bluuebunny/crossref_metadata_2025 huggingface dataset:
Web-based student master book information system in vocational school of Muhammadiyah Banyuresmi
Authors: Maulani G A F , Suryadi A , Nugraha Y , Hamdani N A , Purwanti Y
Published: November 2019

The main student book information system is a web-based application that comes as a form of modernization from a manual student main book that can streamline, and streamline the time in importing, searching, etc. This application is made as simple as possible so that it is easy to use by the user, in terms of interfaces and interactions in the application so even for novice users it will be easy to understand, but even though simple, this application can contribute a lot of reasons, the Student Parent Book is the most important book in school administration. Especially data management of students, the Student Parent Book Information System Application is based on localhost (local network), meaning that when you want to access it does not need to be connected to the internet, just connect to the local network and can only be accessed by users who are connected with the admin, or recorded by admin as someone who has access rights.
The effectiveness of using integrated science practice worksheet of integrated type to enhance environmental literacy
Authors: Nurhayati  , Hernani  , Sinaga P
Published: November 2019

The aim of this study is to know the effectiveness of the use of integrated science practice worksheet of integrated type to enhance environmental literacy. The method used in this research was quasi experimental method. The research design uses non-equivalent pretest-posttest control group design. Students from two classes in one school took part in this research. The environmental literacy instruments are arranged by adopting and modifying problems from the MSELS (Middle School Environment Literacy Survey). Data was collected from 64 students divided into experiment class and control class. Data analysis uses statistical data analysis and impact effect (effect size). The results showed that there was a significant difference from the enhancement of environmental literacy of the control class and experimental class after treatment was given, whereas based on the size of the impact it has the value of the big categorical effect size. Therefore, integrated science worksheet of integrated type is effective to enhance students’ literacy ability.
Using argument-driven inquiry to promote students’ concept mastery in learning global warming
Authors: Salsabila E R , Wijaya A F C , Winarno N , Hanif S
Published: November 2019

The process of learning science in some schools is still in the form of direct transfer from teacher to student. The learning process will be meaningful if the students involved and explore more in building a concept. The aim of this study is to investigate the impact of Argument-Driven Inquiry on students’ concept in learning global warming. The method that is used in this research was quasi-experiment. The study used two classes with one experimental group that used Argument-Driven Inquiry and one control group that used Inquiry-based Learning. The population of this study is seventh-grade students in one of Secondary School in Bandung, Indonesia. The sample is chosen by purposive sampling technique. The participants consist of 52 students from the experimental group and the control group. Each group consists of 26 students. The result of this study shows the improvement of students’ concept mastery in the experimental group is obtained as 0.45 and for the control group is 0.28. Based on the result, Argument-Driven Inquiry gives the better impact in improving students’ concept mastery. Argument-Driven Inquiry can be considered as one of the teaching models that can be implemented in Junior Secondary School.
Factors influencing pre-service science teacher’s GPA on bilingual science teacher education program
Authors: Nugraha I
Published: November 2019

The needs for English speaking teachers in major cities continue to rise along with the increasing number of multicultural students due to population growth. The challenge to fulfil the need has an implication with how the teachers for the future are selected and prepared. This study seeks to explore the possible effects of gender, origin, school type, entry qualifications (Test of English as a Foreign Language/TOEFL) score on student performance (Grade Point Average/GPA) in a bilingual science teacher education program in Indonesia. This study was a cross sectional survey study in first year students who enrolled science teacher education program. The study employed of a sample of (N=62) of a first-year student enrolling science teacher education program. The results from Path Analysis via regression to predict factors influencing student’s GPA scores posited that there is no direct effect of student’s origin on GPA and TOEFL has a direct effect on GPA. From this study, the recommendation is to conduct a follow up program on bilingual science teacher program to improve students TOEFL scores because TOEFL score has a direct effect on student’s GPA.
Smart edu design as a 21st century learning system innovation in optimizing one of the roles of universities
Authors: Zulkarnaen R H , Setiawan W , Rusdiana D , Muslim M
Published: November 2019

The development of science and technology is closely related to the quality of higher education. Science and technology innovation is used as a tool to empower communities so that they can develop sustainable development. The survey results at one of Indonesia’s private universities showed the low role of universities in schools as their environment. The progress of science in universities is very fast but different from the situation in the environment. This indicates an imbalance in the development of knowledge that occurs in universities with schools. Based on the results of a literature study, the smart edu design is used as an alternative solution in this regard. Smart edu is a managerial learning system innovation adapted from the smart city concept. Features in this program allow students, lecturers and teachers in the field to interact with each other. Students can assess the problem without having to go to the field on the other hand the teacher can assess the solution which is the result of learning between the student and the lecturer. Thus the learning transparency can be built through this system so that the inequality of knowledge development can be overcome.
The literacy of physics concepts on petroleum exploration: A case in West Java
Authors: Rochman C , Novia A , Nasrudin D , Malik A , Dirgantara Y , Rokayah  , Hermita N , Muslim
Published: November 2019

