Normal Heat Conduction in a Chain with Weak Interparticle Anharmonic Potential

We analytically study heat conduction in a chain with interparticle interaction V(x)=lambda[1-cos(x)] and harmonic on-site potential. We start with each site of the system connected to a Langevin heat bath, and investigate the case of small coupling for the interior sites in order to understand the behavior of the system with thermal reservoirs at the boundaries only. We study, in a perturbative analysis, the heat current in the steady state of the one-dimensional system with weak interparticle potential. We obtain an expression for the thermal conductivity, compare the low and high temperature regimes, and show that, as we turn off the couplings with the interior heat baths, there is a "phase transition:'' the Fourier's law holds only at high temperatures

Non-equilibrium Statistical Mechanics of Anharmonic Crystals with Self-consistent Stochastic Reservoirs

We consider a d-dimensional crystal with an arbitrary harmonic interaction and an anharmonic on-site potential, with stochastic Langevin heat bath at each site. We develop an integral formalism for the correlation functions that is suitable for the study of their relaxation (time decay) as well as their behavior in space. Furthermore, in a perturbative analysis, for the one-dimensional system with weak coupling between the sites and small quartic anharmonicity, we investigate the steady state and show that the Fourier's law holds. We also obtain an expression for the thermal conductivity (for arbitrary next-neighbor interactions) and give the temperature profile in the steady state

Architecture based on keyword driven testing with domain specific language for a testing system

For Cyber-physical systems (CPSs), whose task is to test industrial products, to carry out these tests, highly qualified engineers are always needed to design the tests, since the computational part of the tests is programmed in low-level languages. To optimize this process, it is necessary to create an abstraction of current methods so that tests can be created and executed more efficiently. Although this problem has arisen within the CPS, the architecture we propose will be generic enough to solve the problem in any testing system. We intend to do this by automating some of the current processes to minimize human error. In this paper, we present a novel architecture for a testing system that abstracts single low-level programming and coding of tests, based on two main concepts: the use of Keyword Driven Testing (KDT) that will abstract tests to the person responsible for the machine; the creation of a Domain Specific Language (DSL) to help configure and design new tests without requiring the experience of a highly qualified engineer.This paper is a result of the project POCI-01-0247-FEDER-040130, supported by Operational Program for Competitiveness and Internationalization (COMPETE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF)

Board characteristics and compensation in Brazilian listed companies

This article suggests that larger, better-governed, and lower ownership concentration companies have less homogeneous and passive boards, but pay more to their senior managers and directors. These companies probably need better-paid professionals to cope with more complex compliance and business environments. We create two categorical variables named homogeneity (HS) and passivity (PS) scores that aggregate hand collected board member characteristics. More homogeneous and passive boards may grant larger director and senior management compensations under the managerial power hypothesis (BEBCHUK and FRIED, 2005). On the other hand, larger and value increasing companies may pay more to their senior managers (JENSEN and MURPHY, 1990). Our findings suggest that less homogeneous and passive boards grant larger compensations in univariate tests. These results, however, do not transpire in multivariate tests. More homogeneous and passive boards are more frequent in smaller and higher ownership concentration companies, with poorer corporate governance and disclosure practices. It is possible that financial disclosure practices are more important then board characteristics (LEAL and CARVALHAL-DA-SILVA, 2007). These results highlight the importance of disclosure and transparency efforts to improve investor relations and reduce the cost of capital in a high ownership concentration country.Este artigo sugere que empresas maiores, com melhores práticas de governança corporativa e menor concentração de direitos de propriedade têm conselhos de administração (CA) menos homogêneos e passivos, mas pagam mais a sua diretoria e conselheiros. Essas empresas provavelmente precisam de profissionais mais bem pagos para lidar com ambientes de conformidade e de negócios mais complexos. Nós criamos duas variáveis categóricas chamadas de pontuações de homogeneidade e passividade que agregam dados colhidos a mão sobre características dos membros do CA. CAs mais homogêneos e passivos podem conceder maiores remunerações para a diretoria e conselheiros sob a hipótese do poder gerencial (BEBCHUK e FRIED, 2005). Por outro lado, grandes empresas que agregam valor para os acionistas podem pagar mais a sua diretoria (JENSEN e MURPHY, 1990). Nossos resultados sugerem que os CA menos homogêneos e passivos concedem remunerações maiores em testes univariados. Estes resultados, no entanto, não surgem nos testes multivariados. CAs mais homogêneos e passivos são mais frequentes em empresas menores, com maior concentração de direitos de propriedade e práticas de governança corporativa e divulgação de informações piores. É possível que as práticas de divulgação financeira sejam mais importantes do que as características dos conselheiros (LEAL e CARVALHAL-DA-SILVA, 2007). Estes resultados destacam a importância dos esforços de divulgação e transparência para melhorar as relações com investidores e reduzir o custo de capital em um país com concentração de direitos de propriedade elevada

Erratum to: Designation of Natural Monuments by the Local Administration: the Example of Viana Do Castelo Municipality and its Engagement with Geoconservation (NW Portugal)

The original version of this article unfortunately contained a mistake. The four occurrences of the word “geopark” were incorrect and should be replaced with “geological park”

