harju, Ari
2017-09-01
Graphics processing units have been extensively used to accelerate classical molecular dynamics simulations. However, there is much less progress on the acceleration of force evaluations for many-body potentials compared to pairwise ones. In the conventional force evaluation algorithm for many-body potentials, the force, virial stress, and heat current for a given atom are accumulated within different loops, which could result in write conflict between different threads in a CUDA kernel. In this work, we provide a new force evaluation algorithm, which is based on an explicit pairwise force expression for many-body potentials derived recently (Fan et al., 2015). In our algorithm, the force, virial stress, and heat current for a given atom can be accumulated within a single thread and is free of write conflicts. We discuss the formulations and algorithms and evaluate their performance. A new open-source code, GPUMD, is developed based on the proposed formulations. For the Tersoff many-body potential, the double precision performance of GPUMD using a Tesla K40 card is equivalent to that of the LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) molecular dynamics code running with about 100 CPU cores (Intel Xeon CPU X5670 @ 2.93 GHz).
Freiberger, Manuel; Egger, Herbert; Liebmann, Manfred; Scharfetter, Hermann
2011-11-01
Image reconstruction in fluorescence optical tomography is a three-dimensional nonlinear ill-posed problem governed by a system of partial differential equations. In this paper we demonstrate that a combination of state of the art numerical algorithms and a careful hardware optimized implementation allows to solve this large-scale inverse problem in a few seconds on standard desktop PCs with modern graphics hardware. In particular, we present methods to solve not only the forward but also the non-linear inverse problem by massively parallel programming on graphics processors. A comparison of optimized CPU and GPU implementations shows that the reconstruction can be accelerated by factors of about 15 through the use of the graphics hardware without compromising the accuracy in the reconstructed images.
3D game engine design a practical approach to real-time computer graphics
Eberly, David H
2006-01-01
A major revision of the international bestseller on game programming!Graphics hardware has evolved enormously in the last decade. Hardware can now be directly controlled through techniques such as shader programming, which requires an entirely new thought process of a programmer. 3D Game Engine Design, Second Edition shows step-by-step how to make a shader-based graphics engine and how to tame the new technology. Much new material has been added, including more than twice the coverage of the essential techniques of scene graph management, as well as new methods for manag
Security Dynamics of Cloud Computing
Khaled M. Khan
2009-01-01
This paper explores various dimensions of cloud computing security. It argues that security concerns of cloud computing need to be addressed from the perspective of individual stakeholder. Security focuses of cloud computing are essentially different in terms of its characteristics and business model. Conventional way of viewing as well as addressing security such as ‘bolting-in’ on the top of cloud computing may not work well. The paper attempts to portray the security spectrum necessary for...
Implementing a low-latency parallel graphic equalizer with heterogeneous computing
Norilo, Vesa; Verstraelen, Math; Valimaki, Vesa; Svensson, Peter; Kristiansen, Ulf
2015-01-01
This paper describes the implementation of a recently introduced parallel graphic equalizer (PGE) in a heterogeneous way. The control and audio signal processing parts of the PGE are distributed to a PC and to a signal processor, of WaveCore architecture, respectively. This arrangement is particular
Implementing a low-latency parallel graphic equalizer with heterogeneous computing
Norilo, Vesa; Verstraelen, Martinus Johannes Wilhelmina; Valimaki, Vesa; Svensson, Peter; Kristiansen, Ulf
2015-01-01
This paper describes the implementation of a recently introduced parallel graphic equalizer (PGE) in a heterogeneous way. The control and audio signal processing parts of the PGE are distributed to a PC and to a signal processor, of WaveCore architecture, respectively. This arrangement is
Naaz, Farah; Chariker, Julia H.; Pani, John R.
2014-01-01
A study was conducted to test the hypothesis that instruction with graphically integrated representations of whole and sectional neuroanatomy is especially effective for learning to recognize neural structures in sectional imagery (such as magnetic resonance imaging [MRI]). Neuroanatomy was taught to two groups of participants using computer…
Text, Graphics, and Multimedia Materials Employed in Learning a Computer-Based Procedural Task
Coffindaffer, Kari Christine Carlson
2010-01-01
The present research study investigated the interaction of graphic design students with different forms of software training materials. Four versions of the procedural task instructions were developed (A) Traditional Textbook with Still Images, (B) Modified Text with Integrated Still Images, (C) Onscreen Modified Text with Silent Onscreen Video…
Arvo, James
1991-01-01
Graphics Gems II is a collection of articles shared by a diverse group of people that reflect ideas and approaches in graphics programming which can benefit other computer graphics programmers.This volume presents techniques for doing well-known graphics operations faster or easier. The book contains chapters devoted to topics on two-dimensional and three-dimensional geometry and algorithms, image processing, frame buffer techniques, and ray tracing techniques. The radiosity approach, matrix techniques, and numerical and programming techniques are likewise discussed.Graphics artists and comput
Fluid dynamics theory, computation, and numerical simulation
Pozrikidis, C
2001-01-01
Fluid Dynamics Theory, Computation, and Numerical Simulation is the only available book that extends the classical field of fluid dynamics into the realm of scientific computing in a way that is both comprehensive and accessible to the beginner The theory of fluid dynamics, and the implementation of solution procedures into numerical algorithms, are discussed hand-in-hand and with reference to computer programming This book is an accessible introduction to theoretical and computational fluid dynamics (CFD), written from a modern perspective that unifies theory and numerical practice There are several additions and subject expansions in the Second Edition of Fluid Dynamics, including new Matlab and FORTRAN codes Two distinguishing features of the discourse are solution procedures and algorithms are developed immediately after problem formulations are presented, and numerical methods are introduced on a need-to-know basis and in increasing order of difficulty Matlab codes are presented and discussed for a broad...
Fluid Dynamics Theory, Computation, and Numerical Simulation
Pozrikidis, Constantine
2009-01-01
Fluid Dynamics: Theory, Computation, and Numerical Simulation is the only available book that extends the classical field of fluid dynamics into the realm of scientific computing in a way that is both comprehensive and accessible to the beginner. The theory of fluid dynamics, and the implementation of solution procedures into numerical algorithms, are discussed hand-in-hand and with reference to computer programming. This book is an accessible introduction to theoretical and computational fluid dynamics (CFD), written from a modern perspective that unifies theory and numerical practice. There are several additions and subject expansions in the Second Edition of Fluid Dynamics, including new Matlab and FORTRAN codes. Two distinguishing features of the discourse are: solution procedures and algorithms are developed immediately after problem formulations are presented, and numerical methods are introduced on a need-to-know basis and in increasing order of difficulty. Matlab codes are presented and discussed for ...
Efficient molecular dynamics simulations with many-body potentials on graphics processing units
Fan, Zheyong; Vierimaa, Ville; Harju, Ari
2016-01-01
Graphics processing units have been extensively used to accelerate classical molecular dynamics simulations. However, there is much less progress on the acceleration of force evaluations for many-body potentials compared to pairwise ones. In the conventional force evaluation algorithm for many-body potentials, the force, virial stress, and heat current for a given atom are accumulated within different loops, which could result in write conflict between different threads in a CUDA kernel. In this work, we provide a new force evaluation algorithm, which is based on an explicit pairwise force expression for many-body potentials derived recently [Phys. Rev. B 92 (2015) 094301]. In our algorithm, the force, virial stress, and heat current for a given atom can be accumulated within a single thread and is free of write conflicts. We discuss the formulations and algorithms and evaluate their performance. A new open-source code, GPUMD, is developed based on the proposed formulations. For the Tersoff many-body potentia...
Energy Technology Data Exchange (ETDEWEB)
1989-12-01
Remote technology is being used to divert a raffinate feed pipe at the Sellafield fuel reprocessing plant in the UK. Extensive use is being made by the contractor of computer graphics and a full-scale mock-up. (author).
Computer simulation of multiple dynamic photorefractive gratings
DEFF Research Database (Denmark)
Buchhave, Preben
1998-01-01
The benefits of a direct visualization of space-charge grating buildup are described. The visualization is carried out by a simple repetitive computer program, which simulates the basic processes in the band-transport model and displays the result graphically or in the form of numerical data. The....... The simulation sheds light on issues that are not amenable to analytical solutions, such as the spectral content of the wave forms, cross talk in three-beam interaction, and the range of applications of the band-transport model. (C) 1998 Optical Society of America....
Massively parallel simulations of relativistic fluid dynamics on graphics processing units with CUDA
Bazow, Dennis; Strickland, Michael
2016-01-01
Relativistic fluid dynamics is a major component in dynamical simulations of the quark-gluon plasma created in relativistic heavy-ion collisions. Simulations of the full three-dimensional dissipative dynamics of the quark-gluon plasma with fluctuating initial conditions are computationally expensive and typically require some degree of parallelization. In this paper, we present a GPU implementation of the Kurganov-Tadmor algorithm which solves the 3+1d relativistic viscous hydrodynamics equations including the effects of both bulk and shear viscosities. We demonstrate that the resulting CUDA-based GPU code is approximately two orders of magnitude faster than the corresponding serial implementation of the Kurganov-Tadmor algorithm. We validate the code using (semi-)analytic tests such as the relativistic shock-tube and Gubser flow.
Tools for Reactive Distillation Column Design: Graphical and Stage-to-Stage Computation Methods
DEFF Research Database (Denmark)
Sanchez Daza, O.; Cisneros, Eduardo Salvador P.; Hostrup, Martin
2001-01-01
Based on the element mass balance concept, a graphical design method and a stage-to-stage multicomponent design method for reactive distillation columns have been developed. For distillation columns comprising reactive and non-reactive stages, a simple design strategy based on reactive and non......-reactive bubble point calculations is proposed. This strategy tracks the conversion and temperature between the feed and the end stages of the column. An illustrative example highlights the verification of the design strategy through rigorous simulation....
Effectiveness of using CADD (Computer-Aided Design Drafting) to learn engineering design graphics
Energy Technology Data Exchange (ETDEWEB)
Bertoline, G.R.
1987-01-01
One commercial CADD software and one educational CADD software was compared to the use of traditional tools. Engineering-graphics students were divided into three groups. The control group used traditional tools for all their drawings. One experimental group used a commercial CADD software to supplement hand tools and one group used an educational CADD software to supplement traditional tools. These groups were then post-tested using a standardized drafting test. The main findings were: (1) There was no significant difference in the learning of engineering graphics as measured by the post-tests. Supplementing traditional tools with CADD is effective for teaching engineering design graphics. (2) Using CADD for detail drawings such as simple orthographic drawings, sections, and dimensions could be produced in approximately the same amount of time as using traditional tools. (3) It was found that the amount of time needed to solve descriptive geometry problems using CADD was prohibitive. The amount of time to solve some descriptive geometry problems was two or three times greater using CADD versus traditional tools.
Sainsbury-Carter, J. B.; Conaway, J. H.
1973-01-01
The development and implementation of a preprocessor system for the finite element analysis of helicopter fuselages is described. The system utilizes interactive graphics for the generation, display, and editing of NASTRAN data for fuselage models. It is operated from an IBM 2250 cathode ray tube (CRT) console driven by an IBM 370/145 computer. Real time interaction plus automatic data generation reduces the nominal 6 to 10 week time for manual generation and checking of data to a few days. The interactive graphics system consists of a series of satellite programs operated from a central NASTRAN Systems Monitor. Fuselage structural models including the outer shell and internal structure may be rapidly generated. All numbering systems are automatically assigned. Hard copy plots of the model labeled with GRID or elements ID's are also available. General purpose programs for displaying and editing NASTRAN data are included in the system. Utilization of the NASTRAN interactive graphics system has made possible the multiple finite element analysis of complex helicopter fuselage structures within design schedules.
Computational fluid dynamics modeling in yarn engineering
CSIR Research Space (South Africa)
Patanaik, A
2011-07-01
Full Text Available This chapter deals with the application of computational fluid dynamics (CFD) modeling in reducing yarn hairiness during the ring spinning process and thereby “engineering” yarn with desired properties. Hairiness significantly affects the appearance...
Mano, Omer; Clark, Damon A
2017-01-01
Sensory neuroscience seeks to understand and predict how sensory neurons respond to stimuli. Nonlinear components of neural responses are frequently characterized by the second-order Wiener kernel and the closely-related spike-triggered covariance (STC). Recent advances in data acquisition have made it increasingly common and computationally intensive to compute second-order Wiener kernels/STC matrices. In order to speed up this sort of analysis, we developed a graphics processing unit (GPU)-accelerated module that computes the second-order Wiener kernel of a system's response to a stimulus. The generated kernel can be easily transformed for use in standard STC analyses. Our code speeds up such analyses by factors of over 100 relative to current methods that utilize central processing units (CPUs). It works on any modern GPU and may be integrated into many data analysis workflows. This module accelerates data analysis so that more time can be spent exploring parameter space and interpreting data.
A Computational Fluid Dynamics Algorithm on a Massively Parallel Computer
Jespersen, Dennis C.; Levit, Creon
1989-01-01
The discipline of computational fluid dynamics is demanding ever-increasing computational power to deal with complex fluid flow problems. We investigate the performance of a finite-difference computational fluid dynamics algorithm on a massively parallel computer, the Connection Machine. Of special interest is an implicit time-stepping algorithm; to obtain maximum performance from the Connection Machine, it is necessary to use a nonstandard algorithm to solve the linear systems that arise in the implicit algorithm. We find that the Connection Machine ran achieve very high computation rates on both explicit and implicit algorithms. The performance of the Connection Machine puts it in the same class as today's most powerful conventional supercomputers.
Fluid dynamics theory, computation, and numerical simulation
Pozrikidis, C
2017-01-01
This book provides an accessible introduction to the basic theory of fluid mechanics and computational fluid dynamics (CFD) from a modern perspective that unifies theory and numerical computation. Methods of scientific computing are introduced alongside with theoretical analysis and MATLAB® codes are presented and discussed for a broad range of topics: from interfacial shapes in hydrostatics, to vortex dynamics, to viscous flow, to turbulent flow, to panel methods for flow past airfoils. The third edition includes new topics, additional examples, solved and unsolved problems, and revised images. It adds more computational algorithms and MATLAB programs. It also incorporates discussion of the latest version of the fluid dynamics software library FDLIB, which is freely available online. FDLIB offers an extensive range of computer codes that demonstrate the implementation of elementary and advanced algorithms and provide an invaluable resource for research, teaching, classroom instruction, and self-study. This ...
Stork, David G.; Furuichi, Yasuo
2010-02-01
We built a full computer graphics model of Parmigianino's studio, including convex mirror, in order to explore the artist's likely working methods during his execution of Self portrait in a convex mirror (1523-4). Our model supports Vasari's record that the radius of curvature of a convex mirror matched the radius of curvature of the wood panel support. We find that the image in the painting is consistent with a simple horizontal rectilinear room drawn from a slightly re-oriented and re-positioned mirror. Our optical analyses lead us to recommend an alteration to the current display arrangement in the Kunsthistorisches Museum.
Computational Fluid Dynamics in Cardiovascular Disease
Lee, Byoung-kwon
2011-01-01
Computational fluid dynamics (CFD) is a mechanical engineering field for analyzing fluid flow, heat transfer, and associated phenomena, using computer-based simulation. CFD is a widely adopted methodology for solving complex problems in many modern engineering fields. The merit of CFD is developing new and improved devices and system designs, and optimization is conducted on existing equipment through computational simulations, resulting in enhanced efficiency and lower operating costs. Howev...
Wilson, J Adam; Williams, Justin C
2009-01-01
The clock speeds of modern computer processors have nearly plateaued in the past 5 years. Consequently, neural prosthetic systems that rely on processing large quantities of data in a short period of time face a bottleneck, in that it may not be possible to process all of the data recorded from an electrode array with high channel counts and bandwidth, such as electrocorticographic grids or other implantable systems. Therefore, in this study a method of using the processing capabilities of a graphics card [graphics processing unit (GPU)] was developed for real-time neural signal processing of a brain-computer interface (BCI). The NVIDIA CUDA system was used to offload processing to the GPU, which is capable of running many operations in parallel, potentially greatly increasing the speed of existing algorithms. The BCI system records many channels of data, which are processed and translated into a control signal, such as the movement of a computer cursor. This signal processing chain involves computing a matrix-matrix multiplication (i.e., a spatial filter), followed by calculating the power spectral density on every channel using an auto-regressive method, and finally classifying appropriate features for control. In this study, the first two computationally intensive steps were implemented on the GPU, and the speed was compared to both the current implementation and a central processing unit-based implementation that uses multi-threading. Significant performance gains were obtained with GPU processing: the current implementation processed 1000 channels of 250 ms in 933 ms, while the new GPU method took only 27 ms, an improvement of nearly 35 times.
Computer Graphic Design Using Auto-CAD and Plug Nozzle Research
Rogers, Rayna C.
2004-01-01
The purpose of creating computer generated images varies widely. They can be use for computational fluid dynamics (CFD), or as a blueprint for designing parts. The schematic that I will be working on the summer will be used to create nozzles that are a part of a larger system. At this phase in the project, the nozzles needed for the systems have been fabricated. One part of my mission is to create both three dimensional and two dimensional models on Auto-CAD 2002 of the nozzles. The research on plug nozzles will allow me to have a better understanding of how they assist in the thrust need for a missile to take off. NASA and the United States military are working together to develop a new design concept. On most missiles a convergent-divergent nozzle is used to create thrust. However, the two are looking into different concepts for the nozzle. The standard convergent-divergent nozzle forces a mixture of combustible fluids and air through a smaller area in comparison to where the combination was mixed. Once it passes through the smaller area known as A8 it comes out the end of the nozzle which is larger the first or area A9. This creates enough thrust for the mechanism whether it is an F-18 fighter jet or a missile. The A9 section of the convergent-divergent nozzle has a mechanism that controls how large A9 can be. This is needed because the pressure of the air coming out nozzle must be equal to that of the ambient pressure other wise there will be a loss of performance in the machine. The plug nozzle however does not need to have an A9 that can vary. When the air flow comes out it can automatically sense what the ambient pressure is and will adjust accordingly. The objective of this design is to create a plug nozzle that is not as complicated mechanically as it counterpart the convergent-divergent nozzle.
Visualization and computation of hovering mode vortex dynamics
Freymuth, Peter; Gustafson, Karl E.; Leben, Robert
Results from experimental and numerical simulations of the unsteady hovering flight of small birds or insects are presented in extensive photographs and computer graphics and discussed in detail. In the flow-visualization experiments, an airfoil in combined pitching and plunging motion is used to generate a thrusting jet in still air, producing in addition a vortex street with rotation opposite to that of a Karman street. The numerical studies are based on an extension of the robust multigrid method of Gustafson and Leben (1986 and 1988) to hovering-mode vortex dynamics. The derivation of the governing equations is outlined, and it is shown that the numerical and experimental results are in good qualitative agreement.
Energy Technology Data Exchange (ETDEWEB)
Jalbert, J.S.; Dobson, J.E.
1976-10-03
An energy facility site-screening methodology which permits the land resource planner to identify candidate siting areas was developed. Through the use of spatial analysis procedures and computer graphics, a selection of candidate areas is obtained. Specific sites then may be selected from among candidate areas for environmental impact analysis. The computerized methodology utilizes a cell-based geographic information system for specifying the suitability of candidate areas for an energy facility. The criteria to be considered may be specified by the user and weighted in terms of importance. Three primary computer programs have been developed. These programs produce thematic maps, proximity calculations, and suitability calculations. Programs are written so as to be transferrable to regional planning or regulatory agencies to assist in rational and comprehensive power plant site identification and analysis.
Dynamics and computation in functional shifts
Namikawa, Jun; Hashimoto, Takashi
2004-07-01
We introduce a new type of shift dynamics as an extended model of symbolic dynamics, and investigate the characteristics of shift spaces from the viewpoints of both dynamics and computation. This shift dynamics is called a functional shift, which is defined by a set of bi-infinite sequences of some functions on a set of symbols. To analyse the complexity of functional shifts, we measure them in terms of topological entropy, and locate their languages in the Chomsky hierarchy. Through this study, we argue that considering functional shifts from the viewpoints of both dynamics and computation gives us opposite results about the complexity of systems. We also describe a new class of shift spaces whose languages are not recursively enumerable.
Relativistic Hydrodynamics on Graphic Cards
Gerhard, Jochen; Bleicher, Marcus
2012-01-01
We show how to accelerate relativistic hydrodynamics simulations using graphic cards (graphic processing units, GPUs). These improvements are of highest relevance e.g. to the field of high-energetic nucleus-nucleus collisions at RHIC and LHC where (ideal and dissipative) relativistic hydrodynamics is used to calculate the evolution of hot and dense QCD matter. The results reported here are based on the Sharp And Smooth Transport Algorithm (SHASTA), which is employed in many hydrodynamical models and hybrid simulation packages, e.g. the Ultrarelativistic Quantum Molecular Dynamics model (UrQMD). We have redesigned the SHASTA using the OpenCL computing framework to work on accelerators like graphic processing units (GPUs) as well as on multi-core processors. With the redesign of the algorithm the hydrodynamic calculations have been accelerated by a factor 160 allowing for event-by-event calculations and better statistics in hybrid calculations.
Neural circuits as computational dynamical systems.
Sussillo, David
2014-04-01
Many recent studies of neurons recorded from cortex reveal complex temporal dynamics. How such dynamics embody the computations that ultimately lead to behavior remains a mystery. Approaching this issue requires developing plausible hypotheses couched in terms of neural dynamics. A tool ideally suited to aid in this question is the recurrent neural network (RNN). RNNs straddle the fields of nonlinear dynamical systems and machine learning and have recently seen great advances in both theory and application. I summarize recent theoretical and technological advances and highlight an example of how RNNs helped to explain perplexing high-dimensional neurophysiological data in the prefrontal cortex.
Three-Dimensional Computational Fluid Dynamics
Energy Technology Data Exchange (ETDEWEB)
Haworth, D.C.; O' Rourke, P.J.; Ranganathan, R.
1998-09-01
Computational fluid dynamics (CFD) is one discipline falling under the broad heading of computer-aided engineering (CAE). CAE, together with computer-aided design (CAD) and computer-aided manufacturing (CAM), comprise a mathematical-based approach to engineering product and process design, analysis and fabrication. In this overview of CFD for the design engineer, our purposes are three-fold: (1) to define the scope of CFD and motivate its utility for engineering, (2) to provide a basic technical foundation for CFD, and (3) to convey how CFD is incorporated into engineering product and process design.
Single neuron dynamics and computation.
