bluuebunny/crossref_metadata_2025 huggingface dataset:
Cancer cell CCR2 orchestrates suppression of the adaptive immune response
Authors: Fein Miriam R. , He Xue-Yan , Almeida Ana S. , Bružas Emilis , Pommier Arnaud , Yan Ran , Eberhardt Anaïs , Fearon Douglas T. , Van Aelst Linda , Wilkinson John Erby , dos Santos Camila O. , Egeblad Mikala
Published: July 2020

C-C chemokine receptor type 2 (CCR2) is expressed on monocytes and facilitates their recruitment to tumors. Though breast cancer cells also express CCR2, its functions in these cells are unclear. We found that Ccr2 deletion in cancer cells led to reduced tumor growth and approximately twofold longer survival in an orthotopic, isograft breast cancer mouse model. Deletion of Ccr2 in cancer cells resulted in multiple alterations associated with better immune control: increased infiltration and activation of cytotoxic T lymphocytes (CTLs) and CD103+ cross-presenting dendritic cells (DCs), as well as up-regulation of MHC class I and down-regulation of checkpoint regulator PD-L1 on the cancer cells. Pharmacological or genetic targeting of CCR2 increased cancer cell sensitivity to CTLs and enabled the cancer cells to induce DC maturation toward the CD103+ subtype. Consistently, Ccr2−/− cancer cells did not induce immune suppression in Batf3−/− mice lacking CD103+ DCs. Our results establish that CCR2 signaling in cancer cells can orchestrate suppression of the immune response.
Cholesterol helps PIEZO1 use the force
Authors: Short Ben
Published: July 2020

JGP study shows that disruption of membrane cholesterol alters the organization and activity of mechanosensitive PIEZO1 channels.
Deep learning for certification of the quality of the data acquired by the CMS Experiment
Authors: Alan Pol Adrian , Azzolini Virginia , Cerminara Gianluca , De Guio Federico , Franzoni Giovanni , Germain Cecile , Pierini Maurizio , Krzyżek Tomasz
Published: July 2020

Certifying the data recorded by the Compact Muon Solenoid (CMS) experiment at CERN is a crucial and demanding task as the data is used for publication of physics results. Anomalies caused by detector malfunctioning or sub-optimal data processing are difficult to enumerate a priori and occur rarely, making it difficult to use classical supervised classification. We base out prototype towards the automation of such procedure on a semi-supervised approach using deep autoencoders. We demonstrate the ability of the model to detect anomalies with high accuracy, when compared against the outcome of the fully supervised methods. We show that the model has great interpretability of the results, ascribing the origin of the problems in the data to a specific sub-detector or physics object. Finally, we address the issue of feature dependency on the LHC beam intensity.
Constructing mass-decorrelated hadronic decay taggers in ATLAS
Authors: Søgaard Andreas
Published: July 2020

A large number of physics processes as seen by the ATLAS experiment manifest as collimated, hadronic sprays of particles known as ‘jets.’ Jets originating from the hadronic decay of massive particles are commonly used in searches for new physics. ATLAS has employed multivariate discriminants for the challenging task of identifying the origin of a given jet. However, such classifiers exhibit strong non-linear correlations with the invariant mass of the jet, complicating analyses which make use of the mass spectrum. A comprehensive study of different mass-decorrelation techniques is performed with ATLAS simulated datasets, comparing designed decorrelated taggers (DDT), fixed-efficiency k-NN regression, convolved substructure (CSS), adversarial neural networks (ANNs), and adaptive boosting for uniform efficiency (uBoost). Performance is evaluated using suitable metrics for classification and mass-decorrelation.
Analysis of physical properties and mechanics of rocks in the karst region of Pangkep Regency
Authors: Arsyad M , Tiwow V A , Sulistiawaty  , Sahdian I A
Published: July 2020

Panaikang, Biraeng Village, Minasate’ne District is one of the villages in the Pangkep karst area which has a topographical morphology with many cracks, fissures, and cavities on the surface. The formation of karst from the process of dissolving water against carbonate rocks. Analysis of physical and mechanical properties is important to know. This study aims to determine the value of porosity, density and rock compressive strength values in the karst region of the Pangkep Regency. The testing of physical and mechanical properties was carried out to obtain rock conditions and quality using engineering methods. The number of samples used 10 rock samples with a minimum distance of each sample ± 10 meters using a random method. The results obtained by the rock type at the site are dolomite limestone with a porosity range value of 0–5% and a modified limestone with a porosity range value of 5–50%. Rock density is in the range of values 2.2-2.7 gr/cm3. Rock compressive strength testing shows that the rock in the area has weak strength quality with a range of values of 5-25 MPa and medium strength quality with a value range of 25-50 MPa.
Claim and warrant: a contextual physics learning strategy to enhance studens’ argumentation skills
Authors: Viyanti  , Cari  , Sunarno W , Prasetyo Z K , Maulina H
Published: July 2020

