regular structure
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Author(s):  
Rui M. Lourenco ◽  
Luis M. N. Tavora ◽  
Pedro A. A. Assuncao ◽  
Lucas A. Thomaz ◽  
Rui Fonseca-Pinto ◽  
...  

AbstractDuring the last decade, there has been an increasing number of applications dealing with multidimensional visual information, either for 3D object representation or feature extraction purposes. In this context, recent advances in light field technology, have been driving research efforts in disparity estimation methods. Among the existing ones, those based on the structure tensor have emerged as very promising to estimate disparity maps from Epipolar Plane Images. However, this approach is known to have two intrinsic limitations: (i) silhouette enlargement and (ii) irregularity of surface normal maps as computed from the estimated disparity. To address these problems, this work proposes a new method for improving disparity maps obtained from the structure-tensor approach by enhancing the silhouette and reducing the noise of planar surfaces in light fields. An edge-based approach is initially used for silhouette improvement through refinement of the estimated disparity values around object edges. Then, a plane detection algorithm, based on a seed growth strategy, is used to estimate planar regions, which in turn are used to guide correction of erroneous disparity values detected in object boundaries. The proposed algorithm shows an average improvement of 98.3% in terms of median angle error for plane surfaces, when compared to regular structure-tensor-based methods, outperforming state-of-the-art methods. The proposed framework also presents very competitive results, in terms of mean square error between disparity maps and their ground truth, when compared with their counterparts.


Author(s):  
Piotr Śpiewanowski ◽  
Oleksandr Talavera ◽  
Linh Vi

The 21st-century economy is increasingly built around data. Firms and individuals upload and store enormous amount of data. Most of the produced data is stored on private servers, but a considerable part is made publicly available across the 1.83 billion websites available online. These data can be accessed by researchers using web-scraping techniques. Web scraping refers to the process of collecting data from web pages either manually or using automation tools or specialized software. Web scraping is possible and relatively simple thanks to the regular structure of the code used for websites designed to be displayed in web browsers. Websites built with HTML can be scraped using standard text-mining tools, either scripts in popular (statistical) programming languages such as Python, Stata, R, or stand-alone dedicated web-scraping tools. Some of those tools do not even require any prior programming skills. Since about 2010, with the omnipresence of social and economic activities on the Internet, web scraping has become increasingly more popular among academic researchers. In contrast to proprietary data, which might not be feasible due to substantial costs, web scraping can make interesting data sources accessible to everyone. Thanks to web scraping, the data are now available in real time and with significantly more details than what has been traditionally offered by statistical offices or commercial data vendors. In fact, many statistical offices have started using web-scraped data, for example, for calculating price indices. Data collected through web scraping has been used in numerous economic and finance projects and can easily complement traditional data sources.


2021 ◽  
Vol 10 (17) ◽  
pp. e128101724420
Author(s):  
Beatriz Lopes da Costa ◽  
Pedro Abreu da Silva Neto ◽  
Magnólia Carneiro de Oliveira ◽  
Maria Juciene Lima Chaves ◽  
Renata Chastinet Braga ◽  
...  

Encapsulation techniques have been used to overcome problems such as instability and degradation of compounds sensitive to process conditions in food production. Electrospraying is a current method, which enables the production of micro and nanocapsules of compounds, which can be incorporated into food. This review provides readers with an overview of the application of electrospraying to natural lipids intended for food application. The objective of this review was to gather articles published on the production of lipid compounds microcapsules via electrospraying and to verify the efficiency of the application of this technique in lipid compounds of importance in the food field. The present study consists of a systematic review using the Periódicos CAPES and the Science Direct databases as research bases. About 139 studies were found, being selected 9 to compose the present study. Based on the results of the studies, it was found that the electrospraying technique for the microencapsulation of lipid compounds provides for obtaining uniform capsules with a regular structure, which are desirable characteristics. This technique helped in the protection of bioactive and thermosensitive compounds, such as β-carotene and omega-3. The application of the method provided oxidative stability to oils during the storage period of the capsules. It was concluded that electrospraying is an efficient technique for microencapsulation of lipid compounds, with advantages, compared to other methods, of promoting the formation of micro or nanocapsules, with regular shape, quickly and without the need for high temperatures.


