ppxscal/embedding_network huggingface dataset:
The Best Bits in an Iris Code
Authors: Karen P. Hollingsworth, Kevin W. Bowyer, Patrick J. Flynn
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2009)

Iris biometric systems apply filters to iris images to extract information about iris texture. Daugman's approach maps the filter output to a binary iris code. The fractional Hamming distance between two iris codes is computed and decisions about the identity of a person are based on the computed distance. The fractional Hamming distance weights all bits in an iris code equally. However, not all the bits in an iris code are equally useful. Our research is the first to present experiments documenting that some bits are more consistent than others. Different regions of the iris are compared to evaluate their relative consistency, and contrary to some previous research, we find that the middle bands of the iris are more consistent than the inner bands. The inconsistent-bit phenomenon is evident across genders and different filter types. Possible causes of inconsistencies, such as segmentation, alignment issues, and different filters are investigated. The inconsistencies are largely due to the coarse quantization of the phase response. Masking iris code bits corresponding to complex filter responses near the axes of the complex plane improves the separation between the match and nonmatch Hamming distance distributions.
An empirical model for probability of packet reception in vehicular ad hoc networks
Authors: Moritz Killat, Hannes Hartenstein
Venue: EURASIP Journal on Wireless Communications and Networking (2009)

Today's advanced simulators facilitate thorough studies on VANETs but are hampered by the computational effort required to consider all of the important influencing factors. In particular, large-scale simulations involving thousands of communicating vehicles cannot be served in reasonable simulation times with typical network simulation frameworks. A solution to this challenge might be found in hybrid simulations that encapsulate parts of a discrete-event simulation in an analytical model while maintaining the simulation's credibility. In this paper, we introduce a hybrid simulation model that analytically represents the probability of packet reception in an IEEE 802.11p network based on four inputs: the distance between sender and receiver, transmission power, transmission rate, and vehicular traffic density. We also describe the process of building our model which utilizes a large set of simulation traces and is based on general linear least squares approximation techniques. The model is then validated via the comparison of simulation results with the model output. In addition, we present a transmission power control problem in order to show the model's suitability for solving parameter optimization problems, which are of fundamental importance to VANETs.
Domain-Driven Data Mining: Methodologies and Applications
Authors: Chengqi Zhang, Longbing Cao
Venue: Proceeding of the 2006 conference on Advances in Intelligent IT: Active Media Technology 2006 (2006)

The aims and objectives of data mining is to discover actionable knowledge of main interest to real user needs, which is one of Grand Challenges in KDD. Most extant data mining is a data-driven trial-an-error process. Patterns discovered via predefined models in the above process are often of limited interest to constraint-based real business. In order to work out patterns really interesting and actionable to the real world, pattern discovery is more likely to be a domain-driven human-machine-cooperated process. This talk proposes a practical data mining methodology named “domain-driven data mining”. The main ideas include a Domain-Driven In-Depth Pattern Discovery framework (DDID-PD), constraint-based mining, in-depth mining, human-cooperated mining and loop-closed mining. Guided by this methodology, we demonstrate some of our work in identifying useful correlations in real stock markets, for instance, discovering optimal trading rules from the existing rule classes, and mining trading rule-stock correlations in stock exchange data. The results have attracted strong interest from both traders and researchers in stock markets. It has shown that the methodology is potential for guiding deep mining of patterns interesting to real business.
Qualitative behavior rules for the cold rolling process extracted from trained ANN via the FCANN method
Authors: Luis E. Zárate, Sérgio M. Dias
Venue: Engineering Applications of Artificial Intelligence (2009)

Nowadays, artificial neural networks (ANN) are being widely used in the representation of different systems and physics processes. In this paper, a neural representation of the cold rolling process will be considered. In general, once trained, the networks are capable of dealing with operational conditions not seen during the training process, keeping acceptable errors in their responses. However, humans cannot assimilate the knowledge kept by those networks, since such knowledge is implicit and difficult to be extracted. For this reason, the neural networks are considered a ''black-box''. In this work, the FCANN method based on formal concept analysis (FCA) is being used in order to extract and represent knowledge from previously trained ANN. The new FCANN approach permits to obtain a non-redundant canonical base with minimum implications, which qualitatively describes the process. The approach can be used to understand the relationship among the process parameters through implication rules in different operational conditions on the load-curve of the cold rolling process. Metrics for evaluation of the rules extraction process are also proposed, which permit a better analysis of the results obtained.
Enterprise Cluster Knowledge Disseminate in Small-World Network
Authors: Jian Tan, Xianjia Wang
Venue: Proceedings of the 6th International Symposium on Neural Networks: Advances in Neural Networks - Part II (2009)

