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Journal articles on the topic "Plates (Engineering) Testing Mathematical models":
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Stara, Marie. "Testing of Pre-Stressing Masonry Wall with Using Different Thickness of Anchor Plates." Advanced Materials Research 1082 (December 2014): 211–15. http://dx.doi.org/10.4028/www.scientific.net/amr.1082.211.
Contribution deals with experimental measurements of deformations in the place exposed to local load caused by additional pre-stressing. The measurements are made at the masonry brick corner built in the laboratory equipment. The laboratory equipment was designed at Faculty of Civil Engineering VŠB – TU Ostrava for measurement tri-axial stress-strain conditions in masonry. In this brick corner one pre-stressing bar is placed. And on the pre-stressing bar is anchored to the anchor plate which transfer pre-stressing forces to the masonry. The thickness of brick corner is 440mm and anchor plate will be used about thickness 10, 20 and 30mm. Mathematical modelling of brick corner is based on finite element method using software ANSYS and then the results are compared with results of laboratory tests. On the basis of these results it should be possible to improve the models and to approach closer to the accurate and at the same time simple procedure for design of pre-stressed masonry.
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Borkovic, Aleksandar, Dragan Milasinovic, Valentina Golubovic-Bugarski, Ognjen Mijatovic, and Manuel Desancic. "Experimental and numerical identification of structural modes for engineering education." Facta universitatis - series: Architecture and Civil Engineering 12, no. 2 (2014): 161–72. http://dx.doi.org/10.2298/fuace1402161b.
Development of simple classroom demonstration device and software for visualization of structural normal modes is presented. Device is made of parts of old speaker, controlled with personal computer, where the harmonic motion of solenoid is used as an excitation for beam and plate models. Simple code for finite element free vibration analysis of plates is written in Wolfram Mathematica. Good agreement of results and attractive visual patterns of normal modes attracted attention of students. Results are confirmed using modern modal testing methods. Presented approach is complementary to standard teaching of structural dynamics.
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Gharababaei, H., N. Nariman-zadeh, and A. Darvizeh. "A Simple Modelling Method for Deflection of Circular Plates Under Impulsive Loading using Dimensionless Analysis and Singular value Decomposition." Journal of Mechanics 26, no. 3 (September 2010): 355–61. http://dx.doi.org/10.1017/s1727719100003919.
AbstractA novel approach of numerical modelling using input-output experimental data pairs is presented for deflection-thickness ratio of circular plates subjected to impulse loading. In this way, singular value decomposition (SVD) method is used in conjunction with dimensionless parameters incorporated in such complex process. The closed-form obtained model shows very good agreement with some testing experimental data pairs which have been unforeseen during the training process. Moreover, two modifications are consequently suggested for some similar models already proposed in previous works. The approach of this paper can generally be applied to model very complex real-world processes using appropriate experimental data.
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Vorobyov, V. S., E. L. Karelina, O. A. Bender, and K. V. Katalymova. "STATISTICAL MODELS OF PHYSIC-MECHANICAL CHARACTERISTICS OF ROADS IN THE AREA OF CULVERTS." Vestnik SibADI 15, no. 4 (September 12, 2018): 560–73. http://dx.doi.org/10.26518/2071-7296-2018-4-560-573.
Introduction. Increased technical requirements for roads, associated with increasing axial loads, the intensity and speed of vehicles, with the actual technical condition of the roads number, engineering structures, including culverts, activation of federal and regional services to bring the parameters of road surfaces to the world standards, all listed parameters pose the task in developing the mathematical modeling methods of physical-mechanical characteristics of soils in the culverts area. Therefore, such methods allow to reduce economic costs and time for carrying out experimental research of deformations based on the monitoring results of the soil roadbed and pavement.Materials and methods. The order of technical condition of the culverts’ research, pavement and physico-mechanical characteristics of soils, methods of experimental research were discussed in the article. Moreover, the approach to carrying out experimental works on penetration of pits in places of deformations and nearby was approved. Additionally, the evaluation of the soils condition on the roadbed and the annular space of the culverts was made.Results. The schemes of deformation and elasticity, density, humidity, consistency, plasticity number, fluidity, and physical properties of the soil are determined. The engineering-geological elements, mean values of density, humidity and compaction factor are established according to the research aim. Consequently, the values of the strain modules and the modulus of elasticity are calculated on the basis of compression and stamp tests.Discussion and conclusions. The dependence of the pavement on the physic-mechanical characteristics of the soil of the roadbed is proved. The correlation-regression analysis of soil characteristics is performed on the basis of experimental research. As a result, the regression equations are obtained in the annular space of culverts and at the distance of ± 30 m nearby. As could be proved, there are irregularities in the coverage of road clothes caused by drawdown in barrier locations. The physic-mechanical characteristics of the ground and strength characteristics are increased by culverts’ transfer on distance. The application of physic-mechanical characteristics of the soil together with experimental studies makes it possible to reduce labor costs, time and cost of testing.
