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Based on the Performative Identity Theory, this study contributes to understand how the identities of women who carry out an economic business activity is shaped. Three cases were analyzed using the shadowing ethnographic technique and in-depth interviews, analyzed from the Discourse Analysis. It was possible to establish that the identity of women is built from the different discourses and scenarios with which they interact, marked mainly by their social class. These heterogeneous contexts determine identities that move between actions that approach them and keep them away from the collective imagination of the masculinities of the businessman, but which bring them closer to a socially constructed imaginary of an entrepreneurial woman with multiple roles and demands.

Metals with a wide range of melting points are deposited by electron beam evaporation under oblique deposition geometry on thermally oxidized Si substrates. During deposition the sample holder is cooled down to 77 K. It is observed that all obliquely deposited metals grow as tilted, high aspect ratio columns and hence with a similar morphology. A comparison of such columns with those deposited at room temperature (300 K) reveals that shadowing dominates the growth process for columns deposited at 77 K, while the impact of surface diffusion is significantly increased at elevated substrate temperatures. Furthermore, it is discussed how the incidence angle of the incoming particle flux and the substrate temperature affect the columnar tilt angles and the porosity of the sculptured thin films. Exemplarily for tilted Al columns deposited at 77 K and at 300 K, in-plane pole figure measurements are carried out. A tendency to form a biaxial texture as well as a change in the crystalline structure depending on the substrate temperature is found for those films.

The use of unmanned aerial vehicles (UAV) to provide services such as the Internet, goods delivery, and air taxis has become a reality in recent years. The use of these aircraft requires a secure communication between the control station and the UAV, which demands the characterization of the communication channel. This paper aims to present a measurement setup using an unmanned aircraft to acquire data for the characterization of the radio frequency channel in a propagation environment with particular vegetation (Caatinga) and a lake. This paper presents the following contributions: identification of the communication channel model that best describes the characteristics of communication; characterization of the effects of large-scale fading, such as path loss and log-normal shadowing; characterization of small-scale fading (multipath and Doppler); and estimation of the aircraft speed from the identified Doppler frequency.

We prove that any generalized hyperbolic operator on any Banach space is structurally stable. As a consequence, we obtain a generalization of the classical Grobman-Hartman theorem. [ABSTRACT FROM AUTHOR]

The National Institute of Information and Communications Technology in Japan has developed vehicle earth stations equipped with an antenna system for the automatic tracking of the Wideband InterNetworking engineering test and Demonstration Satellite "KIZUNA" (WINDS), making it possible to form a satellite link while moving. However, shadowing can have a large impact on satellite communications using directional Ka-band antennas with high rectilinearity. It is estimated that the degree of shadowing due to trees varies with seasons, which is a function of seasonal leaf cover. Therefore, we measured the potential seasonal difference by comparing the attenuation of the received signal from the satellite during a year-long experiment with shadowing from several kinds of trees. No attenuation fluctuations were observed from evergreen trees, whereas seasonal attenuation fluctuations were confirmed from deciduous trees. [ABSTRACT FROM AUTHOR]

We consider the notions of equicontinuity point, sensitivity point and so on from a topological point of view. Many of these notions can be sensibly defined either in terms of (finite) open covers or uniformities. We show that for the notions of equicontinuity point and sensitivity point, Hausdorff or uniform versions coincide in compact Hausdorff spaces and are equivalent to the standard definitions stated in terms of a metric in compact metric spaces. We prove that a uniformly chain transitive map with uniform shadowing property on a compact Hausdorff uniform space is either uniformly equicontinuous or it has no uniform equicontinuity points. [ABSTRACT FROM AUTHOR]

