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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Konzeptionelle Patterns und ihre Darstellung

Gröne, Bernhard January 2004 (has links)
Zur Beherrschung großer Systeme, insbesondere zur Weitergabe und Nutzung von Erfahrungswissen in der frühen Entwurfs- und Planungsphase, benötigt man Abstraktionen für deren Strukturen. Trennt man Software- von Systemstrukturen, kann man mit letzteren Systeme auf ausreichend hohem Abstraktionsgrad beschreiben.<br><br>Software-Patterns dienen dazu, Erfahrungswissen bezüglich programmierter Systeme strukturiert weiterzugeben. Dabei wird unterschieden zwischen Idiomen, die sich auf Lösungen mit einer bestimmten Programmiersprache beziehen, Design-Patterns, die nur einen kleinen Teil des Programms betreffen und Architektur-Patterns, deren Einfluss über einen größeren Teil oder gar das komplette Programm reicht. <br><br>Eine Untersuchung von existierenden Patterns zeigt, dass deren Konzepte nützlich zum Finden von Systemstrukturen sind. Die grafische Darstellung dieser Patterns ist dagegen oft auf Software-Strukturen eingeschränkt und ist für die Vermittlung von Erfahrungen zum Finden von Systemstrukturen meist nicht geeignet. <br><br>Daher wird die Kategorie der konzeptionellen Patterns mit einer darauf abgestimmten grafischen Darstellungsform vorgeschlagen, bei denen Problem und Lösungsvorschlag im Bereich der Systemstrukturen liegen. Sie betreffen informationelle Systeme, sind aber nicht auf Lösungen mit Software beschränkt. Die Systemstrukturen werden grafisch dargestellt, wobei dafür die Fundamental Modeling Concepts (FMC) verwendet werden, die zur Darstellung von Systemstrukturen entwickelt wurden. / Planning large and complex software systems is an important task of a system architect. It includes communicating with the customer, planning the overall system structure as well as preparing the division of labor among software engineers. What's more, a system architect benefits from other professionals' experiences concerning system architecture. By separating system from software structures, one can now describe a system by its system structure on an adequate level of abstraction. <br><br>Patterns provide a common form for the transfer of experiences. A pattern describes a widely used and proven solution to a problem that occurs in a certain context. <br><br>A study of existing architectural and design patterns shows that the concepts of many patterns carry valuable experiences concerning finding system structures. On the other hand, the graphical representations of these patterns usually focus on the software structures resulting from the solution in terms of classes and their relationships. This can be a problem if the solution doesn't imply one specific software structure but rather describes a concept which may be even independent from an implementation via software at all.<br><br>For that reason, Conceptual Patterns are introduced. A pattern can be called conceptual if both problem and solution concern system structures. Here, the functional aspects and structures of the system are relevant while code structures or even the use of software for implementation are not. To support the focus on system structures, terminology and notation of conceptual patterns should use an adequate means such as provided by the Fundamental Modeling Concepts (FMC).
2

The Study of Convergence of Telecom service company in Taiwan ¡Ð the View of sustainable competitive advantage

Cheng, Hung-yang 01 August 2008 (has links)
There are telecommunication industry and information industry to cost altogether, that is to communicate with each other according to industry development and technological gradual progress and fit Technological standardization, make the industry must use the fast development in the manufacturer, make the convergence of each boundary-less.Moreover different operation key different from resource foundation to can form difficult entry-barrier that cross over also ability way accumulated. Taiwan¡¦s ICT with the technological follower type, but with pursuing while growing up under large ship of the fast gradual progress of technology, how to adjust strategic resources, Represent brand-new institutional framework to create biggest customer's value with the business activity, it is a key topic.This research probes the mobile telecommunication industry, and base on digital-converge progression, focus on the enterprise behaviors produced under the third generation of mobile telecommunication data services and innovated. And Selected Key companies to analyze separately under the extension environment from competition advantage and Merger & Acquisition, and study through the description of the case. The result of study is found as follows: 􀁺 Three kind of convergence triggering business model changed. 􀁺 New technology of telecommunication created new mobile services. 􀁺 Strategical merger and acquisition changed telecommunication industrial structure.
3

[en] A COMPARISON OF CASCADE MULTITEMPORAL IMAGE CLASSIFICATION METHODS / [pt] COMPARAÇÃO DE MÉTODOS DE CLASSIFICAÇÃO MULTITEMPORAL EM CASCATA

