bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intermittency of many-particle dispersion in anisotropic magnetohydrodynamic turbulence
Authors: Pratt J. , Busse A. , Müller W.-C. 
Published: October 2020

AbstractIntermittent deviation from average dispersion curves reveals differences between the dynamics of magnetohydrodynamic turbulence and hydrodynamic turbulence. Turbulent dispersion is typically measured by the average separation of a group of Lagrangian tracer particles from each other as the particles move in a turbulent flow. On average, the particles will increase their separation as time evolves. However, due to the intermittent nature of turbulence, radical deviations from this behavior can be observed when considering individual groups of particles. When the group consists only of two particles, those two particles sometimes can move toward each other for short periods of time, decreasing their separation. When the group consists instead of many particles that are initially densely packed, similar results can be obtained using the convex hull of the group of particles. We examine this intermittency of many-particle dispersion in incompressible isotropic hydrodynamic turbulence, incompressible isotropic magnetohydrodynamic turbulence, and incompressible anisotropic magnetohydrodynamic turbulence. We interpret periods of decreasing separation physically in terms of anisotropic dispersion due to a large-scale static magnetic field, interactions with local magnetic fields and current sheets, and interactions with Alfvénic fluctuations.
Generalized non-linear Compton-Getting transformation for energetic particles: Applications throughout the heliosphere
Authors: Roelof Edmond C. 
Published: October 2020

Abstract
We develop the theoretical basis for a non-linear frame transformation of energetic ion intensity anisotropies (i.e., a generalized Compton-Getting transformation). Within the basic physics-motivated assumption that the anisotropies are gyrotropic in the transform frame, the rather general formulation allows us to examine a wide range of ion intensity distributions throughout the heliosphere. In addition to generalizing more familiar applications of the Compton-Getting transformation (that utilizes the bulk plasma velocity V for the transformation), we also apply the component (V^) transverse to the magnetic field (B). The physical justification is that (V^) is the ExB drift velocity with which the magnetic field lines “move”. In this paper, we have focused on two quite different areas: the elucidation of the strong field-aligned anisotropies and steep energy spectra being observed near the Sun from Parker Solar Probe (and Solar Orbiter), and the extraction of the bulk plasma velocity in the heliosheath at ∼100 AU using the anisotropies in energetic ion intensities observed on Voyager 1&2.
Interstellar Dust and Gas in the Heliosphere
Authors: Slavin Jonathan 
Published: October 2020

Abstract
Interstellar dust and gas that enter the heliosphere provide us with important clues about both the heliosphere and the local interstellar medium (LISM). The picture we have of the LIC from both in situ detections and absorption line data presents questions that have important implications for the origins and evolution of the cloud. New detections of 60Fe on Earth in deep sea crusts and Antarctic snow cores provide evidence for the role of supernovae in shaping the LISM. We discuss our models for the evolution of the LIC inside the Local Bubble and possible explanations for the source of the supernova produced dust.
Possible Evolution of Minifilament-Eruption-Produced Solar Coronal Jets, Jetlets, and Spicules, into Magnetic-Twist-Wave “Switchbacks” Observed by the Parker Solar Probe (PSP)
Authors: Sterling Alphonse C. , Moore Ronald L. , Panesar Navdeep K. , Samanta Tanmoy 
Published: October 2020

AbstractMany solar coronal jets result from erupting miniature-filament (“minifilament”) magnetic flux ropes that reconnect with encountered surrounding far-reaching field. Many of those minifilament flux ropes are apparently built and triggered to erupt by magnetic flux cancelation. If that cancelation (or some other process) results in the flux rope’s field having twist, then the reconnection with the far-reaching field transfers much of that twist to that reconnected far-reaching field. In cases where that surrounding field is open, the twist can propagate to far distances from the Sun as a magnetic-twist Alfvénic pulse. We argue that such pulses from jets could be the kinked-magnetic-field structures known as “switchbacks,” detected in the solar wind during perihelion passages of the Parker Solar Probe (PSP). For typical coronal-jet-generated Alfvénic pulses, we expect that the switchbacks would flow pastPSPwith a duration of several tens of minutes; larger coronal jets might produce switchbacks with passage durations ∼1hr. Smaller-scale jet-like features on the Sun known as “jetlets” may be small-scale versions of coronal jets, produced in a similar manner as the coronal jets. We estimate that switchbacks from jetlets would flow pastPSPwith a duration of a few minutes. Chromospheric spicules are jet-like features that are even smaller than jetlets. If some portion of their population are indeed very-small-scale versions of coronal jets, then we speculate that the same processes could result in switchbacks that passPSPwith durations ranging from about ∼2 min down to tens of seconds.
Perpendicular diffusion of solar energetic particles: When is the diffusion approximation valid?
Authors: Strauss R D , van den Berg J P , Steyn P J , Effenberger F J , Wijsen N , Laitinen T , le Roux J A 
Published: October 2020