In the recent years photovoltaic (PV) industry has experienced a major growth, caused by the ever present annual decrease in module production prices and the expanding awareness of the general public in terms of renewable energy. There are numerous ways to implement PV modules as an additional energy source for a building, be it mounted on the rooftop, or building integrated (BIPV). An analysis of BIPV consisting of 8 modules with the power of 250 Wp each was carried out for the building of the Chemistry Faculty of Gdansk University of Technology (GUT). It included monthly irradiance and energy generation values and compared them to data obtained by the means of PV-GIS system, after inserting site specific coordinates. Additional research on the same type of a single module with the power of 270 Wp was conducted to provide more insight in this matter. A comprehensible analysis allows for defining a final conclusion for the decrease in energy yield for GUT BIPV installation. Data outputs are lower than expected based on PV-GIS values, as for the most time the facade mounted PV system experiences partial soft shading from the nearby park. Furthermore, it is not located directly facing south, but rather south-east which does not prompt ideal working conditions. [ABSTRACT FROM AUTHOR]

Summary: The average symbol error probability (ASEP) performance over the faded radio frequency (RF) link when the noise is additive in nature and has generalized Laplacian distribution is evaluated in this paper. The additive white generalized Laplacian noise (AWGLN) distribution can model different impulsive and non‐Gaussian noise environments often encountered in practice and provides a robust alternative to Gaussian distribution. A new expression for evaluating the exact symbol error probability over a multilevel M‐ary PSK‐modulated AWGLN channel is derived. Based on the obtained expression, the ASEP for the single‐hop RF link that models the shadowing and fading conditions over the RF channel by a generalized –K (GK) distribution is derived. Further, the error performance of a decode‐and‐forward relayed and GK‐distributed two‐hop RF link is discussed, and the results are validated through numerical plots. [ABSTRACT FROM AUTHOR]

We propose an iterative method to evaluate the feedback control kernel of a chaotic system directly from the system's attractor. Such kernels are currently computed using standard linear optimal control theory, known as linear quadratic regulator theory. This is however applicable only to linear systems, which are obtained by linearizing the system governing equations around a target state. In the present paper, we employ the preconditioned multiple shooting shadowing (PMSS) algorithm to compute the kernel directly from the nonlinear dynamics, thereby bypassing the linear approximation. Using the adjoint version of the PMSS algorithm, we show that we can compute the kernel at any point of the domain in a single computation. The algorithm replaces the standard adjoint equation (that is ill-conditioned for chaotic systems) with a well-conditioned adjoint, producing reliable sensitivities which are used to evaluate the feedback matrix elements. We apply the idea to the Kuramoto–Sivashinsky equation. We compare the computed kernel with that produced by the standard linear quadratic regulator algorithm and note similarities and differences. Both kernels are stabilizing, have compact support and similar shape. We explain the shape using two-point spatial correlations that capture the streaky structure of the solution of the uncontrolled system. [ABSTRACT FROM AUTHOR]

We start from a critique of conventional cartographic representations and a brief survey of the writings in geography and architecture and urbanism on space, gender and sexualities. We will approach the transit of a group of drag queens in Foz do Iguaçu, Paraná, through streets and collective public bathrooms, which we consider transient places. We will report a fieldwork that accompanied this group for three different nights, using the mobile methodology of shadowing, and later on producing two sets of cartographies: the maps of violence, which collaboratively represented the spatial repressions in the mobile experience of these drag queens; and the 'bathly' collages, that is, self-representations of the experiences of some of them in the restrooms. [ABSTRACT FROM AUTHOR]

Let (M,ɗ ) be a metric G-space , ɸ ∶M→M be a continuous map. The notion of the G -average shadowing property (G ASP ) for a continuous map on G -space are introduced and the relation between the G ASP and average shadowing property(ASP)are investigated. We show that if ɸ has GASP, then ɸ^m has GASP for every m∈N. We proved that if a map ɸ be pseudo-equivariant with dense set of G_ɸ-periodic points and has the G ASP then ɸ is weakly G-mixing. We also showed that if ɸ is a G -expansive pseudo-equivariant homeomorphism has the GASP and ɸ is topologically G-mixing then ɸ has a G -specification. We obtained that the identity map ɸ on M has the G ASP if and only if the orbit space M⁄G of M is totally disconnected. Finally, we showed that if ɸ be a pseudo-equivariant map, and the trajectory map, Ψ∶M →M⁄G , is covering map then ɸ has the GASP if and only if the induced map ɸ ̆ ∶M⁄G → M⁄G , has GASP. [ABSTRACT FROM AUTHOR]

