Sample records for sum rules
from WorldWideScience.org

Sample records 1 - 5 shown.



1

Proposta de método de inspeção de radioproteção aplicada em instalações de medicina nuclear/ Proposal of a radiological protection inspection technique for nuclear medicine facilities

Mendes, Leopoldino da Cruz Gouveia; Fonseca, Léa Mirian Barbosa da; Carvalho, Antonio Carlos Pires
2004-04-01

Resumo em português O objetivo principal deste trabalho é implantar um método de inspeção imparcial e eficiente, visando à utilização segura e correta das radiações ionizantes no campo da medicina nuclear. Este método de inspeção aqui proposto foi aplicado em 113 serviços de medicina nuclear do país, obedecendo a uma freqüência de análise bienal (1996, 1998, 2000 e 2002). Foram estabelecidos 82 itens de radioproteção com pesos para cada item, baseados nos fatores de risco, (mais) de acordo com as normas da Comissão Nacional de Energia Nuclear (CNEN) e as recomendações da Agência Internacional de Energia Atômica. Na análise do serviço, cada item de não conformidade com as normas da CNEN gerou uma irregularidade de radioproteção, com seu peso associado. O somatório dos pesos deu a cada serviço uma pontuação final que o classificou dentro de três faixas de valores que determinaram uma tomada de decisão por parte do órgão regulador e fiscalizador: funcionamento sem restrição - menor que 100 pontos; funcionamento com restrição - igual ou maior que 100 e menor que 300 pontos; funcionamento suspenso - igual ou maior que 300 pontos. Para o caso de irregularidades reincidentes, criou-se um fator multiplicativo para a pontuação. A reincidência em qualquer item de radioproteção (irregularidade) teve seu peso multiplicado por 2n, onde n era o número de vezes em que o item encontrava-se irregular. O estabelecimento prévio de itens de radioproteção, com atribuição de pesos para cada item, procurou minimizar os valores subjetivos e pessoais presentes no julgamento e na avaliação técnica das instituições inspecionadas. Resumo em inglês The main objective of this study is to implement an impartial and efficient inspection method for a correct and secure use of ionizing radiation in nuclear medicine. The radiological protection model was tested in 113 nuclear medicine services (NMS) all over Brazil, following a biannual analysis schedule (1996, 1998, 2000 and 2002). In the analytical process, we adopted the methodology of assigning different importance levels to each of 82 features, based on the risk fact (mais) ors established by the "Comissão Nacional de Energia Nuclear" (CNEN) and on the International Atomic Energy Agency (IAEA) recommendations. A feature was considered a radioprotection fault when in nonconformity with the rules mentioned above, and was imparted a grade. The sum of those grades, classified the NMS in one of the three different ranges, as follows: operating without restriction - 100 points and below; operating with restriction - between 100 and 300 points; temporary shutdown - above 300 points. Permission for the second group to carry on operation should be attached to a defined and restricted period of time (6 to 12 months), considered enough for the NMS to solve the problems and submit to a new evaluation. The NMS's classified in the third group are supposed to go back into operation only after compliance with all the pending radioprotection requirements. Until the next regular evaluation, a multiplication factor 2n was applied to the recalcitrant NMS's, where n is the number of unwilling occurrences. The previous establishment of those items of radioprotection, with their respective grades, excluded subjective and personal values in the judgement and technical evaluation of the institutions.

Scientific Electronic Library Online (Portuguese)

2

Meta-heurística para programação da produção com tempos de preparação dependentes da seqüência/ Metaheuristic for scheduling with dependent setup times

Santos, Hamilton Carlos Massaro; França, Paulo Morelato
1995-12-01

Resumo em português Este trabalho considera o problema de programação da produção, em uma máquina, de um conjunto de ordens de produção que podem ser agrupadas em famílias, sendo que os tempos de preparação entre essas famílias são dependentes da seqüência em que são executadas. Propõe-se um procedimento aproximado, baseado na meta-heurística de Busca Tabu, para a resolução deste problema. A função objetivo considera uma ponderação envolvendo os custos de preparação (mais) de máquina, uma penalidade por atraso em relação à data de entrega das ordens e o custo de estoque. O desempenho do método proposto é avaliado, computacionalmente, frente a três diferentes situações. 1) análise empírica de desempenho da heurística, em função dos parâmetros do problema; 2) comparação entre a heurística e regras de despacho tradicionais EDD e SPT; 3) emprego da heurística para a resolução de um problema prático real. Resumo em inglês This article focuses on the one machine scheduling problem where jobs can be grouped in classes with the same machine setups. The setup times between classes are sequence dependent. An approximation method based on Tabu Search metaheuristic is proposed. The objetive is to minimize the weighted sum of setup costs, tardiness and inventory holding costs. The performance of the heuristic is evaluated through three sets of computational tests: 1) empirical performance analysis (mais) of the heuristic with different data sets; 2) comparison between the heuristic and the well known dispatching rules EDD and SPT; 3) application of the heuristic for solving a real life scheduling problem.

