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In Germany, bridges have an average age of 40 years. A bridge consumes between 0.4% and 2% of its construction cost per year over its entire life cycle. This means that up to 80% of the construction cost are additionally needed for operation, inspection, maintenance, and destruction. Current practices rely either on paperbased inspections or on abstract specialist software. Every application in the inspection and maintenance sector uses its own data model for structures, inspections, defects, and maintenance. Due to this, data and properties have to be transferred manually, otherwise a converter is necessary for every data exchange between two applications. To overcome this issue, an adequate model standard for inspections, damage, and maintenance is necessary. Modern 3D models may serve as a single source of truth, which has been suggested in the Building Information Modeling (BIM) concept. Further, these models offer a clear visualization of the built infrastructure, and improve not only the planning and construction phases, but also the operation phase of construction projects. BIM is established mostly in the Architecture, Engineering, and Construction (AEC) sector to plan and construct new buildings. Currently, BIM does not cover the whole life cycle of a building, especially not inspection and maintenance. Creating damage models needs the building model first, because a defect is dependent on the building component, its properties and material. Hence, a building information model is necessary to obtain meaningful conclusions from damage information. This paper analyzes the requirements, which arise from practice, and the research that has been done in modeling damage and related information for bridges. With a look at damage categories and use cases related to inspection and maintenance, scientific literature is discussed and synthesized. Finally, research gaps and needs are identified and discussed.
Personalisierte Lüftung (PL) kann die thermische Behaglichkeit sowie die Qualität der eingeatmeten Atemluft verbessern, in dem jedem Arbeitsplatz Frischluft separat zugeführt wird. In diesem Beitrag wird die Wirkung der PL auf die thermische Behaglichkeit der Nutzer unter sommerlichen Randbedingungen untersucht. Hierfür wurden zwei Ansätze zur Bewertung des Kühlungseffekts der PL untersucht: basierend auf (1) der äquivalenten Temperatur und (2) dem thermischen Empfinden. Grundlage der Auswertung sind in einer Klimakammer gemessene sowie numerisch simulierte Daten. Vor der Durchführung der Simulationen wurde das numerische Modell zunächst anhand der gemessenen Daten validiert. Die Ergebnisse zeigen, dass der Ansatz basierend auf dem thermischen Empfinden zur Evaluierung des Kühlungseffekts der PL sinnvoller sein kann, da bei diesem die komplexen physiologischen Faktoren besser berücksichtigt werden.
Für eine Abschätzung des Heizwärmebedarfs von Gebäuden und Quartieren können thermisch-energetische Simulationen eingesetzt werden. Grundlage dieser Simulationen sind geometrische und physikalische Gebäudemodelle. Die Erstellung des geometrischen Modells erfolgt in der Regel auf Basis von Bauplänen oder Vor-Ort-Begehungen, was mit einem großen Recherche- und Modellierungsaufwand verbunden ist. Spätere bauliche Veränderungen des Gebäudes müssen häufig manuell in das Modell eingearbeitet werden, was den Arbeitsaufwand zusätzlich erhöht. Das physikalische Modell stellt die Menge an Parametern und Randbedingungen dar, welche durch Materialeigenschaften, Lage und Umgebungs-einflüsse gegeben sind. Die Verknüpfung beider Modelle wird innerhalb der entsprechenden Simulations-software realisiert und ist meist nicht in andere Softwareprodukte überführbar. Mithilfe des Building Information Modeling (BIM) können Simulationsdaten sowohl konsistent gespeichert als auch über Schnittstellen mit entsprechenden Anwendungen ausgetauscht werden. Hierfür wird eine Methode vorgestellt, die thermisch-energetische Simulationen auf Basis des standardisierten Übergabe-formats Industry Foundation Classes (IFC) inklusive anschließender Auswertungen ermöglicht. Dabei werden geometrische und physikalische Parameter direkt aus einem über den gesamten Lebenszyklus aktuellen Gebäudemodell extrahiert und an die Simulation übergeben. Dies beschleunigt den Simulations-prozess hinsichtlich der Gebäudemodellierung und nach späteren baulichen Veränderungen. Die erarbeite-te Methode beruht hierbei auf einfachen Modellierungskonventionen bei der Erstellung des Bauwerksinformationsmodells und stellt eine vollständige Übertragbarkeit der Eingangs- und Ausgangswerte sicher.
Thermal building simulation based on BIM-models. Thermal energetic simulations are used for the estimation of the heating demand of buildings and districts. These simulations are based on building models containing geometrical and physical information. The creation of geometrical models is usually based on existing construction plans or in situ assessments which demand a comparatively big effort of investigation and modeling. Alterations, which are later applied to the structure, request manual changes of the related model, which increases the effort additionally. The physical model represents the total amount of parameters and boundary conditions that are influenced by material properties, location and environmental influences on the building. The link between both models is realized within the correspondent simulation soft-ware and is usually not transferable to other software products. By Applying Building Information Modeling (BIM) simulation data is stored consistently and an exchange to other software is enabled. Therefore, a method which allows a thermal energetic simulation based on the exchange format Industry Foundation Classes (IFC) including an evaluation is presented. All geometrical and physical information are extracted directly from the building model that is kept up-to-date during its life cycle and transferred to the simulation. This accelerates the simulation process regarding the geometrical modeling and adjustments after later changes of the building. The developed method is based on simple conventions for the creation of the building model and ensures a complete transfer of all simulation data.
Für eine Abschätzung des Heizwärmebedarfs von Gebäuden und Quartieren können thermisch-energetische Simulationen eingesetzt werden. Grundlage dieser Simulationen sind geometrische und physikalische Gebäudemodelle. Die Erstellung des geometrischen Modells erfolgt in der Regel auf Basis von Bauplänen oder Vor-Ort-Begehungen, was mit einem großen Recherche- und Modellierungsaufwand verbunden ist. Spätere bauliche Veränderungen des Gebäudes müssen häufig manuell in das Modell eingearbeitet werden, was den Arbeitsaufwand zusätzlich erhöht. Das physikalische Modell stellt die Menge an Parametern und Randbedingungen dar, welche durch Materialeigenschaften, Lage und Umgebungs-einflüsse gegeben sind. Die Verknüpfung beider Modelle wird innerhalb der entsprechenden Simulations-software realisiert und ist meist nicht in andere Softwareprodukte überführbar.
