bluuebunny/crossref_metadata_2025 huggingface dataset:
A Morphing Technique Applied to Lung Motions in Radiotherapy: Preliminary Results
Authors: Laurent R. , Henriet J. , Gschwind R. , Makovicka L.
Published: March 2021

Organ motion leads to dosimetric uncertainties during a patient’s treatment. Much work has been done to quantify the dosimetric effects of lung movement during radiation treatment. There is a particular need for a good description and prediction of organ motion. To describe lung motion more precisely, we have examined the possibility of using a computer technique: a morphing algorithm. Morphing is an iterative method which consists of blending one image into another image. To evaluate the use of morphing, Four Dimensions Computed Tomography (4DCT) acquisition of a patient was performed. The lungs were automatically segmented for different phases, and morphing was performed using the end-inspiration and the end-expiration phase scans only. Intermediate morphing files were compared with 4DCT intermediate images. The results showed good agreement between morphing images and 4DCT images: fewer than 2 % of the 512 by 256 voxels were wrongly classified as belonging/not belonging to a lung section. This paper presents preliminary results, and our morphing algorithm needs improvement. We can infer that morphing offers considerable advantages in terms of radiation protection of the patient during the diagnosis phase, handling of artifacts, definition of organ contours and description of organ motion.
Welding of Aluminum Using a Pulsed Nd:YAG Laser
Authors: Nerádová M. , Kovačócy P.
Published: March 2021

This paper deals with pulsed laser welding of aluminum using an Nd:YAG laser with wavelength 1.06 μm. Technically pure aluminum (95.50 wt. %) was used as the welded material. Eighteen welds (penetration passes) were fabricated in the experiment. Optical microscopy was used to assess the influence of changes in the parameters of the pulsed laser on the quality and geometry of the penetration passes of aluminum and on the hardness measurement through the interface of the welds. The results show that the geometry of the penetration passes was influenced above all by the position of the beam focus.
Astronomical Image Compression Techniques Based on ACC and KLT Coder
Authors: Schindler J. , Páta P. , Klíma M. , Fliegel K.
Published: March 2021

This paper deals with a compression of image data in applications in astronomy. Astronomical images have typical specific properties — high grayscale bit depth, size, noise occurrence and special processing algorithms. They belong to the class of scientific images. Their processing and compression is quite different from the classical approach of multimedia image processing. The database of images from BOOTES (Burst Observer and Optical Transient Exploring System) has been chosen as a source of the testing signal. BOOTES is a Czech-Spanish robotic telescope for observing AGN (active galactic nuclei) and the optical transient of GRB (gamma ray bursts) searching. This paper discusses an approach based on an analysis of statistical properties of image data. A comparison of two irrelevancy reduction methods is presented from a scientific (astrometric and photometric) point of view. The first method is based on a statistical approach, using the Karhunen-Loeve transform (KLT) with uniform quantization in the spectral domain. The second technique is derived from wavelet decomposition with adaptive selection of used prediction coefficients. Finally, the comparison of three redundancy reduction methods is discussed. Multimedia format JPEG2000 and HCOMPRESS, designed especially for astronomical images, are compared with the new Astronomical Context Coder (ACC) coder based on adaptive median regression.
Bidifferential Calculus, Matrix SIT and Sine-Gordon Equations
Authors: Dimakis A. , Kanning N. , Müller-Hoissen F.
Published: March 2021

We express a matrix version of the self-induced transparency (SIT) equations in the bidifferential calculus framework. An infinite family of exact solutions is then obtained by application of a general result that generates exact solutions from solutions of a linear system of arbitrary matrix size. A side result is a solution formula for the sine-Gordon equation.
Current Exchanges for Reducible Higher Spin Modes on AdS
Authors: Fotopoulos A. , Tsulaia M.
Published: March 2021

We show how to decompose a Lagrangian for reducible massless bosonic Higher Spin modes into the ones describing irreducible (Fronsdal) Higher Spin modes on a D dimensional AdS space. Using this decomposition we construct a new nonabelian cubic interaction vertex for reducible higher spin modes and two scalars on AdS from the already known vertex which involves irreducible (Fronsdal) modes
The Problem of Predecessors on Spanning Trees
Authors: Poghosyan V. S. , Priezzhev V. B.
Published: March 2021

We consider the equiprobable distribution of spanning trees on the square lattice. All bonds of each tree can be oriented uniquely with respect to an arbitrary chosen site called the root. The problem of predecessors is to find the probability that a path along the oriented bonds passes sequentially fixed sites i and j. The conformal field theory for the Potts model predicts the fractal dimension of the path to be 5/4. Using this result, we show that the probability in the predecessors problem for two sites separated by large distance r decreases as P(r) ∼ r −3/4. If sites i and j are nearest neighbors on the square lattice, the probability P(1) = 5/16 can be found from the analytical theory developed for the sandpile model. The known equivalence between the loop erased random walk (LERW) and the directed path on the spanning tree states that P(1) is the probability for the LERW started at i to reach the neighboring site j. By analogy with the self-avoiding walk, P(1) can be called the return probability. Extensive Monte-Carlo simulations confirm the theoretical predictions.
Supersymmetry in the Quark-Diquark and the Baryon-Meson Systems
Authors: Catto S. , Choun Y.
Published: March 2021

