ppxscal/embedding_network huggingface dataset:
A Visualization System for Correctness Proofs of Graph Algorithms
Authors: Peter A. Gloor, Donald B. Johnson, Fillia Makedon, Panagiotis Metaxas
Venue:  (1992)

In this paper we describe a system for visualizing correctness proofs of graph algorithms. The system has been demonstrated for a greedy algorithm. Prim?s algorithm for finding a minimum spanning tree of an undirected, weighted graph. We believe that our system is particularly appropriate for greedy algorithms, though much of what we discuss can guide visualization of proofs in other contexts. While an example is not a proof, our system provides concrete examples to illustrate the operation of the algorithm. These examples can be referred to by the user interactively and alternatively with the visualization of the proof where the general case is portrayed abstractly.
Optimal Algorithms for Finding User Access Sessions from Very Large Web Logs
Authors: Zhixiang Chen, Ada Wai-Chee Fu, Frank Chi-Hung Tong
Venue: World Wide Web (2003)

Although efficient identification of user access sessions from very large web logs is an unavoidable data preparation task for the success of higher level web log mining, little attention has been paid to algorithmic study of this problem. In this paper we consider two types of user access sessions, interval sessions and gap sessions. We design two efficient algorithms for finding respectively those two types of sessions with the help of some proposed structures. We present theoretical analysis of the algorithms and prove that both algorithms have optimal time complexity and certain error-tolerant properties as well. We conduct empirical performance analysis of the algorithms with web logs ranging from 100 megabytes to 500 megabytes. The empirical analysis shows that the algorithms just take several seconds more than the baseline time, i.e., the time needed for reading the web log once sequentially from disk to RAM, testing whether each user access record is valid or not, and writing each valid user access record back to disk. The empirical analysis also shows that our algorithms are substantially faster than the sorting based session finding algorithms. Finally, optimal algorithms for finding user access sessions from distributed web logs are also presented.
Approximation Algorithms for Geometric Median Problems
Authors: Jyh Lin, Jeffrey S Vitter
Venue:  (1992)

In this paper we present approximation algorithms for median problems in metric spaces and fixed-dimensional Euclidean space. Our algorithms use a new method for transforming an optimal solution of the linear program relaxation of the s-median problem into a provably good integral solution. This transformation technique is fundamentally different from the methods of randomized and deterministic rounding in the literature in the following way: Previous techniques never set variables with zero values in the fractional solution to 1. This departure from previous methods is crucial for the success of our algorithms.
Resolvable group divisible designs with block size four and group size six
Authors: G. Ge, C. W. H. Lam
Venue: Discrete Mathematics (2003)

In this paper, we continue the investigation for the existence of resolvable group divisible designs with block size four, group-type hn and index unity. The necessary conditions for such a design are n ≥ 4, hn ≡ 0(mod 4) and h(n - 1) ≡ 0(mod 3). The existence of these designs depends mainly on the cases h = 1, 2, 3, 6 and 12. Up to now, more than half of these cases have been solved or almost solved except for h = 2 and 6. We shall show that the above necessary conditions are also sufficient for h = 6 except n = 4 and possibly excepting n ∈ {6, 52, 54, 58, 62, 68, 74, 102, 114, 124}.
Register Allocation Using Control Trees
Authors: Kathleen Knobe, Kenneth Zadeck
Venue:  (1992)

