Oxidation kinetics of nickel nano crystallites obtained by controlled thermolysis of diaquabis(ethylenediamine) nickel(II) nitrate

The metal complex, [Ni(en)2(H2O)2](NO3)2 (en = ethylenediamine), was decomposed in a static furnace at 200 C by autogenous decomposition to obtain phase pure metallic nickel nanocrystallites. The nickel metal thus obtained was studied by XRD, IR spectra, SEM and CHN analysis. The nickel crystallites are in the nanometer range as indicated by XRD studies. The IR spectral studies and CHN analyses show that the surface is covered with a nitrogen containing species. Thermogravimetric mass gain shows that the product purity is high (93%). The formed nickel is stable and resistant to oxidation up to 350 C probably due to the coverage of nitrogen containing species. Activation energy for the oxidation of the prepared nickel nanocrystallites was determined by non-isothermal methods and was found to depend on the conversion ratio. The oxidation kinetics of the nickel crystallites obeyed a Johnson–Mehl–Avrami mechanism probably due to the special morphology and crystallite strain present on the metal.

Finite Element Analysis of Warship Structures

Warships are generally sleek, slender with V shaped sections and block coefficient below 0.5, compared to fuller forms and higher values for commercial ships. They normally operate in the higher Froude number regime, and the hydrodynamic design is primarily aimed at achieving higher speeds with the minimum power. Therefore the structural design and analysis methods are different from those for commercial ships. Certain design guidelines have been given in documents like Naval Engineering Standards and one of the new developments in this regard is the introduction of classification society rules for the design of warships.The marine environment imposes subjective and objective uncertainties on ship structure. The uncertainties in loads, material properties etc.,. make reliable predictions of ship structural response a difficult task. Strength, stiffness and durability criteria for warship structures can be established by investigations on elastic analysis, ultimate strength analysis and reliability analysis. For analysis of complicated warship structures, special means and valid approximations are required.Preliminary structural design of a frigate size ship has been carried out . A finite element model of the hold model, representative of the complexities in the geometric configuration has been created using the finite element software NISA. Two other models representing the geometry to a limited extent also have been created —- one with two transverse frames and the attached plating alongwith the longitudinal members and the other representing the plating and longitudinal stiffeners between two transverse frames. Linear static analysis of the three models have been carried out and each one with three different boundary conditions. The structural responses have been checked for deflections and stresses against the permissible values. The structure has been found adequate in all the cases. The stresses and deflections predicted by the frame model are comparable with those of the hold model. But no such comparison has been realized for the interstiffener plating model with the other two models.Progressive collapse analyses of the models have been conducted for the three boundary conditions, considering geometric nonlinearity and then combined geometric and material nonlinearity for the hold and the frame models. von Mises — lllyushin yield criteria with elastic-perfectly plastic stress-strain curve has been chosen. ln each case, P-Delta curves have been generated and the ultimate load causing failure (ultimate load factor) has been identified as a multiple of the design load specified by NES.Reliability analysis of the hull module under combined geometric and material nonlinearities have been conducted. The Young's Modulus and the shell thickness have been chosen as the variables. Randomly generated values have been used in the analysis. First Order Second Moment has been used to predict the reliability index and thereafter, the probability of failure. The values have been compared against standard values published in literature.

Konzeption eines generischen Vorgehensmodells zur strategieorientierten und partizipativen Einführung komplexer Softwaresysteme unter Berücksichtigung organisatorischer Gestaltungsprozesse

