Identities of Choi-Lee-Srivastava involving the Euler-Mascheroni’s constant

We give an elementary deduction of the Choi-Lee-Srivastava’s identities involving the Euler Mascheroni’s constant, thus from them is immediate the identity of Wilf

The exergy costs of electrical power, cooling, and waste heat from a hybrid system based on a solid oxide fuel cell and an absorption refrigeration system

This paper applies the Exergy Cost Theory (ECT) to a hybrid system based on a 500 kWe solid oxide fuel cell (SOFC) stack and on a vapor-absorption refrigeration (VAR) system. To achieve this, a model comprised of chemical, electrochemical, thermodynamic, and thermoeconomic equations is developed using the software, Engineering Equation Solver (EES). The model is validated against previous works. This approach enables the unit exergy costs (electricity, cooling, and residues) to be computed by a productive structure defined by components, resources, products, and residues. Most importantly, it allows us to know the contribution of the environment and of the residues to the unit exergy cost of the product of the components. Finally, the simulation of different scenarios makes it possible to analyze the impact of stack current density, fuel use, temperature across the stack, and anode gas recirculation on the unit exergy costs of electrical power, cooling, and residues

Study through Geant4, for Time Resolution characterization of different detectors arrays coupled with two SiPMs, as a function of: the scintillator plastic material, its volumetric dimensions and the location of the radiation emission source

The high time resolution detectors are relevant in those experiments or simulations were the particles to detect, have a very short time of flight (TOF), and due this it´s required that the detections times are ranged between ns. & ps.Using Geant4 software, it was made thirty simulations of coupled detectors to plastic scintillators with two silicon photomultipliers (SiPMs) located on the scintillator’s central sides. To characterize the time resolution, it was required to quantify the optical photons that reach the Score in a certain time, which are generated by muons on the surface of the plastic scintillator. Different configurations of muon beams were simulated at energy of 1 GeV, to interact with the configuration of the scintillator material of its corresponding arrangement. The simulations were made varying three parameters: the scintillator material “BC404 & BC422”, its size, and the location of the radiation source. Fifteen simulations correspond to BC404 material & fifteen simulations to BC422 material respectively. The first five simulations consisted in varying the scintillator’s volumetric size and collocate the muons beam guided randomly distributed over it, the next five simulations differentiate from setting up a directly centered beam, and the last five simulations for guide the beam on the left lower corner of each scintillator.The best time resolution achieved was σ= 8.67 +/− 0.26 ps., reported by the detector with BC422 scintillator material which has a volume of 20x20x3 mm3

Fundamental care and knowledge interests: implications for nursing science

Aims and objectives: The aim of this discursive paper was to characterize the intra-theoretical interests of knowledge in nursing science as an epistemological framework for fundamental care. Background: For Jürgen Habermas, theory does not separate knowledge interests from life. All knowledge, understanding and human research is always interested. Habermas formulated the knowledge interests in empirical-analytical, historical hermeneutic and critical social sciences; but said nothing about health sciences and nursing science. Design: Discursive paper. Results: The paper is organised into five sections that develop our argument about the implications of the Habermasian intra theoretical interests in nursing science and fundamental care: the persistence of a technical interest, the predominance of a practical interest, the importance of an emancipatory interest, “being there” to understand individuals’ experience and an “existential crisis” that uncovers the individual’s subjectivity. Conclusions: The nursing discipline can take on practical and emancipatory interests (together with a technical interest) as its fundamental knowledge interests. Nurses’ privileged position in the delivery of fundamental care gives them the opportunity to gain a deep understanding of the patient’s experience and illness process through physical contact and empathic communication. Relevance to clinical practice and nursing research: In clinical, academic and research environments, nurses should highlight the importance of fundamental care, showcasing the value of practical and emancipatory knowledge. This process could help to improve nursing science’s leadership, social visibility and idiosyncrasy

Seguimiento de la productividad en obra: técnicas de medición de rendimientos de mano de obra

Management systems often present few, since those systems don't adopt control indexes like productivity, which prevents form identifying and defining (from both the systematic and systemic point of view) the problems that require taking corrective and mitigating actions [1]. Methodologies such as "Lean Construction" are based on the management of processes, to maximize revenues and minimize costs, here the improvement of productivity becomes an important parameter for the management system; focusing on the verification of both the process and the product, leaving behind the typical tendency of verifying only results, that is the tendency for control techniques [2]. This study pretends to identify the controlling techniques that should be used when referring to productivity as the quality management control index.En todo sistema de gestión, la planeación sirve como marco de referencia a los programas de control. Adoptar buenas metodologías de seguimiento que acompañen a los procesos de planeación, con miras a lograr un buen desempeño en la gestión y alcanzar las metas deseadas, es una necesidad latente. Aunque en las nuevas metodologías de gestión se hace ya explícita esta necesidad, es muy frecuente encontrar dificultades en los procesos de seguimiento de obra, al no emplearse indicadores adecuados que identifiquen, sistemática y sistémicamente, situaciones importantes que requieran corrección y/o mitigación [1]. La mayoría de las metodologías modernas de mejoramiento basan su estrategia buscando maximizar valor y minimizar pérdidas, razón por la cual, la productividad es uno de los indicadores importantes que mide el desempeño de una buena gestión. Este enfoque, es un planteamiento estratégico orientado hacia los procesos, donde prevalece la verificación y el aseguramiento del procedimiento y el resultado, más allá del viejo esquema de solo verificar resultados [2]. El presente trabajo apunta hacia metodologías de seguimiento, que definan a la productividad, como un indicador significativo de gestión y control en las obras de construcción, en especial la productividad de las cuadrillas de trabajo.&nbsp

