bluuebunny/crossref_metadata_2025 huggingface dataset:
A path integral ground state replica trick approach for the computation of entanglement entropy of dipolar linear rotors
Authors: Sahoo Tapas , Iouchtchenko Dmitri , Herdman C. M. , Roy Pierre-Nicholas
Published: May 2020

We calculate the second Rényi entanglement entropy for systems of interacting linear rotors in their ground state as a measure of entanglement for continuous rotational degrees of freedom. The entropy is defined in relation to the purity of a subsystem in a bipartite quantum system, and to compute it, we compare two sampling ensembles based on the path integral ground state (PIGS) formalism. This scheme centers on the replica trick and is aided by the ratio trick, both developed in this context by Hastings et al. [Phys. Rev. Lett. 104, 157201 (2010)]. We study a system composed of linear quantum rotors on a lattice in one dimension, interacting via an anisotropic dipole–dipole potential. The ground state second Rényi entropies estimated by PIGS are benchmarked against those from the density matrix renormalization group for various interaction strengths and system sizes. We find that the entropy grows with an increase in interaction strength, and for large enough systems, it appears to plateau near log(2). We posit that the limiting case of many strongly interacting rotors behaves akin to a lattice of two-level particles in a cat state, in which one naturally finds an entanglement entropy of log(2).
Dielectric loss extraction for superconducting microwave resonators
Authors: McRae C. R. H. , Lake R. E. , Long J. L. , Bal M. , Wu X. , Jugdersuren B. , Metcalf T. H. , Liu X. , Pappas D. P.
Published: May 2020

The investigation of two-level-state (TLS) loss in dielectric materials and interfaces remains at the forefront of materials research in superconducting quantum circuits. We demonstrate a method of TLS loss extraction of a thin film dielectric by using a lumped element resonator fabricated from a superconductor-dielectric-superconductor trilayer. We extract the dielectric loss by formulating a circuit model for a lumped element resonator with TLS loss and then fitting to this model using measurements from a set of three resonator designs: a coplanar waveguide resonator, a lumped element resonator with an interdigitated capacitor, and a lumped element resonator with a parallel plate capacitor that includes the dielectric thin film of interest. Unlike the commonly used single measurement technique, this method allows the accurate measurement of materials with TLS loss lower than 10−6. We demonstrate this method by extracting a TLS loss of 1.00×10−3 for sputtered Al2O3 using a set of samples fabricated from an Al/Al2O3/Al trilayer. We compare this method with the single measurement technique and observe a difference of 11% in extracted loss of the trilayer.
Abrupt enhancement of spin–orbit scattering time in ultrathin semimetallic SrIrO3 close to the metal–insulator transition
Authors: Zhang L. , Jiang X. , Xu X. , Hong X.
Published: May 2020

We report a magnetotransport study of spin relaxation in 1.4–21.2 nm epitaxial SrIrO3 thin films coherently strained on SrTiO3 substrates. Fully charge compensated semimetallic transport has been observed in SrIrO3 films thicker than 1.6 nm, where the charge mobility at 10 K increases from 45 cm2/V s to 150 cm2/V s with decreasing film thickness. In the two-dimensional regime, the charge dephasing and spin–orbit scattering lengths extracted from the weak localization/anti-localization effects show power-law dependence on temperature, pointing to the important role of electron–electron interaction. The spin–orbit scattering time τso exhibits an Elliott–Yafet mechanism dominated quasi-linear dependence on the momentum relaxation time τp. Ultrathin films approaching the critical thickness of metal–insulator transition show an abrupt enhancement in τso, with the corresponding τso/τp about 7.6 times of the value for thicker films. A likely origin for such unusual enhancement is the onset of strong electron correlation, which leads to charge gap formation and suppresses spin scattering.
Helical structures with switchable and hierarchical chirality
Authors: Feng Huijuan , Lv Weilin , Ma Jiayao , Chang Wenwu , Chen Yan , Wang Jianshan
Published: May 2020

Chirality is present as a trend of research in biological and chemical communities for it has a significant effect on physiological properties and pharmacological effects. Further, manipulating specific morphological chirality recently has emerged as a promising approach to design metamaterials with tailored mechanical, optical, or electromagnetic properties. However, the realization of many properties found in nature, such as switchable and hierarchical chirality, which allows electromagnetic control of the polarization of light and enhancement of mechanical properties, in man-made structures has remained a challenge. Here, we present helical structures with switchable and hierarchical chirality inspired by origami techniques. We propose eggbox-based chiral units for constructing homogeneous and heterogeneous chiral structures and demonstrate a theoretical approach for tuning the chirality of these structures by modulating their geometrical parameters and for achieving chirality switching through mechanism bifurcation. Finally, by introducing a helical tessellation between the chiral units, we design hierarchical structures with chirality transferring from construction elements to the morphological level and discover a helix with two zero-height configurations during the unwinding process. We anticipate that our design and analysis approach could facilitate the development of man-made metamaterials with chiral features, which may serve in engineering applications, including switchable electromagnetic metamaterials, morphing structures, and bionic robots.
A trait-based understanding of wood decomposition by fungi
Authors: Lustenhouwer Nicky , Maynard Daniel S. , Bradford Mark A. , Lindner Daniel L. , Oberle Brad , Zanne Amy E. , Crowther Thomas W.
Published: May 2020

