bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Study of Heat Transfer Performance and Visualization Images of Superfluid Helium Boiling in Narrow Two-dimensional channel
Authors: Takada S. , Kobayashi H. , Murakami M. , Kimura N.
Published: June 2020

In a narrow channel, boiling heat transfer in He II is much different from that in the case of an open bath. Even under saturated pressure condition, rapid temperature rise due to the onset of film boiling is not seen when the temperature reaches the lambda temperature, but only the temperature oscillation is detected. The behaviour of this state looks like the nucleate boiling, though it is known the steady nucleate boiling state is absent in He II in open bath. The high heat transfer coefficient in this quasi-nucleation boiling state above the lambda temperature suggests the range where this advantage in heat transfer appears is wider than that based on simple prediction of He II heat transfer. The appearance of metastable states of superheated He II and superheated He I should be considered in the case of a narrow channel. In this study, the visualization experiment result using a transparent heater and the transient temperature measurement data on a copper heater surface had been compared with each other. In the case of rather high heat flux, several film boiling modes were observed in a narrow two-dimensional channel. The peak of the heat transfer coefficient appeared around the lambda pressure. In the case of low heat flux, the heat transfer coefficient variation with the pressure shows sudden rise around the lambda point. The heat transfer coefficient under nearly saturated pressure condition below the lambda pressure is larger than that above the lambda pressure.
Control and Commissioning of a Subcooled Helium Cryogenic Testing Platform with Cold Compressors
Authors: Zhou Z W , Zhang Q Y , Cheng A Y , Zhu P , Li S S , Zhu Z G
Published: June 2020

The subcooled helium cryogenic testing platform with cold compressors has been operated successfully in the end of 2018 at the Institute of Plasma Physics, Chinese Academy of Sciences (CASIPP). It is the first subcooled helium cryogenic system based on the cryogenic decompression technique in China, which has been designed and constructed over two years by our own team. The subcooled helium cryogenic testing platform was designed to provide the 4.5 K supercritical helium for the helium forced-flow cooling with one helium circulating pump, and provide the 3 K subcooled helium with two cold compressors in series. It consists of one 2.5 kW@4.5 K helium refregeator and one distribution valve box where the helium circulating pump and the cold compressors installed on it. This paper will present the process control flow of the distribution system and the design parameters of two cold compressors. During the commissioning, the startup and stop control flow of the two cold compressors have been determined. And their operation and control were performed within the safe operation area in the performance map. The testing result shows the lowest temperature and pressure of the saturated helium bath, and indicates the subcooled helium system has an equivalent refrigeration power greater than the design value of 700 W@3 K. The commissioning experience will help the reconstruction of the subcooled helium system for EAST Tokamak in future to enhance the cryogenic stability in higher magnetic field.
Cryogenic Upgrade of the Helium Central Liquefier and Superconducting Cable & Wire Test Facilities at CERN
Authors: Pirotte O , Lees A , Barbe T , Dupont T , Pezzetti M
Published: June 2020

The demand for liquid helium (LHe) for users at CERN without dedicated cryogenic infrastructure is set to increase due to future projects and experiments in the Antiproton Decelerator. LHe is supplied to the users by means of 500 liter dewars filled by the central liquefier (B165) that comprises a cryogenic plant of 400 W @ 4.5 K. In addition, the Superconducting Cable & Wire Test Facility (B163) located nearby will be upgraded to incorporate the forthcoming installation of the new test station FRESCA 2. B163 includes a second cryogenic plant of 400 W @ 4.5 K and a dedicated cryogenic distribution system. To maximize the production of the two cryogenic plants and their ancillary infrastructure, thus improving the subsequent distribution of LHe, a combined cryogenic distribution system has been developed. This system will increase the LHe storage capacity; allow the direct transfer of helium inventory between both facilities and the gravity filling of large capacity trailer dewars in addition to the 500 liter dewar fleet. This paper details the architecture of the new cryogenic distribution system, the analysis undertaken to define it, the design and specifications of the various components and the schedule of the realization of the project.
Compact cryogenic test stand for superconducting magnets characterization
Authors: Bruce Romain , Soulerin Sacha , Bouziat Denis , Cubizolles Robin , Gastineau Bernard , Juster François-Paul , Bredy Philippe
Published: June 2020

A new compact experimental facility for testing compact superconducting magnets down to 4.2 K using cryogenic fluids has been developed at CEA Paris-Saclay. This facility has been constructed to test the solenoid magnets for the next Soreq particle accelerator (SARAF) project. The magnets are cooled with liquid helium at 4.2 K and the liquid bath can be pressurized up to 2 bars to regulate the temperature of the magnet during operating conditions. In this facility, it is possible to measure and dissociate the heat loads coming from the magnet and the current leads by flow-metry. The voltage of the solenoids and their current leads are measured using National Instrument devices and monitored with a Labview program to identify and analyze eventual quenchs. The magnetic performance of the magnets are also monitored dynamically with 3D hall probes. Numerous cryogenic temperature sensors are used to characterize the thermal evolution of the magnet and its current leads during the test. In the present paper, the compact facility is described and the first results obtained on the current leads of the magnet prototype are presented.
A Leak Detection System for Valves Cooled to 20 K while Cooled with a GM Cryocooler
Authors: Lyu B K , Xu D , Nishimura A , Jia P , Huang R J , Huang C J , Shen F Z , Li X , Wang Y G , Sun W T , Li L F
Published: June 2020

