bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tailoring the Thermal Conductivity of Paraffin and Low-cost Device for Measuring thermal conductivity of Phase Change Material
Authors: Bhandwal Mohit , Verma Amritanshu , Singh Sikarwar Basant 
Published: November 2019

Abstract
In this work, experiment is carried out for melting process of paraffin wax dispersed with high conductive nano-fillers such as Carbon Nanotube (CNT) and ZnO. In addition, a simple, economically viable, easy operating experimental setup is proposed to measure the thermal conductivity of altered PCMs. In this setup, the sample is placed in an insulated transparent cavity and its one end maintained at constant temperature. However, other ends are adiabatic. Temperature at four specific location of melting paraffin in the cavity are measured by T-type thermocouples. The digital camera is used to capture the instantaneous images of the moving thermal front of melting at various time steps. ImageJ® is used to know velocity of the melting front of PCMs from captured images. Based on energy balance, a mathematical expression for estimating the conductivity of the altered PCMs is derived. The measurement of proposed device is compared with commercial thermal conductivity measuring device and data available in the literature. The obtained results have 95% confidence level against the commercial device results and literature results. Post-calibration, experimental study of pure paraffin and altered paraffin wax are carried to know insights of Spatio-temporal energy storing in form of latent heat. This research is useful for design the heat sink for thermal energy management of pulsating heating generating device.
Numerical modeling of interface diffusion during heating of spherical metal heterostructure
Authors: Golovneva E I , Golovnev I F , Igoshkin A M 
Published: November 2019

Abstract
This work is a pilot one and addresses to the development of a physical and mathematical model of alloy formation; this model permits conducting a micro-level detailed study of the influence imposed by the ratio of the thermophysical parameters of the matrix and nanoclusters materials, as well as external controlled parameters on the physical properties of the alloys. The article presents the developed methodological approaches for the numerical simulation of alloys formation with the help of molecular dynamics method (MDM).
Numerical analysis of the water steam jet gasdynamic parameters influence on the hydrocarbon fuel combustion in a pilot burner
Authors: Krasinsky D V , Sharypov O V 
Published: November 2019

Abstract
On the basis of the conserved scalar approach with constrained-equilibrium chemistry model, variant numerical simulation of aerodynamics, heat transfer and the vaporized diesel fuel combustion processes, including soot formation and its effect on radiative heat transfer, has been performed in the pilot burner designed according to a concept of a hydrocarbon fuel combustion enhancement by axial injection of superheated water steam high-speed jet. The aerothermochemical structure of multicomponent reacting flow inside the burner has been analysed for the three cases of numerical study, including two regimes of the water steam axial injection with different jet velocity, and one regime of air injection through the same axial nozzle. The dependencies of the burner flame characteristics and its ecological performance on the given gasdynamic parameters of the discharged steam or air jet have been obtained. Also the numerical study has confirmed the low-NOx features of the burner operational regimes with water steam injection.
PIV measurement of shock wave / laminar boundary layer interaction
Authors: Vishnyakov O I , Polivanov P A , Budovsky A D , Sidorenko A A 
Published: November 2019

Abstract
The paper deals with study the area of interaction incident shock wave with a laminar boundary layer by PIV technique. The several data processing techniques to determine PIV measurements usability in transonic flow with small typical scales are compared in the paper. The results show that the major limitation of the PIV technique are associated with the seeding particles inertia.
Fundamental issues related to flow boiling and condensation in microchannels – experimental challenges and opportunities
Authors: Kuznetsov V V , Shamirzaev A S 
Published: November 2019

Abstract
In recent years, application of the microchannels has received considerable attention due to their capability for thermal management of microelectronic equipment, high power devices and development of compact evaporators. The present paper focuses at a discussion of the heat transfer during flow boiling and condensation in microchannels of the heat sink to identify the methods to improve heat transfer performance and select the physically based models for heat transfer prediction. The main purpose of this study is to discuss the mechanisms of heat transfer in microchannels at different aspect ratio for the three-sided heating case using the experimental data were obtained for refrigerant R134a and dielectric fluid.
Direct numerical simulation of turbulent flow and heat transfer in a hexagonal rod bundle
Authors: Sergeenko K M , Yu Chulyunin A , Krasnopolsky B I 
Published: November 2019

Abstract
The aspects of numerical simulation of heat transfer in a flow along the hexagonal rod bundle are discussed in the present work. The direct numerical simulation is used to investigate the flow with Reynolds and Prandtl numbers varying in the range from 2500 to 10000 and 0.0043 to 7 correspondingly. The obtained simulation results demonstrate good agreement with available experimental data and semi-empirical correlations for the thermo-hydraulic characteristics of the channel. The empirical correlations for the Nusselt number distributions summarizing the results of the numerical simulations are proposed. The preliminary calculations have shown that the modelled time averaging interval is comparable with the initial transition time interval. This observation allows applying the approach, proposed in [7], to speed up the simulations.
Study of total heat losses in experiments with shear-driving liquid films in a mini-channel with intense heating
Authors: Zaitsev D V , Tkachenko E M 
Published: November 2019

