ppxscal/embedding_network huggingface dataset:
2007 Special Issue: Edge of chaos and prediction of computational performance for neural circuit models
Authors: Robert Legenstein, Wolfgang Maass
Venue: Neural Networks (2007)

We analyze in this article the significance of the edge of chaos for real-time computations in neural microcircuit models consisting of spiking neurons and dynamic synapses. We find that the edge of chaos predicts quite well those values of circuit parameters that yield maximal computational performance. But obviously it makes no prediction of their computational performance for other parameter values. Therefore, we propose a new method for predicting the computational performance of neural microcircuit models. The new measure estimates directly the kernel property and the generalization capability of a neural microcircuit. We validate the proposed measure by comparing its prediction with direct evaluations of the computational performance of various neural microcircuit models. The proposed method also allows us to quantify differences in the computational performance and generalization capability of neural circuits in different dynamic regimes (UP- and DOWN-states) that have been demonstrated through intracellular recordings in vivo.
HACC: an architecture for cluster-based web servers
Authors: Xiaolan Zhang, Michael Barrientos, J. Bradley Chen, Margo Seltzer
Venue: Proceedings of the 3rd conference on USENIX Windows NT Symposium - Volume 3 (1999)

This paper presents the design, implementation, and performance of the Harvard Array of Clustered Computers (HACC), a cluster-based design for scalable, cost-effective web servers. HACC is designed for locality enhancement. Requests that arrive at the cluster are distributed among the nodes so as to enhance the locality of reference that occurs on individual nodes in the cluster. By improving locality on individual cluster nodes, we can reduce their working set sizes and achieve superior performance for less cost than conventional approaches. We implemented HACC on Windows NT 4.0 and evaluated its performance for both static documents and workloads of dynamically generated documents adapted from logs of commercial web servers. Our performance results show that HACC's locality enhancement can improve performance by up to 121% for our stochastically generated static file case, by up to 40% for our trace-based static file case, and by up to 52% for our trace-based dynamic document case, compared to an IP-Sprayer approach to building cluster-based web servers.
Estimation of the parameters of a bilinear model with applications to submarine detection and system identification
Authors: Richard Abrahamsson, Steven M. Kay, Petre Stoica
Venue: Digital Signal Processing (2007)

In this work we study the problem of estimating the parameters of a bilinear model describing, e.g., the amplitude modulation of extremely low frequency electromagnetic (ELFE) signatures of submarines. A similar problem arises in estimation of a nonlinear dynamic system using a Hammerstein-Wiener model, where two nonlinear static blocks surround a linear dynamic block. For these purposes a new method is derived. It is also shown in the same context that a two-stage method for parameter estimation of Hammerstein-Wiener models can be interpreted as an approximate least squares method. We also show the similarities with the problem of weighted low-rank approximation and the fact that these problems can be solved exactly in finite time using solvers for global optimization of systems of polynomials based on self dual optimization.
Time Domain Simulation Technique of a Power System Transient with VSC Based Facts Devices
Authors: P. Kumkratug, P. Laohachai
Venue: Proceedings of the First Asia International Conference on Modelling & Simulation (2007)

This paper proposes the simulation technique of power system with voltage source converter (VSC) based FACTS devices. The benefits of the simulation method on the stability are explored by incorporation the load injection model of various VSCs into the power system. The paper presents the method of simulation the power system with VSC on MATLAB/SIMULINK. The proposed method of simulation is tested on the new England system.
The Brain Locus of Interaction between Number and Size: A Combined Functional Magnetic Resonance Imaging and Event-related Potential Study
Authors: Roi Cohen Kadosh, Kathrin Cohen Kadosh, David E. J. Linden, Wim Gevers, Andrea Berger, Avishai Henik
Venue: Journal of Cognitive Neuroscience (2007)

Whether the human brain is equipped with a special neural substrate for numbers, or rather with a common neural substrate for processing of several types of magnitudes, has been the topic of a long-standing debate. The present study addressed this question by using functional magnetic resonance imaging (fMRI) and event-related potentials (ERPs) together with the size-congruity paradigm, a Stroop-like task in which numerical values and physical sizes were varied independently. In the fMRI experiment, a region-of-interest analysis of the primary motor cortex revealed interference effects in the hemisphere ipsilateral to the response hand, indicating that the stimulus-stimulus conflict between numerical and physical magnitude is not completely resolved until response initiation. This result supports the assumption of distinct comparison mechanisms for physical size and numerical value. In the ERP experiment, the cognitive load was manipulated in order to probe the degree to which information processing is shared across cognitive systems. As in the fMRI experiment, we found that the stimulus-stimulus conflict between numerical and physical magnitude is not completely resolved until response initiation. However, such late interaction was found only in the low cognitive load condition. In contrast, in the high load condition, physical and numerical dimensions interacted only at the comparison stage. We concluded that the processing of magnitude can be subserved by shared or distinct neural substrates, depending on task requirements.
Evolutionary adaptive-critic methods for reinforcement learning
Authors: Xin Xu, Han-gen He, Dewen Hu
Venue: Proceedings of the Evolutionary Computation on 2002. CEC '02. Proceedings of the 2002 Congress - Volume 02 (2002)

