New modeling approach of laser communication in constellation and through atmospheric disturbances

Laser communication between satellites in the constellation and from the satellites to ground stations offers a gigantic data rate for the users. This principal advantage drives telecom companies to develop this technology to use it like a carrier signal, the most disadvantage of this technology is the need to very complicated pointing systems between the transmitter and the receiver due to a very small beam divergence, continually moving of satellites in orbits and the distance between the satellites (tens of thousands of kilometers). The laser beam suffers continuously from several factors like atmospheric turbulences, internal and external vibrations. All these factors lead to an increase in the bit errors rate and cause degradation in the communication quality. This paper deals with a new method of modelisation of external effects in transmission of signal light from a ground station to the satellite through atmospheric disturbances. Indeed, an in-depth investigation, of the influences of satellite vibrationsinlaser signal transmission between satellites constellation, has been conducted by studying the effect of the intensity of vibrations on the optical signal amplitude. Some solutions are proposed to improve the efficiency of optical satellites communications.

A Numerically Efficient Technique for the Analysis of Metamaterial- and Metasurface-based Antennas

Metasurface-based antennas have received considerable recent attention in recent years because they are not only useful for designing new antennas, but for improving the performance of legacy designs as well. However, systematically designing these antennas is challenging because the antennas are usually multiscale in nature and they typically require a long time when simulated by using commercial solvers. In this work, we present a new approach for analyzing antennas that utilize Metasurfaces (MTSs) and Metamaterial (MTMs). The proposed method departs from the widely used technique based on an anisotropic impedance representation of the surface and relies on an equivalent medium approach instead. The principal advantage of the proposed approach is that such an equivalent medium representation can be conveniently inserted directly in commercial EM solvers, circumventing the need to develop special numerical EM simulation codes to handle metasurfaces. Several illustrative examples are presented in the paper to demonstrate the efficacy of the present approach when simulating MTS- and MTMbased antennas.

TEACHING NOUN-PHRASE COMPOSITION IN EAP/ESP CONTEXT: A CORPUS-ASSISTED APPROACH TO OVERCOME A DIDACTIC GAP

Attributive noun phrases, namely noun + noun constructions (NNCs), is an essential typological characteristic of academic style. However, errors in their production and use are not uncommon even in the writing of advanced Russian users of academic English. As such errors slow down reading and, in some cases, lead to misinterpretations, they may be a hindrance to the publication of research results in international journals. Aiming at facilitating NNC instruction, the study focuses on linguistic and didactic aspects of this construction. It highlights NNC complexity and a lack of consensus among researchers as to their linguistic status and semantic nature. The research demonstrates that NNCs do not find proper interpretation in EAP/ESP teaching literature, which results in their misuse by non-native English contributors to international scientific journals. Based on some published practice and personal experience in teaching academic skills, the research lays down a corpus-assisted approach to teaching students to master the grammar and use of NNCs in their own discipline texts. The principal advantage of this approach is that it provides students with patterns of NNP expert use and aids EAP/ESP instructors to develop discipline-specific didactic materials based on reliable and up-to-date facts on generating NNCs.

A Structural Approach to the Monomyth in Contemporary Action Cinema: Dredd, John Wick, and Mad Max: Fury Road

The aim of the thesis is to provide an overview of three contemporary action films: Dredd 3D, John Wick, and Mad Max: Fury Road, through a so-called "bio-structuralist" approach - combining archetypal criticism, literary Darwinism, and narratology, into a unified, holistic theoretical model.The thesis is divided into four main parts: (1) an introduction, that gives a rationale for the aim, scope, and the design of the thesis, (2) a theoretical framework, which provides both an overview of the theories and fits them in the general model, (3) a part including the case studies, that puts the theoretical approach to the test, and finally (4) a conclusion that gives a verdict on the feasibility of the model and summarizes the findings.A particular emphasis is put on the monomyth as a story paradigm that all the films in the case studies share, whose combination of a biologically dictated scaffolding, and cultural brickwork is an excellent testing ground for the theoretical model.In addition to the attempts of revealing glimpses of our evolved nature in the plots, narrative conventions, cinematography, themes, motivations, settings, and character networks in the films, the thesis attempts to balance the hardliner literary Darwinist stance of the dominance of biology over culture, with an acknowledgment of the existence of cultural transmission and stylistic evolution. Thus, the thesis proposes terminology that differentiates between cultural units totally dominated by biology, partially tied to it, and completely independent of it, albeit spread in ways reminiscent of biological evolution.The proposed theoretical model is shown to be a viable alternative to post-structuralist approaches as far as the study of action cinema is concerned, with its ample scope serving as its principal advantage.

