Framework for Enterprise Systems Engineering

This research aimed at developing a research framework for the emerging field of enterprise systems engineering (ESE). The framework consists of an ESE definition, an ESE classification scheme, and an ESE process. This study views an enterprise as a system that creates value for its customers. Thus, developing the framework made use of system theory and IDEF methodologies. This study defined ESE as an engineering discipline that develops and applies systems theory and engineering techniques to specification, analysis, design, and implementation of an enterprise for its life cycle. The proposed ESE classification scheme breaks down an enterprise system into four elements. They are work, resources, decision, and information. Each enterprise element is specified with four system facets: strategy, competency, capacity, and structure. Each element-facet combination is subject to the engineering process of specification, analysis, design, and implementation, to achieve its pre-specified performance with respect to cost, time, quality, and benefit to the enterprise. This framework is intended for identifying research voids in the ESE discipline. It also helps to apply engineering and systems tools to this emerging field. It harnesses the relationships among various enterprise aspects and bridges the gap between engineering and management practices in an enterprise. The proposed ESE process is generic. It consists of a hierarchy of engineering activities presented in an IDEF0 model. Each activity is defined with its input, output, constraints, and mechanisms. The output of an ESE effort can be a partial or whole enterprise system design for its physical, managerial, and/or informational layers. The proposed ESE process is applicable to a new enterprise system design or an engineering change in an existing system. The long-term goal of this study aims at development of a scientific foundation for ESE research and development.

Remoção de metais utilizando o hexadecanoato de sódio

Industrial activities like mining, electroplating and the oil extraction process, are increasing the levels of heavy metals such as Cu, Fe, Mg and Cd in aquatic ecosystems. This increase is related to the discharge of effluents containing trace of this elements above the maximum allowed by law. Methods such as ion exchange, membrane filtration and chemical precipitation have been studied as a means of treatment of these metals contamination. The precipitation of metals using anionic surfactants derived from carboxylic acids emerged as an alternative for the removal of metals from industrial effluents. The reaction between bivalent ions and these types of surfactants in aqueous solution leads to the formation of metal carboxylates, which can precipitate in the form of flakes and are subsequently removed by a process of decantation or simple filtration. In this work the metals extraction is performed by using the surfactant sodium hexadecanoate as extracting agent. The main purpose was to study the effect of temperature, solution pH, and concentration of surfactant in the metal removal process. The statistical design of the process showed that the process is directly dependent to changes in pH and concentration of surfactant, but inversely proportional and somewhat dependent to temperature variation, with the latter effect being considered negligible in most cases. The individual study of the effect of temperature showed a strong dependence of the process with the Kraft point, both for the surfactant used as extracting agent, as for the surfactant obtained after the reaction of this surfactant with the metal. From data of temperatures and concentrations of the surfactant was possible to calculate the equilibrium constant for the reaction between sodium hexadecanoate and copper ions. Later, thermodynamic parameters were determined, showing that the process is exothermic and spontaneous.

Conception, fabrication et caractérisation d'un biocapteur SPR à base de guides d'ondes photoniques sur substrat de verre

