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... WITHOUT RIGHT ANGLE.
(2006)
Currently sculptural design is one of the most discussed themes in architecture. Due to their light weight, easy transportation and assembly, as well as an almost unlimited structural variety, parameterised spatial structures are excellently suited for constructive realisation of free formed claddings. They subdivide the continuous surface into a structure of small sized nodes, straight members and plane glass panels. Thus they provide an opportunity to realise arbitrary double-curved claddings with a high degree of transparency, using industrial semi-finished products (steel sections, flat glass). Digital design strategies and a huge number of similar looking but in detail unique structural members demand a continuous digital project handling. Within a research project, named MYLOMESH, a free-formed spatial structure was designed, constructed, fabricated and assembled. All required steps were carried out based on digital data. Different digital connections (scripts) between varying software tools, which are usually not used in the planning process of buildings, were created. They allow a completely digital workflow. The project, its design, meshing, constructive detailing and the above-mentioned scripts are described in this paper.
Radikale Pädagogik richtet ihre Aufmerksamkeit sowohl auf die alltäglichen Techniken pädagogischer Praxis – Techniken zur Aktivierung eines Begegnungsraumes, Techniken, sich um die Arbeit und einander zu kümmern, Techniken des kulturübergreifenden Zuhörens, Techniken, sich dem Mehr-als zuzuwenden – als auch auf Techniken zum »Überschreiten der Schwelle«. Das Überschreiten der Schwelle hängt mit der Art und Weise der Anpassung (accommodation) zusammen, die es ermöglicht, das Lernen in all seinen Erscheinungsformen wertzuschätzen.
Beiträge zur 2. Fachtagung „Sicherheit auf Baustellen“ am Dienstag, dem 20. März 2001 in Weimar an der Fakultät Bauingenieurwesen, Professur Baubetrieb und Bauverfahren der Bauhaus-Universität Weimar. Der Tagungsband enthält einen Spezialteil „Qualität und Sicherheit auf Baustellen und im Schweißbetrieb“ anlässlich des Ausscheidens von Herrn Prof. Dr.-Ing. habil. Karl-Dieter Röbenack aus dem aktiven Berufsleben.
Container sind nicht nur das bei weitem wichtigste Transportmittel für die allermeisten Waren, mit denen wir tagtäglich zu tun haben. Container sind, vielleicht wegen ihrer schlichten, klaren Ausdruckskraft, zu dem Symbol der Globalisierung geworden und vieler Phänomene, die man mit dieser Entwicklung in Zusammenhang bringt. Dabei handelt es sich um ein durch und durch ambivalentes Symbol. Container stehen genauso für die beeindruckende Dynamik des modernen Kapitalismus und den ihm trotz aller Krisen zugrunde liegenden Optimismus wie für die Ängste und Einwände dagegen; gegen die Indifferenz eines rein auf Optimierung ausgelegten logistischen Organisationshandelns und gegen die zwangsweise Annäherung und Angleichung ehedem entfernter Weltgegenden durch die exponentielle Vermehrung der Transport- und Kommunikationsvorgänge. Der Schwerpunkt der Arbeit liegt im 20. Jahrhundert. Sie untersucht die (Vor)Geschichte und Theorie des Containers als moderner Kulturtechnik und zentralem Bestandteil eines weltumspannenden logistischen Systems. Und sie zeigt ihn als Element eines Denkens und Organisationshandelns in modularen, beweglichen Raumeinheiten, das sich auch auf viele andere Bereiche außerhalb des Warentransports übertragen lässt. Dafür beschreibt und analysiert sie "Containersituationen" in so unterschiedlichen Feldern wie Handel und Transport, Architektur, Wissenschaften, Kunst und den sozialen Realitäten von Migranten und Seeleuten.
30. Forum Bauinformatik
(2018)
Die Bauhaus-Universität Weimar ist seit langer Zeit mit dem Forum Bauinformatik eng verbunden. So wurde die Veranstaltung 1989 hier durch den Arbeitskreis Bauinformatik ins Leben gerufen und auch das 10. und 18. Forum Bauinformatik (1998 bzw. 2006) fand in Weimar statt. In diesem Jahr freuen wir uns daher besonders, das 30. Jubiläum an der Bauhaus-Universität Weimar ausrichten zu dürfen und viele interessierte Wissenschaftler und Wissenschaftlerinnen aus dem Bereich der Bauinformatik in Weimar willkommen zu heißen.
Das Forum Bauinformatik hat sich längst zu einem festen Bestandteil der Bauinformatik im deutschsprachigen Raum entwickelt. Dabei steht es traditionsgemäß unter dem Motto „von jungen Forschenden für junge Forschende“, wodurch insbesondere Nachwuchswissenschaftlerinnen und ‑wissenschaftlern die Möglichkeit geboten wird, ihre Forschungsarbeiten zu präsentieren, Problemstellungen fachspezifisch zu diskutieren und sich über den neuesten Stand der Forschung zu informieren. Zudem wird eine ausgezeichnete Gelegenheit geboten, in die wissenschaftliche Gemeinschaft im Bereich der Bauinformatik einzusteigen und Kontakte mit anderen Forschenden zu knüpfen.
In diesem Jahr erhielten wir 49 interessante und qualitativ hochwertige Beiträge vor allem in den Themenbereichen Simulation, Modellierung, Informationsverwaltung, Geoinformatik, Structural Health Monitoring, Visualisierung, Verkehrssimulation und Optimierung. Dafür möchten wir uns ganz besonders bei allen Autoren, Co-Autoren und Reviewern bedanken, die durch ihr Engagement das diesjährige Forum Bauinformatik erst möglich gemacht haben. Wir danken zudem Professor Große und Professor Díaz für die Unterstützung bei der Auswahl der Beiträge für die Best Paper Awards.
Ein herzliches Dankeschön geht an die Kollegen an der Professur Informatik im Bauwesen der Bauhaus-Universität Weimar für die organisatorische, technische und beratende Unterstützung während der Planung der Veranstaltung.
Multi-user projection systems provide a coherent 3D interaction space for multiple co-located users that facilitates mutual awareness, full-body interaction, and the coordination of activities. The users perceive the shared scene from their respective viewpoints and can directly interact with the 3D content.