A superalgebra extracted from the Jordan algebra of the 27 and 27 dim. representations of the group E6 is shown to be relevant to the description of the quark-antidiquark system. A bilocal baryon-meson field is constructed from two quark-antiquark fields. In the local approximation the hadron field is shown to exhibit supersymmetry which is then extended to hadronic mother trajectories and inclusion of multiquark states. Solving the spin-free Hamiltonian with light quark masses we develop a new kind of special function theory generalizing all existing mathematical theories of confluent hypergeometric type. The solution produces extra “hidden” quantum numbers relevant for description of supersymmetry and for generating new mass formulas.
A Taxonomy of Technical Animation
Authors: Vaněček D. , Jirsa J.
Published: March 2021

The age in which we are living nowadays is characterized by rapid innovation in the development of information and communication technologies (ICT). This innovation has a significant influence on the education process. This article deals with computer animation in technical education. Our aim is to show the taxonomy of education animation. The paper includes practical examples of animation.
Two Remarks to Bifullness of Centers of Archimedean Atomic Lattice Effect Algebras
Authors: Kalina M.
Published: March 2021

Lattice effect algebras generalize orthomodular lattices as well as MV-algebras. This means that within lattice effect algebras it is possible to model such effects as unsharpness (fuzziness) and/or non-compatibility. The main problem is the existence of a state. There are lattice effect algebras with no state. For this reason we need some conditions that simplify checking the existence of a state. If we know that the center C(E) of an atomic Archimedean lattice effect algebra E (which is again atomic) is a bifull sublattice of E, then we are able to represent E as a subdirect product of lattice effect algebras Ei where the top element of each one of Ei is an atom of C(E). In this case it is enough if we find a state at least in one of Ei and we are able to extend this state to the whole lattice effect algebra E. In [8] an atomic lattice effect algebra E (in fact, an atomic orthomodular lattice) with atomic center C(E) was constructed, where C(E) is not a bifull sublattice of E. In this paper we show that for atomic lattice effect algebras E (atomic orthomodular lattices) neither completeness (and atomicity) of C(E) nor σ-completeness of E are sufficient conditions for C(E) to be a bifull sublattice of E.
A Pitch Detection Algorithm for Continuous Speech Signals Using Viterbi Traceback with Temporal Forgetting
Authors: Bartošek J.
Published: March 2021

This paper presents a pitch-detection algorithm (PDA) for application to signals containing continuous speech. The core of the method is based on merged normalized forward-backward correlation (MNFBC) working in the time domain with the ability to make basic voicing decisions. In addition, the Viterbi traceback procedure is used for post-processing the MNFBC output considering the three best fundamental frequency (F0) candidates in each step. This should make the final pitch contour smoother, and should also prevent octave errors. In transition probabilities computation between F0 candidates, two major improvements were made over existing post-processing methods. Firstly, we compare pitch distance in musical cent units. Secondly, temporal forgetting is applied in order to avoid penalizing pitch jumps after prosodic pauses of one speaker or changes in pitch connected with turn-taking in dialogs. Results computed on a pitchreference database definitely show the benefit of the first improvement, but they have not yet proved any benefits of temporal modification. We assume this only happened due to the nature of the reference corpus, which had a small amount of suprasegmental content.
Boron Doped Nanocrystalline Diamond Films for Biosensing Applications
Authors: Petrák V. , Krucký J. , Vlčková M.
Published: March 2021

With the rise of antibiotic resistance of pathogenic bacteria there is an increased demand for monitoring the functionality of bacteria membranes, the disruption of which can be induced by peptide-lipid interactions. In this work we attempt to construct and disrupt supported lipid membranes (SLB) on boron doped nanocrystalline diamond (B-NCD). Electrochemical Impedance Spectroscopy (EIS) was used to study in situ changes related to lipid membrane formation and disruption by peptide-induced interactions. The observed impedance changes were minimal for oxidized B-NCD samples, but were still detectable in the low frequency part of the spectra. The sensitivity for the detection of membrane formation and disruption was significantly higher for hydrogenated B-NCD surfaces. Data modeling indicates large changes in the electrical charge when an electrical double layer is formed at the B-NCD/SLB interface, governed by ion absorption. By contrast, for oxidized B-NCD surfaces, these changes are negligible indicating little or no change in the surface band bending profile.
Optical Detection of Charged Biomolecules: Towards Novel Drug Delivery Systems
Authors: Petráková V.
Published: March 2021

