TY - JOUR A1 - Guo, Hongwei A1 - Alajlan, Naif A1 - Zhuang, Xiaoying A1 - Rabczuk, Timon T1 - Physics-informed deep learning for three-dimensional transient heat transfer analysis of functionally graded materials JF - Computational Mechanics N2 - We present a physics-informed deep learning model for the transient heat transfer analysis of three-dimensional functionally graded materials (FGMs) employing a Runge–Kutta discrete time scheme. Firstly, the governing equation, associated boundary conditions and the initial condition for transient heat transfer analysis of FGMs with exponential material variations are presented. Then, the deep collocation method with the Runge–Kutta integration scheme for transient analysis is introduced. The prior physics that helps to generalize the physics-informed deep learning model is introduced by constraining the temperature variable with discrete time schemes and initial/boundary conditions. Further the fitted activation functions suitable for dynamic analysis are presented. Finally, we validate our approach through several numerical examples on FGMs with irregular shapes and a variety of boundary conditions. From numerical experiments, the predicted results with PIDL demonstrate well agreement with analytical solutions and other numerical methods in predicting of both temperature and flux distributions and can be adaptive to transient analysis of FGMs with different shapes, which can be the promising surrogate model in transient dynamic analysis. KW - Wärmeübergang KW - Deep Learning KW - Modellierung KW - physics-informed activation function KW - heat transfer KW - functionally graded materials Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20230517-63666 UR - https://link.springer.com/article/10.1007/s00466-023-02287-x VL - 2023 SP - 1 EP - 12 PB - Springer CY - Berlin ER - TY - JOUR A1 - Legatiuk, Dmitrii T1 - Mathematical Modelling by Help of Category Theory: Models and Relations between Them JF - mathematics N2 - The growing complexity of modern practical problems puts high demand on mathematical modelling. Given that various models can be used for modelling one physical phenomenon, the role of model comparison and model choice is becoming particularly important. Methods for model comparison and model choice typically used in practical applications nowadays are computationbased, and thus time consuming and computationally costly. Therefore, it is necessary to develop other approaches to working abstractly, i.e., without computations, with mathematical models. An abstract description of mathematical models can be achieved by the help of abstract mathematics, implying formalisation of models and relations between them. In this paper, a category theory-based approach to mathematical modelling is proposed. In this way, mathematical models are formalised in the language of categories, relations between the models are formally defined and several practically relevant properties are introduced on the level of categories. Finally, an illustrative example is presented, underlying how the category-theory based approach can be used in practice. Further, all constructions presented in this paper are also discussed from a modelling point of view by making explicit the link to concrete modelling scenarios. KW - Kategorientheorie KW - Modellierung KW - Modellierungsmethode KW - OA-Publikationsfonds2021 Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20210817-44844 UR - https://www.mdpi.com/2227-7390/9/16/1946?type=check_update&version=1 VL - 2021 IS - volume 9, issue 16, article 1946 PB - MDPI CY - Basel ER - TY - JOUR A1 - Legatiuk, Dmitrii A1 - Weisz-Patrault, Daniel T1 - Coupling of Complex Function Theory and Finite Element Method for Crack Propagation Through Energetic Formulation: Conformal Mapping Approach and Reduction to a Riemann–Hilbert Problem JF - Computational Methods and Function Theory N2 - In this paper we present a theoretical background for a coupled analytical–numerical approach to model a crack propagation process in two-dimensional bounded domains. The goal of the coupled analytical–numerical approach is to obtain the correct solution behaviour near the crack tip by help of the analytical solution constructed by using tools of complex function theory and couple it continuously with the finite element solution in the region far from the singularity. In this way, crack propagation could be modelled without using remeshing. Possible directions of crack growth can be calculated through the minimization of the total energy composed of the potential energy and the dissipated energy based on the energy release rate. Within this setting, an analytical solution of a mixed boundary value problem based on complex analysis and conformal mapping techniques is presented in a circular region containing an arbitrary crack path. More precisely, the linear elastic problem is transformed into a Riemann–Hilbert problem in the unit disk for holomorphic functions. Utilising advantages of the analytical solution in the region near the crack tip, the total energy could be evaluated within short computation times for various crack kink angles and lengths leading to a potentially