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Wireless communication channel provides a wide area of applications in the field of communication, distributed sensor network and so on. The prominence of the wireless communication channel is because of its robust nature and the sustainability for the precise ranging and the localization. The precision and accuracy of the wireless communication channel largely depend on the localization. The development of the wireless communication channel with improved benefits needs the accurate channel model.

This paper characterizes the tangential path loss model in the WINNER based wireless communication channel model. The measurements taken in the WINNER channel model are compared with the tangential path loss characterized WINNER Channel model.

The model operates well over the varying antenna orientations, measurement condition and the propagation condition. The proposed tangential path loss model is performing well over the various outdoor scenarios.

The proposed characterization shows change in the small-scale parameters (SSP), such as power, delay, angle of arrival and angle of departure as well as the large-scale parameters (LSP), such as RMS delay spread, shadowing, path loss and Ricean factor associated with the model.

In modern society, considering the multi-channel of public opinion information (public opinion) propagation and its strong influence on social development, it is necessary to study its propagation law and discuss the intervention strategy in online social networks (OSN).

First, a conceptual model of double-layer OSN was constructed according to their structural characteristics. Then, a cross-network propagation model of public opinion in double-layer OSN was proposed and discussed its spreading characteristics through numerical simulations. Finally, the control strategy of public opinion, especially the timing and intensity of intervention were discussed.

The results show that the double-layer OSN promotes the propagation of public opinion, and the propagation of public opinion in double-layer OSN has the characteristics of that in two single-layer OSN. Compared with the intervention intensity, the regulator should give the priority to the timing of intervention and try to intervene in the early stage of public opinion propagation.

This study may help the regulators to respond to the propagation of public opinion in OSN more actively and reasonably.

This research has a deep comprehension of the cross-network propagation rules of public opinion and manages the propagation of public opinion.

The purpose of this paper is to study the evolution of financial contagion between Eurozone banks, observing the credit default swaps (CDSs) market during the period 2009–2017.

The authors use a dynamic spatial Durbin model that enables to explore the direct and indirect effects over the short and long run and the transmission channels of the contagion.

The results show how contagion emerges through physical and financial market links between banks. This finding implies that a bank can fail because people expect other related financial institutions to fail as well (self-fulfilling crisis). The study provides statistically significant evidence of the presence of credit risk spillovers in CDS markets. The findings show that equity market dynamics of “neighbouring” banks are important factors in risk transmission.

The research provides a new contribution to the analysis of EZ banking risk contagion, studying CDS spread determinants both under a temporal and spatial dimension. Considering the cross-dependence of credit spreads, the study allowed to verify the non-linearity between the probability of default of a debtor and the observed credit spreads (credit spread puzzle). The authors provide information on the transmission mechanism of contagion and, on the effects among the largest banks. In fact, through the study of short- and long-term impacts, direct and indirect, the paper classify banks of systemic importance according to their effect on the financial system.

Emerging markets are said to have sustained relatively well in the recent global crisis. There are several factors that help explain this popular view, such as, for example, perceived separation from key international financial centres. Still a lot is to be digested in the crisis aftermath with immediate implications for financial markets and real economy. This chapter offers a unique insight into dynamics within transition economies via an extended blended fiscal–monetary policy rules model with possibility of foreign reserves targeting and foreign currency-denominated debt dynamics. Calibration is based on actual data and is done under various targets and financial risk conditions. Prudent monetary policy and fiscal policy initiatives within current context drive the choice of targets. That may help dampen negative impacts of the crisis and thwart potential currency run. This chapter advances three possible post-crisis scenarios, each with unique solution for reserves, exchange rate, sustainable debt and output levels. Categorizing between net exporters and net importers based on countries' external positions, group-specific results are derived. While both groups are susceptible to exchange-rate risk affected by a multitude of shocks due to their fragile financial system, net importers risk high inflation, but net exporters over-borrowing. This chapter contributes to the literature on global financial crisis, macroeconomic policy, and role of nominal targets and foreign reserves in emerging markets.

