bluuebunny/crossref_metadata_2025_split huggingface dataset:
Boat in the pool – lab work
Authors: Dvořáková I 
Published: August 2019

Abstract
This article describes a non-traditional lab focused on applying Archimedes’ principle in a situation that is, for students, new and unusual. Two main interconnected features of this lab are important. Firstly, it is not a “standard” lab experiment in which students are instructed to measure something and then to interpret results. Here, a very important element is prediction. Students have to predict the result first, calculate it using Archimedes’ principle, and only then do the measurement. Secondly, it is not the teacher who tells students whether their calculation is right or wrong, it is the experiment itself. This article presents the lab work itself (instructions and results), some methodological comments, and my experience in school.
Experiments and representations in quantum physics: teaching module on the photoelectric effect and the Franck-Hertz experiment
Authors: Ravaioli G 
Published: August 2019

Abstract
A teaching module, centered on the photoelectric effect and the Franck-Hertz experiment, was designed for upper secondary school students. The activities have been built upon three design principles, brought out from an analysis of the current research literature about laboratories, learning/teaching quantum physics and representations in physics education.
Meaningful student involvement. Students as “researchers”: a physics laboratory experience from space to microworld
Authors: Bertelli S , Centioni R , Scerbo F 
Published: August 2019

Abstract
Teaching physics and technology is a challenging, rewarding and exciting arena where teachers share the fascinating concepts of physics and technology evolution in a room full of young and inquisitive minds. Every day teaching experience confirms that Science learning motivation is correlated to real world applications. According to the last PISA-OECD survey, the performance of Italian students in STEM is below the OECD average. In the last years the Italian Ministry of Education, University and Research (MIUR) has been active in promoting a wide plan to improve STEM learning. These actions strongly supported the connections and collaborations between high schools, universities and research centers. In this framework, the Frascati National Laboratories (LNF) play a very important role in science dissemination through a rich program of physics education activities addressed to Italian teachers and students from all the world. The main idea is that meaningful involvement of students can take the form of engaging students as researchers. In this article the LNF activities for schools are presented with a focus on a case study of a work-related learning program attended by seventeen students of the high school “Liceo Siciliani” from Catanzaro (Italy) in February/March 2017. The students had the possibility to participate in two different experiences related to particle physics and nanotechnology. The project concerning particle physics will have a follow up, since the school “Liceo Siciliani” proposed an experiment on cosmic rays that will take place in the Calabria region, based on the experimental setup the students studied and used at LNF.
Using a large amplitude pendulum in a learning cycle strategy
Authors: González y Hernández A 
Published: August 2019

Abstract
Experiments with a damped simple pendulum were carried out and modelled for large amplitude motion with physics students in a mechanics laboratory course of the first year of the university. The equation of motion used for this pendulum was the equation of a damped pendulum where the simplification for small angles was avoided. In this investigation, the damping of this pendulum was assumed to be proportional and opposite to its velocity. This hypothesis was verified experimentally and the constant of damping was measured from the experimental data. This constant was introduced in the equation of motion of the pendulum to be solved by a numerical method. The comparison made between the numerical solution and experimental data was successful, giving students confidence in the strategy followed. With the support of the teacher students modelled empirically the period of the pendulum as a quadratic function of its amplitude and made good predictions of the behavior of the pendulum for other amplitudes by using the numerical solution. On completion of the course, in a revision of the students’ reports, it was possible to propose an empirical equation as an analytical solution for this pendulum, an important result of the learning cycle carried out in the study of the pendulum. In this process of teaching, students developed scientific skills that were evaluated and both students and teachers were able to build new knowledge about a pendulum with large amplitude.
Metaphors and analogies proposed by perspective primary teachers to support the exploration of magnetic phenomena.
Authors: Bozzo G , Daffara C , Michelini M , Monti F , Vercellati S 
Published: August 2019

Abstract
Analogies and Metaphors play an important role in primary science education to correlate abstract aspects and lived experiences, providing concrete meanings for pupils. They represent important educational tools that can help young pupils to approach towards abstract physics concepts like those related to magnetic phenomena. The significant presence of these phenomena in the world of 21th century allows pupils to explore and to familiarize with them starting from their childhood. These daily experiences offer pupils the opportunity to build spontaneously their own interpretative models about magnetic phenomena that influence also their future learning processes during the school careers. Recent educational researches have shown how pupils are able to master the interpretation of magnetic phenomena if those aspects are activated in the context of Conceptual Laboratories of Operative Exploration (CLOE). In order to improve the competencies of Prospective Primary Teacher (PPT) students related to the use of analogies and metaphors in education, a specific module of formative intervention was developed and proposed involving 92 PPT students enrolled at the University of Udine and 67 PPT students at the University of Verona. Initially, an overview of a well-experimented learning path was proposed to the involved PPT students and then they had the opportunity to try experimentally the proposed activities. After that, they discussed in small groups how to face magnetic phenomena with primary pupils with the use of analogies and metaphors. Finally, each PPT student was asked to produce an individual proposal that was shared within the small groups, commented and, finally, individually revised. In this paper, we present a preliminary analysis of the analogies and metaphors through which PPT students would introduce the magnetic phenomena observed in the GEI exhibition to primary school pupils.
Quebec children and elementary pre-service teacher’s conceptions of force and motion
Authors: Métioui A , Trudel L 
Published: August 2019

