ppxscal/embedding_network huggingface dataset:
Parallel Progressive Radiosity with Adaptive Meshing
Authors: Yizhou Yu, Oscar H. Ibarra, Tao Yang
Venue:  (1996)

Progressive radiosity is widely used for realistic image synthesis in computer graphics applications. High-quality image generation usually requires radiosity with adaptive patch refinement to account for global illumination effects from irregular objects in a 3D space. Parallelizing such an algorithm with adaptive refinement is difficult since computation cost for each object varies from one iteration to another depending on the location of dynamically selected shooting patches. Dynamic load balancing is required but its overhead is high for distributed memory systems. This paper presents an efficient parallel algorithm for progressive radiosity, which adopts a static processor assignment strategy to take advantages of hierarchical computation structure in this problem, minimize communication and balance dynamic load. Our experiments on a Meiko CS-2 distributed memory machine show that this algorithm has achieved good performance for the tested cases.
Classes of Numeration Models of $\lambda$-Calculus
Authors: K, Akira a
Venue:  (1984)

In [4] the reflexive structures in the category of numeration were studied. It was shown that every numerated reflexive set forms a ``numeration model of $\lambda$-calculus''''. In this short note we formalize the concept of numeration models of $\lambda$-calculus, and study several interesting subclasses. Even though the class of numeration models does not coincide with the class of numerated reflexive sets, we can show that the class of numeration models with ``$\lambda$-definability'''' property is equivalent to the class of numerated reflexive sets with ``$\lambda$-representability'''' property. Through this we observe relation between $\lambda$-definability and acceptability of numerations discussed in [5].
Measurement of Software Maintainability and Reusability in the Object Oriented Paradigm
Authors: Sallie M. Henry, Mark Lattanzi
Venue:  (1994)

The Metrics Group of Virginia Tech has been studying the object oriented paradigm and how it relates to software maintenance and software reusability in an attempt to make programmers more productive. Software reuse is the key to increased productivity within the software development process. By reusing existing software, time and effort are saved in the testing and maintenance phases of a software product. The object oriented paradigm is designed to enhance software reusability through encapsulation and inheritance (CoxB86, Meye87). This paper describes the results of three studies on object oriented metrics and also a reusability study currently in progress. The first study investigates the maintainability of object oriented software versus procedural software. The second one examines the relationship between programmer productivity, software reuse, and the object oriented paradigm. The third study proposes and validates a new suite of object oriented metrics based on the MOOSE metrics developed by Chidamber and Kemerer (Chid91). These new metrics are shown to predict maintainability from object oriented designs and source code.
SPECTRAL K-WAY RATIO-CUT PARTITIONING -- PART I: PRELIMINARY RESULTS
Authors: Pak K. Chan, Martine Schlag, Jason Zien
Venue:  (1992)

Recent research on partitioning has focussed on the ratio-cut cost metric which maintains a balance between the sizes of the edges cut and the sizes of the partitions without fixing the size of the partitions a priori. Iterative approaches and spectral approaches to two-way ratio-cut partitioning have yielded higher quality partitioning results. In this paper we develop a spectral approach to multi-way ratio-cut partitioning which provides a generalization of the ratio-cut cost metric to k-way partitioning and a lower bound on this cost metric. Our approach uses Lanczos algorithm to find the k smallest eigenvalue/eigenvector pairs of the Laplacian of the graph. The eigenvectors are used to construct an orthogonal projection to map a vertex (of the graph) in an n-dimensional space into a k-dimensional subspace. We exploit the (near) orthogonality of the projected points to effect high quality clustering of points in a k-dimensional subspace. An efficient algorithm is presented for coercing the points in the k-dimensional subspace into k-partitions. Advancement over the current work is evidenced by the results of experiments on the standard MCNC benchmarks.
From Play-In Scenarios to Code: An Achievable Dream
Authors: D. Harel
Venue:  (2000)

