PURKH (E-Journals)
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On Roots of Apolar Polynomials
Get PDFThis article continues the exploration of methods based on that of Gian-Carlo Rota that involve apolar invariants used for solving cubic and quintic polynomial equations. These polynomial invariants were disclosed previously as an alternative to and to clarify the umbral method of Rota. Theorems are proved regarding quintic, cubic, andquadratic polynomials that are pairwise apolar in that they satisfy particular polynomial apolar invariant
Inverse Source Problem with Many Frequencies and Attenuation for One-Dimensional Domain
Get PDFIn this article, we consider the one-dimensional inverse source problem for Helmholtz equation with attenuation (damping) factor in a one layer medium. We establish a stability by using multiple frequencies at the two end points of the domain which contains the compact support of the source functions. The main result is an estimate which consists of two parts: the data discrepancy and the high frequency tail. We show that increasing stability possible using multi-frequency wave at the two endpoints
Chelyshkov Collocation Method for Solving Three-Dimensional linear Fredholm Integral Equations
Get PDFThe main purpose of this work is to use the Chelyshkov-collocation method for the solution of three- dimensional Fredholm integral equations. The method is based on the approximate solution in terms of Chelyshkov polynomials with unknown coefficients. This method transforms the integral equation to a system of linear algebraic equations by means of collocation points. Finally, numerical results are included to show the validity and applicability of the method and comparisons are made with existing results
Experimental Evaluation Platform for Voice Transmission Over Internet of Things (VoIoTs)
Get PDFInternet of Things (IoTs) is an example of the last advances in Information and Communication Technologies. In particular, with the revolutionary development of Wireless Sensor Network (WSN) technologies, researchers largely focused on take benefits of integration embedded low-cost, low-power WSN technology in a various IoTs applications. Real-time voice transmission over IoTs is one interesting application that began to be explored by many researchers. Thus, this paper presents a performance study for transmission of voice over WSN (VoWSN) with and without presence of Internet. A framework using a Raspberry Pi3 (RPi3) and open source FFmpeg technology for processing, compressing and streaming voice to a remote computer is proposed, implemented and evaluated. The performance of the proposed framework is evaluated by studying its behavior utilizing three audio encoding algorithms: AC3, MP3 and OPUS with different sampling rates and a set of evaluation metrics such as :One-way delay, jitter, Bandwidth (B.W), CPU usage and packet losses
Framework to Evaluate Emerging Systems Designed to Health Field
Get PDFIn recent years, several information and communication technology systems have emerged as tools to improve sleep quality. Research reveals that poor sleep quality may produce irritability and deficits in performance, concentration, and learning ability in the short term, and is associated with chronic disease in the long term. ICT proposals range from the old Polysomnography (PSG) to innovative systems, such as wearable devices, smartphone applications, and suites of sensors embedded in the users’ environment. Since these technological developments concern a health issue, they have raised important questions regarding their reliability and the level of rigor of the evaluations to which they are submitted. We found that some of the emerging systems that we studied, do not meet the requirements that health science demands to be accepted as clinical tools. The rationale behind this apparent weakness is explained with arguments from the field of evaluations for health interventions and evaluation of technological developments. We propose a framework to evaluate this kind of systems through appropriate scientific methods that provide valuable information to the research. These methods must be performed while designs mature and the feasibility of rigorous evaluations became appropriate
Cloud Computing and Cloud Automata as A New Paradigm for Computation