Abstract
The analysis of the data of the paper questionnaire that we distributed to fifty-eight (58) children and 85 pre-service teachers of elementary education from Quebec in Canada demonstrates that most of their conceptions of force and motion are incompatible with established scientific theory. They look like those developed in the setting of the pre-Newtonians Physics such as the Aristotelian view and the 14th-century Impetus theory by Buridan. Most of the misconceptions identified are: the movement requires the continuous application of force; in the absence of a force, the objects are to be at rest; if an object is not moving, there is no force acting on it. The results were analyzed in the light of previous research on students’ conceptions of motion and force.
The Augmented Laboratory – 3D, Multiple Object Tracking
Authors: Rosi T , Onorato P , Oss S 
Published: August 2019

Abstract
We discuss the three dimensional, multiple object tracking capabilities of the “Augmented Laboratory”, a custom hardware and software setup we created for this purpose. Overall it proves to be a powerful and useful educational tool, not only allowing to use tracking in many more experiments with respect to traditional video tracking, but also creating 3D visualizations of the experiments themselves and of the tracking results. The setup was also tested with a group of aspiring teachers and their comments were here discussed.
Three years evaluation of a teaching learning sequence on rolling motion based on a blended learning environment
Authors: Onorato P , Malgieri M , De Ambrosis A 
Published: August 2019

Abstract
As highlighted by research, students have difficulty in understanding the physics of rolling motion and the role that sliding friction forces have in it. Physics courses at high school and introductory university level do not usually handle the subject with the attention it deserves. Textbooks often only show particular rolling examples instead of providing a general treatment of the underlying physics. Therefore, students can develop misunderstandings that lead to errors when approaching general problems. In 2014 we have designed a teaching learning sequence (TLS) rooted in previous research about student conceptions, centred on the role of friction in different cases of rolling. A series of experiments based on video analysis integrated with interactive simulations were used to emphasize key concepts and to motivate students in their exploration of the subject. The activity sequence was designed for undergraduate students or advanced high school classes. In this paper we report novel results from three years of testing and refining the teaching sequence at both the Universities of Pavia and Trento.
The time in science: an interdisciplinary laboratorial approach
Authors: Montalbano V , Castellini A , Donati A , Marchini D , Mariotti E , Mariotti M A , Porri A , Rossi B , Severi A , Sirigu M , Veronesi S 
Published: August 2019

Abstract
In order to promote problem-based and active learning in the physics laboratory, we designed a flipped classroom focused on the Franck-Hertz experiment. The flipped classroom approach moves course content from the classroom to homework and uses class time for engaging activities and problem solving. This constructivist approach to teaching is an effective means of student-centred collaboration and it can promote active learning, enhance critical thinking and obtain the maximum use of student-faculty time together. We report preliminary results of the flipped classroom approach to a laboratory and how it worked in the context of a small group of students in a physics course.
Assessment of problem solving activity on wave physics in secondary school
Authors: Minozzi F , Marzoli I 
Published: August 2019

Abstract
Italian secondary school students struggle with understanding wave-like phenomena. Many research-based materials are available on the topic, but their applicability is often limited by the constraints of actual school settings. We developed a set of conceptual problems on wave phenomena and tested them in classroom within a design-based research framework. We present the preliminary results of an on-going work that aims at providing teachers with high-quality versatile materials, along with testing our hypotheses on the learning processes.
Training teachers to use playgrounds in physics teaching
Authors: Pendrill A-M 
Published: August 2019

Abstract
Climbing racks, carousels, swings and slides can be used for many experiments and demonstrations that offer suprising results, often challenging students’ understanding of motion. This paper describes activities used in professional development workshops for teachers on the use of playgrounds in physics teaching. Toys and other simple equipment complement the experience of the body. In addition, smartphones can be used both for documentation and measurements. The activities emphasize how playground experiments can connect very concrete experiences of acceleration and force to textbook examples and fundamental physical principles.
Wondering with physics: engage public and teachers in science communication
Authors: Montalbano V , D’Onghia A M , Giambolini M , Montorzi R , Rossi B , Sirigu M 
Published: August 2019

