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Abstract

The automotive industry is characterized by a high degree of uncertainty. Companies are facing the challenge of producing different systems simultaneously. Additionally, the global quantity of electric vehicles is also expected to increase significantly. This results in the following capability to remain competitive: Effective and efficient adaptions of production systems to model variations and volume increases. While flexible production is identified as the most promising concept, defining the actual flexibility level of included production resources is essential for its proper realization. A literature review on existing flexibility assessment approaches revealed their emphasis on high-level enablers and limited practical applicability in the automotive industry. In contrast, focusing the assessment on single workstations supports the selection of appropriate production resources. Therefore, a simple and structured standard procedure for a production resource flexibility assessment was developed. This theoretical construct was subsequently complemented with practical insights through its application on two real-life case studies within one automotive engineering company. Summarizing and discussing the findings in combination with a conclusion completed this paper.
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Authors and Affiliations

Oliver Moerth-Teo
1
Gernot Schlögl
2
Muaaz Abdul-Hadi
3
Markus Brillinger
3
Martin Weinzerl
4
Christian Ramsauer
1

  1. Institue of Innovation and Industrial Management, Graz University of Technology, Austria
  2. Institue of Production Engineering, Graz University of Technology, Austria
  3. Pro2Future GmbH, Austria
  4. AVL List GmbH, Austria
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Abstract

The article presents an overview of polymeric materials for flexible substrates in photovoltaic (PV) structures that could be used as power supply in the personal electronic systems. Four types of polymers have been elected for testing. The first two are the most specialized and heat resistant polyimide films. The third material is transparent polyethylene terephthalate film from the group of polyesters which was proposed as a cheap and commercially available substrate for the technology of photovoltaic cells in a superstrate configuration. The last selected polymeric material is a polysiloxane, which meets the criteria of high elasticity, is temperature resistant and it is also characterized by relatively high transparency in the visible light range. For themost promising of these materials additional studies were performed in order to select those of them which represent the best optical, mechanical and temperature parameters according to their usage for flexible substrates in solar cells.

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Authors and Affiliations

K. Znajdek
Maciej Sibiński
ORCID: ORCID
A. Strąkowska
Z. Lisik
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Abstract

The aim of the study is to compare flexible pavement design lifespans and the main factors which create their values for a standard structure and one with an anti-fatigue course AF at different parameter values of pavement and its load, relevant to their design processes. Depending on the mixture used for the anti-fatigue course or the course thickness, durability improvement of the pavement (compared to the durability of a standard structure) can be obtained by extending the design lifespan of the asphalt base course or by extending the design lifespan of the AF course. On sections with predominantly slow traffic, the lifespan decreases significantly compared to sections with typical vehicle speed – the relative decrease is greater if anti-fatigue course is applied.

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Authors and Affiliations

M. Nagórska
R. Nagórski
K. Błażejowski
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Abstract

The awareness of the growing importance of the complexity in creating a new type of a modern enterprise strategy and in introducing changes within planning, control and organizational structures contributed to undertaking studies on relationships occurring between the complexity of a modern enterprise and its flexibility in the sector of industrial automation, as well as filling the gap relating to the cognitive impact of poor complexity management on the flexibility of the company. The main objective of the research work is to check whether there is an important relationship between the complexity of the business and its flexibility in the industrial automation sector. Quantification of the relationship between these two quantities – the complexity and flexibility – happened by the use of the Multidimensional Correspondence Analysis (MCA) and Perceptual Maps. The study which has been carried out indicated that the flexibility and complexity functions in the enterprise management rise, however, the knowledge of these issues is highly insufficient. The research discovered that the obstacles which hamper striking a balance between the flexibility and complexity in their advanced stages exert a devastating impact on the quality of the process management. Reducing the flexibility at its higher levels generates a context in which the market risk is enhanced. Companies characterised by improper flexibility management bear higher workforce costs and their processes of decision-making last longer. Methodical and systematized study of flexibility and complexity will decrease the destructive influence of the interaction between these two categories.

