bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluating a predictive model of student performance in introductory calculus-based physics
Authors: Greene M , Lopez R 
Published: August 2019

Abstract
Various factors are known to correlate with performance in physics and other STEM courses. In this study, we report on students’ performance in an introductory calculus-based physics course at the university level and correlate their performance (as measured by final grade) with a variety of measures of academic and cognitive ability. These measures include mathematical and English language ability (as measured by the SAT), incoming GPA, and spatial and scientific reasoning ability (as measured by the Mental Rotation Test and Classroom Test of Scientific Reasoning). We also consider the effect on student performance of factors such as employment status, and science and mathematics self-efficacy (as measured by a survey). In this study, we report the prediction efficiency of the ability of two multivariate linear models to predict student success in the course.
The Presence of Physics Education Research in the Curriculum of an Initial Teacher Education Programme
Authors: Jesus A C S , Nardi R 
Published: August 2019

AbstractThe objective of this study is to understand how a curriculum of an initial physics teacher education programme introduces elements of research in physics education for future teachers. This study is justified by the need to reduce the gap between what educational research outcomes says and what is practiced in the classroom, taking the initial teacher training as a possible way to bridge this gap. We present analysis of curricular documents of an initial teacher education programme in Brazil, mainly the Pedagogical Project and Teaching Plans of the subjects Methodology and Practice of Physics Teaching, and we based on Discourse Analysis as a theoretical-methodological framework. Analysis of the curricular documents of the programme indicates that there are several topics that are being studied by the researchers in physics education such as alternative conceptions, CTS relations and didactic laboratories, present in the curriculum. However, the various possible interpretations for teaching issues can provide different meanings between research outcomes, teacher training and physics teaching.
Potentially meaningful teaching unit on Cosmology in the vision of the teacher of fundamental and average education
Authors: Lacerda Caldas R , de Oliveira Siqueira A B 
Published: August 2019

Abstract
This research investigated the potentialities of the Meaningful Learning Theory (MLT) for the facilitation of the teaching of Modern and Contemporary Physics (MCP) content at the intermediate level. Privileging a qualitative approach, the work was based on the theoretical reference of the epistemology of teaching practice, on the teaching model of Gowin’s theory and on the principles of Ausubel’s Meaningful Learning theory for the elaboration of Potentially Meaningful Teaching Units. The entire study resulted in the elaboration of an Educational Product, constituted by the MLTs elaborated in the themes of Cosmology and Radioactivity. On-line questionnaires and interviews with physics teachers and activities used in MLTs were used as data collection instruments. Regarding the teaching of Cosmology and Radioactivity, the teachers suggested that they be taught through films, seminars and reading interdisciplinary texts. The analysis of answers by five teachers, regarding the efficiency and relevance of the strategy as a material to support the teaching in general, were positive. The teachers approved the potential of the material analyzed, activities, the instructions for execution, the time to plan and elaborate activities related to MCP, content not even emphasized in physics classes.
Augmented lectures: benefits of supporting physics teaching with the theatre
Authors: Giliberti M , Persano Adorno D , Pizzolato N , Battaglia O R , Fazio C 
Published: August 2019

Abstract
Young generations are less and less interested in studying STEM subjects. For this reason, numerous studies have strongly suggested a change in the methods scientific knowledge is developed in the learners, through the use of alternative and more creative strategies. In recent decades a strong interaction between scientific subjects and the arts has been established by means of theatre. The objective is to bring science to students and the public in ways that are engaging, instructive, artistic and, always, content-driven: the medium is the arts; the message is the joy of science. When we talk about Physics in a theatre show, are we only making a good dissemination or are we also transmitting contents and changing the nature of science view of the audience? In order to address this question, after the augmented lecture titled “There are no things inside things”, we invited the audience to answer both to a closed-answer survey about the performance and to an open-ended questionnaire focused on the theme “what is understanding?”, in terms of physics contents and NoS view. In this contribution, we analyze and discuss the answers provided by the people who have attended the augmented lecture. The analysis of the answers shows that the performance was appreciated as an example of showmanship in facing the wide-range cultural message of physics.
ESP Simulation Study on the DC Grounding Electrode in Chinese Shanbei Converter Station Based on ANSYS
Authors: Ma Chenglian , Sun Li , Zhao Shujian , Wang Letian , Zhang Li 
Published: August 2019