Students’ argumentation skills both in the learning process and assessment to realize the transformation of the production of quality claim and warrant are very important to be implemented. This study is trying to analyze the process of students’ argumentation skills transformation through a contextual physics learning strategy called “Claim and Warrant”. This study used descriptive survey method with eleven grade student in Bandar Lampung as the population. Beside that, cluster random sampling technique was used to specify the sample. A complex problems as an exercise were given to thirty two senior high school students in order to produce alternative statements and the basis of theoretical-evidence relations. The data were obtained through reasoned multiple choice tests with feedback andanalyzed through a feedback-assessment process. The results showed the increasing of students’ argumentation skills in form of production of alternative statements and counter.
Effectiveness of physics electronic modules based on Self Directed Learning Model (SDL) towards the understanding of dynamic fluid concept
Authors: Diansah I , Asyhari A
Published: July 2020

This study aims to determine the effectiveness of electronic modules based on the self-directed learning (SDL) model in helping students of Al-Azhar 3 High School Bandar Lampung to understand the concept of dynamic fluid. The research conducted is poor experiment research, with static group comparison design. Two samples, the experimental class, and the control class were selected in this study with purposive sampling techniques. Hypothesis testing uses Mann Whitney Hypothesis Test and Effect size test with the help of SPSS tools. The hypothesis test results show that the sig value is 0.00. The sig value ≤0.05 and the effect size test result is 1.736895962, where d> 0.8, so the effectiveness of the electronic module is high. So the hypothesis is accepted, or the use of electronic physics modules based on the self-directed learning model is effective in helping students of Al-Azhar High School 3 Bandarlampung to understand the concept of dynamic fluid. So this electronic physics module is proven to be able to answer students’ needs for learning resources that make it easy for students to understand the concept of dynamic fluids that are following the demands of the times and learning needs in the 2013 curriculum.
Effects of magnetic fields on the Current-Voltage (I-V) characteristics of the chitosan membrane
Authors: Rupiasih N N , Sumadiyasa M , Putra I K , Wulandari R , Sari I W
Published: July 2020

This work aimed to study the effect of magnetic fields on the current-voltage (I-V) characteristics of a chitosan membrane. The study consists of the plateau length, limiting current density (LCD), and the ratio of resistance of region III (RIII) and region I (RI) (RIII/RI). The chitosan membranes were prepared by a casting method using chitosan as a matrix and acetic acid as a solvent. The chitosan membranes polymerized under a strong magnetic field of 1.5 mT applied along the membrane surface with various times i.e. 2, 4, 8, and 12 h. The I-V measurements were conducted using a cell model with two working electrodes made of platinum and two reference electrodes connected to a voltmeter. The electrolyte solutions used were HCl and CaCl2 with a concentration of 0.025 M. All experiments were carried out at a room temperature of 28.6 °C. The results showed that the plateau length, LCD and RIII/RI of the chitosan membrane is influenced by the magnetic field given during the membrane formation reaction. The magnitude of the impact depends on the length of exposure. These results can be used in tailoring the chitosan membrane according to the application needed.
Environment management in prospect coal mining area at Handil Kutai Kartanegara, East Kalimantan using resistivity tomography, wenner configuration
Authors: Parwatiningtyas D , Putro B W A
Published: July 2020

The geoscanning method is a geophysical method that utilizes the nature of resistivity type to study the subsurface conditions of the earth. Resistivity resistance is an important parameter to characterize the subsurface physical state, which is associated with material and subsurface conditions.[1]. Based on an analysis of the distribution of this type of prisoner, furthermore we can be interpretation the conditions of under the earth’s surface. The purpose of this investigation is to obtain information below the surface of the earth and coal targets contained in there using the Geoscanning method with Wenner configuration. Based on the results of 3 trajectory inversion of location of 1 resistivity tomography data, the best coal prospect area on line1, line 2, location of 1 (Pit 10) with alluvium and hard material types. Only constraints on line 1, the coal prospects are covered by analysis of weak zones to the east, in the form of swamp soft soil with ground water classification - clay which is characterized by light blue - dark blue with resistivity values 10 - 34.7 ohms/metres to a depth of 30 metres. Whereas on line 2 which is adjacent to vico 1 and silk wells, the condition of the coal land was safe for exploration activities to a depth of 40 metres, without disturbing the oil well area, and far from the silk location, and the condition of the soil material is solid and no weak zone analysis is found. In the Pit 5 area on line 4, the prospect of coal mining is covered by a landslide-prone zone, where the mine location area (pit 5) is dominated by soft soil classification of sandstone material (resistivity 8.6 -49.2 ohms/metres), blue - gray - light green along the long stretch of North - South direction along 240 metres with a depth reaching 24 metres. This area has the prospect of coal having a moderate resistivity (including small for the quality of coal), namely the range 76 - 182 ohms/metres, marked by red - orange - yellow, with a target depth of up to 39.4 metres.
Estimation radiation dose from operation of petroleum NORM waste disposal in landfill using TSD-DOSE
Authors: Dwipayana C A W , Moersidik S S , Pratama M A
Published: July 2020