LIGIA MARCELA TARAZONA ALVARADO 30 April 2019 (has links)
[pt] Esta dissertação faz uma comparação de três métodos de classificação em cascata de imagens multitemporais. Os classificadores se baseiam nas seguintes técnicas: (1) Máquina de Suporte Vetorial (SVM), (2) Modelos Ocultos de Markov (HMM) e (3) Cadeias de Markov Nebulosas(FMC). Para verificar a robustez dos modelos de classificação, introduziram-se nos dados de entrada outliers, avaliando-se assim, a robustez dos classificadores. Adicionalmente, avaliou-se o desempenho dos métodos quando a proporção de ocorrências de cada transição de classe no conjunto de treinamento difere da proporção no conjunto de teste. Determinou-se também qual o benefício do uso de conhecimento a priori sobre as transições possíveis. A análise experimental foi realizada sobre dois conjuntos de imagens de diferentes características, um par de imagens IKONOS do Rio de Janeiro, Brasil e um par de imagens LANDSAT7 de Alcinópolis, Mato Grosso do Sul. O estudo revelou que acurácia global das três abordagens tem um comportamento similar nos diferentes experimentos. Mostrou também que todas as três abordagens multitemporais apresentam desempenho superior aos seus homólogos monotemporais. / [en] This dissertation compares three cascade multitemporal image classification methods based on: (1) Support Vector Machines (SVM), (2) Hidden Markov Models (HMM) and (3) Fuzzy Markov Chains (FMC). The robustness of the classification models is verified, by introducing outliers in the data set. Additionally, performance of each method is evaluated when the number of occurrences of each class transition is different in the training and in the testing set. The gain of exploiting a prior knowledge regarding the admissible transitions in each target site is also investigated. The experimental analysis is conducted over two data sets with different characteristics; specifically a pair of IKONOS images of Rio de Janeiro and a pair of LANDSAT7 images of Alcinópolis, Mato Grosso do Sul. This study has concluded that the overall accuracy of the three approaches are similar through all experiments. The superiority ofthe multitemporal approaches over the monotemporal counterparts was confirmed.
4

Konzepte der Beschreibung interaktiver Systeme / Concepts of describing interactive systems

Knöpfel, Andreas January 2004 (has links)
Interaktive System sind dynamische Systeme mit einem zumeist informationellen Kern, die über eine Benutzungsschnittstelle von einem oder mehreren Benutzern bedient werden können. Grundlage für die Benutzung interaktiver Systeme ist das Verständnis von Zweck und Funktionsweise. Allein aus Form und Gestalt der Benutzungsschnittstelle ergibt sich ein solches Verständnis nur in einfachen Fällen. Mit steigender Komplexität ist daher eine verständliche Beschreibung solcher Systeme für deren Entwicklung und Benutzung unverzichtbar. <br><br> Abhängig von ihrem Zweck variieren die Formen vorgefundener Beschreibungen in der Literatur sehr stark. Ausschlaggebend für die Verständlichkeit einer Beschreibung ist jedoch primär die ihr zugrundeliegende Begriffswelt. Zur Beschreibung allgemeiner komplexer diskreter Systeme - aufbauend auf einer getrennten Betrachtung von Aufbau-, Ablauf- und Wertestrukturen - existiert eine bewährte Begriffswelt. Eine Spezialisierung dieser Begriffs- und Vorstellungswelt, die den unterschiedlichen Betrachtungsebenen interaktiver Systeme gerecht wird und die als Grundlage beliebiger Beschreibungsansätze interaktiver Systeme dienen kann, gibt es bisher nicht. <br><br> Ziel dieser Arbeit ist die Bereitstellung einer solchen Begriffswelt zur effizienten Kommunikation der Strukturen interaktiver Systeme. Dadurch soll die Grundlage für eine sinnvolle Ergänzung bestehender Beschreibungs- und Entwicklungsansätze geschaffen werden. Prinzipien der Gestaltung von Benutzungsschnittstellen, Usability- oder Ergonomiebetrachtungen stehen nicht im Mittelpunkt der Arbeit. <br><br> Ausgehend von der informationellen Komponente einer Benutzungsschnittstelle werden drei Modellebenen abgegrenzt, die bei der Betrachtung eines interaktiven Systems zu unterscheiden sind. Jede Modellebene ist durch eine typische Begriffswelt gekennzeichnet, die ihren Ursprung in einer aufbauverwurzelten Vorstellung hat. Der durchgängige Bezug auf eine Systemvorstellung unterscheidet diesen Ansatz von dem bereits bekannten Konzept der Abgrenzung unterschiedlicher Ebenen verschiedenartiger Entwurfsentscheidungen. Die Fundamental Modeling Concepts (FMC) bilden dabei die Grundlage für die Findung und die Darstellung von Systemstrukturen. <br><br> Anhand bestehender Systembeschreibungen wird gezeigt, wie die vorgestellte Begriffswelt zur Modellfindung genutzt werden kann. Dazu wird eine repräsentative Auswahl vorgefundener Systembeschreibungen aus der einschlägigen Literatur daraufhin untersucht, in welchem Umfang durch sie die Vorstellungswelt dynamischer Systeme zum Ausdruck kommt. Defizite in der ursprünglichen Darstellung werden identifiziert. Anhand von Alternativmodellen zu den betrachteten Systemen wird der Nutzen der vorgestellten Begriffswelt und Darstellungsweise demonstriert. / Interactive systems are dynamic systems which provide services to one or more users via a user interface. Many of these systems have an information processing core. To effectively use such a system, a user needs to know about the purpose and functional concepts of the system. Only in case of a rather simple functionality, the required knowledge is likely to be obtained by mere exploration of the user interface. For complex systems, a comprehensive description is essential for effective and efficient operation, but also for system development. Especially in the context of this publication, the focus is on the diagrams that are used for communication in the development process of interactive systems.<br><br> With regard to its purpose these descriptions vary in form and notation. In any case, it is the underlying terminology which is crucial to the understandability. Established concepts and notations for the description of generic information processing systems promote a strict separation of three categories of system structures: Compositional structures, behavioral structures and value-range structures.<br><br> This publication suggests a specialization of this approach for the description of interactive systems. The definition of specific notions and semantic layers is intended to provide a complement to existing description approaches in that field that constitutes a mental framework to enhance the efficiency of communication about interactive systems. In focusing to the description aspect only, design principles, system architectures and development methods are the context but not the subject of this work.<br><br> The separation of three semantic layers provides the foundation to distinguish purpose-related, interaction-related and implementation-related models of interactive systems. Each semantic layer is characterized by a specific terminology. Referring to the idea of equivalent models, the compositional system structure varies from layer to layer and provides the framework to ask for the observable behavior and values. The strict assignment of system aspects to system components distinguishes this approach from a simple layering of design decisions in the development of interactive systems as commonly found in the relevant literature. The Fundamental Modeling Concepts (FMC) provide the foundation for the identification and representation of system structures.<br><br> A selection of system descriptions taken from the relevant literature provides the starting point to demonstrate the application of the suggested concept. Purpose, content and form of each example are analyzed with regard to the implied system structure. Weaknesses in the original representation are identified. Alternative models complement the examples to illustrate the benefit of the new approach.
5

