bluuebunny/crossref_metadata_2025 huggingface dataset:
A new interleaved ultra‐large gain converter for sustainable energy systems
Authors: Nouri Tohid , Shaneh Mahdi
Published: December 2020

By inserting the secondary windings of the coupled inductors in series with the primary of the built‐in transformer at the middle branch, a new concept is introduced for achieving ultra large voltage gain. The secondary and tertiary windings of the built‐in transformer are inserted in the voltage multiplier cell. This configuration not only extends the voltage gain and minimises the voltage stress across power MOSFETs, but also gives a more flexibility to increase the voltage gain by the turns ratios of the built‐in transformer and coupled inductors. Hence, high duty cycle is avoided and low voltage switches can be adopted which reduces the conduction losses. Also, the regenerative diode in each of the phases is connected to the other phase to improve equal current sharing performance. The energy of the leakage inductances is recycled by passive clamps and the high voltage spikes are avoided. Meanwhile, due to the leakage inductances of the magnetic means, the zero current switching of semiconductor devices is provided and the reverse recovery problem is alleviated. Finally, a 600 W prototype with 28–400 V voltage conversion and 97% conversion efficiency is built to demonstrate the performance of the converter.
A TEO‐based modified Laplacian of Gaussian filter to detect faults in rolling element bearing for variable rotational speed machine
Authors: Liu Yi , Jiang Zhansi , Huang Haizhou , Xiang Jiawei
Published: December 2020

Conventional signal processing techniques for fault detection are usually aimed at constant speed conditions. Nowadays, order tracking, especially tacho‐less order tracking is regarded as a valuable tool for extracting fault features under variable rotational speed conditions. Therefore, a teager energy operator (TEO)‐based modified Laplacian of Gaussian filter is proposed to enhance the fault detection behaviour of tacho‐less order tracking. This method consists of four steps: First, multi‐synchrosqueezing transform is employed to estimate and then extract the instantaneous rotation frequency of a shaft. Second, based on the extracted curve, the non‐stationary domain signal is converted into a quasi‐stationary domain by the re‐sampling technique. Third, the obtained quasi‐stationary domain signal is de‐noise by the novel method. Finally, fault characteristic orders are extracted via envelope order spectrum analysis method and the performance is significantly improved. The results of numerical simulation and experimental investigations are performed to validate the superiority of the novel method for fault extraction under variable rotational speed conditions.
Recent Advances in C(sp3)–C(sp3) Cross-Coupling via Metalla­photoredox Strategies
Authors: Yuan Weiming , Zheng Songlin , Hu Yuanyuan
Published: December 2020

Transition-metal-catalyzed carbon–carbon cross-coupling reactions represent a significant achievement in modern synthetic chemistry and they have become indispensable tools for the construction of organic molecules. Despite the important progress in this area, methods for coupling two C(sp3)-hybridized alkyl fragments remain elusive. To date, existing methods have largely relied on using organometallic reagents as the nucleophilic coupling partners, thereby inevitably limiting the compatibility of functional groups. Although cross-electrophile coupling may alleviate the pain somewhat, it is necessary to add a stoichiometric amount of a reductant to complete the catalytic cycle. Recently, the emergence of photoredox-mediated single-electron transmetalation has evoked an ideal paradigm for selectively manipulating C(sp3)–C(sp3) cross-coupling with the unprecedented application of native C(sp3) functionalities instead of organometallic reagents, thus opening a new window for C(sp3)–C(sp3) bond creation. This short review highlights the recent advances in this exciting subfield.

1 Introduction

2 Nickel/Photoredox-Catalyzed C(sp3)–C(sp3) Cross-Coupling

3 Palladium/Photoredox-Catalyzed C(sp3)–C(sp3) Cross-Coupling

4 Copper/Photoredox-Catalyzed C(sp3)–C(sp3) Cross-Coupling

5 Direct C(sp3)–H Alkylation via Metallaphotoredox-Mediated Hydrogen­ Atom Transfer

6 Conclusion and Perspectives
Calcium Homeostasis Comparison in Thermal Burn Patients–Early Tangential Excision and Grafting versus Conservative Management
Authors: Jha Sonika , Goyal Parul , Bhattacharya Sameek , Baranwal Shilpi
Published: December 2020

Introduction With the advent of better burn wound management protocols, early excision and grafting, increased number of burns patients are surviving and entering the struggle of prolonged rehabilitation. Calcium homeostasis and its influence on bone mineralization plays an important role, but it is adversely influenced by the proinflammatory state in burns, leading to hypocalcemia and paradoxical hypercalciuria which, in turn, leads to excessive bony resorption and pathological fractures. The role of early excision in the overall metabolism of calcium is being investigated in the study.

Method This study was undertaken in a tertiary level government-run hospital from February 2018 to August 2019. A total of 28 patients with second degree thermal burns were included. For all patients, fasting serum parathormone levels along with various serum electrolytes like Ca2+, Mg2+, PO4
3- and urinary calcium levels were serially measured from day of admission to 2 months. The first group of 14 patients (Group A) underwent early tangential excision and skin grafting, whereas another 14 patients (Group B) underwent conservative management. All categorical variables were analyzed with the help of Chi square test. A p value of < 0.05 was considered statistically significant.

