ppxscal/embedding_network huggingface dataset:
Shape Transformations Using Union of Spheres
Authors: Vishwa Ranjan, Alain Fournier
Venue:  (1995)

Shape interpolation is the process of transforming continuously one object into another. This is useful in applications such as object recognition, object registration and computer animation. Unfortunately, "good" shape interpolation is as ill-defined as "shape" itself. To be able to control the process in a useful way, we need a representation for the objects using primitives which capture at least some aspects of their shape, with methods to convert other representations to this one. We present here a method to interpolate between two objects represented as a union of spheres. We briefly describe the representation and its properties, and show how to use it to interpolate. Once a distance metric between the spheres is defined (we show different metric producing controlled effects), the algorithm optimally matches the spheres in the two models using a bipartite graph. The transformation then consists in interpolating between the matched spheres. If the union of spheres has been simplified, the other spheres are matched as a function of their positions within their representative cluster. Examples are shown and discussed with two- and three-dimensional objects. The results show that the union of spheres helps capture some notion of shape, and helps to automatically match and interpolate shapes.
Vision-Guided Flame Control using Fuzzy Logic and Neural Networks (invitedpaper)
Authors: Wenjing Tao, Hans Burkhardt
Venue:  (1995)

This paper presents an application of fuzzy and neural network techniques to a vision-guided closed loop control for stationary luminous flames. The image processing technique is used to analyze and identify the process states. Fuzzy control strategy avoids the difficulty in establishing a mathematical model for an ill-defined process. Expert knowledge and training patterns can be incorporated into fuzzy rules, which are represented in the form of neurons. The use of a neural network makes it easy to increase the number of control parameters and provides the system the possibility to adjust its performance automatically.
A Framework for Semantic Reasoning about Byzantine Quorum Systems
Authors: Evelyn Pierce, Lorenzo Alvisi
Venue:  (2001)

We present a set of definitions and theorems that allow us to reason about the semantics of quorum system variables, including Byzantine quorum system variables, as a class. Using these tools, we present a formal proof that the problem of atomic semantics for such variables can be reduced to the simpler problem of regular semantics for such systems. Specifically, any regular masking quorum system protocol can be combined with a writeback mechanism to produce an atomic protocol. We then describe a subclass of TS-variables for which the latter problem is not solvable by traditional approaches in an asynchronous environment. Finally, for such variables we define the notion of pseudoregular and pseudoatomic semantics, and show briefly that the same reduction holds for these concepts.
Algorithms for Almost-uniform Generation with an Unbiased Binary Source
Authors: Omer Egecioglu, Marcus Peinado
Venue:  (1998)

We consider the problem of uniform generation of random integers in the range $[1 , n]$ given only a binary source of randomness. Standard models of randomized algorithms (e.g. probabilistic Turing machines) assume the availability of a random binary source that can generate independent random bits in unit time with uniform probability. This makes the task trivial if $n$ is a power of $2$. However, exact uniform generation algorithms with bounded run time do not exist if $n$ is not a power of $2$. We analyze several {\em almost-uniform} generation algorithms and discuss the tradeoff between the distance of the generated distribution from the uniform distribution, and the number of operations required per random number generated. In particular, we present a new algorithm which is based on a circulant, symmetric, rapidly mixing Markov chain. For a given positive integer $N$, the algorithm produces an integer $i$ in the range $[1,n]$ with probability $p_i= p_i(N)$ using $O(N \log n )$ bit operations such that $| p_i - 1/n | > c \beta^N$, for some constant $c$, where \[ \beta = \frac{2^{\frac{1}{4}} }{\pi} \left( \sqrt{2\sqrt{2} - \sqrt{5- \sqrt{5}}} ~\right) \approx 0.4087.\] This rate of convergence is superior to the estimates obtainable by commonly used methods of bounding the mixing rate of Markov chains such as conductance, direct canonical paths, and couplings.
LAYER ASSIGNMENT FOR RUBBER BAND ROUTING
Authors: Tal Dayan, Wayne W Dai
Venue:  (1993)