Seguimiento de la productividad en obra: técnicas de medición de rendimientos de mano de obra

Management systems often present few, since those systems don't adopt control indexes like productivity, which prevents form identifying and defining (from both the systematic and systemic point of view) the problems that require taking corrective and mitigating actions [1]. Methodologies such as "Lean Construction" are based on the management of processes, to maximize revenues and minimize costs, here the improvement of productivity becomes an important parameter for the management system; focusing on the verification of both the process and the product, leaving behind the typical tendency of verifying only results, that is the tendency for control techniques [2]. This study pretends to identify the controlling techniques that should be used when referring to productivity as the quality management control index.En todo sistema de gestión, la planeación sirve como marco de referencia a los programas de control. Adoptar buenas metodologías de seguimiento que acompañen a los procesos de planeación, con miras a lograr un buen desempeño en la gestión y alcanzar las metas deseadas, es una necesidad latente. Aunque en las nuevas metodologías de gestión se hace ya explícita esta necesidad, es muy frecuente encontrar dificultades en los procesos de seguimiento de obra, al no emplearse indicadores adecuados que identifiquen, sistemática y sistémicamente, situaciones importantes que requieran corrección y/o mitigación [1]. La mayoría de las metodologías modernas de mejoramiento basan su estrategia buscando maximizar valor y minimizar pérdidas, razón por la cual, la productividad es uno de los indicadores importantes que mide el desempeño de una buena gestión. Este enfoque, es un planteamiento estratégico orientado hacia los procesos, donde prevalece la verificación y el aseguramiento del procedimiento y el resultado, más allá del viejo esquema de solo verificar resultados [2]. El presente trabajo apunta hacia metodologías de seguimiento, que definan a la productividad, como un indicador significativo de gestión y control en las obras de construcción, en especial la productividad de las cuadrillas de trabajo.&nbsp

Towards an integrated mycorrhizal technology: harnessing mycorrhizae for sustainable intensification in agriculture

Sustainability in Agriculture In order to meet future needs of a growing human population and to achieve food security in the context of climate change, food production will likely need to increase—among other measures—while at the same time minimizing negative environmental impact (Foley et al., 2011). Sustainable intensification of agriculture (Garnett et al., 2013; Pretty and Bharucha, 2014; Andres and Bhullar, 2016; Gunton et al., 2016), sometimes also called ecological intensification, is likely to include key aspects of conservation agriculture (e.g., Hobbs et al., 2008; Giller et al., 2015). Pillars of conservation agriculture (FAO, 2015) are no-till practices (Pittelkow et al., 2015), continuous crop cover (by various means, for example cover crops) and diversification practices (multi-cropping and crop rotations; Ponisio et al., 2015)

Parameters of Herbig Ae/Be and Vega-type stars

This work presents the determination of the effective temperature, gravity, metallicity, mass, luminosity and age of 27 young early-type stars, most of them in the age range 1-10 Myr, and three -suspected- hot companions of post-T Tauri stars belonging to the Lindroos binary sample. Most of these objects show IR excesses in their spectral energy distributions, which are indicative of the presence of disks. The work is relevant in the fields of stellar physics, physics of disks and formation of planetary systems. Spectral energy distributions and mid-resolution spectra were used to estimate the effective temperature. The comparison of the profiles of the Balmer lines with synthetic profiles provides the value of the stellar gravity. High-resolution optical observations and synthetic spectra are used to estimate the metallicity, [M/H]. Once these three parameters are known for each star, evolutionary tracks and isochrones provide estimations of the mass, luminosity, age and distance (or upper limits in some cases). The method is original in the sense that it is distance-independent, i.e. the estimation of the stellar parameters does not require, as it happens in other works, the knowledge of the distance to the object. A detailed discussion on some individual objects, in particular VV Ser, RR Tau, 49 Cet and the three suspected hot companions of post-T Tauris, is presented. The paper also shows the difficulty posed by the morphology and behaviour of the system star+disk in the computation of the stellar parameters.Comment: 18 pages, 11 figure