Cryogenic valves are widely used in cryogenic systems such as aerospace propulsion systems and various cryostats. Under cryogenic temperatures, thermal shrinkage and sealing material hardening may dramatically enlarge the sealing gap of the valves, which leads to a serious leakage. Therefore, a detection system for cryogenic valves is badly needed. In this paper, a cryogenic leak detection system is established, which has the capability of detecting internal and external leakage of the valves at temperatures around 20 K. Compared with the traditional cryogenic leak detection system, this system, getting rid of threats from cryogenic liquid, successfully enhances the overall safety and is able to test five valves simultaneously to improve efficiency. This system optimizes the heat exchanger structure and shortens the cooling time.
Testing of SHIIVER MLI Coupons for Heat Load Predictions
Authors: Johnson W L , Oberg D , Frank D , Mistry V , Koci F D
Published: June 2020

The Structural Heat Intercept, Insulation, and Vibration Evaluation Rig (SHIIVER) is designed to demonstrate the performance benefits of installing multilayer insulation (MLI) and structural vapor cooling onto a large hydrogen tank as a part of an upper stage. The intent of the 4 meter sub-scale demonstration is to design the MLI in a manner that its performance can be scaled to a full sized application. In order to predict the performance of the blankets as well as aid in the design, several features needed to be tested. Four different coupons were tested and evaluated for thermal performance relating to the number of layers, the seams, and the attachment mechanisms. The attachment mechanisms were further tested for structural strength at nominal application temperatures. From the testing, the number of layers were determined to be 30, and heat load penalties were determined for the seams and attachments. The attachment mechanisms passed all load testing with a margin of greater than 40%.
Measurement of heat flux in multi-layer insulated helium cryostats after loss of insulating vacuum
Authors: Weber C , Henriques A , Schirle S , Grohmann S
Published: June 2020

The dimensioning of pressure relief devices (PRD) for cryogenic pressure equipment requires knowledge on the heat input at the maximum credible incident. In helium cryostats, this situation is typically defined by the loss of insulating vacuum (LIV), where the heat load is induced by desublimation and condensation of atmospheric air on the cryogenic surface. This surface is often covered with multi-layer insulation (MLI) in order to reduce the thermal radiation heat load in standard operation. During loss of insulating vacuum, the MLI represents a diffusive barrier for the air to reach the cryogenic surface, reducing the heat flux as well. Experimental reference data for the heat flux in case of LIV exist mainly for blank surfaces; only few data are published for MLI-covered helium surfaces. Therefore, the effect has been investigated in the cryogenic safety test facility PICARD at KIT. This paper presents the results of venting experiments carried out with different numbers of layers and different types of MLI.
The low temperature mechanical properties of a Nitronic 40 forging
Authors: Walsh R P , Radcliff K J , Lu J , Han K
Published: June 2020

Nitronic 40 forged shells are typically used for structural reinforcement in high field pulse magnet design and applications. To better understand the mechanical performance of this versatile high strength austenitic steel a series of mechanical tests were conducted. Tensile were performed at 295 K, 77 K and 4 K, and cryogenic fracture mechanics tests were performed at 77 K and 4 K. The effect of temperature on strength, ductility, toughness and fatigue crack growth rate are evaluated. Microstructure and composition effects are also presented and discussed.
DC surface flashover characteristics of ZnO/Epoxy composites at room temperature and 77 K
Authors: Zhang Kaikai , Huang Chuanjun , Wang Yongguang , Zhang Hua , Zhang Chi , Wu Zhixiong , Liu Huiming , Xu Dong , Huang Rongjin , Li Laifeng
Published: June 2020

Epoxy (EP) resin based nano-composites are widely used in high voltage direct current (HVDC) high temperature superconducting (HTS) power cable. In this paper, the DC surface flashover characteristics of ZnO/EP composites were studied at both room temperature and 77 K. The samples were made by dispersing ZnO nano-particles into EP resin with various weight percentages of 0%, 1%, 3%, 6% and 10%, respectively. The experiments were carried out with a cryogenic system in which DC high voltages ranging from 0 kV to 100 kV were supplied. The results showed that the surface flashover voltages increased with the increase of ZnO content at both room temperature and 77 K, and the surface flashover voltages at 77 K were higher than that at room temperature for composites with the same ZnO content.
Effect of Non-Uniformity of Electric Field on Breakdown Strength of Cryogenic Gaseous Insulation Media for Superconducting Power Applications
Authors: Telikapalli S. , Kvitkovicova M. , Cheetham P. , Park C. , Kim C.H. , Graber L. , Pamidi S.
Published: June 2020

