Journal of Physics: Conference Series

The implications of online learning versus face-to-face learning have been discussed for several years in higher education. This study examined the issues of student perception toward online learning and face-to-face learning in the context of social presence, social interaction, and satisfaction in Indonesia Open University, Taiwan branch (n = 107). The comparison of the online group and the face-to-face group conducted to explore student-learning perceptions regardless of the course delivery method and the online environment. The result of this study indicate that face-to-face learning perception was higher than online learning in term of social presence, social interaction, and satisfaction. However, there is no statistically significant difference in learning preference found among level of student. Meanwhile, some students were very comfortable in online learning since it led them to the chance to being innovative by using computer technology.

The article considers the positive and negative aspects of the use of electric vehicles. A rough calculation of the energy efficiency and average cost per month was made. Also priorities to avoid the existing problems in the market of electric vehicles were set.

Abstrac. A fast method presented within this paper to find transparent liquid viscosity. An introduced tracking algorithm in image processing used to find a terminal velocity automatically of a falling ball in a tube that filled with a tested liquid. Terminal velocity considered an important parameter to find a liquid viscosity. Therefore, four iron balls, with different diameters and a smartphone camera are used to measure the falling ball terminal velocity. The estimated velocity from the introduced algorithm is compared with the calculated velocity and shows a good matching. The second algorithm used to estimate the viscosity of the tested liquid. The limitation of the ball diameter around 5mm to measure the terminal velocity. The result shows error matching between the fitting data and the estimated data ranging (0.00-0.1%). This method is a faster and easier experiment to use to find any transparent liquid viscosity comparing with a viscometer.

Time management is very important and it may actually affect individual’s overall performance and achievements. Students nowadays always commented that they do not have enough time to complete all the tasks assigned to them. In addition, a university environment’s flexibility and freedom can derail students who have not mastered time management skills. Therefore, the aim of this study is to determine the relationship between the time management and academic achievement of the students. The factor analysis result showed three main factors associated with time management which can be classified as time planning, time attitudes and time wasting. The result also indicated that gender and races of students show no significant differences in time management behaviours. While year of study and faculty of students reveal the significant differences in the time management behaviours. Meanwhile, all the time management behaviours are significantly positively related to academic achievement of students although the relationship is weak. Time planning is the most significant correlated predictor.

The document is a collection of written or printed data containing information. The more rapid advancement of technology, the integrity of a document should be kept. Because of the nature of an open document means the document contents can be read and modified by many parties so that the integrity of the information as a content of the document is not preserved. To maintain the integrity of the data, it needs to create a mechanism which is called a digital signature. A digital signature is a specific code which is generated from the function of producing a digital signature. One of the algorithms that used to create the digital signature is a hash function. There are many hash functions. Two of them are message digest 5 (MD5) and SHA256. Those both algorithms certainly have its advantages and disadvantages of each. The purpose of this research is to determine the algorithm which is better. The parameters which used to compare that two algorithms are the running time and complexity. The research results obtained from the complexity of the Algorithms MD5 and SHA256 is the same, i.e., ⊖ (N), but regarding the speed is obtained that MD5 is better compared to SHA256.

Assessment of discriminant validity is a must in any research that involves latent variables for the prevention of multicollinearity issues. Fornell and Larcker criterion is the most widely used method for this purpose. However, a new method has emerged for establishing the discriminant validity assessment through heterotrait-monotrait (HTMT) ratio of correlations method. Therefore, this article presents the results of discriminant validity assessment using these methods. Data from previous study was used that involved 429 respondents for empirical validation of value-based excellence model in higher education institutions (HEI) in Malaysia. From the analysis, the convergent, divergent and discriminant validity were established and admissible using Fornell and Larcker criterion. However, the discriminant validity is an issue when employing the HTMT criterion. This shows that the latent variables under study faced the issue of multicollinearity and should be looked into for further details. This also implied that the HTMT criterion is a stringent measure that could detect the possible indiscriminant among the latent variables. In conclusion, the instrument which consisted of six latent variables was still lacking in terms of discriminant validity and should be explored further.

