bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling and animating faces using scanned data
Authors: Waters Keith , Terzopoulos Demetri 
Published: November 2006

AbstractThis paper extends a physically‐based approach to the realistic modelling and animation of human heads using scanned data. A three‐step procedure is proposed which begins with geometry and colour data acquired from a subject's head using a radial laser scanner, continues with the construction of a 3D model of the head with complete colour texture mapping, and culminates in real‐time, interactive facial animation. First, an adaptive meshing technique is described that creates non‐uniform facial meshes from the densely sampled data. These geometrically accurate facial meshes adapt to features of interest in the data, increasing polygon density over articulate face regions and areas of high curvature. Secondly, the mesh is transformed into a physically‐based head model of the subject. This incorporates a physical approximation to facial tissue and a set of anatomically‐motivated facial muscle actuators. Finally, these components are integrated in a facial modelling and animation system.
Creative parameter selection for volume visualization
Authors: Giertsen Christopher 
Published: November 2006

AbstractMost of the available algorithms for scalar volume visualization offer predefined techniques such as display of volumetric regions defined by scalar threshold values. The regions can usually be drawn opaque or transparent or appear in combinations. This paper presents an implementation of a volume visualization concept where several modelling and rendering techniques can be applied in any combination, mainly bounded by the creativity of the user.The concept is based on the use of a model for light scattering in a field of varying density emitters, and the use of fixed visual references to improve readability and disambiguate interpretation. An image is computed by means of an interval‐based mapping from scalar range to visual parameters. Each interval has a set of associated parameters, such as colour and attenuation. In addition, each interval of the scalar range must be mapped into relative density by means of a transfer function which is selected in a ‘natural way’ depending on application. A methodology is suggested which enable the piecewise transfer functions to be easily determined.A prototype user‐interface for the mapping from scalar values to visual parameters is demonstrated. The interface is easy to use for the beginner, while it also encourages creativity and intuition in the process of selecting parameters.
Infinite reflection models for the visual arts
Authors: Inakage Masa 
Published: November 2006

AbstractArtists do not always pursue photographic realism. The image abstraction and deformation of three‐dimensional scenes are methods to communicate ideas. Images are the visual interpretation of real life or imaginary scenes. This paper describes the idea of an infinite reflection model in which synthetic objects to be rendered are surrounded by closed reflective surfaces. The closed mirror surfaces create the ‘feedback’ effect which deforms objects inside the reflective space. Lens distortion effects are achieved by surrounding infinitely reflective curved surfaces. This technique provides a new visual tool for artists and graphic designers.
Integrated software, process, algorithm and application visualization
Authors: Friedell Mark , Kochhar Sandeep , Lapolla Mark Vincent , Marks Joe 
Published: November 2006

AbstractWe present a unifying view of visualization in which comprehensive support for software, algorithm, process and application (including scientific) visualizations is treated as an essential component of the computing environment. We describe our recent work toward making this view a reality: a tool for computer‐assisted design of visualizations and a technique for monitoring a computational process in a non‐invasive fashion.
Visualizing complex biological interactions in the soil ecosystem
Authors: Liddell Craig M. , Hansen Deren 
Published: November 2006

AbstractScientific visualization is proving very promising for the study of biological interactions at the organismal level in porous opaque media. We present our research in visualizing and modelling fungal and plant root development and interactions in the soil. Because the dynamic biological properties of the soil ecosystem can be observed in only the crudest fashion, we emphasize the fundamental link between visualization and modelling. Our research focuses along the parallel lines of imaging actual phenomena and of modelling these same phenomena. Many soil organisms, such as plants and fungi, exist predominately in a vegetative state which is highly branched, non‐random and non‐homogeneous. This structure itself is important to dynamic process such as parasitism of one organism by another, yet due to the opacity of soil, structure is difficult to observe and dynamic interactions are impossible to observe. The modelling of growth patterns and interactions of fungi and plant roots with the concomitant use of visualization and rigorous model validation provides the best method to build a working concept, which is faithful to the spatial organization of the real world. We hypothesize that the genetic determinants controlling growth and interactions operate both inside and outside the soil environment. We conclude that visualization provides a means by which spatial extrapolation of laboratory observations may be made to the real world, providing both model validation and a means to build mechanistically‐based hypotheses about different types of dynamic phenomena in the soil ecosystem, which can be tested in the field.
Rolling on a smooth biparametric surface
Authors: Hégron Gérard 
Published: November 2006

AbstractIn this paper we present a method to calculate the rolling of a rigid convex object on a smooth biparametric surface where a single contact point is maintained during the animation. The object's motion is computed using a prediction‐correction schema. The prediction computes the motion of the object rolling on the tangent plane at the current contact point. The next contact point is obtained by projecting the predicted point onto the curved surface. A correction is made according to the local surface curvature. An algorithm which calculates the initial contact point between the surface and the object is given. The rolling of a ball is presented as an example.
Normal vector generation for sampled data using fourier filtering
Authors: Goss Michael E. , Page Ivor P. 
Published: November 2006