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Authors and Affiliations

A. Lewandowska-Ciszek
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Abstract

Developing novel methods, approaches and computational techniques is essential for solving efficiently more and more demanding up-to-date engineering problems. Designing durable, light and eco-friendly structures starts at the conceptual stage, where new efficient design and optimization tools need to be implemented. Nowadays, apart from the traditional gradient-based methods applied to optimal structural and material design, innovative techniques based on versatile heuristic concepts, like for example Cellular Automata, are implemented. Cellular Automata are built to represent mechanical systems where the special local update rules are implemented to mimic the performance of complex systems. This paper presents a novel concept of flexible Cellular Automata rules and their implementation into topology optimization process. Despite a few decades of development, topology optimization still remains one of the most important research fields within the area of structural and material design. One can notice novel ideas and formulations as well as new fields of their implementation. What stimulates that progress is that the researcher community continuously works on innovative and efficient topology optimization methods and algorithms. The proposed algorithm combined with an efficient analysis system ANSYS offers a fast convergence of the topology generation process and allows obtaining well-defined final topologies.
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Authors and Affiliations

Katarzyna Tajs-Zielińska
1
Bogdan Bochenek
1

  1. Faculty of Mechanical Engineering, Cracow University of Technology, Al. Jana Pawła II 37, 31-864 Kraków, Poland
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Abstract

Understanding and measuring mental well-being among adolescents has recently become a priority. The validity and reliability study of the 7-item short version of the Warwick Edinburgh Mental Well-Being Scale (SWEMWBS) has not been examined in Turkish adolescents. Therefore, this study aims to adapt the 7-item Warwick Edinburgh Mental Well-Being Scale to Turkish and examine the relationships between loneliness, emotional flexibility, resilience, and mental well-being. The data were collected by convenience sampling method from 820 adolescents aged 14-18 from 73 city of Turkey. During the adaptation process of SWEMWBS, confirmatory factor analysis, concurrent validity, and reliability analysis were performed. The findings confirmed the one dimensionality of the 7-item scale on the Turkish adolescent sample. In addition, a significant positive relationship was found between mental well-being and emotional flexibility and resilience. However, there was a significant negative correlation between mental well-being and loneliness. The results showed that the Turkish version of SWEMWBS had strong psychometric properties in adolescents.
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Authors and Affiliations

Yakup İme
1

  1. Necmettin Erbakan University, Konya-Turkey, Turkey
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Abstract

The paper is devoted to the description of the methodology and research by design carried out to identify solutions enhancing the functional flexibility of a high-rise building located in Warsaw at. Grzybowska Street. The work presents the theoretical background as well as the conducted research and methodology. The scope of solutions related to functional flexibility concerned the interchangeability of service functions in the podium part of the building, changes in the use of the parking lot, and the provision of the means of changes in the arrangement of types and variants of types of apartments on the apartments levels. The investigation was carried out in the pre-design and design phases. Objectives and criteria of solutions were defined, and research works were carried out through iterations and checking in terms of the cost-effectiveness . The adopted solutions consist in designing the optimal hard portion of the building – the core, the structural system, the arrangement of zones and installation rooms, and the use of structural and spatial over-designed systems. An optimal facade module has been developed. The research aims to introduce the design practice to the issue of flexibility, which is nowadays important for economic and environmental reasons.
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Authors and Affiliations

Marcin Goncikowski
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Architecture, ul. Koszykowa 55, 00-659 Warsaw, Poland
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Abstract

The article concerns modern, flexible adhesive joints, which might be used in timber construction. The article discusses the test results carried out for timber elements joints using polymeric adhesives produced by Sika®. The scope of the tests includes the analysis of strength criteria, tests of polymer adhesion to the timber with a pull-off method, tests of polymer layer shearing between timber elements as well as examination of bending of timber elements joined with polymer. The conclusions indicate the types of these polymers which are recommended for the creation of polymeric joints of timber-polymeric type in timber constructions.