Get PDFCloud computing addresses how to make right resources available to right computation to improve scaling, resiliency and efficiency of the computation. We argue that cloud computing indeed, is a new paradigm for computation with a higher order of artificial intelligence (AI), and put forward cloud automata as a new model for computation. A high-level AI requires infusing features that mimic human functioning into AI systems. One of the central features is that humans learn all the time and the learning is incremental. Consequently, for AI, we need to use computational models, which reflect incremental learning without stopping (sentience). These features are inherent in reflexive, inductive and limit Turing machines. To construct cloud automata, we use the mathematical theory of Oracles, which include Oracles of Turing machines as its special case. We develop a hierarchical approach based on Oracles with different ranks that includes Oracle AI as a special case. Discussing a named-set approach, we describe an implementation of a high-performance edge cloud using hierarchical name-oriented networking and Oracle AI-based orchestration. We demonstrate how cloud automata with a control overlay allows microservice network provisioning, monitoring and reconfiguration to address non-deterministic fluctuations affecting their behavior without interrupting the overall evolution of computation
High Energy Lasers and New Applications
Get PDFIn the beginning of 1973 in the USSR the study of possibility of LJE designing was conducted. The reflector, located in the tail of the rocket prototype, concentrated the obtained radiation in air and ensured micro-burst that the reactive thrust was created. The successful results of different models of the reflectors tests, which were at the same time the laser light receivers, had been obtained. One should note that all experiments pointed out above were conducted with the use of electric discharge CO2- lasers with power up to 10 kW, while for the injection into orbit of different highly and technologically effective equipment (global network connections, Internet, photo-monitoring of Earth surface, debris cleaning) the radiated power substantially higher is required. Thus, for example, for SC launching with the weight 1000 kg the laser with power not less than 15 MW is necessary[1,2]
Hall Current Effects on MHD Convective Flow Past a Porous Plate with Thermal Radiation, Chemical Reaction and Heat Generation/Absorption
Get PDFIn this paper an attempt is made to study the chemical reaction and combined buoyancy effects of thermal and mass diffusion on MHD convective flow along an infinite vertical porous plate in the presence of Hall current with variable suction and heat generation. A uniform magnetic field is applied in a direction normal to the porous plate. The equations governing the fluid flow are solved using the perturbation technique and the expressions for the velocity, the temperature and the concentration distributions have been obtained. Dimensionless velocity, temperature and concentration profiles are displayed graphically for different values of the parameters entering into the problem like Prandtl number Pr, Hartmann number M, Grashof number G, modified Grash of number Gc, Hall parameter m, Heat source parameter χ, Schmidt number Sc, and Chemical reaction parameter ξ. The Skin-friction coefficient, rate of heat transfer and mass transfer at the plate have been obtained and also discussed through tables. It has been observed that an increase in the Prandtl number leads to a decrease in the primary and secondary velocities, and also a decrease in the temperature. The primary and secondary velocities decrease with increase in the Chemical reaction parameter or Magnetic field parameter
New Exact Solutions for Modified Burgers Vortex
Get PDFExact solutions of Navier-Stokes equation, presenting a new asymmetric vortex, in framework of modified by Shivamoggi Burgers vortex [8], has been obtained both for steady and for specific unsteady cases. The steady vortex is expressed by the function of parabolic cylinder, unsteady one is expressed by Hermit polynomials
Fractal Analysis of The Lunar Bouguer Gravity Field
Get PDFRecent dedicated lunar gravity measure mission provided high-resolution data for the Moon. The collected data are the starting material for the construction of the latest gravity model. Like all celestial bodies, our natural satellite, is not a perfectly spherical object and its internal structure is not formed of homogeneous layers of equal thickness and gravity field varies from place to place. By measuring variations in lunar gravity can determine the density variations and deduce its internal structure. Gravity anomalies of the Moon are caused by concentrations of huge masses of material known as "mascons". Mascons are a symbol of the periods of creation and destruction in the course of the turbulent geological history of the Moon. This article present the results of the fractal analysis of the lunar Bouguer gravity field. The results obtained in the course of the study confirm the fractal geometry of the lunar Bouguer gravity field. The resulting fractal dimensions (D) varies from 1,4-1,5 to 2,4-2,5 and indicate a high level of gravity values fragmentation. Also, the spatial relationship between Bouguer gravity anomalies, "free-air" gravity anomalies and lunar digital elevation model (DEM) are considered.