Mithilfe des Building Information Modeling (BIM) können Simulationsdaten sowohl konsistent gespeichert als auch über Schnittstellen mit entsprechenden Anwendungen ausgetauscht werden. Hierfür wird eine Methode vorgestellt, die thermisch-energetische Simulationen auf Basis des standardisierten Übergabe-formats Industry Foundation Classes (IFC) inklusive anschließender Auswertungen ermöglicht. Dabei werden geometrische und physikalische Parameter direkt aus einem über den gesamten Lebenszyklus aktuellen Gebäudemodell extrahiert und an die Simulation übergeben. Dies beschleunigt den Simulations-prozess hinsichtlich der Gebäudemodellierung und nach späteren baulichen Veränderungen. Die erarbeite-te Methode beruht hierbei auf einfachen Modellierungskonventionen bei der Erstellung des Bauwerksinformationsmodells und stellt eine vollständige Übertragbarkeit der Eingangs- und Ausgangswerte sicher.
Thermal building simulation based on BIM-models. Thermal energetic simulations are used for the estimation of the heating demand of buildings and districts. These simulations are based on building models containing geometrical and physical information. The creation of geometrical models is usually based on existing construction plans or in situ assessments which demand a comparatively big effort of investigation and modeling. Alterations, which are later applied to the structure, request manual changes of the related model, which increases the effort additionally. The physical model represents the total amount of parameters and boundary conditions that are influenced by material properties, location and environmental influences on the building. The link between both models is realized within the correspondent simulation soft-ware and is usually not transferable to other software products.
By Applying Building Information Modeling (BIM) simulation data is stored consistently and an exchange to other software is enabled. Therefore, a method which allows a thermal energetic simulation based on the exchange format Industry Foundation Classes (IFC) including an evaluation is presented. All geometrical and physical information are extracted directly from the building model that is kept up-to-date during its life cycle and transferred to the simulation. This accelerates the simulation process regarding the geometrical modeling and adjustments after later changes of the building. The developed method is based on simple conventions for the creation of the building model and ensures a complete transfer of all simulation data.
Traditionally, buildings in the Inner Himalayan valleys of Bhutan were constructed from rammed earth in the western regions and quarry stone in the central and eastern regions. Whilst basic architectural design elements have been retained, the construction methods have however changed over recent decades alongside expectations for indoor thermal comfort. Nevertheless, despite the need for space heating, thermal building performance remains largely unknown. Furthermore, no dedicated climate data is available for building performance assessments. This paper establishes such climatological information for the capital Thimphu and presents an investigation of building physics properties of traditional and contemporary building types. In a one month field study 10 buildings were surveyed, looking at building air tightness, indoor climate, wall U-values and water absorption of typical wall construction materials. The findings highlight comparably high wall U-values of 1.0 to 1.5 W/m²K for both current and historic constructions. Furthermore, air tightness tests show that, due to poorly sealed joints between construction elements, windows and doors, many buildings have high infiltration rates, reaching up to 5 air changes per hour. However, the results also indicate an indoor climate moderating effect of more traditional earth construction techniques. Based on these survey findings basic improvements are being suggested.
This work is based on the concept that the structure of a city can be defined by six basic urban patterns. To enable more complex urban planning as a long-term objective I have developed a simulation method for generating these basic patterns and for combining them to form various structures. The generative process starts with the two-dimensional organisation of streets followed by the parceling of the remaining areas. An agent-based diffusion-contact model is the basis of these first two steps. Then, with the help of cellular automata, the sites for building on are defined and a three-dimensional building structure is derived. I illustrate the proposed method by showing how it can be applied to generate possible structures for an urban area in the city of Munich.
Der vorliegende Text beschreibt ein computerbasiertes Verfahren zur Lösung von Layout-problemen in Architektur und Städtebau, welches mit möglichst wenig Problemwissen auskommt und schnell brauchbare Ergebnisse liefert, die durch schrittweises Hinzufügen von Problemwissen interaktiv weiter ausgearbeitet werden können. Für das generative Verfahren wurde eine Evolutions-Strategie verwendet, die mit Mechanismen zur Kollisionserkennung und virtuellen Federn zu einem hybriden Algorithmus kombiniert wurde. Dieser dient erstens der Lösung des Problems der Dichten Packung von Rechtecken sowie zweitens der Herstellung bestimmter topologischer Beziehungen zwischen diesen Rechtecken. Die Bearbeitung beider Probleme wird durch schrittweise Erweiterung grundlegender Verfahren untersucht, wobei die einzelnen Schritte anhand von Performancetests miteinander verglichen werden. Am Ende wird ein iterativer Algorithmus vorgestellt, der einerseits optimale Lösungen garantiert und andererseits diese Lösungen in einer für eine akzeptable Nutzerinteraktion ausreichenden Geschwindigkeit generiert.
Entwerfen Versionieren: Probleme und Lösungsansätze für die Organisation verteilter Entwurfsprozesse
(2011)
Entwerfen ist ein komplexer Vorgang. Soll dieser Vorgang nicht allein, sondern räumlich verteilt mit mehreren Beteiligten gemeinsam stattfinden, so sind digitale Werkzeuge zur Unterstützung dieses Prozesses unumgänglich. Die Verwendung von Werkzeugen für Ent-wurfsprozesse bedeutet jedoch immer auch eine Manipulation des zu unterstützenden Prozesses selbst. Im Falle von Werkzeugen zur Unterstützung der Kollaboration mehrerer Beteiligter stellen die implementierten Koordinationsmechanismen solche prozessbeeinflussenden Faktoren dar. Damit diese Mechanismen, entsprechend der Charakteristika kreativer Prozesse, so flexibel wie möglich gestaltet werden können, liegt die Anforderung auf technischer Ebene darin, ein geeignetes Konzept für eine nachvollziehbare Speicherung (Versionierung) der stattfindenden Entwurfshandlungen zu schaffen. Der vorliegende Artikel beschäftigt sich mit dem Thema der Entwurfsversionierung in computergestützten kollaborativen Arbeitsumgebungen. Vor dem Hintergrund, dass die Versionierung den kreativen Entwurfsprozess möglichst wenig manipulieren soll, werden technische sowie konzeptionelle Probleme der diskutiert und Lösungsansätze für diese vorgestellt.
