waashk/acm huggingface dataset:
sticky splines: definition and manipulation of spline structures with maintained topological relations  this paper describes an augmentation to the spline concept to account for topological relations between different spline curves. these topological relations include incidence relations, constraining the extremes of spline curves to other spline curves, and also more general geometric relations, for example, involving the tangents of spline curves in their extremes. to maintain these incidence relations, some spline curves may have to be transformed (translated, rotated, scaled), or even deformed (i.e., the shape of the curve may change) as a result of modifying other spline curves. a data structure and algorithms are given to implement the propagation of these transformations and deformations.  based on the augmented spline concept, to be called sticky splines, both a script system to represent spline structures and an interactive system for editing drawings while automatically, maintaining their topological structure are presented.  c. w. a. m. van overveld marie luce viaud
variance based classifier comparison in text catergorization (poster session)  text categorization is one of the key functions for utilizing vast amount of documents. it can be seen as a classification problem, which has been studied in pattern recognition and machine learning fields for a long time and several classification methods have been developed such as statistical classification, decision tree, support vector machines and so on. many researchers applied those classification methods to text categorization and reported their performance (e.g., decision tree[3], bayes classifier[2], support vector machine[l]). yang conducted comprehensive study of comparison or text categorization and reported that k nearest neighbor and support vector machines works well for text categorization[4].  in the previous studies, classification methods were usually compared using single pair of training and test data however, classification method with more complex family of classifiers requires more training data and small training data may result in deriving unreliable classifier, that is, the performance of the derived classifier varies much depending on training data. therefore, we need to take the size of training data into account when comparing and selecting a classification method. in this paper, we discuss how to select a classifier from those derived by various classification methods and how the size of training data affects the performance of the derived classifier.  in order to evaluate the reliability of classification method, we consider the variance of accuracy of derived classifier. we first construct a statistical model. in the text categorization, each document is usually represented with a feature vector that consists of weighted frequencies of terms. in the vector space model, document is a point in high dimensional feature space and a classifier separates the feature space into subspaces each of which is labeled with a category.  atsuhiro takasu kenro aihara
imt-rb/ed: a system based on multi-reorganization (abstract)  with the advance of ai and the coming of the idea of intelligent mt system, several important practical and theoretical advances have been made in the field of machine translation. recently a system called imtrb/ec is being implemented in our institute. it is the grammar rule based system of imt/ec (intelligent english-chinese translation system) and is a relatively independent and complete subsystem. as a rule based system, many ai techniques have been used in it.  this paper presents a method for the multi- reorganization of the rule base system and the general principles of imt- rb/ec. this system is composed by six parts: rule base, parsing mechanism, rule accessing mechanism and man- machine interfaces. a transformation rule is composed by five parts: source expression, target expression, condition, context change and chinese translation. the knowledge and the algorithms are separated, the rules are divided into layers. we make the system as subset of grammar rules, the learning mechanism can add new rules or delete unsatisfied rules or change a rule according to the running result or the knowledge of expert. with different attributes (dynamic or quiescent factors), we realized the multi- reorganization. the result of multi-reorganization will be used as the heuristic information. the performance of the system is greatly improved by apply these techniques.  ye yiming chen zhao-xiong zhang xiong gao qinshi
in-house vs. off-the-shelf graphic software tools in this article, we discuss the software tools that rhythm & hues uses to create such award-winning effects as those featured in _babe,_ the coca-cola polar bears commercials and ride films such as _seafari._ the primary topic for discussion is the question of internal "in-house" proprietary software versus external "off-the-shelf" commercial software, as relates to our company.to help explain what we are doing today, we will look at the environment when rhythm & hues was founded, how the industry has changed and the challenges we face today. since this is a complex subject, there are varying opinions about the analysis of the situation within the company, so the description below should not be viewed as fact, but as a presentation of the authors' views. linda martino paul allen newell
application of modern software techniques to modeling and simulation  it is commonly agreed that software developments tend to be high risk activities; simulation is recognized as being even more "exciting". great emphasis is being placed to develop methodologies which lower the risk of software development. since a major portion of simulation activity is software oriented, it is natural to look to these modern software methodologies for solutions applicable to the modeling and simulation community. the total solution to current dilemmas is many years away. however, significant progress is being made to develop a comprehensive software development methodology that is readily extendable to simulation activities. the major additional burden of modeling and simulation is the handling of the system modeling part of the process. this paper introduces an integrated software methodology (isomet) currently in use which has been successfully applied to simulation projects. modifications to the methodology to accommodate specialized modeling considerations are discussed.  ronald m. huhn edward r. comer