We use small world network model to describe dissemination behavior of knowledge in enterprise cluster. Deeming the enterprise cluster as a closed system which means the total number of the enterprise cluster member unchanged, we discussed knowledge dissemination regularity in enterprise cluster by building a mathematic model based on small-world network theory, analyzed the key control parameter which influence knowledge dissemination, gave an estimate method of the parameter.
Generalized formal models for faceted user interfaces
Authors: Edward C. Clarkson, Shamkant B. Navathe, James D. Foley
Venue: Proceedings of the 9th ACM/IEEE-CS joint conference on Digital libraries (2009)

Faceted metadata and navigation have become major topics in library science, information retrieval and Human-Computer Interaction (HCI). This work surveys a range of extant approaches in this design space, classifying systems along several relevant dimensions. We use that survey to analyze the organization of data and its querying within faceted browsing systems. We contribute formal entity-relationship (ER) and relational data models that explain that organization and relational query models that explain systems' browsing functionality. We use these types of models since they are widely used to conceptualize data and to model back-end data stores. Their structured nature also suggests ways in which both the models and faceted systems might be extended.
Towards Efficient Belief Update for Planning-Based Web Service Composition
Authors: Jörg Hoffmann
Venue: Proceeding of the 2008 conference on ECAI 2008: 18th European Conference on Artificial Intelligence (2008)

At the “functional level”, Semantic Web Services (SWS) are described akin to planning operators, with preconditions and effects relative to an ontology; the ontology provides the formal vocabulary and an axiomatisation of the underlying domain. Composing such SWS is similar to planning. A key obstacle in doing so effectively is handling the ontology axioms, which act as state constraints. Computing the outcome of an action involves the frame and ramification problems, and corresponds to belief update. The complexity of such updates motivates the search for tractable classes. Herein we investigate a class that is of practical relevance because it deals with many commonly used ontology axioms, in particular with attribute cardinality upper bounds which are not handled by other known tractable classes. We present an update computation that is exponential only in a comparatively uncritical parameter; we present an approximate update which is polynomial in that parameter as well.
A Novel Fault Localization Technique Based on Deconvolution and Calibration of Power Pad Transients Signals
Authors: Reza M. Rad, Jim Plusquellic
Venue: Journal of Electronic Testing: Theory and Applications (2009)

This paper describes a new fault localization method that is based on the analysis of power supply transient signals. Impulse response functions derived from the power grid are used to de-construct the measured power port transient signals into a set of gate level transients generated by the logic gates as signals propagate along paths in the circuit. By comparing these gate transients with those obtained from a defect-free chip or simulation model, it is possible to identify anomalies produced by defects and to locate them to specific path segments in the layout. Impulse response functions are used to significantly reduce both the attenuation effects of the power grid on the gate-generated transients and the chip-to-chip impedance variations in the power grid and test environment. Non-linear calibration techniques are proposed to reduce the chip-to-chip variations in path delays introduced by process variations. The procedure is demonstrated using simulation experiments to locate the position of defects to one or a small group of gates.
Performance Comparisons of Basic OpenMP Constructs
Authors: Achal Prabhakar, Vladimir Getov, Barbara Chapman
Venue: Proceedings of the 4th International Symposium on High Performance Computing (2009)

OpenMP has become the de-facto standard for shared memory parallel programming. The directive based nature of OpenMP allows incremental and portable developement of parallel application for a wide range of platforms. The fact that OpenMP is easy to use implies that a lot of details are hidden from the end user. Therefore, basic factors like the runtime system, compiler optimizations and other implementation specific issues can have a significant impact on the performance of an OpenMP application. Frequently, OpenMP constructs can have widely varying performance on different operating platforms and even with different compilers on the same machine. This makes it very important to have a comparative study of the low-level performance of individual OpenMP constructs. In this paper, we present an enhanced set of microbenchmarks for OpenMP derived from the EPCC benchmarks and based on the SKaMPI benchmarking framework. We describe the methodology of evaluation followed by details of some of the constructs and their performance measurement. Results from experiments conducted on the IBM SP3 and the SUN SunFire systems are presented for each construct.
On a generalization of Jentzsch's theorem
Authors: Hans-Peter Blatt, Simon Blatt, Wolfgang Luh
Venue: Journal of Approximation Theory (2009)

Let E be a compact subset of C with connected, regular complement @W=C@?@?E and let G(z) denote Green's function of @W with pole at ~. For a sequence (p"n)"n"@?"@L of polynomials with degp"n=n, we investigate the value-distribution of p"n in a neighbourhood U of a boundary point z"0 of E if G(z) is an exact harmonic majorant of the subharmonic functions 1nlog|p"n(z)|,n@?@L in C@?@?E. The result holds for partial sums of power series, best polynomial approximations, maximally convergent polynomials and can be extended to rational functions with a bounded number of poles.
The effect of social influence and curfews on civil violence
Authors: Michael Garlick, Maria Chli
Venue: Proceedings of The 8th International Conference on Autonomous Agents and Multiagent Systems - Volume 2 (2009)