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Al-Kannoon, Muslim Abdul-Ameer, and Hayder Wafi AL-Thabhawee. "Investigation of flexural and shear failure modes of tapered castellated steel beams using expansion plates." Eastern-European Journal of Enterprise Technologies 4, no. 7 (118) (August 30, 2022): 6–13. http://dx.doi.org/10.15587/1729-4061.2022.262558.
Using modern technologies for fabricating steel, I-beams can be easily made by welding, and hot-rolled beams can often be produced at an economical price with slender webs and equal flanges. Experimental and theoretical studies of the behavior of tapered castellated steel beams were carried out. Due to the cost reductions associated with tapered castellated steel beams, they are a feasible alternative to prismatic components. This study assessed the influence of tapered castellation on the bending capacity and flexural stiffness of tapered castellated steel beams (TCBs) with simply supported end conditions experimentally and theoretically. Four three-point bending tests on TCBs with H/h values of 1, 1.2, 1.4 and 1.6 were conducted utilizing a standard parent I-section beam (IPE140) as the control specimen. The test findings include the ultimate load vs. mid-span deflection response curves and failure mechanisms. The testing findings indicated that the TCBs' ultimate load capacity might be up to 140 percent of that of the parent section. The Abaqus program was used to conduct a finite element (FE) analysis of TCB, which allows for material and geometric nonlinearity. The derived finite element models exhibit excellent agreement with the experimental results in terms of ultimate load capacity vs. mid-span deflection response and failure mechanisms. Based on the results of the work, TCBs can be used for increasing the strength and stiffness of the I-section parent beam with adding expansion plates. The maximum load capacity of TCBs can be enhanced when adding expansion plates up to 40 % above that of the parent beam. A TCB has lower ductility than its parent beam. Moreover, a TCB fulfills serviceability requirements since its mid-span depth exceeds that of its parent beam.
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GIORGI, C. "Mathematical models of thin thermoviscoelastic plates." Quarterly Journal of Mechanics and Applied Mathematics 53, no. 3 (September 1, 2000): 363–74. http://dx.doi.org/10.1093/qjmam/53.3.363.
Kyvelou, Pinelopi, David A. Nethercot, Nicolas Hadjipantelis, Constantinos Kyprianou, and Leroy Gardner. "The Evolving Basis for the Design of Light Gauge Steel Systems." International Journal of Structural Stability and Dynamics 20, no. 13 (October 10, 2020): 2041008. http://dx.doi.org/10.1142/s0219455420410084.
The importance of allowing for the many different types of structural interaction that have an effect on the performance of light gauge members when used in practical situations is emphasized. A distinction is drawn between internal interactions involving the various plate elements of the steel profiles and external interactions involving the other components in the system. Although full-scale testing of representative systems can capture this behavior, the costs involved make this an impractical general basis for design; codified methods generally consider only isolated plates within members and isolated members within systems, thereby neglecting the potentially beneficial effects of both forms of interaction. Properly used, modern methods of numerical analysis offer the potential to systematically allow for both forms of interaction — provided the numerical models used have been adequately validated against suitable tests. The use of such an approach is explained and illustrated for three commonly used structural systems: roof purlins, floor beams, and columns in stud walls. In each case, it is shown that, provided sufficient care is taken, the numerical approach can yield accurate predictions of the observed test behavior. The subsequently generated large portfolio of numerical results can then provide clear insights into the exact nature of the various interactions and, thus, form the basis for more realistic design approaches that are both more accurate in their predictions and which lead to more economic designs. Building on this, modifying existing arrangements so as to yield superior performance through specific modifications is now possible. Two such examples, one in which improved interconnection between the components in a system is investigated and a second in which prestressing is shown to provide substantial enhancement for relatively small and simple changes, are presented.
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Kostyleva, Liliya Yu, Oleg V. Loginovskiy, Evgeniya A. Retc, and Igor M. Yachikov. "Possibilities of using mathematical models for thermal nondestructive testing of defects in multilayer bimetallic plates." Bulletin of the South Ural State University. Ser. Computer Technologies, Automatic Control & Radioelectronics 22, no. 1 (January 2022): 53–64. http://dx.doi.org/10.14529/ctcr220104.
