bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arduino data-logger and artificial neural network to data analysis
Authors: Contreras Contreras G F , Dulcé-Moreno H J , Ardila Melo R 
Published: November 2019

Abstract
This work takes thermodynamic modelling through computer science for incubation process at domestic birds, that has presented energy consumption significantly high than energy used in processes. Thus, a data analysis was applied upon variables of temperature and relative humidity for heating zones, trying to know how much energy supplied by source was used, as well as, voltage and current variables are measured in the same moment that temperature and relative humidity are acquired. Then, data analysis was done using artificial neural networks models with samples obtained from sensors, where real process is highly time- variant, fixing environment conditions at the moment required. Therefore, with this system has been obtained an air flow of 3.4375 10−2 m3/J using a anemometer respect to electrical energy supplied by fans, giving 9.4818 W of average power using ceramics resistances, and testing an adaptive controller where its variables are fitted using equations obtained from data analysis. In contrast, colombian farmers have decreased economic conditions to maintain them productions due to free trade agreements implemented lastly, indeed this system was developed using open- source software and hardware to avoid costs in acquisition by licensing politicians or periodic subscription to a specific product developed by companies.
Evaluation and analysis of structures with porch system in lightweight concrete by thermally expanded clay from San José de Cúcuta metropolitan area, Colombia
Authors: Palacios J D , Rojas J P , Cáceres J R 
Published: November 2019

Abstract
The increase in the world population has caused cities to grow vertically, increasing the amount of high-rise buildings, which is why there is a need to develop building materials with greater efficiency, that is, resistant and with less density to the conventional. The objective is to analyze the mechanical behavior of buildings with portico system when being designed with lightweight concrete mixtures made with thermally expanded clay from materials in the San José de Cúcuta metropolitan area, Colombia. Eight structural models were made using the finite element method with the Etabs® software, varying the building height and the concrete type that was used, in order to compare the properties and lightweight concrete characteristics contrasted with the conventional concrete. The modeled buildings were located on land with a capacity of 200 KPa and residential use. The San José de Cúcuta city is located on an area of high seismic threat according to the Colombian construction of resistant earthquake. It was determined that lightweight concrete manufactured with materials from the San José de Cúcuta metropolitan area, Colombia, is structural since it has a compressive strength at 28 days of 26 MPa on average and equilibrium density of 1646.16 Kg/m3 complying with the requirements minimums required by the Colombian regulation of resistant earthquake construction for a concrete to be considered light and structural. It was found that when using lightweight structural concrete in the design of joists and slabs, there is a 10% decrease in dead loads that reach the foundations of the structure, which implies a reduction in the dimensions of the foundations.
Thermal behavior evaluation of clays from algodonal formation and their impact on technological properties
Authors: Guerrero-Gómez G , Escobar-Mora N J , Nolasco-Serna C 
Published: November 2019

Abstract
It is presents the characterization of the clays from the algodonal formation and the mechanical properties of the products manufactured in brickyard “Hora”, located in Ocaña, Norte de Santander, Colombia.Tests of scanning electron microscopy, thermal gravimetric analysis, differential scanning calorimetry, initial rate of absorption, 24-hour immersion, compressive strength, and modulus of rupture were performed. The results indicate that the clay contains a considerable amount of silico-aluminate, while the products have low mechanical strength and high percentage of water absorption. The clays used present difficulty in the process of shaping and compacting the products. None of the samples comply with the values established in the standard and do not allow their use as non-structural masonry products for interior or exterior use.
Characterization of commercial luminescent powders
Authors: Paredes R A , Roa K L , Castro H F , Rodriguez G P 
Published: November 2019

Abstract
Luminescent powders have attracted the attention of scientists, boosting properties as specific as mechanoluminescence, thermoluminescence, and photoluminescence among other characteristics. The uses of these properties have grown exponentially from recreational uses in luminescent paints, toys, plasticines, and other industry-specific uses, such as crack sensors, flaw detectors, and radiation meters in medicine. These uses have grown proportionately with their more economical and efficient manufacturing methods and processes, generating more economical fluorescent pigments. This paper characterizes and compares a low-cost luminescent pigment with those reported by different authors, its chemical composition was characterized by X-ray energy dispersion spectrometry, X-ray fluorescence, and Raman spectroscopy. Its morphology was analyzed by scanning electron microscopy, and its particle size with a laser meter its structural condition with X-ray diffraction, the powder obtained was presented as a strontium alumínate doped with divalent europium and trivalent dysprosium (Al2O4: Eu2+, Dy3+) one of the most efficient powders around persistence and luminance intensity at present. The structure of the strontium aluminate was determined by the main peaks of the diffractogram showing a monoclinic system. The elemental composition helped to determine the doping of the strontium aluminate corroborating them with the obtained with Raman spectroscopy and the scanning electron microscopy images.
Comparison of segmentation tools for structural analysis of bone tissues by finite elements
Authors: Argüello D , Sánchez Acevedo H G , González-Estrada O A 
Published: November 2019

