Computer Graphics Laboratory

Gennadiy Nikishkov Professor	Kamen Kanev Associate Professor

Members of the Computer Graphics Laboratory perform research in physics-based modeling of different phenomena, their visualization and animation. Innovative approaches to graphical user interfaces and direct interaction methods, modeling, rendering, simulation and scientific visualization are under development. Created mathematical models are used for graphical representation of natural processes. Research areas include: Visualization of surface and volume data, which results from finite element, boundary element and finite difference modeling. Development of video-based face tracking interface for disabled people. Augmented reality interface suitable for use in medical physics measurements. Nanomechanics modeling. Numerical approach is used for modeling of selfpositioning micro- and nanostructures with large translations and rotations. Physics-based animation of liquids. Using graphics processing unit for animation and and general purpose computations. Surface-based interactions and interfaces. Dynamic digital content for consumer awareness. Virtual reality with direct interaction interfaces. Digital enhancement of mobile robot environments. Research on cluster patterns for direct position sensing. Innovative technologies for the intelligent support of reading. Methods and systems for support of collaborative learning in a dynamic group environment. Professors of the Computer Graphics Laboratory deliver courses in Computer Graphics, Algorithms and Data Structures, Numerical Analysis, Advanced Algorithms, Modeling and Visualization. Graduation projects and SCCP are related to computer modeling, human-computer interactions, visualization and animation and to Web technologies.

Refereed Journal Papers

[kanev-01:2005]	K. Kanev and S. Kimura. Direct Point-and-Click Functionality for Printed Materials. The Journal of Three Dimensional Images, 20(2):51-59, 2006.
	When interacting with computers we point-and-click with the mouse in a most natural way. However, if we attempt to extend this to paper based documents, a relatively bulky and expensive digitizing devices become necessary. Yet very compact, handheld image acquisition devices are readily available, but cannot be directly used in point-and-click interfaces since they do not provide any coordinate feedback. Here we present a robust and reliable method for enhancing printed documents with an unobtrusive digital data layer that blends with the document content and serves as a virtual digitizer for providing position and orientation feedback. Consequently a point-and-click interface can be easily implemented with an inexpensive handheld image acquisition device, such as a USB camera that will read small portions of the digital layer, decode the coordinates and provide position and orientation feedback.
[niki-01:2005]	G.P.Nikishkov, Y.Nishidate, T.Ohnishi, and P.O.Vaccaro. Effect of material anisotropy on the self-positioning of nanostructures. Nanotechnology, 17:1128-1133, 2006.
	An experimental and numerical investigation of the effect of material anisotropy on the self-positioning of epitaxial nanostructures has been performed. The self-positioning occurs due to a lattice mismatch between two epitaxial material layers (GaAs and In0.2Ga0.8As) of a hinge. Both materials have cubic crystal symmetry and possess anisotropic mechanical properties. The dependence of the hinge curvature radius on the material orientation angle was obtained experimentally by creating self-positioning hinges with different angles between the hinge axis and material crystallographic axes. The same self-positioning structures were modelled by solving geometrically nonlinear problems with the help of the finite element method. Experimental and numerical values of the hinge curvature radius are in qualitative agreement. It is found that material anisotropy significantly affects the shape of self-positioning structures.
[niki-02:2005]	G.P.Nikishkov. Object oriented design of a finite element code in Java. Computer Modeling in Engineering and Sciences, 11:81-90, 2006.
	This paper presents the object oriented approach to programming the finite element method using the Java language. The developed finite element code consists of ten Java packages. Three main methods are related to generation of finite element models, solution of elastic and elastic-plastic boundary value problems, and visualization of models and solution results. Object oriented model of the code is described. It is demonstrated that Java 1.5 new features are useful in development of the finite element code. Java 3D is used for visualization of models and results.

