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This research work aims to analyze the nominal convergence of budgetary variables resulting from the respect of the convergence criteria and the impact of convergence indicators on the exchange rate volatility inner the WAEMU members States. From that end we have conducted the empirical analysis of budgetary convergence in the WAEMU zone by using variables such are: expenditure, incomes and budgetary balances. In order to reach our goal, we have adopted the methodology used by Barro et Salai-Martin (1992) which methodology is implemented by the European Union through the work of Villien et al. (2003). This methodology is consisted of following in the course of the timing an indicator of variable dispersion which may stand as a typical margin or the variance. The results show a global trend to budgetary variables convergence. And then, we have assessed the different indicators of sigma convergence on the profitable exchange rates differential in the WAEMU zone. The model used has revealed the existence of a mechanism of correcting error between the desired exchange rate observed in the zone.
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ABSTRACT: The objective of this research was to forecast the Brazilian national production of agricultural and road machinery in the short term by BOX & JENKINS methodology and determine the persistence effect. Data were obtained at National Association of Automotive Vehicle Manufacturers (ANFAVEA) from January 1960 to October 2019, totaling 718 monthly observations. The Autoregressive Integrated Moving Average (ARIMA) and Autoregressive Conditional Heteroscedasticity (ARCH) methodology were used. The ARIMA (2,1,1)-ARCH (2) model was fitted and persistence of 0.60 was determined, showing that the instability in the series will be for a long period of time.
RESUMO: O objetivo desta pesquisa é prever a produção nacional de máquinas agrícolas e rodoviárias no Brasil, no curto prazo por meio da metodologia BOX & JENKINS e determinar o efeito de persistência na série. Os dados foram obtidos no site da Associação Nacional dos Fabricantes de Veículos Automotores (ANFAVEA) no período de janeiro de 1960 a outubro de 2019, totalizando 718 observações mensais. Os modelos Autoregressivos Integrados e de Médias Móveis (ARIMA) e de Heteroscedasticidade Condicional Autoregressiva (ARCH) foram utilizados para ajustar a média e a variabilidade da série. O modelo ARIMA(2,1,1) - ARCH(2) foi selecionado por meio das estatísticas de ajustes e a persistência determinada foi de 0,60 mostrando que a instabilidade na série é duradoura.
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RESUMO: Este artigo tem dois objetivos principais: mensurar a volatilidade dos resultados das avaliações de Língua Portuguesa e Matemática nas escolas públicas mineiras; e estimar o possível impacto dessas flutuações nos resultados do cumprimento das metas do Ideb. Para tal, analisa-se um banco com dados provenientes da Prova Brasil e do Sistema Mineiro de Avaliação da Educação Básica (Simave). O método estatístico empregado é um modelo longitudinal linear hierárquico que tem a escola como nível de interesse. Entre as principais conclusões obtidas estão: o fato de que as flutuações das notas médias das escolas são bastante acentuadas, mesmo quando se leva em conta a sua tendência de crescimento; e a constatação de que o impacto sobre o cumprimento das metas do Ideb, devido a tais flutuações, pode ser considerável, a ponto de facilitar ou dificultar o sucesso das escolas quanto ao seu cumprimento.
ABSTRACT: This paper has two main purposes. The first one is to obtain a volatility measure of Portuguese and Mathematics mean scores in Minas Gerais State public schools. The second one is to estimate the probable impact of these fluctuations on results of respective Ideb goals. The analysis is based on data obtained from Prova Brasil and Simave (Sistema Mineiro de Avaliação da Educação Básica) tests. The used statistical technique is a longitudinal hierarchical model with the schools as the level of interest. One of the main conclusions obtained is the fact that fluctuation in school mean scores is considerable, even when one takes into account its growth rates. Another relevant conclusion is the fact that this fluctuation can have a considerable impact on the success or failure of a given school in reaching its respective Ideb goals.
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The hollow mesoporous silica nanoparticles (HMSNs) were prepared by hard template method, with a size of 300 nm and shell thickness of 25 nm. Borneol was loaded with solvent impregnation method in order to solve the stability problem of borneol in pharmaceutics, and the BET, TEM and FT-IR were used to characterize the HMSNs and the borneol-HMSNs drug delivery system. The optimal drug loading time, maximum drug loading capacity and the volatility of borneol were investigated. The results showed that HMSNs which were prepared at room temperature and neutral conditions had good sphericity, achieved high drug loading of borneol in a short time, and the drug loading was up to 74.04% within 6 hours; meanwhile, volatility of borneol in the system was greatly improved. This novel drug delivery system provides a new idea for wide application of borneol in the traditional Chinese medicine.
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Volatility can influence the lifetime of particles in the atmosphere, and provide useful information on the formation of secondary aerosol. The previous studies generally utilized thermodenuder ( TD ) to investigate the volatility behavior of particles. Using TD, semivolatile species are vaporized at different temperature, and the vaporized gas is adsorpted by activated charcoal. However, carbon might be emitted from activated charcoal under high temperature or activated charcoal ageing. In this study, a new method was developed for the measurement of particle volatility by coupling a thermodiluter system to an online single particle aerosol mass spectrometer ( SPAMS) . Aerosol particles were passed into two different channels, and then analyzed by SPAMS. Through Channel 1, aerosol particles were heated to different temperature by heating tube, then non-volatile particles and volatile gas entered into the diluter. After diluting and cooling by diluent air, the non-volatile particles were analyzed by SPAMS. Through Channel 2, aerosol particles were analyzed directly by SPAMS without the heating process. Particle volatility was obtained by comparing the information ( particle size, particle number and mass spectrum ) of particles through Channels 1 and 2. Laboratory tests showed that the diluter could avoid the re-condensation of volatiles to the particles. This developed method was applied in the real time measurement of individual particle volatility in the spring of Guangzhou. The results showed that these particles were primarily comprised of highly volatile and moderate volatile species.
