bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultralow Emittance Thermal Radiation Barrier Achieved by a High-Contrast Grating Coating
Authors: Zhang Richard Z. , Araki Ken
Published: August 2022

Thermal radiative emission in vacuum is minimized using metal-backed flexible “space blankets” that have a theoretical minimum infrared emittance of 0.03. However, their presence under oxygenated and degradation-prone environments rapidly increases emittance due to metal oxidation, surface pitting, and implantation of contaminants. A monolithic dielectric coating composed of microscale periodic metasurface gratings on multilayers and metal thin film can achieve sub-1% total emittance. The minimum emittance can be tailored to any temperature-function blackbody emission, so long as the selected dielectric coating materials have near-zero absorption. Using computational optimization and theoretical understanding of high-contrast grating phase-shift mode conditions, we identified characteristic at-wavelength germanium gratings and a near-quarter-wave layer above a low-refractive-index infrared-transparent Fabry–Pérot multilayer interference cavity. This dual mechanism can achieve a room-temperature total emittance of 0.0085, paving a new theoretical minimum multilayer insulation effective conductance. As multilayer insulation, this coating offers total effective emittance of 0.0032 per pair of optimally mismatched grating surfaces. This ultrahigh reflection coating design can also be relevant in thermal management of refrigeration and electronic components.
PERFORMANCE OF PHP CRUD WEB SERVICES WHEN WORKING WITH POSTGRESQL DATA
Authors:   Zaporizhzhia Polytechnic National University, Tochilin Sergei
Published: August 2022

When developing modern distributed computer systems that work with DBMS data, a service-oriented architecture is widely used. For the practical implementation of such systems, Web services are used, which are developed using various technologies.At the same time, the performance of a Web service largely determines the possibility of its use in a distributed system.PHP tools provide an efficient platform for building Web services that support various technologies.PostgreSQL is one of the most common and productive DBMS. The performance of XML-RPC, SOAP and RESTful PHP Web services when searching PostgreSQL data, i.e. when performing a CRUD read operation, has been explored before.At that time, similar studies for XML-RPC, SOAP and RESTful PHP Web services in the implementation of CRUD oper-ations to create, update and delete PostgreSQL data were not made.In this work, PHP CRUD Web services were developed to work with PostgreSQL data in the amount of 1 MB, as well as a tester program that evaluates their performance based on determining the response time when making Web requests.With the help of the created programs, the analysis of performance of XML-RPC, SOAP and RESTfulPHP CRUD Web services at work with PostgreSQL data is carried out.The SOAP Web service had the highest response time when performing create, read, update, and delete operations on DBMS data, the XML-RPC service had the average, and the RESTful service had the lowest (best performance).The results obtained indicate both the significant impact of service development technology on its performance, and the advisability of using RESTful Web services when creating applications with a service-oriented architecture for working with PostgreSQL DBMS data using CRUD operations.
DEVELOPMENT OF SPECIAL MATHEMATICAL MODELS FOR RESEARCH OF ACCURACY OF REAL SURFACES OF TEETH WHEELS OF CYCLOIDAL TRANSMISSIONS
Authors:   National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Strutynskyi Serhii , Semenchuk Roman ,   National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”
Published: August 2022

Promising areas for improving robotic systems based on cycloidal gears aimedto increase their accuracy and other performance characteristics. The accuracy of the rotary unit and the mechanism as a whole is determined by errors in the manufacture of the transmission. Integral quantities are not enough to assess the accuracy of the transmission wheels. To determine the errors of the geometry of parts requires a technique that includes modeling of its real surface. The cyclic nature of the curve that defines the generating surface of the wheel allows the use of optimized mathematical models based on Fourier series. The technique allows for accurate processing of experimentaldata and compare them with the theoretical profile. Approbation of the concept requires modeling of the theoretical profile and research of the manufactured parts. The method allows to determine the parameters of the wheels by analyzing the differences between the simulated surface of the part and the theoretical profile. A hole in the part can be used as a base surface in the manufacture. Determination of the surface profile of the transmission wheel is carried out on a coordinate measuring machine, which allows to get a set of points. Surface modeling by discrete values is performed by spline interpolation. In the future, the description of the surface is performed using harmonic functions. The proposed mathematical apparatus allows the use of spectral analysis tools and statistical methods. The harmonic series is obtained by means of the Fourier transform. Monte Carlo methods allow to compare the mathematical model of the real profile of the mechanical transmission wheel and the theoretical surface. This makes it possible to take into account the presence of eccentricity, phase shift and other features of the part when determining the accuracy parameters. The mathematical model allows to effectively use experimental data in determining the characteristics of the surface of the part. The use of stochastic parameters in modeling makes it possible to take into account the accuracy of the wheel and increase the accuracy of determining the parameters of mechanical transmission.
Constructive algorithms for forming compound cubic Bezier curves in space and on plane
Authors:   South Ural State University (National Research University), Korotkii V. A.
Published: August 2022

The article considers two graph-analytical algorithms. The first algorithm makes it possible to form a spatial curve passing through given nodal points with direction vectors specified at these points. The second algorithm allows you to generate a flat compound curve passing through the given nodal points with direction vectors and curvature radii specified at these points. The constructed curves are formed by cubic Bezier segments. Direction vectors are treated as a control for the shape of the curve being constructed. At the nodal points, second-order geometric smoothness is ensured, due to the continuity of the slope and curvature. A distinctive feature of the proposed algorithms is the significant use of constructive means of computer graphics.
Calibration of double electroinduction spherical electric field strength sensor in a homogeneous field
Authors:   Omsk State Technical University, Biryukov S. V. , Tyukina L. V. ,   Omsk State Technical University, Tyukin A. V. ,   Siberian State Automobile and Highway University
Published: August 2022