This paper presents work done on developing optically-traceable intracellular nanodiamond sensors, where the photoluminescence can be changed by a biomolecular attachment/delivery event. Their high biocompatibility, small size and stable luminescence from their color centers make nanodiamond (ND) particles an attractive alternative to molecular dyes for drug-delivery and cell-imaging applications. In our work, we study how surface modification of ND can change the color of ND luminescence (PL). This method can be used as a novel detection tool for remote monitoring of chemical processes in biological systems. Recently, we showed that PL can be driven by atomic functionalization, leading to a change in the color of ND luminescence from red (oxidized ND) to orange (hydrogenated ND). In this work, we show how PL of ND changes similarly when interacting with positively and negatively charged molecules. The effect is demonstrated on fluorinated ND, where the high dipole moment of the C-F bond is favorable for the formation of non-covalent bonds with charged molecules. We model this effect using electrical potential changes at the diamond surface. The final aim of the work is to develop a “smart” optically traceable drug carrier, where the delivery event is optically detectable.
Impacts of New EU and Czech Environmental Legislation on Heat and Electricity Prices of Combined Heat and Power Sources in the Czech Republic
Authors: Vecka J.
Published: March 2021

In my economic model I calculate the impact of the new EU ETS Directive, the Industrial Emissions Directive and the new air protection law on future heat and electricity prices for combined heat and power sources. I discover that there will be a significant increase in heat and electricity prices, especially because of the implementation of new so-called benchmark tools for allocating allowances. The main problem of large heat producers in this respect is loss of competitiveness on the heat market due to emerging stricter environmental legislation, which is not applied to competitors on the heat market (smaller heat sources). There is also lack of clarity about the modalities for allocating free allowances, and about the future development of the whole carbon market (the future European allowance price).
Czech Contribution to Athena
Authors: Hudec R. , Pína L. , Maršíková V. , Inneman A. , Skulinová M. , Míka M.
Published: March 2021

We describe the recent status of the Czech contribution to the ESA Athena space mission, with emphasis on the development of new technologies and test samples of X-ray mirrors with precise surfaces, based on new materials, and their applications in space. In addition, alternative X-ray optical arrangements are investigated, such as Kirkpatrick-Baez systems.
The Intriguing Nature of the Cataclysmic Variable SS Cygni
Authors: Giovannelli F. , Sabau-Graziati L.
Published: March 2021

The classification of SS Cyg as a dwarf nova (DN), a subclass of the non–magnetic (NM) cataclysmic variable (CV) has been considered by most of the community as well established because of a paper appeared in Nature (Bath & van Paradijs, 1983), which was a bandwagon for all the papers discussing SS Cyg behaviour both from experimental and theoretical points of view. This classification has been widely accepted until nowadays, in spite of the many arguments and circumstantial proofs about its possible intermediate polar nature, as claimed by Franco Giovannelli’s group for more than 25 years.The goal of this paper is to present an objective discussion of the problems connected with the controversial nature of SS Cyg, using all the different interpretations of its multifrequency data in order to demonstrate beyond doubt its intermediate polar nature.
GRB Duration Distribution Considering the Position of the Fermi
Authors: Szécsi D. , Bagoly Z. , Horváth I. , Balázs L. G. , Veres P. , Mészáros A.
Published: March 2021

The Fermi satellite has a particular motion during its flight which enables it to catch the gamma-ray bursts mostly well. The side-effect of this favourable feature is that the lightcurves of the GBM detectors are stressed by rapidly and extremely varying background. Before this data is processed, it needs to be separated from the background. The commonly used methods [3,7] were useless for most cases of Fermi, so we developed a new technique based on the motion and orientation of the satellite. The background-free lightcurve can be used to perform statistical surveys, hence we showed the efficiency of our background-filtering method presenting a statistical analysis known from the literature.
Production of Biodiesel from Vegetable Oil Using Microware Irradiation
Authors: Kapilan N.
Published: March 2021

The petroleum oil supply crisis, the increase in demand and the price eruption have led to a search for an alternative fuel of bio-origin in India. Among the alternative fuels, biodiesel is considered as a sustainable renewable alternative fuel to fossil diesel. Non-edible jatropha oil has considerable potential for the production of biodiesel in India. The production of biodiesel from jatropha oil using a conventional heating method takes more than 1h. In this work, microwave irradiation has been used as a source of heat for the transesterification reaction. A domestic microwave oven was modified and used for microwave heating of the reactants. The time taken for biodiesel production using microwave irradiation was 1 min. The fuel property analysis shows that the properties of jatropha oil biodiesel satisfy the biodiesel standards, and are close to the fossil diesel standards. From this work, it is concluded that biodiesel can be produced from vegetable oil using microwave irradiation, with a significant reduction in production time.
Prediction of Lower Extremity Movement by Cyclograms
Authors: Kutilek P. , Viteckova S.
Published: March 2021

Human gait is nowadays undergoing extensive analysis. Predictions of leg movements can be used for orthosis and prosthesis programming, and also for rehabilitation. Our work focuses on predicting human gait with the use of angle-angle diagrams, also called cyclograms. In conjunction with artificial intelligence, cyclograms offer a wide area of medical applications. We have identified cyclogram characteristics such as the slope and the area of the cyclogram for a neural network learning algorithm. Neural networks learned by cyclograms offer wide applications in prosthesis control systems.
Optimization of Fuzzy Logic Controller for Supervisory Power System Stabilizers
Authors: Al-Turki Y. A. , Attia A.-F. , Soliman H. F.
Published: March 2021

