TY - CHAP A1 - Robert-Nicoud, Yvan A1 - Raphael, Benny A1 - Smith, Ian F. C. T1 - Using entropy to maximize the usefulness of data collection N2 - This paper presents a generic methodology for measurement system configuration when the goal is to identify behaviour models that reasonably explain observations. For such tasks, the best measurement system provides maximum separation between candidate models. In this work, the degree of separation between models is measured using Shannon’s Entropy Function. The location and type of measurement devices are chosen such that the entropy of candidate models is greatest. This methodology is tested on a laboratory structure and, to demonstrate generality, an existing fresh water supply network in a city in Switzerland. In both cases, the methodology suggests an appropriate set of sensors for identifying the state of the system. KW - Mobile Computing KW - Funknetz KW - Entropie Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1177 ER - TY - THES A1 - Rickert, Jörg T1 - Zum Einfluss von Langzeitverzögerern auf der Basis von Phosphonsäure auf die Hydratation einzelner Klinkerphasen, Portlandzementklinker und Portlandzemente T1 - About the influence of long-term retarders on the basis of phosphonic acid on the hydration of several clinker phases, portland cement clinkers and portland cements N2 - Neben dem Schwerpunkt der Verflüssigung werden auch Zusatzmittel benötigt, die extrem lange Verarbeitbarkeitszeiten des Betons ermöglichen. Eine neue Wirkungsgruppe, durch die Verarbeitbarkeitszeiten von über 90 Stunden er-reicht werden können, sind Langzeitverzögerer (LVZ) auf der Basis von Phosphonsäure. In systematischen Versuchen wurden grundlegende Erkenntnisse über die Wirkungsmechanismen von LVZ auf die Hydratation gewonnen. Es hat sich gezeigt, dass die verzögernde Wirkung von LVZ auf die Bildung von schwer löslichem Calciumphosphonat zurückzuführen ist, welches die Partikeloberflächen žabdichtetœ. Vom Angebot an gelöstem Calcium hängt es ab, ob sich das žabdichtendeœ Calciumphosphonat direkt bildet oder ob durch den Calciumanspruch des LVZ eine kurzzeitig verstärkte Hydratation reaktiver Klin-kerphasen hervorgerufen wird. Sulfatoptimierte Zemente wiesen aufgrund der Anteile an Sulfatträger genüge! nd Calcium-Ionen für eine sofortige Bildung von Calciumphosphonat auf. In Verbindung mit der Bildung von primärem Ettringit bildet die Sulfatträgeroptimierung die Grundlage für die erwünschte Wirkungsweise des Zusatzmittels. N2 - In addition to the large group of plasticizing admixtures, such kind of admixtures are required which enable a very long time of workability of concrete. The workability of concrete over a period of more than 90 hours can be achieved by long-term retarders. This new type of admixture is based on phosphonic acid. By systematic investigations profound knowledge about the operative mechanisms of long-term retarders could be drawn. The retarding action is due to a formation of sparingly soluble calcium phosphonate which žseal upœ the particle surface. Whether the addition of long-term retarder leads to an immediate formation of calcium phosphonate or to a short termed acceleration of the hydration of reactive clinker phases depends on the supply of solved calcium. Because of the adjusted calcium sulphate content in cement the concentration of calcium is high enough for an immediate formation of sparingly soluble calcium! phosphonate. In combination with the formation of primary ettringite the calcium sulphate agent is the basis for the desired mode of action of the long-term retarder. KW - Beton KW - Recycling KW - Hydratation KW - Klinker KW - Betonzusatzmittel KW - Betonzusatzmittel KW - Langzeitverzögerer KW - Phosphonocarbonsäure (PBTC) KW - Wirkungsmechanismen KW - Zement KW - concrete admixture KW - long-term retarder KW - phosphonocarbon acid (PBTC) KW - operative mechanisms KW - cement Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20040211-232 ER - TY - CHAP A1 - Rickelt, Christian A1 - Reese, Stefanie T1 - A model adaptive and model reduction strategy combining system-theoretical methods and substructuring N2 - This paper focuses on a new three-level discretisation strategy which enables the transition between continuum/structural (I) and structural/black box modelling (II). The transition (I) is realised by means of a model adaptive concept based on an innovative finite element technology. For transition (II) we apply the truncated balanced realisation method (TBR). The latter represents an established system theoretical model reduction technique which is here combined with a novel substructure technique. The approach provides a modular concept to facilitate the computational analysis of complex structures. The final goal is to apply the strategy