Abstract
The European Researchers’ Night takes place every year simultaneously in many cities all over Europe and beyond. Researchers and teachers designed and implemented together a series of inquiry-based activities to bring people closer to physics. The enthusiast answer from participants suggests that these activities can be easily utilized with students for enhance their motivation. Moreover, the close collaboration between university and secondary school teachers is an opportunity for promoting the professional development on topics, like resonance or birefringence, sometimes very far from teaching practice.
Research on Influence of Converter Transformer Grouping and Receiving End Power Grid Structure on Converter Transformer DC bias
Authors: Ma Chenglian , Sun Li , Zhao Shujian , Liu Lianguang 
Published: August 2019

Abstract
When ±800kV UHVDC project was put into operation, DC bias problem can not be ignored. In this paper, a calculation model for DC bias current is established based on Xiluodu-Zhexi UHVDC project data. Converter transformer grouping and receiving end power grid structure are considered. The converter transformer DC bias current is calculated by node voltage method. The influence of different converter transformer grouping modes, distance between grounding electrode and substation, and the feeder length and the number of feeder loop are analysed. The results show that, single-phase converter transformer bias current is maximum with full load and 6 converter transformers under 1/2 monopole earth mode. And bias current level of converter can be reduced in planning and designing.
Research on the Method of Reducing Transformer DCBC Considering Converter Transformer Grouping and Receiving End Power Grid Structure
Authors: Ma Chenglian , Sun Li , Zhao Shujian , Liu Lianguang 
Published: August 2019

Abstract
Based on the study of the influence of converter marshalling and receiving grid structure on the DC bias current (DCBC), DCBC levels of typical connection structures between converter station and its adjacent substations is analysed in this paper. Then DCBC levels of converter stations and AC substations under different connection modes of substations in AC power network are analysed. The measures to reduce DCBC of converter transformer and AC transformer considering various factors are put forward. A method to reduce DCBC of converter transformer and transformer considering converter transformer grouping and receiving end power grid structure is proposed. The measures of restraining DCBC are analysed from the aspects of operation mode selection, grounding pole location, power grid structure planning and design. Suggestions are put forward for the treatment of DCBC in the planning and design stage.
Analysis of Reactive Power Demand Based on Voltage-Reactive Power Correlation
Authors: Hu Zhen , Zuo Jian , Chen Daojun , Cui Ting , Wang Ding 
Published: August 2019

AbstractThe inaccuracy of reactive power demand analysis in practical power system often leads to the problem of low voltage stability margin. In this paper, the analysis method of voltage-reactive power correlation is proposed, which is used to solve the inaccuracy of reactive power demand analysis. The proposed method can quickly analyze the reactive power demand of each region only according to the voltage stability margin index. The local reactive power compensation and the input reactive power on the system side are considered in the derivation of the voltage stability margin. Therefore, the proposed method accords with the practice of power system. The effectiveness of the proposed method is proved by a simple system.
Bias-dependent Access Resistances Extraction in 0.15 µm GaAs pHEMTs
Authors: Dang Ruirui , Yang Lijie , Song Chunyi , Xu Zhi Wei 
Published: August 2019

Abstract
Devices’ performance analysis and successful circuit design strongly depend on accurate large signal models. This, in turn, requires accurate small signal models. However, the reliable parasitic parameter extraction of GaAs pHEMT greatly influences the accuracy of small signal models, which also greatly influences the extraction of intrinsic elements. The access parasitic source and drain resistances, Rs
and Rd
, are associated with gate bias due to the two-dimensional charge control. In this work, we directly extract Rs
and Rd
from S-parameter measurements of the device under test (DUT) under strong inversion operating biases. The proposed method has been validated by simulation and on-wafer measurements. It shows better accuracy than existing arts in a frequency range of 0.5–40 GHz (0.5 GHz step). Furthermore, a 10-15 GHz GaAs pHEMT power amplifier (PA) is employed to further validate the developed method. The test results also validate the developed method.
Optimal Charging and Discharging Control of Plug-in Hybrid Electric Vehicles in a System-level Power Distribution Network
Authors: Li W , Lin Z Y , Yan G F 
Published: August 2019

Abstract
With the increasing popularity of plug-in hybrid electric vehicles (PHEVs), coordinated charging and discharging of PHEVs has become an important issue in power distribution networks. To this end, we employ a multi-objective optimization model to formulate the problem of coordinated charging and discharging of PHEVs, in which the objectives of load shifting and total costs minimization are both investigated under system’s technical constraints. A hierarchical optimal algorithm combining the iterative water-filling-based algorithm and the consensus-based method is proposed to solve the multi-objective optimization problem. It shows that the proposed algorithm not only enhances stable performance for the power load but also guarantees low-cost satisfaction for the vehicle owners in the system-level power distribution network integrating physical power network with information network together. Numerical simulations are presented to demonstrate the effectiveness of the proposed algorithm.
Harnessing of Wave Energy using Axially Magnetized Linear Generator with Data Logger using Gizduino Microcontroller
Authors: Cruz K , Dator F , Ong J , Bumanlag N , Pacis M C 
Published: August 2019

