bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing Slump Flow, Specific Gravity, and Compressive Strenght Material Properties of Self Compacting Concrete (SCC) with Glass Waste Powder
Authors: Noorzyafiqi D , Srisunarsih E , Sucipto T L A , Siswanto B
Published: March 2021

Self Compacting Concrete (SCC) is the latest and advanced technology in the field of concrete technology. SCC is an innovative type of concrete, one of which has properties flowable. In this study, one of the innovations in the use of glass bottles as a substitute some cement for SCC. This research was conducted to determine the effect of glass waste powder as partial substitute for cement on slump flow, specific gravity, and the compressive strength of concrete aged 14 days SCC. The mix design used was Okumura’s Simple Mix Design [1], water-per-powder ratio 0.35, and dosage superplasticizer 1%. Variation of glass waste powder 0%, 5%, 10%, 15%, 20%, 25%, and 30% of the weight of cement, the size of the waste glass powder is through the filter no. 100 and stuck in the filter no. 200. The test object in this study uses a cylinder with diameter 15 cm and height 30 cm. The flowability test is carried out when the concrete is fresh. For hard concrete, specific gravity and compressive strength tests are carried out at the age of 14 days. The result of replacing glass waste powder as a substitute for some cement has a significant effect on the slump flow value of 85%. Slump flow in fresh concrete mixture with various glass waste powder 5%, 10%, 15%, and 20% reach the standard [2]. Replacement of glass waste powder as a substitute for part of cement has a significant effect on the specific gravity concrete amounting to 69.6%. Specific gravity concrete in this study fulfills the requirements for structural normal specific gravity[3]. On the compressive strength of concrete aged 14 days, glass waste powder has a significant effect of 86.2%. Compressive strength has a maximum compressive strength of 35.322 MPa, with an optimal percentage of glass waste powder as a substitute for partial cement is 10.464%.
Effect of concrete strength configuration on the structural behaviour of reinforced graded concrete beams
Authors: Pratama M M A , Umniati B S , Nindyawati N , Margaretha D I , Suhud R K , Puspitasari P , Permanasari A A
Published: March 2021

Earlier experimental studies of graded concrete mentioned that by combining 2 (two) concrete mixes with distinguished strength, it created an advanced material with a higher modulus of elasticity. Research related to the application of graded concrete on beam elements has been conducted several times by researchers and produced numerous important findings. Research using finite element has been conducted to analyse the extensive use of graded concrete when applied to reinforced concrete beams with various configurations. This research aims to validate the findings of previous research in experimental works. Graded concrete beams made of 2 (two) layers of concrete mixes were tested. The difference between the two types of testing beams is in the configuration of concrete placement. The beams were tested under four-point bending procedure to obtain load-deflection data. The results show that the placement of higher concrete strength in the tensile fibres provides a better beam resistance to cracks indicated by an increase in the point at which the steel reinforcement experiences yielding. The greater the tensile strength of the concrete, the concrete will provide a better bonding to the steel reinforcement so that cracks can be minimized. A concave pattern is found in the transition area after the first crack. A noticeable curve pattern becomes apparent at beams composed of low concrete strength, whereas in the beam with high concrete strength only created a linear pattern. In terms of stability and structural strength, GBA has superior performance when compared to GAB. GBA tends to be able to continue to maintain the value of structural rigidity until the beam reaches the ultimate condition. Meanwhile, the GAB instantly loses its stiffness and to experience a sudden collapse.
Abstract Thinking Skills of High School Students in STEM Learning: Literature Review
Authors: Hanif Q , Budiyanto C W , Yuana R A
Published: March 2021

Computational Thinking is a skill that must be possessed in STEM learning. The abstraction process is at the core of CT. Abstract thinking is built on ideas and ideas based on experience. From the literature studies that have been read, many have adopted robotics media in education but researchers have not found the use of robotics media in the field of biology at the high school education level. Therefore, a systematic literature review was conducted to find out the latest developments regarding the topics in this literature. Therefore, this study highlights 3 points of the application of robotics in high school education to hone students’ abstract thinking skills. First, STEM can facilitate abstract thinking. Second, the role of robotics in education which is proven to increase student motivation. The third is the implementation of STEM learning in high school education. The search was limited to literature data-based publication outlets such as DOAJ, ERIC, Science Direct, and Google Scholar to maintain credibility. While previous research shows that students’ abstract thinking skills tend to be lower when using conventional learning. So that we need an approach such as STEM which is useful for solving a problem by utilizing symbols and is more effective in exploring concepts.
An experimental study into the effect of fuel on step micro-combustor to the flame stability characterization
Authors: Saputro H , Ariyanto E D , Wijayanto D S , Muslim R , Fitriana L , Munir F A
Published: March 2021