to life time estimation. KW - Adaptives System Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1516 ER - TY - THES A1 - Ressel, Oliver T1 - Entscheidungshilfen für die Planung von Anlagen zum naßmechanischen Recycling von Betonrestmassen T1 - Recycling of concrete wastes N2 - Trotz der weiten Verbreitung erfolgt die Planung der Restbetonrecyclinganlagen immer noch durch learnig-by-doing, da verfahrenstechnisches Grundlagenwissen nicht vorliegt. Wer an verantwortlicher Stelle die Investition in eine neue oder in die Verbesserung einer bestehenden Restbetonrecyclinganlage beurteilen soll, steht vor einer komplexen Entscheidung, die unter Berücksichtigung unterschiedlichster Kriterien getroffen werden muss. In der Praxis besteht hinsichtlich der Qualitätssicherung der Recyclingprodukte, der Ablagerungen der noch reaktiven Zementpartikel, der Bemessung der eingesetzten Maschinen, der praktikablen Handhabung hinsichtlich einiger Detailprobleme sowie der Anordnung der verfahrenstechnischen Komponenten in Bezug zur Geländeoberkante weitgehend Unklarheit. Das allgemeine Verlangen nach einer durchdachten Entscheidungshilfe und die Notwendigkeit, zu einem sachlich begründeten Urteil zu kommen, macht Entscheidungshilfen für die Planung von Restbetonrecyclinganlagen erforderlich. Insbesondere da Fehlentscheidungen nicht nur mit großem Aufwand rückgängig gemacht werden können. Hierfür wurden 18 maßgebliche Entscheidungskriterien entwickelt. Diese Entscheidungskriterien wurden im Rahmen der Nutzwertanalyse als Projektziele entwickelt. Die erarbeiteten Kriterien einteilen: - Kriterien zur Qualitätssicherung bei der Verwendung der Recyclingprodukte Für die Wiederverwendung der Recyclingprodukte Restwasser und Restbetonzu- schlag sind im technischen Regelwerk Verfahrensweisen vorgechrieben. Hinsichtlich der Prozesse bei der Wiederverwendung konnten deutliche Ver- besserungspotentiale aufgezeigt werden. Besonders die Anwendung von online- Dichtemessverfahren im Vergleich zur Aräometermessung verbessert die Len- kungsprozesse zur Qualitätssicherung. Aber auch die weitere Klassierung oder das getrennte Lagern und Dosieren des Restbetonzuschlags im Vergleich zu der im technischen Regelwerk vorgeschriebenen Verfahrensweise des volumetrischen Abschätzens bringt Verbesserungspotential. - Kriterien zur Minimierung von Ablagerungen Noch reaktive Zementpartikel kommen zeitweise permanent mit Anlagen- komponenten, Leitungen und Beckeninnenflächen der Recyclinganlage in Be- rührung. Ablagerungen von Zementpartikeln, die den Betrieb der Anlage be- hindern, verschlechtern oder sogar verhindern, sind unvermeidbar. Aller- dings kann, wie im Rahmen dieser Arbeit gezeigt wurde, eine Minimierung der Ablagerungen durch geeignete Maßnahmen herbeigeführt werden. Die Ablage- rungen im Suspensionsbeckenlassen sich durch den Zustand der homogenen Suspension sowie durch das Strömungsbild angepasste Formgebung minimieren. Durch die geeignete Gefällewahl und vor allem durch die korrekte Wahl der Pumpenart können die Ablagerungen in Leitungen minimiert werden. - Kriterien zur Bemessung der verfahrenstechnischen Apparate Die Auslegung der Recyclinganlage hinsichtlich der Auswaschleistung, der Rührerleistung und der Größe des Suspendierraumes erfolgt bisher anhand von praktischen Erfahrungswerten. In dieser Arbeit wurde für die Auswasch- leistung ein allgemeingültiges Berechnungsmodel hergeleitet. Darüber hinaus wurde gezeigt, dass die Rührerleistung für das Suspendieren von Restwasser berechnet werden kann. Die Größe des Suspendierraumes kann unter Be- rücksichtigung der zu- und abfließenden Materialströme berechnet werden. Das Trennverhalten des mechanischen Klassierers wurde im Rahmen einer Ver- suchsreihe mit folgenden Ergebnissen ermittelt: a. Die Klassierdurchsätze steigen mit größer werdendem Entleerdurchsatz. ufgrund der Pufferwirkung des mechanischen Klassierers, bei der die diskontinuierlich in den Aufgabetrichter gefüllte Restbetontrübe (Ent- leeren) in einem kontinuerlichen Prozess (Klassieren) durch den Trog gefördert wird, nähert sich der Klassierdurchsatz asymtotisch einem Grenzwert an. b. Das Masseausbringen rbz wird signifikant vom Klassierdurchsatz und weniger vom Entleerdurchsatz beeinflusst. c. Die Korngrößenverteilung des Restbetons, des Restbetonzuschlags und des Restwassers belegen anschaulich den erreichten Trenneffekt. d. Die Trennkorngröße steigt mit zunehmendem Klassierdurchsatz an. Diese Tendenz ist allerdings nur bei Betrachtung des "nassen" Klassier- durchsatzes signifikant erkennbar. Bei Betrachtung des "trockenen" Durchsatzes ergibt sich keine Abhängigkeit. Die Ursache hierfür ist, dass in den "nassen" Durchsatz Prozesse wie Trübeagitation und Feinkorn- konzentration indirekt eingehen. e. Der Fehlkornanteil < 125 µm im Restbetonzuschlag