Monitoring systems usually used to control tailings, primarily pore water pressure gages and observation wells, are not self evidently representative for mechanical considerations. Therefore an effective risk assessment and risk management is necessary to get additional information to determine indicators for critical situations. Several tailings observations showed an alteration in chemical and radiological parameters during rising saturation induced by climatic changes. These parameters are appropriate to stress indices. A systematically research on correlations between changes in stress indices and the phreatic surface is part of the research activities of the Bauhaus University in Weimar. The contribution presents the principle of this kind of monitoring, the soil mechanical background, details of the equipment and first results.
The paper analyses the application of 3D gaming technologies in the simulation of processes associated with human resources and machinery on construction sites in order to determine process costs. It addresses the problem of detailing in process simulation. The authors outline special boundary conditions for the simulation of cost-relevant resource processes on virtual construction sites. The approach considers different needs for detailing in process simulation during the planning and building phase. For simulation of process costs on a construction site (contractors view) the level of detail has to be set to high. A prototype for determination of process durations (and hereby process costs) developed at the Bauhaus University Weimar is presented as a result of ongoing researches on detailing in process simulation. It shows the method of process cost determination on a high level of detail (game between excavator and truck) through interaction with the virtual environment of the site.
Der Einsatz von CAD-Applikationen hat die Planungsarbeit im Bauwesen entscheidend verändert. In der Entwurfsplanung sind die Änderungen bereits deutlich erkennbar. Seit der Anwendung von dreidimensionalen Planungswerkzeugen kann der Bauherr das Bauwerk in seiner virtuellen Gesamtheit am Computer betrachten und bewerten. Dies bietet viele Vorteile. So ist der Planer gezwungen alle wesentlichen Details a priori exakt zu planen, wodurch viele Fehler vermieden werden können. Dies bietet insbesondere für Planungen in Baubetrieben, z.B. im Rahmen der Arbeitsvorbereitung, neue Einsatzmöglichkeiten.
Eine der wichtigsten Aufgaben und Herausforderungen der Bauinformatik ist gegenwärtig die Realisierung des durchgängigen, fachübergreifenden Datenflusses im Planungsprozeß eines Bauvorhabens. Im Hinblick auf die internationale Wettbewerbsfähigkeit der deutschen Bauwirtschaft ist es unumgänglich, vorhandene Effizienzpotentiale in der Bauplanung auszuschöpfen, welche durch eine qualitative Verbesserung der Planung sowie durch eine Verringerung der Bearbeitungszeit aller beteiligten Fachplanern erreicht werden können. Nach dem gegenwärtigen Stand der Technik werden die Informationsobjekte standardisiert, damit sie durchgängig nutzbar sind. Diese werden in einem allgemeingültigen Format den speziellen Programmen der Fachplaner zur Verfügung gestellt. In dieser Arbeit wird der Ansatz verfolgt, eine Integration durch die Standardisierung der Kommunikation zwischen den Informationsobjekten und ihren Anwendungsprogrammen zu erreichen. Dabei kann auf die Standardisierung der zu übertragenden Objekte verzichtet werden. Ziel der Ausarbeitung ist die Definition von implementationstechnischen Regeln, die alle auszutauschenden Objekte sowie die Anwendungen, die solche Objekte aufnehmen wollen, erfüllen müssen. Die Bearbeitung der Objekte soll in den gewohnten Anwendungen in unveränderter Weise erfolgen.
For modeling of singular fields of stresses and deformations in elasters with a crack is offered to use of three-dimesional a special finite element. Weak compessible of elasters is taken into account on the basis of threefold approximation of fields of displacements, deformations and function of volume change. At intensive cyclic loading of the elastomer constructions with a crack it is necessary to take into account warming and large deformations at the crack top. The stress-deformed state elasters with a crack is determined from the decision of a nonlinear problem by a modified method Newton-Kantorovich. Account stress intensity factors for a rectangular plate with a various arrangement of a through crack is executed. Process of development of a surface crack and dissipative warming in prismatic a element of shift is investigated.
Die Gesamtheit der Produktinformationen im Bauwesen stellt sich als sehr inkonsistente und redundante Informationsmenge dar. Die Hersteller stehen vor der Aufgabe, diese Produktinformationen nicht nur in der üblichen Katalogform sondern auch in neuen Medien wie CD-ROM und WWW zu publizieren. Einmal betriebener Erfassungsaufwand muß sich dabei durch eine einfache Mehrfachverwendung der Daten rentieren. Wegen seiner technologischen Eigenschaften eignet sich das WWW sehr gut als primäre Quelle für Produktinformationen. Vor allem wegen der möglichen Aktualität sollte es Grundlage für Publikationen in den anderen Medien sein. Mit verhältnismäßig geringem Aufwand lassen sich die WWW-Präsentation von Produktdaten so strukturieren, daß eine automatisierte Erfassung und Verarbeitung dieser Daten vereinfacht wird. So kann die Datenkonsistenz von der visuellen Präsentation in herkömmlichen Katalogen bis zur automatisch erstellten Produktdatenbank durchgängig gesichert werden. Vor dem Hintergrund der von Schnittstellenproblemen, heterogener Softwarestruktur und unzureichender Ausnutzung der Möglichkeiten der Informatik gekennzeichneten Situation im Bauwesen wird in generalisierter Ansatz mittels SGML vorgestellt. Mit einem derartigen Datenangebot werden neue, verteilte und vernetzte Anwendungen auf Grundlage derselben Produktdaten ermöglicht.