Refereed Proceeding Papers

[kanev-02:2005]	K. Kanev and S. Kimura. Linking to Dynamic Digital Content for Health Awareness. In Proceedings of the Joint Meeting of International Workshop on E-health and 2nd International Conference on Ubiquitous Healthcare 2005, pages 37-40, 2005.
	Increasing health awareness makes people pay more attention to the quality content and ingredients of the foods and drinks they consume. While some basic content and health related information is usually printed on food packages, cans and bottles, space limits rarely allow for full details. Once a product is on the market no further updates are possible and newly discovered health effects and warnings cannot be directly communicated to the consumers. In this work we introduce the idea of dynamic digital content, directly linked to product package surface and accessible through common optical recognition devices such as a USB cameras or mobile phones. This will allow instant access to up-to-date information and health warnings during the entire shelf life of the product, which may be up to several years. We also discuss a personalized optical recognition device, which will contain the consumer's health profile and could make food and drink recommendations accordingly. Suggested way of implementing such a system is through the Cluster Pattern Interface (CLUSPI), invented and recently patented by the authors. In contrast to barcodes that stand out and require dedicated area of significant size, our method uses cluster patterns, which are virtually invisible for naked human eye and can be smoothly integrated with content printed on package surfaces.
[kanev-03:2005]	K. Kanev and S. Kimura. Print Based Interfaces with Direct Point and Click Functionality. In Proceedings of the Eighth Int. Conf. on Human and Computers HC2005, pages 128-135, 2005.
	In this work we discuss methods for enhancing printed documents with layers of digital data that blend with the document content and serve as a 'virtual digitizer' for providing position and orientation feedback. Consequently a point and click interface can be implemented with an inexpensive handheld image acquisition device, such as an USB camera that will read small portions of the digital layer, decode coordinates and provide position and orientation feedback. This work is based on an innovative technology, recently patented by the authors.
[kanev-04:2005]	K. Kanev and S. Kimura. Surface Based Spatial Awareness for Mobile Robots. In Proceedings of the Eleventh International Symposium on Artificial Life and Robotics AROB'06, 2006.
	A method for enhancing physical objects and their surfaces with digital data layers that are barely visible to the naked human eye but could be reliably read and decoded by mobile robot vision optics is proposed. Easily accessible spatial data is directly encoded and blended into mobile robot environments and links to object properties and other parameters are established and could be used for developing spatial awareness models for mobile robots. Potential commercial applications are automated storage facilities and assembly line environments. In education, robot models can be enhanced with precise positioning capabilities by a simple wireless camera and a digitally encoded tabletop surface.
[kanev-05:2005]	K. Kanev, K. Matsubara, S. Takase, J. Matsumoto, and A. Tezuka. Development of CAE Software with GUI for Inkjet Analysis. In Proceedings of the 55th Nat. Conf. of Theoretical & Applied Mechanics 2006, pages 497-498, 2006.
	Is nearly impossible to carry out the development of micro-fluid devises such as micro-reactors, micro-inkjets, and micro-pumps, without introducing numerical simulations on free surface flows and solid-thermal-fluid coupling analyses, which are usually ill-conditioned problems, accompanied with very rapid inner flows in a complicatedly shaped domain under serious density differences among gas, fluid and solid. We developed CAE software with GUI for experimental research and engineering of inkjet two-phase flow behaviour, following our new VOF (Volume of Fluid) scheme based on the stabilizedbubble-function FEM (Finite Element Method) for two-phase flows under severe conditions. The software is expected to become an indispensable tool for parameter studies during the development of high performance micro-inkjet devices.
[kanev-06:2005]	K. Kanev, N. Kamiya, and N. Mirenkov. Communicating Mathematics Through Digitally Enhanced Documents. In Proceedings of CMDE2006, 2006.
	In this work a method and corresponding technological means for digital enhancement of existing materials in mathematics and related subjects with additional content and functionality that could enhance comprehension by bringing in self-explanatory components, multiple views and information sources on demand are proposed. Existing technologies for linking digital information to paper based documents are analyzed and direct interaction methods and corresponding implementations are investigated. Applicability of the innovative Cluster Pattern Interface (CLUSPI) for embedding digital content and references to digital texts, images, sound, video and other multimedia content into traditional educational materials for math studies is evaluated. Analysis of existing educational materials for math classes is conducted and appropriate procedures for preparation of experimental educational content are clarified. Possibilities for enhancing learning and comprehension through selfexplanatory components, multiple views and information sources on demand are explored and samples based on exiting and original math lessons printed content, additional digital content and corresponding links and references are designed. Small-scale educational experiments in controlled laboratory environment are planned where the sample digitally enhanced educational content will be used for verification of our method. Obtained results are expected to serve as a basis for building practical implementations that could be directly used for more efficient communication of math concepts and ideas in the course of the teaching process and elsewhere.
[kanev-07:2005]	K. Kanev and T. Orr. Enhancing Paper Documents with Direct Access to Multimedia for an Intelligent Support of Reading. In Proceedings of IEEE Conference on the Convergence of Technology and Professional Communication (IPCC 2006), 2006.
	This paper presents a brief overview of recent technologies that connect multimedia to paper and identifies features and functionalities desirable for the support of reading. An innovative Cluster Pattern Interface (CLUSPIR) is described, along with its potential for addressing the specific needs of readers of paper documents. We argue that by identifying and properly addressing the specific information needs of readers of paper documents based on reader requirements found in research literature, advanced levels of support can be accomplished with innovative technological achievements, which can provide a more intelligent way to improve a reader's engagement with paper text.
[kanev-08:2005]	J. Brine, D. Turk, and K. Kanev. Supporting Reading Jigsaws with Print-based Digital Content Interfaces. In JALTCALL 2006 International Conference, 2006.
