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Distributed thermal response tests using a heating cable and fiber optic temperature sensing
No full textThermal response tests are used to assess the subsurface thermal conductivity to design ground-coupled heat pump systems. Conventional tests are cumbersome and require a source of high power to heat water circulating in a pilot ground heat exchanger. An alternative test method using heating cable was verified in the field as an option to conduct this heat injection experiment with a low power source and a compact equipment. Two thermal response tests using heating cable sections and a continuous heating cable were performed in two experimental heat exchangers on different sites in Canada and France. The temperature evolution during the tests was monitored using submersible sensors and fiber optic distributed temperature sensing. Free convection that can occur in the pipe of the heat exchanger was evaluated using the Rayleigh number stability criterion. The finite and infinite line source equations were used to reproduce temperature variations along the heating cable sections and continuous heating cable, respectively. The thermal conductivity profile of each site was inferred and the uncertainly of the test was evaluated. A mean thermal conductivity 15% higher than that revealed with the conventional test was estimated with heating cable sections. The thermal conductivity evaluated using the continuous heating cable corresponds to the value estimated during the conventional test. The average uncertainly associated with the heating cable section test was 15.18%, while an uncertainty of 2.14% was estimated for the test with the continuous heating cable. According to the Rayleigh number stability criterion, significant free convection can occur during the heat injection period when heating cable sections are used. The continuous heating cable with a low power source is a promising method to perform thermal response tests and further tests could be carried out in deep boreholes to verify its applicability. © 2018 by the authors. Licensee MDPI, Basel, Switzerland
Social and Human Factor Classification of Influence in Productivity in Software Development Teams
No full textSoftware development organizations continuously seek to increase the productivity of their teams. However, productivity in the development of a software product is characterized by a high dependence on social and human factors. Therefore, studying these factors is essential to meet the performance needs of software development organizations. The above supports the motivation to consider the social and human factors that may influence the productivity of software development teams. This research has been conducted to classify such factors associated with the productivity of software development teams. For this purpose, a methodology was designed based on systematic literature review processes and evaluation processes with a psychology expert. The classification of social and human factors and their respective definitions are the partial results of this investigation. The proposed classification is an essential input for the establishment of improvement actions. © 2020, Springer Nature Switzerland AG
The origin of the high reactivity of triazolinediones (TADs) in Diels-Alder reactions from a theoretical perspective
No full textWe investigate on the origin of the high reactivity of triazolinediones compared to maleimides in Diels-Alder reactions by using a combination of Molecular Orbital Theory and the Activation Strain Model of reactivity. Calculations at M06-2X/6–311++G(d,p)//M06-2X/6-31+G(d) level show that the energy barrier of the cycloaddition between anthracene and triazolinedione is much lower than that for maleimides. The analysis of frontier molecular orbitals (FMO) reveals that for the TAD system there is a much efficient charge transfer as consequence of a more delocalized HOMO over the dienophile fragment at the transition state structure. The Activation Strain Model revealed that the higher reactivity of TAD in the cycloaddition is related to the lower distortion of both fragments to attain the geometry of the transition state. © 2020 Elsevier Lt
Validity of the instrument to determine the triggers of innovation capabilities in health care organizations [Validez del instrumento para determinar los detonantes de las capacidades de innovación en las organizaciones dedicadas al cuidado de la salud]
No full textThe proposal aims to validate an instrument that accounts for the predictors of innovation capabilities in healthcare organizations. Two techniques are accepted, one of them is the Exploratory Factor Analysis (AFE), and the other, the Confirmatory Factor Analysis (AFC). The sample consisted of 200 observations obtained from the network of high complexity hospitals in Colombia during 2016 and 2017. The research shows a valid instrument from its constructs and determinants (Knowledge Management, Human Resource Managament, Organizational Capabilities, Culture, and finally those associated with the Health Care Organizations). Furthermore, the results of the Confirmatory Factorial Analysis allowed to test the theoretical model. This type of initiative is pioneer for three reasons: 1) The application of the methods to the health sector; 2) the conceptual amplitude of a large number of internal predictors of the Innovation Capabilities and 3) the existence of some descriptive studies is detected, with special attention to innovation in a general way, but the intention of the present work goes far beyond the merely prescriptive works, tries to demonstrate by means of quantitative techniques the singularities of innovation capabilities in the health sector. © 2018 Academia Nacional de Medicina. All Rights Reserved
