bluuebunny/crossref_metadata_2025_split huggingface dataset:
Algodoo for online education: impulse and momentum activities
Authors: Çoban Atakan 
Published: January 2021

Abstract
During the periods of sudden transition to online education, the opportunity to make applications that might attract students’ attention to the course has decreased even more. Although this deficiency tried to be eliminated with videos and simulations, it was not possible to ensure the active participation of students in some cases. In this study, the Algodoo program, which can increase the efficiency of the teaching environment by ensuring active participation of students in online lessons and the applications that can be done about impulse and momentum, are explained in detail. A total of six different applications were carried out, one related to the subject of impulse, one related to the momentum, two related to the relationship between impulse and momentum change, and two related to momentum conservation. At the same time, while developing these applications, the adjustments made on the simulation and the reasons are explained in detail. In this way, both the introduction of the program and the sample application suggestion were presented. The values obtained as a result of the applications were calculated and compared both theoretically and on simulation in different ways. As a result, it has been observed that the values have internal consistency with each other and are also compatible with theoretical calculations. The Algodoo program, which allows many interactive applications and can be downloaded for free, is a program that can be used both in lecturing and evaluation processes in physics lessons during the online education process.
The magnetic field in the axis of an elliptic loop current
Authors: Romero-Abad David 
Published: January 2021

Abstract
The calculation of the magnetic field produced by a loop current using the Biot–Savart law is a very typical exercise in introductory university physics. However, the cases studied are limited, in most textbooks, only the circular arrangement is treated. In this article, we calculate the magnetic field of an elliptical loop current along an axis that passes through its centre. This calculation uses physical concepts and mathematical techniques that would be accessible to an average freshman student.
Comparison of weekly and daily online adaptation for head and neck intensity-modulated proton therapy
Authors: Bobić Mislav , Lalonde Arthur , Sharp Gregory C , Grassberger Clemens , Verburg Joost M , Winey Brian A , Lomax Antony J , Paganetti Harald 
Published: January 2021

Abstract
The high conformality of intensity-modulated proton therapy (IMPT) dose distributions causes treatment plans to be sensitive to geometrical changes during the course of a fractionated treatment. This can be addressed using adaptive proton therapy (APT). One important question in APT is the frequency of adaptations performed during a fractionated treatment, which is related to the question whether plan adaptation has to be done online or offline. The purpose of this work is to investigate the impact of weekly and daily online IMPT plan adaptation on the treatment quality for head and neck patients. A cohort of ten head and neck patients with daily acquired cone-beam CT (CBCT) images was evaluated retrospectively. Dose tracking of the IMPT treatment was performed for three scenarios: base plan with no adaptation (BP), weekly online adaptation (OAW), and daily online adaptation (OAD). Both adaptation schemes used an in-house developed online APT workflow, performing Monte Carlo dose calculations on scatter-corrected CBCTs. IMPT plan adaptation was achieved by only tuning the weights of a subset of beamlets, based on deformable image registration from the planning CT to each CBCT. Although OAD mitigated random delivery errors more effectively than OAW on a fraction per fraction basis, both OAW and OAD achieved the clinical goals for all ten patients, while BP failed for six cases. In the high-risk CTV, accumulated values of D
98% ranged between 97.15% and 99.73% of the prescription dose for OAD, with a median of 98.07%. For OAW, values between 95.02% and 99.26% were obtained, with a median of 97.61% of the prescription dose. Otherwise, the dose to most organs at risk was similar for all three scenarios. Globally, our results suggest that OAW could be used as an alternative approach to OAD for most patients in order to reduce the clinical workload.
Frequency-dependent optimal weighting approach for megavoltage multilayer imagers
Authors: Valencia Lozano Ingrid , Shi Mengying , Myronakis Marios , Baturin Paul , Fueglistaller Rony , Huber Pascal , Lehmann Mathias , Morf Daniel , Ferguson Dianne , Jacobson Matthew W , Harris Thomas , Berbeco Ross I , Williams Christopher L 
Published: January 2021

