ppxscal/embedding_network huggingface dataset:
Complexity and Fast Algorithms for Multiexponentiations
Authors: Vassil S. Dimitrov, Graham A. Jullien, William C. Miller
Venue: IEEE Transactions on Computers (2000)

In this paper, we propose new algorithms for multiple modular exponentiation operations. The major aim of these algorithms is to speed up the performance of some cryptographic protocols based on multiexponentiation. Our new algorithms are based on binary-like complex arithmetic, introduced by Pekmestzi and generalized in this paper.
Statistical estimators for relational algebra expressions
Authors: Wen-Chi Hou, Gultekin Ozsoyoglu, Baldeo K. Taneja
Venue: Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1988)

Present database systems process all the data related to a query before giving out responses. As a result, the size of the data to be processed becomes excessive for real-time/time-constrained environments. A new methodology is needed to cut down systematically the time to process the data involved in processing the query. To this end, we propose to use data samples and construct an approximate synthetic response to a given query. In this paper, we consider only COUNT(E) type queries, where E is an arbitrary relational algebra expression. We make no assumptions about the distribution of attribute values and ordering of tuples in the input relations, and propose consistent and unbiased estimators for arbitrary COUNT(E) type queries. We design a sampling plan based on the cluster sampling method to improve the utilization of sampled data and to reduce the cost of sampling. We also evaluate the performance of the proposed estimators.
An empirical study of conservative scheduling
Authors: Ha Yoon Song, Richard A. Meyer, Rajive Bagrodia
Venue: Proceedings of the fourteenth workshop on Parallel and distributed simulation (2000)

It is well known that the critical path provides an absolute lower bound on the execution time of a conservative parallel discrete event simulation. It stands to reason that optimal execution time can only be achieved by immediately executing each event on the critical path. However, dynamically identifying the critical event is difficult, if not impossible. In this paper, we examine several heuristics that might help to determine the critical event, and conduct a performance study to determine the effectiveness of using these heuristics for preferential scheduling.
Topological Numbers and Singularities in Scalar Images: Scale-Space Evolution Properties
Authors: Stiliyan N. Kalitzin, Bart M. Ter Haar Romeny, Alfons H. Salden, Peter Fm Nacken, Max A. Viergever
Venue: Journal of Mathematical Imaging and Vision (1998)

Singular points of scalar images in any dimensions are classified by a topological number. This number takes integer values and can efficiently be computed as a surface integral on any closed hypersurface surrounding a given point. A nonzero value of the topological number indicates that in the corresponding point the gradient field vanishes, so the point is singular. The value of the topological number classifies the singularity and extends the notion of local minima and maxima in one-dimensional signals to the higher dimensional scalar images. Topological numbers are preserved along the drift of nondegenerate singular points induced by any smooth image deformation. When interactions such as annihilations, creations or scatter of singular points occurs upon a smooth image deformation, the total topological number remains the same.Our analysis based on an integral method and thus is a nonperturbative extension of the order-by-order approach using sets of differential invariants for studying singular points.Examples of typical singularities in one- and two-dimensional images are presented and their evolution induced by isotropic linear diffusion of the image is studied.
Photorealistic Scene Reconstruction by Voxel Coloring
Authors: Steven M. Seitz, Charles R. Dyer
Venue: International Journal of Computer Vision (1999)

A novel scene reconstruction technique is presented, different from previous approaches in its ability to cope with large changes in visibility and its modeling of intrinsic scene color and texture information. The method avoids image correspondence problems by working in a discretized scene space whose voxels are traversed in a fixed visibility ordering. This strategy takes full account of occlusions and allows the input cameras to be far apart and widely distributed about the environment. The algorithm identifies a special set of invariant voxels which together form a spatial and photometric reconstruction of the scene, fully consistent with the input images. The approach is evaluated with images from both inward-facing and outward-facing cameras.
Processor Scheduling and Allocation for 3D Torus Multicomputer Systems
Authors: Hyunseung Choo, Seong-Moo Yoo, Hee Yong Youn
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

Multicomputer systems achieve high performance by utilizing a number of computing nodes. Recently, by achieving significant reductions in communication delay, the three-dimensional (3D) torus has emerged as a new candidate interconnection topology for message-passing multicomputer systems. In this paper, we propose an efficient processor allocation scheme¿scan search scheme¿for the 3D torus based on a first-fit approach. The scan search scheme minimizes the average allocation time for an incoming task by effectively manipulating the 3D information on a torus as 2D information using a data structure called the CST (Coverage Status Table). Comprehensive computer simulation reveals that the allocation time of the scan search scheme is always smaller than that of the earlier scheme based on a best-fit approach. The difference gets larger as the input load increases, and it is as much a factor of 3 for high load. To investigate the performance of the proposed scheme in different scheduling environments, we also consider a non-FCFS scheduling policy along with the typical FCFS policy. The allocation time complexity of the scan search scheme is $O(LW^{2}H^{2})$. This is significantly smaller than that of the existing scheme which is $O(L^{4}W^{4}H^{4})$. Here, $L$, $W$, and $H$ represent the length, width, and height of 3D torus, respectively.
Automatic Methods for Hiding Latency in Parallel and Distributed Computation
Authors: Matthew Andrews, Tom Leighton, P. Takis Metaxas, Lisa Zhang
Venue: SIAM Journal on Computing (1999)