In this paper, a novel hybrid learning method is proposed for reinforcement learning problems with continuous state and action spaces. The reinforcement learning problems are modeled as Markov decision processes (MDPs) and the hybrid learning method combines evolutionary algorithms with gradient-based adaptive heuristic critic (AHC) algorithms to approximate the optimal policy of MDPs. The suggested method takes the advantages of evolutionary learning and gradient-based reinforcement learning to solve reinforcement learning problems. Simulation results on the learning control of an acrobot illustrate the efficiency of the presented method.
An algebraic generalization of subelliptic multipliers
Authors: John P. D'Angelo
Venue:  (2006)

In this thesis, we are primarily concerned with an algorithm, due to Kohn, for finding subelliptic multipliers in the theory of several complex variables. Kohn's work applies to rings of germs of smooth functions. A special case of it leads to an interesting algebraic procedure defined for the ring of convergent power series with complex coefficients. We modify this procedure by extending it to more general regular local rings. To do so, we define two nonlinear operations between the set of modules of 1-forms and the set of ideals, and we alternatively apply these operations to a given initial module of 1-forms to obtain an increasing sequence of modules of 1-forms. In case that a regular local ring satisfies the weak Jacobian condition at the maximal ideal over a quasi-coefficient field of characteristic zero, we construct subelliptic multipliers for a submodule of the universally finite module of differentials on the given ring. In particular we provide an unusual process for determining whether an ideal is primary to the maximal ideal.
Convergence in Backward Error of Relaxed GMRES
Authors: L. Giraud, S. Gratton, J. Langou
Venue: SIAM Journal on Scientific Computing (2007)

This work is the follow-up of the experimental study presented in [A. Bouras and V. Fraysse&acute;, SIAM J. Matrix Anal. Appl., 26 (2005), pp. 660-678]. It is based on and extends some theoretical results in [V. Simoncini and D. B. Szyld, SIAM J. Sci. Comput., 25 (2003), pp. 454-477; J. van den Eshof and G. L. G. Sleijpen, SIAM J. Matrix Anal. Appl., 26 (2004), pp. 125-153]. In a backward error framework we study the convergence of GMRES when the matrix-vector products are performed inaccurately. This inaccuracy is modeled by a perturbation of the original matrix. We prove the convergence of GMRES when the perturbation size is proportional to the inverse of the computed residual norm; this implies that the accuracy can be relaxed as the method proceeds which gives rise to the terminology &ldquo;relaxed GMRES.&rdquo; As for the exact GMRES we show under proper assumptions that only happy breakdowns can occur. Furthermore, the convergence can be detected using a byproduct of the algorithm. We explore the links between relaxed right-preconditioned GMRES and flexible GMRES (FGMRES). In particular, this enables us to derive a proof of convergence of FGMRES. Finally, we report results of numerical experiments to illustrate the behavior of the relaxed GMRES monitored by the proposed relaxation strategies.
Proceedings. 12th Annual IEEE Symposium on High Performance Interconnects
Venue: Proceedings of the High Performance Interconnects, 2004. on Proceedings. 12th Annual IEEE Symposium (2004)

The following topics are dealt with: high-performance interconnects; buffers; network innovation; parallel computers; network processor security; system level interconnects; PCI Express; distributed shared memory architecture; packet classification and lookup; routers and switches; high-speed optical interconnects; wireless enterprise backbone network architecture; global grid computing; high-bandwidth low-latency communication; Internet infrastructure security. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
On aggregate available bandwidth in many-to-one data transfer-modeling and applications
Authors: S. C. Hui, Jack Y. Lee
Venue: Multimedia Tools and Applications (2007)

This work investigates the modeling of aggregate available bandwidth in multi-sender network applications. Unlike the well-established client---server model, where there is only one server sending the requested data, the available bandwidth of multiple senders when combined together does exhibit consistent properties and thus can be modeled and estimated. Through extensive experiments conducted in the Internet this work proposed to model the aggregate available bandwidth using a normal distribution and then illustrates its application through a hybrid download-streaming algorithm and a playback-adaptive streaming algorithm for video delivery under different bandwidth availability scenarios. This new multi-source bandwidth model opens a new way to provide probabilistic performance guarantee in best-effort networks such as the Internet, and is particularly suitable for the emerging peer-to-peer applications, where having multiple sources is the norm rather than the exception.
A practical interprocedural dominance algorithm
Authors: Bjorn De Sutter, Ludo Van Put, Koen De Bosschere
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (2007)

