bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and biological evaluation of roseofungin and its cyclodextrin inclusion complexes
Authors:   Kazakh University of Technology and Business, Nur-Sultan, Kazakhstan, Jalmakhanbetova R.I. , Suleimen Ye.M. ,   Sh. Ualikhanov Kokshetau University, Kokshetau, Kazakhstan,   Republican collection of microorganisms, Nur-Sultan, Kazakhstan, Eissa I.H. ,   PharmaceuticalMedicinal Chemistry Department, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt, Metwaly A.M. ,   Pharmacognosy Department, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt, Iskakova Zh.B. ,   Kazakh University of Technology and Business, Nur-Sultan, Kazakhstan, Balpanov D.S. ,   "Biolife" Ltd, Stepnogorsk, Kazakhstan, Sissengaliyeva G.G. ,   L.N. Gumilyov Eurasian National University, Nur-Sultan, Kazakhstan, Khannanov R.A. ,   "Biolife" Ltd, Stepnogorsk, Kazakhstan, Seilkhanov T.M. ,   Sh. Ualikhanov Kokshetau University, Kokshetau, Kazakhstan
Published: January 2021

Roseofungin belongs to polyene antibiotics which is more active and less toxic comparing other polyenes of this group. Roseofungin was isolated from Actinomyces roseoflavus var. Roseofungini using different chro-matographic techniques and for the first time, the complexation of roseofungin with α-, β- and γ-cyclodextrin derivatives was performed. The binding patterns of the resulted complexes were studied in silico using mo-lecular docking techniques. The best binding mode was for roseofungin against γ-CD with an affinity value of ˗42.98 kcal/mol. The proposed binding mode of roseofungin against α-CD showed unusual interaction with an affinity value of ˗41.80 kcal/mol. Also, roseofungin bonded to β-CD with a binding affinity value of ˗35.03 kcal/mol. The antiradical and cytotoxic activities of roseofungin and its obtained α-, β- and γ-cyclo-dextrin complexes were determined. The antiradical activity was performed using butylhydroxyanisole as a reference, while the cytotoxic activity was determined using Artemia salina crustaceans. As a result of the biological activity study, it was found that roseofungin and some of its complexes have weak antiradical activities.
Methods of analysis of glycoluril and its derivatives
Authors:   Institute for Problems of Chemical and Energetic Technologies SB RAS, Biysk, Russia, Bakibaev A.A. , Malkov V.S. ,   National Research Tomsk State University, Tomsk, Russia, Kurgachev D.A. ,   Institute for Problems of Chemical and Energetic Technologies SB RAS, Biysk, Russia, Kotelnikov O.A. ,   National Research Tomsk State University, Tomsk, Russia
Published: January 2021

The present work provides the literature data generalization concerning analysis of glycoluril, its derivatives and related compounds that allows obtaining information about the structure and properties of these com-pounds. Basic methods for analysis of glycoluril and substances on the basis thereof are considered, ad-vantages and disadvantages of these methods are described. The generalized results of the methods of analy-sis of glycoluril and its derivatives show that the majority of carried studies are focused on the revealing of purity and identification of related impurities for compounds that found practical application (drugs, mono-mers and polymers on the basis thereof). Consistent trend to active search of new methods to analyze macrocyclic and supramolecular systems synthesized on the basis of glycoluril is observed. The aim of the present review is to take attention of chemists to the most advanced methods of analysis of glycoluril and its derivatives with reference to promotion of further research. The literature analysis will be useful for research-ers dealing with designing of new molecules based on glycoluril with given properties where the methods of process control and analysis of target compounds has a decisive importance.
Biologically active substances from Achillea nobilis L.
Authors:   JSC ", Kishkentayeva А.S. ,   International Research and Production Holding ",   Phytochemistry",   , Karaganda, Kazakhstan, Mantler S.N. ,   JSC "International Research and Production Holding "Phytochemistry", Karaganda, Kazakhstan, Zhakanov М.М. ,   JSC "International Research and Production Holding "Phytochemistry", Karaganda, Kazakhstan, Adekenov S.М. ,   JSC "International Research and Production Holding "Phytochemistry", Karaganda, Kazakhstan
Published: January 2021

The review summarizes data on biologically active compounds of Achillea nobilis L. and methods of their isolation. From Achillea nobilis L., collected in different places of growth, the following have been isolated: essential oil, the main components of which are monoterpene compounds; sesquiterpene lactones estafiatin, hanphyllin, anobin, chrysartemine A, canin, anolide and tanapartin-β-peroxide; the steroid acetyleucanbin; flavonoids: 3,5-dihydroxy-6,7,8-trimethoxyflavone, 5-hydroxy-3,6,7,4’-tetramethoxyflavone and 5,3’-di-hydroxy-3,6,7,4’-tetramethoxyflavone. It has been determined that the component composition of the essen-tial oil of Achillea nobilis L. largely depends on the soil and climatic factors in the places of its growth, the phase of the growing season and the method of its extraction from plant raw materials, and the extractant used (chloroform, ethanol, hot water, diethyl ether). Antibacterial, antimicrobial, antioxidant, antiparasitic activi-ties are characteristic both for the sums of extractive substances from Achillea nobilis L. and for individual compounds isolated from them. Methods for the isolation of biologically active substances from Achillea nobilis L. for the development of new drug substances are described. The main aim of this work was a com-parative analysis of the available research results on the phytochemical study of Achillea nobilis L.
Study of the biologically active acyclic ureas by nuclear magnetic resonance
Authors:   National Research Tomsk State University, Тоmsk, Russia, Bakibaev А.А. , Sadvakassova М.Zh. ,   L.N. Gumilyov Eurasian National University, Nur-Sultan, Kazakhstan, Malkov V.S. ,   National Research Tomsk State University, Тоmsk, Russia, Еrkasov R.Sh. ,   L.N. Gumilyov Eurasian National University, Nur-Sultan, Kazakhstan, Sorvanov A.A. ,   National Research Tomsk State University, Тоmsk, Russia, Kotelnikov O.A. ,   National Research Tomsk State University, Тоmsk, Russia
Published: January 2021

