ppxscal/embedding_network huggingface dataset:
Performance characterization of forwarding strategies in personal communication networks
Authors: Ing-Ray Chen, Tsong-Min Chen, Chiang Lee
Venue: Proceedings of the 21st International Computer Software and Applications Conference (1997)

The paper presents a framework for modeling and evaluating the performance of forwarding strategies in a personal communication services (PCS) mobile network. A forwarding strategy in the PCS network can be implemented by two mechanisms: a forwarding operation which follows a chain of databases to locate a mobile user, and a resetting operation which updates the databases in the chain so that the current location of a mobile user can be known directly without having to follow a chain of databases. We consider the PCS network as a server whose function is to provide services to the mobile user for "updating the location of the user as the user moves across a database boundary" and "locating the mobile user". We use a Markov chain to describe the behavior of the mobile user and analyze the best time when forwarding and resetting should be performed in order to optimize the service rate of the PCS network. We demonstrate the applicability of our approach with hexagonal coverage models for the PCS network and provide a physical interpretation of the result.
Semantic Subtyping
Authors: Alain Frisch, Giuseppe Castagna, Véronique Benzaken
Venue: Proceedings of the 17th Annual IEEE Symposium on Logic in Computer Science (2002)

Usually subtyping relations are defined either syntactically by a formal system or semantically by an interpretation of types in an untyped denotational model. In this work we show how to define a subtyping relation semantically, for a language whose operationalsemantics is driven by types; we consider a rich type algebra, with product, arrow, recursive, intersection, union and complement types. Our approach is to "bootstrap" the subtyping relation through a notion of set-theoretic model of the type algebra.The advantages of the semantic approach are manifold. Foremost we get "for free" many properties (e.g., the transitivity of subtyping) that, with axiomatized subtyping, would require tedious and error prone proofs. Equally important is that the semantic approach allows one to derive complete algorithms for the subtyping relation or the propagation of types through patterns. As the subtyping relation has a natural (inasmuch as semantic) interpretation, the type system can give informative error messages when static type-checking fails. Last but not least the approach has an immediate impact in the definition and the implementation of languages manipulating XML documents, as this was our original motivation.
Creating a distributed factory object architecture
Authors: Sally M. Chan, Terence L. Lammers
Venue: Proceedings of the 1st International Conference on Enterprise Distributed Object Computing (1997)

The paper presents the development of a distributed architecture for the factory automation domain by applying the object-oriented domain engineering (OODE) method. The first part of the paper talks about extending formally defined object-oriented analysis and design (OOA&D) methods with domain engineering (DE) concepts. It defines the resulting OODE workflow, deliverables, and development cycle. The goal of the OODE workflow is to produce a generic object-oriented (OO) model, which spans a domain and from this model a domain framework for the rapid assembly of applications using a distributed object architecture. The second part of the paper presents case studies of OODE for two factory domain frameworks: machine monitoring system and data collection. The paper presents some findings on merging the two factory domain projects into an overall factory architecture. Then it concludes with a look at incorporating knowledge acquisition techniques to improve the OODE workflow.
Substructural Segmentation Based on Regional Shape Differences
Authors: Alexei M. C. Machado, James C. Gee, Mario F. M. Campos
Venue: Proceedings of the 15th Brazilian Symposium on Computer Graphics and Image Processing (2002)

This article presents a method for the segmentation of substructures based on exploratory factor analysis. In this approach, a set of high-dimensional shape-related variables is examined with the purpose of finding clusters with strong correlation. This clustering can potentially identify regions that have anatomic significance and thus lend insight to morphometric investigations. Methods: The information about regional shape is extracted by registering a reference image to a set of test images. Based on the displacement fields obtained from image registration, the amount of pointwise volume enlargement or reduction is computed and statistically analyzed with the purpose of extracting a reduced set of common factors. Experiments: The effectiveness and robustness of the method is demonstrated in a study of the human corpus callosum anatomy, based on a sample of 84 right-handed normal controls. Results: The method is able to partition the structure into regions of interest that present correlated shape variation. The confidence of results is evaluated by analyzing the statistical fit of the model.
Parallel implementation of ray-tracing algorithm on the Intel Delta parallel computer
Authors: Tong-Yee Lee, C. S. Raghavendra, John B. Nicholas
Venue: Proceedings of the 9th International Symposium on Parallel Processing (1995)

Ray tracing is one of the computer graphics techniques used to render high quality images. Ray tracing complex scenes can require large amounts of CPU time and memory storage. We present a parallel implementation of the ray tracing algorithm on the Intel Delta parallel computer. Two key issues of efficient implementation are load balancing and database distribution. In our database distribution, one part of the database is duplicated on each processor and the remaining part is evenly distributed among groups of processors. We balance load among processors by distributing subimages to processors in a global fashion based on previous workload requests.
Parallel Simulated Annealing: An Adaptive Approach
Authors: Jonas Knopman, Júlio S. Aude
Venue: Proceedings of the 11th International Symposium on Parallel Processing (1997)

