bluuebunny/crossref_metadata_2025 huggingface dataset:
Alternative approaches in digital era to handle undergraduate physics (mechanics) laboratory: a case study of moment of inertia of a flywheel experiment
Authors: Sharma S , Ahluwalia P K
Published: June 2020

With the invasion of Digital Era on all activities of life, alternative approaches are emerging to explore a single situation in many ways, offering new opportunities and insights about learning behaviour of the student. It is expected that this is going to impact traditional laboratory practices in different ways. The moot question is: can these alternative explorations be used for enhancing learning experiences of the learners, make laboratory a more engaging place and tuning learners’ alternative conceptions with the conceptions of an expert. In this case study, we present three ways to perform an experiment to calculate the moment of inertia of a flywheel in a typical undergraduate Mechanics (Physics) laboratory: (i) the traditional way using a stopwatch and a meter rod as basic measuring tools, (ii) by using a video analyser of a typical setup of the experiment and (iii) a modelling software available in a web-based virtual laboratory. The physics education research strategies are applied to observe the pedagogical value of performing the same experiment in three ways together. To go ahead with this approach, implemented through pre-post-test methodology, a concept inventory has been devised to identify the alternative conceptions around the moment of inertia, theorems of the moment of inertia and flywheel as a mechanical device to control rotational motion in a daily life. An effort has been made to address the alternative conceptions during the performance of the same experiment in three distinct ways. Finally, a perception survey was also carried out to know about this multi-representational approach’s (a) pedagogical effectiveness, (b) effect on laboratory climate, (c) expectations of students, (d) laboratory engagement and (e) instructor-student relationship.
Death of an outcome – consequences of stigmergy in our examinations
Authors: Clerk D P P , Naidoo D
Published: June 2020

This paper reports on an analysis of questions in physics examination papers at matriculation and first-year university level. The intention is to throw light on an on-going concern, sometimes expressed by university level physics instructors, that there is a general weakness in problem-solving ability among their students. This begs several questions; the first and most obvious one being what we mean by ‘problem-solving’. The second is whether this perceived weakness has an objective reality. Evidence supporting this can be found in both the literature and in examination results. The third question asks what might be causing this state of affairs. To attempt to answer this, examination papers at both matriculation and university level (first-year) were analysed with a view to finding what types of questions are typically asked, and to ascertain whether there may perhaps be a bias in favour of - or against - specific types of question. The evidence shows that there is indeed a favoured question-type that can be explicitly taught, and relatively easily mastered - and which typically makes up a sufficiently large fraction of an examination that a candidate can pass the examination without having to demonstrate any real problem-solving ability. What an examination candidate does need to demonstrate is a well-developed ability to expedite routine operations at various levels of complexity, which - depending on one’s espoused definition - does not amount to problem-solving. The bias away from novel (or heuristic) problem-solving is here seen as a stigmergic sign that indicates to candidates, instructors and examiners alike that the ability to deal with novelty, which is the essence of problem-solving, is not needed in order to pass - or even to do well in - these high-stakes examinations. Hence the need either to teach or to learn problem-solving could come to be seen as unnecessary. This state of affairs is repeated - and hence reinforced - at each successive annual iteration.
A study of student teachers’ misconceptions on uniform circular motion
Authors: Mutsvangwa A
Published: June 2020

Uniform circular motion is one of the key mechanics topics in Physics that students fail to comprehend and master. In South Africa, uniform circular motion is currently not taught to Physical Sciences Matriculate learners and thus students are only introduced to it at university level. It is appreciated that poor comprehension of fundamental concepts and tenets of uniform circular motion leads to difficulties in understanding related topics such as Rotational Kinematics and Rotational Dynamics. This study investigated student teachers’ misconceptions about uniform circular motion and its pertinent underlying concepts such as tangential acceleration and centripetal acceleration. The study also attempted to figure out the source(s) of the ensuing misconceptions. The sample of the study consisted of 41 second-year Physical Sciences student teachers at a South African university. A multiple-choice test consisting of 20 questions on uniform circular motion was administered. Simple and explanatory statistical techniques were employed to analyse the data and appropriate intervention methods were proposed to curtail the identified misconceptions. The study revealed that factual misconceptions and conceptual misunderstandings were prevalent amongst the student teachers who took part in the research exercise.
Teaching physics in the discipline of medical radiations in an Australian university
Authors: Deb Pradip
Published: June 2020

Medical radiations and imaging are highly technologically driven professions. Adequate knowledge in physics is the basic requirement for any medical radiation technologists working in medical radiation centres where ionizing radiations are used. The purpose of this paper is to discuss courses of physics we teach and the challenges we face in teaching physics to the undergraduate students in the discipline of medical radiations in our university. Although laws of physics are applied in the development and use of diagnostic and therapeutic medical equipment, the physics is not loved by the students as a subject as it should be. Several medical radiations physics courses are taught in undergraduate medical radiations program in our discipline including radiography, nuclear medicine, radiotherapy, CT, MRI, and Ultrasonography. In this paper teaching methods of medical radiation physics are discussed and students’ approach to learn this subject are analysed. The teaching techniques and initiatives are discussed along with their success and failure.
Schooling Africa: Computational Materials Science education and research
Authors: Chetty N. , Martin R M
Published: June 2020