Brunel, Nicolas; Hakim, Vincent; Richardson, Magnus J E
2014-04-01
At the single neuron level, information processing involves the transformation of input spike trains into an appropriate output spike train. Building upon the classical view of a neuron as a threshold device, models have been developed in recent years that take into account the diverse electrophysiological make-up of neurons and accurately describe their input-output relations. Here, we review these recent advances and survey the computational roles that they have uncovered for various electrophysiological properties, for dendritic arbor anatomy as well as for short-term synaptic plasticity.
1992-01-01
scientific visualization technology possible by hardware such as bitmap graphics and the mouse, today. Electronic books , to be used, for example, for...colleagues In electronic books there will be the need for a system, including the underlying support structure, the inplemen- designer or kr.)wledge
Graphic interface for numerical commands on the USB port of PC compatible computers
Directory of Open Access Journals (Sweden)
Popa Elena
2017-01-01
Full Text Available Computers are increasingly used in the present technological processes. Several numerical input/ output electronic modules were designed and made to support computer automated technological process in the wood industry. This paper presents the software for these modules, built in the Delphi language and aimed to obtain numerical commands by using the USB port of a computer. As modern computers are no longer provided with parallel ports, a K8055 USB Experiment Interface Board manufactured by VELLEMAN was used. The board includes a PIC16C745-IP microcontroller, which enables communication via specific software.
Visualizing History: Computer Technology and the Graphic Presentation of the Past
Moss, Mark
2004-01-01
Computer technology has impacted both the study and idea of history in a number of ways. The Internet has provided numerous web-sites for students to read, see and look into for historical information. Historians, both professional and public have also begun to utilize the computer in a variety of ways, both in academic terms as well as leisure…
Dynamic Associations in Nonlinear Computing Arrays
Huberman, B. A.; Hogg, T.
1985-10-01
We experimentally show that nonlinear parallel arrays can be made to compute with attractors. This leads to fast adaptive behavior in which dynamical associations can be made between different inputs which initially produce sharply distinct outputs. We first define a set of simple local procedures which allow a general computing structure to change its state in time so as to produce classical Pavlovian conditioning. We then examine the dynamics of coalescence and dissociation of attractors with a number of quantitative experiments. We also show how such arrays exhibit generalization and differentiation of inputs in their behavior.
An introduction to Computational Fluid Dynamics
DEFF Research Database (Denmark)
Sørensen, Lars Schiøtt
1999-01-01
CFD is the shortname for Computational Fluid Dynamics and is a numerical method by means of which we can analyze systems containing fluids. For instance systems dealing with heat flow or smoke control systems acting when a fire occur in a building.......CFD is the shortname for Computational Fluid Dynamics and is a numerical method by means of which we can analyze systems containing fluids. For instance systems dealing with heat flow or smoke control systems acting when a fire occur in a building....
Inverse problems in stochastic computational dynamics
Capiez-Lernout, Evangéline; Soize, Christian
2008-01-01
International audience; This paper deals with robust updating of dynamical systems using stochastic computational models for which model and parameter uncertainties are taken into account by the nonparametric probabilistic approach. Such a problem is formulated as an inverse problem consisting in identifying the parameters of the mean computational model and the parameters of the probabilistic model of uncertainties. This inverse problem leads us to solve an optimization problem for which the...
Yoo, Youngjin; Prasloski, Thomas; Vavasour, Irene; MacKay, Alexander; Traboulsee, Anthony L; Li, David K B; Tam, Roger C
2015-03-01
To develop a fast algorithm for computing myelin maps from multiecho T2 relaxation data using parallel computation with multicore CPUs and graphics processing units (GPUs). Using an existing MATLAB (MathWorks, Natick, MA) implementation with basic (nonalgorithm-specific) parallelism as a guide, we developed a new version to perform the same computations but using C++ to optimize the hybrid utilization of multicore CPUs and GPUs, based on experimentation to determine which algorithmic components would benefit from CPU versus GPU parallelization. Using 32-echo T2 data of dimensions 256 × 256 × 7 from 17 multiple sclerosis patients and 18 healthy subjects, we compared the two methods in terms of speed, myelin values, and the ability to distinguish between the two patient groups using Student's t-tests. The new method was faster than the MATLAB implementation by 4.13 times for computing a single map and 14.36 times for batch-processing 10 scans. The two methods produced very similar myelin values, with small and explainable differences that did not impact the ability to distinguish the two patient groups. The proposed hybrid multicore approach represents a more efficient alternative to MATLAB, especially for large-scale batch processing. © 2014 Wiley Periodicals, Inc.
Pitfalls in Graphical Computation, or Why a Single Graph Isn't Enough.
Demana, Franklin; Waits, Bert K.
1988-01-01
Argues that while microcomputer and graphing calculators have evolved to a stage where they should be used routinely by mathematics students at all levels, there is sometimes potential to mislead students with computer generated graphs. Examples are included. (PK)
A computer graphical user interface for survival mixture modelling of recurrent infections.
Lee, Andy H; Zhao, Yun; Yau, Kelvin K W; Ng, S K
2009-03-01
Recurrent infections data are commonly encountered in medical research, where the recurrent events are characterised by an acute phase followed by a stable phase after the index episode. Two-component survival mixture models, in both proportional hazards and accelerated failure time settings, are presented as a flexible method of analysing such data. To account for the inherent dependency of the recurrent observations, random effects are incorporated within the conditional hazard function, in the manner of generalised linear mixed models. Assuming a Weibull or log-logistic baseline hazard in both mixture components of the survival mixture model, an EM algorithm is developed for the residual maximum quasi-likelihood estimation of fixed effect and variance component parameters. The methodology is implemented as a graphical user interface coded using Microsoft visual C++. Application to model recurrent urinary tract infections for elderly women is illustrated, where significant individual variations are evident at both acute and stable phases. The survival mixture methodology developed enable practitioners to identify pertinent risk factors affecting the recurrent times and to draw valid conclusions inferred from these correlated and heterogeneous survival data.
Deterministic Graphical Games Revisited
DEFF Research Database (Denmark)
Andersson, Daniel; Hansen, Kristoffer Arnsfelt; Miltersen, Peter Bro
2008-01-01
We revisit the deterministic graphical games of Washburn. A deterministic graphical game can be described as a simple stochastic game (a notion due to Anne Condon), except that we allow arbitrary real payoffs but disallow moves of chance. We study the complexity of solving deterministic graphical...... games and obtain an almost-linear time comparison-based algorithm for computing an equilibrium of such a game. The existence of a linear time comparison-based algorithm remains an open problem....
Institute of Scientific and Technical Information of China (English)
ZHOU Chun; SHEN Guanxin; ZHU Huifen; YANG Jing; ZHANG Yue; FENG Jiannan; SHEN Beifen
2000-01-01
A three-dimensional (3D) graphic model of a single-chain Fv (scFv) which was derived from an anti-human placental acidic isoferritin (PAF) monoclonal antibody (Mab) was constructed by a homologous protein-predicting computer algorithm on Silicon graphic computer station.The structure, surface static electricity and hydrophobicity of scFv were investigated. Computer graphic modelling indicated that all regions of scFv including the linker, variable regions of the heavy (VH) and light (VL) chains were suitable. The VH region and the VL region were involved in composing the "hydrophobic pocket". The linker was drifted away VH and VL regions. The complementarity determining regions (CDRs) of VH and VL regions surrounded the "hydrophobic pocket". This study provides a theory basis for improving antibody affinity, investigating antibody structure and analyzing the functions of VH and VL regions in antibody activity.
Directory of Open Access Journals (Sweden)
Ioan Catalin VLAD
2012-11-01
Full Text Available Purpose: In recent studies perineural invasion (PNI is associated with poor survival rates in rectal cancer, but the impact of PNI it’s still controversial. We assessed PNI as a potential prognostic factor in rectal cancer. Patients and Methods: We analyzed 317 patients with rectal cancer resected at The Oncology Institute”Prof. Dr. Ion Chiricuţă” Cluj-Napoca, between January 2000 and December 2008. Tumors were reviewed for PNI by a pathologist. Patients data were reviewed and entered into a comprehensive database. The statistical analysis in our study was carried out in R environment for statistical computing and graphics, version 1.15.1. Overall and disease-free survivals were determined using the Kaplan-Meier method, and multivariate analysis using the Cox multiple hazards model. Results were compared using the log-rank test. Results: In our study PNI was identified in 19% of tumors. The 5-year disease-free survival rate was higher for patients with PNI-negative tumors versus those with PNI-positive tumors (57.31% vs. 36.99%, p=0.009. The 5-year overall survival rate was 59.15% for PNI-negative tumors versus 39.19% for PNI-positive tumors (p=0.014. On multivariate analysis, PNI was an independent prognostic factor for overall survival (Hazard Ratio = 0.6; 95% CI = 0.41 to 0.87; p = 0.0082. Conclusions: PNI can be considered an independent prognostic factor of outcomes in patients with rectal cancer. PNI should be taken into account when selecting patients for adjuvant treatment. R environment for statistical computing and graphics is complex yet easy to use software that has proven to be efficient in our clinical study.
RESEARCH ON DYNAMIC PERFORMANCE IN POSTER GRAPHICS%海报图形动态表现探究
Institute of Scientific and Technical Information of China (English)
张曼华
2016-01-01
Behaviors of human-beings and other creatures are boldly used by graphic designers, thus two dynamic performances of poster graphics are formed, namely dynamic caused by human behavior and that caused by other biological behavior.Through these forms, we find that there is a certain connotation and reason when designers use dynamic methods, that is, to reflect a combination of subject need, participation psychology and fresh feeling,etc.%平面设计师通过对人类自身与其它生物行为的大胆利用，形成了海报图形的动态表现，即人类自身行为造成的动态和其它生物行为形成的动态两个方面。透过这些表现形式，发现设计师运用动态手法是有一定内涵和原因的，是主题需要、参与心理和新鲜感受等方面的综合反映。
Computational fluid dynamics in oil burner design
Energy Technology Data Exchange (ETDEWEB)
Butcher, T.A. [Brookhaven National Labs., Upton, NY (United States)
1997-09-01
In Computational Fluid Dynamics, the differential equations which describe flow, heat transfer, and mass transfer are approximately solved using a very laborious numerical procedure. Flows of practical interest to burner designs are always turbulent, adding to the complexity of requiring a turbulence model. This paper presents a model for burner design.
Engineering applications of computational fluid dynamics
Awang, Mokhtar
2015-01-01
This volume presents the results of Computational Fluid Dynamics (CFD) analysis that can be used for conceptual studies of product design, detail product development, process troubleshooting. It demonstrates the benefit of CFD modeling as a cost saving, timely, safe and easy to scale-up methodology.
From Cnn Dynamics to Cellular Wave Computers
Roska, Tamas
2013-01-01
Embedded in a historical overview, the development of the Cellular Wave Computing paradigm is presented, starting from the standard CNN dynamics. The theoretical aspects, the physical implementation, the innovation process, as well as the biological relevance are discussed in details. Finally, the latest developments, the physical versus virtual cellular machines, as well as some open questions are presented.
A Stochastic Dynamic Model of Computer Viruses
Directory of Open Access Journals (Sweden)
Chunming Zhang
2012-01-01
Full Text Available A stochastic computer virus spread model is proposed and its dynamic behavior is fully investigated. Specifically, we prove the existence and uniqueness of positive solutions, and the stability of the virus-free equilibrium and viral equilibrium by constructing Lyapunov functions and applying Ito's formula. Some numerical simulations are finally given to illustrate our main results.
The status of Computational Fluis Dynamics
DEFF Research Database (Denmark)
Nielsen, Peter Vilhelm; Liu, Li; Peng, Lei
2016-01-01
Computational fluid dynamics (CFD) was first introduced in the building ventilation industry in the 1970s. Since then, it has been increasingly used as testified by the growth of the number of peer-reviewed articles, which was less than 10 per year in the 1990s and 60 to 70 per year in the recent...
Computational Fluid Dynamics in Ventilation Design
DEFF Research Database (Denmark)
Nielsen, Peter V.
2008-01-01
This paper is based on the new REHVA Guidebook Computational Fluid Dynamics in Ventilation Design (Nielsen et al. 2007) written by Peter V. Nielsen, Francis(Nielsen 2007) written by Peter V. Nielsen, Francis Allard, Hazim B. Awbi, Lars Davidson and Alois Schälin. The guidebook is made for people...
Computational Fluid Dynamics and Ventilation Airflow
DEFF Research Database (Denmark)
Nielsen, Peter Vilhelm
2014-01-01
Computational fluid dynamics (CFD) was first introduced in the ventilation industry in the 1970s. CFD has been increasingly used since then, as testified by the number of peer-reviewed articles, which was less than 10 per year in the 1990s, and which is now 60 to 70 per year. This article discusses...
The use of graphic design in an interactive computer teaching program.
Nixon, M S; Fishman, E K; Magid, D; Hennessey, J G; Ney, D R
1991-04-01
The widespread diffusion of affordable computers into the scientific and educational community has provided the opportunity to design medical and scientific teaching programs illustrated either by hand or by utilizing commercially available software and manipulating existing computer generated images. The medical illustrator can provide the ideal aesthetic link between text format information and the visual representation of such knowledge in a concise presentation format. The availability of interactive multimedia programs has given the medical illustrator an environment to create and enhance Hypermedia designed specifically for the purpose of medical education. This paper will focus on the incorporation of illustration and screen design into "CT The Game," an experimental medical teaching program currently being developed in the Johns Hopkins Body CT Imaging Laboratory. The program is designed to provide an enjoyable approach to learning Computed Tomography (CT), and is directed toward an audience of medical students, residents, and fellows.
Mano, Omer
2017-01-01
Sensory neuroscience seeks to understand and predict how sensory neurons respond to stimuli. Nonlinear components of neural responses are frequently characterized by the second-order Wiener kernel and the closely-related spike-triggered covariance (STC). Recent advances in data acquisition have made it increasingly common and computationally intensive to compute second-order Wiener kernels/STC matrices. In order to speed up this sort of analysis, we developed a graphics processing unit (GPU)-accelerated module that computes the second-order Wiener kernel of a system’s response to a stimulus. The generated kernel can be easily transformed for use in standard STC analyses. Our code speeds up such analyses by factors of over 100 relative to current methods that utilize central processing units (CPUs). It works on any modern GPU and may be integrated into many data analysis workflows. This module accelerates data analysis so that more time can be spent exploring parameter space and interpreting data. PMID:28068420
Computational Methods in Stochastic Dynamics Volume 2
Stefanou, George; Papadopoulos, Vissarion
2013-01-01
The considerable influence of inherent uncertainties on structural behavior has led the engineering community to recognize the importance of a stochastic approach to structural problems. Issues related to uncertainty quantification and its influence on the reliability of the computational models are continuously gaining in significance. In particular, the problems of dynamic response analysis and reliability assessment of structures with uncertain system and excitation parameters have been the subject of continuous research over the last two decades as a result of the increasing availability of powerful computing resources and technology. This book is a follow up of a previous book with the same subject (ISBN 978-90-481-9986-0) and focuses on advanced computational methods and software tools which can highly assist in tackling complex problems in stochastic dynamic/seismic analysis and design of structures. The selected chapters are authored by some of the most active scholars in their respective areas and...
Knibbe, H.P.
2015-01-01
The oil and gas industry makes use of computational intensive algorithms to provide an image of the subsurface. The image is obtained by sending wave energy into the subsurface and recording the signal required for a seismic wave to reflect back to the surface from the Earth interfaces that may have
Fast traffic noise mapping of cities using the graphics processing unit of a personal computer
Salomons, E.M.; Zhou, H.; Lohman, W.J.A.
2014-01-01
Traffic noise mapping of cities requires large computer calculation times. This originates from the large number of point-to-point sound propagation calculations that must be performed. In this article it is demonstrated that noise mapping calculation times can be reduced considerably by the use of
Knibbe, H.P.
2015-01-01
The oil and gas industry makes use of computational intensive algorithms to provide an image of the subsurface. The image is obtained by sending wave energy into the subsurface and recording the signal required for a seismic wave to reflect back to the surface from the Earth interfaces that may have
Demidov, A.; Eschlböck-Fuchs, S.; Kazakov, A. Ya.; Gornushkin, I. B.; Kolmhofer, P. J.; Pedarnig, J. D.; Huber, N.; Heitz, J.; Schmid, T.; Rössler, R.; Panne, U.
2016-11-01
The improved Monte-Carlo (MC) method for standard-less analysis in laser induced breakdown spectroscopy (LIBS) is presented. Concentrations in MC LIBS are found by fitting model-generated synthetic spectra to experimental spectra. The current version of MC LIBS is based on the graphic processing unit (GPU) computation and reduces the analysis time down to several seconds per spectrum/sample. The previous version of MC LIBS which was based on the central processing unit (CPU) computation requested unacceptably long analysis times of 10's minutes per spectrum/sample. The reduction of the computational time is achieved through the massively parallel computing on the GPU which embeds thousands of co-processors. It is shown that the number of iterations on the GPU exceeds that on the CPU by a factor > 1000 for the 5-dimentional parameter space and yet requires > 10-fold shorter computational time. The improved GPU-MC LIBS outperforms the CPU-MS LIBS in terms of accuracy, precision, and analysis time. The performance is tested on LIBS-spectra obtained from pelletized powders of metal oxides consisting of CaO, Fe2O3, MgO, and TiO2 that simulated by-products of steel industry, steel slags. It is demonstrated that GPU-based MC LIBS is capable of rapid multi-element analysis with relative error between 1 and 10's percent that is sufficient for industrial applications (e.g. steel slag analysis). The results of the improved GPU-based MC LIBS are positively compared to that of the CPU-based MC LIBS as well as to the results of the standard calibration-free (CF) LIBS based on the Boltzmann plot method.
Directory of Open Access Journals (Sweden)
J. Adam Wilson
2009-07-01
Full Text Available The clock speeds of modern computer processors have nearly plateaued in the past five years. Consequently, neural prosthetic systems that rely on processing large quantities of data in a short period of time face a bottleneck, in that it may not be possible to process all of the data recorded from an electrode array with high channel counts and bandwidth, such as electrocorticographic grids or other implantable systems. Therefore, in this study a method of using the processing capabilities of a graphics card (GPU was developed for real-time neural signal processing of a brain-computer interface (BCI. The NVIDIA CUDA system was used to offload processing to the GPU, which is capable of running many operations in parallel, potentially greatly increasing the speed of existing algorithms. The BCI system records many channels of data, which are processed and translated into a control signal, such as the movement of a computer cursor. This signal processing chain involves computing a matrix-matrix multiplication (i.e., a spatial filter, followed by calculating the power spectral density on every channel using an auto-regressive method, and finally classifying appropriate features for control. In this study, the first two computationally-intensive steps were implemented on the GPU, and the speed was compared to both the current implementation and a CPU-based implementation that uses multi-threading. Significant performance gains were obtained with GPU processing: the current implementation processed 1000 channels in 933 ms, while the new GPU method took only 27 ms, an improvement of nearly 35 times.
Computational Fluid Dynamics In GARUDA Grid Environment
Roy, Chandra Bhushan
2011-01-01
GARUDA Grid developed on NKN (National Knowledge Network) network by Centre for Development of Advanced Computing (C-DAC) hubs High Performance Computing (HPC) Clusters which are geographically separated all over India. C-DAC has been associated with development of HPC infrastructure since its establishment in year 1988. The Grid infrastructure provides a secure and efficient way of accessing heterogeneous resource . Enabling scientific applications on Grid has been researched for some time now. In this regard we have successfully enabled Computational Fluid Dynamics (CFD) application which can help CFD community as a whole in effective manner to carry out computational research which requires huge compuational resource beyond once in house capability. This work is part of current on-going project Grid GARUDA funded by Department of Information Technology.
Computationally Efficient Multiconfigurational Reactive Molecular Dynamics.
Yamashita, Takefumi; Peng, Yuxing; Knight, Chris; Voth, Gregory A
2012-12-11
It is a computationally demanding task to explicitly simulate the electronic degrees of freedom in a system to observe the chemical transformations of interest, while at the same time sampling the time and length scales required to converge statistical properties and thus reduce artifacts due to initial conditions, finite-size effects, and limited sampling. One solution that significantly reduces the computational expense consists of molecular models in which effective interactions between particles govern the dynamics of the system. If the interaction potentials in these models are developed to reproduce calculated properties from electronic structure calculations and/or ab initio molecular dynamics simulations, then one can calculate accurate properties at a fraction of the computational cost. Multiconfigurational algorithms model the system as a linear combination of several chemical bonding topologies to simulate chemical reactions, also sometimes referred to as "multistate". These algorithms typically utilize energy and force calculations already found in popular molecular dynamics software packages, thus facilitating their implementation without significant changes to the structure of the code. However, the evaluation of energies and forces for several bonding topologies per simulation step can lead to poor computational efficiency if redundancy is not efficiently removed, particularly with respect to the calculation of long-ranged Coulombic interactions. This paper presents accurate approximations (effective long-range interaction and resulting hybrid methods) and multiple-program parallelization strategies for the efficient calculation of electrostatic interactions in reactive molecular simulations.
Graphics and visualization principles & algorithms
Theoharis, T; Platis, Nikolaos; Patrikalakis, Nicholas M
2008-01-01
Computer and engineering collections strong in applied graphics and analysis of visual data via computer will find Graphics & Visualization: Principles and Algorithms makes an excellent classroom text as well as supplemental reading. It integrates coverage of computer graphics and other visualization topics, from shadow geneeration and particle tracing to spatial subdivision and vector data visualization, and it provides a thorough review of literature from multiple experts, making for a comprehensive review essential to any advanced computer study.-California Bookw
Graphical Model Theory for Wireless Sensor Networks
Energy Technology Data Exchange (ETDEWEB)
Davis, William B.
2002-12-08
Information processing in sensor networks, with many small processors, demands a theory of computation that allows the minimization of processing effort, and the distribution of this effort throughout the network. Graphical model theory provides a probabilistic theory of computation that explicitly addresses complexity and decentralization for optimizing network computation. The junction tree algorithm, for decentralized inference on graphical probability models, can be instantiated in a variety of applications useful for wireless sensor networks, including: sensor validation and fusion; data compression and channel coding; expert systems, with decentralized data structures, and efficient local queries; pattern classification, and machine learning. Graphical models for these applications are sketched, and a model of dynamic sensor validation and fusion is presented in more depth, to illustrate the junction tree algorithm.