In the petroleum industry, Naturally Occurring Radioactive Materials (NORM) are often enhanced as a result of industrial operation. Radiation protection must be applied in every step of NORM management including disposal. Top rank choice for NORM disposal is landfill. Landfill must provide sufficient protection to both human health and the environment, not only for future but also for operational phase. Landfill workers, including receiving worker, driver and placement worker, are evaluated to estimate potential exposures resulting from landfill operation. Estimation is done for radioisotopes which are of concern in the oil and gas industry, Ra-226, Ra-228, Th-232 and Pb-210. The TSD-DOSE computer code, developed by Argonne National Laboratory, is use to estimate radiological doses to workers from operations at a treatment, storage, and disposal (TSD) facility. The characteristics of the time needed by workers were obtained from observations and discussions with workers at PPLI Cileungsi Hazardous Landfill. Disposal of NORM Waste in bulk form give higher dose than containerized waste. For receiving worker, Ra-226 gives higher dose and for placement worker higher dose arise from Th-232. The size of the vehicle used to transport NORM waste affects the radiation dose received by landfill workers.
Gravitational wave echoes from quark stars
Authors: Kartini D , Sulaksono A
Published: July 2020

It has recently been reported that gravitational wave echoes at a frequency of about 72 Hz have been detected with the significance of 4.2σ from two neutron star merger event GW170817. Alternatively, the echoes of a gravitational wave can be obtained from ultra-compact stars, i.e., stars with compactness between 1/3 and 4/9. The mass-radius relation of ultra-compact stars is crossing the photon sphere line, where the line obeys the relation compactness equal to 1/3. Furthermore, it has recently been reported that strange stars within a simplest MIT-Bag model with an ultra-stiff equation of state (EoS) where the speed of sound equal to speed of light in vacuum can produce gravitational wave echoes with frequencies on the order of tens of kilohertz. For more realistic models of strange star equation of state, the speed of sound in the matter is physically less than one, and it should be density-dependent. In this report, we will check whether the more realistic EoS of quark stars can emit gravitational wave echoes or not. Here we employ two models of EoSs such as MIT-Bag models with speed of sound =1/√3 and CIDDM models with the density-dependent speed of sound.
ICT learning media comparative studies: simulation, e-modules, videos
Authors: Suyatna A
Published: July 2020

This study was aimed to determine an effective model of ICT learning media: simulation, e-modules, video to improve science learning outcomes of cognitive domains and science process skills (SPS). We used a quasi-experiment with pretest-posttest group design. This study examined the comparison of three ICT-based media implementation in “Unit and Measurement” learning. The media used were simulations, e-modules, and video. The sample involved three classes of seventh graders in Bandar Lampung which were taken purposively. Each class was treated by using simulations, e-modules, and videos. Data were collected by using test and observation techniques. Data was analyzed by using paired sample t-test, one-way ANOVA, and multiple comparisons. The results indicated that the use of ICT media simulation, e-modules, and videos that were guided by the worksheet could significantly improve the learning outcomes in the cognitive domains of junior high school students at the level of trust 95%. There was a significant difference in the average learning outcomes on cognitive domains and SPS among learning aided by interactive simulation, e-modules, and videos. The learning outcomes which the class was assisted by the e-module ICT media model show the highest result.
Is there a correlation between rainfall and soil moisture on peatlands in South Sumatra?
Authors: Irfan M , Setya O C , Virgo F , Sutopo  , Ariani M , Sulaiman A , Iskandar I
Published: July 2020

Data of this study was obtained from direct measurement using an integrated observation system namely
SE
nsory data transmission
S
ervice
A
ssisted by
M
idori
E
ngineering laboratory (SESAME). The SESAME directly measures and records groundwater levels, soil moisture, skin temperature, and rainfall in peatland areas. There are two SESAME stations was used in this study, that are located in the Peatland Hydrological Unit (PHU) Lumpur River 1 and PHU Lumpur River 2. This study aims to find a correlation between Rainfall and Soil Moisture on peatlands in South Sumatra represented by the two PHUs. The results of statistical analysis show that rainfall has a significant linear correlation with soil moisture. The correlation coefficients obtained at PHU Lumpur River I and PHU Lumpur River II were 0.78, 0.64 respectively. Furthermore, the result of the empirical equation can be used to obtain the value of soil moisture based on the value of rainfall at this research location if one day soil moisture sensors are damaged.
Leadership in green school practices: a case study of the principal’s roles towards reducing global warming risk in Lampung, Indonesia
Authors: Pebriantika R , Abdurrahman A , Hariri H , Sowiyah  , Rahman B
Published: July 2020