This paper presents a powerful supervisory power system stabilizer (PSS) using an adaptive fuzzy logic controller driven by an adaptive fuzzy set (AFS). The system under study consists of two synchronous generators, each fitted with a PSS, which are connected via double transmission lines. Different types of PSS-controller techniques are considered. The proposed genetic adaptive fuzzy logic controller (GAFLC)-PSS, using 25 rules, is compared with a static fuzzy logic controller (SFLC) driven by a fixed fuzzy set (FFS) which has 49 rules. Both fuzzy logic controller (FLC) algorithms utilize the speed error and its rate of change as an input vector. The adaptive FLC algorithm uses a genetic algorithmto tune the parameters of the fuzzy set of each PSS. The FLC’s are simulated and tested when the system is subjected to different disturbances under a wide range of operating points. The proposed GAFLC using AFS reduced the computational time of the FLC, where the number of rules is reduced from 49 to 25 rules. In addition, the proposed adaptive FLC driven by a genetic algorithm also reduced the complexity of the fuzzy model, while achieving a good dynamic response of the system under study.
Modeling of Concrete Creep Based on Microprestress-solidification Theory
Authors: Havlásek P. , Jirásek M.
Published: March 2021

Creep of concrete is strongly affected by the evolution of pore humidity and temperature, which in turn depend on the environmental conditions and on the size and shape of the concrete member. Current codes of practice take that into account only approximately, in a very simplified way. A more realistic description can be achieved by advanced models, such as model B3 and its improved version that uses the concept of microprestress. The value of microprestress is influenced by the evolution of pore humidity and temperature. In this paper, values of parameters used by the microprestress-solidification theory (MPS) are recommended and their influence on the creep compliance function is evaluated and checked against experimental data from the literature. Certain deficiencies of MPS are pointed out, anda modified version of MPS is proposed.
Optimal Combustion Conditions for a Small-scale Biomass Boiler
Authors: Plaček Viktor , Oswald Cyril , Hrdlička Jan
Published: March 2021

This paper reports on an attempt to achieve maximum efficiency and lowest possible emissions for a small-scale biomass boiler. This aim can be attained only by changing the control algorithm of the boiler, and in this way not raising the acquisition costs for the boiler. This paper describes the experimental facility, the problems that arose while establishing the facility, and how we have dealt with them. The focus is on discontinuities arising after periodic grate sweeping, and on finding the parameters of the PID control loops. Alongside these methods, which need a lambda probe signal for proper functionality, we inroduce another method, which is able to intercept the optimal combustion working point without the need to use a lambda sensor.
The Effect of Temperature on the Gasification Process
Authors: Baláš Marek , Lisý Martin , Štelcl Ota
Published: March 2021

Gasification is a technology that uses fuel to produce power and heat. This technology is also suitable for biomass conversion. Biomass is a renewable energy source that is being developed to diversify the energy mix, so that the Czech Republic can reduce its dependence on fossil fuels and on raw materials for energy imported from abroad. During gasification, biomass is converted into a gas that can then be burned in a gas burner, with all the advantages of gas combustion. Alternatively, it can be used in internal combustion engines. The main task during gasification is to achieve maximum purity and maximum calorific value of the gas. The main factors are the type of gasifier, the gasification medium, biomass quality and, last but not least, the gasification mode itself. This paper describes experiments that investigate the effect of temperature and pressure on gas composition and low calorific value. The experiments were performed in an atmospheric gasifier in the laboratories of the Energy Institute atthe Faculty of Mechanical Engineering, Brno University of Technology.
Strontium As a Structure Modifier for Non-binary Al–Si Alloy
Authors: Stunová Barbora Bryksí
Published: March 2021

This paper presents a study of the influence on the structure of AlSi10Mg alloy when 400 ppm of strontium is added. Not only changes in the morphology of eutectic silicon, but in particular changes in the morphology of the intermetallicphases are monitored, namely phases containing iron and magnesium. The effect of strontium on structural defects,namely cavities formation, is also observed. It was found, that in non-binary system Al–Si–Mg also intermetallic phases of magnesium are affected by addition of strontium: especially phase Mg2Si changes the morphology significantly fromunmodified to modified structure. Moreover, findings of other authors, that strontium has a negative effect on the levelof gas porosity and on the distribution of shrinkages, are also confirmed.
A Pulverized Coal-Fired Boiler Optimized for Oxyfuel Combustion Technology
Authors: Dlouhý Tomáš , Dupal Tomáš , Dlouhý Jan
Published: March 2021

This paper presents the results of a study on modifying a pulverized coal-fired steam boiler in a 250 MWe power plant for oxygen combustion conditions. The entry point of the study is a boiler that was designed for standard air combustion. It has been proven that simply substituting air by oxygen as an oxidizer is not sufficient for maintaining a satisfactory operating mode, not even with flue gas recycling. Boiler design optimization aggregating modifications to the boiler’s dimensions, heating surfaces and recycled flue gas flow rate, and specification of a flue gas recycling extraction point is therefore necessary in order to achieve suitable conditions for oxygen combustion. Attention is given to reducing boiler leakage, to which external pre-combustion coal drying makes a major contribution. The optimization is carried out with regard to an overall power plant conception for which a decrease in efficiency due to CO2 separation is formulated.
Lifetime Assessment of a Steam Pipeline
Authors: Janovec Jiří , Poláchová Daniela , Junek Michal
Published: March 2021