Significance

Fungi play a key role in the global carbon cycle as the main decomposers of litter and wood. Although current climate models reflect limited functional variation in microbial groups, fungi differ vastly in their decomposing ability. Here, we examine which traits explain fungal-mediated wood decomposition. In a laboratory study of 34 fungal isolates, we found that decomposing ability varies along a spectrum from stress-tolerant, poorly decomposing fungi to fast-growing, competitive fungi that rapidly decompose wood. We observed similar patterns in a 5-y field experiment, in which communities of fast-growing fungi more rapidly decomposed logs in the forest. Finally, we show how linking decomposition rates to known spatial patterns in fungal traits could improve broad-scale predictions of wood decomposition by fungi.
Single-nucleus RNA sequencing of mouse auditory cortex reveals critical period triggers and brakes
Authors: Kalish Brian T. , Barkat Tania R. , Diel Erin E. , Zhang Elizabeth J. , Greenberg Michael E. , Hensch Takao K.
Published: May 2020

Auditory experience drives neural circuit refinement during windows of heightened brain plasticity, but little is known about the genetic regulation of this developmental process. The primary auditory cortex (A1) of mice exhibits a critical period for thalamocortical connectivity between postnatal days P12 and P15, during which tone exposure alters the tonotopic topography of A1. We hypothesized that a coordinated, multicellular transcriptional program governs this window for patterning of the auditory cortex. To generate a robust multicellular map of gene expression, we performed droplet-based, single-nucleus RNA sequencing (snRNA-seq) of A1 across three developmental time points (P10, P15, and P20) spanning the tonotopic critical period. We also tone-reared mice (7 kHz pips) during the 3-d critical period and collected A1 at P15 and P20. We identified and profiled both neuronal (glutamatergic and GABAergic) and nonneuronal (oligodendrocytes, microglia, astrocytes, and endothelial) cell types. By comparing normal- and tone-reared mice, we found hundreds of genes across cell types showing altered expression as a result of sensory manipulation during the critical period. Functional voltage-sensitive dye imaging confirmed GABA circuit function determines critical period onset, while Nogo receptor signaling is required for its closure. We further uncovered previously unknown effects of developmental tone exposure on trajectories of gene expression in interneurons, as well as candidate genes that might execute tonotopic plasticity. Our single-nucleus transcriptomic resource of developing auditory cortex is thus a powerful discovery platform with which to identify mediators of tonotopic plasticity.
Cycling the city
Authors: Lipovsky Caroline
Published: May 2020

Using articles from two major French newspapers of contrasting ideological viewpoints, this study seeks to explore their representation of cycling the city, and their potential to position readers to view cycling favourably or unfavourably. The analysis, drawing on systemic functional linguistics’appraisalframework, highlights the ways in which readers of bothLe FigaroandLe Mondeare positioned to take a positive view of cycling through their listings of the benefits of cycling or praise of bicycle-sharing systems. Conversely, readers may embrace a negative view through their reading about cycling casualties and safety issues. The analysis also shows that a reader ofLe Mondemight feel more inclined to take up cycling than a reader ofLe Figaro.
Restriction of memory B cell differentiation at the germinal center B cell positive selection stage
Authors: Toboso-Navasa Amparo , Gunawan Arief , Morlino Giulia , Nakagawa Rinako , Taddei Andrea , Damry Djamil , Patel Yash , Chakravarty Probir , Janz Martin , Kassiotis George , Brink Robert , Eilers Martin , Calado Dinis Pedro
Published: May 2020

Memory B cells (MBCs) are key for protection from reinfection. However, it is mechanistically unclear how germinal center (GC) B cells differentiate into MBCs. MYC is transiently induced in cells fated for GC expansion and plasma cell (PC) formation, so-called positively selected GC B cells. We found that these cells coexpressed MYC and MIZ1 (MYC-interacting zinc-finger protein 1 [ZBTB17]). MYC and MIZ1 are transcriptional activators; however, they form a transcriptional repressor complex that represses MIZ1 target genes. Mice lacking MYC–MIZ1 complexes displayed impaired cell cycle entry of positively selected GC B cells and reduced GC B cell expansion and PC formation. Notably, absence of MYC–MIZ1 complexes in positively selected GC B cells led to a gene expression profile alike that of MBCs and increased MBC differentiation. Thus, at the GC positive selection stage, MYC–MIZ1 complexes are required for effective GC expansion and PC formation and to restrict MBC differentiation. We propose that MYC and MIZ1 form a module that regulates GC B cell fate.
KRAS or BRAF mutations cause hepatic vascular cavernomas treatable with MAP2K–MAPK1 inhibition
Authors: Janardhan Harish Palleti , Meng Xiuling , Dresser Karen , Hutchinson Lloyd , Trivedi Chinmay M.
Published: May 2020