Abstract
Multi-layer imaging (MLI) devices improve the detective quantum efficiency (DQE) while maintaining the spatial resolution of conventional mega-voltage (MV) x-ray detectors for applications in radiotherapy. To date, only MLIs with identical detector layers have been explored. However, it may be possible to instead use different scintillation materials in each layer to improve the final image quality. To this end, we developed and validated a method for optimally combining the individual images from each layer of MLI devices that are built with heterogeneous layers. Two configurations were modeled within the GATE Monte Carlo package by stacking different layers of a terbium doped gadolinium oxysulfide Gd2O2S:Tb (GOS) phosphor and a LKH-5 glass scintillator. Detector response was characterized in terms of the modulation transfer function (MTF), normalized noise power spectrum (NNPS) and DQE. Spatial frequency-dependent weighting factors were then analytically derived for each layer such that the total DQE of the summed combination image would be maximized across all spatial modes. The final image is obtained as the weighted sum of the sub-images from each layer. Optimal weighting factors that maximize the DQE were found to be the quotient of MTF and NNPS of each layer in the heterogeneous MLI detector. Results validated the improvement of the DQE across the entire frequency domain. For the LKH-5 slab configuration, DQE(0) increases between 2%–3% (absolute), while the corresponding improvement for the LKH-5 pixelated configuration was 7%. The performance of the weighting method was quantitatively evaluated with respect to spatial resolution, contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) of simulated planar images of phantoms at 2.5 and 6 MV. The line pair phantom acquisition exhibited a twofold increase in CNR and SNR, however MTF was degraded at spatial frequencies greater than 0.2 lp mm−1. For the Las Vegas phantom, the weighting improved the CNR by around 30% depending on the contrast region while the SNR values are higher by a factor of 2.5. These results indicate that the imaging performance of MLI systems can be enhanced using the proposed frequency-dependent weighting scheme. The CNR and SNR of the weighted combined image are improved across all spatial scales independent of the detector combination or photon beam energy.
Modeling and analyzing temperature-dependent parameters of Ni/β-Ga2O3 Schottky barrier diode deposited by confined magnetic field-based sputtering
Authors: Labed Madani , Sengouga Nouredine , Labed Mohamed , Meftah Afak , Kyoung Sinsu , Kim Hojoong , Rim You Seung 
Published: January 2021

Abstract
In this work, the temperature-dependent parameters of Ni/β-Ga2O3 Schottky barrier diode (SBD) were analyzed and modeled. The simulation is to elucidate the physical phenomenon behind this temperature dependence. At room temperature, the deviation of SBD parameters from the ideal case is due to the Schottky barrier height (

ϕ

B

)

inhomogeneity. A model is developed for this inhomogeneity in which an interfacial defected layer (IDL) is formed. Defects (extrinsic states) are related to plasma and Ar atom bombardment used in the confined magnetic field-based sputtering to realize the Ni Schottky contact diffusion in β-Ga2O3. Ni diffuses, upon annealing, to compensate defects in this IDL. It was found that the Schottky barrier height (

ϕ

B

) and threshold voltage

V

Th

decrease with increasing temperature. This decrease is related to intrinsic and extrinsic states (plasma and Ar bombardment). However, the ideality factor (η) increases which is related to the series resistance (R
S) increase. The increase is related to the interfacial layer and nickel resistance increase with increasing temperature.
The Validity of Hypothetical Learning Trajectory Based on Realistic Mathematic Education on Function Topics for Grade X Senior High School
Authors: Mardiah N , Armiati  , Permana D , Yerizon  , Arnawa I M 
Published: January 2021