steigt ebenfalls mit "nassem" Klassiersatz an. f. Im Unterschied dazu bestehen für den Fehlkornanteil > 125 µm im Rest- wasser signifikante Abhängigkeiten zu Entleer- und Klassierdurchsätzen. Ursache ist der tote Fluss. - Kriterien zur Praktikabilität des Anlagenberiebes - Interdependenzen zwischen Anlagenkomponenten N2 - Recycling of concrete wastes KW - Restbeton KW - Rückbeton KW - Klassieren KW - Suspendieren KW - Concrete KW - Waste Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20040511-831 ER - TY - CHAP A1 - Ren, Aizhu A1 - Shi, Jianyong A1 - Xu, Yun T1 - Modeling of Buildings and Roads for Urban Applications based on 2D Digital Maps N2 - Three-dimensional models of urban objects play an important role in the urban applications such as urban planning, environmental concerning, or urban disaster mitigations. While the modeling of urban objects is time consuming and storage costing. This paper presents solutions for this. Buildings with regular shapes and plane roofs are constructed into computer models by identifying of graphic elements from the digital maps of urban area to get building base plane and building heights. Buildings with irregular shapes and non-plane roofs are constructed into computer models by employment of a specific system developed by the authors. Road objects and topologies are constructed into computer models by employment of specific algorithms. The solutions presented in this paper has been used in the development of urban disaster mitigation system for Shantou, China. KW - Architektur KW - Verteiltes System KW - Geoinformationssystem Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1791 ER - TY - CHAP A1 - Reinhardt, Jan A1 - Garrett, James H. A1 - Akinci, Burcu T1 - SiDaCoS: Product and Process Models on Construction Sites N2 - Site superintendents performing project management tasks on construction sites need to access project documents and need to collect information that they observe while inspecting the site. Often, information that is observed on a construction site needs to be integrated into electronic documents or project control systems. In the future, we expect integrated product and process models to be the medium for storing and handling construction project management information. Even though mobile computing devices today are already capable of storing and handling such integrated product and process data models, the user interaction with such large and complex models is difficult and not adequately addressed in the existing research. In this paper, we introduce a system that supports project management tasks on construction sites effectively and efficiently by making integrated product and process models accessible. In order to effectively and efficiently enter or access information, site superintendents need visual representations of the project data that are flexible with respect to the level of detail, the decomposition structure, and the type of visual representation. Based on this understanding of the information and data collection needs, we developed the navigational model framework and the application Site Data Collection System (SiDaCoS), which implements that framework. The navigational model framework allows site superintendents to create customized representations of information contained in a product and process model that correspond to their data access and data collection needs on site. KW - Mobile Computing KW - Funknetz KW - Baustelle KW - Controlling KW - data collection KW - construction management KW - product and process models KW - system KW - Work Face Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1156 ER - TY - CHAP A1 - Raue, Erich A1 - Weitzmann, Rüdiger T1 - Analysis and Design of Hybrid Structures using Optimization Strategies N2 - The paper gives a general overview and concerns with a specified set of computer-aided analysis modules for hybrid structures loaded by extreme excitations. All problems are solved by methods of linear, quadratic or nonlinear mathematical optimization, that leads to very effective and economic design solutions. All approaches are derived from general optimization problem that can be easily altered to conform to specific design tasks. Some advantages and possibilities of hybrid structural modeling (single or mixed model-supported) are discussed. The methods will be illustrated by an example structure and optimization schemes. KW - Konzipieren KW - Bauwerk KW - Optimierung Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1023 ER - TY - CHAP A1 - Portz, Norbert T1 - Was muss eine öffentliche Ausschreibung leisten? N2 - Voraussetzungen einer ordnungsgemäßen Ausschreibung, Beachtung des Vergaberechtssystems, Vergaberecht bei Privatisierungen, Abgrenzung zwischen VOL- und VOF-Verfahren, ordnungsgemäße