Human hepatic vascular cavernomas, the most common benign tumor of the liver, were described in the mid-1800s, yet the mechanisms for their formation and effective treatments remain unknown. Here, we demonstrate gain-of-function mutations in KRAS or BRAF genes within liver endothelial cells as a causal mechanism for hepatic vascular cavernomas. We identified gain-of-function mutations in KRAS or BRAF genes in pathological liver tissue samples from patients with hepatic vascular cavernomas. Mice expressing these human KRASG12D or BRAFV600E mutations in hepatic endothelial cells recapitulated the human hepatic vascular cavernoma phenotype of dilated sinusoidal capillaries with defective branching patterns. KRASG12D or BRAFV600E induced “zipper-like” contiguous expression of junctional proteins at sinusoidal endothelial cell–cell contacts, switching capillaries from branching to cavernous expansion. Pharmacological or genetic inhibition of the endothelial RAS–MAPK1 signaling pathway rescued hepatic vascular cavernoma formation in endothelial KRASG12D- or BRAFV600E-expressing mice. These results uncover a major cause of hepatic vascular cavernomas and provide a road map for their personalized treatment.
High-resolution spectroscopy of gaseous 83mKr conversion electrons with the KATRIN experiment
Authors: Altenmüller K , Arenz M , Baek W-J , Beck M , Beglarian A , Behrens J , Bergmann T , Berlev A , Besserer U , Blaum K , Block F , Bobien S , Bode T , Bornschein B , Bornschein L , Brunst T , Buzinsky N , Chilingaryan S , Choi W Q , Deffert M , Doe P J , Dragoun O , Drexlin G , Dyba S , Edzards F , Eitel K , Ellinger E , Engel R , Enomoto S , Eversheim D , Fedkevych M , Formaggio J A , Fränkle F M , Franklin G B , Friedel F , Fulst A , Gil W , Glück F , Ureña A Gonzalez , Grohmann S , Grössle R , Gumbsheimer R , Hackenjos M , Hannen V , Harms F , Haußmann N , Heizmann F , Helbing K , Hickford S , Hilk D , Hillesheimer D , Hinz D , Howe M A , Huber A , Jansen A , Kellerer J , Kernert N , Kippenbrock L , Klein M , Kopmann A , Korzeczek M , Kovalík A , Krasch B , Kraus M , Lasserre T , Lebeda O , Letnev J , Lokhov A , Machatschek M , Marsteller A , Martin E L , Mertens S , Mirz S , Monreal B , Neumann H , Niemes S , Off A , Osipowicz A , Otten E , Parno D S , Plischke P , Pollithy A , Poon A W P , Priester F , C-O Ranitzsch P , Rest O , Robertson R G H , Roccati F , Rodenbeck C , Röllig M , Röttele C , Ryšavý M , Sack R , Saenz A , Schimpf L , Schlösser K , Schlösser M , Schönung K , Schrank M , Seitz-Moskaliuk H , Sentkerestiová J , Sibille V , Slezák M , Steidl M , Steinbrink N , Sturm M , Suchopar M , Suesser M , Telle H H , Thorne L A , Thümmler T , Titov N , Tkachev I , Trost N , Valerius K , Vénos D , Vianden R , Hernández A P Vizcaya , Weber M , Weinheimer C , Welte S , Wendel J , Wilkerson J F , Wolf J , Wüstling S , Zadoroghny S , Zeller G
Published: May 2020

In this work, we present the first spectroscopic measurements of conversion electrons originating from the decay of metastable gaseous 83mKr with the Karlsruhe Tritium Neutrino (KATRIN) experiment. The obtained results represent one of the major commissioning milestones for the subsequent direct neutrino mass measurement with KATRIN. The successful campaign demonstrates the functionalities of the KATRIN beamline. Precise measurement of the narrow K-32, L3-32, and N2,3-32 conversion electron lines allowed to verify the eV-scale energy resolution of the KATRIN main spectrometer necessary for competitive measurement of the absolute neutrino mass scale.
Phase diagram of the frustrated FCC antiferromagnet from effective-field theory
Authors: Ehteshami Hossein , Ackland Graeme J
Published: May 2020

The phase diagram of a face-centred cubic (FCC) antiferromagnet is calculated from the effective field theory (EFT) of Honmura and Kaneyoshi taking into account not only the effect of interaction with nearest neighbours, J
1, but also the effect of second neighbours, J
2. The phase diagram for the nearest neighbour case away from the triple point, which in our calculations is predicted to be at H = 4 and T = 0, is close to cluster variation method (CVM) and Monte Carlo (MC) results. Similar to MC and CVM predictions, we observe that the increasing second neighbours interaction pushes the triple point towards zero field. Our calculations also show that for α = −J
2/J
1 = 0.3, the triple point merges with the transition point of the L10 phase, one of the ground states, at H = 0 and changes the nature of phase transition from first- to second-order, in full agreement with Monte Carlo predictions. The phase diagram with the effect of second neighbours calculated for several values of α are in good agreement with available MC and CVM predictions.
Shape memory alloy tube actuators inherently enable internal fluidic cooling for a robotic finger under force control
Authors: Ades Craig J , Dilibal Savas , Engeberg Erik D
Published: May 2020