low cost illumination computation using an approximation of light wavefronts  we present an efficient method to simulate the propagation of wavefronts and approximate the behavior of light in an environment of freeform surfaces. the proposed method can emulate the behavior of a wavefront emanating from a point or spherical light source, and possibly refracted and/or reflected from a freeform surface. moreover, it allows one to consider and to render images with extreme illumination conditions such as caustics.  the proposed method can be embedded into rendering schemes that are based on scan conversion. using a direct freedom surface z buffer renderer, we also demonstrate the use of the wavefront approximation in illumination computation.  gershon elber
massively parallel and distributed simulation of a class of discrete event systems: a different perspective  in this paper we propose a new approach to parallel and distributed simulation of discrete event systems. most parallel and distributed discrete event simulation algorithms are concerned with the simulation of one "large" discrete event system. in this case the computational intensity is due to the size and complexity of the simulated system. in contrast, we are interested in simulating a "large" number of "medium sized" systems. these are variants of a "nominal system" with different system parameter values or operation policies. the computational intensity in our case is due to the "large" number of simulated variants. many simulation projects such as factor screening, performance modeling, and optimization require system performance evaluations at many parameter values; and others, we believe, could significantly benefit from them.  there is considerable work in the literature on stochastic coupling of trajectories of parametric families of stochastic processes. our approach can be viewed as the simulation of the coupled trajectories. we use a single clock mechanism that drives all trajectories simultaneously, hence the approach is called single clock multiple system (scms) simulation. the single clock synchronizes all trajectories such that the "same" event occurs at the "same" time at all systems. this synchronization is the basis of our parallel and distributed algorithms.  we focus on a particular implementation of the scms simulation using the so- called standard clock (sc) technique and also on the massively parallel implementation of the sc algorithms on the simd connection machine. orders of magnitude of speedup is possible. furthermore, the possibility of concurrent performance evaluation and comparison at many system parameter values offers new and significant opportunities for performance optimization.  pirooz vakili
from contours to surfaces: testbed and initial results  this paper is concerned with the problem of reconstructing the surface of three-dimensional objects, given a collection of planar contours representing cross-sections through the objects. this is an important problem, with applications in clinical medicine, bio-medical research and instruction, and industrial inspection. current solutions to this problem have raised interesting theoretical questions about search techniques and the exploitation of domain- specific aspects of such search problems. in this paper, we survey known reconstruction techniques, describe a testbed for evaluating these techniques and present an improvement on the simple divide-and-conquer method analyzed by fuchs, kedem and uselton [5].  kenneth r. sloan james painter
constructive modeling of frep solids using spline volumes  we present an approach to constructive modeling of frep solids [2] defined by real-valued functions using 4d uniform rational cubic bspline volumes as primitives. while the first three coordinates are used to represent the spatial component of the volume to be sculpted, the fourth coordinate is used as a scalar, which corresponds to a function value or a volume density. thus, the shape can be manipulated by changing the scalar control coefficients of the spline volume. this modeling process is interactive as the isosurface can be polygonized and visualized in real time. the distance property we obtain, combined with the properties of the spline volumes, allow us to use the resulting 3d solid as a leaf of a constructive tree and to apply to it set- theoretic, blending and other operations defined using r-functions [2]. additional deformations can be achieved by moving arbitrary points in the coordinate space and applying space mapping at any level of the constructive tree. the final constructive solid is defined by a single real-valued function evaluated by the tree traversing procedure.  schmitt benjamin pasko alexander schlick christophe
simulation of natural scenes using textured quadric surfaces  because of the high complexity of the real world, realisticsimulation of natural scenes is very costly in computation. thetopographical subtlety of common natural features such as trees andclouds remains a stumbling block to cost- effective computermodeling. a new scene model, composed of quadric surfaces boundedwith planes and overlaid with texturing, provides an efficient andeffective means of representing a wide range, of natural features.the new model provides a compact and functional data base whichminimizes the number of scene elements. efficient hidden surfacealgorithms for quadric surfaces bounded by planes are included. amathematical texturing function represents natural surface detailin a statistical manner. techniques have been developed to simulatenatural scenes with the artistic efficiency of an impressionistpainter.  geoffrey y. gardner