The purpose of this paper is to describe common methods for evaluating the performance of wireless devices such as wireless sensors in harsh radio environments.

The paper describes how measurements of real‐world propagation environments can be used to support the evaluation process, then presents representative measurement data from multipath environments where sensor networks are likely to be deployed: a fixed‐infrastructure, process‐control environment (here an oil refinery), and a heavy industrial environment (here an automotive assembly plant).

Results on the characterization of multipath in the propagation channel are summarized and how these results may be used in the performance evaluation of sensor networks is discussed.

The paper describes measurement results from environments where little open‐literature data exists on point‐to‐point propagation, specifically high‐multipath environments. These highly reflective scenarios can present difficulties for deployment of sensor networks.

The current paper contributes to the vigorous debate about policies and regulations that would shield financial markets' participants from future events of the financial turmoil. In doing so, the paper aims to broaden the picture of the financial crisis contagion and set it against the background of contemporary European markets. The main purpose of this paper is to present novel aspects of the financial crisis contagion, hence clarifying the contagion theory that still remains confusing and ambiguous for both the academics and financial markets' practitioners.

The paper builds on a simulation model for the financial crisis contagion that is rooted in the qualitative query and backed by semi‐structured interviews with financial markets' participants who possess extensive knowledge about the functioning of European markets and their interconnectedness. With this in mind, the current paper adopts an international investor's perspective on implications that stem from the linkages between European financial markets, flawed regulations and the absence of cross‐border monitoring of the financial crisis contagion.

The findings constitute practical insights into the issues of the financial crisis contagion, hence providing useful advice on policies and regulations that could manage the cross‐market transmission of the financial turmoil and shield financial markets' participants from the episodes of financial crises in the future. The findings reported in this paper also present novel aspects of the contagion processes across the contemporary and systemically important financial markets in Europe.

The practical implications of the current paper gain in significance as the nascent financial crisis sparked off vigorous debate about the need for implementing regulations that would prevent financial markets' participants from the future episodes of global financial crises. At this point, the findings reported in the current paper might be of interest for policy makers and markets' authorities. In addition, the paper attempts to deliver findings that practitioners associated with the contemporary European financial markets would benefit from by understanding the linkages between these markets and ways the financial contagion spreads. Previously, little knowledge of ways financial crises spread across markets caused substantial losses that were incurred by investors.

The current paper addresses the issues of the financial crisis contagion that belong to the group of the most commonly referenced yet least understood notions in finance. Furthermore, the paper focuses on addressing the recently exposed fragility of financial markets' surveillance and regulations. In doing so, the paper employs a pioneering approach to a simulation of the financial crisis contagion by embarking on a qualitative query rather than empirical data. Henceforth, the limitations of the empirical simulations – experienced in the past studies devoted to investigation of the financial crisis contagion – were ameliorated and the findings presented in the paper became of practical use for the markets' practitioners and policymakers.

Utilization of electromagnetic wave (EMW) sensors in an underwater environment has the potential to increase the data rate compared to acoustic-based sensors because of the ability to use larger signal bandwidth. Nevertheless, EMW signals has the drawback of large signal attenuation in underwater, attributed to the high relative permittivity and conductivity of water compared to the atmosphere, hence employment of wide signal bandwidth is necessary to balance the data rate-attenuation trade-off. The purpose of this paper is to analyze the characteristics of both narrowband and wideband EMW signal propagation underwater and devise a path loss model for both cases.

Path loss measurement was conducted using a point-to-point configuration in a laboratory water tank while transmitting narrowband and wideband signals between a pair of wideband underwater antennas. The wideband underwater antennas use buffer-layer structures as the impedance matching layer to optimize the antenna performance when operating underwater. The path loss for narrowband signal was modeled using a multi-layer propagation equation in lossy medium considering losses at the medium boundaries. For the case of the wideband signal, a modified version of the model introducing power integration over bandwidth is adopted. These models were formulated through numerical simulations and verified by measurements.