We investigate the policies of (1) restricting social influence and (2) imposing curfews upon interacting citizens in a community. We compare their effects on the social order and the emerging levels of civil violence. We develop an agent-based model that is used to simulate a community of citizens and the police force that guards it. We find that restricting social influence pacifies rebellious societies, but has the opposite effect on peaceful ones. Curfews exhibit a pacifying effect across all types of society.
The Cache Complexity of Multithreaded&#x00a0;Cache&#x00a0;Oblivious Algorithms
Authors: Matteo Frigo, Volker Strumpen
Venue: Theory of Computing Systems (2009)

We present a technique for analyzing the number of cache misses incurred by multithreaded cache oblivious algorithms on an idealized parallel machine in which each processor has a private cache. We specialize this technique to computations executed by the Cilk work-stealing scheduler on a machine with dag-consistent shared memory. We show that a multithreaded cache oblivious matrix multiplication incurs cache misses when executed by the Cilk scheduler on a machine with P processors, each with a cache of size Z, with high probability. This bound is tighter than previously published bounds. We also present a new multithreaded cache oblivious algorithm for 1D stencil computations incurring cache misses with high probability, one for Gaussian elimination and back substitution, and one for the length computation part of the longest common subsequence problem incurring cache misses with high probability.
Simulation study of the functioning of LFSR for grade 4 irreducible polynomials
Authors: Mirella Amelia Mioc
Venue: Proceedings of the 8th WSEAS International Conference on Software engineering, parallel and distributed systems (2009)

It all began in Colossus, with a code-breaking machine that was one of the first known examples of a shift register. During the ages, the shift registers demonstrated their capacity to be the heart of any digital system. Now the applications are well-known as well in cryptography (Rijndael Algorithm) as in error correcting and in wireless communication systems. This paper contains an analysis of functioning for Linear Feedback Shift Register and Multiple Input-output Shift Register using grade 4 irreducible polynomials. Three kinds of scheme for implementation of a LFSR were analyzed and a formula that linked the results was verified.
Parallelizing secure linear programming
Authors: Rafael Deitos, Florian Kerschbaum
Venue: Concurrency and Computation: Practice Experience (2009)

Information sharing in supply chain management can dramatically improve the performance of the supply chain. Although many such problems can be modeled and efficiently solved using linear programming (LP), security requirements prevent their implementation in the traditional way. Companies are simply reluctant to exchange such sensitive information. Secure multi-party computation can help by realizing protocols with guaranteed security. However, efficiency is a major concern. Parallel computing presents an opportunity to improve performance utilizing inherent parallel secure operations. This work focuses on practical approaches to privacy preserving parallel protocols for collaborative LP. First, it theoretically compares the approach of parallelizing a secure algorithm and securing a parallel algorithm. Their complexity being equal we implemented the simpler choice: parallelizing a secure algorithm. Different synchronization methods for the implementation are compared under different network conditions. Given the best implementation, the performance is almost independent of the network conditions, but parallelization, i.e. number of threads, needs to be adapted to such conditions. We present and evaluate an adaptive scheduling algorithm for the dynamic selection of the number of threads, such that it's not necessary to statically and up-front determine the number for optimal speed-up. The algorithm can even deal with varying network conditions. Copyright &copy; 2009 John Wiley & Sons, Ltd.
Evaluation of Different BDD Libraries to Extract Concepts in FCA --- Perspectives and Limitations
Authors: Andrei Rimsa, Luis E. Zárate, Mark A. Song
Venue: Proceedings of the 9th International Conference on Computational Science: Part I (2009)

This paper presents evaluation of different types of Binary Decision Diagrams (BDDs) applied to Formal Concept Analysis (FCA). The aim is to increase the FCA capability to handle large formal contexts and perform faster operations over different types of this data structure. The main idea is to represent formal context using BDDs for later extraction of the set of all formal concepts from this implicit representation. A comparison of a concept extraction algorithm using contexts implemented as table and BDD are presented. BDD is evaluated over two different implementation libraries, BuDDy and CUDD. A ZBDDs (Zero-Supressed BDDs) version of the concepts extraction algorithm is also provided. BDD has been evaluated based on several types of randomly generated synthetic contexts with large amounts of objects. Contexts are evaluated according to the computational time complexity required to build and extract the set of all concepts from it. In this work, it is shown that BDD could be used to deal with large formal contexts especially when those have few attributes and many objects. To overcome the limitations of having contexts with fewer attributes, one could consider vertical partitions of the context to be used with distributed FCA algorithms based on BDD.
Properties of fuzzy systems
Authors: Constantin Volosencu
Venue: WSEAS TRANSACTIONS on SYSTEMS (2009)