The African School of Electronic Structure Methods and Applications (ASESMA) [1 – 7] is a series of workshops held every two years in different sub-Saharan countries, designed to foster a collaborative network for research and higher education in Africa. Participants are drawn from across the continent through a competitive process, and the lecturers and mentors are outstanding scientists from across the world including Africa. ASESMA is administered by the International Centre for Theoretical Physics (ICTP), and the primary sponsor is the International Union of Pure and Applied Physics (IUPAP). The core guiding principle is that computation makes it possible for world-class research to be done with modest investment, and it is an essential part of education for the future. The skills acquired are useful for teaching at the university level and are transferable to other disciplines. The participants are the teachers who will educate future generations of African scientists.
Physics education for 21st century graduates
Authors: Grayson D J
Published: June 2020

The 21st century world in which today’s students are growing up is different in a number of important ways from last century. It is characterised by ubiquitous and increasingly sophisticated technology, accelerating climate change, globalisation, and the concentration of the bulk of the world’s wealth in the hands of an ever-decreasing percentage of its population. There was also the great recession of 2008. Taken together, these things are impacting on students’ thinking patterns, behaviours, expectations, constraints and opportunities. Broad global developments, such as the fourth industrial revolution, the United Nations Sustainable Development Goals, as well as the recent rise of so-called fake news and popular rejection of evidence-based thinking, frame the context for what we can and must do in educating our students. What are the implications for physics and physics teaching? Physicists have always maintained that learning physics develops ways of thinking and solving problems that have broad applicability. While that may be true, no human endeavour can ever be divorced from context. How is the teaching of physics being affected by the global context, and how can physics teaching contribute to addressing global challenges? In this paper, I present key characteristics of who we are teaching, and make suggestions, in broad terms, about what and how we should teach in order to equip our students to be successful 21st graduates. That involves being able to navigate the complexities and uncertainties of a turbulent world, today and tomorrow, and, hopefully, contribute to making it a better place for all of its inhabitants.
Factorization of the Riesz-Feller Fractional Quantum Harmonic Oscillators
Authors: Rosu H C , Mancas S C
Published: June 2020

Using the Riesz-Feller fractional derivative, we apply the factorization algorithm to the fractional quantum harmonic oscillator along the lines previously proposed by Olivar-Romero and Rosas-Ortiz, extending their results. We solve the non-Hermitian fractional eigenvalue problem in the k space by introducing in that space a new class of Hermite ‘polynomials’ that we call Riesz-Feller Hermite ‘polynomials’. Using the inverse Fourier transform in Mathematica, interesting analytic results for the same eigenvalue problem in the x space are also obtained. Additionally, a more general factorization with two different Lévy indices is briefly introduced.
Is a Deterministic and Local Interpretation of Quantum Mechanics Possible?… First Steps
Authors: Nahmad-Achar E , Sánchez-Kuntz N
Published: June 2020

Quantum states in superposition cannot be observed, suggesting that they merely embody information on possible measurement results. Yet, we think of them as describing physical systems that evolve in time according to given mathematical equations. Furthermore, evolution takes place in physical space-time, and local causality is imposed on space-time by Special Relativity (a sequence of cause and effect that constitutes a fundamental principle by which we think about and do scientific work).

It is therefore strange that there is non–locality and violation of causality embedded in Quantum Mechanics. We try to give here a first step to see whether a deterministic and local interpretation is possible. We will show that Bell’s inequality is not conclusive about the non–local nature of Quantum Mechanics, in that there exists an interpretation of reality (which we put forward) which is local and in which Bell’s inequality cannot be derived. Assuming determinism and locality a new Bell-like inequality is derived, which is always satisfied by Quantum Mechanics and which allows for local hidden variables [1].
From Free Motion on a 3-Sphere to the Zernike System of Wavefronts Inside a Circular Pupil
Authors: Wolf K B
Published: June 2020

Classical or quantum systems that stem from a basic symmetry are seen to be special in having several important properties. The harmonic oscillator and the Bohr system are such. Recent research into the Zernike system provides reasons to include it in this privileged class. Here we show that free motion on the 3-sphere can be projected down to produce classical orbits or complete and orthogonal bases for wavefronts in a circular pupil. This line of inquiry has been pursued in company with N.M. Atakishiyev, G.S. Pogosyan, C. Salto-Alegre, and A. Yakhno.
Linearized Optomechanics Under Time-Dependent Phase Driving
Authors: Jaramillo Ávila B , Ventura-Velázquez C , Rodríguez-Lara B M
Published: June 2020

We study the effect of steepness in smooth phase changes in the laser that drives an optomechanical system in the red-detuned, linearized regime. These phase changes take the semi-classical component out of its steady state. Steeper phase changes produce larger amplitudes for the fast oscillations in the mean fields. In contrast, sufficiently slow phase changes keep the system close to its steady state and allow the implementation of a phase driving scheme designed to minimize the variation of the quantum fluctuation mean excitation values.
Nonstationary Deformed Singular Oscillator: Quantum Invariants and the Factorization Method
Authors: Zelaya K
Published: June 2020

