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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.
671

The Influence Of Argumentation Based Instruction Onsixth Grade Students

Oguz Cakir, Bahriye Zuhal 01 September 2011 (has links) (PDF)
The purpose of this study was to investigate the influence of argumentation based instruction on sixth grade students
672

Conceptual Quantity Modeling Of Single Span Highway Bridges By Regression, Neural Networks And Case Based Reasoning Methods

Asikgil, Mert 01 June 2012 (has links) (PDF)
Conceptual estimation techniques play an important role in determining the approximate costs of construction projects especially during feasibility stages. Moreover, pre-design estimates are also crucial for the contractors. With the help of the conceptual predictions companies can determine approximate project costs and can gain several advantages before tendering phase. The main objective of this thesis is to focus on modeling of quantities instead of costs and to develop quantity take-off models for pre-design cost estimation of bridge projects. Majority of the existing studies focus on modeling of costs for conceptual cost estimation. This study includes modeling of the quantity take off items in a specific single span highway bridge using three different techniques namely, linear regression, neural network and case based reasoning. During this study 40 single span highway bridge projects whose owner is Republic of Turkey General Directorate of Railways, Ports and Airports Constructions were investigated and models for each work item were developed. Then by integrating the quantity take off estimations with unit costs, total project costs were calculated. As a result by evaluating the prediction performance of the models, comparison of the methods was achieved. Results are discussed along with the advantages of the proposed method for conceptual cost estimation of bridge projects.
673

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).
674

Selecting Web Services by Problem Similarity

Yan, Shih-hua 11 February 2009 (has links)
The recent development of the service-oriented architecture (SOA) has provided an opportunity to apply this new technology to support model management. This is particularly critical when more and more decision models are delivered as web services. A web-services-based approach to model management is useful in providing effective decision support. When a decision model is implemented as a web service, it is called a model-based web service. In model management, selecting a proper model-based web service is an important issue. Most current research on selecting such web service relies on matching inputs and outputs of the model, which is oversimplified. The incorporation of more semantic knowledge may be necessary to make the selection of model-based web services more effective. In this research, we propose a new mechanism that represents the semantics associated with a problem and then use the similarity of semantic information between a new problem description and existing web services to find the most suitable web services for solving the new problem. The paper defines the concept of entity similarity, attribute similarity, and functional similarity for problem matching. The web service that has the highest similarity is chosen as a base for constructing the new web services. The identified mapping is converted into BPEL4WS codes for utilizing the web services. To verify the feasibility of the proposed method, a prototype system has been implemented in JAVA.
675

Conceptual design of miniature vegetation cutter for demining activities in difficult terrain – an evaluation : Intended for the Chouf Mountains, Lebanon