Résumé : Malgré le nombre croissant de capteurs dans les domaines de la chimie et la biologie, il reste encore à étudier en profondeur la complexité des interactions entre les différentes molécules présentes lors d’une détection à l’interface solide-liquide. Dans ce cadre, il est de tout intérêt de croiser différentes méthodes de détection afin d’obtenir des informations complémentaires. Le principal objectif de cette étude est de dimensionner, fabriquer et caractériser un détecteur optique intégré sur verre basé sur la résonance plasmonique de surface, destiné à terme à être combiné avec d’autres techniques de détection, dont un microcalorimètre. La résonance plasmonique de surface est une technique reconnue pour sa sensibilité adaptée à la détection de surface, qui a l’avantage d’être sans marquage et permet de fournir un suivi en temps réel de la cinétique d’une réaction. L’avantage principal de ce capteur est qu’il a été dimensionné pour une large gamme d’indice de réfraction de l’analyte, allant de 1,33 à 1,48. Ces valeurs correspondent à la plupart des entités biologiques associées à leurs couches d’accroche dont les matrices de polymères, présentés dans ce travail. Étant donné que beaucoup d’études biologiques nécessitent la comparaison de la mesure à une référence ou à une autre mesure, le second objectif du projet est d’étudier le potentiel du système SPR intégré sur verre pour la détection multi-analyte. Les trois premiers chapitres se concentrent sur l’objectif principal du projet. Le dimensionnement du dispositif est ainsi présenté, basé sur deux modélisations différentes, associées à plusieurs outils de calcul analytique et numérique. La première modélisation, basée sur l’approximation des interactions faibles, permet d’obtenir la plupart des informations nécessaires au dimensionnement du dispositif. La seconde modélisation, sans approximation, permet de valider le premier modèle approché et de compléter et affiner le dimensionnement. Le procédé de fabrication de la puce optique sur verre est ensuite décrit, ainsi que les instruments et protocoles de caractérisation. Un dispositif est obtenu présentant des sensibilités volumiques entre 1000 nm/RIU et 6000 nm/RIU suivant l’indice de réfraction de l’analyte. L’intégration 3D du guide grâce à son enterrage sélectif dans le verre confère au dispositif une grande compacité, le rendant adapté à la cointégration avec un microcalorimètre en particulier. Le dernier chapitre de la thèse présente l’étude de plusieurs techniques de multiplexage spectral adaptées à un système SPR intégré, exploitant en particulier la technologie sur verre. L’objectif est de fournir au moins deux détections simultanées. Dans ce cadre, plusieurs solutions sont proposées et les dispositifs associés sont dimensionnés, fabriqués et testés.

Approche basée sur des patrons pour concevoir des logiciels d’enseignement adaptés aux technologies du Web

Les applications Web en général ont connu d’importantes évolutions technologiques au cours des deux dernières décennies et avec elles les habitudes et les attentes de la génération de femmes et d’hommes dite numérique. Paradoxalement à ces bouleversements technologiques et comportementaux, les logiciels d’enseignement et d’apprentissage (LEA) n’ont pas tout à fait suivi la même courbe d’évolution technologique. En effet, leur modèle de conception est demeuré si statique que leur utilité pédagogique est remise en cause par les experts en pédagogie selon lesquels les LEA actuels ne tiennent pas suffisamment compte des aspects théoriques pédagogiques. Mais comment améliorer la prise en compte de ces aspects dans le processus de conception des LEA? Plusieurs approches permettent de concevoir des LEA robustes. Cependant, un intérêt particulier existe pour l’utilisation du concept patron dans ce processus de conception tant par les experts en pédagogie que par les experts en génie logiciel. En effet, ce concept permet de capitaliser l’expérience des experts et permet aussi de simplifier de belle manière le processus de conception et de ce fait son coût. Une comparaison des travaux utilisant des patrons pour concevoir des LEA a montré qu’il n’existe pas de cadre de synergie entre les différents acteurs de l’équipe de conception, les experts en pédagogie d’un côté et les experts en génie logiciel de l’autre. De plus, les cycles de vie proposés dans ces travaux ne sont pas complets, ni rigoureusement décrits afin de permettre de développer des LEA efficients. Enfin, les travaux comparés ne montrent pas comment faire coexister les exigences pédagogiques avec les exigences logicielles. Le concept patron peut-il aider à construire des LEA robustes satisfaisant aux exigences pédagogiques ? Comme solution, cette thèse propose une approche de conception basée sur des patrons pour concevoir des LEA adaptés aux technologies du Web. Plus spécifiquement, l’approche méthodique proposée montre quelles doivent être les étapes séquentielles à prévoir pour concevoir un LEA répondant aux exigences pédagogiques. De plus, un répertoire est présenté et contient 110 patrons recensés et organisés en paquetages. Ces patrons peuvent être facilement retrouvés à l’aide du guide de recherche décrit pour être utilisés dans le processus de conception. L’approche de conception a été validée avec deux exemples d’application, permettant de conclure d’une part que l’approche de conception des LEA est réaliste et d’autre part que les patrons sont bien valides et fonctionnels. L’approche de conception de LEA proposée est originale et se démarque de celles que l’on trouve dans la littérature car elle est entièrement basée sur le concept patron. L’approche permet également de prendre en compte les exigences pédagogiques. Elle est générique car indépendante de toute plateforme logicielle ou matérielle. Toutefois, le processus de traduction des exigences pédagogiques n’est pas encore très intuitif, ni très linéaire. D’autres travaux doivent être réalisés pour compléter les résultats obtenus afin de pouvoir traduire en artéfacts exploitables par les ingénieurs logiciels les exigences pédagogiques les plus complexes et les plus abstraites. Pour la suite de cette thèse, une instanciation des patrons proposés serait intéressante ainsi que la définition d’un métamodèle basé sur des patrons qui pourrait permettre la spécification d’un langage de modélisation typique des LEA. L’ajout de patrons permettant d’ajouter une couche sémantique au niveau des LEA pourrait être envisagée. Cette couche sémantique permettra non seulement d’adapter les scénarios pédagogiques, mais aussi d’automatiser le processus d’adaptation au besoin d’un apprenant en particulier. Il peut être aussi envisagé la transformation des patrons proposés en ontologies pouvant permettre de faciliter l’évaluation des connaissances de l’apprenant, de lui communiquer des informations structurées et utiles pour son apprentissage et correspondant à son besoin d’apprentissage.