Abstract
When the UHVDC project was put into operation, the grounding current of DC grounding electrode may have a great influence on the transformer near the pole. The calculation of earth surface potential (ESP) distribution was a problem to be considered in the planning and design stage. In this paper, the calculation method of the current field of DC transmission grounding electrode was deduced. The grounding electrode project of Chinese North Shaanxi converter station was referred, and the layered model of 6 layers of ground soil was established. The potential distribution in the range of 0-100 km of the earth electrode was calculated by using ANSYS. The calculation results show that the distance between the ground electrode and the ground electrode decreases faster than that of the ground electrode. The distribution of earth surface potential within the range of 2 km of the earth electrode should be studied emphatically, and the potential distribution of the substations and power plants that have been built and planned has been calculated. The method presented in this paper could provide reference for the debugging of HVDC transmission monopole.
Economic Optimal Dispatch of Grid-connected Microgrid Based on Improved Genetic Algorithm
Authors: Sun Li , Zhao Shujian , Ma Chenglian , Chen Naixin , Yao Tianliang 
Published: August 2019

Abstract
Nowadays, the demand for energy is expanding, the fossil resources are on the verge of exhaustion, and the ecological environment is getting worse and worse. In this form, this paper studies the economic optimal dispatch of microgrid under the background of energy saving and emission reduction. Firstly, the mathematical model of microgrid composed of distributed power, energy storage devices and loads is established. Secondly, under the background of energy saving and emission reduction, the objective function of multi-objective optimal operation of microgrid is established considering both economic and environmental aspects. Finally, the improved Genetic Algorithm is used to solve the objective function. The results of optimization can reduce microgrid system generation cost.
Portable Solar-powered Membrane Distillation System to Solve Water and Energy Problems Simultaneously
Authors: Chafidz Achmad , Rahma Fadilla Noor , Nurkhamidah Siti , Al-Zahrani Saeed 
Published: August 2019

Abstract
With increasing human population, the demand for water as well as energy also increasing. This will lead to global water scarcity and energy crisis, due to limited freshwater resources and decreasing fossil fuel resources. The most potential solution to solve this water-energy problem is by using desalination technology powered by renewable energy like solar energy. This paper reports the design and development of a portable and stand-alone solar-driven desalination system. Due to portability, this system is expected to be transported to anywhere like remote areas. The system consists of three major parts, which are solar-thermal collector, solar photovoltaic (PV) panel, and Vacuum Multi-Effect Membrane Distillation (V-MEMD) unit as the main part of the system. In this paper, a small-scale operation test of the system was carried out and analyzed. The system run successfully for about 7 hours, which started at 09:00 AM. The feedwater used was brackish-water with conductivity of about 2500 μS/cm and the flowrate was maintained at 69 L/h. The system produced distillate/freshwater at average rate of 5.98 L/h. Whereas, the total distillate produced was approximately 34.8 L with conductivity of about Total Dissolved Solid (TDS) of 2.67 mg/L. The distillate flux of the current system was in the range of 3.2 – 5.2 L/m2.h.
Energy Optimization Dispatching of Microgrid in The Stand-alone Mode
Authors: Sun Li , Zhao Shujian , Ma Chenglian , Jiang Jing , Meng Yuanzhu , Yao Tianliang 
Published: August 2019

Abstract
A microgrid system in the stand-alone mode with photovoltaic, wind turbine, microturbine, fuel cell and energy storage unit is studied. Mathematical models of different distributed power supply and energy storage devices are established. The load demand of the system, the price of purchasing and selling electricity when interacting with the power grid and other constraints are considered. An economic model for optimizing stand-alone operation cost is established. According to the characteristics of the model, an improved genetic algorithm is selected to optimize the nonlinear system. The algorithm has better stability in solving the optimization problem of large state space dimension. The case study show that the proposed economic model is reasonable and the algorithm is effective.
Research of Unit Bidding Strategy and Earnings Analysis in the Peak Regulation Ancillary Service Market
Authors: Yan Cui-Hui , Yan Jinghua , Sun Zhen , Zhang Lin , Song Shaoqun 
Published: August 2019

Abstract
With the gradual development of electricity market reform, the peak load ancillary service market has been built in many regions of China. It is necessary to analyse the bidding strategies and earnings of thermal power units in different bidding modes and settlement modes. First of all, according to the cost of thermal power units, the cost of participating in peak ancillary services is studied. Then, based on the accurate prediction of the market clearing price in peak shaving, the bidding strategy and profit of thermal power units under the corresponding market rules are studied. Finally, considering the prediction error of the market clearing price in peak load regulation, the bidding price in peak regulation is taken as a random variable to study the optimal bidding strategy and the maximum expected return of thermal power units. The research results show that thermal power enterprises can improve their own profits by choosing the optimal strategy. Different bidding modes have little effect on the efficiency of market operation, while different settlement modes have obvious effect on the total market peak regulating cost and the peak regulating income of thermal power enterprises.
Decreasing the Sulfur Content of Crude Oil by Ultra-Sound and Activated Carbon Assisted Oxidative Method
Authors: Hameed Khlaif Tahseen , Salim Bded Asaad 
Published: August 2019

