bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Aggregate Dynamics of Lower Court Responses to the US Supreme Court
Authors: Masood Ali S. , Kassow Benjamin J. , Songer Donald R. 
Published: August 2019

AbstractWe argue that given finite resources to review the large number of lower court decisions, Supreme Court justices should primarily be interested in aggregate responses to their precedents. We offer a theory in which the US Supreme Court drives aggregate responses to its decisions by signaling the utility of its precedents to judges on the lower courts. Specifically, we argue that lower court judges have a greater propensity to rely on a Supreme Court decision when the justices explicitly direct a lower court to consider a formally argued decision in its summary decisions. Our results demonstrate that such signals significantly increase the frequency with which the lower courts adopt the precedents of the US Supreme Court. We corroborate the causality of these links through qualitative analyses, distance matching methods, and simultaneous sensitivity analysis. Our study offers new and important insights on judicial impact and decision-making behavior in the American courts.
The stability of a skyrmion in a nanotube
Authors: Huo Xiaohong , Liu Yan 
Published: August 2019

Abstract
We study the stability of a skyrmion in a nanotube by using micromagnetic simulations. We find that skyrmions can exist stably in a nanotube within a moderate magnetic field range when the magnetic field is perpendicular to the center axis of the nanotube. In nanotubes the shape of the skyrmion is elliptical. The semimajor and semiminor axes of the ellipse depend on the magnetic field and the angular position of skyrmion. When the skyrmion has an angular displacement from the direction of magnetic field, its shape and size change greatly with the angular position of skyrmion. Also the topological number is dependent on the angular position of skyrmion. When the angular position of skyrmion reaches a critical value, the skyrmion annihilates. The critical angle that skyrmion can survive is not affected by the circular current density, but depends on the radius of nanotube and the strength of magnetic field.
Mimicking the cochlea with an active acoustic metamaterial
Authors: Rupin Matthieu , Lerosey Geoffroy , de Rosny Julien , Lemoult Fabrice 
Published: August 2019

Abstract
The human ear is a fascinating sensor, capable of detecting pressures over ten octaves of frequency and twelve orders of magnitudes. Here, following a biophysical model, we demonstrate experimentally that the physics of a living cochlea can be emulated by an active one-dimensional acoustic metamaterial. The latter solely consists on a set of subwavelength active acoustic resonators, coupled to a main propagating waveguide. By introducing a gradient in the resonators’ properties, we establish an experimental set-up which mimics the dynamical responses of both the dead and the living cochleae: the cochlear tonotopy as well as the low-amplitude sound amplifier are reproduced.
Teaching quantum mechanics in high-school ─ Discipline-Culture approach
Authors: Weissman E Y , Merzel A , Katz N , Galili I 
Published: August 2019

Abstract
This study presents a new approach to teaching quantum mechanics in high school physics courses facing the extremely deficient and fragmented treatment of quantum mechanics at present. The suggested curriculum adopts the new paradigm of discipline-culture in representing physics knowledge. In accordance, the curriculum is structured in nucleus-body-periphery emphasizing the principles (nucleus), their illustration (body) and their contrast with the alternative pictures in classical mechanics (periphery). The new curriculum for 30 teaching hours is presented. The results of an experimental application to 46 12th grade students in four groups shows a positive impact on students’ conceptual knowledge and students’ nature-of-science understanding. The benefits of the applied approach and limitations of the study are presented.
Colours in your pocket: smartphone-based spectrometers to investigate the quantum world
Authors: Malgieri Massimiliano , De Ambrosis Anna , Rosi Tommaso , Onorato Pasquale , Gratton Luigi M. , Oss Stefano 
Published: August 2019

Abstract
We designed a low cost spectrometer to be used by groups of students with an inquiry approach. This simple equipment allows to investigate the additive and subtractive models of colour formation, to study the selective absorption of a material and explain it from a microscopic point of view. The home made apparatus was used in several experiments showing the quantum nature of the absorption and production of light with the aim of bridging optics and modern physics.
Physics for skills development in preschool in Mexico.
Authors: Ramírez Díaz Mario Humberto 
Published: August 2019

