Development of a spectrophotometric Sequential Injection Analysis (SIA) procedure for determination of ammonium: A Response Surface Methodology (RSM) approach

This paper describes the optimization and use of a Sequential Injection Analysis (SIA) procedure for ammonium determination in waters. Response Surface Methodology (RSM) was used as a tool for optimization of a procedure based on the modified Berthelot reaction. The SIA system was designed to (i) prepare the reaction media by injecting an air-segmented zone containing the reagents in a mixing chamber, (ii) to aspirate the mixture back to the holding coil after homogenization, (iii) drive it to a thermostated reaction coil, where the flow is stopped for a previously established time, and (iv) to pump the mixture toward the detector flow cell for the spectrophotometric measurements. Using a 100 mu mol L(-1) ammonium solution, the following factors were considered for optimization: reaction temperature (25 - 45 degrees C), reaction time (30 - 90 s), hypochlorite concentration (20 - 40 mmol L(-1)) nitroprusside concentration (10 - 40 mmol L(-1)) and salicylate concentration (0.1 - 0.3 mol L(-1)). The proposed system fed the statistical program with absorbance data for fast construction of response surface plots. After optimization of the method, figures of merit were evaluated, as well as the ammonium concentration in some water samples. No evidence of statistical difference was observed in the results obtained by the proposed method in comparison to those obtained by a reference method based on the phenol reaction. (C) 2010 Elsevier B.V. All rights reserved.

Development of an Analytical Methodology for Quantification of Strong Acid in Diesel Oil

Many factors can affect the quality of diesel oil, in particular the degradation processes that are directly related to some organosulfur compounds. During the degradation process, these compounds are oxidized into their corresponding sulfonic acids, generating a strong acid content during the process. p-Toluene sulfonic acid analysis was performed using the linear sweep voltammetry technique with a platinum ultramicroelectrode in aqueous solution containing 3 mol L(-1) potassium chloride. An extraction step was introduced prior to the voltammetric detection in order to avoid the adsorption of organic molecules, which inhibit the electrochemical response. The extraction step promoted the transference of sulfonic acid from the diesel oil to an aqueous phase. The method was accurate and reproducible, with detection and quantification limits of 5 ppm and 15 ppm, respectively. Recovery of sulfonic acid was around 90%.

Design/Evaluation of A Methodology For Performance Optimization Of Indexable Carbide Inserts

In this project, two broad facets in the design of a methodology for performance optimization of indexable carbide inserts were examined. They were physical destructive testing and software simulation.For the physical testing, statistical research techniques were used for the design of the methodology. A five step method which began with Problem definition, through System identification, Statistical model formation, Data collection and Statistical analyses and results was indepthly elaborated upon. Set-up and execution of an experiment with a compression machine together with roadblocks and possible solution to curb road blocks to quality data collection were examined. 2k factorial design was illustrated and recommended for process improvement. Instances of first-order and second-order response surface analyses were encountered. In the case of curvature, test for curvature significance with center point analysis was recommended. Process optimization with method of steepest ascent and central composite design or process robustness studies of response surface analyses were also recommended.For the simulation test, AdvantEdge program was identified as the most used software for tool development. Challenges to the efficient application of this software were identified and possible solutions proposed. In conclusion, software simulation and physical testing were recommended to meet the objective of the project.

Methodology for identifying parameters for the TRNSYS model Type 210 -wood pellet stoves and boilers

This report describes a method how to perform measurements on boilers and stoves and how to identify parameters from the measurements for the boiler/stove-model TRNSYS Type 210. The model can be used for detailed annual system simulations using TRNSYS. Experience from measurements on three different pellet stoves and four boilers were used to develop this methodology. Recommendations for the set up of measurements are given and the re-quired combustion theory for the data evaluation and data preparation are given. The data evalua-tion showed that the uncertainties are quite large for the measured flue gas flow rate and for boilers and stoves with high fraction of energy going to the water jacket also the calculated heat rate to the room may have large uncertainties. A methodology for the parameter identification process and identified parameters for two different stoves and three boilers are given. Finally the identified models are compared with measured data showing that the model generally agreed well with meas-ured data during both stationary and dynamic conditions.