A new experimental set up for measuring the breakdown strength of gas media in weakly non-uniform electric field at cryogenic temperatures and high pressures is described. Measure of breakdown strength of helium gas at 77 K and 293 K in a non-uniform electric field with a field efficiency factor 62.5% are presented. The results suggest that the breakdown strength in weakly non-uniform electric field relate to that of uniform electric field by the field efficiency factor, η. This relationship holds good for both 293 K and 77 K data. This observation expands our previously reported systematics of dielectric strength in uniform electric field to the weakly non-uniform electric field conditions, which is important for designing HTS power applications. The established relationship eliminates the need for costly experiments for measuring the dielectric strength at a specific operating temperature and pressure and in the required non-uniformity of the electric field.
Thermal and Electrical Properties of Isocyanate Derived Organic Aerogels for Cryogenic Insulation Applications
Authors: Churu G , Demko J A , Mole A , Duckworth R C , Lu H , Malakooti S , Leventis N
Published: June 2020

The use and storage of cryogens such as liquefied nitrogen, helium, hydrogen among others requires reliable and efficient thermal insulation systems. Passive insulation from high performance materials that are well-known for their inherent low thermal conductivity would reduce the overall costs involved in design, manufacture and maintenance of such systems. One such class of materials are referred to as aerogels. These materials are known for their low density, high mesoporosity, high surface areas, low thermal conductivity and high acoustic impedance. Aerogels were invented by S.S. Kistler in 1931 and the most common type are those made of silica. However, the inherent fragility of silica aerogels makes them hard to mass produce, and therefore applications have been limited. A major breakthrough was introduced by our team almost 20 years ago with the invention of polymer crosslinked silica aerogels. Those materials shifted attention to all-polymer aerogels that have overcome all fragility issues associated with their inorganic counterparts. This study focuses on such polymeric aerogels that can be mass produced as large monoliths while maintaining the low thermal conductivity of traditional silica aerogels over a wide temperature range. Manufacturing flexibility of polymeric aerogels allows fabrication of blocks and sheets that can be applied in various configurations to insulate cryogenic and superconducting devices. The thermal conductivity with 80 K and room temperature boundary are reported as well as other properties (electrical), that need to be considered when designing devices for cryogenic applications.
Macroflash boiloff calorimetry instrument for the measurement of heat transmission through materials
Authors: Fesmire J E , Bateman C D , Thomas J L
Published: June 2020

The Macroflash is a flat plate boiloff calorimeter that provides effective thermal conductivity (ke) data for a wide range of materials from thermal insulation to structural composites to ceramics. The apparatus and method provide a practical, standardized way to measure heat transmission through materials under steady-state conditions at below-ambient temperatures and under different compressive loads. Another unique feature of this device is that it can provide test data at both large and small temperature differences. Using liquid nitrogen as a method to directly measure the heat flow rate, the device is applicable to testing under an ambient pressure environment at a wide range of temperatures, from 77 K to 403 K. Test specimens may be isotropic or non-isotropic; homogeneous or non-homogeneous. The Macroflash is currently calibrated in the range from approximately 10 mW/m-K to 1,000 mW/m-K using well-characterized materials. Reference data for hundreds of test specimens including foams, powders, aerogels, plastics, composites, carbon composites, wood, glass, ceramic, metal, and multi-layered composites have been compiled from Macroflash testing. The Macroflash apparatus is described and its operation, instrumentation, and control system discussed. The calibration approach is detailed as well as analysis of key data sets of standard materials.
Understanding Surface Flashover in Helium Gas Cooled High Temperature Superconducting Devices
Authors: Al-Taie A , Cheetham P , Kim C H , Park C , Graber L , Pamidi S V
Published: June 2020

Surface flashover voltage on solid insulators in gas cooled superconducting power devices is studied. The relationship between the surface flashover voltage and the dielectric strength of the gas media is established. Analysis of the data on surface flashover voltage measurements on cylindrical samples made of high-pressure fiberglass laminate (G10) in three different gas media with varying dielectric strength and pressure showed a positive correlation between the surface flashover voltage and the dielectric strength of the gas both at room temperature and 77 K. The positive relationship, however, is not linear. The results suggest that using gas media with higher dielectric strength, employing higher pressure, and lowering temperature in HTS power devices leads to higher surface flashover voltages and higher operating voltages because surface flashover is usually the limiting voltage in devices that use solid support structures and possess voltage gradients.
High throughput and variable temperature superconductor integrated circuit test and evaluation using ICE-T
Authors: Sahu A , Chonigman B , Talalaevskii A , Dotsenko V , Ruotolo S , Tang J , Gupta D
Published: June 2020

