bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of ball-milling time on chemical property of coconut shell powder
Authors: Ismail I , Arliyani  , Fathmiyah S , Mursal  , Jalil Z , Khalil H P S A 
Published: July 2020

Abstract
Coconut is one of the abundant agricultural products in Indonesia. Coconut shell is one of the wastes from coconut products that can be used as biocomposite material. The purpose of this study was to find out the effect of ball milling time on the chemical properties of coconut shell powder. X-ray diffraction (XRD) and X-ray fluorescent (XRF) have been used in this study. Coconut shell powder 200 mesh was milled using mechanical ball milling for various milling times (20, 30, and 40 hours) at 350 rpm constant speed. The results of our study using XRD showed that the coconut shell powder contains SiO2, C, Fe2O3, CaO, K2O, and Al2O3. The intensity of the diffraction pattern from our sample increased when the ball-milling time was increased. This implies that the crystallinity of the sample was influenced by the ball-milling time. By using XRF, it was found that the coconut shell powder contains 13.6% of Fe2O3, 25.7% of CaO, 46.1% of K2O, 2.8% of CuO, and 8.2% of P2O5. The percentage composition of Fe2O3 increased from 13.6% for 0 hours milling time to 30.2% after the sample was milled for 20 hours. The percentage composition of Fe2O3 rose to 32.2% for the milling time of 40 hours. However, the percentage compositions of CaO and K2O decrease as the milling time is increased. The percentage composition of P2O5 is independent of milling time. Our results show that the chemical properties of coconut shell powder are influenced by the ball-milling time or particle size of coconut shell powder.
Effectiveness of the implementation of probing-prompting learning model on student learning outcomes in the discussion of static fluid
Authors: Lutfia A , Asyhari A , Saidy  
Published: July 2020

Abstract
This study aims to determine the effectiveness of the Probing-Prompting learning model on student learning outcomes. To see student learning outcomes, researchers use a test in the form of multiple-choice questions. This research is to know the effectiveness of the learning model Probing Prompting towards the Learning Outcomes of students in the static fluid material class XI IPA SMAN 1 Sukadana 2018/2019 school year. This research is a quasi-experimental research. This study uses two classes as an experimental class and one class as a control class. The sampling technique used was purposive sampling. The research sample is by choosing a class that is contained in class XI MIA, which has low learning outcomes. Then the researchers gave treatment to class XI MIA 2 as an experimental class by applying the learning model Probing Prompting in learning, and class XI MIA 1 as a control class applied to the learning model in Discovery Learning accordance with the habits of educators. To find out the differences in learning outcomes in the control class and the experimental class a t-test was conducted using the Polled Variance formula. The results of the analysis of learning outcomes show tcount = 9.51 while ttable = 2.01 so that tcount>ttable, and H1 received. The learning model is Probing-Prompting more effective in improving student learning outcomes, and effectiveness can be seen with the effect size test. The results of the test Effect size are, therefore, included in the medium category (d = 1,021 <0.8). Based on these results, it can be concluded that the learning model is Probing Prompting effective in improving student learning outcomes.
Identification of students’ misconceptions using the Certainty of Response Index (CRI) from work and energy material
Authors: Mustari M , Anggereni S , Sodikin  , Fitria  , Yusandika A D 
Published: July 2020

Abstract
Research has been conducted at SMAN 1 Pesisir Selatan aimed to determine the level of students’ misconceptions on work and energy materials. This research is quantitative descriptive with students from class X MIPA 2 SMAN 1 Pesisir Selatan as objects. The sampling in this study uses purposive sampling method. The data also is analyzed quantitatively. The results shows that the students’ misconception level is 13.11% in which the criteria for the level of misconception is low.
Magnetic properties of Ga-doped and As-doped hydrogenated silicene: Density Functional Theory (DFT) calculations
Authors: Pamungkas M A , Sari F , Abdurrouf  , Nurhuda M 
Published: July 2020

Abstract
Computational studies of silicene, which is a two-dimensional silicon material with honeycomb structure, has been carried out using Density Functional Theory Calculation. This study was aimed to determine the effects of doping gallium (Ga) atom and arsenic (As) atom on the magnetic properties of hydrogenated silicene. The results showed that pure silicene has very small magnetic properties, can be considered as non-magnetic. The process of hydrogenation on silicene changes it to become a magnetic material. The effects of Ga/As dopant on the magnetic properties of hydrogenated silicene depends on positions of Ga/As atom. Silicene with As atom at hollow site has the highest magnetic moment of 0.0592 μB
. This value increases from the magnetic moment of hydrogenated silicene magnet by 104%.
Simulation of physical activities effect and treatment exogenous insulin for managing plasma glucose concentration in type 1 diabetes mellitus
Authors: Kartono A , Sari M , Wahyudi S T 
Published: July 2020

