ppxscal/embedding_network huggingface dataset:
An Event Stream Driven Approximation for the Analysis of Real-Time Systems
Authors: Karsten Albers, Frank Slomka
Venue: Proceedings of the 16th Euromicro Conference on Real-Time Systems (2004)

This paper presents a new approach to understand theevent stream model. Additionally a new approximationalgorithm for the feasibility test of the sporadic and thegeneralized multiframe task system scheduled by earliestdeadline first is presented. The new algorithm has polynomialcomplexity to solve the problem of schedulabilityanalysis. The approximation error of the algorithm isbounded. In contrary to earlier work, where the errordepends on the different deadlines of the tasks, the errorof our algorithm depends only on the capacity of the chosenprocessor. It guarantees the acceptances on a processorwith slightly higher capacity than the unknownoptimal processor. While the algorithm is scalable andthe run-time depends on the chosen error, a trade-offbetween running time and error is possible.
CAMA: A Multi-Valued Satisfiability Solver
Authors: Cong Liu, Andreas Kuehlmann, Matthew W. Moskewicz
Venue: Proceedings of the 2003 IEEE/ACM international conference on Computer-aided design (2003)

This paper presents the multi-valued SAT solver CAMA. CAMAgeneralizes the recently developed speed-up techniques usedin state-of-the-art binary SAT solvers, such as the two-literal-watching scheme for Boolean constraint propagation (BCP), conflict-based learning with identifying the first unique implication point (UIP), and non-chronological back-tracking. In addition, a novel minimum value set (MVS) technique is introduced for improving the efficiency of conflict-based learning. By analyzing the conflict clauses, MVS can potentially prune conflictingspace that has not been searched before. Two different decisionheuristics are discussed and evaluated. Finally the performanceof CAMA is compared with Chaff using on a one-hot-encodingscheme. The experimental results show that, for MV-SAT problemswith large variable domains, CAMA outperforms Chaff.
Requirements/design debugging: session summary
Authors: Peter Bates
Venue: ACM SIGSOFT Software Engineering Notes (1983)

This session was essentially a continuation of the earlier session on Knowledge-Based systems. The discussion proceeded along two dimensions. One is the paradigm used to, in some sense, debug high-level specifications. This is further broken into the 'current' and the 'operational specifications' paradigms. The other dimension is one of techniques for implementing these views. This dimension also has only two aspects, current techniques and knowledge-based techniques. The plan for the session was to introduce the technologies that may or may not exist to support these capabilities followed by a debate on these methods. There are four areas to be discussed in terms of technology---symbolic evaluation, fault analysis, behavior expectations and natural language explanations.
Efficient method of adaptive sign detection for 4&#x00d7;4 determinants using a standard arithmetic processing unit
Authors: Toshiya Yamauchi, Norimasa Yoshida, Jun Doi, Fujio Yamaguchi
Venue: The Visual Computer: International Journal of Computer Graphics (2004)

We propose an efficient and exact method for the adaptive sign detection of 4&#x00d7;4 determinants using a standard arithmetic unit. The entities of determinants are variable length integers (integers of arbitrary bit length). The integers are expressed in 16-bit data units, and the sign detection is reduced to the computation of 4&#x00d7;4 determinants of 16-bit integers. To accelerate the computation, the calculation is performed by using a standard arithmetic unit. We have implemented our method and confirmed that it significantly improves the computation time of 4&#x00d7;4 determinants. The method can be applicable to many geometric algorithms that need the exact sign evaluation of 4&#x00d7;4 determinants, especially to construct robust geometric algorithms.
Adjustable Width Linear Combinational Scan Vector Decompression
Authors: C. V. Krishna, Nur A. Touba
Venue: Proceedings of the 2003 IEEE/ACM international conference on Computer-aided design (2003)