AbstractPhysics has historically been a goal and as a media to reach out for other educational skills. Unfortunately, in Mexico preschool teachers lack tools to develop science in their little students. To help in this situation, we propose the use of “Einstein Box,” a set of toys where the kids can select and play with, then teachers explain the general physics concepts involved in the working of the toys. The results for the kids are amazing because they not only learn about basic physics, furthermore, mathematical thinking, social skills and verbal abilities, all around physics concepts.
Combining strategies to make General Physics lectures more attractive and to improve students’ performances
Authors: López G A , Alonso I , Sáenz J , Leonardo A , González-Rojí S J , González de Arrieta I , Echániz T , Unzueta I , Lafuente-Bartolome J , de la Pinta N , García-Goiricelaya P , Martinez-Perdiguero J , Gurtubay I G 
Published: August 2019

Abstract
Going one step further in the use and impact measurement of new strategies to improve the teaching-learning process during lecturing General Physics courses, the current contribution reports the last results/observations obtained by the authors on the combination of simple classroom experiments with active methodologies and new technologies (media). Cross-checking the answers in multiple choice questions done online during the lectures and in exams at the end of the term shows that this strategy has, at least partly, a positive effect on clarifying misconceptions. The overall opinion of the students was assessed and it showed that this lecturing approach is useful and motivating, making the lectures more attractive and stimulating eagerness to understand Physics.
Scaffolds to support the development of scientific skills in physics
Authors: Ferreira-Bautista J , Pifarré M 
Published: August 2019

Abstract
This paper responds to the social demand to equip learners with the skills capable to create solutions that are sustainable over time, to increasingly complex problems. To this end, this study designed implemented and evaluated an instructional process aimed to students’ development of scientific skills during the scientific inquiry process. A quasi-experimental study was designed in which participated 61 university students of physics university course participated in the study. The results show that the students of the experimental group developed higher level of scientific skills than the control group.
Physics in traditions: the ritual of the owners of the Mexican sky.
Authors: Espíndola. R. , Del Valle G. , Hernández G. , Muciño D. , Guijosa S. , Jiménez J. L. , Campos I. 
Published: August 2019

Abstract
Mexico is characterized by its immense cultural diversity, one culture of many is in the state of Veracruz where the Totonac culture lived. His developed of a ritual known as “The Papantla flyers”[1], which is related to fertility of the earth, this ritual consists of a group of five men who climb to the top of a 31-meter pole, tie a rope around their waist and throw themselves headlong into the void with open arms. A child, observing this ritual asks his father, “at the top, the pole has an engine that unrolls the rope and causes men to descend?”. In this work, we study the equations of motion associated to the trajectory of the men who are thrown into the void, through the design and construction of an experimental model. To compare the experimental results with the analytical solution obtained by proposing the analytical equation that describes its movement, at the same time emphasizing the use of computational tools for simulation of the model using Easy Java Simulation.
Teacher students’ beliefs about teaching physics and their teacher education
Authors: Krumphals I , Hopf M , Haagen-Schützenhöfer C 
Published: August 2019

Abstract
It is beyond doubt that teacher education plays a crucial role in the development of the educational system. Following the educational reconstruction for teacher education model [1], a clarification of teacher students’ beliefs seems mandatory in order to improve the education of future physics teachers. The main aim of this research project was to determine beliefs of physics teacher students about high quality physics instruction at school. Therefore, interviews with 23 physics teacher students and an additional case study with six teacher students were conducted. Several beliefs of teacher students’ such as experiments rise students’ interest and with the help of experiments physical contents can be memorized better were found.
The use of history of science on physics teaching as a social representation from pre-service teachers
Authors: Rodrigues E V , Borges A , Pietrocola M 
Published: August 2019