AbstractA three‐dimensional surface is a useful graphic representation of a two‐dimensional function which has been sampled on a regular grid. Shading the surface to simulate the effects of direct lighting makes visible small changes in the surface orientation, and enhances realism when the data represents a physical surface such as terrain. Shading interpolation calculations and surface patch generation techniques require the specification of a surface normal vector (or related slope information) at each sample point. These normal vectors are usually generated by averaging local data such as the normal vectors of the surfaces of a triangular mesh connecting the points. This paper describes a technique which uses Fourier filtering to generate normal vectors for two‐dimensional sampled data. Images and analysis of frequency spectra are included to show how this technique preserves detail which is lost using the averaging method. Performance figures show that this enhancement of detail in the final image can be achieved for only a small increase in computation time.
Sequential‐goal constraints for computer animation
Authors: Liu Wen‐Bang , Ko Ming‐Tat , Chang Ruei‐Chuan 
Published: November 2006

AbstractThe dynamic constraints technique has been proposed for building geometrical models composed of rigid bodies, which are made to act naturally, according to Newtonian laws, by specifying constraints on their states. In computer animation, the dynamic constraints technique alleviates the work‐load of animators who formerly had to plan animated sequences in detail by intuition alone. Nevertheless, for some real‐world applications, it is desirable to have a mechanism that makes physically‐based elements move according to a given scenario by providing some control states. The control states can be represented by transient constraints that are to be met and then released immediately. In this paper, a technique called the sequential‐goal constraints technique is proposed to provide such a mechanism. With the sequential‐goal constraints technique, it is easy to specify transient constraints according to a given scenario and derive proper forces and torques to drive an element to meet each transient constraint exactly at a specified time so that the whole motion of the element is continuous and integral.
Modelling and animation of generalized cylinders with variable radius offset space curves
Authors: Kim Myung‐Soo , Park Eun‐Joo , Lee Hwan‐Yong 
Published: November 2006

AbstractA method is presented for the modelling and animation of generalized cylinders with variable radius offset space curves. The boundary surface of a generalized cylinder is constructed: either as a translational sweep of cross‐sectional curves along the skeleton curve, or as a rotational sweep of profile curves around the skeleton curve. The cross‐sectional curves are computed as the variable radius offset curves of a circle in the normal plane, and the profile curves are computed as the variable radius offset space curves of the skeleton curve. The offset curves are approximated by spline curves, and the boundary surface of a generalized cylinder is approximated by the tensor product surface patches of the offset spline curves.
Collision response for deformable models based on hertz's contact theory
Authors: Terasawa Mikio , Kimura Fumihiko 
Published: November 2006

AbstractThis paper presents an animation technique of collision response for deformable models defined as a spring‐mass‐damper system. Our approach is to calculate impulsive forces to prevent penetration of colliding objects by means of Hertz's contact theory. With this theory, contact duration and deformation in collision are obtained according to physical properties such as mass and elasticity. Animators, therefore, can represent the differences between materials such as rubber and steel in the sequence of collision animations with a few intuitive physical parameters. We also describe a deformation mapping technique which reduces the computational time of dynamic analysis and realizes the effect of global deformation.
Animated human agents with motion planning capability for 3D‐space postural goals
Authors: Jung Moon‐Ryul , Badler Norman , Noma Tsukasa 
Published: November 2006

AbstractIn this paper, we present a rule‐based heuristic method of motion planning for an animated human agent with massively redundant degrees of freedom. It constructs motion plans to achieve 3D‐space goals of control points on the body, e.g. a hand, while avoiding collisions. Like the artificial potential field approach, the method performs motion decisions in 3D world space rather than in joint space. To handle the massively redundant degrees of freedom, we use a qualitative kinematic model, which specifies motions of body parts and dependencies among them, without specifying the exact distance parameters. This model helps the body select appropriate primitive motions for given goals of control points more globally than does the gradient vector of an artificial potential field of the body. The method simulates (in imagination) the suggested plan to find whether some body parts hit objects, and how much they penetrate the objects. Based on this simulated collision information, the method suggests intermediate goals of the collision body parts. A subplan to achieve these intermediate goals is again postulated by using the qualitative kinematic model. This explicit reasoning helps alleviate the basic cause of local minima in the potential field approach, namely, conflicts between attractive potential fields due to goal positions of control points and repulsive potential fields due to obstacles.
Automatic background music generation based on actors' mood and motions
Authors: Nakamura Jun‐Ichi , Kaku Tetsuya , Hyun Kyungsil , Noma Tsukasa , Yoshida Sho 
Published: November 2006