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Authors and Affiliations

Klaudia Śliwa-Wieczorek
Bogusław Zając
Tomasz Kozik
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Abstract

The technical requirements for the determination of physical parameters of vibration isolating material have not been standardized in Europe and Poland yet, which significantly hinders the ability to compare vibration isolating materials offered on the market. Therefore, there is a need for establishing a norm that could be applied both for the determination of the physico-mechanical properties of elastic vibration isolation elements in rail transport for domestic and foreign producers as well as in their selection for application in a specific vibration isolation system. The paper presents a proposal to standardize the methodology of the estimation of vibration isolation materials physical parameters authorized for use in vibration isolation systems used in rail transport. Methodology for measuring the physico-mechanical parameters of vibration isolating material presented in the paper forms uniform test procedure developed based on a fragmentary norms for flexible materials testing. The use of the proposed research methodology enables the creation of a unified database of elastic materials which parameters will be easy to compare, and choice between them will become easier for designers of vibration isolation systems used in rail transport.

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Authors and Affiliations

Jarosław Bednarz
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Abstract

In the present work, a tire model is derived based on geometrically exact shells. The discretization is done with the help of isoparametric quadrilateral finite elements. The interpolation is performed with bilinear Lagrangian polynomials for the midsurface as well as for the director field. As time stepping method for the resulting differential algebraic equation a backward differentiation formula is chosen. A multilayer material model for geometrically exact shells is introduced, to describe the anisotropic behavior of the tire material. To handle the interaction with a rigid road surface, a unilateral frictional contact formulation is introduced. Therein a special surface to surface contact element is developed, which rebuilds the shape of the tire.

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Authors and Affiliations

Michael Roller
Peter Betsch
Axel Gallrein
Joachim Linn
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Abstract

Wave-Based Control has been previously applied successfully to simple underactuated flexible mechanical systems. Spacecraft and rockets with structural flexibility and sloshing are examples of such systems but have added difficulties due to nonuniform structure, external disturbing forces and non-ideal actuators and sensors. The aim of this paper is to extend the application of WBC to spacecraft systems, to compare the performance of WBC to other popular controllers and to carry out experimental validation of the designed control laws. A mathematical model is developed for an upper stage accelerating rocket moving in a single plane. Fuel sloshing is represented by an equivalent mechanical pendulum model. A wave-based controller is designed for the upper stage AVUM of the European launcher Vega. In numerical simulations the controller successfully suppresses the sloshing motion. A major advantage of the strategy is that no measurement of the pendulum states (sloshing motion) is required.

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Authors and Affiliations

Joseph William Thompson
William O’Connor
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Abstract

Flexible, slender structures like cables, hoses or wires can be described by the geometrically exact Cosserat rod theory. Due to their complex multilayer structure, consisting of various materials, viscoplastic behavior has to be expected for cables under load. Classical experiments like uniaxial tension, torsion or three-point bending already show that the behavior of e.g. electric cables is viscoplastic. A suitable constitutive law for the observed load case is crucial for a realistic simulation of the deformation of a component. Consequently, this contribution aims at a viscoplastic constitutive law formulated in the terms of sectional quantities of Cosserat rods. Since the loading of cables in applications is in most cases not represented by these mostly uniaxial classical experiments, but rather multiaxial, new experiments for cables have to be designed. They have to illustrate viscoplastic effects, enable access to (viscoplastic) material parameters and account for coupling effects between different deformation modes. This work focuses on the design of such experiments.