Numerical simulation of fresh SCC flow in wall and beam elements using flow dynamics models

Abstract : Recently, there is a great interest to study the flow characteristics of suspensions in different environmental and industrial applications, such as snow avalanches, debris flows, hydrotransport systems, and material casting processes. Regarding rheological aspects, the majority of these suspensions, such as fresh concrete, behave mostly as non-Newtonian fluids. Concrete is the most widely used construction material in the world. Due to the limitations that exist in terms of workability and formwork filling abilities of normal concrete, a new class of concrete that is able to flow under its own weight, especially through narrow gaps in the congested areas of the formwork was developed. Accordingly, self-consolidating concrete (SCC) is a novel construction material that is gaining market acceptance in various applications. Higher fluidity characteristics of SCC enable it to be used in a number of special applications, such as densely reinforced sections. However, higher flowability of SCC makes it more sensitive to segregation of coarse particles during flow (i.e., dynamic segregation) and thereafter at rest (i.e., static segregation). Dynamic segregation can increase when SCC flows over a long distance or in the presence of obstacles. Therefore, there is always a need to establish a trade-off between the flowability, passing ability, and stability properties of SCC suspensions. This should be taken into consideration to design the casting process and the mixture proportioning of SCC. This is called “workability design” of SCC. An efficient and non-expensive workability design approach consists of the prediction and optimization of the workability of the concrete mixtures for the selected construction processes, such as transportation, pumping, casting, compaction, and finishing. Indeed, the mixture proportioning of SCC should ensure the construction quality demands, such as demanded levels of flowability, passing ability, filling ability, and stability (dynamic and static). This is necessary to develop some theoretical tools to assess under what conditions the construction quality demands are satisfied. Accordingly, this thesis is dedicated to carry out analytical and numerical simulations to predict flow performance of SCC under different casting processes, such as pumping and tremie applications, or casting using buckets. The L-Box and T-Box set-ups can evaluate flow performance properties of SCC (e.g., flowability, passing ability, filling ability, shear-induced and gravitational dynamic segregation) in casting process of wall and beam elements. The specific objective of the study consists of relating numerical results of flow simulation of SCC in L-Box and T-Box test set-ups, reported in this thesis, to the flow performance properties of SCC during casting. Accordingly, the SCC is modeled as a heterogeneous material. Furthermore, an analytical model is proposed to predict flow performance of SCC in L-Box set-up using the Dam Break Theory. On the other hand, results of the numerical simulation of SCC casting in a reinforced beam are verified by experimental free surface profiles. The results of numerical simulations of SCC casting (modeled as a single homogeneous fluid), are used to determine the critical zones corresponding to the higher risks of segregation and blocking. The effects of rheological parameters, density, particle contents, distribution of reinforcing bars, and particle-bar interactions on flow performance of SCC are evaluated using CFD simulations of SCC flow in L-Box and T-box test set-ups (modeled as a heterogeneous material). Two new approaches are proposed to classify the SCC mixtures based on filling ability and performability properties, as a contribution of flowability, passing ability, and dynamic stability of SCC.

