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Abstract

Sewage sludge from municipal wastewater treatment plants is currently a serious environmental problem, given its diversity due to the variability of time and heavy metal content. Current research on the monitoring of heavy metals is based on the determination of Pb, Cd, Hg, Ni, Zn, Cu and Cr. This makes any thallium content data difficult to access. The study estimated the degree of contamination of sewage sludge with thallium. The sludge samples came from a sewage treatment plant located in Poland. The results are presented for the total concentration of thallium and its mobile forms. These samples were analyzed by differential pulse voltammetry. The results showed that the average thallium content was 0.203 μg/g and its mobile form was 0.025 μg/g. The conducted research shows that almost 13% of thallium from sewage sludge can be gradually released into the environment.
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Bibliography

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  2. Alvarez-Ayuso, E., Otones, V., Murciego, A., Garcia-Sanchez, A. & Santa Regina, I. (2013). Zinc, cadmium and thallium distribution in soils and plants of area impacted by sphalerite-bearing mine wastes. Geoderma, 207-208, pp. 25-34. DOI:10.1016/j.geoderma.2013.04.033
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  8. Fytili, D. & Zabaniotou, A. (2008). Utilization of sewage sludge in EU application of old and new methods a review. Renewable and Sustainable Energy Reviews, 12 (1), pp. 116-140. DOI: 10.1016/j.rser.2006.05.014
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  11. Kowalik, R,, Gawdzik, J., Gawdzik. B. & Gawdzik, A. (2020). Analysis of the mobility of heavy metals in sludge for the sewage treatment plant in Daleszyce. Structure and Environment, 12, 85 DOI: 10.30540/sae-2020-010
  12. Larner, B., Seen, A. & Townsend, A. (2006). Comparative study of optimized BCR sequential extraction scheme and acid leaching of elements in the certified reference material NIST 2711. Analytica Chimica Acta, 556, pp. 444-449. DOI:10.1016/j.aca.2005.09.058
  13. Łukaszewski, Z., Jakubowska, M., Zembrzuski, W., Karbowska, B. & Pasieczna,A. (2010). Flow – injection differential pulse anodic stripping voltammetry as a tool for thallium monitoring in the environment. Electroanalysis, 22 (17-18), pp. 1963-1966. DOI:10.1002/elan.201000151
  14. Lukaszewski, Z., Karbowska, B., Zembrzuski, W. & Siepak, M. (2012). Thallium in fractions of sediments formed during the 2004 tsunami in Thailand. Ecotoxicology and Environmwntal Safety, 80, pp. 184-189. DOI:10.1016/j.ecoenv.2012.02.026
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Authors and Affiliations

Bożena Karbowska
1
ORCID: ORCID
Włodzimierz Zembrzuski
1
ORCID: ORCID
Joanna Zembrzuska
1
ORCID: ORCID

  1. Poznan University of Technology, Faculty of Chemical Technology, Poland
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Abstract

This paper investigates the implications of the size of budget deficit in the open economy under perfect mobility of capital. For that purpose we construct a general equilibrium model with consumers maximizing the discounted utility of consumption, and firms maximizing profits. Government sets the size of the deficit relative to GDP and controls the structure of public debt. Using standard methods of optimal control theory we solve the model, i.e. we find explicit formulas for all trajectories and the level of welfare. Finally, we show that the higher the deficit-to-GDP ratio, the lower the welfare of consumers. Similarly, welfare increases with the share of foreign creditors in public debt.

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Authors and Affiliations

Michał Konopczyński
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Abstract

In this paper we develop an open-economy endogenous growth model to examine the influence of fiscal policy on the economy in the long run. We allow for public deficit and 5 types of taxes. One of the novel features is separate treatment of interest rates on public and private debt, both of which are linear functions of appropriate debt-to-GDP ratios. Two extreme situations are analyzed: a model of “decentralized economy”, where economic agents do not take into account any externalities, and a model of “benevolent social planner”. We derive the rules of optimal fiscal policy that induce economic agents to internalize all externalities. Theoretical results are illustrated with an empirical analysis for Poland. The optimal values of several fiscal policy instruments for Poland are calculated.