Vehicle to vehicle (V2V) communications using dedicated short-range communications (DSRC) are considered a promising technology for enhancing road safety. However, in V2V communications, passenger cars suffer from obstruction of bigger vehicles such as buses or trucks. Based on our measurement, a big vehicle can cause a signal loss from 10 to 15 dB due to shadowing. This results in a shorter communication range and reduces the safety message dissemination capability. In this paper, we analyze the impact of shadowing caused by multiple big vehicles on the V2V communication of passenger cars. We propose a model that takes into account both geometric and stochastic shadowing of multiple big vehicles. In order to cope with the physical size of vehicles and safety distance between them in the real world, we propose to use a repulsive point process called hardcore repulsive Poisson point process (PPP) to model the locations of vehicles. Generating procedure and some basic properties of this process are introduced. Based on the proposed model, we derive the average length of the shadow region and the shadowing loss caused by multiple big vehicles. We show that when the number of big vehicles increases from 10% to 80% of total vehicles in one lane, the shadow region increases from 50 m to 450 m on the road. Furthermore, the shadowing loss causes the relative number of cars within communication range of a typical car to reduce from 90% to between 15% and 50%, depending on whether the big vehicles are in the same or the adjacent lane of the consider car. We analyse the packet collision probability while taking into consideration the big vehicle shadow region and observe significant packet collisions without dedicated bus lanes. [ABSTRACT FROM AUTHOR]

Organizations can be approached both as entities and as constantly evolving phenomena. The former are associated with the term 'organization,' while the latter are specifically associated with 'organizing.' In the second meaning, organizations, such as constantly evolving flows, can make observation problematic. Three of these problems deserve special attention. Many events take place at the same time, which poses a challenge for observation. Then there is a question of what to observe, especially for the researcher outside the organization. And finally, the coordination between the actors is not always directly observable. This paper shows how observation by means of multiple-researcher shadowing (Czarniawska, 2007) or 'multi-shadowing' makes it possible for the observer to tackle these three difficulties. For the observer, shadowing (McDonald, 2005; Mintzberg, 1970) involves physically following the actors of the organization as part of a weak or even nonparticipating observational approach. 'Multi-shadowing' combines simultaneous instances of shadowing different actors in the same unit of time but not of place. We compare shadowing and multi-shadowing with other approaches of solo and multiple-researcher observation. Then, we show the interest and the limits of using multi-shadowing to observe hunting with hounds, which involves activities that, while traditional, borrow a number of characteristics from modern organizations if considered through the prism of organizing. [ABSTRACT FROM AUTHOR]

In situ observation methods have essentially been mobilized to study actors' doings, but they have also been mobilized (through studies in the stream of situated action) to study cognition in these same organizational actors. The existing methodological designs have helped to enhance our knowledge of certain cognitive underpinnings, but they carry two limits: (1) they are deployed following a stacking logic, that is, by triangulation, which is more about compensating for the weaknesses of the component methods than uniting their strengths, and which has the pitfall of capturing cognition and action separately; and (2) they cannot capture all the situated and structuring facets of the cognitive underpinnings of action. Here we propose to overcome these barriers with the SCI design: S for shadowing, C for conversions, and I for an interview borrowing on the 'interview to the double' technique. This design is built in a synergy-guided effort that hinges on tightly meshing these three techniques together at fieldwork deployment. This articulation makes it possible to capture action and cognition together and to surface both the situated and structuring facets of cognition underpinning action. The SCI design is easy enough to deploy in fieldwork across a whole range of research settings. [ABSTRACT FROM AUTHOR]