Abstract
The simulation model of glucose level dynamics system during physical activity is important to represent an actually of the normal living conditions. These simulation results can be to accelerate the development of the artificial pancreatic design because of an administration of glucose through the oral according to the actual conditions then followed by administering insulin through infusion is following the actual conditions. In this study, the effects of insulin injection and physical activity on the glucose concentration level of type 1 diabetes mellitus (T1DM) will be simulated. A modified oral minimal model using the effects of physical activity and external insulin treatment was developed in the present study. Based on this simulation study, the main objective of this study was to vary insulin injections while carrying out physical activities that could validate the effects of decreased blood glucose levels in T1DM patients. These simulation results showed that the greater the injection of insulin during physical activity, the faster the rate of blood glucose concentration decreases. The optimum experiment simulation has been obtained to represent a treatment accurately by comparing the experimental data of a normal glucose concentration.
Solution of d-dimension time independent cosmic string using supersymmetry quantum mechanics method for rosen morse, scarf II and scarf I non-central potentials
Authors: Suparmi A , Anggraini D , Cari C , Ma’arif M 
Published: July 2020

Abstract
Solution of d-dimension time independent cosmic string for rosen morse, scarf II and scarf I non-central potentials was solved using supersymmetry quantum mechanics method. Variable separation method was applied to the d-dimension time independent cosmic string equation, and then the d-dimension time independent cosmic string equation was reduced into d one dimensional schrodinger equation. Supersymmetry quantum mechanics method was used to analyze radial wave function, angular wave functions, and energy level. Energy levels were higher by the presence of rosen morse, scarf II and scarf I potentials parameters. The increased value of nr
, n

θ
2
and n

θ
4
caused the increase in energy levels, the decrease of cosmic string α parameter, caused the decrease of energy levels and the increasing of number n

θ
1
and n

θ
3
caused the decrease of energy levels.
STEM literacy load analysis on the planning and implementation of science learning on the topic of simple machine
Authors: Surani E , Jalmo T , Abdurrahman  
Published: July 2020

Abstract
The purpose of this study was to determine STEM literacy in the planning and implementation of science learning on the topic of simple machine. This research method is a descriptive qualitative method. Data were obtained using observations, document analysis, and interviews, which involved 200 junior high school science teachers in six districts of Lampung province, data analyzed with percentage. The results of STEM literacy analysis on the planning of natural science learning on the topic of simple machine have a high category of planning average (61%) and the average category of implementation is also of a high category (65%). Data analysis shows that learning science in simple machine material had integrated STEM but focused more on science and rarely used technology in student learning. Also, teachers realize that applying the STEM approach makes student learning more relevant, stimulates the emergence of meaningful experiences, encourages students to think higher and solve problems and increase retention. So that by the demands of the revolutionary education era 4.0.
The thickness effect to optical properties of SnO2 thin film with doping fluorine
Authors: Susilawati  , Doyan A , Muliyadi L , Hakim S , Taufik M 
Published: July 2020

Abstract
Synthesis of SnO2:F thin layer was grown using the sol-gel spin coating method on a glass substrate with various layers (one to four layers). The purpose of the synthesis was to determine the optical properties of thin layers including transmittance, absorbance, energy bandgap, and activation energy. The optical properties of the layers were characterized using UV-Vis spectrophotometers with a wavelength of 200-1100 nm. The results showed that at a wavelength of 300 nm the absorbance value decreased with an increasing number of layers. Absorbance values obtained for variations in layers (one to four layers) for the percentage of 95:5% and 75:25%, respectively 3.59-2.85 and 4.30-3.42, while the transmittance value decreased, namely 96.8-79.6% and 98.3-81.1%. Besides, the energy bandgap obtained decreases with an increasing number of layers. The energy bandgap decreased from 3.69-3.56 eV and 3.59-3.42 eV for direct allowed, while 4.00-3.91 eV and 3.96-3.83 eV for indirect allowed. Activation energy decreased from 0.23-0.07 eV and 4.35-1.43 eV.
Estimation of execution time for multi-stage control operations
Authors: Balakin A , Kopp V 
Published: July 2020

Abstract
The paper considers issues related to such a multiple measurements approach where the measurement results affect the number of measurements taken. This may result in a significant increase in the measurement time. The work takes into account the change in the probability that the product will be suitable after a specific measurement. These probabilities depend on the number of measurements. The given algorithm for controlling the measurement process shows the random nature of the duration of its execution, which in turn leads to the need to study the duration of multiple measurements. In this paper, a semi-Markov model is constructed that allows us to determine the functions of time distribution between events in the output flow formed after measurements. The resulting model makes it possible to connect it with models of elements of the highest levels of the hierarchy of the production structure. After a specified maximum number of measurements, the model assumes that a part of the measured product is defective and thus shall be rejected. The constructed semi-Markov model may be used to predict the performance of a technical system that uses multiple measurements to improve accuracy.
Hydromechanical method of control of drillstring torsional vibrations
Authors: Bashmur K A , Petrovsky E A , Smirnov N A , Tynchenko V S , Bukhtoyarov V V , Kukartsev V V , Kurashkin S O 
Published: July 2020