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Authors and Affiliations

Michał Konopczyński
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Abstract

The research aim was to determine the long-term impact of the mine waste stored at the coal waste dump Hałda Ruda on the content of heavy metals in the bottom sediments of the Bytomka River. It is a watercourse flowing along this coal waste dump and has been under its influence for over fifty years. The research also attempted to determine the seasonality of changes (2 years) and mobility of selected elements.

The article presents total contents of Cr, Mn, Ni, Cu, Zn, As, Cd and Pb in the bottom sediments collected from the Bytomka River. It also focuses on the distribution of these elements in particular geochemical fractions determined with the Tessier's sequential chemical extraction procedure. Total element contents were determined with an EDPXRF (Energy Dispersive X-ray Fluorescence) technique. The extractants of particular Tessier's fractions were determined quantitatively with an ICP-MS (Inductively Coupled Plasma Mass Spectrometry) spectrometer. The research results show that the stored waste significantly influences the contents of heavy metals in the Bytomka River bottom sediments. The lowest concentration of heavy metals was observed at the B1 spot (above the dump), while the highest one was measured at the B3 spot (below the dump).

Sequential chemical extraction of the bottom sediments indicates that the Zn content in the ion-exchange and carbonate fractions diminished within a year. Nevertheless, Zn bound to Fe and Mn oxides acted in the opposite way. Mn, Zn and Pb are the most dangerous elements from the viewpoint of environmental hazards, as their total concentrations were high. Moreover, their high contents were observed in the most mobile (ion-exchange and carbonate) fractions. Extremely toxic Cd was bound to the oxide fraction to the largest extent. Cu was mainly bound to the organic fraction while environmentally hazardous Cr was bound to the residual fraction.

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Authors and Affiliations

Czesława Rosik-Dulewska
Magdalena Jabłońska-Czapla
Sebastian Szopa
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Abstract

Laboratory and field experiments have been conducted to study mobility of chromium and lead in

floodplain sediments. The main goal of the research was to verify a hypothesis whether changes of chromium

and lead concentration could be used to estimate the relative age of floodplain deposits. The basis for undertaking such research was the presence of weaving industry centers in the Obra River valley between the 16th and

the 19th century and using Cr and Pb compounds in paint recipes. The Cr and Pb contents were also analyzed in

three vertical profiles unaffected by the field experiments. The age of organic sediments in each of the profiles

was determined using the radiocarbon analysis. The results of the laboratory experiments have shown that the

highest contents of the elements were noted in the surface layer of the sediments placed in the column. However,

the contents decreased during the last phase of the experiments and both vertical and horizontal migration of

both elements was observed. A more intensive mobility was observed in the field test. Its cause could be the

changes of the groundwater level, floodplain inundation and pH conditions in alluvial deposits. Such processes

may have influenced migration of the compounds originating from the weaving industry production; Cr and Pb

contents detected in the profiles unaffected by the field experiment were too small to be used for relative dating of alluvial deposits. Moreover, the alluvial deposits with increased contents of the studied elements may be

older than the period of the weaving industry development. Cr and Pb mobility was especially intensive in the

profiles situated within the near bed zone of the floodplain due to regular inundation, and the activity of erosion

and accumulation processes entraining the studied elements back to transport in the river bed.

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Authors and Affiliations

M. Słowik
Z. Młynarczyk
T. Sobczyński
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Abstract

In this paper, we propose a new algorithm that improves the performance of the operation of Handover (HO) in LTE-Advanced (LTE-A) networks. As recognized, Mobility Management (MM) is an important pillar in LTE/LTE-A systems to provide high quality of service to users on the move. The handover algorithms define the method and the steps to follow to ensure a reliable transfer of the UEs from one cell to another without interruption or degradation of the services offered by the network. In this paper, the authors proposed a new handover algorithm for LTE/LTE-A networks based on the measurement and calculation of two important parameters, namely the available bandwidth and the Received Power (RSRP) at the level of eNodeBs. The proposed scheme named LTE Available Bandwidth and RSRP Based Handover Algorithm (LABRBHA) was tested in comparison with well-known algorithms in the literature as the LHHA, LHHAARC and the INTEGRATOR scheme using the open source simulator LTE-Sim. Finally, the network performances were investigated via three indicators: the number of lost packets during the handover operation, the latency as well as the maximum system throughput. The results reported that our algorithm shows remarkable improvements over other transfer schemes.