The paper presents a short review of some main properties of the most general fuzzy systems used in a large class of practical applications. The fuzzy systems, implemented using different rule bases, fuzzy values, membership functions, fuzzyfication and defuzzification methods, may be classified based on these fuzzy methods used in their development. This paper proposes a unitary theory for describing Mamdani fuzzy controllers based on their characteristics. Fuzzy rules bases may be seen as fuzzy applications between fuzzy sets. These rule bases have algebraic properties as: commutative law, neutral element and symmetric elements. The fuzzy systems may be analytical described with MISO, SISO and gain transfer characteristics, which may be calculated using computer programs. The fuzzy systems have algebraic properties as: commutative law and symmetric elements. These algebraic properties may be noticed on their transfer characteristics. The fuzzy systems have a variable gain with their inputs. Some gain characteristics values are presented. The rule bases and the fuzzy systems have the sector property. The paper emphasizes, based on the transfer characteristics, planar and spatial sector properties useful in stability analysis with Lyapunov techniques. The transfer characteristics, system linear characteristic around the origin and the gain in origin are usefull in the design of fuzzy PID controllers. Based on transient characteristics of fuzzy control systems some quality criteria are presented. The fuzzy systems used in control assure better control quality criteria and a greater robustness at disturbances effects and at the error at the identification of controlled processes parameters.
ACM Europe
Authors: Wendy Hall
Venue: Communications of the ACM (2009)

Increasing ACM's relevance and influence as a membership organization in the global computing community has been a top priority from the outset of my presidency.
Sourcerer: An internet-scale software repository
Authors: Sushil Bajracharya, Joel Ossher, Cristina Lopes
Venue: Proceedings of the 2009 ICSE Workshop on Search-Driven Development-Users, Infrastructure, Tools and Evaluation (2009)

Vast quantities of open source code are now available online, presenting a great potential resource for software developers. Yet the current generation of open source code search engines fail to take advantage of the rich structural information contained in the code they index. We have developed Sourcerer, an infrastructure for large-scale indexing and analysis of open source code. By taking full advantage of this structural information, Sourcerer provides a foundation upon which state of the art search engines and related tools easily be built. We describe the Sourcerer infrastructure, present the applications that we have built on top of it, and discuss how existing tools could benefit from using Sourcerer.
Decomposition of ordinary difference polynomials
Authors: Mingbo Zhang, Xiao-Shan Gao
Venue: Journal of Symbolic Computation (2009)

In this paper, we present an algorithm to decompose ordinary non-linear difference polynomials with rational functions as coefficients. The algorithm provides an effective reduction of the decomposition of difference polynomials to the decomposition of linear difference polynomials over the same coefficient field. The algorithm is implemented in Maple for the constant coefficient case. Experimental results show that the algorithm is quite effective and can be used to decompose difference polynomials with thousands of terms.
A Question Answer System for Legal Information Retrieval
Authors: Paulo Quaresma, Irene Pimenta Rodrigues
Venue: Proceeding of the 2005 conference on Legal Knowledge and Information Systems: JURIX 2005: The Eighteenth Annual Conference (2005)

In this paper we present a question-answering system for Portuguese juridical documents. The system has two modules: preliminary analysis of documents (information extraction) and query processing (information retrieval). The proposed approach is based on computational linguistic theories: syntactical analysis (constraint grammars); followed by semantic analysis using the discourse representation theory; and, finally, a semantic/pragmatic interpretation using ontologies and logical inference. Knowledge representation and ontologies are handled through the use of an extension to PROLOG, ISCO, which allows to integrate logic programming and external databases. In this way it is possible to solve scalability problems like the need to represent more than 10 millions of discourse entities. The system was evaluated with the complete set of decisions from several Portuguese juridical institutions (Supreme Courts, High Court, Courts, and Attorney-General's Office) in a total of 180,000 documents. The obtained results were quite interesting and motivating and allowed the identification of some strong and weak characteristics of the system.
Reasoning with Inconsistencies in Propositional Peer-to-Peer Inference Systems
Authors: Ph. Chatalic, G. H. Nguyen, M. Ch. Rousset
Venue: Proceeding of the 2006 conference on ECAI 2006: 17th European Conference on Artificial Intelligence August 29 -- September 1, 2006, Riva del Garda, Italy (2006)

In a peer-to-peer inference system, there is no centralized control or hierarchical organization: each peer is equivalent in functionality and cooperates with other peers in order to solve a collective reasoning task. Since peer theories model possibly different viewpoints, even if each local theory is consistent, the global theory may be inconsistent. We exhibit a distributed algorithm detecting inconsistencies in a fully decentralized setting. We provide a fully distributed reasoning algorithm, which computes only well-founded consequences of a formula, i.e., with a consistent set of support.