Search results for " Flow"
showing 10 items of 3127 documents
Levels and Changes of Physical Activity in Adolescents during the COVID-19 Pandemic: Contextualizing Urban vs. Rural Living Environment
2020
The COVID-19 pandemic and the social distancing implemented shortly after influence physical activity levels (PALs). The purpose of this investigation was to evaluate the changes in PAL and factors associated with PALs among Croatian adolescents while considering the impact of community (urban vs. rural living environment). The sample included 823 adolescents (mean age: 16.5 ±
¿Me voy o me quedo? Factores que influyen en la decisión de abandonar el lugar de nacimiento.
2014
Múltiples factores influyen en la decisión de dispersarse y en cuándo iniciar la dispersión, y su estudio proporciona evidencias de las causas y los determinantes de la dispersión. Los animales abandonan el lugar de nacimiento para dar solución a tres problemas fundamentales: pérdida de calidad del hábitat, competencia por los recursos, y riesgo de consanguinidad. La dispersión, sin embargo, no se lleva a cabo hasta que los individuos alcanzan una condición física adecuada, que permita alcanzar con éxito un nuevo lugar de asentamiento.
Vortex dynamics in rotating counterflow and plane Couette and Poiseuille turbulence in superfluid Helium
2008
An equation previously proposed to describe the evolution of vortex line density in rotating counterflow turbulent tangles in superfluid helium is generalized to incorporate nonvanishing barycentric velocity and velocity gradients. Our generalization is compared with an analogous approach proposed by Lipniacki, and with experimental results by Swanson et al. in rotating counterflow, and it is used to evaluate the vortex density in plane Couette and Poiseuille flows of superfluid helium.
Practical Strategies for Stable Operation of HFF-QCM in Continuous Air Flow
2013
Currently there are a few fields of application using quartz crystal microbalances (QCM). Because of environmental conditions and insufficient resolution of the microbalance, chemical sensing of volatile organic compounds in an open system was as yet not possible. In this study we present strategies on how to use 195 MHz fundamental quartz resonators for a mobile sensor platform to detect airborne analytes. Commonly the use of devices with a resonant frequency of about 10 MHz is standard. By increasing the frequency to 195 MHz the frequency shift increases by a factor of almost 400. Unfortunately, such kinds of quartz crystals tend to exhibit some challenges to obtain a reasonable signal-to…
Performance Dissimilarities in European Union Manufacturing: The Effect of Ownership and Technological Intensity
2021
Our paper addresses the relevance of a set of continuous and categorical variables that describe industry characteristics to differences in performance between foreign versus locally owned companies in industries with dissimilar levels of technological intensity. Including data on manufacturing sector performance from 20 European Union member countries and covering the 2009–2016 period, we used the random forests methodology to identify the best predictors of EU manufacturing industries’ a priori classification based on two main attributes: ownership (foreign versus local) and technological intensity. We found that EU foreign-owned businesses dominate locally owned ones in terms of size, wh…
KOSMOS 2017 Peru Side Experiment: nutrients, phytoplankton abundances, enzyme rates, photophysiology
2022
This data was collected during an short-term incubation experiment in March 2017 that investigated the response of a surface plankton community to upwelling. This experiment was carried in the framework of the SFB754-funded KOSMOS mesocosm study that took place in La Punta, Callao, Peru between February-April 2017. A total of six different treatments were used to disentangle chemical and biological characteristics of deep water that influence surface plankton blooms: 2 different deep water sources with different nutrient concentrations; 3 treatments to distinguish the effects of inorganic nutrients, organic nutrients and deep water microbial populations. Measured variables include inorganic…
RELAP5 simulation of two-phase flow experiments in vertical helical tubes
2010
In the framework of the studies concerning the thermalfluid dynamic phenomena in helicoidal pipes of the innovative nuclear reactor IRIS steam generators, the Department of Nuclear Engineering of the University of Palermo in collaboration with the Politecnico di Torino Department of Energetics has been engaged in a work aimed to adapt, by implementing new suitable models, RELAP5/mod3.2.2β code to simulate the thermalfluid-dynamics and geometries such as the ones involved in helicoidal pipes. In fact this code is based on one-dimensional thermal-hydraulic relationships and presents limitations to model complicated geometry such as helicoidal pipes. Therefore the code was improved with additi…
CO-Evolution Between CCC-Driven Cash Flow Management and Transformation of R&D : Amazon’S Endeavor
2019
Amazon became the world R&D leader in 2017 by rapidly increasing R&D investment. The company’s extremely large amount of R&D funds is the result of an ample free cash flow generated by sophisticated cash conversion cycle (CCC) management. Increased R&D induced business advancement and lean cost structure construction leading to further increase in cash flow which has stimulated interaction between vendors, customers, and Amazon via the Amazon marketplace. Activated interaction accelerated CCC advancement, a subsequent free cash flow increase, and user-driven innovation, thus accelerated the transformation of routine and periodic alteration activities into significant improvement simultaneou…
The variable position of Arctic charr (Salvelinus alpinus (L.)) in subarctic lake food webs
2013
The Circularity of MSW in Urban Landscapes: An Evaluation Method for a Sustainable System Implementation
2022
The debate on the sustainable perspective of a circular economy and MSW (Municipal Solid Waste) management is no longer focused on the resolution of an emergency and on the pure technicality of creating efficient services. New light has been shed on the operational phase, as often unresolvable technical-environmental issues during service management lead to a state of decay, affecting urban vulnerability and users’ involvement. The research aims to develop an auxiliary tool for public administrations in planning a zero-waste future whilst enhancing the urban landscape. This study considers the perspective of virtuous management of the resource flow cycle along with evaluating implementable …