ppxscal/embedding_network huggingface dataset:
Application-Layer Multicasting with Delaunay Triangulation Overlays
Authors: J. Liebeherr, M. Nahas, W. Si
Venue:  (2001)

Application-layer multicast supports group applications without the need for a network-layer multicast protocol. Here, applications arrange themselves in a logical overlay network and transfer data within the overlay. In this paper, we present an application-layer multicast solutionthat uses a Delaunay triangulation as an overlay network topology. An advantage of using a Delaunay triangulation is that it allows each application to locally derive next-hop routing information without requiring a routing protocol in the overlay. A disadvantage of using a Delaunay triangulation is that the mapping of the overlay to the network topology at the network and data link layer may be suboptimal. We present a protocol, called "Delaunay Triangulation (DT)" protocol, which constructs Delaunay triangulation overlay networks. We present measurement experiments of the DT protocol for overlay networks with up to 10,000 members, that are running on a local PC cluster with 100 Linux PCs. The results show that the protocol stabilizes quickly, e.g., an overlay network with 10,000 nodes can be built in just over 30 seconds. The traffic measurements indicate that the average overhead of a node is only a few kilobits per second if the overlay network is in a steady state. Results of throughput experiments of multicast transmissions (using TCP unicast connections between neighbors in the overlay network) show an achievable throughput of approximately 15 Mbps in an overlay with 100 nodes and 2 Mbps in an overlay with 1,000 nodes.
A Model Checker for Statecharts
Authors: Nancy Day
Venue:  (1993)

Computer-Aided Software Engineering (CASE) tools encourage users to codify the specification for the design of a system early in the development process. They often use graphical formalisms, simulation and prototyping to help express ideas concisely and unambiguously. Some tools provide little more than syntax checking of the specification but others can test the model for reachability of conditions, nondeterminism or deadlock. Formal methods include powerful tools like automatic model checking to exhaustively check a model against certain requirements. Integrating formal techniques into the system development process is an effective method of providing more thorough analysis of specifications than conventional approaches employed by Computer-Aided Software Engineering (CASE) tools. In order to create this link, the formalism used by the CASE tool must have a precise formal semantics that can be understood by the verification tool. The CASE tool STATEMATE makes use of an extended state transition notation called statecharts. We have formalized an operational semantics for statecharts by embedding them in the logical framework of an interactive proof-assistant system called HOL. A software interface is provided to extract a statechart directly from the STATEMATE database. Using HOL in combination with Voss, a binary decision diagram-based verification tool, we have developed a model checker for statecharts which tests whether an operational specification, given by a statechart, satisfies a descriptive specification of the system requirements. The model checking procedure is a simple higher-order logic function which executes the semantics of statecharts. In this technical report, we describe the formal semantics of statecharts and the model checking algorithm. Various examples, including an intersection with a traffic light and an arbiter, are presented to illustrate the method.
No Quadrangulation is Extremely Odd
Authors: Bose Prosenjit, Toussaint Godfried
Venue:  (1995)

Given a set S of n points in the plane, a quadrangulation of S is a planar subdivision whose vertices are the points of S, whose outer face is the convex hull of S, and every face of the subdivision (except possibly the outer face) is a quadrilateral. We show that S admits a quadrangulation if and only if S does not have an odd number of extreme points. If S admits a quadrangulation, we present an algorithm that computes a quadrangulation of S in O(n log n) time even in the presence of collinear points. If S does not admit a quadrangulation, then our algorithm can quadrangulate S with the addition of one extra point, which is optimal. We also provide an \Omega(n \log n) time lower bound for the problem. Finally, our results imply that a k-angulation of a set of points can be achieved with the addition of at most k-3 extra points within the same time bound.
Mining text documents for thematic hierarchies using self-organizing maps
Authors: Hsin-Chang Yang, Chung-Hong Lee
Venue: Data mining: opportunities and challenges (2003)

Recently, many approaches have been devised for mining various kinds of knowledge from texts. One important application of text mining is to identify themes and the semantic relations among these themes for text categorization. Traditionally, these themes were arranged in a hierarchical manner to achieve effective searching and indexing as well as easy comprehension for human beings. The determination of category themes and their hierarchical structures was mostly done by human experts. In this work, we developed an approach to automatically generate category themes and reveal the hierarchical structure among them. We also used the generated structure to categorize text documents. The document collection was trained by a self-organizing map to form two feature maps. We then analyzed these maps and obtained the category themes and their structure. Although the test corpus contains documents written in Chinese, the proposed approach can be applied to documents written in any language, and such documents can be transformed into a list of separated terms.
Geometric Performance Analysis of Mutual Exclusion: The Model
Authors: Marc Abrams
Venue:  (1990)