For measuring the strength of electric fields near highvoltage equipment, dual electroinduction spherical sensors, which are a constructive combination of two double sensors into one, are promising. Before operation of the sensors, they must be calibrated in a homogeneous ED. This process is time consuming, expensive and not safe. In the paper, the authors propose the idea of calibrating sensors with currents equivalent to the output currents of a sensor located in a real uniform field. For this, a current signal simulator has been developed, which is based on mathematical relationships obtained during the theoretical interaction of a sensor with a homogeneous ED. To test the proposed idea, the dual sensor is first tuned and calibrated according to the method described in the article to obtain static characteristics. Then, to confirm the correctness of the calibration, the sensor is placed in a real homogeneous electric field. In a homogeneous EC, static characteristics are taken from the sensor and compared with its static characteristics obtained after the current signal simulator. The results of the comparison showed a good match of the static characteristics. The discrepancy is no more than ±3 %. Since the experiments are carried out for evaluation, such an agreement of the static characteristics can be considered acceptable. A more careful adjustment of the measuring circuits of the dual sensor will reduce the error of the discrepancy between the static characteristics to (0,5–1) %. The obtained results of the research allow us to confirm the adequacy of the theory underlying the calculations of dual electric induction sensors of the electric field strength.
On the issue of achieving subpicometric resolution by acousto-optic two-channel laser displacement interferometer with two different frequency photodetectors
Authors:   Lavochkin Association, Leun E. V.
Published: August 2022

The article discusses an acousto-optical (AO) heterodyne laser displacement interferometer (LDI) with two different-frequency photodetectors: highfrequency (HF) and low-frequency (LF) low-noise, working with «fast inaccurate» and «slow accurate» measuring channels, respectively. The mode of operation of AO LDI at start-stop cyclic motions of objects is described, which provides high resolution at the initial and final stages of motions with low speeds of motion. A metrological analysis of the «slow accurate» channel is carried out taking into account the noise frequency characteristics of photodetectors with the formation of its so-called «optimistic» and «pessimistic» variants. Based on the metrological analysis carried out, the frequency ranges of the signal are determined, which allow achieving the resolution of AO LDI subpicometric values at low speeds.
Study of changes in color characteristics of steel under thermal exposure
Authors:   Siberian Fire and Rescue Academy EMERCOM of Russia, Gorbunov A. S. , Elfimova M. V. ,   Siberian Fire and Rescue Academy EMERCOM of Russia, Bezborodov Y. N. ,   Siberian Fire and Rescue Academy EMERCOM of Russia
Published: August 2022

The article presents the results of studies of steel samples under thermal exposure, by measuring color characteristics using a model of color decomposition into RGB components. The data obtained can be used in the investigation of fires at objects made of steel building structures and objects made of steel. Thus, the specialist will be able to confirm his conclusions regarding the establishment of the source of the fire and the ways of its spread.
The hardware and software complex for electromechanical equipment diagnostic
Authors:   Omsk State Technical University, Gordeev O. I. , Zakharenko V. A. ,   Omsk State Technical University
Published: August 2022

The results of the development of the hardware and software complex for electromechanical equipment diagnostic by electrical power consumption parameters are presented. The connection of the prototype of the above-mentioned complex to the laboratory stand for vibration diagnostics of electromechanical equipment and the obtained possibilities for experimental research are described. The obtained experimental graphs of changes in the values of the main electrical power consumption parameters of the electric motor over time at different levels of load on the shaft of the stand are shown.
Development of grease resistant to water washout
Authors:   Omsk State Technical University, Pashukevich S. V.
Published: August 2022

In the work, laboratory tests are carried out to create a grease with the introduction of waterproof components into the composition with further analysis of samples of the resulting lubricant. A technique has also been developed to measure the washout of greases. During the tests, the values of the following technological properties of greases are obtained: dropping point, penetration at 25 °C with stirring, colloidal stability, welding load, washout, freezing point, tensile strength at 20 °C and at 80 °C. A comparative analysis of each of the considered indicators of five samples of the developed lubricant and samples of already manufactured products are carried out.
Evaluating possibility of creating modular DC/DC power supplies with configurable structure
Authors:   Saint Petersburg Mining University, Shpenst V. A. , Orel E. A. ,   Saint Petersburg Mining University
Published: August 2022

The paper deals with the problem of creating power supplies for autonomous electrical complexes. The paper demonstrates that the lifetime and efficiency of their operation can be improved by using two fundamental principles: modular construction of the system and intellectual principles of its operation. The article proposes the idea of creating a configurable power supply with power range up to 10 kW, consisting of typical, mass-produced power modules forming together a structure MN, where it is possible to change their interconnections and perform current and voltage control of each module.
The analysis of development of oil-free bearing systems of high-speed compressor and rotary-type power units for mobile operating conditions
Authors:   Omsk State Technical University, Raykovskiy N. A.
Published: August 2022

The article considers an analysis of prospects for the use of oil-free bearings for working conditions in rotary units of autonomous mobile installations. The analysis made it possible to establish the current level of development of oil-free bearing technologies, the existing limitations of their use in units of autonomous mobile installations and urgent problems, the solution of which requires research and further improvement of the designs of bearing units.
I. Costanzo, S. Murgia, G. Valenti, F. Fasani. Experimental investigation on a sliding-vane expander for steam applications / trans. from Engl. M. A. Fedorova
Authors:   Omsk State Technical University, Fedorova M. A.
Published: August 2022