Dry grinding technology for automotive gears manufacturing: process modeling and optimization

The following thesis focused on the dry grinding process modelling and optimization for automotive gears production. A FEM model was implemented with the aim at predicting process temperatures and preventing grinding thermal defects on the material surface. In particular, the model was conceived to facilitate the choice of the grinding parameters during the design and the execution of the dry-hard finishing process developed and patented by the company Samputensili Machine Tools (EMAG Group) on automotive gears. The proposed model allows to analyse the influence of the technological parameters, comprising the grinding wheel specifications. Automotive gears finished by dry-hard finishing process are supposed to reach the same quality target of the gears finished through the conventional wet grinding process with the advantage of reducing production costs and environmental pollution. But, the grinding process allows very high values of specific pressure and heat absorbed by the material, therefore, removing the lubricant increases the risk of thermal defects occurrence. An incorrect design of the process parameters set could cause grinding burns, which affect the mechanical performance of the ground component inevitably. Therefore, a modelling phase of the process could allow to enhance the mechanical characteristics of the components and avoid waste during production. A hierarchical FEM model was implemented to predict dry grinding temperatures and was represented by the interconnection of a microscopic and a macroscopic approach. A microscopic single grain grinding model was linked to a macroscopic thermal model to predict the dry grinding process temperatures and so to forecast the thermal cycle effect caused by the process parameters and the grinding wheel specification choice. Good agreement between the model and the experiments was achieved making the dry-hard finishing an efficient and reliable technology to implement in the gears automotive industry.

A BEM model applied to failure analysis of multi-fractured structures

Due to manufacturing or damage process, brittle materials present a large number of micro-cracks which are randomly distributed. The lifetime of these materials is governed by crack propagation under the applied mechanical and thermal loadings. In order to deal with these kinds of materials, the present work develops a boundary element method (BEM) model allowing for the analysis of multiple random crack propagation in plane structures. The adopted formulation is based on the dual BEM, for which singular and hyper-singular integral equations are used. An iterative scheme to predict the crack growth path and crack length increment is proposed. This scheme enables us to simulate the localization and coalescence phenomena, which are the main contribution of this paper. Considering the fracture mechanics approach, the displacement correlation technique is applied to evaluate the stress intensity factors. The propagation angle and the equivalent stress intensity factor are calculated using the theory of maximum circumferential stress. Examples of multi-fractured domains, loaded up to rupture, are considered to illustrate the applicability of the proposed method. (C) 2011 Elsevier Ltd. All rights reserved.

Dissolution parameters for sodium diclofenac-containing hypromellose matrix tablet

Sodium diclofenac (SD) release from dosage forms has been studied under different conditions. However, no dissolution method that is discriminatory enough to reflect slight changes in formulation or manufacturing process, and which could be effectively correlated with the biological properties of the dosage form, has been reported. This study sought to develop three different formulae of SD-containing matrix tablets and to determine the effect of agitation speed in its dissolution profiles. F1, F2 and F3 formulations were developed using hypromellose (10, 20 and 30%, respectively for F1, F2 and F3) and other conventional excipients. Dissolution tests were carried out in phosphate buffer pH 6.8 at 37 degrees C using apparatus 11 at 50, 75 or 100 rpm. Dissolution efficiency (DE), T(50) and T(90) were determined and plotted as functions of the variables agitation speed and hypromellose concentration. Regarding DE, F2 showed more sensitivity to variations in agitation speed than F1 and F3. Increasing hypromellose concentration reduced DE values, independent of agitation speed. Analysis of T(50) and T(90) suggests that F1 is less sensitive to variations in agitation speed than F2 and F3. Most discriminatory dissolution conditions were observed at 50 rpm. Results suggest that the comparison of dissolution performance of SD matrix tablets should take into account polymer concentration and agitation conditions. (C) 2009 Published by Elsevier B.V.