The measured narrowband path loss marked an 80 dB attenuation using 800 MHz at 2 m distance. The proposed narrowband model agrees well with the measurements, with approximately 3 dB modeling error. Utilization of the proposed wideband path loss model resulted in a reduction of the gradient of the path loss curve compared to the case of the narrowband signal. The measured wideband path loss at 2 m distance underwater was approximately −65 dB, which has been shown to enable a working signal-to-noise ratio of 15 dB. This proves the potential of realizing high data rate transmission using the wideband signal.

The paper proposed a wideband propagation model for an underwater EMW sensor network, using power integration over bandwidth. The effectiveness of using wideband EMW signals in reducing path loss is highlighted, which is seldom discussed in the literature. This result will be of useful reference for using wideband signals in designing a high data rate transmission system in underwater wireless sensor networks, for example, in link budget, performance estimation and parameter design of suitable transmission scheme.

The paper targets on providing new experimental data for validation of the well-established mathematical models within the framework of the lattice Boltzmann method (LBM), which are applied to problems of casting processes in complex mould cavities.

An experimental campaign aiming at the free-surface flow within a system of narrow channels is designed and executed under well-controlled laboratory conditions. An in-house lattice Boltzmann solver is implemented. Its algorithm is described in detail and its performance is tested thoroughly using both the newly recorded experimental data and well-known analytical benchmark tests.

The benchmark tests prove the ability of the implemented algorithm to provide a reliable solution when the surface tension effects become dominant. The convergence of the implemented method is assessed. The two new experimentally studied problems are resolved well by simulations using a coarse computational grid.

A detailed set of original experimental data for validation of computational schemes for simulations of free-surface gravity-driven flow within a system of narrow channels is presented.

The development of wireless communication techniques has increased the employment of positioning systems, such as GPS. Concerning to this, telecommunication providers predicted that position location (PL) will be an integrated service in the third generation cellular phones. Consequently, in this paper we propose a new method to determine the transmitter/receiver distance, which is based on the transmission of several frames with different frequencies.

The propagation of electromagnetic waves depends on internal factors related to its nature and external factors characterized by the medium in which the wave is propagated. In this work, we propose a method to determine the distance between the transmitter and the receiver by solving a system of non‐linear equations, which depends on the physical model of the medium in which the wave is propagated.

The parameters of the model may vary when the link conditions change. As a result, the positioning system must update the model in real time. Following these constraints, a MATLAB simulation to calculate the distance in a satellite‐earth link has been completed. We have shown that scattering phenomena can be used to estimate the transmitter/receiver distance in a radio frequency link. Moreover, any electromagnetic communication in which scattering appears could be considered in the same way.

We have explained a new method to develop a complete PL service. Some of the advantages of this system are that there are no measures in absolute time and that it is not necessary to synchronize the receiving antennas, unlike many current commercial systems.

The purpose of this paper is to analyze a signal propagation in highly metalized environments, which has not been extensively studied in the literature. Having in mind a large number of such applications, better understanding and possibly finding a way of improving communication in these conditions would be highly beneficial.

The analysis is performed in a simulation environment developed by the authors, based on finite difference time domain (FDTD) method, to identify effects that have decisive influence on electromagnetic (EM) wave propagation in the aforementioned conditions. The analysis of the EM field at the reception is modified so that a multiple-field sampling is performed, and maximal values are further used. In practical realizations, this procedure could be implemented by using multiple antennas and selective combining at the reception.

Results show that the existence of metal objects (in the observed case, these are railway tracks), in combination with the appropriate choice of antenna parameters, can be favorably used to improve signal reception. The contribution is manifested through the reduction of the pathloss.

In the performed analysis, one should be aware of the limitations that the FDTD method brings. Those limitations are related to the size of the computational domain and discretization mesh refinement (possibility of modeling geometry in fine details).

Originality of this paper consists of the introduced modification in the analysis of signal propagation in heavily metalized environment. Namely, a multiple-field sampling in the reception zone (in one plane, dimensions λ × λ = 12.5 cm X 12.5 cm) is performed using several probes in simulation environment. In this way, a qualitative analysis is performed more efficiently, which made it is possible to distinguish and identify different propagation mechanisms.