Search results for "complex"

Towards human cell simulation

2019

The faithful reproduction and accurate prediction of the phe-notypes and emergent behaviors of complex cellular systems are among the most challenging goals in Systems Biology. Although mathematical models that describe the interactions among all biochemical processes in a cell are theoretically feasible, their simulation is generally hard because of a variety of reasons. For instance, many quantitative data (e.g., kinetic rates) are usually not available, a problem that hinders the execution of simulation algorithms as long as some parameter estimation methods are used. Though, even with a candidate parameterization, the simulation of mechanistic models could be challenging due to the extr…

A Holistic Approach to Comprehending the Complexity of the Post-growth Era: The Emerging Profile

2015

The goal of this study is to investigate the problems caused by the rapid growth of the global economy, coupled with high population growth and the excessive exploitation of natural resources. The global economy will not be able to maintain its current speed of growth in the long term, so a paradigm shift in production and consumption is necessary, if the collapse of ecosystems and the concurrent depletion of natural resources are to be avoided. This is the reason why capitalism needs to take a turn towards a sustainable and naturally harmonized development model.

Reduction in tobacco consumption: an emerging topic within the smoking debate

2009

Alkali consumption of aliphatic carboxylic acids during alkaline pulping of wood and nonwood feedstocks

2013

Abstract The carbohydrate degradation products have been examined, which are formed during the conventional kraft pulping of a softwood, hardwoods, bamboo, and wheat straw as well as soda and soda-anthraquinone pulping of wheat straw. The focus was on “volatile” acids such as formic and acetic acids and “nonvolatile” hydroxy monocarboxylic and dicarboxylic acids. The different consumption profiles were obtained for the charged alkali required for the neutralization of these aliphatic acids depending on the feedstock and the cooking method. The relative composition of the acid fraction in the black liquors of softwood and hardwood and nonwood feedstocks showed characteristic variations. Howe…

Variación espacial de la exposición a contaminación atmosférica en la ciudad de Valencia y su relación con un índice de privación

2013

Objetivo: Evaluar la variación espacial de la exposición a dióxido de nitrógeno (NO2) en la ciudad de Valencia y su relación con la privación socioeconómica y la edad. Métodos: La población por sección censal (SC) procede del Instituto Nacional de Estadística. Los niveles de NO2 se midieron en 100 puntos del área de estudio, mediante captadores pasivos, en tres campañas entre 2002 y 2004. Se utilizó regresión por usos del suelo (LUR) para obtener el mapa de los niveles de NO2. Las predicciones del LUR se compararon con las proporcionadas por: a) el captador más cercano de la red de vigilancia, b) el captador pasivo más cercano, c) el conjunto de captadores en un entorno y d) kriging. Se asi…

Strategic approaches, organizational design and quality management

1998

The main contribution of this paper is to integrate into one model management and organizational fields that are normally analyzed separately: contingency factors, organizational design variables, strategic approaches and quality management approaches. The essential core of the model is constituted by three basic variables of organizational design: level of centralization, level of formalization‐standardization, and level of shared vision and common values. Through analysis using this conceptual tool, we can: assess the position of tasks and organizational units in relation to these organizational variables; evaluate the congruence between organizational variables and contingency factors; i…

Valuing water supply infrastructure improvements using life satisfaction data as a complement to contingent valuation

2019

Uncertainty quantification analysis of the biological Gompertz model subject to random fluctuations in all its parameters

2020

[EN] In spite of its simple formulation via a nonlinear differential equation, the Gompertz model has been widely applied to describe the dynamics of biological and biophysical parts of complex systems (growth of living organisms, number of bacteria, volume of infected cells, etc.). Its parameters or coefficients and the initial condition represent biological quantities (usually, rates and number of individual/particles, respectively) whose nature is random rather than deterministic. In this paper, we present a complete uncertainty quantification analysis of the randomized Gomperz model via the computation of an explicit expression to the first probability density function of its solution s…

An evolutionary method for complex-process optimization

2010

10 páginas, 7 figuras, 7 tablas

Symmetry breaking in a constrained cheeger type isoperimetric inequality

2015

We study the optimal constant in a Sobolev inequality for BV functions with zero mean value and vanishing outside a bounded open set. We are interested in finding the best possible embedding constant in terms of the measure of the domain alone. We set up an optimal shape problem and we completely characterize the behavior of optimal domains.