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A new analytical formulation of retention effects on particle diffusion processes
Bevilacqua, Luiz;Gale?o, Augusto C.N.R.;Costa, Flavio P.;
Anais da Academia Brasileira de Ciências , 2011, DOI: 10.1590/S0001-37652011005000033
Abstract: the ultimate purpose of this paper is to present a new analytical formulation to simulate diffusion with retention in a reactive medium under stable thermodynamic conditions. the analysis of diffusion with retention in a continuum medium is developed after the solution of an equivalent problem using a discrete approach. the new law may be interpreted as the reduction of all diffusion processes with retention to a unifying phenomenon that can adequately simulate the retention effect namely a circulatory motion. it is remarkable that the governing equation requires a fourth order differential term as suggested by the discrete approach. the relative fraction of diffusion particles β is introduced as a control parameter in the diffusion-retention law as suggested by the discrete approach. this control parameter is essential to avoid retention isolated from the diffusion process. two matrices referring to material properties are introduced and related to the real phenomenon through the circulation hypothesis. the governing equation may be highly non-linear even if the material properties are constant, but the retention effect is a function of the concentration level, that is, β is a function of the concentration.
Economic Amplifier - A New Econophysics Model  [PDF]
Ion Spanulescu,Anca Gheorghiu
Quantitative Finance , 2007,
Abstract: Most of the econometric and econophysics models have been borrowed from the statistical physics, and as a cosequence, a new interdisciplinary science called econophysics has emerged. In this paper we planned to extend the analogy between different economic processes or phenomena and processes and phenomena from different fields of physics, other than statistical physics. On the basis of the economic development process and amplification phenomenon analogy, a new econophysics model, named economic amplifier, on the electronic amplification principle from applied physics was proposed und largely analyzed.
The Need of a New Economic Model  [PDF]
Alexandru C?t?lin POPA
Theoretical and Applied Economics , 2012,
Abstract: The current global economic crisis has proven to be unpredictable for most decision-makers worldwide. Moreover, beliefs deeply embedded in the minds of economists about economics, about the virtues of capitalism and free market began to falter. Sooner or later the current crisis will end. The problem that arises and to which the economic science must answer is whether anything should be changed in the current world economic order and especially what exactly. It is quite vital to ask ourselves today in what kind of society we want to live and whether the current economic model, a model mainly based on monetarist ideas, is helping us to achieve those wishes. In addition to analyzing the root causes that led to the current economic crisis, this article aims to analyze whether the current economic model must change and to outline the features of a possible new model.
Development and Nationalism: An Analytical Model on Economic Growth to Social Preference and Party System.
Caroline Law.
Nebula , 2005,
Abstract: The purpose of this paper is to examine the thesis that civic nationalism is more likely to flourish in high-income multi-ethnic countries while ethnic politics is more likely to occur in multi-ethnic countries with low social and economic development. The term “civic nationalism” in this paper is used to denote the phenomenon that a single overarching shared identity exists regardless of the ethnic and other divisions in the society. Although there is an absence of statistical correlation between income and ethnic nationalism, countries with the most successful record of building civic national identity are high-income states. On the other hand, although not all low-income multi-ethnic states resorts to ethnic politics, the most divided ethnic party systems can be found in low-income countries. To explain this phenomenon, one must explore the causes of ethnic nationalist politics.
An Economic Hybrid Analytical Orbit Propagator Program Based on SARIMA Models
Juan Félix San-Juan,Montserrat San-Martín,Iván Pérez
Mathematical Problems in Engineering , 2012, DOI: 10.1155/2012/207381
Abstract: We present a new economic hybrid analytical orbit propagator program based on SARIMA models, which approximates to a 4×4 tesseral analytical theory for a Quasi-Spot satellite. The J2 perturbation is described by a first-order closed-form analytical theory, whereas the effects produced by the higher orders of J2 and the perturbation of the rest of zonal and tesseral harmonic coefficients are modelled by SARIMA models. Time series analysis is a useful statistical prediction tool, which allows building a model for making future predictions based on the study of past observations. The combination of the analytical techniques and time series analysis allows an increase in accuracy without significant loss in efficiency of the new propagators, as a consequence of modelling higher-order terms and other perturbations are not taken into account in the analytical theory.
A New Analytical Radial Distortion Model for Camera Calibration  [PDF]
Lili Ma,YangQuan Chen,Kevin L. Moore
Computer Science , 2003,
Abstract: Common approach to radial distortion is by the means of polynomial approximation, which introduces distortion-specific parameters into the camera model and requires estimation of these distortion parameters. The task of estimating radial distortion is to find a radial distortion model that allows easy undistortion as well as satisfactory accuracy. This paper presents a new radial distortion model with an easy analytical undistortion formula, which also belongs to the polynomial approximation category. Experimental results are presented to show that with this radial distortion model, satisfactory accuracy is achieved.