Abstract
Recent works by the authors have shown the high efficiency of using thin liquid films, moving under the action of gas in a flat mini-channel, for removing high heat fluxes. In the present work, we carefully study the total heat losses in such a system. Total heat losses are divided into two portions: heat losses from the heating coil to the atmosphere and heat spreadings from the heater to the substrate. The relative values of the total heat losses prior to the crisis are decreasing with increasing critical heat flux and do not exceed approximately 20% for the critical heat flux between 500 and 900 W/cm2.
Hydraulic resistance and heat transfer augmentation in pipes with inner helical micro-ribs: Review, data generalisation, and technical recommendations
Authors: Popov I. A. , Skrypnik A. N. , Schelchkov A. V. 
Published: November 2019

Abstract
The paper presents the data generalization and development of general correlations for heat transfer and pressure drop in pipes with inner helical micro-ribs. Heat transfer and friction coefficient data were gathered from related investigations on single-phase turbulent flow of Newtonian fluid in pipes with various shape inner helically-ribbed surfaces
Semi-automatic detection of hepatic tumor in computed tomography images
Authors: Sáenz F , Vera M , López J , Huérfano Y , Valbuena O , Vera M I , Gelvez-Almeida E , Salazar-Torres J 
Published: November 2019

Abstract
In this work, the main purpose is develop a computational segmentation strategy for liver tumor semiautomatic detection. This strategy considers three-dimensional computed tomography images and it consists of techniques application that, on the one hand, diminish the noise and detect the edges of the objects present in those images and, on the other hand, generate the liver tumor morphology. For this, the sequence of techniques composed of gaussian smoothing, gradient magnitude, median filter, region growing and binary morphological dilation are used. The value obtained, for the metric called Dice score, show a good correlation between manual segmentation, performed by a hepatologist, and the tumor segmentation obtained using the proposed technique. This type of segmentation is the extreme utility for the characterization of hepatic tumors and the planning of the clinical behavior to be followed in the treatment of this human liver disease.
A two patch model for the population dynamics of mosquito-borne diseases
Authors: Gómez-Hernández E A , Ibargüen-Mondragón E 
Published: November 2019

Abstract
In this work, a model on the interaction dynamics of mosquitoes causing vector-borne diseases is formulated, without consider the human population as dynamic variables and including mobility from eulerian approach, in which the populations are not assigned to a place in particular, but they move between patches at certain rates. The results suggest that in order to eradicate the disease, the mosquito population in each patch must be controlled, but in order to reduce the magnitude of an epidemic outbreak, the transformation rate from susceptible to infected, the migration and immigration rate must be controlled.
Estimation of informal transport motorcycle emissions in the city of Ocaña, Colombia, as research training strategy for environmental engineering students
Authors: Fonseca Herreño L C , Valdes Solano D M , Alba Maldonado J M 
Published: November 2019

AbstractMototaxism in Colombia is considered an informal employment, in which a motorcycle is used to provide public service; it is a door-to-door service, without established routes, at a perennial frequency and low fares. This modality of employment began in the city of Ocaña about a decade ago, now it has popularized due to population growth, regional migration crisis and high unemployment rates. The “Universidad Francisco de Paula Santander” and the “Universidad Manuela Beltran” in Ocaña, Colombia; from their missional framework, aim to incentivize research training, raising the need to build training projects for students of second and third semester of environmental engineering, integrating statistics as a tool for decision making and data analyses, bringing the academy closer to contextual problems that the students can understand as their own. Environmental engineering students were able to participate with presentation of their results in different events, incentivizing their interest towards research and the use of statistics and mathematics as an important tool for data management and interpretation.
Parameter estimation, sensitivity and control strategies analysis in the spread of influenza in Mexico
Authors: Prieto K , Ibarguen-Mondragon E 
Published: November 2019

Abstract
In this paper we address a parameter estimation, sensitivity and control strategies analyses for influenza disease using a model the flows of people between four states: susceptible, exposed, infectious, recovered. We solved a curve-fitting mathematical model to Mexican influenza data using a nonlinear least-square method and the Landweber iteration. An optimal control problem is formulated and analyzed based on models between four states: susceptible, exposed, infectious, recovered; model considering educational campaign, vaccination and medical treatment as strategies for disease control. The sensitivity analysis is performed to determine which model parameters are the most important to disease transmission and prevalence. The numeric results suggest that an adequate implementation of these strategies during the outbreak of an epidemic could significantly mitigate the propagation of the disease.
Strengthening mathematical interpretation competence through the portfolio as a learning tool
Authors: Niño Villan M L , Gallardo Pérez H J , Villamizar Jaimes D 
Published: November 2019