In the rpocess of project construction organization under conditions of limited resources the problem of investor arises, which in onecriteria setting is as follows N invsted projects reindexed i=1,2,...,n are considered, initial parameters of the problem are:- duraion of iproject construction, - expected profit per unit of time from i project after putting it info operation ,-the time fixed , after the expiry of it a fine is paid for each overdued unit of time units in number. The investor resources are limited, i.e., at every moment of time investor can provid delivering of necessary resources only for one project .Any admissible problem decision of investor represents one of n! permutation of of numbers 1,2,..,n. X={x}-is the set of all admissible solutions (SAS) of this problem . In works of different authors the quality of decision is evaluated either by objective function (OF) of the type MINSUM where,by the objective function of the of the type MINMAX
Pseudorigidity method for solving the problem of limit equilibrium of rigid-plastic constructions
(1997)
1.Design calculations , based upon the theory elasticity , cannot completely satisfy engineers and designers , because cannot answer to basic question about overload capability . Only design calculations of limit equilibrium of rigid-plastic constructions can answer to this question completely enough. As a rule , such design calculations are made issue from hypothesis, that material of construction has rigid-plastic diagram Prandtl .This scheme of calculation gives qualitatively more correct results, then usual calculation, based upon law Hooke’s , and allows more really estimate ultimate strength of construction due to different loads. Universal algorithms for solving the problem of limit equilibrium have been created since the middle of the 60’s.These algorithms are based upon two basic theorems about limit analysis - static and kinetics. It was found , that with the help of above-mentioned theorems the problem of limit equilibrium can be formulated as a problem of linear programming (for linear yield) or nonlinear programming (for yield Guber-Mizes). The method of linear programming conformably to calculation of rod systems got the most development in the reports Prager W. [1] and Chiras A. [ 2 ]. The method of linear programming conformably to plates and shells was widely used by Rganizin A.[3]. [3[ contains more full bibliography about this problem. Calculation of limit equilibrium with the help of linear and nonlinear programming has a few significant lacks: - complexity and laboriousness preliminary preparation of problem for PC; - necessity to use special program means , which are not in usual program packet for strength analysis. Author worked out a new method about design calculation of limit equilibrium without above-mentioned lacks . The method is based upon analogy of relations between internal generalized efforts and generalized deformations in elastic system and between generalized efforts and velocities of change generalized deformations in rigid-plastic system. Because later rigid-plastic deformation would be treated as an elastic deformation in the system with special constructed rigidities , this method could be called >pseudorigidity method<.
Problem of discretic programming in conditions of manycriterial is considered. Set of work, being subject to fulfilment, is available. Are certain also: set of the executors; set, machines; set of resources (materials, semifinished items and etc.) and other set. As a functional complex name set, which will be formed, when on one representative of each of the specified sets is nominated to one working place. The allowable decision of a examined problem represents set of not crossed complexes provided that, for each working place one functional complex is certain in the accuracy. The elementary case of a formulated above problem is known under the name >a problem about purposes< [1], when the complex is defined as a pair >an executor - working place<. In case of three-element complexes we come to a problem about three-combinations. In a general case the complex consists from m of elements and the problem of formation of m-element complexes is formulated on the m-colour column.
Model of stressed-strained State of Multilayer Masses with regard for Non-Ideal Contact of Layers
(1997)
Thus, mathematical model stressed- strained of a condition of layered masses is constructed. The model has high accuracy. It allows to simulate slippery contact of layers without friction. Thus not the order of permitting system of the equations is increased, and at its realization the method of fenite elements does not increase quantity of required degrees freedom. The differential operators included in system the equations are similar known in the classical theory of shells. It facilitates construction of a finite element. Presence in system of the differential equations of derivative of external forces allows to use her for the decision of contact problems with a stain of contact commensurable with thickness of a masses.
Analytical models, describing oscillations of systems of interconnected solid and deformable bodies,making a complex movement in fields of inertia forces and gravitation forces, are resulted. Method of numerical investigation of dynamics of the specified systems, based on sharing of parameter prolongation method, Newton-Kantorovich algorithm, Flocke and Liapunov hteories, is developed. On the basis of constructed analytical models and numerical techniques a new, practically important problems of dynamics of systems, consisting of solid bodies, flexible rods, membranes and soft shells, which make a complex movement in fields of forces of inertia and gravity are solved. The received results are used during designing of responsible elements of structures, making a complex movement, which find application in construction and mechanical engineering.
The phenomenological and computational aspects of the various damage models applications for the low and multi cyclic fatigue processes are investigated. Damage is considered as internal state variable, describing macroscopic effects of the progressive material degradation, within the framework of continuum damage mechanics. Present analysis is restricted to the case of isotropic damage, which can be modeled by a scalar variable. The strain, force and power types of kinetic equations for the damage evolution description are considered. The original mixed strain-power type damage model is developed for taking into account the different physical fracture mechanism in monotone and cyclic loading. The constitutive equations of plastic flow theory coupled and uncoupled to damage has been considered. The rational algorithm of implementation into finite element code is considered for developed damage models. Set of the computational experiments has been carried out for the various structures (huge aerials, pipelines, fastening units, vessel of nuclear reactor) and cases of loading. The comparison of the predictions of the developed model with experimental data is performed for 1X18H10T steel tubular specimens for complex paths of loading and for complex profiles beams under cyclic loading. Damage field distribution is the basic information for the prediction of crack initiation in structures. The developed method of structural parameter for stress concentration zones is discussed for correcting of crack location. It allows to describe the crack initiation near surface domain as observe in numerous experiments.
In the design of a structure, the implementation of reliable soil-foundation-structure interaction into the analysis process plays a very important role. The paper presents a determination of parameters of a suitably chosen soil-foundation model and their influence on the structure response. Since the mechanical data for the structure can be determined with satisfactory accuracy, the properties of the soil-foundation model were identified using measured dynamic response of the real structure. A simple model describing soil-foundation structure was incorporated into the classical 3-D finite element analysis of the structure with commercial software. Results obtained from the measured data on the pier were afterwards compared with those obtained with the finite model of the pier-foundation-soil structure. On the basis of this comparison the coefficients describing the properties in the soil-foundation model were adjusted until the calculated dynamic response coincided with the measured ones. In this way, the difference between both results was reduced to 1%. Full-scale tests measuring eigenmotion of the bridge were performed through all erection stages of the new bridge in Maribor. In this way an effective and experimentally verified 3-D model for a complex dynamic analysis of the bridge under the earthquake loading was obtained. The significant advantage of the obtained model is that it was updated on the basis of the dynamic measurements thus improving the model on the basis of in-situ geomechanical measurements. The model is very accurate in describing the upper structure and economical in describing the soil mass thus representing an optimal solution regarding computational efforts.