Result There was a statistically significant improvement in serum parathormone and other electrolytes’ levels in the tangential excision group. Similarly, urinary excretion of calcium also showed favorable results in the group.

Conclusion Early tangential excision and grafting in burns plays an important role in maintaining serum parathormone and calcium levels, leading to prevention of hypercalciuria and optimization of other factors affecting calcium homeostasis.
Tuning MPL signaling to influence hematopoietic stem cell differentiation and inhibit essential thrombocythemia progenitors
Authors: Cui Lu , Moraga Ignacio , Lerbs Tristan , Van Neste Camille , Wilmes Stephan , Tsutsumi Naotaka , Trotman-Grant Aaron Claudius , Gakovic Milica , Andrews Sarah , Gotlib Jason , Darmanis Spyros , Enge Martin , Quake Stephen , Hitchcock Ian S. , Piehler Jacob , Garcia K. Christopher , Wernig Gerlinde
Published: December 2020

Significance

TPO is a cytokine that signals through the receptor MPL (or TPO-R), and is essential for megakaryocyte differentiation and maintenance of hematopoietic stem cells (HSCs). TPO signaling is deregulated in essential thrombocythemia (ET). Here, we engineered diabodies (DBs) against the TPO-R ECD as surrogate TPO ligands to manipulate TPO-R signaling, from full to partial agonism, and that show decoupling of the dual functions of TPO/TPO-R (i.e, HSC maintenance versus megakaryopoiesis). We subsequently discovered that partial agonistic DBs, by reducing the strength of the TPO-R signal, not only preserved HSCs in culture, but also blocked oncogenic signaling in ET. This finding has the potential to improve HSC cultures for transplants, as well as serve as a unique therapeutic approach for ET.
Engineering exosome polymer hybrids by atom transfer radical polymerization
Authors: Lathwal Sushil , Yerneni Saigopalakrishna S. , Boye Susanne , Muza Upenyu L. , Takahashi Shuntaro , Sugimoto Naoki , Lederer Albena , Das Subha R. , Campbell Phil G. , Matyjaszewski Krzysztof
Published: December 2020

Exosomes are emerging as ideal drug delivery vehicles due to their biological origin and ability to transfer cargo between cells. However, rapid clearance of exogenous exosomes from the circulation as well as aggregation of exosomes and shedding of surface proteins during storage limit their clinical translation. Here, we demonstrate highly controlled and reversible functionalization of exosome surfaces with well-defined polymers that modulate the exosome’s physiochemical and pharmacokinetic properties. Using cholesterol-modified DNA tethers and complementary DNA block copolymers, exosome surfaces were engineered with different biocompatible polymers. Additionally, polymers were directly grafted from the exosome surface using biocompatible photo-mediated atom transfer radical polymerization (ATRP). These exosome polymer hybrids (EPHs) exhibited enhanced stability under various storage conditions and in the presence of proteolytic enzymes. Tuning of the polymer length and surface loading allowed precise control over exosome surface interactions, cellular uptake, and preserved bioactivity. EPHs show fourfold higher blood circulation time without altering tissue distribution profiles. Our results highlight the potential of precise nanoengineering of exosomes toward developing advanced drug and therapeutic delivery systems using modern ATRP methods.
Pseudelephantopus spicatus (false elephant's foot).
Authors: Ventosa-Febles Eduardo A.
Published: December 2020

Pseudelephantopus spicatus is a herbaceous plant native to the tropical areas in Mesoamerica, South America, the West Indies and Latin America; it has been introduced to Africa, Southeast Asia and some islands in the Pacific. It is reported to be naturalized in parts of Florida and Thailand. P. spicatus is regarded as a potentially pernicious weed of open ground.. As early as 1948 all available evidence then is said to have indicated that P. spicatus, however interesting as an addition to the adventive flora of the United States, is a potentially injurious weed which should be extirpated if possible before it becomes too thoroughly established.
Pachystachys coccinea (Cardinal's guard).
Authors: Rojas-Sandoval Julissa
Published: December 2020

Pachystachys coccinea is a perennial evergreen shrub cultivated as an ornamental and garden plant for its red flowers on flashy terminal spikes. It has escaped from cultivation and is often found naturalized in damp thickets and at forest edges. Presently, P. coccinea is only listed as invasive in Cuba and as a "common" alien species in Trinidad and Tobago.
Dual-layer graphene based tunable broadband terahertz absorber relying on the coexistence of hybridization and stacking effects
Authors: Lin Rong , He Xiaoliang , Jiang Zhilong , Liu Cheng , Wang Shouyu , Kong Yan
Published: December 2020