efficient way of computing the minimization procedure. To this end, the paper presents a general strategy of the new coupled approach for crack propagation modelling. Additionally, we also discuss obstacles in the way of practical realisation of this strategy. KW - Angewandte Mathematik KW - Finite-Elemente-Methode KW - Rissausbreitung KW - Modellierung KW - Bruchmechanik KW - fracture mechanics KW - crack propagation KW - coupling KW - energetic approach Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20210805-44763 UR - https://link.springer.com/article/10.1007/s40315-021-00403-7 VL - 2021 SP - 1 EP - 23 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Gürlebeck, Klaus A1 - Legatiuk, Dmitrii A1 - Nilsson, Henrik A1 - Smarsly, Kay T1 - Conceptual modelling: Towards detecting modelling errors in engineering applications JF - Mathematical Methods in Applied Sciences N2 - Rapid advancements of modern technologies put high demands on mathematical modelling of engineering systems. Typically, systems are no longer “simple” objects, but rather coupled systems involving multiphysics phenomena, the modelling of which involves coupling of models that describe different phenomena. After constructing a mathematical model, it is essential to analyse the correctness of the coupled models and to detect modelling errors compromising the final modelling result. Broadly, there are two classes of modelling errors: (a) errors related to abstract modelling, eg, conceptual errors concerning the coherence of a model as a whole and (b) errors related to concrete modelling or instance modelling, eg, questions of approximation quality and implementation. Instance modelling errors, on the one hand, are relatively well understood. Abstract modelling errors, on the other, are not appropriately addressed by modern modelling methodologies. The aim of this paper is to initiate a discussion on abstract approaches and their usability for mathematical modelling of engineering systems with the goal of making it possible to catch conceptual modelling errors early and automatically by computer assistant tools. To that end, we argue that it is necessary to identify and employ suitable mathematical abstractions to capture an accurate conceptual description of the process of modelling engineering systems. KW - Angewandte Mathematik KW - Angewandte Informatik KW - Ingenieurwissenschaften KW - Modellierung KW - engineering KW - abstraction KW - modelling KW - formal approaches KW - type theory Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20200110-40614 UR - https://onlinelibrary.wiley.com/doi/abs/10.1002/mma.5934 SP - 1 EP - 10 ER - TY - JOUR A1 - Chubukov, A. A1 - Kapitanov, Valeriy A1 - Monina, Olga A1 - Silyanov, Valentin A1 - Brannolte, Ulrich T1 - Simulation of Regional Mortality Rate in Road Accidents JF - Transportation Research Procedia 20 N2 - The paper gives the results of scientific research, which, being based on probabilistic and statistical modeling, identifies the relationship of certain socio-economic factors and the number of people killed in road accidents in the Russian Federation regions. It notes the identity of processes in various fields, in which there is loss of life. Scientific methods and techniques were used in the process of data processing and study findings: systematic approach, methods of system analysis (algorithmization, mathematical programming) and mathematical statistics. The scientific novelty lies in the formulation, formalization and solving problems related to the analysis of regional road traffic accidents, its modeling taking into account the factors of socio-economic impact. KW - Modellierung KW - correlation; factors; loss of life in accidents; modeling; Road traffic accidents; socio-economic aspect; statistical analysis Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170331-30956 UR - http://www.sciencedirect.com/science/article/pii/S2352146517300315 SP - 112 EP - 124 ER - TY - JOUR A1 - Zhuang, Xiaoying A1 - Huang, Runqiu A1 - Liang, Chao A1 - Rabczuk, Timon T1 - A coupled thermo-hydro-mechanical model of jointed hard rock for compressed air energy storage JF - Mathematical Problems in Engineering N2 - 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. KW - Energiespeicherung KW - Druckluft KW - Kaverne KW - Modellierung Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170428-31726 ER - TY - JOUR A1 - Kreibich, H. A1 - Piroth, K. A1 - Seifert, I. A1 - Maiwald, Holger A1 - Kunert, U. A1 - Schwarz, Jochen A1 - Merz, B. A1 - Thieken, A. H. T1 - Is flow velocity a significant parameter in flood damage modelling? JF - Natural Hazards and Earth System Science N2 - Flow velocity is generally presumed to influence flood damage. However, this influence is hardly quantified and virtually no damage models take it into account. Therefore, the influences of flow velocity, water depth and combinations of these two impact parameters on various types of flood damage were investigated in five communities affected by the Elbe catchment flood in Germany in 2002. 