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Number of results: 10
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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

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

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

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

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

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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