With the fast development of terahertz (THz) techniques, THz absorbers have a variety of applications. However, current designs have a series of shortcomings, such as low absorption rate and a fixed and narrow absorption bandwidth. To solve such problems, in this paper, we design a tunable broadband THz absorber, which consists of two layers of graphene structures: the top layer is arrayed with the graphene concentric hexagonal rings and the bottom layer is arrayed with regular graphene hexagon rings; therefore, both layers support hybridization and stacking effects. The coexistence of both effects achieves the absorption rate of over 90% in a broad band from 0.93 THz to 1.80 THz. Moreover, the absorption spectrum can be tuned by adjusting the graphene chemical potential, which is insensitive to both incident angle and polarization. Considering advantages such as a tunable broad absorption band, a high absorption rate and insensitive incident angle and polarization, the proposed dual-layer graphene based tunable broadband THz absorber can be a useful reference for absorber design even in other electromagnetic wavebands.
Explanatory of learning models and vocational teacher perceptions of mechanical engineering during the Covid-19 pandemic
Authors: Widarto W , Sutopo S , Nurtanto M , Cahyani P A , Honggonegoro T
Published: December 2020

This research aims to explore the implementation of the blended learning model and describe the teacher’s perceptions of the constraints and positive impacts of applied learning. This research method uses a descriptive quantitative approach. A total of 41 respondents of mechanical engineering vocational teachers followed the filling of the instruments. Data were collected using a questionnaire in the form of respondent data, learning models used by vocational teachers and perceptions of vocational teachers. The findings of data explanatory research that are different from the implementation of the learning carried out are: (1) online theory learning without practice tends to use the Cooperative Learning of 14.63% and Problem Based Learning of 12.20%, (2) online theory learning with online practice, tends to use the Project Based Learning of 12.20%, (3) Online theory learning with offline practice, tends to use the Project Based Learning of 14.63%, and (4) learning with offline practice tends to choose inquiry learning and Project Based Learning of 2.44%. The main constraints that serve teachers are internet access and limited network availability, the positive impact on the general is the use of ICT. An important finding in this study is that vocational teachers must be able to organize learning evenly.
Effect of attitude and motivation on turning practice
Authors: Wibowo H , Setiawan H S D , Prasetya T A , Kusnantoro M I
Published: December 2020

This research aims to determine the effect of attitudes of turning practice with students’ turning practices achievement, the influence of turning practice motivations with turning practice achievements, and the influence of turning practice attitudes and practice motivation on the turning performance of students of PIRI 1 Vocational High School. This research is a descriptive study with a quantitative approach. This study’s population was students of class XI and XII majoring in machining engineering at PIRI 1 Vocational High School. Data collection techniques using questionnaires and documentation. Data analysis techniques using descriptive analysis and regression analysis. Based on the research results, the attitude of practice has a positive and significant effect on turning practice with a contribution of 37%. The motivation of practice has a positive and significant effect on the achievement of turning practice with a contribution of 30%. The attitude of practice and practice motivation positively and significantly affects practice achievement with a contribution of 41%, and the regression equation Y = 46,141 + 0,365.X1 + 0,183.X2.
Evaluation of shielded metal arc welding learning in vocational high school
Authors: Munadi S , Syauqi K , Feriyanto M I , Lutfian F
Published: December 2020

This study aims to determine the level of planning, implementation, and assessment of learning outcomes in the XI class of shielded metal arc welding (SMAW) techniques at the state vocational high school 1 Sedayu, Bantul Regency. This type of research is a descriptive study with a survey method. Data collection using a questionnaire. The study population was 90 students of class XI state vocational high school 1 Sedayu. The sample was taken the same as the population. Data collection using a questionnaire. The data analysis technique used a quantitative descriptive analysis. Based on the data analysis results, the planning category is medium, with a mean of 29.48. The implementation is a very high category with a mean of 49.60, the assessment of learning outcomes categorized as high with a mean of 10.68. The results showed that the evaluation SMAW technical learning was in the high category. Results also showed that the level of evaluation of the SMAW technique learning on planning is in the medium category and the evaluation of the implementation of the SMAW technique learning was in the very high category.
The effect of twist drill angle and spindle speed on surface roughness in S45C steel drilling process
Authors: Saputro R D A , Sukardi T , Wibowo Y E , Hardiyanta R A P
Published: December 2020

The purpose of this research is to determine the effect of twist drill angle variations and spindle rotational speed on the surface roughness of S45C steel in the drilling process. The method used in this research is the experimental method. The independent variables used in this study are variations in twist drill angle (118°, 122°, 125°) and spindle rotational speed variations (1036 rpm, 1340 rpm, 1630 rpm). The dependent variable used is the result of surface roughness in S45C steel. While the control variable used is a feed rate of 0.18 mm/round. The results showed the highest surface roughness was obtained at 125° twist drill angle variation and spindle rotational speed of 1630 rpm with a roughness value of 8.590 µm, while the lowest surface roughness value was obtained at 118° twist drill angle variation and spindle rotational speed of 1036 rpm with a roughness value of 2.898 µm. This research can be developed to find standards from other aspects that affect the results of the drilling process.
Model of university-industry collaboration to support internship program in Engineering Faculty of Universitas Negeri Yogyakarta
Authors: Sudiyatno S , Nuryanto A , Sutopo S , Nashir I M
Published: December 2020