Scientific Electronic Library Online (Portuguese)

3

Influência do cálculo de depreciação no imposto de renda e no fluxo de caixa de uma atividade de transporte florestal/ Influence of methods for calculating depreciation on the income tax and cash flow of a forest transportion activity

Freitas, Luis Carlos de; Silva, Márcio Lopes da; Machado, Carlos Cardoso
2007-04-01

Resumo em português Este trabalho buscou ilustrar um cenário de alternativas na cobrança de impostos, baseado em diferentes métodos de depreciação. A referência foi a atividade de transporte florestal, sendo o estudo desenvolvido para o caminhão bitrem. O fluxo de caixa foi calculado antes e depois dos impostos, sendo estes determinados com base num porcentual incidido sobre a renda tributável, que variou em função das metodologias utilizadas no cálculo da depreciação. Após a e (mais) laboração do fluxo de caixa pós-impostos, realizou-se um estudo econômico utilizando o Valor Presente Líquido (VPL). O impacto do imposto de renda ocasionou retrações na VPL de 53,36%, 52,22%, 50,54%, 48,07% e 47,72% quando se consideraram, respectivamente, os seguintes métodos de depreciação: soma inversa dos dígitos, fundo de renovação, linear, exponencial e soma dos dígitos. A metodologia mais compatível para o bitrem foi a mesma que apresentou maior VPL (soma dos dígitos), indicando que o método adotado pelo governo pode acarretar sobrecarga tributária. Isso reflete a necessidade de se estabelecerem critérios mais justos na cobrança de impostos, através da adoção de metodologias mais adequadas às realidades dos equipamentos. Resumo em inglês This work sought to illustrate a scenario of alternatives to taxation, based on different methods of depreciation. The parameter was the forest transportation activity, being the study developed for the Bitrem truck. Cash flow was calculated before and after taxation, which values were determined on the basis of a percentage on the taxable income, varying according to the methodologies used for calculating depreciation. After drawing up the post-taxation cash flow, an eco (mais) nomic study was carried out using Net Present Value (NPV). The impact of the income tax caused a reduction in NPV of 53.36%, 52.22%, 50.54%, 48.07% and 47.72% respectively when considering the following methods of depreciation: inverse sum of the digits ; sinking fund; linear; exponential and sum of the digits. The most suitable methodology for the forest truck was the same that gave the largest NPV (sum of the digits), indicating that the method adopted by the government can result in tax overload. This shows the need for establishing better taxation rules, using more suitable methods for these types of machines.

Scientific Electronic Library Online (Portuguese)

4

A vegetação no município de Ilhéus Estado da Bahia: IV - Caracaterísticas analíticas e periodicidade sociológica