Existing algorithms for computing dominators are formulated for control flow graphs of single procedures. With the rise of computing power, and the viability of whole-program analyses and optimizations, there is a growing need to extend the dominator computation algorithms to context-sensitive interprocedural dominators. Because the transitive reduction of the interprocedural dominator graph is not a tree, as in the intraprocedural case, it is not possible to extend existing algorithms directly. In this article, we propose a new algorithm for computing interprocedural dominators. Although the theoretical complexity of this new algorithm is as high as that of a straightforward iterative solution of the data flow equations, our experimental evaluation demonstrates that the algorithm is practically viable, even for programs consisting of several hundred thousands of basic blocks.
The spin-wave nanoscale reconfigurable mesh and the labeling problem
Authors: Mary M. Eshaghian-Wilner, Alex Khitun, Shiva Navab, Kang L. Wang
Venue: ACM Journal on Emerging Technologies in Computing Systems (JETC) (2007)

In this article, we present a nanoscale reconfigurable mesh which is interconnected by ferromagnetic spin-wave buses. In this architecture, unlike the traditional spin-based nano structures which transmit charge, waves are transmitted. As a result, the power consumption of the proposed modules can be low. This reconfigurable mesh, while requiring the same number of switches and buses as the standard reconfigurable mesh, is capable of simultaneously transmitting N waves on each of the spin-wave buses. Because of this highly parallel feature, very fast and fault-tolerant algorithms can be designed. To illustrate the superior performance of the proposed spin-wave reconfigurable mesh, we present three fast labeling algorithms.
Exploiting Narrow Values for Soft Error Tolerance
Authors: Oguz Ergin Osman Unsal, Xavier Vera, Antonio Gonzalez
Venue: IEEE Computer Architecture Letters (2006)

Soft errors are an important challenge in contemporary microprocessors. Particle hits on the components of a processor are expected to create an increasing number of transient errors with each new microprocessor generation. In this paper we propose simple mechanisms that effectively reduce the vulnerability to soft errors in a processor. Our designs are generally motivated by the fact that many of the produced and consumed values in the processors are narrow and their upper order bits are meaningless. Soft errors caused by any particle strike to these higher order bits can be avoided by simply identifying these narrow values. Alternatively, soft errors can be detected or corrected on the narrow values by replicating the vulnerable portion of the value inside the storage space provided for the upper order bits of these operands. We offer a variety of schemes that make use of narrow values and analyze their efficiency in reducing soft error vulnerability of level-0 data cache of the processor.
Genetically designed heuristics for the bin packing problem
Authors: Oana Muntean
Venue: Proceedings of the 2007 GECCO conference companion on Genetic and evolutionary computation (2007)

The bin packing problem (BPP) is a real-world problem that arises in different industrial applications related to minimization of space or time. The aim of this research is to automatically design an algorithm that places a collection of objects into the minimum number of fixed-size bins. For generating this heuristic we use Genetic Programming (GP) with a special set of terminals. The evolved strategy is compared to Best Fit Descending (BFD), a well-known heuristic for the bin packing problem. The results emphasize that evolved GP heuristics can perform equally and sometimes even better than BFD for the considered test problems.
Modular term-long CS2 projects
Authors: J. K. Huggins
Venue: Proceedings of the 30th Annual Frontiers in Education - Volume 02 (2000)

We present a model for a term-long computer science CS2 project which emphasizes modular code development and code-reuse while providing the opportunity to cover many traditional CS2 concepts. The project focuses on the construction of a simplified database system. The project is composed of a series of smaller assignments; each assignment requires students to replace or enhance work completed in previous assignments, thereby allowing students to experience the benefits of good modular design. Each project is of manageable size and complexity for both student and instructor, the final product is a program of non-trivial size and substantial functionality. The project can be easily varied from term to term in order to combat plagiarism, yet remains similar enough to administer reliably. We have successfully used this model over the last three years.
Using FPGA Devices to Accelerate Biomolecular Simulations
Authors: Sadaf R. Alam, Pratul K. Agarwal, Melissa C. Smith, Jeffrey S. Vetter, David Caliga
Venue: Computer (2007)

