Current Approaches in Science and Technology Research Vol. 15

The Kalman filter is one of the most extensively used approaches for estimating system states with unknown statistics in the areas of modem control, communication applications, and signal processing.

By selecting the appropriate estimate technique, a correct and accurate state estimation of a linear or non-linear system can be enhanced. By using several mathematical techniques to linearize the nonlinear system, state estimation can be improved.Kalman filter methods are a common methodology for nonlinear systems that produce linear, unbiased, and minimum variance estimates of unknown state vectors.We attempted to bridge the gap between the Kalman filter and its variants in terms of algorithm and performance when applied to a non-linear system in this study.When only noisy observation data is provided, the techniques mentioned here have been shown to be more effective. This work can be used as theoretical basis for further studies in a number of different directions such as to achieve high computational speed for high dimensional state estimation.

In this study, we propose applying a newly developed technology for the substitution of metamaterials with electromagnetic time reversal procedures to some nanotechnology issues. Metamaterials are also a new exciting field of physics research and have his own essential or enclosure applications. The basic concept is to take use of two key facts: first, we can better localise electromagnetic signals; second, we can often employ waves of lower frequency than we would if we didn't have this technology. To that purpose, we present several specific research cases in which the vector-matrix formalism might be used to nanotechnology.

The goal of this study is to provide regularised asymptotics of the solution of a singularly perturbed parabolic problem when the limit operator has no range and the free term oscillates fast, and the phase derivative vanishes at finite locations. Transition layers are created when the first derivative of the phase of the free term vanishes. It is shown that the asymptotic solution of the problem contains parabolic, inner, corner and rapidly oscillating boundary-layer functions. Corner boundary-layer functions have two components: the first component is described by the product of parabolic boundary layer and boundary layer functions, which have a rapidly oscillating nature of the change, and the second component is described by the product of the inner and parabolic boundary layer functions.

The scale-invariant forms of conservation equations are employed to describe solutions of modified form of equation of motion for the problems of laminar viscous flow across (within) rigid (liquid) sphere and cylinder. Analytical solutions of modified equation of motion in all three regions for both spherical and cylindrical geometry are presented. New solutions for laminar viscous flow across rigid sphere and cylinder are presented with the latter resolving the Stokes paradox for flow across cylinder.

The improvement of working conditions constitutes the major challenge for any company in order to ensure a better productivity. The conditions of work include several elements: material, physical, moral...etc. These can present risks or loads on the health and well-being of workers, which will probably reflecting its profitability. Our study will analyze the working conditions of casting workplace in a steel company of El Hadjar Complex of A nnaba city (Algeria). This work uses the Labour Economics and Sociology Laboratory of France (LEST) method to evaluate the ergonomic-psycho-sociological quality of work in this workstation with the aim of promoting them in a perspective of socio-economic development of the company.

Rubidium is a very soft, silvery-white appearance alkali metal in the first group of periodic table. Rubidium and its compounds have been widely used in electronics, telecommunications, optical and laser technology, biomedical, space technology, academic research especially quantum mechanics-based computing devices because of its exclusive properties like softness, ductility, malleability, strong chemical and photo-emissive activity, low melting point and easy ionization. With rapidly growing technology and science, attention to rubidium will increase even more in near future. Although it is one of the most abundant elements on the Earth’s crust, there is no mineral that is the main component of rubidium. Large amount but low concentration of rubidium exists in brines. It is also produced as minor quantities from lepidolite and pollucite that are lithium and cesium-rich minerals. However, there is limited research on the extraction of rubidium from mining tailings. Rubidium is found in these minerals in a complex structure together with other alkali metals that have very similar properties. So, it is difficult to extract or concentrate rubidium from these sources. Separating rubidium requires a series of physical and chemical processes and is costly. Research on efficient, environmentally friendly, and cheap methods for the recovery of rubidium are being investigated.

This research is based on the detailed design and study of a plant power generation system for green building roofs based on the combination of bionics and design science. Firstly, the selection of power generation plants is carried out through experiments and research. Then, the connection between the plant power generation unit and the internal circuit of the building is studied to generate a complete building roof plant power generation system. This article would introduce the current examples of plant power systems and study a new plant power system. What’s more, it would introduce the application and future of this green power in architecture.

The proximal surfaces of the maxillary posterior teeth overlap and the temporomandibular joints are usually not completely depicted. On the other hand, using this approach, the apical regions of the roots and the nasopalatine space can be well observed. Guidance for technician for proper radiography different factors affecting the quality and anatomy on x-ray and different film artifact. It is concluded that Proper understanding of Radiography and positioning of patient and setting of proper technical factor and elimination of artefact will produce good quality OPG film making easy for interpretation.

The present study emphasizes on the diagnostic value of Orthopantomography and different appearances of pathologies in panoramic radiographs.

Orthopantomography (OPG) has proved its work in dentistry for many years, which often  offers a valuable alternative beyond  the supplementary evidence provided by routine radiological techniques.  It is concluded that OPG is of great value when you are suspecting multiple dental pathology & either maxillary or mandibualr cystic or neoplastic lesion. In case of trauma it is mandatory for complete evaluation as well as pre & post-operative evaluation.