The frame of this paper is the development of methods and procedures for the description of the motion of an arbitrary shaped foundation. Since the infinite half-space cannot be properly described by a model of finite dimensions without violating the radiation condition, the basic problems are infinite dimensions of the half-space as well as its non-homogeneous nature. Consequently, an approach has been investigated to solve this problem indirectly by developing Green's function in which the non-homogeneity and the infiniteness of the half-space has been included. When the Green's function is known, the next step will be the evaluation of contact stresses acting between the foundation and the surface of the half-space through an integral equation. The equation should be solved in the area of the foundation using Green's function as the kernel. The derivation of three-dimensional Green's function for the homogeneous half-space (Kobayashi and Sasaki 1991) has been made using the potential method. Partial differential equations occurring in the problem have been made ordinary ones through the Hankel integral transform. The general idea for obtaining the three-dimensional Green's function for the layered half-space is similar. But in that case some additional phenomena may occur. One of them is the possibility of the appearance of Stonely surface waves propagating along the contact surfaces of layers. Their contribution to the final result is in most cases important enough that they should not be neglected. The main advantage of results presented in comparing to other obtained with numerical methods is their accuracy especially in the case of thin layers because all essential steps of Green's function evaluation except of the contour integration along the branch cut have been made analytically. On the other hand the disadvantage of this method is that the mathematical effort for obtaining the Green's function is increasing drastically with the increase of the number of layers. Future work will therefore be directed in simplifying of the above described process
Thin elastic plates are the basic constructional elements and are very often subjected to dynamic effects especially in the machine-building structures. Their saving design of resonance conditions of operation is an extremely complicated task which cannot be solved analytically. In the present report an efficient and sufficiently general method for optimal design of thin plates is worked out on the basis of energy resonance method of Wilder, the method of the finite elements for dynamic research and the methods of parameter optimization. By means of these methods various limitations and requirements put by the designer to the plates can be taken into account. A programme module for numerical investigation of the weight variation of the plate depending on the taken variable of the designed thickness at different supporting conditions is developed. The reasons for the considerable quantity and quality difference between the obtained optimal designs are also analysed.
In the abstract proposed is the Instrumental System of mechanics problems analysis of the deformed solid body. It supplies the researcher with the possibility to describe the input data on the object under analyses and the problem scheme based upon the variational principles within one task. The particular feature of System is possibility to describe the information concerning the object of any geometrical shape and the computation sheme according to the program defined for purpose. The Methods allow to compute the tasks with indefinite functional and indefinite geometry of the object (or the set of objects). The System provides the possibility to compute the tasks with indefinite sheme based upon the Finite Element Method (FEM). The restrictions of the System usage are therefore determined by the restrictions of the FEM itself. It contrast to other known programms using FEM (ANSYS, LS-DYNA and etc) described system possesses more universality in defining input data and choosing computational scheme. Builtin is an original Subsytem of Numerical Result Analuses. It possesses the possibility to visualise all numerical results, build the epures of the unknown variables, etc. The Subsystem is approved while solving two- and three-dimensional problems of Elasticiti and Plasticity, under the conditions of Geometrical Unlinearity. Discused are Contact Problems of Statics and Dynamics.
In this paper the results of the investigations of the free oscillations of the pre-stressed flexible structure elements are presented . Two cases of the central preliminary stress are investigated : without intermediate fastening of the tie to the flexible element and with the intermediate fastening in the middle of the element length. The given physical model can be applied to the flexible sloping shells and arches, membranes, large space antenna fields (besides flexible elements). The peculiarity of these systems is the possibility of the non-adjacent equilibrium form existence at the definite relations of the physical parameters . The transition from one stable equilibrium form to another, non-adjacent form, may be treated as jump. In this case they are called systems with buckling or the systems with two potential «gaps». These systems commenced the new section of the mathematical physics - the theory of chaos and strange attractors. The analysis of the solutions confirms the received for the first time by the author and given in effect of the oscillation period doubling of the system during the transition from the «small» oscillations relatively center to the >large< relatively all three equilibrium conditions. The character of the frequency (period) dependence on the free oscillation amplitudes of the non-linear system also confirms the received earlier result of the duality of the system behaviour : >small< oscillations possess the qualities of soft system; >large< oscillations possess the qualities of rigid system. The >small< oscillation natural frequency changing, depending on the oscillation amplitudes, is in the internal . Here the frequency takes zero value at the amplitude values Aa and Ad (or Aa and Ae ); the frequency takes maximum value at the amplitude value near point b .The >large< oscillation natural frequency changes in the interval . Here is also observed . The influence of the tie intermediate fastening doesn't introduce qualitative changes in the behaviour of the investigated system. It only increases ( four times ) the critical value of the preliminary tension force
The effectiveness of working processes accomplished by various technological machines to a large extend depends on working quality of supply, transporting and orientating mechanisms which are very often produced as positional hydro-mechanical systems. The choice of their best type and regimes of work requires construction and analysis of models of their optimum steering which are complicated by nonlinearness, multy-criterialness of problem and also by occasional outbreaks of parameters and moments of steering regime changing. It was developed the common structure of such systems allowing within common scheme to vary the complexity degree of PHMS and the methods of inhibitory efforts supplement. For some systems which are complicated in series (from two-measured linear system to nine-measured non-linear) puzzles of the most fast zero-ambit getting are solved and two-criterial problems are analyzed. (T-min-speed, Z(T)- accuracy). There are suggested the computing procedures of optimum PHMS synthesis. The effectiveness of accepted methods of solving is asserted by the analogy of the results of gradually complicated models investigation and by their good analogy with the natural experiment. It was exposed the sense of heuristic methods of improving of approximately optimum steering, their elaboration on the base of theoretical models. The basic methods of optimum PGMS construction were also nominated.