Abstract
The purpose of the research is to strengthen the competence of mathematical interpretation through the portfolio as a learning tool in an educational institution of the “Municipio de Gramalote, Norte de Santander, Colombia”. The research is carried out from the socio-critical approach, qualitative paradigm and the chosen method is action research. The information gathering process was developed using the techniques of: participant observation and focus group. The key informants were two high school mathematics teachers and eighth grade students. The results show that in the diagnosis the participants’ lack of knowledge regarding the process of mathematical interpretation was evidenced; elements of knowledge are identified from the previous knowledge of the students and the preparation of the researcher teacher in the didactic sequence. The use of a tool such as the portfolio made it possible to motivate the learning process and to evidence in an orderly manner the abilities and capacities empowered by the students; there was an appropriation of learning around the analysis and interpretation of mathematics from concrete situations in the daily lives of the students, taking up their previous knowledge and using didactic elements and resources from their environment.
Human computer interaction in transport, a systematic literature review
Authors: Martinez-Toro G M , Ariza-Zabala G C , Rico Bautista D W , Romero-Riaño E 
Published: November 2019

Abstract
To enhance the performance of transportation systems a wide range of computer applications and computer software have been developed, which help users into the decision-making process. This paper intends to go into the field of human-computer interaction and transportation, by carrying out a literature review in order to recognize the usefulness of human-computer interaction and the way that it is used in the topic of transportation. human-computer interaction perspectives are applicable to describe, to analyze, to improve issues as user experience, user security, urban development, business model and so for. Understanding the way, a system is utilized is crucial to achieve the purpose of its design.
It governance model for state entities, as support for compliance with the information security and privacy component in the framework of the digital government policy
Authors: Ávila C , Chinchilla E J , Velásquez Pérez T 
Published: November 2019

Abstract
This article proposes an information technology governance model that facilitates the direction, control and fulfillment of the objectives of the implementation and maintenance of the information security and privacy program proposed by the Ministry of Information Technology and Government Communications Colombian to state organizations in the framework of the digital government policy. Based on the identification of the regulations of the Colombia state for the implementation of the information security and privacy model, the analysis of the existing information technology governance frameworks that converge on the governance and management objectives of the information security and privacy model is continued and finally the model is structured of governance. contributes to the technological development of the Colombia society through the construction of an innovative tool that facilitates the direction, control and rapid adoption of the management system of information security and privacy defined by the Colombia State, which results in the assurance and privacy of information of all Colombian that is in the hands of state entities, reducing frauds, the exposure of our personal information among other risks.
Fuel-air ratio required for combustion and analysis of gases in an intermittent kiln
Authors: Guerrero Gómez G 
Published: November 2019

Abstract
The air-fuel ratio necessary for coal combustion and the study of atmospheric emissions generated in an intermittent kiln of brickworks la Pradera were determined. A mass balance of the coal constituents and an isokinetic sampling of the gas emissions generated in the kiln were carried out. This was done according to the methodology and procedures established by “Ministerio de Ambiente, Vivienda y Desarrollo Territorial” in the protocol for the control and monitoring of atmospheric pollution generated by stationary sources. A combustion gas analyzer was used to measure the concentration of pollutants such as particulate matter, sulfur dioxide, nitrogen oxides, hydrochloric and hydrofluoric acids, and carbon dioxide and monoxide. The average concentrations of particle material, nitrogen oxides, sulfur dioxide, hydrochloric and hydrofluoric acids through the kiln chimney were 1228.60 mg/Nm3, 625.50 mg/Nm3, 563.10 mg/Nm3, 21.50 mg/Nm3 and 6.40 mg/Nm3 respectively, under reference conditions and adjusted to 18% oxygen. The kiln used has energy losses due to incomplete combustion of coal and sensible heat in the flue gases. The concentrations of nitrogen oxides, sulfur dioxides, and particulate matter are above the standard value and do not meet the permissible emission standard. On the other hand, halides do meet the respective standard.
Designing a stretcher artificial insemination, collection and transfer of embryos goats
Authors: García-León R A , Flórez-Solano E , Santiago-Bayona B D 
Published: November 2019

Abstract
The purpose of this work is to build a stretcher for artificial insemination, collection and transfer of embryos in goats taking into account the losses that have been identified in the population of these animals, where the female is injured in the process of attachment, generating losses of time by the operator trying to control the animal and this in turn leads to costs for the breeding laboratory. This is why, with the development of this work, the construction of a stretcher with pneumatic lift that mitigates the existing problem in goat production, which will allow the veterinarian to perform the process properly, achieving a practical adjustment in the height during the intervention.
Optimal thermobaric parameters determination of natural gas dehydration in LNG production
Authors: Fedorova E B , Mel’nikov V B , Gafarova E B , Fedorova V A 
Published: November 2019