There are many industrial plants that use steam as an energy vector at different pressure levels, in which pressure reduction is commonly performed by a throttling valve, resulting a totally irreversible process. It is possible to recover this energy through an expander that generates mechanical or electric energy. This work is focused on the analysis of a highly innovative steam expander based on sliding-vane technology. The design principles of the sliding-vane expander and two experimental campaigns are presented. The first experimental campaign allows to assess the reliability of the system with steam as working fluid, the second campaign leads to assess the stability during long-run and the performance of the system. A maximum expander mechanical power of 28 kW is measured. The pressure-volume diagram of the expansion process is also measured and presented.
Velocity coefficient of tangential supply of subsonic centripetal turbine
Authors:   Reshetnev Siberian State University of Science and Technology, Kishkin A. A. , Delkov A. V. ,   Reshetnev Siberian State University of Science and Technology, Shevchenko Yu. N. ,   Reshetnev Siberian State University of Science and Technology, Abdullaev M. U. ,   Reshetnev Siberian State University of Science and Technology
Published: August 2022

Today, in the spectrum of tasks solved by orbital spacecraft, there is a direction associated with an increase in both functional and thermal power radiated by the thermal control system into outer space. At thermal power more than 7 kW, there is a shortage of heat-radiating surfaces. The problem can be solved in three directions: increasing the temperature of the radiating surface; unfolding additional surfaces; utilization of thermal energy in the organic Rankine cycle. The key link in the implementation of the cycle is the modeling and design of a low-potential jet microturbine. When modeling the working process of such a turbine, a preliminary assessment of energy losses during the formation of a circumferential flow at the impeller inlet is necessary. One of the parameters determining part of the losses is the velocity coefficient φu . This work is devoted to the theoretical substantiation and method of experimental determination of the coefficient in the range of geometric and regime parameters of the tangential supply of a subsonic centripetal turbine.
Centrifugal compressors of turboexpander units: development of approaches and experience of optimal design
Authors:   Peter the Great St. Petersburg Polytechnic University, Galerkin Yu. B. , Rekstin A. F. ,   Peter the Great St. Petersburg Polytechnic University, Semenovskiy V. B. ,   Peter the Great St. Petersburg Polytechnic University, Marenina L. N. ,   Peter the Great St. Petersburg Polytechnic University, Solovyeva O. A. ,   Peter the Great St. Petersburg Polytechnic University, Drozdov A. A. ,   Peter the Great St. Petersburg Polytechnic University, Rozanov L. N. ,   Peter the Great St. Petersburg Polytechnic University, Brodnev P. N. ,   Peter the Great St. Petersburg Polytechnic University
Published: August 2022

The process of designing a new turboexpander unit using the Universal modeling method consists of several stages: preliminary design, optimization, calculation of gas dynamic characteristics. The development of modern computational methods and the accumulation of experimental research results has allowed to improve mathematical models in the field of calculation and design of CC turbo-expander units. The resulting model includes 22 empirical coefficients, the calculation error is 1,8 %, which is sufficient for its practical application in project activities.
The problem of ensuring requirements for microaccelerations on board of small spacecraft
Authors:   Samara National Research University, Sedelnikov A. V. , Eskina E. V. ,   Samara National Research University, Taneeva A. S. ,   Samara National Research University, Khnyryova E. S. ,   Samara National Research University, Matveeva E. S. ,   Samara National Research University
Published: August 2022

The paper provides an overview of ways to reduce micro-accelerations in the internal environment of a small spacecraft and provides quantitative estimates of the level micro-accelerations. The design image of a small technological spacecraft is being formed. The issues of ensuring the quality of the obtained results of gravity-sensitive processes by monitoring the level of micro-accelerations on board small spacecraft are considered. The results obtained can be used in the design and operation of small spacecraft for technological purposes.
The analysis of features of occurrence of inertial explosion in problems of high-speed impact of metal penetrators into the studied celestial body and meteor-technogenic particles into elements of spacecraft
Authors:   Lavochkin Association, Leun E. V. , Dobriza D. B. ,   Lavochkin Association, Poliakov А. А. ,   Lavochkin Association, Sysoev V. К. ,   Lavochkin Association
Published: August 2022

The article discusses the features of the occurrence of an inertial explosion (IE) in the problems of high-speed impacts on a solid barrier of two types of impactors: metal penetrators into the studied celestial body for space contact scientific research and meteor-technogenic particles into the elements of spacecraft. The features of IE, the conditions of its occurrence and the results of theoretical and experimental studies are analyzed. The ratio of the calculated impact velocity, leading to the appearance of willows, to the speed of sound in different metals tending to a certain average value is discussed. The influence of contact and thermoelectric phenomena and the temperature of the impactor on the occurrence of IE, as well as its dependence on the cross-sectional area of the impactor, is discussed. The ways of preventing the occurrence of IE are considered.
The Effects of Drying Methods on the Physico-chemical Properties and Antioxidant Activity of Bilimbi (Averrhoa bilimbi)
Authors: Sangalang Reygan H. , Baylon Jenalyn R. , Cajefe Alida Joy V. , Valencia Jenna Mariz S.
Published: August 2022