New families of time-dependent potentials related with the stationary singular oscillator are introduced. This is achieved after noticing that a nonstationary quantum invariant can be constructed for the singular oscillator. Such a quantum invariant depends on coefficients related to solutions of the Ermakov equation, where the latter guarantees the regularity of the solutions at each time. In this form, after applying the factorization method to the quantum invariant rather than to the Hamiltonian, one manages to introduce the time parameter into the transformation, leading to factorized operators that become the constants of motion for the new time-dependent Hamiltonians. At the appropriate limit, the initial quantum invariant reproduces the stationary singular oscillator Hamiltonian. Some families of stationary potentials already reported by other authors are also recovered as particular cases. A striking feature of the method is that the singular barrier of the potential can be managed to vanish, which leads to non-singular time-dependent potentials.
New Families of Single—Qubit Control Fields: An Algorithm
Authors: Enríquez M , Jaimes-Nájera A
Published: June 2020

The dynamics of a two-level system interacting with a new class of analytically solvable driving fields is analyzed. Such fields are obtained using an inverse-engineering approach, which allows to exactly factorize the correspondent time-evolution operator via the Wei-Norman theorem. This technique is presented as an algorithm and using an example we show that the free parameters involved can be used to tune some aspects of the dynamics on demand such as the atomic population inversion.
Response of the Fractional Damped Oscillator to a Driving Delta Pulse
Authors: Olivar-Romero F
Published: June 2020

Exact solutions for a fractional damped oscillator that is acted by a Dirac delta pulse are reported. It is found that the response of the oscillator to such a pulse can be manipulated by either the damping parameter or the fractional order of the corresponding dynamical law.
Unitary Operators Over Quantum Systems with Several Levels
Authors: Morales-Luna G
Published: June 2020

High-dimensional quantum states generalise multi-valued logics. The analogous of Pauli transformations acting on these quantum states determine a subgroup structure in U(n), which acts over the maximally entangled Bell states. These properties are suitable to produce superdense coding communication protocols.
Some Remarks on the Local Unitary Classification of Three-Qubit Pure States
Authors: Luna-Hernández S
Published: June 2020

Characterization of multipartite entanglement is in general a challenging task. The entanglement polytope is particularly useful to study three-qubit systems since it allows a qualitative analysis of the related non-local properties from a geometric perspective. In this work, using numerical approaches, we show that there exist a correspondence between some classes of entanglement and some specific regions of the polytope for three-qubit systems.
Quantum Entanglement in Fenna—Matthews—Olson Photosynthetic Light—Harvesting complexes: A Short Review of Analysis Methods
Authors: González-Soria B , Delgado F
Published: June 2020

The Fenna-Matthews-Olson light-harvesting complexes have become a center of attention due to their high excitation energy transfer efficiency, which may surpass 98%. Experimental results reveal the presence of quantum entanglement in the protein structure, which seems to be associated to such a remarkably high efficiency. Notably, Redfield and Lindblad master equations have been already used to model the chromophore excitation in the protein complex as well as its interactions with the environment. The entanglement arising during the process has been quantified through several measures. This work provides a short review of methods used to model the above described system. It is also discussed the introduction of two nonconventional measures addresed to quantify the emergent entanglement.
Truncated Radial Oscillators with a Bound State in the Continuum via Darboux Transformations
Authors: López-Mejía L , Fernández-García N
Published: June 2020

The radial oscillator with zero angular momentum is used to construct a short-range model by cutting-off the potential at a given radius r = b, and by substituting it with a constant potential for r > b. The new potential, called truncated radial oscillator, admits both bound and scattering states. It is shown that the appropriate Darboux transformation leads to new exactly solvable models that have the entire energy spectrum of the truncated radial oscillator plus a new discrete energy eigenvalue. The latter defines a square-integrable wave function for the new system although it is embedded in the scattering regime of the energy spectrum. The new potentials are radial and such that their asymptotic behavior coincides with the profile predicted by von Neumann and Wigner for a potential to admit an eigenvalue in the continuum.
Design and Construction of Homodyne Detectors for the Study of Quantum Optical States
Authors: Barrios-Barocio E , Velázquez V , Cruz y Cruz S
Published: June 2020

Nowadays the fields of Quantum Optics and Quantum Information are experiencing a mayor development worldwide, in particular, in the experimental arena. The reason relies in the high perspectives of application of these fields in areas as computing, security, telecommunications and metrology, among others. A determinant fact for the experimental and technological development is the ability to design and construct electronic devices suitable for the study of light with quantum features, as well as the software which is necessary for the analysis and processing of experimental data. In this work we present a general overview of the theory, practical design and experimental tests of one of such devices called Homodyne Detector addressed to the study and engineering of quantum states of light.
XVI National Meeting on Optics and VII Andean and Caribbean Conference on Optics and its Applications
Authors: Rueda E , Castañeda-Sepúlveda R , Sandoval-Amador A , V-Niño E D
Published: June 2020