Abstract
There is a large amount of sulfur compound in crude oil, sulfur gases such us H2S for example are emitted and can affect the environment and finally can cause problems during the processing operation of crude oil. Therefore, in this study, a method for the removal of sulfur from crude oil using an ultrasound device has been proposed. This method is a combination of oxidative method and applying ultrasonic waves to achieve the allowable sulfur content in crude oil. Samples of crude oil have been taken that we got from an al-Najaf refinery to study the effect of three parameters (activated carbon weight, hydrogen peroxide volume, and acetic acid volume) at 50oC on the desulfurization process. the optimum result of desulfurization has been found to be (81.325%) at activated carbon amount of (9gm) with (H2O2/acetic acid)(40/30)ml.
Performance enhancement of trickle bed reactor for the removal of organic compounds from petroleum industrial wastewater
Authors: Al-Naimi S A , Al-Sudani F T , Al-Rawi G D A 
Published: August 2019

AbstractCatalyst Wet Air Oxidation of phenol Promoted with Hydrogen Peroxide (PP-CWAO) was studied experimentally in this work using a trickle bed reactor operating in both steady state and periodic operation (liquid flow modulation). The effect of cyclic parameters (cycle period and split) are investigated under the same conditions chosen on the basis of the steady state results for PP-CWAO. The results showed that the PP-CWAO of phenol are kinetically controlled for steady state operation. For periodic operation, the time average conversion enhancement is indeed quite considerable in liquid flow modulation as split is lowered from steady state cycle split (σ = 1) to a value of (σ = 0.5) and reached as much as 6.66 % over the steady state at cycle period (τp) = 15 sec.
Heavy metals concentration in the recent sediments along the sides of the road between Bangazi and Sirt Cities – Libya
Authors: Basi M A , Abbas K F , Al-Sharqawi M I 
Published: August 2019

Abstract
Heavy metals concentrations of Pb, Cd, Zn, Mn, Cu, Co, Ni, and Fe, have been studied in the recent sediments along the sides of the road between Bangazi and Sirt cities. The results indicate normal range of the concentrations, which reflect no pollution. Moreover, the study indicates the increase in concentrations of Pb, Cd, Zn, Mn, Cu, Co, and Ni, on the edges of both sides of the road. The increase in concentration of most heavy metals in the sediments at the edges of the road is most probably related to hydrocarbon’s exhaust of various vehicle.
Study the effect of organic promoters on thermodynamics behaviour for refrigerant gas clathrate hydrate
Authors: Talib Al Hemeri Shurooq , Sadeq Al Mukhtar Riyadh , Saadi Mohammed Mustafa 
Published: August 2019

Abstract
The present work consists of an experimental and theoretical investigation dealing with hydrate formation for the binary system (water+ refrigerant gas) and ternary systems (water+ refrigerant gas+ promoter) at constant initial conditions (pressure and temperature). Isochoric method (constant volume) search was used in current study to measure the formation data (pressure, temperature) for hydrate. Refrigerant R134a gas and different organic promoters such as benzene and cyclohexane were used in this study. For ternary systems at the different concentrations of promoters shifted hydrate formation data when benzene and cyclohexane decree pressure and increasing temperature. Many objective functions were obtained from kinetic models such as the amount of gas consumed (Δn), the growth rate (r (t)), and conversion of the water to hydrate. The gas consumed (Δn) of the binary system increased lead to increase in hydrate formation, also the hydrate growth rate (r(t)) and increase water conversion to hydrate. The gas consumed in the presence of cyclohexane was higher than at using benzene as a promoter. The experimental results show that the presence of different promoters in the ternary systems have an effect on thermodynamic promotion of refrigerant hydrates formation. The promotion effect increased with increasing the concentration of promoter in the select range. Also, the results manifested that benzene and cyclohexane had a clear effect in reducing the pressure and raising the temperature of the hydrate formation. The storage capacity was investigated. It has been noticed that the existence of the promoters in the hydrate formation system led to a slight increase in the storage capacity with maximum value about (78.66) V/V.
Evaluation of Petrophysical Properties Using Imaging Techniques
Authors: Ramadhan Ahmad A. , Al-Sudani Hussien I.Z. , Sarhan Kadhim Fadhil , Tariq Ayman , Lutfy Muhammed 
Published: August 2019