seamless texture mapping of subdivision surfaces by model pelting and texture blending  subdivision surfaces solve numerous problems related to the geometry of character and animation models. however, unlike on parametrised surfaces there is no natural choice of texture coordinates on subdivision surfaces. existing algorithms for generating texture coordinates on non- parametrised surfaces often find solutions that are locally acceptable but globally are unsuitable for use by artists wishing to paint textures. in addition, for topological reasons there is not necessarily any choice of assignment of texture coordinates to control points that can satisfactorily be interpolated over the entire surface. we introduce a technique, pelting, for finding both optimal and intuitive texture mapping over almost all of an entire subdivision surface and then show how to combine multiple texture mappings together to produce a seamless result.  dan piponi george borshukov
computer typesetting at a university  as text processing becomes more widespread at a university, users become intrigued with the possibilities of making publishing easier, quicker, and less costly. authors, administrative offices, editors of newsletters, and even students creating attractive resumes want to use computerized typesetting. not all universities can justify buying their own typesetting equipment, but files can be created on a university computer and sent to a commercial typesetter for processing. such a system will be discussed.  hannah kaufman
continuous anti-aliased rotation and zoom of raster images  raster graphics images are difficult to smoothly rotate and zoom because of geometric digitization error. a new algorithm is presented for continuous rotation and zoom, free from the disturbing aliasing artifacts introduced by traditional methods. applications include smooth animation. no matrix multiplication of pixel coordinates is executed. instead row and column parallel operations which resemble local digital filters are used. this suggests real time implementation with simple hardware. anti-aliasing is inherent in the algorithm which operates solely on pixel data, not the underlying geometric structures whose images the pixels may depict. zoom magnification is achieved without replicating pixels and is easily attained for any rational scale factor including but not restricted to the integer values which most existing commercial raster graphics systems use.  the algorithm is based on a digitized code for lines on rasters, generalized to an interpolation scheme capable of executing all linear geometric transformations. samples of images which have been rotated and zoomed by a software implementation of the algorithm are presented.  carl f. r. weiman
rendering on a budget: a framework for time-critical rendering  we present a technique for optimizing the rendering of highdepth complexity scenes. prioritized-layered projection (plp) does this by rendering an estimation of the visible set for each frame. the novelty in our work lies in the fact that we do not explicitly compute visible sets. instead, our work is based on computing on demand a priority order for the polygons that maximizes the likelihood of rendering visible polygons before occluded ones for any given scene. given a fixed budget, e.g. time or number of triangles, our rendering algorithm makes sure to render geometry respecting the computed priority.  there are two main steps to our technique: (1) an occupancy-based tessellation of space; and (2) a solidity-based traversal algorithm. plp works by computing an occupancy-based tessellation of space, which tends to have smaller cells where there are more geometric primitives, e.g., polygons. in this spatial tessellation, each cell is assigned a solidity value, which is directly proportional to its likelihood of occluding other cells. in its simplest form, a cell's solidity value is directly proportional to the number of polygons contained within it. during our traversal algorithm, cells are marked for projection, and the geometric primitives contained within them actually rendered. the traversal algorithm makes use of the cells' solidity, and other view-dependent information to determine the ordering in which to project cells. by tailoring the traversal algorithm to the occupancy-based tessellation, we can achieve very good frame rates with low preprocessing and rendering costs.  in this paper, we describe our technique and its implementation in detail. we also provide experimental evidence of its performance and briefly discuss extensions of our algorithm.  james t. klosowski cláudio t. silva
anti-aliasing through the use of coordinate transformations  the use of the point-line distance in evaluating the 2-dimensional anti- aliasing convolution is studied. we derive transformations of the point-spread function (psf) that give the effective convolution in terms of the point-line distance when the class of object space primitives is limited to lines and polygons. because the quality of filtering is embedded in a table indexed by the point- line distance, this approach allows one to use arbitrarily complex psf's, only the width and not the shape of the psf affects the amount of computation. we apply the cordic algorithm to point-line distance evaluation, and show its merits. also, we show the more standard use of the cordic algorithm for coordinate rotation, polar-to-rectangular and rectangular-to- polar conversion, and calculating the norm of a vector. rounded end points can be achieved by using the point-segment distance, computational methods are given, including cordic implementation. the cordic algorithms for the aforementioned geometric operations are prime candidates for vlsi implementation because of their inherent parallel/pipeline nature.  kenneth turkowski