Since the beginning of the 19th century, petroleum began to be explored in Indonesia which was pioneered by the Dutch which can be further explored by the Indonesian nation. This shows that at that time the nation of Indonesia has started literate. But now most of the Indonesian people are allegedly lacking to understand how the process of petroleum exploration. Based on these assumptions this study aims to obtain exploration literacy data in the area of Bekasi based on physics concepts in learners. Participants of this study are learners from high school are close and far from the location of petroleum exploration. The research method used will be pragmatic explorative. Data collection tools are literation questions consisting of processes, concepts, contexts, and attitudes toward petroleum exploration and interview guidelines. The results showed that the average literacy of the physics concept of students in the low category. This study recommends the need for enrichment materials on petroleum exploration based on local wisdom
The Improvement of mathematical generalization reasoning of university students by concept attainment model
Authors: Angraini L M , Kusumah Y S , Dahlan J A
Published: November 2019

This study aims to look for the improvement students of university on mathematical generalization reasoning by concept attainment looked from overall, Prior Mathematical Knowledge (PMK) and interaction between learning models and PMK toward mathematical generalization reasoning. This research is designed by Quasi experiments. The one of State Islamic Universities is the place of this research. This research used Kolmogorov-Smirnov test, Levene test, t-test, two-way for analysing the data. The results of this study are: (1) The students’ improvement on mathematical generalization reasoning who taught by concept attainment model is better than those who taught by conventional learning looked from overall; (2) There is interaction between learning models and PMK toward students’ improvement on mathematical generalization reasoning.
Mathematical connection ability of deaf student in completing social arithmetic tests
Authors: Leton S I , Wahyudin  , Darhim
Published: November 2019

This study aimed at exploring the mathematical connection ability of grade 8 deaf students in completing the social arithmetic test. This was a qualitative research with case study and grounded theory design. The data were collected by test, interview, observation, and questionnaire. Subjects of the study were six students who were purposively chosen based on the characteristic of language and speech, intelligence, and social emotion and were taken from three different schools, namely: SMPLB Karya Murni Ruteng - NTT, SMPLBN Semarang and SMPLB Don Bosco Wonosobo. The result of work and interview analysis showed that mathematical connection abilities of deaf students in completing social arithmetic test are as follows; (1) in understanding the problem, the deaf students tended to represent the problem by creating a mathematical model, statement, and concrete objects. (2) in making the initial plan to complete the problem, the deaf students tended to use media associated with a given problem. (3) If deaf students could solve the problem, they tended to resolve it by enumerating, substitution, and tinkering with concrete objects.
Learning arithmetic with back sound music classic romantic
Authors: Karlimah
Published: November 2019

This study is based on our previous research results, that classical music can improve the mathematical intelligence of elementary school students. But the learning model used has not been studied, therefore done further research to develop the model of learning mathematics with back sound classical music of the era romantic. The research method used is Design-Based Research (DBR). Development using four stages, adoption and modification of Reeves development design. Research subjects were the same teachers and students in the previous study. The study was conducted for eight months. The product of learning model is named Romantic Learning Arithmetic Model. The result of the research shows that the Romantic Learning Arithmetic Model is started from the beginning activity which is opening and conditioning learning, giving motivation to learn, doing apperception and learning orientation; the core activities of presenting learning, giving learning direction, independent learning experience, and presentation of learning outcomes, and the final activities of evaluation, follow up, and closing.
Mathematically gifted student’s ways of thinking on fractions
Authors: Ikhwanudin T , Wahyudin  , Prabawanto S
Published: November 2019

This research aims to analyse mathematically gifted student’s ways of thinking on fractions learning. The respondent was one mathematically gifted student of the 7thgraders in the junior high school. The research approach was qualitative. The data were collected through paper and pencil measure, observation, and interview. The data were analyzed by grounded theory with coding and constant comparison. The results showed five mathematical thinking types; those are quantification, schematization, symbolization, concretization and analogical thinking. The findings are then elaborated using some related theories to justify the results.
The analyzing of students’ learning obstacles in understanding proportion
Authors: Wijaya A P , Yunarti T , Coesamin M
Published: November 2019

In order to achieve learning objectives optimally, learning is designed with attention to students’ learning obstacles. The purpose of this research was to analyze the obstacles of junior high school students in understanding proportion. The subject of this research was 87 students of grade 7 at one of junior high school in Bandar Lampung, Lampung, Indonesia. This study used a qualitative method. The data of this research were obtained through test and interview. Based on the results of the research, 75.86% of students have obstacles in understanding proportion. The obstacles include ontogenic obstacle, epistemological obstacle, and didactical obstacle. The dominant obstacle that was appear was the didactical obstacle.
Designing an algebra learning sequence: the case of operations on algebraic expressions
Authors: Jupri A , Usdiyana D , Sispiyati R
Published: November 2019

