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Search Results: 1 - 10 of 51270 matches for " Carlos "
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Theoretical Considerations about the Steady State Combustion of Wood Char in a Bubbling Fluidized Bed Reactor  [PDF]
Carlos Pinho
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.53021
Abstract:

A theoretical study on the performance of steady state bubbling fluidized bed burners is presented using a simple mathematical model. The proposed model has pedagogical and practical advantages due to its simplicity. The calculations, whose results are plotted in several graphics, were based on data obtained in laboratory scale experiments. The experiments were carried out with wood chars and the model allows a proper evaluation of physical and chemical phenomena taking place inside the reactor, as well as a fast approach to the pre-design phase, before going towards more complex and time consuming numerical modeling. In the first part of the paper the steady state modeling is compared with the combustion of successive batches of char particles. Afterwards, the performance of a 1 m diameter bed operating from 700 to 800 is shown.

Volume of Geodesic Balls in Finsler Manifolds of Hyperbolic Type  [PDF]
Carlos Ogouyandjou
Advances in Pure Mathematics (APM) , 2014, DOI: 10.4236/apm.2014.48050
Abstract:

Let  be a compact Finsler manifold of hyperbolic type, and \"\" be its universal Finslerian covering. In this paper we show that the growth function of the volume of geodesic balls of \"\" is of purely exponential type.

Generalized Uncertainty Relations, Curved Phase-Spaces and Quantum Gravity  [PDF]
Carlos Castro
Journal of Applied Mathematics and Physics (JAMP) , 2016, DOI: 10.4236/jamp.2016.410189
Abstract: Modifications of the Weyl-Heisenberg algebra \"\" are proposed where the classical limit \"\" corresponds to a metric in (curved) momentum spaces. In the simplest scenario, the 2D de Sitter metric of constant curvature in momentum space furnishes a hierarchy of modified uncertainty relations leading to a minimum value for the position uncertainty . The first uncertainty relation of this hierarchy has the same functional form as the stringy modified uncertainty relation with a Planck scale minimum value for \"\" at \"\" . We proceed with a discussion of the most general curved phase space scenario (cotangent bundle of spacetime) and provide the noncommuting phase space coordinates algebra in terms of the symmetric \"\" and nonsymmetric \"\" metric components of a Hermitian complex metric \"\" , such \"\" . Yang’s noncommuting phase-space coordinates algebra, combined with the Schrodinger-Robertson inequalities involving angular momentum eigenstates, reveals how a quantized area operator in units of \"\" emerges like it occurs in Loop Quantum Gravity (LQG). Some final comments are made about Fedosov deformation quantization, Noncommutative and Nonassociative gravity.
Higher-Order Corrections for the Deflection of Light around a Massive Object. Diagonal Padé Approximants and Ray-Tracing Algorithms  [PDF]
Carlos Rodriguez, Carlos Marín
International Journal of Astronomy and Astrophysics (IJAA) , 2018, DOI: 10.4236/ijaa.2018.81009
Abstract: From the Schwarzschild metric we obtain the higher-order terms for the deflection of light around a massive object using the Lindstedt-Poincaré method to solve the equation of motion of a photon around the stellar object. The asymptotic series obtained by this method was obtained up to order 20 in the expansion parameter, and was found to better approximate the numerical solution with higher order terms—a property that can’t be taken for granted for any asymptotic series. Additionally, we obtain diagonal Padé approximants from the perturbation expansion, and we show how these are a better fit for the numerical data than the original formal Taylor series. Furthermore, we use these approximants in ray-tracing algorithms to model the bending of light around massive objects.
Implementing Good Governance Principles for the Public Sector in Information Technology Governance Frameworks  [PDF]
Carlos Juiz, Carlos Guerrero, Isaac Lera
Open Journal of Accounting (OJAcct) , 2014, DOI: 10.4236/ojacct.2014.31003
Abstract: In this paper, we are showing how Information Technology (IT) governance frameworks contribute to the implementation of the key principles of the good corporate governance, particularly, in the public sector. We demonstrate that there are numerous links, explicitly and implicitly expressed through a set of IT governance instruments, matching the proposals of good governance principles with the behavioral goals of an IT governance framework implementation. We also provide a real experience of using a set of possible instruments, in our public university, through an IT governance framework based on the ISO/IEC 38500 standard. We also present the maturity of the good governance principles implementation with this set of instruments, after governing IT in our university during the period 2007-2013. We show that using an IT governance framework in a public entity mutually reinforces the key principles of good governance, especially the transparency and accountability goals for the IT assets.
Comments on the Article “Improved Hemodynamics with the Use of Prophylactic Infusion of Epinephrine and or Norepinephrine during Transcatheter Aortic Valve Replacement (TAVR)”  [PDF]
Carlos Galhardo Jr., Carlos Darcy Alves Bersot
Open Journal of Anesthesiology (OJAnes) , 2015, DOI: 10.4236/ojanes.2015.510039
Abstract: Transcatheter aortic valve replacement (TAVR) is a new therapeutic option to treat patients with symptomatic severe aortic stenosis, and a prohibitive mortality risk for conventional surgical AVR2. A thorough understanding of the procedural steps involved in TAVR is imperative for all components of the heart time. Balloon aortic valvuloplasty under rapid ventricular pacing is one of the main procedural steps, and is usually performed before valve insertion to enable passage of the prosthesis through the stenotic native aortic valve. Hemodynamic collapse necessitating prompt intervention may occur at different stages during the procedure.
Freedom of Conscience is Freedom of Choice: Women’s Reproductive Needs, Rights, and their Therapeutic Implications  [PDF]
Carlos M. Del Rio
Advances in Applied Sociology (AASoci) , 2012, DOI: 10.4236/aasoci.2012.23028
Abstract: Using reasonableness, we examine the U.S. Catholic bishops’ opposition to provisions of the Affordable Care Act of 2010. Weaving contributions from theology, philosophy, and jurisprudence, we emphasize the reasonable importance of mental health therapy for women within a relevant Catholic/Christian dialogue, particularly in the wake of the U.S. Supreme Court’s decision on healthcare. We principally identify socially imbedded factors that contribute to ending unwanted pregnancies, and argue that freedom of conscience is indeed freedom of choice within which women’s reproductive needs lie under protections of the U.S. Constitution. We recognize that Catholic tradition originates in the words and behaviors of Jesus. Examining closely these actions toward women, we find no reasonable justification for the bishops’ position against women’s freedom of conscience. We also discovered that revelation does not belong exclusively to the bishops; truth continues to be revealed to all human consciences, and true freedom does not allow for coercion/castigation of dogmatic import. We advocate for women’s ability to openly discuss their struggles to meet their reproductive condundra and to deconstruct their sexual stereotypes in mental health therapy. We provide crucial recommendations to augment choices for women’s reproduction condundra, and incite the need for new epistemic frameworks to address the complexity of female sexuality.
Computer Aided Call for Tenders: A Tool for Software Bidding  [PDF]
Jorge Hochstetter, Carlos Cares
Journal of Software Engineering and Applications (JSEA) , 2014, DOI: 10.4236/jsea.2014.77055
Abstract:

