pinecone/core-2020-05-10-deduplication huggingface dataset:
Verifying Monadic Second-Order Properties of Graph Programs

The core challenge in a Hoare- or Dijkstra-style proof system for graph
programs is in defining a weakest liberal precondition construction with
respect to a rule and a postcondition. Previous work addressing this has
focused on assertion languages for first-order properties, which are unable to
express important global properties of graphs such as acyclicity,
connectedness, or existence of paths. In this paper, we extend the nested graph
conditions of Habel, Pennemann, and Rensink to make them equivalently
expressive to monadic second-order logic on graphs. We present a weakest
liberal precondition construction for these assertions, and demonstrate its use
in verifying non-local correctness specifications of graph programs in the
sense of Habel et al.Comment: Extended version of a paper to appear at ICGT 201
Branch and bound based coordinate search filter algorithm for nonsmooth nonconvex mixed-integer nonlinear programming problems

Publicado em "Computational science and its applications – ICCSA 2014...", ISBN 978-3-319-09128-0. Series "Lecture notes in computer science", ISSN 0302-9743, vol. 8580.A mixed-integer nonlinear programming problem (MINLP) is a problem with continuous and integer variables  and  at least, one nonlinear function. This kind of problem appears in a wide range of real applications and is very difficult to solve. The difficulties are due to the nonlinearities of the functions in the problem and the integrality restrictions on some variables. When they are nonconvex then they are the most difficult to solve above all. We present a methodology to solve nonsmooth nonconvex MINLP problems based on a branch and bound paradigm and a stochastic strategy. To solve the relaxed subproblems at each node of the branch and bound tree search, an algorithm based on a multistart strategy with a coordinate search filter methodology is implemented. The produced numerical results show the robustness of the proposed methodology.This work has been supported by FCT (Fundação para a Ciência e aTecnologia) in the scope of the projects: PEst-OE/MAT/UI0013/2014 and PEst-OE/EEI/UI0319/2014
A global optimization approach applied to structural dynamic updating

In this paper, the application of stochastic global optimization tech- niques, in particular the GlobalSearch and MultiStart solvers from MatLab®, to improve the updating of a structural dynamic model, are presented. For com- parative purposes, the efficiency of these global methods relatively to the local search method previously used in a Finite Element Model Updating program is evaluated. The obtained solutions showed that the GlobalSearch and MultiStart solvers are able to achieve a better solution than the local solver previously used, in the updating of a structural dynamic model. The results show also that the GlobalSearch solver is more efficient than the MultiStart, since requires less computational effort to obtain the global solution.Fundação para a Ciência e a Tecnologia (FCT
Experiments with firefly algorithm

Firefly Algorithm (FA) is one of the recent swarm intelligence methods developed by Xin-She Yang in 2008 [12]. FA is a stochastic, nature-inspired, meta- heuristic algorithm that can be applied for solving the hardest optimization problems. The main goal of this paper is to analyze the influence of changing some parameters of the FA when solving bound constrained optimization problems. One of the most important aspects of this algorithm is how far is the distance between the points and the way they are drawn to the optimal solution. In this work, we aim to analyze other ways of calculating the distance between the points and also other functions to com- pute the attractiveness of fireflies.  To show the performance of the proposed modified FAs a set of 30 benchmark global optimization test problems are used.  Preliminary experiments reveal that the obtained results are competitive when comparing with the original FA version.Fundação para a Ciência e a Tecnologia (FCT
IMRT beam angle optimization using electromagnetism-like algorithm

The selection of appropriate beam irradiation directions in radiotherapy – beam angle optimization (BAO) problem – is very impor- tant for the quality of the treatment, both for improving tumor irradia- tion and for better organs sparing. However, the BAO problem is still not solved satisfactorily and, most of the time, beam directions continue to be manually selected in clinical practice which requires many trial and error iterations between selecting beam angles and computing ﬂuence patterns until a suitable treatment is achieved. The objective of this pa- per is to introduce a new approach for the resolution of the BAO problem, using an hybrid electromagnetism-like algorithm with descent search to tackle this highly non-convex optimization problem. Electromagnetism- like algorithms are derivative-free optimization methods with the ability to avoid local entrapment. Moreover, the hybrid electromagnetism-like algorithm with descent search has a high ability of producing descent directions. A set of retrospective treated cases of head-and-neck tumors at the Portuguese Institute of Oncology of Coimbra is used to discuss the beneﬁts of the proposed algorithm for the optimization of the BAO problem.Fundação para a Ciência e a Tecnologia (FCT
An agent-based model as a tool of planning at a sub-regional scale