Energy demand in the form of portable devices to supply electronic equipment increases every year. Micropower Generator is an alternative solution for portable energy generation. The most crucial component in micropower generation is micro-combustion. The problem faced in micro-combustion is the presence of a stable flame in the combustor. This study aims to produce flame stability on the combustor by using several fuels such as acetylene gas and propane gas. The micro combustor used in this study is a cylinder type with an inlet diameter of 3.5 mm, an outlet diameter of 4.5 mm, and a wall thickness of 0.5 mm. The micro-combustor is made of stainless steel with a burned region of 10 mm and an unburned region of 40 mm. The results showed that the combustor wall’s temperature with propane fuel reached the highest average temperature at 182.45°C, while 113.20 °C for acetylene fuel.
A Case Study: Gap Competency Between Mechanical Engineering Graduates of Vocational High School and The Demand in Workplace
Authors: Saputro H , Ranto  , Bugis H , Muslim R
Published: March 2021

This study explores the workplace competencies, especially in the production machine operators, and finds the existing gap between the competency of mechanical engineering graduates of Vocational High School (Indonesian: Sekolah Menengah Kejuruan; abbreviated as VHS) and the demanded skills in the workplace. The research method employed in this research is the qualitative-explorative research method. In this research, it can be acknowledged that in a broader aspect, the competencies of the mechanical profession of motorcycles, cars, and operators of production machines can be clustered into three groups of skills: base, core, and supporting competencies. Based on the four competencies’ competency map, the vocational school graduates’ basic competencies are unfulfilled in the production workshop: (1) reading the technical drawing and (2) using the hand tools. Moreover, VHS graduates of the mechanical engineering department are still shortage of core competencies, hence still occupying at “lack of comprehension” level equal to more than 33%. On the other hand, the vocational school graduates’ supporting competency is in a minor percentage, according to the workshop’s head, chief engine operator, and senior operator in the workshop.
The Influence of Gross Domestic Product and Human Development Index on CO2 Emissions
Authors: Bieth Rangel Chris Eko
Published: March 2021

Economic development runs hand in hand with a reduction of durability and functionality of the environment. Development-oriented in the pursuit of growth is too often ignored aspect of environmental management. Development that aims to prosper the people, ultimately becoming the life support system of the destroyer (in this case the environment). The object of this research is to analyze the effect of Gross National Product and the Human Development Index against the CO2 Emissions in 6 countries of the ASEAN countries and Japan. The methods used in this research is a panel data regression is a combination of the time series and cross section of 6 countries of ASEAN countries and Japan. The results of this study found that Gross National Product effect was positive but not significantly to CO2 while Human Development Index positive and insignificant effect against CO2.
Development Needs Analysis of Teaching Materials for Improving Critical Thinking Skills Students in Century 21
Authors: Perdanasari Ayu , Sudiyanto  , Sangka Khresna Bayu
Published: March 2021

Critical thinking is a skill students need in 21st century learning. These skills will be useful for students to solve problems and lead to lifelong learning. Therefore, it needs teaching materials that fit the needs and demands of the curriculum. This study aims to analyze the need for developing teaching materials to improve critical thinking skills. Teachers, students and documents become subjects in research. The method of research used qualitative research. The findings show that the teaching materials used have not led to improve students’ skills. Therefore, it is necessary to develop teaching materials based on the results of needs analysis in this research.
The Impact Adobe Flash Media in Learning Economics
Authors: Fandini Elma Ayu Nur , Siswandari  , Kristiani
Published: March 2021

This study aims to present the extent of the influence of Adobe Flash media on economic learning. The problem that exists is that there are still many schools that have not implemented varied learning media and the learning media used are less attractive so that they have a less than optimal impact on students. This research method is literature review study. The findings in this article present an increase in student motivation, creative thinking, critical thinking, literacy and student learning outcomes. The results of the literature review show that through the use of Adobe Flash media will have an effect on increasing student motivation, creative thinking, critical thinking, literacy and learning outcomes. The advantage of flash media is that it is one of the most popular web animation technologies, has good quality, and can be displayed on many media. However, Adobe Flash media has a drawback, namely that you have to memorize commands for beginners and only use them online. Literature study that examines Adobe Flash media in increasing the effectiveness of the economic learning process and students’ abilities in the economic learning process.
Online Mathematics Learning during the Covid-19 Pandemic
Authors: Wardani E R , Mardiyana  , Saputro D R S
Published: March 2021