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Propósito: Estimar el volumen de humor acuoso como índice de viabilidad ocular. Métodos: El método de cálculo integral de sólidos en revolución por discos, es el utilizado para calcular el volumen del humor acuoso con forma de menisco depositado debajo del aceite de silicona gracias al efecto de la gravedad, y basando dichos cálculos en la mediciones biométricas de diferentes cortes ecográficos, que abarquen tanto el aceite de silicona como el humor acuoso, mediante ecografía ocular. Resultados: De tres modelos matemáticos realizados para el cálculo del volumen del menisco, uno de ellos es el que más se acerca a los valores empíricos, mostrando menor volatilidad en los resultados.
Purpose: To estimate the volume of aqueous humor as an ocular viability index. Methods: The integral calculus of solids in revolution by disks is the method used to calculate the volume of aqueous shaped meniscus deposited under the silicone oil through the effect of gravity, and basing such calculations on biometric measurements of different ultrasound sections, covering both silicone oil as the aqueous humor, by using ocular ultrasound. Results: From the three mathematical models made for calculating the volume of the meniscus, one of them is the closest to the empirical values, showing less volatility in results.
Subject(s)
Ultrasonography , Silicone Oils , Aqueous HumorABSTRACT
Na área das finanças, modelos como o ARCH (autoregressive conditional heteroscedaticity), GARCH (general autoregressive conditional heteroscedasticity) e o modelo de volatilidade estocástica (MVE) são amplamente utilizados na análise de séries de tempo. Por outro lado, essas ferramentas são pouco difundidas na área da saúde. No presente estudo, buscamos transportar os conceitos do MVE para a análise dos registros de doações de sangue do Hemocentro de Ribeirão Preto, São Paulo, realizadas no período de julho de 1996 a junho de 2005. Para isso, utilizamos uma modelagem bayesiana baseada em métodos Monte Carlo em cadeia de Markov. Esse modelo é capaz de apontar os períodos de maior alteração do fluxo de doadores de sangue captados na rotina mensal do Hemocentro ao longo dos anos, e os seus resultados são de grande utilidade para o planejamento de campanhas de doação e captação de doadores, quando identificados os períodos mais críticos para os estoques de bolsas de sangue. O MVE evidencia que, nos anos que compõem o período estudado, o número de doações é caracterizado por uma grande diminuição no número de doações em dezembro, um aumento posterior no mês de janeiro e novamente uma queda em fevereiro.
In studies from the financial literature, models as ARCH (autoregressive conditional heteroscedaticity), GARCH (general autoregressive conditional heteroscedasticity) and the volatility stochastic model are extensively used in the analysis of time series. However, the application of these tools in the health is inexpressive. In the present study, we aimed to adapt the concepts from the volatility stochastic model to the analysis of the records of blood donors who attend Ribeirão Preto Blood Center, São Paulo, Brazil, between July 1996 and June 2005. For this purpose, we used a Bayesian approach based in Markov chain Monte Carlo (MCMC) methods. This model can identify the periods of time when the flux of blood donations collected in the mensal routine of the Blood Center is subject to the largest variation over the years, and its results are very useful for the planning of donation campaigns and search for blood donors, when the most critical periods of blood supply are identified. The volatility stochastic model shows that in the studied period, there is a large decrease in the number of blood donations in December, a subsequent increase in January, and a new decrease in February.
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Objective To study the optimum conditions of extraction and ? - cyclodextrin inclusion for the volatile oil from Radix Angelicae Sinensis, Rhizoma Chuanxiong and Cortex Cinnamomi in Shaofu Zhuyu Tablets. Methods The extraction conditions were evaluated by the ultimate oil extract ratio with single- factor analysis, and the inclusion technology were optimized by the inclusion output ratio and oil- bearing ratio in the inclusion with orthogonal test. Results The optimum conditions for extraction were as follows: smashing the medicinal material into coarse powder (through 10- mesh screen), adding 8 times of the water (mwater ∶ mpander=8 ∶ 1), extracting oil for 4 hours. The best conditions for inclusion were as: the ratio of Oil and ? - cyclodextrin being 1 mL ∶ 8g, and stirring for 2 hours at 50 ℃ . Conclusion The extraction and inclusion conditions in this study are optimal with high oil extract rate, reasonable inclusion process, and minimum cost.
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The effect of wastewater and substance of volatility sewage treatment plant on biological organism is introuduced in this Paper.The results showed that 48h LC50 values of Daphnia and fish are 9.4~57.3% & 4-31% respectively.The mutagenic effect of wastewater was obtained by Ames test.The negative result was obtained.The me-le Wistar rats(body weight 120~150g)were used in the test ground.The rats were divided into expose and control grouPs,the time limit of experiment is for 28 weeks.The result displayed evidently decrease the number of PM(P