The Brain Dynamics of Linguistic Computation
Directory of Open Access Journals (Sweden)
Elliot eMurphy
2015-10-01
Full Text Available Neural oscillations at distinct frequencies are increasingly being related to a number of basic and higher cognitive faculties. Oscillations enable the construction of coherently organised neuronal assemblies through establishing transitory temporal correlations. By exploring the elementary operations of the language faculty – labeling, concatenation, cyclic transfer – alongside neural dynamics, a new model of linguistic computation is proposed. It is argued that the universality of language, and the true biological source of Universal Grammar, is not to be found purely in the genome as has long been suggested, but more specifically within the extraordinarily preserved nature of mammalian brain rhythms employed in the computation of linguistic structures. Computational-representational theories are used as a guide in investigating the neurobiological foundations of the human ‘cognome’ – the set of computations performed by the nervous system – and new directions are suggested for how the dynamics of brain (the ‘dynome’ operates and execute linguistic operations. The extent to which brain rhythms are the suitable neuronal processes which can capture the computational properties of the human language faculty is considered against a backdrop of existing cartographic research into the localisation of linguistic interpretation. Particular focus is placed on labeling, the operation elsewhere argued to be species-specific. A Basic Label model of the human cognome-dynome is proposed, leading to clear, causally-addressable empirical predictions, to be investigated by a suggested research program, Dynamic Cognomics. In addition, a distinction between minimal and maximal degrees of explanation is introduced to differentiate between the depth of analysis provided by cartographic, rhythmic, neurochemical and other approaches to computation.
The brain dynamics of linguistic computation.
Murphy, Elliot
2015-01-01
Neural oscillations at distinct frequencies are increasingly being related to a number of basic and higher cognitive faculties. Oscillations enable the construction of coherently organized neuronal assemblies through establishing transitory temporal correlations. By exploring the elementary operations of the language faculty-labeling, concatenation, cyclic transfer-alongside neural dynamics, a new model of linguistic computation is proposed. It is argued that the universality of language, and the true biological source of Universal Grammar, is not to be found purely in the genome as has long been suggested, but more specifically within the extraordinarily preserved nature of mammalian brain rhythms employed in the computation of linguistic structures. Computational-representational theories are used as a guide in investigating the neurobiological foundations of the human "cognome"-the set of computations performed by the nervous system-and new directions are suggested for how the dynamics of the brain (the "dynome") operate and execute linguistic operations. The extent to which brain rhythms are the suitable neuronal processes which can capture the computational properties of the human language faculty is considered against a backdrop of existing cartographic research into the localization of linguistic interpretation. Particular focus is placed on labeling, the operation elsewhere argued to be species-specific. A Basic Label model of the human cognome-dynome is proposed, leading to clear, causally-addressable empirical predictions, to be investigated by a suggested research program, Dynamic Cognomics. In addition, a distinction between minimal and maximal degrees of explanation is introduced to differentiate between the depth of analysis provided by cartographic, rhythmic, neurochemical, and other approaches to computation.
Tsatsanidi, K N; Pugaev, A V; Gordeev, P S; Sandrikov, V A; Mukha, A V; Gambarian, A R
1991-02-01
Intraoperative cholangio-manometry with a miniature tensor sensor and graphic recording of the results were conducted to study the function of the major duodenal papilla in 53 patients. A periodical activity of the ampulla of the papilla was revealed, which was characterized by certain values of the peak and basal pressure, and duration of contraction and relaxation periods. The numerical values and the pattern of the pressure curve differed in patients with obstructive cholecystitis, biliary pancreatitis, and a concrement incarcerated in the ampulla of the papilla. The informativeness of the study increases with the use of the glucagon test.
Molecular dynamics for long-range interacting systems on Graphic Processing Units
Filho, Tarcísio M Rocha
2012-01-01
We present implementations of a fourth-order symplectic integrator on graphic processing units for three $N$-body models with long-range interactions of general interest: the Hamiltonian Mean Field, Ring and two-dimensional self-gravitating models. We discuss the algorithms, speedups and errors using one and two GPU units. Speedups can be as high as 140 compared to a serial code, and the overall relative error in the total energy is of the same order of magnitude as for the CPU code. The number of particles used in the tests range from 10,000 to 50,000,000 depending on the model.
Massanes, Francesc; Cadennes, Marie; Brankov, Jovan G.
2011-07-01
We describe and evaluate a fast implementation of a classical block-matching motion estimation algorithm for multiple graphical processing units (GPUs) using the compute unified device architecture computing engine. The implemented block-matching algorithm uses summed absolute difference error criterion and full grid search (FS) for finding optimal block displacement. In this evaluation, we compared the execution time of a GPU and CPU implementation for images of various sizes, using integer and noninteger search grids. The results show that use of a GPU card can shorten computation time by a factor of 200 times for integer and 1000 times for a noninteger search grid. The additional speedup for a noninteger search grid comes from the fact that GPU has built-in hardware for image interpolation. Further, when using multiple GPU cards, the presented evaluation shows the importance of the data splitting method across multiple cards, but an almost linear speedup with a number of cards is achievable. In addition, we compared the execution time of the proposed FS GPU implementation with two existing, highly optimized nonfull grid search CPU-based motion estimations methods, namely implementation of the Pyramidal Lucas Kanade Optical flow algorithm in OpenCV and simplified unsymmetrical multi-hexagon search in H.264/AVC standard. In these comparisons, FS GPU implementation still showed modest improvement even though the computational complexity of FS GPU implementation is substantially higher than non-FS CPU implementation. We also demonstrated that for an image sequence of 720 × 480 pixels in resolution commonly used in video surveillance, the proposed GPU implementation is sufficiently fast for real-time motion estimation at 30 frames-per-second using two NVIDIA C1060 Tesla GPU cards.
Knibbe, H.P.
2015-01-01
The oil and gas industry makes use of computational intensive algorithms to provide an image of the subsurface. The image is obtained by sending wave energy into the subsurface and recording the signal required for a seismic wave to reflect back to the surface from the Earth interfaces that may have different physical properties. A seismic wave is usually generated by shots of known frequencies, placed close to the surface on land or close to the water surface in the sea. Returning waves are ...
Schweppe, M; Geigel, J
2011-01-01
Industry has increasingly emphasized the need for "soft" or interpersonal skills development and team-building experience in the college curriculum. Here, we discuss our experiences with providing such opportunities via a collaborative project called the Virtual Theater. In this joint project between the Rochester Institute of Technology's School of Design and Department of Computer Science, the goal is to enable live performance in a virtual space with participants in different physical locales. Students work in teams, collaborating with other students in and out of their disciplines.
Huang, Shuo; Liu, Jing
2010-05-01
Application of clinical digital medical imaging has raised many tough issues to tackle, such as data storage, management, and information sharing. Here we investigated a mobile phone based medical image management system which is capable of achieving personal medical imaging information storage, management and comprehensive health information analysis. The technologies related to the management system spanning the wireless transmission technology, the technical capabilities of phone in mobile health care and management of mobile medical database were discussed. Taking medical infrared images transmission between phone and computer as an example, the working principle of the present system was demonstrated.
Voronin, A. A.; Zheltikov, A. M.
2016-09-01
The propagation of high-power ultrashort light pulses involves intricate nonlinear spatio-temporal dynamics where various spectral-temporal field transformation effects are strongly coupled to the beam dynamics, which, in turn, varies from the leading to the trailing edge of the pulse. Analysis of this nonlinear dynamics, accompanied by spatial instabilities, beam breakup into multiple filaments, and unique phenomena leading to the generation of extremely short optical field waveforms, is equivalent in its computational complexity to a simulation of the time evolution of a few billion-dimensional physical system. Such an analysis requires exaflops of computational operations and is usually performed on high-performance supercomputers. Here, we present methods of physical modeling and numerical analysis that allow problems of this class to be solved on a laboratory computer boosted by a cluster of graphic accelerators. Exaflop computations performed with the application of these methods reveal new unique phenomena in the spatio-temporal dynamics of high-power ultrashort laser pulses. We demonstrate that unprecedentedly short light bullets can be generated as a part of that dynamics, providing optical field localization in both space and time through a delicate balance between dispersion and nonlinearity with simultaneous suppression of diffraction-induced beam divergence due to the joint effect of Kerr and ionization nonlinearities.
Computational fluid dynamics using CATIA created geometry
Gengler, Jeanne E.
1989-07-01
A method has been developed to link the geometry definition residing on a CAD/CAM system with a computational fluid dynamics (CFD) tool needed to evaluate aerodynamic designs and requiring the memory capacity of a supercomputer. Requirements for surfaces suitable for CFD analysis are discussed. Techniques for developing surfaces and verifying their smoothness are compared, showing the capability of the CAD/CAM system. The utilization of a CAD/CAM system to create a computational mesh is explained, and the mesh interaction with the geometry and input file preparation for the CFD analysis is discussed.
Molecular dynamics simulation of complex multiphase flow on a computer cluster with GPUs
Institute of Scientific and Technical Information of China (English)
CHEN Fei-Guo; GE Wei; LI Jing-Hai
2009-01-01
Compute Unified Device Architecture (CUDA) was used to design and implement molecular dynamics (MD) simulations on graphics processing units (GPU). With an NVIDIA Tesla C870, a 20-60 fold speedup over that of one core of the Intel Xeon 5430 CPU was achieved, reaching up to 150 Gflopa. MD simulation of cavity flow and particle-bubble interaction in liquid was implemented on multiple GPUs using a message passing interface (MPI). Up to 200 GPUs were tested on a special network topology, which achieves good scalability. The capability of GPU clusters for large-scale molecular dynamics simulation of meso-scale flow behavior was, therefore, uncovered.
Molecular dynamics simulation of complex multiphase flow on a computer cluster with GPUs
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
Compute Unified Device Architecture (CUDA) was used to design and implement molecular dynamics (MD) simulations on graphics processing units (GPU). With an NVIDIA Tesla C870, a 20-60 fold speedup over that of one core of the Intel Xeon 5430 CPU was achieved, reaching up to 150 Gflops. MD simulation of cavity flow and particle-bubble interaction in liquid was implemented on multiple GPUs using a message passing interface (MPI). Up to 200 GPUs were tested on a special network topology, which achieves good scalability. The capability of GPU clusters for large-scale molecular dynamics simulation of meso-scale flow behavior was, therefore, uncovered.
BEAMR: An interactive graphic computer program for design of charged particle beam transport systems
Leonard, R. F.; Giamati, C. C.
1973-01-01
A computer program for a PDP-15 is presented which calculates, to first order, the characteristics of charged-particle beam as it is transported through a sequence of focusing and bending magnets. The maximum dimensions of the beam envelope normal to the transport system axis are continuously plotted on an oscilloscope as a function of distance along the axis. Provision is made to iterate the calculation by changing the types of magnets, their positions, and their field strengths. The program is especially useful for transport system design studies because of the ease and rapidity of altering parameters from panel switches. A typical calculation for a system with eight elements is completed in less than 10 seconds. An IBM 7094 version containing more-detailed printed output but no oscilloscope display is also presented.
Meshfree methods for computational fluid dynamics
Jícha M.; Čermák L.; Niedoba P.
2013-01-01
The paper deals with the convergence problem of the SPH (Smoothed Particle Hydrodynamics) meshfree method for the solution of fluid dynamics tasks. In the introductory part, fundamental aspects of mesh- free methods, their definition, computational approaches and classification are discussed. In the following part, the methods of local integral representation, where SPH belongs are analyzed and specifically the method RKPM (Reproducing Kernel Particle Method) is described. In the contribution...
Delaunay triangulation and computational fluid dynamics meshes
Posenau, Mary-Anne K.; Mount, David M.
1992-01-01
In aerospace computational fluid dynamics (CFD) calculations, the Delaunay triangulation of suitable quadrilateral meshes can lead to unsuitable triangulated meshes. Here, we present case studies which illustrate the limitations of using structured grid generation methods which produce points in a curvilinear coordinate system for subsequent triangulations for CFD applications. We discuss conditions under which meshes of quadrilateral elements may not produce a Delaunay triangulation suitable for CFD calculations, particularly with regard to high aspect ratio, skewed quadrilateral elements.
Computational fluid dynamics in ventilation design
Allard, Francis; Awbi, Hazim B; Davidson, Lars; Schälin, Alois
2007-01-01
CFD-calculations have been rapidly developed to a powerful tool for the analysis of air pollution distribution in various spaces. However, the user of CFD-calculation should be aware of the basic principles of calculations and specifically the boundary conditions. Computational Fluid Dynamics (CFD) – in Ventilation Design models is written by a working group of highly qualified international experts representing research, consulting and design.
Colour in visualisation for computational fluid dynamics
2006-01-01
Colour is used in computational fluid dynamic (CFD) simulations in two key ways. First it is used to visualise the geometry and allow the engineers to be confident that the model constructed is a good representation of the engineering situation. Once an analysis has been completed, colour is used in post-processing the data from the simulations to illustrate the complex fluid mechanic phenomena under investigation. This paper describes these two uses of colour and provides some examples to il...
Application of parallel computing to robot dynamics
Schäfer, Peter; Schiehlen, Werner
1993-01-01
In this paper an approach for the application of parallel processing to the dynamic analysis of robots based on the multibody system method is presented. The inherent structure of the symbolic equations of motion is used for partitioning those into independent modules for concurrent evaluation. The applied strategies for parallelization include the parallel evaluation of subsystem equations and the parallel computation of the inertia matrix along with its factorization, and of the force vecto...
Computational Particle Dynamic Simulations on Multicore Processors (CPDMu) Final Report Phase I
Energy Technology Data Exchange (ETDEWEB)
Schmalz, Mark S
2011-07-24
Statement of Problem - Department of Energy has many legacy codes for simulation of computational particle dynamics and computational fluid dynamics applications that are designed to run on sequential processors and are not easily parallelized. Emerging high-performance computing architectures employ massively parallel multicore architectures (e.g., graphics processing units) to increase throughput. Parallelization of legacy simulation codes is a high priority, to achieve compatibility, efficiency, accuracy, and extensibility. General Statement of Solution - A legacy simulation application designed for implementation on mainly-sequential processors has been represented as a graph G. Mathematical transformations, applied to G, produce a graph representation {und G} for a high-performance architecture. Key computational and data movement kernels of the application were analyzed/optimized for parallel execution using the mapping G {yields} {und G}, which can be performed semi-automatically. This approach is widely applicable to many types of high-performance computing systems, such as graphics processing units or clusters comprised of nodes that contain one or more such units. Phase I Accomplishments - Phase I research decomposed/profiled computational particle dynamics simulation code for rocket fuel combustion into low and high computational cost regions (respectively, mainly sequential and mainly parallel kernels), with analysis of space and time complexity. Using the research team's expertise in algorithm-to-architecture mappings, the high-cost kernels were transformed, parallelized, and implemented on Nvidia Fermi GPUs. Measured speedups (GPU with respect to single-core CPU) were approximately 20-32X for realistic model parameters, without final optimization. Error analysis showed no loss of computational accuracy. Commercial Applications and Other Benefits - The proposed research will constitute a breakthrough in solution of problems related to efficient
1990-01-01
A mathematician, David R. Hedgley, Jr. developed a computer program that considers whether a line in a graphic model of a three-dimensional object should or should not be visible. Known as the Hidden Line Computer Code, the program automatically removes superfluous lines and displays an object from a specific viewpoint, just as the human eye would see it. An example of how one company uses the program is the experience of Birdair which specializes in production of fabric skylights and stadium covers. The fabric called SHEERFILL is a Teflon coated fiberglass material developed in cooperation with DuPont Company. SHEERFILL glazed structures are either tension structures or air-supported tension structures. Both are formed by patterned fabric sheets supported by a steel or aluminum frame or cable network. Birdair uses the Hidden Line Computer Code, to illustrate a prospective structure to an architect or owner. The program generates a three- dimensional perspective with the hidden lines removed. This program is still used by Birdair and continues to be commercially available to the public.
Performance Assessment of Three Rendering Engines in 3D Computer Graphics Software
Directory of Open Access Journals (Sweden)
Žan Vidmar
2015-03-01
Full Text Available The aim of the research was the determination of testing conditions and visual and numerical evaluation of renderings made with three different rendering engines in Maya software, which is widely used for educational and computer art purposes. In the theoretical part the overview of light phenomena and their simulation in virtual space is presented. This is followed by a detailed presentation of the main rendering methods and the results and limitations of their applications to 3D objects. At the end of the theoretical part the importance of a proper testing scene and especially the role of Cornell box are explained. In the experimental part the terms and conditions as well as hardware and software used for the research are presented. This is followed by a description of the procedures, where we focused on the rendering quality and time, which enabled the comparison of settings of different render engines and determination of conditions for further rendering of testing scenes. The experimental part continued with rendering a variety of simple virtual scenes including Cornell box and virtual object with different materials and colours. Apart from visual evaluation, which was the starting point for comparison of renderings, a procedure for numerical estimation and colour deviations of renderings using the selected regions of interest in the final images is presented.
Graphics-System Color-Code Interface
Tulppo, J. S.
1982-01-01
Circuit originally developed for a flight simulator interfaces a computer graphics system with color monitor. Subsystem is intended for particular display computer (AGT-130, ADAGE Graphics Terminal) and specific color monitor (beam penetration tube--Penetron). Store-and-transmit channel is one of five in graphics/color-monitor interface. Adding 5-bit color code to existing graphics programs requires minimal programing effort.
Suh, Joohyung; Ma, Kevin; Le, Anh
2011-03-01
Multiple Sclerosis (MS) is a disease which is caused by damaged myelin around axons of the brain and spinal cord. Currently, MR Imaging is used for diagnosis, but it is very highly variable and time-consuming since the lesion detection and estimation of lesion volume are performed manually. For this reason, we developed a CAD (Computer Aided Diagnosis) system which would assist segmentation of MS to facilitate physician's diagnosis. The MS CAD system utilizes K-NN (k-nearest neighbor) algorithm to detect and segment the lesion volume in an area based on the voxel. The prototype MS CAD system was developed under the MATLAB environment. Currently, the MS CAD system consumes a huge amount of time to process data. In this paper we will present the development of a second version of MS CAD system which has been converted into C/C++ in order to take advantage of the GPU (Graphical Processing Unit) which will provide parallel computation. With the realization of C/C++ and utilizing the GPU, we expect to cut running time drastically. The paper investigates the conversion from MATLAB to C/C++ and the utilization of a high-end GPU for parallel computing of data to improve algorithm performance of MS CAD.
Computational Fluid Dynamics of rising droplets
Energy Technology Data Exchange (ETDEWEB)
Wagner, Matthew [Lake Superior State University; Francois, Marianne M. [Los Alamos National Laboratory
2012-09-05
The main goal of this study is to perform simulations of droplet dynamics using Truchas, a LANL-developed computational fluid dynamics (CFD) software, and compare them to a computational study of Hysing et al.[IJNMF, 2009, 60:1259]. Understanding droplet dynamics is of fundamental importance in liquid-liquid extraction, a process used in the nuclear fuel cycle to separate various components. Simulations of a single droplet rising by buoyancy are conducted in two-dimensions. Multiple parametric studies are carried out to ensure the problem set-up is optimized. An Interface Smoothing Length (ISL) study and mesh resolution study are performed to verify convergence of the calculations. ISL is a parameter for the interface curvature calculation. Further, wall effects are investigated and checked against existing correlations. The ISL study found that the optimal ISL value is 2.5{Delta}x, with {Delta}x being the mesh cell spacing. The mesh resolution study found that the optimal mesh resolution is d/h=40, for d=drop diameter and h={Delta}x. In order for wall effects on terminal velocity to be insignificant, a conservative wall width of 9d or a nonconservative wall width of 7d can be used. The percentage difference between Hysing et al.[IJNMF, 2009, 60:1259] and Truchas for the velocity profiles vary from 7.9% to 9.9%. The computed droplet velocity and interface profiles are found in agreement with the study. The CFD calculations are performed on multiple cores, using LANL's Institutional High Performance Computing.
Kuo, Chien-Chung; Lu, Hsuan-Lun; Leardini, Alberto; Lu, Tung-Wu; Kuo, Mei-Ying; Hsu, Horng-Chaung
2014-05-01
Morphometry of the bones of the ankle joint is important for the design of joint replacements and their surgical implantations. However, very little three-dimensional (3D) data are available and not a single study has addressed the Chinese population. Fifty-eight fresh frozen Chinese cadaveric ankle specimens, 26 females, and 32 males, were CT-scanned in the neutral position and their 3D computer graphics-based models were reconstructed. The 3D morphology of the distal tibia/fibula segment and the full talus was analyzed by measuring 31 parameters, defining the relevant dimensions, areas, and volumes from the models. The measurements were compared statistically between sexes and with previously reported data from Caucasian subjects. The results showed that, within a general similarity of ankle morphology between the current Chinese and previous Caucasian subjects groups, there were significant differences in 9 out of the 31 parameters analyzed. From a quantitative comparison with available prostheses designed for the Caucasian population, few of these designs have both tibial and talar components suitable in dimension for the Chinese population. The current data will be helpful for the sizing, design, and surgical positioning of ankle replacements and for surgical instruments, especially for the Chinese population.
Cickovski, Trevor; Flor, Tiffany; Irving-Sachs, Galen; Novikov, Philip; Parda, James; Narasimhan, Giri
2015-01-01
In order to make multiple copies of a target sequence in the laboratory, the technique of Polymerase Chain Reaction (PCR) requires the design of "primers", which are short fragments of nucleotides complementary to the flanking regions of the target sequence. If the same primer is to amplify multiple closely related target sequences, then it is necessary to make the primers "degenerate", which would allow it to hybridize to target sequences with a limited amount of variability that may have been caused by mutations. However, the PCR technique can only allow a limited amount of degeneracy, and therefore the design of degenerate primers requires the identification of reasonably well-conserved regions in the input sequences. We take an existing algorithm for designing degenerate primers that is based on clustering and parallelize it in a web-accessible software package GPUDePiCt, using a shared memory model and the computing power of Graphics Processing Units (GPUs). We test our implementation on large sets of aligned sequences from the human genome and show a multi-fold speedup for clustering using our hybrid GPU/CPU implementation over a pure CPU approach for these sequences, which consist of more than 7,500 nucleotides. We also demonstrate that this speedup is consistent over larger numbers and longer lengths of aligned sequences.
Pallozzi Lavorante, Luca; Dirk Ebert, Hans
2008-07-01
Tensor3D is a geometric modeling program with the capacity to simulate and visualize in real-time the deformation, specified through a tensor matrix and applied to triangulated models representing geological bodies. 3D visualization allows the study of deformational processes that are traditionally conducted in 2D, such as simple and pure shears. Besides geometric objects that are immediately available in the program window, the program can read other models from disk, thus being able to import objects created with different open-source or proprietary programs. A strain ellipsoid and a bounding box are simultaneously shown and instantly deformed with the main object. The principal axes of strain are visualized as well to provide graphical information about the orientation of the tensor's normal components. The deformed models can also be saved, retrieved later and deformed again, in order to study different steps of progressive strain, or to make this data available to other programs. The shape of stress ellipsoids and the corresponding Mohr circles defined by any stress tensor can also be represented. The application was written using the Visualization ToolKit, a powerful scientific visualization library in the public domain. This development choice, allied to the use of the Tcl/Tk programming language, which is independent on the host computational platform, makes the program a useful tool for the study of geometric deformations directly in three dimensions in teaching as well as research activities.