This research is a descriptive quantitative research that focuses on evaluating learning using online media with the aim of (1) knowing the effectiveness of online mathematics learning that is expected by class XI students of SMA Negeri Kerjo as an effort to suppress the spread of covid-19 in the school environment; (2) knowing the obstacles in online learning; (3) knowing student suggestions to increase the effectiveness of online mathematics learning. The study population was all students of SMA Negeri Kerjo. The research sample was students of class XIA1 selected using simple random sampling by considering population homogeneity. Data were collected using an online questionnaire. The data were analyzed using descriptive statistical analysis. The results are(1) students rated online mathematics learning as ineffective (46%), very ineffective (27%), effective (17%), and very effective (10%); (2) the obstacles faced by students were the unstable internet network, limited internet quota, lack of time in discussion and assignment collection, and too many assignments; (3) to improve online mathematics learning during the Covid-19 pandemic, suggestions from students that need to be considered: learning through easy media, providing simple material, minimizing sending video to save quota, extending assignment time, and reducing assignments.
Semiotic Analysis of Mathematics Problems-Solving: Configure Mathematical Objects Viewed from High Mathematical Disposition
Authors: Claudia L F , Kusmayadi T A , Fitriana L
Published: March 2021

The main purpose of this study was to describe the semiotic of students in solving mathematical problems with analysis using mathematical objects. In learning, mathematics was inseparable from signs and symbols. Mathematics in general was a subject that contains symbols, numbers, graphs, tables, diagrams. We used semiotic to analyze the configuration of mathematical objects (language, problems, concepts, procedures, propositions, and arguments). Subject of high school students in the City of Kediri using a technique is called qualitative descriptive and the subject has been selected according to a purposive sampling technique, and then fourteen students has been chosen who represent the category of high mathematical disposition. The results of this study describe semiotic students, who are students with high mathematical disposition obtaining all indicators of semiotic.
Analysis of Students’ Mathematical Communication Ability Based on Kolb’s Learning Styles of Converger and Diverger Type
Authors: Rohmanawati E , Kusmayadi T A , Fitriana L
Published: March 2021

Mathematical communication ability is an ability that every student must-have. Without mathematical communication ability, students will not be able to convey their mathematical ideas to others. This research aims to describe a mathematical communication ability of students who have Kolb’s Learning Styles of converger and diverger type. This study used a qualitative descriptive method. The subjects of this research are 8thgrade Junior High School students who were selected using purposive sampling. The data from this research were obtained from Kolb’s learning style questionnaire, mathematical communication test, and an interview. The data validity used the triangulation method. The data analysis was performed through data reduction, data presentation, and conclusion. The result shows that the converger type student can express mathematical ideas through writing and to visually describe it, able to interpret the ideas by writing steps of problem-solving sequentially and systematically, and able to use mathematical notations in writing problem-solving. While the diverger type student is able to express mathematical ideas through writing and to visually describe it, and able to use mathematical notations in writing problem-solving.
Junior High School Students’ Mathematical Communication Ability in terms of High-Level Interpersonal Intelligence
Authors: Rivai M A , Mardiyana  , Slamet I
Published: March 2021

Interpersonal intelligence is a person’s ability to communicate and interact with others consciously in different environments. The difference in the level of interpersonal intelligence affects communicating with other students. Mathematical communication skills are the ability to convey mathematical ideas either orally, in writing, or in motion. The purpose of this study was to see the mathematical communication skills of students with high interpersonal intelligence. The type of research used is descriptive qualitative with instruments in the form of tests of mathematical communication skills, interpersonal intelligence questionnaires, and interviews. The subjects of this study were 2 students from class VIII SMPN 2 Baki who have high interpersonal intelligence selected by purposive sampling. The triangulation used is method and source. The results of this study indicate that students with high interpersonal intelligence can meet all indicators of mathematical communication skills. However, some students have not fulfilled one of the indicators of mathematical communication skills, namely expressing real objects, situations, and everyday events into the form of mathematical models. One of the contributing factors is that students do not understand the information on the story questions presented, so students must be asked story questions related to everyday life.
XII International Conference on Mathematics, Science and Technology Education
Authors: Kiv A E , Soloviev V N , Semerikov S O
Published: March 2021

This paper represents a preface to the Proceedings of the XII International Conference on Mathematics, Science and Technology Education (ICon-MaSTEd 2020) held at the Kryvyi Rih State Pedagogical University, Ukraine, 15–17 October 2020. Background information and the organizational structure of the meeting, and acknowledgements of the contributions of the many people who made the conference a success are presented.
Comparative Geometry in distance education
Authors: Lénárt I
Published: March 2021

I have been working on an educational project called Comparative Geometry for decades. The project is based on teaching and learning plane geometry and spherical geometry simultaneously, mainly through direct experimentation with hands-on tools, and intensive use of discussion between classmates. This work has gravely been affected by the changes that occurred two months ago because of the pandemic, still causing emergencies in many areas of education. In this article, I describe how I tried to adapt the work of a university course to an emergency; the methods by which I enabled direct experimentation and personal communication that were not possible in the given situation; my efforts to reduce the drawbacks of the situation and take advantage of the potential benefits.
Learning by experimenting as a good way to effective and student friendly mathematics education – experiences from Young Explorer’s Club
Authors: Rybak A
Published: March 2021