Die Dissertation befasst sich mit der Einführung komplexer Softwaresysteme, die, bestehend aus einer Kombination aus parametrisierter Standardsoftware gepaart mit Wettbewerbsvorteil sichernden Individualsoftwarekomponenten, keine Software-Engineering-Projekte im klassischen Sinn mehr darstellen, sondern einer strategieorientierten Gestaltung von Geschäftsprozessen und deren Implementierung in Softwaresystemen bedürfen. Die Problemstellung einer adäquaten Abwägung zwischen TCO-optimierender Einführung und einer gleichzeitigen vollständigen Unterstützung der kritischen Erfolgsfaktoren des Unternehmens ist hierbei von besonderer Bedeutung. Der Einsatz integrierter betriebswirtschaftlicher Standardsoftware, mit den Möglichkeiten einer TCO-Senkung, jedoch ebenfalls der Gefahr eines Verlustes von Alleinstellungsmerkmalen am Markt durch Vereinheitlichungstendenzen, stellt ein in Einführungsprojekten wesentliches zu lösendes Problem dar, um Suboptima zu vermeiden. Die Verwendung von Vorgehensmodellen, die sich oftmals an klassischen Softwareentwicklungsprojekten orientieren oder vereinfachte Phasenmodelle für das Projektmanagement darstellen, bedingt eine fehlende Situationsadäquanz in den Detailsituationen der Teilprojekte eines komplexen Einführungsprojektes. Das in dieser Arbeit entwickelte generische Vorgehensmodell zur strategieorientierten und partizipativen Einführung komplexer Softwaresysteme im betriebswirtschaftlichen Anwendungsbereich macht - aufgrund der besonders herausgearbeiteten Ansätze zu einer strategieorientierten Einführung, respektive Entwicklung derartiger Systeme sowie aufgrund der situationsadäquaten Vorgehensstrategien im Rahmen der Teilprojektorganisation � ein Softwareeinführungsprojekt zu einem Wettbewerbsfaktor stärkenden, strategischen Element im Unternehmen. Die in der Dissertation diskutierten Überlegungen lassen eine Vorgehensweise präferieren, die eine enge Verschmelzung des Projektes zur Organisationsoptimierung mit dem Softwareimplementierungsprozess impliziert. Eine Priorisierung der Geschäftsprozesse mit dem Ziel, zum einen bei Prozessen mit hoher wettbewerbsseitiger Priorität ein organisatorisches Suboptimum zu vermeiden und zum anderen trotzdem den organisatorischen Gestaltungs- und den Systemimplementierungsprozess schnell und ressourcenschonend durchzuführen, ist ein wesentliches Ergebnis der Ausarbeitungen. Zusätzlich führt die Ausgrenzung weiterer Prozesse vom Einführungsvorgang zunächst zu einem Produktivsystem, welches das Unternehmen in den wesentlichen Punkten abdeckt, das aber ebenso in späteren Projektschritten zu einem System erweitert werden kann, welches eine umfassende Funktionalität besitzt. Hieraus ergeben sich Möglichkeiten, strategischen Anforderungen an ein modernes Informationssystem, das die kritischen Erfolgsfaktoren eines Unternehmens konsequent unterstützen muss, gerecht zu werden und gleichzeitig ein so weit als möglich ressourcenschonendes, weil die Kostenreduktionsaspekte einer Standardlösung nutzend, Projekt durchzuführen. Ein weiterer wesentlicher Aspekt ist die situationsadäquate Modellinstanziierung, also die projektspezifische Anpassung des Vorgehensmodells sowie die situationsadäquate Wahl der Vorgehensweisen in Teilprojekten und dadurch Nutzung der Vorteile der verschiedenen Vorgehensstrategien beim konkreten Projektmanagement. Der Notwendigkeit der Entwicklung einer Projektorganisation für prototypingorientiertes Vorgehen wird in diesem Zusammenhang ebenfalls Rechnung getragen. Die Notwendigkeit der Unternehmen, sich einerseits mit starken Differenzierungspotenzialen am Markt hervorzuheben und andererseits bei ständig sinkenden Margen einer Kostenoptimierung nachzukommen, lässt auch in Zukunft das entwickelte Modell als erfolgreich erscheinen. Hinzu kommt die Tendenz zu Best-Of-Breed-Ansätzen und komponentenbasierten Systemen im Rahmen der Softwareauswahl, die eine ausgesprochen differenzierte Vorgehensweise in Projekten verstärkt notwendig machen wird. Durch die in das entwickelte Modell integrierten Prototyping-Ansätze wird der auch in Zukunft an Bedeutung gewinnenden Notwendigkeit der Anwenderintegration Rechnung getragen.