The XVI National Meeting on Optics and VII Andean and Caribbean Conference on Optics and its applications (XVI ENO - VII CANCOA) were successfully held together from 26th to 30th of November, 2019, at the Universidad de Cordoba, Montería, Colombia. The events brought together Colombian and Latin-American students, professionals, and researchers with interests on optics and photonics, thus offering them the opportunity to share and discuss their last research and findings, as well as to facilitate and encourage their mutual cooperation. This Proceedings issue compiles oral and poster presentations that were submitted by the authors and rigorously reviewed by a special committee designated by the Journal of Physics Conference Series (JPCS) editor for Colombian Conferences led by the Foundation of Researches in Science and Technology of Materials (FORISTOM).

In order to organize the XVI ENO - VII CANCOA according to the slogan Light and optics for the Colombian Caribbean Region, the “Red Colombiana de Óptica (RCO)” with the sponsor of the universities at the Colombian Caribbean Region. The main goal was to present the Colombian Caribbean as a region with growing interests and maturity in topics related to optics and photonics. A total of 63 oral presentations and 22 posters were presented. Four recognitions were given: two of them for undergraduate presentations and the other two for graduate presentations.

The RCO is a nonprofit society that seeks the strengthening of collaborations between researchers in optics, photonics, and spectroscopy in Colombia. It also encourages the dissemination of knowledge in optics, photonics, and spectroscopy in all areas of knowledge. More information about the network can be found on the webpage www.srco.org.co.

The National Meeting on Optics was created to facilitate the exchange of ideas between Colombian researchers on optics and photonics. The first meeting was held in 1987 in Medellín, Colombia and has been realized without interruption with two-year of periodicity.

The organizing and editorial committee of the XVI ENO - VII CANCOA hopes you enjoy the reading of this volume of the JPCS. Besides, we wish to thank all authors and participants for providing their valuable contributions for this proceeding as well as the reviewers for their constructive recommendations and criticism aiding to improve the presented articles. Likewise, we are confident that this issue will serve as a reference for optics, spectroscopy and photonics research in Colombia and Latin-America.

List of Organizing Committee, Scientific Committee, Editorial Committee, Invited Speakers, Organizing Institutions, Sponsors, Logos, Photos are available in this pdf.
Optimization of phase masks using simulated annealing algorithm for mode conversion
Authors: Gallego-Ruiz R D , Álvarez-Castaño M I , Herrera-Ramírez J A , Correa N A
Published: June 2020

The simulated annealing algorithm was applied for optimizing binary phase masks used in the conversion of optical modes through spatial light modulation in free space. The method changes the phase distribution to be displayed on a spatial light modulator, in such a way maximizes the correlation between de converted mode and the theoretical mode. The method allowed the optimal conversion of the linearly polarized modes through a diffractive process. The analysis of the correlations between obtained and theoretical modes showed the effectiveness of the method and its capability to generate optical modes similar to those in an optical fiber. The optimized phase masks could be applied in a dynamic and arbitrary mode converter.
Implementation of laser-induced breakdown spectroscopy technique for qualitative analysis of an austenitic steel
Authors: Toro L , Pacheco P , Álvarez J , Sarmiento R
Published: June 2020

In this work was used laser induced breakdown spectroscopy to study and characterize a sample of austenitic, steel American Iron and Steel Institute nomenclature, 304 series, with the objective of identifying constituent elements in the material. The steel was chosen because it is an economic and multipurpose material, which due to its physical characteristics, it is of great interest in the construction industry, design of tools and mechanical equipment. The contributions of this research to the industrial and metallurgical sector is that the laser induced breakdown spectroscopy technique allows to reduce costs in the experimental execution for qualitative studies of steels. Plasma generation was performed by focusing the radiation laser on the surface of a sample of steel. Plasma radiation generated was conducted through an optical fiber to a Mechelle spectrograph attached to an Intensified charge coupled device camera. The information obtained through the spectra allowed the characterization of the plasma by means of the parameters electronic temperature and electronic density, as well as the elementary identification of constituents of the steel sample, allowing identify major elements such as chromium, nickel, manganese and silicon, being concordant with the composition of elements present in the austenitic steel.
Surface enhanced Raman scattering of some nanotechnological material systems: A computational approach
Authors: Pérez F R , Merlano A S , Silva W , Salazar Á
Published: June 2020

Surface enhanced Raman spectroscopy or scattering, is an old analytical technique having multiple applications, but it still remains with great challenges. The complex physical and chemical processes involved results in difficulties for modelling and experimentation. In this work, numerical results of surface enhanced Raman spectroscopy spectra for some systems of interest in nanoscience and nanotechnology, monochlorobiphenyl isomers, graphene, magnetite and graphene oxide, are presented and discussed. A single gold nanoparticle and a dimer gold nanoparticle were utilized as surface-enhanced Raman spectroscopy substrates. The possibility of predicting structural properties of graphene oxide from comparison between its experimental and simulated Raman spectra is discussed. A relation between the enhancement factor for the G band of graphene oxide and the radius of a spherical nanoparticle dimer of gold, is suggested.
Optical and morphological properties of Au@Ag core-shell nanoparticles: Influence of different reducing agents
Authors: Merlano A S , Pérez F R , Silva W , Escobar N , Hoyos L M , Salazar A
Published: June 2020