Students in many countries have problems with learning of mathematics. Many students do not like mathematics. Teachers and parents are mostly aware that the style of teaching of mathematics and “the atmosphere” around mathematics are the main reasons for this state. For the society it is clear that something must be changed. Maybe methods of teaching, maybe the whole system? Copernicus Science Centre in Warsaw 18 years ago proposed the idea of Young Explorer's Club (YEC) as the environment where students can discover knowledge by making experiments. Learning by experimenting, by own activity of learners makes the whole educational process more interesting and less frustrating for students. This also applies to mathematics education. Experiences from mathematical Young Explorer's Clubs established at the Centre for Creative Mathematics Learning at the Faculty of Mathematics University of Bialystok as the possible way to more effective mathematics education will be presented in the paper. Experimenting and using functional strategy of teaching of mathematics is the basic form of activity in the Clubs.
Training pre-service mathematics teacher to use mnemonic techniques
Authors: Drushlyak M G , Semenikhina O V , Proshkin V V , Sapozhnykov S V
Published: March 2021

The article reveals the issue of the appropriateness of training pre-service mathematics teachers to use the techniques of mnemonics in professional activities. This issue is caused by the intensification of the educational process, when the amount of information accumulated by mankind is many times greater than the amount of knowledge that can be learned by a particular person. It is established that in the process of teaching mathematics, mnemonics should be used as a way of perceiving new information due to the formation of associative connections using special methods and techniques. The expediency of training pre-service mathematics teachers to use various methods of mnemonics (“Binding”, “Transformation”, “Amplification”) is substantiated. A positive attitude of mathematics teachers towards the use of mnemonics techniques was revealed, as well as a low level of students' understanding of the advisability of using mnemonics techniques in professional activities. The classification of software used to create visual models is presented. A training was developed and introduced into the practice of university education on the development of mnemonic techniques for the presentation of educational mathematical material. The prospects of scientific research through the development of methodological support for the training of pre-service mathematics teachers to use the techniques of mnemonics in professional activities are determined.
Predictive model of heavy metals inputs to soil at Kryvyi Rih District and its use in the training for specialists in the field of Biology
Authors: Savosko V , Komarova I , Lykholat Yu , Yevtushenko E , Lykholat T
Published: March 2021

The importance of our research is due to the need to introduce into modern biological education methods of predictive modeling which are based on relevant factual material. Such an actual material may be the entry of natural and anthropic heavy metals into the soil at industrial areas. The object of this work: (i) to work out a predictive model of the total heavy metals inputs to soil at the Kryvyi Rih ore-mining & metallurgical District and (ii) to identify ways to use this model in biological education. Our study areas are located in the Kryvyi Rih District (Dnipropetrovsk region, Central Ukraine). In this work, classical scientific methods (such as analysis and synthesis, induction and deduction, analogy and formalization, abstraction and concretization, classification and modelling) were used. By summary the own research results and available scientific publications, the heavy metals total inputs to soils at Kryvyi Rih District was predicted. It is suggested that the current heavy metals content in soils of this region due to 1) natural and 2) anthropogenic flows, which are segmented into global and local levels. Predictive calculations show that heavy metals inputs to the soil of this region have the following values (mg ⋅ m2/year): Fe – 800-80 000, Mn – 125-520, Zn – 75-360, Ni – 20-30, Cu – 15-50, Pb – 7.5-120, Cd – 0.30-0.70. It is established that anthropogenic flows predominate in Fe and Pb inputs (60-99 %), natural flows predominate in Ni and Cd inputs (55-95 %). While, for Mn, Zn, and Cu inputs the alternate dominance of natural and anthropogenic flows are characterized. It is shown that the predictive model development for heavy metals inputs to soils of the industrial region can be used for efficient biological education (for example in bachelors of biologists training, discipline “Computer modelling in biology”).
Comparisons of performance between quantum-enhanced and classical machine learning algorithms on the IBM Quantum Experience
Authors: Zahorodko P V , Semerikov S O , Soloviev V N , Striuk A M , Striuk M I , Shalatska H M
Published: March 2021

Machine learning is now widely used almost everywhere, primarily for forecasting. In the broadest sense, the machine learning objective may be summarized as an approximation problem, and the issues solved by various training methods can be reduced to finding the optimal value of an unknown function or restoring a function. At the moment, we have only experimental samples of quantum computers based on classical-quantum logic, when quantum gates are used instead of ordinary logic gates, and probabilistic quantum bits are used instead of deterministic bits. Namely, the probabilistic nature problems that provide for the determination of a certain optimal state from a large set of possible ones on which quantum computers can achieve “quantum supremacy” – an extraordinary (by many orders of magnitude) reduction in the time required to solve the task. The main idea of the work is to identify the possibility of achieving, if not quantum supremacy, then at least a quantum advantage when solving machine learning problems on a quantum computer.
Formation of communication and teamwork skills of future IT-specialists using project technology
Authors: Pavlenko M , Pavlenko L
Published: March 2021