This paper describes an agent-based model developed to simulate the impact that different planning policies may have in enhancing the attractiveness of the industrial estates located in a network of four municipalities located in the North of Portugal. The policies were simulated using three scenarios that can be distinguished by the municipal level of coordination they are implemented and by the type of action performed. In the model, enterprises are agents looking for a suitable location and the estates attractiveness is based on their level of facilities, amenities, accessibility and in the cost of soil. The coordinated qualification of the industrial estates is the most effective policy to strengthen their attractiveness. It was in this scenario that more industrial estates become attractive and more enterprises relocated. Results also indicate that the promotion of diffused and unqualified industrial estates is an inefficient policy to attract enterprises.Portuguese Foundation for Science and Technology (SFRH/BD/48567/2008 grant
If appleseed had an open portal : making sense of data, SEIS and integrated systems for the Maltese Islands

Much sought and realistically distant, an open data system can serve as the Holy Grail for many a policy-maker and decision taker as well as the operational entities involved in the field. The steady seeding of data-related legislative tools has aided the setting up of exploratory and active systems that serve the concept of data-information-knowledge-action to academia, the general public and the implementing agencies. Legislation, inclusive of Data Protection, Freedom of Information, Public Sector Information, Aarhus, INSPIRE, SEIS and the still embryonic SENSE, have all managed to create a new reality that may be too complex for some still caught in a jurassic analogue stage where data hoarding might still be prevalent and little effort is made to jump to the post-modern reality. Efforts to push the process through various domains such as census, environment protection, spatial development and crime have helped the Maltese Islands to create a scenario that is ripe for a national data infrastructure, inter-entity data exchange, open data structuring, and free dissemination services. This process enhances the knowledge-base and reduces redundancy, whilst creating new challenges on how to make sense of all the data being made available, particularly in the interpretation or misinterpretation of the outputs. The paper reviews Malta’s process to go through the birth pains of SEIS as an open data construct, through to the dissemination of various spatial datasets and the first open portals pertaining to the various regulatory directives.peer-reviewe
Modified quaternion Newton methods

We revisit the quaternion Newton method for computing roots of a class of quaternion valued functions and propose modified algorithms for finding  multiple  roots of simple polynomials. We illustrate the performance of these new methods by presenting several numerical experiments.The research was partially supported by the Research Centre of Mathematics of the University of Minho with the Portuguese Funds from the " Fundcao para a Ciencia e a Tecnologia", through the Project PEstOE/ MAT/ UI0013/ 2014
The screen representation of vector coupling coefficients or Wigner 3j
  symbols: exact computation and illustration of the asymptotic behavior

The Wigner $3j$ symbols of the quantum angular momentum theory are related to
the vector coupling or Clebsch-Gordan coefficients and to the Hahn and dual
Hahn polynomials of the discrete orthogonal hyperspherical family, of use in
discretization approximations. We point out the important role of the Regge
symmetries for defining the screen where images of the coefficients are
projected, and for discussing their asymptotic properties and semiclassical
behavior. Recursion relationships are formulated as eigenvalue equations, and
exploited both for computational purposes and for physical interpretations.Comment: 14 pages, 8 figures, presented at ICCSA 2014, 14th International
  Conference on Computational Science and Application
Removing inefficiencies from scientific code : the study of the Higgs boson couplings to top quarks

Publicado em "Computational science and its applications – ICCSA 2014 : proceedings", Series :  Lecture notes in computer science, vol. 8582This paper presents a set of methods and techniques to remove inefficiencies in a data analysis application used in searches by the ATLAS Experiment at the Large Hadron Collider. Profiling scientific code helped to pinpoint design and runtime inefficiencies, the former due to coding and data structure design. The data analysis code used by groups doing searches in the ATLAS Experiment contributed to clearly identify some of these inefficiencies and to give suggestions on how to prevent and overcome those common situations in scientific code to improve the efficient use of available computational resources in a parallel homogeneous platform.This work is funded by National Funds through the FCT - Fundaçãoo para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project PEst-OE/EEI/UI0752/2014, by LIP (Laborat ́orio de Instrumentação e Física Experimental de Partículas), and the SeARCH cluster (REEQ/443/EEI/2005)
Two high-performance alternatives to ZLIB scientific-data compression

ZLIB is used in diverse frameworks by the scientific community, both to reduce disk storage and to alleviate pressure on I/O. As it becomes a bottleneck on multi-core systems, higher throughput alternatives must be considered, exploring parallelism and/or more effective compression schemes. This work provides a comparative study of the ZLIB, LZ4 and FPC compressors (serial and parallel implementations), focusing on CR, bandwidth and speedup. LZ4 provides very high throughput (decompressing over 1GB/s versus 120MB/s for ZLIB) but its CR suffers a degradation of 5-10%. FPC also provides higher throughputs than ZLIB, but the CR varies a lot with the data. ZLIB and LZ4 can achieve almost linear speedups for some datasets, while current implementation of parallel FPC provides little if any performance gain. For the ROOT dataset, LZ4 was found to provide higher CR, scalability and lower memory consumption than FPC, thus emerging as a better alternative to ZLIB.This work is funded by National Funds through the FCT Fundacao para a Ciencia e a Tecnologia (Portuguese Foundation for Science and Technology) within project PEst-OE/EEI/UI0752/2014, UT Austin - Portugal FCT grant SFRH/ BD/47840/2008, and the resources from the project SeARCH funded under contract CONC- REEQ/443/2005. We would also like to thank Nuno Castro and Rafael Silva for their contributions
Forecasting household packaging waste generation : a case study