This paper analyses alternatives for the parallelization of the Simulated Annealing algorithm when applied to the placement of modules in a VLSI circuit considering the use of PVM on an Ethernet cluster of workstations. It is shown that different parallelization approaches have to be used for high and low temperature values of the annealing process. The algorithm used for low temperatures is an adaptive version of the speculative algorithm proposed in the literature. Within this adaptive algorithm, the number of processors allocated to the solution of the placement problem and the number of moves evaluated per processor between synchronization points change with the temperature. At high temperatures, an algorithm based on the parallel evaluation of independent chains of moves has been adopted. It is shown that results with the same quality of those produced by the serial version can be obtained when shorter length chains are used in the parallel implementation.
An integrated microspacecraft avionics architecture using 3D multichip module building blocks
Authors: Leon Alkalai, Wai-Chi Fang
Venue: Proceedings of the 1996 International Conference on Computer Design, VLSI in Computers and Processors (1996)

In this paper, we describe current results from work in progress on the continued miniaturization of all spacecraft electronics into a single avionics system, using building-block elements. Each element is assumed to be a 'slice' within a stackable multichip module (MCM) 3D-architecture. The proposed architecture is new for the space community, but, is familiar to the commercial world. That is, we have proposed the use of only standard commercial interfaces for both the local (inter-slice) bus, inter-node system bus, and all the other interfaces for module testing and integration. Moreover, only commercially available programming languages, operating systems and software development environments are considered. The goal is to provide high levels of system reliability at a low cost. We plan to achieve this goal by applying hardware redundancy where necessary, and by maintaining a commercially compatible architecture that will achieve reliability through high volume production and mass usage. The first opportunity to validate the proposed spacecraft avionics system will be in July 1998 on-board the Deep-Space One asteroid-flyby mission. This will be the first in a series of high-tech missions within the New Millennium Program managed by the Jet propulsion Laboratory.
Efficient processor allocation for 3D tori
Authors: Wenjian Qiao, Lionel M. Ni
Venue: Proceedings of the 9th International Symposium on Parallel Processing (1995)

Efficient allocation of distinct subsets of processors to different jobs (i.e., space sharing) is critical to the performance of parallel computers, especially large scale parallel computers. This paper presents an efficient and lookahead strategy for processor allocation in 3D torus-connected systems, such as the Cray T3D, where each job requests for an exclusive allocation of a 3D submesh. The proposed processor allocation scheme has the following features: complete recognition of all maximal free submeshes, compact representation of submeshes, fairness with FCFS scheduling discipline, higher system utilization with lookahead scheduling, no restriction on the submesh orientation, and low allocation and scheduling overhead. The performance of the proposed strategy is demonstrated through simulation.
Parallel Implementation of Borvka's Minimum Spanning Tree Algorithm
Authors: Sun Chung, Anne Condon
Venue: Proceedings of the 10th International Parallel Processing Symposium (1996)

We study parallel algorithms for the minimum spanning tree problem, based on the sequential algorithm of Boruvka. The target architectures for our algorithm are asynchronous, distributed-memory machines. Analysis of our parallel algorithm, on a simple model that is reminiscent of the LogP model, shows that in principle a speedup proportional to the number of processors can be achieved, but that communication costs can be significant. To reduce these costs, we develop a new randomized linear work pointer jumping scheme that performs better than previous linear work algorithms. We also consider empirically the effects of data imbalance on the running time. For the graphs used in our experiments, load balancing schemes result in little improvement in running times. Our implementations on sparse graphs with 64,000 vertices on Thinking Machine's CM-5 achieve a speedup factor of about 4 on 16 processors. On this environment, packaging of messages turns out to be the most effective way to reduce communication costs.
TTP: Secure ACID Transfer Protocol for Electronic Ticket between Personal Tamper-Proof Devices
Authors: Kimio Kuramitsu, Tadashi Murakami, Hajime Matsuda, Ken Sakamura
Venue: 24th International Computer Software and Applications Conference (2000)

The wide-spreading markets of digital content increase the demand to transfer electronic value through open networks. This paper designs Ticket Transfer Protocol (TTP), which enables electronic transferable tickets to directly move between two personal tamper-proof devices. The applied two-phase commit protocol into the transfer realizes the ACID transaction without any external coordinators. Moreover, this paper addressed the initial implementation of secure TTP, enabling the detection of message replays by attackers, and evaluated the size of its logging field in the transaction. We conclude that TTP has enough reliability to transfer electronic tickets directly between personal ticket wallets.
On the Efficiency of Reductions in µ-SIMD Media Extensions
Authors: Jesus Corbal, Roger Espasa, Mateo Valero
Venue: Proceedings of the 2001 International Conference on Parallel Architectures and Compilation Techniques (2001)