Abstract
Multi-spacecraft observations of widespread solar energetic particle (SEP) events indicate that perpendicular (to the mean field) diffusion is an important SEP transport mechanism. However, this is in direct contrast to so-called spike and drop-out events, which indicate very little lateral transport. To better understand these seemingly incongruous observations, we discuss the recent progress made towards understanding and implementing perpendicular diffusion in transport models of SEP electrons. This includes a re-derivation of the relevant focused transport equation, a discussion surrounding the correct form of the pitch-angle dependent perpendicular diffusion coefficient and what turbulence quantities are needed as input, and how models lead to degenerate solutions of the particle intensity. Lastly, we evaluate the validity of a diffusion approach to SEP transport and conclude that it is valid when examining a large number of (an ensemble of) events, but that individual SEP events may exhibit coherent structures related to the magnetic field turbulence at short timescales that cannot be accounted for in this modelling approach.
XV Applied Mathematics Meeting and XII Statistics Meeting
Authors: Parra-López H M , Gómez-Vergel C S , Rojas-Suárez J P , Dueñas Ramírez L M 
Published: October 2020

The objective of the XV Applied Mathematics Meeting and XII Statistics Meeting was to promote a space for the exchange of knowledge between the academic and industrial sectors and physics; this event is a space to promote reflection and debate on mathematics, statistics, its history, evolution, didactics and application in physics and other sciences. In this meeting, researchers and teachers of mathematics interacted, socialized research results, consolidated networks for the exchange of ideas and successful experiences; moreover, these spaces allowed the strengthening of mathematics and statistics as a science. This science with its pedagogical principles promoted innovation and encouraged the creation of other learning scenarios; these scenarios are oriented to the application of mathematics in various areas of knowledge and to encourage students’ interest in research in these sciences.
List o Organizing Committee, National Scientific Committee, International Scientific Committee, Invited Speakers, Sponsor and Sponsor logos, Partners and Partners logos are also available in this pdf.
Statistical mechanics in the portfolio optimization with Kusuoka’s representation
Authors: Restrepo R , Herrera Y 
Published: October 2020

Abstract
Portfolio optimization under a risk measure consists of finding the efficient curve of the given measure in the plane of expected return vs risk. The portfolios corresponding to points of this curve are portfolios which minimize the risk under the given measure and whose expected total return is greater than a pre-specificied level (benchmark). The optimization problems involved are mostly non-convex and therefore cumbersome. In this paper, we provide a method to approximate the efficient frontier under a law-invariant coherent risk measure by relaxing these optimization problems involved to a finite-dimensional linear model. Our method is based on three tools: the Kusuokas’s representation of the risk measure, the properties of the conditional value at risk functions and the finite elements theory. Finally, we mention the strong connection that the former kind of optimization have with problems in statistical mechanics following the classic framework of simulating annealing.
Use of synthetic polymers of pumice for the removal of chromium in the tannery industry
Authors: Grillo J , Montaño A M , González C P 
Published: October 2020

Abstract
Synthetic inorganic polymers are materials called geopolymers that have structural characteristics used for the removal of contaminants in wastewater. Thanks to its easy synthesis and low production costs, they have become one of the most studied materials in removal processes. In the tannery industry, huge amounts of water are used, which are mixed with chromium salts and whose final disposal is made directly on the water slopes, becoming a serious environmental problem for the world. In this work, geopolymer synthesized with pumice was used to determine the efficiency in the removal of chromium in the wastewater of a tannery in the city of Bucaramanga, Colombia. Initially, aqueous solutions were prepared to study the influence of the contact time, the pH of the initial solution and the dose of adsorbent, on the removal capacity of the metal. The maximum adsorption was presented at nine hours and at a pH value of 4, by comparing the adsorption percentages it was found that the geopolymer has better removal capacity than the precursor material, in turn a study of the sorption kinetics using the Langmuir and Freundlich isotherm model were made. Obtained geopolymer and raw material were characterized by Fourier-transform infrared spectroscopy, X-ray diffraction and scanning electron microscope, before and after the adsorption process.
Physical mechanical performance of asphaltic emulsions in road oil for flexible pavements
Authors: Bastidas-Martínez J G , Ruge J C , Paba I J , Vasquez F , Rojas Suárez J P 
Published: October 2020

Abstract
The present study evaluated experimentally, the impact of the application rate, in terms physical and adherence, of four types of emulsions used as road oiling in two asphaltic layers for flexible pavements. Asphaltic layers are composed by an asphaltic base and a hot mix asphalt surface layer. To evaluate the adherence and physical properties, a shearing test was carried out. Four rapid set cationic emulsions were used, by means of three application rates of 0.33 l/m2, 0.50 l/m2, and 0.65 l/m2 (recommended values in Colombian road construction practices). The results demonstrate that an emulsion application rate of 0.50 l/m2 guarantees better adherence in the structural package. Also, that greater resistance against the sliding of the surfaces of the specimens in the shearing test, depends on the residual content of the asphaltic emulsion.
Improvements in the thermal behavior in the manufacture of the H10 block using coffee husks as an alternative industrial additive
Authors: Sánchez-Zúñiga J V , Sánchez-Molina J , Díaz-Fuentes C X 
Published: October 2020