In this paper we describe methods for mitigating the degradation in performance caused by high latencies in parallel and distributed networks. For example, given any "dataflow" type of algorithm that runs in T steps on an n-node ring with unit link delays, we show how to run the algorithm in O(T) steps on any n-node bounded-degree connected network with average link delay O(1). This is a significant improvement over prior approaches to latency hiding, which require slowdowns proportional to the maximum link delay. In the case when the network has average link delay $\dave$, our simulation runs in $O(\sqrt{\dave} T)$ steps using $n/\sqrt{\dave}$ processors, thereby preserving efficiency. We also show how to efficiently simulate an n X n array with unit link delays using slowdown $\tilde O(\dave^{2/3})$ on a two-dimensional array with average link delay $\dave$. Last, we present results for the case in which large local databases are involved in the computation.
A Theory-Based Representation for Object-Oriented Domain Models
Authors: Scott D. DeLoach, Thomas C. Hartrum
Venue: IEEE Transactions on Software Engineering (2000)

Formal software specification has long been touted as a way to increase the quality and reliability of software; however, it remains an intricate, manually intensive activity. An alternative to using formal specifications directly is to translate graphically based, semiformal specifications into formal specifications. However, before this translation can take place, a formal definition of basic object-oriented concepts must be found. This paper presents an algebraic model of object-orientation that defines how object-oriented concepts can be represented algebraically using an object-oriented algebraic specification language O-Slang. O-Slang combines basic algebraic specification constructs with category theory operations to capture internal object class structure, as well as relationships between classes.
SERF: ODMG-based generic re-structuring facility
Authors: E. A. Rundensteiner, K. Claypool, M. Li, L. Chen, Z. Zhang, C. Natarajan, J. Jin, S. De Lima, S. Weiner
Venue: Proceedings of the 1999 ACM SIGMOD international conference on Management of data (1999)

The age of information management and with it the advent of increasingly sophisticated technologies have kindled a need in the database community and others to re-structure existing systems and move forward to make use of these new technologies. Legacy application systems are being transformed to newer state-of-the-art systems, information sources are being mapped from one data model to another, a diversity of data sources are being transformed to load, cleanse and consolidate data into modern data-warehouses [CR99]. Re-structuring is thus a critical task for a variety of applications. For this reason, most object-oriented database systems (OODB) today support some form of re-structuring support [Tec94, Obj93, BKKK87]. This existing support of current OODBs [BKKK87, Tec94, Obj93] is limited to a pre-defined taxonomy of simple fixed-semantic schema evolution operations. However, such simple changes, typically to individual types only, are not sufficient for many advanced applications [Br&eacute;96]. More radical changes, such as combining two types of redefining the relationship between two types, are either very difficult or even impossible to achieve with current commercial database technology [Tec94, Obj93]. In fact, most OODBs would typically require the user to write ad-hoc programs to accomplish such transformations. Research that has begun to look into the issue of complex changes [Br&eacute;96, Ler96] is still limited by providing a fixed set of some selected (even if now more complex) operations. To address these limitations of the current restructuring technology, we have proposed the SERF framework which aims at providing a rich environment for doing complex user-defined transformations flexibly, easily and correctly [CJR98b]. The goal of our work is to increase the usability and utility of the SERF framework and its applicability to re-structuring problems beyond OODB evolution. Towards that end, we provide re-usable transformations via the notion of SERF Templates that can be packaged into libraries, thereby increasing the portability of these transformations. We also now have a first cut at providing an assurance of consistency for the users of this system, a semantic optimizer that provides some performance improvements via enhanced query optimization techniques with emphasis on the re-structuring primitives [CNR99]. In this demo we give an overview of the SERF framework, its current status and the enhancements that are planned for the future. We also present an example of the application of SERF to a domain other than schema evolution, i.e., the web restructuring.
Robust Descriptors of Binary Shapes with Applications
Authors: E. De Ves, M. E. Díaz, G. Ayala, J. Domingo, A. Simó
Venue: International Journal of Computer Vision (1999)