This paper is motivated by the need to better understand parallel program run-time behavior. The paper first formally describes a general model of program execution based on Djkstra''s progress graphs. The paper then defines a special case of the model representing two cyclic processes sharing mutually exclusive, reusable resources. Processes synchronize through semaphore operations that are not embedded in conditionally executed code segments. Model parameters are the times at which each semaphore operation completes and the independently derived, constant execution time required by each process between points of completion of semaphore operations.
Practical Point-in-Polygon Tests Using CSG Representations of Polygons
Authors: Robert J. Walker, Jack Snoeyink
Venue:  (1999)

We investigate the use of a constructive solid geometry (CSG) representation of polygons in testing if points fall within them; this representation consists of a tree whose nodes are either Boolean operators or edges. By preprocessing the polygons, we seek (1) to construct a space-conserving data structure that supports point-in-polygon tests, (2) to prune as many edges as possible while maintaining the semantics of our tree, and (3) to obtain a tight inner loop to make testing the remaining edges as fast as possible. We utilize opportunities to optimize the pruning by permuting sibling nodes. We find that this process is less memory-intensive than the grid method and faster than existing one-shot methods.
When is it Possible to Identify 3D Objects from Single Images Using Class Constraints?
Authors: R. Basri, Y. Moses
Venue:  (1997)

One approach to recognizing objects seen from arbitrary viewpoint is by extracting invariant properties of the objects from single images. Such properties are found in images of 3D objects only when the objects are constrained to belong to certain classes (e.g., bilaterally symmetric objects). Existing studies that follow this approach propose how to compute invariant representations for a handful of classes of objects. A fundamental question regarding the invariance approach is whether it can be applied to a wide range of classes. To answer this question it is essential to study the set of classes for which invariance exists. This paper introduces a new method for determining the existence of invariance for classes of objects together with the set of images from which these invariance can be computed. We develop algebraic tests that, given a class of objects undergoing affine projection, determine whether the objects in the class can be identified from single images. In addition, these tests allow us to determine the set of views of the objects which are degenerate. We apply these tests to several classes of objects and determine which of them is identifiable and which of their views are degenerate.
A Parallel Watershed Algorithm
Authors: Andreas Bieniek, Hans Burkhardt, H. Marschner, Michael Nolle, Gerald Schreiber
Venue:  (1996)

The watershed transformation is a popular image segmentation algorithm for grey scale images. Sequential watershed algorithms perform a highly data dependent flooding process over the global image. Because of global data dependencies over the sub-domains parallel algorithms which distribute the image over the available processors and simulate the flooding process have a limited speedup. The achievable speedup is highly data dependent. In this paper we show that it is possible to achieve a data independent speedup for images without plateaus. This can be done by inserting temporary labels where the solution depends on neighboring results. We show that the local solutions can be merged to a global solution in a data-independent way.
Automating the Generation of Interactive Applications
Authors: Emanuel G. Noik
Venue:  (1990)

As user interfaces become more powerful and easier to use they are often harder to design and implement. This has caused a great demand for interface tools. While existing tools ease interface creation, they typically do not provide mechanisms to simplify application development and are too low-level. Furthermore, existing tools do not provide effective mechanisms to port interactive applications across user interfaces. While some tools provide limited mechanisms to port applications across user interfaces which belong to the same class (e.g., the class of all standard graphical direct-manipulation user interfaces), very few can provide the ability to port applications across different interface classes (e.g., command-line, hypermedia, speech recognition and voice synthesis, virtual reality, etc.). \n With my approach, the programmer uses an abstract model to describe the structure of the application including the information that the application must exchange with the user, rather than describing a user interface which realizes these characteristics. By specifying application semantics at a very high level of abstraction it is possible to obtain a much greater separation between the application and the user interface. Consequently, the resulting applications can be ported not only across user interfaces which belong to a common interface class, but across interfaces which belong to distinct classes. This can be realized through simple recompilation --- source code does not have to be modified. \n NAAG (Not Another Application Generator), a tool which embodies these ideas, enables programmers to create interactive applications with minimal effort. An application is modelled as a set of operations which manipulate objects belonging to user-defined object classes. The input to NAAG is a source program which describes classes, operations and their inputs and outputs, and the organization of operations within the application. Classes and operations are implemented as data structures and functions in a conventional programming language such as C. This model simplifies not only the specification and generation of the user interface, but the design and implementation of the underlying application. \n NAAG utilizes existing technology such as macro-preprocessors, compilers, make programs, and low-level interface tools, to reduce the programming task. An application that is modified by adding, removing, or reorganizing artifacts (classes, operations, and menus), can be regenerated with a single command. Traditionally, software maintenance has been a very difficult task as well. Due to the use of a simple abstract model, NAAG applications are also easier to maintain. Furthermore, this approach encourages software reuse: applications consisting of arbitrary collections of original and pre-existing artifacts can be composed easily; functions which implement abstract operations are independent of both, user interface aspects, and the context in which they are
Sframe: An Efficient System for Detailed DC Simulation of Bipolar Analog Integrated Circuits Using Continuation Methods
Authors: Robert C. Melville, Shahriar Moinian, Peter Feldman, Layne T. Watson
Venue:  (1992)