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Authors and Affiliations

Ismail Angri
Abdellah Najid
Mohammed Mahfoudi
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Abstract

The study presents the issue of kinematic discrepancy of hydrostatic drive systems of high mobility vehicles, and its impact on the presence of the unfavourable phenomenon of circulating power. Furthermore, it presents a theoretical discussion concerning the capacity of the compensation of kinematic discrepancy by a hydrostatic drive system on the basis of tests using static characteristics.

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Authors and Affiliations

Stanisław Konopka
Marian Janusz Łopatka
Mirosław Przybysz

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Abstract

Recent research has reported that an increasing number of migrants in Norway are concentrated in the low-skilled sectors of the labour market, irrespective of their educational background, thus facilitating the formation of migrant niches in the long term. Despite the growing body of literature that raises the problem of downward professional mobility and deskilling among migrant populations, little scholarly attention has been paid to migrants’ struggles and vulnerabilities as a result of underemployment. Drawing on 30 in-depth interviews, this article explores the common experience of habitus mismatch and suffering among Poles who have worked below their level of competence or professional experience since migrating to Norway. By an-alysing subjective experiences of downward professional and social mobility and the conflict between valued and stigmatised identities, the article examines the various habitus mismatches that contribute to suffering in downwardly mobile Polish migrants.

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Authors and Affiliations

Anna Przybyszewska
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Abstract

This paper compares the idea of the Human Smart City, that Polish cities plan to implement in terms of sustainable mobility, with the solutions implemented by leading Polish cities in this field. Documents developed by the European Commission — Sustainable Urban Mobility Plans (SUMPs) — are an important element contributing to the development of active mobility. This study investigates to what extent Polish cities — which implement sustainable mobility as an element of the smart city idea — are simultaneously applying measures to increase the accessibility of active mobility forms and the directions, tools and methods that are used. The analysis includes solutions developed in eight Polish cities — beneficiaries of the competition of the Ministry of Development Funds and Regional Policy ‘Human Smart City: Smart cities co-created by residents’. These are compared with solutions implemented by three cities that are leaders in sustainable mobility implementation in Poland.
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Authors and Affiliations

Katarzyna Elżbieta Krasowska
1
ORCID: ORCID
Anna Szewczenko
2
ORCID: ORCID
Barbara Rożałowska
3
ORCID: ORCID

  1. West Pomeranian University of Technology in Szczecin Faculty of Architecture
  2. Silesian Technical University Faculty of Architecture
  3. Silesian Technical University Faculty of Organization and Management
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Abstract

This Guest Editorial introduces a special issue entitled Brexit and Beyond: Transforming Mobility and Immobility. The unfolding story of Brexit provided the backdrop to a series of events, organised in 2018 and 2019, which were the result of a collaboration between migration researchers in Warsaw and the UK, funded by the Noble Foundation’s Programme on Modern Poland. The largest event – held in association with IMISCOE – was an international conference, arising from which we invited authors to contribute papers to this special issue on the implications of Brexit for the mobility and immobility of EU citizens, particularly – but not exclusively – from Central and Eastern Europe, living in the UK. As we outline in this Editorial, collectively, the papers comprising the special issue address three key themes: everyday implications and ‘living with Brexit’; renegotiating the ‘intentional unpredictability’ status and settling down; and planning the future and the return to countries of origin. In addition, we include an interview with Professor Nira Yuval-Davis, based on the substance of her closing plenary at the conference – racialisation and bordering. Her insightful analysis remains salient to the current situation – in June 2020, as the UK enters the final months of the Brexit transition period – in the unexpected midst of a global pandemic and an imminent recession.

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Authors and Affiliations

Majella Kilkey
Aneta Piekut
Louise Ryan
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Abstract

This article concerns the use of an integrated RFID system with a mobile robot for the navigation and mapping of closed spaces. The architecture of a prototype mobile robot equipped with a set of RFID readers that performs the mapping functions is described. Laboratory tests of the robot have been carried out using a test stand equipped with a grid of appropriately programmed RFID transponders. A simulation model of the effectiveness of transponder reading by the robot has been prepared. The conclusions from measurements and tests are discussed, and methods for improving the solution are proposed.
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Authors and Affiliations