A complete development scheme for complex reactive systems is discussed, supported by semantically rigorous automated tools, within which one can go from a high-level, user-friendly requirement capture method, which we call play-in scenarios, via the rich sequence language of LSCs, to full behavioral descriptions of the system parts, and from there to a final implementation. A cyclic process consisting of verification against requirements and synthesis from requirements plays an important part in the scheme, which is not quite as imaginary as it may sound. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Efficient Computing of Least Fixpoints
Authors: Krzysztof R. Apt
Venue:  (1988)

We systematically derive efficient algorithms for computing the least fixpoints of monotonic operators in the context of deductive databases. To this purpose we identify additivity as a key property assumed from the operator and study additive operators on complete lattices. To handle the general case certain combinations of additive operators need to be considered.
Regional flood frequency analysis using L-moments
Authors: G. Onusluel, S. D. Ozkul, N. B. Harmancioglu
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

In the study presented, regional flood frequency analysis is carried out for three western river basins in Turkey. The method of L-moments is employed for this purpose, using a four-step procedure, i.e., screening of data, identification of homogenous regions, selection of a regional distribution, and estimation of the regional frequency distribution. A reliable regional curve is sought for three basins by evaluating the discordance measure, heterogeneity measure, and the goodness-of-fit measure.
Temporal Aspects of Tasks in the User Action Notation
Authors: H. R Hartson, Philip D. Gray
Venue:  (1991)

The need for communication among a multiplicity of cooperating roles in user interface development translates into the need for a common set of interface design representation techniques. The important difference between design of the interaction part of the interface and design of the interface software calls for representation techniques with a behavioral view---a view that focuses on user interaction rather than on the software. The User Action Notation (UAN) is a user- and task-oriented notation that describes physical (and other) behavior of the user and interface as they perform a task together. The primary abstraction of the UAN is a user task. The work reported here addresses the need to identify temporal relationships within user task descriptions and to express explicitly and precisely how designers view temporal relationships among those tasks. Drawing on simple temporal concepts such as events in time and preceding and overlapping of time intervals, we identify basic temporal relationships among tasks: sequence, waiting, repeated disjunction, order independence, interruptibility, one-way interleavability, mutual interleavability, and concurrency. The UAN temporal relations, through the notion of modal logic, offer an explicit and precise representation of the specific kinds of temporal behavior that can occur in asynchronous user interaction, without the need to detail all cases that might result.
Hybrid Bases in Graphs
Authors: L. A. Novak, A. M. Gibbons
Venue:  (1992)

In this paper we introduce a new concept, that of hybrid base, which is a maximal circuitless and cutsetless subset of a graph. Although this concept of simultaneous circuitlessness and cutsetlessness has been used in proofs of some theorems in so called hybrid graph theory, it has not received much attention. Only largest circuitless and cutsetless subsets (hybrid bases of maximum cardinality) have been recognised as important and then only as an auxiliary notion. In contrast to maximally circuitless subsets (trees) or to maximally cutsetless subsets (cotrees), hybrid bases are not of the same cardinality. This fact, although seemingly an "imperfection is the cause of rich structure which we describe in this paper through several propositions. The concept of hybrid bases is related to several important notions in hybrid orientated graph theory. For example, it is related to maximally distant pairs of trees, to complementary pairs of trees, to perfect trees and to topological degree of freedom. It is also closely related to the problem of finding the minimum number of independent variables in the hybrid analysis of electrical networks.
AN APPROACH TO THE DECOMPOSITION OF LARGE STOCHASTIC MODELS
Authors: Alexandre Brandwajn
Venue:  (1993)

A large family of decomposition methods largely used in the solution of queueing models divides the queueing model into smaller subsystems. The latter must be solved for all values of the state description retained for the aggregate model which represents the interactions among the subsystems. For a larger queueing system, even with relatively simple decomposed subsystems, this may represent a significant computational effort. The goal of our approach is to avoid the evaluation of the subnetworks for all values of the state description vector. Instead, we propose to track the probability distribution for the aggregate state description, and to evaluate the subnetwork in the regions where this probability exhibits a local maximum. In other regions, we propose to evaluate the subnetwork at only a few points. Outside the evaluation points, we use a simple curve fitting to generate the missing points. (available by papercopy only)
AN ANALYSIS OF SHORTS IN CMOS STANDARD CELL CIRCUITS
Authors: Alvin Jee, F. J Ferguson
Venue:  (1994)