Veloso, Henrique P.
1947-03-01

Resumo em inglês It is well-known that diverse groups of vegetation with an analogous but not identical floristic composition show an ecological similarity which leads to a determined type of vegetation. Starting from this fact it becomes evident that the scope of phytosociological work is the establishing of the significance of the species within the association and the discovery of the rules which govern associations. The floristic surveys made in the field have to be analysed statistic (mais) ally so as to obtain satisfactory results. The usefulness of this method depends largely on the possibilities of comparing the results with previous studies of the same kind, in the same country, or elsewhere. The method used in this paper is that of measuring circumferences and counting individuals in the different associations studied because it permits the presentation of the results in tables which show the phytosociological complexity of the Brazilian rain-forests. The classical method of characteristics is valuable because the more evolved an association is the less sociable are the species it contains, so that such groups do not show clear differences between species but rather between sinusia or strata of individuals. Five tables are presented in which several of the qualitative and quantitative characteristics are studied with a view to discussing their value in relation to groups and species. They are: I - Abundance (number of individuals). II - Density (distance in meters between the individuals belonging to each stratum). III - Basal coverture (circles measured in square meters of the mean projection of the individuals on the surface). IV - Basal area (mean circle in square meters occupied by individuals on the surface). V - Frequency, abundance and sociability in relation to occurrence. TABLE I. This table indicates first the number of individuals in relation to the sinusia studied: next, the sum total of the individuals belanging to the strata are given for each association, thus providing the numeric value of the sinusia: finally, the relation between the total number of individuals in the association and the total for the sinusium thus fursnishing the abundance per sinusium, in the classic sence, that is the percentage, or rather the relative number, of the elements which compose the group. CONCLUSIONS. The general character of abundance of the regional vegetation of Ilheos may be summed up in the following way: as an association evolves towards permanent equilibirum the number of individuals the inferior strata diminishes in relation to those of the superior strata which increase. For the shrub sinusium, two important facts were observed: a) in a given association the number of elements of the inferior strata diminishes as the diameter of the individuals increases; b) the percentage of individuals belonging to the shrub sinusium in the sere diminishes as the association evolve. In the subarboreal sinusium it is seen that: in the sere the number of subarboreal individuals does not vary much; whereas in the climax or the prisere there is a fall owing to the equilibrum of the biologic forms. In the arboreal sinusium the following conclusion can be deduced from analogous facts: the number of individuals of the lower strata diminishes as circumference increases. Also, in the sere there is a progressive sequence for the individuals belonging to the superior strata. TABLE II. The relation between the mean distances of individuals belonging to the same stratum and the area of an association is equal to the density. The table shows that the mean density of the association and the distance between the individuals belonging to the strata of the same sinusium in relation to the total number of individuals belonging to the association. CONCLUSIONS. As rule, the density of individuals in the associations studied follows a very general character or at least a regional one: the distance between the individuals in the diverse strata varies according to their abundance and sociability. Two other facts of some sociological importance are: a) in identical strata of the same sere the density of individuals oscillates in an analogous manner in teh subclimaces and varies in the stages which have reached equilibrium. b) the density of individuals varias in accordance with the sinusium and the distances between individuals of the same sinusium varg in accordance with the strata. TABLE III. This table presents the mean basal individual coverture, that is the mean projection of the frond of the various individuals belonging to the same stratum. The means were obtained by measurement in the field, of 100 individuals belonging to each stratum and their projection on the surface. In the latoratory these measurements were converted into mean circles (in square meters) and the result was multiplied by the individuals belonging to the strata corresponding to the sinusium of each association. The result obtained is named basal coverture. CONCLUSIONS. As a rule, the basal coverture of the vegetation of the county of Ilhéus indicates that: in the evolution of the vegetation the basal coverture of the arbustive sinusium diminishes progressively whereas that of the arboreal one increases. The special norms obtained are: 1) in the shrub sinusium the basal coverture seems to follow a uniform norm, that is, in stages of evolution of the subclimax the basal coverture oscillates with a certain uniformity. 2) in the subarboreal sinusium this fact is related to the vitality and age of the species, as in the subclimax the number of young trees is large and the vitality of the species very variable. This permits the conclusion that: in the sere the basal coverture increases with the evolution of the vegetation and diminishes when an equilibrium is reached. 3) in the tree sinusium the climax association of the prisere and subsere seem to obey a binomial rule, as the coverture (density-abundance) increases until a determined stratum is reached and...

Scientific Electronic Library Online (Portuguese)

5

A produção da opacidade: estatísticas criminais e segurança pública no Brasil

Lima, Renato Sérgio de
2008-03-01

Resumo em português No Brasil, a análise das estatísticas mostra que dados sobre o crime e a criminalidade existem e fazem parte da história do sistema de justiça criminal do país; no entanto, eles não se transformam, mesmo após a redemocratização, em informações e conhecimento. O aumento da quantidade de dados produzidos, decorrente da modernização tecnológica do Estado, provoca, por sua vez, a opacidade do excesso de exposição e permite que discursos de transparência sejam (mais) assumidos sem, todavia, instaurar mudanças nas regras e práticas de governo. Em suma, a redefinição dos papéis de tais estatísticas e a superação desse quadro têm menos relação com aspectos técnicos, que são controláveis e dependem da tomada de decisões, e, mais, com aspectos políticos que dêem conta de atribuir responsabilidades e resolver conflitos. Resumo em inglês In Brazil, the analysis of statistics shows that crime and criminality data are produced and that they are part of our criminal justice system history. Nevertheless, these data are not transformed into information and knowlegde, even after the re-democratization of the country. The raising amount of produced data, which results from the technological modernization of the state, causes the opacity of excessive exposure and allows the circulation of transparency discourses (mais) without the occurence of actual changes in governmental rules and practices. To sum up, the re-definition of those statistics role does not rely on technical aspects, which are controlable and depend on decision making; it relies on political aspects that can attribute responsibilities and resolve conflicts.

Scientific Electronic Library Online (Portuguese)