Gröbnerbasen in Ore-Algebren

In dieser Arbeit werden grundlegende Algorithmen für Ore-Algebren in Mathematica realisiert. Dabei entsteht eine Plattform um die speziellen Beschränkungen und Möglichkeiten dieser Algebren insbesondere im Zusammenhang mit Gröbnerbasen an praktischen Beispielen auszuloten. Im Gegensatz zu den existierenden Paketen wird dabei explizit die Struktur der Ore-Algebra benutzt. Kandri-Rody und Weispfenning untersuchten 1990 Verallgemeinerungen von Gröbnerbasen auf Algebren ordnungserhaltender Art (``algebras of solvable type''). Diese verhalten sich so, dass Buchbergers Algorithmus stets eine Gröbnerbasis findet. Es wird ein Beispiel gezeigt, an dem klar wird, dass es mehr Ore-Algebren ordnungserhaltender Art gibt als die in der Literatur stets betrachteten Operator-Algebren. Für Ore-Algebren ordnungserhaltender Art werden Algorithmen zu Gröbnerbasen implementiert. Anschließend wird der Gröbner-Walk für Ore-Algebren untersucht. Der Gröbner-Walk im kommutativen Fall wird mit einem instruktiven Beispiel vorgestellt. Dann wird zum nichtkommutativen Fall übergegangen. Es wird gezeigt, dass die Eigenschaft ordnungserhaltender Art zu sein, auf der Strecke zwischen zwei Ordnungen erhalten bleibt. Eine leichte Modifikation des Walks für Ore-Algebren wird implementiert, die im Erfolgsfall die Basis konvertiert und ansonsten abbricht. Es werden Beispiele angegeben, in denen der modifizierte Walk funktioniert sowie ein Beispiel analysiert, in dem er versagt.

Contratación atípica en el sector central de la administración pública colombiana (ministerios y departamentos administrativos)

El Estatuto General de Contratación colombiano (Ley 80 de 1993 y normas que lo aclaran, complementan y desarrollan), como desarrollo de los artículos 4 y 209 de la Constitución Política y como ejemplo de la implantación de nuevas maneras de entender el derecho administrativo, habilita a las entidades estatales sujetas al estatuto general de contratación, en aras de alcanzar sus fines constitucionales y legales, para acudir a contratos del derecho privado, plasmados en normas especiales y aquellos derivados del ejercicio de la autonomía de la voluntad, sin que ello se oponga al principio de legalidad, piedra angular del derecho público. No obstante esta autorización legal expresa, el uso de contratos atípicos es muy limitado.

Límites del ordenamiento ambiental del territorio al turismo: el caso del Aeropuerto Internacional en la Isla de Providencia

El presente trabajo comenzará por abordar los antecedentes históricos y la caracterización del grupo étnico raizal desde una perspectiva jurídica enfocada en el turismo, el medio ambiente y la especial protección nacional e internacional del grupo étnico para el caso de la isla de Providencia, Colombia. A continuación se realizará un análisis del fenómeno turístico, incluyendo aspectos relacionados con los estudios del turismo y el desarrollo sostenible de esta actividad. A partir de este análisis, se examinarán los antecedentes y las características del modelo actual de desarrollo turístico en el municipio de Providencia y Santa Catalina. En el marco de los resultados del análisis anterior, se realizará una exposición de los aspectos jurídicos relacionados con el ordenamiento ambiental del territorio en el caso de la ampliación y remodelación del Aeropuerto el Embrujo en zona amortiguadora del Parque Nacional Natural Old Providence and Mc Bean Lagoon. Por último se expondrán las conclusiones y algunas recomendaciones.