AbstractSince adding background music and sound effects even to short animations is not simple, an automatic music generation system would help improve the total quality of computer generated animations. This paper describes a prototype system which automatically generates background music and sound effects for existing animations. The inputs to the system are music parameters (mood types and musical motifs) and motion parameters for individual scenes of an animation. Music is generated for each scene. The key for a scene is determined by considering the mood type and its degree, and the key of the previous scene. The melody for a scene is generated from the given motifs and the chord progression for the scene which is determined according to appropriate rules. The harmony accompaniment for a scene is selected based on the mood type. The rhythm accompaniment for a scene is selected based on the mood type and tempo. The sound effects for motions are determined according to the characteristics and intensity of the motions. Both the background music and sound effects are generated so that the transitions between scenes are smooth.
Order‐controlled free‐form animation
Authors: Bechmann Dominique , Dubreuil Nicolas 
Published: November 2006

AbstractThis paper introduces an animation system directed by order. High‐level operations such as moving, turning, rolling and bouncing on a flat surface provide an easy‐to‐use interface to build animations. The underlying animation system relies on a constraint‐based deformation model.Previously, to build an animation the user had to break up the desired animation into a list of deformations composed of a set of constraints. In addition to each constraint, he had to control the size and the shape of the deformed area as well as the shape of the deformation. The goal of the order‐controlled animation is to encapsulate all the parameters of the deformations. Indeed, using these high‐level operations the underlying deformations are completely transparent to the user.Before introducing these operations, we will present some extensions of the deformation model such as the generalized shape of the deformed area and a rotating movement combined with the deformation. We also explain how to control velocity and acceleration.
Genetic programming for articulated figure motion
Authors: Gritz L. , Hahn J. K. 
Published: November 2006

AbstractWe present an approach to articulated figure motion in which motion tasks are defined in terms of goals and ratings. The agents are dynamically‐controlled robots whose behaviour is determined by robotic controller programs. The controller programs for the robots are evaluated at each time step to yield torque values which drive the dynamic simulation of the motion. We use the AI technique of genetic programming (GP) to automatically derive control programs for the agents which achieve the goals. This type of motion specification is an alternative to key framing which allows a highly automated, learning‐based approach to generation of motion. This method of motion control is very general (it can be applied to any type of motion), yet it allows for specifications of the types of specific motion which are desired for a high quality animation. We show that complex, specific, physically plausible and aesthetically appealing motion can be generated using these methods.
N‐body spacetime constraints
Authors: Tang Diane , Ngo J. Thomas , Marks Joe 
Published: November 2006

AbstractAnimators frequently choreograph complex motions for multiple objects that interact through collision and obstruction. In such situations, the use of physically based dynamics to confer visual realism creates challenging computational problems. Typically forward simulation is well understood, but the inverse problem of motion synthesis—that of synthesizing motions consistent both with physical law and with the animator's requirements—is generally tedious and sometimes intractable. We show how N‐body inverse problems can be formulated as optimization tasks. We present a simply stated, but combinatorially formidable example that exhibits all of the essential sources of complexity common to N‐body motion synthesis, and show how it can be solved approximately using heuristic methods based on evolutionary computation.
Visual simulation of water currents using a particle‐based behavioural model
Authors: Chiba Norishige , Sanakanishi Shinji , Yokoyama Kenichiro , Isao  , Ootawara  , Muraoka Kazunobu , Saito Nobuji 
Published: November 2006

AbstractSeveral CG researchers have simulated impressive ocean waves so far. Recently, other researchers have succeeded in simulating waterfalls by employing a mass of particles. However, visual simulation of water currents having complex surfaces, such as mountain streams and turbulent water, still remains a challenging problem thanks to their complicated patterns of behaviour. Effective simulation methods for water currents are expected to have abilities to represent the following remarkable behavioural visual features of water: the appearance of a pool, an obstacle avoidance flow, a fluent flow, a flow into an open space, the collision and the confluence of flows and the occurrence of splashes.In this paper, we present a new type of particle‐based simulation method for complex water currents which is not based on strict fluid dynamics but rather classified into a ‘quasi‐physically‐based’ simulation method constructed on the basis of algorithmic approaches. We first present a simple behavioural model of a ‘water‐particle’. Next, we propose a method for generating CG images of water currents from a set of water‐particles. Finally, we demonstrate the ability of our method by showing several examples of the simulation.
Modelling radiative properties of light sources and surfaces
Authors: Paul J. C. , Deville P. M. , Winkler C. 
Published: November 2006