Under a broad comprehension of Software Engineering, it is preferred the term software life cycle instead of just software production. The reason is that cycle starts at software conception and stops when the software is relegated. Given contemporary companies’ market strategies of focusing on their competitive advantages, most of them have externalized their software production to outsourced services. Therefore, the call for software tenders has become a common step in the software life cycle. In this paper, we present a tool which aids non-experts to specify call for software tenders. The motivation was Chile situation of most of rural and semi-urban city halls which do not have engineering teams to build call for software tenders. We describe the problem in terms of lack of competitiveness and empty biddings generated by low quality calls for tenders. As a second step, we show the technical considerations to develop the proposed tool and its features. We include an initial tool perception from a first group of users.

Economic Aspects of Omnipotence  [PDF]
Francisco Carlos Ribeiro
Theoretical Economics Letters (TEL) , 2014, DOI: 10.4236/tel.2014.43024
Abstract: This article purposes that omnipotence feelings are the best issue to explain the relationship between ostentation and socio-economic behavior. According to my propositions, we would better comprehend the mechanisms of ostentation in our society, and its consequences not only to the economy, but also to income redistribution initiatives, if we understand the interaction among omnipotence, commodity fetishism concepts and cultural values. The article also purposes in this direction, to measure the commodity fetishism degree as a valuable tool for economics.
Effects of Solar UV Radiation on Materials Used in Agricultural Industry in Salta, Argentina: Study and Characterization  [PDF]
Carlos Cadena, Delicia Acosta
Journal of Materials Science and Chemical Engineering (MSCE) , 2014, DOI: 10.4236/msce.2014.24001
Abstract: The current study presents the characterization of three types of materials after exposure to solar UV radiation. The selection of the materials is related to socio-economic aspects and rural activities in the northwest of Argentina (a.k.a. NOA). The objective was to establish a time parameter that allows estimating the durability of the materials according to their use. One of the materials is used as a protective cover (polyethylene film) of greenhouses, which are used for crop cultivation in the area. Another material is used in photovoltaic modules (PVMs), which are used to supply energy in isolated areas and the third material is sunscreen used by people that are exposed to UV radiation during rural activities. Degradation or deterioration of the materials was monitored using different spectroscopic assays: infrared was used to detect any structural changes in the material, X-rays were used for possible changes in the crystalline structure of the material, and spectral transmittance as this property is likely to be affected by changes in the structure of the material. The results showed that degradation of polyethylene seems to be related to the diminution in transparency and the loss of mechanical resistance with increasing exposure time. The decrease in transparency of one of the layers of a PVM caused a considerable decrease in the energy generated, whereas the sunscreens with a low sun protection factor (SPF) rapidly lost their protective properties and changed their photostability properties. Our results revealed a relationship between relative transmittance loss and exposure timse, which allows estimating the stability of different materials.
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