The subject of this paper is to propose and test a set of numerical descriptors of 2D binary planar shapes. Given a shape, A, the transformations of A with a given mathematical morphological operation and different structuring elements are considered. The measures of this family of transformed sets provide a numerical description of the original set A.These descriptors are very robust against noise and maintain a reasonable discriminatory power. The robustness against different levels of contour degradation is tested by simulation. Starting with a clean (without noise) set, &Lgr;, it is assumed that the observed set, A, is a noisy version (with contour degradation) of &Lgr;.The performance of the descriptors, when they are used to compare different shapes or shapes from a scene with models, is studied and compared with related descriptors based on the granulometric analysis of the original set, which are the closest previous alternative to our approach in the literature.
Programming World Wide Web pages in scheme
Authors: Kurt Nørmark
Venue: ACM SIGPLAN Notices (1999)

In this paper we will argue that pages on the World Wide Web can be made directly as programs in a functional programming language instead of through HTML or an HTML-based authoring tool. We use the Scheme programming language from the Lisp family for WWW page production. It is concluded that a Lisp language is an attractive direct vehicle for authoring of Internet material in the sense that the source of a WWW document becomes a Lisp program. Abstraction from details in the underlying markup language constitutes the main advantage in our approach. This is consistent with the expected advantage of introducing XML as a successor of HTML. In addition we find it useful to have the power of a high quality programming language available for automation of routine tasks during the authoring process.
Deeper Sparsely Nets can be Optimal
Authors: Valeriu Beiu, Hanna E. Makaruk
Venue: Neural Processing Letters (1998)

The starting points of this paper are two size-optimal solutions: (i) one for implementing arbitrary Boolean functions [1]; and (ii) another one for implementing certain sub-classes of Boolean functions [2]. Because VLSI implementations do not cope well with highly interconnected nets &ndash; the area of a chip grows with the cube of the fan-in [3] &ndash; this paper will analyse the influence of limited fan-in on the size optimality for the two solutions mentioned. First, we will extend a result from Horne Hush [1] valid for fan-ins &Dgr; = 2 to arbitrary fan-in. Second, we will prove that size-optimal solutions are obtained for small constant fan-in for both constructions, while relative minimum size solutions can be obtained for fan-ins strictly lower than linear. These results are in agreement with similar ones proving that for small constant fan-ins (&Dgr; = 6 ... 9), there exist VLSI-optimal (i.e., minimising AT2) solutions [4], while there are similar small constants relating to our capacity of processing information [5].
Profile-driven code execution for low power dissipation (poster session)
Authors: Diana Marculescu
Venue: Proceedings of the 2000 international symposium on Low power electronics and design (2000)

This paper proposes a novel technique for power-performance trade-off based on profile-driven code execution. Specifically, we show that there is an optimal level of parallelism for energy consumption and propose a compiler-assisted technique for code annotation that can be used at run-time to adaptively trade-off power and performance. As shown by experimental results, our approach is up to 23% better than clock throttling and is as efficient as voltage scaling (up to 10% better in some cases). The technique proposed in this paper can be used by an ACPI-compliant power manager for prolonging battery life or as a passive cooling feature for thermal management.
Co-Synthesis to a Hybrid RISC/FPGA Architecture
Authors: Maya B. Gokhale, Janice M. Stone, Edson Gomersall
Venue: Journal of VLSI Signal Processing Systems (2000)

Hybrid architectures combining conventional processors with configurable logic resources enable efficient coordination of control with datapath computation. With integration of the two components on a single device, housekeeping tasks and, optionally, loop control and data-dependent branching, can be handled by the conventional processor, while regular datapath computation occurs on the configurable hardware. This paper describes a novel approach to programming such hybrid devices that gives the programmer control over mapping of data and computation between conventional processor and configurable logic. With a simple set of pragma and intrinsic function directives, the NAPA C language provides for manual control over perhaps the most important aspect of programming such hybrid devices. Alternatively, as experience is gained about tradeoffs between the two computational resources, mapping directives may eventually be generated by an external tool. The paper further describes a research prototype compiler that targets the hybrid processor model, with a concrete implementation for the National Semiconductor NAPA1000 chip. The NAPA C compiler parses the mapping directives, performs semantic analysis, and co-synthesizes a conventional processor executable combined with a configuration bit stream for the configurable logic. Two major compiler phases, the synthesis of pipelined loops and the datapath synthesis, are described in detail.
Formal Value-Range and Variable Testability Techniquesfor High-Level Design-For-Testability
Authors: Sandhya Seshadri, Michael S. Hsiao
Venue: Journal of Electronic Testing: Theory and Applications (2000)