Collaboration between industry and universities is well recognized by scholars and policy makers as a necessity for industrial innovation products and university graduate skills development. This study presents a proposed university-industry collaboration model which expresses the university and industry benefits obtained through the collaboration experiences. Method used to explore the model of collaboration that will be proposed is observation to industries where students doing internship and FGD. The result shows that activities of collaboration are very potential to bring benefits to both parties. The proposed UIC model is suited for use at two different courses, those are internship program and final project course. The model is also implemented to assist in realizing the third role of universities in community service in the area of the contribution to innovation and R & D, production commercialization and technology transfer.
Modeling of Hydraulic ABS Plant and its Control By Using fuzzy Mamdani with adaptive slip Frequency to improve stopping distance and steering ability
Authors: Sumarli  , Harly Muchammad , Marji
Published: December 2020

Many antilock btrake system ABS (what is ABS?) plant dynamics were designed and developed by researcher, it is mostly in quarter car model. Plant could be ABS with hydraulic, air or electromagnetic energy transfer of braking processes. Kind of ABS controller method were also developed and proposed to achieve the desired control response such as, stopping distance and steering ability under circumstance non-linear braking dynamics and uncertainty road surface-wheel. There is no-intelligent and artificial control event hybrid of both. PID, Observer, sliding mode, LQR, Fuzzy and Neural network are commonly used to control ABS plant. This research method proposed ABS hydraulic plant design, which controlled by Fuzzy to control slip frequency within three sample of road surface namely snow, sand and asphalt surface road. For slip control reference variable are setup in varied value to approach the optimal sopping distance. Result of simulation shown that slip of 2,35 has a superior of stopping distance control, means the shortest stopping distance compared with another setting value.
Project-based learning model with real object in vocational school learning
Authors: Arifin Handoyono Nurcholish , Suparmin  , Samidjo  , Bintoro Johan Arif , Suyitno
Published: December 2020

Learning in vocational schools is not enough just teacher-centered because the material presented does not only cover cognitive aspects, but also the affective and psychomotor aspects. In fact, there are still many teachers who use conventional modes, including learning technical drawings, so that student learning outcomes are low. The purpose of this research was to determine the learning outcomes of the PjBL model using real object media better than conventional methods in technical drawing subjects. A quasi-experiment was used in research with a nonequivalent control group design. The study population was 42 students of class X TP. The sampling technique uses cluster sampling. Class X TP1 as a control class with 23 students and Class X TP2 as an experimental class with 19 students. Data collection techniques using test techniques. The research instrument was a test sheet. The data analysis used t-test analysis with prerequisite tests, namely the normality test and homogeneity test. Based on testing the hypothesis test, it was concluded that the PjBL model with real objects gives better learning outcomes compared to conventional methods of learning outcomes of technical drawings.
Robust parameter design of shielded metal arc welding (smaw) for optimum tensile strength
Authors: Setiawan M.D.I. , Pradana Y.R.A. , Suprayitno
Published: December 2020

Shielded Metal Arc Welding (SMAW), an arc welding process that uses a consumable electrode consisting of a filler metal rod coated with chemicals that provide flux and shielding, is widely used in engineering applications. SMAW parameters that usually applied in practice is still possible to be optimized to improve the process to become robust. This work is focus on an optimization of SMAW process on ASTM A500 Hollow Square Pipe, as it is widely found in applications. The welding parameters such as welding current, electrode angle, root gap, and electrode type are adopted as process parameters. Taguchi robust optimization is applied as optimization strategy, and L9 fractional orthogonal array is selected as design of experiment. The optimization objective is to maximize tensile strength of SMAW welded joint. The optimization results found that welding current 100A, electrode angle 90o, root gap 2 mm, and electrode type E7018 of SMAW parameters give the optimum tensile strength. The tensile strength gain of robust design based on the initial design was carried out by 98,39 MPa (from 259,45 MPa of initial design to 357,84 MPa of optimum design).
The Effect of CVT Rollers Weight on Power and Torque of Honda Vario 125 Engine in Garuda Hybrid Car 2017
Authors: Arta I W Y , Arifin Z , Yudantoko A
Published: December 2020

This study aims to find out the impact of CVT roller’s weight variable to “Honda Vario” 125 engine power and its torque in “Garuda Hybrid 2017 car”. This paper is a kind of experimental research. The object of this paper is the “Honda Vario” 125 engine that has been bored down to 120cc in “Garuda Hybrid 2017 car”. There are 5 different types of calibration samples. The calibration uses a dyno test to test the engine. After calibrating the engine, the research uses descriptive analysis as the analysis data technique. The results show that: (1) the change of CVT “Honda Vario” 125 weight variable roller influence the power produced by the engine; the bigger the roller weight, the bigger the power produced by the engine. (2) The influence of its weight variable also influences the torque of the engine; the lighter the roller weight, the bigger the torque of the engine.
The Effect of Tire Pressure to Fuel Consumption of G19 Garuda Urban Cars
Authors: Arifin Z , Yoga I N
Published: December 2020