Abstract
This study focused on the design and construction of wave energy generation system. Wave energy is produced once the electric generators is placed parallel on the ocean surface and rides in different height of waves along the length of the device. It follows the concept of Faraday’s law of induction in the linear generator which an alternating current is induced in the loops of copper wire whenever the magnet slides back and forth through it. Using Axially magnetic type linear generator that will utilized the horizontal forces brought by the waves and placed on a waterproof floating boat with a data logger using microcontroller. The wave converter is deployed in a controlled and uncontrolled environment to observe the behaviour of the prototype and compared the measured parameters such as voltage, current, power, and energy at different time and wave height.
Optimized Algorithm for Muscular Diseases Recognition Based On Temporal Parameters Analysis and Correlation Coefficients
Authors: Mejia-Gonzalez E.A. , Lopez-Leyva J.A. , Estrada-Lechuga J. , Ponce-Camacho M.A. 
Published: August 2019

Abstract
In this paper, an optimized algorithm based on temporal parameters analysis and correlation coefficients is presented in order to perform muscular diseases recognition. Statistical information was measured of three classes signals (Healthy, Myopathy and Neuropathy conditions). The temporal parameters that were initially proposed (14) were optimized based on the correlation coefficients. Thus, only 9 parameters were selected for optimized the algorithm, and the time required for training and recognition is ≈ 0.2s and ≈ 4ms, respectively.
On Active and Reactive Power Control of Synchronous Generators: A Port-Hamiltonian Approach
Authors: Tajik Elham , Runolfsson Thordur 
Published: August 2019

Abstract
In this paper a general port-Hamiltonian model of a synchronous generator is presented and the effects of deviations and disturbances of the terminal signals on generator control laws are discussed. We discuss how control laws should be designed to minimize the effect of small variations in the generators terminal conditions, i.e. local control that does not have access or knowledge to a model of the rest of the system. For analysis purpose we present a linearized generator model and apply a full state feedback control consisting of both regulation of the generator flux and rotational dynamics.
Applying Selected Lost Circulation Materials to Study Lost Circulation of Azkand Formation in Khabaz Oil Field
Authors: Shibeeb Mazin J. , Alwasiti Asawer A. , Al_Zubaidi Nada S. 
Published: August 2019

Abstract
Managing lost circulation during drilling is a great challenge issue in naturally fractured or vugy formations. This situation becomes further complicated if there are gas or oil returns at the same formation or at a formation above it. The lost circulation problem happens in some of the northern Iraqi oil fields such as Khabaz oil field. Particulate lost circulation materials (LCM) have been used for many years to control lost circulation. However, these traditional LCMs are not efficiently applicable to cure sever to total losses, such as highly fractured formations and formation with large vugs. In this work, an experimental attempt was done to solve such problem in Khabaz oil field. The experiments were carried out using a closed loop circulation system that simulates the drilling fluid loss into formations. Five core plugs from Azkand formation of Khabaz oil field from different depths were used. The experiments were grouped into three, the first was done with the fresh-water-based drilling fluid to measure the severity of losses. The second, fresh-water-based drilling fluid was treated with traditional LCM (cotton seeds) to investigate how the severity of losses is affected by these materials. Adding polymer lost circulation material were the last sets to modify the drilling fluid rheological properties which prepare a medium within the lost circulation zone that increases the friction inside the losses paths to increase the LCMs (the polymer itself) sealing efficiency.
Activation Iraqi bentonite for using as drilling mud
Authors: Ibrahim A S , Al-Bidry M A 
Published: August 2019

Abstract
Drilling fluid is very important in drilling a well because it plays a vital role in all drilling operations. Drilling fluid should have popular properties that simplify safe and easy completion of the well. Because of the big cost of transporting and imported clays that used as drilling fluid, Iraqi benronite must be enhanced to use as drilling fluids due to its poor rheological and filtration properties, and stability. Iraqi bentonite has a limited usage in oil field because it is Ca- bentonite. The research has studied the usage of bentonite and its activation by NaoH in drilling fluid. The results show that Iraqi Ca-bentonite reaches to API specifications while the indirect activation includes activated Ca-bentonite by NaOH with different concentrations, HCL then NaOH without temperature and HCL then NaOH with temperature. Then activated bentonite is used as drilling mud. The results show that the indirect activated bentonite does not reach API specification, where XRF analysis show that an ion exchange between Ca and Na is not enough to convert Ca- bentonite to Na- bentonite.