The implementation of green schools is a starting point for developing environmental awareness and responsibility, begin with educating students in a healthy and sustainable environment. In this perspective, principal leadership will contribute to embody green school with increasing the pro‐environmental attitudes, clean and healthy living behaviour, and habits of individuals, whether at home, or in school. The main aim of this study is to review research evidence and a conceptual framework of the school leadership that contribute to build sustainability school. The design of this study is qualitative approach with case study method in Lampung Province, Indonesia, specifically in the North Lampung District. This study presents results from interviews, observation, and documentation analysis. We sought to understand how role model and school culture provide education service with a particular interest in the physical built environment of this unique school. We found, however, these factors supported school’s ability to develop and maintain green school and linked to the principal’s actions as school leader. These factors are important for school improvement, especially for schools in disaster-risk areas, communities are increasingly asked to improve students’ awareness to environment.
Measuring protein surface density on glass substrate using fluorescence fluctuation spectroscopy
Authors: Wahyuni D , Balland M , Destaing O , Wang I , Delon A
Published: July 2020

Surface functionalization implies to know the surface density of proteins, which, for cellular biology, impacts on cells behavior (motility, spreading, and fate). Contradictory, the quantification of this parameter is lacking. We studied the surface density of deposited proteins on glass using the Image Correlation Spectroscopy (ICS) technique as part of the Fluorescence Fluctuation Microscopy (FFM) methods. As the confocal microscope scans the surface, the proteins deposited on it contribute to the image through the confocal point spread function (PSF). The width of the image autocorrelation is equal to the width of the PSF; its amplitude provides the average number of proteins within the PSF, proportional to the surface density. Nevertheless, the assessment of the surface density can be underestimated if the surface coverage is not uniform or overestimated if a background contributes to the fluorescence signal. Hence, we combine the ICS and photobleaching (pICS) to detect these artifacts and estimate the actual surface density. The pICS method makes it possible to have a better control of the estimation of the surface density. We noticed that the surface density of proteins increased with their initial concentration in solutions. Overall, FFM is a quantitative technique to infer the surface density of protein.
Misconception of weights, normal forces and Newton third law
Authors: Mongan S W , Mondolang A H , Poluakan C
Published: July 2020

Research has been conducted relating to the concept of forces in physics learning. The purpose of this study is to identify student’s misconception and difficulties in determining the weight and normal from tail of vector, the weight and the normal direction of vector and Newton third law. The study was conducted in two groups of students. The first group was microteaching class and the second group was students who had studied mechanics. The research method is carried out with two approaches namely qualitative and quantitative. The quantitative method is done by using a test instrument given to participants through the pre-test and post-test stages. While the qualitative method of conducting interviews with participants after the post-test session. The results of the study showed that 55% of students were unable to determine the exact gravity capture point, and 93% of students were unable to describe the exact position of the normal force, and 95% of students answered incorrectly about the concept of action forces similar to the reaction forces. From the interviews, it was revealed that students were still confused by the representation of the vector of force representations and not sure about the drawing vector they made. Physics will be well understood if style concept learning is given on the basis of the philosophy of science correctly. Research recommendations are very important that students understand the concept of forces correctly which is based on the application of appropriate vector concepts.
Perspective of students’ science communication in science learning: opportunity in developing makerspace STEM learning approach
Authors: Miranti H , Abdurrahman  , Hasnunidah N
Published: July 2020

The demands of the 21st century encourage education in Indonesia so that it is expected to create quality human beings who are able to compete in the global competition in the 21st century by having skills, one of them is science communication skills. This study aimed to describe and analyze the perceptions of students’ science communication which is applied with learning that integrated with Science, Technology, Engineering, and Mathematics (STEM) approach. The study was conducted at junior high schools in Bandar Lampung involving 100 students. The method used in this study was a mixed method with Sequential Explanatory Design. The research instrument used a questionnaire containing 10 oral communication statements and 10 written communication statements that were used to analyze students’ scientific communication profiles. The results showed that science oral communication was good (63.75%), but low (36.25%) in writing. In addition, learning with STEM approach in this context through practicum and project is preferred by students compared to discussion or traditional learning.
Simulation approach of chamber purging experiment by nitrogen gas
Authors: Marjunus R
Published: July 2020

Chamber purging is usually required in a gas sensing research, in order to make a perfect dry air condition (Relative Humidity/RH = 0%) in the chamber. An experiment shows that RH of the cylindrical chamber (volume = 7.5 cm3) never touch 0% (only 32% and 4%) although it was purged by 100 and 300 sccm of synthetic air (consists of 20% O2 and 80% of N2). It was also obtained the same condition when N2 gas was used instead of synthetic air. In order to understand this experiment’s results, a simulation has been done. The simulation approach using a box-form chamber (volume = 9.6 cm3) shows that the combination of the diffusion-convection process of N2 gas is responsible for the results of the chamber purging experiment instead of pure diffusion or pure convection. For the future step, it is needed further investigation (experiment and simulation) in order to reach 0% RH.
Teacher expectation towards interactive multimedia integrated with STEM in learning physics: Preliminary study on geometry optic learning material
Authors: Pricilia A , Abdurrahman A , Herlina K
Published: July 2020