There is an actual task of delamination detection in multilayer bimetallic materials. Various methods of nondestructive testing (NDT) are used to solve it, including the method of transient thermal NDT. This method consists in remote registration, visualization and analysis of thermal (temperature) fields, which depend on thermophysical and geometric characteristics, thermal effect capacity and internal structure features of the object. The internal structure defects cause the appearance of abnormal temperature zones on the object surface. Their analysis allows us to judge the presence of changes in the material as a whole or in individual areas. It is possible to understand whether there is a defect under the anomalous site, and what its parameters are, if there is an adequate mathematical model that theoretically describes the dependence of the measuring results on the properties of the object and the selected technological modes. This model is a significant component of thermal NDT systems. For the same object or process, a certain set of mathematical models can be compiled, differing in the number of factors taken into account, the assumptions made, the completeness and accuracy of the description of the state of the object or the conditions of the process. The set of factors is determined by the purpose of the study, and in order to unambiguously determine the model of the thermal state, it is necessary to describe the characteristics of the object (geometric shape and thermophysical characteristics of the material) and the heat exchange process (characteristics of heat sources, initial and boundary conditions). Aim. To analyze the existing mathematical models for the research object – a multilayer bimetallic plate with delaminations between the outer and inner layers, and to identify common approaches to modeling the processes of thermal NDT of multilayer objects. Materials and methods. The structure of the mathematical model of the thermal state of the object is determined. An analytical review of mathematical models of thermal NDT of multilayer objects is performed. Results. The requirements, assumptions and limitations for a mathematical model of thermal NDT of a multilayer bimetallic plate with delamination defects are formulated. Conclusion. On the basis of the considered approaches to the mathematical modeling of the thermal state of multilayer objects with ideal layers contact and delamination defects, the necessary factors for the development of a model for the transient thermal NDT processes of the studied objects are determined.
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Prysiazhnyi, Andrii H., Volodymyr V. Kukhar, Vadym Hornostai, Ekaterina Kudinova, Maryna Korenko, and Oleksandr S. Anishchenko. "Mathematical Models for Forecasting of 10Mn2VNb Steel Heavy Plates Mechanical Properties." Materials Science Forum 1045 (September 6, 2021): 237–45. http://dx.doi.org/10.4028/www.scientific.net/msf.1045.237.
The problem urgency for determining the optimal rolling and heat treatment schedules for providing the required indices of heavy plates physical and mechanical properties is shown. The use of statistical mathematical models for solving this problem is substantiated and the methodology for their design is described. Statistical mathematical models were designed using the mathematical statistics methods and Data Mining tools to determine the yield strength, ultimate tensile strength and percent elongation for 10Mn2VNb steel plates rolled under 3600 heavy plate mill conditions. Software for the numerical implementation of these statistical mathematical models has been developed. Applied software has been developed for the numerical implementation of the statistical mathematical models for predicting the heavy plate’s mechanical properties, and high calculation accuracy has been confirmed with the ones help: 95.82% for the yield strength, 96.78% for the ultimate tensile strength, and 91.48% for the percent elongation. The regularities of the influence for finish rolling factual temperature in the finishing stand of 3600 heavy plate mill and the plate thickness on 10Mn2VNb pipe steel physical and mechanical properties were identified by processing the database and using the designed software.
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Feinberg, Alec. "Accelerated Reliability Growth Models." Journal of the IEST 37, no. 1 (January 1, 1994): 17–23. http://dx.doi.org/10.17764/jiet.2.37.1.f2u73m8022207868.
Extending reliability growth so that it can be applied in the area of accelerated testing will enable one to apply all the reliability growth tools and their planning advantages. This paper describes linking these two areas together into what is termed accelerated reliability growth testing (ARGT). Mathematical equations of ARGT for both iso-stress and step-stress accelerated testing are modelled.
You might also be interested in the extended bibliographies on the topic 'Plates (Engineering) Testing Mathematical models' for particular source types:
Dissertations / Theses on the topic "Plates (Engineering) Testing Mathematical models":
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Reddy, Yeruva S. "Numerical simulation of damage and progressive failures in composite laminates using the layerwise plate theory." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/38534.
Akileh, Aiman R. "Elastic-plastic analysis of axisymmetrically loaded isotropic circular and annular plates undergoing large deflections." PDXScholar, 1986. https://pdxscholar.library.pdx.edu/open_access_etds/3559.
The concept of load analogy is used in the elastic and elastic-plastic analysis of isotropic circular and annular plates undergoing moderately large deflection. The effects of the nonlinear terms of lateral displacement and the plastic strains are considered as additional fictitious lateral loads, edge moments, and in-plane forces acting on the plate. The solution of an elastic or elastic-plastic Von Karman type plate is hence reduced to a set of two equivalent elastic plate problems with small displacements, namely, a plane problem in elasticity and a linear elastic plate bending problem. The method of finite element is employed to solve the plane stress problem. The large deflection solutions are then obtained by utilizing the solutions of the linear bending problems through an iterative numerical scheme. The flow theory of plasticity incorporating a Von Mises layer yield criterion and the Prandtl-Reuss associated flow rule for strain hardening materials is employed in this approach.
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Banan, Roshan Aerospace Civil & Mechanical Engineering Australian Defence Force Academy UNSW. "An engineering approach to modelling ballistic impact on hybrid polymer laminates." Publisher:University of New South Wales - Australian Defence Force Academy. Information Technology & Electrical Engineering, 2009. http://handle.unsw.edu.au/1959.4/44094.