A new scheme for combinational linear expansion isproposed for decompression of scan vectors. It has thecapability to adjust the width of the linear expansion each clockcycle. This eliminates the requirement that every scan bit-slicebe in the output space of the linear decompressor. Depending onhow specified the current bit-slice is, the decompressor may loadall scan chains or may load only a subset of the scan chains.This provides the nice feature that any scan vector can begenerated using the proposed scheme regardless of the numberor distribution of the specified bits. Thus, the proposed schemeallows the use of any ATPG procedure without any constraints.Moreover, it allows greater compression to be achieved thanfixed width expansion techniques since the ratio of the number ofscan chains to the number of tester channels can be scaled muchlarger. A procedure for designing and optimizing the adjustablewidth decompression hardware and obtaining the compresseddata is described. Experimental data indicates that the proposedscheme is simple yet very effective.
Simple model of a multi-batch driven pipeline
Authors: Sašo Blažič, Drago Matko, Gerhard Geiger
Venue: Mathematics and Computers in Simulation (2004)

The problem of modelling and simulating pipelines that are used for transporting different fluids is addressed in the paper. The problem is solved by including fluid density in the model beside pressure and velocity of the medium. First, the system of nonlinear partial differential equations is derived. Then, the obtained model is linearised and transformed into the transfer function form with three inputs and three outputs. Four different forms of model description are presented in the paper. Since transfer functions are transcendent, they cannot be simulated using classical tools. Rational transfer function approximation of the model was found and that simple model was validated on the real industrial pipeline. It was also compared to the model that does not take the changes in fluid density into account. The latter model cannot cope with batch changes whereas the proposed one can.
Non-liouvillian solutions for second order Linear ODEs
Authors: L. Chan, E. S. Cheb-Terrab
Venue: Proceedings of the 2004 international symposium on Symbolic and algebraic computation (2004)

There exist sound literature and algorithms for computing Liouvillian solutions for the important problem of linear ODEs with rational coefficients. Taking as sample the 363 second order equations of that type found in Kamke's book, for instance, 51% of them admit Liouvillian solutions and so are solvable using Kovacic's algorithm. On the other hand, special function solutions not admitting Liouvillian form appear frequently in mathematical physics, but there are not so general algorithms for computing them. In this paper we present an algorithm for computing special function solutions which can be expressed using the ;2;F;1;, ;1;F;1; or ;0;F;1; hypergeometric functions. The algorithm is easy to implement in the framework of a computer algebra system and systematically solves 91% of the 363 Kamke's linear ODE examples mentioned.
An Example of the ESTEST Approach to Combining Unstructured Text and Structured Data
Authors: Dean Williams, Alexandra Poulovassilis
Venue: Proceedings of the Database and Expert Systems Applications, 15th International Workshop (2004)

In this paper, we demonstrate the use of the ESTEST system, which combines the data integration approach with techniques from Information Extraction in order to allow information from ontologies and natural language sources to be integrated with other, semantically related, structured or semi-structured data.
Unification in Privacy Policy Evaluation - Translating EPAL into Prolog
Venue: Proceedings of the Fifth IEEE International Workshop on Policies for Distributed Systems and Networks (2004)

Privacy policy evaluation engines enable querieswhether a specific user is allowed to access specific datafor a specific purpose. While tools for authoring, maintaining,and auditing privacy policies already exist, no tool existsyet to deal with unification within such policies, e.g., toenable queries if data might be modified by some user, orhow many user entries satisfy a certain constraint. We showhow this can can be achieved by embedding enterprise privacypolicies into Prolog. We show this concretely for IBM'sEnterprise Privacy Authorization Language (EPAL). Basedon the unification mechanisms of Prolog, our work enablesgeneral queries for privacy policies as well as quantitativemeasurements.
Coupon Based Incentive Systems and the Implications of Equilibrium Theory
Authors: Anargyros Garyfalos, Kevin C. Almeroth
Venue: Proceedings of the IEEE International Conference on E-Commerce Technology (2004)