Superconductor digital integrated circuits (ICs) require rapid evaluation of multiple copies to obtain statistical operational data. These data are used for assessing model-to-hardware correlation and facilitate iterative IC design development. The Integrated Cryogenic Electronics Testbed (ICE-T) is a cryogen-free test platform, which can test multiple chips simultaneously with similar convenience to a liquid-helium immersion probe and with cooldown times of between 3.3 to 4.5 hours. We have developed a three-chip insert to increase the volume of chip testing and demonstrated simultaneous cooling of six chips with two such inserts. We report the test statistics collected from 27 chips across a single wafer. We have also used the ICE-T’s convenient temperature control system to evaluate chips in the 3.5 - 6 K range. Such evaluation determines the robustness of circuit design and its tolerance to critical current fluctuations due to fabrication variation.
A study on the extent of Ag protrusions in different TiO2-coated Bi-2212 wires
Authors: Hossain S I , Jiang J , Trociewitz U P , Lu J , Bosque E , Kim Y , Larbalestier D C , Hellstrom E
Published: June 2020

We report on the extent of Ag protrusions into the TiO2 insulation layer on 9 different Bi-2212 wires after overpressure heat treatment. These wires were made with different powders and had different diameters and geometries, including aspected and twisted wires. To replicate coil heat treatments, we also studied whether increased time spent in the melt state affects the protrusions. We found that Ag protrusions are not universal and increasing the time in the melt state does not affect the protrusions.
The effect of APC/YBCO interface on the angular range of effective pinning by one-dimensional artificial pinning centers in YBa2Cu3O7-xnanocomposite films
Authors: Ogunjimi V , Gautam B , Sebastian M.A. , Haugan T , Wu J
Published: June 2020

The APC/YBCO interface has been reported to directly affect the pinning efficiency of 1D APCs atB//c-axis. This raises a question on how the APC/YBCO interface affects angular range of the pinning effectiveness for a given 1D APC. In this work, two types of 1D APCs of different APC/YBCO interfaces and hence pinning efficiencies were selected to understand the correlation of the pinning efficiency atB//c-axis and the angular range of the effectiveness. Specifically, BaZrO3(BZO) and BaHfO3(BHO) 1D APCs were selected for a comparative study in the APC/YBCO nanocomposite films. The BZO and BHO 1D APCs have comparable diameters in the range of 5-6 nm. In the doping range of 2-6 vol.%, both BZO and BHO formc-axis aligned 1D APCs in YBCO films. However, differences are present at their interfaces with YBCO. While the BZO/YBCO interface is semi-coherent, a coherent BHO/YBCO interface has been found to be critical to the higher pinning efficiency of the BHO 1D APCs. Therefore, they provide ideal systems for investigation of the angular range of pinning effectiveness by 1D APCs. By evaluating the nanocomposites’ maximum pinning force density (Fp, max) and its locationBmax, normalized to that of the reference YBCO film as functions of magnetic field (B) orientation at temperatures of 65–77 K, a quantitative correlation between the pinning efficiency of the BZO 1D-APCs and their effective angular range was obtained. Our results indicate that all 1D APCs can provide enhancedBmaxover certain angular ranges away from thec-axis. However, 1D APCs with higher pinning efficiency, such as BHO 1D APCs can have enhancedFp, maxover the entire angular range ofB-orientations at temperatures of 65-77 K with respect to that for the reference YBCO sample.
Homopolar superconducting AC machines, with HTS dynamo driven field coils, for aerospace applications
Authors: Kalsi S , Badcock R A , Hamilton K , Storey J G
Published: June 2020

There is worldwide interest in high-speed motors and generators with characteristics of compactness, light weight and high efficiency for aerospace applications. Several options are under consideration. However, machines employing high temperature superconductors (HTS) look promising for enabling machines with the desired characteristics. Machines employing excitation field windings on the rotor are constrained by the stress limit of rotor teeth and mechanisms for holding the winding at very high speed. Homopolar AC synchronous machines characteristically employ both the DC field excitation winding and AC armature windings in the stator. The rotor is merely a magnetic iron forging with salient pole lumps, which could be rotated at very high speeds up to the stress limit of the rotor materials. Rotational speeds of 50,000 RPM and higher are achievable. The high rotational speed enables more compact lightweight machines.

This paper describes a 2 MW 25,000 RPM concept designs for machines employing HTS field excitation windings. The AC armature winding is made of actively cooled copper Litz conductor. The field winding consists of a small turn-count HTS coil that could be ramped up or down with a contactless HTS dynamo. This eliminates current leads spanning room-temperature and cryogenic regions and are major source for thermal conduction into the cryogenic region and thereby increase thermal load to be removed with refrigerators. For early adaption of this technology for the aerospace applications, this 2 MW machine weighing 380 kg with an efficiency > 99% represents an attractive option.
2-layer Cable-in-Conduit for Hybrid-Coil Magnets
Authors: Breitschopf J , Chavez D , Elliott T. , Kellams J , McIntyre P , Sattarov A
Published: June 2020