Aproximació històrica a l'educació especial a Catalunya: l'educació institucionalitzada en centres d'educació especial a les comarques de Girona (1873-1997)

Aquesta Tesi Doctoral se situa en l'àmbit dels estudis històrico-educatius. S'estructura a partir d'una aproximació a la història de l'educació especial de les persones amb discapacitat i contextualitzada a partir de l'educació institucionalitzada en centres d'educació especial, a les comarques de Girona, durant el període de 1873 fins a 1997. El primer centre es va crear el 1873. Li seguiran, molts més anys més tard, altres iniciatives que sorgeixen a través de l'impuls de professionals i associacions de pares. L'Església participarà a través dels seus mossens i ordes religioses en la creació d'alguns d'aquests centres. L'administració educativa també assumirà un important paper en la creació, manteniment i consolidació dels centres. Aportem un important estudi sobre la legislació que va aparèixer al llarg d'aquest període. El punt final, el situem el 1997, a partir de la publicació per part del Department d'Ensenyament, del Decret 299/1997, de 25 de novembre, sobre l'atenció educativa a l'alumnat amb NEE.

A trilogia do sucesso: a educação inclusiva, a investigação-acção e a intervenção no grupo, atendendo à sua diversidade

RESUMO: O presente trabalho de projecto teve como principal objectivo compreender de que modo se pode promover o sucesso de todos, através do sucesso de cada um, num grupo heterogéneo de crianças do 2º e 3º ano do 1º Ciclo, com diferentes níveis de aprendizagem e problemáticas diversificadas. Com o principal objectivo de provocar mudanças positivas na dinâmica e intervenientes deste contexto, adoptou-se a metodologia de investigação-acção e recorreu-se a técnicas de pesquisa documental, à entrevista semi-directiva, à observação naturalista e à sociometria. O processo interventivo seguiu um plano de acção, inicialmente delimitado face às problemáticas diagnosticadas. Realizou-se de Fevereiro a Junho de 2010 seguindo uma estrutura cíclica e em espiral, composto por etapas de planificação, acção, avaliação e reflexão, para nova acção, que se tornou progressivamente mais informada. Esta metodologia permitiu alcançar resultados muito positivos e mudanças importantes no contexto intervencionado. Especificamente, numa fase inicial, a turma apresentava baixos desempenhos sociais, relacionais, comportamentais e académicos. Conjugados com estas problemáticas, todos os alunos apresentavam uma baixa autonomia, auto-estima e motivação para o processo de ensino-aprendizagem. Para além destes factores, apesar da heterogeneidade do grupo, de onde se destacavam os alunos 5, 9, 11, 12 e 13, considerados com necessidades educativas especiais, a dinâmica da prática pedagógica desenvolvida assentava num modelo de ensino tradicional, centrado no professor e nos desempenhos do aluno médio, reveladora de uma baixa eficiência de resultados. A heterogeneidade da turma era encarada como um obstáculo à aprendizagem. A intervenção desenvolvida, de forma fundamentada, permitiu um ensino inclusivo na turma, suportado na diferenciação pedagógica inclusiva, alcançada através da aprendizagem cooperativa, da tutoria entre pares e de uma estrutura coesa de parceria pedagógica entre a professora titular da turma e a investigadora. Para além destes, a intervenção realizada permitiu resultados positivos ao nível do perfil do grupo-turma, nomeadamente pelo registo de uma melhoria muito significativa nos desempenhos cognitivos, sócio-afectivos e comportamentais dos alunos. ABSTRACT: The present project work had as main objective to understand the way one can promote the success of all through the success of each one in a heterogeneous group of children of the 2nd and 3rd years of the 1st Cycle with different levels of learning and several problematic. With the main purpose of causing positive changes in the dynamics and actors of this context, the action-research methodology was adopted as well as the techniques of documentary research, and the half-directive interview, the naturalistic observation and the sociometry. The intervention process followed an action plan, initially delimited face to the problematic ones diagnosed. It took place from February to June 2010 following a cyclical and spiral structure made of stages of planning, action, evaluation and reflection, to a new action that became gradually more informed. This methodology allowed to reach very positive results and important changes in the interventional context. Specifically, in an initial phase, the group presented low social, relational, behavioral and academics performances. Together with these problematic issues, all the pupils presented a low autonomy, low self-esteem and low motivation for the teach-learning process. In addition to these factors there was the heterogeneity of the group (a group of pupils 5, 9, 11, 12 and 13 considered with special needs), and the teaching process was based on a traditional model centered in the teacher and the performances of the average pupil, revealing a low efficiency of results. The heterogeneity of the group was faced as an obstacle to the learning process. The developed intervention allowed an inclusive educational model in the group based in the inclusive pedagogical differentiation, reached through the cooperative learning, peer tutoring and a cohesive structure of pedagogical partnership between the titular teacher of the group and the researcher. Beyond these aspects, the research allowed positive results in the class, mainly a significant improvement in the cognitive, socio-emotional and behavioral performances of the pupils.