Recently, the challenge of industrial revolution 4.0 has become a discourse in education. Education is a way for a country to face the development of modern science and technology. So, in this time, education requires systematic preparation in making interactive teaching materials as one of the important components in the learning process. This study aims to describe and analyze the perceptions of teachers and students about interactive teaching materials integrated STEM in physics learning. The study was conducted in high school in Bandar Lampung in class XI involving 133 students and 12 physics teachers. The method used is mixed method. The research instruments used were questionnaires and interviews. The results of the study show that the teacher has not fully used teaching materials with interactive multimedia, and the teaching materials used have not been integrated with Science, Technology, Engineering, and Mathematics (STEM), the kind of teaching material that is needed by students and teachers is teaching material that is interactive and integrated with STEM. STEM make it possible to students to explore their ability in Science, Technology, Engineering, and Mathematics. So, it is necessary to develop interactive teaching material integrated with STEM to face the challenges of the Industrial Revolution 4.0 and fulfill competency standards in the 21st Century. The lesson needed for developing interactive teaching materials is geometry optic.
The causalitic learning model to increase students’ problem-solving ability
Authors: Rokhmat J , Marzuki  , Kosim  , Verawati N N S
Published: July 2020

This research aimed to describe the causalitic-learning-model and its’ implementation to increase the Problem-solving Ability (PSA) (causalitic = causality-and-analytic). This research used mixed method of embedded experimental two phases. The model has been implemented at three universities and seven senior high schools (SHS) in Mataram-Lombok-Indonesia in physics on seven undergraduate-subjects (kinematics, Newton’s law of motion, work and energy, impule and momentum, gravity, rigid equilibrium, thermodynamics) and six SHS-subjects (fluid, optical geometry, impulse and momentum, heat, rigid equilibrium, and direct electrical-current). The instruments consisted of pre-learning-task, learner-worksheet, PSA’s problems, and questionnaire. The score of PSA of pre-service-teachers were analyzed with t-test of sign ranks by Wilcoxon but the PSA of SHS-students were analyzed with t-tests, while the responses of questionnaire were analyzed descriptively. The results show that the model is effective to increase the PSA (with significance-level 5%); for pre-service-teachers, the normalized-gain average 0.15-0.53 for low-group and 0.29–0.77 for high-group, while for the SHS’ students, the normalized-gains is 0.20-0.83 and all students give positive responses. The phases of the learning-model include orientation, exploration and causality-development, argument-preparation, and evaluation. This learning-model is very useful as a reference when constructing learning using this model at any discipline and any level of education.
The effect of blended learning setting on students’ critical thinking skills in physics
Authors: Suana W , Ningsih W S A , Maharta N , Putri N M A A
Published: July 2020

This paper reports a study and results of the improvement of critical thinking skills in a blended learning environment in teaching high school physics. The research was a mixed-method quasi-experimental followed by a qualitative survey. Schoology is chosen as a blended platform for this study. The data of students’ critical thinking skills were obtained by multiple choice tests and were analyzed by using n-gain. Moreover, the information on students’ responses to the blended learning model was collected by open-ended questions at the end of learning process. Based on the results of the study, there were significant effects of blended learning on critical thinking skills. It is also reported that students have high interest, ease of learning, and have benefits in increasing their knowledge. It suggests that Schoology-based blended learning model is effective to improve students’ critical thinking in Physics learning process.
The enhanced of photoresponse of ZnO nanorods film-coated by Cu2O
Authors: Maryam S , Dewi A S P , Mufti N , Muyasaroh A F , Taufiq A , Hidayat A , Sunaryono
Published: July 2020

Light detectors are widely used in generating energy from sunlight, medicine, space communications, ozone layer monitoring and missile warning systems, and others. The active materials that potential used as a detector of visible light and UV is ZnO. However, ZnO has a high bandgap of 3.04 eV so it is not suitable for absorbing light at short wavelengths. Cuprous oxide (Cu2O) is a p-type of semiconductor with a small band, therefore it can increase the wavelength absorption range. The aim of this study is to improve the light response of ZnO nanorods by coating Cu2O. The samples were characterized by X-ray Diffractometer (XRD), Scanning Electron Microscopy (SEM), UV-Vis Spectrometry, FTIR, and photoresponse test. The results show coating Cu2O on ZnO nanorods succeeded in reducing the bandgap value, which is 2.47 eV. Reducing the band gap value is in accordance with the photoresponse test. The response of a sample that has a small bandgap is a fast response.
The influence of TiO2 film thickness in Dye-Sensitized Solar Cells (DSSC) performance based on TiO2/Ag@TiO2-ZnO
Authors: Rahman M F , Nasikhudin  , Hidayat A , Diantoro M
Published: July 2020