Constructing economic citizenship: the challenge of a new model of development
T'inkazos , 2005,
Abstract: from the analysis of the bases of economic growth in bolivia in the last fifty years, the author identifies real challenges centered upon the design of creative policies from and for concrete national socio-economic realities and the urgency of micro-economic, industrial policies directed at developing a competitive and diversified economy.
Application of New 3-D Analytical Model for Directional Wellbore Friction  [cached]
Mohammad Fazaelizadeh,Geir Hareland,Bernt Aadnoy
Modern Applied Science , 2010, DOI: 10.5539/mas.v4n2p2
Abstract: Wellbore friction modeling is considered as an important assessment to aid realtime drilling analysis. It predicts and prevents drilling troubles such as tight holes, cutting bed accumulations, differential sticking, etc. This paper presents a new wellbore friction model for drilling horizontal and extended reach wells. This model can be easily applied for all wellbore shapes such as straight, curved and also combination of different curved sections. The model has the capability of torque and drag calculations for different drilling modes such as rotating, tripping and also combination of modes such as reaming and back reaming operations. For improving the model, different effects such as contact surface and hydrodynamic viscous force were included in the model, and their impacts on the results were investigated. To show the application of model, a field case study was used and deviations of modeling results from field data were analyzed precisely.
The Development of a New Analytical Model for the Identification of Saccharide Binders in Paint Samples  [PDF]
Anna Lluveras-Tenorio, Joy Mazurek, Annalaura Restivo, Maria Perla Colombini, Ilaria Bonaduce
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0049383
Abstract: This paper describes a method for reliably identifying saccharide materials in paintings. Since the 3rd millennium B.C., polysaccharide materials such as plant gums, sugar, flour, and honey were used as binding media and sizing agents in paintings, illuminated manuscripts, and polychrome objects. Although it has been reported that plant gums have a stable composition, their identification in paint samples is often doubtful and rarely discussed. Our research was carried out independently at two different laboratories: the Getty Conservation Institute in Los Angeles, USA (GCI) and the Department of Chemistry and Industrial Chemistry of the University of Pisa, Italy (DCCI). It was shown in a previous stage of this research that the two methods give highly comparable data when analysing both reference paint samples and paint layers from art objects, thus the combined data was used to build a large database. In this study, the simultaneous presence of proteinaceous binders and pigments in fresh and artificially aged paint replicas was investigated, and it highlighted how these can affect the sugar profile of arabic, tragacanth, and fruit tree gums. The environmental contamination due to sugars from various plant tissues is also discussed. The results allowed the development of a new model for the reliable identification of saccharide binders in paintings based on the evaluation of markers that are stable to ageing and unaffected by pigments. This new model was applied to the sugar profiles obtained from the analysis of a large number of samples from murals, easel paintings, manuscripts, and polychrome objects from different geographical areas and dating from the 13th century BC to the 20th century AD, thus demonstrating its reliability.
Rethinking the economic costs of malaria at the household level: Evidence from applying a new analytical framework in rural Kenya
Jane M Chuma, Michael Thiede, Catherine S Molyneux
Malaria Journal , 2006, DOI: 10.1186/1475-2875-5-76
Abstract: Cross-sectional surveys in a wet and dry season provide data on treatment-seeking, cost-burdens and coping strategies (n = 294 and n = 285 households respectively). 15 case study households purposively selected from the survey and followed for one year provide in-depth qualitative information on the links between malaria, vulnerability and poverty.Mean direct cost burdens were 7.1% and 5.9% of total household expenditure in the wet and dry seasons respectively. Case study data revealed no clear relationship between cost burdens and vulnerability status at the end of the year. Most important was household vulnerability status at the outset. Households reporting major malaria episodes and other shocks prior to the study descended further into poverty over the year. Wealthier households were better able to cope.The impacts of malaria on household economic status unfold slowly over time. Coping strategies adopted can have negative implications, influencing household ability to withstand malaria and other contingencies in future. To protect the poor and vulnerable, malaria control policies need to be integrated into development and poverty reduction programmes.Malaria is commonly referred to as a disease of poverty and is mainly found in the poorest regions of the world [1,2]. Macro-level studies estimate that the per capita GDP in highly endemic regions is on average one-fifth that of non-endemic countries and that annual growth rates in malaria endemic countries are 1.3 percentage points lower than those of non-endemic countries, even after controlling for other factors known to influence economic growth, such as human capital and initial income [1-3]. Malaria is thought to contribute towards national poverty through its impact on foreign direct investment, tourism, labor productivity and trade. At the micro-level, malaria may cause poverty through spending on health care, income losses and premature deaths. Poor people are considered to be at particular risk of being
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