	This paper investigates the potential pedagogic application of digitallyenhanced print-based interfaces for the strategic support of reading. A combined individual and social jigsaw reading activity was devised to extend student reading skills beyond the comprehension of basic document content. The project team focused on activities that required students to read and process complex authentic technical texts, gathered student feedback and devised enhancements of traditional jigsaw activities accordingly. The findings of this research have direct implications for the collaborative application of Cluster Pattern Interface (CLUSPI)-enhanced jigsaw reading tasks within a large class environment.
[kanev-09:2005]	D. Turk, J. Brine, and K. Kanev. Print-Based Digital Content Interfaces for Social Reading Activities. In Proceedings of the 6th IEEE International Conference on Advanced Learning Technologies (ICALT 2006), 2006.
	This paper outlines the pedagogic application of digitally-enhanced printbased interfaces for the support of reading. A combined individual and social jigsaw reading activity was devised to extend student reading skills beyond the comprehension of basic document content. The project team aimed to design and develop an activity that required students to read and process complex authentic technical texts. Informed by student feedback, this research project evaluated the benefits of enhancing the activity with the Cluster Pattern Interface (CLUSPI), patented by Kamen Kanev and Shigeo Kimura, to facilitate the students' reading comprehension and improve their multiliteracy skills. CLUSPI is a cluster pattern-based encoding scheme that allows digitally encoded information to be embedded in a layer of clustered graphical objects on printed documents. CLUSPI can expand the application of ubiquitous multimedia - providing students with additional up-to-date information and access to various language learning tools through a point-and-click interface.
[kanev-10:2005]	D. Turk, J. Brine, and K. Kanev. Social Reading Activities Using Print-Based Digital Content Interfaces. In Proceedings of the 2nd IASTED International Conference on Education and Technology, 2006.
	This paper investigates the potential pedagogic application of digitallyenhanced print-based interfaces for the support of reading. We devised a combined individual and social jigsaw reading activity in order to extend student reading skills beyond basic document content comprehension. Using the modified jigsaw approach, students read complex authentic technical texts to sequence a text. The students were observed during the activity and they were asked to report the computer-based applications that they used or would have liked to use to support their reading of the text. We then evaluated the potential pedagogic application of the Cluster Pattern Interface (CLUSPI) for enhancing the activity. CLUSPI is a cluster pattern-based encoding scheme that allows digitally encoded information to be embedded in a layer of clustered graphical objects on printed documents. Such digitally-enhanced paper materials might provide students with additional up-to-date information and timely access to various language learning tools.
[niki-03:2005]	G.P.Nikishkov and P.O.Vaccaro. Finite element solution of geometrically nonlinear anisotropic problems. In Proceedings of Int. Workshop on Development and Advancement of Computational Mechanics, pages 149-158, Kobe, 22-23 April 2005.
	A finite element procedure has been developed for the solution of threedimensional geometrically nonlinear anisotropic problems with small strains and large rotations and translations. Updated Lagrangian formulation is used with controlling strains and stresses in material coordinate frames at element integration points. Equilibrium iterations at each step are performed according to the Newton-Raphson method. Hexahedral 20-node elements are used for discretization. The developed finite element procedure is applied to modeling of self-positioning microstructures and nanostructures. A multilayer structure is formed with the molecular beam epitaxy method. After etching out a sacrificial material layer, the structure is self-positioned due to different lattice periods of material layers. A series of finite element solutions is performed for an anisotropic self-positioning hinged microstructure. Dependance of the hinge curvature radius on the material orientation angle correlates with experimental data.
[niki-04:2005]	Y.Nishidate and G.P.Nikishkov. Fast water animation using the wave equation with damping. In V.S.Sunderam et al, editor, LNCS Volume 3515, Procs 5th Int. Conf. on Computational Science ICCS 2005, pages 232-229, Atlanta, GA, USA, 22-25 May 2005.
	A simple method for animation of water waves is presented. The twodimensional wave equation with damping is used to obtain a finite difference scheme for height distribution. A computational procedure employs explicit time integration. High frame rates are typically obtained for real-time animation of water waves.
[niki-05:2005]	G.P.Nikishkov. Adaptive surface modeling using a quadtree of quadratic finite elements. In V.S.Sunderam et al, editor, LNCS Volume 3515, Procs 5th Int. Conf. on Computational Science ICCS 2005, pages 306-313, Atlanta, GA, USA, 22-25 May 2005.
	This article presents special quadrilateral quadratic refinement elements, which provide geometry and field continuity across Tjunctions where two elements are connected to one side of a larger quadrilateral. The main idea in element refinement is to place one or more nodes outside the element area and to modify element shape functions in order to maintain continuity at refinement edges. Special refinement elements allow one to adaptively refine a mesh in such a way that it fits a quadtree data structure. An algorithm of surface modeling starts with a coarse mesh of quadratic quadrilateral elements. Adaptive mesh refinement is done in an iterative manner. At each iteration, the finite element equation system is solved to provide nodal locations with minimization of global approximation error. Elements with excessive local errors are split into four new elements. The mesh refinement iteration process is terminated when no element splits occur. The created mesh of quadratic quadrilaterals can be used directly in finite element analysis.
[niki-06:2005]	V.Graveleau, N.N.Mirenkov, and G.P.Nikishkov. A Head-Controlled User Interface. In Proceedings of the 8th Int. Conference on Human and Computer HC 2005, pages 306-311, Aizu-Wakamatsu, 31 Aug.-2 Sep. 2005.
	In this paper, we present an implementation of a head-controlled real-time human-computer interface that does not require using hands. This kind of interface may be valuable for disabled people or in cases where hands are busy with other tasks. Usual video-camera is employed for tracking head movements. Position of the eyes is determined with the use of image analysis. Head movements are mapped to cursor displacements. Nodding and head-shaking model left and right mouse clicks. Experiments show that the system behaves satisfactory even for usual web-camera frame rates (15fps), and small images (32040). It consumes small percentage of CPU resources allowing other processes to run smoothly.