Recent results are reported in the development of 2-layer cable-in-conduit (SuperCIC) that is designed for use in hybrid-coil magnets. SuperCIC preserves the full performance of the individual wires, and can be formed into flared-end windings for dipoles into layer-wound toroids and solenoids for hybrid windings for tokamaks. The structure of the SuperCIC windings is designed to accommodate winding and heat-treating sub-windings of Bi-2212, Nb3Sn, and NbTi separately and then assembling them and preloading in the magnet.
Development of HTS Current Leads for the ITER Project
Authors: Bauer P , Ballarino A , Devred A , Ding K , Dong Y , Niu E , Du Q , Gung C Y , Han Q , Heller R , Huang X , Ichihara T , Lee S , Li J , Liu C , Liu Cl , Lu K , Mitchell N , Song Y , Spina T , Ran Q , Taylor T , Yamada S , Yang Y , Zhou T
Published: June 2020

The HTS current leads for the ITER project will be the largest ever operated, with unprecedented currents, up to 68 kA and voltages, up to 14 kV. According to the ITER agreement they will be provided in-kind by China. After an extensive development program at the Hefei Institute of Plasma Physics (ASIPP), the ITER current leads were designed and qualified. The following discusses the main highlights of this development, with particular emphasis on the description of the design of the different types of ITER current leads and their final qualification in dedicated cold tests in nominal conditions.
Evaluation of triangle´s triple restriction on conventional construction and modular construction-Example: New building of the University of the Coast
Authors: de la Puente Molina S E , Espitia Ticora J L , Capera Rodríguez O A , Palomeque Sánchez Z A
Published: June 2020

This document evaluates and compares the modular construction system against the conventional construction system, analyzing it from the triangle of the triple restriction of the PMBOK guide (5th edition), which corresponds to the analysis of the scope, time and cost that can be achieve in the execution, which is focused directly on a real building of higher education, as a case study was used the university corporation of the CUC coast located in the city of Barranquilla. The main purpose of the research is to demonstrate the strengths, advantages and disadvantages of each construction system and once the real results were obtained to be able to make the application in professional practice for the management of the works and the execution of higher education projects, in this way the new construction processes are potentialized as a contribution to the development of architecture and innovation in Colombia, which is a country that is seeking to enter new methodologies and construction systems which must be aligned with the management issues that are being applied in the construction guild.
Evaluation of the coughing power of the Opuntia ficus indica for removal of turbidity in waters of the Guatapuri River (Colombian Caribbean)
Authors: Vidal-Tovar C R , Moscote-Vides E M , Vides-Redondo A J , Severiche-Sierra C A
Published: June 2020

The purpose of this article is to publicize the evaluation of the effectiveness of Opuntia ficus indica as a coagulant during the treatment of raw water from the middle basin of the Guatapurí River, in the Department of Cesar, Colombia. Tuna coagulant is purely organic; it has been shown by phytochemical studies performed on Opuntia ficus indica the presence of some minerals among some others; contains glycides or carbohydrates. The evaluation was carried out using the jug test equipment, which operated by varying the revolutions per minute (20, 30 and 40), keeping the mixture fast at 125 rpm and settling for 30 minutes. The samples were physically characterized (Turbidity, Alkalinity, pH and total suspended solids) taking into account the methods specified for parameter in the Standard Methods. With samples of 345.9 NTU and 2799.1 NTU at optimal doses of 658.75 mg/L and 1976.3 mg/L respectively, removals up to 97% and 99.5% were observed in the same order. It was shown that the variation of the slow mixture only influenced with the sample of 2799.1 NTU, being the most effective treatment at 30 RPM.
Obtaining a sugar syrup from the use of the extract of the guácimo fruit (Guazuma ulmifolia lam)
Authors: Vidal-Tovar C R , Cadavid-Osorio C A , Angulo-Blanquicet G E , Severiche-Sierra C A
Published: June 2020

The main objective of this work was to elaborate a sugary syrup from the use of Guácimo fruit extract (Guazuma Ulmifolia Lam) using the leaching method (solid - liquid), which can be used as a partial or total substitute for sugar. The experimental design that was applied for the extraction process was a factorial design 23; the data obtained were evaluated with the software Statgraphics. Once the extracts were obtained, physico-chemical tests were carried out and reductive sugars and dextrose equivalent were determined in each one. To obtain the syrup, the four extracts having the highest% ED were concentrated at constant temperature and time (50 ° C and 4 hours); The determination of the presence of reducing sugars was done using the techniques of colorimetric analysis (miller’s method) and chromatography (HPLC). The products that were obtained during the process were extreme conversion syrups with a range of dextrose equivalents of 90.13% - 98.27%. The syrup that obtained the highest percentage of equivalent dextrose (J3) was subjected to a sensory hedonic test, which consisted of 3 samples of sweetened coffee at different concentrations of sweet sugar syrup and sugar (sucrose), where M1 contained 80% sugar syrup of guácimo and 20% of table sugar. M2 contained 50% guácimo sugar syrup and 50% table sugar. M3 contained 100% sugar guacimo syrup and 0% table sugar. The results showed that the mixture that obtained the highest organoleptic acceptance was M2, followed by M3, which states that the syrup can substitute partially the common sugar. The above data allow the guácimo fruit to be taken into account as an alternative raw material for the production of sugar syrups and other products aimed at human consumption.
Scientific reasoning skills and patterns of use of Information and Communication Technologies. The case of the students of the Universidad de Santander (Valledupar, Colombia)
Authors: Angulo Blanquicett G E , Angulo Blanquicett G E , Vidal-Tovar C R , Rios-Dominguez I C
Published: June 2020