The purpose of this study was to determine the effect of tire pressure on fuel consumption for Garuda Urban Gasoline G19 in the Shell eco-marathon Asia, 2019. This research is a type of experimental research using FDR tires on the UG19. The research was conducted by applying the tire air pressure 50 Psi, 75 Psi, 80 Psi, and 90 Psi in each pressure test, the calculation of fuel consumption is carried out to determine the effect of energy consumption in each test of each pressure. The data analysis method was carried out by using descriptive analysis. The results showed that: By applying FDR tire pressure for UG19 cars with a pressure of 90 Psi, the fuel consumption reached 5.1 ml with the calculation of the achievement of energy consumption of 395 km / l. With the test results, it shows that giving an increase in tire pressure will greatly affect fuel consumption and energy consumption achievement.
Efforts to improve chassis system learning through learning media anti-lock brake system (abs) integrated hardware-in-the-loop (hil)
Authors: Nauri I.M. , Ihwanudin M. , Ismail H. , Mindarta E.K. , Harly M. , Sumarli Putra A.B. , Awanggapati B.
Published: December 2020

The chassis system directs students to understand the basic concepts of modern motor vehicle maintenance and repair. One of the subjects is the anti-lock brake system (ABS) which can cause misconceptions in learners. So it takes learning media that can improve understanding and learning results,namely learning media anti-lock brake system (ABS) integrated hardware-in-the-loop (HIL). The implementation of ABS-HIL aims to improve student learning outcomes. Before application, the development of learning media is carried out. Sample of 27 students, with observation & pre-test & post-test data collection techniques. The data is analyzed descriptively and tests “t”. The results of the study found an improvement in the results of the study proven post-test scores = 90,44 more than the pre-test score = 78,44.
SU(1, 1) covariant s-parametrized maps
Authors: Klimov Andrei B , Seyfarth Ulrich , de Guise Hubert , Sánchez-Soto Luis L
Published: December 2020

We propose a practical recipe to compute the s-parametrized maps for systems with SU(1, 1) symmetry using a connection between the Q- and P-symbols through the action of an operator invariant under the group. This establishes equivalence relations between s-parametrized SU(1, 1)-covariant maps. The particular case of the self-dual (Wigner) phase-space functions, defined on the upper sheet of the two-sheet hyperboloid (or, equivalently, inside the Poincaré disc) are analysed.
Unsteady processes in a centrifugal compressor: from a physical experiment to a virtual stand
Authors: Lebedev A , Kozhukhov Y , Ivanov V , Kartashov S , Nguyen M H , Lebedeva S , Lopulalan Kh , Aksenov A
Published: December 2020

Virtual testing unit description for unsteady flow phenomena investigations in a centrifugal compressor based on ANSYS 12.0 system is presented. Comparisons of calculated and experimental results for steady and unsteady data are acceptable. Transient Blade Row methods (the CFX Transient Blade Row Modeling with the terminology of Turbo component) - is the sector of blades in a given blade row that are being modeled in the analysis. Transient Rotor-stator analyses involve at least two components, one rotating and one stationary component.
Non-stationary processes in a centrifugal compressor: from experiment to practice
Authors: Lebedev A , Lebedeva S , Kozhukhov Y , Kartashov S , Ivanov V , Yanin I , Hai N M
Published: December 2020

The article deals with the problems of diagnostics of surging phenomena in centrifugal compressors. The reasons for the surge phenomenon and the method for its diagnosis to prevent emergencies are stated. The article describes the phenomenon of rotating stall, which precedes the surge. Diagnostics of the appearance of a rotating stall opens the possibility of predicting the appearance of a surge. This allows for an efficient and safe surge protection system. Solving the problem of developing new principles for constructing surge diagnostics systems. Application of biorthogonal wavelet transform for prebreak detection.
Fluid - structure interaction analyze for the centrifugal compressor 3d impellers
Authors: Danilishin A , Petrov A , Kozhukhov Y , Kartashov S , Ivanov V , Zuev A
Published: December 2020

The article deals with the issues of the 3D impellers strength analysis for the different centrifugal compressors. Two air compressors are considered, the first for General industrial use, the second for turbocharging the internal combustion engine. The third compressor is designed for the turboexpander unit that operating at high pressure medium. The materials of the impellers were steel, titanium and aluminum alloys. The expediency of using the Fluid-Structure Interaction approach for the strength analysis is considered for these compressors. With the FSI approach, a coupled CFD-FEA solution is performed. Gas-dynamic forces from the medium pressure are taken into account in the impeller strength or vibration analysis. The Ansys package is selected as the program for analysis. CFD models are built and configured in the Ansys CFX. The FEA solution carried out in the Ansys Static structural. The results of strength analysis are compared with and without pressure forces for all impellers. As a result, there were no significant differences in the two solutions for the air compressors. However, for high-pressure compressors, the results of the coupled solution showed the need to take into account the CFD solution. Based on the obtained data, a graph of the reliability coefficient dependence on the increase in the suction pressure in the range from 1 to 100 bar is plotted.
Investigation of the elemental composition of the WNF-95 sintered powder alloy obtained by the electroerosive dispersion of waste in a carbon-containing liquid
Authors: Ageev E , Ageeva E , Khoryakova N
Published: December 2020