This paper presents the design, control and evaluation of a novel robotic finger actuated by shape memory alloy (SMA) tubes which intrinsically afford an internal conduit for fluidic cooling. The SMA tubes are thermomechanically programmed to flex the robotic finger when Joule heated. A superelastic SMA plate provides a spring return motion to extend the finger when cooling liquid is pumped through the internal channel of the SMA tube actuators. The mechanical design and nonlinear force controller are presented for this unique robotic finger. Sinusoidal and step response experiments demonstrate excellent error minimization when operated below the bandwidth which was empirically determined to be 6 rad s−1. Disturbance rejection experiments are also performed to demonstrate the potential to minimize externally applied forces. This method of internal liquid cooling of Joule heated SMA tubes simultaneously increases the system bandwidth and expands the potential uses of SMA actuators for robotic applications. The results show that this novel robotic finger is capable of precise force control and has a high strength to weight ratio. The finger can apply a force of 4.35 N and has a mass of 30 g. Implementing this design into wearable prosthetic devices could enable lightweight, high strength applications previously not achievable.
Structural Analysis of Alloy Wheels
Authors: Hawkins George , Kumar Vikas
Published: May 2020

The wheel of a car plays a pivotal role to endure the weight applied on it. Usually spokes behave as the supports between the hub and the rim. These spokes must have adequate stiffness and strength to dodge the failure of the wheel. In current days these wheels are comprised of, magnesium alloy, steel and aluminum alloy. To decrease the weight of the wheel, numerous wheel designs are executed and applied for automobiles. As regard to the study of the vehicle stability, it is adequate to perform the structural analysis of the wheels so as to know the equivalent modal considerations.

In this work, a Cad model of a typical alloy wheel was designed in SOLIDWORKS software and dynamic analysis is performed on this model. The Stress analysis and Fatigue analysis was done on the chosen design. By observing the results we can see whether the design of wheel and the material is feasible or not under applied load conditions. A comparative study is performed by using results of the analysis of the wheel using different materials. The materials used are: Magnesium Alloy, Stainless Steel and Aluminum Alloy and Titanium Alloy in the end best suitable material for the wheel is determined
Comparative Analysis of 5 level, 7 level and 9 level Half-Bridge Modular Multilevel Converter
Authors: Jatin  , Agarwal Anshul , Kumar Jadoun Vinay
Published: May 2020

This paper uses the topology of Modular Multilevel Converter (MMC) to demonstrate Direct Current (DC) / Alternating current (AC) conversion implementation. For drive applications, a theoretical background is presented. The 5-stage MMC switching system is explained. The simulation was performed using cascaded interconnection of half-bridge submodules for single legs of three phase 5 level, 7 level and 9 level modular multilevel inverters. This paper is intended to examine Total Harmonic Distortion (THD) for different voltage stages.
Numerical Investigation On Free Convection Around Elliptical Cylinders In A Circular Enclosure
Authors: Patpatiya Parth , Yadav Bhavana , Jain Soumya , Baura Srishti
Published: May 2020

This paper acquaints with the study of steady state laminar natural convection around heated elliptical plate placed inside a relatively cold circular enclosure subjected to varying number of elliptical plates (2, 3 and 4), Rayleigh number (104, 105, 106) and centre to centre distance between the elliptical plates(xc). The effect of these three parameters are observed and analyzed based on the simulation performed using Finite Volume Method (FVM) based solver. Heat transfer characteristics are analyzed for all the cases in terms of isotherms, streamlines. Plots of average nusselt number along active enclosure walls and along the fringe of the inner Cylinders are illustrated in a graphical manner. Two dimensional study is followed by considering air as the fluid in the enclosure (Prandlt number=0.71). Grid independence test followed by validation of experimental results is carried out. Eventually parametric analysis concludes by analyzing the effects of altering the various parameters on the strength of buoyancy affected flow.
Assessment of the use of FEM for computation of Electromagnetic Forces, Losses and Design of Transformers
Authors: Vibhuti  , Walia Genius , Bhalla Deepika
Published: May 2020

This paper reviews the published work on power transformers for assessment of the electrical, magnetic losses, and electromagnetic forces produced during normal and short circuit conditions. The different methods used are analytical method, integral equation method, boundary element method, and finite element method (FEM). The copper losses and eddy currents within the copper conductors/windings need to be assessed to estimate the heat generate and compute the efficiency. The knowledge of the eddy current losses in the core and stray losses in each component of the transformer can help in the design improvement. Earlier 2D FEM and now 3D FEM has been used to evaluate the electromagnetic flux under normal conditions, the effect of the in-rush phenomenon, assessment of mechanical strength of windings, insulation, computation of short circuit forces and need of the mechanical support components during fault conditions. This paper gives an overview of the work done on the computation of electromagnetic forces, losses, and design of transformers using FEM to assess the scope for further work.
Mathematical modelling skills of prospective mathematics teachers in problem-solving
Authors: Hapizah  , Mulyono B
Published: May 2020