The aim of this paper is to design a method for assessing the life of steam pipes for Czech power plants. The most widely-used material in Czech power plants is steel 15 128. Our findings may also be applied for international equivalents of this steel. The paper shows the classification of cavitation damage and microstructure classification status, based on the German VGB Act, with references to EPRI law in the USA. Calculations of remaining life on the basis of Russian experience are also shown. The possibility of applying this method to increase the operating parameters for power plants is discussed.
Advanced Functions of a Modern Power Source for GMAW Welding of Steel
Authors: Kolařík Ladislav , Kolaříková Marie , Kovanda Karel , Pantůček Marek , Vondrouš Petr
Published: March 2021

This paper evaluates the use of a modern welding power source equipped with advanced arc control functions. At the Laboratory of Welding Technologies of CTU in Prague we have focused on GMAW welding of steel using Sigma Galaxy, a modern welding power source produced by Migatronic. Sigma Galaxy is equipped with functions called Intelligent Arc Control and Sequence Repeat. According to the manufacturer, controlling an arc by these functions should significantly stabilize the welding process, lower the heat input and the deformation, and improve the weld quality. To evaluate the benefits of these functions completely, single V butt welds were performed on S275J2 structural steel 10 mm in thickness (2 weld layers: root+capping layer) in PF and PG positions. Welding was monitored by the Welding Information System, and was compared with standard GMAW welding. The results have shown that these “intelligent” functions offer significant advantages for steel welding, especially in vertical and overhead positions, because they lower the heat input and improve the weld metal control.
Fundamental Research on Hydraulic Systems Driven by Alternating Flow
Authors: Marcu Ioan-Lucian , Banyai Daniel-Vasile
Published: March 2021

This paper presents a new approach to rotary hydraulic systems, and the functional principles of rotary hydraulic systems that can work using alternating flows. Hydraulic transmissions using alternating flows are based on bidirectional displacement of a predefined volume of fluid through the connection pipes between the alternating flow, the pressure energy generator and the motor. The paper also presents some considerations regarding the basic calculation formulas, the design and testing principles for a hydraulic motor driven by alternating flow, and also a three-phase rotary hydraulic motor.
Hygiena 3, a Forgotten Project for Electrolytic Water Treatment
Authors: Drnek Kryštof
Published: March 2021

In the interwar period, the city of Prague had to resolve the problem of treating the polluted water produced by its citizens. From 1933 - 1936 an ambitious competition was held. The idea behind the competition was to bring in new ideas and projects for a new water treatment station.Hygiena 3 was one of the projects that was submitted. It proposed a treatment procedure based on electrolytic consolidation of contaminants in water into flocks. The project was found to be inventive and interesting but too expensive and not effective. Nevertheless it was evaluated as a well developed proposal and received an award from the city.
A Study of Parameters Setting of the STADZT
Authors: Turoň Václav
Published: March 2021

This paper deals with the new time-frequency Short-Time Approximated Discrete Zolotarev Transform (STADZT), which is based on symmetrical Zolotarev polynomials. Due to the special properties of these polynomials, STADZT can be used for spectral analysis of stationary and non-stationary signals with the better time and frequency resolution than the widely used Short-Time Fourier Transform (STFT). This paper describes the parameters of STADZT that have the main influence on its properties and behaviour. The selected parameters include the shape and length of the segmentation window, and the segmentation overlap. Because STADZT is very similar to STFT, the paper includes a comparison of the spectral analysis of a non-stationary signal created by STADZT and by STFT with various settings of the parameters.
Research Trends for PID Controllers
Authors: Visioli Antonio
Published: March 2021

This paper analyses the most significant issues that have been recently been addressed by researchers in the field of Proportional-Integral-Derivative (PID) controllers. In particular, the most recent techniques proposed for tuning and designing PID-based control structures are briefly reviewed, together with methods for assessing their performance. Finally, fractional-order and event-based PID controllers are presented among the most significant developments in the field.
Evaluation of Bioelectrical Impedance Spectroscopy for the Assessment of Extracellular Body Water
Authors: Weyer Sören , Röthlingshöfer Lisa , Walter Marian , Leonhardt Steffen
Published: March 2021

This study evaluates bioelectrical impedance spectroscopy (BIS) measurements to detect body fluid status. The multifrequency impedance measurements were performed in five female pigs. Animals were connected to an extracorporeal membrane oxygenation device during a lung disease experiment and fluid balance was recorded. Every 15 min the amount of fluid infusion and the weight of the urine drainage bag was recorded. From the fluid intake and output, the fluid balance was calculated. These data were compared with values calculated from a mathematical model, based on the extracellular tissue resistance and the Hanai Mixture theory. The extracellular tissue resistance was also measured with BIS. These experimental results strongly support the feasibility and clinical value of BIS for in vivo assessment of the hydration status.
Micromechanical Analysis of Cement Paste with Carbon Nanotubes
Authors: Šmilauer Vít , Hlaváček Petr , Padevět Pavel
Published: March 2021