Colloidal suspensions of gold coated with silver core-shell nanoparticles in poly vinyl alcohol were prepared by the seed-mediated growth approach and a comparative study of optical and morphological properties was conducted. Two types of gold seeds were considered. For the first type, a strong reducing agent (NaBH4) and for the second one, a weak reducing agent (Na3C6H5O7) were used. Four volumes of AgNO3 solution were used to obtain silver coatings with different thicknesses. In each case, morphological and optical properties were investigated by transmission electron microscopy and ultraviolet–visible spectroscopy, respectively. Also, numerical calculations of optical absorption were performed with Matlab toolbox for the simulation of metallic nanoparticles, using a boundary element method approach. This study offers practical considerations useful as a route of synthesis at room temperature of this type of nanoparticles, in such a way that a good homogeneity and reproducibility can be achieved. Results here presented show practical details useful in the synthesis of this type of nanoparticles for applications such as catalysis.
Acquisition and evaluation of depth data from humans, in robotized industrial environments
Authors: Nieto W , Arias-Correa M , Madrigal-González C
Published: June 2020

Industry 4.0 places great importance on collaborative robotics in industrial production and, therefore, on the safe interaction between humans and robots. In previous decades, robots that were part of flexible manufacturing systems remained isolated from human operators through physical enclosures, but current human-robot collaboration activities require a simultaneous concurrent workspace for both actors. Collaborative robotics security systems have used (among others) artificial vision systems based on red, green and blue additive color model images, as proven solutions in detecting humans within the work area of robots. In recent work, the combination of red, green, and blue additive color model imaging with depth imaging systems has demonstrated low sensitivity to lighting changes and a high positional match between distance data and color pixels in both types of acquired images. However, a detailed review resulted in the absence of databases of industrial robotic environments in this type of images. In this paper, an extensive database is delivered in the format already explained that contains people in robotic industrial settings. Furthermore, evaluating the database using machine learning techniques enables computer vision researchers to gain a better understanding of human detection using a Kinect sensor and convolutional neural networks.
A validation strategy for a target-based vision tracking system with an industrial robot
Authors: Romero C , Naufal C , Meza J , Marrugo A G
Published: June 2020

Computer vision tracking systems are used in many medical and industrial applications. Understanding and modeling the tracking errors for a given system aids in the correct implementation and operation for optimal measurement results. This project aims to simulate and experimentally validate a tracking system for medical imaging. In this work, we developed a validation strategy for a target-based vision tracking system with an industrial robot. The simulation results show that the system can be accurately modeled, and the error assessment strategy is robust. Experimental verification with an EPSON C3 robot shows the reliability of the vision tracking system to obtain the target position and pose accurately. The general-purpose performance assessment strategy can be used as a vision tracking evaluation mechanism to ensure the system performance is adequate for a given application.
Plasmon modes characterization in hybrid noble/ ferromagnetic nanodisks using an effective medium approximation
Authors: Herreño-Fierro C A , Zapata-Herrera M
Published: June 2020

Magneto-plasmonic systems composed by noble/ferromagnetic metals structures can be used to control light polarization. The extraordinary optical properties arising from combining strong local enhancements of electromagnetic fields in surface plasmon excitations with the magneto-optical activity inherent to ferromagnetic materials, can be controlled by external magnetic fields that have demonstrated the possibility to control and amplify the magneto-optical properties via plasmonic excitations. In this work, the anisotropic optical and ellipsometric sensitivity to dielectric environment of multi-layered hybrid gold/cobalt magnetoplasmonic nanodisks are studied in the framework of the effective-medium approximation, where the components of the dielectric tensor of the system are modelled using Lorentz-like oscillators. Furthermore, full electromagnetic simulations were performed using the standard Finite Element Method, which allow us to characterize the modes and explore the role of the dielectric environment of the nanodisks in the optical properties of the nanostructures via the variation of a coating silicon dioxide (SiO2) layer thickness. Our model and numerical results show a very good agreement with spectral ellipsometry measurements, where two orthogonal plasmonic modes one in-plane and one out-of-plane- are well characterized. These results lead us to conclude that the effective-medium approximation is good enough to accurately describe the plasmonic behavior of multi-layered confined nanostructures.
Automatic recognition of Colombian car license plates using convolutional neural networks and Chars74k database
Authors: Arroyo-Pérez D E , Álvarez-Canchila O I , Patiño-Saucedo A , Rostro González H , Patiño-Vanegas A
Published: June 2020