Abstract
The article discusses issues related to the vibrations of drillstring (DS). The relevance of the fight against torsional fluctuations DS and the reasons for their occurrence are analyzed. The hydromechanical method of control of torsional oscillations DS and device for its implementation is proposed. This method is characterized by its versatility and practically does not depend on the conditions of well drilling. Characteristics of the developed control method are determined by means of the hydraulic model of drilling mud behavior. The model illustrates the operability of the method and can assist in the selection of parameters for regulator design.
Technological potential of impact vibration damper of drill string with discrete working medium
Authors: Zagulyaev A V , Bashmur K A , Petrovsky E A , Tynchenko V S , Smirnov N A , Kukartsev V V , Kurashkin S O 
Published: July 2020

Abstract
The article discusses issues related to vibrations of drilling string bottom layout during construction of oil and gas wells. Analysis of causes of longitudinal vibrations occurring during rotary drilling is carried out. Invention proposes using vibration dampers of impact principle of action using discrete working medium. We described a device of this type of vibration dampers for drill columns. A probabilistic model of shock vibration damper operation with discrete operating medium is given. Analysis of the model shows the efficiency of using these types of vibration dampers to eliminate high-amplitude vibrations of drill columns.
Methodological and technological aspects of creation of digital platforms in ideology of open information systems
Authors: Boichenko A V , Lukinova O V 
Published: July 2020

Abstract
In the article it is shown that the process of digitalization of the information society, which is now a trend of world development, should be considered in the context of consumer, management and technological aspects. The conceptual model of interrelation of concepts of digital economy, which are associated with objects of digitalization, is described: digital transformation, cloud computing, information infrastructure, the digital platform, the integrated digital platform, platform economy, an ecosystem. These concepts are interpreted from the point of view of service-oriented architectures; properties of public service are described. Methodological and technological aspects of digital economy platforms design are considered in terms of open systems model, for which the main definitions and properties are given. The example of the OSE/RM open systems model shows the specifics of digital platforms related to their reorientation towards application industries. It is stressed that a feature of digital platforms is the fact that the platform becomes a provider of application platform services to external consumers. The tasks that the digital platform should solve in a new capacity are formulated.
On the location of a power line fault
Authors: Buryanina N S , Korolyuk Y F , Koryakina M L , Lesnykh E V , Suslov K V 
Published: July 2020

Abstract
The paper proposes an algorithm to exclude the aperiodic components from short circuit currents. The computer-implemented algorithm allows locating a fault and a phase failure in 0.5 - 0.6 milliseconds. During this time interval, the magnetic cores of current transformers (CTs) do not reach saturation and processors receive undistorted information from the current transformers. Four measurements of instantaneous values of currents that are made in equal time intervals (sampling intervals) are sufficient to implement the algorithm. The exclusion of aperiodic components increases the accuracy of the fault location. The algorithm can also be used in the location of open-phase fault and in the digital relay protection based on the measurement of current and voltage.
Analysis of the life cycle of a library information resource using Process Mining technology
Authors: Dorrer M G , Popov A A , Bartuzanova A N 
Published: July 2020

Abstract
The purpose of this work is to evaluate the applicability of the Process Mining methodology for the analysis of life cycle models of information resources. ProM software was used with the Inductive visual miner plugin. The source data was a database of the Seattle Public library hosted on the site Kaggle.com. Even from a fragment of the transaction history of library information resources, it was possible to recover the lifecycle model. The result confirms that it is possible to build and analyze models of the life cycle of information resources based on the event history logs.
Influence of the oxide phase on the process of inflation of composition from highly dispersed porous iron
Authors: Alibekov S Ya , Dovydenkov V A , Zvereva O S , Egorov A V , Pavlov A I , Lysyannikov A V , Kaizer Yu F , Demchenko A I 
Published: July 2020