Bilimbi (Averrhoa bilimbi) is an underutilized fruit usually grown in tropical countries and is widely added as souring agent in many Filipino dishes. However, it is undervalued and its utilization is limited due to short shelf life. Drying is one of the more popular and cheapest means of prolonging its storage life. This study aimed to investigate the effects of drying methods on the physicochemical properties and antioxidant activity of bilimbi. Analysis of proximate composition, pH, total sugar, ascorbic acid content, oxalic acid content and antioxidant activity was conducted on the fresh and dried fruit samples. Data showed that drying significantly affected the proximate composition and pH of bilimbi (p < 0.05). The oxalic acid content, total sugar content and antioxidant activity of dried bilimbi generally increased while significant loss in ascorbic acid was observed in solar dried and oven dried bilimbi. Freeze drying removed the most amount of moisture while preventing significant decrease in ascorbic acid level in bilimbi. Dried bilimbi is a good source of macronutrients, ascorbic acid and possessed good antioxidant activity regardless of the method of drying utilized.
Boronated Cyanometallates
Authors: McNicholas Brendon , Nie Cherish , Jose Anex , Oyala Paul , Takase Michael , Henling Larry , Barth Alexandra , Amaolo Alessio , Hadt Ryan , Solomon Edward , Winkler Jay , Gray Harry , Despagnet-Ayoub Emmanuelle
Published: August 2022

Thirteen boronated cyanometallates [M(CN-BR3)6]3/4/5– (M = Cr, Mn, Fe, Ru, Os; BR3 = BPh3, B(2,4,6,-F3C6H2)3, B(C6F5)3) and one boratonitrile [Cr(NC-BPh3)6]3– have been characterized by X-ray crystallography and spectroscopy [UV-vis-NIR, NMR, IR, spectroelectrochemistry, and magnetic circular dichroism (MCD)]; CASSCF+NEVPT2 methods were employed in calculations of electronic structures. For (t2g)5 electronic configurations, the lowest energy ligand-to-metal charge transfer (LMCT) absorptions and MCD C-terms in the spectra of boronated species have been assigned to transitions from cyanide σ+π + B-C borane σ orbitals. CASSCF+NEVPT2 cal-culations including t1u and t2u orbitals reproduced t1u/t2u → t2g excitation energies. All [M(CN-BR3)6]3/4− complexes exhibited highly electrochemically reversible redox couples. Notably, the formal potentials of all five [M(CN-B(C6F5)3)6]3− anions scale with LMCT energies, and Mn(I) and Cr(II) compounds, (K(18-crown-6))5[Mn(CN-B(C6F5)3)6] and (TBA)4[Cr(CN-B(C6F5)3)6], are surprisingly stable. Continuous wave and pulsed electron paramagnetic resonance (hyperfine sublevel correlation) spectra were collected for all Cr(III) complexes; as expected, 14N hyperfine splittings are greater for (Ph4As)3[Cr(NC-BPh3)6] than for (Ph4As)3[Cr(CN-BPh3)6].
Exposing the limitations of molecular machine learning with activity cliffs.
Authors: van Tilborg Derek , Alenicheva Alisa , Grisoni Francesca
Published: August 2022

Machine learning has become a crucial tool in drug discovery and chemistry at large, e.g., to predict molecular properties, such as bioactivity, with high accuracy. However, activity cliffs – pairs of molecules that are highly similar in their structure but exhibit large differences in potency – have been underinvestigated for their effect on model performance. Not only are these edge cases informative for molecule discovery and optimization, but models that are well-equipped to accurately predict the potency of activity cliffs have an increased potential for prospective applications. Our work aims to fill the current knowledge gap on best-practice machine learning methods in the presence of activity cliffs. We benchmarked a total of 720 machine and deep learning models on curated bioactivity data from 30 macromolecular targets for their performance on activity cliff compounds. While all methods struggled in the presence of activity cliffs, machine learning approaches based on molecular descriptors outperformed more complex deep learning methods. Our findings highlight large case-by-case differences in performance, advocating for (a) the inclusion of dedicated “activity-cliff-centered” metrics during model development and evaluation, and (b) the development of novel algorithms to better predict the properties of activity cliffs. To this end, the methods, metrics, and results of this study have been encapsulated into an open-access benchmarking platform named MoleculeACE (Activity Cliff Estimation, available on GitHub at: https://github.com/molML/MoleculeACE). MoleculeACE is designed to steer the community towards addressing the pressing but overlooked limitation of molecular machine learning models posed by activity cliffs.
Spacer Switched Two Dimensional Tin Bromide Perovskites Leading to Ambient Stable Near Unity Photoluminescence Quantum Yield
Authors: MANDAL ARNAB , ROY SAMRAT , MONDAL ANAMIKA , PAL BIPUL , BHATTACHARYYA SAYAN , Gupta Shresth
Published: August 2022

Semiconductor nanostructures with near-unity photoluminescence quantum yields (PLQYs) are imperative for light-emitting diodes and display devices.A PLQY of 99.7±0.3% has been obtained by stabilizing 91% of the Sn2+ state in the Dion-Jacobson (8N8)SnBr4 (8N8-DJ) perovskite with 1,8 diaminooctane (8N8) interlayer spacer. The PLQY is favoredby a longerchain length of the hydrophobic spacer molecule, the extent of octahedral tilting and the preference of Sn2+at theB-site over Pb2+.The near-unity PLQY of 8N8-DJ has outstanding ambient stability under relative humidity (RH) of 55%for30 days throughout the entire excitation wavelength range, RH 75% for 3 days and 100°C for 3 h. By changing the spacer to n-octylamine (8N), Ruddlesden-Popper (8N)2SnBr4 (8N-RP) also has an appreciable PLQY of 91.7±0.6%, but having poor ambientstability due to increased lattice strain and structural degradation. The PL experiments from 5K to 300K decipher the room temperature PLQY to be due to the self-trapped excitons (STE) where the self-trapping depth is 25.6±0.4 meV below the conduction band as a result of strong carrier-phonon coupling. With 34.7-37.3meV exciton binding energy, the ~5.5 s long-lived STE emission dominates over the band edge (BE) peaks at lower excitation wavelengths and higher temperatures. The higher PLQY and stability of 8N8-DJ are due to the stronger interaction between SnBr64- octahedra and 1,8 diammonium octane cation leading to a more rigid structure. The near-unity PLQY of 8N8-DJ also remains unchanged from its powder form to the polymer-embedded perovskite films.
Electrostatic Embedding of Machine Learning Potentials
Authors: Zinovjev Kirill
Published: August 2022

