15030436
Scale-Space Derived From B-Splines
This paper proposes a scale-space theory based on B-spline kernels. Our aim is twofold: 1) present a general framework, and show how B-splines provide a flexible tool to design various scale-space representations. In particular, we focus on the design of continuous scale-space and dyadic scale-space frame representations. A general algorithm is presented for fast implementation of continuous scale-space at rational scales. In the dyadic case, efficient frame algorithms are derived using B-spline techniques to analyze the geometry of an image. The relationship between several scale-space approaches is explored. The behavior of edge models, the properties of completeness, causality, and other properties in such a scale-space representation are examined in the framework of B-splines. It is shown that, besides the good properties inherited from the Gaussian kernel, the B-spline derived scale-space exhibits many advantages for modeling visual mechanism including the efficiency, compactness, orientation feature and parallel structure.
9057651
Closed smooth piecewise bicubic surfaces
Two classes of closed piecewiee bicubic surfaces are considered. These surfaces are geometrically smooth about each extraordinary point and, for a large mesh and a large control polyhedron, they are parametrically smooth away from the extraordinary points. Furthermore, free parameters are available for manipulating the shape of the surface without changing the control polyhedron. The control is local for a large control polyhedron.
15089909
Image Metamorphosis with Scattered Feature Constraints
This paper describes an image metamorphosis technique to handle scattered feature constraints specified with points, polylines, and splines. Solutions to the following three problems are presented: feature specification, warp generation, and transition control. We demonstrate the use of snakes to reduce the burden of feature specification. Next, we propose the use of multilevel free-form deformations (MFFD) to compute C/sup 2/-continuous and one-to-one mapping functions among the specified features. The resulting technique, based on B-spline approximation, is simpler and faster than previous warp generation methods. Furthermore, it produces smooth image transformations without undesirable ripples and foldovers. Finally, we simplify the MFFD algorithm to derive transition functions to control geometry and color blending. Implementation details are furnished and comparisons among various metamorphosis techniques are presented.
27918831
Universality of mobility-gate field characteristics of electrons in the inversion charge layer and its application in MOSFET modeling
A mobility curve for electrons in a MOSFET inversion charge layer is determined from measured drain current of transistors produced by a wide range of MOS technologies. A comparison between this mobility curve and previously published results shows that a truly universal mobility curve does not exist and only local universal mobility curves can be expected, i.e. unique mobility curves which are valid over a finite range of MOS technologies and/or over a particular set of fabrication facilities. The curve's basic characteristic of being technology-independent over a wide range of process variation points out the potential of using such a local universal mobility curve as a powerful basis for developing predictive device modeling tools. This potential is demonstrated for an analytical MOSFET model and a two-dimensional device simulator where the mobility models have the general characteristics of experiment-based local universal mobility curves. >
14591532
Responsive Multimedia System for Virtual Storytelling
In this paper, we propose Responsive Multimedia System (RMS) for a virtual storytelling. It consists of three key components; Multi-modal Tangible User Interface (MTUI), a Unified Context-aware Application Model for Virtual Environments (vr-UCAM), and Virtual Environment Manager (VEManager). MTUI allows users to interact with virtual environments (VE) through human’s senses by exploiting tangible, haptic and vision-based interfaces. vr-UCAM decides reactions of VE according to multi-modal input. VEManager generates dynamic VE by applying the reactions and display it through 3D graphics and 3D sounds, etc. To demonstrate an effectiveness of the proposed system, we implemented a virtual storytelling system which unfolds a legend of Unju Temple. We believe the proposed system plays an important role in implementing various entertainment applications.
13363048
Statistical Shape Modelling of the Levator Ani with Thickness Variation
The levator ani is vulnerable to injury during childbirth and effective surgical intervention requires full knowledge of the morphology and mechanical properties of the muscle structure. The shape of the levator ani and regional thickening during different levels of physiological loading can provide an indication of pelvic floor dysfunction. This paper describes a coupled approach for shape and thickness statistical modelling based on harmonic embedding for volumetric analysis of the levator ani. With harmonic embedding, the dynamic information extracted by the statistical modelling captures shape and thickness variation of the levator ani across different subjects and during varying levels of stress. With this study, we demonstrate that the derived model is compact and physiologically meaningful, demonstrating the practical value of the technique.
1670024
Scattered Data Interpolation with Multilevel B-Splines
The paper describes a fast algorithm for scattered data interpolation and approximation. Multilevel B-splines are introduced to compute a C/sup 2/ continuous surface through a set of irregularly spaced points. The algorithm makes use of a coarse to fine hierarchy of control lattices to generate a sequence of bicubic B-spline functions whose sum approaches the desired interpolation function. Large performance gains are realized by using B-spline refinement to reduce the sum of these functions into one equivalent B-spline function. Experimental results demonstrate that high fidelity reconstruction is possible from a selected set of sparse and irregular samples.