Register allocation is like trying to fit blocks in a box. There are two distinct problems: first, the volume of the blocks may be too large for the box, and second, the shapes of the blocks may make the box difficult to pack. No matter how good your packing technique is, you cannot succeed if the volume of blocks is too large. On the other hand, that the volume of blocks is acceptable does not guarantee that the box can be packed. In the analogy to register allocation, each live range associated with a candidate (object to be allocated) is a block. Other algorithms view blocks as having uniform density. Our blocks have {\em holes}, regions in which the candidate''s live range is reference-free. We prune portions of the program where the number of live candidates is greater than the number of registers (the {\em register pressure} is too high) by storing the value in memory on entry to the region and reloading it on exit. It is always possible to prune enough that the volume of the candidates does not exceed the volume of the box. In theory, once the volume problem is solved, packing is easy if one has a chainsaw: when something doesn''t fit, cut it in two and try again. In practice, the problem is difficult to solve well because splitting has a cost: {\tt move} instructions must be inserted between the split regions. It is important to select not only the proper candidate to split but also the proper location of the split to facilitate packing the remaining blocks and also to minimize the costs of the {\tt move} instructions. Both the pruning and the splitting use the {\em control tree} to take into account the program structure in determining costs. Since the algorithm uses the control tree to guide the pruning and splitting decisions, the algorithm is called {\em control-tree register allocation} algorithm.
Specification of Secure Distributed Collaboration Systems
Authors: Anand R. Tripathi, Tanvir Ahmed, Richa Kumar
Venue: Proceedings of the The Sixth International Symposium on Autonomous Decentralized Systems (ISADS'03) (2003)

The focus of this paper is on a specification model for defining security and coordination policies for distributed collaboration and workflow systems. This work is motivated by the objective to build distributed collaboration systems from their high level specifications. We identify here unique requirements for secure collaboration, specifically role admission and activation constraints, separation of duties, dynamic access control, and a model for multi-user participation in a role. We present a role-based model for specifying coordination and dynamic security requirements in collaboration systems. It also supports hierarchical structuring of a large collaboration environment using the concept of activities, which define a naming scope and a protection domain to specify security and coordination policies. We have implemented this specification model in XML and used it to construct the runtime environments for distributed collaboation systems using a policy based middleware.
Search Engine Optimization with Webposition Gold
Authors: Brad S. Konia, Brent Winters
Venue:  (2002)

:Setting up a web site is only half the job; making sure people can find the site is the other. The higher your site ranks in the search engines, the greater the likelihood that the site will attract qualified traffic, resulting in increased sales. Search engine optimization expert Brad Konia outlines the process of maximizing search engine positioning using WebPosition Gold 2, one of the most popular search engine software tools on the market.
Dependability Assessment of GUARDS Instances
Authors: Jean Arlat, Tahar Jarboui, Karama Kanoun, David Powell
Venue: Proceedings of the 4th International Computer Performance and Dependability Symposium (2000)

The generic architectural concepts developed in the European ESPRIT project GUARDS (Generic Upgradeable Architecture for Real time Distributed Systems) provide a comprehensive framework from which specific instances can be derived to meet the dependability requirements of various application domains. Three main application domains are considered (railway, nuclear propulsion and space) that correspond to the fields of the three end-user partners of the project.This paper presents the modeling method supporting the assessment of GUARDS instances. The goal is to assist the designers in making objective decisions for defining a specific instance of the generic architecture. After a short summary of the main architectural concepts of GUARDS, the paper describes the major assumptions concerning: i) component types (both hardware and software), ii) fault types, where special attention is paid to potentially correlated faults, and iii) the generic fault tolerance features of GUARDS. The main architectural characteristics of the target instances (one for each application domain) are briefly described. The modeling strategy is summarized and examples of models (stochastic Petri nets) are given. Selected results are then presented and discussed. They exemplify the usefulness of the modeling and evaluation method, in particular in the light of sensitivity analyses with respect to model parameters.
Modified Darcy''s Law, Fick''s Law, and Terzaghi''s Effective Stress Principle for Swelling Clay Soils
Authors: Lynn S. Bennethum, Marcio M. Murad, John H. Cushman
Venue:  (1997)