Abstract
Industrial organic waste reuse in product manufacturing processes is a strategy that strengthens the circular economy. Thanks to materials science, the coffee husk is considered a sustainable alternative that promotes industrial processes optimization in the ceramic industry and contributes to the energy efficiency of buildings. This paper summarizes the behavior of H10 blocks on a laboratory scale in 2 mixtures of clay and coffee husk fired in 3 different temperatures: 900 °C, 1000 °C, and 1100 °C, at the “Centro de Investigación en Materiales Cerámicos, Universidad Francisco de Paula Santander”, Colombia; and evaluates the relationship of physical and mechanical properties with thermal behavior by heat transfer and heat fluxes, simulated in the analysis system software through the finite element method. The results support the improvement of thermal insulation capacity. Due to this, coffee husk combustion generates internal air chambers that increase the porosity of the product. In spite of, physical and mechanical properties contrast thermal benefits with increasing water absorption percentages and thus decreasing the compressive strength of samples. In conclusion, new materials development is a technological advance that expands possibilities to create new solutions for buildings and even improves standardized designs in the ceramic industry.
Design of a portable, low-cost, heliodon prototype for the teaching of solar geometry and irradiance in bioclimatic architecture
Authors: Moreno Peña J R , Contreras Galván B G , Ortega Valencia J C , Pineda Torres J A , Bricio Barrios E E , Arceo Díaz S 
Published: October 2020

Abstract
The design of a portable, low-cost heliodon, developed for didactic purposes, is shown. Students can represent the solar path through the sky, relative to geographical coordinates in any hour and date, by the combined movement of a light source along an arc and its rotation around two different axes. The prototype can be controlled either manually or through a computer application. Following its intrinsic motivation in teaching, this prototype serves to introduce architecture students to bioclimatic architecture, for the design of edifications with a low energy use index, and solar charts, while it can also be a valuable tool in helping to improve the understanding of engineering, physics and astronomy students on topics related to physical computing, solar geometry, irradiance and heat transport.
Real teaching situations to encourage the learning of fractions from physics
Authors: Galvis Burgos M I , Gallardo Pérez H J , Villamizar Jaimes D 
Published: October 2020

AbstractThe research aims to implement real didactic situations for learning fractions and physics in students from educational institutions in “San José de Cúcuta, Norte de Santander, Colombia”. From the theoretical point of view, it starts from one of the ideas that have been emerging in recent times regarding the teaching of physics, such as the development of physical-mathematical thinking by inserting the paradigm of didactic situations into the educational environment. The research is part of a field study, quasi-experimental with self-control. The treatment plan was organized in five didactic situations on theoretical and practical aspects of physics. The results of the pretest reflect deficiencies in the use of mathematical contents associated to the description of physical phenomena in the population under study, which allowed the design and implementation of a pedagogical intervention plan. The post-test showed an increase in the execution of mathematical models in the application to physical phenomena, which inferred the effectiveness of the intervention plan, whose activities allowed innovation in the classroom to achieve the students’ attention. It is concluded that the didactic proposal was an enriching experience with the active participation of the students.
Control panels in human talent processes for professionals in physics in public organizations
Authors: Rojas Suárez J P , Gónzalez Mendoza J , Vergel Ortega M 
Published: October 2020

Abstract
The research follows a cross-sectional inferential quantitative approach, supported by qualitative analysis. Its objective is to evaluate, based on T2 Hotelling, the quality of the human talent process in professionals in physic, through observation of sub-processes and service provided by public servants. The diagnosis was made using the techniques of interview, Delphi and expert audit applied to a sample of 200 users in public institutions in process executed by professionals in physics, and 3 experts in human talent during the year 2019. Results show imaginaries that affect the quality of the process human talent focused on selection of the public servant, bureaucratic processes, waiting time and negative attitudes that affect the perception of these professionals; Bayesian control limits calculated with the distribution of predictive probability posteriori, does not show signs that the process is out of control, but shows three alarms, whose adjustment of parameters through robust methods leads to obtaining a behavior protected from outliers, it was conclusion is that the behavior of the human talent process in institutions and entities in which public servants work in Colombia is under control.
Proposal to evaluate the load capacity of bridges subjected to bending and shear due to living load traffic
Authors: Pino Lobo M , Afanador García N , Guerrero Gómez G 
Published: October 2020