The results of the study of the pressed and sintered electroerosive powder alloy WNF -95 are presented. Powder alloy WNF-95 was obtained by electrodispersion of shavings from waste tungsten- nickel-iron alloy in kerosene. Sintering of electroerosive powder alloy WNF-95 was carried out by the method of spark plasma sintering. The aim of this work was to study the elemental composition of the WNF-95 sintered powder alloy obtained by electrodispersion of waste in kerosene. It has been established that the elemental composition of the sintered sample obtained by sintering the electroerosive pseudo-alloy WNF-95 is comparable to the elemental composition of the initial powder, which indicates the efficiency of its use for the manufacture of tungsten-nickel-iron alloys.
Increasing the efficiency of the working process of a forest fire ground-sweeping machine with an energy-saving hydraulic drive of the throwing rotor
Authors: Popikov P I , Gnusov M A , Popikov V P , Sharov A V
Published: December 2020

The article deals with the problem of creating machines and units for the prevention and suppression of forest ground fire. The purpose of the study is to increase the efficiency of the working process of the soil-throwing machine by substantiating the parameters of the energy-saving hydraulic drive of the rotor-thrower. The rational values of the pre-charging pressure and the working volume of the pneumohydraulic accumulator have been established, which ensure the reduction to a minimum of the number of operation of the safety valves when the rotor-thrower meets obstacles. The optimum charging pressure of the pneumohydraulic accumulator is 6 … 7 MPa, the working volume is 5 … 8 dm3, while the energy-saving hydraulic drive stores energy of about 15 … 17 kJ during the working cycle, pressure surges do not exceed 13.3 MPa, and the recovered energy at density of obstacles up to 200 pcs / km due to the reduction in the number of operation of safety valves can be about 3000 kJ per 1 km of strip laying. The productivity of the forest fire ground-throwing machine with a new energy- saving hydraulic drive increases by 16-22% while reducing energy consumption by 7-8%.
Method for determining malfunctions of hydraulic drives of high-speed equipment
Authors: Kobzev K , Vyalov S , Rybak A
Published: December 2020

The article discusses the control system of a hydraulic power source of constant pressure, which is a pump-storage power source, equipped with the original design of the automatic unloading of the hydraulic pump, which provides relay switching of its operation mode. A mathematical model is proposed, obtained using a modeling technique based on the application of the theory of volumetric rigidity of hydraulic systems and their elements. The results of a numerical experiment carried out by numerically solving the equations that make up the mathematical model of a power source are also presented. As a result of a numerical experiment, the main technical capabilities of the considered power source and the influence of its main structural parameters and functional features of the system on operational properties are revealed.
Modification of the quantum grover algorithm by using the inversion method around the middle
Authors: Cherckesova L , Safaryan O , Pilipenko I , Porksheyan V , Bogdanova N , Beryoza N
Published: December 2020

The article proposes a modification of Grover’s quantum oracle quantum search algorithm, which makes it easier to search the database. The algorithm is implemented in the Python programming language using the Reggeti Forest cloud quantum service. The authors of the article use the mean flipping method, which solves the search problem during the iterative order √ (2 ^ n). Development offers great potential for the practical application of the Grover quantum algorithm, as it is characterized by higher performance and speed when performing research. Theoretically, the algorithm provides quadratic acceleration compared to conventional computers. It is not an exponential acceleration, but it remains important for large data carriers. The quantum parallelism of the Grover search algorithm is based on a simultaneous change in the amplitudes of all the inputs. This is done through a superposition of states, which is a purely quantum concept. In addition, the research is carried out globally, which indicates a significant improvement in optimization procedures. Grover’s algorithm, on the other hand, is sensitive to the number of iterations. The more iterations, the smaller the amplitude of the correct answer, so the wrong choice of this parameter can digest the solution. In addition, the operation of the algorithm is limited in the case of the introduction of noise into a quantum system, which is real in modern quantum computers.
Methods of cryptographically steady elliptic curves generation
Authors: Cherckesova L , Safaryan O , Razumov P , Akishin B , Chumakov V , Smirnov I , Trubchik I
Published: December 2020

This article is devoted to a complex study of elliptic curves and description and characteristics of it are presented. Moreover, algorithms for generating cryptographically stable elliptic properties that ensure the greatest curves are revealed. The detailed description is given, and the resistance of the elliptic curves to the different types of cryptographic attacks are determined, grounding on the comparative analysis of information security system.
Fuzzy topology and fuzzy geometry of the topological concepts
Authors: Gadjiev Djavanshir , Rustanov Aligadzhi
Published: December 2020