Towards a Methodology for Coordination Mechanism Selection in Open Systems

Agent-oriented software engineering (AOSE) is a promising approach to developing applications for dynamic open systems. If well developed, these applications can be opportunistic, taking advantage of services implemented by other developers at appropriate times. However, methodologies are needed to aid the development of systems that are both flexible enough to be opportunistic and tightly defined by the application requirements. In this paper, we investigate how developers can choose the coordination mechanisms of agents so that the agents will best fulfil application requirements in an open system.

PrIMe: A Methodology for Developing Provenance-Aware Applications

Provenance refers to the past processes that brought about a given (version of an) object, item or entity. By knowing the provenance of data, users can often better understand, trust, reproduce, and validate it. A provenance-aware application has the functionality to answer questions regarding the provenance of the data it produces, by using documentation of past processes. PrIMe is a software engineering technique for adapting application designs to enable them to interact with a provenance middleware layer, thereby making them provenance-aware. In this article, we specify the steps involved in applying PrIMe, analyse its effectiveness, and illustrate its use with two case studies, in bioinformatics and medicine.

Diagnóstico sistêmico de uma farmácia de manipulação de Porto Alegre com a utilização da "Soft Systems Methodology"

As empresas e instituições estão num ambiente que oferece oportunidades e ameaças, o que exige um conjunto de informações voltado tanto a processos e decisões táticas, operacionais e estratégicos. No entanto, conseguir informações com rapidez e qualidade não se trata apenas de adquirir pacotes de sistemas de informações ou mesmo desenvolvê-los nas organizações. Infelizmente, isto é o que mais tem ocorrido. Desta forma, a fim de ultrapassar esse amadorismo, faz-se necessário um diagnóstico sistêmico da organização, com objetivo de identificar os requisitos informacionais necessários à construção de um sistema de apoio às decisões. Destarte, este estudo realiza um diagnóstico sistêmico numa farmácia com a utilização da “Soft Systems Methodology”, a qual a partir de ampla interação entre pesquisador e as pessoas envolvidas , identifica e estrutura a situação problemática de forma encadeada, analisando-a sob duas preocupações: uma relacionada ao mundo real e outra ao pensamento sistêmico. Com este processo, desenvolve uma aprendizagem que permite não só a identificação dos requisitos informacionais necessários à construção de um sistema de informações como também reunir e organizar visões muitas vezes divergentes a respeito de uma realidade complexa, a fim de propor um rol de atividades e ações que possam contribuir para o processo de melhoria da situação problemática.

DSGE model with banking sector for emerging economies : estimated using Bayesian methodology for Brazil

Economias emergentes sofrem importantes restrições de crédito quando comparadas com economias desenvolvidas, entretanto, modelos estocásticos de equilíbrio geral (DSGE) desenhados para economias emergentes ainda precisam avançar nessa discussão. Nós propomos um modelo DSGE que pretende representar uma economia emergente com setor bancário baseado em Gerali et al. (2010). Nossa contribuição é considerar uma parcela da renda esperada como colateral para empréstimos das famílias. Nós estimamos o modelo proposto para o Brasil utilizando estimação Bayesiana e encontramos que economias que sofrem restrição de colateral por parte das famílias tendem a sentir o impacto de choques monetários mais rapidamente devido a exposição do setor bancário a mudanças no salário esperado.

