ppxscal/embedding_network huggingface dataset:
Scaling up support vector machines
Authors: James T. Kwok
Venue:  (2007)

Kernel methods, such as support vector machines (SVMs), have been successfully used in various aspects of machine learning problems, such as classification, regression, and ranking. Many of them are formulated as quadratic programming (QP) problems, which take O(m3) time and O(m2) space complexities, where m is the training set size. It is thus computationally infeasible on massive data sets. By observing that practical SVM implementations only approximate the optimal solution by an iterative strategy, I scale up kernel methods by exploiting such "approximateness" in this thesis. First, I show that SVM classification problems can be equivalently formulated as minimum enclosing ball (MEB) problems in computational geometry. Then, by adopting an efficient approximate MEB algorithm, I obtain provably approximately optimal solutions with the idea of core-sets. My proposed Core Vector Machine (CVM) algorithm can be used with nonlinear kernels and has a time complexity that is linear in m and a space complexity that is independent of m for a fixed approximation factor (1 + &epsi;) 2. Experiments on large real-world data sets demonstrate that the CVM is as accurate as existing SVM implementations but is much faster and can handle much larger data sets than existing scale-up methods. By generalizing the underlying MEB problem as the center-constrained minimum enclosing ball (CCMEB) problem, I extend the CVM algorithm to the regression and ranking setting. Moreover, the condition on the kernel function is relaxed. Thus, the enhanced CVM algorithm can be used with any linear/nonlinear kernels. Finally, I introduce the enclosing ball (MEB) problem where the ball's radius is fixed and thus does not have to be minimized. I develop efficient (1 + &epsi;)- approximation algorithms that are simple to implement and do not require any sophisticated numerical solver. For the Gaussian kernel in particular, a suitable choice of this (fixed) radius is easy to determine, and the center obtained from the (1+&epsi;)-approximation of this EB problem is close to the center of the corresponding MEB. Experimental results show that the proposed algorithm has accuracies comparable to the other large-scale SVM implementations, but can handle very large data sets and is even faster than the CVM in general.
Potential Role of FDG-PET Imaging in Defining Biology of Primary Breast Lesions
Authors: S. Basu, A. Mavi, T. Cermik, R. Kumar, A. Alavi
Venue: Proceedings of the 9th international workshop on Digital Mammography (2008)

FDG-PET in the evaluation and management of cancer patients continues to increase, but its precise role in the management of breast carcinoma is yet to be clearly defined. This study investigated the utility of FDG- PET imaging features in defining biology of primary breast lesions. Patients with newly diagnosed breast carcinoma underwent multimodality imaging techniques, such as MRI, ultrasonography, digital mammography, CT, and 18F-FDG PET. Breast lesions were imaged twice at 63 minutes and 101 minutes. Maximum standardized uptake values were measured at both time points to analyze the data generated. The percent change in the SUVs between the 2 time points was calculated. Unifactorial ANOVA of the three parameters among the primary lesions of these three groups were statistically significant for the mean SUVmax1 (p = 0.01) and SUVmax2 (p = 0.01). These values in the primary lesions were highest in those with both axillary and distant metastases, followed by those with only metastatic axillary adenopathy and patients without any metastasis. SUV measurements may provide valuable information about characterization of tumor biology. Such an association may be of importance to characterize and prognosticate the disease in these patients.
Women and gender in ict statistics and indicators for development
Authors: Nancy J. Hafkin, Sophia Huyer
Venue: Information Technologies and International Development (2008)

Issues related to the gender digital divide have been prominent in discussions of the information society. However, the paucity of statistical data on the subject makes it difficult, if not impossible, to make the case for the inclusion of gender issues in ICT policies, plans, and strategies to policymakers, particularly those in developing countries. This paper surveys available gender ICT statistics and indicators and makes recommendations for filling the gaps that exist. Few gender ICT statistics are available because many governments do not collect ICT statistics consistently and regularly, and rarely are the data disaggregated by sex. The best practices are generally found in developed countries, with most developing countries lagging behind. Recent work that sheds light on women, gender, and the information society includes a major six-country study on the gender digital divide in francophone countries of West Africa and Orbicom's 2005 research on women in the information society. Although major composite ICT indices do not publish gender and ICT statistics, the potential remains for them to do so, and some indices encourage others to enrich their work with gender data.
Pseudo-Random Bit Generation Based on 2D Chaotic Maps of Logistic Type and Its Applications in Chaotic Cryptography
Authors: C. Pellicer-Lostao, R. López-Ruiz
Venue: Proceedings of the international conference on Computational Science and Its Applications, Part II (2008)