Carbon nanotubes (CNT) are an attractive reinforcement material for several composites, due to their inherently high strength and high modulus of elasticity. There are controversial results for cement paste with admixed CNT up to 500 µm in length. Some results show an increase in flexural or compressive strength, while others showing a decrease in the values. Our experiments produced results that showed a small increase in fracture energy and tensile strength. Micromechanical simulations on a CNT-reinforced cement paste 50×50 µm proved that CNT clustering is the crucial factor for an increasein fracture energy and for an improvement in tensile strength.
Massive Parallelization of Multibody System Simulation
Authors: Valášek Michael , Mráz Ladislav
Published: March 2021

This paper deals with the decrease in CPU time necessary for simulating multibody systems by massive parallelization. The direct dynamics of multibody systems has to be solved by a system of linear algebraic equations. This is a bottleneck for the efficient usage of multiple processors. Simultaneous solution of this task means that the excitation is immediately spread into all components of the multibody system. The bottleneck can be avoided by introducing additional dynamics, and this leads to the possibility of massive parallelization. Two approaches are described. One is a heterogeneousmultiscale method, and the other involves solving a system of linear algebraic equations by artificial dynamics.
Simulation of Free Airfoil Vibrations in Incompressible Viscous Flow — Comparison of FEM and FVM
Authors: Sváček Petr , Horáček Jaromír , Honzátko Radek , Kozel Karel
Published: March 2021

This paper deals with a numerical solution of the interaction of two-dimensional (2-D) incompressible viscous flow and a vibrating profile NACA 0012 with large amplitudes. The laminar flow is described by the Navier-Stokes equations in the arbitrary Lagrangian-Eulerian form. The profile with two degrees of freedom (2-DOF) can rotate around its elastic axis and oscillate in the vertical direction. Its motion is described by a nonlinear system of two ordinary differential equations. Deformations of the computational domain due to the profile motion are treated by the arbitrary Lagrangian-Eulerianmethod. The finite volume method and the finite element method are applied, and the numerical results are compared.
DISCOURSE ON OPTIMIZING THE CULTURAL HERITAGE OF BUNG KARNO SCHOOLS IN MOJOKERTO CITY FOR SOCIAL AND ECONOMIC WELFARE
Authors: Rachman Rio Febriannur
Published: March 2021

In 2019, the City Government of Mojokerto declared two schools, SDN Purwotengah and SMPN 2 Kota Mojokerto as cultural heritage. Soekarno also known as Bung Karno, one of the founding fathers of this country, Indonesia, studied there, on 1908 until 1916. This study discusses how the discourse on optimizing the cultural heritage of Bung Karno's two schools as historical tourism objects, from the perspective of social and economic welfare of the community. The theory used in this study is public policy, popularized by Thomas Dye and James E. Anderson. This study uses a qualitative method with the discourse analysis approach of Norman Fairclough. The discourse analyzed anything was conveyed by the Mayor of Mojokerto Ika Puspitasari and the Head of the Education Office Amin Wachid in the Srawung program, which aired from 16.00 to 17.00, 18 August 2020, on TVRI East Java. The result of this study indicates, the City Government of Mojokerto is serious, regarding make historical tourism objects in the cultural heritage buildings of the Bung Karno Schools. The City Government of Mojokerto considers, it will further foster a sense of community nationalism, provide authentic historical insights, as well as emerge a populist economy.keywords: Cultural Heritage, Discourse, Public Policy, Social and Economic Welfare
MENDORONG PERTUMBUHAN EKONOMI MELALUI PENINGKATAN PARTISIPASI SOSIAL: Studi Kasus Pembangunan Ekowisata di Desa Mandak
Authors: Mubarok Akhmad Munif , Barata Lukman Wijaya , Sundari Siti
Published: March 2021

This article explores public awareness in shaping ecotourism in Mandak Village. Participation through the development of Watu Rumpuk Tourism in Mendak Village, Perdagangan District, Madiun Regency is one of the uses of social participation in an effort to encourage the economic growth of the Mendak Village community. This research approach is qualitative and type of research uses descriptive studies. Determination of informants in research using purposive techniques. Data collection techniques are observation, interviews, and documentation. Data analysis uses data reduction, data presentation, and drawing conclusions and verification. The data validity technique uses source triangulation. The results showed that participation formed by the Mendak Village community was a form of horizontal participation. Where horizontal participation is participation born from community self-awareness in dealing with existing problems. The background of the formation of this participation comes from the condition of clove harvest failure which is a common problem. Then the problem solving is obtained by exploiting natural potential, namely tourism development. Development activities are carried out in mutual cooperation until there is economic growth, all these activities are a form of development carried out by community participation. The participation in Watu Rusun tourism development can occur because of the willingness of the community to be involved in tourism development, the opportunities provided by the community, and the ability of the community to utilize tourism. The benefits of participation in tourism development for the community are the availability of new jobs, the emergence of businesses in processing local potential, and the existence of CSR from investors for tourism development.Keywords: Failure of Clove Agriculture, Social Participation, Watu Rusun Tourism Development, community economic growth.
Using cluster edge counting to aggregate iterations of centroid-linkage clustering results and avoid large distance matrices
Authors: Kellom Matthew , Raymond Jason
Published: March 2021

