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In this work we study strong spectral properties of Ruelle transfer operators related to a large family of Gibbs measures for contact Anosov flows. The ultimate aim is to establish exponential decay of correlations for Hölder observables with respect to a very general class of Gibbs measures. The approach invented in 1997 by Dolgopyat in “On decay of correlations in Anosov flows” and further developed in Stoyanov (2011) is substantially refined here, allowing to deal with much more general situations than before, although we still restrict ourselves to the uniformly hyperbolic case. A rather general procedure is established which produces the desired estimates whenever the Gibbs measure admits a Pesin set with exponentially small tails, that is a Pesin set whose preimages along the flow have measures decaying exponentially fast. We call such Gibbs measures regular. Recent results in Gouëzel and Stoyanov (2019) prove existence of such Pesin sets for hyperbolic diffeomorphisms and flows for a large variety of Gibbs measures determined by Hölder continuous potentials. The strong spectral estimates for Ruelle operators and well-established techniques lead to exponential decay of correlations for Hölder continuous observables, as well as to some other consequences such as: (a) existence of a non-zero analytic continuation of the Ruelle zeta function with a pole at the entropy in a vertical strip containing the entropy in its interior; (b) a Prime Orbit Theorem with an exponentially small error.

The multibody system transfer matrix method (MSTMM), a novel dynamics approach developed during the past three decades, has several advantages compared to conventional dynamics methods. Some of these advantages include avoiding global dynamics equations with a system inertia matrix, utilizing low‐order matrices independent of system degree of freedom, high computational speed, and simplicity of computer implementation. MSTMM has been widely used in computer modeling, simulations, and performance evaluation of approximately 150 different complex mechanical systems. In this paper, the following aspects regarding MSTMM are reviewed: basic theory, algorithms, simulation and design software, and applications. Future research directions and generalization to more applications in various fields of science, technology, and engineering are discussed.

We develop cohomological interpretations for several types of automorphic forms for Hecke triangle groups of infinite covolume. We then use these interpretations to establish explicit isomorphisms between spaces of automorphic forms, cohomology spaces and spaces of eigenfunctions of transfer operators. These results show a deep relation between spectral entities of Hecke surfaces of infinite volume and the dynamics of their geodesic flows.

Individuals vary considerably in how much they earn during their lifetimes. This study examines the role of the tax‐and‐transfer system in mitigating such inequalities, which could otherwise lead to disparities in living standards. Utilizing a life‐cycle model, we determine that the tax‐and‐transfer system offsets 45% of lifetime earnings inequality attributed to differences in productive abilities and education. Additionally, the system insures against 47% of lifetime earnings risk. Implementing a lifetime tax reform that links annual taxes to prior employment could enhance the system's insurance function, though it may involve tradeoffs in terms of employment and overall welfare.

Identification is considered a very important procedure, within the control area, to estimate the best-possible approximate model among different designs. Its significance comes from the fact that more than 75% of the cost associated with an advanced control project is aimed at obtaining a precise mathematical modeling. Therefore, in this work, an exhaustive analysis was carried out to determine the appropriate input stimulus for an unknown real system that must be controlled, with the aim of accurately estimating its transfer function (TF) using the empirical identification method (gray-box). The analysis was performed quantitatively by means of three tests: (i) the PID controller step response was evaluated theoretically; (ii) the controller performance was assessed in a Cartesian robot by tracking a trajectory defined through a Gaussian acceleration profile; (iii) the efficiency of the determined input stimulus with the best performance on inferring the TF for the system to be controlled was verified by assessing its operation in a real system, through repeatability tests, utilizing the integral errors.

A new atom‐transfer radical polymerization (ATRP) initiator 4‐[1‐(2‐dodecyl‐1,3‐dioxo‐2,3‐dihydro‐1H‐benzo[de]isoquinolin‐6‐yl)‐3‐(4‐nitrophenyl)‐4,5‐dihydro‐1H‐pyrazol‐5‐yl]phenyl 2‐bromo‐2‐methylpropanoate (IN) as an electron acceptor (A) and a monomer 2‐(9H‐carbazole‐9‐yl)‐ethyl methacrylate (MCz) as an electron donor (D) were simultaneously introduced into two different D–A polymer systems by using the end‐functionalizing or blending method. The mass percentage of IN in the end‐functionalized polymer PMCz‐IN and the mixed polymer composite PMCz+IN were both controlled at approximately 1.0 wt %. The optical, electrochemical, and surface morphology properties of the two polymeric films prepared by means of spin‐coating technology were comparatively investigated. Sandwich devices based on PMCz‐IN and PMCz+IN demonstrated nonvolatile write‐once‐read‐many‐times memory (WORM) and volatile static random access memory (SRAM) characteristics, respectively, which were further verified by the Kelvin probe force microscopy (KPFM) measurements. The proposed memory mechanism could be attributed to the formation of a stable charge‐transfer (CT) complex for PMCz‐IN and an unstable CT complex for PMCz+IN. Furthermore, the different distribution of IN in the two polymeric films might be the main reason for the stability of the CT complex. Good memories: Two carbazole–pyrazoline‐containing polymer systems (see figure) were synthesized by utilizing the end‐functionalizing or blending method. Devices fabricated from these polymers, ITO/PMCz‐IN/Al and ITO/PMCz+IN/Al, exhibited write‐once‐read‐many‐times memory and static random access memory characteristics, respectively.