This paper aims to explain the results of the analysis of mathematical modelling skills of prospective mathematics teacher in problem-solving. The data collection used is a written test. The research subjects were prospective mathematics teachers at Mathematics Education Department of Teaching and Education Faculty of Universitas Sriwijaya. The results of the study state that mathematical modelling skills of prospective mathematics teachers in problem-solving are categorized sufficient.
On teaching learning for proportion using musi tour context
Authors: Nursa N F , Hartono Y , Somakim
Published: May 2020

This study aims to produce a learning trajectory that assist student to understand in the study of proportion. The learning approach used Pendidikan Matematika Realistik Indonesia (PMRI). This research used design research that are three phases, preparing for the experiment, the design experiment, and the retrospective analysis. Musi tour context used in the series of learning activities to developing Hypothetical Learning Trajectory (HLT). Then, HLT has been designed compared with actual learning during the teaching experiment. Theoretical development implemented through an interactive process on three phases of design research that aims to giving contribution about Local Instruction Theory (LIT) for assist student studying proportion. Interviews, video recordings, photograph and giving pretest and posttest are undertaken to collect the data. The result of the retrospective analysis is Musi tour context as a learning model can assist student understand in the study of proportion.
Attitude of middle school students toward mathematical modelling
Authors: Fitri P , Hiltrimartin C , Indaryanti  , Hapizah
Published: May 2020

This research is a descriptive study that aims to determine student attitudes towards mathematical modeling in secondary schools in Palembang. Subjects of this study involves graders VII.6 of SMP Negeri 1 7 Palembang, graders X.IPA.1 Palembang SMA 02 and SMA 10 XI.IPA.5 class Palembang. The data collection technique in this study was a written questionnaire. Questionnaire data analysis is based on a Likert Scale Questionnaire. The results of this study are students’ attitudes are quite good towards problem solving in mathematical modeling. This is evidenced by the results of the data as much as 38.62 %.
Mathematical proof analysis using mathematical induction of grade XI students
Authors: Emeira G , Hapizah  , Scristia
Published: May 2020

The purpose of this study is to provide an overview on how students do mathematical proof using mathematical induction through the activity of compiling and validating proof. It is known that mathematical induction is a proof used to prove the truth of a mathematical statement related to natural numbers. The subjects of this study were 34 students of grade XI SMA Negeri 13 Palembang. The results showed that (1) students were able to prove on the base of the induction step by showing the truth when n is assumed by one member of a natural number, (2) students were able to make a mathematical induction hypothesis by assuming the statement n = k is true, (3) students still make mistakes in performing mathematical induction steps precisely on the part when doing algebra manipulation to prove n = k + 1 is true from the statement n = k that has been considered true, and (4) Students still do not understand the concept of mathematical induction as indicated by the large number of students unable to do the activities of compiling proof by mathematical induction and there are still some students who write conclusions on the activity of compiling proof that the statement is proven true without showing the truth of the induction step
Scaffolding in mathematical problem-solving
Authors: Arifin S , Zulkardi  , Putri R I I , Hartono Y , Susanti E
Published: May 2020

This research is a descriptive study that aims to describe the scaffolding conducted by the teacher in helping students and students’ strategies in solving problems. The subjects of this research were 20 students grade IX of junior high school number 3 Palembang. The instruments used in this study were field notes, observation sheets, student worksheets and interviews. Based on the research results, scaffolding can help solve students’ problem solving. Scaffolding in form a written questions and directed guidance with step by step are as a bridge in solving problems. Scaffolding which starts with sketching can be teacher feedback in knowing the concept of student images. Differences in students solution and student strategies are influenced by prior knowledge, background experience, intellectual abilities, and writing abilities in mathematical language.
Mathematics reasoning through inquiry learning model
Authors: Khansa N , Susanti E , Indaryanti  , Sari N , Simarmata R H
Published: May 2020

This research is a descriptive study that aims to study mathematical thinking aspects of reasoning through inquiry learning models on the slope of line. This research focus is on deductive deduction. The subject of this study were 3 students in class VIII of SMP Negeri 1 Indralaya Utara. Based on the results of tests and interviews, it can be concluded that students have mathematical thinking. Students can make conclusions based on a general picture. However, one of the indicator is using algorithms in calculations. There are some students still have difficulty in calculations because of constraints in arithmetic operations and errors in determining the coordinates which are the prerequisite material in this learning. Interesting, students unable to make correct conclusions.
The 6th grade students’ view in understanding mathematics through reading mathematics textbook
Authors: Turidho A , Maharani Y , Darmawijoyo
Published: May 2020

This research aims to describe students’ views in understanding mathematics by reading a mathematics textbook. The subjects of this research were 6 students on grade VI at Singapore International School (SIS) Palembang. This is descriptive research. The research instruments were interviews and questionnaires. Based on the results, 50% of students read a mathematics textbook by reading definitions or rules, learning examples of the problems and doing exercises. And 50% of students read a mathematics textbook by learning examples of the problems, reading definitions or rules and doing exercises. In understanding mathematics, 16.7% of students felt understood mathematics textbook after understood the definitions or rules, 33.3% of students felt understood mathematics textbook after doing the mathematics problems, 33.3% of students felt understood mathematics textbook after doing exercises and 16.7% of students felt understood mathematics textbook after doing mathematics problems and understanding definitions or rules.
Development of interactive multimedia for learning physics based on traditional games
Authors: Wiyono K. , Ismet I. , Saparini S.
Published: May 2020