Dynamical Models for Computer Viruses Propagation
Directory of Open Access Journals (Sweden)
José R. C. Piqueira
2008-01-01
Full Text Available Nowadays, digital computer systems and networks are the main engineering tools, being used in planning, design, operation, and control of all sizes of building, transportation, machinery, business, and life maintaining devices. Consequently, computer viruses became one of the most important sources of uncertainty, contributing to decrease the reliability of vital activities. A lot of antivirus programs have been developed, but they are limited to detecting and removing infections, based on previous knowledge of the virus code. In spite of having good adaptation capability, these programs work just as vaccines against diseases and are not able to prevent new infections based on the network state. Here, a trial on modeling computer viruses propagation dynamics relates it to other notable events occurring in the network permitting to establish preventive policies in the network management. Data from three different viruses are collected in the Internet and two different identification techniques, autoregressive and Fourier analyses, are applied showing that it is possible to forecast the dynamics of a new virus propagation by using the data collected from other viruses that formerly infected the network.
Fundamental algorithms in computational fluid dynamics
Pulliam, Thomas H
2014-01-01
Intended as a textbook for courses in computational fluid dynamics at the senior undergraduate or graduate level, this book is a follow-up to the book Fundamentals of Computational Fluid Dynamics by the same authors, which was published in the series Scientific Computation in 2001. Whereas the earlier book concentrated on the analysis of numerical methods applied to model equations, this new book concentrates on algorithms for the numerical solution of the Euler and Navier-Stokes equations. It focuses on some classical algorithms as well as the underlying ideas based on the latest methods. A key feature of the book is the inclusion of programming exercises at the end of each chapter based on the numerical solution of the quasi-one-dimensional Euler equations and the shock-tube problem. These exercises can be included in the context of a typical course, and sample solutions are provided in each chapter, so readers can confirm that they have coded the algorithms correctly.
Fazanaro, Filipe I.; Soriano, Diogo C.; Suyama, Ricardo; Madrid, Marconi K.; Oliveira, José Raimundo de; Muñoz, Ignacio Bravo; Attux, Romis
2016-08-01
The characterization of nonlinear dynamical systems and their attractors in terms of invariant measures, basins of attractions and the structure of their vector fields usually outlines a task strongly related to the underlying computational cost. In this work, the practical aspects related to the use of parallel computing - specially the use of Graphics Processing Units (GPUS) and of the Compute Unified Device Architecture (CUDA) - are reviewed and discussed in the context of nonlinear dynamical systems characterization. In this work such characterization is performed by obtaining both local and global Lyapunov exponents for the classical forced Duffing oscillator. The local divergence measure was employed by the computation of the Lagrangian Coherent Structures (LCSS), revealing the general organization of the flow according to the obtained separatrices, while the global Lyapunov exponents were used to characterize the attractors obtained under one or more bifurcation parameters. These simulation sets also illustrate the required computation time and speedup gains provided by different parallel computing strategies, justifying the employment and the relevance of GPUS and CUDA in such extensive numerical approach. Finally, more than simply providing an overview supported by a representative set of simulations, this work also aims to be a unified introduction to the use of the mentioned parallel computing tools in the context of nonlinear dynamical systems, providing codes and examples to be executed in MATLAB and using the CUDA environment, something that is usually fragmented in different scientific communities and restricted to specialists on parallel computing strategies.
Computational fluid dynamics: Transition to design applications
Bradley, R. G.; Bhateley, I. C.; Howell, G. A.
1987-01-01
The development of aerospace vehicles, over the years, was an evolutionary process in which engineering progress in the aerospace community was based, generally, on prior experience and data bases obtained through wind tunnel and flight testing. Advances in the fundamental understanding of flow physics, wind tunnel and flight test capability, and mathematical insights into the governing flow equations were translated into improved air vehicle design. The modern day field of Computational Fluid Dynamics (CFD) is a continuation of the growth in analytical capability and the digital mathematics needed to solve the more rigorous form of the flow equations. Some of the technical and managerial challenges that result from rapidly developing CFD capabilites, some of the steps being taken by the Fort Worth Division of General Dynamics to meet these challenges, and some of the specific areas of application for high performance air vehicles are presented.
Computational fluid dynamics in cardiovascular disease.
Lee, Byoung-Kwon
2011-08-01
Computational fluid dynamics (CFD) is a mechanical engineering field for analyzing fluid flow, heat transfer, and associated phenomena, using computer-based simulation. CFD is a widely adopted methodology for solving complex problems in many modern engineering fields. The merit of CFD is developing new and improved devices and system designs, and optimization is conducted on existing equipment through computational simulations, resulting in enhanced efficiency and lower operating costs. However, in the biomedical field, CFD is still emerging. The main reason why CFD in the biomedical field has lagged behind is the tremendous complexity of human body fluid behavior. Recently, CFD biomedical research is more accessible, because high performance hardware and software are easily available with advances in computer science. All CFD processes contain three main components to provide useful information, such as pre-processing, solving mathematical equations, and post-processing. Initial accurate geometric modeling and boundary conditions are essential to achieve adequate results. Medical imaging, such as ultrasound imaging, computed tomography, and magnetic resonance imaging can be used for modeling, and Doppler ultrasound, pressure wire, and non-invasive pressure measurements are used for flow velocity and pressure as a boundary condition. Many simulations and clinical results have been used to study congenital heart disease, heart failure, ventricle function, aortic disease, and carotid and intra-cranial cerebrovascular diseases. With decreasing hardware costs and rapid computing times, researchers and medical scientists may increasingly use this reliable CFD tool to deliver accurate results. A realistic, multidisciplinary approach is essential to accomplish these tasks. Indefinite collaborations between mechanical engineers and clinical and medical scientists are essential. CFD may be an important methodology to understand the pathophysiology of the development and
Computational dynamics of acoustically driven microsphere systems.
Glosser, Connor; Piermarocchi, Carlo; Li, Jie; Dault, Dan; Shanker, B
2016-01-01
We propose a computational framework for the self-consistent dynamics of a microsphere system driven by a pulsed acoustic field in an ideal fluid. Our framework combines a molecular dynamics integrator describing the dynamics of the microsphere system with a time-dependent integral equation solver for the acoustic field that makes use of fields represented as surface expansions in spherical harmonic basis functions. The presented approach allows us to describe the interparticle interaction induced by the field as well as the dynamics of trapping in counter-propagating acoustic pulses. The integral equation formulation leads to equations of motion for the microspheres describing the effect of nondissipative drag forces. We show (1) that the field-induced interactions between the microspheres give rise to effective dipolar interactions, with effective dipoles defined by their velocities and (2) that the dominant effect of an ultrasound pulse through a cloud of microspheres gives rise mainly to a translation of the system, though we also observe both expansion and contraction of the cloud determined by the initial system geometry.
Colour in visualisation for computational fluid dynamics
Kinnear, David; Atherton, Mark; Collins, Michael; Dokhan, Jason; Karayiannis, Tassos
2006-06-01
Colour is used in computational fluid dynamic (CFD) simulations in two key ways. First it is used to visualise the geometry and allow the engineer to be confident that the model constructed is a good representation of the engineering situation. Once an analysis has been completed, colour is used in post-processing the data from the simulations to illustrate the complex fluid mechanic phenomena under investigation. This paper describes these two uses of colour and provides some examples to illustrate the key visualisation approaches used in CFD.
Domain decomposition algorithms and computational fluid dynamics
Chan, Tony F.
1988-01-01
Some of the new domain decomposition algorithms are applied to two model problems in computational fluid dynamics: the two-dimensional convection-diffusion problem and the incompressible driven cavity flow problem. First, a brief introduction to the various approaches of domain decomposition is given, and a survey of domain decomposition preconditioners for the operator on the interface separating the subdomains is then presented. For the convection-diffusion problem, the effect of the convection term and its discretization on the performance of some of the preconditioners is discussed. For the driven cavity problem, the effectiveness of a class of boundary probe preconditioners is examined.
Verification of computer users using keystroke dynamics.
Obaidat, M S; Sadoun, B
1997-01-01
This paper presents techniques to verify the identity of computer users using the keystroke dynamics of computer user's login string as characteristic patterns using pattern recognition and neural network techniques. This work is a continuation of our previous work where only interkey times were used as features for identifying computer users. In this work we used the key hold times for classification and then compared the performance with the former interkey time-based technique. Then we use the combined interkey and hold times for the identification process. We applied several neural network and pattern recognition algorithms for verifying computer users as they type their password phrases. It was found that hold times are more effective than interkey times and the best identification performance was achieved by using both time measurements. An identification accuracy of 100% was achieved when the combined hold and intekey time-based approach were considered as features using the fuzzy ARTMAP, radial basis function networks (RBFN), and learning vector quantization (LVQ) neural network paradigms. Other neural network and classical pattern algorithms such as backpropagation with a sigmoid transfer function (BP, Sigm), hybrid sum-of-products (HSOP), sum-of-products (SOP), potential function and Bayes' rule algorithms gave moderate performance.
Computer Graphics in Cinematography
Polozuns, Aleksandrs
2013-01-01
The purpose of this thesis was to cover the major characteristics about different techniques presently used in the field of CG and visual effects by giving a variety of examples from the famous movies. Moreover, the history of visual effects and CGI, and how the development process of it changed the industry of cinematography were studied. The practi-cal part of this study is dedicated to analyzing what modern software are the most popular ones among professionals. Several studios were survey...
Computer Graphics Research Laboratory
1994-01-31
row represents the ’within- turn signal ’: Gilbert has the turn but is pausing; he looks at George. The next frame shows the ’speaker-continuation...taking systems [13]. In the control sub-network we consider two types of signal in the turn-taking system: 1. End-of-Turn (Speaker- Turn - Signal ): the...Speaker-Within-Turn. In such a case, the speaker turns her head away from tlie listener. If the speaker doesn’t emit a within- turn - signal , the listener
Direct modeling for computational fluid dynamics
Xu, Kun
2015-06-01
All fluid dynamic equations are valid under their modeling scales, such as the particle mean free path and mean collision time scale of the Boltzmann equation and the hydrodynamic scale of the Navier-Stokes (NS) equations. The current computational fluid dynamics (CFD) focuses on the numerical solution of partial differential equations (PDEs), and its aim is to get the accurate solution of these governing equations. Under such a CFD practice, it is hard to develop a unified scheme that covers flow physics from kinetic to hydrodynamic scales continuously because there is no such governing equation which could make a smooth transition from the Boltzmann to the NS modeling. The study of fluid dynamics needs to go beyond the traditional numerical partial differential equations. The emerging engineering applications, such as air-vehicle design for near-space flight and flow and heat transfer in micro-devices, do require further expansion of the concept of gas dynamics to a larger domain of physical reality, rather than the traditional distinguishable governing equations. At the current stage, the non-equilibrium flow physics has not yet been well explored or clearly understood due to the lack of appropriate tools. Unfortunately, under the current numerical PDE approach, it is hard to develop such a meaningful tool due to the absence of valid PDEs. In order to construct multiscale and multiphysics simulation methods similar to the modeling process of constructing the Boltzmann or the NS governing equations, the development of a numerical algorithm should be based on the first principle of physical modeling. In this paper, instead of following the traditional numerical PDE path, we introduce direct modeling as a principle for CFD algorithm development. Since all computations are conducted in a discretized space with limited cell resolution, the flow physics to be modeled has to be done in the mesh size and time step scales. Here, the CFD is more or less a direct
Anacleto, Osvaldo; Queen, Catriona; Albers, Casper J.
2013-01-01
Traffic flow data are routinely collected for many networks worldwide. These invariably large data sets can be used as part of a traffic management system, for which good traffic flow forecasting models are crucial. The linear multiregression dynamic model (LMDM) has been shown to be promising for f
Miranda, Diogo Julien; Wen, Chao Lung
2017-07-18
Preliminary studies suggest the need of a global vision in academic reform, leading to education re-invention. This would include problem-based education using transversal topics, developing of thinking skills, social interaction, and information-processing skills. We aimed to develop a new educational model in health with modular components to be broadcast and applied as a tele-education course. We developed a systematic model based on a "Skills and Goals Matrix" to adapt scientific contents on fictional screenplays, three-dimensional (3D) computer graphics of the human body, and interactive documentaries. We selected 13 topics based on youth vulnerabilities in Brazil to be disseminated through a television show with 15 episodes. We developed scientific content for each theme, naturally inserting it into screenplays, together with 3D sequences and interactive documentaries. The modular structure was then adapted to a distance-learning course. The television show was broadcast on national television for two consecutive years to an estimated audience of 30 million homes, and ever since on an Internet Protocol Television (IPTV) channel. It was also reorganized as a tele-education course for 2 years, reaching 1,180 subscriptions from all 27 Brazilian states, resulting in 240 graduates. Positive results indicate the feasibility, acceptability, and effectiveness of a model of modular entertainment audio-visual productions using health and education integrated concepts. This structure also allowed the model to be interconnected with other sources and applied as tele-education course, educating, informing, and stimulating the behavior change. Future works should reinforce this joint structure of telehealth, communication, and education.
Computing dynamic classification images from correlation maps.
Lu, Hongjing; Liu, Zili
2006-05-22
We used Pearson's correlation to compute dynamic classification images of biological motion in a point-light display. Observers discriminated whether a human figure that was embedded in dynamic white Gaussian noise was walking forward or backward. Their responses were correlated with the Gaussian noise fields frame by frame, across trials. The resultant correlation map gave rise to a sequence of dynamic classification images that were clearer than either the standard method of A. J. Ahumada and J. Lovell (1971) or the optimal weighting method of R. F. Murray, P. J. Bennett, and A. B. Sekuler (2002). Further, the correlation coefficients of all the point lights were similar to each other when overlapping pixels between forward and backward walkers were excluded. This pattern is consistent with the hypothesis that the point-light walker is represented in a global manner, as opposed to a fixed subset of point lights being more important than others. We conjecture that the superior performance of the correlation map may reflect inherent nonlinearities in processing biological motion, which are incompatible with the assumptions underlying the previous methods.
Thompson, John
2009-01-01
Graphic storytelling is a medium that allows students to make and share stories, while developing their art communication skills. American comics today are more varied in genre, approach, and audience than ever before. When considering the impact of Japanese manga on the youth, graphic storytelling emerges as a powerful player in pop culture. In…
Thompson, John
2009-01-01
Graphic storytelling is a medium that allows students to make and share stories, while developing their art communication skills. American comics today are more varied in genre, approach, and audience than ever before. When considering the impact of Japanese manga on the youth, graphic storytelling emerges as a powerful player in pop culture. In…
GANDALF: Graphical Astrophysics code for N-body Dynamics And Lagrangian Fluids
Hubber, David; Rosotti, Giovanni
2016-02-01
GANDALF, a successor to SEREN (ascl:1102.010), is a hybrid self-gravitating fluid dynamics and collisional N-body code primarily designed for investigating star formation and planet formation problems. GANDALF uses various implementations of Smoothed Particle Hydrodynamics (SPH) to perform hydrodynamical simulations of gas clouds undergoing gravitational collapse to form new stars (or other objects), and can perform simulations of pure N-body dynamics using high accuracy N-body integrators, model the intermediate phase of cluster evolution, and provide visualizations via its python interface as well as interactive simulations. Although based on many of the SEREN routines, GANDALF has been largely re-written from scratch in C++ using more optimal algorithms and data structures.
Display of Dynamic, Volume Graphic Images by Holographic Voxel Projection. Initial Investigation
1993-04-29
REFERENCE S 1. Veron, H., D. Southard, J. Leger, and J. Conway, " 3D Displays for Battle Management," The MITRE Corporation, Bedford, MA, 01730...published as RADC-TR-90-46 (April 1990). 2. Wilson, A., "At SID, Lasers Put New Spin on 3D Displays," ESD: The Electronic System Design Magazine, August...34Electronic Display System for Computational Holography," SPIE, Vol 1212, pp. 325-333, (January 1990). 5. Meacham, G., " Autostereoscopic Displays - Past
Institute of Scientific and Technical Information of China (English)
无
2004-01-01
1. The 13th International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision'2005, University of West Bohemia, Campus-Bory Plzen (very close to Prague, the capital of the Czech Republic)Czech Republic, January 31 - February 4, 2005. http://wscg.zcu.cz, skala@kiv.zcu.cz
Dastane, A; Vaidyanathan, T K; Vaidyanathan, J; Mehra, R; Hesby, R
1996-01-01
It is necessary to visualize and reconstruct tissue anatomic surfaces accurately for a variety of oral rehabilitation applications such as surface wear characterization and automated fabrication of dental restorations, accuracy of reproduction of impression and die materials, etc. In this investigation, a 3-D digitization and computer-graphic system was developed for surface characterization. The hardware consists of a profiler assembly for digitization in an MTS biomechanical test system with an artificial mouth, an IBM PS/2 computer model 70 for data processing and a Hewlett-Packard laser printer for hardcopy outputs. The software used includes a commercially available Surfer 3-D graphics package, a public domain data-fitting alignment software and an inhouse Pascal program for intercommunication plus some other limited tasks. Surfaces were digitized before and after rotation by angular displacement, the digital data were interpolated by Surfer to provide a data grid and the surfaces were computer graphically reconstructed: Misaligned surfaces were aligned by the data-fitting alignment software under different choices of parameters. The effect of different interpolation parameters (e.g. grid size, method of interpolation) and extent of rotation on the alignment accuracy was determined. The results indicate that improved alignment accuracy results from optimization of interpolation parameters and minimization of the initial misorientation between the digitized surfaces. The method provides important advantages for surface reconstruction and visualization, such as overlay of sequentially generated surfaces and accurate alignment of pairs of surfaces with small misalignment.
High Fidelity Adiabatic Quantum Computation via Dynamical Decoupling
Quiroz, Gregory
2012-01-01
We introduce high-order dynamical decoupling strategies for open system adiabatic quantum computation. Our numerical results demonstrate that a judicious choice of high-order dynamical decoupling method, in conjunction with an encoding which allows computation to proceed alongside decoupling, can dramatically enhance the fidelity of adiabatic quantum computation in spite of decoherence.
A graphical interface based model for wind turbine drive train dynamics
Energy Technology Data Exchange (ETDEWEB)
Manwell, J.F.; McGowan, J.G.; Abdulwahid, U.; Rogers, A. [Univ. of Massachusetts, Amherst, MA (United States); McNiff, B. [McNiff Light Industry, Blue Hill, ME (United States)
1996-12-31
This paper presents a summary of a wind turbine drive train dynamics code that has been under development at the University of Massachusetts, under National Renewable Energy Laboratory (NREL) support. The code is intended to be used to assist in the proper design and selection of drive train components. This work summarizes the development of the equations of motion for the model, and discusses the method of solution. In addition, a number of comparisons with analytical solutions and experimental field data are given. The summary includes conclusions and suggestions for future work on the model. 13 refs., 10 figs.
Kirk, David
1994-01-01
This sequel to Graphics Gems (Academic Press, 1990), and Graphics Gems II (Academic Press, 1991) is a practical collection of computer graphics programming tools and techniques. Graphics Gems III contains a larger percentage of gems related to modeling and rendering, particularly lighting and shading. This new edition also covers image processing, numerical and programming techniques, modeling and transformations, 2D and 3D geometry and algorithms,ray tracing and radiosity, rendering, and more clever new tools and tricks for graphics programming. Volume III also includes a
Domain decomposition algorithms and computation fluid dynamics
Chan, Tony F.
1988-01-01
In the past several years, domain decomposition was a very popular topic, partly motivated by the potential of parallelization. While a large body of theory and algorithms were developed for model elliptic problems, they are only recently starting to be tested on realistic applications. The application of some of these methods to two model problems in computational fluid dynamics are investigated. Some examples are two dimensional convection-diffusion problems and the incompressible driven cavity flow problem. The construction and analysis of efficient preconditioners for the interface operator to be used in the iterative solution of the interface solution is described. For the convection-diffusion problems, the effect of the convection term and its discretization on the performance of some of the preconditioners is discussed. For the driven cavity problem, the effectiveness of a class of boundary probe preconditioners is discussed.
Artificial Intelligence In Computational Fluid Dynamics
Vogel, Alison Andrews
1991-01-01
Paper compares four first-generation artificial-intelligence (Al) software systems for computational fluid dynamics. Includes: Expert Cooling Fan Design System (EXFAN), PAN AIR Knowledge System (PAKS), grid-adaptation program MITOSIS, and Expert Zonal Grid Generation (EZGrid). Focuses on knowledge-based ("expert") software systems. Analyzes intended tasks, kinds of knowledge possessed, magnitude of effort required to codify knowledge, how quickly constructed, performances, and return on investment. On basis of comparison, concludes Al most successful when applied to well-formulated problems solved by classifying or selecting preenumerated solutions. In contrast, application of Al to poorly understood or poorly formulated problems generally results in long development time and large investment of effort, with no guarantee of success.
Lectures series in computational fluid dynamics
Thompson, Kevin W.
1987-01-01
The lecture notes cover the basic principles of computational fluid dynamics (CFD). They are oriented more toward practical applications than theory, and are intended to serve as a unified source for basic material in the CFD field as well as an introduction to more specialized topics in artificial viscosity and boundary conditions. Each chapter in the test is associated with a videotaped lecture. The basic properties of conservation laws, wave equations, and shock waves are described. The duality of the conservation law and wave representations is investigated, and shock waves are examined in some detail. Finite difference techniques are introduced for the solution of wave equations and conservation laws. Stability analysis for finite difference approximations are presented. A consistent description of artificial viscosity methods are provided. Finally, the problem of nonreflecting boundary conditions are treated.
Artificial Intelligence In Computational Fluid Dynamics
Vogel, Alison Andrews
1991-01-01
Paper compares four first-generation artificial-intelligence (Al) software systems for computational fluid dynamics. Includes: Expert Cooling Fan Design System (EXFAN), PAN AIR Knowledge System (PAKS), grid-adaptation program MITOSIS, and Expert Zonal Grid Generation (EZGrid). Focuses on knowledge-based ("expert") software systems. Analyzes intended tasks, kinds of knowledge possessed, magnitude of effort required to codify knowledge, how quickly constructed, performances, and return on investment. On basis of comparison, concludes Al most successful when applied to well-formulated problems solved by classifying or selecting preenumerated solutions. In contrast, application of Al to poorly understood or poorly formulated problems generally results in long development time and large investment of effort, with no guarantee of success.