Abstract
The tendency of teachers to teach functions mechanistically causes several problems in learning. Students are less interested and less motivated in learning mathematics, especially for the function topic. This study discusses the validity of the hypothetical learning trajectory on the topic of the function of grade X in Senior High School. The development model was the Plomp model, but in this study it was only up to the preliminary research stage. Based on the results of interviews with mathematics teachers at Senior High School4 and Senior High School 11 in Solok Selatan, it can be concluded that in the learning process, teachers only relied on textbooks, so that learning was less effective and the material in the textbook was still non conceptual and less related to the real world of students so that students found it difficult to understand the material but rather to memorize the material.
Analysis of Student’s Satisfaction to Academic Service in FMIPA Universitas Negeri Padang
Authors: Amalita N , Fitria D , Arnellis  
Published: January 2021

Abstract
It paper discuss about student’s satisfaction to academic services in FMIPA. It conclude facility and infrastructure, lecturer and education staff, and also student service. We use primer data from around 308 students. Questionnaire are arranged depend on tangibles, reliability, responsiveness, assurance and empathy. Based in data analysis, we conclude that all students less satisfied to the academic services in FMIPA. But, depend on analysis for each item, there are some points we have to increase, like lack of parking area, toilet, and religion facility for students which is prepared by faculty. It can be follow-up by faculty.
Teachers’ perspective of algebra learning in junior high school
Authors: Mukhni M , Mirna M , Khairani K 
Published: January 2021

Abstract
Teaching algebra in junior high school has its own difficulty. Algebra topic, such as using the variable, is introduced in the seventh grade of junior high school. Teachers must change students' ways of thinking from arithmetic thinking to algebraic thinking. The aim of this study is to know the teacher's perspective of algebra learning, especially about the number topic, in junior high school. The instrument was an open questionnaire, and it was given to 26 mathematics teachers at junior high school in Padang Pariaman region. The analysis used a descriptive approach. The result of the analysis shows that 18 teachers (69%) use media in learning mathematics, and most of them use media manipulative. There is no teacher using computer base media learning. Teachers find problems in algebra learning, such as students do not understand the type of number and the order of operations, which is happened because of misconception in mathematics.
Portofolio Optimization Through MPT on any Economic Situation on Indonesian Stock Exchange (2010-2020)
Authors: Rosha M , Arnellis  
Published: January 2021

Abstract
Modern portfolio theory told us that investors are tend to optimize the expected return of investment subject to a target of risk perception. In the real world, risks are depend on may factors, such as systematic risk (market risk and macroeconomics risk which can not be controlled to diversification) and non-systematic risk (specific company risk which can not be controlled through diversification). Applying Security Market Line Approach, constrained maximization and considering changes in economic situation between 2010-2020, we found that Modern Portfolio Theory can improve portfolio performance when limited impact is spotted on minimizing systematic risk of portfolio.
On Locating Chromatic Number of Disconnected Graph with Path, Cycle, Stars or Double Stars as its Components
Authors: Welyyanti D , Putri S R , Azhari M , Lestari R 
Published: January 2021

Abstract
Concept of the locating-chromatic number of graphs is introduced firstly by Chartrand et al. in 2002. In this concept only limited for connected graphs. In 2004, Welyyanti et al. generalized the concept and notion of the locating-chromatic number of a graph such that it can be applied for a disconnected graph. In this paper, we determine the locating-chromatic number for disconnected graphs with path, stars, cycle, or double stars as it's components.
The development of mathematics learning tools based on number heads together model to improve mathematical problem-solving skills of grade vii junior high school students
Authors: Lestari A , Permana D , Musdi E , Arnawa I M 
Published: January 2021

Abstract
This study aims to produce a valid and effective learning tool that is impactful towards students’ mathematical problem solving ability by using number heads together type cooperative learning model. The study developed both lesson plan ((known as RPP) and students' worksheets (known as LKPD) by using the Plomp development model. The research focuses on testing the effectiveness of the learning tool. The instruments used in this study are validation sheets and problem-solving skills tests. The result of the survey shows that RPP and LKPD were valid and effective.
Research on Multi-feature and Machine Learning Hierarchical Pedestrian Detection Method Based on Deep Learning
Authors: Hao Yitong 
Published: January 2021