This research establishes the relationship that has had the development of the skills of scientific reasoning and the patterns of use of tools and resources of information and communication technology (ICT). For that, it is necessary to use Lawson Test and to have into account ICT National Standards for students that USA International Society for Technology in Education (ISTE) suggest. Also, this paper is tackled from a non-experimental design featuring a correlational – transectional range. The population consists of 2035 students from a higher education institution of the Colombian Caribbean coast. Besides, stratified random sampling is used defining, defining strata and a representative sample for academic programs. Personal survey was used to collect information. The existence of relationship between scientific reasoning skills and patterns of use of information and communication technology was confirmed.
Traffic flow prediction model and probability of congestion
Authors: Pilamunga Poveda M , Lavin J M , Aldás Sánchez M , Ríos Insua D
Published: June 2020

Investment in the management of integrated activities for better community development determines the progress of a city. Generate actions directed to change and evolution can promote greater satisfaction among its inhabitants. One of those activities is the one concerning transit, which is one of the most transcendental factors in the quality of life of a modern city. Thus, good road planning is of vital importance for their development. To do this, studies must be conducted that allow us to have a diagnosis of reality and thus make decisions would help to minimize or avoid problems that are occurring or that may appear in the future. However, to make a study of this type whenever it is required is expensive in terms of time and resources. This work proposes a model that allows predictions of traffic flows in different relevant sections of a city and, predict issues such as traffic saturation in them, thus determining possible solutions to road congestion, it can be presented at a given moment. These possible alternative solutions could consequently would reduce costs in time, fuel, pollution among others.
Identification of critical variables in conventional transformers in distribution networks
Authors: Marriaga-Márquez I.A. , Gómez-Sandoval K.Y. , Grimaldo-Guerrero J.W. , Nuñez-Álvarez JR
Published: June 2020

Transformers are essential equipment to the operation of electrical power systems, a failure causes the lack of electricity supply to end-users, affecting the operating indicators of companies in the distribution sector. The investigation presents an identification of the faults in transformers through a fishbone diagram, an evaluation of the variables that cause the identified failure using the cross-impact matrix method and a proposal to improve the performance. The results will enable a plan to be developed for taking action with monitoring plans to avoid faults that could put the electrical asset at risk and achieve a better performance of the distribution network.
Drivers of Biomass Power Generation Technologies: Adoption in Colombia
Authors: Reyes-Calle W , Grimaldo-Guerrero J.W.
Published: June 2020

The share of non-conventional renewable energies in Colombia represents less than 4% of electricity generation; the government aims to increase the net installed electricity generation capacity to over 10% by 2028. A structural analysis was carried out for decision-making: international experiences was used to identify Social, Environmental, Technical and Economic indicators and with the MICMAC method, the key variables were identified to define improvement strategies. This research determined the driver elements that will allow Colombia to effectively include biomass as an electrical energy source.
Degradation of Cyanide from Gold Mining Wastewater Using Photocatalysis
Authors: Mestre-Martinez R M , Marrugo-Pautt I , Correa-Turizo R R , Severiche Sierra C A , Baldiris-Navarro I
Published: June 2020

In recent years, water quality issues related with hazardous wastewater and toxic substances have attracted worldwide attention. Cyanide is a major toxin in wastewater resulting from a diversity of industries, including gold mining. Cyanide has adverse health effects on people as well as other living organisms. The toxic effects of cyanide are so important to cause nerve damage and thyroid glands malfunctioning. In this paper, the degradation of cyanide in waters resulting from gold mining activity was carried out in a batch system with two catalysts TiO2 Degussa P-25 and TiO2 doped with copper heteropolyimolybdate, that was synthesized in laboratory and characterized by FTIR and XRD. Assays showed a degradation of 98.55% with a concentration of 0.3 g/L of TiO2 and 97.17% with TiO2 doped with 1% of Cu heteropolyimolybdate (1 g/L) in 50 min of reaction. A real mining sample showed a cyanide degradation of 55.76% with TiO2 in 240 min of reaction. All the assays were made applying photodegradation using a 125-Watt mercury lamp as source. These results are encouraging to use this technology for the removal of cyanide coming from highly contaminated aqueous effluents.
Design of a Fuzzy Controller for a Hybrid Generation System
Authors: Nuñez J. R. , Mestre J. , Cabello J. J. , Dominguez H. , Fong J. , Peña L. , Benítez I. , De Oliveira D.
Published: June 2020