This study aims to design a learning sequence for algebra learning on the topic of operations on algebraic expressions—which is taught for junior high school students. To do so, we used design research method, particularly the preliminary design phase. First, we compiled student difficulties in the topic of algebraic expressions from previous relevant studies. This compilation is used as a consideration for designing a learning sequence. Second, we designed the learning sequence based on the theory of realistic mathematics education. This theory is used because it offers meaningful mathematics for students. Finally, we conducted a focus group discussion to revise the design in order to produce a ready-use learning sequence for the teaching experiment. The result of this study included a sequence of algebra learning material on the topic of operations on algebraic expressions. In sum, we consider that the designed learning sequence for this algebra topic is more meaningful than the conventional learning sequence for students.
Relationship among pre-service teacher conception of geometry and teaching skills
Authors: Dewi I L K , Asnawati S
Published: November 2019

The purpose of this research is to find out the correlation between understanding the geometry concept of mathematics pre-service teacher and teaching ability, in explaining the concept of geometry systematically in a planned order, so that the students are easier to understand. Geometry concepts include (1) visual skills, (2) descriptive skills, (3) drawing skills, (4) logical skills, and (5) applied skills. The research method is an experiment, and the sampling technique is purposive. The research instrument is a practice test. Data understanding of geometry concept comes from the Final Test of Geometry course, while the data of teaching ability comes from teaching practice score on geometry topic. The statistical test uses the Pearson Product Moment correlation test and linearity test. The results of this research are: (1) there is a significant correlation between students’ concept comprehension ability and geometry teaching ability; (2) the relationship between students’ conceptual understanding and geometry teaching ability is in the medium category; (3) the magnitude of the influence between the understanding of student concepts and geometry teaching ability is 46.5%. It indicates that there is another factor of 53.5% that affects the ability of pre-service teacher teaching on geometry topics in addition to student concept comprehension.
Overcoming students’ misconceptions about simple harmonic oscillation through interactive conceptual instruction (ICI) with computer simulation
Authors: Maulidina W N , Samsudin A , Kaniawati I
Published: November 2019

Physics is a part of science that contains many concepts. To understand a physics concept student often experience misconceptions, including on simple harmonic oscillation subject. One way to overcome students’ misconceptions is to conduct teaching instruction that can facilitate students to promote their conceptual understanding. Interactive Conceptual Instruction (ICI) was developed to promote conceptual understanding. The data were obtained through 60 10th grade student that selected by simple random sampling. They were divided into two group which is 30 students in the experimental group taught ICI with computer simulation and 30 students in the control group followed traditional classroom instruction. The instruments utilized to determine students’ misconceptions were pre-test and post-test in the form 20 items four-tier diagnostic test related to simple harmonic oscillation. The results show that the value of effect size is in the “large effect” category. It can be concluded that the implementation of ICI with computer simulation effective in overcoming student’s misconception on simple harmonic oscillation subject.
Stakeholder view of competency profiles (pedagogical, professional, social and personality) graduate of the physics education
Authors: Dirgantara Y , Malik A , Samsudin A , Yuningsih E K , Chusni M M , Agustina R D , Fairuzillah M N
Published: November 2019

Departing from the increasingly fierce world of work, every study program at various universities needs to prepare graduates that are able to compete for the global world. This study aims to determine the level of competence of undergraduate graduates of physics education program UIN Sunan Gunung Djati Bandung, especially pedagogic, professional, social and personality competencies as well as efforts to improve the weakness of prospective teachers in welcoming the world of work. The method used is survey. The subjects of this study are graduates of physics education program. The instrument used is a questionnaire filled by the supervisor of graduate users. Analysis of data obtained based on a percentage of answers to respondents, then qualified as the good category, good, enough and less. The result of the research shows that physics education physics graduate of UIN Sunan Gunung Djati Bandung pedagogic competence has a good qualification (69%), professional competence has a good qualification (68%), social competence has a good qualification (67%) and well-qualified personality competence (71%). Thus, in general, the competence of physics education program graduates UIN Sunan Gunung Djati Bandung is good and acceptable by stakeholders.
An analysis of students’ mental models using temperature and heat transfer-diagnostic test (THT-DT)
Authors: Dewi R , Samsudin A , Nugraha M G , Liliawati W
Published: November 2019