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Authors and Affiliations

Vanessa Dörlich
Joachim Linn
Tobias Scheffer
Stefan Diebels
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Abstract

To study the impact of suspended equipment on the ride comfort in a railway vehicle, a rigid flexible general model of such a vehicle is required. The numerical simulations is based on two different models, derived from the general model of the vehicle, namely a reference model of a vehicle with no equipment, and another model with six suspended elements of equipment mounted in various positions along the carbody. The objective of this paper arises from the observation that the literature does not contain any study that highlights the change in the ride comfort resulting exclusively due to the influence of equipment. The influence of the suspended equipment on the ride comfort is determined by comparing the ride comfort indices calculated in the carbody reference points, at the centre and above the two bogies, for a model with six elements of equipment and a model of the vehicle with no equipment.

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Authors and Affiliations

Mădălina Dumitriu
1

  1. Department of Railway Vehicles, University Politehnica of Bucharest, Bucharest, Romania
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Abstract

The main aim of the article is to develop a simulation model of flexible manufacturing

system with applying the ontology on flexibility. Designing manufacturing systems matching

both production and market requirements becomes more and more challenging due to the

variability of demand for a large number of products made in many variants and short

lead times. Manufacturing flexibility is widely recognised as a proven solution to achieve

and maintain both the strategical and operational goals of the companies exposed to global

competition. Generic simulation model of flexible manufacturing system was developed using

FlexSimr 3D software, then the example data were used to demonstrate the developed model

applicability. “The Ontology on Flexibility” was applied for evaluation of achieved flexibility

of manufacturing system.

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Authors and Affiliations

Sławomir Luscinski
Vitalii Ivanov
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Abstract

The paper presents a dynamic analysis of the damaged masonry building repaired with the Flexible Joint Method. Numerical analysis helped to determine the effect of the applied repairing method on natural frequencies as well as values of stresses and accelerations in the analyzed variants of numerical model. They confirmed efficiency of the proposed repair method.

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Authors and Affiliations

A. Kwiecień
P. Kuboń
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Abstract

In the present study, we analyse the influence of goal maintenance and goal change on the efficiency of executive control. Although there is empirical evidence on the impact of goal maintenance and task-switching on executive control, little is known about the consequences of changing between processing goals (e.g., speed or accuracy goals). We assessed the influence of changing between speed and accuracy goals while performing a task-switching procedure that requires social categorization. Experiment 1 included frequent goal changes, whereas Experiment 2 included one goal change across the experimental session. The results showed that both goals influence general performance and flexibility. A comparison between experiments suggested that frequent goal change (Experiment 1) resulted in worse performance and lower flexibility overall, compared to sequential goal change (Experiment 2). Frequent goal change was also associated with increased difficulties in pursuing the accuracy goal. The implications regarding the role of goal maintenance and goal change on executive control are discussed, as well as new research possibilities.
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Authors and Affiliations

Sofía Castro
1
Marcin Bukowski
1
Juan Lupiáñez
2
Zofia Wodniecka
1

  1. Institute of Psychology, Jagiellonian University, Kraków, Poland
  2. Department of Experimental Psychology, and Mind, Brain and Behavior Research Center (CIMCYC), University of Granada, Granada, Spain
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Abstract

The article presents the results of numerical and analytical investigations of the influence of raw liquid natural gas (LNG) composition on parameters characterizing the combustion process. The high content of higher hydrocarbons influences the thermodynamic combustion process described with parameters like the adiabatic flame temperature, laminar flame speed and ignition delay time. A numerical study of the impact of LNG fuels on emission characteristics using the Cantera code has been performed. Results have shown that the change of grid natural gas to some types of liquid natural gas can result in an incomplete combustion process and an increase of emission of toxic compounds such as carbon monoxide and unburned hydrocarbons. For all investigated fuels the laminar flame speed rises by about 10% compared to natural gas, while the adiabatic flame temperature is nearly the same. The ignition delay time is decreased with an increase of ethane share in the fuel. The analysis of chemical pathways has shown that hydrogen cyanide and hydrogen formation is present, particularly in the high temperature combustion regimes, which results in an increase of nitric oxide molar fraction in flue gases by even 10% compared to natural gas. To summarize, for some applications, liquid natural gases cannot be directly used as interchangeable fuels in an industry sector, even if they meet the legal requirements.
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Authors and Affiliations

