bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel HTS coil protection method using secondary windings as a quench heater
Authors: Onodera Y , Mito T , Takahata K , Hirano N 
Published: June 2020

Abstract
In NIFS, research and development of HTS magnets have been begun aiming at the application to a next experimental device of Large Helical Device which is a heliotron-type fusion plasma experimental device. The next experimental device needs large coil current density such as 80 A/mm2, therefore it is important to develop a coil protection method. In this study, we have proposed a novel coil protection technology of HTS magnets using secondary windings. By embedding secondary windings which are electrically isolated in a part of the conductor and using the secondary windings as a quench heater, the occurrence of normal conduction is quickly diffused, then prevented local temperature rise in the HTS coil. We applied this method to the conductor and coil under development, and analysed the thermal behaviour of the secondary windings. As a result, we found that the temperature rise of the entire coil can be suppressed and the hotspot region can be diffused. This shows the applicability of coil protection by using the secondary windings, therefore optimal coil protection is possible by changing the ratio of magnetic stored energy between internal consumption and external recovery depending on the value of external resistance.
Screening Current-Induced Field and Field Drift Study in HTS coils using T-A homogenous model
Authors: Berrospe-Juarez Edgar , Trillaud Frederic , Zermeño Víctor M R , Grilli Francesco 
Published: June 2020

Abstract
The emergence of second generation (2G) high-temperature superconductor (HTS) tapes has favored the development of HTS magnets for their applications in areas such as NMR, MRI and high field magnets. The screening current-induced field and the field drift are two major problems hindering the use of HTS tapes in the mentioned areas. Both problems are caused by the screening current, then it is necessary to have a modeling strategy capable to estimate such phenomena. Thus far, the H formulation has been a widely used approach to model medium-size systems (hundreds of tapes). However, its application to large-scale systems is still impaired by excessive computation times and memory requirements. Homogenization and multi-scaling strategies have been successfully implemented to increase the computational efficiency. In this contribution, we show that using the homogenization technique with the recently developed T-A formulation allows reducing the computation time and the amount of memory up to the point that realtime simulations of slow ramping cycles of large-scale systems are possible. At the same time, the T-A homogeneous model provides enough resolution to investigate the screening current using numerical simulations.
Measurement of splice resistance and normal zone propagation velocity in REBCO tapes for the Superconducting Link of HL-LHC
Authors: Matras M. , Fleiter J. , Ballarino A. 
Published: June 2020

Abstract
The Superconducting Link (SC-Link) being developed at CERN in the context of the LHC High-Luminosity upgrade (HL-LHC) will supply the current to superconducting magnets of the HL-LHC Inner Triplets and Matching Sections. The SC-Link consists of MgB2 highcurrent cables, and it includes high temperature superconducting REBCO cables making the electrical transition between the MgB2 and the current leads. Electrical protection of superconducting devices made of REBCO against unexpected quenches is challenging especially when operation is at high current density. Adequate electrical protection of REBCO cables is crucial to insure good performance of the circuit over the lifetime of the machine; protection relies on the detailed knowledge of the quench propagation velocity. In this paper we reviewed the electromagnetic properties of REBCO tapes procured for prototype work. We measured the splice resistance (Rs
) of the REBCO conductors and found a significant variation among the different batches of conductor. The normal zone propagation velocity (NZPV) was reported to be affected by the interfacial resistance which is governing the splice resistance: increasing the interfacial resistance enhances the NZPV. In order to determinate the influence of the internal resistance on the quench behaviour of the tapes, we investigated the normal zone propagation velocity of the epoxy-impregnated tapes at 77 K in self-field and 4.2 K in field up to 7 T in the FRESCA test station. We found that despite the Rs
variation observed (up to factor 4), the tapes show similar NZPV at both temperatures. In addition we observed a significant field dependence of the NZPV of the tapes at 4.2 K. The results are compared to numerical simulation and discussed.
Electromagnetic Performance of 10-MW HTS Double-Stator Flux Modulation Generators Considering Distributed/Concentrated Armature Winding
Authors: Cheng Yi , Qu Ronghai , Gao Yuting , Zhang Yuanzhi , Wang Qian 
Published: June 2020

Abstract
For HTS conventional synchronous generator, the superconducting (SC) field windings or armature windings are rotating, which could complicate their industrial feasibility for the off-shore wind generation. In order to overcome this drawback, a kind of HTS double-stator flux modulation generator (HTS-DSFMG) with stationary seal is proposed. Meanwhile, the electromagnetic performances of 10-MW HTS double-stator flux modulation generators with two different armature winding structure, i.e., distributed and concentrated armature windings are compared in this paper. In detail, the magnetomotive force (MMF) harmonic and the saturation effect of each armature winding structure have been studied. The objective is to intensive study the advantages and disadvantages of HTS-DSFMG with different armature windings, and to find the suitable configuration of the armature winding for large scale HTS double-stator flux modulation generators.
Superconducting Propulsion System with LH2 Cooling for All-Electric Aircraft
Authors: Dezhin D , Dezhina I , Ilyasov R 
Published: June 2020