This study aims to produce interactive multimedia based on valid and practical traditional games on impulse and momentum material, as well as the effective use of interactive multimedia. This research implements Rowntree development model which consists of planning stage, development stage and evaluation stage. The evaluation stage uses Tessmer formative evaluation (include of self evaluation, expert review, one-to-one evaluation, small group, and field test. Data collection techniques used were expert validation form, student response questionnaire, and learning outcome test. The results of expert validation obtained content validity by 81.56% the category is valid and layout validity 91.87% the category is very valid. The practicality test results at one to one stage were 96.21% the category was very practical and the small group stage was 92.42% the category was very practical. Furthermore, the effectiveness of the use of interactive multimedia developed to learning outcomes is obtained through the field test stage with an n-gain of 0.51 including the medium category. Based on this study it can be concluded that interactive multimedia based on traditional games as an innovation to preserve local wisdom in impulse and momentum materials worthy of use.
Virtual and mixed reality in the study of the geometry of the crystal lattice
Authors: Zakharov P V , Vdovin R S , Markidonov A V , Kochkin A S , Vdovin A S
Published: May 2020

The article considers the possibility of using virtual and mixed reality in studying the geometry of the crystal lattice in the framework of the course of solid state physics. The application of mixed and virtual reality technologies in the study of various branches of physics is receiving more and more attention. Virtual reality headsets were used in practical and laboratory classes, where students had to create crystal structures and carry out modeling of various processes. When studying complex spatial objects of crystallography, virtual reality technology allowed students to familiarize themselves with the object of study in more detail, understand the structure of crystals and, accordingly, complete the task in a timely manner. At the same time, the prolonged use of virtual reality headsets led to rapid fatigue of students.
Analysis of the stressed-deformed state of a pipeline with curved line parts in frozen soil
Authors: Kulakov P A , Rubtsov A V , Afanasenko Z R , Mukhametzyanov V G , Bayazitov M I
Published: May 2020

The paper presents a methodology for calculating the stress-deformed state of the pipeline. All dimensions required for calculations are given. The object of research is a section of an elevated trunk pipe with curved sections transporting oil. The stress-deformed state of the pipeline was calculated considering and without considering soil conditions using the SolidWorks PC. According to the results of all the calculations of the stress-deformed state of the pipe with curved sections, the dependence of the stress distribution over the zones of the pipeline on the strength of frost heaving of the soil is derived.
Radial profile of dissipation rate for turbulent flow of incompressible fluid in round direct pipe based on generalized local balance model
Authors: Balonishnikov Alexander , Opalikhina Olga
Published: May 2020

The article is focused on the problem of generalized local balance turbulence model. Generalized local balance turbulence model is considered. The one-parameter turbulence model is based on semi-empirical dissipation rate transport equation with negative coefficient of diffusion. To determine a coefficient of this equation, Laplace’s method of asymptotic estimation of a double integral is used. To compute radial dissipation profile the turbulence model is applied to the pipe flow. The known wall and axial functions are used as boundary conditions. The turbulence model is applied to the pipe flow to compute radial dissipation profile, well-known wall and axial functions are used as boundary conditions. Comparisons with known experimental data are given.
Impact of IoT on the automation of processes in Smart Cities: security issues and world experience
Authors: Mentsiev Adam U , Engel Mahdi V , Gudaeva Diana-Madina M-E
Published: May 2020

The idea of Smart Cities is inconceivable without automating the basic services and processes such as traffic, communication, and data sharing. It is imperative for smart cities to make use of all the fluid connections that IoT offers in order to achieve its goal of providing quality life to people living in it, through the incorporation of smart technologies. Smart cities seek to connect anything that has an on and off switch to an integrated network that contains all the devices connected to the internet, from toasters to rigs in oil fields. This research explores security issues of IoT and considers the best practices if implementation of IoT in different countries around the world.
Temperature condition influence analysis on the mechanoactivated wheat dielectric constant
Authors: Buzunova M Y , Bonnet V V
Published: May 2020

The biochemical properties of the grain depend significantly on the effects of heat and moisture. By regulating the external conditions, it is possible to influence the biochemical processes in grain, to change its biochemical characteristics. The analysis of temperature dependence of electrophysical properties in fine-dispersed non-equilibrium heterogeneous medium has been carried out on the example of mechanically activated wheat. It is shown that the disordering of fine-dispersed grain structure and change of temperature condition have a significant influence on its dielectric properties. The value of the real component of the dielectric constant depends on the degree of samples dispersity, temperature and humidity conditions and the frequency of the external electric field. The study of the dielectric constant spectra showed that the maximum growth of the dielectric parameters corresponds to a temperature close to 100°C and its value increases for wheat samples with lower particles dispersity. The frequency of the external electric field has a significant influence on the dielectric parameters of wheat samples with different degrees of dispersity, which is associated with changes in the structure of the non-equilibrium system as a result of mechanical activation.
Narrow-band correlation processing of signals in a phase direction-finding
Authors: Zhukov A O , Valyaev I N , Kovalenko V P , Turlov Z N , Novikov A S , Kartsan I N , Malanina Yu N
Published: May 2020