The GHEP-EMPOP collaboration on mtDNA population data-A new resource for forensic casework

Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from Sao Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP-EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Evidence for the presence of a widespread PCDD source in coastal sediments and soils from Queensland, Australia

Recent studies have demonstrated the occurrence of elevated levels of higher chlorinated PCDDs in the coastal environment of Queensland, Australia. This study presents new data for OCDD contamination and full PCDD/F profile analysis in the environment of Queensland. Marine sediments, irrigation drain sediments and topsoil were collected from sites that were expected to be influenced by specific land-use types. High OCDD concentrations were associated mainly with sediments collected near the mouth of rivers which drain into large catchments in the tropical and subtropical regions. Further, analysis of sediments from irrigation drains could be clearly differentiated on the basis of OCDD contamination, with high concentrations in samples from sugarcane drains collected from coastal regions, and low concentrations in drain sediments from drier inland cotton growing areas. PCDD/F congener-specific analysis demonstrated almost identical congener profiles in all samples collected along the coastline. This indicates the source to be widespread. Profiles were dominated by higher chlorinated PCDDs, in particular OCDD whereas 2,3,7,8-substituted PCDFs were below the limit of quantification in the majority of samples. The full PCDD/F profile analysis of samples strongly resemble those reported for lake sediments from Mississippi and kaolinite samples from Germany, Strong similarities to these samples with respect to congener profiles and isomer patterns may indicate the presence of a similar source and/or formation process that is yet unidentified. (C) 2001 Elsevier Science Ltd. All rights reserved.

Using workflow technology to manage flexible e-learning services

Workflow technology provides a suitable platform to define and manage the coordination of business process activities. We introduce a flexible e-learning environment – called Flex-eL – that has been built upon workflow technology. The workflow functionality of Flex-eL manages the coordination of learning and assessment activities of the course process between students and teaching staff. It provides a unique environment for teachers to design and develop process-centric courses and to monitor student progress. It allows students to learn at their own pace while observing the learning guidelines and checkpoints modeled into the course process by teaching staff. We also report on the successful deployment of the concept and system for university courses and our experiences from the implementation.

Amylases in enzyme detergents and their effects on a simulated long-life dairy dessert

Enzyme detergents used in the food industry contain proteinase as the major enzyme but amylase may be present, either by design or inadvertently. Three commercial enzyme detergents and 3 enzyme preparations used in detergents were assayed for alpha-amylase activity by the Ceralpha method using the Megazyme kits. The amylase activities of the detergents varied from 3.2x 10(-6) to 32x 10(-6) mumoles ml(-1) h(-1) while the enzyme preparations had much higher activities ranging from 0.05 to 8.06 mumoles ml(-1) h(-1). When added aseptically to a simulated dairy dessert (2% starch solution) and stored for 42 days, the enzyme detergents caused an increase in viscosity; enzyme preparations at low concentrations caused an initial increase in viscosity followed by a decrease; and enzyme preparations at high concentrations caused an immediate decrease in viscosity. The increase in viscosity corresponded to formation of a distinct network of starch granules while the decrease in viscosity was characterised by a marked decrease in size of the granules and little or no network of granules. Decreases in viscosity corresponded to increases in reducing sugars but samples which increased in viscosity showed no measurable reducing sugars. The amylase activity in all sources was destroyed by heating at 75degreesC for 15 min at pH 1.8.