Students’ mental models can be identified through a students’ concept understanding. In one study found that one of the students’ difficulties in learning physics is to understand the concepts of physics, so it can be identified that students have a low mental model. The purpose of this study was to analyse students’ mental models based on the level of understanding by using diagnostic tests. The instrument has been developed in the form of four tier test to analyse mental models in temperature and heat concept. The results obtained from the test, classified according to the category of mental models of students. This research method was used as the 4D model (Defining, Designing, Developing and Disseminating). The subject of the study was 26 eleventh grade students (average age 16 years) and has been studying the material temperature and heat transfer. Research results show that 7.37% students in scientific model level, 68.31% students in synthesis level, and 23.72% students in initial model level. In conclusion, the development of THT-DT four-tier test-items is one of potential diagnostic test instrument that able to analyse the level of student’s mental models.
Collaboration skills-based multimedia-based integrated instruction (CS–MBI2): a development study on refraction concept
Authors: Setiawan Y C , Samsudin A , Suhendi E , Novia H , Kaniawati I , Chandra D T , Siahaan P
Published: November 2019

Development of physics interactive multimedia is still rarely found, especially regarding to collaboration skills enhancement. This study is having a purpose to develop a Multimedia-Based Integrated Instruction (MBI2) that expected to define student’s collaboration skills profile. Researcher uses Sadiman’s model of development research method which consists of identifying students need, formulating instructional objective, formulating learning materials, developing evaluation instrument, producing, and revising. As a research sample, thirty-three eight grader students in Bandung are being involved in this study. Result shows each profile of student’s collaboration skills respectively 3.30; 3.06; 3.82; and 2.70 (by maximum student’s achievement score of 4). It can be concluded that development of Multimedia-Based Integrated Instruction (MBI2) research is capable for defining junior high school student’s collaboration skills profile on refraction concept.
Improved problem-solving skills of the student through cooperative problem-solving models related to fluid dynamic topic
Authors: Malik A , Kumala W , Mulhayatiah D , Aliah H , Darmalaksana W , Setiawan A , Chusni MM , Dirgantara Y , Agustina RD , Rochman C , Hermita N , Samsudin A
Published: November 2019

Problem-solving skills (PSS) were needed to prepare for the working world. Based on a preliminary study at one of Senior High School in Banjaran West Java, the average score of student Problem-Solving Skills (PSS) was low. This study aims to determine the improvement of PSS of student after applied Cooperative Problem Solving (CPS) models on dynamic fluid. The research method used was a pre-experiment with one group pretest-posttest design. The subjects of this study were students of class XI Science 2 selected by purposive sampling technique amounted to 30 people. The student’s PSS was measured through an essay test and a supporting instrument in the form of student worksheets. The results showed that there was an increase of PSS of students with  of 0.68 medium categories. Based on the paired sample t-test where tcount (12.24) > ttable (2.05) indicates that there was the influence of CPS models to improve PSS of students. The average results of the student worksheet analysis indicate that there was an increase student’s PSS at each meeting and the average value was categorized well. Thus, the CPS models can be used as an alternative learning model that can improve PSS of students on dynamic fluid.
Development and implementation of creative, solutive and smart teaching (CS2T) to improve 21st century capability on wave and optics
Authors: Syaodih E , Suhandi A , Maftuh B , Hermita N , Fratiwi N J , Samsudin A
Published: November 2019

The aim of this research was to develop and implement Creative, Solutive and Smart Teaching (CS2T) to improve 21st century capabilities on wave and optics. The CS2T is a learning approach that encompasses clusters of students employed collected to elucidate a problematic, comprehensive assignment, or produce a creation. We have already utilized the ADDIE model (Analysing, Designing, Developing, Implementing and Evaluating) as a research method. The samples are 37 students (15 boys and 22 girls, their ages were an average of 18 years old) at one of the primary educations in the West Java province of Indonesia on wave and optics topic. The improvement of 21st century capabilities has been diagnosed through a creative thinking instrument (CTI), problem solving test (PST) and observation sheet (OS). In the evaluating phase, the CS2T is able to improve student’s capabilities in employed collected and improve the realization of learning effects. In conclusion, primary students’ skills are able to be improved through CS2T on wave and optics topic.
Implementation of STEM education in Indonesia: teachers’ perception of STEM integration into curriculum
Authors: Suwarma I R , Kumano Y
Published: November 2019

Recently in America, Europe and Asia, STEM education has been viewed as an educational reform that answers 21st-century demands in an era of productive technology and information that trigger economic, political and demographic changes around the world. As a developing country, Indonesia is called upon to deal with these demands by developing qualified human resources through educational reform. STEM education is one of the strategies for achieving this goal. Finding possibilities for the integration of STEM in the science and math curriculum through teacher training programs is the first step in this implementation, whether or not STEM education can actually be included. This study took place in a school that uses two curricula (KTSP and the 2013 national curriculum). Results of an investigation of teachers’ perceptions showed that the 2013 national curriculum was more appropriate for the inclusion of STEM education than the KTSP curriculum. The impact of training on teachers’ perceptions was shown by significant differences before and after training.
An investigation of conceptual understanding ability K-11 student of linear motion
Authors: Dewi E , Muslim  , Samsudin A
Published: November 2019