The effects of TiO2 film thickness in double layer TiO2/Ag@TiO2-ZnO as the photo-anode, on the performance of dye-sensitized solar cells have been investigated. Dye adsorption and band gap of the electrode are paramount importance to enhance the efficiency. With the increase of TiO2 film, thickness is expected to increase dye adsorption while silver (Ag) doping in semiconductor electrode is proposed to reduce the band gap. Experimentally, TiO2 nanoparticle was deposited on ITO glass by a spin coating method as a first layer with varying number of spin coating to obtain different of thickness. Ag@TiO2-ZnO was deposited above the first layer by the doctor blade method. The sample was characterized by using X-Ray Diffraction, SEM cross-sectional, UV-vis spectroscopy, and solar simulator. It is found that the increases TiO2 film thickness in double layer TiO2/Ag@TiO2-ZnO electrode increase the efficiency linearly. The optimum efficiency of 0.31747% was obtained in a double layer DSSC with TiO2 film thickness of 42.54 μm.
The prospective of STEM education: students’ perceptions about the role of interest growth in science literacy
Authors: Aini N , Jalmo T , Abdurrahman
Published: July 2020

This study aimed to describe students’ perception about the role of STEM in growth interest in scientific literacy. The study was conducted in Lampung province of Indonesia, involving 221 junior high school students and interview with 5science teachers. The method used in the research is a mixed method with Sequential Explanatory Design. Data were taken using Questioner, interview and Observation, Data were analyzed using descriptive analysis. The survey results show that students have a positive perception of the STEM approach. The results of the analysis of the STEM Approach most teachers have not utilized the STEM approach to provide an understanding of science. STEM approach not only provides an understanding of student science but also mathematical skills and conceptual understanding in science so STEM learning can support 2013 curriculum learning.
The use of teaching semiotic vectors in the introduction to physics
Authors: Mondolang A H , Poluakan C , Mongan S W
Published: July 2020

The purpose of this study was to produce a semiotic representation-based test instrument with a multiple-choice (MMC) model that could identify vector errors in a valid and reliable manner. This research method uses the Research & Development Model (R & D) which consists of four main stages, define, design, develop and disseminate. This research was implemented to the students of 2nd semester on 2018/2019 Academic Year of physics education study program totaling 25 people. The results shown that through semiotic representation in the assessment instrument based on the multiple-choice model in a valid and reliable way, it could identify errors in understanding vector concepts (weight centers, position vectors, vector lines, and weight center coordinates) of students. From this study, the use of semiotic representations in physics assessment instruments is recommended in vector concept learning in basic physics lectures to identify errors in vector concepts to improve physics teaching.
Validation of audio-based solar system visual aid for special school students
Authors: Widiyatun F , Sumarni R A , Astuti I A D , Bhakti Y B , Okyranida I Y , Dasmo D
Published: July 2020

Making and testing of miniature solar systems intended for students has been carried out and specifically for special school students. The purpose of making this tool is to help the learning process in students with special needs for science materials, especially in the solar system. The solar system visual aid consists of sun with its planets, including from Mercury to Neptune. Planets were designed to move automatically. In addition, this visual aid was also made audio containing explanations for each planet and also the sun. Validation of tools is carried out by material and media experts. The results of the material validation are good. While the media validation is sufficient and received well. This audio-based solar system visual aid is good enough to be used by special school students.
Artificial immune system as a high parallel intelligent information processing and protection system
Authors: Alchinov A I , Volkova E V , Daudov I M
Published: July 2020

The article discusses the possibilities of applying the artificial immune system to ensure the protection of information. It is described that, according to studies, processing of the immune system of external signals is carried out using a highly parallel process.
Forecasting for application of formation stimulation to BV6 formations of Las Eganskoye oil field
Authors: Andreev V E , Chizhov A P , Chibisov A V , Mukhametshin V Sh , Gazizov R R
Published: July 2020

Studies described in this paper were aimed at solving a set of problems related to selection, technological justification and design of enhanced oil recovery. Theoretical and laboratory studies of remaining reserves production were conducted, as well as prediction of their efficiency if applied to formation of Las Eganskoye oilfield.
Radioactive content in the investigated granites by geochemical analyses and radiophysical methods around Um Taghir, Central Eastern Desert, Egypt
Authors: Awad H A , Zakaly H M H , Nastavkin A V , El-Taher A
Published: July 2020

Um Taghir area is restricted along a shear zone of the Qena-Safaga road, actually it belongs to the Central Eastern Desert that represents one of the most important occurrences of radioactive elements in Egypt. The current study aims to calculate the content of the radioactive elements of the investigated granitic rocks by radiative methods for the geochemical analyses, are determined by (X-ray fluorescence (XRF) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The average concentrations values of 226Ra, 232 Th are lower than that of world’s average and the average activities in Egyptian soil. While in 40K series is higher than that of world’s average and the average activities in Egyptian soil. The range of measured activities differed widely as their presence in rocks samples depends on their physical, chemical and geo-chemical properties and the pertinent environment.
The physical basis of the vibration of the upper part of the pipe string when drilling wells
Authors: Bashmur K A , Petrovsky E A , Zharnakova M S , Bukhtoyarov V V , Kukartsev V V , Tynchenko V S , Petrenko V E
Published: July 2020

