5,776 research outputs found
Análisis comparativos de métodos de diseño de mezclas de un hormigón de alta resistencia conformado por agregados procedentes de la cantera de Pintag
El siguiente artículo da a conocer el diseño de
mezcla de un hormigón de alta resistencia de 60
MPa conformado por agregados procedentes de
la cantera de Pintag bajo la aplicación de tres
métodos de diseño para su dosificación
(Métodos del ACI, Fuller y Thompson y
Densidad Optima).
La investigación dio inicio con la
caracterización de los agregados, resultados que
fueron utilizados en los diseños para
dosificación de hormigón a partir de diferentes
métodos.
Durante el proceso experimental se realizaron
mezclas de prueba elaboradas a partir de la
adición de agua en la mezcla y a partir de la
incorporación de un aditivo superplastificante,
con el fin de definir la conformación de la
mezcla, para obtener la resistencia y
trabajabilidad requerida.
Por consiguiente, las mezclas definitivas se
definieron mediante la variación de las
proporciones de los materiales (agregado grueso
y agregado fino) conjuntamente con la
incorporación del aditivo superplastificante
Viscomix-Setmix para mejorar las condiciones
de homogeneidad y disminuir la cantidad de
agua en la mezcla.
En cada mezcla se obtuvo muestras
representativas de concreto fresco a las mismas
que se realizaron ensayos de asentamiento,
temperatura, densidad, contenido de aire,
fabricación y curado de especímenes cilíndricos
y, finalmente ensayos de compresión a edades de
1, 3, 7 y 28 días, alcanzando a los 28 días resistencias a la compresión requerida de 72
MPa.The following article reveals the design of a 60
MPa high strength concrete consisting of
aggregates from the Pintag quarry under the
application of different design methods for
dosing (ACI Method, Fuller and Thompson
Method and Optical Density Method).
The investigation began with the
characterization of the aggregates, results that
were used in the designs for concrete dosing
from different methods.
During the experimental process, test mixtures
prepared from the addition of water in the
mixture and from the incorporation of a
superplasticizer additive are mixed, in order to
define the conformation of the mixture and
reducing the water-cement ratio to obtain the
resistance required respectively.
In general, definitive mixtures are defined by
varying the proportions of materials (coarse
aggregate and fine aggregate) with the addition
of Viscomix-Setmix superplasticizer additive to
improve homogeneity conditions and decrease
the amount of water in the mixture.
In each mixture, representative samples of fresh
concrete were obtained, in which settlement,
temperature, density, air content, manufacturing
and curing of cylindrical specimens were
performed, and finally compression tests at ages
1, 3, 7 and 28 days, reaching at 28 days of
required compressive strength of 72MPa
The new rules of global society, flexibility and informality dealing with difficult issues and achieving good results
Economic and social relations, related to the movements of transnational corporations as an important sphere of globalization, have generated a strong impact on the positive law of the states and, as a result, in the international legal system itself. All this has led to studies that point to a new role of the national state, which comes to live with international actors that create rules applied in the internal system of these states. These new rules have proven the inability to discipline and create social relationships, allowing the emergence of private regulatory regimes and a diversity of sources of law describing current legal pluralism. As a private standard of relevant social regulation at a global level, the object of this study is transnational collective bargaining, highlighting its definition, reasoning, legal frameworks, main difficulties of implementation and effectiveness
THE BRAZILIAN CRISIS AND THE STRUCTURAL REFORMS, THE TURN OF THE LABOR REFORM
ABSTRACT The world has changed the practices and laws that govern labor relations. Emerging countries that do not keep up with these changes will not be likely to receive direct foreign investments from foreign investors. Brazil has tried to implement some reforms in the labor area, this is a dilemma that its legislators have to face according to society. Economy and work have always been linked. Since the Industrial Revolution, with the replacement of man by machine, the labor market is undergoing profound changes. The competitiveness in the international market, increasingly fierce, requires countries an attitude change regarding its legislation to adapt to these changes and can develop themselves economically and socially, ensuring quality of life for its citizens. The