Hybrid polymer laminates of polycarbonate and PMMA have generated considerable interest among researchers as an alternative to traditional glass armours because of their potential for reduced cost and weight. Generally, the development of ballistic armour is carried out experimentally which is an expensive task in terms of time and cost. Numerical simulation provides a much greater facility to understand the phenomenon of ballistic impact and the effects of various parameters on the response to such impact. In addition it provides an easy means of comparing the impact performance of different materials as well as combination of materials forming hybrid laminates. The aim of this research was to develop a numerical modelling capability to simulate the ballistic response of hybrid polymer laminates, specifically polycarbonate and PMMA, using a commercially available finite element code LS-DYNA. The challenge was to work within the limitations of the material models and the failure algorithms available within LS-DYNA, and still try to reproduce the behaviour observed experimentally by previous researchers, initially on monolithic plates of polycarbonate and PMMA and then on hybrid laminates. The first part of the study focuses on a detailed literature survey on mechanical and dynamic characterisation of polycarbonate and PMMA as well as experimental and numerical studies previously conducted on ballistic behaviour of these materials as well as their combinations. The material properties of the polymers compiled from this literature survey were used as input for the selected LS-DYNA material model. Impact simulations were carried on monolithic and laminated media of polycarbonate and PMMA and where possible these were compared to experimental results. It was observed that the results agreed with the experimental data qualitatively. Quantitatively the results showed some discrepancies which were attributed to the limitations faced in simulating the exact test conditions numerically. Numerical simulations were carried out to study the effects of variations in laminate thickness and plate support diameters as well as to examine the influence of the bond between the layers. Finally the impact response of four different combinations of polycarbonate and PMMA are compared to each other for different laminate thicknesses.
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Young, Andrew J. "Active control of vibration in stiffened structures." Title page, contents and abstract only, 1995. http://hdl.handle.net/2440/37722.
Active control of vibration in structures has been investigated by an increasing number of researchers in recent years. There has been a great deal of theoretical work and some experiment examining the use of point forces for vibration control, and more recently, the use of thin piezoelectric crystals laminated to the surfaces of structures. However, control by point forces is impractical, requiring large reaction masses, and the forces generated by laminated piezoelectric crystals are not sufficient to control vibration in large and heavy structures. The control of flexural vibrations in stiffened structures using piezoceramic stack actuators placed between stiffener flanges and the structure is examined theoretically and experimentally in this thesis. Used in this way, piezoceramic actuators are capable of developing much higher forces than laminated piezoelectric crystals, and no reaction mass is required. This thesis aims to show the feasibility of active vibration control using piezoceramic actuators and angle stiffeners in a variety of fundamental structures. The work is divided into three parts. In the first, the simple case of a single actuator used to control vibration in a beam is examined. In the second, vibration in stiffened plates is controlled using multiple actuators, and in the third, the control of vibration in a ring-stiffened cylinder is investigated. In each section, the classical equations of motion are used to develop theoretical models describing the vibration of the structures with and without active vibration control. The effects of the angle stiffener(s) are included in the analysis. The models are used to establish the quantitative effects of variation in frequency, the location of control source(s) and the location of the error sensor(s) on the achievable attenuation and the control forces required for optimal control. Comparison is also made between the results for the cases with multiple control sources driven by the same signal and with multiple independently driven control sources. Both finite and semi-finite structures are examined to enable comparison between the results for travelling waves and standing waves in each of the three structure types. This thesis attempts to provide physical explanations for all the observed variations in achievable attenuation and control force(s) with varied frequency, control source location and error sensor location. The analysis of the simpler cases aids in interpreting the results for the more complicated cases. Experimental results are given to demonstrate the accuracy of the theoretical models in each section. Trials are performed on a stiffened beam with a single control source and a single error sensor, a stiffened plate with three control sources and a line of error sensors and a ring-stiffened cylinder with six control sources and a ring of error sensors. The experimental results are compared with theory for each structure for the two cases with and without active vibration control. Thesis (Ph.D.)--Mechanical Engineering, 1995.
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Liu, Bing 1975. "FE analysis of plastic buckling of plates with initial imperfections and simulation of experiments." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100251.