Signal-to-Interference-plus-Noise Ratio (SINR) measures the quality of the radio link between a base station and a User Equipment (UE). This quality indicator is important for the operator as it is used to measure and to optimize network coverage and the maximum user bitrate (which can be deduced from the SINR using the Shannon formula). In this paper, we study the SINR distribution for the downlink assuming that the received signals from serving and interfering cells undergo a path-loss and log-normal shadowing fading. We show that SINR can be approximated by a log-normal random variable and we give analytical expressions of characteristics parameters of its distribution. We then derive the average SINR expression. Also, we give a closed-expression of the rate probability density function and the outage probability and we obtain closed expressions of the average rate and lower and upper bounds of the average rate. For validation, we first compare theoretical results to Monte-Carlo network simulations and show that all the theoretical curves approximate well those obtained by simulations. Then using real measurements obtained by a measurement campaign, we validate the SINR distribution assumption. Based on a test of normality, we find that the recorded SINR samples are normally distributed in the logarithmic domain. We also show that the theoretical probability density function curves and the histogram of the measured samples of SINR are close. [ABSTRACT FROM AUTHOR]

This article further theorizes exemplary practitioners' roles in neighborhood governance by building on the framework of the four ideal types of practitioners—frontline worker, everyday fixer, social entrepreneur and boundary spanner. An actor-focused approach was applied which delivered data to reconstruct processes in which a single citizen practitioner engaged in an Amsterdam neighborhood. Data were collected through shadowing and interviewing him for 2 months. It is shown how this exemplary practitioner combined and switched between the role characteristics of the four generic types, just like chameleon, during his interactions with other actors in various situations and contexts. During this dynamic role switching, he took on the tasks of a community developer, previously delivered by civil servants. He also facilitated stakeholder collaboration leading to more inclusive and democratic local governance. However, role switching caused him to loose the trust of some citizens on the long term. These findings gain relevance in the context of the reorganization of the Dutch welfare state. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the two-sided limit shadowing property for continuous flows defined in compact metric spaces. We analyse some of the results known for the case of homeomorphisms in the case of continuous flows and observe that some differences appear in this scenario. We prove that the suspension flow of a homeomorphism satisfying the two-sided limit shadowing property also satisfies it. This gives a lot of examples of flows satisfying this property, however, it enlighten an important difference between the case of flows and homeomorphisms. There are flows satisfying the two-sided limit shadowing property that are not topologically mixing, while homeomorphisms satisfying the two-sided limit shadowing property satisfy even the specification property. It can happen that a suspension flow has the two-sided limit shadowing property but the base homeomorphism does not, though it is proved that it must satisfy a strictly weaker property called two-sided limit shadowing with a gap (as in [B. Carvalho, D. Kwietniak. On homeomorphisms with the two-sided limit shadowing property, J. Math Anal. Appl.420 (2014), 801–813]). We define a similar notion of two-sided limit shadowing with a gap for flows and prove that these notions are actually equivalent in the case of flows. Finally, we prove that singular suspension flows (in the sense of [Komuro: One-parameter flows with the pseudo orbit tracing property. Mh. Math.98 (1984) 219–253]) do not satisfy the two-sided limit shadowing property. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to describe a self-assessment assignment which details how an industry analysis and manager interview can be used to provide a realistic perspective of a student's desired future management position. In this assignment students conduct a comprehensive analysis of the industry and position which they desire to hold in the future. One of the central themes and part of the assignment is conducting a qualitative interview with a sitting manager in the job they wish to pursue in the future. Students are encouraged to conduct interviews with more than one manager and if possible, to engage in a day (or longer) of shadowing the manager. The assignment highlights the importance of understanding the work environment and position sought for graduating students and how a classroom exercise can be used postgraduation. In addition, suggestions on adding interview questions and postassignment assessment are given. While this assignment has been used in the author's MBA Leadership class, it can easily be adapted and modified for use in other graduate or undergraduate curricula within, or outside, of business disciplines. [ABSTRACT FROM AUTHOR]