Identification of conceptual understanding is an important first step in order to learning 21st skill. Understanding concepts is the fundamental ability of students to achieve high order thinking skills. Thus, the student has ability to better acquire a knowledge when learning of high order thinking. The purpose of this study is determining the conceptual understanding ability of the grade 11th in high school. This study has been implemented through a single case study research. Participant in this study are 36 students from a senior high school, consists of 22 female and 14 male students. The instrument used in this study is a test of the ability to understand concepts with multiple choice questions as many as 15 questions. The low ability to understand students’ concepts in each indicator with the percentage for indicators exemplifies (72.22%), describes the conclusions (55.56%), interprets (41.67), compares (47.22%), explains (57.64%) determines (72.22%) and classify (61.11%). The result from the study, the student in grade 11st are low ability of concept understanding ability.
Is integrating earth and space sciences (ESS) with art contexts necessary?
Authors: Putri M P , Liliawati W , Samsudin A , Hasanah L
Published: November 2019

The study aims to obtain facts related to the process of implementing Physics learning on Earth and Space Sciences (ESS) subject in Bandung area. This study has been conducted to 125 twelfth graders and 3 teachers from three high schools in Bandung area through a survey method with questionnaire fulfilment. The results state that the student interest, self-attraction and agreement of integrating ESS subject with other subjects are positively response. On the other hand, the learning should be improved. Physics learning requires the involvement of students in finding their own knowledge through interaction with their environment. However, students stated that the perceived obstacle in ESS learning was the lack of involvement of students in learning. In conclusion, ESS is important to integrate with art context for developing several aspects. Furthermore, ESS developing process is needed to help teachers bring their classes in a more interesting, effective and innovative way.
Needs analysis of web-based earth and space science learning materials for high school students
Authors: Zulika A M , Liliawati W , Ramalis T R , Utama J A , Samsudin A
Published: November 2019

The purpose of this study analyses needs of learning materials on Earth and Space Science for high school students. Earth and Space Science is one of the subjects taught in Physics. Often, the implementation of earth and space science learning is not conveyed and rarely available in other subject. The survey method has been utilized with questionnaires in three high schools around the Bandung zone. The number of respondents is 158 high school students and 3 high school teachers. The data has been obtained that earth and space science is more interesting if the learning materials was available. High school students often access the internet in term of collecting alternative learning resources beside teachers teaching. In conclusion, the researchers intend to develop web-based teaching materials for high school students. This web-based learning material for high school students has been developing.
Capacity Credit Algorithm and Index of the New Energy of Wind Energy and Solar Energy based on Big Data
Authors: Wei Wang , Wenguang Zhu , Hong Cheng , Ning Xiong , Liping Peng , Yifan Zhang
Published: November 2019

Since twenty-first century, many countries have accelerated their development, and the energy on the earth has been gradually consumed, which not only has caused the lack of energy, but also the environmental pollution. Therefore, people have paid much attention to the related problems. Based on the research of big data theory, the credibility algorithm of new energy was established in this paper. And through the establishment of wind farm power generation model, its reliability and indicators were analyzed. Thus, the feasibility of replacing old energy with new energy sources was explored. And through the analysis of the data, the reliability of wind farms and photovoltaic power plants was evaluated.
Micro-Mismatch Loss Analysis Based on Solar Cell IV Curve
Authors: Wang Lei , Liu Fuguang , Zhang Zhen , Shao Xi , Zhu Zengwei , Deng Shifeng
Published: November 2019

Solar cells are usually connected in series and parallel to meet the voltage and current requirements for application. Shadows on the surface of C-Si (crystalline silicon) solar cell modules lead to the mismatch of current and voltage between the cells, which is one of the main causes of output power loss. In this paper, an approximate calculation method based on IV curve model is introduced. The micro-mismatch is defined as the ratio of current mismatch is less than (ISC – Im
)/ISC
, usually less than 6%. According to calculation and experiment result, power losses caused by solar cells micro mismatch of Imp, Pm, Vm, FF in solar module were analyzed. The result shows that the introduced method can simulate the micro mismatch effect of solar cell application. The module power loss is not obvious, when cell matching is less than 1.5%. When the cells current mismatch is 5%, the influence of module power output is less than 1%.
Research and Practice on Course Design of Medical Physiology and Engineering under the Background of Cultivating Innovative Talents
Authors: Yingjiu Liu , Ning Li , Xinying Li , Fei Chen , Tianyao Wang , Rui Pang
Published: November 2019