The subject of the study is the formation of communication and teamwork skills of future IT-specialists, using project technology in teaching the administration of computer systems and networks. Content analysis of research has shown that communication and teamwork skills are the most requested and necessary soft skills for future IT professionals. It is offered to use project technology of training for their formation. This technology consists of the approaches and tools application used in real-world software development. To implement this technology, we propose to use mind maps for design. The organization of the working process on the project is implemented in Jira Software, Asana or Trello. Communication among project participants should be implemented with the help of several means: video chats (Zoom, Skype, Google Meet) and written communication in corporate messengers (Slack, Zulip). Experimental verification has shown the efficiency of the proposed design technology implementation.
Constructing personal learning environments through ICT-mediated foreign language instruction
Authors: Kupchyk L , Litvinchuk A
Published: March 2021

The article deals with the concept of student-centred Personal Learning Environment (PLE) in the context of higher education, which is used as a means of transforming foreign language learning and teaching practices. It aims to reveal the opportunities for creating PLEs through incorporating Information and Communication Technology (ICT) in the process of foreign language education. The study focuses on the roles of teachers and students of non-language University majors in designing efficient learning environments highly adapted to changing objectives and student personal needs. The authors reveal the unlimited potential of ICT in constructing PLEs for both in-class activities and informal learning, providing a scope of practical student activities, which imply their active engagement both in and outside the classroom, as well as constructing a flexible, personalized, time and space independent learning environment. Students, teachers, ICT, which is a set of resources based on the use of educational technology tools thoroughly selected and organised in order to manage the content, applying relevant methods of teaching and learning strategies, as well as a learning process, are all regarded as constituents of PLEs aimed at mastering four foreign language skills when taking the course “Foreign Language for Specific Purposes”: reading, listening, writing and speaking within personal, academic, and field-related contexts.
The formation of educational environment in foreign language training of energy engineering students by means of project technology
Authors: Horbatiuk R M , Bilan N M , Sitkar O A , Tymoshchuk O S
Published: March 2021

The article deals with the results of experimental work concerning the educational environment formation that is focused on the foreign language training of future energy engineering students. Project learning technology is chosen as the means of formation. A model of the educational environment for the metalanguage studying of the speciality of energy engineering students has been developed. In the educational process, educational projects with elements of professional orientation were implemented in accordance with the subject of the discipline “Business Foreign Language”, and the language abilities and internal potential of students were taken into account. The preparedness of energy engineering students to integrate knowledge of professionally oriented disciplines into a foreign language environment for solving project tasks of communicative nature has been determined. According to the results of the pedagogical experiment, it was established that in the process of project activity the mastering level of lexical and speech competences as the components of foreign language competence of students has significantly increased. The developed educational environment is characterized by differentiation, individuality, independence, autonomy, informativeness, creativity, which allows to create the necessary conditions for successful learning of foreign language, development of creative thinking, communicative skills of energy engineering students, formation of foreign, communicative, professional, informational, project, research competencies.
Organization and conduct of classes in educational institutions during distance learning
Authors: Franchuk N P , Prydacha T V
Published: March 2021

The article considers the use of cloud technologies during distance learning. The implementation of the mechanism of distance learning in general secondary education in two areas is described: distance form as a separate form of education and the use of distance learning technologies in the organization of education in various forms (day, evening, correspondence, etc.). The software for the organization of distance learning of pupils and students is listed. Examples of development of own electronic educational materials for teaching mathematics and computer science are given.
The freight pneumatic elevators as a new form of transport
Authors: Nikolayev Yu A , Taranov A V , Mekhtiyev A D , Neshina Y G
Published: March 2021

This article addresses the problem of ensuring high reliability and safety performance of freight elevators. Rope elevator hoists exist more than one hundred years and have become very common, but it is very difficult to achieve their operational efficiency. The authors propose a solution to the problem - the introduction of a fundamentally new type of transport - pneumatic lifting, which capable provides high technical and economic performance. At the specialized enterprise «Pnevmopod”yem» a small-lot manufacture of new import-substituting equipment for hoisting in building sestablished. The authors present the advantages and the principle of operation of the developed pneumatic elevator. Essential advantage of this machine is the safe work which is incorporated in its design. Considerable attention is paid to the results of tests of cargo pneumatic elevator. The authors come to the conclusion that the design of a freight pneumatic elevator makes it possible to use it successfully for transporting cargo in buildings and structures for various purposes, to reduce capital investments in construction, installation and operating costs. The absence of foreign analogs will allow selling pneumatic lifts not only in Kazakhstan, but also in the countries of the former USSR.
Emergency response robotic platforms
Authors: Uvarov N A , Syryamkin V I
Published: March 2021