2021 ◽  
Vol 11 (40) ◽  
pp. 118-119
Author(s):  
Olga Borisovna Zdanova ◽  
Andrey Kimovich Martusevich ◽  
F. Artese

The term “crystallogenesis” was primarily mentioned in 1730. I. Newton in his research “Optics”described a phenomenon of regular structure formation from salt solutions. The latter proved to be the origin of nowadays biocrystallography. Later crystallography has been also applied in pharmacy (medication synthesis) and forensic medicine (toxicology). Moreover, a number of clinically oriented works on crystallography have been issued. This method is simple and safe for investigated people and animals. The purpose of this new medico-biological science is to discover crystallogenesis mechanisms and further to work out the criteria for estimation of various substrates bioinformation and biocrystallisation management on the basis of up-to-date accomplishments in the homoeopathy.


Author(s):  
Ashraf Abdulmunim Abdulmajeed Althanoon ◽  
Younis S Younis

The important first stage in the life cycle of a program is gathering and analysing requirements for creating or developing a system. The classification of program needs is a crucial step that will be used later in the design and implementation phases. The classification process may be done manually, which takes a lot of time, effort, and money, or it can be done automatically using intelligent approaches, which takes a lot less time, effort, and money. Building a system that supports the needs classification process automatically is a crucial part of software development. The goal of this research is to look into the many automatic classification approaches that are currently available. To assist researchers and software developers in selecting the suitable requirement categorization approach, those requirements were divided into functional and non-functional requirements. since natural language is full of ambiguity and is not well defined, and has no regular structure, it is considered somewhat variable. This paper presents machine requirement classification where system development requirements are categorized into functional and non-functional requirements by using two machine learning approaches. During this research paper, MATLAB 2020a was used, as well as the study's results indicate When applying Multinomial Naive Bayes technology, the model achieves the highest accuracy of 95.55 %,93.09 % sensitivity, and 96.48 % precision, However, when using Logist Regression, the suggested model has a classification accuracy of 91.23 %,91.54 % sensitivity, and 94.32 % precision.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260068
Author(s):  
Eduard Rohan ◽  
Jana Camprová Turjanicová ◽  
Václav Liška

A convenient geometrical description of the microvascular network is necessary for computationally efficient mathematical modelling of liver perfusion, metabolic and other physiological processes. The tissue models currently used are based on the generally accepted schematic structure of the parenchyma at the lobular level, assuming its perfect regular structure and geometrical symmetries. Hepatic lobule, portal lobule, or liver acinus are considered usually as autonomous functional units on which particular physiological problems are studied. We propose a new periodic unit—the liver representative periodic cell (LRPC) and establish its geometrical parametrization. The LRPC is constituted by two portal lobulae, such that it contains the liver acinus as a substructure. As a remarkable advantage over the classical phenomenological modelling approaches, the LRPC enables for multiscale modelling based on the periodic homogenization method. Derived macroscopic equations involve so called effective medium parameters, such as the tissue permeability, which reflect the LRPC geometry. In this way, mutual influences between the macroscopic phenomena, such as inhomogeneous perfusion, and the local processes relevant to the lobular (mesoscopic) level are respected. The LRPC based model is intended for its use within a complete hierarchical model of the whole liver. Using the Double-permeability Darcy model obtained by the homogenization, we illustrate the usefulness of the LRPC based modelling to describe the blood perfusion in the parenchyma.