Quantitative modeling and analysis with FMC-QE

Kluth, Stephan January 2011 (has links)
The modeling and evaluation calculus FMC-QE, the Fundamental Modeling Concepts for Quanti-tative Evaluation [1], extends the Fundamental Modeling Concepts (FMC) for performance modeling and prediction. In this new methodology, the hierarchical service requests are in the main focus, because they are the origin of every service provisioning process. Similar to physics, these service requests are a tuple of value and unit, which enables hierarchical service request transformations at the hierarchical borders and therefore the hierarchical modeling. Through reducing the model complexity of the models by decomposing the system in different hierarchical views, the distinction between operational and control states and the calculation of the performance values on the assumption of the steady state, FMC-QE has a scalable applica-bility on complex systems. According to FMC, the system is modeled in a 3-dimensional hierarchical representation space, where system performance parameters are described in three arbitrarily fine-grained hierarchi-cal bipartite diagrams. The hierarchical service request structures are modeled in Entity Relationship Diagrams. The static server structures, divided into logical and real servers, are de-scribed as Block Diagrams. The dynamic behavior and the control structures are specified as Petri Nets, more precisely Colored Time Augmented Petri Nets. From the structures and pa-rameters of the performance model, a hierarchical set of equations is derived. The calculation of the performance values is done on the assumption of stationary processes and is based on fundamental laws of the performance analysis: Little's Law and the Forced Traffic Flow Law. Little's Law is used within the different hierarchical levels (horizontal) and the Forced Traffic Flow Law is the key to the dependencies among the hierarchical levels (vertical). This calculation is suitable for complex models and allows a fast (re-)calculation of different performance scenarios in order to support development and configuration decisions. Within the Research Group Zorn at the Hasso Plattner Institute, the work is embedded in a broader research in the development of FMC-QE. While this work is concentrated on the theoretical background, description and definition of the methodology as well as the extension and validation of the applicability, other topics are in the development of an FMC-QE modeling and evaluation tool and the usage of FMC-QE in the design of an adaptive transport layer in order to fulfill Quality of Service and Service Level Agreements in volatile service based environments. This thesis contains a state-of-the-art, the description of FMC-QE as well as extensions of FMC-QE in representative general models and case studies. In the state-of-the-art part of the thesis in chapter 2, an overview on existing Queueing Theory and Time Augmented Petri Net models and other quantitative modeling and evaluation languages and methodologies is given. Also other hierarchical quantitative modeling frameworks will be considered. The description of FMC-QE in chapter 3 consists of a summary of the foundations of FMC-QE, basic definitions, the graphical notations, the FMC-QE Calculus and the modeling of open queueing networks as an introductory example. The extensions of FMC-QE in chapter 4 consist of the integration of the summation method in order to support the handling of closed networks and the modeling of multiclass and semaphore scenarios. Furthermore, FMC-QE is compared to other performance modeling and evaluation approaches. In the case study part in chapter 5, proof-of-concept examples, like the modeling of a service based search portal, a service based SAP NetWeaver application and the Axis2 Web service framework will be provided. Finally, conclusions are given by a summary of contributions and an outlook on future work in chapter 6. [1] Werner Zorn. FMC-QE - A New Approach in Quantitative Modeling. In Hamid R. Arabnia, editor, Procee-dings of the International Conference on Modeling, Simulation and Visualization Methods (MSV 2007) within WorldComp ’07, pages 280 – 287, Las Vegas, NV, USA, June 2007. CSREA Press. ISBN 1-60132-029-9. / FMC-QE (Fundamental Modeling Concepts for Quantitative Evaluation [1]) ist eine auf FMC, den Fundamental Modeling Concepts, basierende Methodik zur Modellierung des Leistungsverhaltens von Systemen mit einem dazugehörenden Kalkül zur Erstellung von Leistungsvorhersagen wie Antwortzeiten und Durchsatz. In dieser neuen Methodik steht die Modellierung der hierarchischen Bedienanforderungen im Mittelpunkt, da sie der Ursprung aller dienstbasierenden Systeme sind. Wie in der Physik sind in FMC-QE die Bedienanforderungen Tupel aus Wert und Einheit, um Auftragstransformationen an Hierarchiegrenzen zu ermöglichen. Da die Komplexität durch eine Dekomposition in mehreren Sichten und in verschiedene hierarchische Schichten, die Unterscheidung von Operations- und Kontrollzuständen, sowie dazugehörige Berechungen unter Annahme der Stationarität reduziert wird, skaliert die Anwendbarkeit von FMC-QE auf komplexe Systeme. Gemäß FMC wird das zu modellierende System in einem 3-dimensionalen hierarchischen Beschreibungsraum dargestellt. Die quantitativen Kenngrößen der Systeme werden in drei beliebig frei-granularen hierarchischen bi-partiten Graphen beschrieben. Die hierarchische Struktur der Bedienanforderungen wird in Entity Relationship Diagrammen beschrieben. Die statischen Bedienerstrukturen, unterteilt in logische und reale Bediener, sind in Aufbaudiagrammen erläutert. Außerdem werden Petri Netze, genauer Farbige Zeit-behaftete Petri Netze, dazu verwendet, die dynamischen Abläufe, sowie die Kontrollflüsse im System zu beschreiben. Anschließend wird eine Menge von hierarchischen Gleichungen von der Struktur und den Parametern des Modells abgeleitet. Diese Gleichungen, die auf dem stationären Zustand des Systems beruhen, basieren auf den beiden Fundamental Gesetzen der Leistungsanalyse, dem Gesetz von Little und dem Verkehrsflussgesetz. Das Gesetz von Little definiert hierbei Beziehungen innerhalb einer hierarchischen Schicht (horizontal) und das Verkehrsflussgesetz wiederum Beziehungen zwischen hierarchischen Schichten (vertikal). Die Berechungen erlauben Leistungsvorhersagen für komplexe Systeme durch eine effiziente Berechnung von Leistungsgrößen für eine große Auswahl von System- und Lastkonfigurationen. Innerhalb der Forschungsgruppe von Prof. Dr.-Ing Werner Zorn am Hasso Plattner Institut an der Universität Potsdam ist die vorliegende Arbeit in einen größeren Forschungskontext im Bereich FMC-QE eingebettet. Während hier ein Fokus auf dem theoretischen Hintergrund, der Beschreibung und der Definition der Methodik als auch der Anwendbarkeit und Erweiterung gelegt wurde, sind andere Arbeiten auf dem Gebiet der Entwicklung einer Anwendung zur Modellierung und Evaluierung von Systemen mit FMC-QE bzw. der Verwendung von FMC-QE zur Entwicklung einer adaptiven Transportschicht zur Einhaltung von Dienstgüten (Quality of Service) und Dienstvereinbarungen (Service Level Agreements) in volatilen dienstbasierten Systemen beheimatet. Diese Arbeit umfasst einen Einblick in den Stand der Technik, die Beschreibung von FMC-QE sowie die Weiterentwicklung von FMC-QE in repräsentativen allgemeinen Modellen und Fallstudien. Das Kapitel 2: Stand der Technik gibt einen Überblick über die Warteschlangentheorie, Zeit-behaftete Petri Netze, weitere Leistungsbeschreibungs- und Leistungsvorhersagungstechniken sowie die Verwendung von Hierarchien in Leistungsbeschreibungstechniken. Die Beschreibung von FMC-QE in Kapitel 3 enthält die Erläuterung der Grundlagen von FMC-QE, die Beschreibung einiger Grundannahmen, der graphischen Notation, dem mathematischen Modell und einem erläuternden Beispiel. In Kapitel 4: Erweiterungen von FMC-QE wird die Behandlung weiterer allgemeiner Modelle, wie die Modellklasse von geschlossenen Netzen, Synchronisierung und Mehrklassen-Modelle beschrieben. Außerdem wird FMC-QE mit dem Stand der Technik verglichen. In Kapitel 5 werden Machbarkeitsstudien beschrieben. Schließlich werden in Kapitel 6 eine Zusammenfassung und ein Ausblick gegeben. [1] Werner Zorn. FMC-QE - A New Approach in Quantitative Modeling. In Hamid R. Arabnia, editor, Proceedings of the International Conference on Modeling, Simulation and Visualization Methods (MSV 2007) within WorldComp ’07, 280 – 287, Las Vegas, NV, USA, Juni 2007. CSREA Press. ISBN 1-60132-029-9.
6