Brazilian State é neoliberal and, welfare policies need to review its labor laws, created in the era Vargas and fascist bias, extremely patronizing, so that it is an obstacle to the economic development of the country, before the new reality imposed by globalization. KEYWORDS: Human rights; International Labor Law; Foreign Direct Investment; Economic development. RESUMOO mundo mudou as práticas e leis que regem as relações de trabalho. Os países emergentes que não acompanham essas mudanças provavelmente não receberão investimentos estrangeiros diretos de investidores estrangeiros. O Brasil tentou implementar algumas reformas na área do trabalho, este é um dilema que seus legisladores devem enfrentar de acordo com a sociedade. Economia e trabalho sempre foram ligados. Desde a Revolução Industrial, com a substituição do homem pela máquina, o mercado de trabalho está passando por mudanças profundas. A competitividade no mercado internacional, cada vez mais feroz, exige aos países uma mudança de atitude em relação à sua legislação para se adaptar a essas mudanças e se desenvolver economicamente e socialmente, garantindo qualidade de vida para seus cidadãos. O Estado brasileiro é neoliberal e as políticas de bem-estar precisam rever suas leis trabalhistas, criadas na era Vargas e tendência fascista, extremamente condescendentes, de modo que é um obstáculo para o desenvolvimento econômico do país, diante da nova realidade imposta pela globalização.PALAVRAS-CHAVE: Direitos Humanos; Direito Internacional do Trabalho; Investimento Externo Direito; Desenvolvimento Econômico
Radiation induced force between two planar waveguides
We study the electromagnetic force exerted on a pair of parallel slab
waveguides by the light propagating through them. We have calculated the
dependence of the force on the slab separation by means of the Maxwell--Stress
tensor formalism and we have discussed its main features for the different
propagation modes: spatially symmetric (antisymmetric) modes give rise to an
attractive (repulsive) interaction. We have derived the asymptotic behaviors of
the force at small and large separation and we have quantitatively estimated
the mechanical deflection induced on a realistic air-bridge structure.Comment: 10 pages, 6 figure
Reflections on qualitative research in education
ABSTRACT
In this article, we analyze the nature of qualitative research with a particular focuson education, which provides a brief historical background on the evolution of qualitative research and some of the reasons why this approach represents a valid and rigorous methodology to study social phenomena. We analyze the role of the qualitative researcher in terms of the complexity of the observation process, subjectivity, and ethical issues. Qualitative data collection and analysis techniques are discussed in relation to particular approaches to the study of social concerns (e.g. ethnographies, action research), underlining the art of interpretation as a key component of qualitative research and ethical procedures to guarantee the reliability of results.
KEYWORDS: qualitative research; education; reflections; interpretation.
Reflexiones acerca de la investigación cualitativa en educación
RESUMEN
Este artículo analiza la naturaleza de la investigación cualitativa con un enfoque particular en el ámbito educativo. Se proporciona brevemente algunos antecedentes históricos sobre la evolución de la investigación social cualitativa y algunas de las razones por las cuales este enfoque representa una metodología válida y rigurosa para el estudio social. Se analiza el rol del investigador cualitativo desde la complejidad de los procesos de observación, la subjetivad recolección y análisis de datos cualitativo y asuntos éticos. Las técnicas de se discuten considerando enfoques particulares al estudio de los fenómenos sociales (v.g. la etnografía, investigación acción), enfatizando el arte de la interpretación como un componente clave de la investigación cualitativa y los procedimientos éticos para garantizar la validez de los resultados.
PALABRAS CLAVE: Investigación cualitativa; educación; reflexiones; interpretación
A Novel ILP Framework for Summarizing Content with High Lexical Variety
Summarizing content contributed by individuals can be challenging, because
people make different lexical choices even when describing the same events.
However, there remains a significant need to summarize such content. Examples
include the student responses to post-class reflective questions, product
reviews, and news articles published by different news agencies related to the
same events. High lexical diversity of these documents hinders the system's
ability to effectively identify salient content and reduce summary redundancy.