Abstract
With the rapid development of science and technology, computers have become an important way for people to obtain information. As an important means of transmitting visual information, image plays a very important role. Pedestrian detection is a key research field of machine vision and a key technology in intelligent video surveillance and intelligent transportation system. Pedestrian detection is the basis and premise of pedestrian tracking, behavior analysis, gait analysis and pedestrian identification, and a good pedestrian detection algorithm can provide strong support and guarantee for the latter. Pedestrian detection is not an independent problem, it is closely related to video pedestrian tracking, human behavior recognition and pedestrian identification. The method of machine learning is to let the program have the ability of learning. Through continuous training and iteration, the parameters of the model are optimized. Deep learning can give full play to the speed and rationality of the machine and improve the accuracy of pedestrian detection.
A Specific Duration and High-energy Sine Wave Model to Reflect the Awaking and Falling Asleep Moments of Human
Authors: Yao Rentian , Li Yinsheng , Zheng Wei 
Published: January 2021

Abstract
The process of falling asleep is complicated. Is there a mutation between sleep state and waking state? This paper applied a new specific duration and high-energy sine wave (SDHE) model based on single-channel brainwave to study this problem. The falling asleep moment and awaking moment could be identified through the SDHE. The closest research is AASM criterion. 30 seconds multi-channel brainwave as a frame was used to score the human sleep stage in the criterion. In the Dreams database used in this paper, an expert did the sleep classification of the 20 test subjects according to the AASM criterion. The switching step between waking stage and other sleep stages provided a basis for this paper. Within one minute of the time difference, the Cohen’s Kappa consistency of the discriminant result of the model and the expert was 0.58. In view of the strong and clear law of the SDHE, this paper would have more promising applications and significance in the signal processing of brainwave.
Investigation of the Effect of Parameters on the Tightness
Authors: Du Peng , Zhang Wei , Wang Yongyan , Xie Zonghua , Jiang Qinglei , Tuo Jianzhi 
Published: January 2021

AbstractThe Center Composite Design (CCD) is built as a surrogate computationally expensive numerical simulations to improve the efficiency of the optimization design of metallic gas-ket. The optimization of important parameters such as wavy height, top flange thickness and gasket thickness is the goal of optimization by the CCD. Higher gasket thickness, wavy height and top flange thickness are beneficial to the improvement of sealing reliability. By comparing the optimization results with the finite element analysis results and test results, the results show that the coincidence is high and the design efficiency is greatly improved.
Research on the Weighted Regression Method of Artillery Trajectory Fitting Computation
Authors: Pan Zhang , Jiwen Liang , Pingjian Tang , Wei Chen 
Published: January 2021

Abstract
In order to improve the precision of the heteroscedastic artillery firing table, a fitting computation method for artillery firing table compilation without the assumption of homologous variance is proposed in the paper. The principle of the method is to elevate the regression effect of heteroscedasticity model with using appropriate weights. First, a reasonable method to estimate the variance of disturbance term is explored. On this basis, the variance function of disturbance term is fitted by polynomial basis and B-spline basis respectively. Finally, weighted B-spline regression was performed on the heteroscedasticity model with the variance function as the weight. This method does not need to ignore the existence of heteroscedasticity, nor is it limited by the general assumption in the past. It has positive significance to reflect the operational performance of the new weapon system objectively which is still in the stage of scientific research and design finalization. In addition, the method can be applied in both homoscedastic and heteroscedastic populations.
A multi-objective programming model based on the relative deviation
Authors: Wu Xinlin , Xu Min 
Published: January 2021