A methodology for the automatic recognition of Colombian car license plates using convolutional neural networks is proposed. One of the biggest challenges when using onvolutional neural network is the demand for large amounts of samples for training. In this work, we show that if we do not have enough images of vehicle license plates to carry out the training, we can complement it with databases of letters and numbers that are not extracted from cars. The network was trained with the Chars74k database and images of characters extracted from plates of Colombian automobiles. The Chars74k contains approximately 74000 images of all the letters of the Spanish alphabet and all digits from 0 to 9. From chars74k database we have chosen 33849, because the Colombian plates have only uppercase letters and digits. Only 3549 (about 10% of the total) images of characters extracted manually from plates of Colombian automobiles were added. At the input of the convolutional neural network, 70% of the images were used for training, 20% for validation and 10% for testing and the resulting validation accuracy was above 99%. By making a preliminary test on Colombian plates never before used in training, a percentage of correctly recognized plates above 98% was achieved.
Optical properties of a simple model of soft biological tissue
Authors: Fajardo C , Solarte E
Published: June 2020

Optical phantoms that simulate light propagation processes through soft biological tissue are required to evaluate the performance and calibrate different medical imaging modalities. Liquid lipid based low-cost phantoms were prepared, with cow’s milk as scattering material, red India ink as the absorbing material and demineralized water as the matrix material since it provides a soft medium biologically compatible with the addition of organic molecules. Two experiments were carried out for characterization of this soft tissue model. First, collimated and diffuse transmittance and reflectance spectra were measured using phantoms with milk of different fat content. From the data, dependence between: total extinction coefficient, Kubelka Munk’s ratio, absorption and scattering coefficients on the wavelength were estimated. Second, using collimated transmittance measurements the effect of the phantom components was observed. The absorption peak, around 550 ± 0.3 nm, increases as ink was added to milk phantoms; and when lipid concentration was varied, by fixed ink, the scattering growths. The extinction coefficient’s dependence on the wavelength was determined, and fluorescence was observed with a 31 ± 0.3 nm Stokes shift. Results confirm the possibility of spectroscopic identification of milk kinds, as well as the feasibility of low cost controllable phantom for preliminary biophotonic studies.
Results from the PolarquEEEst missions
Authors: Abbrescia M. , Avanzini C. , Balbi G. , Baldini L. , Baldini Ferroli R. , Batignani G. , Battaglieri M. , Boi S. , Cavazza D. , Bossini E. , Carnesecchi F. , Cicalò C. , Cifarelli L. , Coccetti F. , Coccia E. , Corvaglia A. , De Gruttola D. , De Pasquale S. , Fabbri F. , Falchieri D. , Flammini A. , Galante L. , Galeotti P. , Garbini M. , Gemme G. , Gnesi I. , Grazzi S. , Hatzifotiadou D. , La Rocca P. , Liu Z. , Lombardo L. , Mandaglio G. , Maron G. , Mazziotta M. N. , Meneghin S. , Mulliri A. , Nania R. , Noferini F. , Nozzoli F. , Palmonari F. , Panareo M. , Panetta M. P. , Paoletti R. , Parvis M. , Pellegrino C. , Perasso L. , Pinazza O. , Pinto C. , Pisano S. , Riggi F. , Righini G. , Ripoli C. , Rizzi M. , Sartorelli G. , Scapparone E. , Schioppa M. , Scioli G. , Scribano A. , Selvi M. , Serri G. , Squarcia S , Taiuti M. , Terreni G. , Torromeo G. , Travaglini R. , Trifirò A. , Trimarchi M. , Veri C. , Vistoli C. , Votano L. , Williams M. C. S. , Zichichi A. , Zuyeuski R.
Published: June 2020

The PolarquEEEst scientific programme consists in a series of measurements of the cosmic ray flux up to the highest latitudes. It started in Summer 2018, when three telescopes made out of scintillators readout by SiPMs were built and installed in Italy, Norway and on a sailboat leaving from North Island, to circumnavigate the Svalbard archipelago and land in Tromsø. They collected data on a latitude range from 44° N up to 82° N, with a dense sampling of the Northernmost interval. The PolarquEEEst mission continued afterwards with a series of measurements in Italy, Southward reaching Lampedusa, and in Germany.

In May 2019 the PolarquEEEst collaboration accomplished another important result, installing a cosmic ray observatory for the detection of secondary cosmic muons at Ny Alesund, at 79° N, made of three independent identical detectors positioned a few hundred meters from each other, and synchronized in order to operate together as a network. The configuration used will allow high precision measurements never performed before at these latitudes on a long term, also interesting for their connection with environmental phenomena. The network will also complement the existing stations for the detection of cosmic neutrons at the Svalbard archipelago, enlarging by far the physics scope that is possible to pursue in this field at this peculiar location.

