Fast and numerically stable Mie solution of EM near field and absorption for stratified spheres

Purpose The purpose of this paper is the development of an analytic computational model for electromagnetic (EM) wave scattering from spherical objects. The main application field is the modeling of electrically large objects, where the standard numerical techniques require huge computational resources. An example is full-wave modeling of the human head in the millimeter-wave regime. Hence, an approximate model or analytical approach is used. Design/methodology/approach The Mie–Debye theorem is used for calculating the EM scattering from a layered dielectric sphere. The evaluation of the analytical expressions involved in the infinite sum has several numerical instabilities, which makes the precise calculation a challenge. The model is validated through an application example with comparing results to numerical calculations (finite element method). The human head model is used with the approximation of a two-layer sphere, where the brain tissues and the cranial bones are represented by homogeneous materials. Findings A significant improvement is introduced for the stable calculation of the Mie coefficients of a core–shell stratified sphere illuminated by a linearly polarized EM plane wave. Using this technique, a semi-analytical expression is derived for the power loss in the sphere resulting in quick and accurate calculations. Originality/value Two methods are introduced in this work with the main objective of estimating the final precision of the results. This is an important aspect for potentially unstable calculations, and the existing implementations have not included this feature so far.

Use of Strategic Management Accounting in the determination of costs in SMEs in the furniture sector

Determining cost in industry of all sizes represents a starting point for determining your desired returns. For this reason, the precise calculation matters greatly to the administration of any economic entity. We are currently facing the so-called knowledge era and where changes are looming permanent, so the colloquially called traditional accounting systems must be reinforced with innovative techniques. The objective of this research work is to propose to Small and Medium-sized companies (PYMES) dedicated to the manufacture of furniture an innovative tool with which the cost is determined starting from a hybrid counting system, a traditional system strengthened with a technique of Strategic management. The Cost Management System proposed by this research is based on the conclusion found in the theoretical framework that a system is not something isolated, but is formed as a gear of techniques, procedures and techniques; according to the needs of the companies under study. To carry out the present research work, a diagnostic analysis of the furniture SMEs was carried out, where information was obtained regarding the characteristics for the determination, measurement, analysis and cost management of these companies. According to the result of said analysis, the system proposal is presented, which is in the validation process for its dissemination and, where appropriate, commercialization, prior to its registration. If the SMEs dedicated to the manufacture of furniture have a system according to their characteristics, it will be possible to determine with certainty indicators that are essential for making strategic decisions that infer in the improvement of the administration of the SMEs under study.

The Fractal Geometry of TiAlNiAu Thin Film Metal System and Its Sheet Resistance (Lateral Size Effect)

This paper investigates the relation between the geometry of metric space of a TiAlNiAu thin film metal system and the geometry of normed functional space of its sheet resistances (functionals), which are elements of the functional space. The investigation provides a means to describe a lateral size effect that involves a dependency in local approximation of sheet resistance Rsq of TiAlNiAu metal film on its lateral linear dimensions (in (x,y) plane). This dependency is defined by fractal geometry of dendrites, or, more specifically, it is a power-law dependency on fractal dimension Df value. The revealed relation has not only fundamental but also a great practical importance both for a precise calculation of thin film metal system Rsq values in designing discreet devices and ICs, and for controlling results at micro- and nanoscale in producing workflow for thin metal films and systems based on them.

Black hole thermodynamics

The chapter presents the Penrose process, Hawking radiation, entropy and the laws of black hole thermodynamics. The Penrose process is derived and the area theorem is stated. A heuristic argument for the Hawking effect is given, emphasising a correct grasp of the concepts and the nature of the result. The Hawking effect and the Unruh effect are further discussed and linked together in a precise calculation. Evaporation of black holes is described. The information paradox is presented.

COMPUTATIONAL IDENTIFICATION OF PROMOTER REGIONS IN PROKARYOTES AND EUKARYOTES

Promoters are modular DNA structures that contain complex regulatory elements required for the initiation of gene transcription. Therefore, the use of machine learning methods to identify promoters is very important for improving genome annotation and understanding transcriptional regulation. In recent years, many methods for predicting eukaryotic and prokaryotic promoters have been proposed. However, the performance of these methods is still far from satisfactory. In this article, we have developed a hybrid method (called IPMD) that combines a position correlation score function and diversity increment with modified Mahalanobis Discriminant to predict eukaryotic and prokaryotic promoters. The precise calculation and identification of promoters remains a challenge because these key DNA regulatory regions have variable structures composed of functional motifs that can provide gene-specific transcription initiation. The promoter is a regulatory DNA region, which is very important for gene transcription regulation. It is located near the transcription start site (TSS) upstream of the corresponding gene. In the post-genomics era, the availability of data makes it possible to build computational models to detect promoters robustly, because these models are expected to be helpful to academia and drug discovery. Until recently, the developed model only focused on distinguishing sequences into promoters and non-promoters. However, by considering the classification of weak and strong promoters, promoter predictors can be further improved. INDEX TERMS—: deep learning, DNA sequence analysis, Promoter prediction, Promoters, Promoter elements

The Role of Frost Processes in the Retreat of River Banks

The rate of bank retreat was measured using erosion pins on the alluvial banks of the rivers in the Podhale region (the boundary zone between Central and Outer Carpathians) during the hydrological year 2013/2014. During the winter half-year (November–April), the bank retreat was mainly caused by processes related to the freezing and thawing of the ground (swelling, creep, downfall). During the summer half-year (May–October), fluvial processes and mass movements such as lateral erosion, washing out, and sliding predominated. The share of fluvial processes in the total annual amount of bank retreat (71 cm on average) was 4 times greater than that of the frost phenomena. Erosion on bank surfaces by frost phenomena during the cold half-year was greatest (up to 38 cm) on the upper parts of banks composed of fine-grained alluvium, while fluvial erosion during the summer half-year (exceeding 80 cm) mostly affected the lower parts of the banks, composed of gravel. The precise calculation of the relative role of frost phenomena in the annual balance of bank erosion was precluded at some stations by the loss of erosion pins in the summer flood.