an extended transformation approach to inductive logic programming inductive logic programming (ilp) is concerned with learning relational descriptions that typically have the form of logic programs. in a transformation approach, an ilp task is transformed into an equivalent learning task in a different representation formalism. propositionalization is a particular transformation method, in which the ilp task is compiled to an attribute-value learning task. the main restriction of propositionalization methods such as linus is that they are unable to deal with nondeterminate local variables in the body of hypothesis clauses. in this paper we show how this limitation can be overcome, by systematic first-order feature construction using a particular individual- centered feature bias. the approach can be applied in any domain where there is a clear notion of individual. we also show how to improve upon exhaustive first-order feature construction by using a relevancy filter. the proposed approach is illustrated on the "trains" and "mutagenesis" ilp domains. nada lavrac peter a. flach
recognizing objects in range images and finding their position in space  we present a method for recognizing polyhedral objects from range images. an object is said to be recognized as one of the models of a library of object models when many features of the model can be made to match the features of the observed object by the same rotation-translation transformation (the object pose). in the proposed approach, the number of considered pairs of image and model features is reduced by selecting at random only a few of all the possible image features and matching them to appropriate model features. the rotation and translation required for each match are computed, and a robust lms (least median of squares) method is applied to determine clusters in translation and rotation spaces. the validity of the object pose suggested by the clusters is verified by a similarity measure which evaluates how well a model in the suggested pose would fit the original range image. the pose estimation and verification are performed for all models in the model library. the recognized model is the model which yields the smallest value of the similarity measure, and the pose of the object is found in the process.  jun ohya daniel dementhon larry s. davis
dart: expert systems for automated computer fault diagnosis  in anticipation of computer faults, most manufacturers prepare specialized diagnostic aids that allow field engineers without complete knowledge of a system to diagnose the majority of its failures. unfortunately, these diagnostics are not infallible for they do not take into account every fault and combination of faults for every possible system configuration. thus, in some cases, it is necessary to call in someone with expert knowledge about the design of the system. these experts are expensive and often not immediately available, and there is inevitably a delay and a loss of working time to the system users.  dart is a joint project of the heuristic programming project and ibm that explores the application of artificial intelligence techniques to the diagnosis of computer faults. the primary goal of the dart project is to develop programs that capture the special design knowledge and diagnostic abilities of these experts and to make them available to field engineers. the practical goal is the construction of an automated diagnostician capable of pinpointing the functional units responsible for observed malfunctions in arbitrary system configurations.  michael genesereth james s. bennett clifford r. hollander
texture synthesis over arbitrary manifold surfaces  algorithms exist for synthesizing a wide variety of textures over rectangular domains. however, it remains difficult to synthesize general textures over arbitrary manifold surfaces. in this paper, we present a solution to this problem for surfaces defined by dense polygon meshes. our solution extends wei and levoy's texture synthesis method [25] by generalizing their definition of search neighborhoods. for each mesh vertex, we establish a local parameterization surrounding the vertex, use this parameterization to create a small rectangular neighborhood with the vertex at its center, and search a sample texture for similar neighborhoods. our algorithm requires as input only a sample texture and a target model. notably, it does not require specification of a global tangent vector field; it computes one as it goes - either randomly or via a relaxation process. despite this, the synthesized texture contains no discontinuities, exhibits low distortion, and is perceived to be similar to the sample texture. we demonstrate that our solution is robust and is applicable to a wide range of textures.  li-yi wei marc levoy
accelerating 3d convolution using graphics hardware (case study)  many volume filtering operations used for image enhancement, data processing or feature detection can be written in terms of three-dimensional convolutions. it is not possible to yield interactive frame rates on todays hardware when applying such convolutions on volume data using software filter routines. as modern graphics workstations have the ability to render two- dimensional convoluted images to the frame buffer, this feature can be used to accelerate the process significantly. this way generic 3d convolution can be added as a powerful tool in interactive volume visualization toolkits.  matthias hopf thomas ertl
the system dynamics approach to analysis of complex industrial and management systems  the tutorial is designed to expand a person's ability to understand and to model complex industrial and management systems. modeling of physical systems such as aircraft flight or engineering design structures are not addressed. the system dynamics approach to examining, conceptualizing, and modeling complex systems is emphasized. complex managerial and social systems are of special interest. the informational feedback characteristics of these systems are discussed and methods to focus on feedback structures are presented. special attention is given to the dynamic interaction among structure, policy, and time delays in decision and actions that determine system behavior and performance.  thomas d. clark