Abstract
The article discusses the advantages of using liquid hydrogen to cool superconducting electric machines for an all-electric aircraft. Calculation schemes and basic parameters of superconducting electric machines with liquid hydrogen cooling are presented. It is shown that liquid hydrogen is practically a non-alternative type of fuel for future electric aircraft because of its high energy intensity and environmental cleanliness.
Principal analysis of hybrid power systems with HTS electrical machines
Authors: Kovalev K L , Ivanov N S , Ilyasov R I , Penkin V T , Zechikhin B S 
Published: June 2020

Abstract
The hybrid power systems (HPS) for transport application are currently under consideration. It causes with ecological and fuel efficiency aspects. The successful solving the problems of enhancing the specific output power parameter, fuel efficiency and diminishing weight of such systems focus on a use the cryogenic cooling and cryogenic fuel as a source of on-board energy. The article is devoted to the analysis and comparison of HPS of different design. The comparison is provided for HPS with different fuel (diesel oil, kerosene, petroleum, liquid natural gas, and liquid hydrogen). The analysis of application in HPS of different types of conventional and HTS electrical machines illustrates the advantage of the latter. The prospective of application of cryogenic power electronics is considered like advanced for HPS. Besides the article provides specific parameters of the HPS with HTS generator, motor, cryogenic electronics and HTS power cable at different cooling
Temperature and strain rate effect on flow stress of al2075/bottom ash composite
Authors: Supriyanto F D , Seputro H , Rinaldi H , Akbar H I 
Published: June 2020

Abstract
This study focused to determine the flow stress of Al 2075 composites with bottom ash reinforcement. Metal forming process is very important in an industry, materials can be plastic deformed requires several parameters of the forming process, such as the material flow stress. Temperature and strain rate affect the flow stress material. In this paper the tensile test carried out at 350°C, 400°C and 450°C and the strain rate varied 1 mm.s−1, 10−1 mm.s−1 and 10−2 mm.s−1. Tensile test showed that the highest flow stress is obtained at 350°C and a draw rate of 1 mm.s−1, the higher the temperature will decrease the flow stress, while the faster the strain rate increased the material flow stress.
The failure farmers in panti district to control tungro disease which endemic in 2014-2019
Authors: Wahyuni W S , Sayekti J B A 
Published: June 2020

Abstract
Tungro disease in rice plants is transmitted by green leafhoppers (Nephotettix virescens) in a semi-persistent manner. This disease has spread in Panti District from 2014-2019, especially at the beginning and the end of rainy season. This paper wanted to explain why farmers in Panti failed to overcome the endemic tungro disease. The study was conducted by questionnaire and direct observation in the field. Actually farmers in this district had received integrated pest control (IPM) information, but they have not implemented properly. In 2018-2019, based on respondents at Kemuning Lor, Glagahwero and Pakis, most farmers planted rice along the year because of a good irrigation system. Although the plant was infected, the rice yield was still ± 40-60%, except for some field in Pakis (≤ 30%). The farmers in Pakis let their plants infected without hope, but they still grew rice continuously. A few farmers in Kemuning Lor controlled the vector mechanically by yellow light trap, other farmers used pesticides. The failure farmers to control tungro disease caused by several factors, i.e (1) continuous rice planting throughout the year, (2) the varieties grown were mostly remained, it was IR 64 which has good taste, and the selling price was more expensive than other varieties, (3) improper pesticide selection. Although they grew rice almost in the same time, but because of they planted continuously a year, the tungro disease still present there. Therefore, to reduce this damage, further education is needed on IPM and farmers' awareness is needed to work together to implement IPM properly.
Student’s perspective about electrical voltage of fruit cells through STEM
Authors: Setiawan A M , Munzil  , Marsuki M F , Nugraheni D , Hanifiyah F , Husnayaini N 
Published: June 2020