Sjölander, Emmily, Risén, Hanna January 2009 (has links)
<p>A conceptual design of a miniature vegetation cutter for use in minefields in southern Lebanon has been developed and the authors have evaluated its mechanical properties focusing on the stress in welded joints using the CAD software <em>Pro/Engineer Wildfire 4.0</em>. The conceptual design has been developed in the field in close cooperation with field staff from MAG Lebanon.</p><p>The requirements from the field specify that the cutter should have a cutting range of 80 cm, be equipped with adjustable covers, weigh less than 200 kg, be fitted to a commercial hydraulic excavator, and have the ability to cut vegetation, bushes and small trees including (olive) trees with a diameter up to 10 cm.</p><p>The miniature cutter is to be manufactured in the field and fitted to a commercial hydraulic ex­cava­tor (Caterpillar 301.6C). It consists of a rotor on which eight cutting blades, alternatively chains, are attached in a helix formation. The cutter is protected by adjustable covers. When in operation, the rotor spins at 750 revolutions per minute whereby the blades cut through the shrubs and bushes in the cutter’s path. The blades are mounted in a T-shape on arms, which are fastened to the rotor by a pin joint between two brackets (each) on the rotor. Blades and arms are to be welded together, as are the brackets to the rotor. These welded joints are the primary focus of the report. 3D CAD models have been created and analysed in <em>PTC Pro/Engineer Wildfire 4.0</em> to ascertain that the stress in the joints will not exceed the yield strength of the weld consumables, which should be 500 MPa. Ideally, the stress in the joints would be half the yield strength.</p><p>Type of bearings and a hydraulic motor have been selected for the cutter. Based on the specifica­tions of the hydraulic motor an approximation of the forces acting on the weld joints in the case of an accidental stop (e.g. collision with a rock) has been calculated, and entered into the CAD software. Also, an approximation of the size (diameter) of branches the cutter would be able to tear apart in the case of branches getting stuck has been calculated and shown to be about 14.6 mm. Based on this, it is estimated that the cutter should be used only in areas where the shrubbery is of 20-30 mm in diameter, maximum. Considering this, and the relative light weight of the cutter, it is not likely that the cutter will be able to cut through the larger olive trees as requested, but it is considered that the tool still could be a valuable asset for mine clearing in Lebanon. In order to cut through thicker trees, it would be necessary to increase the power supply to the cutting system as well as the sturdiness of the cutting parts. Finding the required power and technical solutions for this demands further research which does not fit within the time frame for this report.</p><p>A preliminary weight approximation shows that the cutter will weigh roughly 170 kg, which falls below the limit of 200 kg and leaving some room for the bearings to be added.</p><p>The results from the stress analyses show that the stress in the welded joints falls well below the yield limit of 500 MPa, but not below 250 MPa. Still, the stress in all the welded joints is shown to be less than 300 MPa or at 40 % of the limit, which may still be acceptable. The end user will have to decide whether this is an acceptable safety margin before manufacturing the cutter and if it is not, measures will need to be taken to reinforce the weld joints and try to minimise the stress concentration in them.</p>
676

Neuropsychology of Semantic Memory: Theories, Models, and Tests

Laurila, Linda January 2007 (has links)
<p>Semantic memory is part of the long-term memory system, and there are several theories concerning this type of memory. Some of these will be described in this essay. There are also several types of neuropsychological semantic memory deficits. For example, test results have shown that patients tend to have more difficulties naming living than nonliving things, and one probable explanation is that living things are more dependent on sensory than on functional features. Description of concrete concepts is a new test of semantic memory, in which cueing is used, both to capture the maximum performance of patients, and to give insight into the access versus storage problem. The theoretical ideas and empirical results relating to this new test will be described in detail. Furthermore, other tests of semantic memory that have been commonly used will also be briefly described. In conclusion semantic memory is a complex cognitive system that needs to be studied further.</p>
677

'Consider' and its Swedish equivalents in relation to machine translation

Andersson, Karin January 2007 (has links)
<p>This study describes the English verb ’consider’ and the characteristics of some of its senses. An investigation of this kind may be useful, since a machine translation program, SYSTRAN, has invariably translated ’consider’ with the Swedish verbs ’betrakta’ (Eng: ’view’, regard’) and ’anse’ (Eng: ’regard’). This handling of ’consider’ is not satisfactory in all contexts.</p><p>Since ’consider’ is a cogitative verb, it is fascinating to observe that both the theory of semantic primes and universals and conceptual semantics are concerned with cogitation in various ways. Anna Wierzbicka, who is one of the advocates of semantic primes and universals, argues that THINK should be considered as a semantic prime. Moreover, one of the prime issues of conceptual semantics is to describe how thoughts are constructed by virtue of e.g. linguistic components, perception and experience.</p><p>In order to define and clarify the distinctions between the different senses, we have taken advantage of the theory of mental spaces.</p><p>This thesis has been structured in accordance with the meanings that have been indicated in WordNet as to ’consider’. As a consequence, the senses that ’consider’ represents have been organized to form the subsequent groups: ’Observation’, ’Opinion’ together with its sub-group ’Likelihood’ and ’Cogitation’ followed by its sub-group ’Attention/Consideration’.</p><p>A concordance tool, http://www.nla.se/culler, provided us with 90 literary quotations that were collected in a corpus. Afterwards, these citations were distributed between the groups mentioned above and translated into Swedish by SYSTRAN.</p><p>Furthermore, the meanings as to ’consider’ have also been related to the senses, recorded by the FrameNet scholars. Here, ’consider’ is regarded as a verb of ’Cogitation’ and ’Categorization’.</p><p>When this study was accomplished, it could be inferred that certain senses are connected to specific syntactic constructions. In other cases, however, the distinctions between various meanings can only be explained by virtue of semantics.</p><p>To conclude, it appears to be likely that an implementation is facilitated if a specific syntactic construction can be tied to a particular sense. This may be the case concerning some meanings of ’consider’. Machine translation is presumably a much more laborious task, if one is solely governed by semantic conditions.</p>
678