Bartosz Pawłowicz
1
ORCID: ORCID
Mariusz Skoczylas
1
ORCID: ORCID
Bartosz Trybus
2
ORCID: ORCID
Mateusz Salach
3
ORCID: ORCID
Marcin Hubacz
2
ORCID: ORCID
Damian Mazur
4
ORCID: ORCID

  1. Departmentof Electronic and Telecommunications Systems, Rzeszów University of Technology, WincentegoPola 2, 35-959 Rzeszow, Poland
  2. Department of Computer and ControlEngineering, Rzeszow University of Technology, Wincentego Pola 2, 35-959 Rzeszow, Poland
  3. Department of Complex Systems, Rzeszow Universityof Technology, Wincentego Pola 2, 35-959 Rzeszow, Poland
  4. Department of Electrical andComputer Engineering Fundamentals, Rzeszow University of Technology, Wincentego Pola 2, 35-959Rzeszow, Poland
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Abstract

One of the current challenges in transport is e-mobility, understood as electromobility, ecomobility and mobility economics. E-mobility is nowadays a key focus area of socio-technical change, in terms of attention from policy makers as well as from industry and the public. The societal challenges ahead, in particular climate change put increasing pressure on the current mobility system, due to its tremendous environmental impact. Furthermore e-mobility is seen as major economic opportunity for the automotive industry. In this context, based on the available literature and documents and practical solutions implemented already in cities and agglomerations, the paper discusses the fundamental challenges that cities are to face in the context of the current megatrends. This process will engage diff erent stakeholders in order to make this concept become a reality.

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Authors and Affiliations

Adam Przybyłowski
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Abstract

The article contains a survey of methods of the mobile development with the FMX Application platform, which allows to build multi-platform solutions for the efficient Human-Computer Interaction. The test projects illustrate some important conclusions regarding the design and testing of mobile applications for iOS and Android operating systems. They demonstrate navigation controls designed in the skeumorphic and flat manner with some comparisons based on interviews with users in several age ranges. Test apps provide also touch gestures, sensor integration and connections to remote internet data sources. Some additional considerations about the localization and internationalization of the mobile applications built with the FMX platform were also presented. The proposed implementation of the software engineering methods for the mobile application development provides new insights, valuable for software developers dealing with the new FMX platform on iOS and Android.

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Authors and Affiliations

Zdzisław Sroczyński
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Abstract

This article contributes to the growing debate on reintegration and the positioning of returnees in their home societies. Increasingly, studies focus on returnees’ agency in reintegration processes, their practices of mobility in return and their use of social capital and financial and social remittances acquired abroad. Much less analysed is how ethnicity influences such processes of return and experiences of reintegration. In this paper we examine how returnees belonging to different ethnic groups – Germans, Romanians and Roma – reintegrate in a Romanian multi-ethnic context with marked ethnic inequality and lasting segregation. Fieldwork was carried out in a town that has undergone massive changes in the past 30 years due to the combined effects of foreign direct investment and international migration. Economically, the town changed from a poor and decaying context, to one that was poor but developing and finally to one experiencing strong development. Using a modes-of-integration perspective and analysing returnees’ reintegration and mobilities, we show how return evolved as an ethnicised process in different contexts of reception.
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Authors and Affiliations

Remus Gabriel Anghel
1
ORCID: ORCID
Ovidiu Oltean
2
ORCID: ORCID
Alina Petronela Silian
3
ORCID: ORCID

  1. Department of Sociology, Faculty of Political Sciences, National University of Political Studies and Public Administration, and Romanian Institute for Research on National Minorities, Romania
  2. Department of Political Sciences, Faculty of Political, Administrative and Communication Sciences, Babeș-Bolyai University, Romania
  3. Doctoral School of Sociology, Faculty of Sociology and Social Work, Babeș-Bolyai University and National University of Political Studies and Public Administration, Romania
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Abstract

In recent years, a significant development of technologies related to the control and communication of mobile robots, including Unmanned Aerial Vehicles, has been noticeable. Developing these technologies requires having the necessary hardware and software to enable prototyping and simulation of control algorithms in laboratory conditions. The article presents the Laboratory of Intelligent Mobile Robots equipped with the latest solutions. The laboratory equipment consists of four quadcopter drones (QDrone) and two wheeled robots (QBot), equipped with rich sensor sets, a ground control station with Matlab-Simulink software, OptiTRACK object tracking system, and the necessary infrastructure for communication and security. The paper presents the results of measurements from sensors of robots monitoring various quantities during work. The measurements concerned, among others, the quantities of robots registered by IMU sensors of the tested robots (i.e., accelerometers, magnetometers, gyroscopes and others).