Open Skies Project Computational Fluid Dynamic Analysis
1994-03-01
SGI Silicon Graphics Inc. SLNS Slender-Layer Navier-Stokes TESTW/FFX 4950th Test Wing’s Experimental Flight Test Division TFI TransFinite Interpolation...There were a few negative cells indicated i. the fine 3-D grid, near the window corners, that the Lockheed TransFinite Interpolation (TFI), and
Bioreactor Studies and Computational Fluid Dynamics
Singh, H.; Hutmacher, D. W.
The hydrodynamic environment “created” by bioreactors for the culture of a tissue engineered construct (TEC) is known to influence cell migration, proliferation and extra cellular matrix production. However, tissue engineers have looked at bioreactors as black boxes within which TECs are cultured mainly by trial and error, as the complex relationship between the hydrodynamic environment and tissue properties remains elusive, yet is critical to the production of clinically useful tissues. It is well known in the chemical and biotechnology field that a more detailed description of fluid mechanics and nutrient transport within process equipment can be achieved via the use of computational fluid dynamics (CFD) technology. Hence, the coupling of experimental methods and computational simulations forms a synergistic relationship that can potentially yield greater and yet, more cohesive data sets for bioreactor studies. This review aims at discussing the rationale of using CFD in bioreactor studies related to tissue engineering, as fluid flow processes and phenomena have direct implications on cellular response such as migration and/or proliferation. We conclude that CFD should be seen by tissue engineers as an invaluable tool allowing us to analyze and visualize the impact of fluidic forces and stresses on cells and TECs.
Computational Fluid Dynamics in Hypersonic Aerothermodynamics
Directory of Open Access Journals (Sweden)
Krishnendu Sinha
2010-10-01
Full Text Available Hypersonic flows are characterised by high Mach number and high total enthalpy. An elevated temperature often results in thermo-chemical reactions in the gas, which p lay a major role in aerothermodynamic characterisation of high-speed aerospace vehicles. Hypersonic flows in propulsion components are usually turbulent, resulting in additional effects. Computational simulation of such flows, therefore, need to account for a range of physical phenomena. Further, the numerical challenges involved in resolving strong gradients and discontinuities add to the complexity of computational fluid dynamics (CFD simulation. In this article, physical modelling and numerical methodology-related issues involved in hypersonic flow simulation are highlighted. State-of-the-art CFD challenges are discussed in the context of two prominent applications-the flow in a scramjet inlet and the flow field around a re-entry capsule.Defence Science Journal, 2010, 60(6, pp.663-671, DOI:http://dx.doi.org/10.14429/dsj.60.604
Energy Technology Data Exchange (ETDEWEB)
Stevens, E.J.; McNeilly, G.S.
1994-03-01
The existing National Center for Atmospheric Research (NCAR) code in the Hamburg Oceanic Carbon Cycle Circulation Model and the Hamburg Large-Scale Geostrophic Ocean General Circulation Model was modernized and reduced in size while still producing an equivalent end result. A reduction in the size of the existing code from more than 50,000 lines to approximately 7,500 lines in the new code has made the new code much easier to maintain. The existing code in Hamburg model uses legacy NCAR (including even emulated CALCOMP subrountines) graphics to display graphical output. The new code uses only current (version 3.1) NCAR subrountines.
Energy Technology Data Exchange (ETDEWEB)
Stevens, E.J.; McNeilly, G.S.
1994-03-01
The existing National Center for Atmospheric Research (NCAR) code in the Hamburg Oceanic Carbon Cycle Circulation Model and the Hamburg Large-Scale Geostrophic Ocean General Circulation Model was modernized and reduced in size while still producing an equivalent end result. A reduction in the size of the existing code from more than 50,000 lines to approximately 7,500 lines in the new code has made the new code much easier to maintain. The existing code in Hamburg model uses legacy NCAR (including even emulated CALCOMP subrountines) graphics to display graphical output. The new code uses only current (version 3.1) NCAR subrountines.
Graphics shaders theory and practice
Bailey, Mike
2011-01-01
Graphics Shaders: Theory and Practice is intended for a second course in computer graphics at the undergraduate or graduate level, introducing shader programming in general, but focusing on the GLSL shading language. While teaching how to write programmable shaders, the authors also teach and reinforce the fundamentals of computer graphics. The second edition has been updated to incorporate changes in the OpenGL API (OpenGL 4.x and GLSL 4.x0) and also has a chapter on the new tessellation shaders, including many practical examples. The book starts with a quick review of the graphics pipeline,
DEFF Research Database (Denmark)
Breiting, Søren
2002-01-01
Introduktion til 'graphic review' som en metode til at føre forståelse fra en undervisngsgang til den næste i læreruddannelse og grundskole.......Introduktion til 'graphic review' som en metode til at føre forståelse fra en undervisngsgang til den næste i læreruddannelse og grundskole....
Glassner, Andrew S
1993-01-01
""The GRAPHICS GEMS Series"" was started in 1990 by Andrew Glassner. The vision and purpose of the Series was - and still is - to provide tips, techniques, and algorithms for graphics programmers. All of the gems are written by programmers who work in the field and are motivated by a common desire to share interesting ideas and tools with their colleagues. Each volume provides a new set of innovative solutions to a variety of programming problems.
Institute of Scientific and Technical Information of China (English)
陈凯晴
2011-01-01
Dynamic Image Design is a comprehensive art digital design,the application of different types and elements of design,combining live action,visual effects,2D/3D animation,graphic design,typography, interactive design and other areas.Dynamic images are usually designed to show the electronic media technology, with the static graphic design difference is that the performance will change over time.ln the era of rapid development of computer technology, video design is leading the trend of new media design.%动态影像设计是一种数字设计领域的综合艺术，应用了不同的设计类别与元素，融合了实景拍摄、视觉特效、2D／3D动画、图形设计、字体设计、互动设计等各种领域。动态影像设计通常以电子媒体科技展现，跟静态的图像设计的区别是在于，表现是否会随时间而改变。在电脑技术高速发展的时代，动态影像设计正引领着新媒体设计的潮流。
Computational fluid dynamics modelling in cardiovascular medicine.
Morris, Paul D; Narracott, Andrew; von Tengg-Kobligk, Hendrik; Silva Soto, Daniel Alejandro; Hsiao, Sarah; Lungu, Angela; Evans, Paul; Bressloff, Neil W; Lawford, Patricia V; Hose, D Rodney; Gunn, Julian P
2016-01-01
This paper reviews the methods, benefits and challenges associated with the adoption and translation of computational fluid dynamics (CFD) modelling within cardiovascular medicine. CFD, a specialist area of mathematics and a branch of fluid mechanics, is used routinely in a diverse range of safety-critical engineering systems, which increasingly is being applied to the cardiovascular system. By facilitating rapid, economical, low-risk prototyping, CFD modelling has already revolutionised research and development of devices such as stents, valve prostheses, and ventricular assist devices. Combined with cardiovascular imaging, CFD simulation enables detailed characterisation of complex physiological pressure and flow fields and the computation of metrics which cannot be directly measured, for example, wall shear stress. CFD models are now being translated into clinical tools for physicians to use across the spectrum of coronary, valvular, congenital, myocardial and peripheral vascular diseases. CFD modelling is apposite for minimally-invasive patient assessment. Patient-specific (incorporating data unique to the individual) and multi-scale (combining models of different length- and time-scales) modelling enables individualised risk prediction and virtual treatment planning. This represents a significant departure from traditional dependence upon registry-based, population-averaged data. Model integration is progressively moving towards 'digital patient' or 'virtual physiological human' representations. When combined with population-scale numerical models, these models have the potential to reduce the cost, time and risk associated with clinical trials. The adoption of CFD modelling signals a new era in cardiovascular medicine. While potentially highly beneficial, a number of academic and commercial groups are addressing the associated methodological, regulatory, education- and service-related challenges.
基于图像的图形生成系统中的虚拟摄像机模型%An Virtual Camera Models of Image based Computer Graphics
Institute of Scientific and Technical Information of China (English)
王建华; 解凯
2002-01-01
The paper discusses the virtual general cameral model. It gives the approach of 3D reconstruction. Bymeans of the model ,the paper formulates the transformation of the general model into simple standard model in com-pute Vision and graphics.
Binti Shamsuddin, Norsila
Technology advancement and development in a higher learning institution is a chance for students to be motivated to learn in depth in the information technology areas. Students should take hold of the opportunity to blend their skills towards these technologies as preparation for them when graduating. The curriculum itself can rise up the students' interest and persuade them to be directly involved in the evolvement of the technology. The aim of this study is to see how deep is the students' involvement as well as their acceptance towards the adoption of the technology used in Computer Graphics and Image Processing subjects. The study will be towards the Bachelor students in Faculty of Industrial Information Technology (FIIT), Universiti Industri Selangor (UNISEL); Bac. In Multimedia Industry, BSc. Computer Science and BSc. Computer Science (Software Engineering). This study utilizes the new Unified Theory of Acceptance and Use of Technology (UTAUT) to further validate the model and enhance our understanding of the adoption of Computer Graphics and Image Processing Technologies. Four (4) out of eight (8) independent factors in UTAUT will be studied towards the dependent factor.
Dynamic Factor Method of Computing Dynamic Mathematical Model for System Simulation
Institute of Scientific and Technical Information of China (English)
老大中; 吴娟; 杨策; 蒋滋康
2003-01-01
The computational methods of a typical dynamic mathematical model that can describe the differential element and the inertial element for the system simulation are researched. The stability of numerical solutions of the dynamic mathematical model is researched. By means of theoretical analysis, the error formulas, the error sign criteria and the error relationship criterion of the implicit Euler method and the trapezoidal method are given, the dynamic factor affecting the computational accuracy has been found, the formula and the methods of computing the dynamic factor are given. The computational accuracy of the dynamic mathematical model like this can be improved by use of the dynamic factor.
High-throughput all-atom molecular dynamics simulations using distributed computing.
Buch, I; Harvey, M J; Giorgino, T; Anderson, D P; De Fabritiis, G
2010-03-22
Although molecular dynamics simulation methods are useful in the modeling of macromolecular systems, they remain computationally expensive, with production work requiring costly high-performance computing (HPC) resources. We review recent innovations in accelerating molecular dynamics on graphics processing units (GPUs), and we describe GPUGRID, a volunteer computing project that uses the GPU resources of nondedicated desktop and workstation computers. In particular, we demonstrate the capability of simulating thousands of all-atom molecular trajectories generated at an average of 20 ns/day each (for systems of approximately 30 000-80 000 atoms). In conjunction with a potential of mean force (PMF) protocol for computing binding free energies, we demonstrate the use of GPUGRID in the computation of accurate binding affinities of the Src SH2 domain/pYEEI ligand complex by reconstructing the PMF over 373 umbrella sampling windows of 55 ns each (20.5 mus of total data). We obtain a standard free energy of binding of -8.7 +/- 0.4 kcal/mol within 0.7 kcal/mol from experimental results. This infrastructure will provide the basis for a robust system for high-throughput accurate binding affinity prediction.
Meshfree methods for computational fluid dynamics
Directory of Open Access Journals (Sweden)
Jícha M.
2013-04-01
Full Text Available The paper deals with the convergence problem of the SPH (Smoothed Particle Hydrodynamics meshfree method for the solution of fluid dynamics tasks. In the introductory part, fundamental aspects of mesh- free methods, their definition, computational approaches and classification are discussed. In the following part, the methods of local integral representation, where SPH belongs are analyzed and specifically the method RKPM (Reproducing Kernel Particle Method is described. In the contribution, also the influence of boundary conditions on the SPH approximation consistence is analyzed, which has a direct impact on the convergence of the method. A classical boundary condition in the form of virtual particles does not ensure a sufficient order of consistence near the boundary of the definition domain of the task. This problem is solved by using ghost particles as a boundary condition, which was implemented into the SPH code as part of this work. Further, several numerical aspects linked with the SPH method are described. In the concluding part, results are presented of the application of the SPH method with ghost particles to the 2D shock tube example. Also results of tests of several parameters and modifications of the SPH code are shown.
Computational social dynamic modeling of group recruitment.
Energy Technology Data Exchange (ETDEWEB)
Berry, Nina M.; Lee, Marinna; Pickett, Marc; Turnley, Jessica Glicken (Sandia National Laboratories, Albuquerque, NM); Smrcka, Julianne D. (Sandia National Laboratories, Albuquerque, NM); Ko, Teresa H.; Moy, Timothy David (Sandia National Laboratories, Albuquerque, NM); Wu, Benjamin C.
2004-01-01
The Seldon software toolkit combines concepts from agent-based modeling and social science to create a computationally social dynamic model for group recruitment. The underlying recruitment model is based on a unique three-level hybrid agent-based architecture that contains simple agents (level one), abstract agents (level two), and cognitive agents (level three). This uniqueness of this architecture begins with abstract agents that permit the model to include social concepts (gang) or institutional concepts (school) into a typical software simulation environment. The future addition of cognitive agents to the recruitment model will provide a unique entity that does not exist in any agent-based modeling toolkits to date. We use social networks to provide an integrated mesh within and between the different levels. This Java based toolkit is used to analyze different social concepts based on initialization input from the user. The input alters a set of parameters used to influence the values associated with the simple agents, abstract agents, and the interactions (simple agent-simple agent or simple agent-abstract agent) between these entities. The results of phase-1 Seldon toolkit provide insight into how certain social concepts apply to different scenario development for inner city gang recruitment.
Spatiotemporal computed tomography of dynamic processes
Kaestner, Anders; Münch, Beat; Trtik, Pavel; Butler, Les
2011-12-01
Modern computed tomography (CT) equipment allowing fast 3-D imaging also makes it possible to monitor dynamic processes by 4-D imaging. Because the acquisition time of various 3-D-CT systems is still in the range of at least milliseconds or even hours, depending on the detector system and the source, the balance of the desired temporal and spatial resolution must be adjusted. Furthermore, motion artifacts will occur, especially at high spatial resolution and longer measuring times. We propose two approaches based on nonsequential projection angle sequences allowing a convenient postacquisition balance of temporal and spatial resolution. Both strategies are compatible with existing instruments, needing only a simple reprograming of the angle list used for projection acquisition and care with the projection order list. Both approaches will reduce the impact of artifacts due to motion. The strategies are applied and validated with cold neutron imaging of water desorption from originally saturated particles during natural air-drying experiments and with x-ray tomography of a polymer blend heated during imaging.
Graphical models for genetic analyses
DEFF Research Database (Denmark)
Lauritzen, Steffen Lilholt; Sheehan, Nuala A.
2003-01-01
This paper introduces graphical models as a natural environment in which to formulate and solve problems in genetics and related areas. Particular emphasis is given to the relationships among various local computation algorithms which have been developed within the hitherto mostly separate areas...... of graphical models and genetics. The potential of graphical models is explored and illustrated through a number of example applications where the genetic element is substantial or dominating....
Computational Fluid Dynamics Methods and Their Applications in Medical Science
Kowalewski Wojciech; Roszak Magdalena; Kołodziejczak Barbara; Ren-Kurc Anna; Bręborowicz Andrzej
2016-01-01
As defined by the National Institutes of Health: “Biomedical engineering integrates physical, chemical, mathematical, and computational sciences and engineering principles to study biology, medicine, behavior, and health”. Many issues in this area are closely related to fluid dynamics. This paper provides an overview of the basic concepts concerning Computational Fluid Dynamics and its applications in medicine.
Heckbert, Paul S
1994-01-01
Graphics Gems IV contains practical techniques for 2D and 3D modeling, animation, rendering, and image processing. The book presents articles on polygons and polyhedral; a mix of formulas, optimized algorithms, and tutorial information on the geometry of 2D, 3D, and n-D space; transformations; and parametric curves and surfaces. The text also includes articles on ray tracing; shading 3D models; and frame buffer techniques. Articles on image processing; algorithms for graphical layout; basic interpolation methods; and subroutine libraries for vector and matrix algebra are also demonstrated. Com
Directory of Open Access Journals (Sweden)
Brook Weld Muller
2014-12-01
Full Text Available This essay describes strategic approaches to graphic representation associated with critical environmental engagement and that build from the idea of works of architecture as stitches in the ecological fabric of the city. It focuses on the building up of partial or fragmented graphics in order to describe inclusive, open-ended possibilities for making architecture that marry rich experience and responsive performance. An aphoristic approach to crafting drawings involves complex layering, conscious absence and the embracing of tension. A self-critical attitude toward the generation of imagery characterized by the notion of ‘loose precision’ may lead to more transformative and environmentally responsive architectures.
Sugawara, Takuya; Ogihara, Yuki; Sakamoto, Yuji
2016-01-20
The point-based method and fast-Fourier-transform-based method are commonly used for calculation methods of computer-generation holograms. This paper proposes a novel fast calculation method for a patch model, which uses the point-based method. The method provides a calculation time that is proportional to the number of patches but not to that of the point light sources. This means that the method is suitable for calculating a wide area covered by patches quickly. Experiments using a graphics processing unit indicated that the proposed method is about 8 times or more faster than the ordinary point-based method.
Dynamics computation methodology applied to railcar vibrations
Vlaminck, R. R.
1974-01-01
The analytical models discussed present typical examples of analyses performed to optimize vehicle parameters and solve specific engineering problems. Subjects investigated include: (1) car body structural dynamics, (2) vehicle dynamic motions and loads, and (3) truck equalization.
Collaborative Computer Graphics Product Development between Academia and Government: A Dynamic Model
Fowler, Deborah R.; Kostis, Helen-Nicole
2016-01-01
Collaborations and partnerships between academia and government agencies are common, especially when it comes to research and development in the fields of science, engineering and technology. However, collaboration between a government agency and an art school is rather atypical. This paper presents the Collaborative Student Project, which aims to explore the following challenge: The ideation, development and realization of education and public outreach products for NASAs upcoming ICESat-2 mission in collaboration with art students.
Dynamic leaching test of personal computer components.
Li, Yadong; Richardson, Jay B; Niu, Xiaojun; Jackson, Ollie J; Laster, Jeremy D; Walker, Aaron K
2009-11-15
A dynamic leaching test (DLT) was developed and used to evaluate the leaching of toxic substances for electronic waste in the environment. The major components in personal computers (PCs) including motherboards, hard disc drives, floppy disc drives, and compact disc drives were tested. The tests lasted for 2 years for motherboards and 1.5 year for the disc drives. The extraction fluids for the standard toxicity characteristic leaching procedure (TCLP) and synthetic precipitation leaching procedure (SPLP) were used as the DLT leaching solutions. A total of 18 elements including Ag, Al, As, Au, Ba, Be, Cd, Cr, Cu, Fe, Ga, Ni, Pd, Pb, Sb, Se, Sn, and Zn were analyzed in the DLT leachates. Only Al, Cu, Fe, Ni, Pb, and Zn were commonly found in the DLT leachates of the PC components. Their leaching levels were much higher in TCLP extraction fluid than in SPLP extraction fluid. The toxic heavy metal Pb was found to continuously leach out of the components over the entire test periods. The cumulative amounts of Pb leached out of the motherboards in TCLP extraction fluid reached 2.0 g per motherboard over the 2-year test period, and that in SPLP extraction fluid were 75-90% less. The leaching rates or levels of Pb were largely affected by the content of galvanized steel in the PC components. The higher was the steel content, the lower the Pb leaching rate would be. The findings suggest that the obsolete PCs disposed of in landfills or discarded in the environment continuously release Pb for years when subjected to landfill leachate or rains.
Quantum Computation and Quantum Spin Dynamics
Raedt, Hans De; Michielsen, Kristel; Hams, Anthony; Miyashita, Seiji; Saito, Keiji
2001-01-01
We analyze the stability of quantum computations on physically realizable quantum computers by simulating quantum spin models representing quantum computer hardware. Examples of logically identical implementations of the controlled-NOT operation are used to demonstrate that the results of a quantum
Quantum Computation and Quantum Spin Dynamics
Raedt, Hans De; Michielsen, Kristel; Hams, Anthony; Miyashita, Seiji; Saito, Keiji
2001-01-01
We analyze the stability of quantum computations on physically realizable quantum computers by simulating quantum spin models representing quantum computer hardware. Examples of logically identical implementations of the controlled-NOT operation are used to demonstrate that the results of a quantum
Measuring Cognitive Load in Test Items: Static Graphics versus Animated Graphics
Dindar, M.; Kabakçi Yurdakul, I.; Inan Dönmez, F.
2015-01-01
The majority of multimedia learning studies focus on the use of graphics in learning process but very few of them examine the role of graphics in testing students' knowledge. This study investigates the use of static graphics versus animated graphics in a computer-based English achievement test from a cognitive load theory perspective. Three…
Graphics Display of Foreign Scripts.
Abercrombie, John R.
1987-01-01
Describes Graphics Project for Foreign Language Learning at the University of Pennsylvania, which has developed ways of displaying foreign scripts on microcomputers. Character design on computer screens is explained; software for graphics, printing, and language instruction is discussed; and a text editor is described that corrects optically…
Graphic filter library implemented in CUDA language
Peroutková, Hedvika
2009-01-01
This thesis deals with the problem of reducing computation time of raster image processing by parallel computing on graphics processing unit. Raster image processing thereby refers to the application of graphic filters, which can be applied in sequence with different settings. This thesis evaluates the suitability of using parallelization on graphic card for raster image adjustments based on multicriterial choice. Filters are implemented for graphics processing unit in CUDA language. Opacity ...
DEFF Research Database (Denmark)
Bergstrøm-Nielsen, Carl
2010-01-01
Graphic notation is taught to music therapy students at Aalborg University in both simple and elaborate forms. This is a method of depicting music visually, and notations may serve as memory aids, as aids for analysis and reflection, and for communication purposes such as supervision or within...
Personal computer aided cerebral perfusion imaging with dynamic CT
Institute of Scientific and Technical Information of China (English)
林燕; 高培毅
2004-01-01
@@Reports on the clinical implementation of dynamic computerised tomography (CT) perfusion imaging and quantitative measurement have increased dramatically of late.1-8 The advantages of dynamic CT perfusion imaging and quantitative measurement for the diagnosis of acute cerebral infarction have been acknowledged. However, most overseas CT vendors set perfusion imaging software package as an option for graphic workstation at a too high price for domestic practitioners. To foster the domestic implementation and development of this new technology, we have extended the earlier work.1,2 Applying the theory of central volume principle to DICOM 3.0 standard forms of prime CT images, we developed dynamic CT perfusion imaging and quantitative measure-ment programmes for PCs using Visual C+ + in Windows 98 system.