Abstract
Gas dehydration is one of the main technological processes in natural gas treatment for pipeline transportation and LNG production. The main task of this research is to increase the efficiency of adsorption gas dehydration. This report presents the results of a comparative assessment and determination of the optimal thermobaric parameters of the process of natural gas dehydration with KSMG type of silica gel and NaA-BS type of zeolite-containing adsorbent. It has been shown that reducing the temperature of the natural gas before dehydration reduces the mass of loaded adsorbent, the mass of adsorber, the consumption of regeneration gas, cooling gases, and fuel gas for heating regeneration gas. Recommendations on the dehydration unit placement after pre-cooling stage in order to reduce capital and operating costs are given at the end of the article. The results are important in the design and modernization of technological processes of the LNG production.
Fretting fatigue and wear of mechanical joints: Literature study
Authors: Karlsen Ø , Lemu H G 
Published: November 2019

Abstract
Most mechanical connections are in one way or another exposed to some form of tear, wear, corrosion and fatigue, and likely to fail over time. If the contacting surfaces in a connection are exposed to tangential loading due to vibrations, small amplitude displacements called fretting can be induced at the surface, and might result in crack nucleation and possible propagation. The review and analysis reported herein are based on review of a wide range of studies reported in the literature during the last 25 years, which look into earlier studies around fretting fatigue in interference fit connections. In addition, a new method on how to obtain an interference fit is being mentioned as a possible way of increasing the joints fretting fatigue life. Previous investigations show clearly positive effects of finding and operating with the correct combinations of interference fit levels, palliative treatments and material choices to increase the fretting fatigue life.
Brief review on the limit state function of dynamic scour protections
Authors: Fazeres-Ferradosa T , Welzel M , Taveira-Pinto F , Rosa-Santos P , Chambel J 
Published: November 2019

Abstract
Offshore foundations, namely for offshore wind, wave and tidal applications, often require the use of scour protections. Rip-rap scour protections are an important element of the foundation to ensure that the natural frequency stays within the design limits. Scour protection design still presents a remarkable empirical nature, which typically leads to uncertainty on their behaviour under extreme met-ocean conditions. Therefore, reliability assessment of scour protections has been seen as a possibility to account for design uncertainty and to optimise the scour protections. However, the definition of a suitable limit state function is still a matter of research focus, namely, regarding the proper definition of the acceptable damage level for dynamic scour protections. This research provides a brief review on the recent studies related to both the limit state function and the calculation of damage numbers through bathymetric data. A discussion is raised on how the methodologies for calculating the damage number may influence the limit state function and a theoretical example is given to assess the effects on the probability of failure. Results have shown that the acceptable damage number requires a clearer definition, which should be based on the number of layers of rock material and the area of filter exposure. In addition, this research highlights the need for alternative ways to assess damage.
Investigation of updating methods for probability-informed inspection planning for offshore structures
Authors: Ersdal G , Oma N 
Published: November 2019

Abstract
The paper presents a novel process for probability-informed inspection planning based on the following principles. 1) A description of the strength of knowledge about a problem shall be included and be accounted for in the decision making, 2) Probabilistic methods should be used to predict quantities expressing the physical reality of nature (observable quantities) and their uncertainty, and 3) Any update of the probabilistic model should be limited to the actually observed quantities. The process for updating the probability of failure after inspection is programmed in accordance with these principles based on Monte-Carlo simulations and Bayesian parameter updating. The application of these principles and the proposed process is illustrated by an example calculation resulting in an example of inspection intervals for a jacket structure.
Time-variant rule-based reliability of corroded structures by Monte Carlo simulation
Authors: Neumann K M , Leira B , Vårdal O T , Ehlers S 
Published: November 2019

Abstract
General widespread corrosion is of increasing concern for structural reliability of ageing marine structures, particularly for semi-submersible pontoons. Conditional failure rate, also termed hazard function is sought to describe the increasing maintenance required with age. Literature is reviewed connecting corrosion degradation to hazard rate, either through a time degrading limit state function, or statistical data for time to failure. Here, a rule based failure definition is applied based on corrosion tolerance levels, together with a linear corrosion degradation model to make a time variant limit state function. Monte Carlo simulation is applied based on statistical models for the basic variables including importance sampling, to obtain the time to failure distribution from which the hazard curve is deduced. A more realistic hazard function is also produced, requiring average of 3 simulations to exceed the tolerance in order to fail. It is seen that this approach delays the increase of the hazard curve, at the expense of higher failure rates.