Not all platinum surfaces are the same: Effect of the support on fundamental properties of platinum adlayer and its implications for the activity toward hydrogen evolution reaction
No full textThe adsorption of atomic hydrogen on a platinum monolayer supported on orthorhombic Mo2C(100) surface has been investigated, considering different hydrogen surface coverages. Calculations have been performed using density functional theory with the Perdew–Burke–Ernzerhof exchange correlation functional and a D3 van der Waals corrections. The theoretical insight has been gained into atomic hydrogen interaction with Pt monolayer, supported on both molybdenum and well-studied tungsten carbide, and considering hydrogen surface coverage. Fundamental properties of Pt adlayer depend on the support, affecting hydrogen evolution activity of the resulting systems. At low hydrogen coverage all systems, with the exception of Pt supported on the molybdenum-terminated Mo2C, adsorb H comparably to a pristine Pt(111) surface and their high activity for the hydrogen evolution reaction is predicted. At higher coverages supported Pt monolayers interact with atomic hydrogen unlike the Pt(111), suggesting that the activity of the supported and unsupported platinum toward hydrogen evolution reaction have different origins. Furthermore, the position of the supported platinum monolayers on the volcano curve is a function of the surface coverage, more so than for extended metal surfaces. Therefore, hydrogen surface coverage is a key variable to understand the catalytic potential, approaching towards an improved model for screening of electrocatalytic systems. © 2020 Elsevier Lt
Spontaneous activation under atrial fibrosis: A model using complex order derivatives
No full textThe computational modeling of the cardiac electrophysiology allows assertive and quantitative study of the atrial fibrosis under fibrillation conditions. The cardiac electrical propagation is described by the so-called monodomain model, that consists of a nonlinear parabolic reaction-diffusion equation. Fibroblast proliferation, which is an essential component of the fibrotic process, can be modeled by considering the membrane ionic kinetics as a reactive component. However, such a mathematical description does not account the structural feature of fibroblasts. In this work, the electrophysiological properties of fibroblast proliferation and coupling with cardiomyocytes are investigated, using mathematical and computational modelling. The study is focused on the conditions under which spontaneous activations occur in a fibrotic domain. The proposed fibrosis model takes account the electrical and structural interactions of fibroblasts within the myocardium. The electrical component is described through an ionic kinetics formalism, while the structural component is obtained by means of a triplet of complex order derivatives that constructs the diffusion operator. A theoretical analysis determines the model parameters that generate unstable solutions, and numerical simulations illustrate and validate the analytical outcomes. The results evince a strong modulation of the stability conditions of the fibrotic model by the real and imaginary part of the fractional derivative order. The fibrosis structural complexity, controlled by the fractional order, determines the extent of the parameter space that generates spontaneous activation. Moreover, not all the unstable parameter configurations generate electrical propagation. In the cases of electrical conduction after spontaneous activation, the conduction velocity in the fibrotic domain is significantly slower than the one observed in healthy atrial tissue. The results give a new perspective for the development of atrial fibrosis models including the ectopic activity as an initiation factor for fibrillation activity. Indeed, the proposed design exploits the complex order fractional derivatives, to generate a wide set of electrophysiological scenarios. © 2020 Elsevier B.V
Strengthening the Leadership of Rites and Ceremonies for Reconciliation and Truth: The Case of Socorro Mosquera, Manager and Human Rights Defender in Colombia