This thesis reports on novel interaction patterns for collaborative 3D interaction for local and distributed user groups based on such multi-user projection environments. A particular focus of our developments lies in the provision of multiple independent interaction territories in our workspaces and their tight integration into collaborative workflows. The motivation for such multi-focus workspaces is grounded in research on social cooperation patterns, specifically in the requirement for supporting phases of loose and tight collaboration and the emergence of dedicated orking territories for private usage and public exchange. We realized independent interaction territories in the form of handheld virtual viewing windows and multiple co-located hardware displays in a joint workspace. They provide independent views of a shared virtual environment and serve as access points for the exploration and manipulation of the 3D content. Their tight integration into our workspace supports fluent transitions between individual work and joint user engagement. The different affordances of various displays in an exemplary workspace consisting of a large 3D wall, a 3D tabletop, and handheld virtual viewing windows, promote different usage scenarios, for instance for views from an egocentric perspective, miniature scene representations, close-up views, or storage and transfer areas. This work shows that this versatile workspace can make the cooperation of multiple people in joint tasks more effective, e.g. by parallelizing activities, distributing subtasks, and providing mutual support.
In order to create, manage, and share virtual viewing windows, this thesis presents the interaction technique of Photoportals, a tangible interface based on the metaphor of digital photography. They serve as configurable viewing territories and enable the individual examination of scene details as well as the immediate sharing of the prepared views. Photoportals are specifically designed to complement other interface facets and provide extended functionality for scene navigation, object manipulation, and for the creation of temporal recordings of activities in the virtual scene.
A further objective of this work is the realization of a coherent interaction space for direct 3D input across the independent interaction territories in multi-display setups. This requires the simultaneous consideration of user input in several potential interaction windows as well as configurable disambiguation schemes for the implicit selection of distinct interaction contexts. We generalized the required implementation structures into a high-level software pattern and demonstrated its versatility by means of various multi-context 3D interaction tools.
Additionally, this work tackles specific problems related to group navigation in multiuser projection systems. Joint navigation of a collocated group of users can lead to unintentional collisions when passing narrow scene sections. In this context, we suggest various solutions that prevent individual collisions during group navigation and discuss their effect on the perceived integrity of the travel group and the 3D scene. For collaboration scenarios involving distributed user groups, we furthermore explored different configurations for joint and individual travel.
Last but not least, this thesis provides detailed information and implementation templates for the realization of the proposed interaction techniques and collaborative workspaces in scenegraph-based VR systems. These contributions to the abstraction of specific interaction patterns, such as group navigation and multi-window interaction, facilitate their reuse in other virtual reality systems and their adaptation to further collaborative scenarios.
Seit mehreren Jahren wird im Fachbereich Gestaltung, Studiengang Innenarchitektur 3D-Computergrafik und -animation in Lehrveranstaltungen ausgebildet und in Projekt- und Diplomarbeiten als Darstellungsmedium angewandt. Eine besondere Herausforderung stellen dabei die 3D-Visualisierungen von historischen Gebäuden dar. Mit den beiden nachfolgenden Beispielen soll der Einsatz und die curricularen Verknüpfung der CA-Technologie mit Studienarbeiten und Projekten zum Thema >Denkmalpflege< aufgezeigt werden. Rekonstruktion und Visualisierung des ehemaligen >Jagdschlosses Platte< bei Wiesbaden. Mit Unterstützung einer Kunsthistorikerin wurde in einer Studienarbeit das im Krieg zerstörte ehemalige Jagdschloß im Computer nachgebildet. Neben der Darstellung des Gebäudeäußeren und des zentralen Innenbereiches wurde eine Animation über die Triangulierung der klassizistischen Geometrie erstellt. Umnutzung historischer Bausubstanz am Beispiel der ehemaligen Klostersanlage >Schiffenberg< bei Gießen. Im Rahmen einer Projektarbeit wurden mehrer Konzepte entwickelt, Entwürfe erstellt und mittels Computeranimationen öffentlich präsentiert. In Kooperation mit dem Studiengang Fernsehtechnik (FH-Wiesbaden) wurde von zwei Studenten eine Videodokumentation über den gesamten Projektverlauf erstellt. Neben dem Aufzeigen der Arbeitsprozesse und dem Vorstellen des Lehrkonzeptes für die curriculare Einbindung der CA-Technologie werden aktuelle Studienergebnisse anhand von Videoprojektionen vorgestellt.
In classical complex function theory the geometric mapping property of conformality is closely linked with complex differentiability. In contrast to the planar case, in higher dimensions the set of conformal mappings is only the set of Möbius transformations. Unfortunately, the theory of generalized holomorphic functions (by historical reasons they are called monogenic functions) developed on the basis of Clifford algebras does not cover the set of Möbius transformations in higher dimensions, since Möbius transformations are not monogenic. But on the other side, monogenic functions are hypercomplex differentiable functions and the question arises if from this point of view they can still play a special role for other types of 3D-mappings, for instance, for quasi-conformal ones. On the occasion of the 16th IKM 3D-mapping methods based on the application of Bergman's reproducing kernel approach (BKM) have been discussed. Almost all authors working before that with BKM in the Clifford setting were only concerned with the general algebraic and functional analytic background which allows the explicit determination of the kernel in special situations. The main goal of the abovementioned contribution was the numerical experiment by using a Maple software specially developed for that purpose. Since BKM is only one of a great variety of concrete numerical methods developed for mapping problems, our goal is to present a complete different from BKM approach to 3D-mappings. In fact, it is an extension of ideas of L. V. Kantorovich to the 3-dimensional case by using reduced quaternions and some suitable series of powers of a small parameter. Whereas until now in the Clifford case of BKM the recovering of the mapping function itself and its relation to the monogenic kernel function is still an open problem, this approach avoids such difficulties and leads to an approximation by monogenic polynomials depending on that small parameter.