Ochiai, Yoichi; Hoshi, Takayuki; Rekimoto, Jun; Hasegawa, Satoshi; Hayasaki, Yoshio
2015-01-01
We present a method of rendering aerial and volumetric graphics using femtosecond lasers. A high-intensity laser excites a physical matter to emit light at an arbitrary 3D position. Popular applications can then be explored especially since plasma induced by a femtosecond laser is safer than that generated by a nanosecond laser. There are two methods of rendering graphics with a femtosecond laser in air: Producing holograms using spatial light modulation technology, and scanning of a laser beam by a galvano mirror. The holograms and workspace of the system proposed here occupy a volume of up to 1 cm^3; however, this size is scalable depending on the optical devices and their setup. This paper provides details of the principles, system setup, and experimental evaluation, and discussions on scalability, design space, and applications of this system. We tested two laser sources: an adjustable (30-100 fs) laser which projects up to 1,000 pulses per second at energy up to 7 mJ per pulse, and a 269-fs laser which p...
Computing Bisectors in a Dynamic Geometry Environment
Botana, Francisco
2013-01-01
In this note, an approach combining dynamic geometry and automated deduction techniques is used to study the bisectors between points and curves. Usual teacher constructions for bisectors are discussed, showing that inherent limitations in dynamic geometry software impede their thorough study. We show that the interactive sketching of bisectors…
Spatial Dynamic Structures and Mobility in Computation
Aman, Bogdan
2011-01-01
Membrane computing is a well-established and successful research field which belongs to the more general area of molecular computing. Membrane computing aims at defining parallel and non-deterministic computing models, called membrane systems or P Systems, which abstract from the functioning and structure of the cell. A membrane system consists of a spatial structure, a hierarchy of membranes which do not intersect, with a distinguishable membrane called skin surrounding all of them. A membrane without any other membranes inside is elementary, while a non-elementary membrane is a composite membrane. The membranes define demarcations between regions; for each membrane there is a unique associated region. Since we have a one-to-one correspondence, we sometimes use membrane instead of region, and vice-versa. The space outside the skin membrane is called the environment. In this thesis we define and investigate variants of systems of mobile membranes as models for molecular computing and as modelling paradigms fo...
Directory of Open Access Journals (Sweden)
Prof. Patty K. Wongpakdee
2013-06-01
Full Text Available “Resurfacing Graphics” deals with the subject of unconventional design, with the purpose of engaging the viewer to experience the graphics beyond paper’s passive surface. Unconventional designs serve to reinvigorate people, whose senses are dulled by the typical, printed graphics, which bombard them each day. Today’s cutting-edge designers, illustrators and artists utilize graphics in a unique manner that allows for tactile interaction. Such works serve as valuable teaching models and encourage students to do the following: 1 investigate the trans-disciplines of art and technology; 2 appreciate that this approach can have a positive effect on the environment; 3 examine and research other approaches of design communications and 4 utilize new mediums to stretch the boundaries of artistic endeavor. This paper examines how visuals communicators are “Resurfacing Graphics” by using atypical surfaces and materials such as textile, wood, ceramics and even water. Such non-traditional transmissions of visual language serve to demonstrate student’s overreliance on paper as an outdated medium. With this exposure, students can become forward-thinking, eco-friendly, creative leaders by expanding their creative breadth and continuing the perpetual exploration for new ways to make their mark.
Directory of Open Access Journals (Sweden)
Prof. Patty K. Wongpakdee
2013-06-01
Full Text Available “Resurfacing Graphics” deals with the subject of unconventional design, with the purpose of engaging the viewer to experience the graphics beyond paper’s passive surface. Unconventional designs serve to reinvigorate people, whose senses are dulled by the typical, printed graphics, which bombard them each day. Today’s cutting-edge designers, illustrators and artists utilize graphics in a unique manner that allows for tactile interaction. Such works serve as valuable teaching models and encourage students to do the following: 1 investigate the trans-disciplines of art and technology; 2 appreciate that this approach can have a positive effect on the environment; 3 examine and research other approaches of design communications and 4 utilize new mediums to stretch the boundaries of artistic endeavor. This paper examines how visuals communicators are “Resurfacing Graphics” by using atypical surfaces and materials such as textile, wood, ceramics and even water. Such non-traditional transmissions of visual language serve to demonstrate student’s overreliance on paper as an outdated medium. With this exposure, students can become forward-thinking, eco-friendly, creative leaders by expanding their creative breadth and continuing the perpetual exploration for new ways to make their mark.
Type II Quantum Computing Algorithm For Computational Fluid Dynamics
2006-03-01
Hall/CRC (2003) 30. Gilbert Strang, Linear Algebra and its Applications. Thompson Learning, Inc (1988) 31. George Arfken and Hans Weber, Mathematical ... method is called ensemble Figure 3. Ensemble measurement averages the measurement results of N identical quantum computers to obtain the magnitude of...the lattice Boltzmann equation. There are two methods of modeling this mesoscopic equation. The first approach is to directly simulate the
Andrade, Xavier
2013-01-01
We discuss the application of graphical processing units (GPUs) to accelerate real-space density functional theory (DFT) calculations. To make our implementation efficient, we have developed a scheme to expose the data parallelism available in the DFT approach; this is applied to the different procedures required for a real-space DFT calculation. We present results for current-generation GPUs from AMD and Nvidia, which show that our scheme, implemented in the free code OCTOPUS, can reach a sustained performance of up to 90 GFlops for a single GPU, representing an important speed-up when compared to the CPU version of the code. Moreover, for some systems our implementation can outperform a GPU Gaussian basis set code, showing that the real-space approach is a competitive alternative for DFT simulations on GPUs.
Andrade, Xavier; Aspuru-Guzik, Alán
2013-10-01
We discuss the application of graphical processing units (GPUs) to accelerate real-space density functional theory (DFT) calculations. To make our implementation efficient, we have developed a scheme to expose the data parallelism available in the DFT approach; this is applied to the different procedures required for a real-space DFT calculation. We present results for current-generation GPUs from AMD and Nvidia, which show that our scheme, implemented in the free code Octopus, can reach a sustained performance of up to 90 GFlops for a single GPU, representing a significant speed-up when compared to the CPU version of the code. Moreover, for some systems, our implementation can outperform a GPU Gaussian basis set code, showing that the real-space approach is a competitive alternative for DFT simulations on GPUs.
Hu, Hongda; Shu, Hong; Hu, Zhiyong; Xu, Jianhui
2016-04-01
Kriging interpolation provides the best linear unbiased estimation for unobserved locations, but its heavy computation limits the manageable problem size in practice. To address this issue, an efficient interpolation procedure incorporating the fast Fourier transform (FFT) was developed. Extending this efficient approach, we propose an FFT-based parallel algorithm to accelerate regression Kriging interpolation on an NVIDIA® compute unified device architecture (CUDA)-enabled graphic processing unit (GPU). A high-performance cuFFT library in the CUDA toolkit was introduced to execute computation-intensive FFTs on the GPU, and three time-consuming processes were redesigned as kernel functions and executed on the CUDA cores. A MODIS land surface temperature 8-day image tile at a resolution of 1 km was resampled to create experimental datasets at eight different output resolutions. These datasets were used as the interpolation grids with different sizes in a comparative experiment. Experimental results show that speedup of the FFT-based regression Kriging interpolation accelerated by GPU can exceed 1000 when processing datasets with large grid sizes, as compared to the traditional Kriging interpolation running on the CPU. These results demonstrate that the combination of FFT methods and GPU-based parallel computing techniques greatly improves the computational performance without loss of precision.
Automated Computational Fluid Dynamics Design With Shape Optimization Project
National Aeronautics and Space Administration — Computational fluid dynamics (CFD) is used as an analysis tool to help the designer gain greater understanding of the fluid flow phenomena involved in the...
Automated Computational Fluid Dynamics Design With Shape Optimization Project
National Aeronautics and Space Administration — Computational fluid dynamics (CFD) is used as an analysis tool to help the designer gain greater understanding of the fluid flow phenomena involved in the components...
Knibbe, H.; Vuik, C.; Oosterlee, C.W.
2015-01-01
In geophysical applications, the interest in least-squares migration (LSM) as an imaging algorithm is increasing due to the demand for more accurate solutions and the development of high-performance computing. The computational engine of LSM in this work is the numerical solution of the 3D Helmholtz
Graphic Novels in Your School Library
Karp, Jesse
2011-01-01
Many educators now agree that graphic novels inform as well as entertain, and to dismiss the educational potential of the graphic novel is to throw away a golden opportunity to reach out to young readers. This dynamic book takes a look at the term "graphic novel," how the format has become entwined in our culture, and the ways in which graphic…
Graphic Novels in Your School Library
Karp, Jesse
2011-01-01
Many educators now agree that graphic novels inform as well as entertain, and to dismiss the educational potential of the graphic novel is to throw away a golden opportunity to reach out to young readers. This dynamic book takes a look at the term "graphic novel," how the format has become entwined in our culture, and the ways in which graphic…
The Computer Simulation of Liquids by Molecular Dynamics.
Smith, W.
1987-01-01
Proposes a mathematical computer model for the behavior of liquids using the classical dynamic principles of Sir Isaac Newton and the molecular dynamics method invented by other scientists. Concludes that other applications will be successful using supercomputers to go beyond simple Newtonian physics. (CW)
Prospects for Computational Fluid Dynamics in Room Air Contaminant Control
DEFF Research Database (Denmark)
Nielsen, Peter V.
The fluid dynamics research is strongly influenced by the increasing computer power which has been available for the last decades. This development is obvious from the curve in figure 1 which shows the computation cost as a function of years. It is obvious that the cost for a given job...
Unsteady computational fluid dynamics in aeronautics
Tucker, P G
2014-01-01
The field of Large Eddy Simulation (LES) and hybrids is a vibrant research area. This book runs through all the potential unsteady modelling fidelity ranges, from low-order to LES. The latter is probably the highest fidelity for practical aerospace systems modelling. Cutting edge new frontiers are defined. One example of a pressing environmental concern is noise. For the accurate prediction of this, unsteady modelling is needed. Hence computational aeroacoustics is explored. It is also emerging that there is a critical need for coupled simulations. Hence, this area is also considered and the tensions of utilizing such simulations with the already expensive LES. This work has relevance to the general field of CFD and LES and to a wide variety of non-aerospace aerodynamic systems (e.g. cars, submarines, ships, electronics, buildings). Topics treated include unsteady flow techniques; LES and hybrids; general numerical methods; computational aeroacoustics; computational aeroelasticity; coupled simulations and...
Computational fluid dynamics for sport simulation
2009-01-01
All over the world sport plays a prominent role in society: as a leisure activity for many, as an ingredient of culture, as a business and as a matter of national prestige in such major events as the World Cup in soccer or the Olympic Games. Hence, it is not surprising that science has entered the realm of sports, and, in particular, that computer simulation has become highly relevant in recent years. This is explored in this book by choosing five different sports as examples, demonstrating that computational science and engineering (CSE) can make essential contributions to research on sports topics on both the fundamental level and, eventually, by supporting athletes’ performance.
Directory of Open Access Journals (Sweden)
Kui Liu
2017-02-01
Full Text Available This paper presents the first attempt at combining Cloud with Graphic Processing Units (GPUs in a complementary manner within the framework of a real-time high performance computation architecture for the application of detecting and tracking multiple moving targets based on Wide Area Motion Imagery (WAMI. More specifically, the GPU and Cloud Moving Target Tracking (GC-MTT system applied a front-end web based server to perform the interaction with Hadoop and highly parallelized computation functions based on the Compute Unified Device Architecture (CUDA©. The introduced multiple moving target detection and tracking method can be extended to other applications such as pedestrian tracking, group tracking, and Patterns of Life (PoL analysis. The cloud and GPUs based computing provides an efficient real-time target recognition and tracking approach as compared to methods when the work flow is applied using only central processing units (CPUs. The simultaneous tracking and recognition results demonstrate that a GC-MTT based approach provides drastically improved tracking with low frame rates over realistic conditions.
Liu, Kui; Wei, Sixiao; Chen, Zhijiang; Jia, Bin; Chen, Genshe; Ling, Haibin; Sheaff, Carolyn; Blasch, Erik
2017-02-12
This paper presents the first attempt at combining Cloud with Graphic Processing Units (GPUs) in a complementary manner within the framework of a real-time high performance computation architecture for the application of detecting and tracking multiple moving targets based on Wide Area Motion Imagery (WAMI). More specifically, the GPU and Cloud Moving Target Tracking (GC-MTT) system applied a front-end web based server to perform the interaction with Hadoop and highly parallelized computation functions based on the Compute Unified Device Architecture (CUDA©). The introduced multiple moving target detection and tracking method can be extended to other applications such as pedestrian tracking, group tracking, and Patterns of Life (PoL) analysis. The cloud and GPUs based computing provides an efficient real-time target recognition and tracking approach as compared to methods when the work flow is applied using only central processing units (CPUs). The simultaneous tracking and recognition results demonstrate that a GC-MTT based approach provides drastically improved tracking with low frame rates over realistic conditions.
Liu, Kui; Wei, Sixiao; Chen, Zhijiang; Jia, Bin; Chen, Genshe; Ling, Haibin; Sheaff, Carolyn; Blasch, Erik
2017-01-01
This paper presents the first attempt at combining Cloud with Graphic Processing Units (GPUs) in a complementary manner within the framework of a real-time high performance computation architecture for the application of detecting and tracking multiple moving targets based on Wide Area Motion Imagery (WAMI). More specifically, the GPU and Cloud Moving Target Tracking (GC-MTT) system applied a front-end web based server to perform the interaction with Hadoop and highly parallelized computation functions based on the Compute Unified Device Architecture (CUDA©). The introduced multiple moving target detection and tracking method can be extended to other applications such as pedestrian tracking, group tracking, and Patterns of Life (PoL) analysis. The cloud and GPUs based computing provides an efficient real-time target recognition and tracking approach as compared to methods when the work flow is applied using only central processing units (CPUs). The simultaneous tracking and recognition results demonstrate that a GC-MTT based approach provides drastically improved tracking with low frame rates over realistic conditions. PMID:28208684
Spatiotemporal Dynamics and Reliable Computations in Recurrent Spiking Neural Networks
Pyle, Ryan; Rosenbaum, Robert
2017-01-01
Randomly connected networks of excitatory and inhibitory spiking neurons provide a parsimonious model of neural variability, but are notoriously unreliable for performing computations. We show that this difficulty is overcome by incorporating the well-documented dependence of connection probability on distance. Spatially extended spiking networks exhibit symmetry-breaking bifurcations and generate spatiotemporal patterns that can be trained to perform dynamical computations under a reservoir computing framework.
Dynamic traffic assignment on parallel computers
Energy Technology Data Exchange (ETDEWEB)
Nagel, K.; Frye, R.; Jakob, R.; Rickert, M.; Stretz, P.
1998-12-01
The authors describe part of the current framework of the TRANSIMS traffic research project at the Los Alamos National Laboratory. It includes parallel implementations of a route planner and a microscopic traffic simulation model. They present performance figures and results of an offline load-balancing scheme used in one of the iterative re-planning runs required for dynamic route assignment.
Dynamic grid adaptation for computational magnetohydrodynamics
Keppens, R.; Nool, M.; Zegeling, P. A.; Goedbloed, J. P.; Bubak, M.; Williams, R.; Afsarmanesh, H.; Hertzberger, B.
2000-01-01
In many plasma physical and astrophysical problems, both linear and nonlinear effects can lead to global dynamics that induce, or occur simultaneously with, local phenomena. For example, a magnetically confined plasma column can potentially posses global magnetohydrodynamic (MHD) eigenmodes with an
Computing in Large-Scale Dynamic Systems
Pruteanu, A.S.
2013-01-01
Software applications developed for large-scale systems have always been difficult to de- velop due to problems caused by the large number of computing devices involved. Above a certain network size (roughly one hundred), necessary services such as code updating, topol- ogy discovery and data dissem
Computer and graphics modeling of heat transfer and phase change in a wall with randomly imbibed PCM
Energy Technology Data Exchange (ETDEWEB)
Solomon, A.D.
1989-03-01
We describe the theoretical basis and computer implementation of a simulation code for heat transfer and phase change in a rectangular 2-dimensional region in which PCM has been randomly placed with a preassigned volume fraction.
Triangular Dynamic Architecture for Distributed Computing in a LAN Environment
Hossain, M Shahriar; Fuad, M Muztaba; Deb, Debzani
2011-01-01
A computationally intensive large job, granulized to concurrent pieces and operating in a dynamic environment should reduce the total processing time. However, distributing jobs across a networked environment is a tedious and difficult task. Job distribution in a Local Area Network based on Triangular Dynamic Architecture (TDA) is a mechanism that establishes a dynamic environment for job distribution, load balancing and distributed processing with minimum interaction from the user. This paper introduces TDA and discusses its architecture and shows the benefits gained by utilizing such architecture in a distributed computing environment.
Quantum Computing, $NP$-complete Problems and Chaotic Dynamics
Ohya, M; Ohya, Masanori; Volovich, Igor V.
1999-01-01
An approach to the solution of NP-complete problems based on quantumcomputing and chaotic dynamics is proposed. We consider the satisfiabilityproblem and argue that the problem, in principle, can be solved in polynomialtime if we combine the quantum computer with the chaotic dynamics amplifierbased on the logistic map. We discuss a possible implementation of such achaotic quantum computation by using the atomic quantum computer with quantumgates described by the Hartree-Fock equations. In this case, in principle, onecan build not only standard linear quantum gates but also nonlinear gates andmoreover they obey to Fermi statistics. This new type of entaglement relatedwith Fermi statistics can be interesting also for quantum communication theory.
THE USING OF GRAPHICAL EDITOR IN THE ENGINEERING GRAPHICS AND THE COURSE DESIGNING
Directory of Open Access Journals (Sweden)
KARPYUK L. V.
2016-08-01
Full Text Available The problems of learning students of the engineering and computer graphics of the course on the base of computer-aided design (CAD were described in the article. The examples of training tasks for acquiring knowledge of work in the environment of graphical editor of AutoCAD were shown. These examples are needed to perform drawings on The Engineering Graphics, and also for a graphic part of Course Projects for students of mechanical specialties.
Computational Methods for Dynamic Stability and Control Derivatives
Green, Lawrence L.; Spence, Angela M.; Murphy, Patrick C.
2004-01-01
Force and moment measurements from an F-16XL during forced pitch oscillation tests result in dynamic stability derivatives, which are measured in combinations. Initial computational simulations of the motions and combined derivatives are attempted via a low-order, time-dependent panel method computational fluid dynamics code. The code dynamics are shown to be highly questionable for this application and the chosen configuration. However, three methods to computationally separate such combined dynamic stability derivatives are proposed. One of the separation techniques is demonstrated on the measured forced pitch oscillation data. Extensions of the separation techniques to yawing and rolling motions are discussed. In addition, the possibility of considering the angles of attack and sideslip state vector elements as distributed quantities, rather than point quantities, is introduced.
Directory of Open Access Journals (Sweden)
Tae-Hwan Joung
2012-03-01
Full Text Available Autonomous Underwater Vehicles (AUVs provide a useful means of collecting detailed oceano-graphic information. The hull resistance of an AUV is an important factor in determining the power requirements and range of the vehicle. This paper describes a procedure using Computational Fluid Dynamics (CFD for determining the hull resistance of an AUV under development, for a given propeller rotation speed and within a given range of AUV velocities. The CFD analysis results reveal the distribution of the hydrodynamic values (velocity, pressure, etc. around the AUV hull and its ducted propeller. The paper then proceeds to present a methodology for optimizing the AUV profile in order to reduce the total resistance. This paper demonstrates that shape optimization of conceptual designs is possible using the commercial CFD package contained in Ansys™. The optimum design to minimize the drag force of the AUV was identified for a given object function and a set of constrained design parameters.
Directory of Open Access Journals (Sweden)
Francisco José Borge Cordovilla
2013-11-01
Full Text Available The application of the procedures commonly used by computer graphics has allowed the author contextualize the existing remains under the present church of San Pelayo de Oviedo as corresponding to a high medieval crypt, built by the shop that built Santa Maria del Rey Casto basilica and Foncalada fountain, reigning Alfonso II (to 842, including making a joint hypothesis of the same with the primitive basilica of San Juan Bautista named by early medieval sources in Asturias, characterized by a complex liturgical equipment, "confessio" semi-underground low chancel and sanctuary high; by linking the building with other Europeans, the Merovingian and Anglo-Saxon area, of which derived type, also present in the s Roman basilicas of the eighth century.
A new computational structure for real-time dynamics
Energy Technology Data Exchange (ETDEWEB)
Izaguirre, A. (New Jersey Inst. of Tech., Newark (United States)); Hashimoto, Minoru (Univ. of Electrocommunications, Tokyo (Japan))
1992-08-01
The authors present an efficient structure for the computation of robot dynamics in real time. The fundamental characteristic of this structure is the division of the computation into a high-priority synchronous task and low-priority background tasks, possibly sharing the resources of a conventional computing unit based on commercial microprocessors. The background tasks compute the inertial and gravitational coefficients as well as the forces due to the velocities of the joints. In each control sample period, the high-priority synchronous task computes the product of the inertial coefficients by the accelerations of the joints and performs the summation of the torques due to the velocities and gravitational forces. Kircanski et al. (1986) have shown that the bandwidth of the variation of joint angles and of their velocities is an order of magnitude less than the variation of joint accelerations. This result agrees with the experiments the authors have carried out using a PUMA 260 robot. Two main strategies contribute to reduce the computational burden associated with the evaluation of the dynamic equations. The first involves the use of efficient algorithms for the evaluation of the equations. The second is aimed at reducing the number of dynamic parameters by identifying beforehand the linear dependencies among these parameters, as well as carrying out a significance analysis of the parameters' contribution to the final joint torques. The actual code used to evaluate this dynamic model is entirely computer generated from experimental data, requiring no other manual intervention than performing a campaign of measurements.
Computer simulation of confined liquid crystal dynamics
Webster, R E
2001-01-01
are performed of the formation of structures in confined smectic systems where layer tilt is induced by an imposed surface pretilt. Results show that bookshelf, chevron and tilled layer structures are observable in a confined Gay-Berne system. The formation and stability of the chevron structure are shown to be influenced by surface slip. Results are presented from a series of simulations undertaken to determine whether dynamic processes observed in device-scale liquid crystal cells confined between aligning substrates can be simulated in a molecular system using parallel molecular dynamics of the Gay-Berne model. In a nematic cell, on removal of an aligning field, initial near-surface director relaxation can induce flow, termed 'backflow' in the liquid. This, in turn, can cause director rotation, termed 'orientational kickback', in the centre of the cell. Simulations are performed of the relaxation in nematic systems confined between substrates with a common alignment on removal of an aligning field. Results...