Abstract
Medical image segmentation is one of the bases of development in the field of personalized medicine, which allows the reconstruction of parts of the human body to produce virtual models by classifying pixels to create a surface or volume with similar properties. This work is focused on image segmentation through open-source software for bone structure analysis using the finite element method. According to this approach, the aim of this study is to investigate the sequential process, based on the features and requirements of the reconstruction software, to assess the segmentation tools and provide a comparative analysis. The methodology focuses on the software that has been documented for the anatomical reconstruction of organs and tissues, accounting for algorithms of manual, semi-automatic and automatic handling. Three segmentation packages are analyzed: 3D Slicer with a semi-automatic process called Region Growing, ITK-Snap with its interactive mechanism Active Contour segmentation mode, and, finally, In Vesalius with its automatic segmentation technique that identifies types of tissues and a simplified user-machine interface. A comparison is proposed based on the ease of the workflow, time for completion, the robustness of the tool, and precision of the semi-automatic and automatic methods, as opposed to the manual process, by statistic deviations and volume error obtained with Cloud Compare. The segmentation of a vertebra obtained from a DICOM© file in a computerized axial tomography was completed, and performance indicators were evaluated. The results showed that 3D Slicer - Grow from seeds is the best option to make the segmentation with a 9.59% of volume error and the fastest process among others.
Modeling a helium atom from a collision of an electron with an ionized helium atom
Authors: Alcalá Varilla L A , Pérez Pitalua D L , Torres Hoyos F 
Published: November 2019

Abstract
A method which is based on quantum scattering theory and, particularly, on the Jost functions, is presented for solving the bound states problem of helium atom. Within this approach, the energies of bound states of helium atom were obtained as the sum of energies of a hydrogen atom and the energies that one electron needs to bind to an ionized helium atom in a collision process. We calculated the ground state energy and the energies of the first excited states of helium atom, and obtained remarkable results, This method could then be used as basis to study atoms with more electrons.
Spatial autoresonance acceleration physical scheme based on magnetic rings system
Authors: Orozco E A , Dugar-Zhabon V D , López J E , López J 
Published: November 2019

Abstract
The spatial auto-resonant acceleration scheme consists in the acceleration of an electrons beam by the transverse electric field component of a standing microwave field and an external inhomogeneous magnetostatic field, whose longitudinal profile is fitted to maintain the electron cyclotron resonance condition along of its helical trajectories. In practice, the external magnetic profile can be generated by a system of current coils. In order to save energy and the possibility to reduce space, we study the option to replace the coils by a magnetic rings system of uniform axial magnetization. In this work, we present both, the results of the magnetostatic field generated by a magnets system, which is calculated from the magnetization currents using the Biot-Savart law, and the acceleration of an electrons beam in the spatial auto-resonant acceleration regime employing said magnetostatic field. The electron trajectory, its velocity and energy are obtained from the numerical solution of the relativistic Newton-Lorentz equation, showing that is possible to accelerate electrons injected with energies about of some electronvolts to values about of 250 keV.
Numerical simulation of fast ions guiding-center orbits in mega ampere spherical tokamak-reactor configuration
Authors: López J E , Orozco E A , Dugar-Zhabon V D , Cárdenas P A 
Published: November 2019

Abstract
Determining the charged particle trajectories in the inhomogeneous electric and magnetic fields is the common problem in the plasma physics. For the tokamak plasma, the orbits of the captured fast ions are affected both by the curvature and gradient of the magnetic field. In the present work, the fast ion trajectories and their guiding-centre orbits in a mega ampere spherical tokamak reactor are found with employing the numerical code, that was elaborated by our team, together with the leap-frog and Runge-Kutta techniques. The magnetic field is calculated by solving the Grad-Shafranov equation at the fixed boundaries on the non-homogeneous mesh grid. The obtained results show that the ions with the energies in the range 20 keV - 80 keV can describe the typical banana orbits as well as the passing trajectories in the poloidal plane. Finally, the numerical simulation scheme stability is tested.
Comparative thermal analysis of extruded ceramic products between multi perforated brick and modified bricks in cells distribution
Authors: Colmenares A P , Sánchez J , Díaz C X 
Published: November 2019