Here the various missions are presented, and some preliminary results from the measurements performed are shown.
Scientific and educational aspects of the EEE Project
Authors: La Rocca P. , Abbrescia M. , Avanzini C. , Baldini L. , Baldini Ferroli R. , Batignani G. , Battaglieri M. , Boi S. , Bossini E. , Carnesecchi F. , Cicalò C. , Cifarelli L. , Coccetti F. , Coccia E. , Corvaglia A. , De Gruttola D. , De Pasquale S. , Fabbri F. , Galante L. , Galeotti P. , Garbini M. , Gemme G. , Gnesi I. , Grazzi S. , Hatzifotiadou D. , Liu Z. , Mandaglio G. , Maron G. , Mazziotta M. N. , Mulliri A. , Nania R. , Noferini F. , Nozzoli F. , Palmonari F. , Panareo M. , Panetta M. P. , Paoletti R. , Pellegrino C. , Perasso L. , Pinto C. , Piragino G. , Pisano S. , Riggi F. , Righini G. , Ripoli C. , Rizzi M. , Sartorelli G. , Scapparone E. , Schioppa M. , Scribano A. , Selvi M. , Serri G. , Squarcia S , Taiuti M. , Terreni G. , Trifirò A. , Trimarchi M. , Vistoli C. , Votano L. , Williams M. C. S. , Zichichi A. , Zuyeuski R.
Published: June 2020

The Extreme Energy Events (EEE) Project is an experiment aimed at the detection of secondary cosmic ray muons. It consists of a sparse array of about 60 telescopes, based on Multigap Resistive Plate Chambers (MRPCs), mostly distributed throughout the Italian territory, mainly in high schools locations, and at CERN. The telescopes are now operational and taking data since more than ten years with a high duty cycle and detection efficiency. The analysis activity is currently in progress and focused on several items, including the detailed study of the muon ux under dfferent conditions, its connection with atmospheric and solar events, the detection of extensive air showers and the search for long distance correlations between different extensive air showers. In this paper an overall description of the experiment will be given, together with its educational fallout. The operation of the whole array is also discussed by showing the most recent results obtained from the analysis of the collected data.
Standalone codes for simulation and reconstruction of a triple-GEM: GTS and GRAAL
Authors: Lavezzi Lia , Alexeev M. , Amoroso A. , Bagnasco S. , Baldini Ferroli R. , Balossino I. , Bertani M. , Bettoni D. , Bortone A. , Bianchi F. , Calcaterra A. , Cerioni S. , Chai J. , Cheng W. , Chiozzi S. , Cibinetto G. , Cossio F. , Cotta Ramusino A. , Cotto G. , Da Rocha Rolo M. , De Mori F. , Destefanis M. , Evangelisti F. , Farinelli R. , Fava L. , Felici G. , Gaido L. , Garzia I. , Gatta M. , Giraudo G. , Gramigna S. , Greco M. , Lusso S. , Li H. , Maggiora M. , Malaguti R. , Mangoni A. , Marcello S. , Melchiorri M. , Mezzadri G. , Mignone M. , Pacetti S. , Patteri P. , Passalacqua B. , Rivetti A. , Savrié M. , Sosio S. , Spataro S. , Tskhadadze E. , Yan L. , Wheadon R. J.
Published: June 2020

The experiment BESIII, running at the accelerator BEPCII in Beijing (P.R.C.), is going to be updated with the replacement of the Inner Drift Chamber with a Cylindrical triple-GEM Inner Tracker (CGEM-IT). In the R&D stage, two standalone C++ codes were implemented: GTS (Garfield-based Triple-GEM Simulator), for digitization and tuning of simulated data to the experimental ones, and GRAAL (GEM Reconstruction And Analysis Library), for the reconstruction and analysis of the experimental events collected in testbeams. GTS simulates the triple-GEM response to the particle passage, treating each stage separately: ionization, GEM properties, gas mixture, magnetic field and finally the induction of the signal on the anode. The necessary information was extracted by GARFIELD++ simulations, parametrized and used as input in GTS. This speeds up the simulation, since GTS performs only samplings instead of the full digitization chain. The simulated events were reconstructed with the same procedure used for experimental data and tuning factors were evaluated to obtain a satisfactory match. GRAAL is used in the analysis of the testbeam experimental data. It provides several levels of reconstruction: from the cluster formation, gathering contiguous firing strips, to the spatial position and the signal time reconstruciton. Two algorithms are used: the charge centroid and the micro-TPC, which exploit the charge deposition on the strips and the time information. Also a merging of the two algorithms is available to efficiently weight the two outcomes and obtain the best estimate of the spatial coordinate. Moreover, GRAAL performs tracking and alignment. Both codes are going to be made available also for other MPGDs simulation and reconstruction.
Investigation of Cherenkov radiation component in LYSO(Ce) crystals
Authors: Yu Barnyakov A , Yu Barnyakov M , Bobrovnikov V S , Chizhik G S , Katcin A A , Kladov V A , Ovtin I V
Published: June 2020