Contrôle de la mobilité dans un réseau d'opérateur convergé fixe-mobile / Mobility management in a converged fixed-mobile operator's network

Eido, Souheir 12 July 2017 (has links)
Les réseaux fixes et mobiles font face à une croissance dramatique du trafic de données, qui est principalement due à la distribution de contenus vidéo. Les opérateurs Télécoms envisagent donc de décentraliser la distribution de contenus dans les futures architectures convergées fixe-mobile (FMC). Cette décentralisation, conjointement au déploiement d'un cœur de réseau mobile distribué, sera un élément majeur des futurs réseaux 5G. L'approche SIPTO définie par 3GPP permet déjà le délestage sur le réseau fixe du trafic mobile, et pourra donc être utilisée en 5G. SIPTO s'appuie sur la distribution des passerelles de données (PGW) qui permet ainsi de décharger le cœur du réseau mobile actuel. Cependant, dans certains cas de mobilité des usagers, SIPTO ne supporte pas la continuité de session, quand il est nécessaire de changer de PGW, donc de modifier l'adresse IP du terminal. Cette thèse commence par quantifier le gain apporté par le délestage du trafic mobile en termes de capacité requise pour différentes portions du réseau. Un état de l'art des différentes solutions de délestage du trafic de données mobiles est fourni, démontrant qu'aucune des solutions existantes ne supporte la continuité de service pour les sessions de longue durée. C'est pourquoi, cette thèse propose des solutions pour supporter une mobilité transparente ; ces solutions s'appuient à la fois sur SIPTO et sur le protocole MultiPath TCP (MPTCP). Les protocoles du 3GPP sont inchangés car la continuité est maintenue par les extrémités. Enfin, ces solutions sont appliquées aux différentes implémentations d'architectures FMC envisagées à ce jour. / Fixed and mobile networks are currently experiencing a dramatic growth in terms of data traffic, mainly driven by video content distribution. Telecoms operators are thus considering de-centralizing content distribution architecture for future Fixed and Mobile Converged (FMC) network architectures. This decentralization, together with a distributed mobile EPC, would be used for future 5G networks. Mobile data offloading, in particular SIPTO approaches, already represent a good implementation model for 5G network as it allows the use of distributed IP edges to offload Selected IP traffic off the currently centralized mobile core network. However, in some cases, SIPTO does not support session continuity during users' mobility. This is due to the fact that user's mobility may imply packet gateway (PGW) relocation and thus a modification of the UE's IP address.This PhD thesis first quantifies the gain, in terms of bandwidth demands on various network portions, brought by the generalized use of mobile traffic offloading. A state of art of existing mobile data offloading solutions is presented, showing that none of the existing solutions solve the problem of session continuity for long-lived sessions. This is why, in the context of future FMC mobile network architectures, the PhD thesis proposes solutions to provide seamless mobility for users relying on SIPTO with the help of Multipath TCP (MPTCP). 3GPP standards are not modified, as session continuity is ensured by end-points. Lastly, the proposed solutions are mapped on different architecture options considered for future FMC networks.
7

Das palavras aos quanta: analogia como elemento do pensamento e ferramenta didática em aulas de física quântica na educação básica / From words to Quanta: analogies on Quantum Physics Class