This paper describes the development of an autonomous robotic platform capable of undertaking rescue missions on rough terrain and other unpredictable environments. The key difference of this platform is the lack of LIDAR system and an algorithm that relies primarily on ultrasonic and optical sensors. As a result, two platforms were created, a fully autonomous drone and a scout bot that operate effectively together.
The main structural element of a reinforced concrete supports: mathematical modeling of mechanical vibrations
Authors: Dymov G A , Belichenko V P
Published: March 2021

The problem of mathematical modeling of a reinforced concrete supports mechanical vibrations is considered. The basic vibrations of the main structural element (a road) are taken into account. The eigenfrequencies of the first three vibration modes of the rod are determined without and with prestressing of the rod. Participation factor of the basic, second and third modes is investigated.
A fast simulation package for STCF detector
Authors: Shi X.-D. , Zhou X.-R. , Qin X.-S. , Peng H.-P.
Published: March 2021

A Super Tau Charm Facility (STCF) is one of the major
options for the accelerator-based high energy project in China in
the post-BEPCII era, and its R&D program is underway. The proposed
STCF will span center of mass energies (√(s)) ranging from 2
to 7 GeV with a peaking luminosity above 0.5×
1035 cm−2 s−1 at √(s)=4.0 GeV, and will
provide a unique platform for tau-charm physics and hadron physics.
In order to evaluate the physical potential capabilities and
optimize the detector design, a fast simulation package has been
developed. This package takes as inputs the response of physical
objects in each sub-system of the detector including resolution,
efficiency as well as related variables for the kinematic fit and
the secondary vertex reconstruction algorithm. It can flexibly
adjust the responses of each sub-detector system and is a critical
tool for the STCF R&D program.
Recharge from glacial meltwater is critical for alpine springs and their microbiomes
Authors: Miller Jordyn B , Frisbee Marty D , Hamilton Trinity L , Murugapiran Senthil K
Published: March 2021

The importance of glacier meltwater as a source of mountain-block recharge remains poorly quantified, yet it may be essential to the integrity of alpine aquatic ecosystems by maintaining baseflow in streams and perennial flow in springs. We test the hypothesis that meltwater from alpine glaciers is a critical source of recharge for mountain groundwater systems using traditional stable isotopic source-identification techniques combined with a novel application of microbial DNA. We find that not only is alpine glacier meltwater a critical source of water for many springs, but that alpine springs primarily supported by glacial meltwater contain microbial taxa that are unique from springs primarily supported by seasonal recharge. Thus, recharge from glacial meltwater is vital in maintaining flow in alpine springs and it supports their distinct microbiomes.
Mobility of ground transport and technological vehicles
Authors: Belyakov V V , Mazunova L N , Markovnina A I
Published: March 2021

The article provides a definition of the mobility of ground transport vehicles and transport and technological complexes. Mobility is defined as an integral characteristic of structural and operational, economic, ergonomic and environmental properties of ground mobile systems and complexes. Also, mobility characterizes the competitiveness of objects as a product. A structural diagram of the hierarchy of control tasks for transport and technological vehicles is given containing four tasks related to the field of design parameters: maintaining mobility, maintaining directional orientation, maintaining speed, eliminating critical situations when moving a transport and technological system; and also the task: to ensure environmental safety; ensuring nominal economic efficiency and ensuring the comfort of the transport and technological system.
A method for constructing a global motion path and planning a route for a self-driving vehicle
Authors: Sinodkin A A , Evdokimova T S , Tiurikov M I
Published: March 2021

The article presents methods for constructing an unmanned vehicle (UV) motion path in an environment with obstacles to solve the problem of finding a path for a non-holonomic vehicle in an environment with obstacles. A combined approach is described and individual components are considered that allow solving the problem of planning a path for a non-holonomic vehicle. The practical use example of the combined approach for solving the problem of planning the UV path is given.
A method to improve forwarders’ energy performance and environmental compatibility
Authors: Kotiev G O , Klubnichkin E E
Published: March 2021

The article presents the results of theoretical justifications of a method improving energy performance and environmental compatibility of the load-haul-dump vehicles (forwarders) used during timber cut-to-length operations.
A methodology for evaluating the efficiency of driving a truck
Authors: Umirzokov A M , Mambetalin K T , Saidullozoda S S , Berdiev A L
Published: March 2021