"Coupons" is an incentive scheme that gives users credit for forwarding information to other users over wireless, potentially ad hoc networks. Having previously performed an initial evaluation of the main characteristics, this paper first examines how this idea works in more complex, hybrid networks and then focuses on the effects of user behavior on system performance. By considering implications of game theory concepts, such as Evolutionary Stable Strategies, particular emphasis is given on how we can reasonably constrain behavior to a range of values, all of which result in good system performance. Results show that by developing and validating effective incentive systems, we can greatly improve the ability to efficiently disseminate information to users throughout the evolving Internet.
Medium access control with coordinated adaptive sleeping for wireless sensor networks
Authors: Wei Ye, John Heidemann, Deborah Estrin
Venue: IEEE/ACM Transactions on Networking (TON) (2004)

This paper proposes S-MAC, a medium access control (MAC) protocol designed for wireless sensor networks. Wireless sensor networks use battery-operated computing and sensing devices. A network of these devices will collaborate for a common application such as environmental monitoring. We expect sensor networks to be deployed in an ad hoc fashion, with nodes remaining largely inactive for long time, but becoming suddenly active when something is detected. These characteristics of sensor networks and applications motivate a MAC that is different from traditional wireless MACs such as IEEE 802.11 in several ways: energy conservation and self-configuration are primary goals, while per-node fairness and latency are less important. S-MAC uses a few novel techniques to reduce energy consumption and support self-configuration. It enables low-duty-cycle operation in a multihop network. Nodes form virtual clusters based on common sleep schedules to reduce control overhead and enable traffic-adaptive wake-up. S-MAC uses in-channel signaling to avoid overhearing unnecessary traffic. Finally, S-MAC applies message passing to reduce contention latency for applications that require in-network data processing. The paper presents measurement results of S-MAC performance on a sample sensor node, the UC Berkeley Mote, and reveals fundamental tradeoffs on energy, latency and throughput. Results show that S-MAC obtains significant energy savings compared with an 802.11-like MAC without sleeping.
Improved generalized neuron model for short-term load forecasting
Authors: D. K. Chaturvedi, M. Mohan, R. K. Singh, P. K. Kalra
Venue: Soft Computing - A Fusion of Foundations, Methodologies and Applications (2004)

The conventional neural networks consisting of simple neuron models have various drawbacks like large training time for complex problems, huge data requirement to train a non linear complex problems, unknown ANN structure, the relatively larger number of hidden nodes required, problem of local minima etc. To make the Artificial Neural Network more efficient and to overcome the above-mentioned problems the new improved generalized neuron model is proposed in this work. The proposed neuron models have both summation (&#x03a3;) and product (&#x03c0;) as aggregation function. The generalized neuron models have flexibility at both the aggregation and activation function level to cope with the non-linearity involved in the type of applications dealt with. The training and testing performance of these models have been compared for Short Term Load Forecasting Problem.
Computing and stability in cortical networks
Authors: Peter E. Latham Sheila Nirenberg
Venue: Neural Computation (2004)

Cortical neurons are predominantly excitatory and highly interconnected. In spite of this, the cortex is remarkably stable: normal brains do not exhibit the kind of runaway excitation one might expect of such a system. How does the cortex maintain stability in the face of this massive excitatory feedback? More importantly, how does it do so during computations, which necessarily involve elevated firing rates? Here we address these questions in the context of attractor networks--networks that exhibit multiple stable states, or memories. We find that such networks can be stabilized at the relatively low firing rates observed in vivo if two conditions are met: (1) the background state, where all neurons are firing at low rates, is inhibition dominated, and (2) the fraction of neurons involved in a memory is above some threshold, so that there is sufficient coupling between the memory neurons and the background. This allows "dynamical stabilization" of the attractors, meaning feedback from the pool of background neurons stabilizes what would otherwise be an unstable state. We suggest that dynamical stabilization may be a strategy used for a broad range of computations, not just those involving attractors.
Interactive blood simulation for virtual surgery based on smoothed particle hydrodynamics
Authors: Matthias Müller, Simon Schirm, Matthias Teschner
Venue: Technology and Health Care (2004)