This research applies formal dataflow analysis and techniques to high-level DFT. Our proposed approach improves testability of the behavioral-level circuit description (such as in VHDL) based on propagation of the value ranges of variables through the circuit's Control-Data Flow Graph (CDFG). The resulting testable circuit is accomplished via controllability and observability computations from these value ranges and insertion of appropriate testability enhancements, while keeping the design area-performance overhead to a minimum.
Evaluating the Outcome of Two Teaching Methods of Breath Actuated Inhaler in an Inner City Asthma Clinic
Authors: Robert J. Rydman, Kathy Sonenthal, Lakshminarayana Tadimeti, Nikolai Butki, Michael F. McDermott
Venue: Journal of Medical Systems (1999)

Objectives: Our objective was to compare two different teaching methods used to educate patients in the use of a breath actuated inhaler (BAI) and to assess the impact of its continued use on their metered-dose inhaler (MDI) technique. Design: Prospective, randomized, controlled trial. Setting: Adult Pulmonary/Asthma clinic of Cook County Hospital, Chicago, IL. Patients: Diagnosed, stable asthmatics. Intervention: The patients were randomized into two groups. The experimental group received verbal instructions and demonstration on breath actuated inhaler technique while the control group received written instructions only on BAI use. The metered dose inhaler technique of both groups of patients was also evaluated. Measures: A checklist evaluating the key aspects of proper BAI and MDI inhalation techniques was used to assess the use of both types of inhalers at entry into the study and upon postintervention follow-up at 8 to 20 weeks. Results: At baseline, 97% of patients in the experimental group and 83% of patients in the control group were initially able to demonstrate BAI inhalation technique correctly. Upon follow-up, 82% of the control group and 68% of the experimental group were able to use the BAI correctly, which was a statistically significant deterioration in the experimental group. In both of these groups, there was a statistically significant improvement in MDI technique. Conclusions: Written instructions alone may be an adequate teaching tool for proper inhalation technique of BAI. Continued BAI use appears not to impact adversely on proper MDI technique.
Optimizing for reduced code space using genetic algorithms
Authors: Keith D. Cooper, Philip J. Schielke, Devika Subramanian
Venue: Proceedings of the ACM SIGPLAN 1999 workshop on Languages, compilers, and tools for embedded systems (1999)

Code space is a critical issue facing designers of software for embedded systems. Many traditional compiler optimizations are designed to reduce the execution time of compiled code, but not necessarily the size of the compiled code. Further, different results can be achieved by running some optimizations more than once and changing the order in which optimizations are applied. Register allocation only complicates matters, as the interactions between different optimizations can cause more spill code to be generated. The compiler for embedded systems, then, must take care to use the best sequence of optimizations to minimize code space.Since much of the code for embedded systems is compiled once and then burned into ROM, the software designer will often tolerate much longer compile times in the hope of reducing the size of the compiled code. We take advantage of this by using a genetic algorithm to find optimization sequences that generate small object codes. The solutions generated by this algorithm are compared to solutions found using a fixed optimization sequence and solutions found by testing random optimization sequences. Based on the results found by the genetic algorithm, a new fixed sequence is developed to reduce code size. Finally, we explore the idea of using different optimization sequences for different modules and functions of the same program.
Serialization graph algorithms for multiversion concurrency control
Authors: Thanasis Hadzilacos
Venue: Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1988)

We propose a new algorithmic framework for database concurrency control using multiple versions of data items and a serialization graph of the transactions as a synchronization technique, which generalizes all concurrency control methods known so far. This class of algorithms, called MVSGA for Multi Version Serialization Graph set of Algorithms, works by monitoring the acyclicity of the serialization graph which has nodes corresponding to transactions and arcs corresponding to read-from and other transaction positioning decisions made by the scheduler. For each of the major known schedulers we give examples of MVSGA schedulers that cover them. We propose a criterion for optimality among MVSGA schedulers Choice of versions to read from and relative positioning of transactions in the serialization graph should be done in a way that leaves the largest flexibility possible for future choices. This flexibility is measured as the number of pairs of nodes in the serialization graph that remain incomparable. Unfortunately, enforcing this criterion turns out to be NP-complete, so we describe an MVSGA scheduler based on a heuristic that approximates the optimal.
Network restoration using recurrent neural networks
Authors: G. Prem Kumar P. Prem Venkataram
Venue: International Journal of Network Management (1998)

In this article, a method is proposed for network restoration using a centralized, static restoration after failure, where the restoration initiated at the local node or at the source uses a hybrid strategy. &copy; 1998 John Wiley & Sons, Ltd.
Collaborative filtering to locate, comprehend, and organize collections of Web sites
Authors: Loren Terveen, Will Hill, Brian Amento
Venue: ACM SIGART Bulletin (1998)

Finding information is a common and fundamental task for Internet users. Search engines such as AltaVista and indices such as Yahoo! are the tools commonly used for this task. Users type in queries using keywords to indicate their interest or navigate through hierarchical directories of topics, eventually obtaining (usually quite large) collections of Web pages.