Hastenreiter, Roberto Soares da Cruz 24 August 2015 (has links)
O presente trabalho trata do uso de analogias em atividades didáticas voltadas às aulas de ciências e, mais especificamente, do uso de analogias em aulas sobre temas de física quântica para alunos do ensino médio. Partimos, então, da aparente contradição que resulta da tentativa de abordar conceitos da física quântica, conceitos estes abstratos e sem relação com a realidade sensível, por meio de um mecanismo representativo que é baseado na comparação entre dois domínios do conhecimento, no qual um deles pertence ao repertório do conhecido (familiar) e o outro diz respeito ao que se deseja conhecer. Nossa principal contribuição, ligada à nossa proposição inicial, se dá na medida em que propomos inicialmente reflexões a respeito do conceito de analogia em três dimensões: a primeira, associada à perspectiva da psicologia cognitiva, na qual a analogia se constitui como elemento central do pensamento e assim da formação dos conceitos em toda a história do sujeito; a segunda, relacionada à epistemologia da ciência, especificamente sob a perspectiva de Henri Poincaré, a partir da qual se apontam basicamente três categorias de analogias (figurativas, mecânicas e matemáticas); a terceira, ligada às atividades didáticas que consideram a analogia como ferramenta de aprendizagem, e que busca, a partir de esforços coletivos presentes na literatura especializada em ensino de ciências, sistematizar o seu uso. A partir de uma ampla leitura das três dimensões supracitadas, propomos uma síntese que nos permita um olhar específico para nosso objeto de pesquisa. A fim de analisar o potencial de nossa síntese teórica, realizamos um ensaio empírico que consistiu na elaboração de episódios criados a partir de aulas de temas de física quântica ministradas a alunos do ensino médio (modelos atômicos, efeito fotoelétrico, dualidade onda-partícula, interpretações da Mecânica Quântica). A metodologia usada na interpretação dos episódios pressupõe que analogias em atividades didáticas podem ser classificadas quanto ao seu nível de elaboração, assim como em aspectos ligados ao seu uso, como o formato de apresentação e de ações prévias. Os resultados nos ajudam a perceber situações de uso de analogias prioritariamente figurativas com alguns casos de analogias mecânicas. A ausência de uso de analogias matemáticas, assim como do formato de apresentação matemático-representativo, nos permite reafirmar o caráter crucial de se investigarem novos \"formatos\" de analogias que sejam adequados à comunicação e ao ensino de conceitos da física quântica. / This work deals with the use of analogies in teaching activities of sciences and, more specifically, with the use of analogies in high school quantum physics courses. Our starting point is the apparent contradiction of attempting to approach the concepts of quantum physics, abstract and deprived of any relation with the sensory reality, through a mechanism of representation based on the comparison of two fields knowledge: a first one which is known and familiar, and a second one which we wish to grasp. Our main contribution lies in our initial proposition to reflect on the concept of analogy from three different perspectives: first, there is the point of view of cognitive psychology, in which analogy appears as central element of thought and therefore of the formation of concepts during the whole history of the subject; second, there is the point of view of epistemology of science, and particularly that of Henri Poincaré who distinguished three basic categories for analogies (figurative, mechanical and mathematical); third, there is the point of view of educational activities, which considers analogies as a learning tool and attempts, through collective efforts manifested in the science education literature, to provide a systematic account of their use. Based on an ample reading along the three aforementioned dimensions, we then propose a synthesis enabling us to adopt a specific look at our object of research. In order to analyse the potential of this theoretical synthesis, we have conducted an empirical test constituted by episodes created within high school quantum physics lectures (atomic models, the photoelectric effect, the wave-particle duality, and the interpretations of Quantum Mechanics). In order to interpret these episodes, the methodology assumes that analogies in teaching activities can effectively be classified according to their level of development and to some aspects of their use, such as the presentation format and the previous actions. The results help us in perceiving how most of the analogies used are figurative, even though there are also some mechanical analogies. The lack of use of mathematical analogies, as well as the absence of the mathematical-representative presentation format, allows us to reaffirm the crucial need of investigating new \"formats\" of analogies, better suited for the communication and teaching of the concepts of quantum physics.
8

SUSCEPTIBILIDADE in vitro DE ISOLADOS DE Pythium insidiosum FRENTE A AMINOGLICOSÍDEOS E TIGECICLINA. / In vitro SUSCEPTIBILITY OF Pythium insidiosum ISOLATES TO AMIGLICOSIDES AND TIGECYCLINE.