In this paper, we propose an interactive method based on Smoothed Particle Hydrodynamics (SPH) to simulate blood as a fluid with free surfaces. While SPH was originally designed to simulate astronomical objects, we gear the method towards fluid simulation by deriving the force density fields directly from the Navier-Stokes equation and by adding a term to model surface tension effects. In contrast to Eulerian grid-based approaches, the particle-based approach makes mass conservation equations and convection terms dispensable which reduces the complexity of the simulation. In addition, the particles can directly be used to render the surface of the fluid. Our method can be used in interactive surgical training systems with models of up to 3000 particles.
Compressing historical information in sensor networks
Authors: Antonios Deligiannakis, Yannis Kotidis, Nick Roussopoulos
Venue: Proceedings of the 2004 ACM SIGMOD international conference on Management of data (2004)

We are inevitably moving into a realm where small and inexpensive wireless devices would be seamlessly embedded in the physical world and form a wireless sensor network in order to perform complex monitoring and computational tasks. Such networks pose new challenges in data processing and dissemination because of the limited resources (processing, bandwidth, energy) that such devices possess. In this paper we propose a new technique for compressing multiple streams containing historical data from each sensor. Our method exploits correlation and redundancy among multiple measurements on the same sensor and achieves high degree of data reduction while managing to capture even the smallest details of the recorded measurements. The key to our technique is the base signal, a series of values extracted from the real measurements, used for encoding piece-wise linear correlations among the collected data values. We provide efficient algorithms for extracting the base signal features from the data and for encoding the measurements using these features. Our experiments demonstrate that our method by far outperforms standard approximation techniques like Wavelets. Histograms and the Discrete Cosine Transform, on a variety of error metrics and for real datasets from different domains.
Introducing undecidability
Authors: Judith Gal-Ezer, Dvir Lanzberg, Daphna Shahak
Venue: Proceedings of the 9th annual SIGCSE conference on Innovation and technology in computer science education (2004)

In this paper we suggest introducing undecidability to students in relatively early stages of their studies, in a way we used succefully in recent semesters.
PB-LRU: a self-tuning power aware storage cache replacement algorithm for conserving disk energy
Authors: Qingbo Zhu, Asim Shankar, Yuanyuan Zhou
Venue: Proceedings of the 18th annual international conference on Supercomputing (2004)

Energy consumption is an important concern at data centers, where storage systems consume a significant fraction of the total energy. A recent study proposed power-aware storage cache management to provide more opportunities for the underlying disk power management scheme to save energy. However, the on-line algorithm proposed in that study requires cumbersome parameter tuning for each workload and is therefore difficult to apply to real systems.This paper presents a new power-aware on-line algorithm called PB-LRU (Partition-Based LRU) that requires little parameter tuning. Our results with both real system and synthetic workloads show that PB-LRU without any parameter tuning provides similar or even better performance and energy savings than the previous power-aware algorithm with the best parameter setting for each workload.
Molecular Visualizations of DNA
Venue: ACM SIGGRAPH 2003 video review on Electronic theater program on Electronic theater program - Volume 144 (2003)

These DNA molecular visualizations were created for the multifaceted 'DNA' project, celebrating the 50th anniversary in 2003 of the discovry of the double helix. The 'DNA' project includes a five-part documentary series, museum film and online resources for teachers and students. The dynamics and molecular shapes were based on X-ray crystallographic models and other published scientific data sets. Leading scientists, including many Nobel Laureates, critiqued the animations during their development. Particular effort was made to ensure that relative shapes, sizes and 'real-time' dynamics were as accurate as possible. The primary system used for bulding the animations was Maya PaintFX. Copyright held by creator.
XSeq: an indexing infrastructure for tree pattern queries
Authors: Xiaofeng Meng, Yu Jiang, Yan Chen, Haixun Wang
Venue: Proceedings of the 2004 ACM SIGMOD international conference on Management of data (2004)