Abstract
The use of batteries in electronic tools can cause environmental pollution. This problem can be solved by using natural ingredients that can replace conventional batteries as a source of electrical voltage. This topic is suitable for students to learn in class by reviewing aspects in the fields of Science, Technology, Engineering, and Mathematics (STEM). For STEM’s activities, we used Yuenyong’s Science-Technology-Society (STS) approach, and for data analysis, we used mixed methods, where quantitative methods to classify the data and qualitative methods to analyze student perspective. In this study, students are given lemons, limes, potatoes, apples, tomatoes, and cucumbers as fruit cells. Then all fruits are connected by coins, nails, cables, multimeters, and LED lamps. The results obtained by students is conventional batteries cells can be replaced by fruit cells. All fruit cells that we used like cucumber, apples, tomatoes, limes, lemons, and potatoes are capable of producing electrical voltage. Cucumbers and tomatoes produce the higher electrical voltage (5,0 volts & 3.0 volts) but have a dim LED’s light, while potatoes, lemons, limes, and apples produce the lower electrical voltage (1.35 volts, 2.0 volts, 2.2 volts, and 3.4 volts) but have bright LED lights.
Development of learning media using VBA excel in physical learning in senior high school
Authors: Safitri A D , Lesmono A D , Maryani  , Wardoyo A A 
Published: June 2020

Abstract
This study aims to examine the practicality and effectiveness of instructional media. This research uses research and development research. The development procedure in this study uses 4D which has four stages namely define, design, develop, and disseminate. This study examines the disseminate stage of validating testing. The results of the development stage to state that they are valid, practical and effective. The subject of the dissemination stage of this study were students of class XI MIA-1, XI MIA-2, and XI MIA-4 at SMA Umbulsari. Data collection is done through pre-test and post-test and student questionnaire responses. The results of validating testing at the disseminate stage to measure the practicality of learning media carried out by XI MIA-1, XI MIA-2, and XI MIA-4 respectively scored 81.32%, 80.20%, and 81.46%, obtaining criteria practical and get effective enough criteria for the effectiveness of learning media using VBA Excel with a score of 40.05% at XI MIA 1, 36.21% at XI MIA 2 and 39.23% at XI MIA 4 based on the N-Gain test criteria.
The analysis of the application of learning materials based on project-based learning to improve the elementary school students’ creative thinking skills in solving contextual division problems
Authors: Shalihah N H , Dafik  , Prastiti T D 
Published: June 2020

Abstract
This study aims to investigate the analysis learning materials implementation based on project-based learning to improve the elementary school students’ creative thinking skills in solving contextual division problems. This type of research is using a mixed research, which is a combination of quantitative and qualitative methods. The research respondents consist of two classes, namely a control class as many as 19 students and an experimental class as many as 20 students. The results shows after the implementation using the application learning materials base on project-based learning, it was found that the presentation of students' creative thinking skills for the control class are 77,19% for fluency, 70,18% for flexibility, and 56,14% for novelty. While the experimental class are 82,5% for fluency, 91,67% for flexibility, and 67,5% for novelty. Then the score of the indepent sample t-test from post-test shows that there is a significant difference between the control class and the experimental class with the sig (2-tailed) value is 0.000 (p = <0,05). It can be concluded that the application learning materials base on project-based learning can improve students' creative thinking skills in solving contextual division problems.
The matthayom and senior high school student’s metacognition profile on solving pisa test shape and space content based on van hiele level
Authors: Firmansyah F F , Aribowo B E , Damayanti R , Sari M P , Sunardi  , Yudianto E 
Published: June 2020

Abstract
Profile of the students’ metacognition observed in this research was an activity that involved the abilities and metacognition processes of the students at each level of van Hiele thinking, including knowledge of metacognition and metacognition settings in solving geometrical problems in shape and space content. This type of research was descriptive with qualitative approach. Descriptive research was used in this research because it described or explained the variables studied, namely the level of van Hiele and Metacognition in schools in Indonesia and Thailand. The data collection methods used were van Hiele, PISA and interview tests. The results of the data analysis found that the students of visual level in Indonesia and Thailand in the planning stage were able to think about what to do, but in the monitoring stage, the students asked themselves questions about the purpose of the problems. However, in the evaluation stage they still doubt of what they decided, the students of analysis level in Indonesia and Thailand in the planning, monitoring and evaluation stages were quite sure of what they have thought.
The analysis of the implementation of multi techniques based learning media in improving the elementary school students’ higher order thinking skill in solving exponential problem
Authors: Masruroh L , Dafik  , Suprapti  
Published: June 2020

Abstract
This study aims to investigate the analysis of the implementation of multi techniques based learning media in improving the elementary school students’ higher order thinking skill in solving exponential problem. This is caused by the lesson plans cannot motivate students to improve higher order thinking skills. The method used in this study is a mixed method which is a combination of quantitative and qualitative methods. The research subjects were the fifth grade students of elementary school consisting of 25 students of experimental class and 24 students of the control class. The instruments of this research are an interview, a questionnaire, observation, and documentation. Quantitative method is applied to analyze the difference of student achievement result among two classes, while the qualitative method is applied to analyze the students' higher order thinking skills. The results show that there are significant differences between the two classes that applied multi techniques based learning and conventional learning. The statistical result indicates that the (2-tailed) significance of the independent sample t-test in the pre-test was 0.000 or α ≤ 0.05. It implies that the implementation of multi techniques media affects the students' higher order thinking skill in solving exponential problem.
Optimization of Management System of Independent Enrollment Based on Quantum Evolutionary Algorithm
Authors: Wang Yanqin 
Published: June 2020