Abstract
The demand for cooling and heating systems to adapt spaces is a critical environmental problem due to the high energy consumption required for its operation. For this reason, the offer of products for architectural facades should consider constructive solutions that mitigate the heating of buildings. Thermal behavior of building materials is an elementary factor in the energy consumption of buildings. This paper presents the comparative thermal analysis of 4 ceramic product designs for masonry, of which, one represents the traditional multi perforated brick and the others, are proposed to prove whether shape affects the heat transfer processes. The research methodology is divided into 2 stages: product design and thermal validation by transfer and heat fluxes in the ANSYS R16 software using the finite element method. For the design process, modification of the internal cells and elimination of the thermal bridge was implemented. Simulations were configured under the highest values of solar radiation recorded in the city of San José de Cúcuta, Colombia to know the products performance in the most extreme conditions of the city. The results indicate that design varies energy performance of the product, since it reduces the temperature of the inner surface to 1.23 °C or increase it to 2.25 °C. The results show that the modification of cells distribution and elimination of thermal bridges are passive strategies for the reduction of heat transfer in the design of ceramic product for masonry. This research is a breakthrough for future research that develops constructive units focused on improving the quality of life of people from thermal comfort, energy efficiency and the use of local resources and technologies.
A numerical model of the behavior of the resistance to compression in prisms of solid masonry
Authors: Afanador García N , Farelo Alvarez K A , Calderon F 
Published: November 2019

Abstract
This research work presents an experimental and numerical analysis of three-dimensional behavior to the compression of masonry prisms with solid brick, in pieces built-in artisanal ovens used in the municipality of Ocaña, Colombia, with the objective to determining deterministically the resistance to uniaxial compression and determine numerical models for structural design purposes. The experimental methodology consisted of determining statistically for solid clay brick units, the initial rate of absorption, final absorption, rupture modulus and resistance to uniaxial compression, and in masonry prisms, to uniaxial compression resistance and modulus of elasticity. The behavior observed in the uniaxial compression test in masonry prisms were validated in a commercial code of finite element modeling. The efficiency of the model makes it possible to predict the uniaxial compressive strength of masonry prisms in solid bricks built in artisan ovens. Allowing to reduce the number of tests in the future and perform probabilistic analysis.
Implementation of research agendas in the training of engineers: Academic training with social sense
Authors: Bohórquez Chacón L F , Avendaño M A 
Published: November 2019

Abstract
The implementation of research intervention strategies is presented as the main theme of this longitudinal study, within the framework of the application of the research agenda of engineering programs. Classroom work, training practices, business practices, classroom projects, and research group projects are proposed as training scenarios. The strategies are actions that are applied in three productive processes of interest for the engineering, such as: (i) productive process of object systems (ii) primary biomass productive process and (iii) primary artisanal cosmetics production process. The objective is to show the results of the research agendas application as an academic process planning tool for form research competencies. Three cases have presented that show the knowledge construction and the research intervention traceability in different the engineer fields in his training process. The three production processes become application centers of an area of the engineer research interest, as is the supply chain optimization. In the results, the planning methods of the agenda highlight, with the collective construction of knowledge of the training process, the targeting of the area of research interest, the linking of actors, the articulation of research lines of the program, and the scope of the strategies of intervention and didactics by scenarios. The study shows training relevant processes in the economic, social and environmental fields, promoting collective learning opportunities and fostering innovation through inclusive industrialization.
Good practice guide around the security of the internet of things in smart homes
Authors: Sánchez-Pérez L M , Velásquez-Pérez T , Camargo-Pérez J C 
Published: November 2019

Abstract
This article presents a guide to good practices around internet safety of things for devices that get involved with smart homes. It is chosen to use a quantitative methodology of descriptive approach, taking into account that it is a topic that is in incursion and it is necessary to begin to establish the elements that are going to incorporate in the guide. The starting point is a study of the internet layers of things, the open web application security project and the components that make up the guide. This research allows to make a contribution with an analysis of the future of the internet of things and to expose the considerations on the security that involve these devices, taking as guide the tools, documents and information that the project proposes for the development of systems of high quality in security.
Effects of climate change on the resources of the rural ecosystem, a view from farmer perspectives
Authors: Núñez R J J 
Published: November 2019