The article discusses the fundamental issues related to the assessment of the dynamics of the top drive system as one of the sources of vibration when drilling wells. The operational parameters of the drive load at which a resonance phenomenon is observed are determined. The optimal parameters for reducing the amplitudes of forced oscillations, their resonance phenomena are revealed. Methods of protecting the derrick and equipment for protecting unbalanced masses of the top drive from vibration are considered. The prospect of using the layout of the columns, including alloy pipes, is to protect the bit.
Enhancing metal processing efficiency based on using a lubricating-cooling agent with ultradispersed diamond powder
Authors: Petrovsky E A , Bashmur K A , Smirnov N A , Gorodov A A , Bukhtoyarov V V , Kukartsev V V , Tynchenko V S , Petrenko V E
Published: July 2020

The present study describes a new technological environment based on ultradispersed diamond graphite powder. The task is to further study effects of lubricating and cooling agent containing diamond nanopowder. The agent is fed into the zone of refinement or polishing of the part while affecting wear and durability of carbide tooling. The impact of the agent on the quality of the surface layer in the processing of heat-resistant steels and alloys is investigated. It also identifies the optimal agent composition when polishing a particular material. Experimental studies established a positive effect of the agent on the treated surface quality and other parameters of clean finishing and polishing of various metals.
Study of the impact of the lubricant-cooling agent with the diamond graphite submicropowder additive on the durability of AISI M2 steel drill bits
Authors: Petrovsky E A , Bashmur K A , Smirnov N A , Tynchenko V S , Bukhtoyarov V V , Gorodov A A , Petrenko V E , Kukartsev V V
Published: July 2020

The present study analyzes the impact of various lubricant-cooling process agents on the durability of drill bits made of AISI M2 (DIN 1.3343) high-speed steel. The research was conducted for a wide range of steels and alloys, namely: 1045, 321H, Mo-PM (molybdenum powder alloy), and W-Ni pseudo-alloy. New lubricant-cooling process agents with diamond graphite submicropowder additive are studied. The optimal composition of diamond graphite additive is revealed when drilling these steels and alloys. Experimental studies established a positive effect of lubricant-cooling process agents with the diamond graphite submicropowder additive on the durability of the drill bits made of AISI M2 steel.
Influence of the charge materials on the quality of cast wheel rims made from AK7 alloy
Authors: Cherepanov A I , Kukartsev V A , Kukartsev V V , Dzhioeva N N , Bets Yu S , Makarchuk I Yu
Published: July 2020

The widespread use of aluminum and alloys based on it in mechanical engineering is determined by high values of specific strength, increased corrosion resistance, as well as the ability to damp vibrations and high energy absorption. These indicators are especially important in the production of cars, as these alloys can reduce product weight and, as a result, the amount of fuel consumed. Reduced weight of cars can reduce harmful emissions into the environment and reduce the pressure on the road surface. Currently, AK7 cast aluminum alloy is the standard alloy for making rims. To obtain an alloy with the necessary properties, it is necessary to take into account the quality of the used charge materials. First of all, this applies to foundry alloys, which are used for alloying and alloy modification. In the study, we studied AlSi10 pig foundry alloy and AlTi5B1 foundry alloy rod.
Processing calibration results for measuring transducers with an integrated sensor
Authors: Emets S V , Polischouk I N , Kudayarov V N
Published: July 2020

The proper production process control is possible only if there is an information-measuring system equipped with a large set of measuring transducers of physical quantities. Currently, measuring transducers with semiconductor sensors are widely used. Along with high sensitivity to the measured value and repeatability of parameters, these transducers are sensible to stray quantities, which leads to additional errors. One way to reduce the additional errors of measuring transducers with an integrated sensor is to apply algorithmic correction, which involves a multifactorial calibration experiment, the processing of the results of which allows obtaining the conversion function. Algorithmic correction solves the issue of linearizing the conversion function and minimizes the effect of influencing factors on the measurement results. The conversion function quality and, consequently, the accuracy of further measurements largely depend on the correctness of the calibration experiment results. Random outliers (spurious errors) in the calibration results inevitably cause a distortion of the conversion function and the further erroneous measurement results. This paper proposes a theoretical justification for the possibility of generating the conversion function of a measuring transducer with an integrated sensor by processing the results of a multifactorial calibration experiment including random parasitic errors. Experimental results are provided to illustrate the effectiveness of the proposed calibration results processing technique, which allows obtaining the correct conversion function in the conditions of distorted initial data.
Using the capabilities of computer modeling in the software and hardware complex “Safe City”
Authors: Kaliuzhnyi A N , Shurukhnov N G
Published: July 2020