The general problem of plastic buckling of flat metal plates is a fundamental area of investigation in mechanics not only because of its intrinsic importance in the design of engineering structures, but also because it still has not been settled in a satisfying manner. Which theory of plasticity is the correct one to predict the buckling loads in the plastic range is a long-argued problem. This thesis presents finite element analyses of plastic buckling and postbuckling behaviour of columns and plates, taking into account the presence of initial out-of-plane imperfections. The FE programs constructed by the author for this purpose are used to analyze the imperfection growth of such columns and plates under axial loading and simply supported edge conditions. The material behaviour is modeled according to both the incremental and the deformation theories of strain-hardening plasticity. The programs combine both the geometric and material nonlinearities to trace the load-deflection behaviours of these structures in prebuckling (up to the maximum load) as well as postbuckling ranges. The results of the analyses for plates show the extreme sensitivity of the incremental theory, and the relative insensitivity of the deformation theory, to the initial imperfections. The programs are used to simulate the plastic buckling experiments on Aluminum tubes, taking into account their measured imperfections. The imperfection growth analyses demonstrate that the maximum load predictions of the incremental theory are quite close to those recorded in the experiments.
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Robbins, Donald H. "Hierarchical modeling of laminated composite plates using variable kinematic finite elements and mesh superposition." Diss., Virginia Tech, 1993. http://hdl.handle.net/10919/40117.
The strength and behavior of gusset plates in buckling is evaluated herein based on data from the experimental investigations conducted by other researchers and the analytical work presented herein. A set of design guidelines has been recommended through the review of the current practice. Representative single and double brace gusset plates normally adopted for connections with compressive bracing/diagonal members in braced frames and trusses, were modeled and analyzed using linear and nonlinear finite element methods to determine the buckling loads. The buckling analysis data along with the test data indicated the occurrence of inelastic buckling of the gusset plates. Current design practice and a set of formulas for determination of gusset plate thickness have been reviewed. A set of guidelines has been recommended for the design and evaluating gusset plate buckling loads.
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Abel, Mary Sue M. "Four-bolt extended unstiffened moment end-plate connections." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-11242009-020221/.
Current manufacturing research aims at increasing productivity by optimal selection of process parameters. This is accomplished by understanding the fundamental physics of individual manufacturing processes.
In this thesis, peripheral milling of very flexible cantilevered plates is studied. The static and dynamic deflections of the plate under periodic milling forces are modelled. A new dynamic cutting force model is developed which considers five discrete zones of relative motion between the tool and the workpiece. The kinematics of both milling and vibratory motions are modelled, which is an original research contribution in this area. It is shown that the penetration of the tool into the workpiece during vibratory cutting has a strong influence on the damping and stiffness characteristics of the milling process.
A structural model of a discontinuous cantilevered plate is determined using the finite element method. A reduced order structural model at the tool-workpiece contact zone is implemented for discrete time response analysis of the plate under cutting force excitations during milling. The closed loop dynamic behaviour of the system is modelled and taken into account in the analysis. Simulations of plate machining are compared with experimental results. A model of the surface finish generation mechanism is deduced from the analysis and experimental results.
Applications of this research include peripheral milling of integral jet engine impellers, computer disk drives and other flexible mechanical components. Applied Science, Faculty of Mechanical Engineering, Department of Graduate
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張啓軍 and Qijun Zhang. "The Galerkin Element Method and power flow in acoustic-structural problems with damped sandwich plates." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31239742.
Constanda, C. A mathematical analysis of bending of plates with transverse shear deformation. Harlow, Essex, England: Longman Scientific & Technical, 1990.
Book chapters on the topic "Plates (Engineering) Testing Mathematical models":
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Xu, Xaiojian, and Wan Yi Huang. "Optimal Robust Designs of Step-Stress Accelerated Life Testing Experiments for Proportional Hazards Models." In Mathematical and Computational Approaches in Advancing Modern Science and Engineering, 585–94. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30379-6_53.
Broy, Manfred, Wolfgang Böhm, and Bernhard Rumpe. "Advanced Systems Engineering." In Model-Based Engineering of Collaborative Embedded Systems, 353–64. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-62136-0_19.
AbstractAdvanced systems engineering (ASE) is a new paradigm for agile, efficient, evolutionary, and quality-aware development of complex cyber-physical systems using modern digital technologies and tools. ASE is essentially enabled by smart digital modeling tools for specifying, modeling, testing, simulating, and analyzing the system under development embedded in a coherent and consistent methodology.The German Federal Ministry of Education and Research (BMBF) projects SPES2020, SPES_XT, and CrESt offer such a methodology and framework for model-based systems engineering (MBSE). The framework provides a comprehensive methodology for MBSE that is independent of tools and modeling languages. The framework also offers a comprehensive set of concrete modeling techniques and activities that build on a formal, mathematical foundation. The SPES framework is based on four principles that are of paramount importance: (1) Functional as well as non-functional requirements fully modeled and understood at system level. (2) Consistent consideration of interfaces at each system level. (3) Decomposition of systems into subsystems and their interfaces. (4) Models for a variety of cross-sectional topics (e.g., variability, safety, dynamics).
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Matei, Alexander, and Stefan Ulbrich. "Detection of Model Uncertainty in the Dynamic Linear-Elastic Model of Vibrations in a Truss." In Lecture Notes in Mechanical Engineering, 281–95. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77256-7_22.
