bluuebunny/crossref_metadata_2025_split huggingface dataset:
Origin of hardening in spectra of cosmic ray nuclei at a few hundred GeV using AMS-02 data *
Authors: Niu Jia-Shu 
Published: January 2021

Abstract
Many experiments have confirmed spectral hardening at a few hundred GeV in the spectra of cosmic ray (CR) nuclei. Three different origins have been proposed: primary source acceleration, propagation, and the superposition of different kinds of sources. In this work, a broken power law has been employed to fit each of the spectra of cosmic ray nuclei from AMS-02 directly, for rigidities greater than 45 GeV. The fitting results of the break rigidity and the spectral index differences less than and greater than the break rigidity show complicated relationships among different nuclear species, which cannot be reproduced naturally by a simple primary source scenario or a propagation scenario. However, with a natural and simple assumption, the superposition of different kinds of sources could have the potential to explain the fitting results successfully. Spectra of CR nuclei from a single future experiment, such as DAMPE, will provide us the opportunity to do cross checks and reveal the properties of the different kinds of sources.
Experiment and simulation of ELM in NBI heated plasma on EAST tokamak
Authors: Geng K.N. , Tang T.F. , Kong D.F. , Zhang S.B. , Zhang T. , Huang C.B. , Wu M.Q. , Jiang D. , Lyu B. , Wang L. , Gao W. , Liu Z.X. , Liu A.D. , Duan Y.M. , Zhang L. , Jie Y.X. , Zang Q. , Zhu X. , Hao B.L. , Wang K. , Lin X.D. , Huang J.J. , Wan Y.X. , Gao X. 
Published: January 2021

Abstract
By scanning toroidal rotation with a combination of co- and counter-current direction neutral beam injection (NBI) on the Experimental Advanced Superconducting Tokamak, it is found the size of edge localized mode (ELM) decreases with increasing toroidal rotation in counter-current direction. The synergistic effect of plasma rotation and collisionality on ELM behavior is also studied by statistical analysis. Three-field module in BOUT++ framework is employed to study the impacts of toroidal rotation/E × B flow shear on ELM behaviors. The BOUT++ simulation results show that both Co- and Ctr-NBI induced net flow have stabilization effects on the peeling-ballooning modes, especially for counter NBI case, high-n ballooning mode can be totally stabilized. With larger E × B shear, the mode number of most unstable mode downshifts in the counter NBI case, with larger E × B shear, the mode number of most downshifts in the counter NBI case, correlated with reduced ELM size.
The Development of Learning Design for Polyhedron Based On Realistic Mathematic Education for Grade VII of Junior High School Students
Authors: Prestiani V , Irwan  , Arnawa I M 
Published: January 2021

Abstract
The flow of teaching mathematics on the topic of Polyhedron all this time emphasizes memorization of formulas and the provision of exercises to students which are still teacher-centered. Learning design is needed to facilitate students to actively participate in building the concept of building a flat-sided class room in grade VIII of Junior High School based on Realistic Mathematic Education using the learning flow in the form of Hypothetical Learning Trajectory and implementation products in the form of teacher books and student books. This type of research was development research that combines two types of research design, namely the Plomp and Gravemeijer and Cobb models which consist of three phases: preliminary research, development or prototyping and assessment phases. This research was limited to preliminary research. Teacher interview guidelines, student interview guidelines, field notes, preliminary test questions for students' mathematical reasoning abilities are used as instruments. From this preliminary research phase, it could be concluded as follows: (1) teachers are guided by printed books owned by teachers and students, which have not facilitated students to develop concepts through meaningful learning activities, (2) teachers also had not designed learning paths which was appropriate for teaching a mathematical topic, (3) the mathematical reasoning ability of students was not optimal, (4) the preparation of the learning flow was in accordance with the results of curriculum analysis.
The Role of Mathematics Anxiety and Mathematical Problem-Solving Skill
Authors: Rusyda N A , Suherman  , Dwina F , Manda T G , Rusdinal R 
Published: January 2021

Abstract
The purpose of this research is to analyze the correlation between mathematics anxiety and mathematical problem-solving skill. The data was collected by using a mathematics anxiety questionnaire and a problem-solving test. There were seven questions for the test of mathematical problem-solving and 25 questions for the mathematics anxiety questionnaire. The questionnaire was arranged by using the Likert Scale. The data were analyzed using the Pearson correlation formula. The population is the students in the calculus class. The samples are 200 students that were chosen by using a purposive random sampling technique. The results showed that there was a negative correlation between mathematics anxiety and mathematical problem-solving.
The Effect of Problem Based Module for Sampling Technique Courses Toward College Student Problem Solving Behaviour; Case Study in Indonesia
Authors: Harisman Y , Sovia A , Rahima  
Published: January 2021