This paper presents the design of a control system for the automatic connection/disconnection and distribution of load, between an asynchronous alternator and a generator, in a hydroelectric central that works in isolated mode. The design of a control algorithm based on fuzzy logic is exposed, as this is a flexible method to be used in different installations with a variety of technology. The controller is supported on the Arduino Mega 2560 platform, in order to develop a low-cost system with its own technology, it is tested by computer simulation using the professional software Proteus v7.7, which guarantees that once validated the correct operation of the controller can be migrated to another system, say for example a PLC. The results obtained are shown and the simulations performed to the different blocks of the system are explained.
A proposal for updating the Response Spectrum of San Jose de Cucuta, Colombia
Authors: Florez C. H. , Marquez J F , Lozano C F
Published: June 2020

An analysis of seismic signals captured in three stations of the network of accelerographs of the Colombian Geological Service (SGC, by its acronym in Spanish) was developed for the city of San Jose de Cucuta, Colombia. Earthquake Equivalent, Response Analysis (EERA) and DEGTRA4 software were used for analysis, processing and calculation of signal response spectra during the characterization and propagation modelling of the signal by profiles. For the accelerograms family, a normalization factor computed with respect to the Peak Ground Acceleration (PGA) was obtained by superposition against the typical design spectrum of the Colombian earthquake resistant code (NSR10). It was found that there is a band of frequencies above the maximum acceleration zone of the design spectrum of the current standard. This suggests a revision of the seismic threat of the city of Cucuta and the urgent need to develop the seismic microzoning, which would allow a substantial reduction of the seismic risk.
Growth Optimization of Chlorella Vulgaris in Mixotrophic Culture Enriched with Nutrients using Experimental Design
Authors: Baldiris-Navarro Ildefonso , Aponte Jorge Sanchez
Published: June 2020

In this research, statistical optimization designs were applied to evaluate the growth of the Chlorella vulgaris in mixotrophic cultures enriched with nitrogen and phosphorus. The influence of each factor was evaluated at three levels, so a multifactorial experimental design was created 32. The results obtained showed that microalgae growth improves 32% by adding 50 mg of nitrogen and 25 mg of Nitrogen to the culture. This project demonstrates the relevance of the design of experiments for the optimization of algal biomass production in order to obtain bioproducts.
Benefits of the instrumentation, monitoring and control systems (IMC) of bridges in Colombia, from an economic point of view through a case study
Authors: Castro J D , Suarez L , Cerón I C
Published: June 2020

An instrumentation, monitoring and control (IMC) system is the result of the application of different branches of engineering such electrical, systems and telecommunications, applied to solve a problem in civil engineering, and achieving a radical innovation in the construction and the maintenance of bridges. These different branches come together to carry out activities such as the development of measurement instruments, applications for the storage and analysis of data, and the transmission thereof. This article presents the state of art about road infrastructure controls in Colombia, particularly on bridges. It summarizes some important cases of collapse with their main causes, establishing as an effective solution IMC of the bridges throughout the structures’ life cycle, showing the benefits associated with the initiation of the system. In addition, an economic analysis of the installation of an IMC system is presented through a case study of one bridge located in Colombia, which has enabled us to identify and find relevant information related to those responsible for the project, the required instrumentation and the investment percentages regarding this particular type of project. The text consists of seven sections, which address the problems, instrumentation, software and personnel requirements for this type of project in Colombia, and finally to examine the associated costs.
Agriculture 4.0 the advance in models and new knowledge to improve production
Authors: González-Salazar F
Published: June 2020

This article presents Research on the design and application of a model that allows controlling agroecological variables and conditions based on inductive-deductive methods supported by qualitative and quantitative tools such as metadata, trend tools and comparison graphs. This Model represents the knowledge of the farmer in a different kind of applications that allows the continued progress of the agriculture. The model has been tested with some agricultural, plant and animal species in controlled in real environments, where the quality of the cultivated species can be measured to determine improvements in nutritional quality, this measure is made by sensors of temperature, pH, lumens and humidity then we have a mathematical model that allows the simulation of the variables that we want to control that includes monitoring and control times. From here, concepts of agriculture 4.0 are associated, which consists in mitigating the risk in different in the environments. Currently, the integration of concepts and technologies associated with the fourth industrial revolution is evaluated through the simulation of variables and comparison between ideal and real models.
Study of linear strain gauges at micron scale for the reduction of external factors
Authors: Villamizar C T , Arevalo W Y , Castiblanco C C
Published: June 2020

In the present article, the design and simulation of a strain gauge is shown, which serves to measure deformation or pressure in different applications of the industry. In this way, the respective simulation was carried out in the COMSOL Multiphysics 5.2 software, where the 3 linear meander gauge was subjected to external factors such as temperature and pressure, with this, the different results obtained were shown the mechanical behavior and of Graphene and Silver grid materials and substrate Paper. On the other hand, in front of the design of the three-way linear strain gauge, M.E.M.S (Micro-electromechanical Systems) parameters technology was used to reduce its dimensions in micrometers to reduce the effects of the respective external factors where these produce errors in the measurements.
Automation of the Conductive Ink Synthesis from Recycled Parts from Metallurgical and Chemical Residues Joined to Polymer Resin and Solvent
Authors: Lara Jhon , Cantillo Sergio , Castillo Karolina , Montalvo Jorge , Lara Karen
Published: June 2020