In this paper, we overcome this issue by introducing an integer linear
programming-based summarization framework. It incorporates a low-rank
approximation to the sentence-word co-occurrence matrix to intrinsically group
semantically-similar lexical items. We conduct extensive experiments on
datasets of student responses, product reviews, and news documents. Our
approach compares favorably to a number of extractive baselines as well as a
neural abstractive summarization system. The paper finally sheds light on when
and why the proposed framework is effective at summarizing content with high
lexical variety.Comment: Accepted for publication in the journal of Natural Language
Engineering, 201
System For Open-chest, Multidirectional Electrical Defibrillation
Cardiomyocytes are more sensitive to stimulatory electrical fields when the latter are applied longitudinally to the cell major axis. In the whole heart, cells have different spatial orientations, which may limit the effectiveness of conventional electrical defibrillation (i.e., shock delivery in a single direction). This article describes the constructive aspects of a portable system for rapidly-switching, multidirectional stimulus delivery, composed of an electrical defibrillator and multielectrode-bearing paddles for direct cardiac defibrillation. Methods: The defibrillator delivers monophasic, truncated monoexponential waveforms with energy up to 7.3 J. Upon selection of the defibrillation modality (unidirectional or multidirectional), shock delivery is triggered through 1 or 3 outputs. In the latter case, triggering is sequentially switched to the outputs, without interval or temporal overlap. Each paddle contains 3 electrodes that define shock pathways spaced by 60°. The system was tested in vivo for reversal of experimentally-induced ventricular fibrillation in healthy swine, using 30- and 20-ms long shocks (N= 4 in each group). Results: The defibrillator delivers identical stimulus waveforms through all outputs in both stimulation modalities. In all animals, successful defibrillation required lower shock energy when 20 ms-long stimuli were applied in 3 directions, compared to a single direction. However, performance was poorer with multidirectional defibrillation for 30 ms-long shocks. Conclusion: The delivery of identical shock waveforms allowed confirmation that multidirectional defibrillation can promote restoration of sinus rhythm with lower shock energy, which may reduce myocardial electrical damage during defibrillation. Nevertheless, increase in shock duration greatly impairs the effectiveness of this defibrillation modality.321748
The limitations of the hague convention to solve conflicts arising out of international child kidnapping
Abstract: The present article aims to promote an analysis on the major Conventions concerning the removal and retention of children in different countries than theirs of habitual residence by one of the guardians, in particular the Hague Convention on the Civil Aspects of International Child Abduction, to discuss about the effectiveness on the application of its precepts. The study purposes to identify limitations and omissions in its text susceptible to undermine its applicability in practical cases. Key words: International parental child abduction. Private International Law. Principle of the best interests of the child. Hague Convention. Inter-American Convention
Escala para a medição do risco de infecção associada à assistência à saúde em pacientes adultos: desenvolvimento e validação de conteúdo
Introducción: El ambiente hospitalario envuelve diferentes factores de riesgo relacionados con las infecciones asociadas a la atención sanitaria (IAAS). Un método que contribuye a la prevención y control es la identificación de riesgos que permita la implementación de medidas preventivas. Se cree que dicha identificación se puede llevar a cabo mediante el uso de escalas. El presente estudio intenta desarrollar y validar la validez aparente y el contenido de una nueva escala para medir el riesgo de IAAS en adultos hospitalizados. Materiales y Métodos: Se condujo un estudio metodológico para el desarrollo y la validación aparente y de contenido de la escala de Evaluación de Riesgos de Infección en Pacientes Adultos, la cual se sometió a evaluación por parte de un comité compuesto por 23 expertos con experiencia en IAAS. Se probó la validez de la escala mediante el Índice de Validez de Contenido (IVC). Resultados: Se conservaron 15 ítems de la escala y se agruparon en dos dimensiones: factores intrínsecos y factores extrínsecos. Se necesitaron realizar unos pequeños ajustes para mejorar la claridad de algunos ítems. El IVC de los ítems se ubicó entre 0,83 a 1,0 y el IVC medio de la escala fue de 0,90. Discusión: La escala de Evaluación de Riesgo de Infección en Pacientes Adultos se puede emplear como una tecnología de bajo costo en la medición del riesgo de infección, lo que permite la planeación de intervenciones más precisas y organizadas de parte del equipo de atención médica con el ánimo de prevenir y proveer un cuidado seguro durante la hospitalización. Conclusiones: Los hallazgos soportaron la validación aparente y de contenido de la Escala de Evaluación de iesgo de Infecciones en Pacientes Adultos.