The problem of the computation of stresses and settlements in the half-space under various types of loads is often presented in geotechnical engineering. In 1885 Boussinesq advanced theoretical expressions to determine stresses at a point within an ideal mass. His equation considers a point load on the surface of a semi-infinite, homogeneous, isotropic, weightless, elastic half-space. Newmark in 1942 performed the integration of Boussinesq's equations for the vertical stress under a corner of a rectangular area loaded with a uniform load. The problem of the determination of vertical stresses under a rectangular shaped footing has been satisfactorily solved with renewal integration of the Boussinesq's equation over the arbitrary rectangle on surface of the half-space, with a non-uniform load represented with piecewise linear interpolation functions. The problem of the determination of stresses in the case when the footing shape is an arbitrary quadrilateral however remains unsolved. The paper discusses an approach to the computation of vertical stresses and settlements in an arbitrary point of the half-space, loaded with a uniform load, which shape in the ground plan can be a general four noded form with straight edges. Since the form is transformed into a biunit square and all integrations are performed over this area, all solutions are valid also for an arbitrary triangle by the implementation of the degeneration rule.
The paper analyses the influence of the effect of inertia on the reliability of production systems. Systems inertia represents the phenomenon of continuing work for some time after the breakdown of one of the former phases. In our considerations, inertia is treated as the time elapsed from the onset of breakdown till the system's inability to work. A special method had to be devised to investigate the effect of inertia in order to evaluate the reliability of production systems and to attempt algorithmization to control the reliability of production system by means of inertia or reserving. The method of reliability analysis is presented only in an inform aspect. The possibilities of increasing reliability of production systems are listed. A comparison of the redundancy method and inertia method is presented. The results of this comparison and simulated investigations of influence of inertia on reliability of system are essential scope of the paper. Selected conclusions are as follows: when inertia approaches the last phase in the system, its influence on the shape of the distribution of the system's ability increases; an increase in inertia causes an increase in the availability of the system which approaches a certain border value; dependence of the average of a system's disability on inertia has a saddle-like character whereas dependence of the number of breakdowns (stoppages) in the system has the nature of an S-curve.
Parallele Netzgenerierung
(1997)
Bei der Berechnung von statischen oder dynamischen Problemen mit Hilfe der Methode der Finiten Elemente ist eine Diskretisierung des zu berechnenden Gebietes notwendig. Bei einer sinnvollen Modellierung des Gebietes ist die Elementgröße meist nicht konstant, sondern ist an kritischen Stellen kleiner. Die Vorgaben hierfür können einerseits aus Erfahrungen des Anwenders, andererseits aus einer Fehlerabschätzung einer vorangegangenen FE-Berechnung resultieren [5]. Soll die FE-Berechnung auf einem Parallelrechner geschehen, ist eine Partitionierung des Gebietes, d.h. eine Zuordnung der Elemente zu den Prozessoren, notwendig. Bei dem hier beschriebenen Ansatz werden nun im Gegensatz zu den üblichen Verfahren erst die Eingangsdaten für den Netzgenerator umgewandelt und dann das Elementnetz direkt auf dem Parallelrecher gleichzeitig auf allen Prozessoren erzeugt. Eine Aufteilung der Elemente auf die Prozessoren entsteht als Nebenprodukt der Netzaufteilung. Die entstehenden Teilgebietsgrenzen werden geometrisch minimiert. Die Lastbalance der Netzaufteilung sowie der FE-Rechnung wird durch ein annähernd gleiche Anzahl der Elemente je Partition gewährleistet. Als Eingabedaten wird eine Beschreibung des Gebietes durch Polygonzüge, sowie einer Netzdichtefunktion, z.B. durch Punkte mit Angaben über die angestrebte Elementgröße, benötigt.
Die d - Dirac - Funktion d(x-xi) und Heviside - Funktion wurden vor allem zur Beschreibung diskontinuierlicher Belastungsfunktionen von gebogenen Balken angewendet. Im Referat werden die mathematischen Operationen auf den erwähnten Funktionen dargestellt. Darüber hinaus wird die Möglichkeit eindeutiger Aufschreibung von belibigen Belestungsfunktionen vorgeschlagen, die fast alle Fälle der in der Ingenieurpraxis auftretenden Belastungen umfassen. Die vorgeschlagenen Lösungen geben die Möglichkeit leichter Aufschreibung im Form eines Algorithmus, das die Ausnutzung von Komputertechnik in statischen Berechnungen ermöglicht. Am Ende des Referates werden die Zahlebeispiele dargestellt, die die Möglichkeiten praktischer Anwendungen der besprochenen Funktionen darstellen.
Renovation's peculiarities of industrial enterprises in conditions of economic selfsufficiency
(1997)
Probleme of recrienfation of building complex, to the sharp increase of share of reconstruction works, capital repair and modernisation of in-dustrial plants are concidered in this work. The conception of develop-ment and creation of unitified system of expluatation and renovation of industrial plants are worded out. This system is based on date-computer technology and taking into conciderations of real economic relations.
Multimodel Numerical Analysis of the Elasto-Visco-Plastic Deformation of Materials and Constructions
(1997)
At the present time there is no a generally accepted theory of visco-plasticity which is applicable for a wide class of materials and arbitrary paths of loading. The multimodel approach, based on the creation of hierarchical sequence of the models, is the most rational. The developed library of elasto-visco-plastic models includes both simplest and sophistic models demanding numerous experimental data. A unified general form of constitutive equations for all used elasto-visco-plastic models are presented based upon the concept of tensorial internal state variables. It permits to use unified algorithm of boundary tasks solution for different variants of material models. The developed selection criteria system generates the necessary conditions and provides the choice of the simplest variant of theory sufficient for correct problem solution. Formulation of the selection criteria system is based on peculiarities of viscoplastic materials behavior for the wide range thermomechanical loading and numerous computational experiments with structures different complexity levels. A set of effective schemes of integration stress-strain relations and non-linear finite element system solution are discussed for the considered class of material models. Application possibility of different material models is studied both for material element and for complicated structures. Application of the multimodel approach in numerical computations has demonstrated possibility of reliable prediction of stress-strain response under wide variety of combined loading.
The purpose of this paper is to review model for finite element techniques for non-linear crack analysis of reinforced concrete beams and slabs. The non-linear behaviour of concrete and steel were described. Some calculations of >self-stress< for concrete and reinforced concrete beam was made. Current computational aspects are discussed. Several remarks for future studies are also given. The numerical model of the concrete and reinforced concrete was described. The paper shows the results of calculations on a reinforced concrete plane stress panel with cracks. The non-linear, numerical model of calculations of reinforced concrete was assumed. Using finite elements method some calculations were made. The results of calculations like displacements, stresses and cracking are shown on diagrams. They were compared with experimental results and other finding. Some conclusions about the described model and results of calculation are shown.