Abstract
The article describes a new technology for the production of steel parts for structural purposes. The technology is based on molding mixtures of iron powders, iron oxide powders and a binder. Technological processes include the processes of vacuum reduction of iron oxide and a binder material with subsequent sintering of the mixture. The study of the features of the brass infiltration process is carried out on highly porous iron-based blanks with pore sizes less than 1 μm with various percentages of the starting components. The analysis of the structures and mechanical properties of materials obtained on the basis of the developed technology has been performed. The mechanism of infiltration of highly iron-based preforms based on iron obtained by casting from the compositions “iron-iron oxide-phenol-formaldehyde resin” obtained in three stages is established. Recommendations have been developed for the pilot production of products of complex shape from iron-based metal powders, including of casting molding operations, oxide reduction and sintering operations, followed by brass infiltration and heat treatment of the products. The introduction of new technology makes it possible to produce products of complex shapes with a high level of mechanical properties, improved dimensional accuracy and lower cost.
Identification of the parallel 3-PRRR manipulator parameters considering the workspace boundaries and the passive orthosis movements
Authors: Malyshev D I , Nozdracheva A V , Kholoshevskaya L R 
Published: July 2020

Abstract
The article discusses a system of rehabilitation of the lower extremities based on a passive orthosis in the form of a sequential RRRR mechanism and an active parallel 3-PRRR robot. Effective numerical methods and algorithms were developed and tested that made it possible to determine the minimum geometric parameters of the active parallel mechanism that ensure the movement of a passive orthosis within the working area in accordance with clinical data when simulating walking. The simulation results are presented by visualizing the exported workspaces in the STL format.
Reduced energy consumption when feeding raw materials to the reactor for the production of carbon black
Authors: Mukhamadeev E Z 
Published: July 2020

Abstract
This article describes possible ways to reduce the energy consumption of pumps that supply liquid hydrocarbon feed to the nozzles of reactors for the production of carbon black. For achieving this goal, it is proposed to separate the functions performed by the pumps. Some pumps provide circulation, heating, dehydration of raw materials, and supply them to the reactor compartment. Other pumps increase the pressure of the liquid directly in front of the nozzles of the reactors. It is advisable to use piston pumps with pulsation smoothing pumps to increase the pressure.
Analogies method application to increase the involvement degree in the deposits development of the Jurassic oil and gas complex in Western Siberia
Authors: Mukhametshin V V , Kuleshova L S 
Published: July 2020

Abstract
About 250 objects of the Jurassic and Paleozoic ages of four oil and gas regions of the West Siberian oil and gas province under development were identified and grouped. Eight groups of objects were identified based on the use of data on tectonic-stratigraphic confinement and data on the bedding conditions, geological, physical, and physicochemical properties of the strata and the fluids saturating them. The dominant influence of tectonic-stratigraphic confinement of objects in the formation of the features of the geological structure of deposits and their filtration-capacitive properties is established. The selected groups of objects are ranked according to the degree of similarity and difference in the multidimensional space of parameters that have a collective effect on the process of reserves development. Clusters are presented that make it possible to use the accumulated experience of developing deposits of the Jurassic and Paleozoic ages not only within the considered oil and gas regions but also regions adjacent to them. The results obtained made it possible to create a methodological base for searching not only objects but also groups of similar objects for deposits leaving exploration to engage in active development and increase the degree of oil reserves development in the Jurassic oil and gas complex deposits.
Instrumental monitoring of the load of the automotive alternator during the movement of the vehicle
Authors: Puzakov A V 
Published: July 2020

Abstract
The charge balance of the vehicle indicates whether the starter battery is being charged while the vehicle is running. For normal operation of the power supply system, the charge balance must remain positive, preventing progressive discharge of the battery. A decisive influence on the balance of electricity is provided by the current output of the alternator, which depends on the rotor speed. The maximum current output of the alternator is described by a current-speed characteristic depending on the technical condition of the alternator. In the process of vehicle movement, the rotor speed and alternator current strength vary over a wide range determined experimentally. The ratio of these parameters is the alternator efficiency coefficient, which can be used to assess the technical condition of the automotive alternator. The productivity of the vehicle’s charge balance is objectively evaluated by the alternator load factor. Further research will be aimed at identifying changes in the charge balance of the vehicle in the event of a malfunction of the automotive alternator and starter battery.
Formation of shot dimples during shot peening
Authors: Koltsov V P , Vinh Le Tri , Rakitskaya V B , Tardybaeva E V 
Published: July 2020

Abstract
In the aircraft industry, the technology of shot peen treatment is successfully used for the manufacture of long panels and sheaths, both for forming and finishing hardening. Shot dimples increase the roughness of the treated surface, so after the shot peening, the surface should be grinded with flap wheels to improve the roughness values by partially removing the traces of shot impact. To assess the quality of shot peening as a monitoring indicator, in practice the degree of coverage of shot dimples on the treated surface is used, which is determined by the percentages of the total area of shot dimples to the total area of the considered treatment part. To assign the modes of subsequent grinding with flap wheels, it is necessary to determine the allowance for grinding, which is determined by the value of the maximum depth of the largest dimple within the base area of the treated surface. The paper presents a method of creating a mathematical model to determine the size of dimples in shot peening, as well as modeling and engineering analysis of the shot peening process with the finite element method.