In this paper we describe an experimental system called sframe which is being incorporated into the design for manufacturability initiative at the Reading Works of AT&T Bell Laboratories. Our system is able to perform detailed and accurate DC analyses of integrated circuits containing several hundred transistors to be fabricated in a relatively complex junction isolated complementary technology.
Analysis of Mammographic Densities
Authors: Alison A. Dingle
Venue:  (1995)

Abstract unavailable.
PERFECT-BALANCE PLANAR CLOCK ROUTING WITH MINIMAL PATH LENGTH
Authors: Qing Zhu, Wayne W.M. Dai
Venue:  (1993)

The design of high speed digital VLSI circuits prefers that the clock net is routed on the metal layer with the smallest RC delay. This strategy not only avoids the difficulties of having different electrical parameters on different layers, but also eliminates the delay and attenuation of the clock signal through vias. The clock phase-delay is also decreased. In this paper, we present a novel algorithm, based on hierarchical max-min optimization, to construct a planar clock tree which can be embedded on a single metal layer. The clock tree achieves equal path length---the length of the path from the clock source to each clock terminal is exactly the same. In addition, the path length from the source to clock terminals is minimized. Some examples including industrial benchmarks have been tested and the results are promising. We further optimize the geometry of the clock tree to minimize both the skew and path delay of the clock signal while maintaining the planarity of the clock network. Some premilinary results are promising which achieve near zero skew by using SPICE simulation.(Supersedes UCSC-CRL-92-12)
Real-Time Multivariate Data Visualization Using Preattentive Processing
Authors: Christopher G. Healey, Kellogg S. Booth, James T. Enns
Venue:  (1994)

A new method is presented for visualizing data as they are generated from real-time applications. These techniques allow viewers to perform simple data analysis tasks such as detection of data groups and boundaries, target detection, and estimation. The goal is to do this rapidly and accurately on a dynamic sequence of data frames. Our techniques take advantage of an ability of the human visual system called preattentive processing. Preattentive processing refers to an initial organization of the visual system based on operations believed to be rapid, automatic, and spatially parallel. Examples of visual features that can be detected in this way include hue, orientation, intensity, size, curvature, and line length. We believe that studies from preattentive processing should be used to assist in the design of visualization tools, especially those for which high speed target, boundary, and region detection are important. Previous work has shown that results from research in preattentive processing can be used to build visualization tools which allow rapid and accurate analysis of individual, static data frames. We extend these techniques to a dynamic real-time environment. This allows users to perform similar tasks on dynamic sequences of frames, exactly like those generated by real-time systems such as visual interactive simulation. We studied two known preattentive features, hue and curvature. The primary question investigated was whether rapid and accurate target and boundary detection in dynamic sequences is possible using these features. Behavioral experiments were run that simulated displays from our preattentive visualization tools. Analysis of the results of the experiments showed that rapid and accurate target and boundary detection is possible with both hue and curvature. A second question, whether interactions occur between the two features in a real-time environment, was answered positively. This suggests that these and perhaps other visual features can be used to create visualization tools that allow high-speed multidimensional data analysis for use in real-time applications. It also shows that care must be taken in the assignment of data elements to preattentive features to avoid creating certain visual interference effects.
Dateien in f&#x00F6;derierten Datenbanksystemen
Authors: Kö, Andreas ller
Venue:  (1996)

Untersuchungen an Systemen zur Fabrikplanung
A CONSTRAINT-BASED SKIN MODEL FOR HUMAN FIGURE ANIMATION (M.S. Thesis)
Authors: Mark Henne
Venue:  (1990)