2-D hydraulic models with high to medium spatial resolutions were used to calculate the impact parameters at the sites in which damage occurred. A significant influence of flow velocity on structural damage, particularly on roads, could be shown in contrast to a minor influence on monetary losses and business interruption. Forecasts of structural damage to road infrastructure should be based on flow velocity alone. The energy head is suggested as a suitable flood impact parameter for reliable forecasting of structural damage to residential buildings above a critical impact level of 2m of energy head or water depth. However, general consideration of flow velocity in flood damage modelling, particularly for estimating monetary loss, cannot be recommended. KW - Strömungsgeschwindigkeit KW - Überschwemmung KW - Schaden KW - Modellierung Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170425-31455 UR - http://www.nat-hazards-earth-syst-sci.net/9/1679/2009/nhess-9-1679-2009.pdf SP - 1679 EP - 1692 ER - TY - JOUR A1 - Kiviniemi, Arto A1 - Fischer, Martin T1 - Requirements Management Interface to Building Product Models N2 - In current AEC practice client requirements are typically recorded in a building program, which, depending on the building type, covers various aspects from the overall goals, activities and spatial needs to very detailed material and condition requirements. This documentation is used as the starting point of the design process, but as the design progresses, it is usually left aside and changes are made incrementally based on the previous design solution. These incremental small changes can lead to a solution that may no longer meet the original requirements. In addition, design is by nature an iterative process and the proposed solutions often also cause evolution in the client requirements. However, the requirements documentation is usually not updated accordingly. Finding the latest updates and evolution of the requirements from the documentation is very difficult, if not impossible. This process can lead to an end result, which is significantly different from the documented requirements. Some important requirements may not be satisfied, and even if the design process was based on agreed-upon changes in the scope and requirements, differences in the requirements documents and in the completed building can lead to well-justified doubts about the quality of the design and construction process... KW - Produktmodell KW - Simulation KW - Bautechnik KW - Bauwerk KW - Modellierung Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-2427 ER - TY - JOUR A1 - Fink, Thomas T1 - Structural analysis, design and detailing using standard CAD software and standard building information model N2 - This paper describes the concept of a german commercial software package developed for the needs of structural engineers. Using a standard CAD software as user interface for all geometrical data and to save all important input data, there is a natural link to upcoming building information models. KW - Bauindustrie KW - CAD KW - Bauwerk KW - Modellierung Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-2702 ER - TY - JOUR A1 - Staub-French, Sheryl T1 - Feature-based Product Modeling for Building Construction N2 - Current building product models explicitly represent components, attributes of components, and relationships between components. These designer-focused product models, however, do not represent many of the design conditions that are important for construction, such as component similarity, uniformity, and penetrations. Current design and construction tools offer limited support for detecting these construction-specific design conditions. This paper describes the ontology we developed using the manufacturing concept of features to represent the design conditions that are important for construction. The feature ontology provides the blueprint for the additions and changes needed to transform a standard product model into a constructionspecific product model. The ontology formalizes three classes of features, defines the attributes and functions of each feature type, and represents the relationships between features explicitly. The descriptive semantics of the ontology allows practitioners to represent their varied preferences for naming features, specifying features that result from component intersections and the similarity of components, and grouping features that affect a specific construction domain. A software prototype that implements the ontology enables practitioners to transform designer-focused product models into feature-based product models that represent the construction perspective. KW - Produktmodell KW - Simulation KW - Bautechnik KW - Baukonstruktion KW - Modellierung Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-2331 ER - TY - JOUR A1 - Wehner, R. A1 - Steinmann, Frank A1 - Hübler, Reinhard T1 - FLEXOB - Entwicklungstool für dynamische, modellbasierte CAD-Systeme N2 - Objektorientierte Modellierungstechniken werden gegenwärtig vor allem Entwicklern von CAD-Systemen angeboten. Sie erzeugen über die Schritte OO-Modellanalyse und OO-Softwaredesign OO-Programme, die mit ihrer Compilation das durch den Softwareingenieur gefundene Modell festschreiben. Generell, aber insbesondere im Bauwerksdesign, ist dieses