The typical approach to analyze the images in terms of recognition and further interpretation is to obtain an extension of the conventional geometry to the fuzzy case. The fuzzy geometry, which consists of the topological and geometrical structures such as connectedness, adjacency, principle of surrounded-ness (areas seen as surrounded by other areas are perceived as figures), convexity, area, perimeter, height, width, adjacency and etc. are essential to reflect the geometrical ambiguity of an image processing. Moreover, the application of the fuzzy geometry properties is important in soft computing decisions to further analyze and interpret a fuzzy image. The properties of fuzzy geometry based on the concepts of the length, breadth, height and methods of measuring a distance between fuzzy numbers are introduced here due to the numerous of applications in engineering problems and other fields.
Prediction of parameters of building structures using regression equations with independent action of variables and constancy of operating factors
Authors: Korolkov D , Karmokova K , Tuchkina L
Published: December 2020

In this article, the authors present a method for predicting the parameters of building structures and calculating the residual life using regression equations. The most commonly used regression equations were used: linear, polynomial, power, exponential, exponential, logarithmic, semilogarithmic, hyperbolic and logistic. The authors proposed to use one-factor regression equations, in which the variable is time, and the dependent value is the parameter of the building structure, the changes of which the researcher needs to determine. These equations are named by the author as the basic regression equations. Also, the authors in this article in the future, the basic equations are presented as multifactorial. This is achieved by replacing the coefficients of the main equation with regression equations, which are obtained after a series of tests are performed for various values of the selected input parameters (environmental conditions, material of construction, etc.), regression equations are obtained for each such state, as a result of which there are a number of values for the parameters of the basic regression equations. As a result, a repeated regression analysis is carried out and a regression equation is constructed for the coefficients of the main regression equation, which depends on the value of the specified parameters. Such equations are called secondary by the authors. Examples are given for conditional linear regression, where the author has demonstrated how the coefficients of the main regression equation are replaced and what final form the equation goes to after replacing the coefficients with secondary equations.
Analysis of hydraulic resistance in a rotating junction of the cooling system of an active phased array antenna of a circular view
Authors: Rybak A T , Tsybry I K , Shileev K V , Ermolenko I M
Published: December 2020

A hydraulic rotating transition is used to ensure the supply of coolant to the fuel elements when the antenna system is fully rotated. One of the main actuators of the antenna liquid cooling system is the hydraulic rotating transition. The SolidWorks Flow Simulation software package simulates the change in hydraulic resistance in a hydraulic rotating transition in various modes of operation. The process of transferring the coolant through a hydraulic rotating transition to the antenna, with full rotation, taking into account the influence of the geometric shape of the channels on the fluid flow, was modeled. The maximum values of resistances are analyzed in different operating modes. The dependence of hydraulic resistance on the quality of surface treatment of parts is given. The value of the hydraulic resistance in different modes of operation of the hydraulic rotating transition (HRT) is less than the value allowed to ensure the circulation of the working fluid in the cooling system. Based on the data obtained, an assessment of the feasibility of using the design of a hydraulic rotating transition for an active phased antenna array of a circular view at the design stage is made.
Thermomechanical damage to rolling stock wheels
Authors: Demyanov A , Demyanov A , Pavlova I , Gaylomazova E
Published: December 2020

Marshalling yards are a key part of the transportation process. Their precise operation determines the efficiency and safety of the transportation process, which, other things being equal, depend on the durability and safety of cars in real conditions, including during sorting processes on slides. Currently, during the dissolution of trains on low-power slides, shoe braking is used. This is cost-effective, but provokes the formation of thermomechanical damage on the surface of the wheels. These damages are called one-way sliders. The formation of sliders leads to downtime of cars during repairs and to the cost of restoring or manufacturing new wheels. The article presents a study of the effect of wheel sliding on the rail on the nature of thermal and mechanical damage to the wheels of rolling stock.
RETRACTED: Influence of imbalance of balancing of crankshafts during engine repair
Authors: Kokieva G , Moshkin N , Druzynova V , Radnayev D , Khiterkheyeva N
Published: December 2020

Currently, tractors and other complex machines repaired at advanced repair enterprises perform worse than new ones and have a shorter overhaul life. Let us consider what losses in the quality of the car are not replenished even with a well-organized repair in compliance with the existing technical conditions and whether they are really recoverable. If during the repair the car was assembled entirely from new good-quality parts and the required technical conditions were observed during the assembly, then no loss of serviceability of the machine during repair could take place. This means that it is difficult to eliminate the losses associated with the use during repair, firstly, partially worn out (with acceptable wear and tear) and, secondly, restored parts. The experience of using agricultural machinery shows that by using maintenance and repair tools that do not require large investments, it is possible to significantly reduce the downtime of the machine and tractor fleet. With the introduction of new, more progressive technological processes into technology, an increase in the speed and power of technology, as well as with the tasks of automatic regulation and control of machines, machine designs have radically changed. along with the mechanical ones, the machines include hydraulic, pneumatic, electrical, electronic devices. The imbalance in the correction planes of the crankshafts assembled with a flywheel and clutch supplied to spare parts is 1.2-6.5 times and 1.3-10.7 times, respectively, higher than the allowable one. after grinding the main and connecting rod journals for repair dimensions, the imbalance of these assembly units is also 1.5-7.2 and 1.7-12.3 times greater than the permissible unbalance of the crankshafts and to develop recommendations for improving the balancing accuracy during engine repair.
Problems and prospects of mechanical engineering innovative development in conditions of the digital economy
Authors: Shvydenko N V , Odintsova N P , Medyuha E V
Published: December 2020