Sequence clustering is a fundamental tool of molecular biology that is being challenged by increasing dataset sizes from high-throughput sequencing. The agglomerative algorithms that have been relied upon for their accuracy require the construction of computationally costly distance matrices which can overwhelm basic research personal computers. Alternative algorithms exist, such as centroid-linkage, to circumvent large memory requirements but their results are often input-order dependent. We present a method for bootstrapping the results of many centroid-linkage clustering iterations into an aggregate set of clusters, increasing cluster accuracy without a distance matrix. This method ranks cluster edges by conservation across iterations and reconstructs aggregate clusters from the resulting ranked edge list, pruning out low-frequency cluster edges that may have been a result of a specific sequence input order. Aggregating centroid-linkage clustering iterations can help researchers using basic research personal computers acquire more reliable clustering results without increasing memory resources.
Development and validation of an allele-specific PCR assay for genotyping a promoter and exonic single nucleotide polymorphisms of MGMT gene
Authors: Tyagi Anuj Kumar , Khoshbeen Mary Boudal , Curtis Patricia Huezo-Diaz , S. Uppugunduri Chakradhara Rao , Ansari Marc
Published: March 2021

DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) specifically remove the methyl/alkyl group from the O6-position of guanine and restore the guanine to its normal form without causing DNA strand breaks. Relationship between MGMT activity and resistance to alkylating therapeutic agents is well established. Non-availability of simple, cost-effective and efficient methods of genotyping may hinder investigations on genotype-phenotype associations. No simple genotyping procedures such as allele-discrimination Taqman Assays were available for two genetic variations in MGMT gene that had previously demonstrated to be affecting its function and expression.These two variants were included to genotype in a clinical study (Clinicaltrail.gov ID: NCT01257854). Hence, the present study is aimed at developing,   validating a rapid and simple allele-specific PCR method that genotypes exonic variant rs2308321 (c.520A>G) and a promoter variant rs113813075 (c.-459C>A) with standard PCR instruments.Web-based allele-specific (AS) primer design application called web-based allele-specific primer was used to design primers. Genomic DNA of lymphoblastoid cell line obtained from the Coriell repository with known genotypes were used to standardize the genotyping procedure. The PCR products were analyzed by 3% Agarose gel electrophoresis and by DNA Screen Tape assay with the Agilent 4200 TapeStation. The allele-specific PCR assay described here is a suitable strategy for efficient and reliable genotyping for difficult variants. This method offers cost-effective strategy for genotyping in clinical cohort studies provided positive controls established by Sanger sequencing are available for the variant. 
High-yield purification of exceptional-quality, single-molecule DNA substrates
Authors: Lu Yue , Bianco Piero
Published: March 2021

Single-molecule studies involving DNA or RNA, require homogeneous preparations of nucleic acid substrates of exceptional quality. Over the past several years, a variety of methods have been published describing different purification methods but these are frustratingly inconsistent with variable yields even in the hands of experienced bench scientists. To address these issues, we present an optimized and straightforward, column-based approach that is reproducible and produces high yields of substrates or substrate components of exceptional quality. Central to the success of the method presented is the use of a non-porous anion exchange resin. In addition to the use of this resin, we encourage the optimization of each step in the construction of substrates. The fully optimized method produces high yields of a hairpin DNA substrate of exceptional quality. While this substrate is suitable for single-molecule, magnetic tweezer experiments, the described method is readily adaptable to the production of DNA substrates for the majority of single-molecule studies involving nucleic acids ranging in size from 70–15000 bp.
Mathematics and Cosmology in Plato’s Timaeus
Authors: Gregory Andrew
Published: March 2021

Plato used mathematics extensively in his account of the cosmos in the Timaeus, but as he did not use equations, but did use geometry, harmony and according to some, numerology, it has not been clear how or to what effect he used mathematics. This paper argues that the relationship between mathematics and cosmology is not atemporally evident and that Plato’s use of mathematics was an open and rational possibility in his context, though that sort of use of mathematics has subsequently been superseded as science has progressed. I argue that there is a philosophically and historically meaningful space between ‘primitive’ or unreflective uses of mathematics and the modern conception of how mathematics relates to cosmology. Plato’s use of mathematics in the Timaeus enabled the cosmos to be as good as it could be, allowed the demiurge a rational choice (of which planetary orbits and which atomic shapes to instantiate) and allowed Timaeus to give an account of the cosmos (where if the demiurge did not have such a rational choice he would not have been able to do so). I also argue that within this space it is both meaningful and important to differentiate between Pythagorean and Platonic uses of number and that we need to reject the idea of ‘Pythagorean/Platonic number mysticism’. Plato’s use of number in the Timaeus was not mystical even though it does not match modern usage.
Why Trump Became a ‘Confederate’ President
Authors: Maxwell Angie
Published: March 2021