The article considers the issues of evaluating the efficiency of converting thermal energy into mechanical work when operating pit vehicles - BELAZ-7540B dump trucks in mountain conditions and the role of the driving skills in this process. The article also defines the efficiency of driving a vehicle, based on which it presents a methodology and mathematical models for evaluating the driver’s efficiency. At the same time, the basis is formed by several operational indicators, out of which the most important ones for mountain operating conditions of heavy-duty trucks - dump trucks are energy, economic and reliability indicators. The driver’s efficiency is evaluated by the energy and economic indicators based on the trip fuel consumption and the performance of the vehicle - dump truck per shift. The efficiency of driving a heavy-duty truck - a dump truck by the material costs indicator is evaluated by the consumption of spare parts and repair and maintenance materials. The driver’s efficiency is evaluated by the reliability indicators based on the specific time, labor, and money costs spent on eliminating operational and resource failures.
Conceptual model of the automated pedestrian simulation system for unmanned vehicles and ADAS systems testing
Authors: Tumanov A A , Zolotov A V , Fedosova L O , Sizov A Y
Published: March 2021

This article is devoted to the issue of creating the concept of an automated system for simulating pedestrians on the road surface, intended for testing unmanned vehicles and active driver assistance systems. The article examines in detail the prerequisites for the creation of such a system and its relevance for Russia. The existing analogues of this system are demonstrated, their strengths and weaknesses are analyzed. A conceptual model of the system is proposed, its functional capabilities are described, the design of the main units and components of the system is presented. Two possible options for the operation of this system during testing are considered: at regulated and unregulated pedestrian crossings. Variants of test methods in accordance with the named options are proposed.
Determining of optimum composition of water-fuel mixture for a spark-ignition internal combustion engine with electronic control
Authors: Kartoshkin A P , Birykov A L , Busikov Sh V , Sergeev D G , Plotnikov S.A.
Published: March 2021

The relevance of the study is stipulated by the necessity for determining of optimum composition of water-fuel mixture (WFM) for a spark-ignition internal combustion engine with electronic control. The objective of the study is the determining of the optimum composition of water-fuel mixture (WFM) during the operation of a VAZ-21114 engine which allows for the best quantitative performance specifications. For this purpose, an experimental test fixture was developed, consisting of a KI-2139 electrical brake bench with a pendulum arm machine and an “AVTOTEST-02.03” 5-component gas analyzer, with equipment for bench testing in accordance with the requirements of GOST 14846-81 “Automotive engines. Bench test methods”. As a result, for the first time, optimum quantitative WFM composition was obtained for operation of VAZ-21114 spark-ignition engine with electronic control providing for the best quantitative performance specifications. The analysis of the obtained data demonstrates lowering of the concentration of toxic exhaust gas (EG) components of the engine, specific effective (ge) and hourly (Gm) fuel consumption rate, as well as the EG temperature (Toe) during its operation by the external rpm vs. load curve within the utilization range of WFM with 0 to 12% water content. At water content growth in the WFM from 12 to 20%, a growth of carbon monoxide (CO) and unburnt hydrocarbons (CH) in the EG is observed, as well as a growth ofgeandGm. The minimum quantitative values of the parametersCO, CH, NOx, Toe, geandGmwere: 6.0 and 1.65% ofCOat water content in WFM of 10 and 13%, respectively; 173 and 142.5 ppm ofCHat 10% water content in WFM; 113 and 215 ppm ofNOxandToe650 and 730 К at up to 20% water content in WFM;ge330 and 303 g/kWh at 12.5 and 11.5% water content in WFM, respectively,Gm6.5 kg/h at 11.5% water content in WFM. The maximum quantitative value of the effective engine powerNeof 44.2 kW was obtained with WTM with 20% water content. The obtained results demonstrate that, for the operation of a spark-ignition type VAZ-21114 engine with electronic control, the WTM should contain 9…12% water as an optimum providing for achievement of the best quantitative performance values.
Ensuring reliability of electronic control of engine fuel supply subsystem in operation
Authors: Bazhenov Y , Bazhenov M , Kalyonov V
Published: March 2021

The paper presents results of a study of operational reliability of electronic control of an automotive engine fuel supply subsystem. Impacts on the structural elements of the subject subsystem stipulated by physical and chemical processes of heat transfer and dissipation, absorption of magnetic and electric fields, wear and tear, etc., leads to occurrence of various kinds of damage in them. Causes of the subsystem getting inoperable and the effect of failures of its elements on the engine operation are revealed. Considerable attention is paid in the paper to the diagnostics of the technical state of order of the sub-system which must be performed in scheduled car maintenance intervals in accordance with the developed method and algorithm. The deviation of the fuel pressure in the fuel rail from the setpoint in the electronic control unit was taken as the diagnostic parameter for the evaluation of the technical condition of the subsystem. Using Microsoft Excel, an analytical equation was selected that describes the dependency of the diagnostic parameter deviation versus the running time of the vehicle allowing for the substantiation of its rated values. The results of the performed studies were tested and introduced into the technological processes of maintenance and repair of Peugeot cars of “Auto Tract Peugeot” dealership, Vladimir City.
Modeling of the total disturbing effects on the transmission elements from movement on different support bases and the engine
Authors: Leliovsky K Y
Published: March 2021