Pseudo-Random Bit Generation (PRBG) is required in many aspects of cryptography as well as in other applications of modern security engineering. In this work, PRBG based on 2D symmetrical chaotic mappings of logistic type is considered. The sequences generated with a chaotic PRBG of this type, are statistically tested and the computational effectiveness of the generator is estimated. Considering this PRBG valid for cryptography, the size of the available key space is also calculated. Different cryptographic applications can be suitable to this PRBG, being a stream cipher probably the most immediate of them.
On periodic solutions of differential equations with piecewise constant argument
Authors: M. U. Akhmet, C. Büyükadalı
Venue: Computers Mathematics with Applications (2008)

The periodic quasilinear system of differential equations with small parameter and piecewise constant argument of generalized type [M.U. Akhmet, Integral manifolds of differential equations with piecewise constant argument of generalized type, Nonlinear Anal. TMA, 66 (2007) 367-383, M.U. Akhmet, On the reduction principle for differential equations with piecewise argument of generalized type, J. Math. Anal. Appl. 336 (2007) 646-663] is addressed. We consider the critical case, when associated linear homogeneous system admits nontrivial periodic solutions. Criteria of existence of periodic solutions of such equations are obtained. One of the main auxiliary results of our paper is an analogue of Gronwall-Bellman Lemma for functions with piecewise constant and retarded-advanced type arguments. Dependence of solutions on the parameter is investigated. Appropriate examples are given to show our results.
The Seventies
Authors: Alberto Martelli
Venue: Concurrency, Graphs and Models: Essays Dedicated to Ugo Montanari on the Occasion of His 65th Birthday (2008)

I arrived in Pisa at the beginning of 1968, after getting my degree from the Politecnico of Milan. At that time Antonio Grasselli was moving from the Politecnico of Milan to organize the new curriculum in Computer Science at the University of Pisa, and wanted to create a research group there. The group was established at the Istituto di Elaborazione dell'Informazione (IEI) of the National Research Council, and included initially Giorgio Levi, Ugo Montanari, Franco Sirovich and myself.The initial research activities of the group were in the area of image processing, but, after a couple of years, the group, which in the meantime had been joined by Gigina Carlucci Aiello, decided to modify its main research topic. Our conclusion was that Artificial Intelligence was a new and more challenging area, allowing to combine theoretical aspects with problems of practical interest, and we started to redirect our research towards the topic. In those years, all of us spent long periods in the USA, and this gave us an up-to-date view of the main research themes, and allowed to establish international contacts.
Product Based Workflow Support: Dynamic Workflow Execution
Authors: Irene Vanderfeesten, Hajo A. Reijers, Wil M. Aalst
Venue: Proceedings of the 20th international conference on Advanced Information Systems Engineering (2008)

Product Based Workflow Design (PBWD) is a successful new approach to workflow process support. A description of the product, the Product Data Model (PDM), is central to this approach. While other research so far has focused on deriving a process model from the PDM, this paper presents a way to directly execute the PDM. This leads to a more dynamic and flexible support for the workflow process.
A Lightweight Approach for Defining the Formal Semantics of a Modeling Language
Authors: Pierre Kelsen, Qin Ma
Venue: Proceedings of the 11th international conference on Model Driven Engineering Languages and Systems (2008)

To define the formal semantics of a modeling language, one normally starts from the abstract syntax and then defines the static semantics and dynamic semantics. Having a formal semantics is important for reasoning about the language but also for building tools for the language. In this paper we propose a novel approach for this task based on the Alloy language. With the help of a concrete example language, we contrast this approach with traditional methods based on formal languages, type checking, meta-modeling and operational semantics. Although both Alloy and traditional techniques yield a formal semantics of the language, the Alloy-based approach has two key advantages: a uniform notation, and immediate automatic analyzability using the Alloy analyzer. Together with the simplicity of Alloy, our approach offers the prospect of making formal definitions easier, hopefully paving the way for a wider adoption of formal techniques in the definition of modeling languages.
Integrating Component and Product Lines Technologies
Authors: Elder Cirilo, Uirá Kulesza, Roberta Coelho, Carlos J. Lucena, Arndt Staa
Venue: Proceedings of the 10th international conference on Software Reuse: High Confidence Software Reuse in Large Systems (2008)

In this paper, we explore the integration of product line and component technologies in the context of the product derivation process. In particular, we propose new extensions to our existing model-based product derivation tool, called GenArch, in order to address the new abstractions and mechanisms provided by the Spring and OSGi component models. The GenArch extensions enable the automatic instantiation of product lines and applications - implemented using these component technologies. Moreover, it also enables different levels of customization, from fine-grained configuration of component properties to the automatic selection of components that will compose the final product.
Encodings of Bounded LTL Model Checking in Effectively Propositional Logic
Authors: Juan Antonio Navarro-Pérez, Andrei Voronkov
Venue: Proceedings of the 21st international conference on Automated Deduction: Automated Deduction (2007)