Colaboração entre Agentes Educativos num caso de dificuldades de Aprendizagem Específicas no 1º Ciclo do Ensino Básico

Nowadays we live in a literate society in which reading and writing skills are highly valued. Currently, the educational interventions seek to involve people from different backgrounds to form multidisciplinary teams. The present case study aimed to analyze the collaboration process between the different members of the context involved in educational intervention regarding the oral language disorders and learning disabilities in reading and writing. Concerning psychological evaluation we used different instruments for data collection. Firstly interview and clinical history where carried out afterwards a semi-structured interviews were prepared in order to obtain information about the performance of the special education team, the special education and children with special needs and learning difficulties in pre-primary and 1st cycle of basic education. The implementation of educational policies at the school where also considered in the case study which revealed difficulties in achieving the educational support for students with these problems.

Valorizar as diferenças na sala do 1º ciclo, abrir janelas de oportunidades para uma escola rica em aprendizagens e em humanidade

O presente relatório recapitula as diversas etapas de um trabalho de projeto de investigação-ação, no âmbito do Mestrado em Educação Especial - Domínio Cognitivo e Motor. Com ele pretendeu-se elaborar uma investigação-ação numa turma do 1º ciclo de escolaridade onde dois alunos sentiam grandes dificuldades de integração. A rejeição e a indiferença em que viviam provocavam, consequentemente, grandes dificuldades de aprendizagens académicas. O foco principal deste trabalho foi o desenvolvimento da interação dos alunos, promovendo a troca de saberes pela entreajuda. Daí resultaram os sucessos escolares esperados dos dois alunos visados a que se juntou a dinamização de todos os alunos da turma e dos restantes intervenientes educativos, professores, técnicos, encarregados de educação e comunidade escolar na construção efetiva de uma verdadeira escola inclusiva. Valorizaram-se as diferenças como património comum. Na fundamentação teórica deste projeto abordam-se a educação inclusiva e suas respetivas estratégias, a aprendizagem cooperativa, as dificuldades específicas de aprendizagem, a inter/multiculturalidade e o modelo pedagógico do Movimento da Escola Moderna como estrutura organizativa da intervenção. De seguida, é caracterizado o projeto e a situação inicial onde se interveio, referenciando o plano de ação implementado. As reflexões conclusivas evidenciam que trabalhar em cooperação permite progressos por parte de todos, tanto a nível das aprendizagens académicas como a nível da interação social.

A follow-up study of the academic achievement of hearing impaired children

This paper discusses a study to evaluate the academic progress of former students from CID including those who remained in special programs and those who were mainstreamed into regular public schools.

A phylogenetic mixture model for detecting pattern-heterogeneity in gene sequence or character-state data

We describe a general likelihood-based 'mixture model' for inferring phylogenetic trees from gene-sequence or other character-state data. The model accommodates cases in which different sites in the alignment evolve in qualitatively distinct ways, but does not require prior knowledge of these patterns or partitioning of the data. We call this qualitative variability in the pattern of evolution across sites "pattern-heterogeneity" to distinguish it from both a homogenous process of evolution and from one characterized principally by differences in rates of evolution. We present studies to show that the model correctly retrieves the signals of pattern-heterogeneity from simulated gene-sequence data, and we apply the method to protein-coding genes and to a ribosomal 12S data set. The mixture model outperforms conventional partitioning in both these data sets. We implement the mixture model such that it can simultaneously detect rate- and pattern-heterogeneity. The model simplifies to a homogeneous model or a rate- variability model as special cases, and therefore always performs at least as well as these two approaches, and often considerably improves upon them. We make the model available within a Bayesian Markov-chain Monte Carlo framework for phylogenetic inference, as an easy-to-use computer program.