Nowadays, house packaging waste (HPW) materials acquired a great deal of importance, due to environmental and economic reasons, and therefore waste collection companies place thousands of collection points (ecopontos) for people to deposit their HPW.
In order to optimize HPW collection process, accurate forecasts of the waste generation rates are needed.
Our objective is to develop forecasting models to predict the number of collections per year required for each ecoponto by evaluating the relevance of ten proposed explanatory factors for HPW generation.
We developed models based on two approaches: multiple linear regression and artificial neural networks (ANN).The results obtained show that the best ANN model, which achieved an R 2 of 0.672 and MAD of 9.1, slightly outperforms the best regression model (R 2 of 0.636, MAD of 10.44).
The most important factors to estimate HPW generation rates are related to ecoponto characteristics and to the population and economic activities around each ecoponto location.Fundação para a Ciência e a Tecnologia (FCT
Accommodating Maternal Age in CRIB Scale: Quantifying the Effect on the Classification

Receiver operating characteristic (ROC) curves are a well-accepted measure of accuracy of diagnostic tests using in continuous or ordinal markers. Based on the notion of using a threshold to classify subjects as positive (diseased) or negative (no diseased), a ROC curve is a plot of the true positive fraction (TPF) versus the false positive fraction (FPF) for all possible cut points. Thus, it describes the whole range of possible operating characteristic for the test and hence its inherent capacity for distinguish between two status. The clinical severity scale CRIB - Clinical Risk Index for Babies, emerged in 1993 to predict the mortality of newborn at less than 32 weeks of gestation and very low birth weight (< 1500gr) [4]. In previous work of Braga [3] this index was reported as showing a good performance in assessing risk of death for babies with very low birth weight (less than 1500 g weight). However, in some situations, the performance of the diagnostic test, the ROC curve itself and the Area Under the Curve(AUC) can be strongly influenced by the presence of covariates, whether continuous or categorical [5], [32], [33]. The World Health Organization and the Ministry of Health, defined as "late pregnancy" that thus occurs in women over 35 years. In this work, using the conditional ROC curve, we analyze the effect of one covariate, maternal age, on the ROC curve that representing the diagnostic test performance. We chose two age status, less than 35 years old and equal or greater than 35 years old, to verify the effects on the discriminating power of CRIB scale, in the process classification using R and STATA software.info:eu-repo/semantics/publishedVersio
Degradation prediction model for friction in highways

The purpose of this paper is to develop a multiple linear regression model that describes the pavement’s friction behaviour using a degradation evo- lution law that also considers the effects of weather, vertical alignment and traf- fic factors. This study is based on real data obtained from two different highways with an approximate total length of 43 km. These sections present different alignment features (plan/profile), different Annual Average Daily Traffic and are subject- ed to different weather conditions. Nevertheless, both comprise the same type of upper layer.  The efficiency of the linear regression model in approaching and explaining da- ta was demonstrated. The most relevant factors involved in the degradation pro- cess of pavements’ friction were identified.Fundação para a Ciência e a Tecnologia (FCT
Towards Prospective Life Cycle Assessment: How to Identify Key Parameters Inducing Most Uncertainties in the Future? Application to Photovoltaic Systems Installed in Spain

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-09150-1_51International audienceProspective Life Cycle Assessment (LCA) is a relevant approach to assess the environmental performance of future energy pathways. Amongst different types of prospective scenarios, cornerstone scenarios meant for complex systems and long-term approaches, are of interest to assess such performance. They rely on different types of long-term projections, such as projections of technological evolutions and of energy resources. In most studies, scenarios are defined with single values for each parameter, and environmental impacts are assessed in a deterministic way. Inherent uncertainties related to these prospective assumptions are not considered and prospective LCA uncertainties are thus not addressed. In this paper we describe a methodology to account for these uncertainties and to identify the parameters inducing most of the uncertainties in the prospective LCA results. We apply this approach to prospective LCAs of photovoltaic-based electricity generation systems
The modelery: a collaborative web based repository