Abstract: Many important multimedia applications contain a significant fraction of reduction operations. Although, in general, multimedia applications are characterized for having high amounts of Data Level Parallelism, reductions and accumulations are difficult to parallelize and show a poor tolerance to increases in the latency of the instructions. This is specially significant for µ-SIMD extensions such as MMX or AltiVec. To overcome the problem of reductions in µ-SIMD ISAs, designers tend to include more and more complex instructions able to deal with the most common forms of reductions in multimedia. As long as the number of processor pipeline stages grows, the number of cycles needed to execute these multimedia instructions increases with every processor generation, severely compromising performance. This paper presents an in-depth discussion of how reductions/accumulations are performed in current µ-SIMD architectures and evaluates the performance trade-offs for a near-future highly aggressive superscalar processors with three different styles of µ-SIMD extensions. We compare a MMX-like alternative to a MDMX-like extension that has Packed accumulators to attack the reduction problem, and we also compare it to MOM, a matrix register ISA. We will show that while packed accumulators present several advantages, they introduce artificial recurrences that severely degrade performance for processors with high number of registers and long latency operations. On the other hand, this paper demonstrates that longer SIMD media extensions such as MOM can take great advantage of accumulators by exploiting the associative parallelism implicit in reductions.
The Paderborn University BSP (PUB) Library - Design, Implementation and Performance
Authors: Olaf Bonorden, Ben H. H. Juurlink, Ingo von Otte, Ingo Rieping
Venue: Proceedings of the 13th International Symposium on Parallel Processing and the 10th Symposium on Parallel and Distributed Processing (1999)

The Paderborn University BSP (PUB) library is a parallel C library based on the BSP model. The basic library supports buffered and unbuffered asynchronous communication between any pair of processors, and a mechanism for synchronizing the processors in a barrier style. In addition, it provides routines for collective communication on arbitrary subsets of processors, partition operations, and a zero-cost synchronization mechanism. Furthermore, some techniques used in its implementation deviate significantly from the techniques used in other BSP libraries.
Relative Performance of Hardware and Software-Only Directory Protocols Under Latency Tolerating and Reducing Techniques
Authors: Håkan Grahn, Per Stenström
Venue: Proceedings of the 11th International Symposium on Parallel Processing (1997)

In both hardware-only and software-only directory protocols the performance is often limited by memory access stall times. To increase the performance, several latency tolerating and reducing techniques have been proposed and shown effective for hardware-only directory protocols. For software-only directory protocols, the efficiency of a technique depends not only on how effective it is as seen by the local processor, but also on how it impacts the software handler execution overhead in the node where a memory block is allocated.Based on architectural simulations and case studies of three techniques, we find that prefetching can degrade the performance of software-only directory protocols due to useless prefetches. A relaxed memory consistency model hides all write latency for software-only directory protocols, but the software handler overhead is virtually unaffected and now constitutes a larger portion of the execution time. Overall, latency tolerating techniques for software-only directory protocols must be chosen with more care than for hardware-only directory protocols.
Color Image Gradients for Morphological Segmentation
Authors: Roberto Hirata,  Jr., Franklin César Flores, Junior Barrera, Roberto de Alencar Lotufo, Fernand Meyer
Venue: Proceedings of the 13th Brazilian Symposium on Computer Graphics and Image Processing (2000)

This paper proposes an approach for color segmentation which is an alternative to the search of a total order in the color space. Instead of looking for a total order, we look for a suitable metric that defines a color gradient, which is a fundamental step of the morphological segmentation paradigm.
Using Object-Oriented Principles to Optimize Update Propagation to Materialized Views
Authors: Harumi A. Kuno, Elke A. Rundensteiner
Venue: Proceedings of the Twelfth International Conference on Data Engineering (1996)

View materialization is known to be a valuable technique for performance optimization in relational databases, and much work has been done addressing the problem of consistently maintaining relational views under update operations. However, little progress has been made thus far regarding the topic of view materialization in object-oriented databases (OODBs). In this paper, we demonstrate that there are several significant differences between the relational and object-oriented paradigms that can be exploited when addressing the object-oriented view materialization problem. We can use the subsumption relationships between classes to identify branches of classes to which we do not need to propagate updates. Similarly, we can use encapsulated interfaces combined with the fact that any unique database property is inherited from a single location to provide a ``registration/notification'' service for optimizing incremental view updates. We have successfully implemented all proposed techniques in the MultiView system, which provides updatable materialized classes and virtual schemata on top of the GemStone OODBMS. We also report results from the experimental studies we have run on the MultiView system measuring the impact of various optimization strategies incorporated into our materialization update algorithms.
CMAR: Accurate and Efficient Classification Based on Multiple Class-Association Rules
Authors: Wenmin Li, Jiawei Han, Jian Pei
Venue: Proceedings of the 2001 IEEE International Conference on Data Mining (2001)