AbstractDynamic processes have always been of profound interest for scientists and engineers alike. Often, the mathematical models used to describe and predict time-variant phenomena are uncertain in the sense that governing relations between model parameters, state variables and the time domain are incomplete. In this paper we adopt a recently proposed algorithm for the detection of model uncertainty and apply it to dynamic models. This algorithm combines parameter estimation, optimum experimental design and classical hypothesis testing within a probabilistic frequentist framework. The best setup of an experiment is defined by optimal sensor positions and optimal input configurations which both are the solution of a PDE-constrained optimization problem. The data collected by this optimized experiment then leads to variance-minimal parameter estimates. We develop efficient adjoint-based methods to solve this optimization problem with SQP-type solvers. The crucial test which a model has to pass is conducted over the claimed true values of the model parameters which are estimated from pairwise distinct data sets. For this hypothesis test, we divide the data into k equally-sized parts and follow a k-fold cross-validation procedure. We demonstrate the usefulness of our approach in simulated experiments with a vibrating linear-elastic truss.
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"iOS App and Architecture of Convolutional Neural Networks." In Advances in Computer and Electrical Engineering, 1–22. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1554-9.ch001.
Deep convolutional neural networks (CNN) have attracted many attentions of researchers in the field of artificial intelligence. Based on several well-known architectures, more researchers and designers have joined the field of applying deep learning and devising a large number of CNNs for processing datasets of interesting. Equipped with modern audio, video, screen-touching components, and other sensors for online pattern recognition, the iOS mobile devices provide developers and users friendly testing and powerful computing environments. This chapter introduces the trend of developing pattern recognition CNN Apps on iOS devices and the neural organization of convolutional neural networks. Deep learning in Matlab and executing CNN models on iOS devices are introduced following the motivation of combining mathematical modelling and computation with neural architectures for developing pattern recognition iOS apps. This chapter also gives contexts of discussing typical hidden layers in the CNN architecture.
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Monge, Peter R., and Noshir Contractor. "Computational Modeling of Networks." In Theories of Communication Networks. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195160369.003.0010.
Computer simulations have long been used as an effective tool in engineering, economics, psychology, and a number of other social sciences. Engineers typically use simulations to predict performance of a system that has known dynamic characteristics. These characteristics are typically obtained from theory and are then articulated in the simulation as difference or differential equations. The goal of engineering simulation is then to assess the dynamic performance of a system based on a priori knowledge of the dynamic relationships among the various elements of the system. Forrester (1961, 1973) was one of the earliest and most influential advocates of simulation modeling of dynamic social systems. Forrester advocated this approach as a way to model and assess the dynamics of industrial and world phenomena. Sterman (2000) provides a recent review of research on dynamics simulation from this tradition. While this approach has produced a considerable number of studies, it too is based on the assumption that the researcher has a priori knowledge of the dynamic relationships among elements of the system. Indeed, many of the results of these models have been criticized for specifying relationships that were at best untested and at worst flawed. In response to these criticisms, more recent interest has focused on redefining the utility of simulations in the social sciences. Rather than using simulations to test the long-term dynamics of systems with known interrelationships, theorists (Carley & Prietula, 1994; Contractor, 1994; Hanneman, 1988) have suggested that social scientists should use simulations to help construct theory, to identify the heretofore-unknown interrelationships. This section describes the traditional use of computer simulations as well as the adaptation of this approach toward theory construction and testing in the social sciences. Later sections will apply these general approaches to the computational modeling of networks in particular. Carley and Prietula (1994) suggest that the emergence of the new field of computational organizational theory (COT) signals the growing interest in the construction of computational models to augment and assist theory building. Most social science theories are richly evocative but highly abbreviated (Poole, 1997), that is, they offer explanations that suggest complex interrelationships but do not provide precise, falsifiable mathematical formalizations of the theory.
Conference papers on the topic "Plates (Engineering) Testing Mathematical models":
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Koliskina, Valentina, and Andrei Kolyshkin. "Mathematical model for eddy current testing of metal plates with two cylindrical flaws." In 2015 IEEE 15th International Conference on Environment and Electrical Engineering (EEEIC). IEEE, 2015. http://dx.doi.org/10.1109/eeeic.2015.7165190.
Ericson, Tristan M., and Robert G. Parker. "Planetary Gear Modal Properties and Dynamic Response: Experiments and Analytical Simulation." In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-47142.
Planetary gear vibration is a major source of noise and may lead to fatigue-induced failures in bearings or other drivetrain components. Gear designers use mathematical models to analyze potential designs, but these models remain unverified by experimental data. This paper presents experiments that completely characterize the dynamic behavior of a spur planetary gear by modal testing and spinning tests under representative operating conditions, focusing on the independent motion of planetary components. Accelerometers are mounted directly to individual gear bodies. Rotational and translational accelerations obtained from the experiments are compared to the predictions of a lumped parameter model. Natural frequencies, modes, and forced response agree well between experiments and the model. Rotational, translational, and planet mode types presented in published analytical research are observed experimentally.