This study examines the role of the decision stage in the recognition of reduced pronunciation variants, specifically variants produced with nasal flaps (e.g. "counter" produced as "couner"). We investigate whether the previously reported disadvantage for nasally flapped variants is located at an early perceptual processing stage or at a post-perceptual decision stage. Experiment 1 replicates the variant effect with a lexical decision task. Experiment 2 uses the psychological refractory period paradigm, suggesting that the variant effect is located at a stage that requires central processing resources. Experiment 3 employed the shadowing task, indicating a significantly smaller variant effect compared to the lexical decision task. In concert, our results suggest that the disadvantage for nasally flapped variants has at least in part a decisional locus, which challenges representational and perceptual accounts of the effect. A mechanism is discussed that describes how decisional factors could cause the disadvantage for reduced variants. [ABSTRACT FROM AUTHOR]

Background: Our nearly 500-member department implemented the shadowing program "Walk in My Shoes" to improve intradepartmental relationships and build a stronger sense of community. The program provides both clinical and non-clinical employees an opportunity to shadow colleagues in their various roles and learn more about one another's contribution to the overarching mission of caring for children and their families. The goal of this study was to understand the impact of the shadowing program on employee perceptions of various roles.Objective: To bridge the gap of understanding among colleagues in order to strengthen workplace interrelatedness, increase understanding of various roles, and decrease preconceived notions about roles, through shadowing.Materials and Methods: A preliminary survey distributed to our department in August 2018 assessed the level of interest in new wellness initiatives, including the shadowing program. The survey gauged which roles participants were interested in shadowing. The survey results revealed that 67 employees were interested in the shadowing program. We selected 39 participants and matched them to a coworker in their area of interest. The roles for shadowing included administrator, Child Life specialist, information technologist, medical assistant, nurse, radiologist, researcher and technologist. Participants were required to complete pre- and post-shadowing surveys to assess their experience. Individuals who hosted the shadow experience also completed a survey.Results: A total of 39 clinical and non-clinical staff members participated in the program. We summarized the pre- and post-survey data using median and interquartile range (IQR) and compared the results using the Wilcoxon signed-rank test. The distribution of preconceived notions about each role was not significantly different between the pre- and post-surveys (P=0.094). However, participants' value, understanding of the role they shadowed, and understanding of how the roles relate to each other were significantly greater (P<0.001). In addition, participants showed great interest in shadowing the specific role again (82%) and shadowing another role (92%). Furthermore, almost all hosts would repeat the experience (96%).Conclusion: Our study showed that intradepartmental shadowing can improve clinical and non-clinical staff employees' perceptions and understanding of each other's roles in overall patient care, which in turn contributes to the broader initiative of workplace wellness. The enthusiasm and willingness of the hosts were essential for sustainability of the program and demonstrated that this type of program is feasible in a large, busy department. [ABSTRACT FROM AUTHOR]

For the free group F 2 acting in S 1 , we will prove that if the minimal set for the action is not a Cantor set, then the action does not have the shadowing property. We will also construct an example, whose minimal set is a Cantor set, that it has the shadowing property. [ABSTRACT FROM AUTHOR]

Although ultrasonic pulse-echo C-scanning is a mature non-destructive evaluation technique for imaging internal damage in composite structures, a major impediment of obtaining a full characterization of the internal damage state is delamination shadowing effects. Specifically, shadowing refers to regions of interest that are behind other delamination planes or discontinuities with respect to the scanning surface. The delamination planes block ultrasonic wave transmission and the regions of interest are thus hidden (i.e. shadowed) from the scan. A methodology has been developed to expand ultrasonic scan data of impacted composites by utilizing damage morphology information that is well established in the composite impact research community, such as matrix cracks bounding delaminations, to estimate shadowed delamination information and matrix cracking. First, impacted flat composite plates were C-scanned by pulse-echo ultrasonic and the results were segmented by depth of damage to establish interface-by-interface delamination information. These delaminations were then fit by bounding lines representing the fiber/matrix crack directions defined by the orientations of plies adjacent to each interface to estimate the shadowed portion of the delamination results. The area inside this boundary was added to the original ultrasonic delamination area to create an estimation of the full delamination state at each shadowed interface. Additionally, because this extension method is based on the interactions between delaminations and matrix cracking, this extension method provides an approximation of the matrix cracking of adjacent plies. Results were compared with X-ray computed tomography scans to assess the effectiveness of the extension method. [ABSTRACT FROM AUTHOR]