Schwellenwertermittlung, Finanzierung und Planung, richtige Vergabeart, richtige Leistungs- und Aufgabenbeschreibung, ordnungsgemäße Wertung, Aufhebung der Ausschreibung, ordnungsgemäßer Vergabevermerk KW - Baubetriebslehre KW - Öffentlicher Auftrag / Vergabe KW - Deutschland / Vergabe- und Vertragsordnung für Bauleistungen KW - Ausschreibung Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-7175 ER - TY - CHAP A1 - Planker, Markus T1 - Die Aufsichtspflicht (und Klärungspflicht) des Architekten, Architekten- und Ingenieurhaftung, Berufshaftpflichtversicherungen N2 - Der Architektenvertrag als Werkvertrag (Konsequenzen: Haftung für den Werkerfolg, keine abschließende Bestimmung des vom Architekten geschuldeten Leistungsumfanges durch den Tätigkeitskatalog etwa von § 15 HOAI), vertragliche und außervertragliche Haftungstatbestände (vertragliche Ansprüche des Auftraggebers gegen den Architekten, Haftung gegenüber Dritten aufgrund des Architektenvertrages), typische Haftungsrisiken des Architekten, insbesondere im Kostenbereich sowie für Planungs- und Objektüberwachungsfehler (Haftung des Architekten für Überschreitung der Baukosten, Architektenhaftung bei Planungs- und Objektüberwachungsfehlern), Zulässigkeit der Vereinbarung von Haftungsbeschränkungen, Berufshaftpflichtversicherung für Architekten und Ingenieure KW - Baubetriebslehre KW - Haftung KW - Architektenrecht KW - Berufshaftung Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-7227 ER - TY - JOUR A1 - Pick, Tobias A1 - Heimsund, Bjoern-Ove A1 - Milbradt, Peter T1 - Development and Analysis of Sparse Matrix Concepts for Finite Element Approximation on general Cells N2 - In engineering and computing, the finite element approximation is one of the most well-known computational solution techniques. It is a great tool to find solutions for mechanic, fluid mechanic and ecological problems. Whoever works with the finite element method will need to solve a large system of linear equations. There are different ways to find a solution. One way is to use a matrix decomposition technique such as LU or QR. The other possibility is to use an iterative solution algorithm like Conjugate Gradients, Gauß-Seidel, Multigrid Methods, etc. This paper will focus on iterative solvers and the needed storage techniques... KW - Finite-Elemente-Methode KW - Physikalisches Verfahren KW - Bandmatrix Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-2500 ER - TY - CHAP A1 - Petzold, Frank A1 - Donath, Dirk T1 - The building as a container of information : the starting point for project development and design formulation N2 - For planning in existing built contexts, the building survey is the starting point for initial planning proposals, for the diagnosis and documentation of building damages, for the creation of objectives catalogues, for the detailed design of renovation and conversion measures and for ensuring fulfilment of building legislation, particularly by change of use and refitting. An examination of currently available IT-tools shows insufficient support for planning within existing contexts, most notably a deficit with regard to information capture and administration. This paper discusses the concept for a modular surveying system (basic concept, separation of geometry from semantic data, and separation into sub-systems) and the prototypical realisation of a system for the complete support of the entire building surveying process for existing buildings. The project aims to contribute to the development of a planning system for existing buildings. ... KW - Architektur KW - Verteiltes System KW - Lebenszyklus KW - Bauwerk Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1848 ER - TY - CHAP A1 - Petzold, Frank A1 - Bartels, Heiko A1 - Donath, Dirk T1 - New techniques in Building Surveying N2 - Building activities in the construction industry in Germany increasingly concentrate on building measures in or involving the existing built environment. Before planning can begin, buildings must be surveyed in whole or in part with the surveying of geometric data playing a dominant role. The geometric survey is typically undertaken using geodetic or photogrammetric measuring techniques and equipment that have been adapted for use in building surveying. Accordingly appropriate technical knowledge is required in order to be able to operate them as well as a considerable financial investment. Such equipment and surveying methods are usually adaptations from other disciplines. The paper discusses and presents approaches to developing “new” equipment for building surveying, devised with the needs of building surveying in mind – redesigns or new designs for surveying tools. The designs are the result of an inter-disciplinary project between the Faculty of Architecture and the Faculty