Rumo a um desenho técnico de um sistema de apoio à decisão para uma reconfiguração do soft systems methodology: o caso do planejamento sistêmico

A multidisciplinaridade da tomada de decisão sofre com as peculiaridades de qualquer campo multidisciplinar. A falta de comunicação, muitas vezes, gera problemas e as respostas que podem ser encontradas dentro de outras áreas. Os Métodos de Estruturação de Problemas são respostas para os questionamentos atuais nas escolas de administração e negócios, principalmente o uso multimetodológico destes com outros métodos. Tendo o Soft Systems Metholodogy – SSM – como base, e a incorporação do Strategic Options Development and Analysis – SODA – ao processo do SSM, Georgiou (2012) apresenta o Planejamento Sistêmico em sua configuração mais recente. Visando buscar uma ferramenta computacional que atenda os pressupostos do SSM, e que incorpore as especificações da configuração do Planejamento Sistêmico, definem-se uma notação para o método e uma formalização das para as comunicações existentes entre os elementos, subsistemas, sistema e ambiente e, com isso, torna-se possível controlar o uso do método de forma iterativa. Para demonstrar tal uso, apresenta-se uma análise de um caso real e demonstra as dificuldades encontradas na utilização da Notação e Comunicação definida. Posteriormente, apresenta-se um desenho técnico de uma ferramenta computacional modular e que pode ser usada de forma integrada com outras ferramentas de outros métodos. Como resultado, têm-se o avanço na definição de padrões no uso das ferramentas do SSM, na apresentação dos aspectos sistêmicos do Planejamento Sistêmico, na apresentação de um uso iterativo do método e na apresentação de um desenho técnico para uma ferramenta computacional.

SSM samba: a survey of brazilian approaches to soft systems methodology (1999-2005)

This paper reports the results of a survey intended to discover the manner in which Soft Systems Methodology (SSM) is understood and used in Brazil. The focus is upon SSM papers published in national and international journals, and conferences, incorporating a refereeing procedure. To be included in the survey, publications had to meet at least one of the following criteria: (a) authorship is clearly of Brazilian nationality; or, (b) authorship is affiliated to a Brazilian institution; or (c) application is set in Brazil. Similar surveys reporting on the United Kingdom, Australia and, to a lesser extent, Spain have been published previously in the literature. This paper, therefore, contributes to the growing international understanding and usage of SSM. Ultimately the paper serves as an initial map of the developing context in Brazilian SSM theory and practice.

Evolution of ethyl carbamate during Madeira wine ageing by GC-MS: a new methodology

Recently, ethyl carbamate (EC) was reclassified by the International Agency for Research on Cancer (IARC) as "probably carcinogenic to humans" and occurs mainly in fermented beverages. Nowadays many countries have set limit values for EC in alcoholic beverages. In this sense and taking into account the low concentrations found in alcoholic beverages, the scientific community has shown interest for the development of new analytical methods, whereby its simplification plays an important role in the EC control and prevention. Firstly, a simple, rapid and sensitive methodology was developed for the EC quantification in fortified wines by microextraction by packed sorbent (MEPS) with gas chromatography coupled with a mass spectrometer detector (GC-MS). This method showed good linearity (R2 = 0.999) and sensitivity (LOD = 1.5 μg/L). The accuracy of the method was assessed by means of repeatability and reproducibility (RSD < 7%). Moreover, a good recovery has been demonstrated (97 – 106%) as well as its applicability (16 fortified wines). Thus, the developed methodology has proven to be an excellent approach for routine quantification of EC in fortified wines. The EC evolution was also evaluated during a year and half of Madeira wine ageing submitted to two traditional ageing methods, estufagem and canteiro, in order to evaluate the formation kinetic. The results revealed that estufagem process increased the formation kinetic and promoted a linear increase of the EC concentration (R2 ≥ 0.977), proportionally to the ageing time (4 months). However, when the wines are firstly submitted to estufagem and then undergo canteiro ageing, the EC values remain almost constant during the following 14 months. The results suggest that estufagem does not seem to be the critical factor in the EC formation, but instead the amount of precursors in the medium.

Teacher education in Portugal: analysing changes using ATEE-RDC19 scenario methodology

This paper presents an overview of the development of teacher education in Portugal since the Revolution of 25 April 1974, which brought the country to democracy. Making use of the scenario model created by the ATEE-RDC19, it is an attempt to make clearer the hidden philosophies underlying the changes that are undertaken and show how teacher education has evolved from a romantic and idealistic social vision towards an ideology dictated by economic and selfish interests.