How to cite this article: Rodríguez-Acelas AL, Cañon-Montañez W, Almeida MA. Scale for measurement of healthcare-associated infection risk in adult patients: development and content validation. Rev Cuid. 2019; 10(2): e771. http://dx.doi.org/10.15649/cuidarte.v10i2.771Introduction: Hospital settings involve several risk factors related to healthcare-associated infections (HAIs). A method that contributes to prevention and control is identification of risks to enable implementation of preventative measures. It is believed that this identification can be accomplished using scales. The present study attempts to develop and validate the face and content of a new scale for measuring HAIs risk in hospitalized adults. Materials and Methods: A methodological study conducted to develop and validate the face and content of the Adult Inpatients Infection Risk Assessment scale, which underwent evaluation by a committee of 23 experts with experience in HAIs. The scale’s validity was tested using the Content Validity Index (CVI). Results: 15 items were retained in the scale, grouped into two dimensions: intrinsic and extrinsic factors. Certain minor adjustments were needed to improve the clarity of some items. Items’ CVIs ranged from 0.83 to 1.0 and the scale’s mean CVI was 0.90. Discussion: The Adult Inpatients Infection Risk Assessment scale can be used as a technology of low cost for the measurement of the risk of infection, which allows the planning of more accurate and organized interventions of the health team targeting at preventive and safe care during hospitalization. Conclusions: The findings supported the face and content validity of the Adult Inpatients Infection Risk Assessment Scale.
How to cite this article: Rodríguez-Acelas AL, Cañon-Montañez W, Almeida MA. Scale for measurement of healthcare-associated infection risk in adult patients: development and content validation. Rev Cuid. 2019; 10(2): e771. http://dx.doi.org/10.15649/cuidarte.v10i2.771Introdução: O ambiente hospitalar abrange diferentes fatores de risco relacionados com as infecções associadas ao atendimento sanitário (IAAS). Um método que contribui com a prevenção e o controle é uma identificação de riscos que permita a implantação de medidas preventivas. Considera-se que essa identificação pode ser realizada mediante o uso de escalas. O presente estudo pretende desenvolver e comprovar a validez aparente, bem como o conteúdo de uma nova escala para medir o risco das IAAS em adultos internados. Materiais e Métodos: Foi realizado um estudo metodológico para o desenvolvimento e a validação aparente e de conteúdo da escala de Avaliação de Riscos de Infecção em Pacientes Adultos, que foi analisada por um comitê constituído por 23 especialistas com experiência em IAAS. A validez da escala foi provada mediante o Índice de Validez de Conteúdo (IVC). Resultados: Foram mantidos 15 itens da escala e agrupados em duas dimensões: fatores intrínsecos e fatores extrínsecos. Foi necessário fazer alguns pequenos ajustes para melhorar a clareza de alguns dos itens. O IVC dos itens foi de 0,83 a 1,0 e o IVC médio da escala foi de 0,90. Discussão: A escala de Avaliação de Risco de Infecção em Pacientes Adultos pode ser utilizada como uma tecnologia de baixo custo para a medição do risco de infecção, permitindo o planejamento de cirurgias mais precisas e organizadas por parte da equipe de atendimento médico, com o intuito de prevenir e oferecer um cuidado seguro durante a internação. Conclusões: Os resultados obtidos demonstram a importância da validação aparente e de conteúdo da Escala de Avaliação de Risco de Infecções em Pacientes Adultos.
How to cite this article: Rodríguez-Acelas AL, Cañon-Montañez W, Almeida MA. Scale for measurement of healthcare-associated infection risk in adult patients: development and content validation. Rev Cuid. 2019; 10(2): e771. http://dx.doi.org/10.15649/cuidarte.v10i2.77
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