Methylxanthines are the psycho-pharmacologically active constituents of chocolate

Rationale: Liking, cravings and addiction for chocolate ("chocoholism") are often explained through the presence of pharmacologically active compounds. However, mere "presence" does not guarantee psycho-activity. Objectives: Two double-blind, placebo-controlled studies measured the effects on cognitive performance and mood of the amounts of cocoa powder and methylxanthines found in a 50 g bar of dark chocolate. Methods: In study 1, participants (n=20) completed a test battery once before and twice after treatment administration. Treatments included 11.6 g cocoa powder and a caffeine and theobromine combination (19 and 250 mg, respectively). Study 2 (n=22) comprised three post-treatment test batteries and investigated the effects of "milk" and "dark" chocolate levels of these methylxanthines. The test battery consisted of a long duration simple reaction time task, a rapid visual information processing task, and a mood questionnaire. Results: Identical improvements on the mood construct "energetic arousal" and cognitive function were found for cocoa powder and the caffeine+theobromine combination versus placebo. In chocolate, both "milk chocolate" and "dark chocolate" methylxanthine doses improved cognitive function compared with "white chocolate". The effects of white chocolate did not differ significantly from those of water. Conclusion: A normal portion of chocolate exhibits psychopharmacological activity. The identical profile of effects exerted by cocoa powder and its methylxanthine constituents shows this activity to be confined to the combination of caffeine and theobromine. Methylxanthines may contribute to the popularity of chocolate; however, other attributes are probably much more important in determining chocolate's special appeal and in explaining related self-reports of chocolate cravings and "chocoholism".

Validation of the social communication questionnaire in a population cohort of children with autism spectrum disorders

Objective: To examine the properties of the Social Communication Questionnaire (SCQ) in a population cohort of children with autism spectrum disorders (ASDs) and in the general population, Method: SCQ data were collected from three samples: the Special Needs and Autism Project (SNAP) cohort of 9- to 10-year-old children with special educational needs with and without ASD and two similar but separate age groups of children from the general population (n = 411 and n = 247). Diagnostic assessments were completed on a stratified subsample (n = 255) of the special educational needs group. A sample-weighting procedure enabled us to estimate characteristics of the SCQ in the total ASD population. Diagnostic status of cases in the general population samples were extracted from child health records. Results: The SCQ showed strong discrimination between ASD and non-ASD cases (sensitivity 0.88, specificity 0.72) and between autism and nonautism cases (sensitivity 0.90, specificity 0.86). Findings were not affected by child IQ or parental education. In the general population samples between 4% and 5% of children scored above the ASD cutoff including 1.5% who scored above the autism cutoff. Although many of these high-scoring children had an ASD diagnosis, almost all (similar to 90%) of them had a diagnosed neurodevelopmental disorder. Conclusions: This study confirms the utility of the SCQ as a,first-level screen for ASD in at-risk samples of school-age children.

Inverse problems in dynamic cognitive modeling

Inverse problems for dynamical system models of cognitive processes comprise the determination of synaptic weight matrices or kernel functions for neural networks or neural/dynamic field models, respectively. We introduce dynamic cognitive modeling as a three tier top-down approach where cognitive processes are first described as algorithms that operate on complex symbolic data structures. Second, symbolic expressions and operations are represented by states and transformations in abstract vector spaces. Third, prescribed trajectories through representation space are implemented in neurodynamical systems. We discuss the Amari equation for a neural/dynamic field theory as a special case and show that the kernel construction problem is particularly ill-posed. We suggest a Tikhonov-Hebbian learning method as regularization technique and demonstrate its validity and robustness for basic examples of cognitive computations.