The problem of interference management is considered in the context of a linear interference network that is subject to long term channel fluctuations due to shadow fading. The slow fading model used is one where communication takes place over blocks of time slots and each link in the network is subject independently to block erasure with probability $p$. It is assumed that each receiver in the network is interested in one unique message, which is made available at $M$ transmitters. For the case where $M=1$ , the cell association problem is considered, and for $M>1$ , the problem of setting up the backhaul links for Coordinated Multi-Point (CoMP) transmission is investigated. In both cases, optimal schemes from a Degrees of Freedom (DoF) viewpoint are analyzed for the setting of no erasures, and new schemes are proposed with better average DoF performance at higher probabilities of erasure. Assuming separate coding over different deep fading erasure blocks, the average per user DoF for $M=1$ is characterized for every value of $p$ , and optimal message assignments are identified. For $M>1$ , it is first established that there is no strategy for assigning messages to transmitters in networks that is optimal for all values of $p$. The optimal cooperative zero-forcing scheme for $M=2$ is then identified, and shown to be information-theoretically optimal when the size of the largest subnetwork that contains no erased links is at most five. [ABSTRACT FROM AUTHOR]

We begin by defining a homoclinic class for homeomorphisms. Then we prove that if a topological homoclinic class Λ associated with an area-preserving homeomorphism f on a surface M is topologically hyperbolic (i.e. has the shadowing and expansiveness properties), then Λ = M and f is an Anosov homeomorphism. [ABSTRACT FROM AUTHOR]

The effect of shadowing and multipath fading on sensing coverage has been studied in this paper. Rician fading is one of the most widely occurring type of multipath fading. We model the multipath fading by Rician random distribution under LOS propagation conditions with shadowing for the first time. We study the coverage aspect for wireless sensor network in the presence of shadowing and Rician fading. We find that the increasing standard deviation of shadowing and Rician fading has a profound negative impact on the sensing coverage. We note a decreasing trend in the sensing coverage with an increase in both shadowing and multipath Rician fading. The decrease of sensing coverage in our study is compared with the case of shadowing alone. Also, multiple deployment of nodes is demonstrated in which we observe a reduction in the no. of nodes required for sensing coverage. [ABSTRACT FROM AUTHOR]

Sensor nodes in IoT applications exhibit limited computing power, communication range and energy resource. These are some of the major constraints in the deployment of these systems. This leads to a multivariable optimization problem. Further, the variations in geographic conditions such as ground, terrain, atmosphere and mobility between various nodes introduces severe randomness in received signal strength at particular nodes. To mitigate this random nature of wireless link, probabilistic channel models are explored and analyzed. For more realistic estimation, multiple factors such as fading, shadowing, interference and noise must be considered simultaneously. In this paper, the reliability of wireless link in such environment is analyzed by capturing effect of these parameters through compound probability distributions. Expressions for Link and node outage have been obtained and measured through network simulation for reliability analysis. The comparative study with the other available fading models shows that the proposed model is more suitable in approximating real phenomenon of wireless link design. [ABSTRACT FROM AUTHOR]

Background: New doctors are expected to assess and manage acutely deteriorating patients from their first days in the hospital. However, current evidence suggests that medical graduates are not prepared for this. We aimed to explore junior doctors' first experiences with unwell patients and how they developed preparedness over time. Methods: We conducted seven semi-structured interviews with doctors in their first postgraduate year. The interview transcripts underwent inductive thematic analysis using consensual qualitative research approaches. Themes identified were categorised into early experiences of unpreparedness, first experiences of genuine preparedness, and making sense of how they became prepared. Reflection on how participants progressed between the two was facilitated through a sorting and ranking exercise. Results: Most participants initially felt unprepared when responding to acutely unwell patients. They described feeling overwhelmed, apprehensive and challenged. Two main challenges involved knowing when to escalate, and feeling expected to perform beyond their level of competency. A lack of acute care exposure at medical school was a common thread. All participants felt prepared to respond to unwell patients three to six months after starting work. Hands-on experience, reflection, simulation and multidisciplinary team-working were consistently ranked as the most useful learning experiences. Conclusion: Starting work as a doctor is a challenging time and preparedness to manage an acutely deteriorating patient is a common area of concern. As preparedness in acute care ranks poorly compared to other outcomes, we see this as an important area for improvement. Our findings suggest that undergraduates may lack sufficient opportunities for scaffolded decision making in acute care, and that increasing the intensity of clinical shadowing may improve preparedness and should inform future educational interventions. [ABSTRACT FROM AUTHOR]