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Marshall, Rob, and Paul F. Altamore. "Mathematical Model Methodology to Compare Different Occupant Models in Frontal Impact." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/amd-25443.
Abstract Restraint system and vehicle design rely heavily on the use of Anthropomorphic Test Devices and mathematical models of ATD’s to provide information about human occupant response in impact conditions. Recent advances in ATD’s take years to get through the prototyping and evaluation stages before they can be widely used. The recent advances in ATD development will not benefit the testing of many vehicles for quite some time. The development of mathematical models of new ATD’s that are not yet available for widespread use, as well as mathematical models of humans can provide more information about human occupant responses to engineers. This study develops a method to utilize these mathematical models in combination with a highly detailed vehicle model to gain more understanding of how human occupants will behave in a frontal impact.
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Senjanović, Ivo, Nikola Vladimir, Dae-Seung Cho, and Tae-Muk Choi. "Vibration Analysis of Thick Plates: Analytical and Numerical Approaches." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23273.
In this paper an examination of methods for vibration analysis of moderately thick rectangular plates has been presented. First, the state-of-the art in thick plate vibration theories and analysis methods is described and it is followed with basic equations of the original Mindlin theory, which represents a starting point for the development of all other mathematical models. Then, the problem of analytical solving of equilibrium equations is considered based on the modified Mindlin theory of thick plate vibrations, which has been published in the literature recently. Further, energy methods that can be applied to arbitrary boundary conditions are discussed and outline of the assumed mode method is presented. Finally, in the context of numerical methods a new quadrilateral finite element, based on the above mentioned advanced thick plate theory, is included. It should be emphasized that it doesn’t suffers of shear locking problem associated with finite elements, due to natural relation among bending and shear polynomials, and moreover, it gives very accurate results. Application of the presented methods is illustrated by several numerical examples which include natural vibration analyses of rectangular plates with various thicknesses and different combinations of boundary conditions (simply supported, clamped, free and elastically restrained). Comparisons of natural frequencies and mode shapes with results available in the relevant literature and with those obtained by the commercial finite element software are also provided.
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Ferrari, Giovanni, Marco Amabili, and Prabakaran Balasubramanian. "Nonlinear Damping on Large-Amplitude Vibrations of Plates." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50951.
Large-amplitude (geometrically nonlinear) forced vibrations of completely free sandwich and steel rectangular plates are investigated experimentally. Harmonic excitation is applied by using an electro-dynamic exciter and the plate vibration is measured by using laser Doppler vibrometers. A scanning laser Doppler vibrometer is used for experimental modal analysis since it provides non-contact vibration measurements with very high spatial resolution. The large-amplitude vibration experiments are carried out by using a single point Laser Doppler Vibrometer and a stepped-sine testing procedure. The non-linear frequency response curves are obtained by increasing and decreasing the excitation frequency in very small steps at specific force amplitudes controlled in a closed-loop. The experimental results are compared to numerical simulations obtained by reduced-order models and show very good agreement. The nonlinear damping is experimentally obtained as a function of the vibration amplitude.
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Hudson, Mary L., Richard Kottenstette, Carolyn M. Matzke, Greg C. Frye-Mason, Kim A. Shollenberger, Doug R. Adkins, and C. Channy Wong. "Design, Testing, and Simulation of Microscale Gas Chromatography Columns." In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-1244.
Abstract A microscale gas chromatography column is one component in a microscale chemistry laboratory for detecting chemical agents. Several columns were fabricated using the Bosch etch process which allows deep, high aspect ratio channels of rectangular cross-section. A design tool, based on analytical models, was developed to evaluate the effects of operating conditions and column specifications on separation resolution and time. The effects of slip flow, channel configuration, and cross-sectional shape were included to evaluate the differences between conventional round, straight columns and the microscale rectangular, spiral columns. Experimental data were obtained and compared with the predicted flowrates and theoretical number of plates. The design tool was then employed to select more optimum channel dimensions and operating conditions for high resolution separations.
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Baghdasaryan, Lusine, Wei Chen, Thaweepat Buranathiti, and Jian Cao. "Model Validation via Uncertainty Propagation Using Response Surface Models." In ASME 2002 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/detc2002/dac-34140.
Model validation has become a primary means to evaluate accuracy and reliability of computational simulations in engineering design. Mathematical models enable engineers to establish what the most likely response of a system is. However, despite the enormous power of computational models, uncertainty is inevitable in all model-based engineering design problems, due to the variation in the physical system itself, or lack of knowledge, and the use of assumptions by model builders. Therefore, realistic mathematical models should contemplate uncertainties. Due to the uncertainties, the assessment of the validity of a modeling approach must be conducted based on stochastic measurements to provide designers with the confidence of using a model. In this paper, a generic model validation methodology via uncertainty propagation is presented. The approach reduces the number of physical testing at each design setting to one by shifting the evaluation effort to uncertainty propagation of the computational model. Response surface methodology is used to create metamodels as less costly approximations of simulation models for uncertainty propagation. The methodology is illustrated with the examination of the validity of a finite-element analysis model for predicting springback angles in a sample flanging process.