Abstract
This paper presents the results obtained from the categorization of the social representations of farmer groups on the effects of climate change on the biodiversity of their farms, developed in a rural area of the Colombian Andes. A mixed methodology was used throughout the analysis of the behavior of rainfall and temperature between the years 2010-2017 and the implementation of an open survey on 144 farmers, of which its data was analyzed using descriptive and inferential statistics through descriptive estimators and an analysis of variance and multiple comparison mean tests, respectively. Furthermore, a qualitative analysis, supported by Corbin and Strauss’ Grounded Theory, was carried out on 18 farmer families using semi-structured interviews. The hypothesis testing determined the existence of significant differences between the mean temperatures of the years observed when obtaining a value of Fc = 3.50, highly significant at 1%, and a value of Fc = 2.79, significant at 5%, P<0.05, for the mean rainfall. In the descriptive analysis, farmers’ perception of the negative effects of climate change was evident in the decrease in the availability of water from natural sources (80.6%), deterioration in water quality (50.0%), variations in rainfall intensity (82.0%) and in local bimodal rainfall patterns (79.0%). The inferential analysis determined that the proportion of farmers reporting a disappearance of species due to intense heat or rainfall differs significantly from the level of p<0.05, over those who reported that these conditions have not caused variations in flora and fauna. The qualitative analysis verified the effects of climate change on rural biodiversity resources, which were expressed in 4 emerging categories: 1) Biodiversity resources in the process of extinction, 2) resilient resources, 3) emerging biodiversity, and 4) new agricultural business opportunities. The findings reveal that from a farmers’ perspective climatic variations are affecting species of fauna and flora in rural communities.
Unidirectional motion of magnetic domain walls: the experiment and numerical simulation
Authors: Pamyatnykh L A , Lysov M S , Pamyatnykh S E , Mekhonoshin D S , Agafonov L Yu , Shmatov G A 
Published: November 2019

Abstract
The results of study of unidirectional motion of topologically different domain structures under the influence of periodic bipolar and unipolar magnetic field pulses applied perpendicular to the sample plane of (111) iron garnet single crystal plate are presented. The response of the domain structure to the field pulses was studied by direct observations utilizing the stroboscopic technique. Experimentally obtained dependences of the speed of unidirectional motion of stripe domains on the parameters of external bipolar pulsed magnetic field are compared with the results of numerical simulations.
One-dimensional dynamics of magnetic inhomogeneities in a three- and five-layer ferromagnetic structure with different values of the magnetic parameters
Authors: Gumerov A M , Ekomasov E G , Kudryavtsev R V 
Published: November 2019

Abstract
The article presents the research results of localized magnetization waves dynamics in five-layer and three-layer ferromagnetic structures. Structures consisting of three or two wide identical magnetic layers separated by two or one thin magnetic layer with the magnetic parameters values changed relative to wide layers are considered. The magnetic anisotropy, exchange, and damping parameters are considered to be the functions of the coordinate perpendicular to the interfaces. Intermediate layers are assumed to be infinitely thin. The considered magnetic material has homogeneous magnetic parameters everywhere, except for the planes corresponding to the interlayers. Using the approximate collective-coordinate method, the dynamics of coupled nonlinear magnetization waves localized on thin layers is theoretically studied.
Dynamics of magnetization in an array of three-layer nanodiscs
Authors: Orlov V A , Patrin G S , Orlova I N 
Published: November 2019

Abstract
The paper studies associated motion of magnetic vortices in a triple-layer FM/NM/FM disc array. The connection of magnetic layers’ magnetization inside of one disc and between the discs is assured by magnetostatic interaction. The frequencies of magnetic vortex resonant motion have been calculated analytically and resonant curves for the arrays with different alternation of magnetic vortex polarity and chirality have been constructed. It has been shown that despite of a small value of the core magnetic moments, taking their interaction into account leads to a small but significant splitting of the resonant frequency.
Frustrations and orderings in Ising chain with multiple interactions
Authors: Zarubin A V , Kassan-Ogly F A , Proshkin A I 
Published: November 2019

Abstract
The frustration properties of the Ising model on a one-dimensional monoatomic equidistant lattice are investigated taking into account the exchange interactions of atomic spins at the sites of the first (nearest), second (next-nearest) and third neighbors. The exact solution of the model was obtained using the Kramers–Wannier transfer matrix method. The types of magnetic ordering of the ground state of the model are determined, and a magnetic phase diagram is constructed. Criteria are formulated for the occurrence of magnetic frustrations in the presence of competition between the energies of exchange interactions. Non-zero entropy values in the ground state of the frustrated system were found.
Phase transitions in the two-dimensional four-vertex Potts model with quenched nonmagnetic impurities
Authors: Babaev A B , Murtazaev A K 
Published: November 2019

Abstract
The thermodynamic properties and phase transitions in the two-dimensional weakly diluted Potts model with the number of spin states q=4 were studied by the Monte Carlo method. Systems with linear dimensions L×L = N, L=10–160 are considered. Using the fourth order Binder cumulant method, critical temperatures were calculated for spin systems with a spin concentration p=1.0 and 0.90. Critical indices are calculated on the basis of the theory of finite-size scaling. The universality of the critical behavior of two-dimensional disordered systems is discussed.