Authors' own research in applied unicriterial and multicriterial optimisation of bar structures, and also an analysis of accessible bibliography on structural synthesis allows to present herein an attempt to define a general algorithm for proceeding in formulation of a structural optimisation problem. A practical aspect of such an algorithm consists, in author's opinion, in enabling a designer a correct creation of a mathematical model of synthesis problems, independently of known mathematical methods employed to looking for an unconditional extremum of function of several variables. A proposed algorithm is not a ready-for-use tool for solving all the optimisation problems, but it constitutes an easy-to-expand theoretical basis. This basis should allow a designer to create a proper set of compromises on the way to construct a mathematical model of a specific optimisation problem. The algorithm, presented in the paper, is constructed as a sequence of the one-after-another problem questions, on which the designer answers: yes or no, and a set of selections from the knowledge base consisting of the elements of an optimisation problem components. The order of making questions adopted by the authors in the algorithm is subjective, however it is supported by their experience, both in applied optimisation and in designing of structures like trusses or frames.
Der Funktionsumfang von 3D-Modellierern und die Leistung allgemein zur Verfügung stehender Rechnersysteme gestatten die Modellierung beliebiger Objekte in jeder nur denkbaren Fachdisziplin. Das potentielle Leistungsvermögen von 3D-Modellierern sollte Anreiz sein, sie so alltäglich einzusetzen, wie die etablierten Standardapplikationen. Die im Vortrag gezeigten Modelle umfassen ein kleines Spektrum der möglichen Anwendungsgebiete. Weder vom (Daten)Umfang noch von ihrem Kompliziertheitsgrad stellen sie etwas Besonderes dar. Sie sollen nur das Interesse für einen alltäglichen Einsatz von 3D-Modellierern wecken und eventuell vorhandenen Einsatzschwellen abbauen helfen. Die im Vortrag gezeigten Bildfolgen sind unter http://www.uni-weimar.de/animationen zu finden.
Der englische Physiker und Mathematiker Roger Penrose hat eine mathematische Pflasterung entdeckt, deren Formenreichtum neue Impulse in der Architektur setzen kann. In der Gemeinde Bütgenbach im Hohen Venn, Belgien, wurde das Verwaltungszentrum durch den Essener Architekten Ernst Burghartz mit mehrereren Penrose-Pflasterungen versehen. Diese beruhen auf einem Computer-Programm, welches der Vortragende zusammen mit Dr. Frank Martini entwickelt hat. Herr Burghartz hat jedoch diesen Vorentwurf nach seinen künstlerischen Vorstellungen abgewandelt.
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.
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.
In the given paper the generalized formulation of the problem of computer modelling of the complex-composite structure interaction with different types of dynamic loads and effects is discussed. Here the analysis is given as for the usage of some universal computing systems for the solution of such problems. Also if is shown that the quantification of the dynamic models of the complex-composite systems with the variable structure, depending on the character and intensivity of the effects, is necessary. The different variants of the joint and the space structure element modelling are gested. It allows to consider the complex modes of the joint bending-torsional oscillations of such structures as bridges, towers, high-rise buildings. The peculiarities of the modelling and testing of some problems of the objects aerodynamics and the interaction of the frameworks constructions with shock and movable loads are considered. In this paper the examples of the complex-composite structure dynamic analysis are shown. It is achieved by means of some special methods of the input of the real inducements and loads of the exploitated analog-object into the computing model. The suggested models found a wide use both at the design of new structures and the dynamic monitoring of the exploitated structures.
Bei der Betrachtung von Stapelproblemen ergibt sich unter anderem folgendes Problem: Ein gegebener Stapel - bestehend aus den Elementen v i der Menge V - soll an anderer Stelle in einer vorgeschriebenen, veränderten Struktur wieder aufgebaut werden. Dazu stehen Hilfsstapelplätze zur Verfügung. Die Optimierung dieses Problems hinsichtlich der Anzahl der benötigten Hilfsstapelplätze ist NP-vollständig. Es werden Erfahrungen mit einem Branch-and-Bound Algorithmus zur Lösung des Problems vorgestellt sowie ein heuristischer Algorithmus diskutiert
Gegenstand der Betrachtung ist ein spezielles Tourenproblem der Schüttgutoptimierung. Man stelle sich als Realitätsbezug ein Transportunternehmen vor, das eine Anzahl von gleichartigen Fahrzeugen in einem Fuhrpark stationiert hat. Vorgegebene Mengen von Schüttgut müssen von einer Kiesgrube zu mehreren Baustellen transportiert werden. Dabei sind Be- und Entladezeiten, unterschiedliche mittlere Geschwindigkeiten für Leer- bzw. Lastfahrten und Schichtzeiten zu berücksichtigen. Gesucht ist eine optimale Anzahl von einzusetzenden Fahrzeugen und die zugehörigen Tourenpläne mit dem Ziel der Minimierung der Transportkosten unter Beachtung der Lieferverträge. Die Lösung des Problems erfolgt in zwei Phasen. Zuerst wird die Frage geklärt, wieviele Fahrzeuge bei minimalem Kostenniveau einzusetzen und welche zu den Leerfahrten gehörigen Teilstrecken wie oft zu befahren sind. Anschließend wird mit heuristischen Verfahren versucht, die Menge der zu fahrenden Teilstrecken so auf die Fahrzeuge aufzuteilen, daß für jedes Fahrzeug eine zulässige Tour entsteht. Zur komplexen Lösung einer denkbaren Aufgabe liegt ein Programm in der Programmiersprache PASCAL vor. Die erzielten numerischen Resultate belegen, daß auch für Probleme größerer Dimension eine Optimallösung oder sehr gute Näherungen in vernünftiger Zeit gefunden werden.