This paper takes the medical electronics foundation course of medical imaging as an example., Through the introduction of four typical circuit design requirements and design methods, discusses the purpose and significance of increasing the course design of medical physiological engineering courses under the background of cultivating innovative talents., The method of curriculum design in medical courses, the main problems to be solved and the specific design scheme and results. According to the task and design index requirements of the selected topic, students determine the requirements of the overall design scheme, and draw the system block diagram of the overall scheme (pre-design stage); Analysis, input design, compilation and simulation of the underlying unit circuit; Draw the schematic diagram of the top circuit with the correctly compiled module of the bottom unit, and carry out compilation, debugging and simulation test. Write design report. Through course design, students can learn to search information, compare schemes, calculate circuit parameters, design circuit schematic diagram, make printing board, weld and debug components, test circuit performance, so as to improve students’ ability to analyze and solve practical problems. After the completion of the overall design, select the right device, apply the design scheme, complete the circuit board production, one step in place. At the same time, virtual and real contrast.
On the Necessity to Integrate Power Flexibility in Cooling Systems
Authors: Vuarnoz D , Niederhäuser E-L , Torregrossa D. , Gabioud D
Published: November 2019

Today, cooling systems are widely used, notably with the unprecedented growth of data centres and building space cooling. These thermodynamic systems are powered mainly with electricity, and their peak loads are generally associated with very high carbon footprints. At the same time, congestion of the grid due to high load or renewable power injection is becoming an issue for all actors involved with electricity (producers, providers, consumers, and prosumers). Actually, both the price and associated carbon footprint of electricity usually fluctuates along with the charge of the network. This paper discusses the integration of power flexibility (PF) in new and existing cooling systems to avoid a possible cold crunch in the near future. After defining PF, several cooling systems archetypes are presented. Three possible ways to integrate PF are explained: flexibility by thermal inertia and energy storage (thermal and electrochemical). While PF principally targets the reduction of stress on the electric grid, other benefits can also be achieved, e.g. mitigation of direct carbon emissions and decrease of costs related to operating the refrigeration system. We explain how better management of energy transits and possible imbalance in electricity networks can be achieved by thermal inertia. The choice of integrating thermal storage or electric battery is discussed, and both solutions are considered in a specific case study. The study aims at better management of power loads on electricity network caused by the cooling system and could be useful for anyone involved with grid management and/or refrigeration systems.
Research on Power Data Management Based on Sovereign Blockchain Technology
Authors: Wang Huayun , Li Qiong , Huang Hong , Qu Haoyue , Wang Wenbing , Meng Tianqi
Published: November 2019

The development of smart grid technology has improved the way in which grid companies interact with power users, but there are data breaches when data falls into the hands of malicious attackers. This paper implements a multi-blockchain system based on sovereign blockchain technology for the main body of the power trading market, and designs the data transmission mechanism and system architecture. Through the power data classification index, the effective mining and utilization of intelligent power data is realized. Incorporating national sovereignty constraints into smart contracts ensures that smart grids provide a system of trusted, nationally compliant systems for power users’ electricity transactions. Finally, the advantages of the power data management scheme proposed in this paper are analysed by comparing with the traditional power data management methods.
PSO-based Siting and Sizing of Electric Vehicle Charging Stations
Authors: Chen Han , Nie Jin , Ye Bichao
Published: November 2019

With the rapid growth of the number of electric vehicles, the optimization of charging network is imminent. In this paper, a screening method for the siting and sizing of electric vehicle charging station is developed to minimize the total cost including capital investment on stations, EV charging stations’ operation cost and maintenance cost. Driving distance of electric vehicles and service radius of stations are taken into account to pick out the optimal sites of EV charging stations. A mathematical model with electric physical constraints is designed to distribute appropriate capacities for each EV charging station to prevent the negative effects on the power grid and the PSO optimization algorithm is applied to obtain the optimal sizing parameters. Finally, the IEEE 123-bus test feeder case study is used to confirm the validity of the proposed method and increase the economic benefits.
An Improved Variable Step Size P&O MPPT Algorithm Based on Constant Voltage and K Division Technology
Authors: Peng ZHANG , Huibin SUI , Hongmei KONG
Published: November 2019

In the literature, various techniques have been proposed to achieve the maximum output power of photovoltaic cells, but the fixed step size perturbation and observation and incremental conductance algorithm can’t enhance effectively the peculiarity of the PV system, due to their slow tracking speed, big power loss and limited accuracy. An improved variable step size perturbation and observation MPPT algorithm based on the K division method is proposed. The symbol of dp/du before and after the disturbance is judged, if the two adjacent samples have the same symbol, the disturbance step size remains unchanged. On the contrary, the disturbance step size will be divided by K and become the new disturbance step size until achieving the maximum output power. The simulation establish on MATLAB/Simulink reveals that the method has fast response speed, high accuracy, low power loss, and can locate the new maximum power point quickly when environmental conditions change.
Two-stage Planning of Integrated Energy System Considering Investment Flexibility
Authors: Qiu Yue , Ying Xiaolei , Pei Chuanxun , Fang Yunhui , Yue Feng , Zhou Suyang , Gu Wei
Published: November 2019