Das FEM-Programmsystem „SYSWELD“ kommt für die Berechnung des Temperaturfeldes bei einer Laserstrahlschweißung zum Einsatz. Insbesondere sollen der Einfluss des Energieeintrages und die damit verbundene Gefügeumwandlung eines Feinkornbaustahles untersucht und Aussagen zur notwendigen Modellierungsgenauigkeit der Nahtgeometrie bzw. Netzverfeinerung getroffen werden. Im Einzelnen sind folgende Teilaufgaben zu lösen: - ausführliche Literaturrecherche zur numerischen Analyse von Schweißverbindungen insbesondere zu temperaturabhängigen Materialeigenschaften von Feinkornbaustählen, - Darstellung der Wärmequelle für das Laserstrahlschweißen, - Erprobung unterschiedlicher Netzvarianten für die FE-Analyse von instationären Temperaturfeldern, - Untersuchung zur Modellierungsgenauigkeit der Nahtgeometrie, - Parameterstudien zum Einfluss der Materialkennwerte und Gefügekinetik auf das Temperaturfeld sowie das Gefüge.
Wissenschaftliches Kolloquium vom 27. bis 30. Juni 1989 in Weimar an der Hochschule für Architektur und Bauwesen zum Thema: ‚Produktivkraftentwicklung und Umweltgestaltung. Sozialer und wissenschaftlich-technischer Fortschritt in ihren Auswirkungen auf Architektur und industrielle Formgestaltung in unserer Zeit. Zum 100. Geburtstag von Hannes Meyer'
Jubiläumsbroschüre zum Tag des Baubetriebs >Prozesssteuerung-Projektleitung-Dienstleistung< am Freitag, dem 7. Juli 2000 in Weimar. Geleitwort des Rektors der Bauhaus-Universität Weimar 45 Jahre technologische Lehre und Forschung in Weimar Bauen im Jahr 2020 – Wohin verändert sich Baubetrieb? Statistische Übersichten
Die aktuelle demografische Entwicklung bedingt offensichtlich auch Arbeiten in rauer Umgebung bis zur Rente mit 67, auch auf dem Bau. Das Thema liegt scheinbar nur am Rande des Baubetriebswesens. Doch obwohl es sozialpolitisch determiniert ist, hat es sehr konkret mit Gesundheitsschutz, Arbeitsschutz und Arbeitsgestaltung zu tun. Die fünfte Fachtagung 'Sicherheit auf Baustellen' stellt sich der Diskussion, wie das Rentenalter gesund erreichbar ist, was alle am Arbeitsschutz Beteiligten schon heute und auch in Zukunft dafür tun können, und hinterfragt kritisch, wie realistisch diese pauschale Forderung nach Arbeit bis 67 ist. Forderungen nach schlankeren Strukturen im Staat und das Streben nach Deregulierung haben auch zu Veränderungen in der Arbeitsschutzverwaltung des Freistaates Thüringen geführt, über die das Forum informiert.
50 Jahre Dissertationen an der Hochschule für Architektur und Bauwesen und der Bauhaus-Universität
(2005)
Diese Veröffentlichung dokumentiert über einen Zeitraum von 50 Jahren die an unserer Hochschule entstandenen Dissertationen, deren Zahl sich auf 1100 beläuft. Damit werden ein wichtiger Teil der Hochschulgeschichte Weimars und zugleich ein Teil der Hochschulgeschichte der DDR aufgearbeitet. Die Bibliographie liefert Bausteine für eine Geschichte der Disziplinen und Fakultäten an der Weimarer Hochschule und darüber hinaus für eine Sozialgeschichte der Wissenschaftler in Thüringen. So hat z. B. eine Vielzahl der heute in leitender Stellung an der Universität Tätigen – sowohl Professoren als auch Mitarbeiter der Universitätsverwaltung – in Weimar promoviert. Das lässt sich auch ausdehnen auf Personen in führenden wissenschaftlichen, politischen oder wirtschaftlichen Positionen in der Region oder im Ort. Hier könnte die vorliegende Bibliographie Anstoß für weitere Forschungen geben.
Diese Veröffentlichung dokumentiert über einen Zeitraum von 50 Jahren die an unserer Hochschule entstandenen Dissertationen, deren Zahl sich auf 1100 beläuft. Damit werden ein wichtiger Teil der Hochschulgeschichte Weimars und zugleich ein Teil der Hochschulgeschichte der DDR aufgearbeitet. Die Bibliographie liefert Bausteine für eine Geschichte der Disziplinen und Fakultäten an der Weimarer Hochschule und darüber hinaus für eine Sozialgeschichte der Wissenschaftler in Thüringen. So hat z. B. eine Vielzahl der heute in leitender Stellung an der Universität Tätigen – sowohl Professoren als auch Mitarbeiter der Universitätsverwaltung – in Weimar promoviert. Das lässt sich auch ausdehnen auf Personen in führenden wissenschaftlichen, politischen oder wirtschaftlichen Positionen in der Region oder im Ort. Hier könnte die vorliegende Bibliographie Anstoß für weitere Forschungen geben.
Recent years have seen a gradual shift in focus of international policies from a national and regional perspective to that of cities, a shift which is closely related to the rapid urbanization of developing countries. As revealed in the 2011 Revision of the World Urbanization Prospects published by the United Nations, 51% of the global population (approximately 3.6 billion people) lives in cities. The report predicts that by 2050, the world’s urban population will increase by 2.3 billion, making up 68% of the population. The growth of urbanization in the next few decades is expected to primarily come from developing countries, one third of which will be in China and India.
With rapid urbanization and the ongoing growth of mega cities, cities must become increasingly resilient and intelligent to cope with numerous challenges and crises like droughts and floods arising from extreme climate, destruction brought by severe natural disasters, and aggregated social contradictions resulting from economic crises. All cities face the urban development dynamics and uncertainties arising from these problems. Under such circumstances, cities are considered the critical path from crisis to prosperity, so scholars and organizations have proposed the construction of “resilient cities.” On the one hand, this theory emphasizes cities’ defenses and buffering capacity against disasters, crises and uncertainties, as well as recovery after destruction; on the other hand, it highlights the learning capacity of urban systems, identification of opportunities amid challenges, and maintenance of development vitality. Some scholars even believe that urban resilience is a powerful supplement to sustainable development. Hence, resilience assessment has become the latest and most important perspective for evaluating the development and crisis defense capacity of cities.