Conductive ink is a modern method for making printed circuit boards (PCB’s), with new and somewhat different properties such as electrical conductivity, adhesion on non-conventional surfaces (glass, wood and paper) and the printability it possesses. However, such technology is cost and limited access given the machinery needed for the synthesis of ink and the tax on our currency. This situation leads to an increase in the technological gap between developed and developing countries. Therefore, the objective and motivation of this work is to present InkCo, a machine that automates the process of synthesis of conductive ink from metallurgical and chemical waste of the region. Understanding that through automation, virtual CAD modeling and materials science it is possible to develop the objectives of sustainable development (ODS) 4, 9 and 12, which seek innovation in industry and responsible consumption. Based on these ideas, InkCo is a mechatronic technology product that seeks to reduce this technological gap, through the implementation of rapid prototyping technologies (3D printing, laser cutting and prototyping of controlled circuits), for its structural construction, and thus generate an input (conductive ink) that can be used for the creation of more unconventional technology (3D printing of amorphous circuits on dielectric surfaces).
Smart Institution Model
Authors: Pilamunga Poveda M , Santamaría Aguirre J L , Viera Alulema E
Published: June 2020

An institutional management model focused on the optimization of processes and services that emulates a Smart City on a smaller scale is the proposal that the Technical University of Ambato must direct its development towards a vision of efficient connectivity, reduction of resources and the approach to a Green workflow. The current problem of bureaucracy existing in public institutions in developing countries is a factor that leads to unsuccessful expenditure of time, money and personnel that must generate several steps within the value chain and due process to achieve a procedure that results in an action or service.. The model proposal focuses on the connectivity between teachers, students and the institution for the automation of activities that were performed manually, generating a virtual model that reduces time and processes; the use of security devices for the identification of people within the university environment and the communication carried out mainly through wearables with support of touch screens, mobile devices and apps; these tools will serve as a support for fast and fluid results under a solid data platform, that allows the collection of relevant information of diverse nature and its application to solve specific needs of the institutional and academic environment.
Information T echnology Governance Model, Based on Risk Management and Information Security for Colombian Public Universities: Case on Study University of La Guajira
Authors: Viecco L R , Arevalo J G
Published: June 2020

Nowadays Universities require the implementation of practices in (IT)information technology governance issues where it involves structures, processes, mechanisms and measurement indicators for the good performance of Information Technology. In order to make a strategic alignment that defines the generation of value, and that is why this research shows the design of an IT governance. Based on model risk management and information security for Colombian public universities, for which its strategic alignment, its strategy is analysed business. Its institutional educational project in order to consolidate a model adjusted to the particular needs of each academic faculty.
Analysis of the water quality risk index for human consumption in urban areas of the department of Bolivar
Authors: Polo-Carrillo Emilia , Morales-Simancas Geraldine , Cabarcas-Ariza Yudis , Valle Rodríguez Jorge
Published: June 2020

Objective: To analyze the results of the Water Quality Risk Index for Human Consumption in Urban Areas of the Department of Bolívar. Materials and methods: A descriptive investigation was developed, with the objective of evaluating the compliance of the physical, chemical and microbiological characteristics of water for human consumption. The direct observation technique was used whose results are based on the application of the standardized measuring instrument authorized by the Ministry of Social Protection in Colombia - IRCA for estimating compliance with acceptable parameters established in current regulations. Results: It was found that of the 46 municipalities in the department of Bolívar, study focus 18 presents water that is not suitable for human consumption that requires special surveillance and 3 municipalities have sanitary waters that require maximum, special and detailed surveillance. Conclusions: The need to establish alternatives by the competent entities that improve the quality of water for consumption in some municipalities of Bolívar and implement strategies for the prevention of waterborne diseases was evidenced.
Design and implementation of an intelligent thermal chamber to produce plantain hills
Authors: Hurtado J López , Gallego Becerra H A
Published: June 2020

The project is aimed on the design and construction of a prototype device which allows the measurement, visualization and control of the temperature and relative humidity, and soil moisture inside a thermal chamber. This prototype consist mainly of two sensors, one of them to measure the temperature and humidity in the air, and the other one to measure the humidity of the soil; In addition, an Arduino development card, which be used to process the data and control the different measured Physical variables. A liquid crystal display (LCD) to display the measured data and the process it takes; In addition to other electronic devices that complement the processing and control in real time, the backup or monitoring of the thermal chamber through the days, the automatic turning on and off of a misting irrigation system and the automatic opening or closing of two windows used to let circulate oxygen inside the place.