In order to provide high levels of IC quality, we must be able to detect the presence of a very high percentage of the defects that may occur in circuits. Our long term goal is to address this problem by developing guidelines to design circuits to be more easily tested without requiring complex fault models or testing techniques. This paper is a first step towards this goal. This paper contains data on which shorting defects are most likely to occur in CMOS standard cell circuits and which are most likely to not be detected by standard testing methods.
Learning to Grasp Using Visual Information
Authors: I. Kamon, T. Flash, S. Edelman
Venue:  (1994)

A scheme for learning to grasp objects using visual information is presented. A system is considered that coordinates a parallel-jaw gripper (hand) and a camera (eye). Given an object, and considering its geometry, the system chooses grasping points, and performs the grasp. The system learns while performing grasping trials. For each grasp we store location parameters that code the locations of the grasping points, quality parameters that are relevant features for the assessment of grasp quality, and the grade. We learn two separate subproblems: (1) to choose the grasping points, and (2) to predict the quality of a given grasp. The location parameters are used to locate grasping points on new target objects. We consider a function from the quality parameters to the grade, learn the function from examples, and later use it to estimate grasp quality. In this way grasp quality for novel situations can be generalized and estimated.
A design methodology for NOC-based systems
Authors: Juha-Pekka Soininen, Hannu Heusala
Venue: Networks on chip (2003)

Diversity of computational requirements of information technology products will increase. The products will be based on computers, but the full exploitation of silicon capacity will require improvements in design productivity and system architectures. The chapter presents a backbone-platform-system methodology for development of products that are based on a network-on-chip concept. Encapsulation of dedicated subsystems into a NOC system is the key idea of an "integrated distributed embedded system" approach. The cornerstones of the methodology are the reuse of a NOC backbone and a platform architecture. The NOC backbone encapsulates the physical integration problems into communication solution for system architect. The NOC platform provides application area optimized computation and storage resources for system developers. Essential parts of the methodology are decision-support methods for both NOC platform and NOC system designers.
Determining Stopping Criteria in the Generation of Web-Derived Langua ge Models
Authors: Gary A. Monroe, David R. Mikesell, James C. French
Venue:  (2000)

In this work, we present a small-scale evaluation of two query-based sampling techniques for building language models, using a database comprised of world-wide web documents. We propose a metric by which it is possible to determine when to cease sampling a given web database, and we compare this new metric to other metrics that have been used in previous work to determine the fidelity of sampled language models.
Distance Labeling Schemes for Well-Separated Graph Classes
Authors: M. Katz, N. A. Katz, D. Peleg
Venue:  (1999)

Distance labeling schemes are schemes that label the vertices of a graph with short labels in such a way that the distance between any two vertices can be inferred from inspecting their labels. It is shown in this paper that the classes of interval graphs and permutation graphs enjoy such a distance labeling scheme using O(log2 n) bit labels on n-vertex graphs. Towards establishing these results, we present a general property for graphs, called well-(a,g)-separation, and show that graph classes satisfying this property have O(g(n)?logn) bit labeling schemes. In particular, interval graphs are well-(2,logn)-separated and permutation graphs are well-(6,logn)-separated.
ON THE MEASURED EQUATION OF INVARIANCE
Authors: Weikai Sun, Wei Hong, Wayne W. Dai
Venue:  (1997)