Mahl, Deise Luiza 15 March 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pythiosis is a chronic disease that affects humans, other mammals and birds. It is caused by the aquatic oomycete Pythium insidiosum. Pythiosis progresses rapidly and can become life threatening if not treated in the early stages. The absence of ergosterol in the cell wall of this oomycete prevents the treatment of pythiosis with antifungal therapy because most antifungal drugs act by inhibiting the synthesis of ergosterol. Members of the genus Pythium are known to be susceptible to some antimicrobial of the tetracycline, macrolide, aminoglycoside and chloramphenicol classes. This study aimed to evaluate the in vitro susceptibility of isolates of P. insidiosum to the aminoglycosides gentamicin, neomycin, paromomycin and streptomycin and to the minocycline derivative tigecycline. The susceptibility tests were carried out with 24 P. insidiosum isolates using the broth microdilution method in accordance with Clinical and Laboratory Standards Institute (CLSI) document M38-A2. The minimum inhibitory concentration (MIC) values for gentamicin, neomycin, paromomycin and streptomycin ranged from 32 to 64 mg/L, and the minimal fungicidal concentration (MFC) values ranged from 32 to 128 mg/L. Tigecycline had a good inhibitory activity, with values of mic MIC (0.25-2 mg/L) and MFC (1-8 mg/L) values. The observed in vitro susceptibility to tigecycline makes this drug a good option for future in vivo assays investigating options of treatment of pythiosis. / Pitiose é uma doença crônica que afeta humanos, outros mamíferos e pássaros. O seu agente etiológico é um oomiceto aquático denominado Pythium insidiosum. A Pitiose evolui rapidamente e pode se tornar fatal se não tratada nos primeiros estágios. A ausência de ergosterol na parede da célula deste oomiceto impede o tratamento de pitiose com terapia antifúngica, pois a maioria das drogas antifúngicas atua sobre a síntese de ergosterol. Os membros do gênero Pythium são conhecidos por serem susceptíveis a alguns antimicrobianos do grupo das tetraciclinas, macrolídeos, aminoglicosídeos e cloranfenicol. Este estudo teve como objetivo avaliar a susceptibilidade in vitro de isolados de P. insidiosum frente aos aminoglicosídeos gentamicina, neomicina, paromomicina e estreptomicina e ao derivado da minociclina denominado de tigeciclina. Os testes de susceptibilidade foram realizados com 24 isolados de P. insidiosum, utilizando o método de microdiluição em caldo, de acordo com o documento M38- A2 do Clinical and Laboratory Standards Institute (CLSI). Os valores de Concentração Inibitória Mínima (CIM) de gentamicina, neomicina, paromomicina e estreptomicina variaram de 32 a 64 mg/L, e os valores de concentração fungicida mínima (CFM) variaram de 32 a 128 mg/l. Tigeciclina apresentou boa atividade inibitória, com valores de CIM (0,25-2 mg/L) e CFM (1-8 mg/L). A susceptibilidade à tigeciclina observada in vitro faz deste fármaco uma boa opção em futuros ensaios e in vivo, investigando o tratamento da pitiose.
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Das palavras aos quanta: analogia como elemento do pensamento e ferramenta didática em aulas de física quântica na educação básica / From words to Quanta: analogies on Quantum Physics Class