AbstractThis paper describes methods that can be used for modelling radiative properties of light sources and materials, in a radiosity computation algorithm. These methods have been designed in order to improve the photo‐realistic rendering of complex architectural scenes as well as to allow illumination engineering applications. They are based on the accurate modelling of the spatial and spectral emittance distributions of the light sources, and the surface reflectance/transmittance distributions from measurement, and allow the exact colorimetric properties of the light sources and the surfaces to be calculated. A method for changing radiosity inputs during the radiosity process, without recalculating the solution entirely is also proposed. This allows modifications in design or dynamic lighting effects to be simulated more interactively.
Microwave assisted low temperature synthesis of MnZn ferrite nanoparticles
Authors: Zhenyu Lai , Guangliang Xu , Yalin Zheng 
Published: November 2006

Abstract
MnZnFe2O4ferrite nanoparticles were prepared by co-precipitation method using a microwave heating system at temperature of 100 °C. X-ray diffraction reveals the samples as prepared are pure ferrite nanocrystalline phase, transmission electron microscopy image analysis shows particles are in agglomeration state with an average size of about 10 nm, furthermore, crystal size of samples are increased with longer microwave heating.
Cloning and characterization of a cDNA encoding diacylglycerol acyltransferase from castor bean
Authors: He Xiaohua , Turner Charlotta , Chen Grace Q. , Lin Jiann‐Tsyh , McKeon Thomas A. 
Published: November 2006

AbstractThe oil from castor seed (Ricinus communis) contains 90% ricinoleate, a hydroxy FA that is used in producing numerous industrial products. Castor diacylglycerol acyltransferase (RcDGAT) is a critical enzyme, as it catalyzes the terminal step in castor oil biosynthesis in which the products contain two or three ricinoleoyl moieties. We have isolated a cDNA encoding RcDGAT from developing castor seeds. Analysis of the sequence reveals that this cDNA encodes a protein of 521 amino acids with a molecular mass of 59.9 kDa. Although there are regions of high similarity to other plant DGAT coding sequences, there are sequences that distinguish it as well. Southern blot analysis suggests that the castor genome contains a single copy of RcDGAT. Analysis by reverse transcription‐PCR reveals that the accumulation of the mRNA reaches its highest level at 19 d after pollination and declines thereafter. Expression of the full‐length cDNA for RcDGAT in the yeast Saccharomyces cerevisiae strain INVSc1 results in sevenfold higher DGAT activity compared with controls. When different molecular species of DAG were provided as substrates to the microsomal mixture, the RcDGAT showed a greater preference to catalyze the transfer of oleate from [14C]oleoyl‐CoA to diricinolein than to diolein and dipalmitolein. With the addition of 0.25 mM substrates, diricinolein gave 318 pmol/mg/min diricinoleoyloleoylglycerol (RRO), while diolein and dipalmitolein gave only about 195 pmol/mg/min of triolein (OOO) and 120 pmol/mg/min dipalmitoyleoylglycerol (PoPoO), respectively. This work will facilitate investigation of the role of RcDGAT in castor oil biosynthesis.
Effect of CLA on milk fat synthesis in dairy cows: Comparison of inhibition by methyl esters and free fatty acids, and relationships among studies
Authors: de Veth Michael J. , Griinari J. Mikko , Pfeiffer Angelika‐Maria , Bauman Dale E. 
Published: November 2006

AbstractCLA is a potent inhibitor of milk fat synthesis, as shown by investigations using mixtures of CLA isomers in FFA form. However, methyl esters of CLA can be initially formed in commercial synthesis, and their use in a supplement has certain manufacturing and cost advantages. Our objective was to compare abomasal infusion of methyl esters of CLA (ME‐CLA) and FFA of CLA (FFA‐CLA) on milk fat synthesis. Data were also combined with previous investigations to examine broader relationships between trans‐10,cis‐12 CLA and the reduction in milk fat. Three mid‐lactation, rumen‐fistulated Holstein cows were used in a 3×3 Latin square design. Treatments were (i) control, (ii) ME‐CLA, and (iii) FFA‐CLA. The ME‐CLA and FFA‐CLA treatments (4.2 g/d trans‐10,cis‐12 CLA) resulted in a comparable reduction in milk fat yield (38 and 39%, respectively) and pattern of reduction in individual FA. In contrast, milk yield, milk protein, and feed intake were unaltered by CLA treatment. Combining data across studies revealed strong correlations relating the reduction in milk fat yield to abomasal dose of trans‐10,cis‐12 CLA (R2=0.86), milk fat content of trans‐10,cis‐12 CLA (R2=0.93), and milk fat secretion of trans‐10,cis‐12 CLA (R2=0.82). Across studies, transfer efficiency of abomasally infused trans‐10,cis‐12 CLA into milk fat was relatively constant (22%; R2=0.94). Overall, ME‐CLA and FFA‐CLA were equally potent in reducing milk fat, and either form could be used to formulate a dietary supplement that would induce milk fat depression.