The authors present the theory is numerical / analytical method of multi-scaled 4D geomechanics – geo-dynamics of energy integration in geo-physical rhythms of Eigen-solution of Navier-Stokes equations for multi-level geological time space of evolution in structural compacted mass transfer at the basis of Newton’s Differential Law \({\int^V}{\int^T}pdS.{\partial^2}{\xi/\partial}t^2\) following the integration formula of A. Einstein \(E(u,t)=\boldsymbol{\rho}VC^2+{\int^V}{\int^T}\boldsymbol{\rho}\)‹uv›dtdx. Create the theory (Restoration) and Maintenance of Water Eco-System with Given Parameters. They establish the geophysical seismic rhythms of geological cycles in deep structural formations of the Volga-Urals and Siberia and Kamchatka at dissipative emission, adsorption and nuclear magnetic resonance. The authors propose the systematic velocity model of convective diffusion drift of \(\boldsymbol{\rho}\)‹uv› in deep phase components of heterogenic structures with complexly structured geology in off-shore and global aeration of Middle Ridges from the Urals to the Rocky Mountains. They have also considered the energy time space of more than 4,5 billion years to find the organic markers of quantum photo-synthesis and multiple circulating energy waves in physical and chemical reactions of compacted formation genesis in fissile and relict shales, including the facies with symmetrical absolutely-saturated porosity of classical fields. They establish the geophysical seismic rhythms of geological cycles in deep structural formations of the Volga-Urals and Siberia and Kamchatka at dissipative emission, adsorption and nuclear magnetic resonance. The authors propose the systematic velocity model of convective diffusion drift of \(\boldsymbol{\rho}\)‹uv› in deep phase components of heterogenic structures with complexly structured geology in off-shore and global aeration of Middle Ridges from the Urals to the Rocky Mountains. They have also considered the energy time space of more than 4.5 billion years to find the organic markers of quantum photo-synthesis and multiple circulating energy waves in physical and chemical reactions of compacted formation genesis in fissile and relict shales, including the facies with symmetrical absolutely-saturated porosity of classical fields’ cognitive geology, artefacts.

The authors present the scientific grounding of a new theoretical concept of geo-exploration work, of geo-physical and geo-mechnical models for the unconventional technically recoverable hydrocarbon reserves of the Cis-Ural region. The paper describes heterogeneous balanced volumetric geo-mechanical model for the structural massif of mountain rock post-sedimentation in view of geo-physical synergy and petro-migration. The paper also provides a set of additional studies for seismic, tectono-physical, geological, geo-physical information in a process of search and exploration of hydrocarbon fields and large-scaled construction of surface and subsurface equipment, well drilling and their completion, as well as geo-dynamic studies, geo-hydrogeological simulation of their development stages. The authors have studied the change in stress-deformed status of mountain massifs and the wells in a process of their subsurface operation. They also hae studied the stress fields for the large-scaled reef formations in Zhiguli dislocation and the Cis-Ural region. The authors have scientifically proved the inertia-capillary law of movement conservation (by Darcy-Stokes) and stress-deformed status of square compaction and structural packs of geo-physical rhythms during filtration, petro-migration diffusion and mass-transfer (Bessel’s ray-path and Gaussian distribution). Basing upon the solution of equations related to number of movements (of Navier-Stokes type) for the deformed porous media and conjugated seismic emission of various mass transfer structures the group of authors in a form of a system, have combined filtration as per Darcy and diffusion of structural-topological dislocation of impulses as per Euler with mobile neo-tectonics in porous-cavernous-fractured dissipative accumulation of spectral-phase sedimentation and accumulation of hydrocarbons.

to The present work is aimed to compare OLS (Ordinary Least Squares) and spatial regression models which are methods of calculating the traditional value of land—using data on the practical transaction price of land—and to enhance the applicability of estimation of official land assessment prices set by the Korean government while deducing policy implications for effective implementation. That is, as a way to overcome the limitations of the traditional regression model, we compare various Generalized Regression Models such as SLM (Spatial Lag Model), SEM (Spatial Error Model) with OLS. Consequently, an in-depth diagnosis is conducted to generate a proper estimation model for land pricing, and, also, the analysis focuses on vertical and horizontal equity using COD (Coefficient of Dispersion), COV (Coefficient of Variation) and PRD (Price-Related Differential). The results indicate that SEM is more appropriate than AIC (Akaike info criterion) and SC (Schwarz criterion) in terms of measuring log-likelihood, demonstrating that the spatial autocorrelation model is superior to the traditional regression model. It shows that the SEM is also the best among the tested models with regard to measuring horizontal equity. The spatial econometric model, therefore, is strongly recommended for estimating the prices of land and houses.

The present study aims to determine DCM+, a new congestion control protocol for data networks. It stands for Dynamic Congestion control for Mobile networks. New metrics have been newly invented and introduced like normalized advancing index (NAI) and complete transmission time (CTT). The simulations are done for a simple single-hop-topology (sender-router-receiver). The outcomes of this protocol are excellent and, in most cases, better than other approaches. The excellent properties of our proposed protocol were possible through tracking the available slow-start threshold. We achieved performance improvement, minimized end-to-end delay and large reduction in transmission time. DCM+ was able to combine many advantages at same time of the protocols NewReno and Westwood+. The results show, that DCM+ is extremely adequate for different types of networks. Feedback as main principle of control theory was used to control the congestion in the network. The parameters Round-Trip-Time (RTT) and Retransmission Timeout (RTO) are used as feedback signals to adjust the next congestion window (cwnd).

This paper presents a study of steady laminar flow of a viscous incompressible electrically conducting fluid over a stretching sheet. Exploiting the fact that some features of free-parameter method and the ''separation of variables'' method are alike, an exact solution to the problem is obtained. This solution is compared with an approximate solution to the problem, obtainable by exploiting the idea of stretching the variables of the flow problem and then using least squares method to minimize the residual of a differential equation concerned. Finally, the results obtained, in terms of a magnetic parameter, are discussed. In the applications of the free parameter method and the ‘separation of variables’ method to two-dimensional boundary layer flows, stream function \(\psi\) is introduced and subsequently a non-linear partial differential equation in \(\psi\) is also derived.