Heat Generation in the Railroad Bearing Thermoplastic Elastomer Suspension Element

The main purpose of this ongoing study is to investigate the effect of heat generation within a railroad thermoplastic elastomer suspension element on the thermal behavior of the railroad bearing assembly. Specifically, the purpose of this project is to quantify the heat generated by cyclic loading of the elastomer suspension element as a function of load amplitude, loading frequency, and operating temperature. The contribution of the elastomer pad to the system energy balance is modeled using data from dynamic mechanical analysis (DMA) of the specific materials in use for that part. DMA is a technique that is commonly used to characterize material properties as a function of temperature, time, frequency, stress, atmosphere or a combination of these parameters. DMA tests were run on samples of pad material prepared by three different processes: injection molded coupons, transfer molded coupons, and parts machined from an actual pad. The results provided a full characterization of the elastic deformation (Energy Storage) and viscous dissipation (Energy Dissipation) behavior of the material as a function of loading frequency, and temperature. These results show that the commonly used thermoplastic elastomer does generate heat under cyclic loading, though the frequency which produces peak heat output is outside the range of common loading frequency in rail service. These results can be combined with a stress analysis and service load measurements to estimate internally generated heat and, thus, enable a refined model for the evolution of bearing temperature during operation

Response surface optimization in growth curves through multivariate analysis

A methodology is proposed to jointly model treatments with quantitativelevels measured throughout time by combining the response surface andgrowth curve techniques. The model parameters, which measure the effectthroughout time of the factors related to the second-order response surfacemodel, are estimated. These estimates are made through a suitable transformationthat allows to express the model as a classic MANOVA model,so the traditional hypotheses are formulated and tested. In addition, theoptimality conditions throughout time are established as a set of specificcombination factors by the fitted model. As a final step, two applicationsare analyzed using our proposed model: the first was previously analyzedwith growth curves in another paper, and the second involves two factorsthat are optimized over time

Robust determination of the Higgs couplings: Power to the data

We study the indirect effects of new physics on the phenomenology of the recently discovered "Higgs-like" particle. In a model-independent framework these effects can be parametrized in terms of an effective Lagrangian at the electroweak scale. In a theory in which the S U ( 2 ) L × U ( 1 ) Y gauge symmetry is linearly realized they appear at lowest order as dimension-six operators, containing all the standard model fields including the light scalar doublet, with unknown coefficients. We discuss the choice of operator basis which allows us to make better use of all the available data to determine the coefficients of the new operators. We illustrate our present knowledge of those by performing a global five-parameter fit to the existing data which allows simultaneous determination of the Higgs couplings to gluons, electroweak gauge bosons, bottom quarks, and tau leptons. We find that for all scenarios considered the standard model predictions for each individual Higgs coupling and observable are within the corresponding 90% C.L. allowed range, the only exception being the Higgs branching ratio into two photons for the scenario with standard couplings of the Higgs to fermions. We finish by commenting on the implications of the results for unitarity of processes at higher energies

Constraining anomalous Higgs boson interactions

The recently announced Higgs boson discovery marks the dawn of the direct probing of the electroweak symmetry breaking sector. Sorting out the dynamics responsible for electroweak symmetry breaking now requires probing the Higgs boson interactions and searching for additional states connected to this sector. In this work, we analyze the constraints on Higgs boson couplings to the standard model gauge bosons using the available data from Tevatron and LHC. We work in a model-independent framework expressing the departure of the Higgs boson couplings to gauge bosons by dimension-six operators. This allows for independent modifications of its couplings to gluons, photons, and weak gauge bosons while still preserving the Standard Model (SM) gauge invariance. Our results indicate that best overall agreement with data is obtained if the cross section of Higgs boson production via gluon fusion is suppressed with respect to its SM value and the Higgs boson branching ratio into two photons is enhanced, while keeping the production and decays associated to couplings to weak gauge bosons close to their SM prediction