Abstract
Decision makers are often faced with the achievement of multiple goals in real life. The multi-objective programming model based on priority factors is an effective mathematical model to deal with multiple objectives, but it has some defects. In this paper, the concept of the relative deviation is introduced to deal with the defects of the multi-objective programming model based on priority factors, and the multi-objective programming model based on the relative deviation is proposed. A case study of portfolio decisions is given to illustrate the model. Results show that the model in this paper has more advantages than the traditional model based on priority factors.
Off-line programming of robot on laser cleaning for large complex components
Authors: Shuo Jin , Yuan Ren , Qingzeng Ma , Hailong Ge , Wenlong Li , Wei Cheng 
Published: January 2021

Abstract
Laser cleaning path planning is great for significance to the cleaning effect of component surface. In view of the fact that the cleaning head must keep a fixed focal length with the workpiece surface and keep a vertical angle with the workpiece surface at all times in the laser cleaning process, this paper introduces the numerical model of large components into the general off-line programming software, and according to the relevant laser cleaning process and setting specific parameters in the software, obtains the automatically planned machine. The human trajectory program is introduced into the robot to realize the surface cleaning of large and complex components. Finally, according to the actual cleaning effect in the field, the laser focal length deviation is controlled within ± 2mm, and the application of off-line programming of industrial robots in complex surfaces is summarized and prospected.
Application and Practice of Teaching Methods of Mathematics Information in Higher Vocational Education
Authors: Song Yuxia 
Published: January 2021

Abstract
Since 2019, in response to the requirements of the 2019 government work report, higher vocational colleges have implemented an expansion of 1 million people. Higher vocational mathematics teaching exists and faces new problems and challenges. This article briefly introduces some informatization teaching tools and platforms. On this basis, a reasonable informatization teaching plan is formulated, and teaching materials are integrated and optimized. The specific application and practice of informatization teaching are carried out in the teaching classroom, and an effective feedback mechanism is proposed. The results have greater sharing and promotion value. Eventually realize the goal of training high-level, high-quality and high-skilled talents.
Integrated optimization Control Strategy of DAB Based on DPS and Adaptive Genetic Algorithm
Authors: Deng Qin Rui , He Ying Jie , Lei Chao , Liu Jin Jun 
Published: January 2021

Abstract
In order to comprehensively consider the energy transmission efficiency of the isolated Dual-Active-Bridge (DAB) DC-DC converter, this paper proposes a control method that maximizes the power transmission efficiency of the whole converter and optimizes the stress of the switching device by using the dual-phase-shifting control mode under the premise of simultaneously considering current stress, back-flow power and power loss. Firstly, we compare and analyze the advantages and disadvantages of DPS, SPS and TPS, and finally determine the control method using DPS. Then analyze and compare the basic principles of the traditional current stress optimization target control method and the comprehensive efficiency optimal control method proposed in this paper. We compared the working mode analysis with the stability, current stress and application range of soft-switching. The adaptive genetic algorithm is used to optimize the two duty ratio degrees of freedom of the control strategy, and the optimal duty ratio corresponding to the objective function is obtained. Finally, the correctness of the control method and the superiority of the power transmission efficiency are proved by simulation and experimental comparison.
Research on Optimization Method of Multi-regional Power Grid Investment Scale
Authors: Liu Zifa , Peng Dong , Yu Puyang , Li Hui , Liu Hongyang 
Published: January 2021

Abstract
Optimizing the scale of investment in multi-regional power grids is the basis for ensuring the benefits of power companies and can meet the urgent needs of power grid development. This article first takes the historical benefits of power grids, planning benefits, grid scale and development needs as indicators to establish a multi-regional grid investment scale optimization indicator system. Then this article establishes a multi-regional grid investment scale optimization model. According to the historical benefits of the region and the grid scale, the initial distribution model of the grid investment scale was established; the grid investment scale revised model was established according to the planning benefits and development needs. Finally, an example is used to verify the effectiveness and feasibility of the method proposed in this paper.