Given a tree-pattern query, most XML indexing approaches decompose it into multiple sub-queries, and then join their results to provide the answer to the original query. Join operations have been identified as the most time-consuming component in XML query processing. XSeq is a powerful XML indexing infrastructure which makes tree patterns a first class citizen in XML query processing. Unlike most indexing methods that directly manipulate tree structures, XSeq builds its indexing infrastructure on a much simpler data model: sequences. That is, we represent both XML data and XML queries by structure-encoded sequences. We have shown that this new data representation preserves query equivalence, and more importantly, through subsequence matching, structured queries can be answered directly without resorting to expensive join operations. Moreover, the XSeq infrastructure unifies indices on both the content and the structure of XML documents, hence it achieves an additional performance advantage over methods indexing either just content or structure, or indexing them separately.
Note on the relationship between probabilistic and fuzzy clustering
Authors: W. Shitong, K. F. Chung, S. Hongbin, Z. Ruiqiang
Venue: Soft Computing - A Fusion of Foundations, Methodologies and Applications (2004)

In this short communication, based on Renyi entropy measure, a new Renyi information based clustering algorithm A is presented. Algorithm A and the well-known fuzzy clustering algorithm FCM have the same clustering track. This fact builds the very bridge between probabilistic clustering and fuzzy clustering, and fruitful research results on Renyi entropy measure may help us to further understand the essence of fuzzy clustering.
Phased Array and Adaptive Antenna Transceivers in Wireless Sensor Networks
Authors: Ruimin Huang, Yiannos Manoli
Venue: Proceedings of the Digital System Design, EUROMICRO Systems (2004)

Adaptive antenna and phased array are powerful techniques in wireless communication. The phased array can transmit the signal to the preferred direction with the desired coverage. It introduces the concept of space division multiple access in addition to the CDMA, TDMA and FDMA. Additionally adaptive antenna can use the same arrangement of the antenna array to improve the SINR dramatically by spatially filtering out any interference. These two techniques are promising for introducing flexible and efficient algorithms for wireless sensor networks. This paper focuses on the structure implemented in the sensor node transceiver and uses the 4-element circular antenna array as an example. It also discusses what advantages these techniques provide in wireless sensor networks.
Thresholds: On the Need for Frame Discarding in Cell-Switched Networks
Authors: Nelson L. S. Da Fonseca, Sergio A. Yunes
Venue: Journal of Network and Systems Management (2004)

This paper introduces a novel policing mechanism, called Packet Leaky Bucket in which all cells of a frame are marked with the same level of priority. Moreover, it discusses the need for having a frame discard mechanism in cell-switched networks when frame-oriented policing mechanisms are used.
Stability in legged locomotion
Authors: Toma&#x017e; Kar&#x010d;nik
Venue: Biological Cybernetics (2004)

Stability is a key element in a gait synthesis. Static stability margins are widely adopted in crawlers, while no similar approach has been developed for dynamically stable systems. Utilizing an analytical approach, we developed a set of easy-to-calculate stability indices to describe instantaneous static and dynamic (In)stability for a certain group of walking systems. The analysis is based on a thorough analysis of the interaction between ground reaction forces and the walking system. The indices are applicable to walking systems regardless of the number of legs or mechanical/biological design. We show that static and dynamic stability are independent of each other. We suggest a possible categorization of gait modes based on stability. Stability characteristics are analyzed in a healthy and highly pathological human gait. Finally, we discuss the applicability of the proposed methods.
An Introduction to the Web Services Policy Language (WSPL)
Venue: Proceedings of the Fifth IEEE International Workshop on Policies for Distributed Systems and Networks (2004)

The Web Services Policy Language (WSPL) issuitable for specifying a wide range of policies,including authorization, quality-of-service, quality-of-protection,reliable messaging, privacy, andapplication-specific service options. WSPL is ofparticular interest in several respects. It supportsmerging two policies, resulting in a single policy thatsatisfies the requirements of both, assuming such apolicy exists. Policies can be based on comparisonsother than equality, allowing policies to depend onfine-grained attributes such as time of day, cost, ornetwork subnet address. By using standard data typesand functions for expressing policy parameters, astandard policy engine can support any policy. Thesyntax is a strict subset of the OASIS eXtensible AccessControl Markup Language (XACML) Standard. WSPLhas been implemented, and is under consideration as astandard policy language for use with web services.