of Product Design at the Bauhaus Universität Weimar. KW - Architektur KW - Verteiltes System KW - Bausubstanz Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1803 ER - TY - CHAP A1 - Petersen, Michael A1 - Seewald, Gerrit T1 - Establishing of fundamentals in building projects using web services N2 - During the establishing of fundamentals in a building project a huge amount of influence factors and boundary conditions have to be investigated in order to provide the prerequisites for further planning processes. These investigative tasks are often related with a great effort concerning time and money, because there are no standardized workflows and interfaces which provide an efficient access to the necessary information related to a specific construction site. Within the fundamental investigation human and natural circumstances have to be taken into account. Thus, in this project two examples have been chosen in order to demonstrate the holistic approach for an integration and provision of georeferenced information. The developed internet-site http://www.grundlagenermittlung.de has been designed to support architects and civil engineers in early planning phases of a building project efficiently. It offers web-based services based on dynamic interfaces for a flexible search and collection of information concerning the building site. Therefore, a central Metadatabase-Server for Description, Discovery and Integration has been established which enables a registration of georeferenced services and the redirection of incoming requests to other, distributed data pools. Using this Yellow-Page concept in combination with the underlying meta-data based on the ISO 19115 standard an efficient investigation of geographical and environmental information becomes possible. KW - Bauwerk KW - Datenmanagement KW - Internet Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1273 ER - TY - CHAP A1 - Petersen, Michael A1 - Diaz, Joaquin T1 - Integrated planning of buildings based on computer models in project communication systems N2 - The increasing demands in building and civil engineering – with regard to the growing amount of legal requirements and the needs of a flexible usage of the building - requires an optimisation of all processes during the planning and construction phases. This aim can be only reached by transferring of innovative information and communication technologies in the field of cooperation of all partners in a building project. In this article the enhancement of the existing planning processes based on an improved information management is introduced. Since the late 90ies the availability of hardware and software infrastructures for a networkbased cooperation, e.g. email, in small and middle-sized companies increased the problems of an unstructured communication in the planning and construction processes. These problems have not been solved by the usage of the upcoming project communication systems either, which are often used as a simple medium for data transfer. Because of the easy way of distributing documents to all planning partners a huge amount of files and subsequent versions can be stored so that the planners often have to scope with an information overflow. The underlying hierarchical structures based on simple files stored in tree views are not sufficient for an adequate representation of the different specific views of the planners and the management of relationships between the three information domains building structure, costs and time schedules. .. KW - Architektur KW - Verteiltes System KW - Integrierte Planung Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1762 ER - TY - CHAP A1 - Perevalova, Julia A1 - Pahl, Peter Jan T1 - Structural and Functional Dependence of Objects in Data Bases N2 - Let the information of a civil engineering application be decomposed into objects of a given set of classes. Then the set of objects forms the data base of the application. The objects contain attributes and methods. Properties of the objects are stored in the attributes. Algorithms which the objects perform are implemented in the methods of the objects. If objects are modified by a user, the consistency of data in the base is destroyed. The data base must be modified in an update to restore its consistency. The sequence of the update operations is not arbitrary, but is governed by dependence between the objects. The situation can be described mathematically with graph theory. The available algorithms for the determination of the update sequence are not suitable when the data base is large. A new update algorithm for large data bases has been developed and is presented in this paper. KW - Baubetrieb KW - Computerunterstütztes Verfahren KW - Objektorientierung KW - Datenbank Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1683 