2021 ◽  
Vol 2131 (5) ◽  
pp. 052077
Author(s):  
A Koroleva ◽  
M Frantsuzov ◽  
I Antanenkova

Abstract The required operation of a heat exchanger with spherical filling depends on determining the heat characteristic of the porous medium. Using most existing dependencies to determine the heat-exchange coefficient in a porous medium gives contradictory results. This paper proposes a calculation method to determine heat characteristics of a porous medium (namely, spherical filling) using numerical modeling. This issue is addressed in a 3D setting using the RANS equation systemk- ε RNG, a turbulence model, energy and state equations for gas flows through the porous medium represented as regular packed beds of three types. Two modes are considered, which differ in the working medium type and heat exchange process direction. Modeling is done to determine the following parameters; Reh=100…4·104, Prwb=0.57… 0.919, ε=0.2595… 0.4764, Twb=300… 1900 K, Tw=300… 1900 K. The analysis results of the influence of the temperature factor, porosity, and heat physical properties of the working medium on the heat exchange are represented. Heat characteristics are given for each case scenario: about 360 reference points are obtained. A modified type of criterial dependencyNusf(Reh) is proposed and approximation coefficients are determined.


2021 ◽  
Author(s):  
Christopher Gale ◽  
Mortaza Derakhshani-Molayousefi ◽  
Nancy E. Levinger

Aerosol-OT reverse micelles represent a chemical construct where surfactant molecules self-assemble to stabilize water nanodroplets ~1-10 nm in diameter. Although commonly assumed to adopt a spherical shape, all-atom molecular dynamics simulations and some experimental studies predict a non-spherical shape. If these aggregates are not spherical, then what shape do they take? Because the tools needed to evaluate the shape of something that lacks regular structure, order, or symmetry are not well developed, we present a set of three intuitive metrics- coordinate-pair eccentricity, convexity, and the curvature distribution- that estimate the shape of an amorphous object and we demonstrate their use on a simulated Aerosol-OT reverse micelle. These metrics are all well-established methods and principles in mathematics, and each provides unique information about the shape. Together, these metrics provide intuitive descriptions of amorphous shapes, facilitate ways to quantify those shapes, and follow their changes over time.


2021 ◽  
Vol 1197 (1) ◽  
pp. 012024
Author(s):  
Prashant Hiwase ◽  
Vipul V Taywade ◽  
Sharda P. Siddh

Abstract Now, every day tall constructing structures constructed around the goal of residential and industrial cause etc. Layout of tall buildings both earthquake as well as wind loads got to be take into considered. An irregular structure, failure of structure starts at a point of its weakness and those weaknesses comesups withs separation of mass, stiffness and geometry of that models. The structures having this kinds of discontinuity are called Irregular structures. (H, J, & darshan, 2017) [2]. For example,Structures with the soft storey were the foremost remarkable fallen structures. Therefore, the impact of vertical alignment within the seismic structure of buildings is very significant. The changes in durability and size provide powerful features of those structures that are completely different from the standard structure. For this present evaluation ‘ETABS’ software package is employed. All Reinforced Concrete structural elements are follows as per ‘IS 456:2000 (Plane and Reinforce Concrete-Code of Practice, Bureau of Indian Standard)’. Seismic load follows with respect to IS 1893:2016 along with self-weight of modelles for analysis of the structure. Here 2 kinds of buildings of (G+15) were created one is regular structure and alternative one Mass irregular. To observe, Effect of lateral in both buildings using Seismic load and to check the results,most of maximum displacement for various models and various parameters.


Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2389
Author(s):  
Zhen Zhao ◽  
Chaoqun Xia ◽  
Jianjun Yang

We report the formation of a sole long nanowire structure and the regular nanowire arrays inside a groove on the surface of Fe-based metallic glass upon irradiation of two temporally delayed femtosecond lasers with the identical linear polarization parallel and perpendicular to the groove, respectively. The regular structure formation can be well observed within the delay time of 20 ps for a given total laser fluence of F = 30 mJ/cm2 and within a total laser fluence range of F = 30–42 mJ/cm2 for a given delay time of 5 ps. The structural features, including the unit width and distribution period, are measured on a one-hundred nanometer scale, much less than the incident laser wavelength of 800 nm. The degree of structure regularity sharply contrasts with traditional observations. To comprehensively understand such phenomena, we propose a new physical model by considering the spin angular momentum of surface plasmon and its enhanced inhomogeneous magnetization for the ferromagnetic metal. Therefore, an intensive TE polarized magnetic surface wave is excited to result in the nanometer-scaled energy fringes and the ablative troughs. The theory is further verified by the observation of nanowire structure disappearance at the larger time delays of two laser pulses.


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