We present an encoding of LTL bounded model checking problems within the Bernays-Schönfinkel fragment of first-order logic. This fragment, which also corresponds to the category of effectively propositional problems (EPR) of the CASC system competitions, allows a natural and succinct representation of both a software/hardware system and the property that one wants to verify.The encoding for the transition system produces a formula whose size is linear with respect to its original description in common component description languages used in the field (e.g. smv format) preserving its modularity and hierarchical structure. Likewise, the LTL property is encoded in a formula of linear size with respect to the input formula, plus an additional component, with a size of O(logk) where k is the bound, that represents the execution flow of the system.The encoding of bounded model checking problems by effectively propositional formulae is the main contribution of this paper. As a side effect, we obtain a rich collection of benchmarks with close links to real-life applications for the automated reasoning community.
Hybrid Systems and Artificial Immune Systems: Performances and Applications to Biomedical Research
Authors: Vitoantonio Bevilacqua, Cosimo G. Musso, Filippo Menolascina, Giuseppe Mastronardi, Antonio Pedone
Venue: Proceedings of the 4th international symposium on Neural Networks: Part II--Advances in Neural Networks (2007)

In this paper we propose a comparative study of Artificial Neural Networks (ANN) and Artificial Immune Systems. Artificial Immune Systems (AIS) represent a novel paradigm in the field of computational intelligence based on the mechanisms that allow vertebrate immune systems to face attacks from foreign agents (called antigens). Several similarities as well as differences have been shown by Dasgupta in [1]. Here we present a comparative study of these two approaches considering evolutions of the concepts of ANN and AIS, respectively hybrid neural systems, Artificial Immune Recognition Systems (AIRS) and aiNet. We tried to establish a comparison among these three methods using a well known dataset, namely the Wisconsin Breast Cancer Database. We observed interesting trends in systems' performances and capabilities. Peculiarities of these systems have been analyzed, possible strength points and ideal contexts of application suggested. These and other considerations will be addressed in the rest of this manuscript.
Estimating Hybrid Frequency Moments of Data Streams
Authors: Sumit Ganguly, Mohit Bansal, Shruti Dube
Venue: Proceedings of the 2nd annual international workshop on Frontiers in Algorithmics (2008)

A two-dimensional stream is a sequence of coordinate-wise updates to a two-dimensional array (A i,j )1 ≤ i,j ≤ n . The hybrid frequency moments F p,q (A) is defined as . For every 0 < ¿< 1 and p,q ¿ [0,2], we present an $O(\epsilon^{-6} \text{poly}(\log n, \log m, \log (1/\epsilon)))$ space algorithm for the problem of estimating F p,q , where, m is an upper bound on .
Enabling Accurate Node Control in Randomized Duty Cycling Networks
Authors: Kang-Won Lee, Vasileios Pappas, Asser Tantawi
Venue: Proceedings of the 2008 The 28th International Conference on Distributed Computing Systems (2008)

In this paper, we propose a novel duty cycling algorithm for a large-scale dense wireless sensor networks. The proposed algorithm is based on a social behavior of nodes in the sense that individual node's sleep/wakeup decision is influenced by the state of its neighbors. We analyze the behavior of the proposed duty cycling algorithm using a stochastic spatial process. In particular, we consider a geometric form of neighborhood dependence and a reversible Markov chain, and apply this model to analyze the behavior of the duty cycling network. We then identify a set of parameters for the reversible spatial process model, and study the steady state of the network with respect to these parameters. We report that our algorithm is scalable to a large network, and can effectively control the active node density while achieving a small variance. We also report that the social behavior of nodes has interesting and non-obvious impacts on the performance of duty cycling. Finally, we present how to set the parameters of the algorithm to obtain a desirable duty cycling behavior.
An Industrial Case: Pitfalls and Benefits of Applying Formal Methods to the Development of a Network-Centric RTOS
Authors: Eric Verhulst, Gjalt Jong, Vitaliy Mezhuyev
Venue: Proceedings of the 15th international symposium on Formal Methods (2008)

This paper describes a project to develop a network-centric RTOS from scratch using formal methods. The (initial) purposes of the project was to get acquainted with the use of formal methods for software engineering and to obtain a trustworthy RTOS as a component for building networked embedded systems. The work was done by a small, distributed team that had no prior experience on using formal methods and with a small budget. The outcome is that the use of formal methods is most useful as an architectural design method, perhaps more than as a formal verification of software code. The resulting software has many properties that were not anticipated at the beginning and would likely not have been achieved without the use of Formal Methods.
An Indexed System for Multiplicative Additive Polarized Linear Logic
Authors: Masahiro Hamano, Ryo Takemura
Venue: Proceedings of the 22nd international workshop on Computer Science Logic (2008)

