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Number of results: 18
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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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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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Abstract

This paper makes a contribution to food research and studies of mobility through analyzing food exchange in a translocal context. Furthermore, by focusing on Muslim women’s practices in the North Caucasus it also contributes to gender studies of post-socialism, which, for the most part, are based on the field material from the non-Muslim part of the Russian population. Anthropologists have viewed social changes through the lens of various food items or consumption patterns. I argue that adding a mobility aspect to the research centered on food can help us discover social changes and practices that may otherwise remain unnoticed. I will show that studying the dynamics of food circulation and human mobility may serve as a good starting point towards the broader study of societies. Thus, by taking people originating from the Shiri village in Daghestan as an example, I look into channels of food sharing to analyze the nature of reproduction of social relations within communities and the cultural entanglements created by the circulation of goods. Furthermore, the analysis of their vernacular practices reveals the existence of informal exchange networks, in particular the ones secured by and for women. Through these networks, food and favors are exchanged, and social bonds and feelings of obligation are created and preserved. Further analysis also reveals social changes connected with mountain abandonment, in particular the growing awareness of the weakening of tukhum (lineage) and village ties. These dynamics reflect recent changes in the Daghestani society that are connected with increased mobility and the processes of (re)islamization.
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Abstract

Middle Palaeolithic land exploitation strategies remain as yet an unexplored element in our understanding of Neanderthal behavioural patterns. Many different approaches to the problem were so far developed. Among others, biological, economic or environmental data concerning Neanderthals were considered as relevant. One of the focus points in such divagations is the issue of raw materials economy as undertaken by Neanderthals. The long-distance transport of knappable minerals (as a basis for the stone tools production) allows an insight into the economy and understanding of the size of land in use by Neanderthals group. Addressing this particular issue from the perspective of the Western Carpathian Mountains allows us to track the trails of mobility or trace possible contact zones between groups, and also to state, that at least in some circumstances Neanderthal groups were infiltrating and possibly crossing this highly elevated area on the S-N axis.
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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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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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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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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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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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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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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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Abstract

According to The European Commission’s regulation numbers 842/2006 and 517/2014, refrigerants whose Global Warming Potential ratio is more than 150, have been prohibited in mobile air conditioning (MAC) since January 2017. Therefore, the commonly used R-134 gas has been banned. The search for a new refrigerant, which grants all the required criteria, has begun. In accordance with new European standards, the gas should have environmentally friendly properties and should not be noxious to human life while operating. In this paper, two alternative substances, which can substitute the banned R134a, have been compared. This is synthetic R1234yf, which belongs to the HFO group, and carbon dioxide, which exists in the natural environment. The chemical build, physical and thermodynamic properties have been described. Scientific articles, which present and compare the technical results of testing both refrigerants, have been discussed. Comparison results, tools used and research methodology have been described in these articles. Alternative gases have been analyzed for their environmental impact and have been checked on the toxic, flammable, impact on ozone depletion and global warming. The threats to human life due to the use of the new refrigerants have been reviewed. The thesis also comprises an economical comparison between the two gases. A short review and conclusions have been presented at the end of the article.
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Abstract

The paper presents the idea of a prosumer energy cloud as a new service dedicated to electricity prosumers. The implementation of the cloud should generate a number of benefits in the following areas: settlements between prosumer and electricity supplier, the development of distributed energy sources in microprocessors and the development of e-mobility. From the prosumer point of view, the proposed idea of a prosumer cloud of energy is dedicated to the virtual storage of energy excess generated in the micro-installation. Physical energy storage in the cloud means recording the volume of electricity introduced into the electricity system from the prosumer’s microprocessors. It is assumed that the energy equivalent to the volume registered in the prosumer cloud can be used at any time at any point in the network infrastructure of the National Power System. Any point of network infrastructure shall be understood as any locally located point of connection of an electricity consumer provided with access authorization. From the point of view of the power grid operators, the idea of a prosumer energy cloud is a conceptual proposition of a service dedicated to the new model of the power system functioning, taking future conditions concerning the significant development of prosumer energy and e-mobility into account. In this concept, electricity would be treated as a commodity only to partial physical storage and above all to trade. In this model a key aspect would be virtual energy storage, that is, the commercial provision by the cloud operator (trading company) of any use of the electricity portfolio by its suppliers. It should be stressed, however, that in the prosumer’s energy cloud functioning, a significant factor would be the cost of guarantees of the use of energy by prosumers at any time and point of connection to the network. This results in the need of taking the presence of certain market risks, both volumetric and cost incurred by clouds operator, which can be minimized by passing a portion of the accumulated volume of generated energy to the cloud operator into account. It should be emphasized that this article presents the first phase of the development of the concept of prosumer energy cloud. However, it is planned to be expanded by the following stages, which include the possibility of controlling and supervising the operation of prosumer installations such as: sources, receivers and physical energy stores, e.g. home energy storage or batteries installed in electric vehicles. Ultimately, it is assumed that the proposed prosumer energy cloud will be outside of the storage of energy (virtual and partly physical) and that aggregation of prosumer resources will create new possibilities for their use to provide a variety of regulatory services, including system ones.
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Abstract

The paper presents results of the field tests on membrane biogas enrichment performed with the application of mobile membrane installation (MMI) with the feed stream up to 10 Nm3/h. The mobile installation equipped with four hollow fibre modules with polyimide type membranes was tested at four different biogas plants. Two of them were using agricultural substrates. The third one was constructed at a municipal wastewater plant and sludge was fermented in a digester and finally in the fourth case biogas was extracted from municipal waste landfill site. Differences in the concentration of bio-methane in feed in all cases were observed and trace compounds were detected as well. High selectivity polyimide membranes, in proper module arrangements, can provide a product of high methane content in all cases. The content of other trace compounds, such as hydrogen sulphide, water vapour and oxygen on the product did not exceed the values stated by standard for a biogas as a vehicle fuel. The traces of hydrogen sulphide and water vapour penetrated faster to the waste stream enriched in carbon dioxide, which could lead to further purification of the product – methane being hold in the retentate (H2O > H2S > CO2 > O2 > CH4 > N2). In the investigated cases, when concentration of N2 was low and concentration of CH4 higher than 50%, it was possible to upgrade methane to concentration above 90% in a two-stage cascade. To performsimulation ofCH4 andCO2 permeation through polyimide membrane,MATLABwas used. Simulation program has included permeation gaseous mixture with methane contents as observed at field tests in the range of 50 and 60% vol. The mass transport process was estimated for a concurrent hollow fibre membrane module for given pressure and temperature conditions and different values of stage cut. The obtained results show good agreement with the experimental data. The highest degree of methane recovery was obtained with gas concentrating in a cascade with recycling of the retentate.
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Abstract

Utilization of drones is going to become predominated in cellular networks as aerial base stations in order to temporary cover areas where stationary base stations cannot serve the users. Detecting optimal location and efficient number of drone-Base Stations (DBSs) are the targets we tackle in this paper. Toward this goal, we first model the problem using mixed integer non-linear programming. The output of the proposed method is the number and the optimal location of DBSs in a two-dimension area, and the object is to maximize the number of covered users. In the second step, since the proposed method is not solvable using conventional methods, we use a proposed method to solve the optimization problem. Simulation results illustrate that the proposed method has achieved its goals.
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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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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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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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