Abstract
The petrophysics science is concerned with the study and characterization of oil and gas reservoirs for the hydrocarbon potential availability and productivity through the quantitative of rock properties. Porosity is one of the most important property in petrophysics. Estimation of porosity values are classified into two techniques, direct and indirect methods. The direct method has been used to estimate the porosity from core analysis, because the well log records are considered as indirect technique, which depend on the measurments of the physical features related with the porosity values. In this study two methods are used to evaluate the porosity of carbonate reservoir. The first one has been applied to the well logging interpretation, while the second method uses imaging technique interpretation based on core slides. The result of the second method shows a more accurate results of porosity in comparison with first method. The porosity values are varied from 2% to 3% by using Neutron log, while the density and sonic logs recorded about 9%. The optical image results of the porosity are ranging from 6.2% to 19.1% at 40 X magnifications, and from 1.8% to 4.6% at 100X. The SEM image interpretation results are: 12.2%, 10.4, % 4.1%, 5.9% at 400X, 1.99KX, 5.01KX, and 10KX respectively. Finally, the results showed that accuracy of porosity values depends on the examined area of sample that the area of sample is changing with the magnification of microscopes types.
Study of different geostatistical methods to model formation porosity (Cast study of Zubair formation in Luhais oil field)
Authors: Al Musawi Jassim M. , Al Jawad Mohammed S. 
Published: August 2019

Abstract
This study is concerned with making comparison in using different geostatistical methods for porosity distribution of upper shale member - Zubair formation in Luhais oil field which was chosen to study.
Kriging, Gaussian random function simulation and sequential Gaussian simulation geostatistical methods were adopted in this study. After preparing all needed data which are contour map, well heads of 12 wells, well tops and porosity from CPI log. Petrel software 2009 was used for porosity distribution of mentioned formation in methods that are showed above. Comparisons were made among these three methods in order to choose the best one, the comparing criteria was according to different statistical information and variograms analysis of entered porosity which was scaled up and modeled. The best method gave porosity distribution in model closest to enter porosity that represent real porosity of Zubair formation.
The comparison proved that sequential Gaussian simulation is the best model of porosity distribution followed by Gaussian random function simulation and kriging methods respectively. Based on the results obtained, it was concluded that the distribution accuracy of the porosity or other petrophysics properties is one of the main factors that affect building correct geological model that represents the base of reservoir model and also pore volume (Oil reserve) value was affected by geostatistical methods variation.
Porosity and Permeability Calculation Using NMR Logging in an Iraqi Oil Field
Authors: Dhahir Abdulkadhim Marwah 
Published: August 2019

Abstract
This study aims of analysing the NMR data and extracting the petrophysical properties of a well in an Iraqi oil field, T2 analysis forms the basis of more complex analysis for the interpretation of NMR, including wettability analysis, facies discrimination and the identification of reservoir units from NMR data. T2 analysis can also be used to calculate porosity, calculate the geometric mean of the distribution, track the position of the modes (peaks of the distribution), and estimate fluid viscosity. NMR logging data has been used for an Iraqi oil field and interpreted to calculate PHIT, PHIE, BVI, CBW, FFI and K. In this current research the petrophysical properties have been calculated and the moveable fluid zone has been detected, where the porosity and permeability values are significant with a good value of FFI which represents the reflection of high value of T2.
Modeling of Petrophysical Properties and Reserve Estimation of Mishrif Formation-Garraf Oil Field
Authors: Abeed Ahmed T , Lazim Samaher A , Hamied Ramzy S 
Published: August 2019

Abstract
In this study a build-up a 3D geologic model both depend on the information of field and subsurface is a usual task in geologic studies including resource evaluation and hazard assessment. During this study a 3D geologic model for Mishrif Formation in Garraf oil field has been set-up by using petrel 2015 software system. Mishrif Formation represents the foremost important reservoir in Garraf oil field. Four vertical oil wells and one directional well were chosen in Garraf Oil Field so as to set-up structural and petrophysical models delineated by a 3D static geologic model in 3 dimensions. The structural closure is shifted from GA-3 well to GA-A1P well. Mishrif Formation was divided into 10 zones. Sequential Gaussian Simulation algorithm was used to build-up Petrophysical model (NTG, permeability, water saturation and porosity) for Mishrif Formation keeping with information analyses and also the results from modeling the units (M1.2, L1 and L1.2) are thought-about as prime quality reservoir units because of the high PHIE and low water saturation. Units (L2, L2.2, L2.3 and L2.4) are thought-about as poor reservoirs because of low PHIE and high water saturation, and non-reservoir units include (Top Mishrif, M1 and M2) thus, they represent cap units. Cross sections of petrophysical model were conducted to Illustrate the vertical and horizontal distribution of porosity, permeability, Net to gross and water saturation between wells within the field. This study calculated the reserves of the Mishrif formation of Garraf oilfield by petrel, that alter the issue that the reserves parameters are difficult to properly acquire when estimate complex reservoir’s reserves in terms of ancient volume technique.