Rather than a general abstract concept, urban resilience is a comprehensive measurement of a city’s level of development. The dynamic development of problems is reflected through quantitative indicators and appraisal systems not only from the perspective of academic research, but also governmental policy, so as to scientifically guide development, and measure and compare cities’ development levels. Although international scholars have proposed
quantitative methods for urban resilience assessment, they are however insufficiently systematic and regionally adaptive for China’s current urban development needs. On the basis of comparative study on European and North American resilient city theories, therefore, this paper puts forwards a theoretical framework for resilient city systems consistent with China’s national conditions in light of economic development pressure, natural resource depletion, pollution, and other salient development crises in China. The key factors influencing urban resilience are taken into full consideration; expert appraisal is conducted based on the Delphi Method and the analytic hierarchy process (AHP) to design an extensible and updatable resilient city evaluation system which is sufficiently systematic, geographically adaptable, and sustainable for China’s current urban development needs. Finally, Changsha is taken as the main case for empirical study on comprehensive evaluation of similar cities in Central China to improve the indicator system.
Paper-based data acquisition and manual transfer between incompatible software or data formats during inspections of bridges, as done currently, are time-consuming, error-prone, cumbersome, and lead to information loss. A fully digitized workflow using open data formats would reduce data loss, efforts, and the costs of future inspections. On the one hand, existing studies proposed methods to automatize data acquisition and visualization for inspections. These studies lack an open standard to make the gathered data available for other processes. On the other hand, several studies discuss data structures for exchanging damage information among different stakeholders. However, those studies do not cover the process of automatic data acquisition and transfer. This study focuses on a framework that incorporates automatic damage data acquisition, transfer, and a damage information model for data exchange. This enables inspectors to use damage data for subsequent analyses and simulations. The proposed framework shows the potentials for a comprehensive damage information model and related (semi-)automatic data acquisition and processing.
The primary objective of initial shape analysis of a cable stayed bridge is to calculate initial installation cable tension forces and to evaluate fabrication camber of main span and pylon providing the final longitudinal profile of the bridge at the end of construction. In addition, the initial cable forces depending on the alternation of the bridge’s shape can be obtained from the analysis, and will be used to provide construction safety during construction. In this research, we conducted numerical experiments for initial shape of Ko-ha bridge, which will be constructed in the near future, using three different typical methods such as continuous beam method, linear truss method, and IIMF (Introducing Initial Member Force) method
The evolution of data exchange and integration standards within the Architectural, Engineering and Construction industry is gradually making the long-held vision of computer-integratedconstruction a reality. The Industry Foundations Classes and CIMSteel Integration Standards are two such standards that have seen remarkable successes over the past few years. Despite successes, these standards support the exchange of product data more than they do process data, especially those processes that are loosely coupled with product models. This paper reports on on-going research to evaluate the adequacy of the IFC and CIS/2 standards to support process modeling in the steel supply chain. Some initial recommendations are made regarding enhancements to the data standards to better support processes.
A categorical perspective towards aerodynamic models for aeroelastic analyses of bridge decks
(2019)
Reliable modelling in structural engineering is crucial for the serviceability and safety of structures. A huge variety of aerodynamic models for aeroelastic analyses of bridges poses natural questions on their complexity and thus, quality. Moreover, a direct comparison of aerodynamic models is typically either not possible or senseless, as the models can be based on very different physical assumptions. Therefore, to address the question of principal comparability and complexity of models, a more abstract approach, accounting for the effect of basic physical assumptions, is necessary.
This paper presents an application of a recently introduced category theory-based modelling approach to a diverse set of models from bridge aerodynamics. Initially, the categorical approach is extended to allow an adequate description of aerodynamic models. Complexity of the selected aerodynamic models is evaluated, based on which model comparability is established. Finally, the utility of the approach for model comparison and characterisation is demonstrated on an illustrative example from bridge aeroelasticity. The outcome of this study is intended to serve as an alternative framework for model comparison and impact future model assessment studies of mathematical models for engineering applications.
This paper extends further the strain smoothing technique in finite elements to 8-noded hexahedral elements (CS-FEM-H8). The idea behind the present method is similar to the cell-based smoothed 4-noded quadrilateral finite elements (CS-FEM-Q4). In CSFEM, the smoothing domains are created based on elements, and each element can be further subdivided into 1 or several smoothing cells. It is observed that: 1) The CS-FEM using a single smoothing cell can produce higher stress accuracy, but insufficient rank and poor displacement accuracy; 2) The CS-FEM using several smoothing cells has proper rank, good displacement accuracy, but lower stress accuracy, especially for nearly incompressible and bending dominant problems. We therefore propose 1) an extension of strain smoothing to 8-noded hexahedral elements and 2) an alternative CS-FEM form, which associates the single smoothing cell issue with multi-smoothing cell one via a stabilization technique. Several numerical examples are provided to show the reliability and accuracy of the present formulation.
Methods with the convergence order p 2 (Newton`s, tangent hyperbolas, tangent parabolas etc.) and their approximate variants are studied. Conditions are presented under which the approximate variants preserve their convergence rate intrinsic to these methods and some computational aspects (possibilities to organize parallel computation, globalization of a method, the solution of the linear equations versus the matrix inversion at every iteration etc.) are discussed. Polyalgorithmic computational schemes (hybrid methods) combining the best features of various methods are developed and possibilities of their application to numerical solution of two-point boundary-value problem in ordinary differential equations and decomposition-coordination problem in convex programming are analyzed.
Due to the importance of identifying crop cultivars, the advancement of accurate assessment of cultivars is considered essential. The existing methods for identifying rice cultivars are mainly time-consuming, costly, and destructive. Therefore, the development of novel methods is highly beneficial. The aim of the present research is to classify common rice cultivars in Iran based on color, morphologic, and texture properties using artificial intelligence (AI) methods. In doing so, digital images of 13 rice cultivars in Iran in three forms of paddy, brown, and white are analyzed through pre-processing and segmentation of using MATLAB. Ninety-two specificities, including 60 color, 14 morphologic, and 18 texture properties, were identified for each rice cultivar. In the next step, the normal distribution of data was evaluated, and the possibility of observing a significant difference between all specificities of cultivars was studied using variance analysis. In addition, the least significant difference (LSD) test was performed to obtain a more accurate comparison between cultivars. To reduce data dimensions and focus on the most effective components, principal component analysis (PCA) was employed. Accordingly, the accuracy of rice cultivar separations was calculated for paddy, brown rice, and white rice using discriminant analysis (DA), which was 89.2%, 87.7%, and 83.1%, respectively. To identify and classify the desired cultivars, a multilayered perceptron neural network was implemented based on the most effective components. The results showed 100% accuracy of the network in identifying and classifying all mentioned rice cultivars. Hence, it is concluded that the integrated method of image processing and pattern recognition methods, such as statistical classification and artificial neural networks, can be used for identifying and classification of rice cultivars.