We address the estimation of the Ricean $K$ factor when the available complex channel samples are noisy and subject to Nakagami- $m$ shadowing, i.e., the line-of-sight component is modeled as a Nakagami- $m$ random variable. We propose two estimators: one based on the expectation-maximization (EM) procedure, and a second one based on the method of moment (MoM). The MoM estimator can be used to initialize the EM procedure. We show by simulations that the two proposed estimators outperform the existing ones. [ABSTRACT FROM AUTHOR]

The susceptibility of millimeter-wave (mmWave) signals to physical blockage and abrupt signal strength variations presents a challenge to reliable 5G communication. This work proposes and examines the feasibility of utilizing lower-frequency signals as early-warning indicators of mobile mmWave signal blockage or recovery. A physics-based channel simulation tool incorporating Fresnel diffraction and image sources is employed to demonstrate that sub-6 GHz signals “lead” mmWave signals in reaching a specific signal-strength threshold by several to tens of milliseconds at mobile speeds, suggesting early-warning systems are viable. This predictive approach stems from frequency-dependent properties of diffraction and does not assume a specific topology or mobile and obstacle speeds. Realistic simulations that include transitions from line of sight (LoS) to non-line of sight (NLoS) and reflection scenarios are employed to verify the proposed prediction capabilities. Moreover, prediction of the strongest multipath component and its angle of arrival (AoA) using sub-6 GHz observations is investigated. [ABSTRACT FROM AUTHOR]

In wireless communication system, various parameters such as average symbol/bit error probability (ASEP/ABEP), outage probability and average channel capacity, etc. are studied for its performance analysis. In this paper, the performance of L-Hoyt/Gamma (HG) composite fading channel with Maximum Ratio Combining (MRC) employing micro-diversity is analyzed. Closed-form expressions for distribution function, moments, outage probability and channel capacity are derived in terms of hypergeometric functions. Further, the expressions of ASEP/ABEP for all formats of coherent and non-coherent modulation techniques involving Q-functions and Marcum Q-function are derived over the composite fading channel. Monte-Carlo simulations are performed to validate our analytical results. The analytical results produced here can be useful in several wireless applications where multipath and shadowing are characterized by Hoyt/Gamma distribution.

Twenty-five years have passed since a teaching technique, called shadowing, was introduced in Japanese EFL contexts. Recently, this technique has gradually been recognized around the world. Given that many studies have been published about shadowing, the time is ripe to summarize the results of the studies and to propose how shadowing should be used. This article introduces shadowing, first referring to theoretical explanations provided so far, especially in terms of attention, cognitive process, and listening process.The article then summarizes past studies on the effects of shadowing on listening and speaking. Next, it discusses challenges in research and also introduces shadowing variations for further use of shadowing. As a classroom teaching tool, this article suggests that beginner level learners should start from shadowing for listening and proceed to shadowing for speaking. [ABSTRACT FROM AUTHOR]

We show that shadowing is a generic property for continuous maps on dendrites. [ABSTRACT FROM AUTHOR]

For any continuous self-map of a compact metric space, we consider the space of chain components and prove that the s-limit shadowing implies the denseness of chain components with the shadowing property. It gives a partial answer to a question raised by Moothathu (2011, [15]). We also prove that the s-limit shadowing is not generic in the space of homeomorphisms of a closed differentiable manifold. [ABSTRACT FROM AUTHOR]