Priority-rule methods for approximately minimizing the duration of a project subject to minimal and maximal time lags between the activities of the project and limited availability of renewable resources are considered. Such a project can be modelled by a cyclic activity-on-node network. Two generation schemes for constructing feasible schedules are discussed: the serial and parallel schemes. Two different kinds of heuristic procedures are proposed. The sequential or direct method processes the activities or respectively nodes of the project network one after another without considering the strong components separately. The contraction method uses a bottom-up technique. First, a feasible subschedule is determined for each strong component. Second, each strong component is replaced by a single node and the resulting acyclic network is treated by the direct method. In conclusion, some results from an experimental performance analysis of the heuristics are given using a new network generator.
We consider the standardization problem (SP) which can be formulated as follows. It is known demand bi in each type i in {1, 2, ..., n} of items. Production of yi items of the ith type brings a profit fi (yi), where fi is a nondecreasing concave function for each i in {1, 2, ..., n}.It is necessary to satisfy the demand and to maximize the total profit provided that there exist >standardization possibilities< . These possibilities means that some types of items can be replaced by some another types. We introduce generalized standardization problem (GSP) in which titems demand is given as the set of admissible demand vectors. We show that GSP and SP are special cases of the resource allocation problem over a network polymatroid. Ibasing on this observation we propose a polynomial time solution algorithm for GSP and SP.
The idea of representing urban structure and various communication systems (water and energy supply, telephone and cable TV networks) as fractal objects is not absolutely new. However, known works, devoted to this problem use models and approaches from fractal physics. For example, to simulate urban growth Diffusion Limited Aggregation (DLA) model and Dielectric Breakdown (DB) model are used. This study introduces a different approach. Net structure of communication system is described by a graph of special type called regular G(l,r,n)-graph. Authors provide description of such graph, develop iterative process for its generation and prove its self-similarity, i.e. that every regular graph is a pre-fractal. After the infinite number of steps this process generates a fractal. The devised algorithm for generation and grathical representation of regular G(l,r,n)-graphs with different values of l,r and n has been programmed to receive computer simulations. For optimal graphic presentation of pre-fractals the Optimal Space Ordering method was suggested. It is based on the minimization of the >graph energy< value about vertices' coordinates. The effective procedure for optimization was developed that takes into account specific properties of graph energy as objective function For the fractal graph introduced the Hausdorff-Besikovich and similarity dimensions were calculated. It has been shown that >graph energy< is directly related to the graph's fractal properties. For G(3,3,n) and G(4,4,n) graphs fractal dimensions calculated by different methods are the same (D=1,5 and D=2 respectively), while topological dimension of both graphs is 1.
A multicriterial statement of the above mentioned problem is presented. It differes from the classical statement of Spanning Tree problem. The quality of solution is estimated by vector objective function which contains weight criteria as well as topological criteria (degree and diameter of tree). Many real processes are not determined yet. And that is why the investigation of the stability is very important. Many errors are connected with calculations. The stability analysis of vector combinatorial problems allows to discover the value of changes in the initial data for which the optimal solution is not changed. Furthermore, the investigation of the stability allows to construct the class of the problems on base of the one problem by means of the parameter variations. Analysis of the problems with belong to this class allows to obtaine axact and adecuate discription of model
This work was partially supported by DAAD, Fundamental Researches Foundation of Belarus and International Soros Science Education Program We consider a vector discrete optimization problem on a system of non- empty subsets (trajectories) of a finite set. The vector criterion of the pro- blem consists partial criterias of the kinds MINSUM, MINMAX and MIN- MIN. The stability of eficient (Pareto optimal, Slater optimal and Smale op- timal) trajectories to perturbations of vector criterion parameters has been investigated. Suficient and necessary conditions of eficient trajectories local stability have been obtained. Lower evaluations of eficient trajectories sta- bility radii, and formulas in several cases, have been found for the case when l(inf) -norm is defined in the space of vector criterion parameters.
The theory of random matrices, or random matrix theory, RMT in what follows, has been developed at the beginning of the fties to describe the sta- tistical properties of energy levels of complex quantum systems, [1], [2], [3]. In the early eighties it has enjoyed renewed interest since it has been recognized as a very useful tool in the study of numerous physical systems. Specically, it is very useful in the analysis of chaotic quantum systems. In fact, in the last years many papers appeared about the problem of quantum chaos which implies the quantization of systems whose underlying classical dynamics is irregular (i.e. chaotic). The simplest models considered in this eld are billi- ards of various shapes. From the the classical point of view, a point particle in a 2-dimensional billiard displays regular or irregular motion depending on the shape of the billiard; for instance motion in a rectangular or circular billi- ard is regular thanks to the symmetries of the boundary. On the other hand, billiards of arbitrary shapes imply chaotic motion, i.e. exponential diver- gence of initially nearby trajectories. In order to study quantum billiards we have to consider the Schroedinger equation in various 2-dimensional domains. The eigenvalues of the Schroedinger equation represent the allowed energy levels of our quantum particle in the billiard under consideration, while the eigenfunction norms represent the probability density of nding the particle in a certain position. The question of quantum chaos is whether the charac- ter of the classical motion (regular or chaotic) can in uence some properties
With the help of functional analytical methods complex analysis is a powerful tool in treating non-linear first-order partial differential equations in the plane. Some of the most important of these equations are the Beltrami equations. This is due to the fact that the theory of Beltrami systems is related to many problems of geometry and analysis, like non-linear subsonic two-dimensional hydrodynamics, problems of conformal and quasiconformal mappings of two-dimensional Riemannian manifolds, or complex analytic dynamics. The theory of Beltrami equations is strongly connected with the -operator. This singular integral operator is immediately recognized as two-dimensional Hilbert-transform, known also under the name of integral operator with Beurling kernel, acting as an isometry of L2(C) onto L2(C). In hypercomplex function theory the Beltrami equations have not yet this importance, but nevertheless, they are a basic condition for the transfer of complex methods and efforts for solving partial differential equations, especially of non-linear type, to the spatial case. Here we deal with hypercomplex Beltrami systems. For this we restrict ourselves to the quaternionic case, but without any loss of generality. We will show how a spatial generalization of the complex -operator can be used to solve systems of non-linear partial differential equations, in particular different types of spatial Beltrami systems. Also, the for practical purposes so important norm estimates will be derived. Some of our results are stronger as known results in the complex case, but they are applicable in the complex situation, too.