This article explores the causes for and the contemporary ramifications of the realignment of the American South with the Republican Party. Using the American National Election Surveys (ANES) Time Series Cumulative Data File (1948–2016), the 2016 and 2020 Blair Center Polls, and the election tracking data compiled by Richard Berg-Andersson and Tony Roza atwww.thegreenpapers.com, the author first explores the role that racial animus, anti-feminism, and religious fundamentalism played in white southern voters’ emergence as the Republican Party base. Second, the author considers the structural advantages that this prominence in the GOP gives southern whites in the primary nomination process and to what degree these advantages benefitted Donald Trump in 2016. Finally, the author explores the influence of Racial Resentment, Modern Sexism, and Christian Fundamentalism on the 2016 Republican primary elections and the 2016 and 2020 General Elections.
Háblame de tí: Latino mobilization, group dynamics and issue prioritization in the 2020 Election
Authors: Ocampo Angela X. , Garcia-Rios Sergio I. , Gutierrez Angela E.
Published: March 2021

What motivated Latinos to turnout in 2020 in the middle of a global health pandemic that has devastated their community financially, physically and mentally? How might we explain Latino support for each one of the Presidential candidates in the context of these crises? In this paper, we tackle these questions through an investigation of the factors that drove Latino turnout in 2020 and what might explain Latino favorability for Joe Biden and Donald Trump. To contextualize these findings, we compare these results to the 2016 election. We find that the most predictive factors of Latino turnout in 2020 were perceived group discrimination and mobilization efforts by campaigns and other organizations. We also find that Latino candidate preference in 2020 can be best explained by issue prioritization. Latinos for whom the economy was the most important issue were more likely to support Donald Trump. However, Latinos for whom COVID-19 and racism towards the Latino community were the top pressing political priorities were more likely to favor Joe Biden. These findings continue to shed light on the diversity and heterogeneity of the Latino vote and speak to the significance of outreach efforts by political parties, candidates and community organizations.
Microstructure and polarization behavior of Ni/WC+GO (graphene oxide) composite cladding fusion coating
Authors: Li Ouyang , Yang Guirong , Song Wenming , Gao Dawen , Sun Xianming
Published: March 2021

Ni/WC/graphene oxide (GO) composite cladding fusion coatings were fabricated through the vacuum cladding technique on a medium carbon structure steel (45# steel) substrate whose carbon content was 0.45 ± 0.03%. The microstructural characteristics, phase composition, and electrochemical polarization characteristics of the composite cladding fusion coatings were analyzed with scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and the electrochemical workstation CHI660E. Results show that the microstructure was compact and was micro-crack free, and without inclusions or other defects. It was comprised of four micro-zones, namely, the composite, transition, diffusion fusion, and diffusion-affected zones with thicknesses of approximately 4 mm, 1 mm, 20 μm, and 250 μm, respectively. The main phases of the composite coating were γ-Ni solid solution, WC, Cr7C3, Ni2.9Cr0.7Fe0.36, Cr23C6, Ni3Fe, Ni3Si, Ni3B, W2C, and C. The self-corrosion potential of the composite coatings had increased by 0.3269 V compared with that of the substrate, and the corrosion current density of the composite coatings had decreased by nearly two orders of magnitude. The Ni-based solid solution region with relatively high C and Cr contents was difficult to dissolve.
Effects of microstructure and lattice misfit on creep life of Ni-based single crystal superalloy during long-term thermal exposure
Authors: Gan Wenyan , Gao Hangshan , Pei Haiqing , Wen Zhixun
Published: March 2021

According to the microstructural evolution during longterm thermal exposure at 1100°C, the creep rupture life of Ni-based single crystal superalloys at 980°C/270 MPa was evaluated. The microstructure was characterized by means of scanning electron microscopy, X-ray diffraction and related image processing methods. The size of γ’precipitates and the precipitation amount of topologically close-packed increased with the increase in thermal exposure time, and coarsening of the γ’precipitates led to the simultaneous increase of the matrix channel width. The relationship between the creep rupture life and the lattice misfit of γ/γ’, the coarsening of γ’precipitate and the precipitation of TCP phase are systematically discussed. In addition, according to the correlation between γ’phase evolution and creep characteristics during thermal exposure, a physical model is established to predict the remaining creep life.
Microstructure, phase relationships and microhardness of Fe60Al40–n
Hf
n
alloys (n = 1, 3, and 5 at.%)
Authors: Yildirim Mehmet , Çetinbakış Neşe , Culu Ayşe , Vedat Akdeniz M. , Mekhrabov Amdulla O.
Published: March 2021

The microstructural evolution, solidification behavior, phase relationships, microhardness and room temperature magnetic properties of the hypoeutectic Fe60Al40-n
Hf
n
(n = 1, 3, and 5 at.%) compositions are investigated in detail. The micro-structure of the studied alloys is composed of Fe–Al based dendrites and eutectic mixture. The components of the eutectic are B2 Fe–Al based and HfFe6Al6 τ1 phases. With increasing Hf fraction, the amounts of eutectic and τ1 phases increase continuously which results in significant strengthening. Based on the differential scanning calorimetry results, the eutectic reaction temperature is measured as 1251 °C. Fe60Al40-n
Hf
n
alloys show weak room temperature ferromagnetism and their magnetization values also increase with increasing Hf content.