Determining the earthquake hazard of any settlement is one of the primary studies for reducing earthquake damage. Therefore, earthquake hazard maps used for this purpose must be renewed over time. Turkey Earthquake Hazard Map has been used instead of Turkey Earthquake Zones Map since 2019. A probabilistic seismic hazard was performed by using these last two maps and different attenuation relationships for Bitlis Province (Eastern Turkey) were located in the Lake Van Basin, which has a high seismic risk. The earthquake parameters were determined by considering all districts and neighborhoods in the province. Probabilistic seismic hazard analyses were carried out for these settlements using seismic sources and four different attenuation relationships. The obtained values are compared with the design spectrum stated in the last two earthquake maps. Significant differences exist between the design spectrum obtained according to the different exceedance probabilities. In this study, adaptive pushover analyses of sample-reinforced concrete buildings were performed using the design ground motion level. Structural analyses were carried out using three different design spectra, as given in the last two seismic design codes and the mean spectrum obtained from attenuation relationships. Different design spectra significantly change the target displacements predicted for the performance levels of the buildings.
Recently, the demand for residence and usage of urban infrastructure has been increased, thereby resulting in the elevation of risk levels of human lives over natural calamities. The occupancy demand has rapidly increased the construction rate, whereas the inadequate design of structures prone to more vulnerability. Buildings constructed before the development of seismic codes have an additional susceptibility to earthquake vibrations. The structural collapse causes an economic loss as well as setbacks for human lives. An application of different theoretical methods to analyze the structural behavior is expensive and time-consuming. Therefore, introducing a rapid vulnerability assessment method to check structural performances is necessary for future developments. The process, as mentioned earlier, is known as Rapid Visual Screening (RVS). This technique has been generated to identify, inventory, and screen structures that are potentially hazardous. Sometimes, poor construction quality does not provide some of the required parameters; in this case, the RVS process turns into a tedious scenario. Hence, to tackle such a situation, multiple-criteria decision-making (MCDM) methods for the seismic vulnerability assessment opens a new gateway. The different parameters required by RVS can be taken in MCDM. MCDM evaluates multiple conflicting criteria in decision making in several fields. This paper has aimed to bridge the gap between RVS and MCDM. Furthermore, to define the correlation between these techniques, implementation of the methodologies from Indian, Turkish, and Federal Emergency Management Agency (FEMA) codes has been done. The effects of seismic vulnerability of structures have been observed and compared.
Complex vortex flow patterns around bridge piers, especially during floods, cause scour process that can result in the failure of foundations. Abutment scour is a complex three-dimensional phenomenon that is difficult to predict especially with traditional formulas obtained using empirical approaches such as regressions. This paper presents a test of a standalone Kstar model with five novel hybrid algorithm of bagging (BA-Kstar), dagging (DA-Kstar), random committee (RC-Kstar), random subspace (RS-Kstar), and weighted instance handler wrapper (WIHWKstar) to predict scour depth (ds) for clear water condition. The dataset consists of 99 scour depth data from flume experiments (Dey and Barbhuiya, 2005) using abutment shapes such as vertical, semicircular and 45◦ wing. Four dimensionless parameter of relative flow depth (h/l), excess abutment Froude number (Fe), relative sediment size (d50/l) and relative submergence (d50/h) were considered for the prediction of relative scour depth (ds/l). A portion of the dataset was used for the calibration (70%), and the remaining used for model validation. Pearson correlation coefficients helped deciding relevance of the input parameters combination and finally four different combinations of input parameters were used. The performance of the models was assessed visually and with quantitative metrics. Overall, the best input combination for vertical abutment shape is the combination of Fe, d50/l and h/l, while for semicircular and 45◦ wing the combination of the Fe and d50/l is the most effective input parameter combination. Our results show that incorporating Fe, d50/l and h/l lead to higher performance while involving d50/h reduced the models prediction power for vertical abutment shape and for semicircular and 45◦ wing involving h/l and d50/h lead to more error. The WIHW-Kstar provided the highest performance in scour depth prediction around vertical abutment shape while RC-Kstar model outperform of other models for scour depth prediction around semicircular and 45◦ wing.
The synchronous distributed processing of common source code in the software development process is supported by well proven methods. The planning process has similarities with the software development process. However, there are no consistent and similarly successful methods for applications in construction projects. A new approach is proposed in this contribution.
The research of the best building design requires a concerted design approach of both structure and foundation. Our work is an application of this approach. Our objective is also to create an interactive tool, which will be able to define, at the early design stages, the orientations of structure and foundation systems that satisfy as well as possible the client and the architect. If the concerns of these two actors are primarily technical and economical, they also wish to apprehend the environmental and social dimensions of their projects. Thus, this approach bases on alternative studies and on a multi-criterion analysis. In this paper, we present the context of our work, the problem formulation, which allows a concerted design of Structure and Foundation systems and the feasible solutions identifying process.
The contribution focuses on the development of a basic computational scheme that provides a suitable calculation environment for the coupling of analytical near-field solutions with numerical standard procedures in the far-field of the singularity. The proposed calculation scheme uses classical methods of complex function theory, which can be generalized to 3-dimensional problems by using the framework of hypercomplex analysis. The adapted approach is mainly based on the factorization of the Laplace operator EMBED Equation.3 by the Cauchy-Riemann operator EMBED Equation.3 , where exact solutions of the respective differential equation are constructed by using an orthonormal basis of holomorphic and anti-holomorphic functions.