As one of the most important power sources in modern society, electricity takes up a large proportion of modern energy consumption. Among all those methods of power generation, fossil-fuel thermal power generation is one of the earliest ways of large-scale electricity production. Its popularity in the modern society comes from its stability and controllability. Given the wide applications of electricity around the world, improving the efficiency of thermal power plants would be an effective way to reduce the total energy consumption and protect the environment. The paper discusses the efficiency of energy transition and its determinant during each stage of power generations along with proposals to improve the efficiency of thermal power generation.

Prediction using a forecasting method is one of the most important things for an organization, the selection of appropriate forecasting methods is also important but the percentage error of a method is more important in order for decision makers to adopt the right culture, the use of the Mean Absolute Deviation and Mean Absolute Percentage Error to calculate the percentage of mistakes in the least square method resulted in a percentage of 9.77% and it was decided that the least square method be worked for time series and trend data.

This study aimed to produce a model of scientific attitude assessment in terms of the observations for physics learning based scientific approach (case study of dynamic fluid topic in high school). Development of instruments in this study adaptation of the Plomp model, the procedure includes the initial investigation, design, construction, testing, evaluation and revision. The test is done in Surakarta, so that the data obtained are analyzed using Aiken formula to determine the validity of the content of the instrument, Cronbach’s alpha to determine the reliability of the instrument, and construct validity using confirmatory factor analysis with LISREL 8.50 program. The results of this research were conceptual models, instruments and guidelines on scientific attitudes assessment by observation. The construct assessment instruments include components of curiosity, objectivity, suspended judgment, open-mindedness, honesty and perseverance. The construct validity of instruments has been qualified (rated load factor > 0.3). The reliability of the model is quite good with the Alpha value 0.899 (> 0.7). The test showed that the model fits the theoretical models are supported by empirical data, namely p-value 0.315 (≥ 0.05), RMSEA 0.027 (≤ 0.08)

The refractive index in the bent fibre optics and in curved space of the gravitational field are studied. We obtain the results that refractive index in the bent fibre optics is similar with refractive index in curved space of the gravitational field. Both results show that refractive index increases when light traverses through the bent fibre optics and curved space of the gravitational field. Based on analogy reasoning taken from fibre optics bending loss phenomena, we propose that if light traverses through curved space of the gravitational field, light will loss its energy. We calculate this energy loss numerically using bending loss model of Faustini-Martini. We find that light losses its energy around 467.7073 dB/m, when it traverses through curved space with radius of curvature R = 0.01 m due to massive object around 8.7 × 10 ²⁰ kg.

In this research work the classification of defects of castings obtained by electric arc smelting is considered. Of particular interest to researchers is the rock-like and naphthalene fractures. A stone-like fracture is characterized by a clearly defined uniform surface over which the fracture occurs. Grain boundaries are partially soluble in the austenite phase, consisting of fine individual particles or films formed from molten eutectics. It is also worth noting that most often the stone-like fracture is observed at the grain boundaries.

The article is devoted to the issues of transition of the Russian electric power industry to renewable energy sources. The analysis carried out in the work showed that in the electric power industry there has been a tendency to intensify activities to switch to innovative and renewable technologies in the production of electric energy. The main goal of the transition is to reduce the use of depleted natural resources and reduce the environmental burden. A similar trend is associated with the need to increase the competitiveness of the Russian electric power industry, since in some countries of the world up to 25% of electric energy is generated from renewable energy sources. In addition, in recent years, state programs have been adopted in which by 2024 it is planned to increase installed capacity based on renewable sources to 11 GW. At the end of the work, a structural-logical scheme was proposed that allows for the transition from traditional energy to renewable energy sources. In conclusion, the study presents the main findings and results of the work.

During the work considered questions of the occurrence of cavitation in hydro abrasive flows, which can lead to a rather complex phenomenon that is difficult to understand the essence of this process. Today, the wear of the working bodies of centrifugal and axial pumps, depending on the mode of their operation has not been learned much, and there has been developed a technique for selecting operating modes, taking into account the wear of their parts. Also, the results of complex laboratory and field studies on the intensity of wear of the flow elements of centrifugal and axial pumps are presented. It has been established that the alternating, pulsating load leads to an increase in the force of interaction of the hydro abrasive flow with the camera surface and increases its wear by 10 %, and also reduces the capacity of the pumping unit to 9%.