For the purpose of determining and predicting their mobility in operating conditions, it is necessary to create a comprehensive dynamic model that allows you to determine the parameters of power unit vibrations and torsional vibrations in the transmission, taking into account the relationship between torsional vibrations of the transmission, vertical, longitudinal-angular vibrations of the inertial masses of the vehicle, power unit and transfer case, elastic suspension elements, tires and power unit supports, disturbing effects from road roughness and the running engine. It allows you to determine the values of vibration loading of the body and associated components and aggregates of the vehicle, depending on the physical and technical parameters of the support base and the frequency response (speed of the car).
Modern methods of field tests of driver assist systems
Authors: Toropov Ye I , Trusov Yu P , Vashurin A S , Moshkov P S , Filatov V I , Gnenik M E
Published: March 2021

In view of stringent vehicle safety requirements the automakers are urged to develop and implement electronic driver assist systems (ADAS). However, before starting the mass production, one has to make sure that these systems function correctly and efficiently. The current level of technologies, the simulation modelling allows debugging and testing of operation algorithms for electronic ‘assistants’ in laboratory conditions thereby reducing the costs of the prototype production. This approach is employed at intermediate development stages of the system. At the final stage the ‘traditional’ approach (field tests) is used by the automobile manufacturers, the reason being that the algorithm operation has to be tested in real conditions, and the certification of vehicles with ADAS functionality using methods of simulation modelling is not provided in current state standards. Keeping this in view, the problem arises of creating a measuring unit for geolocation of the vehicle with precision accuracy and synchronized video recording from multiple cameras simultaneously. This article presents the solution developed by employees from NNSTU n.a. R. E. Alekseev as regards the development of such a test system: a schematic diagram of the system is developed; the system is installed on a light commercial vehicle being tested; the system efficiency is checked. The system performance was checked when testing blind spot detectors, lane departure warning system and parking assistant.
Optimization of traffic flow speed in urban conditions
Authors: Kindeyev E A
Published: March 2021

The article is devoted to the problem of more complete use of the traffic network capacity in urban development. The aim of this article is to publish proposals for improving the efficiency of the existing traffic network to reduce the likelihood of traffic jams during high traffic hours. The results of the calculations showed that the maximum bandwidth of the traffic lane is achieved in a certain range of vehicle speeds and depends on the coefficient of adhesion.
Possible solutions to the problem of recycling electric vehicle batteries on the example of global manufacturers
Authors: Kolesnichenko D A , Pechalinov D N , Vyatkin R V , Erofeeva A V
Published: March 2021

The article discusses the methods of recycling and reusing of traction batteries of electric vehicles on the example of global automakers or companies specializing in this topic. Analyzed the legislative rules and regulations for the disposal of spent batteries in different countries. Warranties of electric vehicle’s manufacturers were considered.
Scaling and dynamics of special machines
Authors: Kuklina I G
Published: March 2021

Rotary screw machines (RSM) are widely known as multipurpose vehicles. RSM easily overcome impassable swamps, snow-covered, off-road, ice surface. A significant problem for the creators of vehicles with rotors is the high vibration loads on the operator and machine units, which require multiple experimental studies. A scaled-down model of a vehicle is often used for experiments. The model of the RSM is included in the experiment, replacing not only the object of research, but also the conditions in which it is studied. Strengthening the role of the theoretical side of research, there is a connection between the formulation of the experiment and its results with the object of research. Calculation and calculation of the elements of proportionality is a hard necessity. The article proposes a complex for calculating scale factors when testing vibration loading of machines equipped with screw rotors.
Simulation of conducted emissions in low voltage switching converters
Authors: Vasin A V , Novoselov A A , Samokhvalov E E , Lazarevich S V
Published: March 2021

The article analyzes the computational method used to assess the electromagnetic compatibility of electronic devices in the automotive industry. The analysis is carried out using the example of a pulsed synchronous DC-DC boost converter. Calculations of the conducted interference of the converter, as well as methods of their reduction are presented. This calculation method is performed in the PSpice electrical circuit simulator.
Track snow and swamp-going vehicle with 16 t GVW
Authors: Manianin S E , Lisagov E V , Dmitriev P E , Eremin A A , Vakhidov U Sh , Makarov V S
Published: March 2021

The paper handles the relevance problem of all-terrain vehicle utilization to provide for transportation in hard-to-access territories of the Russian Federation. The most advisable is the utilization of track snow and swamp-going vehicle. It has been demonstrated that, for Russian market, the most relevant is the development of vehicles with 4-6 t load capacity. Analyzed was 5901 track snow and swamp-going vehicle developed in Nizhny Novgorod State Technical University n.a. R.E. Alekseev and “Zavolzhsky Crawler Vehicle Plant” CJSC Demonstrated were better load carrying capacity, soil pressure and motor power performance values compared to the existing similar vehicles. The paper presents the basic specifications.