The Integrated Energy System (IES) can optimize the utilization of various forms of energy and effectively alleviate the problems of energy exhaustion and environmental pollution. A two-stage planning model of IES that considers the uncertainty of renewable energy and the flexibility of investment is proposed in this paper. The planning period is divided into two stages in terms of varying degrees of uncertainty based on Monte Carlo simulation. In terms of economic, technical, and environmental performance, the two-stage planning method is proved to be better than conventional single planning method. The proposed algorithm shows the superiority of multi-stage planning. In addition, it can be used for the planners to comprehensively analyze and compare the optimal decision-making schemes generated by different combinations of weight factors.
Experimental study of critical heat flux at flow boiling of R125 in small diameter channel
Authors: Zanosko A I , Dedov A V , Belyaev A V
Published: November 2019

This paper presents an experimental setup and experimental data for critical heat flux at high reduced pressures. Studies on critical heat flux during the forced flow of Freon R125 in a vertical channel with a diameter of 0.95 mm and length of 100 mm were performed. The hydraulic loop of the setup provides stable flow conditions at the inlet of the test section under pressures up to 2.5 MPa and temperatures up to 200 °C. The measured parameters were the mass flow rate, pressure and temperature at the inlet and outlet of the test section, the joule heating power and the wall temperature in the six cross-sections along the tube. An automated data-acquisition system was used during the experiments. A comparison between the experimental and calculated data is presented.
Influence of space plasma on the work of the liquid droplet radiator
Authors: Safronov A A , Filatov N I , Grigoryev A L , Bondareva N V
Published: November 2019

The effect of the charging of the droplet flow, resulting from the interaction of dispersed particles with space plasma, on the work of low-potential liquid droplet radiator has been studied. The critical value of the particle charge at which the curvature of the particles trajectories is unacceptably large is determined. The dynamics of charged droplet flow is investigated; its vibration stability is analyzed. A model for the electrification of free-circulate droplet flow is proposed. The results of numerical calculations of the electrification and distribution of droplet flows are given.
Electrical conductivity of aqueous solution of KOH at atmospheric pressure
Authors: Kuznetsov K I , Skorodumov S V , Granchenko P P
Published: November 2019

Measurements of the electrical conductivity ratio of a 20% aqueous solution of KOH depending on temperature, intensity of electric field and frequency of changing direction of current are being studied. To ensure and conduct the measurements a conductivity meter was made with a current that changed the direction by means of a “meander” voltage. The measurement results of the study are processed in the form of analytical dependencies.
Experimental study of transient processes in a Glow Discharge
Authors: Yunusov R F , Garipov M M
Published: November 2019

The article experimentally investigated the features of a glow discharge with a hollow cathode in a longitudinal air flow. The discharge chamber consisted of glass sections separated by copper plates serving as probes. The channel formed by such sections and probes had a cylindrical shape. Air flowed through the hollow cathode into the cylindrical channel. The anode served as a metal grid. Probes and electrodes were made of copper. The distance between the electrodes was 6.5 cm. The air pressure P, its speed V, the discharge current I and its voltage U changed respectively in the ranges: P = (6, 4 - 19) kPa, V = (0 - 10) m / c, I = (5-100) mA, U = (1, 0 - 2, 2, 0) kV. Volt-ampere characteristic had negative differential resistance. It was found that in the range of discharge currents I = (40-80) mA, the forward and reverse branches of the current-voltage characteristics do not match. When the current decreases (reverse branch), the discharge voltage rises sharply. This is due to the process of transition of a glow discharge into its non-stationary form, which was observed visually and was recorded photographically for all the characteristic modes of discharge. It was also shown that the flow of air allows a reverse transition to the usual form of discharge.
On accelerative mechanism of nuclear fusion in the Sun
Authors: Oreshko A G
Published: November 2019

An explanation of an existence of sunspots on the surface of the photosphere is given. They are caused by the presence of current-plasma channels between the surplus negatively charged nucleus and the surplus positively charged photosphere of the Sun. In current-plasma channels and in prominences that appear during electrical breakdown between electric islands on the surface of the photosphere, electrical domains are generated due to presence of runaway electrons. The generation of electrical domains accompanied by the generation of transverse electromagnetic waves. Charged particles in the electromagnetic wave field gain energy that is sufficient to overcome the Coulomb potential barrier.
Reduction thermal resistance methods in the thermal stabilizer
Authors: Kuzma-Kichta Yu A , Ivanov N S , Lavrikov A V , Shtefanov Yu P , Prokopenko I F , Skvortsov P I
Published: November 2019