The key to the method of measured equation of invariance (MEI) is the postulate: "the MEI is invariant to the excitation". In this paper, we proved that the MEI is independent of the excitation with the error bounded by O(h^2), where h is the discretization step. We also proved that the consistent condition || L phi - M phi /h^2 || = e, where L is the partial differential operator, and M the equivalent MEI operator. If the MEI coefficients C^*_i (i=1,...,4) are determined from the special distribution named metrons on the boundary of the object, then e = d J(s), otherwise e = J(s), where J(s) is a functional of the source distribution s, and d J(s) is the perturbation of the functional J(s). And finally we pointed out that the error between the accurate solution and the solution of ME I is bounded by two terms, one is caused by the FD approximation at interior nodes which is proportional to h^2, another is caused by MEI and is independent of h but proportional to d J(s) which ensured the accuracy of MEI solution.
A Comparison of the LBG, LVQ, MLP, SOM and GMM Algorithms for Vector Quantisation and CLustering Analysis
Authors: Roberto Togneri, D. Farrokhi, Yaxin Zhang, Yianni Attikiouzel
Venue:  (1992)

We compare the performance of five algorithms for vector quantisation and clustering analysis: the Self-Organising Map (SOM) and Learning Vector Quantization (LVQ) algorithms of Kohonen, the Linde-Buzo-Gray (LBG) algorithm, the MultiLayer Perceptron (MLP) and the GMM/EM algorithm for Gaussian Mixture Models (GMM). We propose that the GMM/EM provides a better representation of the speech space and demonstrate this by comparing the GMM with the LBG, LVQ, MLP and SOM algorithms in phoneme classificationand digit recognition.
Finding Structure in the Vowel Space
Authors: Mylene Pijpers, Mike Alder, Roberto Togneri
Venue:  (1993)

From the TIMIT database labelled speech waveform segments from 33 speakers were extracted. There were 8 categories of speech data, each representing a vowel sound. In each category were 80 - 130 utterances. The waveform segments were processed by taking a FFT, on 32 msec frames and binning the result into 12 frequency bands. This way each frame will be represented by 12 numbers/values. They become points in R12 and each utterance is a short trajectory in R12. The 8 vowel categories become 8 clusters of such trajectories. By projecting the clusters onto the screen of a SUN workstation, it was observed that each vowel cluster appeared to be substantially gaussian. The covariance matrix and the centers were computed. Dimension estimates of each vowel by Principal Components Analysis show that the eight clusters lie close to a plane in the filterbankspace, and that the principal axes of the vowel clusters make a small and consistent angle with respect to this plane. This confirms the results of Plomp, e.a. [4] who found the vowel space to be essentially 2 dimensional. Projecting the centroids of the vowel clusters onto this plane gives a representation of the vowels which is very similar to the configuration we get when plotting the first and second formant, F1 and F2, of the vowels and the front-back and high-low diagram of vowels used in phonetics. This method may determine the vowel class more reliably than Formant tracking procedures.
Variable-Complexity Response Surface Approximations for Wing Structural Weight in HSCT Design
Authors: Matthew Kaufman, Vladimir Balabanov, Susan L. Burgee, Anthony A. Giunta, Bernard Grossman, Raphael T. Haftka, William H. Mason, Layne T. Watson
Venue:  (1996)

A procedure for generating and using a polynomial approximation to wing bending material weight of a High Speed Civil Transport (HSCT) is presented. Response surface methodology is used to fit a quadratic polynomial to data gathered from a series of structural optimizations. Several techniques are employed in order to minimize the number of required structural optimizations and to maintain accuracy. First, another weight function based on statistical data is used to identify a suitable model function for the response surface. In a similar manner, geometric and loading parameters that are likely to appear in the response surface model are also identified. Next, simple analysis techniques are used to find regions of the design space where reasonable HCST designs could occur. The use of intervening variables along with analysis of variance reduce the number of polynomial terms in the response surface model function. Structural optimization is then performed by the program GENESIS on a 28-node Intel Paragon. Finally, optimizations of the HSCT are completed both with and without the response surface.
Preliminary Validation of a Lightweight Approach to Consistency ofScenarios and Class Models
Authors: Martin Glinz, Nancy Schett
Venue:  (2000)