A coupled thermo-hydro-mechanical model of jointed hard rock for compressed air energy storage
(2014)
Renewable energy resources such as wind and solar are intermittent, which causes instability when being connected to utility grid of electricity. Compressed air energy storage (CAES) provides an economic and technical viable solution to this problem by utilizing subsurface rock cavern to store the electricity generated by renewable energy in the form of compressed air. Though CAES has been used for over three decades, it is only restricted to salt rock or aquifers for air tightness reason. In this paper, the technical feasibility of utilizing hard rock for CAES is investigated by using a coupled thermo-hydro-mechanical (THM) modelling of nonisothermal gas flow. Governing equations are derived from the rules of energy balance, mass balance, and static equilibrium. Cyclic volumetric mass source and heat source models are applied to simulate the gas injection and production. Evaluation is carried out for intact rock and rock with discrete crack, respectively. In both cases, the heat and pressure losses using air mass control and supplementary air injection are compared.
For the safe and efficient operation of dams, frequent monitoring and maintenance are required. These are usually expensive, time consuming, and cumbersome. To alleviate these issues, we propose applying a wave-based scheme for the location and quantification of damages in dams.
To obtain high-resolution “interpretable” images of the damaged regions, we drew inspiration from non-linear full-multigrid methods for inverse problems and applied a new cyclic multi-stage full-waveform inversion (FWI) scheme. Our approach is less susceptible to the stability issues faced by the standard FWI scheme when dealing with ill-posed problems. In this paper, we first selected an optimal acquisition setup and then applied synthetic data to demonstrate the capability of our approach in identifying a series of anomalies in dams by a mixture of reflection and transmission tomography. The results had sufficient robustness, showing the prospects of application in the field of non-destructive testing of dams.
Interactive scientific visualizations are widely used for the visual exploration and examination of physical data resulting from measurements or simulations. Driven by technical advancements of data acquisition and simulation technologies, especially in the geo-scientific domain, large amounts of highly detailed subsurface data are generated. The oil and gas industry is particularly pushing such developments as hydrocarbon reservoirs are increasingly difficult to discover and exploit. Suitable visualization techniques are vital for the discovery of the reservoirs as well as their development and production. However, the ever-growing scale and complexity of geo-scientific data sets result in an expanding disparity between the size of the data and the capabilities of current computer systems with regard to limited memory and computing resources.
In this thesis we present a unified out-of-core data-virtualization system supporting geo-scientific data sets consisting of multiple large seismic volumes and height-field surfaces, wherein each data set may exceed the size of the graphics memory or possibly even the main memory. Current data sets fall within the range of hundreds of gigabytes up to terabytes in size. Through the mutual utilization of memory and bandwidth resources by multiple data sets, our data-management system is able to share and balance limited system resources among different data sets. We employ multi-resolution methods based on hierarchical octree and quadtree data structures to generate level-of-detail working sets of the data stored in main memory and graphics memory for rendering. The working set generation in our system is based on a common feedback mechanism with inherent support for translucent geometric and volumetric data sets. This feedback mechanism collects information about required levels of detail during the rendering process and is capable of directly resolving data visibility without the application of any costly occlusion culling approaches. A central goal of the proposed out-of-core data management system is an effective virtualization of large data sets. Through an abstraction of the level-of-detail working sets, our system allows developers to work with extremely large data sets independent of their complex internal data representations and physical memory layouts.
Based on this out-of-core data virtualization infrastructure, we present distinct rendering approaches for specific visualization problems of large geo-scientific data sets. We demonstrate the application of our data virtualization system and show how multi-resolution data can be treated exactly the same way as regular data sets during the rendering process. An efficient volume ray casting system is presented for the rendering of multiple arbitrarily overlapping multi-resolution volume data sets. Binary space-partitioning volume decomposition of the bounding boxes of the cube-shaped volumes is used to identify the overlapping and non-overlapping volume regions in order to optimize the rendering process. We further propose a ray casting-based rendering system for the visualization of geological subsurface models consisting of multiple very detailed height fields. The rendering of an entire stack of height-field surfaces is accomplished in a single rendering pass using a two-level acceleration structure, which combines a minimum-maximum quadtree for empty-space skipping and sorted lists of depth intervals to restrict ray intersection searches to relevant height fields and depth ranges. Ultimately, we present a unified rendering system for the visualization of entire geological models consisting of highly detailed stacked horizon surfaces and massive volume data. We demonstrate a single-pass ray casting approach facilitating correct visual interaction between distinct translucent model components, while increasing the rendering efficiency by reducing processing overhead of potentially invisible parts of the model. The combination of image-order rendering approaches and the level-of-detail feedback mechanism used by our out-of-core data-management system inherently accounts for occlusions of different data types without the application of costly culling techniques.
The unified out-of-core data-management and virtualization infrastructure considerably facilitates the implementation of complex visualization systems. We demonstrate its applicability for the visualization of large geo-scientific data sets using output-sensitive rendering techniques. As a result, the magnitude and multitude of data sets that can be interactively visualized is significantly increased compared to existing approaches.