An Improved Energy-Efficient Hybrid Framework Eehf – Algorithm for Green Cloud Computing

This paper deals with the relocation of multi-target Virtual Machines (VMs) in a cloud server farm. The proposed VM movement technique at the cloud server farm meanders VMs from underutilized to full capacity Physical Machines (PMs) to energy-efficient Physical Machines (PMs). Furthermore, the multi-target VMs relocation technique not only reduces the forced use of PMs and switches but also confirms the essence of administration by preserving the SLA at the cloud server farm. A novel energy-efficient hybrid (EEHF) system for enhancing the proficiency of electrical energy usage in data centers is carried out and evaluated in this paper. Instead of focusing on only one approach as in previous related works, the proposed system is truly based on solicitation preparation and worker booking. Until managing the preparation, the EEH system sorts the errand clients’ requests according to their time and force requirements. It has a booking system that takes power use into account when making planning decisions. It also has a precise calculation that determines if under burdened employees should be rested or dozed in overburdened workers, virtual machines that should be floated, and workers that will receive moved virtual machines VMs. When compared to other strategies, our proposed VMs development strategy may find a great balance among three conflict goals. Furthermore, the shroud-based cloud sim test results show that our proposed multi-target VMs relocation strategy outperforms best-in-class VMs movement strategies like the Random VMs relocation system in terms of energy efficiency and SLA penetration at the cloud server farm.

Performance and determination of Concentration Ratio for a parabolic solar concentrator using a thermographic technique

This work addresses the methodology to determine the exact concentration ratio (CR) for a parabolic solar concentrator (PSC) using thermographic imaging. The value of CR is commonly given in terms of the area of the receiver and not in terms of the area of the image produced by the concentrator on the receiver surface. With thermographic analysis, it is possible to know the real image generated by the PSC on the receiver, which helps to have a precise calculation of CR. It is important to measure the real CR not only for manufacturing purposes but also for the maintenance of solar concentrators, since its miscalculation lowers their energy efficiency or lifespan. In experiments, the real image on the receiver is divided into 4 regions, stratified with an equal temperature difference for each one. With this consideration, CR varied from 20 to 151. To complete the analysis, the energy efficiency is calculated. Since heating is a non-stationary process, thermal efficiency fluctuated during the time of experimentation, having a peak of 25% and a mean value of 15.3%. The irregularities of curvature in the concentrators significantly deteriorate the uniformity of the radiation flux and the energy efficiency due to unused areas of concentration.

A Cascading Mean-Field Approach to the Calculation of Magnetization Fields in Magnetoactive Elastomers

We consider magnetoactive elastomer samples based on the elastic matrix and magnetizable particle inclusions. The application of an external magnetic field to such composite samples causes the magnetization of particles, which start to interact with each other. This interaction is determined by the magnetization field, generated not only by the external magnetic field but also by the magnetic fields arising in the surroundings of interacting particles. Due to the scale invariance of magnetic interactions (O(r−3) in d=3 dimensions), a comprehensive description of the local as well as of the global effects requires a knowledge about the magnetization fields within individual particles and in mesoscopic portions of the composite material. Accordingly, any precise calculation becomes technically infeasible for a specimen comprising billions of particles arranged within macroscopic sample boundaries. Here, we show a way out of this problem by presenting a greatly simplified, but accurate approximation approach for the computation of magnetization fields in the composite samples. Based on the dipole model to magnetic interactions, we introduce the cascading mean-field description of the magnetization field by separating it into three contributions on the micro-, meso-, and macroscale. It is revealed that the contributions are nested into each other, as in the Matryoshka’s toy. Such a description accompanied by an appropriate linearization scheme allows for an efficient and transparent analysis of magnetoactive elastomers under rather general conditions.

A tool for precise calculation of organ doses in voxelised geometries using GAMOS/Geant4 with a graphical user interface

Introduction: The limit of the method of calculating organ doses using voxelised phantoms with a Monte Carlo simulation code is that dose calculation errors in the boundaries of the organs are especially relevant for thin, small or complex geometries. In this report, we describe a tool that helps overcome this problem, accurately calculating organ doses by applying the “parallel geometry” utility feature of Geant4 through the GAMOS framework. Methods and methods: We have tried to simplify the use of this tool by automatically processing the different DICOM image modalities (CT, PT, ST, NM), and by including the automatic conversion of the structures found in a DICOM RTSTRUCT file into Geant4 volumes that build the parallel geometry. For Nuclear Medicine applications, the DICOM PT, ST or NM images are converted into probabilities of generation of primary particles in each voxel, and the DICOM CT images into materials and material densities. For radiotherapy treatments, the DICOM RTPlan or RTIonPlan may also be used, hence the user only needs to describe the accelerator geometry. We also provide a Graphical User Interface for ease of use by for inexperienced users in Monte Carlo. Results: We have tested the functionality of the tool with an I-131 thyroid cancer treatment, and obtained the expected energy deposition and dose differences, given that the particle source, geometry and structures are defined. Conclusions: In summary, we provide an easy-to-use tool to calculate, with high accuracy, organ doses, taking into account their exact geometry as painted by the medical personnel on a voxelised phantom.