One of the difficult problems in computer character animation has been creating a skin model which deforms naturally over joints. A method for solving this problem is described, which includes such desirable characteristics as the formation of creases on the inside of joints and muscle bulging during flexing. In this model the skin is represented using a mesh of bicubic surface patches, with the control points acting as sample points in a constraint balancing equation. Two main constraints are used: the skin is described as a flexible surface that resists stretching, and bones, fat, and muscle are represented by localized fields pushing out on the skin. The final shape of the figure is a compromise between the skin''s surface area constraints and the arrangement of underlying tissue. Modeling with bicubic patches allows the granularity of the constraint computations to be much more coarse than if a polygonal model were used, and provides for well-defined and stable surface texture coordinates. In addition, this method is capable of incorporating tissue-bouncing due to rigid body motion.
Data mining from clinical data using interactive evolutionary computation
Authors: Takao Terano, Masanori Inada
Venue: Advances in evolutionary computing: theory and applications (2003)

Interactive evolutionary computation (IEC) is a subjective and interactive method to evaluate the qualities of offspring generated by genetic operations. Data mining, an interdisciplinary research area including artificial intelligence, statistics and databases, is a series of semi-automated processes to extract explicit useful knowledge from given databases. In this chapter, we adopt IEC in order to select relevant features in inductive learning for data mining tasks. The method we have proposed is used to discover efficient decision knowledge from noisy clinical data in a medical domain. This chapter describes the principles of IEC and SIBILE (Simulated Breeding and Inductive Learning), which we have developed for practical data mining problems, and its application to a common data set on clinical patients, The basic ideas of SIBILIE are that IEC is used to get the effective feature, from the data and that inductive learning is used to acquire simple decision rules from the subset of the data.
Optimal Binary Space Partitions for Orthogonal Objects
Authors: M. S. Paterson, F. F. Yao
Venue:  (1990)

A binary space partition, or BSP is a scheme for recursively dividing a configuration of objects by hyperplanes until all objects are separated. BSPs are widely used in computer graphics as the underlying data structure for computations such as real-time hidden-surface removal, ray tracing, and solid modelling. In these applications, the computational cost is directly related to the size of the BSP, ie the toal number of fragments of the objects generated by the partition. Until recently, the question of minimizing the size of BSPs for given inputs had been studied only empirically. We concentrate here on ortogonal objects, a case which arises frequently in practice and deserves special attention. We construct BSPs of linear size for any set of orthogonal line segments in the plane. In three dimensions, BSPs of size O(n^1.5) for any set of n mutually orthogonal line segments or rectangles are constructed. These bounds are optimal and may be contrasted with the omega(n^2) bound for general polygonal objects in R^3.
A Real Time Robot Arm Collision Detection System
Authors: Clifford A. Shaffer, Gregory M. Herb
Venue:  (1990)

A data structure and update algorithm are presented for a prototype real time collision detection safety system for a multi-robot environment. The data structure is a variant of the octree, which serves as a spacial index. An octree recursively decomposes three dimensional space into eight equal cubic octans until each octant meets some decomposition criteria. Our octree stores cylspheres (cylinders with spheres on each end) and rectangular solids as primitives (other primitives can easily be added as required). These primitives make up the two seven-degrees-of-freedom robot arms and environment modeled by the system. Octree nodes containing more than a predetermined number N of primitives are decomposed. This rule keeps the octree small, as the entire environment for our application can be modeled using a few dozen primitives. As robot arms move, the octree is updated to reflect their changed positions. During most update cycles, any given primitive does not change which octree node it is in. Thus, modification to the octree is rarely required. Incidents in which one robot arm comes too close to another arm or an object are reported. Cycle time for interpreting current joint angles, updating the octree, and detecting/reporting imminent collisions averages 30 milliseconds on an Intel 80386 processor running at 20 MHz.
How Realistic Should a Software Project Course Be?
Authors: William Mitchell
Venue: Journal of Computing Sciences in Colleges (1991)

The author has argued elsewhere in favor of the experiential learning objectives of a software project course and has noted that the computer education literature is replete with descriptions of project courses which vary from systems analysis only to complete implementations of software systems. This paper advocates the production and delivery of a software product in a project course, but reports favorable experience with an "academic" rather than "realistic" project management structure. This experience motivates reflection as to the value of trying to replicate all aspects of the industrial environment in academe.
A GENERAL MINIMAX RESULT FOR RELATIVE ENTROPY
Authors: David Haussler
Venue:  (1996)

Suppose Nature picks a probability measure P on a complete separable metric space X at random from a fixed set of probability measures. Then, without knowing which measure is picked, a statistician picks a measure Q on X. Finally, the statistician suffers a loss equal to the relative entropy between P and Q. We show that the minimax and maximin values of this game are always equal, and there is always a minimax strategy in the closure of the set of all Bayes strategies. This generalizes previous results of Gallager, and Davisson and Leon-Garcia.