This work presents a variant of an electrostatic embedding scheme that allows the embedding of arbitrary machine learned potentials trained on molecular systems in vacuo. The scheme is based on physically motivated models of electronic density and polarizability, resulting in a generic model without relying on an exhaustive training set. The scheme only requires in vacuo single point QM calculations to provide training densities and molecular dipolar polarizabilities. As an example, the scheme is applied to create an embedding model for the QM7 dataset using Gaussian Process Regression with only 445 reference atomic environments. The model was tested on SARS-CoV-2 protease complex with PF-00835231, resulting in predicted embedding energy RMSE of 2 kcal/mol, compared to explicit DFT/MM calculations.
Low-toxicity Chemical Solution Deposition of Ferroelectric Ca:HfO2
Authors: Badillo Miguel , Taleb Sepide , Mokabber Taraneh , Rieck Jan , Castanedo-Perez Rebeca , Torres-Delgado Gerardo , Noheda Beatriz , Acuautla Monica
Published: August 2022

So far, a few chemical solution routes for the fabrication of ferroelectric HfO2 films have been reported. Most of them employ precursors, solvents or additives that are considered difficult to handle, unstable, toxic, generally unfriendly with the environment and/or unsuitable for large scale industrial processes. In this work, we present a new effective chemical route for preparation of ferroelectric doped-HfO2 films. The solution is prepared from simple, stable, and available precursors, handled in an open atmosphere and requires no restrictive processing conditions. We used 5 at.% Ca as dopant of HfO2 to induce a maximum remnant polarization of 9.3 and 11.1 µC/cm2 for 54 and 90 nm thick Ca:HfO2 films, respectively. The current-electric field loops show intense and distinctive ferroelectric switching peaks and the corresponding ferroelectric loops show excellent saturation, which speaks of good device quality with low leakage. Crystallization and the wake-up of ferroelectricity in Ca:HfO2 films was attained by means of rapid thermal annealing at different temperatures and times in Ar:O2 atmosphere. In comparison to the thin films, thicker ones exhibited the highest remnant polarization at shorter annealing times, thus evidencing the need for precise control of thermal processing. The Ca:HfO2 films with thickness of 50 nm displayed a good balance between leakage and retention, maintaining the ferroelectric response above 105 cycles at 1 kHz. The developed precursor solution is promising for its use in spray-coating and ink-jet printing techniques.
MODELO DE ANÁLISIS CORRELACIONAL PARA LA IDENTIFICACIÓN DE PATRONES ASOCIADOS A LOS ACCIDENTES DE TRÁNSITO DE YOPAL
Authors: Ortegón Fuentes Ángela Bibiana , Castellom Rodríguez Juan David
Published: August 2022

Con el desarrollo del presente proyecto, se busca crear un modelo correlacional que permita identificar las características con mayor incidencia en los accidentes de tránsito en determinadas zonas de la ciudad de Yopal (Colombia), e indicar los patrones asociados a los mismos. En la construcción del modelo se aplican algoritmos de regresión lineal simple de aprendizaje supervisado, construyendo la correlación entre variables dependientes e independientes. El objetivo es obtener un modelo lineal que explique la relación entre las variables en toda la información de accidentes de tránsito en Yopal, calcular el coeficiente de determinación 𝑟𝑟2 y su significancia (p-value). El proyecto se lleva a cabo en cuatro fases: Construcción de aplicativo para la recolección de la información de los accidentes de tránsito según IPAT, medicina y Medicina Legal, en la segunda fase se identifican los diez puntos críticos de accidentalidad por georreferenciación, la tercera fase se caracteriza e identifica los factores de riesgos asociados a los accidentes de tránsito y cuarta fase, se Implementar Modelo Correlacional para la identificación de patrones asociados teniendo en cuenta la información recolectada en cada punto crítico Como resultado se verificó la existencia de correlaciones significativas entre la variables que intervienen en los accidentes de tránsito como fecha, gravedad, edad, día de la semana, grado de alcoholimetría y se relaciona con las variables independientes de precipitaciones meteorológicas tomadas del data set proporcionado por la Fuerza Aérea de Casanare, adicionalmente se identifican los puntos con mayor accidentalidad del municipio y los factores mas relevantes por cada punto, permitiendo a los entes involucrados identificar las causas raíces de los eventos, intervenirlos y evitar su reincidencia. Este proyecto se puede replicar en cualquier municipio de Colombia gracias al formato que se basa para la recolección (IPAT), documento reglamentado bajo la resolución 11268 de 2012 otorgada por el Ministerio de Transporte y se puede tomar de referente para la caracterización y correlación de los accidentes de tránsito a nivel mundial.
PROPUESTA DE LINEAMIENTOS DE ECONOMÍA CIRCULAR EN LAS ETAPAS DE GENERACIÓN Y ALMACENAMIENTO EN LA GIRS DOMICILIARIOS, BIODEGRADABLES Y PLÁSTICO, DEL BARRIO TABORA, BOGOTÁ D.C
Authors: Garzón Gabriela , Nieto López John Sebastián
Published: August 2022