The thermal resistance of the composite thermal stabilizer and methods for its reduction are investigated. The thermal resistance of thermal stabilizer decreases due to the heat exchange intensification in evaporator by a layer of aluminum oxide nanoparticles. A method of producing aluminum oxide nanoparticles has been developed. The liquid capillary rise height is measured in the layer of nanoparticles. Estimate of the properties stability is obtained in the coating from aluminum oxide nanoparticles. The thermal resistance dependences are obtained on the transferred heat flux for models of thermal stabilizers from steel and aluminum
Q-switching Zirconia-Erbium-doped Pulsed Fiber Laser with MWCNTs-PEO as Saturable Absorber
Authors: Markom Arni Munira , Ahmad Muhammad Taufiq , Haris Hazlihan , Muhammad Ahmad Razif , Yusoff Zakiah Mohd , Burham Norhafizah , Paul Mukul Chandra , Dhar Anirban , Das Shyamal , Pal Mrinmay , Bhadra Shyamal Kumar , Harun Sulaiman Wadi
Published: November 2019

Q-switched pulses provide a significant contribution to recent biomedical applications such as laser treatment, medical imaging, biomedical diagnoses and spectroscopy due to high efficiency, compact device, less footprint, flexibility and cost effective. A successful generation of Q-switching pulsed fiber laser by using a homemade fiber of zirconia-based erbium-doped fiber (Zr-EDF) with the utilization multi-walled carbon nanotubes-polyethylene oxide (MWCNTs-PEO) as saturable absorber is reported. The active medium is 1 meter length of Zr-EDF with -0.6 ps2 group delay dispersion (GDD) for overall setup arrangement. At maximum pump power 126 mW, the repetition rate, pulse duration, output power and pulse energy are 17.3 kHz, 7.57 μs, 1.13 mW and 65.03 nJ, respectively.
A Study of Informative EEG Channel and Brain Region for Typing Activity
Authors: Bin Ng Wei , Awang Saidatul Ardeenawatie , Fook Chong Yen , Chin Lim Chee , Ying Ong Zhi
Published: November 2019

Electroencephalography (EEG) is an electrophysiological monitoring method to record electrical activity of the brain. Brain consists of four lobes which is frontal, parietal, temporal and occipital lobe. Each lobe has their own respective function and it release different rhythmic wave when carry out different actions. However, when performing a specific activity, not all the EEG channels tend to be informative to the particular activity. The need to optimize the number of channels is crucial to reduce computational complexity. The aim of this paper is to determine the informative EEG channel/s and brain region for typing activity. 20 healthy with right-handed subjects from Universiti Malaysia Perlis (UniMAP) were enrolled in this study. Typing task was performed for 3 trials and 5 minutes per trial. In EEG signal processing, Notch filter and Butterworth bandpass filter were used to remove powerline artefact and to filter the signal into alpha (8-13Hz) and beta waves (13-30Hz). Welch method was applied to extract features from typing task. The obtained results were then undergoing the statistical analysis before load into the K-Nearest Neighbour (KNN) and Linear Discriminant Analysis (LDA) classifier. Based on this study, it is found that channel P3 in parietal region and channel T6 in temporal region give highest accuracy which is 99.44% for typing task activity.
Effect of swelling agent on pore properties of mesoporous carbonated hydroxyapatite
Authors: Mohammad Nur Farahiyah , Amiruddin Nadia Liyana , Saleh Siti Shuhadah Md , Taib Mustafa Ali Azhar , Nasir Nashrul Fazli Mohd
Published: November 2019

Mesoporous carbonated hydroxyapatite (CHA) has been seen to be suitable as an adsorbent material due to the proven biocompatibility, bioactivity and chemical stability. However, obtaining the high surface area and desired pore size for mesoporous materials become the main challenge in producing good quality adsorbent materials. Thus, this study aims to investigate the effect of addition of swelling agents on pore properties of mesoporous CHA. Mesoporous CHA was synthesised by precipitation method. Triblock co-polymer, P123 surfactant was used as a soft template to introduce pores within the CHA particles and 1-dodecanethiol as a swelling agent. Two different mixing temperature (60°C and 80°C) were used during the mixing process of P123-calcium solution and 1-dodecanethiol. The effect of different mixing temperature (60°C and 80°C) and various concentration of swelling agent on the phase, morphology and pore characteristics of mesoporous CHA were investigated using various material characterization techniques. Mixing temperature 60°C, produced mesoporous CHA with much higher surface area (92.8 m2/g), larger pore size (22.9 nm) and higher pore volume (0.502 cm2/g) than those produce at 80°C (surface area = 62.7 m2/g, pore size = 2.6 nm and pore volume = 0.105 cm2/g). The highest surface area (146.9 m2/g) of mesoporous CHA was obtained when there was no swelling agent added. However, the pore size of the sample was very small. Therefore, the optimum pore characteristics (surface area = 104.5 m2/g, pore size = 24.4 nm and pore volume = 0.530 cm2/g) of mesoporous CHA was obtained when the swelling agent concentration is 0.6 M and the mixing temperature is 60°C. Both mixing temperature and swelling agent concentration have profound effect on the pore characteristics of mesoporous carbonated hydroxyapatite (CHA).