Abstract
In this work we used the Social Representation theory and one of its methods for investigating social representations of a group of undergrad physics students (N = 77), taking teaching credential, regarding the usage of History of Science as teaching strategy. Our empirical data showed a social representation with a nucleus consisting of elements from History of Science more as a contextualization tool and pragmatics science products than as a human process. The lack of a representation of science as process point out the need of rethinking the undergrad curriculum in order to expand students views on the nature of science.
Enhancing Scientific Inquiry by Mathematical Reasoning: Case of Applying Limits to Model Motion of a System of Objects
Authors: Sokolowski Andrzej 
Published: August 2019

Abstract
Mathematics and physics constitute parts of STEM that are widely recognized as a leading platform in contemporary education. While the effects of the methods of mathematics on discoveries in physics are unquestionable, using mathematical reasoning to enhance understanding of physics is still being researched. This study is posited to contribute to that research, and it investigates students’ skills to apply limiting the analysis to determine the acceleration of two objects connected by a massless string. Twenty-five (N=24) first-year students enrolled in the algebra-based college physics course took part in this case study. While the pretest showed that the students did not consider limits to answer questions that required limiting analysis, designed instructional unit whose goal was to bring forth the technique helped apply limits and made the solution process more explicit. Posttests results supported the study thesis that integrating more sophisticated mathematical apparatus into the analysis of physical systems opens a gate not only for advancing students’ scientific inquiry skills, but also their general STEM disposition.
A perspective on Interactive Lecture Demonstrations as a computer supported collaborative learning (CSCL) activity
Authors: Chaudhury S. Raj , Canatsey Sarah , Ward Phillip J. 
Published: August 2019

Abstract
Active learning designs that leverage the power of information and computer technologies (ICT) can vary tremendously in how they engage students – individuals, small groups or whole class. Interactive lecture demonstrations (ILDs) are instructor-led activities which engage the whole class and are designed address students’ mental models of core concepts in the discipline. The use of ICT allows for real time experiments conducted using sensors, simulations and even data analysis as the core of the activity. In this perspectives paper, we analyze the features of traditional ILDs through the lens of the field of computer supported collaborative learning (CSCL).
The Physics and the Chemistry of Michael Faraday to form for citizenship
Authors: Nogueira S R A , Cardoso F S , Carvalho F L C , Marinelli M O , Bezerra A S , Senra P R 
Published: August 2019

Abstract
In this paper we present a teaching-learning strategy based on the life of Faraday to provide knowledge of physics (electromagnetic induction) and chemistry (chemical bonds) and a wakening to citizenship. The strategy combined a film screening with experimentation and was applied with 4 classes of the first-grade secondary school in 2014 and 2016. In all classes the discussions about the movie and the student’s reports showed that they appropriated the specifics concepts, they got enchanted by Faraday’s life and became aware of their own capacity to build their future.
Numerical Simulation of Gas-Solid Two-Phase Flow and Deposition in a Novel Carbon Nanotubes Particles Trap
Authors: Geng Lei , Bai Wenjuan , Dong Fakui , Chu Dianming , Wang Lianlian , Zhou Yong , He Yan 
Published: August 2019

Abstract
The effects of gas-solid two-phase flow, flow velocity, model structure and temperature on deposition characteristics in Carbon nanotubes (CNTs) particles trap were simulated by Euler-Lagrangian model, adopt Realizable k–ε Model calculation of turbulent flow in trap, tracking of particle trajectories using stochastic orbital model. The simulated results are in good agreement with the experimental results, deposition of particles at orifice edge of baffle; The adhesion of particles to the wall surface is consistent with the phenomena presented by previous simulations. With the increase of temperature, the deposition rate of particles increases. The more the number of holes in baffle, the more particles are captured. At high wall temperature, the particle aggregation positions of concentric and heterocentric baffle trap are different. The deposition of the four wall particles in the concentric hole trap is obvious at the exit location, the particle deposition of heterocentric hole trap on baffle is obvious. For the vertical flow field, particles are preferentially deposited on the bottom baffle, and the heterocentric trap has a higher deposition rate than that of the concentric hole. The simulation reveals the difficult flow characteristics of particles in the trap, and the conclusions obtained are of great significance to improve the reliability of the design and amplification of the trap.
Shape Optimization and Analysis of a Low-resistance Mast
Authors: Xiang Chao , Li Baoren , Gong Yajun , Zeng Baoping 
Published: August 2019

