Airflow profile study of a compost dairy barn using a low-cost 3D-printed anemometer network

Mechanical ventilation is commonly used for environmental thermal regulation inside closed-field agricultural production systems. Analyzing the air distribution inside these facilities and the correct operation of the fans can be a challenging. This could be determined using cost prohibitive techniques as particle image velocimetry or deploying large wind sensors networks on-site. To avoid this limitation without a lack of measurement accuracy, this research was focused on developing and test a low-cost anemometer network based in low cost propeller’s anemometers, built using fused 3D-printed and open-hardware platforms. Four propeller anemometers with three to six blades were simulated using the 6-DOF method of ANSYS computer fluid dynamics software. Similar results were obtained for all the simulated models with minor differences. Anemometers were tested in an open circuit wind tunnel before to be evaluated in two open compost dairy barn building using high-volume low-speed and low-volume high-speed fans. Data were analyzed by employing contour maps, descriptive statistics and correlation. The results show that the anemometer network determines the fan’s wind profile for wind speeds over 0.7 m s-1 and it was possible to determine the facilities spots with ventilation problems. The proposed anemometer network and methodology are a good alternative to analyze the operating conditions of the tested agricultural facilities and optimize its performance

Bogomol'nyi Bounds and the Supersymmetric Born-Infeld Theory

We study N=2 supersymmetric Born-Infeld-Higgs theory in 3 dimensions and derive Bogomol'nyi relations in its bosonic sector. A peculiar coupling between the Higgs and the gauge field (with dynamics determined by the Born-Infeld action) is forced by supersymmetry. The resulting equations coincide with those arising in the Maxwell-Higgs model. Concerning Bogomol'nyi bounds for the vortex energy, they are derived from the N=2 supersymmetry algebra.Comment: 24 pages, Latex fil

Spinor techniques for massive fermions with arbitrary polarization

We present a new variant of the spinor techniques for calculating the amplitudes of processes involving massive fermions with arbitrary polarization. It is relatively simple and leads to basic spinor products. Our procedure is not more complex than CALCUL spinor techniques for massless fermions. We obtain spinor Chisholm identities for massive fermions. As an illustration, expressions are given for the amplitudes of electron-positron annihilation into fermions-pairs for several polarizations.Comment: 14 pages, 2 figure

Comparison of airflow homogeneity in Compost Dairy Barns with different ventilation systems using the CFD model

In the pursuit of high milk productivity, producers are using confinement systems in order to improve performance and animal welfare. Among the housing systems, the Compost bedded-pack barns (CBP) stand out. In these barns a bedding area is provided inside, where cows move freely. Generally this area is covered with carbon source material (such as sawdust or fine dry wood shavings) which together with manure, thanks a regular mechanically stirring, ensures the aerobic composting process. The ventilation in these facilities has the function of dehumidifying the air, improving the air quality, drying the bedding, improving the thermal comfort conditions of the confined animals. This work aimed at validating a computational model using Computational Fluid Dynamics (CFD) to determine the best homogeneity of airflows generated by different forced ventilation systems used in CBP barns. Two CBP barns were compared with different ventilation systems: high volume low speed (HVLS) and low volume high-speed (LVHS) fans. The results showed that the proposed model was satisfactory to predict the flows generated by both types of fans. It was concluded that the use of HVLS fans produced a more homogeneous airflow when compared to LVHS fans. The use of mechanical ventilation in tropical conditions is necessary for the proper functioning of the system. In this study, the systems used promoted the increase in air speed to levels close to adequate

Non-Abelian Chern-Simons Vortices

We consider the bosonic sector of a N=2 supersymmetric Chern-Simons-Higgs theory in 2+1 dimensions. The gauge group is U(1)xU(N) and has N_f flavors of fundamental matter fields. The model supports non-Abelian (axially symmetric) vortices when N_f\geq N, which have internal (orientational) moduli. When N_f > N, the solutions acquire additional collective coordinates parameterizing their transverse size. We solve the BPS equations numerically and obtain local (N_f = N) and semi-local (N_f > N) string solutions.Comment: 12 pages, 3 figures. Shortened version, published in Phys. Lett.