On Spectral Characterization of Nonuniform Hyperbolicity

We give a complete functional theoretic characterization of tempered exponential dichotomies in terms of the invertibility of certain linear operators acting on a suitable Frechét space. In sharp contrast to previous results, we consider noninvertible linear cocycles acting on infinite-dimensional spaces. The principal advantage of our results is that they avoid the use of Lyapunov norms.

Scaled Prioritized Geometric Aggregation Operators and Their Applications to Decision Making

This paper uses the priority labels to express the detailed prioritized relationship between criteria and develops some scaled prioritized geometric aggregation operators, including the scaled prioritized geometric score (SPGS) operator and the scaled prioritized geometric averaging (SPGA) operator. We also present the uncertain scaled prioritized geometric scoring (USPGS) operator and the uncertain scaled prioritized geometric averaging (USPGA) operator. We investigate the properties of these operators and build the models to derive the weights by maximizing square deviations from a possible range to distinguish the candidate alternatives. The principal advantage of these scaled prioritized geometric aggregation operators is that they are very stable and satisfy monotonicity. Furthermore, we investigate approaches to multi-attribute decision making based on the proposed operators or models and examples are illustrated to show the feasibility and validity of the new approaches. Finally, some further discussions are given.

Dynamic Analysis of Delaminated Beams

To investigate the dynamic behavior of beams with partially delaminated layers, a model is presented in this work. This model takes into account the lateral strains. The principal advantage of the element is that it allows the modeling of delamination anywhere in the structure. The region without delamination is modeled to carry constant peel and shear stresses. Numerical results of the present model are presented and its performance is evaluated.

ИСПОЛЬЗОВАНИЕ ДАННЫХ МЕЧЕНИЯ И ПОВТОРНОГО ОТЛОВА ДЛЯ ОПРЕДЕЛЕНИЯ РАЗМЕРА ПОПУЛЯЦИИ

<p>Marked and capture-recapture methods are the main alternative to the methods of absolute count for determination of the populations size within the limits of biotope. Principal advantage of these methods is the absence of dependence between the calculation error of population size and biotope area. The basic lack of the methods is the results’ dependence on a sample size.</p> <p>This article aims to fill the existent gaps in national ecological literature concerning the usage of these methods and to present the algorithms of determination of population size from the data of marked and capture–recapture methods.</p> <p><em>Key words: population, marked methods, capture-recapture methods, mathematical methods.</em></p>

Fishing, Commitment, and Communication: A Proposal for Comprehensive Nonbinding Research Registration

Social scientists generally enjoy substantial latitude in selecting measures and models for hypothesis testing. Coupled with publication and related biases, this latitude raises the concern that researchers may intentionally or unintentionally select models that yield positive findings, leading to an unreliable body of published research. To combat this “fishing” problem in medical studies, leading journals now require preregistration of designs that emphasize the prior identification of dependent and independent variables. However, we demonstrate here that even with this level of advanced specification, the scope for fishing is considerable when there is latitude over selection of covariates, subgroups, and other elements of an analysis plan. These concerns could be addressed through the use of a form of comprehensive registration. We experiment with such an approach in the context of an ongoing field experiment for which we drafted a complete “mock report” of findings using fake data on treatment assignment. We describe the advantages and disadvantages of this form of registration and propose that a comprehensive but nonbinding approach be adopted as a first step to combat fishing by social scientists. Likely effects of comprehensive but nonbinding registration are discussed, the principal advantage being communication rather than commitment, in particular that it generates a clear distinction between exploratory analyses and genuine tests.

Contribution to the Mapping of the Landslide of Ain El Hammam (Algeria)

The town of Ain El Hammam is based in crest of a hill affected by an active and extensive landslide. The complexity and significant evolution of this instability makes risk management more difficult. We realized in this paper a mapping of the slope and a study of risk and hazard-induced by ground movements in this region and this by taking into account the probable causes of instability. The principal advantage of the model of assessment of hazard developed is the possibility to realize punctual studies of the risk on natural or artificial slopes. Moreover, this work constitutes just a contribution to the safety management of Ain El Hammam.