ER - TY - CHAP A1 - Peng, Jun A1 - Law, Kincho A1 - Lau, Gloria T1 - Internet-Enabled Software Model for Nonlinear Structural Analysis and Simulations N2 - This paper describes an Internet-enabled software model that could facilitate the development and utilization of nonlinear structural analysis programs. The software model allows users easy access to the analysis core program and the analysis results by using a web-browser or other application programs. In addition, new and legacy codes can be incorporated as distributed services and be integrated with the software framework from disparate sites. A distributed project management system, taking advantages of Internet and database technologies, is implemented to store and manage model information and simulation results. Nonlinear dynamic analysis and simulations of a bridge structure is performed to illustrate the facilities of the Internet-enabled software model. KW - Konzipieren KW - Bauwerk KW - Verteiltes System KW - Internet Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1057 ER - TY - CHAP A1 - Pavlov, Alexander T1 - Data Transfer and Objects Recognition in Building Design N2 - The problem of data interoperability is now very important. The formal description of construction systems and objects must base upon the modeling for the description of construction data domain. The XML-language was selected as a basis of a universal data format, ensuring natural hierarchy of objects, flexibility, good layout and expandability. The language, developed by the author, is called Building Object Description Extensible Markup Language (bodXML). The types of all objects used by data transfer should be definite beforehand with existing methods of programming. It limits the possibilities of IT in application of new types. But the recipient software must recognize the building objects even if the kind of object is unknown at the outset. The author offers a set of main topological and geometric properties being sufficient for recognition of main three-dimensional building constructions with flat edges. The tests of artificial neuron network have shown that the recognition of a kind of the constructions represented as a set of indicated parameters happens enough confidently. KW - Bauwerk KW - Datenmanagement KW - Datenaustausch Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1265 ER - TY - THES A1 - Pastohr, Henry T1 - Thermodynamische Modellierung eines Aufwindkraftwerkes T1 - Thermodynamical modelling of an upwind power plant N2 - Die Energieversorgung auf der Erde wird zukünftig zu einem Problem. Bedingt ist dies durch eine fortschreitende Verknappung der natürlichen Ressourcen, wie Kohle, Gas und Öl sowie einer Zunahme der CO2-Konzentration und anderer Schadstoffe in der Atmosphäre. Regenerative Energiequellen müssen genutzt werden, um den steigenden Energiebedarf zu sichern. Eine interessante Möglichkeit zur Nutzung der Solarenergie stellt das Aufwindkraftwerk dar. Das Aufwindkraftwerk besteht aus einem Kamin, um den ein Glasdachkollektor auf dem Erdboden angeordnet ist. Am Fuße des Kamins befinden sich Turbinen und Generatoren. Die einfallende Solarenergie wird hauptsächlich über die Wechselwirkung mit dem Erdreich in thermische Energie, in kinetische Energie, in Rotationsenergie und in elektrische Energie umgewandelt. Das Ziel der Arbeit bestand in der physikalisch-mathematischen Modellierung, der genaueren Erkennung des Wirkprinzips und der Diskussion der Anlagenparameter Leistung und Wirkungsgrad. Im Rahmen dieser Aufgabe wurden dazu stationäre und instationäre Computational Fluid Dynamic (CFD) Modelle und stationäre und instationäre vereinfachte Modelle entwickelt, diskutiert und miteinander verglichen. Grundlegend neue Erkenntnisse wurden bei den Verläufen der Temperaturen im Kollektor, insbesondere der Erdoberflächentemperatur erreicht. Parameteranpassungen im Wärmeübergangsmodell und Widerstandsmodell führten für vier ausgewählte, stationäre Sonnenenergien auf eine gute Übereinstimmung zwischen den Ergebnissen (Temperaturhub, Druckentnahme, Leistung und Wirkungsgrad) des stationären, hybriden Modells und des stationären CFD-Modells. Weiterhin stimmen die lokalen Größen Wärmeübergangskoeffizient, Erdoberflächentemperatur, Lufttemperatur und Glasdachtemperatur gut zwischen den Modellen überein. Mit dem CFD Modell wurden der Prototyp und 3 Großkraftwerke berechnet. Mit dem entwickelten instationären FDM-Modell wurden erstmalig numerische Langzeitsimulationen (1 Jahr) durchgeführt. Zur Überprüfung des Modells wurden die Ergebnisse mit Messwerten aus Manzanares verglichen, wobei eine gute Übereinstimmung erreicht werden konnte. Das Verständnis für die stattfindenden thermodynamischen und strömungsmechanischen Prozesse in einem Aufwindkraftwerk