El rol de las campañas de comunicación en la promoción de la salud y la prevención de lesiones en salud laboral = The role of the communication campaigns in health promotion and injuries prevention in labour health

Resumen: Introducción: La comunicación juega un papel fundamental en la prevención de accidentes laborales y en la promoción de conductas saludables en el trabajo. Este estudio tiene como objetivo analizar el rol de la comunicación en la salud laboral destacando qué ámbitos han obtenido una mayor aparición en las campañas de comunicación y qué mensajes han tenido una mayor difusión entre la población. Metodología: Este estudio se basa en un diseño de revisión sistemática realizada entre los años 2000 y 2010 en las siguientes bases de datos: ENFISPO, LILACS, Medline, Cuiden Plus y CINAHL. Los descriptores y operadores booleanos en español e inglés fueron: “comunicación” y “condiciones laborales y/o salud laboral”, “communication” and “occupational health and/or working conditions and/or labour conditions”. Los tipos de estudio incluidos fueron experimentales, observacionales, revisiones y opiniones de expertos. Resultados: Catorce estudios reunieron los criterios de inclusión provenientes de las bases de datos españolas y doce estudios provenientes de las internacionales. Las campañas de comunicación realizadas en torno a la salud laboral se centran en ofrecer formación a los profesionales, en prestar atención a sus necesidades, a la cohesión social, motivación, apoyo de los directivos, trabajo en equipo, buena comunicación y recompensas extrínsecas. Otros factores como la edad, situación profesional, centro de trabajo, el sector de actividad, el contacto con el sufrimiento y la muerte, la no realización de actividades de formación, el trabajo por turnos, la violencia, la depresión y el estrés laboral son también temas relevantes en actividades de comunicación en torno a la salud laboral. Conclusiones: Las variables sobre satisfacción laboral son bastante visibles en las campañas. La comunicación en salud laboral va muy unida a la prevención. Los factores que afectan a las condiciones laborales y que pueden generar accidentes de trabajo son frecuentemente difundidos a la población. Algunos estudios señalan una buena comunicación y el apoyo social como la correlación más fuerte en un ambiente de trabajo saludable.Palabras clave: Comunicación, Satisfacción laboral, Salud laboral, Calidad de vida, Lugar de trabajo, Programa de comunicación Abstract: Introduction: Communication plays an important role in the prevention of professional accidents and in the promotion of healthy working environments. This study aims to analyze the role of communication in occupational health highlighting which areas have been reported more population. Methodology: This study is based in a systematic review design done between the years 2000 and 2010 in the following databases: ENFISPO, LILACS, Medline, Cuiden Plus and CINAHL. The keywords were “communication” and “occupational health and/or working conditions and/or labour conditions”. The studies that were included followed these designs: experimental, observational, review and experts’ opinions. Results: Fourteen studies met the inclusion criteria coming from databases from Spain and twelve studies were published in international databases. Communication campaigns which were done around labour health are focused in training to employees, in provide attention to their needs, and to social cohesion, motivation, support to management, team work and good communication. Other factors such as the age, professional situation, working place, activity sector, contact with hard situations and dying, not performing trainings, working in different time frames, violence, depression and the burnout are also relevant areas in communication activities around labour health. Conclusions: Satisfaction at work items are very important in the campaigns. Communication in labour health is very much linked to prevention. Factors that affect to labour conditions and that can generate accidents at work are frequently delivered to the population. Some studies highlight good communication and social support as the hardest correlation in a healthy work environment. Keywords: Communication, Job satisfaction, Occupational health, Quality of life, Workplace, Communication progra

Spinning Pulsating String Solitons in AdS_5 x S^5

We point out the existence of some simple string solitons in AdS_5 x S^5, which at the same time are spinning in AdS_5 and pulsating in S^5, or vice-versa. This introduces an additional arbitrary constant into the scaling relations between energy and spin or R-charge. The arbitrary constant is not an angular momentum, but can be related to the amplitude of the pulsation. We discuss the solutions in detail and consider the scaling relations. Pulsating multi spin or multi R-charge solutions can also be constructed.Comment: 15 pages, Late

Open String Fluctuations in AdS with and without Torsion

The equations of motion and boundary conditions for the fluctuations around a classical open string, in a curved space-time with torsion, are considered in compact and world-sheet covariant form. The rigidly rotating open strings in Anti de Sitter space with and without torsion are investigated in detail. By carefully analyzing the tangential fluctuations at the boundary, we show explicitly that the physical fluctuations (which at the boundary are combinations of normal and tangential fluctuations) are finite, even though the world-sheet is singular there. The divergent 2-curvature thus seems less dangerous than expected, in these cases. The general formalism can be straightforwardly used also to study the (bosonic part of the) fluctuations around the closed strings, recently considered in connection with the AdS/CFT duality, on AdS_5 \times S^5 and AdS_3 \times S^3 \times T^4.Comment: 19 pages, Late

Too dense to go through: the role of low-mass clusters in the pre-processing of satellite galaxies

Galaxie

BPS Equations and the Stress Tensor

We exploit the relationship between the space components of the energy-momentum tensor and the supercurrent to discuss the connection between the BPS equations and the vanishing of the components of the stress tensor in various supersymmetric theories with solitons. Using the fact that certain combination of supercharges annihilate BPS states, we show that $T_{ij}=0$ for kinks, vortices and dyons, displaying the connection between supersymmetry and non-interacting BPS solitons.Comment: 13 pages, LaTe