Abstract
This study aims to look at the effectiveness of problem-based modules in lectures on Sampling Techniques toward problem-solving behavior. A module can also be used by using an e-learning platform if the lecturer cannot face-to-face because the modules designed can be used independently by college students because they contain material, examples, guided exercises, independent exercises, and answer keys. The subjects of this study were 26 college students from one of the private universities in Indonesia. The study used a One-Shot Case Study design. Data collection is done through a final Problem-Solving test, open interview, video analysis. Data were analyzed using a t-test and problem-solving behavior rubric. Based on the results of the study concluded that was the use of the Sampling Technique module in lectures affected college student problem-solving behavior. This means that the problem-based sampling technique module is effectively used in studies.
Analysis of Students Mathematical Concept Understanding Ability in Operation Research Course
Authors: Manda T G , Winanda R S , Rusyda N A 
Published: January 2021

AbstractThe purpose of this research to improve the students' mathematical concept understanding ability who receive the Scientific approach with PBL model learning compared to students who receive conventional learning in operation research courses through pretest. The sample was two classes of 2019 who took an operation research course. The data was analyzed by quantitative technique. The result of the research base on the pretest explained that it is known that the students' mathematical concept understanding ability is low.
The Used of E-learning Based on Android in Actuarial Courses
Authors: Suherman  , Fauzan A , Yerizon  
Published: January 2021

Abstract
This research is advance research that built an android application for the lecture process in e-learning for actuarial courses. This research aims to produce the learning designs to apply the applications developed in Actuarial courses. The product developed is a compilation of Semester Lecture Plans, Lecture Program Units, teaching materials, and queries. This research produced an android application program for e-learning in Actuarial lectures at the Mathematics Education Study Program Department of Mathematics, Faculty of Mathematics and Natural Sciences, UNP Padang.
The Development of Student Worksheet Based on Realistic Mathematics Education in Ordinary Differential Equations of Order-1
Authors: Yarman  , Fauzan A , Armiati  , Yerizon  , Lufri  
Published: January 2021

Abstract
Students' mathematical communication skills are still low and need to be improved. Learning tools do not support the student learning process. This study aims to produce a learning trajectory for lst-order differential equations. This type of research is a Plomp type research design consisting of three phases: (1) preliminary phase (preliminary research phase), (2) prototyping phase (prototype development phase), and (3) assessment phase (assessment phase). This section reports the preliminary phase. The conclusion is that the device has not facilitated students to make their own strategies to find concepts. Students need teaching materials in the form of worksheets that contain contextual problems that are close to students and facilitate student learning flow in rediscovering the theoretical concept of Ordinary Differential Equations (ODE).
On Locating Chromatic Number of H = Pm
∪ Wn
Authors: Anti A. , Welyyanti D. , Azhari M. 
Published: January 2021

Abstract
A married of vertex coloring partition and dimension of graph, became a definition of locating chromatic number of graph. That draught only can apply for connected graph. Because that, Welyyanti et al. expand concept of the locating chromatic number for disconnected graph. For this paper, the locating-chromatic number of disconnected graph contains one path and wheel graph as its components, is determined.
Development of constructivism-based mathematics interactive learning media tools on the material of constructing a flat side space for class VIII junior high school students
Authors: Rullis R M , Fauzan A 
Published: January 2021

Abstract
This study originated from students who had difficulty understanding the material of flat-sided shapes. Students often make mistakes in solving flat-sided shapes, including errors in calculations, and students having difficulty in visualizing images, especially in the material of flat-sided shapes. Also, many students still entered the formula incorrectly. One way to overcome this problem is to develop media-based interactive learning with a constructivist approach. This study aims to produce constructivism-based interactive mathematics learning media that is valid and practical on flat-sided building materials for class VIII junior high school students. This study describes the effectiveness of constructivist-based interactive learning media that is valid and practical flat-sided building materials for junior high school students VIII. The type of research used is development research using the Plomp model, which consists of three phases: the initial investigation phase, the development phase or prototyping, and the assessment phase. The preliminary research needs analysis, curriculum analysis, student analysis, and concept analysis were carried out. At the stage of developing or making a prototype, the researcher designs constructivism by paying attention to content, language, presentation, and graphics. Media-based interactive learning constructivism is validated by experts in mathematics, media, technology, and language education. Practicality is seen through the analysis of the implementation of learning observations, interviews, and student and teacher response questionnaires. Effectiveness is seen through the results of the analysis of student activities and learning outcomes.
The practicality of learning design based on realistic mathematics education for probability topic of grade VIII junior high school
Authors: Sya’bani F , Armiati  , Permana D , Arnawa I M , Asmar A 
Published: January 2021