Vorgehen unbefriedigend, da hier eine Normung von Modellen nicht gelingt, der Entwurfsprozeß vergleichsweise lang ist und eine Kooperation von Ingenieurgewerken mit verschiedenen Modelldomänen die Regel sind. Darüber hinaus weisen die Modelle in frühen Phasen ein hohes Maß an Unschärfe und Abstraktion auf. CAD-Tools, die diese Phasen unterstützen, benötigen deshalb: statt eines genormten Produktmodells ein einheitliches, kognitiv begründetes Modellstrukturierungsparadigma, für das mit der Objektorientierung eine mögliche Ausprägung gegeben ist, ein explizites, verfügbares Domänenmodell zur fortwährenden Interpretation von Bauwerksmodellen, deskriptive Elemente, die die Interpretation von Objekten und Attributen erleichtern, ein Konzept zur Behandlung von Unschärfe und Abstraktion. Hieraus ergeben sich für die Entwicklung von CAD-Systemen folgende Forderungen : Explizite Verfügbarkeit von Klassenobjekten und deren Erzeugung und Veränderung zur Laufzeit, Vererbung auf Klassen- und Instanzniveau, Erweiterte Attributkonzepte (Facetten), Unterstützung der Aggregation als einer wesentlichen Modellstrukturierungsrelation, Verfügbarkeit von OO-Schnittstellen zum Aufbau von CAD-Systemen aus Tools einerseits, sowie zur Trennung von Modellverwaltung und Modellrepräsentation andererseits. Als ein herausragendes Merkmal des Objektorientierten Paradigmas wird die Anwendungsnähe genannt, da Erscheinungen der behandelten Domäne sich analog in Modellen und Programmen wiederfinden (sollen). Unter der Grundannahme, daß dieses Paradigma auch durch den Anwender zur Erstellung seiner Modellwelten verwendet wird, will FLEXOB eine homogene Umgebung schaffen, die die Modellwelt des Softwareingenieurs zu Analysezwecken dem Anwender zur Verfügung stellt und die die Erweiterung dieser Modellwelt auf deskriptivem Niveau ermöglicht. Das Tool FLEXOB und einige wesentliche Implementationsdetails werden im Beitrag vorgestellt. Es handelt sich bei diesem Tools um eine C++ Klassenbibliothek, die entweder als Objektmodul oder als Windows-DLL verwendet werden kann. Aspekte des Nutzungsregimes solch flexibler Modellverwaltungen werden im Beitrag ebenfalls angespochen. KW - CAD KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-4571 ER - TY - JOUR A1 - Minch, M. J. A1 - Trochanowski, A. T1 - The numerical Modelling and Analysis of RC cracked Structures N2 - 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. KW - Tragwerk KW - Stahlbeton KW - Rissbildung KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-5278 ER - TY - JOUR A1 - Rebolj, D. T1 - A Product Model of a Road N2 - Many errors and delays frequently appear when data is exchanged between particular tasks in the lifecycle of the road. Inter-task connections are therefore of great importance for the quality of the final product. The article describes a product model of a road wich is the kernel of an integrated information system intended to support all important stages of the road lifecycle: design, evaluation (through different analysis procedures), construction, and maintainance. Since particular tasks are often executed at different places and in different companies, the interconnections are supported by a special metafile which contains all specific data of the product model. The concept of the integrated system is object and component oriented. Additionally, existing conventional program packages are included to support some common tasks (methods). A conventional relational database system as well as an open spatial database system with the relevant GIS functionality are included to support the data structures of the model. KW - Straße KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-4584 ER - TY - JOUR A1 - Fischer, A. A1 - Steinhage, V. T1 - Ein modellbasiertes Konzept zur städteplanerischen Kartierung durch digitale Bildanalyse N2 - There is an increasing need for 3D building extraction from aerial images for various applications such astown planning, environmental- and property-related studies. Aerial images usually reveal on one hand a certain amount of information not relevant for the given task of building extraction like vegetation, cars etc. On the other hand there is a loss of relevant information due to occlusions, low contrasts or disadvantageous perspectives. Therefore a promising concept for automated building reconstruction must incorporate a suffciantly complete model of the objects of interest. We propose a model-based approach to 3D building extraction from aerial images which reveals a tight coupling between a generic 3D object model and an explicit 2D image model. The generic object model employes domain specific volumetric primitives (i. e. building part models) and combination schemes. To cover the gap between 3D object models and 2D image data the image model is employed to predict the projective building appearences in aerial images. We present a strategy for a model-based building extraction based on the recognition-by-components principle and show first experimental results derived from international test sets KW - Stadtplanung KW - Kartierung KW - Bildanalyse KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-4870 ER - TY - JOUR A1 - Steinmann, Frank A1 - Hübler, Reinhard T1 - Vorgehensmodelle als Basis der Gestaltung durchgaengiger CAD-Systeme N2 - Für die Gestaltung einer durchgängigen Unterstützung des Entwurfsprozesses stehen gegenwärtig deskriptive Modelle der Entwurfsobjekte im Mittelpunkt der Untersuchungen. Diese Modelle gestatten das Ableiten von Repräsentationen sowie eine Weitergabe von Entwurfsergebnissen. Pragmatische Gliederungen des Entwurfsprozesses unterteilen diesen nach organisatorischen und betriebswirtschaftlichen Aspekten (Planbarkeit und Abrechenbarkeit) in eine Sequenz von Entwurfsphasen (HOAI). Diese Gliederungen berücksichtigen nicht das WIE des eigentlichen modellkreierenden Schaffensprozesses. Für ein echtes CADesign bildet dessen Klärung jedoch die erforderliche Voraussetzung. Im Beitrag wird dazu von einem vereinheitlichten Set generischer Entwurfsaktionen ausgegangen. Auch dann, wenn die verschiedenen Entwurfsphasen und die Entwurfshandlungen der einzelnen Ingenieurgewerke mit spezifische Entwurfsmodellen verbunden werden, besteht damit eine Grundlage zur methodischen Fundierung entsprechender CAD-Tools. Die methodische Verfahrensweise ähnelt der, die in Form von Styleguides zur Gestaltung von 'Graphical User Interfaces' vorgeschlagen wird. Wesentliche praktische Benutzungen solche Basisaktivitäten ergeben sich für: die Systematisierung computergestützter Entwurfshandlungen, insbesondere durch Erweiterung des deskriptiven um ein operationales Modell sowie deren erweiterte Interpretierbarkeit die Erzeugung wissensbasierter Werkzeuge zur automatischen Modellgenerierung/-konfiguration die Implementation von leistungsfähigen UNDO- bzw. TMS-Mechanismen. KW - CAD KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-4568 ER - TY - JOUR A1 - Piskunov, V. G. A1 - Marchuk, A. V. T1 - Model of stressed-strained State of Multilayer Masses with regard for Non-Ideal Contact of Layers N2 - 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. KW - Geschichtetes Medium KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-5427 ER - TY - JOUR A1 - Kazakevitch, M. I. A1 - Kulyabko, V. V. A1 - Dubichvost, A. A. T1 - The discrete dynamic Models of the Interaction of complex - composite Structures with the dynamic Loads N2 - 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. KW - Verbundtragwerk KW - Dynamische Belastung KW - Wechselwirkung KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-5219 ER - TY - JOUR A1 - Rudnicki, Andrzej T1 - Investigation by Computer Simulation - some aspect of transportation service reliability in urban public transport N2 - Essence of service unreliability on account of irregularity has been given. The reasons of occurance of overcrowded vehicles have been listed. The factor of service unreliability on account of irregularity has been determined. It is probability of the event, that the passenger finds departing vehicle fully filled, i.e. when all places seating and standing are occupied or condition of the travel, which would be not acceptable for passenger. Large dispersion of headways (i.e. irregularity) increases probability of such situations. To calculate the mentioned factor, the computer simulation was used. Both, passenger arrivals and vehicle operation have been modelled as stochastic interacted processes. Distributions of headways and passenger arrivals have been fixed by statistical methods. The >maximal capacity< of a vehicle has been determined. The set of parameters values for simulation runs has been given. The transformed results of computer simulation are series of nomographs for determination of a factor value. They were prepared for many types of trams and city buses, but only one nomograph has been presented. Difficulties in verification of model were discussed. Recommendations for rational utilisation level of public transport means capacity in the condition of randomness of passenger arrivals and disturbances in vehicle operation have been proposed. The other possibilities of service unreliability have been mentioned. General conclusions have been given KW - Öffentlicher Personennahverkehr KW - Zuverlässigkeit KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-4829 ER - TY - JOUR A1 - Zhak, S. V. A1 - Sidorenko, V. S. T1 - Optimized Models of Modes Choice for Displacement of technical Systems Objects N2 - 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. KW - Modellierung KW - Optimierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-5347 ER - TY - JOUR A1 - Dudek, Mariusz T1 - Modellierung der Verkehrsmittelwahl N2 - Die Zielstellung der Modal­Split­Betrachtungen läuft darauf hinaus, Entscheidungs-kriterien zu erarbeiten, nach denen die einzelnen Personen ihre Verkehrsmittel auswählen. In dieser Veröffentlichung wurden alle drei Gruppen der Modelle (klassische, verhaltensorientierte und der Analyse) der Verkehrsaufteilung kurz charakterisiert. Dann wurden vier ausgewählte Modelle genauer beschrieben. Zum Schluß wird das Modell der Verkehrsmittelwahl dargestellt , das für die Untersuchung der Verkehrsaufteilung in Krakau verwendet wurde . KW - Verkehrsmittelwahl KW - Modellierung Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20111215-4817 ER -