DNA is a molecule and assortment of fruitful information of organisms and a wide range of viruses. Polymerase chain reaction (PCR) is a process used to amplify DNA strands in order to generate millions of them and extract the applicable information. Although conventional methods for PCR are flourishing to a certain extent, they have such major drawbacks as contamination, high material consumption, and low-speed function. By the combination of PCR devices with the microfluidic approach and integrating them with droplet generation technology, the mentioned problems can be eliminated. In this study, a novel two-step rapid-cycle droplet-based PCR (dPCR) device, considering the design of microchannel and heat transfer system, has been presented. First, numerous studies have been conducted to select the proper droplet generator for the integration of the droplet generation with the PCR device. Then, with the careful attention to the requirements of a PCR device, the geometry of different zones of the PCR device has been, meticulously, designed. In the next and last step, the heat transfer system for the designed zones of the PCR device has been planned. Afterward, results are examined carefully which indicate that in a cycle of PCR, they are not any major discrepancies between the designed dPCR and the ideal one—the one that is intended to be created.

We argue financial technology (FinTech) is the key driver for financial inclusion, which in turn underlies sustainable balanced development, as embodied in the UN Sustainable Development Goals (SDGs). The full potential of FinTech to support the SDGs may be realized with a progressive approach to the development of underlying infrastructure to support digital financial transformation. Our research suggests that the best way to think about such a strategy is to focus on four primary pillars. The first pillar requires the building of digital identity, simplified account opening and e-KYC systems, supported by the second pillar of open interoperable electronic payments systems. The third pillar involves using the infrastructure of the first and second pillars to underpin electronic provision of government services and payments. The fourth pillar—design of digital financial markets and systems—supports broader access to finance and investment. Implementing the four pillars is a major journey for any economy, but one which has tremendous potential to transform not only finance but economies and societies, through FinTech, financial inclusion and sustainable balanced development.

Current situation in COVID-19 pandemic as well as the significant digital transformation, where the whole world is being forced to participate, are lead for a wide acceptance to use the mobile payments. The main objective for the current study is to focus on analysing the primary variable “intention to use” through the Apple Wallet mobile payment system “apple wallet app” in United Arab Emirates (UAE), in addition to defining a context and evaluating the various antecedents of its use. The main variables that addressed by the current study are ability to use (skilfulness), perceived usefulness, convenience of the system, perceived risk and the primary variable that mentioned before was intention to use. To conduct the study, we invited 422 respondents to an online survey, and we have used a structural equation modelling analysis. The results indicate that mobile user skilfulness is the variable that most influences the intention to use the proposed payment system, followed by perceived usefulness and convenience of the system, while the perceived risk has a weak negative relationship with intention to use mobile payment via apple wallet app in the light of high Cybersecurity Index in the UAE.

The potential use of sheet-like waveguide-based wireless energy transfer systems for a two-way power and/or high-data rate transmission–reception through thick metal walls is investigated. The proposed system utilises the near-field evanescent wave concept to transmit energy and/or data. Compared with wireless energy transfer devices based on magnetic resonance coupling, the transmission efficiency of the investigated method is not affected by the shielding offered by metal sheets. For the investigation, a 150 × 150 mm2 sheet-like waveguide transmitter and a cylindrical wave-cavity receiver were designed. The receiver achieved a transfer efficiency of −3.76 dB, while transmitting power through galvanised iron sheets. The prime objective of this investigation was to sustain the power and/or data transfer efficiency despite the variation of the obstructing metal wall thicknesses from 1.5 to 22.5 mm. The proposed system was designed to operate at 25 MHz, enabling 50 Mbit/s data transfer using a function generator.