AbstractThis study aimed to determine the practicality of Realistic Mathematics Education (RME) based learning design for probability topics. Probability is a learning topic that is close to daily life and is expected to assist students in developing students' communication skills. The Learning design development was done by combining two designs, namely the development design of Plomp and Gravemeijer & Cobb; meanwhile, to find out the practicality of the design, data collection was done in the form of filling out questionnaires by teachers and students. The data obtained were analyzed quantitatively and qualitatively. From the research conducted, it was obtained that the RME-based learning design for the topic of Probability was practical so that the RME-based learning design of probability topics that were implemented to teacher books and student books could be used to develop mathematical communication skills of grade viii junior high school students.
Study of factors affecting student learning outcomes in Real Analysis lectures during the Covid-19 pandemic
Authors: Helma H , Murni D 
Published: January 2021

Abstract
The competencies to be achieved in the Real Analysis course are 1) prove simple math statements with familiar concepts and 2) develop critical, creative, structured, and systematically thinking skills. This competence can be improved by using flow proof-based teaching materials and direct interaction in class between lecturers and students. During the Covid-19 pandemic, direct interaction in class was replaced with online learning. Of course, online interactions will affect student learning outcomes. What are the factors that affect student learning outcomes in real analysis lectures during the Covid-19 pandemic? By using a questionnaire, data about these factors were obtained. The factors affecting of learning outcomes during the Covid-19 pandemic are student background, learning attitude, and learning style. In particular, the indicators that influence student learning outcomes are the ease of obtaining internet access, the need for time to study that is not in accordance with the schedule, not confident in solving Real Analysis problems/exercises, not being able to understand Real Analysis material independently, and student learning styles.
Developing Learning Model Base On PMR Approach at Senior High School to Improve Student’s Motivation
Authors: Azizah N , Fauzan A , Lufri  , Arnawa I M 
Published: January 2021

Abstract
There are several factors that cause the low achievement of students' mathematics learning outcomes in several senior high schools in the Dharmasraya district, the main factor is many students have difficulties in solve mathematic problems in their daily life, that caused the low of students achievement of students, including daily assessment and national assessment. The purpose of this research is for developing learning model base on realistic mathematic education (RME) approach. Developing learning model on topic Implementation of sequences and series based on RME is an effort for helping students in solving mathematics problems that they find in their daily life. The subject of this research is students grade XI of SMAN 1 Koto Salak. The method of this research used is design research using the Plomp development model. The techniques of data collection implemented using observation, questionnaires and assessment of mathematical test. The techniques of data analysis used are descriptive quanlitative and quantitative. The results of this research showed that the learning design with topic Implementation of sequences and series based on PMR approach has; The average value of HLT validity is 4.11 with a very valid category. The practical test of learning books applying PMR-based sequences and series by teachers and students is 85.02 and is classified as very practical. The average value of students' motivation in learning after being tested 83.3 and it means PMR approach also can improve student’s motivation in mathematics learning.
The effect of mind mapping on the concept comprehension abilities for grade x automotive student of vocational public schools in Sijunjung regency
Authors: Sefriyanti D , Syarifuddin H , Arnawa I M , Asmar Ali 
Published: January 2021

Abstract
Concept comprehension abilities is a very important aspect in learning mathematics. The low of concept comprehension abilities will affect the quality of student learning, which in turn has an impact on the low achievement of students in school. This also happened at the Vocational public School in Sijunjung regency. One effort that can be done in reacting to it is through the selection of learning models that can create a learning environment that makes students active. Mind Mapping technique is an alternative to increase student activity in learning. This type of research was quasi-experimental. The instrument used in this study was a test consisting of an initial ability test to see students 'initial abilities consisting of high and low initial abilities, a final test to see students' mathematical concept comprehension abilities. Data was analyzed by using the Mann Whitney U test and two-way ANOVA. Based on the results of data analysis, several conclusions were obtained, namely: (1) The Concept comprehension abilities of students who learn with Mind Mapping Techniques was higher than students who learn with conventional learning; (2) Concept comprehension abilities of high, moderate, and low prior knowledge who learn with Mind Mapping techniques was higher than students who study with conventional learning; (3) there is no interaction between model of learning and prior knowledge.
The Effects of Problem Based Learning (PBL) Model on the Improvement of Student’s Mathematical Problem-Solving Skill in MAN in Pekanbaru City
Authors: Jannah N , Yerizon  , Arnawa I M 
Published: January 2021

AbstractBased on the preliminary study indicate that the problem-solving abilities of students of MAN Pekanbaru City are still low. The purpose of this research is to investigate the effect of PBL model on the improvement of student’s problem-solving skills in the 11thclass MAN Pekanbaru city. The data in this research was collected by using problem-solving test, and analyzed by using paired t-test. The results showed that the problem-solving skills of students after implementing PBL model is better than before. This result means PBL model takes effect on the improvement of student’s problem-solving skills.
Discussion on the Application of Layering Technology in the Development of Computer Software
Authors: Wang Aihua 
Published: January 2021