Abstract
The independent enrollment of colleges and universities is a heavy task for colleges and universities. With the development of information technology, when colleges and universities conduct independent enrollment, many data hit in a flash. The statistical analysis of data brings difficulties to the general independent enrollment management system. This paper relies on quantum evolution algorithm to optimize the independent enrollment system, aiming to sort out and optimize the enrollment, the work flow of student management provides real-time data query and analysis services for relevant functional departments and individuals, realizes the linkage between the enrollment system and other systems of the school, improves the efficiency and management level of enrollment management, effectively improves the efficiency of independent enrollment, opens data interface for the access of other systems, and provides new work, student information management and financial management in the later stage work provides convenient and efficient information support.
Multi-attribute Probability Caching Algorithm in Named Data Network
Authors: Zhang Li , Zhang Qiang 
Published: June 2020

Abstract
Since entering the new century, Internet technology has developed rapidly and has become an important infrastructure in today’s society. In recent years, with the popularization of optical fiber applications, the network bandwidth has been greatly improved, and the growth rate of network traffic has also shown explosive growth. The traditional TCP/IP network has exposed many serious problems in the face of increasing traffic. In particular, the issues of scalability, reliability, security, flexibility and mobility are more prominent. In order to solve the shortcomings of the existing Internet architecture, the current domestic and international schemes mainly include "improvement" and "revolution". Improvement is the gradual improvement of the deficiencies of the existing Internet system. However, this method cannot essentially solve these deficiencies, and it is difficult to meet the needs of future network development. The revolution is to redesign the information-centric network as the Internet system structure, completely changing the existing Internet system in terms of scalability, security and mobility, in order to adapt to the needs of future social development. Named-Data Networking (NDN) in many information-centric network architectures is a network architecture with excellent research and development. This article focuses on the research of NDN network caching technology. In terms of caching decisions, a multi-attribute probabilistic caching algorithm is proposed, which can effectively reduce the cache of redundant data in routing nodes in NDN networks and improve the utilization of routing node cache space, reduce network delay, increase the cache hit rate of routing nodes, and improve the overall performance of the NDN network.
Research on control algorithm of the upper limb rehabilitation robot based on PI hysteresis compensation
Authors: Zhiming Wang , Wangwei Ye , Sijia Gong , Qi Hua 
Published: June 2020

Abstract
The upper limb rehabilitation robot is used to assist patients with upper limb hemiplegia for rehabilitation training. During the passive rehabilitation training of the patient, the trajectory of the rehabilitation training must be as smooth as possible, so that the patient will not feel discomfort when pulling the affected limb. The passive control algorithm of the existing upper limb rehabilitation robot is not ideal for the lag processing of the system. This paper designs a passive control algorithm based on PI hysteresis compensation. The hysteresis effect of the system can be greatly reduced by introducing the hysteresis compensation term uc
. Experimental results show that the algorithm can effectively eliminate the hysteresis effect of the system.
An improved salp optimization algorithm inspired by quantum computing
Authors: Tian Fanghao , Wei Hongkui , Li Xu , Lv Meibo , Wang Pei 
Published: June 2020

Abstract
Salp Swarm Algorithm (SSA) is a novel optimization algorithm which is widely used in engineering problems. An improved SSA inspired by quantum computing is proposed in this paper. The principles of quantum computing, such as qubits and quantum states, are introduced into the original SSA in order to overcome the defect of trapping into local optimum easily. Instead of updating the salp position directly, the quantum angle related to the quantum state is updated to increase the diversity of states. Two multidimensional benchmark functions are used to verify the proposed improved SSA, the result shows that the introduction of quantum computing can successfully prevent the SSA from falling into the local optimum and increase the accuracy.
Research on weak fault signal detection technology based on lv system
Authors: Wang Weihao , Liu Shuyong , Chai Kai , Chen Long 
Published: June 2020

Abstract
The detection of weak fault signals is realized by applying non-resonant parametric excitation to Lu chaotic system. Periodic signals far larger than the characteristic frequency of the system are taken as input, the sharp change of the system attractor is observed, and the existence of weak signals is detected. The conditions that the parameters of the detection system should meet are deduced by using the averaging method and Lyapunov method. Numerical research shows that the detection system can quickly reach a stable state. When the amplitude of the detected weak signals changes slightly, the attractor state changes abruptly, and the system is sensitive to the input. Through the "butterfly effect" of the system, feature signals that are difficult to extract by traditional methods can be detected. And the system has strong anti-interference performance.