Abstract Developing and emerging tropical Asian countries have encountered fast urban development due to the migration of farmers seeking a better life in the city. This resulted in a lack of appro-priate infrastructure and inappropriate social services in many cities. Municipal solid waste management is no exception and is in fact often placed at the bottom of the list of priorities for the cities’ appropriate urban management plans since laws and regulations must first be for-mulated and implemented. The problem of unmanaged municipal solid waste certainly leads to air pollution, disease, and to soil and water contamination. These problems in tropical climates are compounded with high temperature, high-level humidity, heavy rainfall and frequent flooding. Stagnant water and leachate from waste quickly become the breeding grounds of in-sects, rodents and bacteria, thus creating a health hazard for workers and local populations. Moreover, water and groundwater contamination may lead to serious environmental degrada-tion with direct impacts on water supplies, and in the fast degradation of agricultural products, the backbone of most tropical Asian countries. Many cities still allow or tolerate dumping of waste in uncontrolled sites, and open burning that disperses particulates that most likely contain dioxins and furans. Even with increasingly scarce land availability within or in proximity of the cities, sanitary landfill is still the most often cho-sen disposal method around Asia because of its lower cost when compared to modern treatment systems. Yet, most of these landfill sites do not have proper lining, daily covering, methane recovery devices, leachate control systems, nor do they have long-term closure and monitoring plans, which implies short and long-term hazards. Some municipalities opted for incineration, which usually entails high operation and maintenance costs because of the need for supple-mental fuel and often-inappropriate running conditions. Although tropical conditions appear to favor certain disposal systems such as composting, appropriate technology needs to be identi-fied in order to reduce operation and maintenance costs while ensuring good quality outputs; compost plants have often been closed because of poor quality products due to the high content of plastic and glass particulates in the finished product. Tropical Asian cities are now required to identify affordable and sustainable solutions for the management of their increasing amount of waste generated daily, while ensuring minimal environmental impact, social acceptance and minimal land use. The purpose of this dissertation was to develop a user-friendly decision-making tool for public administrators and government officials in tropical Asian developing and emerging cities. This tool was developed based on a list of selected decision-making issues necessary in making an informed decision. The decision-making tool is to be used by decision-makers in making a pre-liminary assessment of a most appropriate waste management and treatment system for their municipality. Tropical Asian cities must consider a number of issues when deciding on their waste management plan such as the continuously changing quantum and composition of waste associated with the increasing population and income per capita, the high humidity levels, and the often-limited financial resources. Other determinant factors include legal, political, institu-tional, social and technical issues. Furthermore, administrators must realize the importance of each stage involved in waste management, which includes waste generation, collection, trans-port, waste characteristics, disposal and treatment. To better understand the complexity of the issues involved in tropical Asian municipalities, the city of Bangkok, Thailand’s largest city and capital, was selected as a case study for the management of its 9,000 tonnes of waste gen-erated daily. Numerous interviews, meetings along with the review of documents, reports and site visits offered an inside view of the tropical city’s various decision-making issues towards its waste management plan, and examine specific problems encountered by the city’s decision-makers. The review and analysis of the decision-making issues involved in Bangkok’s waste management plan showed how the decision-making tool can be used in various Asian tropical cities. In conclusion, waste management in an emerging tropical country involves specific challenges that need to be addressed. Economical, technical and social criteria need to be fully understood as to capacitate government officials in the selection of the most appropriate urban waste man-agement system. Limited budgets, lack of public awareness and poor systems’ management often cloud decision-makers in choosing what appears to be the best solution in the short term, but more costly over the years. Weather conditions and scarcity of land in proximity of the city make waste management especially challenging. The decision-making framework offers a tool to decision-makers, as to facilitate the understanding and identification of key issues necessary in the formulation of a sustainable urban waste management plan and in the selection of a tech-nically, economically and socially acceptable integrated MSW management system. A detailed feasibility study and master plan will follow the preliminary study as to define the plant´s specifications, its location and its financing.
The purpose of this research is to develop the method to retrieve a building name from the impression of the building. First, the images of the building are registered as database by the questionnaire. Next, the images of the objective building are compared with the degree of matching in image databases, and the building with high synthetic matching degree is retrieved. This system could get a good retrieval result. Moreover, image processing was done, and image databases are trained by neural network from the amount of characteristics of the image, and the retrieval system by image processing was examined.
A Flexible Model for Incorporating Construction Product Data into Building Information Models
(2006)
When considering the integration and interoperability between AEC-FM software applications and construction products' data, it is essential to investigate the state-of-the-art and conduct an extensive review in the literature of both Building Information Models and electronic product catalogues. It was found that there are many reasons and key-barriers that hinder the developed solutions from being implemented. Among the reasons that are attributed to the failure of many previous research projects to achieve this integration aim are the proprietary developments of CAD vendors, the fragmented nature of construction product data i.e. commercial and technical data, the prefabrication versus on-site production, marketing strategies and brand-naming, the referencing of a product to the data of its constituents, availability of life-cycle data in a single point in time where it is needed all over the whole life-cycle of the product itself, taxonomy problems, the inability to extract search parameters from the building information model to participate in the conduction of parametric searches. Finally and most important is keeping the product data in the building information model consistent and up-to-date. Hence, it was found that there is a great potential for construction product data to be integrated to building information models by electronic means in a dynamic and extensible manner that prevents the model from getting obsolete. The study has managed to establish a solution concept that links continually updated and extensible life-cycle product data to a software independent building information model (IFC) all over the life span of the product itself. As a result, the solution concept has managed to reach a reliable building information model that is capable of overcoming the majority of the above mentioned barriers. In the meantime, the solution is capable of referencing, retrieving, updating, and merging product data at any point in time. A distributed network application that represents all the involved parties in the construction product value chain is simulated by real software tools to demonstrate the proof of concept of this research work.
The methods currently used for scheduling building processes have some major advantages as well as disadvantages. The main advantages are the arrangement of the tasks of a project in a clear, easily readable form and the calculation of valuable information like critical paths. The main disadvantage on the other hand is the inflexibility of the model caused by the modeling paradigms. Small changes of the modeled information strongly influence the whole model and lead to the need to change many more details in the plan. In this article an approach is introduced allowing the creation of more flexible schedules. It aims towards a more robust model that lowers the need to change more than a few information while being able to calculate the important propositions of the known models and leading to further valuable conclusions.
Business and engineering knowledge in AEC/FM is captured mainly implicitly in project and corporate document repositories. Even with the increasing integration of model-based systems with project information spaces, a large percentage of the information exchange will further on rely on isolated and rather poorly structured text documents. In this paper we propose an approach enabling the use of product model data as a primary source of engineering knowledge to support information externalisation from relevant construction documents, to provide for domain-specific information retrieval, and to help in re-organising and re-contextualising documents in accordance to the user’s discipline-specific tasks and information needs. Suggested is a retrieval and mining framework combining methods for analysing text documents, filtering product models and reasoning on Bayesian networks to explicitly represent the content of text repositories in personalisable semantic content networks. We describe the proposed basic network that can be realised on short-term using minimal product model information as well as various extensions towards a full-fledged added value integration of document-based and model-based information.