La investigación desarrollada por ingenieros ambientales se enfoca en la propuesta de lineamientos de economía circular en las etapas de generación y almacenamiento en la Gestión Integral de Residuos Sólidos (GIRS) domiciliarios, biodegradables y plásticos, para el barrio Tabora, Bogotá D.C., Colombia. Esta propuesta surge inicialmente por la preocupación mundial en relación con la alta generación de residuos sólidos urbanos y sus efectos adversos, ya que no son separados ni aprovechados correctamente y son depositados en rellenos sanitarios. Esta problemática es identificada en el barrio Tabora, donde se generan residuos sólidos domiciliarios que no son separados en la fuente haciendo que se mezclen y pierdan su valor, su oportunidad de aprovecharlos para otro fin; entonces, todos estos residuos son considerados como basura. Tales bolsas son depositadas en las aceras y en los contenedores destinados al almacenamiento temporal donde se acumulan desbordándose del contenedor y/o dispersándose por las aceras liberando lixiviados, malos olores, y proliferando vectores como moscas y palomas. Incluso, es tan solo una muestra de la problemática en Bogotá a nivel social, ecológico y económico, ya que esa mezcla de residuos aprovechables y no aprovechables se disponen como basura en el Relleno Sanitario Doña Juana y se acumulan toneladas provenientes de todos los barrios de la ciudad. Por eso, es la mayor razón para proponer alternativas de solución desarrolladas desde la ingeniería. Por lo tanto, el proyecto de aplicación comienza con el diagnóstico de la gestión actual de los residuos, consistiendo en la recolección de información primaria y secundaria realizando recorridos y caracterización por cuarteo. Prosigue el análisis y contraste de información con casosde éxito de aprovechamiento de residuos biodegradables y de plástico para seleccionar la mejor alternativa aplicable al barrio Tabora. Así pues, se establecen los lineamientos de economía circular que puedan adaptarse al caso de estudio para crear valor, teniendo en cuenta los grupos de interés más representativos dentro de este sistema. Es así como se identifica que los tipos de residuos plásticos más generados en el barrio Tabora son el PP (polipropileno) y el PEAD (polietileno de alta densidad), bases de productos como paquetes de snacks y bolsas de supermercado; y se propone que se integren a la economía circular con los lineamientos: rechazar, reducir, reutilizar, repensar y reciclar, por medio de su aprovechamiento en materiales de construcción ecológicos y de artesanías Así mismo, se identifica que los tipos de residuos biodegradables generados en mayor cantidad son los restos de verduras y frutas, y se propone que se integren a la economía circular con los lineamientos: rechazar, reutilizar, y repensar, por medio de su aprovechamiento en compostaje y como materia prima para la alimentación de animales.
INFORMATION TECHNOLOGY AS A DRIVER OF ECONOMIC GROWTH
Authors: Shumilina Vera , Tupakova Ksenia
Published: August 2022

This article examines the opportunities for accelerating economic growth and labour productivity through the development and implementation of information and telecommunication technologies in the economy sector. The state of Russia's information technology (IT) market is analysed, and the problems of its development and prospective solutions are identified
METHODS AND APPROACHES TO ENSURE THE ECONOMIC SECURITY OF AN ENTERPRISE
Authors: Shumilina Vera , Popov Daniil
Published: August 2022

The article considers methods and approaches to ensure the economic security of the enterprise. It is necessary to apply a system of methods and mechanisms for ensuring economic security, the basis of which are general principles and criteria that contribute to the elimination of emerging threats and the development of strategic decisions that ensure the stability of the company
THE EFFECTIVE MANAGEMENT OF THE ENTERPRISE
Authors: Kuznecova Elena , Ishchenko Daria
Published: August 2022

The article considers the concept of effective enterprise management, indicators that should be analyzed in order to assess the effectiveness of management. The main aspects influencing the effective management of the enterprise are studied. The stages of building an effective management system are considered
Pengembangan Instrumen Eksplorasi Karir Remaja Menggunakan Analisis RASCH Model
Authors: Hikmy Bagus Julian , Supriatna Mamat , Yudha Eka Sakti
Published: August 2022

Eksplorasi karir merupakan aktivitas mencari informasi terkait pekerjaan. Untuk mengertahui gambaran  tingkat pemahaman eksplorasi karir siswa dapat diketahui dengan menggunakan instrumen. Akan tetapi, belum ada instrumen eksplorasi karir yang khusus dikembangkan untuk remaja. Penelitian ini bertujuan untuk mengembangkan dan memvalidasi instrument eksplorasi karir remaja dengan menggunakan analisis model RASCH. Partisipan dalam penelitian ini berjumlah 172 orang. Analisis data menggunakan RASCH model. Hasil penelitian menunjukkan bahwa dari 79 item pernyataan yang dikembangkan, item yang memenuhi standar pengukuran berjumlah 36 pernyataan. Sedangkan, hasil reabilitas item berada dalam kategori baik, reliabliitas person berada dalam kategori baik dan nilai cronbach’s alpha juga berada kategori sangat baik. Dengan kata lain, instrumen skala eksplorasi karir remaja memenuhi syarat pengukuran dan dapat digunakan untuk mengukur eksplorasi karir remaja.
Evaluación de la electrocoagulación con electrodos de grafito como alternativa para el tratamiento de aguas residuales en curtiembres
Authors: Agudelo V Rafael Nikolay , Garcés-Polo Siby I , Marca-Montoya Yesid M. , Peña-Giraldo Mauricio V.
Published: August 2022