In this article, the authors consider the possibility of using the Safe City software and hardware complex to ensure human safety and security when living within specific territories. The prospects and results of using ICT and mathematical modeling of processes occurring in a certain territory are substantiated. Attention is drawn to the subsystem “Environmental Safety” of the hardware-software complex “Safe City” and the possibility of its use by law enforcement agencies. The approaches to the assessment and mathematical modeling of geodynamic risks arising in a particular territory are investigated. We studied the negative phenomena affecting a person and recorded by means of the APK “Safe City”. The factors contributing to the formation of geodynamic risks in certain territories are analyzed. Forms and methods of using the results of computer modeling of the processes of geodynamic movements in the activities of law enforcement agencies are substantiated. The tasks and functions of law enforcement bodies that are to be aided by mathematical modeling of geodynamic processes in specific territorial systems are highlighted.
Overview of electro physicochemical methods for deburring small-sized high-precision details of coaxial radio components
Authors: Karlina Yu I , Kargapoltsev S K , Gozbenko V E , Karlina A I , Leonovich D S
Published: July 2020

Details of coaxial radio components are small-sized, having high accuracy requirements of up to 7 qualifications, and construction with hard-to-reach surfaces. Burrs on these parts are not allowed by the technical requirements. It is not possible to exclude the appearance of burrs at the stage of blade machining. For deburring, mechanical and electro physicochemical methods are possible. The article provides an overview of electro physicochemical methods for deburring small-sized high-precision parts of coaxial radio components. The features of the application of these methods for these parts, their advantages and disadvantages are given.
Power conditioning unit with independent extreme power control for two sections of small spacecraft solar arrays
Authors: Kiselev P V
Published: July 2020

the article analyzes the main approaches applied in the development process of power conditioning unit (PCU) model to ensure the efficient power use of non-orientable solar arrays for small satellites operated in low Earth orbits with altitudes ranging from 300 to 1500 km. Particular attention is paid to the description of PCU structure choice, as well as the way to achieve the technical specification goals, such as efficiency factor and specific power. A conclusion is made that the optimal structure to ensure PCU efficiency and reliability is the one with a series regulator and section-by-section solar array power extreme control. It is noted that this structure will make it possible to receive power from solar array sections regardless of the difference in temperature and illumination between them. Based on the quantity and duration analysis of the solar battery charge and discharge cycles, the charge and discharge modes of the batteries are defined as basic ones, so the efficiency factor in these modes is maximized. The results of the study described in the article can be used by enterprises specialized in developing small satellites and power conditioning units as a stepping stone for developing a PCU flight model to ensure the efficient power use of non-orientable solar arrays for small satellites.
Modeling a composite assembly for repair of trunk pipelines
Authors: Mukhametzyanov Z R , Kulakov P A , Rubtsov A V , Churakov Yu A
Published: July 2020

The article considers the issue of the efficiency of the use of composite materials in the repair of trunk pipelines. During the study, simulation experiments were carried out using the Solidworks program for the main product pipeline under excess pressure P = 4 MPa. Altogether, eight situations were studied that differed in the amount of composite material applied to the defect. The criterion for determining the number of situations was determined by the number of layers of the composite material at which a favorable situation for the operation of the pipeline occurs. As a result of the experiments, the dependence of the stress-deformed state on the number of layers of the composite material deposited at the defect site is obtained. This dependence allows us to recommend a certain composition of the composite unit for repair of trunk pipelines. The research results obtained have the prospect of their further application in the development of a standard program for the repair of trunk pipelines using composite materials.
The influence of the rocks material composition on the reservoir properties of the reservoir
Authors: Malyarenko A M , Kotenev Yu A , Mukhametshin V Sh , Bogdan V A , Kotenev A Yu , Blinov S A , Umetbaev V G
Published: July 2020

High oil reserves characterize most fields in Western Siberia. However, along with this, zones of the productive formation that are poorly involved in development and production wells, in which products with a high proportion of water are produced, are distinguished within limits. For understanding the causes of this problem, it is important to consider the material composition of the reservoirs. In particular, it is necessary to consider the clay content, which is associated with the reservoir properties of rocks, hydrophilicity, hydrophobicity and, accordingly, with wettability. The article examined and analyzed a representative sample of core study of two wells in the Gubkinsky oil and gas region, which suggested the possible reasons for the lack of oil reserves.
To the study of the dynamics of layered structures with plane inclusions
Authors: Pavlova A V , Telyatnikov I S
Published: July 2020

We consider the problem of vibration for a layered package with defects such as hard inclusions on interlayer interfaces. Using the factorization approach, we obtain recurrence relations for the construction of functional-matrix equation systems for problems of elastic vibrations of a multilayer structure with a finite number of planar defects. When studying the resonance properties of the structures under consideration, the obtained representations of matrix kernel symbols of the integral equation systems allow us to implement numerical algorithms and construct the root and polar sets of their elements and determinants for a wide range of problems. The approach presented in this work makes it possible to efficiently study vibrational regimes for multilayer structures taking into account non-ideal interlayer contact. The developed scheme can also be applied to the case of an arbitrary number and alternation of parallel cracks and inclusions. Theoretical results can find applications in engineering practice when studying the strength properties of designed materials, when assessing the operational characteristics of composite structural elements, etc.