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Authors and Affiliations

Sebastian Dudzik
Piotr Szeląg
Janusz Baran
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Abstract

The paper presents the results of experimental verification on using a zero-sum differential game and H control in the problems of tracking and stabilizing motion of a wheeled mobile robot (WMR). It is a new approach to the synthesis of input-output systems based on the theory of dissipative systems in the sense of the possibility of their practical application. This paper expands upon the problem of optimal control of a nonlinear, nonholonomic wheeled mobile robot by including the reduced impact of changing operating condtions and possible disturbances of the robot’s complex motion. The proposed approach is based on the H∞ control theory and the control is generated by the neural approximation solution to the Hamilton-Jacobi-Isaacs equation. Our verification experiments confirm that the H∞ condition is met for reduced impact of disturbances in the task of tracking and stabilizing the robot motion in the form of changing operating conditions and other disturbances, which made it possible to achieve high accuracy of motion.
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Authors and Affiliations

Zenon Hendzel
1
ORCID: ORCID
Paweł Penar
1

  1. Department of Applied Mechanics and Robotics, Faculty of Mechanical Engineering and Aeronautics, Rzeszów University of Technology, ul. Powstańców Warszawy 12, 35-959 Rzeszów, Poland
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Abstract

The author presents an algorithm of slewing motion control in telescopic crane mounted on a chassis of a truck (mobile crane). The control algorithm allows the crane to carry load to a selected point, and it also ensures suppression of swing at the endpoint of the motion. The attention was focussed mainly on the control of slewing motion of the crane body in the case of non-planar distribution of forces acting on the load during its motion.
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Authors and Affiliations

Jacek Kłosiński
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Abstract

The navigation of mobile robots is a key element of autonomous systems, which allows robots to move effectively and securely in changing environments with greater autonomy and precision. This study aims to provide researchers with a comprehensive guide for selecting the best path-planning methods for their particular projects. We evaluate some popular algorithms that are regularly used in mobile robot navigation, in order to demonstrate their specifications and determine where they are most effective. For example, one algorithm is used to model the problem as a standard graph, and another algorithm is found to be the most suitable for highly dynamic and highly dimensional environments, due to its robust path-planning capabilities and efficient route construction. We also filter high-performance algorithms in terms of computational complexity, accuracy, and robustness. In conclusion, this study provides valuable information on its individual strengths and weaknesses, helping robotics and engineers make informed decisions when selecting the most appropriate algorithm for their specific applications.
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Authors and Affiliations

Mehmet Kara
1
ORCID: ORCID

  1. AGH University of Science and Technology, Krakow, Poland
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Abstract

Even though the discrimination against women in science have been studied for at least half of the century and any many actions have been taken to promote careers of female researchers, their chances are still far from equal. Many barriers have disappeared, but increasingly precarious model of academic career makes it more difficult for women. The interviews conducted with laureates of prestigious competitions by the Foundation for Polish Science allowed for analysis of what Polish researchers think about the role of gender and parenthood in academic career. The have also served to identify factors that were crucial – according to the interviewed female scientists – for their success in science. As the interviews indicate, the requirements od academic career are the same in case of both: men and women, which could suggest lack of discrimination. On the other hand, the expectation that women will be able to meet the criteria set up by male experiences does not mean equal playing field. To assess real chances for academic success, other non-academic aspects of researchers’ life need to be taken into consideration, especially their limitations for dedicating time to research and for mobility. Young researchers – men as well as women – experience increasing uncertainty in regard to their academic future. Growing competition for employment and research funding, makes it much more difficult for women to fulfil the expectations of a fast-track, mobile career. The interviews formed the basis for identification of support mechanisms in this respect.