En este trabajo se evaluó la electrocoagulación con electrodos de grafito como técnica avanzada para el tratamiento de agua residuales del proceso de depilado en curtiembres, con el objeto de reducir la turbiedad, carbono orgánico total y concentración de sulfuros en este tipo de efluentes. Las propiedades inertes del grafito ofrecen la ventaja de no generar la dilución de iones metálicos en el agua. En este sentido, se analizó el efecto del tiempo de reacción (30 min y 60 min), el número de electrodos de grafito (2 y 4) y la intensidad de corriente aplicada (12 A y 24 A) sobre el porcentaje de disminución o reducción de concentración de las variables mencionadas previamente. Para el desarrollo del proyecto se planteó un diseño experimental de tipo factorial 23. El volumen de agua para cada ensayo fue de 0.002 m3 y la temperatura del agua fue de 20 °C ± 2 °C. Las variables de respuesta para determinar la efectividad del proceso fueron el porcentaje de remoción de turbiedad, Carbono Orgánico Total y Demanda Química de Oxígeno. Los resultados experimentales fundamentados en el Análisis de Varianza permitieron establecer que los factores de proceso o variables experimentales seleccionadas influyen sobre los porcentajes de remoción de las variables de respuesta, además, se determinó que las condiciones de mayor remoción de sulfuros y turbiedad se lograron con 4 electrodos, 24 A y 60 minutos de tiempo de reacción, para esas condiciones la densidad de corriente aplicada fue de 107.14 A/m2. Los mayores porcentajes de remoción fueron 41.46 %, 75.02 % y 35.73 % para sulfuros, turbiedad y Carbono Orgánico Total respectivamente. Durante los ensayos no se observó desgaste en los electrodos y tampoco cambios de color en el agua.
Caracterización mecánica y determinación de la resistencia a la tracción de fibras de caña brava para uso en construcciones rurales
Authors: Vargas  Ortiz Nelson Joman , Villate Diaz Juan Pablo , Habran Esteban Nydia Margarita
Published: August 2022

Las técnicas usadas tradicionalmente para la construcción son evaluadas por normas y métodos de diseño en la ingeniería, las cuales se van actualizando diariamente para optimizar las propiedades estructurales y de los materiales. Sin embargo, el uso de materiales naturales está limitado por no contar con estudios necesarios y técnicas de conservación de los mismos y aún más por no contar con normatividad para su utilización en construcciones civiles, esto se ve reflejado en que las comunidades rurales no hacen uso de los materiales propios de su región para mejoramiento y adecuación de sus viviendas, por ello, en el presente estudio se pretende  investigar y dar resultados cuantitativos y cualitativos sobre las fibras de caña brava (gynerium sagittatum), esto con el objetivo de determinar si dichas fibras  pueden ser utilizadas y tener aplicaciones en el área de la construcción y mejoramiento  de viviendas en el sector rural. En este artículo podrá encontrarse la primera fase del proyecto en la cual se realizaron estudios de caracterización física empleando técnicas de microscopía óptica (MO) y microscopía de barredura electrónica (MEB), así como ensayos de resistencia mecánica de tracción y compresión, mediante los cuales fue posible determinar la resistencia del objeto en estudio
Uso de semillas del frijol común (Phaseolus vulgaris) para remover turbidez del agua residual doméstica
Authors: Rivera Cotrina Reyes , Flores Tauma Sheyka Malayma , Muñoz Delgado Víctor Hugo
Published: August 2022

La investigación se desarrolló con la finalidad de evaluar la eficiencia de las semillas de frijol común (Phaseolus vulgaris) para la eliminación de la turbidez de aguas residuales domésticas (ARD) como una tecnología de descontaminación de aguas residuales. Para ello, se seleccionó un diseño experimental (4 tratamientos y 3 repeticiones). Se utilizó un equipo prueba de jarras con 4 vasos de 1 L de capacidad cada uno. Los parámetros analizados de ARD fueron el pH y la turbidez. Los resultados muestran que con las dosis de 500 mg/L, 1000 mg/L y 1500 mg/L de coagulante de frijol los valores de pH fueron respectivamente 6, 5,93 y 6,12, mientras que con la dosis de 100 mg/L de sulfato de aluminio el pH fue 6,23. Los valores de pH bajos encontrados con el coagulante natural se relacionan con los valores bajos de turbidez, ya que existe una correlación positiva, es decir, cuando el valor del pH es menor, se esperan valores bajos de turbidez.
Asimismo, se encontraron porcentajes de eliminación de la turbidez del ARD más bajos con las dosis de 500 mg/L, 1000 mg/L y 1500 mg/L de coagulante de frijol, con valores 55,13%, 57,69% y 55,13%, respectivamente, sin que hubiera diferencia significativa entre las tres dosis; mientras que el porcentaje de eliminación de la turbidez fue mayor con la dosis de 100 mg/L de sulfato de aluminio (79,06%), siendo esta última mayor en 21,37% que con el coagulante natural. Al utilizar el coagulante proteico de frijol común para la eliminación de la turbidez de ARD, se encontró una eficiencia de remoción de turbidez de 72%. Se concluye que el uso del coagulante de las semillas de frijol es una alternativa accesible para remover la turbidez del agua residual doméstica.
Influencia de las características físicas en el comportamiento mecánico de los suelos granulares
Authors: Cordero Vargas Juan camilo , Manrique Paredes Jhon Sebastian , Moreno Quijano Oscar David
Published: August 2022