Previous studies propose that associative classification has high classification accuracy and strong flexibility at handling unstructured data. However, it still suffers from the huge set of mined rules and sometimes biased classification or overfitting since the classificationis based on only single high-confidence rule. In this study, we propose new associative classification method, CMAR, i.e., Classification based on Multiple Association Rules. The method extends an efficient frequent pattern mining method, FP-growth ,constructs classdistribution-associated FP-tree, and mines large database efficiently. Moreover, it applies CR-tree structure to store and retrieve mined association rulesefficiently, and prunes rules effectively based on confidence, correlation and database coverage. The classification is performed based on weighted X2 analysis using multiple strong association rules. Our extensive experiments on 26 databases from UCI machine learning database repository show that CMAR is consistent, highly effective at classificationof various kinds of databases and has better average classificationaccuracy in comparison with CBA and C4.5.Moreover,our performancestudy shows that the method is highly efficient and scalable in comparison with other reported associative classification methods.
SSDT: A Scalable Subspace-Splitting Classifier for Biased Data
Authors: Haixun Wang, Philip S. Yu
Venue: Proceedings of the 2001 IEEE International Conference on Data Mining (2001)

Decision trees are one of the most extensively used data mining models. Recently, a number of efficient, scalable algorithms for constructing decision trees on large disk-resident dataset have been introduced. In this paper, we study the problem of learning scalable decision trees from datasets with biased class distribution. Our objective is to build decision trees that are ore concise and oreinterpretable while maintaining the scalability of the model.To achieve this, our approach searches for subspace clusters of data cases of the biased class to enable multivariate splittings based on weighted distances to such clusters. In orderto build concise and interpretable models, other approaches including multivariate decision trees and association rules, often introduce scalability and performance issues. The SSDT algorithm we present achieves the objective without loss in efficiency, scalability, and accuracy.
View Caching: Efficient Software Shared Memory for Dynamic Computations
Authors: Vijay Karamcheti, Andrew A. Chien
Venue: Proceedings of the 11th International Symposium on Parallel Processing (1997)

Software distributed shared memory (DSM) techniques, while effective on applications with coarse-grained sharing, yield poor performance for the fine-grained sharing encountered in applications increasingly relying on sophisticated adaptive and hierarchical algorithms. Such applications exhibit irregular communication patterns unsynchronized with computation, incurring large overheads for synchronous (request-reply) DSM protocols that require responsive processing of coherence messages. We describe a new DSM framework, View Caching, that addresses this problem by utilizing application knowledge of data access semantics to enable the construction of low-overhead, asynchronous coherence protocols. Experiments on the Cray T3D show that view caching enables efficient execution of fine-grained irregular applications, reducing both coherence overheads and idle time to improve performance by up to 35% over a weakly-consistent DSM implementation.
A visualization-based environment for top-down debugging of parallel programs
Authors: Joseph L. Sharnowski, Betty H. C. Cheng
Venue: Proceedings of the 9th International Symposium on Parallel Processing (1995)

This paper describes a parallel debugging environment that applies visualizations in a top-down, structured approach for debugging. This environment, referred to as GOLD, uses visualization in the traditional way for examining a program state, but it also extends the use of visualizations in two directions. First, a technique is described for using visualizations to guide the operation of setting a causal distributed breakpoint for a set of processes. Second, a strategy is introduced for coordinating the use of different types of visualization when examining a program state.
Successful Software Applications: Can They Be Evaluated?
Authors: Chris E. Hillam, Helen M. Edwards, Caroline L. Young
Venue: 24th International Computer Software and Applications Conference (2000)

There is extensive literature highlighting the difficulty in evaluating the success of software applications, and even in defining the meaning of the term ¿success¿. Two complementary studies are presented that have focused on this from different perspectives (in the context of small-medium organizations (SMOs) in terms of (i) return on investment and (ii) user satisfaction. The former has adopted case study analysis, the latter longitudinal surveys as the instruments used: illustrative results are provided for both approaches. Results indicate that within the first case study company there is a strong link between the identified company strategy typology and the attitude to the type of investment undertaken. The preliminary results from the second case indicate that, contrary to received wisdom, user satisfaction with systems can exist despite a lack of liaison between developers and users in the requirements phase. Other factors that have influenced this satisfaction are outlined.