Governing equations often used in soil mechanics and hydrology include the classical Darcy''s law, Terzaghi''s effective stress principle, and the classical Fick''s first law. It is known that the classical forms of these relations apply only to non-swelling, granular materials. In this paper we summarize recent generalizations of these results for swelling porous media obtained using hybrid mixture theory by the authors. Hybrid mixture theory (HMT) is a methodical procedure for obtaining macroscopic constitutive restrictions which are thermodynamically admissible by exploiting the entropy inequality in the spirit of Coleman and Noll for spatially averaged properties. HMT applied to the modeling of swelling clay particles, viewed as clusters of adsorbed water and clay minerals, produces additional terms necessary to account for the physico-chemical forces between the adsorbed water and clay minerals, or more generally, for swelling colloids. New directions for modeling consolidation of swelling clays are proposed based on our view of clay particles as a two phase system
EFFICIENT VLSI IMPLEMENTATION OF A VLC DECODER FOR UNIVERSAL VARIABLE LENGTH CODE
Authors: Shang Xue, Bengt Oelmann
Venue: Proceedings of the IEEE Computer Society Annual Symposium on VLSI (ISVLSI'03) (2003)

Variable length code (VLC) is used in a large variety oflossless compression applications. A specially designedVLC, called "Universal Variable Length Code" (UVLC),is utilized in the latest video coding standard H.26L underdevelopment. In this work we develop an efficient decoderfor UVLC by utilizing the special properties of UVLCwhich perform coding in an alternating way (ALT). Wecompare the ALT decoder with the decoder called "VLCdecoder using plane separation" (PLS) which is claimedto be one of the most effective VLC decoders. Our resultsshow that the ALT decoder is 1.34 times faster, 1.7 timessmaller, and consumes 45% power in comparison to thePLS decoder.
Implementing Logic Programming Languages with Polymorphic Typing
Authors: Keehang Kwon, Gopalan Nadathur, Debra Wilson
Venue:  (1991)

\indent Extensions to the Warren Abstract Machine (WAM) are proposed for supporting polymorphic typing in logic programming. Typed logic programming languages require the use of {\em typed} unification and, as we argue, polymorphic typing forces some analysis of types at run-time. Much information about the structures of types is present at compile-time, and we show that using this information can considerably reduce the work during execution time. We consider two languages, one a version of Prolog with ML-like typing and another an order-sorted version, to show the generality of our ideas. We describe modified representations of terms, new instructions and additional data areas that in conjunction with existing WAM structures suffice to implement these languages. The nature of compiled code is illustrated through examples, and it is argued that minimal run-time overheads are incurred for processing types, especially in those cases where others have shown that type checking can be eliminated during execution.
An exact algorithm for the maximum leaf spanning tree problem
Authors: Tetsuya Fujie
Venue: Computers and Operations Research (2003)

Given a connected graph, the Maximum Leaf Spanning Tree Problem (MLSTP) is to find a spanning tree whose number of leaves (degree-one vertices) is maximum. We propose a branch-and-bound algorithm for MLSTP, in which an upper bound is obtained by solving a minimum spanning tree problem. We report computational results for randomly generated graphs and grid graphs with up to 100 vertices.
A Robust Parallel Architecture for Adaptive Color Quantization
Authors: Babu Mailachalam, T. Srikanthan
Venue: Proceedings of the The International Conference on Information Technology: Coding and Computing (ITCC'00) (2000)

Adaptive Color Quantization (ACQ) as described here is one method of color image compression employed for image storage and display in low cost monitors. Due to the nature of the palette based mapping employed in ACQ, it is prone to large errors due to noises introduced in transmission or additional lossy compression. This paper proposes a robust method of ACQ using a three-dimensional Self Organizing Map (3D SOM), which is tolerant to noises. The robustness of the 3D SOM is due to the property of such maps to cluster the color vectors in a topological manner. An efficient parallel architecture based on SIMD structure and parallel winner determination scheme, is presented for the implementation of the 3D SOM. The VLSI area-time efficiency of this parallel architecture over the current implementations is also established.
Classification of perfect linear codes with crown poset structure
Authors: Jungmin Ahn, Hyun Kwang Kim, Jung Soo Kim, Mina Kim
Venue: Discrete Mathematics (2003)