Abstract
Aiming at the problem that the airfoil of WGN affects the motion resistance and noise, a set of general WEG airfoil design and optimization method is explored. First, the parameter design based on computational fluid dynamics computing method of WGN appearance is done. Then, the WGN appearance hydrodynamic characteristics was calculated with the airfoil design software XFOIL, and finally, the iterative optimization of the initial design of WGN appearance is done by the genetic algorithm, finally the fold down type SJZZWGN curve shape with low resistance and low noise is obtained to satisfy the mechanical properties. Finally, CFD software is used to analyse the optimization results and verify the rationality of the optimization results.
Numerical simulation of foam flow pressure drop in coiled tubing spiral section
Authors: Zhang Xiaoning , Sun Dongzhu , He Anle , He Zhenguo , Kong Lulin 
Published: August 2019

AbstractA user-defined function and a numerical simulation method were used to analyze the pressure drop of foam flow in the coiled tubing spiral section, and the calculated pressure drop was compared with the simulated pressure drop. For foam flow in the straight section, as the influences of acceleration pressure drop and actual velocity profile were considered, the simulated pressure drop is higher than the calculated pressure drop. For foam flow in the spiral section, due to the compressibility, the foam physical properties change with pressure. Therefore, at different outlet pressures, the velocity profile and density profile are different at the same spot. Centrifugal force makes the velocity profile unsymmetrical. Outlet pressure, gas injection rate, and curvature have significant influence on pressure drop. During the hydraulics design for coiled tubing drilling with foam, the foam injection pressure should be as high as possible to decrease the pressure drop of foam flow in the spiral section.
Numerical Simulation of Heat and Moisture Transfer of Wall with Insulation
Authors: Wei Ming , Wang Bo , Liu Shunbo 
Published: August 2019

Abstract
This paper improves the heat-moisture coupling transfer model with temperature and relative humidity as the driving force, and regards the effective thermal conductivity and vapor permeability of the wall material as a function of temperature and relative humidity. The latent heat generated by steam diffusion was introduced into the model and the model was numerically calculated using the finite element software COMSOL Multiphysics. The calculation results show that as the thickness of the insulation increases, the heat transfer and moisture transfer inside the wall slow down. When the temperature gradient or the water vapor concentration gradient on both sides of the wall increases, the heat transfer rate will also increase. But they will gradually stabilize. After reaching a steady state, there will still be moisture and temperature transfer due to the existence of the gradient.
Experimental Study on the Effects of Pier Shape and Skew Angle on Pier Scour
Authors: Shahhosseini Mohammad , Yu Guoliang 
Published: August 2019

Abstract
Scouring around the bridge piers is one of the reasons for their instability, and in the absence of a suitable solution, it will eventually lead to the destruction of the structure. Therefore, studying the mechanism of scouring and effective parameters on its value is essential. In this study, using a laboratory model, this scouring phenomenon was investigated, and the effect of bridge pier shape and the skew angle between water flow and bridge pier on scouring were investigated. Experiments for four pier shapes, including a rhombus 30° inner-angle, rhombus 60° inner-angle, a cylindrical and an oblong, and three velocities include 0.191, 0.30 and 0.380 m/s, in two modes: parallel and skew-angles between stream and piers. The results show that the depth of scouring depends on the shape of the bridge pier and the angle of its placement in the flow. The best shape of the piers, the smallest scouring around it, is the rhombus 30, rhombus 60, oblong and cylindrical respectively. When the rust-shaped pier was placed in running water, in addition to less flow turbulence, the amount of scouring is also reduced. Also, due to the test with an angle between the stream and the bridge pier, the turbulence of the stream and scouring around the pier of the rhombus30 is lower than the other piers. The shape factor can be used as 1.0 for circular and oblong, and 0.9 for the shape of the rhombus 30 and the rhombus60. By analyzing the experiments, a suitable form for the bridge pier, a rhombus 30° inner-angle was proposed.
Characterization of exchange flows within pressure exchanger device by Lattice Boltzmann method
Authors: Shi Yao , Liu Qingcha , Zhao Yiding 
Published: August 2019