We present an indexed logical system MALLP( I) for Laurent's multiplicative additive polarized linear logic (MALLP) [14]. The system is a polarized variant of Bucciarelli-Ehrhard's indexed system for multiplicative additive linear logic [4]. Our system is derived from a web-based instance of Hamano-Scott's denotational semantics [12] for MALLP. The instance is given by an adjoint pair of right and left multi-pointed relations. In the polarized indexed system, subsets of indexes for I work as syntactical counterparts of families of points in webs. The rules of $\sf MALLP({\it I})$ describe (in a proof-theoretical manner) the denotational construction of the corresponding rules of MALLP. We show that $\sf MALLP({\it I})$ faithfully describes a denotational model of MALLP by establishing a correspondence between the provability of indexed formulas and relations that can be extended to (non-indexed) proof-denotations.
Anti-Patterns: Integrating Distributed and Heterogeneous Data Sources in SOAs
Authors: Hakan Hacigümüs
Venue: Proceedings of the 2008 IEEE Congress on Services - Part I (2008)

In computer science, anti-patterns are specific repeated practices that appear initially to be beneficial, but ultimately result in undesirable consequences that outweigh the expected advantages. In this article we present our experiences from a range of industrial projects where there is a strong need for integrating distributed and heterogeneous data sources. SOA approach is selected to achieve the integration goals. We present the problem and the common solution approach that has been repeatedly observed in the field. This common approach manifests itself as an anti-pattern since in many cases the solution produces unwanted outcomes. We outline the reasons for the failures and introduce a preferred solution to the same problem that we have successfully applied in many cases as an alternative to the so-called common approach.
Automatic generation of the optimum threshold for parameter weighted pruning in multiple heterogeneous output neural networks
Authors: A. Luchetta
Venue: Neurocomputing (2008)

In this paper a new procedure for the selection of pruning threshold in feedforward artificial neural networks (FANN) is presented. It is based on an evaluation of a local sensitivity index which has been previously calculated with respect to any single output of the network. Special emphasis has been given to a particular class of neural networks with multiple heterogeneous outputs. The effectiveness of the proposed method will be shown by the development of a neural architecture devoted to a specific multi-output inversion system. The proposed pruning technique provides criteria in deciding ''when'' and ''how much'' to prune the designed neural network.
The problem of the moody chess players
Authors: Fokko J. van de Bult, Gerhard J. Woeginger
Venue: Information Processing Letters (2008)

We analyze a sorting problem where for every element there is a hard upper bound on the overall number of lost comparisons: Given are n elements and n non-negative integers a"1,...,a"n. The goal is to sort these n elements by pairwise comparisons, subject to the condition that the kth element must not be the loser (= smaller element) in more than a"k of its comparisons against the other elements. We completely characterize the sequences a"1,...,a"n for which this sorting problem can be solved.
A Requirements-Driven and Collaborative Decision Support Approach for Evaluating the Viability of Candidate Implementation Technologies
Authors: Bradley Wehrwein, Gilberto Matos, Rajanikanth Tanikella
Venue: Proceedings of the 2008 12th International IEEE Enterprise Distributed Object Computing Conference (2008)

Platforms, frameworks, and other forms of software assets are proliferating in the industry for well-documented reasons. Architects may choose from a wide variety of implementation technologies to realize their envisioned software architecture. Each asset provides the ability to fulfill a set of requirements, and imposes a set of constraints. Given these complex compatibility relationships, it is a non-trivial task to determine how best to utilize candidate assets toward a defined business problem. This task is made harder when multiple stakeholders from various backgrounds contribute to the decision-making process, as often occurs in large projects.By grouping requirements by functional area, and relating them to corresponding candidate technologies, we propose an approach that allows stakeholders to collaboratively reason about the satisfaction of requirements, the compatibility of technologies, and integration risk. The goal is to narrow the initial space of technologies to a smaller number of viable candidate technology sets.
Variability Driven Quality Evaluation in Software Product Lines
Authors: Leire Etxeberria, Goiuria Sagardui
Venue: Proceedings of the 2008 12th International Software Product Line Conference (2008)

Variability is a key aspect in software product lines. Functional variability has been largely studied as a way to obtain all the desired products for a line. Quality variability, less understood and more complex, has not received so much attention by researchers. However, different members of the line may require different levels of a quality attribute. The design phase is a good point to assure that quality attributes requirements are met within the product line so this means paying attention to software architecture evaluation during Domain Engineering. The quality evaluation in software product lines is much more complicated than in single-systems as products can require different quality levels and the product line can have variability on design that in turn affects quality. The evaluation of all the products of a line is very expensive. Thus, ways of reducing the evaluation efforts are necessary. Herein is presented a method for facilitating cost-effective quality evaluation of a product line taking into consideration variability on quality attributes.