Grants

[kanev-11:2005]	K. Kanev. Investigation of Cluster Pattern Methods for Absolute Position Recognition, 2005.
[kanev-12:2005]	K. Kanev, J. Brine, D. Turk, and T. Orr. Innovative Technologies for the Intelligent Support of Reading, 2005.
[kanev-13:2005]	K. Kanev, Tei S., Mirenkov N., and Yamauchi K. New Methods and Technologies for Enhancing and Optimizing Inspection Procedures at TEPCO Facilities, 2005.

Academic Activities

[niki-07:2005]	Gennadiy Nikishkov, 2005. Member of the Editorial Board, International Journal 'Computer Modeling in Engineering and Sciences'.
[niki-08:2005]	Gennadiy Nikishkov, Dec. 2005. Member of the Organizing Committee, Int. Conf. on Computational and Experimental Engineering and Sciences ICCES 2005, India.
[niki-09:2005]	Gennadiy Nikishkov, Feb. 2006. Member of the Program Committee, Int. Conf. on Computer Graphics Theory and Applications GRAPP 2006, Spain.
[niki-10:2005]	Gennadiy Nikishkov, 2005. Reviewer, Computer Modeling in Engineering and Sciences.
[niki-11:2005]	Gennadiy Nikishkov, 2005. Reviewer, Computers and Structures.
[niki-12:2005]	Gennadiy Nikishkov, 2005. Reviewer, Applied Physics Letters.
[niki-13:2005]	Gennadiy Nikishkov, 2005. Reviewer, Engineering Fracture Mechanics.

Patents

[kanev-14:2005]	K. Kanev and S. Kimura. Digital Information Carrier, Japanese Patent No 3635374, November 2005.
[kanev-15:2005]	K. Kanev and S. Kimura. Digital Information Carrier, Patent Application No 10/559607, November 2005.
[kanev-16:2005]	K. Kanev and S. Kimura. Digital Information Carrier, Patent Application No 2527961, November 2005.
[kanev-17:2005]	K. Kanev and S. Kimura. Digital Information Carrier, Patent Application No 2004295871, November 2005.
[kanev-18:2005]	K. Kanev and S. Kimura. Digital Information Carrier, Patent Application No 20040799690, November 2005.

Ph.D and Other Theses

[niki-14:2005]	Youhei Nishidate. Master Thesis: Finite element modeling and visualization of flexible structures, University of Aizu, 2005. Thesis Advisor: Gennadiy Nikishkov
[niki-15:2005]	Katsuhiro Numata. Master Thesis: Animation of fluids using multiphase flow approach, University of Aizu, 2005. Thesis Advisor: Gennadiy Nikishkov
[niki-16:2005]	Syunichi Fujita. Graduation Thesis: Multiple view reconstruction of textured models, University of Aizu, 2005. Thesis Advisor: Gennadiy Nikishkov
[niki-17:2005]	Jyunichi Hosoi. Graduation Thesis: Generation of quadrilateral finite element meshes, University of Aizu, 2005. Thesis Advisor: Gennadiy Nikishkov
[niki-18:2005]	Tsukasa Ito. Graduation Thesis: Car parking simulation using Java 3D, University of Aizu, 2005. Thesis Advisor: Gennadiy Nikishkov
[niki-19:2005]	Tetsuya Nagayama. Graduation Thesis: Comparison of collision detection methods, University of Aizu, 2005. Thesis Advisor: Gennadiy Nikishkov
[niki-20:2005]	Ryuusuke Nakamura. Graduation Thesis: A visual guide for the University, University of Aizu, 2005. Thesis Advisor: Gennadiy Nikishkov

2007 THE UNIVERSITY OF AIZU ALL RIGHTS RESERVED