Paweł Czyżewski
1
Rafał Ślefarski
1
Joanna Jójka
1

  1. Poznan University of Technology, Institute of Thermal Energy, Piotrowo 3a, 60-965, Poznan, Poland
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Abstract

Many variants of thin film technology are nowadays part of the photovoltaic market. The most popular are amorphous silicon, CIS (Copper Indium Selenide)/CIGS (Copper Indium Gallium Selenide)/CIGSS (Copper Indium Gallium Sulphur Selenide), and CdS/CdTe (Cadmium Sulphide/Cadmium-Telluride) cells. All mentioned types allow potentially for a flexible cell structure. Most emitter contacts are currently based on TCOs (Transparent Conductive Oxides), however, wider approach with alternative carbon nanoforms, silver nanolayers and polymer materials, called TCLs (Transparent Conductive Layers) are also in use. Authors decided to investigate influence of mechanical stresses on physical and electrical behaviour of these layers. Consequently, the aim of work is to determine the level and possible mechanisms of flexible a-Si cell parameters degradation due to a deterioration of transparent contact properties.

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Authors and Affiliations

Maciej Sibiński
ORCID: ORCID
K. Znajdek
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Abstract

The paper describes a research on assessing the quality of edges resulting from the interaction of laser pulses with a material of rigid and flexible printed circuits. A modern Nd:YVO4 crystal diode-pumped solid-state laser generating a 532 nm wavelength radiation with a nanosecond pulse time was used for the research. Influence of laser parameters such as beam power and pulse repetition frequency on a heat affected zone and carbonization was investigated. Quality and morphology of laser-cut substrates were analyzed by optical microscopy. High quality laser cutting of printed circuit board substrates was obtained without delamination and surface damage, with a minimal carbonization and heat affected zone. The developed process was implemented on the printed circuit assembly line.

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Authors and Affiliations

P. Ciszewski
M. Sochacki
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Abstract

This paper presents a study of the hybrid electro-discharge mechanical machining BEDMM (Brush Electro-Discharge Mechanical Machining) with the application of a rotary disk brush as a working electrode. The discussed method enables not only an effective machining with a material removal rate of up to 300 mm3/min but also finishing (with the obtained roughness of Ra < 0.5 μm) of the surfaces of complex-shaped alloys with poor machinability. The analysis of the factors involved in the machining process indicates that its efficiency is determined by electrodischarge. The use of flexible working electrodes makes it possible to apply simple technological instrumentation and results in the simplicity of the process automation. The aim of the study was to obtain quantitative relationships between the parameters of brush electro discharge mechanical machining (BEDMM) and its effects. The presented experimental research results define the effect of the process input parameters on the performance and roughness of machined surfaces obtained for manganese cast steel.

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Authors and Affiliations

P.S. Młynarczyk
S. Spadło
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Abstract

The problem of the proper functioning of Park-and-Ride facilities seems to be of key importance for ensuring appropriate transport in cities in which the intensity of road traffic is systematically increasing, together with the increase of environmental pollution (air pollution, noise etc.). The attractiveness of a car park of this kind seems obvious – instead of a burdensome journey in one’s own car, one changes the vehicle to fast municipal public transport or another means of transport (a bike, a scooter), or reaches the destination on foot. This results in benefits – above all in terms of comfort (shortening the time of the journey), health advantages etc. As has been proven by experiments, facilities of this kind are an expensive investment, the location of which (e.g. stand-alone) does not always ensure full utilization. The concept presented in the article assumes the possibility of a gradual extension of the multistorey car park following the increase of the demand. The article attempted to demonstrate that one of the sources of increasing attractiveness is the appropriate location (guaranteeing easy commute to the car park), the possibilities to continue the journey in an attractive way, then increasing the attractiveness through the possibility to use various services (shopping, the gym, the swimming pool, cinema, restaurants) and thirdly: the plan of launching the car park and its utilization in the life cycle should ensure the possibility of flexible reacting to changes of the demand (the experiences of the ongoing pandemic indicate that there is no guarantee of ensuring systematic demand increase). An element which also seems significant is the limitation of costs in the initial stage of investments of this kind with the possibility of gradual extension following the change of user habits.
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Authors and Affiliations