The fast scintillation crystals such as pure CsI or LYSO(Ce) today are considered for timing measurements in future colliding beam experiments. The aim of such counters is to determine time of particles arrival with accuracy better than 100 ps. The work is devoted to investigation of influence of Cherenkov radiation on the time resolution of the detectors based on LYSO(Ce) crystals. The results of MC simulation and beam test are presented.
Monitoring the long term stability of civil buildings through the MRPC telescopes of the EEE Project
Authors: Pinto C , Abbrescia M , Avanzini C , Baldini L , Baldini Ferroli R , Batignani G , Battaglieri M , Boi S , Bossini E , Carnesecchi F , Cicalò C , Cifarelli L , Coccetti F , Coccia E , Corvaglia A , De Gruttola D , De Pasquale S , Fabbri F , Galante L , Galeotti P , Garbini M , Gemme G , Gnesi I , Grazzi S , Hatzifotiadou D , La Rocca P , Liu Z , Mandaglio G , Maron G , Mazziotta M N , Mulliri A , Nania R , Noferini F , Nozzoli F , Palmonari F , Panareo M , Panetta M P , Paoletti R , Pellegrino C , Perasso L , Piragino G , Pisano S , Riggi F , Righini G , Ripoli C , Rizzi M , Sartorelli G , Scapparone E , Schioppa M , Scribano A , Selvi M , Serri G , Squarcia S , Taiuti M , Terreni G , Trifirò A , Trimarchi M , Vistoli C , Votano L , Williams M C S , Zichichi A , Zuyeuski R
Published: June 2020

Cosmic ray muons are a penetrating component of extensive air showers created in the Earth atmosphere by the interaction of highly energetic primary particles, mostly protons, which continuously bombard our Planet. The secondary cosmic radiation is the result of the complex interplay between the production cross section and the interaction mechanisms with the atmosphere (including the energy loss, multiple scattering and particle decay). Cosmic muons have been considered since several decades as a powerful probe to exploit our environment, from muography of volcanoes to absorption radiography of possible hidden rooms inside large structures, such as Pyramids, to the detection of high-Z illicit nuclear materials inside containers and many other applications of social interest.

This paper discusses the possibility to employ the Multigap Resistive Plate Chambers (MRPC) of the Extreme Energy Events (EEE) Project as muon tracking detectors to monitor the long term stability of civil buildings and structures when used in conjunction with additional detectors. For this application the average direction of the cosmic muon tracks passing through the MRPC telescope and an additional detector located some distance apart in the same building may be reconstructed with good precision and any small variation over long time acquisition periods may be monitored. The performance of such setup is discussed and experimental results from first coincidence measurements obtained with a 40 × 60 cm2 scintillator detector operated in the same building with one of the EEE telescopes, at about 15 m vertical distance from it, are presented. Simple Monte Carlo and GEANT simulations were also carried out to evaluate typical acceptance values for the operating conditions employed so far, to extrapolate to other geometrical configurations, and to evaluate multiple scattering effects.
Drivers of CO2 emissions in international aviation: the case of Japan
Authors: Kito Minami , Nagashima Fumiya , Kagawa Shigemi , Nansai Keisuke
Published: June 2020

We estimated the CO2 emissions produced by more than 40 000 international flights associated with Japan’s two major airlines (Japan Airlines and All Nippon Airways), and identified the drivers for these CO2 emissions using an index decomposition analysis conducted between 2005 and 2015. The results showed that introducing the more fuel-efficient Boeing 787 led to CO2 emission reductions of 1.3 million tons by the two companies. However, these reductions were canceled out by the total number of flights and distances per passenger attributable to the airlines’ operations. We conclude that the environmental and business strategy of introducing greener aircraft with better fuel efficiency was insufficient for mitigating aircraft emissions’ effects on climate.
Memory effects in fluctuating dynamic density-functional theory: theory and simulations
Authors: Russo Antonio , Durán-Olivencia Miguel A , Yatsyshin Peter , Kalliadasis Serafim
Published: June 2020

This work introduces a theoretical framework to describe the dynamics of reacting multi-species fluid systems in-and-out of equilibrium. Our starting point is the system of generalised Langevin equations which describes the evolution of the positions and momenta of the constituent particles. One particular difficulty that this system of generalised Langevin equations exhibits is the presence of a history-dependent (i.e. non-Markovian) term, which in turn makes the system’s dynamics dependent on its own past history. With the appropriate definitions of the local number density and momentum fields, we are able to derive a non-Markovian Navier–Stokes-like system of equations constituting a generalisation of the Dean–Kawasaki model. These equations, however, still depend on the full set of particles phase-space coordinates. To remove this dependence on the microscopic level without washing out the fluctuation effects characteristic of a mesoscopic description, we need to carefully ensemble-average our generalised Dean–Kawasaki equations. The outcome of such a treatment is a set of non-Markovian fluctuating hydrodynamic equations governing the time evolution of the mesoscopic density and momentum fields. Moreover, with the introduction of an energy functional which recovers the one used in classical density-functional theory and its dynamic extension (DDFT) under the local-equilibrium approximation, we derive a novel non-Markovian fluctuating DDFT (FDDFT) for reacting multi-species fluid systems. With the aim of reducing the fluctuating dynamics to a single equation for the density field, in the spirit of classical DDFT, we make use of a deconvolution operator which makes it possible to obtain the overdamped version of the non-Markovian FDDFT. A finite-volume discretization of the derived non-Markovian FDDFT is then proposed. With this, we validate our theoretical framework in-and-out-of-equilibrium by comparing results against atomistic simulations. Finally, we illustrate the influence of non-Markovian effects on the dynamics of non-linear chemically reacting fluid systems with a detailed study of memory-driven Turing patterns.