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Authors and Affiliations

Marta Łazarowicz-Kowalik
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Abstract

This paper investigates the life cycle profiles of income and consumption and relative income mobility in Poland – a transition economy facing rapid structural economic and social changes. According to my results, and in line with the empirical evidence for advanced economies, the age-profiles of average income and consumption in Poland exhibit a hump. The inequality of income over the life cycle is found to flatten relatively quickly in Poland, which contrasts with the approximately linear shape observed in the US. When individual income process is fitted to match the Polish inequality profile, it exhibits less persistence than in the US. Past earnings turn out to affect current income more strongly for the group of more educated individuals. Moreover, and in contrast to the permanent income hypothesis as well as findings for other economies, no evidence of an increase in consumption inequality for households older than 30 years is found. Finally, the obtained estimates of relative income mobility in Poland are higher than those for developed countries.

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Authors and Affiliations

Aleksandra Kolasa
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Abstract

The feasibility of substituting the types of wood usually employed in the making of guitars and violins was analyzed, but without comparing the properties of involved materials as it is often reported; in this work, the vibrational behavior of twelve guitars and three violins built with alternative types of woods was compared to data of classical instruments available in the literature. In the guitars here measured, the back plate and ribs were not made from traditional woods; while in the violins, only the top plate was made from an alternative type of wood. The results showed that changing the wood of back plate and ribs does not radically affect the typical mobility of a guitar; however, the expected mobility for a violin was not clearly obtained substituting the wood of the top plate. Thus it seems feasible to substitute the wood of back plate and ribs in guitars without causing dramatic changes in their performance; in contrast, a change of the wood type for top plate in violins seems inadvisable unless the design of the top plate is modified to compensate the differences between the woods.
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Authors and Affiliations

Jesús Alejandro Torres
Reydezel Torres-Martínez
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Abstract

The growing number of mobile devices and the increasing popularity of multimedia services result in a new challenge of providing mobility in access networks. The paper describes experimental research on media (audio and video) streaming in a mobile IEEE 802.11 b/g/n environment realizing network-based mobility. It is an approach to mobility that requires little or no modification of the mobile terminal. Assessment of relevant parameters has been conducted in an IPv6 testbed. During the tests, both Quality of Service (QoS) and Quality of Experience (QoE) parameters have been considered. Against the background of standard L3 and L2 handovers, an emerging mobility solution named Proxy Mobile IPv6 (PMIPv6) has been examined. Its advantages (L3 connectivity maintenance) and disadvantages (packet loss during handover) are emphasized based on the obtained results. Moreover, a new solution for handover optimization has been proposed. A handoff influence upon audio/video generation and transfer imperfections has been studied and found to be an interesting direction of future work.

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Authors and Affiliations

M. Hoeft
K. Gierlowski
T. Gierszewski
J. Konorski
K. Nowicki
J. Wozniak
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Abstract

In this article, the authors propose and investigate a new concept of HAPS aerostat design in a modular form, which allows for sequential increasing or decreasing of the total volume, up to the desired size. In its initial form, the aerostat has relatively small dimensions but its central cylindrical part is multi-segmented and can be easily extended. The application of controllable construction couplings enables precise control of the aerostat expansion process and significantly improves its vertical mobility. The paper describes details of telescopic aerostat construction, presents a mathematical model of its vertical motion and investigates numerically two volume control strategies aimed at maximization of operation efficiency and minimization of operation cost. The results obtained reveal the main problems that have to be addressed and the factors that play a key role in design of such telescopic aerostats and control of their vertical mobility.

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Authors and Affiliations

L. Knap
C. Graczykowski
J. Holnicki-Szulc
Z. Wołejsza
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Abstract

In order to meet global challenges, cities must be governed efficiently, be compact, and as a result more sustainable, socially coherent, strong and competitive at economic level. Initiatives taken in favour of urban mobility may help in shaping of the global society, putting the main focus on the quality of life, citizens› needs and the principle of sustainable development. These actions aim at focusing citizens› attention on the need to improve air quality, decrease congestion in city’s main streets, but most of all to invest in your own health and physical condition, which increases the level of citizens’ life conditions, and in turn provides the city with considerable economic benefits. However, is it quite a challenge to ensure a sustainable urban mobility pattern which requires a high level of stakeholders’ participation and establishing a detailed complex planning process. The aim of the paper is to present, based on the available literature and data sources and also survey research results, shaping life quality in the aspect of mobility in the context of current megatrends, taking as a case study the CIVITAS DYN@MO project implementation in the city of Gdynia.

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Authors and Affiliations

Adam Przybyłowski

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