Jerzy Paslawski
1
ORCID: ORCID
Tomasz Rudnicki
2
ORCID: ORCID

  1. Poznan University of Technology, Faculty of Civil and Transport Engineering, 5 Piotrowo St., 60-965 Poznan, Poland
  2. Faculty of Civil Engineering and Geodesy, Military University of Technology in Warsaw,2 Gen. S. Kaliskiego St., 01-476 Warsaw, Poland
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Abstract

In this paper, existing knowledge on the behaviour of soil-steel composite structures (SSCSs) has been reviewed. In particular, the response of buried corrugated steel plates (CSPs) to static, semistatic, and dynamic loads has been covered. Furthermore, the performance of SSCS under extreme loading, i.e., loading until failure, has been studied. To investigate the behaviour of the type of composite structures considered, numerous full-scale tests and numerical simulations have been conducted for both arched and box shapes of the shell. In addition, researchers have examined different span lengths and cover depths. Furthermore, to enhance the load-bearing capacity of the composite structures, various stiffening elements have been applied and tested. The reviewshows that the mechanical features of SSCSs are mainly based on the interaction of the shell with the soil backfill. The structures, as a composite system, become appropriately stiff when completely backfilled. For this reason, the construction phase corresponds to the highest values of shell displacement and stress. Moreover, the method of laying and compacting the backfill, as well as the thickness of the cover, has a significant impact on the behaviour of the structure at the stage of operation in both the quantitative and qualitative sense. Finally, a limited number of studies are conducted on the ultimate bearing capacity of large-span SSCS and various reinforcing methods. Considerably more works will need to be done on this topic. It applies to both full scale tests and numerical analysis.
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Authors and Affiliations

Alemu Mosisa Legese
1
ORCID: ORCID
Maciej Sobótka
1
ORCID: ORCID
Czesław Machelski
1
ORCID: ORCID
Adrian Różański
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Faculty of Civil Engineering, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland
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Abstract

Reliable data analysis is one of the hardest tasks in sciences and social sciences. Often misleading and sometimes puzzling results arise when the analysis is done without regard for the special features of the data. In this exposition, I will focus on designing new statistical tools to deal with some prominent questions in Finance and Economics. In particular, I will talk about the following. (1) How to characterize the randomness of variables, motivated by a problem in the pricing of financial options. (2) Uncovering the relation between interest rates on different maturities, now and in the future; the "term structure of interest rates". (3) Modelling the unconventional nonlinear long-memory dynamics that arise from a general-equilibrium economic model, and their implications for exchange rates, stock market indexes, and all macroeconomic variables; with recommendations for trading in financial markets, but also for the design of macroeconomic stabilization policies by governments.

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Authors and Affiliations

Karim M. Abadir
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Abstract

For successful active control with a vibrating plate it is essential to appropriately place actuators. One of the most important criteria is to make the system controllable, so any control objectives can be achieved. In this paper the controllability-oriented placement of actuators is undertaken. First, a theoretical model of a fully clamped rectangular plate is obtained. Optimization criterion based on maximization of controllability of the system is developed. The memetic algorithm is used to find the optimal solution. Obtained results are compared with those obtained by the evolutionary algorithm. The configuration is also validated experimentally.
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Authors and Affiliations

Stanisław Wrona
Marek Pawełczyk

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