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Khulief, Y. A., and F. A. Al-Sulaiman. "Experimentally-Tuned Mathematical Model for Drillstring Vibrations." In ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-35057.
Field experience manifests that drillstring vibration is one of the major causes for a deteriorated drilling performance. It is crucial to understand the complex vibrational mechanisms experienced by a drilling system in order to better control its functional operation and improve its performance. Experimental studies of drillstring dynamics are essential to complement the theoretical studies, and to alleviate the complexity of such dynamic models. This paper presents an experimental investigation using a specially designed drilling test rig. The test rig can simulate the drillstring vibrational response due to various excitation mechanisms, which include stick-slip, well-borehole contact, and drilling fluid interaction. The test rig is driven by a variable speed motor which allows for testing different drilling speeds, while a magnetic tension brake is used to simulated stick-slip. In addition, a shaker is employed to excite the drillstring axially in order to simulate the weight-on-bit (WOB). The drillstring is instrumented for vibration measurements. The experimentally identified parameters are used to refine the finite element multibody model of the drillstring, which was derived earlier by the investigators [1]. Comparisons with published data demonstrate the reliability of the developed scheme for prediction of drillstring vibrations.
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Liu, Chia-Chang, and Kao Hui Lin. "Simulation of Double Flank Gear Rolling Testing." In ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-86970.
The double flank gear rolling testing is a method by which a master gear is rolled together, in tight mesh, with a testing gear. As the gears roll, slight variations of center distance are measured and recorded as an indicator of gear quality. The double flank gear rolling testing is easy and low coast, therefore, it is widely used in gear industry. In this study, the mathematical models of standard master gears and testing gears with various errors are carried out first according to the theory of gearing. Then, the process of double flank gear rolling testing is simulated by applying the concept of tooth contact analysis (TCA). Tooth contact types including surface-to-surface contact and tip-to-surface interference are considered, and three possible combinations of these two contact types occurring on each tooth flanks are discussed as well. The results of this study can provide the industry a significant process to establish the analysis and capacities for double flank testing.
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Myo Thant, Maung Maung, M. Faizal Che Daud, Siti Nur Shaffee, Kien Kiet Chua, Antti Nissinen, Jouni Kartikainen, Pasi Laakkonen, and Alan Ong Li. "Acceleration of New Technology Qualification and Deployment for Sand Level Measurement in Production Vessels." In International Petroleum Technology Conference. IPTC, 2021. http://dx.doi.org/10.2523/iptc-21186-ms.
Abstract Measurement of sand build-up in the production separators has been a challenge for field personnel due to the limitations of current technologies. Nucleonic-type level profiler has been previously implemented in a few offshore locations but limited due to special handling and permit/license requirements of radioactive material involved. Therefore, this paper aims to present the acceleration of new non-nucleonic tomographic technology testing and qualification to measure accumulating sand in separators as well as multi-disciplinary approvals for fast-track field application. The general idea in tomography is to expose the target of interest to electrical signals and measure the response of the target. With the aid of mathematical models, it is possible to infer the distribution of different materials within the target from the responses. Results of tomographic measurements are displayed on a computer as a vertical profile. The tested tomographic solution was based on a tomographic technology called Electrical Tomography. The key idea in Electrical Tomographic image construction is to find a permittivity and conductivity distribution for which the observations predicted by the model are in good agreement with actual ET measurement data and hence profiling is to be created. The test was performed at the laboratory with a full tomographic profiler setup including a test probe sensor for profiling, electronics, and a computer unit. In addition to the tomographic instrumentation, a transparent plastic vessel was used for visual observations of the accumulated sand layers. Visual observations were made simultaneously with tomographic imaging. In the test setup, we had sand, water, emulsion, and oil. The samples were placed into a transparent vessel. It was visually observed that the probe sensor was able to distinguish "wet sand-water" interface and "water-oil interface" in all the tested conditions. At the end of the test, the sand layer was flattened and packed more tightly and the change in the layer thickness was seen in the tomographic image. We concluded that the resolution of the detection of the sand layer was in the range of 1-2 cm. The technology is novel as it is a non-nucleonic profiler and a field-safe technology to be used. The profiler is intrinsically safe and certified to the most demanding IECEx class to be used in Zone 0 hazardous atmospheres. Detailed engineering of the technology to be installed at one of the production separators has proceeded. Finite Element Analysis has shown that the system can withstand turbulent conditions within the multi-phase production separator.