The article identifies the main problems and trends in mechanical engineering in order to increase the competitiveness of its products by innovative type, discloses the nature of modern discussions on the enterprises’ technical development methods in the digital economy, proposes the strategic directions for industrial innovative development, which contribute to improving management efficiency of the machine-building complex.
Construction and testing of the parametric criterion of chemical damage of the employee
Authors: Esipov Yu V , Bochkova E A , Mamatchenko N S
Published: December 2020

This article examines the process of the chemical used in the painting of boiler housings and heaters. The effect on acetone is considered. A statistical assessment of parametric criteria was carried out, taking into account the consequences of its impact on the human body.
Structuring information on the state of labor safety at mechanical engineering enterprises
Authors: Solod S A , Novikov V V , Chukarin A N , Litvinov A E
Published: December 2020

The article discusses the issues of structuring the information received on the state of labor safety issues at mechanical engineering enterprises. Factors, multipliers and indicators on occupational safety issues at these enterprises are selected. The parameters of the BT control system and the relationship between them are determined. Sanitary and hygienic factors.
Water content of seedlings of Russian rice varieties
Authors: Goncharova Y , Bragina O , Goncharov S , Kharitonov E
Published: December 2020

Increasing price of irrigation water reduces efficiency of rice production and increases interest in developing drought-tolerant varieties of rice. The varieties adapted to stress are characterized by: maintenance of water content, high dry matter content, reduced leaf area, stability of growth and synthetic processes, as well as a high content of pigments. It was found that the high water content of plant tissues under conditions of water stress indicates an increased ability of plant different species to adapt to changing water supply conditions and provide its higher drought resistance. According to the literature, the ratio of bound and free forms of water can also be an indicator of plant resistance to drought, since the bound form of water provides the cell’s water retention capacity. In this regard, the purpose of the work is to show the possibility of differentiating domestic specimens according to the characteristic in the initial phases of development, revealing the range of variation and sources for further breeding work to create varieties adapted to drought.
Justification of production indicators of organic fertilizer based on sapropel
Authors: Morozov V , Savelyeva L , Nesterova E
Published: December 2020

The problem facing agricultural scientists is the search for effective ways to develop sapropel for fertilization to increase crop production by increasing soil fertility. One of the most important reserves of organic raw materials are the reserves of lake sapropels. It has been established that sapropel deposits, depending on the depth, have different values of agrochemical and physical properties. Having processed the empirical values of the sapropel characteristics in accordance with the requirements of the technological parameters, we obtained the optimal depths of the layer for industrial development. Its efficiency can be increased when applied together with lower doses of mineral fertilizers. To improve the technological process for the production of sapropel fertilizers, it is necessary to take into account that sapropel should be extracted from a scientifically substantiated layer of the deposit and in its natural state sapropel is not a full-fledged fertilizer; its effectiveness can be increased because of application together with mineral fertilizers. Mixing is one of the most important operations in fertilizer production technology and for this purpose; it is advisable to use a drum mixer.
Types of bale loaders and their comparative performance
Authors: Orlyansky A , Orlyanskaya I , Petetnev A , Kulaev E , Bobryshov A
Published: December 2020

The article provides an overview of different types of technical means for loading bales of silage. Using the program for simulation of the forage harvesting process, computer calculations were made of the comparative efficiency of the operation of loaders of rolls of various types at a rate of haylage harvesting from 100 to 650 tons per shift (10 hours). It has been established that, according to the criterion of unit total costs at a low rate of haylage harvesting - from 100 to 300 tons per shift - loading units with a front loader mounted on a tractor are more efficient. At a higher rate of forage harvesting, it is more efficient to use self-propelled loaders. With an equal unit total cost of funds, self-propelled loaders provide 1.5-2.0 times less labor costs.
Key end-to-end digital technologies in the ecosystem of the state’s digital economy
Authors: Kalyazina S , Iliashenko V , Kozhukhov Y , Zotova E
Published: December 2020

The state is an active participant and an important stakeholder in the digital economy development program. The expected formation of the ecosystem of the digital economy will increase the efficiency of state functions performance, increase the degree of citizens’ involvement in the life of society, and increase the competitiveness of the whole state. The effective implementation of government functions requires the fulfillment of the basic requirements for digital technologies in terms of the most effective implementation of the tasks. Based on these requirements, it is possible to identify the corresponding key end-to-end digital technologies, the inclusion of which in business processes will give maximum development.