The article deals with the phase method of direction finding, based on the dependence of the phase difference of the signals received by the antennas, as well as the correlation signal processing in the phase direction finding, which will assess the possibility of signal direction finding of the “Spectrum-RG” spacecraft, derived in the neighborhood of the L2 Lagrange point located at a distance of one and a half million kilometers from Earth.
Development of forecasted values of specific norms for the issues of produced products in industrial enterprises
Authors: Rakhmonov I U , Tovbaev A N , Nematov L A , Sh Alibekova T
Published: May 2020

This article discusses the issues of determining the predicted values of rationing the power consumption of industrial enterprises. For a certain pattern of change in power consumption and specific power consumption, hourly productivity was studied, which determines the performance of units. On the basis of the predicted values of the output volume, the norms of energy consumption were developed, which are reflected taking into account its specifics, the energy intensity of the products. In developing the norm, the calculation method was adopted based on the analysis of static data for a number of previous years on actual energy consumption, the volume of output of factors affecting their change.
Theoretical research and development optoelectronic communication devices
Authors: Kh Abduraimov E , Kh Khalmanov D , Nurmatov B A , Dusmukhamedova S A , Khamidova N E
Published: May 2020

Nowadays, with the wide automation of production processes and the introduction of automatic control systems, the requirements for the creation of contactless electric devices have substantially increased. The development of power semiconductor electronics allows the solution of complex technical problems aimed at improving the efficiency of electrical devices. The leading role in this direction is given to optoelectronic devices and thyristor devices, which provide contactless switching processes and galvanic isolation, and have improved transient and frequency characteristics The article deals with the creation of compact, reliable, highspeed optoelectronic contactless voltage relays with an extended service life, combining a sensitive system and a powerful actuator having a sinusoidal shape of the voltage curve at the load. Theoretical, experimental studies and the principle of operation of an optoelectronic contactless voltage relay with time delay are given.
Electrical testing of small-series multi-chip microcircuit samples combining Wire Bond and Flip-Chip technologies
Authors: Kirienko D A , Yu Ershova N , Putrolaynen V V , Lunkov P V , Marcinkevich K R
Published: May 2020

The paper provides a technical solution and methodology for conducting automated electrical and functional testing of small series samples of multi-chip assemblies. The results of multi-chip assembly samples testing combining Wire Bond and Flip-Chip technologies are presented. Based on the test results, defects that occur during the packaging process are localized and the assembly stages at which these defects occur are determined.
Magnetocaloric effect in polycrystalline cobalt
Authors: Urinov Kh O , Jumanov Kh A , Khidirov A M , Kh Urinov S , Abdiyev J M , Jumaboyev T A , Eshmirzayev M R
Published: May 2020

The article discloses an experimental and theoretical study of the magnetocaloric effect in a uniaxial ferromagnetic crystal on the orientation phase transition. The proposed by authors method based on heat exchange in a layered structure, polycrystalline cobalt and a film of heat-sensitive material with metal-dielectric phase transition is promoted. The results of the experiment are made in accordance with the general expression for ferromagnets.
Methods to ensure durability and improvement of reliability of bridge cranes of General purpose during their operation
Authors: Akhtulov A L , Kirasirov M O , Kirasirov O M
Published: May 2020

The paper notes that lifting and transport machines are an integral part of any type of production, since they serve all types of technological processes. Cranes greatly contribute to the smooth operation of the process equipment, so ensuring the quality and increasing the productivity of the crane equipment allows you to improve the performance of the process equipment. The directions and possible ways of improving the designs of General-purpose bridge cranes to increase the durability and improve the reliability of their operation are considered. The main reasons for the need to upgrade bridge cranes in operation are given. The analysis of the main principles of crane equipment modernization is given. The issues of modernization of load-lifting bridge cranes in order to increase productivity, ensure structural improvement, safety in operation, and technical and economic efficiency are considered. To determine the degree of manufacturability of the design, indicators are proposed, for which the classification according to the main evaluation criteria is given. The economic assessment of the feasibility of modernizing the crane economy is given.
Mixing strategies in the matrix game
Authors: Assaul Victor N , Lashchenov Vladimir K
Published: May 2020

The article considers the sequential strategies mixing in the matrix game as an algorithm for finding the optimal player’s strategy. Strategies are mixed in such a way as to obtain a row of the payment matrix with constant elements. As a result, such a row is deleted as dominated, or determines the value of a game. The games with two moves of the second player, which are solved without the use of the simplex method, are analyzed at each stage.
Working capital as a multi-format process for enterprise management in modern production
Authors: Novikov S V , Tikhonov G V
Published: May 2020