The flexibility of the rubber-band wire model is very promising for routing and optimizing today''s complex VLSI and MCM. In this paper we described a practical layer assignment algorithm used with a rubber band router. The algorithm uses a steepest descent approach with an heuristic function which estimate the wiring length of the generated assignment. We formulate the cost function and present an efficient way to compute it. The use of the cost function enable to control the final layout and to achieve balance between wire length and number of vias. The algorithm can be use as well for cost-driven one an a half layer designs in which one wiring layer has only short "jumpers" and is embedded in the ground layer.
Data Transfer Scheduling
Authors: Kiran K Somalwar
Venue:  (1988)

The problem of data transfer scheduling is a problem of multiple resource allocation. It is cast as an edge coloring problem. Several exact algorithms for edge coloring, in the literature, are described. A new algorithm for edge coloring, when no color can be used more than k times, is designed and analyzed. Several inexact algorithms are described and evaluated for their cost effectiveness.
A TAXONOMY OF RACE CONDITIONS
Authors: D. P. Helmbold, C. E. McDowell
Venue:  (1994)

Parallel programs are frequently non-deterministic, meaning they can give different results when provided the same input. These different results arise because variations in the timing of the multiple threads cause the threads to access shared resources in different orders. The phenomena that cause the non-deterministic behavior have been (and continue to be) variously referred to as access anomalies, race conditions or just races. In a recent paper, Netzer and Miller made an important contribution to formalizing and standardizing adjectives that can be applied to ``races.'''' In this paper we continue this effort by presenting a refined taxonomy for races in parallel programs. The terminology we suggest is not always consistent with that used previously and we describe why we believe our terminology is more descriptive.
VPI Prolog User Manual
Authors: John W. Roach, John Deighan
Venue:  (1990)

This paper documents how a user may work with the VPI Prolog compiler. The user interface functions called debugging environment and input/output are all described in detail. Anyone using this manual should be able to program effectively using VPI Prolog.
Generalized LL(K) grammars for Concurrent Logic Programming Languages
Authors: Harvey Abramson
Venue:  (1987)

We examine the compilation of the LL(k) deterministic context free grammars to Horn clause logic programs and sequential and concurrent execution of these programs. In the sequential case, one is able to take advantage of the determinism to eliminate the generation of unnecessary backtracking information during execution of the compiled logic program. In the concurrent case, grammar rules are simply and directly translated to clauses of Concurrent Prolog, Parlog, or Guarded Horn Clause programs, allowing grammatical processing directly in the setting of committed or ``don''t care'''' nondeterminism. LL(k) grammar rules are generalized so that grammatical processing of streams involving derivations of infinite length is possible. A top-down analogue of Marcus''s deterministic parser is a possible application of these generalized LL(k) grammars.
Local Majority Voting, Small Coalitions and Controlling Monopolies in Graphs: A Review
Authors: D. Peleg
Venue:  (1996)

This paper provides an overview of recent developments concerning the process of local majority voting in graphs, and its basic properties, from graph theoretic and algorithmic standpoints.
Scaling an Object-Oriented System Execution Visualizer Through Sampling
Authors: Andrew Chan, Reid Holmes, Gail C. Murphy, Annie T.T. Ying
Venue:  (2002)

Increasingly, applications are being built by combining existing software components. For the most part, a software developer can treat the components as black-boxes. However, for some tasks, such as when performance tuning, a developer must consider how the components are implemented and how they interact. In these cases, a developer may be able to perform the task more effectively by using dynamic information about how the system executes. In previous work, we demonstrated the utility of a tool, called AVID (Architectural VIsualization of Dynamics), that animates dynamic information in terms of developer-chosen architectural views. One limitation of this earlier work was that AVID relied on trace information collected about the system''s execution, limiting the duration of execution that could be considered. To enable AVID to scale to larger, longer-running systems, we have been investigating the visualization and animation of sampled dynamic information. In this paper, we discuss the addition of sampling support to AVID, and we present two case studies in which we experimented with animating sampled dynamic information to help with performance tuning tasks.
Performance Evaluation of Object-Oriented Active Database ManagementSystems Using the BEAST Benchmark
Authors: Andreas Geppert, Mikael Berndtsson, Daniel Lieuwen, Claudia Roncancio
Venue:  (1996)