Abstract
Seawater reverse osmosis (SWRO) with pressure exchanger (PX) been used widely on the earth for desalination to produce fresh water. Mixing due to exchange flow is considered to be dominant. In this paper, full-depth exchange flow is numerically simulated by Palabos, an open source program based on Lattice Boltzmann Method. GIF pictures and data produced by Palabos are analyzed to figure out how exchange flow processes. The velocity of the current front U=0.45 √(g(1 − γ)H is obtained from analysis. The results from the simulation are consistent with the Benjamin’s energy-conserving theory very well for full-depth exchange flow.
Research on sliding hydrodynamic performance of flying boat
Authors: Wang Xiaoxiang , Wu Bin , Li Xinying , Huang Miao 
Published: August 2019

Abstract
The towing tank test of a scaled flying boat model is designed to obtain it’s resistance, heaving and pitching characteristics as the speed changes in the sliding progress; then based on the secondary development of fluent; the global moving mesh and VOF methods are applied in the simulation; the calculation gives the fluid field around the boat, especially the wake flow, and also the pressure distribution of boat step. the results compared to the experiment date prove that using this method to study the hydrodynamic performance of a flying boat is feasible and precise.
Experimental study on a solenoid valve-based generator for droplet generation
Authors: Wang Liping , Kong Weiliang , Liu Hong , Wang Fuxin 
Published: August 2019

Abstract
An on-demand droplet generator is developed based on a high-speed and 2-way solenoid valve and studied experimentally in this paper. It is found that the valve-based droplet generator has good controllability, repeatability and stability. Under a suitable applied pressure, a single droplet can be generated by opening the valve with a short voltage pulse. Besides, the droplet size can be conveniently controlled by the applied liquid pressure and pulse width of the control signal. The results show that the present device successes to avoid the limitation of an appropriate outlet pressure required at nozzle tip for most droplet generators in the literature and is capable of producing droplets in a wide size range for a fixed nozzle diameter.
CFD Simulation of Two-Phase Flows in Anaerobic Digester
Authors: Chen Jianyuan , Chen Anpeng , Shaw Jiunnhaur , Yeh Chewei , Chen Shingder 
Published: August 2019

Abstract
In recent years, the study of Anaerobic Digestion (AD) has become one of the important technologies in the development of biogas production as renewable energy source. It can reduce the emissions of greenhouse gases and improve management of solid wastes. The production of biogas is influenced by many parameters including temperature, mixing, pH and hydraulic retention time etc. In this study, the mathematical model and numerical simulation of the turbulent, two-phase flow of liquid and gas in a Anaerobic Digester were conducted by Computational Fluid Dynamics. The hydrodynamic behaviours of the gas-lift and mechanical mixing digesters were investigated, such as velocity field, dynamic viscosity and optimal mixing type.
Dynamic Analysis of Torsional Vibration of Reed Damper of Diesel Engine
Authors: Li Yong 
Published: August 2019

Abstract
During the operation of diesel engine, there are many kinds of vibration modes in its shafting motion. Now the main explanation is torsional vibration. This kind of vibration may lead to the increase of shaft wear, even the fatigue damage of the shaft system or the damage of the diesel engine. During the operation of spring shock absorber, its components shear oil film continuously and interact with lubricating oil, which affects the change of fluid damping of the shock absorber, so as to better select effective methods to cope with the change. The fluid-solid coupling method is used to simulate the effect of lubricating oil and analyze the vibration absorption performance of shock absorber. Therefore, choosing elastic damped spring damper can respond to fluid-structure coupling analysis, through dynamic analysis, reduce torsional vibration of shafting and improve the safety of ship navigation, which has important significance and value.