Development of self-diagnosis tests system using a DSL for creating new test suites for integration in a cyber-physical system

Testing Cyber-physical systems (CPS) requires highly qualified engineers to design the tests since its computational part is programmed in low-level languages. The origin of this work arises from the need to find a solution that optimizes this problem and allows abstracting the current methods so that the tests can be created and executed more efficiently. We intend to do this by creating a self-diagnosis tests system that allows us to automate some of the current processes in the creation and execution of test suites. The work presented here addresses the problem by creating a new self-diagnosis tests system that will guarantee the reliability and integrity of the CPS. In detail, this paper begins by exposing a study on the current state of the art of test automation, Keyword-driven Testing (KDT) methodology and Domain-specific Languages (DSL). A new modular and extensible architecture is proposed for self-diagnosis tests systems based on two main concepts: the creation of a DSL combined with the use of the KDT methodology, as well as a methodology to extend it and integrate it into a CPS. A new self-diagnosis tests system has been proposed that applies the proposed architecture proving that it is possible to carry out the self-diagnosis in real-time of the CPS and allowing the integration of any type of test. To validate the implementation of the system, 28 test cases were carried out to cover all its functionalities. The results show that all test cases passed and, therefore, the system meets all the proposed objectives.(undefined

Development of a self-diagnostic system integrated into a cyber-physical system

CONTROLAR provides Bosch with an intelligent functional testing machine used to test the correct functioning of the car radios produced. During this process, the radios are submitted to several tests, raising the problem of how the machine detects errors in several radios consecutively, making it impossible to know if the device has a problem since it has no module to see if it works correctly. This article arises from the need to find a solution to solve this problem, which was to develop a self-diagnostic system that will ensure the reliability and integrity of the cyber-physical system, passing a detailed state of the art. The development of this system was based on the design of an architecture that combines the KDT methodology with a DSL to manage and configure the tests to integrate the self-diagnostic test system into a CPS. A total of 28 test cases were performed to cover all its functionalities. The results show that all test cases passed. Therefore, the system meets all the proposed objectives.This article is a result of the project POCI-01-0247-FEDER-040130, supported by Operational Program for Competitiveness and Internationalization (COMPETE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF)

Electric field effects on β-lactoglobulin thermal unfolding as a function of pH Impact on protein functionality

The presence of moderate electric fields (MEF) during ohmic heating (OH) treatment of whey protein systems have demonstrated potential to change physicochemical and functional properties, like aggregation rate and extension or viscoelastic behaviour. However, the specific action of MEF upon the molecular structure of proteins, particularly during thermal processing has yet to be clarified. The effects of MEF in pure fractions of -lactoglobulin (β-lg) under non-aggregating conditions (low concentration and ionic strength), were investigated in this work. Protein samples were identically heat-treated through conventional and OH methods and at different pH values. β-lg's structural features were characterized by evaluation of secondary structure distribution and local conformational changes using techniques such as circular dichroism, intrinsic and extrinsic fluorescence and free thiol groups reactivity. It was confirmed that MEF affects β-lg upon thermal unfolding, resulting in distinctive structural features, surface hydrophobicity and SH reactivity. The mechanism of action is probably related with the molecular motion induced by the oscillating electric field and is more pronounced at neutral pH, where β-lg is more susceptible to thermal structural changes. These results contribute to a better understanding of OH processing and its effects in food matrices reinforce the possibility of using MEF as a toll to change protein functionality. Industrial relevance Ohmic heating is an emerging technology and is being established as reference method for processing protein-rich food such as dairy and egg products. Non-thermal effects of the applied electric fields during ohmic heating have been addressed but few works deal with their real impact in structural and molecular properties of food proteins with high biological value. In this work demonstrated that the presence of an electric field during ohmic heating processing influences structural aspects of beta-lactoglobulin. This knowledge plays an important role on process design (i.e. pasteurization binomials and fouling control) and product quality because these proteins play an essential role in food's nutritional and organoleptic properties, as well as on functionality, allergenicity and stability aspects.FCT -Fuel Cell Technologies Program(NORTE-01-0145-FEDER-000004)info:eu-repo/semantics/publishedVersio

BayGO: Bayesian analysis of ontology term enrichment in microarray data

BACKGROUND: The search for enriched (aka over-represented or enhanced) ontology terms in a list of genes obtained from microarray experiments is becoming a standard procedure for a system-level analysis. This procedure tries to summarize the information focussing on classification designs such as Gene Ontology, KEGG pathways, and so on, instead of focussing on individual genes. Although it is well known in statistics that association and significance are distinct concepts, only the former approach has been used to deal with the ontology term enrichment problem. RESULTS: BayGO implements a Bayesian approach to search for enriched terms from microarray data. The R source-code is freely available at in three versions: Linux, which can be easily incorporated into pre-existent pipelines; Windows, to be controlled interactively; and as a web-tool. The software was validated using a bacterial heat shock response dataset, since this stress triggers known system-level responses. CONCLUSION: The Bayesian model accounts for the fact that, eventually, not all the genes from a given category are observable in microarray data due to low intensity signal, quality filters, genes that were not spotted and so on. Moreover, BayGO allows one to measure the statistical association between generic ontology terms and differential expression, instead of working only with the common significance analysis