This paper uses the BEAST benchmark to present the first serious performance study of object-oriented active database management systems (ADBMS). BEAST stresses the performance-critical components of active systems: event detection, event composition, rule retrieval, and rule firing. Method invocation events and transactional events are taken into account. Four systems, namely ACOOD, NAOS, Ode, and SAMOS, have been tested with the benchmark tests of BEAST. The performance measurements demonstrate achievements in the area of active database technology, but also indicate tradeoffs (e.g. between performance and functionality). Finally, the benchmark identifies optimizations and provides hints to ADBMS desigers about producing systems with adequate performance and functionality --- as well as some open issues.
A Feedback Control Architecture and Design Methodology for Service Delay Guarantees in Web Servers
Authors: Chenyang Lu, Tarek F. Abdelzaher, John A. Stankovic, Sang H. Son
Venue:  (2001)

This paper presents the design and implementation of an adaptive architecture to provide relative, absolute and hybrid service delay guarantees for different service classes on web servers under HTTP 1.1. The first contribution of this paper is the architecture based on feedback control loops that enforce delay guarantees for classes via dynamic connection scheduling and process reallocation. The second contribution is our use of feedback control theory to design the feedback loop with proven performance guarantees. In contrast with ad hoc approaches that often rely on laborious tuning and design iterations, our control theory approach enables us to systematically design an adaptive web server with established analytical methods. The design methodology includes using system identification to establish dynamic models for a web server, and using the Root Locus method to design feedback controllers to satisfy performance specifications. The adaptive architecture has been implemented by modifying an Apache web server. Experimental results demonstrate that our adaptive server provides robust delay guarantees even when workload varies significantly. Properties of our adaptive web server also include guaranteed stability, and satisfactory efficiency and accuracy in achieving desired delay or delay differentiation.
Clause Management System
Authors: George K. Tsiknis, Alex Kean
Venue:  (1988)

In this paper, we study the full extent of the Clause Management System(CMS) proposed by Reiter and de Kleer. The CMS is adapted specifically for aiding a reasoning system (Reasoner) in explanations generation. The Reasoner transmits propositional formulae representing its knowledge to the CMS and in return, the Reasoner can query the CMS for concise explanations w.r.t the CMS knowledge base. We argue that based on the type of tasks the CMS performs, it should represent its knowledge base $\Sigma $ using a set of prime implicates $PI(\Sigma )$. The classification of implicates as prime, minimal, trivial and minimal trivial is carefully examined. Similarly, the notion of a support (or roughly, an explanation) for a clause including prime, minimal, trivial and minimal trivial is also elaborated. The methods to compute these supports from implicates and a preference ordering schema for the set of supports for a given clause are also presented. The generalization of the notion of a minimal support for a conjunction of clauses is also shown. Finally, two logic based diagnostic reasoning paradigms aided by the CMS are shown to exemplify the functionality of the CMS.
Sluice: A Java-Based Framework for Collaborative Interactive Modular Visualization Environments
Authors: Isenhour Philip, Shaffer Clifford A., Begole James, Nielsen Jeff, Abrams Marc
Venue:  (1997)