A field-programmable gate array implementation of a molecular dynamics simulation method reduces the microprocessor time-to-solution by a factor of three while using only high-level languages. The application speedup on FPGA devices increases with the problem size. The authors use a performance model to analyze the potential of simulating large-scale biological systems faster than many cluster-based supercomputing platforms.
Using The Meta-Environment for Maintenance and Renovation
Authors: M. G. J. van den Brand, M. Bruntink, G. R. Economopoulos, H. A. de Jong, P. Klint, T. Kooiker, T. van der Storm, J. J. Vinju
Venue: Proceedings of the 11th European Conference on Software Maintenance and Reengineering (2007)

The Meta-Environment is a flexible framework for lan- guage development, source code analysis and source code transformation. We highlight new features and demonstrate how the system supports key functionalities for software evolution: fact extraction, software analysis, visualization, and software transformation.
Analysis of the parameters of "Magnetic Disk-Magnetic Head" pair for magnetic recording
Authors: V. S. Semenov
Venue: Automation and Remote Control (2007)

Consideration was given to calculations of the parameters of transition between two opposite-magnetization domains in a thin-film working layer of the hard magnetic disk with regard for the saw-toothed form of transition. The transition parameters were related to the properties of the magnetic disk working layer and the magnetic head characteristics. For various recording densities, the levels of the playback signal and the resolution coefficient were determined.
Statistical mining in data streams
Authors: Edward Y. Chang
Venue:  (2006)

Recent years have seen a steady rise of a new class of data management systems called Data Stream Management Systems (DSMS). These systems manage rapid, high-volume data-streams with transient relations instead of static data with persistent relations. Data streams are common to applications such as network traffic and transaction monitoring systems, click-stream processors, industrial process control, and sensor networks. A DSMS operates on these continuous and time-varying data streams to facilitate on-the-fly query answering, and to support data acquisition, monitoring and analysis. In this dissertation, we present statistical stream mining solutions for effective online processing of streaming data. We focus research issues related to adaptive stream resource conservation and online mining in a DSMS. We have developed statistical linear and non-linear filtering techniques based on the Kalman Filter to capture temporal correlations in the streaming data. Such correlations help in stream resource conservation. We also propose techniques that capture spatial correlations between the streaming sources that further helps improving resource conservation and facilitates answering group-queries in an efficient manner. In addition to resource management and query processing, a DSMS needs to address issues related to online stream mining. Once the data stream arrives at a central server, effective mining techniques are necessary for stream analysis, before the data can be discarded. Since a stream continuously evolves with time, stream mining techniques need to be adaptive and should operate under a given memory constraint. We propose adaptive clustering solutions that use the kernel trick to capture non-linear relations in the streaming data. We also present OCODDS, a change-detection approach that can track evolutionary changes in the stream in both linear and non-linear settings. Finally, we present our techniques for effective acquisition and processing of data streams common to video sensor networks.
On the Learnability of Two Representations of Equivalence Partitioning and Boundary Value Analysis
Authors: Tafline Murnane, Karl Reed, Richard Hall
Venue: Proceedings of the 2007 Australian Software Engineering Conference (2007)

Currently, Equivalence Partitioning and Boundary Value Analysis are taught at La Trobe University using Myers' original representation of these black-box testing methods. We previously proposed an alternative representation called Atomic Rules. In this paper we present the statistical results of two similar experiments that examine which of these approaches enable students to write more complete and correct black-box test sets and which approach students prefer to use. We compare the results of these experiments and discuss how the results could change the teaching of black-box testing methods at La Trobe University and in industry.
Debugging storage management problems in garbage-collected environments
Authors: David L. Detlefs, Bill Kalsow
Venue: Proceedings of the USENIX Conference on Object-Oriented Technologies on USENIX Conference on Object-Oriented Technologies (COOTS) (1995)

Garbage collection does not solve all storage management problems; programs allocate too much garbage, requiring excess collection, and may retain too much storage, causing heaps to grow too large. This paper discusses these problems and presents tools implemented in the SRC Modula-3 system that help solve them.
Weighted Information Retrieval Algorithms for Onsite Object Service
Authors: Ping Cai, Liang He
Venue: Proceedings of the International Multi-Conference on Computing in the Global Information Technology (2007)

Designing proper algorithm is necessary for applications that query and analyze mass-information for high efficiency in various information services. In this paper, we discuss weighted information retrieval algorithms for an newly service, Onsite Object Service. Four retrieval algorithms with one-dimension weight and one retrieval algorithm with multi-dimension weight are proposed to address the requirements of OOS. Detailed performance analysis and comparison about the advantage and disadvantage of these 5 different algorithms are presented later. And at last a conclusion is drawn about the recommendation for these algorithms in different scenarios.