Osmosis : a molecular dynamics computer simulation study
Lion, Thomas
Osmosis is a phenomenon of critical importance in a variety of processes ranging from the transport of ions across cell membranes and the regulation of blood salt levels by the kidneys to the desalination of water and the production of clean energy using potential osmotic power plants. However, despite its importance and over one hundred years of study, there is an ongoing confusion concerning the nature of the microscopic dynamics of the solvent particles in their transfer across the membrane. In this thesis the microscopic dynamical processes underlying osmotic pressure and concentration gradients are investigated using molecular dynamics (MD) simulations. I first present a new derivation for the local pressure that can be used for determining osmotic pressure gradients. Using this result, the steady-state osmotic pressure is studied in a minimal model for an osmotic system and the steady-state density gradients are explained using a simple mechanistic hopping model for the solvent particles. The simulation setup is then modified, allowing us to explore the timescales involved in the relaxation dynamics of the system in the period preceding the steady state. Further consideration is also given to the relative roles of diffusive and non-diffusive solvent transport in this period. Finally, in a novel modification to the classic osmosis experiment, the solute particles are driven out-of-equilibrium by the input of energy. The effect of this modification on the osmotic pressure and the osmotic ow is studied and we find that active solute particles can cause reverse osmosis to occur. The possibility of defining a new "osmotic effective temperature" is also considered and compared to the results of diffusive and kinetic temperatures..
DYNAMIC TASK PARTITIONING MODEL IN PARALLEL COMPUTING
Directory of Open Access Journals (Sweden)
Javed Ali
2012-04-01
Full Text Available Parallel computing systems compose task partitioning strategies in a true multiprocessing manner. Such systems share the algorithm and processing unit as computing resources which leads to highly inter process communications capabilities. The main part of the proposed algorithm is resource management unit which performs task partitioning and co-scheduling .In this paper, we present a technique for integrated task partitioning and co-scheduling on the privately owned network. We focus on real-time and non preemptive systems. A large variety of experiments have been conducted on the proposed algorithm using synthetic and real tasks. Goal of computation model is to provide a realistic representation of the costs of programming The results show the benefit of the task partitioning. The main characteristics of our method are optimal scheduling and strong link between partitioning, scheduling and communication. Some important models for task partitioning are also discussed in the paper. We target the algorithm for task partitioning which improve the inter process communication between the tasks and use the recourses of the system in the efficient manner. The proposed algorithm contributes the inter-process communication cost minimization amongst the executing processes.
Low Power Dynamic Scheduling for Computing Systems
Neely, Michael J
2011-01-01
This paper considers energy-aware control for a computing system with two states: "active" and "idle." In the active state, the controller chooses to perform a single task using one of multiple task processing modes. The controller then saves energy by choosing an amount of time for the system to be idle. These decisions affect processing time, energy expenditure, and an abstract attribute vector that can be used to model other criteria of interest (such as processing quality or distortion). The goal is to optimize time average system performance. Applications of this model include a smart phone that makes energy-efficient computation and transmission decisions, a computer that processes tasks subject to rate, quality, and power constraints, and a smart grid energy manager that allocates resources in reaction to a time varying energy price. The solution methodology of this paper uses the theory of optimization for renewal systems developed in our previous work. This paper is written in tutorial form and devel...
Graphical Models for Optimal Power Flow
Dvijotham, Krishnamurthy; Chertkov, Michael; Misra, Sidhant; Vuffray, Marc
2016-01-01
Optimal power flow (OPF) is the central optimization problem in electric power grids. Although solved routinely in the course of power grid operations, it is known to be strongly NP-hard in general, and weakly NP-hard over tree networks. In this paper, we formulate the optimal power flow problem over tree networks as an inference problem over a tree-structured graphical model where the nodal variables are low-dimensional vectors. We adapt the standard dynamic programming algorithm for inference over a tree-structured graphical model to the OPF problem. Combining this with an interval discretization of the nodal variables, we develop an approximation algorithm for the OPF problem. Further, we use techniques from constraint programming (CP) to perform interval computations and adaptive bound propagation to obtain practically efficient algorithms. Compared to previous algorithms that solve OPF with optimality guarantees using convex relaxations, our approach is able to work for arbitrary distribution networks an...
Statistical graphics: mapping the pathways of science.
Wainer, H; Velleman, P F
2001-01-01
This chapter traces the evolution of statistical graphics starting with its departure from the common noun structure of Cartesian determinism, through William Playfair's revolutionary grammatical shift to graphs as proper nouns, and alights on the modern conception of graph as an active participant in the scientific process of discovery. The ubiquitous availability of data, software, and cheap, high-powered, computing when coupled with the broad acceptance of the ideas in Tukey's 1977 treatise on exploratory data analysis has yielded a fundamental change in the way that the role of statistical graphics is thought of within science-as a dynamic partner and guide to the future rather than as a static monument to the discoveries of the past. We commemorate and illustrate this development while pointing readers to the new tools available and providing some indications of their potential.
Raster graphics display library
Grimsrud, Anders; Stephenson, Michael B.
1987-01-01
The Raster Graphics Display Library (RGDL) is a high level subroutine package that give the advanced raster graphics display capabilities needed. The RGDL uses FORTRAN source code routines to build subroutines modular enough to use as stand-alone routines in a black box type of environment. Six examples are presented which will teach the use of RGDL in the fastest, most complete way possible. Routines within the display library that are used to produce raster graphics are presented in alphabetical order, each on a separate page. Each user-callable routine is described by function and calling parameters. All common blocks that are used in the display library are listed and the use of each variable within each common block is discussed. A reference on the include files that are necessary to compile the display library is contained. Each include file and its purpose are listed. The link map for MOVIE.BYU version 6, a general purpose computer graphics display system that uses RGDL software, is also contained.
Exponential rise of dynamical complexity in quantum computing through projections.
Burgarth, Daniel Klaus; Facchi, Paolo; Giovannetti, Vittorio; Nakazato, Hiromichi; Pascazio, Saverio; Yuasa, Kazuya
2014-10-10
The ability of quantum systems to host exponentially complex dynamics has the potential to revolutionize science and technology. Therefore, much effort has been devoted to developing of protocols for computation, communication and metrology, which exploit this scaling, despite formidable technical difficulties. Here we show that the mere frequent observation of a small part of a quantum system can turn its dynamics from a very simple one into an exponentially complex one, capable of universal quantum computation. After discussing examples, we go on to show that this effect is generally to be expected: almost any quantum dynamics becomes universal once 'observed' as outlined above. Conversely, we show that any complex quantum dynamics can be 'purified' into a simpler one in larger dimensions. We conclude by demonstrating that even local noise can lead to an exponentially complex dynamics.
Photonic Nonlinear Transient Computing with Multiple-Delay Wavelength Dynamics
Martinenghi, Romain; Rybalko, Sergei; Jacquot, Maxime; Chembo, Yanne K.; Larger, Laurent
2012-06-01
We report on the experimental demonstration of a hybrid optoelectronic neuromorphic computer based on a complex nonlinear wavelength dynamics including multiple delayed feedbacks with randomly defined weights. This neuromorphic approach is based on a new paradigm of a brain-inspired computational unit, intrinsically differing from Turing machines. This recent paradigm consists in expanding the input information to be processed into a higher dimensional phase space, through the nonlinear transient response of a complex dynamics excited by the input information. The computed output is then extracted via a linear separation of the transient trajectory in the complex phase space. The hyperplane separation is derived from a learning phase consisting of the resolution of a regression problem. The processing capability originates from the nonlinear transient, resulting in nonlinear transient computing. The computational performance is successfully evaluated on a standard benchmark test, namely, a spoken digit recognition task.
图形处理器在通用计算中的应用%Application of graphics processing unit in general purpose computation
Institute of Scientific and Technical Information of China (English)
张健; 陈瑞
2009-01-01
基于图形处理器(GPU)的计算统一设备体系结构(compute unified device architecture,CUDA)构架,阐述了GPU用于通用计算的原理和方法.在Geforce8800GT下,完成了矩阵乘法运算实验.实验结果表明,随着矩阵阶数的递增,无论是GPU还是CPU处理,速度都在减慢.数据增加100倍后,GPU上的运算时间仅增加了3.95倍,而CPU的运算时间增加了216.66倍.%Based on the CUDA (compute unified device architecture) of GPU (graphics processing unit), the technical fundamentals and methods for general purpose computation on GPU are introduced. The algorithm of matrix multiplication is simulated on Geforce8800 GT. With the increasing of matrix order, algorithm speed is slowed either on CPU or on GPU. After the data quantity increases to 100 times, the operation time only increased in 3.95 times on GPU, and 216.66 times on CPU.
Finite Element Computational Dynamics of Rotating Systems
Directory of Open Access Journals (Sweden)
Jaroslav Mackerle
1999-01-01
Full Text Available This bibliography lists references to papers, conference proceedings and theses/dissertations dealing with finite element analysis of rotor dynamics problems that were published in 1994–1998. It contains 319 citations. Also included, as separate subsections, are finite element analyses of rotor elements – discs, shafts, spindles, and blades. Topics dealing with fracture mechanics, contact and stability problems of rotating machinery are also considered in specific sections. The last part of the bibliography presents papers dealing with specific industrial applications.
Perspective: Computer simulations of long time dynamics
Energy Technology Data Exchange (ETDEWEB)
Elber, Ron [Department of Chemistry, The Institute for Computational Engineering and Sciences, University of Texas at Austin, Austin, Texas 78712 (United States)
2016-02-14
Atomically detailed computer simulations of complex molecular events attracted the imagination of many researchers in the field as providing comprehensive information on chemical, biological, and physical processes. However, one of the greatest limitations of these simulations is of time scales. The physical time scales accessible to straightforward simulations are too short to address many interesting and important molecular events. In the last decade significant advances were made in different directions (theory, software, and hardware) that significantly expand the capabilities and accuracies of these techniques. This perspective describes and critically examines some of these advances.
Directory of Open Access Journals (Sweden)
Konrad Gauda
2014-11-01
Full Text Available The article presents the possibility of using a computer with specialized software to support education of students with communication disorders. It also presents the results of preliminary tests based on the original program developed for students with intellectual disabilities in moderate and significant degree of disability in the field of alternative communication with using pictograms and pcs.
DiSalvo, Betsy
2014-01-01
To determine appropriate computer science curricula, educators sought to better understand the different affordances of teaching with a visual programming language (Alice) or a text-based language (Jython). Although students often preferred one language, that language wasn't necessarily the one from which they learned the most.
Unzueta, Caridad H.
2009-01-01
Many culturally and linguistically diverse (CLD) students with specific learning disabilities (SLD) struggle with the writing process. Particularly, they have difficulties developing and expanding ideas, organizing and elaborating sentences, and revising and editing their compositions (Graham, Harris, & Larsen, 2001; Myles, 2002). Computer graphic…
Institute of Scientific and Technical Information of China (English)
刘圣军; 韩旭里
2011-01-01
In this paper, it analyses that the existing problems in the teaching and learning of the computer graphics course. According to the major characteristics of information and computing science, the course characteristics of computer graphics, and the bases of students, some reforms are represented which include reoganizing the Course con- tents, adapting the hybrid method of ease teaching and visualization teaching, and designing testable and combining practice programs.%本文分析了当前《计算机图形学》课程的教学现状。并基于信息与计算科学专业特点、《计算机图形学》课程特点及学生的基础，从重组教学内容、采用案例教学与可视教学相结合的方法、设计验证性和综合性相结合的实践项目三个方面进行了一些教学改革探索。
Markov chain Monte Carlo methods in directed graphical models
DEFF Research Database (Denmark)
Højbjerre, Malene
Directed graphical models present data possessing a complex dependence structure, and MCMC methods are computer-intensive simulation techniques to approximate high-dimensional intractable integrals, which emerge in such models with incomplete data. MCMC computations in directed graphical models...
SD-CAS: Spin Dynamics by Computer Algebra System.
Filip, Xenia; Filip, Claudiu
2010-11-01
A computer algebra tool for describing the Liouville-space quantum evolution of nuclear 1/2-spins is introduced and implemented within a computational framework named Spin Dynamics by Computer Algebra System (SD-CAS). A distinctive feature compared with numerical and previous computer algebra approaches to solving spin dynamics problems results from the fact that no matrix representation for spin operators is used in SD-CAS, which determines a full symbolic character to the performed computations. Spin correlations are stored in SD-CAS as four-entry nested lists of which size increases linearly with the number of spins into the system and are easily mapped into analytical expressions in terms of spin operator products. For the so defined SD-CAS spin correlations a set of specialized functions and procedures is introduced that are essential for implementing basic spin algebra operations, such as the spin operator products, commutators, and scalar products. They provide results in an abstract algebraic form: specific procedures to quantitatively evaluate such symbolic expressions with respect to the involved spin interaction parameters and experimental conditions are also discussed. Although the main focus in the present work is on laying the foundation for spin dynamics symbolic computation in NMR based on a non-matrix formalism, practical aspects are also considered throughout the theoretical development process. In particular, specific SD-CAS routines have been implemented using the YACAS computer algebra package (http://yacas.sourceforge.net), and their functionality was demonstrated on a few illustrative examples.
A modular system for computational fluid dynamics
McCarthy, D. R.; Foutch, D. W.; Shurtleff, G. E.
This paper describes the Modular System for Compuational Fluid Dynamics (MOSYS), a software facility for the construction and execution of arbitrary solution procedures on multizone, structured body-fitted grids. It focuses on the structure and capabilities of MOSYS and the philosophy underlying its design. The system offers different levels of capability depending on the objectives of the user. It enables the applications engineer to quickly apply a variety of methods to geometrically complex problems. The methods developer can implement new algorithms in a simple form, and immediately apply them to problems of both theoretical and practical interest. And for the code builder it consitutes a toolkit for fast construction of CFD codes tailored to various purposes. These capabilities are illustrated through applications to a particularly complex problem encountered in aircraft propulsion systems, namely, the analysis of a landing aircraft in reverse thrust.
Computational model of cellular metabolic dynamics
DEFF Research Database (Denmark)
Li, Yanjun; Solomon, Thomas; Haus, Jacob M
2010-01-01
: intracellular metabolite concentrations and patterns of glucose disposal. Model variations were simulated to investigate three alternative mechanisms to explain insulin enhancements: Model 1 (M.1), simple mass action; M.2, insulin-mediated activation of key metabolic enzymes (i.e., hexokinase, glycogen synthase......Identifying the mechanisms by which insulin regulates glucose metabolism in skeletal muscle is critical to understanding the etiology of insulin resistance and type 2 diabetes. Our knowledge of these mechanisms is limited by the difficulty of obtaining in vivo intracellular data. To quantitatively...... distinguish significant transport and metabolic mechanisms from limited experimental data, we developed a physiologically based, multiscale mathematical model of cellular metabolic dynamics in skeletal muscle. The model describes mass transport and metabolic processes including distinctive processes...
Computational Granular Dynamics Models and Algorithms
Pöschel, Thorsten
2005-01-01
Computer simulations not only belong to the most important methods for the theoretical investigation of granular materials, but also provide the tools that have enabled much of the expanding research by physicists and engineers. The present book is intended to serve as an introduction to the application of numerical methods to systems of granular particles. Accordingly, emphasis is placed on a general understanding of the subject rather than on the presentation of the latest advances in numerical algorithms. Although a basic knowledge of C++ is needed for the understanding of the numerical methods and algorithms in the book, it avoids usage of elegant but complicated algorithms to remain accessible for those who prefer to use a different programming language. While the book focuses more on models than on the physics of granular material, many applications to real systems are presented.
Directory of Open Access Journals (Sweden)
Tel'noy Viktor Ivanovich
2012-10-01
Full Text Available Development of computer-assisted computer technologies and their integration into the academic activity with a view to the control of the academic performance within the framework of distance learning programmes represent the subject matter of the article. The article is a brief overview of the software programme designated for the monitoring of the academic performance of students enrolled in distance learning programmes. The software is developed on Delphi 7.0 for Windows operating system. The strength of the proposed software consists in the availability of the two modes of its operation that differ in the principle of the problem selection and timing parameters. Interim academic performance assessment is to be performed through the employment of computerized testing procedures that contemplate the use of a data base of testing assignments implemented in the eLearning Server media. Identification of students is to be performed through the installation of video cameras at workplaces of students.
Williams, Steven P.; Parrish, Russell V.
1992-01-01
Three-dimensional pictorial displays incorporating depth cues by means of stereopsis offer a potential means of presenting information in a natural way to enhance situational awareness and improve operator performance. Conventional computational techniques rely on asymptotic projection transformations and symmetric clipping to produce the stereo display. Implementation of two new computational techniques, as asymmetric clipping algorithm and piecewise linear projection transformation, provides the display designer with more control and better utilization of the effective depth-viewing volume to allow full exploitation of stereopsis cuing. Asymmetric clipping increases the perceived field of view (FOV) for the stereopsis region. The total horizontal FOV provided by the asymmetric clipping algorithm is greater throughout the scene viewing envelope than that of the symmetric algorithm. The new piecewise linear projection transformation allows the designer to creatively partition the depth-viewing volume, with freedom to place depth cuing at the various scene distances at which emphasis is desired.
J. Adam Wilson; Williams, Justin C.
2009-01-01
The clock speeds of modern computer processors have nearly plateaued in the past 5 years. Consequently, neural prosthetic systems that rely on processing large quantities of data in a short period of time face a bottleneck, in that it may not be possible to process all of the data recorded from an electrode array with high channel counts and bandwidth, such as electrocorticographic grids or other implantable systems. Therefore, in this study a method of using the processing capabilities of a ...
Dynamics and control of trajectory tubes theory and computation
Kurzhanski, Alexander B
2014-01-01
This monograph presents theoretical methods involving the Hamilton–Jacobi–Bellman formalism in conjunction with set-valued techniques of nonlinear analysis to solve significant problems in dynamics and control. The emphasis is on issues of reachability, feedback control synthesis under complex state constraints, hard or double bounds on controls, and performance in finite time. Guaranteed state estimation, output feedback control, and hybrid dynamics are also discussed. Although the focus is on systems with linear structure, the authors indicate how to apply each approach to nonlinear and nonconvex systems. The main theoretical results lead to computational schemes based on extensions of ellipsoidal calculus that provide complete solutions to the problems. These computational schemes in turn yield software tools that can be applied effectively to high-dimensional systems. Dynamics and Control of Trajectory Tubes: Theory and Computation will interest graduate and senior undergraduate students, as well as...
Dynamic detection for computer virus based on immune system
Institute of Scientific and Technical Information of China (English)
LI Tao
2008-01-01
Inspired by biological immune system,a new dynamic detection model for computer virus based on immune system is proposed.The quantitative description of the model is given.The problem of dynamic description for self and nonself in a computer virus immune system is solved,which reduces the size of self set.The new concept of dynamic tolerance,as well as the new mechanisms of gene evolution and gene coding for immature detectors is presented,improving the generating efficiency of mature detectors,reducing the false-negative and false-positive rates.Therefore,the difficult problem,in which the detector training cost is exponentially related to the size of self-set in a traditional computer immune system,is thus overcome.The theory analysis and experimental results show that the proposed model has better time efficiency and detecting ability than the classic model ARTIS.
A Survey on Graphical Programming Systems
Gurudatt Kulkarni; Sathyaraj. R
2014-01-01
Recently there has been an increasing interest in the use of graphics to help programming and understanding of computer systems. The Graphical Programming and Program Simulations are exciting areas of active computer science research that show the signs for improving the programming process. An array of different design methodologie s have arisen from research efforts and many graphical programming systems have been developed to address both general programming tasks and speci...
Computational Fluid and Particle Dynamics in the Human Respiratory System
Tu, Jiyuan; Ahmadi, Goodarz
2013-01-01
Traditional research methodologies in the human respiratory system have always been challenging due to their invasive nature. Recent advances in medical imaging and computational fluid dynamics (CFD) have accelerated this research. This book compiles and details recent advances in the modelling of the respiratory system for researchers, engineers, scientists, and health practitioners. It breaks down the complexities of this field and provides both students and scientists with an introduction and starting point to the physiology of the respiratory system, fluid dynamics and advanced CFD modeling tools. In addition to a brief introduction to the physics of the respiratory system and an overview of computational methods, the book contains best-practice guidelines for establishing high-quality computational models and simulations. Inspiration for new simulations can be gained through innovative case studies as well as hands-on practice using pre-made computational code. Last but not least, students and researcher...
Engineering Applications of Computational Fluid Dynamics: Volume 2
Directory of Open Access Journals (Sweden)
Maher A.R. Sadiq Al-Baghdadi
2013-01-01
Full Text Available Chapter 1: CFD Modeling of Methane Reforming in Compact Reformers. Meng Ni Chapter 2: FEM Based Solution of Thermo Fluid Dynamic Phenomena in Solid Oxide Fuel Cells (SOFCS. F. Arpino, A. Carotenuto, N. Massarotti, A. Mauro Chapter 3: Computational Fluid Dynamics in the Development of a 3D Simulator for Testing Pollution Monitoring Robotic Fishes. John Oyekan, Bowen Lu, Huosheng Hu Chapter 4: CFD Applications in Electronic Packaging. C.Y. Khor, Chun-Sean Lau, M.Z. Abdullah Chapter 5: CFD Simulation of Savonius Wind Turbine Operation. Jo?o Vicente Akwa, Adriane Prisco Petry Chapter 6: Intermittency Modelling of Transitional Boundary Layer Flows on Steam and Gas Turbine Blades. Erik Dick, Slawomir Kubacki, Koen Lodefier, Witold Elsner Chapter 7: Numerical Analysis of the Flow through Fitting in Air Conditioning Systems. N.C. Uz?rraga-Rodriguez, A. Gallegos-Mu?oz, J.M. Belman-Flores, J.C. Rubio-Arana Chapter 8: Design and Optimization of Food Processing Equipments using Computational Fluid Dynamics Modeling. N. Chhanwal and C. Anandharamakrishnan Chapter 9: Fuel and Intake Systems Optimization of a Converted LPG Engine: Steady and Unsteady in-Cylinder Flow CFD Investigations and Experiments Validation. M. A. Jemni, G. Kantchev, Z. Driss, M. S. Abid Chapter 10: Computational Fluid Dynamics Application for Thermal Management in Underground Mines. Agus P. Sasmito, Jundika C. Kurnia, Guan Mengzhao, Erik Birgersson, Arun S. Mujumdar Chapter 11: Computational Fluid Dynamics and its Applications. R.Parthiban, C.Muthuraj, A.Rajakumar
Performance Comparision of Dynamic Load Balancing Algorithm in Cloud Computing
Directory of Open Access Journals (Sweden)
Yogita kaushik
2016-08-01
Full Text Available Cloud computing as a distributed paradigm, it has the latent to make over a large part of the Cooperative industry. In cloud computing it’s automatically describe more technologies like distributed computing, virtualization, software, web services and networking. We review the new cloud computing technologies, and indicate the main challenges for their development in future, among which load balancing problem stands out and attracts our attention Concept of load balancing in networking and in cloud environment both are widely different. Load balancing in networking its complete concern to avoid the problem of overloading and under loading in any sever networking cloud computing its complete different its involves different elements metrics such as security, reliability, throughput, tolerance, on demand services, cost etc. Through these elements we avoiding various node problem of distributing system where many services waiting for request and others are heavily loaded and through these its increase response time and degraded performance optimization. In this paper first we classify algorithms in static and dynamic. Then we analyzed the dynamic algorithms applied in dynamics environments in cloud. Through this paper we have been show compression of various dynamics algorithm in which we include honey bee algorithm, throttled algorithm, Biased random algorithm with different elements and describe how and which is best in cloud environment with different metrics mainly used elements are performance, resource utilization and minimum cost. Our main focus of paper is in the analyze various load balancing algorithms and their applicability in cloud environment.