Brualdi et al. introduced the concept of poset codes. In this paper, we consider the problem of classifying all perfect linear codes when the set of coordinate positions is endowed with crown poset structure. We derive a Ramanujan-Nagell type diophantine equation which is satisfied by parameters of perfect linear P-code. Solving this equation, we characterize parameters of one and two error correcting perfect linear P-codes.
Data compression and encryption using cellular automata transforms
Authors: O. Lafe
Venue: Proceedings of the 1996 IEEE International Joint Symposia on Intelligence and Systems (1996)

A family of basis functions, generated from the evolving states of cellular automata (CA), is used to compress and encrypt data. The operations required in encoding and decoding the data are described under the umbrella cellular automata transforms (CAT). There is a huge number of these transform bases. CAT which can be used in the way other mathematical transforms (e.g. Fourier, Discrete Cosine, Laplace, Wavelet, etc.) are utilized. In data compression applications, the rules and pertinent keys used to generate the CA are selected in favour of those which yield basis functions with the best information packing characteristics. On the other hand, for encryption the selection is biased towards those with the tendency to yield an avalanche effect. In the latter case the transform process must be error free.
A Status Report on Research in Transparent Informed Prefetching
Authors: R. H Patterson, Garth A. Gibwson, Mahadev Satyanarayanan
Venue:  (1993)

This paper focuses on extending the power of caching and prefetching to reduce file read latencies by exploiting application level hints about future I/O accesses. We argue that systems that disclose high-level knowledge can transfer optimization information across module boundaries in a manner consistent with sound software engineering principles. Such Transparent Informed Prefetching (TIP) systems provide a technique for converting the high throughput of new technologies such as disk arrays and log-structured file systems into low latency for applications. Our preliminary experiments show that even without a high- throughput I/O subsystem TIP yields reduced execution time of up to 30% for applications obtaining data from a remote file server and up to 13% for applications obtaining data from a single local disk. These experiments indicate that greater performance benefits will be available when TIP is integrated with low level resource management policies and highly parallel I/O subsystems such as disk arrays.
Client/Server Qualities: A Basis for Reliable Distributed Workflow Management Systems
Authors: Hans Schuster, Stefan Jablonski, Christoph BuBler
Venue: Proceedings of the 17th International Conference on Distributed Computing Systems (ICDCS '97) (1997)

In distributed workflow management systems (WfMSs) many workflow servers and application programs referenced within workflows have to work together cooperatively. In this paper we introduce a middleware service for WfMSs which offers qualities for client/server communication. These qualities characterize the behavior of clients and servers in case of failure and recovery. Our middleware service builds an abstraction from the concrete implementation of a client/server interaction and hides characteristics of underlying system services, e.g. RPC mechanisms and TP monitors. For this reason, our middleware service supports the implementation of reliable distributed WfMSs.
Divide and conquer spot noise
Authors: Wim C. Leeuw, Robert Liere
Venue:  (1997)

The design and implementation of an interactive spot noise algorithm is presented. Spot noise is a technique which utilizes texture for the visualization of flow fields. Various design tradeoffs are discussed that allow an optimal implementation on a range of high end graphical workstations. Two applications are given: the steering of a smog prediction simulation and browsing a very large data set resulting from a direct numerical simulation of turbulence. These applications provide the motivation for the need of interactive visualization techniques.
Analysis of Internet multicast traffic performance considering multicast routing protocol
Authors: S. Uemo, T. Kato, K. Suzuki
Venue: Proceedings of the 2000 International Conference on Network Protocols (2000)

Recently audio and video delivery services are widely spread in the Internet. In order to deliver these data to multiple receivers at the same time, the multicast technologies are indispensable. In such a situation, the performance analysis of multicast traffic will be important in order to design and operate the Internet. Multicast traffic is controlled by its own routing protocol and the multicast routing protocol is more complex than conventional unicast routing protocols. In this paper we propose a new multicast performance analyzer considering distance vector multicast routing protocol (DVMRP) and protocol independent multicast-sparse mode (PIM-SM) routing protocols. It captures messages of a multicast routing protocol as well as multicast IP datagrams. It also analyzes DVMRP and PIM-SM messages in order to investigate the behaviors of multicast IP datagrams and measures the statistics of multicast traffic in detail. This paper describes the detailed design of the multicast performance analyzer and the results of analyzing multicast datagrams transmitted over networks.
Xml Web Services in the Organization
Authors: Chris Boar
Venue:  (2003)

