Funneling acoustic waves through largely mismatched channels is of fundamental importance to tailor and transmit sound for a variety of *** electromagnetics,zero-permittivity metamaterials have been used to enhance th...
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Funneling acoustic waves through largely mismatched channels is of fundamental importance to tailor and transmit sound for a variety of *** electromagnetics,zero-permittivity metamaterials have been used to enhance the coupling of energy in and out of ultranarrow channels,based on a phenomenon known as *** metamaterial channels can support total transmission and complete phase uniformity,independent of the channel length,despite being geometrically mismatched with their input and output *** the feld of acoustics,this phenomenon is challenging to achieve,since it requires zero-density metamaterials,typically realized with waveguides periodically loaded with membranes or *** to electromagnetics,the additional challenge is due to the fact that conventional acoustic waveguides do not support a cut-of for the dominant mode of propagation,and therefore zero-index can be achieved only based on a collective resonance of the loading *** we propose and experimentally realize acoustic supercoupling in a dual regime,using a compressibility-nearzero acoustic *** than engineering the channel with subwavelength inclusions,we operate at the cut-of of a higherorder acoustic mode,demonstrating the realization and efcient excitation of a zero-compressibility waveguide with efective sof *** experimentally verify strong transmission through a largely mismatched channel and uniform phase distribution,independent of the channel *** results open interesting pathways towards the realization of extreme acoustic parameters and their implementation in relevant applications,such as ultrasound imaging,acoustic transduction and sensing,nondestructive evaluation,and sound communications.
The purpose of this study is to look for factors, indicators, and build a model of readiness for effective and efficient implementation in order to answer the problems that arise at PT XYZ related to the readiness of ...
The purpose of this study is to look for factors, indicators, and build a model of readiness for effective and efficient implementation in order to answer the problems that arise at PT XYZ related to the readiness of Customer Relationship Management (CRM) implementation. The research method used is the method of collecting data by observing, interviewing, and distributing questionnaires to respondents using the CRM Value Chain theory as a conceptual framework and the research method used in this research is factor analysis to process data obtained from questionnaires. In this study managed to get new factors along with the constituent indicators of these factors as well as an ideal readiness model. It can be concluded that factors related to the readiness of implementing Customer Relationship Management among others are Customer Service Information, Customer Relations Value, Lack of Service and Communication.
Understanding the circumstances that lead to pandemics is important for their prevention. Here, we analyze the genomic diversity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) early in the coronavirus...
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Understanding the circumstances that lead to pandemics is important for their prevention. Here, we analyze the genomic diversity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) early in the coronavirus disease 2019 (COVID-19) pandemic. We show that SARS-CoV-2 genomic diversity before February 2020 likely comprised only two distinct viral lineages, denoted A and B. Phylodynamic rooting methods, coupled with epidemic simulations, reveal that these lineages were the result of at least two separate cross-species transmission events into humans. The first zoonotic transmission likely involved lineage B viruses around 18 November 2019 (23 October-8 December), while the separate introduction of lineage A likely occurred within weeks of this event.
It is for the first time that quantum simulation for high-energy physics (HEP) is studied in the U.S. decadal particle-physics community planning, and in fact until recently, this was not considered a mainstream topic...
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It is for the first time that quantum simulation for high-energy physics (HEP) is studied in the U.S. decadal particle-physics community planning, and in fact until recently, this was not considered a mainstream topic in the community. This fact speaks of a remarkable rate of growth of this subfield over the past few years, stimulated by the impressive advancements in quantum information sciences (QIS) and associated technologies over the past decade, and the significant investment in this area by the government and private sectors in the U.S. and other countries. High-energy physicists have quickly identified problems of importance to our understanding of nature at the most fundamental level, from tiniest distances to cosmological extents, that are intractable with classical computers but may benefit from quantum advantage. They have initiated, and continue to carry out, a vigorous program in theory, algorithm, and hardware co-design for simulations of relevance to the HEP mission. This Roadmap is an attempt to bring this exciting and yet challenging area of research to the spotlight, and to elaborate on what the promises, requirements, challenges, and potential solutions are over the next decade and beyond.
We present high angular-resolution measurements of the thermal Sunyaev-Zel’dovich effect (SZE) toward two galaxy clusters, RCS J2319+0038 at z = 0.9 and HSC J0947−0119 at z = 1.1, by the Atacama Large Millimeter/subm...
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Refactoring is a modification in the internal structure of software, in order to improve quality, understandability and maintainability, without changing its observable behavior. Search Based Software Refactoring (SBS...
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Refactoring is a modification in the internal structure of software, in order to improve quality, understandability and maintainability, without changing its observable behavior. Search Based Software Refactoring (SBSR) deals with automatic software refactoring processes using optimization algorithms. In this context, here we investigate the problem of finding a sequence of refactorings that provides code improvement, according to software quality attributes, expressed by a combination of software metrics. There are multiple criteria to define the quality of a solution, therefore this problem is defined as a Many-Objective Combinatorial Optimization Problem. There is a lack of works that focus on Many-Objective Discrete Problems in SBSR. In this direction, this work proposes a Many-Objective Estimation Distributed Algorithm to find a sequence of refactorings on an object-oriented software. The algorithm explores archiving methods and probabilistic models. A set of experiments is performed, with the aim of investigating which is the best algorithm configuration, regarding the probabilistic model and selection procedure.
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