konnte durch die Arbeit maßgeblich verbessert werden. N2 - The energy supply on our earth will become a problem in future. This is conditional by a shortage of the natural source, like coal, gas and oil, as well as an increase in the concentration of gasous CO2 in the atmosphere. Regenerative energy sources must be used more increasingly to saveguard the increasing energy consumption. Upwind power plants represent an interesting possibility for the use of solar energy. The upwind power plant consist of an collector, an chimney and one ore several turbines. The collector heats the air by the interaction with the ground. The glass reflects the infrared radiation of the ground. The Chimney provides a large density difference between the collector exit and the atmosphere. The goal of this work was the mathematical und physical modelling of the thermodynamics in and around an upwind power plant. Steady and unsteady CFD models and steady and unsteady simplified models were developed and compared. Basically new knowledge was reached at the courses of the temperatures in the collector. A very good agreement between the results of the steady hybrid model and the steady CFD model (temperature difference of the collector, pressure at the turbine, power and degree of effectiveness) could be found for four solar energies. Furthermore, the local values of heat-transfer coefficient, soil temperature, temperature of the fluid and the temperature of the glass roof compare very well beetwen the models. The prototyp manzanares and three large power plants were solved with the developed CFD model. Numeric long time simulations (1 year) were carried out for the first time with the developed unsteady Finite-Difference-Model. The model was compared with results of the project Manzanares. A good agreement was found. The knowledge of the thermodynamical und fluid dynamical processes in an upwind power plant were improved substantial by this work. KW - Aufwindkraftwerk KW - Numerische Strömungsmechanik KW - Mathematisches Modell KW - Thermodynamik KW - Sonnenenergie KW - Sonnenkollektor KW - upwind power plant KW - CFD KW - mathematical modelling KW - thermodynamics KW - solar energy Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20040803-867 ER - TY - CHAP A1 - Parmee, Ian A1 - Abraham, Johnson T1 - User-centric Evolutionary Design Systems - the Visualisation of Emerging Multi-Objective Design Information N2 - The paper describes further developments of the interactive evolutionary design concept relating to the emergence of mutually inclusive regions of high performance design solutions. These solutions are generated from cluster-oriented genetic algorithm (COGAs) output and relate to a number of objectives introduced during the preliminary design of military airframes. The data-mining of multi-objective COGA (moCOGA) output further defines these regions through the application of clustering algorithms, data reduction and variable attribute relevance analyses. A number of visual representations of the COGA output projected onto both variable and objective space are presented. The multi-objective output of the COGA is compared to output from a Strength Pareto Evolutionary Algorithm (SPEA-II) to illustrate the manner in which moCOGAs can generate good approximations to Pareto frontiers. KW - Konzipieren KW - Bauwerk KW - Künstliche Intelligenz Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1094 ER - TY - CHAP A1 - Palm, Johan T1 - Integrated Engineering Workflow focused on the Structural Engineering in the Industrial Environment N2 - The engineering and construction industry has been slow to exploit the full potential of information technology. The industry is highly fragmented, price sensitive, risk-adverse, and profit margins are small. Each project is unique with a small amount of technological innovation opportunities to capitalise on from one project to the next. Technological innovations that have been taking place are just simulating the old traditional paper workflow. Engineering information in digital form is being conveyed using traditional paper representations, which have to be interpreted by humans before the information can be used in other applications, thereby creating ‘islands of information’. It can be seen that poorly implemented IT strategies are duplicating paperwork, rather than reducing or eliminating it (Crowley et al., 2000). This paper will introduce the Integrated Engineering Workflow (IEW) concept to re-organise a structural discipline working on multi-disciplinary projects so as to maximise the advantages offered by new information technology. KW - Baubetrieb KW - Computerunterstütztes Verfahren KW - Prozessmanagement KW - Ingenieurbau Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-1625 ER -