:Discover how you can use XML-based Web services to dramatically improve the data sharing and communication capabilities in your organization. This guide teaches you how to exploit the interoperability features of the Microsoft.NET Framework to build highly available, platform-independent Web services. Easy-to-follow sample applications - downloadable from the companion Web site - demonstrate real-world solutions to common business problems that Web services can help resolve. As you work through these hands-on examples, you'll learn when a Web service will offer the best business solution - and get the guidance you need to integrate data exchange and communication with remote employees, partners, and customers.
Three-Dimensional Television, Video and Display Technology
Authors: Bahram Javidi
Venue:  (2002)

:Three-Dimensional Television, Video and Display Technology presents new advances in 3D TV and display techniques. It will discuss both theory and applications of these techniques. The theoretical concepts are illustrated by applied examples, numerical simulations, and experimental results. This is the first monograph of this rapidly evolving area of research and development. The book will be very useful for graduate students, scientists and engineers working in the field.
Locally Optimal Algorithms for Designing Schedules Based on Hopfield Networks
Authors: V. A. Kostenko, A. V. Vinokurov
Venue: Programming and Computing Software (2003)

Locally optimal algorithms for designing schedules for program execution on multiprocessors based on Hopfield networks are considered. Results of the numerical investigations of these algorithms are presented.
Static Restriction of the GOTO Statement
Authors: T. Bishop, M. Bodenstein, Richard W. Conway
Venue:  (1977)

NO SUPPLIED
Design and Implementation of a CAN / CAN Bridge
Venue: Proceedings of the 1996 International Symposium on Parallel Architectures, Algorithms and Networks (1996)

Distributed real-time control systems require a powerful communication link between remote subsystems. The Controller Area Network (CAN) was developed to support such applications. The CAN is a serial bus with high speed, high reliability, and low cost for distributed real time control applications. The CAN is a desirable, cheap solution for networks in industrial environments, but there is limit on the maximum length of a single CAN. A solution is to divide the CAN network into segments and connect them using bridges. Bridges are high performance devices that are used to interconnect LANs at the Logical Link Control (LLC) or Medium Access Control (MAC) level in the protocol hierarchy. Unlike many serial communication protocols the CAN message contains no information relating to the destination and source addresses. Because of this feature of the CAN message it is not possible to use traditional address based bridges to connect CAN segments. The aim of this study is to design and implement a bridge to connect CAN segments based on CAN protocol features.
The cones and foci proof technique for timed transition systems
Authors: Mark B. Zwaag
Venue:  (2000)

We propose an extension of the cones and foci proof technique that can be used to prove timed branching bisimilarity of states in timed transition systems. We prove the correctness of this technique and we give an example verification.
Choiceless polynomial time
Authors: Andreas Blass, Yuri Gurevich, Saharon Shelah
Venue:  (1997)

Turing machines define polynomial time (PTime) on strings but cannot deal with structures like graphs directly, and there is no known, easily computable string encoding of isomorphism classes of structures. Is there a computation model whose machines do not distinguish between isomorphic structures and compute exactly PTime properties? This question can be recast as follows: Does there exist a logic that captures polynomial time (without presuming the presence of a linear order)? Earlier, one of us conjectured the negative answer. The problem motivated a quest of stronger and stronger PTime logics. All these logics avoid arbitrary choice. Here we attempt to capture the choiceless fragment of PTime. Our computation model is a version of abstract state machines (formerly called evolving algebras). The idea is to replace arbitrary choice with parallel execution. The resulting logic is more expressive than other PTime logics in the literature. A more difficult theorem shows that the logic does not capture all PTime.