In this paper, we describe a preliminary experimental validation of our approach to consistency between a scenario model and a class model that is based on minimizing overlap between the models and on systematic crossreferencing. The results clearly indicate that the participants in the experiment preferred our lightweight approach to a classical approach.
Discrete Event Simulation With Pascal
Authors: Robert M. O''Keefe, Ruth M. Davis
Venue:  (1986)

Pascal_SIM is a collection of Pascal constants, types, variables, functions and procedures for developing event, activity, three-phase of process oriented discrete-event simulation models. Facilities are provided for queue processing, time advance and event list maintenance, control of entities and resources, random number generation and streams, sampling from parametric and empirical distributions, statistics collection, and visual displays.
PSE Research at Virginia Tech: An Overview
Authors: Abrams Marc, Allison Donald, Kafura Dennis, Ribbens Calvin, Rosson Mary Beth, Shaffer Clifford, Watson Layne T.
Venue:  (1998)

The purpose of this report is to give an overview of the activities of the research group in problem solving environments (PSEs) at Virginia Tech. Most of the report is devoted to an introduction to the area itself, with particular emphasis on our perspective and goals. After a brief attempt at defining the term PSE, we consider individually the three key words: problem: what problem domains are we addressing? solving: what characterizes the solution process? environment: what should the computational environment include? The final section summarize our current specific interests. For more information about PSE research at Virginia Tech, please visit our home page at www.cs.vt.edu/~pse.
Tight Size Bounds for Packet Headers in Narrow Meshes
Authors: Micah Adler, Faith Fitch, Leslie A Goldberg, Mike Paterson
Venue:  (2000)

Consider the problem of sending a single message from a sender to a receiver through an m x n mesh with asynchronous links that may stop working, and memoryless intermediate nodes. We prove that for m = O(1), it is necessary and sufficient to use packet headers that are Theta(log log n) bits long.
Syntactic Pattern Recognition of Simple Shapes
Authors: Robert A. McLaughlin, Mike Alder
Venue:  (1993)

A method is described to recognise hand-drawn cubes. The problem is treated hierachically and broken into several sub-problems. Each sub-problem is solved using essentially the same technique. This is an early version of the work detailed in Recognizing Cubes in Images.
Genetic Algorithms and the O(n ln n) Complexity on Selected TestFunctions
Authors: Ralf Salomon
Venue:  (1995)

This technical report shows under which conditions the complexity of a genetic algorithm scales with O(n ln n) when applied to multimodal functions.
Adding Contracts to Java with Handshake
Authors: Andrew Duncan, Urs Hoelzle
Venue:  (1998)

Contracts describe an agreement between the writer and the user of a class. Their use enhances programmer productivity and program reliability, especially in library code. Handshake provides contracts for Java classes and interfaces in the form of class invariants and method pre- and postconditions. Using Handshake, a programmer can add contracts to classes and interfaces without needing access to their source code, without changing the class files, and without changing the JVM implementation. Unlike existing implementations of contracts for Java, Handshake intercepts the VM''s file operations and modifies classes on the fly without requiring any modification to the JVM itself. By using a dynamic link library interposed between the VM and the operating system, the system is relatively simple to port to a new OS and works with a variety of JVM implementations. The system imposes very little overhead other than the time required to evaluate the contract''s boolean expressions themselves.
Remote Usability Evaluation at a Glance
Authors: Castillo Jose C., Hartson H. Rex, Hix Deborah
Venue:  (1997)

Much traditional user interface evaluation is conducted in usability laboratories, where a small number of selected users is directly observed by trained evaluators. However, as the network itself and the remote work setting have become intrinsic parts of usage patterns, evaluators often have limited access to representative users for usability evaluation in the laboratory and the users'' work context is difficult or impossible to reproduce in a laboratory setting. These barriers to usability evaluation led to extending the concept of usability evaluation beyond the laboratory, typically using the network itself as a bridge to take interface evaluation to a broad range of users in their natural work settings.