Roberto Soares da Cruz Hastenreiter 24 August 2015 (has links)
O presente trabalho trata do uso de analogias em atividades didáticas voltadas às aulas de ciências e, mais especificamente, do uso de analogias em aulas sobre temas de física quântica para alunos do ensino médio. Partimos, então, da aparente contradição que resulta da tentativa de abordar conceitos da física quântica, conceitos estes abstratos e sem relação com a realidade sensível, por meio de um mecanismo representativo que é baseado na comparação entre dois domínios do conhecimento, no qual um deles pertence ao repertório do conhecido (familiar) e o outro diz respeito ao que se deseja conhecer. Nossa principal contribuição, ligada à nossa proposição inicial, se dá na medida em que propomos inicialmente reflexões a respeito do conceito de analogia em três dimensões: a primeira, associada à perspectiva da psicologia cognitiva, na qual a analogia se constitui como elemento central do pensamento e assim da formação dos conceitos em toda a história do sujeito; a segunda, relacionada à epistemologia da ciência, especificamente sob a perspectiva de Henri Poincaré, a partir da qual se apontam basicamente três categorias de analogias (figurativas, mecânicas e matemáticas); a terceira, ligada às atividades didáticas que consideram a analogia como ferramenta de aprendizagem, e que busca, a partir de esforços coletivos presentes na literatura especializada em ensino de ciências, sistematizar o seu uso. A partir de uma ampla leitura das três dimensões supracitadas, propomos uma síntese que nos permita um olhar específico para nosso objeto de pesquisa. A fim de analisar o potencial de nossa síntese teórica, realizamos um ensaio empírico que consistiu na elaboração de episódios criados a partir de aulas de temas de física quântica ministradas a alunos do ensino médio (modelos atômicos, efeito fotoelétrico, dualidade onda-partícula, interpretações da Mecânica Quântica). A metodologia usada na interpretação dos episódios pressupõe que analogias em atividades didáticas podem ser classificadas quanto ao seu nível de elaboração, assim como em aspectos ligados ao seu uso, como o formato de apresentação e de ações prévias. Os resultados nos ajudam a perceber situações de uso de analogias prioritariamente figurativas com alguns casos de analogias mecânicas. A ausência de uso de analogias matemáticas, assim como do formato de apresentação matemático-representativo, nos permite reafirmar o caráter crucial de se investigarem novos \"formatos\" de analogias que sejam adequados à comunicação e ao ensino de conceitos da física quântica. / This work deals with the use of analogies in teaching activities of sciences and, more specifically, with the use of analogies in high school quantum physics courses. Our starting point is the apparent contradiction of attempting to approach the concepts of quantum physics, abstract and deprived of any relation with the sensory reality, through a mechanism of representation based on the comparison of two fields knowledge: a first one which is known and familiar, and a second one which we wish to grasp. Our main contribution lies in our initial proposition to reflect on the concept of analogy from three different perspectives: first, there is the point of view of cognitive psychology, in which analogy appears as central element of thought and therefore of the formation of concepts during the whole history of the subject; second, there is the point of view of epistemology of science, and particularly that of Henri Poincaré who distinguished three basic categories for analogies (figurative, mechanical and mathematical); third, there is the point of view of educational activities, which considers analogies as a learning tool and attempts, through collective efforts manifested in the science education literature, to provide a systematic account of their use. Based on an ample reading along the three aforementioned dimensions, we then propose a synthesis enabling us to adopt a specific look at our object of research. In order to analyse the potential of this theoretical synthesis, we have conducted an empirical test constituted by episodes created within high school quantum physics lectures (atomic models, the photoelectric effect, the wave-particle duality, and the interpretations of Quantum Mechanics). In order to interpret these episodes, the methodology assumes that analogies in teaching activities can effectively be classified according to their level of development and to some aspects of their use, such as the presentation format and the previous actions. The results help us in perceiving how most of the analogies used are figurative, even though there are also some mechanical analogies. The lack of use of mathematical analogies, as well as the absence of the mathematical-representative presentation format, allows us to reaffirm the crucial need of investigating new \"formats\" of analogies, better suited for the communication and teaching of the concepts of quantum physics.
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下一代網路資訊服務與系統供應商之成功經營模式研究

陳建宏, Chen, Chien Hung Unknown Date (has links)
下一代網路(Next Generation Network,NGN)是因應未來語音、數據、影像等Triple Play之資訊服務對頻寬與網路能力要求日益增加下所提出的一種新網路形態概念。同時,NGN以IP 多媒體子系統(IP Multimedia Subsystem,IMS)為其核心可以降低系統供應商的營運佈建成本。NGN強調的固網行動融合(Fixed Mobile Convergence,FMC)與全IP網路(All IP Network)化以及強化服務品質(Quality of Service,QoS)精神,都使資訊服務與系統供應業者需要思考出一套新的經營模式(Business Model),使其能在NGN上獲利。本研究之主要目的為以NGN的架構與特性為出發,剖析此一網路的數位匯流趨勢與其成功經營模式研究。 本研究採個案研究法(Case Study Method),透過次級資料的蒐集以及與本研究有關之文獻探討的方式,找出未來NGN的經營模式形貌,並透過訪談相關業者來佐證本研究所提出經營模式之合理性。 由於資訊服務產業範圍廣泛,故本研究選定VoIP及IPTV為主要研究對象,期盼能找出一套適合在NGN上獲利的模式。另外針對企業用戶,NGN也能協助企業增加競爭力,在商業情報的取得、溝通成本的降低、資訊管理系統等都能有所貢獻。 / Next Generation Network,NGN, is a new form of internet concept of Triple play informational service integrated voice mail, data and video as the requirements of more wider bandwidth and high internet power increase. Meanwhile, The core of IP Multimedia Subsystem,IMS, NGN targets can lower operational cost to system suppliers. NGN emphasizes the spirit to combine Fixed Mobile Convergence,FMC, all IP network and Enhanced Quality of Service. The spirit makes the suppliers of informational service and system to think a new business model to make profits in NGN. The research of this thesis bases on NGN’s structure and features to analyze the trend of digital convergence in internet and succeeded business model. This essay adopts Case Study Research. By collecting sub data and relative document research figures out future image of NGN business model. Besides, it is interviewed with pertaining businesses to testify the reality of business model offered in this thesis. Owning to the scope of informational service business is unlimited, the thesis is chosen VoIP and IPTV as main targets to find out an appropriate and a profitable business model in this informational field. Furthermore, to business user, NGN can support industries to increase competitive ability and gain useful business information, decrease communicative cost and upgrade the performance of MIS

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