No full textThis article proposes a tool to strengthen the leadership of rites and ceremonies for reconciliation and truth, using a multidisciplinary approach and bringing together political topics (reconciliation and truth), anthropological concepts (rites and ceremonies), and management sciences issues (leadership) in a special urban context that requires reconciliation and truth after a long, irregular war with multiple violations of human rights. After formulation of the research problem, we were able to relate reconciliation and truth with leadership, rites, and ceremonies. Once so related, we analyzed the historical evolution of rites and ceremonies, with special emphasis on the organizational context, to finally propose a tool to strengthen the leadership of rites and ceremonies for reconciliation and truth. The utility of this tool was confirmed in the case of Socorro Mosquera, a manager and human rights defender in Medellín, Colombia. The eclectic and integrative approach brings originality to the study, while the methodological application of mixed approaches increases its value. © 2019, © 2019 Taylor & Francis Group, LLC
Scientometric study of a co-authorship network on mathematics education. An analysis of the research fields based on Delphi method [Estudio cienciométrico de una red de coautoría en educación matemática. Un análisis de sus campos de investigación basado en el método Delphi]
No full textCo-authorhip networks indirectly express complex scientific collaboration processes that transcend the institutional and national spheres. This study is aimed to identify co-authorship networks in the field of mathematics education, in order to determine structural framework and research fields in one largely visible network. Bibliometric methods are used, based on 8577 documents registered in Scopus (period 1969-2018), supported by co-authoring networks to identify the groups with the greatest direct or indirect activity. The Delphi method is also used with a panel of 21 experts at two rounds, in order to determine the respective research fields. The study reveals an accelerated growth of scientific productivity, with a tendency to collective over individual work, mainly in the last decade. Nine co-authoring clusters of greater activity are identified, whose research objects are determined based on three analysis units: scope, content and context. © 2020 CSIC. All Rights Reserved.Las redes de coautoría expresan indirectamente procesos complejos de colaboración científica que trascienden lo institucional y nacional. En el presente estudio se identifican redes de coautoría en el campo de la educación matemática, y se determinan las relaciones estructurales y los campos de investigación en una mayoría visible. Se utilizan métodos bibliométricos con base en 8577 documentos registrados en Scopus (periodo 1969-2018), apoyados en redes de coautoría para identificar los grupos de mayor actividad directa o indirecta. También se utiliza el método Delphi con un panel de 21 expertos a dos rondas, a fin de determinar los respectivos campos de investigación. Se revela un crecimiento acelerado de la productividad científica, con tendencia al trabajo colectivo sobre el individual, principalmente en la última década. Se identifican nueve clústeres de coautoría con mayor actividad, cuyos objetos de investigación se determinan bajo tres unidades de análisis: el ámbito, el contenido y el contexto. © 2020. All Rights Reserved
Gamification strategies for the purpose of improving software processes in project management [Estrategias de gamificación con fines de mejora de procesos software en la gestión de proyectos]
No full textIn the context of Software Engineering, where there are difficulties related to the software project management, gamification is constituted as a support tool for the improvement of its processes. In this way, through gamification strategies, we seek to apply new work approaches that help to solve part of these difficulties. For this reason, this paper presents a study of gamification strategies for improving software project management processes. The strategies have been classified according to the areas of software project management, the expected impact and the gamification elements. © 2019, Associacao Iberica de Sistemas e Tecnologias de Informacao. All rights reserved
Body image (BI) and coping strategies (CS): Analysis of medical and surgical characteristics in women diagnosed with breast cancer [Imagen corporal (IC) y estrategias de afrontamiento (EA): Análisis de las características médico quirúrgicas en mujeres con diagnóstico de cáncer de mama]
No full textFrom a non-experimental transverse design, we sought to identify the possible relationship between BI and CS, and their differences according to surgical-medical variables (surgical intervention, time of diagnosis and stage of cancer). Thirty-seven women diagnosed with breast cancer from all stages participated. The Stress Coping Questionnaire for Oncological Patients (CAEPO), the Body Image Scale (BIS) and an Ad-hoc questionnaire were used. No relationship was found between BI and CS, and these did not vary according to the surgical procedure (radical mastectomy and conservative surgery), the time of diagnosis in years (less than 1, between 1 and 3, between 3 and 5, and more of 5), or the stage (0 or in situ, I, II, III and IV); however, the patients who did not receive surgical intervention showed greater deterioration of their BI than those who did. © 2018 by Sociedad Chilena de Psicología Clínica