Abstract
This research work reflects the procedure to evaluate the classification factors associated with the load capacity of existing reinforced concrete bridges in Colombia, taking as a case study a bridge simply supported by reinforced concrete with a span of 12 m, determined the physical relationship between the nominal flexion of the element and the flexion due to live load for the bridge under study, for which the established criteria were accepted is the philosophy based on load and resistance factor rating recorded in the manual for evaluation of bridges of the American Association of State Highway and Transportation Officials, concluding that the procedure implemented is consistent with the criteria established in the bridge design manual in Colombia based on the reliable use of statistical factors and the theory of probabilities for the development of bridge designs such structures.
Financial Feasibility Analysis of Jasmine Flower (Jasminum Sambac L.) Farming Business in Batang Regency, Central Java
Authors: Prasetyo Edy , Ekowati Titik , Mukson  , Gayatri Siwi 
Published: October 2020

Abstract
The objectives of the research were to: (i) analyze the productivity of jasmine flower farming business; (ii) analyze the production cost, revenue, and income of jasmine flower farming business; and (iii) analyze the financial feasibility of jasmine flower farming business in Batang Regency. Survey method was used among farmers of jasmine flower in Batang Regency. The sampling method was Purposive Quota Non Probability Sampling Method with the number of samples was 63 respondents. The data was analyzed by descriptive qualitative, descriptive quantitative using statistic i.e. data tabulation, business financial analysis, and analysis of One-Sample t-Test. The result of the research shows that: (i) average scale of jasmine flower farming business in Batang Regency was 0.499 acre/farmer with the productivity of 2,793.86 kg/year, or equal to 5,598.92 kg/acre/year; (ii) the value of jasmine flower farming business income was of Rp 36,999,466.74/0.499 acre/year, or equal to the value of Rp 74,147,277.93/acre/year; and (iii) comparison result with Regency’s Minimum Wage and the Level of Deposit Interest Rate shows that jasmine flower farming business had a potential and was feasible to run and developed in Batang Regency.
Relationship between teat dimensions and milking efficiency by hand milking on dairy cows in Temanggung Regency
Authors: Hartanto Rudy , Listya Damayanti Renita , Sambodho Priyo , Moch Sayuthi Suranto 
Published: October 2020

Abstract
This research was completed at PT. Naksatra Kejora, Temanggung Regency, Central Java Province, Indonesia using 31Holstein Friesian cows (lactation period I-V and lactation month 1-10). The observational method was used in this study. The parameters measured were teat dimensions (teat volume as X1, teat circumference as X2, and teat length as X3) as independent variable and milking efficiency (milking time duration / milk production as Y) as dependent variable. Data obtained were analyzed using correlation, then using linear multiple regression to predict the milking efficiency from teat dimensions. Analysis of variance was used to test the significance of model. The result showed that there was no significant relationship between milking efficiency with teat volume (R = 0.070), teat circumference (R = 0.226) and teat length (R = -0.090). The multiple regression model was Y = 1.141 + 0.003 X1+ 0.050X2- 0.092 X3 (R2 = 0.236, no significant P = 0.061). It was concluded that it was difficult to predict the milking efficiency from teat dimensions on Holstein Friesian cow in Temanggung Regency.
Nitrogen Fertilizer and Microbial Inoculations Determined the Nutrient Uptake and Productivity of Soybean
Authors: Bientri Yunindanova Mercy , Djoko Sulistyo Trijono , Daidi Jauhari Muhammad 
Published: October 2020

Abstract
Soybean is an important commodity in Indonesia. This study aimed to identify the application of microbe inoculations with dosage of N in form of urea toward the growth, N uptake and yield in soybean. This research was conducted on October 2017 to January 2018 in Panunggalan village, Pulokulon, Grobogan, Central Java. It used the Randomized Complete Block Design 2 factors: urea dosages (0; 50; 100 kg ha−1) and microbe inoculations (no inoculation; Rhizobium (R); Rhizobium + Trichoderma (R+T); Trichoderma(T)). The result showed that combination of urea dosage and microbe inoculations significantly influenced plant height and number of trifoliate leaves. Urea dosages and microbe inoculations or combination of both factors did not imply nodulation process. Higher N dosage and microbe inoculations increased N uptake of biomass on vegetative period but had no effect on flowering and pod filling periods. The combination of 100 kgHa-1 urea with microbes or without microbes produced the highest productivity. However, treatment without urea and no inoculation also achieved the highest production. This suggested that there was a native population of Rhizobium bacteria strains that effectively supplied N for plants. Besides, application of urea of 100 kg ha-1 or 46 N kg ha-1 was too small to interfere fixation nitrogen by local Rhizobium population. Therefore, N application in form of anorganic fertilizer or microbe for symbiotic N-fixation was not recommended for existing agro climatic conditions of area with soybean history. Thus, it could simultaneously save the cost of agricultural production.