Slicing for architectural analysis

Current software development often relies on non-trivial coordination logic for combining autonomous services, eventually running on different platforms. As a rule, however, such a coordination layer is strongly woven within the application at source code level. Therefore, its precise identification becomes a major methodological (and technical) problem and a challenge to any program understanding or refactoring process. The approach introduced in this paper resorts to slicing techniques to extract coordination data from source code. Such data are captured in a specific dependency graph structure from which a coordination model can be recovered either in the form of an Orc specification or as a collection of code fragments corresponding to the identification of typical coordination patterns in the system. Tool support is also discussed

Extracting and verifying coordination models from source code

Current software development relies increasingly on non-trivial coordination logic for com- bining autonomous services often running on di erent platforms. As a rule, however, in typical non-trivial software systems, such a coordination layer is strongly weaved within the application at source code level. Therefore, its precise identi cation becomes a major methodological (and technical) problem which cannot be overestimated along any program understanding or refactoring process. Open access to source code, as granted in OSS certi cation, provides an opportunity for the devel- opment of methods and technologies to extract, from source code, the relevant coordination information. This paper is a step in this direction, combining a number of program analysis techniques to automatically recover coordination information from legacy code. Such information is then expressed as a model in Orc, a general purpose orchestration language

Caracterização mecânica de misturas betuminosas a aplicar em infra-estruturas de transportes

A maioria das infra-estruturas de transportes, nomeadamente os pavimentos rodoviários e aeroportuários, são constituídas por misturas betuminosas, o que permite um bom desempenho e uma adequada durabilidade, nas condições usuais de serviço. As misturas betuminosas são ainda amplamente utilizadas na construção de zonas de estacionamento de veículos, tendo-se verificado recentemente a sua aplicação também em infra-estruturas ferroviárias. Face à necessidade de melhorar o desempenho das vias-férreas, permitindo uma concepção mais durável de linhas de alta velocidade e uma redução dos custos da sua manutenção, tem-se vindo a desenvolver diversos estudos para promover a utilização de novos materiais, principalmente através da incorporação de misturas betuminosas. O presente trabalho tem como objectivo a caracterização do comportamento mecânico de misturas betuminosas a aplicar em infra-estruturas de transportes. Como metodologia para o estudo do comportamento mecânico das misturas betuminosas foram realizados em laboratório ensaios de cargas repetidas, nomeadamente, ensaios de flexão em quatro pontos para determinação da rigidez e da resistência à fadiga e ensaios de compressão triaxiais cíclicos para avaliação do comportamento à deformação permanente. A resistência à fadiga das misturas betuminosas em estudo foi avaliada através do ensaio de flexão em quatro pontos, com extensão controlada, e aplicação de um carregamento sinusoidal com diferentes frequências, de acordo com o procedimento de ensaio da norma europeia EN 12697-24 (2004 + A1: 2007). A resistência à deformação permanente das misturas betuminosas foi analisada através de ensaios de compressão triaxiais cíclicos, submetendo-as a uma tensão de confinamento estática pela aplicação parcial de vácuo e a uma pressão axial cíclica sob a forma rectangular, de acordo com a norma europeia EN 12697-25 (2004). O conhecimento destas propriedades mecânicas assume particular importância ao nível da formulação das misturas betuminosas, do dimensionamento de uma estrutura ou do estabelecimento de uma adequada solução para uma obra de reabilitação duma infra-estrutura de transportes. Para este estudo foi utilizado um modelo físico construído numa fossa no LNEC, com o propósito de serem testadas três substruturas ferroviárias não convencionais, utilizando sub-balastro betuminoso. A selecção das substruturas foi efectuada após uma análise de várias secções de estruturas já testadas e aplicadas noutros países, de forma a proporcionar comparações fiáveis entre elas. Os resultados obtidos mostraram que a mistura betuminosa AC20 base 50/70 (MB) aplicada na camada de sub-balastro é adequada para ser aplicada nas infra-estruturas de transportes pois apresenta um bom desempenho à fadiga e à deformação permanente. Através dos ensaios efectuados foi ainda possível entender a importante influência das características volumétricas, principalmente da porosidade para o bom comportamento da mistura betuminosa.