We present Sluice, a framework for constructing collaborative, interactive, modular visualization environments (CIMVEs) for use on the World Wide Web. Sluice supports using Java to build modules that create, manipulate, and generate visualizations of tables of data. Sluice provides necessary infrastructure for a CIMV, including interface specifications for methods that modules of the MVE must implement, event propagation to support interaction and dynamic updating, and mechanisms for efficiently supporting collaboration. Our fundamental description of data comes in the form of table which is filtered, extended, or otherwise manipulated to produce a new "view" of the data at each module. We use the observer/observable design pattern to support dynamic updating of visualizations downstream in the dataflow network. Sluice also supports on-the-fly manipulation of the dataflow network. Sluice uses functionality provided by the JavaBeans package to support introspection of modules. This allows CIMVE implementations to discover, query, and set the values of properties of modules at runtime. After describing the design rationale, capabilities, and implementation of Sluice, we then describe our prototype CIMVE named SIEVE.
DIRECT VOLUME RENDERING WITH SHADING VIA THREE-DIMENSIONAL TEXTURES
Authors: Allen VanGelder, Kwansik Kim
Venue:  (1996)

A new and easy-to-implement method for direct volume rendering that uses 3D texture maps for acceleration, and incorporates directional lighting, is described. The implementation, called Voltx, produces high-quality images at nearly interactive speeds on workstations with hardware support for three-dimensional texture maps. Previously reported methods did not incorporate a light model, and did not address issues of multiple texture maps for large volumes. Our research shows that these extensions impact performance by about a factor of ten. Voltx supports orthographic, perspective, and stereo views. This paper describes the theory and implementation of this technique, and compares it to the shear-warp factorization approach. A rectilinear data set is converted into a three-dimensional texture map containing color and opacity information. Quantized normal vectors and a lookup table provide efficiency. A new tesselation of the sphere is described, which serves as the basis for normal-vector quantization. A new gradient-based shading criterion is described, in which the gradient magnitude is interpreted in the context of the field-data value and the material classification parameters, and not in isolation. In the rendering phase, the texture map is applied to a stack of parallel planes, which effectively cut the texture into many slabs. The slabs are composited to form an image.
Embedding supspaces of Lp into \lscrNp, 0 > p > 1
Authors: G. Schechtman, Z. Zvavitch
Venue:  (1999)

It is shown that if X is n-dimensional subspace of Lp, 0 > p > 1, then there exists a subspace Y of \lscrNp such that d(X,Y) # 1+e and N # C(e,p)n(logn)3.
Specifying Modules to Satisfy Interfaces: a State Transition System
Authors: Simon S. Lam, A. U Shankar
Venue:  (1990)

We define interface, module and the meaning of M offers I, where M denotes a module and I an interface. For a module M and disjoint interfaces U and L, the notion M using L offers U is also defined. Our theory is applied to solve a problem posed by Leslie Lamport at the 1987 Lake Arrowhead Workshop. We first present a formal specification of a serializable database interface. We then provide specifications of two modules, one based upon two-phase locking and the other multi-version timestamps; the two-phase locking module uses an interface offered by a physical database. We prove that each module offers the serializable interface.
Parallel and Distributed Finite Constraint Satisfaction: Complexity, Algorithms and Experiments
Authors: Ying Zhang, Alan K. Mackworth
Venue:  (1992)

This paper explores the parallel complexity of finite constraint satisfaction problems (FCSPs) by developing three algorithms for deriving minimal constraint networks in parallel. The first is a parallel algorithm for the EREW PRAM model, the second is a distributed algorithm for fine-grain interconnected networks, and the third is a distributed algorithm for coarse-grain interconnected networks. Our major results are: given an FCSP represented by an acyclic constraint network (or a join tree) of size n with treewidth bounded by a constant, then (1) the parallel algorithm takes O(log n) time using O(n) processors, (2) there is an equivalent network, of size poly(n) with treewidth also bounded by a constant, which can be solved by the fine-grain distributed algorithm in O(\log n) time using poly(n) processors and (3) the distributed algorithm for coarse-grain interconnected networks has linear speedup and linear scaleup. In addition, we have simulated the fine-grain distributed algorithm based on the logical time assumption, experimented with the coarse-grain distributed algorithm on a network of transputers, and evaluated the results against the theory.
Analysis of Binomial Congestion Control
Authors: Y. R Yang, Simon S. Lam
Venue:  (2000)