Iso-parametric finite elements with linear shape functions show in general a too stiff element behavior, called locking. By the investigation of structural parts under bending loading the so-called shear locking appears, because these elements can not reproduce pure bending modes. Many studies dealt with the locking problem and a number of methods to avoid the undesirable effects have been developed. Two well known methods are the >Assumed Natural Strain< (ANS) method and the >Enhanced Assumed Strain< (EAS) method. In this study the EAS method is applied to a four-node plane element with four EAS-parameters. The paper will describe the well-known linear formulation, its extension to nonlinear materials and the modeling of material uncertainties with random fields. For nonlinear material behavior the EAS parameters can not be determined directly. Here the problem is solved by using an internal iteration at the element level, which is much more efficient and stable than the determination via a global iteration. To verify the deterministic element behavior the results of common test examples are presented for linear and nonlinear materials. The modeling of material uncertainties is done by point-discretized random fields. To show the applicability of the element for stochastic finite element calculations Latin Hypercube Sampling was applied to investigate the stochastic hardening behavior of a cantilever beam with nonlinear material. The enhanced linear element can be applied as an alternative to higher-order finite elements where more nodes are necessary. The presented element formulation can be used in a similar manner to improve stochastic linear solid elements.
Tropical coral reefs, one of the world’s oldest ecosystems which support some of the highest levels of biodiversity on the planet, are currently facing an unprecedented ecological crisis during this massive human-activity-induced period of extinction. Hence, tropical reefs symbolically stand for the destructive effects of human activities on nature [4], [5]. Artificial reefs are excellent examples of how architectural design can be combined with ecosystem regeneration [6], [7], [8]. However, to work at the interface between the artificial and the complex and temporal nature of natural systems presents a challenge, i.a. in respect to the B-rep modelling legacy of computational modelling.
The presented doctorate investigates strategies on how to apply digital practice to realise what is an essential bulwark to retain reefs in impossibly challenging times. Beyond the main question of integrating computational modelling and high precision monitoring strategies in artificial coral reef design, this doctorate explores techniques, methods, and linking frameworks to support future research and practice in ecology led design contexts.
Considering the many existing approaches for artificial coral reefs design, one finds they often fall short in precisely understanding the relationships between architectural and ecological aspects (e.g. how a surface design and material composition can foster coral larvae settlement, or structural three-dimensionality enhance biodiversity) and lack an integrated underwater (UW) monitoring process. Such a process is necessary in order to gather knowledge about the ecosystem and make it available for design, and to learn whether artificial structures contribute to reef regeneration or rather harm the coral reef ecosystem.
For the research, empirical experimental methods were applied: Algorithmic coral reef design, high precision UW monitoring, computational modelling and simulation, and validated through parallel real-world physical experimentation – two Artificial Reef Prototypes (ARPs) in Gili Trawangan, Indonesia (2012–today). Multiple discrete methods and sub techniques were developed in seventeen computational experiments and applied in a way in which many are cross valid and integrated in an overall framework that is offered as a significant contribution to the field. Other main contributions include the Ecosystem-aware design approach, Key Performance Indicators (KPIs) for coral reef design, algorithmic design and fabrication of Biorock cathodes, new high precision UW monitoring strategies, long-term real-world constructed experiments, new digital analysis methods and two new front-end web-based tools for reef design and monitoring reefs. The methodological framework is a finding of the research that has many technical components that were tested and combined in this way for the very first time.
In summary, the thesis responds to the urgency and relevance in preserving marine species in tropical reefs during this massive extinction period by offering a differentiated approach towards artificial coral reefs – demonstrating the feasibility of digitally designing such ‘living architecture’ according to multiple context and performance parameters. It also provides an in-depth critical discussion of computational design and architecture in the context of ecosystem regeneration and Planetary Thinking. In that respect, the thesis functions as both theoretical and practical background for computational design, ecology and marine conservation – not only to foster the design of artificial coral reefs technically but also to provide essential criteria and techniques for conceiving them.
Keywords: Artificial coral reefs, computational modelling, high precision underwater monitoring, ecology in design.
This paper describes a framework for computer-aided conceptual design of building structures that results from building architectural considerations. The central task that is carried out during conceptual design is the synthesis of the structural system. This paper proposes a methodology for the synthesis of structural solutions. Given the nature of architectural constraints, user-model interactivity is devised as the most suitable computer methodology for driving the structural synthesis process. Taking advantage of the hierarchical organization of the structural system, this research proposes a top-down approach for structural synthesis. Through hierarchical refinement, the approach lends itself to the synthesis of global and local structural solutions. The components required for implementing the proposed methodology are briefly described. The main components have been incorporated in a proof-of-concept prototype that is being tested and validated with actual buildings.
Interactive visualization based on 3D computer graphics nowadays is an indispensable part of any simulation software used in engineering. Nevertheless, the implementation of such visualization software components is often avoided in research projects because it is a challenging and potentially time consuming task. In this contribution, a novel Java framework for the interactive visualization of engineering models is introduced. It supports the task of implementing engineering visualization software by providing adequate program logic as well as high level classes for the visual representation of entities typical for engineering models. The presented framework is built on top of the open source visualization toolkit VTK. In VTK, a visualization model is established by connecting several filter objects in a so called visualization pipeline. Although designing and implementing a good pipeline layout is demanding, VTK does not support the reuse of pipeline layouts directly. Our framework tailors VTK to engineering applications on two levels. On the first level it adds new – engineering model specific – filter classes to VTK. On the second level, ready made pipeline layouts for certain aspects of engineering models are provided. For instance there is a pipeline class for one-dimensional elements like trusses and beams that is capable of showing the elements along with deformations and member forces. In order to facilitate the implementation of a graphical user interface (GUI) for each pipeline class, there exists a reusable Java Swing GUI component that allows the user to configure the appearance of the visualization model. Because of the flexible structure, the framework can be easily adapted and extended to new problem domains. Currently it is used in (i) an object-oriented p-version finite element code for design optimization, (ii) an agent based monitoring system for dam structures and (iii) the simulation of destruction processes by controlled explosives based on multibody dynamics. Application examples from all three domains illustrates that the approach presented is powerful as well as versatile.
A comprehensive framework of information management system for construction projects in China has been established through extensive literature survey and field investigation. It utilizes the potential information technologies and covers the practical management patterns as well as the major aspects of construction project management. It can be used to guide and evaluate the design of the information management systems for construction projects in order to make the system to be applicable to a wide variety of construction projects and survive the changes in project management.