Bücher kommen entgegen

Schneider, Ulrich Johannes 23 September 2009 (has links) (PDF)
In Buchausstellungen begegnen wir Texten, die auf Tonscherben, Papyrus, Pergament oder Papier geschrieben oder gedruckt sind. Die oft nicht sehr großen und nur ausnahmsweise farbigen Objekte werden uns in unterschiedlichen Zusammenhängen vorgeführt, je nach Ausstellungsthema. Kann man über Buchausstellungen und ihre Räume etwas sagen, auch unabhängig vom Thema einer Ausstellung? Die folgenden Überlegungen versuchen das, sowohl abstrakt wie konkret.
679

Collaborilla : An enhancement to the Conzilla concept browser for enabling collaboration

Ebner, Hannes January 2006 (has links)
<p>The research field Knowledge Management (KM) is about improving methods to structure and filter information. A concept browser makes it possible to navigate through complex information structures. Conzilla is such a concept browser. It is designed to present knowledge, to set concepts into relations to each other, and to make browsing through the resulting context-maps possible. Conzilla allows information and content being tied to concepts and concept-relations.</p><p>The collaboration facilities in Conzilla are limited. Basic elements such as a lookup mechanism and lifecycle information for information structures are missing. Before knowledge can be contributed, it is necessary to make sure that dependencies are fulfilled and the history of an edited object is obtained. This thesis is about providing these missing parts.</p><p>To be able to load a container, the information about the location of a component has to be held by a central registry. To resolve eventually existing dependencies, it is also necessary to register the components and its references. This thesis provides a design which eliminates the existing restrictions. The aim is to allow real collaboration through a remote services infrastructure, realized with Collaborilla. The theoretical background is discussed as well as a practical solution, including a prototype of a remote collaboration service.</p>
680

Better safe than sorry: : Applying philosophical methods to the debate on risk and the precautionary principle

Sandin, Per January 2004 (has links)
<p>The purpose of the present thesis is to apply philosophical methods to the ongoing debate of the precautionary principle, in order to illuminate this debate. The thesis consists of an Introduction and five papers. Paper I con-cerns an objection to the method of conceptual analysis, the Charge from Psychology. After a brief characterisation of conceptual analysis, I argue that the Charge from Psychology is misdirected. In Paper II, the method of conceptual analysis is applied to the concept of precaution which is ana-lysed in terms of precautionary actions. The purpose is explicatory. A definition involving three necessary and jointly sufficient conditions is proposed, and the implications of this analysis for the debate on the pre-cautionary principle are discussed. Paper III attempts to provide an ana-lytical apparatus which may be used for finding improved formulations of the precautionary principle. The approach is lexicographical. Several exist-ing and possible formulations of the precautionary principle are examined, and four common elements and a common structure of the precautionary principle are identified. It is suggested that the analytical apparatus pre-sented can be used in negotiations of the precautionary principle. Paper IV questions the soundness of some arguments against the precautionary prin-ciple. Five common arguments are discussed and rejected. In Paper V, two of these arguments are further discussed. I argue that an attempt at rejec-tion of the precautionary principle delivered by John Harris and Søren Holm is unwarranted, because their arguments against it are based on in-terpretations of the precautionary principle that ignore context. Paper VI deals with the idea of de minimis risk. After a discussion of the distinction between disregarding a risk and accepting it, I examine one way of deter-mining how small a risk ought to be in order to be disregarded, namely the use of natural risk levels as benchmarks. I argue that this approach fails, even if the distinction between what is natural and what is not natural can be upheld.</p>

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