In this paper, we develop the basic theory of the shadowing property for local homeomorphisms of metric locally compact spaces, with a focus on applications to edge shift spaces connected with C*-algebra theory. For the local homeomorphism (the Deaconu–Renault system) associated with a directed graph, we completely characterize the shadowing property in terms of conditions on sets of paths. Using these results, we single out classes of graphs for which the associated system presents the shadowing property, fully characterize the shadowing property for systems associated with certain graphs, and show that the system associated with the rose of infinite petals presents the shadowing property and that the Renewal shift system does not present the shadowing property. [ABSTRACT FROM AUTHOR]

It is well known that the predictability of weather and climate is strongly state-dependent. Special, easily recognisable, and extremely relevant atmospheric states like blockings are associated with anomalous instability. This reflects the general property that the attractors of chaotic systems can feature considerable heterogeneity in terms of dynamical properties, and specifically, of their instability. The attractor of a chaotic system is densely populated by unstable periodic orbits (UPOs) that can be used to approximate any forward trajectory through the so-called shadowing. Dynamical heterogeneity can lead to the presence of UPOs with different number of unstable dimensions. This phenomenon – unstable dimensions variability – is a serious breakdown of hyperbolicity and has considerable implications in terms of the structural stability of the system and of the possibility to model accurately its behaviour through numerical models. As a step in the direction of better understanding the properties of high-dimensional chaotic systems, here we provide an extensive numerical investigation of the variability of the dynamical properties across the attractor of the much studied Lorenz '96 model. By combining the Lyapunov analysis of the tangent space with the study of the shadowing of the chaotic trajectory performed by a very large set of UPOs, we show that the observed variability in the number of unstable dimensions is associated with the presence of a substantial number of finite-time Lyapunov exponents that fluctuate about zero also when very long averaging times are considered. The transition between regions of the attractor with different degrees of instability is associated with a significant drop of the quality of the shadowing. By performing a coarse graining based on the shadowing UPOs, we are able to characterise the slow fluctuations of the system between regions featuring, on the average, anomalously high and anomalously low instability. In turn, such regions are associated, respectively, with states of anomalously high and low energy, thus providing a clear link between the microscopic and thermodynamical properties of the system. • The attractor of the Lorenz '96 model features strong violations of hyperbolicity. • The attractor is populated by UPOs with different number of unstable dimensions. • The finite-time Lyapunov Exponents fluctuate around zero for long averaging times. • Results relevant for predictability and structural stability of general chaotic systems. [ABSTRACT FROM AUTHOR]

In the accelerator applications of slow extraction for High Energy Physics (HEP), one of the prime challenges is the mitigation of beam losses, which is becoming increasingly critical with the continuous rise in beam power. A significant breakthrough was achieved earlier at CERN through the successful deployment of proton beam channeling in a crystal at 400 GeV, effectively diverting the beam away from extraction septa and offering new avenues for improving slow extraction efficiency. However, a crucial question remains whether this approach is still effective at lower and medium proton beam energies. In this paper, we present the promising results of the computer simulation studies of the septum shadowing at 8 GeV for the Mu2e project slow extraction at Fermilab. Across the wide range of beam parameters, the beam loss reduction is shown to range between 40 % and factor of three. [ABSTRACT FROM AUTHOR]

Deep knowledge of how radio waves behave in a practical wireless channel is required for the effective planning and deployment of radio access networks in outdoor-to-indoor (O2I) environments. Using more than 400 non-line-of-sight (NLOS) radio measurements at 3.5 GHz, this study analyzes and validates a novel O2I measurement-based path loss prediction narrowband model that characterizes and estimates shadowing through Kriging techniques. The prediction results of the developed model are compared with those of the most traditional assumption of slow fading as a random variable: COST231, WINNER+, ITU-R, 3GPP urban microcell O2I models and field measured data. The results showed and guaranteed that the predicted path loss accuracy, expressed in terms of the mean error, standard deviation and root mean square error (RMSE) was significantly better with the proposed model; it considerably decreased the average error for both scenarios under evaluation.