Binomial congestion control was proposed by Bansal and Balakrishnan in [2]. However, the sending rate derivation in [2] is greatly simplified and does not consider the effect of timeouts. The motivation of this paper is to analyze the sending rate of binomial congestion window adjustment policy, considering both tripli-duplicate loss indications and timeout loss indications. We also consider the selection of "alpha" and "beta" for HAD and SQRT congestion control strategies [2] to be TCP-friendly. This paper suggests that the authors of Binomial should test their protocol under higher loss scenarios. The balance of this paper is as follows. In Section 2, we describe the Binomial congestion control and state the analysis assumptions. The detail of the derivations is put in the Appendix. In Section 3, we use the sending rate formula to derive conditions under which a Binomial flow is TCP-friendly.
An Evaluation of Architectural Alternatives for Rapidly Growing Datasets: Active Disks, Clusters, SMPs
Authors: Mustafa Uysal, Anurag Acharya, Joel Saltz
Venue:  (1998)

Growth and usage trends for several large datasets indicate that there is a need for architectures that scale the processing power as the dataset increases. In this paper, we evaluate three architectural alternatives for rapidly growing and frequently reprocessed datasets: active disks, clusters, and shared memory multiprocessors (SMPs). The focus of this evaluation is to identify potential bottlenecks in each of the alternative architectures and to determine the performance of these architectures for the applications of interest. We evaluate these architectural alternatives using a detailed simulator and a suite of nine applications. Our results indicate that for most of these applications Active Disk and cluster configurations were able to achieve significantly better performance than SMP configurations. Active Disk configurations were able to match (and in some cases improve upon) the performance of commodity cluster configurations.
Fingerprint Theorems for Curvature and Torsion Zero-Crossings
Authors: Farzin Mokhtarian
Venue:  (1988)

The {\em scale space image} of a signal f(x) is constructed by extracting the zero-crossings of the second derivative of a Gaussian of variable size a convolved with the signal, and recording them in the $x-\sigma $ map. \n Likewise, the {\em curvature scale space image} of a planar curve is computed by extracting the curvature zero-crossings of a parametric representation of the curve convolved with a Gaussian of variable size. The curvature level-crossings and torsion zero-crossings are used to compute the {\em curvature} and {\em torsion scale space images} of a space curve respectively. \n It has been shown [Yuille and Poggio 1983] that the scale space image of a signal determines that signal uniquely up to constant scaling and a harmonic function. This paper presents a generalization of the proof given in [Yuille and Poggio 1983]. It is shown that the curvature scale space image of a planar curve determines the curve uniquely, up to constant scaling and a rigid motion. Furthermore, it is shown that the torsion scale space of a space curve determines the function $\tau (u) \kappa ^{2} (u)$ modulus a scale factor where $\tau (u)$ and $\kappa (u)$ represent the torsion and curvature functions of the curve respectively. Our results show that a 1-D signal can be reconstructed using only one point from its scale space image. This is an improvement of the result obtained by Yuille and Poggio. \n The proofs are constructive and assume that the parametrizations of the curves can be represented by polynomials of finite order. The scale maps of planar and space curves have been proposed as representations for those curves [Mokhtarian and Mackworth 1986, Mokhtarian 1988]. The result that such maps determine the curves they are computed from uniquely, shows that they satisfy an important criterion for any shape representation technique.
EFFECTS OF COEFFICIENT CODING ON JPEG BASELINE IMAGE COMPRESSION
Authors: Manyun Chang, Glen G. Langdon,  Jr., James L. Murphy
Venue:  (1991)

A set of still image compression algorithms JPEG (Joint Photographic Experts Group) is becoming an international standard. Here we apply a methodology to study the compression obtained by each step of the three-step baseline algorithm chosen by JPEG. We also present our results, observations and analysis on simulating the JPEG sequential baseline system. The primary compression gain comes from run-length coding of zero coefficients. Based on our simulator, a comparison of Huffman coder, arithmetic coder and LZW algorithm is also included.