Software development processes are known to produce a large set of artifacts such as models, code and documentation. Keeping track of these artifacts without supporting tools is not easy, and making them available to others can be even harder. Standard version control systems are not able to solve this issue. More than keeping track of versions, a system to help organize and make artifacts available in meaningful ways is needed. In this paper we review a number of alternative systems, and present the requirements and the implementation of a collaborative web repository which we developed to solve this issue.Project LATiCES: Languages And Tools for Critical rEal-time Systems (Ref. NORTE-07-0124-FEDER-000062)
is financed by the North Portugal Regional Operational Programme (ON.2 - O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF), and by national funds, through the Portuguese funding agency, Fundacão para a Ciência e a Tecnologia (FCT)
Characterizing the control logic of web applications’ user interfaces

In order to develop an hybrid approach to the Reverse Engineer
of Web applications, we need first to understand how much of the
control logic of the user interface can be obtained from the analysis of
event listeners. To that end, we have developed a tool that enables us
to perform such analysis, and applied it to the implementation of the
one thousand most widely used Websites (according to Alexa Top Sites).
This paper describes our approach for analyzing the user interface layer
of those Websites, and the results we got from the analysis. The conclusions
drawn from the exercise will be used to guide the development of
the proposed hybrid reverse engineering tool.This work was partly funded by project LATiCES (Ref. NORTE-07-0124-FEDER-000062) financed by the North Portugal Regional Operational Programme (ON.2 – O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF), and by national funds, through the Portuguese funding agency, Fundação para a Ciência e a Tecnologia (FCT). Carlos Eduardo Silva is further funded by the Portuguese Government through FCT, grant SFRH/BD/71136/2010
Link prediction in online social networks using group information

Users of online social networks voluntarily participate in different user groups or communities. Researches suggest the presence of strong local community structure in these social networks, i.e., users tend to meet other people via mutual friendship. Recently, different approaches have considered communities structure information for increasing the link prediction accuracy. Nevertheless, these approaches consider that users belong to just one community. In this paper, we propose three measures for the link prediction task which take into account all different communities that users belong to. We perform experiments for both unsupervised and supervised link prediction strategies. The evaluation method considers the links imbalance problem. Results show that our proposals outperform state-of-the-art unsupervised link prediction measures and help to improve the link prediction task approached as a supervised strategy.São Paulo Research Foundation (FAPESP) (grants 2011/22749-8 and 2013/12191-5)National Council for Scientific and Technological Development (CNPq) (grant 151836/2013-2)14th International Conference on Computational Science and its Applications (ICCSA).\ud
Guimarães, Portugal. 30 June - 3 July 2014
Estimating and controlling the traffic Impact of a collaborative P2P system

Nowadays, P2P applications are commonly used in the Internet being an important paradigm for the development of distinct services. However, the dissemination of P2P applications also entails some important challenges that should be carefully addressed. In particular, some of the important coexistence problems existing between P2P applications and Internet Service Providers (ISPs) are mainly motivated by the inherent P2P dynamics which cause traffic to scatter across the network links in an unforeseeable way.
In this context, this work proposes a collaborative framework of a Bit- Torrent like system. Using the proposed framework and based on the exchange of valuable information between the application and network levels, some novel techniques are proposed allowing to estimate and control the traffic impact that the P2P system will have on the links of the underlying network infrastructure. Both the framework and the presented techniques were tested resorting to simulation. The results clearly corroborate the viability and effectiveness of the formulated methods
Conclave: ontology-driven measurement of semantic relatedness between source code elements and problem domain concepts

Software maintainers are often challenged with source code changes to improve software systems, or eliminate defects, in unfamiliar programs. To undertake these tasks a sufficient understanding of the system (or at least a small part of it) is required. One of the most time consuming tasks of this process is locating which parts of the code are responsible for some key functionality or feature. Feature (or concept) location techniques address this problem. This paper introduces Conclave, an environment for software analysis, and in particular the Conclave-Mapper tool that provides a feature location facility. This tool explores natural language terms used in programs (e.g. function and variable names), and using textual analysis and a collection of Natural Language Processing techniques, computes synonymous sets of terms. These sets are used to score relatedness between program elements, and search queries or problem domain concepts, producing sorted ranks of program elements that address the search criteria, or concepts. An empirical study is also discussed to evaluate the underlying feature location technique.info:eu-repo/semantics/publishedVersio
Using the NIST reference model for refining logical architectures

The emergence of the Internet as a ubiquitous means of communication fostered the growth of new business and service models based on Cloud Computing. Information and Communication Technology companies use reference models to define their Cloud Computing strategies. NIST Cloud Computing Reference Architecture is one of these reference models that assist in the design of business, services, and architecture models. This paper aims to present the use of NIST reference architecture in the design of Cloud Computing architectures by employing a method that enables the application of the reference architecture to the refinement of logical architectures. © 2014 Springer International Publishing