This article discusses the methodology of working capital management in a company in a competitive environment. Furthermore, it studies the introduction of advanced Information technologies (IT) that identify hidden resources and potentials, regulate and optimize production processes to improve operational production management.
The linear network coding optimization in hybrid ARQ/FEC system to counteract head-of-line blocking in queue
Authors: Britvin N V , Karpukhin E O
Published: May 2020

The problems of systematic linear network coding optimization and generic matrix generation methods are considered in this article. The most efficient generation method is a random matrix filling with prime numbers. A model of data transfer system was developed that allowed to assess the telecommunication system packet loss rate using various methods. The first method involves a packet loss rate calculation using the binomial distribution law. In order to find the optimal length of the information and coding sequences, the enumeration of the possibilities based on the calculation results is made. The optimality criteria are maximum code rate and minimum coding sequence length upon the condition that packet loss rate is zero. This method provides high accuracy and allows to quickly obtain a large number of optimal lengths of the information and coding sequences. However, the method cannot be modified to be used for the packet correlated loss calculation in case of the network overload and data transfer pending via wireless connection. The second method relies on the simulation models which allow to find the optimal lengths of the information and coding sequences using multiple test data transmission in the simulation environment with different characteristics (modulation methods, coding, channel models).
Problems of metrological support of methods for determining the corrosion rate of offshore platforms with insufficient source data
Authors: Starokon I V
Published: May 2020

Offshore stationary platforms are used in the extraction of resources on the shelf (oil, gas, coal, steel and etc.). Offshore platforms are exposed to corrosion, which can lead to the destruction of the structural elements of the platforms. To assess the value of corrosion losses, ultrasonic measurement of the wall thickness of platform elements is used, which gives an understanding of their actual wear. In some cases, there is no initial information on the wall thickness of the platform elements. The absence of this information does not allow the calculation of the corrosion rate of platform elements and the determination of its residual life. The article proposes a method based on probability theory, which allows you to calculate the initial wall thickness of the platform elements in the absence of initial data on the initial thickness.
Increasing the strength of welded thin-walled axisymmetric vessels made of corrosion-resistant steel
Authors: Vasechkin M A , Yu Davydov O , Egorov V G , Egorov S V , Matveeva E V
Published: May 2020

Structural elements of thin-walled vessels operating under internal pressure are mainly made from sheet blanks using welding operations. To reduce the negative impact of welds in the manufacture of thin-walled vessels, it is proposed to use separate calibration processes by compressing vessel parts with subsequent welding and their joint calibration by distribution and rotary rolling. Compression calibration ensures the accuracy of matching of the abutting annular edges of the vessel parts. During rotary rolling, the welds are simultaneously smoothed and the strength characteristics are improved due to plastic hardening caused by thinning and leveling the wall thickness of the vessel body. Based on the conducted research, technological recommendations have been developed for the manufacture of thin-walled vessels of increased strength from corrosion-resistant steels.
Monitoring and assessment of the state of floodplain ecosystems exposed to oil and gas complex wastes
Authors: Strizhenok A V , Fedorova A V
Published: May 2020

Formation of a huge amount of industrial waste is one of the most urgent problems of the mineral resource complex today. It accumulates on the surface of the Earth, disposed of by burning or stored in anthropogenic arrays, thereby providing a complex and lasting negative impact on all components of the natural environment. This problem is especially acute in regions with a high concentration of enterprises of the mineral resource complex. The results of a scientific study on monitoring the state of the floodplain ecosystems of the Ob River, as one of the most reliable indicators of the intensification of the anthropogenic load in the region, are presents in the article. The progress of the research and the results of computer processing of the data are described in the article in detail. In addition, comparative characteristics of the state of some species of plant communities over a three-year period are given.
Mapping distributions in the entropy-parametric space
Authors: Polosin V G
Published: May 2020

The paper discusses the possibility of approximate identification of asymmetric models in the space of information and probability signs of the sample data distributions. The paper contains a description of the features of the method for displaying asymmetric models in the entropy-parametric space of distribution signs. In particular a brief analysis of the shortcomings of the mapping of distributions in the space of parametric signs of asymmetry and kurtosis is given. For the construction a space of distribution signs, the author is proposed an entropy coefficient for asymmetric distributions that it is used as an independent interval informational estimate for observation sample data distribution. The material is illustrated by the example of a widespread family of generalized gamma distribution.
Multi-target method for small unmanned vehicles parameters remote determination by microwave radars
Authors: Kuptsov V D , Ivanov S I , Fedotov A A , Badenko V L
Published: May 2020

This article explores the properties of the multi-target method for small unmanned vehicles parameters remote determination by microwave radars, which allows to expand significantly the range of unambiguously determined speeds of unmanned vehicles. The reasons of occurrence of false targets and their number in the mode of the parameters simultaneous measurement for the set of unmanned vehicles are identified. Using a computer experiment in LabVIEW, the probability of the unmanned vehicles true parameters determination at various ratios of the signal to noise at the input of the radar receiver in multi-target mode was investigated.