El objetivo de esta investigación es determinar cómo influyen las características físicas de los materiales granulares en su comportamiento mecánico. Para este caso se eligieron dos arenas nacionales las cuales son Guamo y Guayuriba y otra internacional que es Ottawa. Partiendo desde los ensayos de caracterización física se obtienen resultados de Cu, Gs, emin, emax, ρmin y ρmax, para determinar su efecto en los parámetros de resistencia, resultantes del ensayo de corte directo en condición consolidada drenada. La campaña experimental consta de 27 ensayos realizados a las 3 arenas para los esfuerzos verticales de 50 kPa, 100 kPa y 200 kPa con densidades relativas de 30%, 60% y 90% y una velocidad de corte de 1.0 mm/min. De esta manera se encontró la relación directa entre los valores físicos de ρr y las variables correspondientes a la resistencia al esfuerzo cortante máximo de (tmax), de ángulo de fricción (ϕ) y de cohesión.
Participar y gestionar la comunidad: ¿Utopía o distopía?
Authors: Juliao Vargas Carlos Germán , Zarta Rojas Fabián Andrey
Published: August 2022

Partiendo de la distinción que Tönnies realiza entre las categorías de comunidad y sociedad, y resaltando su valor teórico para el desarrollo, gestión, evaluación, perfeccionamiento, control y transferencia de los saberes y logrosalcanzados por ellas, abordamos la cuestión de la participación comunitaria y la gestión asociada. Dado el presupuesto teórico de Tönnies: “al comienzo fue la comunidad”, nos preguntamos si es factible participar y gestionar en las sociedades capitalistas actuales o si se requieren lazos comunitarios para una efectiva gestión asociada y una participación ciudadana pertinente, lo cual lleva a plantear la cuestión de si la gestión asociada es una utopía o una distopía. Todo ello solo resalta el papel fundamental que cumplen la situación, el contexto, el lugar, el territorio en lo político.
construcción social del territorio: un pretexto para la planificación comunitaria desde la experiencia medioambiental
Authors: Parra Cuestas Iovan
Published: August 2022

Este artículo de reflexión emerge del proceso de prácticas académicas y ejercicios de proyección social llevado a cabo en el marco de las acciones de planificación comunitaria en cuanto a la protección, cuidado y conservación de los recursos naturales y diferentes ecosistemas desarrolladas en el proyecto “Corredor de conservación Sumapaz, Chingaza, Guerrero”. Dichas acciones de planeación comunitaria, lideradas por la ONG Conservación Internacional Colombia, con el apoyo del programa de Trabajo Social de la Universidad Colegio Mayor de Cundinamarca (UCMC), han sido el pretexto para el cuidado de los ecosistemas y han permitido pensar y fortalecer la planificación comunitaria como un proceso social que emerge en la gestión de proyectos sociales, así como comprender la construcción de los territorios desde nuevas perspectivas y reconocer el rol fundamental de los sujetos que allí confluyen, en clave socioambiental.
Buenos Aires y el Río: Programa de Gestión Asociada mediante Consejos Participativos de Políticas Públicas (Ciudad Autónoma de Buenos Aires, 2002-2007)
Authors: Ramirez Natalia Eleonora
Published: August 2022

El gobierno de la Ciudad Autónoma de Buenos Aires[1] decidió en 1996 implementar una política pública que institucionalizó la participación ciudadana en su formulación y ejecución. Este trabajo pone en valor esta experiencia que ensayó una nueva forma de vinculación entre Estado y sociedad civil, implementando metodologías de planificación participativa y gestión asociada (PPGA), y generó proyectos que instalaron una mirada integral de la situación urbano-ambiental constituida como ribera. Incluye el contexto de la política pública, el modelo de gestión y funcionamiento de los consejos participativos de políticas públicas y muestra la relevancia ambiental de la ribera para un territorio urbano de la extensión y complejidad de Buenos Aires. Las conclusiones recuperarán la relevancia de este escenario como proceso social y político transformador. La experiencia fue relevante en lo social, puesto que se aumentó el área y las alternativas de uso recreativo para amplias comunidades, y en lo político, al dar cumplimiento al principio constitucional de la ciudad y ampliar la democracia a usuarios, comunidad en general y organizaciones sociales.
 
[1] En 1994 fue reformada la Constitución de la Nación Argentina y, como resultado de este proceso, la Capital Federal se convirtió en territorio autónomo.
Consejo Asociado Don José: relato de una experiencia
Authors: Fallacara Romina
Published: August 2022

En agosto del 2018, mediante trabajo conjunto entre la Municipalidad de Florencio Varela, la Universidad Arturo Jauretche y la Facultad Latinoamericana de Ciencias Sociales (FLACSO), se inició una experiencia de política pública con métodos de planificación participativa y gestión asociada (PPGA) en el barrio Don José. FLACSO brindaría una transferencia metodológica basada en prácticas de intersectorialidad, interdisciplina y consenso. La primera etapa se centró en la salud y en la niñez/adolescencia, y en la segunda, desarrollada durante la pandemia de covid-19, se intentó salvar el colectivo de trabajo, a través de la virtualidad. En la actualidad, los proyectos asociados se encuentran avanzando y fortaleciéndose para la postpandemia, mientras que se desarrollan acciones concretas para beneficiar a la comunidad donde el Consejo Asociado funciona.