Determining Triple Gauge Boson Couplings from Higgs Data

In the framework of effective Lagrangians with the S U ( 2 ) L × U ( 1 ) Y symmetry linearly realized, modifications of the couplings of the Higgs field to the electroweak gauge bosons are related to anomalous triple gauge couplings (TGCs). Here, we show that the analysis of the latest Higgs boson production data at the LHC and Tevatron give rise to strong bounds on TGCs that are complementary to those from direct TGC analysis. We present the constraints on TGCs obtained by combining all available data on direct TGC studies and on Higgs production analysis

Relaciones entre peso, condición corporal y producción de leche en vacas del sistema doble propósito

Objetivo. Evaluar las relaciones entre peso corporal, condición corporal y producción de leche en respuesta a la suplementación con semilla de algodón. Materiales y métodos. Se utilizaron 13 vacas y se conformaron dos grupos de tratamientos utilizando un diseño al azar: G1 (n=7) vacas suplementadas con 2 kg. de semilla de algodón; G2 (n=6) vacas no suplementadas. Para el análisis de resultados se emplearon correlaciones de Spearman. Resultados. Se presentaron correlaciones positivas entre la variación de peso corporal y condición corporal (p0.05) en las vacas suplementadas; por el contrario se presentaron correlaciones positivas (p0.05). Conclusiones. La suplementación con semilla de algodón presentó relaciones positivas importantes entre la variación del peso, condición corporal y producción de leche en vacas de primer parto manejadas bajo condiciones de pastoreo

The gauge-Higgs legacy of the LHC Run I

The effective Lagrangian expansion provides a framework to study effects of new physics at the electroweak scale. To make full use of LHC data in constraining higher-dimensional operators we need to include both the Higgs and the electroweak gauge sector in our study. We first present an analysis of the relevant di-boson production LHC results to update constraints on triple gauge boson couplings. Our bounds are several times stronger than those obtained from LEP data. Next, we show how in combination with Higgs measurements the triple gauge vertices lead to a significant improvement in the entire set of operators, including operators describing Higgs couplings

Evento de depredación de Venado Soche (Mazama rufina, Pucheran, 1851) por Taira (Eira barbara Linnaeus, 1758) en el Parque Nacional Natural Chingaza, Colombia

The Tayra (Eira barbara) is one of the least studied carnivores and very little is known about its natural history. The species has omnivorous diet, and is an opportunistic hunter, especially of rodents and the offspring of some arboreal species such as monkeys or sloths. In this note we report the description of a predation event done by a Tayra to a Red Brocket deer (Mazama rufina), recorded on video in the Chingaza National Natural Park, Colombia.La Taira (Eira barbara) es uno de los carnívoros menos estudiados y poco se conoce acerca de su historia natural. La especie posee hábitos alimentarios omnívoros y se caracteriza por ser cazadora oportunista sobre todo de roedores y crías de monos o perezosos. En esta nota reportamos la descripción de un evento de depredación por parte de una Taira a un Venado Soche (Mazama rufina), capturado mediante un video en el Parque Nacional Natural Chingaza, Colombia

Solid waste management applying value stream mapping. a small and medium sized enterprise case

Lean Management es un enfoque que puede ser usado para mejorar el desempeño medioambiental de las pequeñas y medianas empresas (PYMEs), identificar la fuente de residuos sólidos (RS) y proponer estrategias para reducirlos y eliminarlos. En este estudio se propone un enfoque metodológico basado en la aplicación del Mapa de la Cadena de Valor (VSM, Value Stream Mapping) y en la revisión bibliográfica sobre la Gestión de Residuos Sólidos (GRS) incluyendo la construcción del mapa de la situación actual, análisis y la construcción del mapa de la situación deseada, con el fin de identificar e implementar acciones de mejora para GRS en una unidad piloto del sector plástico en Colombia. Los resultados confirman algunas ventajas de la metodología propuesta del VSM como una herramienta práctica de rediseño de flujos de residuos y material en la cadena de valor