Abstract
Computer software is an important way for computers to achieve various functions. With the popularization and application of computer technology, people also put forward new requirements for computer software development technology. Traditional single-level software development technology can no longer meet the actual needs of computer technology applications at this stage, so we must actively apply layered development technology. Computer software developers should strengthen their understanding and research on layering technology, and make full use of layering technology to improve the function, quality and speed of computer software. This will help newly developed computer software to better adapt to the requirements of the network information society in the new era, thereby promoting the modernization of China’s social economy.
RETRACTED: Access Point Authentication Scheme of SCADA System Based on Cloud Computing Technology
Authors: Shen Jiayuan , Xu Jun , Cai Kun , Ji Yan 
Published: January 2021

Abstract
Aiming at the security problem of the SCADA system introduced into cloud computing that lacks a credible identity authentication mechanism, this paper proposes a cloud computing-based SCADA system access point authentication scheme. In this scheme, a cloud service security access protocol for SCADA system is proposed. The protocol uses password based identity authentication technology to screen the identity of the terminal node, and effectively identifies the illegal access point by authenticating the access point. By this method, the user’s private information is prevented from being intercepted and tampered maliciously.
A Detection System for Rail Defects Based on Machine Vision
Authors: Zhou Qianxi 
Published: January 2021

Abstract
In this work, a machine vision based detection system is designed and applied to identify the region of rail track need to be polished. The CCD industrial camera is employed to obtain the RGB color space images on the railway line in real time. To reduce the effect of environmental brightness, the obtained RGB space images are transformed into HSI color space. Then, the noise was removed from the grayscale image by the Gaussian blur to remove the interference elimination of the acquisition signal. According to the calculated saturation and hue values, the threshold of saturation and hue values is set for the following image segmentation, respectively. At last, the accurate position information of the rail track region needs to be polished is obtained for the subsequent grinding processing. By employing the machine vision system, high-efficient automatic rail defects grinding could be realized.
Research on LRU Hierarchy based on Optimal Granularity Level
Authors: Fei Yang , Dong Shuo , Shi Li-Zhong 
Published: January 2021

Abstract
In order to improve the convenience of replacing faulty equipment on the route and realize LRU(Line Replaceable Unit) level planning reasonably and effectively, a LRU hierarchical division method based on optimal granularity level is proposed. Based on the analysis of the relationship between the components in the product structure, the design structure matrix theory is introduced to construct the comprehensive relationship matrix, which quantifies the relationship between the components from two levels of function and structure. By defining modularization index, combining with the hierarchical traversal of product structure tree, the optimal granularity level is calculated. This method can provide a division scheme based on hierarchical factors for LRU planning and provide support for getting more optimized LRU planning and design.
Research on the Selection of Maintenance Equipment Purchasing Mode in Equipment Distribution Process
Authors: Yue Shuai , Shi Xianming , Wang Yabin , Rong Liqing , Tian Wenjie 
Published: January 2021

Abstract
Maintenance equipment is an important material basis of equipment distribution, and the procurement of maintenance equipment is a key link in the implementation of equipment distribution, which plays a very important role in ensuring the integrity rate of equipment. Compared with the traditional purchase of weapons and equipment, the purchase of equipment maintenance equipment has its own unique situation. In the process of choosing purchasing methods, there is a lack of specific theoretical guidance. Aiming at the practical problems of maintenance equipment procurement in current equipment distribution, this paper focuses on the characteristics of equipment maintenance equipment procurement, combs the applicability, advantages and disadvantages of various procurement methods, and puts forward some suggestions for reference.
Optimal Parameter Study of the External Inverting Die
Authors: Wen Hailong , Zheng Yuqing , Fei Yiting 
Published: January 2021

Abstract
In the external inverting process of thin-walled circular tube, buckling instability often occurs in the straight line section of thin-walled tube due to the size mismatching of forming die. Based on LS-DYNA971, the finite element modeling was built up and a series of simulation calculations were conducted about the external inverting process of thin-walled circular tubes on two circular arc dies under axial compression. The inverting plastic deformation of a Q235 steel thin-walled tube with an outer diameter of 60mm and a wall thickness of 2mm was reproduced on two die types with different fillet radii. The simulation results show that the optimal induced fillet radii of the dies is 10.7±0.1m, and meanwhile the thin-walled tube head has good formability in the early stage, which is convenient for the subsequent shape operation of the invertube. This paper provides a method reference for the die structure design used for inverting the thin-walled tube.