Aono, Masashi; Naruse, Makoto; Kim, Song-Ju; Wakabayashi, Masamitsu; Hori, Hirokazu; Ohtsu, Motoichi; Hara, Masahiko
2013-06-18
Biologically inspired computing devices and architectures are expected to overcome the limitations of conventional technologies in terms of solving computationally demanding problems, adapting to complex environments, reducing energy consumption, and so on. We previously demonstrated that a primitive single-celled amoeba (a plasmodial slime mold), which exhibits complex spatiotemporal oscillatory dynamics and sophisticated computing capabilities, can be used to search for a solution to a very hard combinatorial optimization problem. We successfully extracted the essential spatiotemporal dynamics by which the amoeba solves the problem. This amoeba-inspired computing paradigm can be implemented by various physical systems that exhibit suitable spatiotemporal dynamics resembling the amoeba's problem-solving process. In this Article, we demonstrate that photoexcitation transfer phenomena in certain quantum nanostructures mediated by optical near-field interactions generate the amoebalike spatiotemporal dynamics and can be used to solve the satisfiability problem (SAT), which is the problem of judging whether a given logical proposition (a Boolean formula) is self-consistent. SAT is related to diverse application problems in artificial intelligence, information security, and bioinformatics and is a crucially important nondeterministic polynomial time (NP)-complete problem, which is believed to become intractable for conventional digital computers when the problem size increases. We show that our amoeba-inspired computing paradigm dramatically outperforms a conventional stochastic search method. These results indicate the potential for developing highly versatile nanoarchitectonic computers that realize powerful solution searching with low energy consumption.
A Wearable Computing System for Dynamic Locating of Parking Spaces
Directory of Open Access Journals (Sweden)
Damian Mrugala
2010-07-01
Full Text Available This paper describes a dynamic locating system implemented in an autonomous wearable computing system for the automobile warehouse management application. Since the first prototype is developed as jacket [1], this prototype is miniaturized and therefore realized as holster which consists of several modules for identification, communication and localization. It is worn by employees during warehousing of automobiles. The modules collect data, which are used by the operating system to calculate the location of parking spaces dynamically.
Configurable software for satellite graphics
Energy Technology Data Exchange (ETDEWEB)
Hartzman, P D
1977-12-01
An important goal in interactive computer graphics is to provide users with both quick system responses for basic graphics functions and enough computing power for complex calculations. One solution is to have a distributed graphics system in which a minicomputer and a powerful large computer share the work. The most versatile type of distributed system is an intelligent satellite system in which the minicomputer is programmable by the application user and can do most of the work while the large remote machine is used for difficult computations. At New York University, the hardware was configured from available equipment. The level of system intelligence resulted almost completely from software development. Unlike previous work with intelligent satellites, the resulting system had system control centered in the satellite. It also had the ability to reconfigure software during realtime operation. The design of the system was done at a very high level using set theoretic language. The specification clearly illustrated processor boundaries and interfaces. The high-level specification also produced a compact, machine-independent virtual graphics data structure for picture representation. The software was written in a systems implementation language; thus, only one set of programs was needed for both machines. A user can program both machines in a single language. Tests of the system with an application program indicate that is has very high potential. A major result of this work is the demonstration that a gigantic investment in new hardware is not necessary for computing facilities interested in graphics.
Computational Fluid Dynamics. [numerical methods and algorithm development
1992-01-01
This collection of papers was presented at the Computational Fluid Dynamics (CFD) Conference held at Ames Research Center in California on March 12 through 14, 1991. It is an overview of CFD activities at NASA Lewis Research Center. The main thrust of computational work at Lewis is aimed at propulsion systems. Specific issues related to propulsion CFD and associated modeling will also be presented. Examples of results obtained with the most recent algorithm development will also be presented.
Improved Pyrolysis Micro reactor Design via Computational Fluid Dynamics Simulations
2017-05-23
NUMBER (Include area code) 23 May 2017 Briefing Charts 25 April 2017 - 23 May 2017 Improved Pyrolysis Micro-reactor Design via Computational Fluid... PYROLYSIS MICRO-REACTOR DESIGN VIA COMPUTATIONAL FLUID DYNAMICS SIMULATIONS Ghanshyam L. Vaghjiani* DISTRIBUTION A: Approved for public release...Approved for public release, distribution unlimited. PA Clearance 17247 Chen-Source (>240 references from SciFinder as of 5/1/17): Flash pyrolysis
A Common Platform for Graphical Models in R: The gRbase Package
Directory of Open Access Journals (Sweden)
Claus Dethlefsen
2005-12-01
Full Text Available The gRbase package is intended to set the framework for computer packages for data analysis using graphical models. The gRbase package is developed for the open source language, R, and is available for several platforms. The package is intended to be widely extendible and flexible so that package developers may implement further types of graphical models using the available methods. The gRbase package consists of a set of S version 3 classes and associated methods for representing data and models. The package is linked to the dynamicGraph package (Badsberg 2005, an interactive graphical user interface for manipulating graphs.In this paper, we show how these building blocks can be combined and integrated with inference engines in the special cases of hierarchical loglinear models. We also illustrate how to extend the package to deal with other types of graphical models, in this case the graphical Gaussian models.
Dynamic Routing Protocol for Computer Networks with Clustering Topology
Institute of Scientific and Technical Information of China (English)
无
1999-01-01
This paper presents a hierarchical dynamic routing protocol (HDRP) based on the discrete dynamic programming principle. The proposed protocol can adapt to the dynamic and large computer networks (DLCN) with clustering topology. The procedures for realizing routing update and decision are presented in this paper. The proof of correctness and complexity analysis of the protocol are also made. The performance measures of the HDRP including throughput and average message delay are evaluated by using of simulation. The study shows that the HDRP provides a new available approach to the routing decision for DLCN or high speed networks with clustering topology.
Brain Activities Associated with Graphic Emoticons: An fMRI Study
Yuasa, Masahide; Saito, Keiichi; Mukawa, Naoki
In this paper, we describe the brain activities that are associated with graphic emoticons by using functional MRI (fMRI). We use various types of faces from abstract to photorealistic in computer network applications. A graphics emoticon is an abstract face in communication over computer network. In this research, we created various graphic emoticons for the fMRI study and the graphic emoticons were classified according to friendliness and level of arousal. We investigated the brain activities of participants who were required to evaluate the emotional valence of the graphic emoticons (happy or sad). The experimental results showed that not only the right inferior frontal gyrus and the cingulate gyrus, but also the inferior and middle temporal gyrus and the fusiform gyrus, were found to be activated during the experiment. Forthermore, it is possible that the activation of the right inferior frontal gyrus and the cingulate gyrus is related to the type of abstract face. Since the inferior and middle temporal gyrus were activated, even though the graphic emoticons are static, we may perceive graphic emoticons as dynamic and living agents. Moreover, it is believed that text and graphics emoticons play an important role in enriching communication among users.
Dynamic computer simulation of the Fort St. Vrain steam turbines
Energy Technology Data Exchange (ETDEWEB)
Conklin, J.C.
1983-01-01
A computer simulation is described for the dynamic response of the Fort St. Vrain nuclear reactor regenerative intermediate- and low-pressure steam turbines. The fundamental computer-modeling assumptions for the turbines and feedwater heaters are developed. A turbine heat balance specifying steam and feedwater conditions at a given generator load and the volumes of the feedwater heaters are all that are necessary as descriptive input parameters. Actual plant data for a generator load reduction from 100 to 50% power (which occurred as part of a plant transient on November 9, 1981) are compared with computer-generated predictions, with reasonably good agreement.
Computational Psychometrics for Modeling System Dynamics during Stressful Disasters
Directory of Open Access Journals (Sweden)
Pietro Cipresso
2017-08-01
Full Text Available Disasters can be very stressful events. However, computational models of stress require data that might be very difficult to collect during disasters. Moreover, personal experiences are not repeatable, so it is not possible to collect bottom-up information when building a coherent model. To overcome these problems, we propose the use of computational models and virtual reality integration to recreate disaster situations, while examining possible dynamics in order to understand human behavior and relative consequences. By providing realistic parameters associated with disaster situations, computational scientists can work more closely with emergency responders to improve the quality of interventions in the future.
Directory of Open Access Journals (Sweden)
Heru Suhartanto
2011-07-01
Full Text Available One of application that needs high performance computing resources is molecular dynamic. There is some software available that perform molecular dynamic, one of these is a well known GROMACS. Our previous experiment simulating molecular dynamics of Indonesian grown herbal compounds show sufficient speed up on 32 nodes Cluster computing environment. In order to obtain a reliable simulation, one usually needs to run the experiment on the scale of hundred nodes. But this is expensive to develop and maintain. Since the invention of Graphical Processing Units that is also useful for general programming, many applications have been developed to run on this. This paper reports our experiments that evaluate the performance of GROMACS that runs on two different environment, Cluster computing resources and GPU based PCs. We run the experiment on BRV-1 and REM2 compounds. Four different GPUs are installed on the same type of PCs of quad cores; they are Gefore GTS 250, GTX 465, GTX 470 and Quadro 4000. We build a cluster of 16 nodes based on these four quad cores PCs. The preliminary experiment shows that those run on GTX 470 is the best among the other type of GPUs and as well as the cluster computing resource. A speed up around 11 and 12 is gained, while the cost of computer with GPU is only about 25 percent that of Cluster we built.
Engineering Design Graphics: Into the 21st Century
Harris, La Verne Abe; Meyers, Frederick
2007-01-01
Graphical plans for construction of machinery and architecture have evolved over the last 6,000 years beginning from hieroglyphics to drawings on printable media, from the "Golden Age" of engineering graphics to the innovation of computer graphics and prototyping. The evolution of engineering design graphics as a profession has also evolved. Years…
Engineering Design Graphics: Into the 21st Century
Harris, La Verne Abe; Meyers, Frederick
2007-01-01
Graphical plans for construction of machinery and architecture have evolved over the last 6,000 years beginning from hieroglyphics to drawings on printable media, from the "Golden Age" of engineering graphics to the innovation of computer graphics and prototyping. The evolution of engineering design graphics as a profession has also evolved. Years…
Numerical Integration with Graphical Processing Unit for QKD Simulation
2014-03-27
existing and proposed Quantum Key Distribution (QKD) systems. This research investigates using graphical processing unit ( GPU ) technology to more...Time Pad GPU graphical processing unit API application programming interface CUDA Compute Unified Device Architecture SIMD single-instruction-stream...and can be passed by value or reference [2]. 2.3 Graphical Processing Units Programming with graphical processing unit ( GPU ) requires a different
Dynamics of number systems computation with arbitrary precision
Kurka, Petr
2016-01-01
This book is a source of valuable and useful information on the topics of dynamics of number systems and scientific computation with arbitrary precision. It is addressed to scholars, scientists and engineers, and graduate students. The treatment is elementary and self-contained with relevance both for theory and applications. The basic prerequisite of the book is linear algebra and matrix calculus. .
Dynamic enhanced computed tomographic findings of a perirenal capillary hemangioma
Energy Technology Data Exchange (ETDEWEB)
Lee, Jung Min; Kim, Sang Won; Kim, Hyun Cheol; Yang, Dal Mo; Ryu, Jung Kyu; Lim, Sung Jig [Kyung Hee University Hospital at Gangdong, Seoul (Korea, Republic of)
2016-05-15
Hemangiomas are benign mesenchymal neoplasms that rarely occur in the kidney and perirenal space. Perirenal hemangiomas can mimic the appearance of exophytic renal cell carcinoma or various retroperitoneal tumors. We report a case of perirenal hemangioma detected by dynamic enhanced computed tomography in a 43-year-old female.
Microchannel Emulsification: From Computational Fluid Dynamics to Predictive Analytical Model
Dijke, van K.C.; Schroën, C.G.P.H.; Boom, R.M.
2008-01-01
Emulsion droplet formation was investigated in terrace-based microchannel systems that generate droplets through spontaneous Laplace pressure driven snap-off. The droplet formation mechanism was investigated through high-speed imaging and computational fluid dynamics (CFD) simulation, and we found g
An Assessment of Productive Computational Fluid Dynamics for Aerodynamic Design
2008-01-01
PANAIR [7]) to marching techniques (like ZEUS [8] and parabolized Navier-S tokes codes) and full-field, elliptical, Computational Fluid Dynamics (CFD...undeflected case), but individual representations were required to create each deflection angle for the bent nose configuration. Figure 1. Three
Applied Nonlinear Dynamics Analytical, Computational, and Experimental Methods
Nayfeh, Ali H
1995-01-01
A unified and coherent treatment of analytical, computational and experimental techniques of nonlinear dynamics with numerous illustrative applications. Features a discourse on geometric concepts such as Poincaré maps. Discusses chaos, stability and bifurcation analysis for systems of differential and algebraic equations. Includes scores of examples to facilitate understanding.
Delivering Interactive Multimedia Services in Dynamic Pervasive Computing Environments
Hesselman, C.; Cesar Garcia, P.S.; Vaishnavi, I.; Boussard, M.; Kernchen, R.; Meissner, S.; Spedalieri, A.; Sinfreu, A.; Raeck, C.
2008-01-01
This paper introduces a distributed system for next generation multimedia support in dynamically changing pervasive computing environments. The overall goal is to enhance the experience of mobile users by intelligently adapting the way a service is presented, in particular by adapting the way the us
International Conference on Numerical Grid Generation in Computational Fluid Dynamics
1989-04-30
Grun Convex Computer Corporation Brunnenstr. 17 701 Piano Road 8049 Bachenhausen Richardson Germany TX 75081 Chunyuan Gu J. E.Holcomb Dept. of Gas...Lab System Dynamics Inc. L-95, PO Box 808 1211 N.W. 10th Avenue Livermore, CA 94550 Gainesville FL 32601 Bernadette Palmero Azine Renzo Universite de
Modelling Emission from Building Materials with Computational Fluid Dynamics
DEFF Research Database (Denmark)
Topp, Claus; Nielsen, Peter V.; Heiselberg, Per
This paper presents a numerical model that by means of computational fluid dynamics (CFD) is capable of dealing with both pollutant transport across the boundary layer and internal diffusion in the source without prior knowledge of which is the limiting process. The model provides the concentration...
Computational Fluid Dynamics and Building Energy Performance Simulation
DEFF Research Database (Denmark)
Nielsen, Peter Vilhelm; Tryggvason, T.
1998-01-01
An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution will be introduced for improvement of the predictions of both the energy consumption and the indoor environment. The building energy performance...
Computational fluid dynamics applications to improve crop production systems
Computational fluid dynamics (CFD), numerical analysis and simulation tools of fluid flow processes have emerged from the development stage and become nowadays a robust design tool. It is widely used to study various transport phenomena which involve fluid flow, heat and mass transfer, providing det...
Kin, Taichi; Nakatomi, Hirofumi; Shono, Naoyuki; Nomura, Seiji; Saito, Toki; Oyama, Hiroshi; Saito, Nobuhito
2017-06-22
Simulation and planning of surgery using a virtual reality model is becoming common with advances in computer technology. In this study, we conducted a literature search to find trends in virtual simulation of surgery for brain tumors. A MEDLINE search for "neurosurgery AND (simulation OR virtual reality)" retrieved a total of 1,298 articles published in the past 10 years. After eliminating studies designed solely for education and training purposes, 28 articles about the clinical application remained. The finding that the vast majority of the articles were about education and training rather than clinical applications suggests that several issues need be addressed for clinical application of surgical simulation. In addition, 10 of the 28 articles were from Japanese groups. In general, the 28 articles demonstrated clinical benefits of virtual surgical simulation. Simulation was particularly useful in better understanding complicated spatial relations of anatomical landmarks and in examining surgical approaches. In some studies, Virtual reality models were used on either surgical navigation system or augmented reality technology, which projects virtual reality images onto the operating field. Reported problems were difficulties in standardized, objective evaluation of surgical simulation systems; inability to respond to tissue deformation caused by surgical maneuvers; absence of the system functionality to reflect features of tissue (e.g., hardness and adhesion); and many problems with image processing. The amount of description about image processing tended to be insufficient, indicating that the level of evidence, risk of bias, precision, and reproducibility need to be addressed for further advances and ultimately for full clinical application.
Computational Fluid Dynamics Demonstration of Rigid Bodies in Motion
Camarena, Ernesto; Vu, Bruce T.
2011-01-01
The Design Analysis Branch (NE-Ml) at the Kennedy Space Center has not had the ability to accurately couple Rigid Body Dynamics (RBD) and Computational Fluid Dynamics (CFD). OVERFLOW-D is a flow solver that has been developed by NASA to have the capability to analyze and simulate dynamic motions with up to six Degrees of Freedom (6-DOF). Two simulations were prepared over the course of the internship to demonstrate 6DOF motion of rigid bodies under aerodynamic loading. The geometries in the simulations were based on a conceptual Space Launch System (SLS). The first simulation that was prepared and computed was the motion of a Solid Rocket Booster (SRB) as it separates from its core stage. To reduce computational time during the development of the simulation, only half of the physical domain with respect to the symmetry plane was simulated. Then a full solution was prepared and computed. The second simulation was a model of the SLS as it departs from a launch pad under a 20 knot crosswind. This simulation was reduced to Two Dimensions (2D) to reduce both preparation and computation time. By allowing 2-DOF for translations and 1-DOF for rotation, the simulation predicted unrealistic rotation. The simulation was then constrained to only allow translations.
Dynamic Distribution Model with Prime Granularity for Parallel Computing
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
Dynamic distribution model is one of the best schemes for parallel volume rendering. However, in homogeneous cluster system, since the granularity is traditionally identical, all processors communicate almost simultaneously and computation load may lose balance. Due to problems above, a dynamic distribution model with prime granularity for parallel computing is presented.Granularities of each processor are relatively prime, and related theories are introduced. A high parallel performance can be achieved by minimizing network competition and using a load balancing strategy that ensures all processors finish almost simultaneously. Based on Master-Slave-Gleaner (MSG) scheme, the parallel Splatting Algorithm for volume rendering is used to test the model on IBM Cluster 1350 system. The experimental results show that the model can bring a considerable improvement in performance, including computation efficiency, total execution time, speed, and load balancing.
Verhoeven, G. J.
2017-08-01
Since a few years, structure-from-motion and multi-view stereo pipelines have become omnipresent in the cultural heritage domain. The fact that such Image-Based Modelling (IBM) approaches are capable of providing a photo-realistic texture along the threedimensional (3D) digital surface geometry is often considered a unique selling point, certainly for those cases that aim for a visually pleasing result. However, this texture can very often also obscure the underlying geometrical details of the surface, making it very hard to assess the morphological features of the digitised artefact or scene. Instead of constantly switching between the textured and untextured version of the 3D surface model, this paper presents a new method to generate a morphology-enhanced colour texture for the 3D polymesh. The presented approach tries to overcome this switching between objects visualisations by fusing the original colour texture data with a specific depiction of the surface normals. Whether applied to the original 3D surface model or a lowresolution derivative, this newly generated texture does not solely convey the colours in a proper way but also enhances the smalland large-scale spatial and morphological features that are hard or impossible to perceive in the original textured model. In addition, the technique is very useful for low-end 3D viewers, since no additional memory and computing capacity are needed to convey relief details properly. Apart from simple visualisation purposes, the textured 3D models are now also better suited for on-surface interpretative mapping and the generation of line drawings.
Computational dynamics for robotics systems using a non-strict computational approach
Orin, David E.; Wong, Ho-Cheung; Sadayappan, P.
1989-01-01
A Non-Strict computational approach for real-time robotics control computations is proposed. In contrast to the traditional approach to scheduling such computations, based strictly on task dependence relations, the proposed approach relaxes precedence constraints and scheduling is guided instead by the relative sensitivity of the outputs with respect to the various paths in the task graph. An example of the computation of the Inverse Dynamics of a simple inverted pendulum is used to demonstrate the reduction in effective computational latency through use of the Non-Strict approach. A speedup of 5 has been obtained when the processes of the task graph are scheduled to reduce the latency along the crucial path of the computation. While error is introduced by the relaxation of precedence constraints, the Non-Strict approach has a smaller error than the conventional Strict approach for a wide range of input conditions.
Explore the Design and Implementation of C #-based Dynamic Display Graphics%基于C#的动态图形显示设计与实现探讨
Institute of Scientific and Technical Information of China (English)
王大龙
2013-01-01
基于C#图形控件，本文设定一个新的动态图形显示控件DynamicImageButton，将图像数据信息以多维数组的方式存储，建立合适的属性信息，通过动态数据的透明与动态数据帧控制的算法设计的研究，从而实现图像透明与动态控制。%Based on the c # graphical control, this paper set up a new dynamic graphic display control DynamicImageButton, the image data stored in the form of multidimensional arrays, establish proper attribute information, through the dynamic data and dynamic data of the frame control algorithm design of study, so as to realize image transparent and dynamic control.
Towards Dynamic Remote Data Auditing in Computational Clouds
Directory of Open Access Journals (Sweden)
Mehdi Sookhak
2014-01-01
Full Text Available Cloud computing is a significant shift of computational paradigm where computing as a utility and storing data remotely have a great potential. Enterprise and businesses are now more interested in outsourcing their data to the cloud to lessen the burden of local data storage and maintenance. However, the outsourced data and the computation outcomes are not continuously trustworthy due to the lack of control and physical possession of the data owners. To better streamline this issue, researchers have now focused on designing remote data auditing (RDA techniques. The majority of these techniques, however, are only applicable for static archive data and are not subject to audit the dynamically updated outsourced data. We propose an effectual RDA technique based on algebraic signature properties for cloud storage system and also present a new data structure capable of efficiently supporting dynamic data operations like append, insert, modify, and delete. Moreover, this data structure empowers our method to be applicable for large-scale data with minimum computation cost. The comparative analysis with the state-of-the-art RDA schemes shows that the proposed scheme is secure and highly efficient in terms of the computation and communication overhead on the auditor and server.