The article contains an optimization analysis of the patterns of formation of a set of parameters with all the constraints affecting, which revealed the economic feasibility of using a limited number of cable sections used. With the help of the criterion analysis method, the economically reasonable values of the parameters being optimized are determined and recommendations are made on the use of the obtained optimal parameters for distribution electric networks.

The article is devoted to the development of digital technologies in the electric power industry of Russia. It is proved in the work that in recent years the issues of the industry’s transition to a qualitatively new development path, which, according to the authors of the study, should be based on the introduction of digital technologies and smart grids in the electric power industry, have become relevant. The study presented the main advantages of the Smart Grid system, which are self-regulation of the electric power industry and maintaining stability and reliability in the long term. At the same time, it was revealed that the transition to digital technologies requires the industry to form a new asset and production unit management system related both to the superstructure and the creation of new energy complex management elements. At the same time, it is expected that the introduction of Smart Grid will increase the economic, environmental, social and technological effect both for the industry and for the national economy as a whole. At the end of the study, conclusions are drawn from the results of the work done.

Next generation accelerators demand sophisticated beam sources to produce ultra-low emittances with large gradients. The subsequent beamline optics are equally critical to transporting these beams between accelerating stages or to interaction points. Capillary discharge plasmas may address each of these challenges. Capillaries have been demonstrated as sources capable of increasing the peak energy and beam quality of laser wakefield accelerators, and as active plasma lenses featuring orders-of-magnitude increases in peak magnetic field. These systems are sensitive to energy deposition, heat transfer, ionization dynamics, and magnetic field penetration; therefore, improved modeling will enable advances in capillary design. We present simulations of capillary discharge waveguides and active plasma lenses in using FLASH, a publicly-available multi-physics code in development at the University of Chicago. We report on the implementation of a 2D, cylindrically symmetric capillary model for capturing plasma density and temperature evolution with realistic conductivities and magnetic fields. We then illustrate the use of laser energy deposition to model low density channel formation for the matching and guiding of intense laser pulses. Lastly, we discuss simulations of active capillary plasmas with different fill species, which show agreement with experimental observations of nonlinearities in the current density profile and magnetic field.

List of Preface, Committee member, Co-Chairmen, Organizing Committee, Technical Committee and all this titles are available in this PDF.

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

☐ Type of peer review: Single-blind / Double-blind / Triple-blind / Open / Other (please describe) Double-blind

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☐ Conference submission management system: https://www.ais.cn/attendess/index/U6JA7B

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☐ Number of submissions received: 278

☐ Number of submissions sent for review: 235

☐ Number of submissions accepted: 117

☐ Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100): 42.1%

☐ Average number of reviews per paper: 2

☐ Total number of reviewers involved: 62

☐ Any additional info on review process:

☐ Contact person for queries: shunwing.n@outlook.com

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According to the principle of ultrasonic phased array inspection, the ultrasonic phased array inspection simulation experiment is carried out on the butt weld of small diameter tube of power plant boiler by using the Ultravision software, which mainly includes the simulation of acoustic beam coverage and focused beam distribution. From the simulation test results, it can be concluded that: through the simulation of the acoustic beam coverage, the accessibility and coverage of the ultrasonic phased array acoustic beam can be simulated, and the applicability of the detection process can be verified and optimized; Through the simulation of focusing beam distribution, the distribution of the beam focus in the butt weld of the small diameter tube can be determined, which can guide the selection of focusing mode in the detection process and improve the signal-to-noise ratio of defect detection.

In the analysis of power market economic evaluation indicators, it is more common to use technical data mining for data calculation based on technology maturity analysis. This paper is based on a distributed computing platform for data mining, and parallelizes the traditional FP-Growth algorithm, so that the FP-Growth algorithm can be applied to the mining of big data association rules. Experimental results show that the algorithm can greatly improve the efficiency of mining association rules for massive data. The model is trained and tested on a distributed cluster built into the laboratory using customer electricity data, and then the predictions are validated to determine whether the difference between the predicted values and historical data for the same period exceeded the set threshold.