A wide variety of acyclic ureas comprising alkyl, arylalkyl, acyl, and aryl functional groups are investigated by nuclear magnetic resonance spectroscopy. In general, spectral characteristics of more than 130 substances based on acyclic ureas dissolved in deuterated dimethyl sulfoxide at room temperature are studied. The re-sults obtained based on the studies of 1H and 13C NMR spectra of urea and its N-alkyl-, N-arylalkyl-, N-aryl- and 1,3-diaryl derivatives are presented, and the effect of these functional groups on the chemical shifts in carbonyl and amide moieties in acyclic urea derivatives is discussed. An introduction of any type of substitu-ent (electron-withdrawing or electron-donating) into urea molecule is stated to result in a strong upfield shift in 13C NMR spectra relatively to unsubstituted urea. A strong sensitivity of NH protons to the presence of acyl and aryl groups in nuclear magnetic resonance spectra is pointed out. In some cases, qualitative depend-encies between the chemical shifts in the NMR spectra and the structure of the studied acyclic ureas are re-vealed. A summary of the results on chemical shifts in the NMR spectra of the investigated substances allows determining the ranges of chemical shift variations of the key protons and carbon atoms in acyclic ureas. The literature describing the synthesis procedures are provided. The results obtained significantly expand the methods of reliable identification of biologically active acyclic ureas and their metabolites that makes it promising to use NMR spectroscopy both in biochemistry and in clinical practice.
The correlation between the surface-active characteristics of SAFOL 23 – alcohol – water systems and the length of the alkyl radical of the alcohol
Authors:   Perm State National Research University, Perm, Russia, Shcherban’ M.G. , Solovyev A.D. ,   Perm State National Research University, Perm, Russia, Saliakhova A.O. ,   Perm State National Research University, Perm, Russia
Published: January 2021

The effect of isobutyl and isoamyl alcohols on the surface-active characteristics of SAFOL 23 nonionic sur-factant was studied. The surface tension isotherms (STI) of an aqueous solution of surfactant and its water-alcohol compositions are obtained. The structure of mixed micelles and the values of the surfactant interac-tion factor in the micelle, based on the STIs of SAFOL 23 – alcohol – water systems, were calculated. The dependence of surface activity on the SAFOL 23: alcohol ratio passes through a maximum, which is associat-ed with the transition of alcohol from co-surfactant to co-solvent due to the increase in its quantity. The wet-ting process of high dispersed polytetrafluoroethylene (PTFE) by SAFOL 23 – alcohol – water compositions was studied, contact angle isotherms were constructed. The PTFE surface was hydrophilized by compositions at ratios which comply with surface activity maximum. SAFOL 23 is more adsorbed on the surface of the sol-id phase than on the liquid-gas interface. The appending of alcohol into an aqueous solution of surfactant changes the ratio between hydrophilic and lipophilic groups of the composition, which affects cloud point. It significantly expands the range of application of surfactants and allows the use of SAFOL 23 as a solubilizer, emulsifier and wetting agent.
Real and quasi heortonyms as intercultural contextualized and conceptualized names
Authors: Gałkowski Artur
Published: January 2021

Artykuł przedstawia onomastyczno-kognitywne studium heortonimów (nazw świąt) jakospecyficznych jednostek chrematonimicznych, które funkcjonując na zasadzie ideonimówidentyfikujących inicjatywy socjo-kulturowe, przenoszą kontekstualne i konceptualnetreści odnoszone do obiektu nominacji, tj. kodowany przez nie przekaz semantyczny.Proponowane jest ujęcie klasyfikujące heortonimy jako nazwy cyklicznych lub rzadziejokazjonalnych wydarzeń, które upamiętniają lub zwracają uwagę na kontekstualizowanąideę z kręgu kultury niematerialnej. Są to monorematyczne bądź, częściej, polirematycznepropria, służące do konceptualizacji świąt motywowanych religijnie oraz podobnie kwalifikowanychdedykacji dni w kalendarzu, inspirowanych kulturą świecką lub parareligijną.Stąd wyodrębnienie „heortonimii właściwej”, wchodzącej w zakres onimi religijnej oraz„quasi-heortonimii”, której obiekty funkcjonują w komunikacji na zasadzie asocjatywnegoprzywołania wzorowanego na formule religijnej i modelu kampanii społecznych. Analizaobydwu typów heortonimicznych ma charakter interkulturowy, przy założeniu, że zarównoheortonimy właściwe, jak i quasi-heortonimy należą jednocześnie do wielu kulturi mają potencjał przenikania do nowych kręgów kulturowych, stanowiąc, w zależnościod kontekstu, element dyskursu religijnego, ideologicznego, społecznego, ale także komercyjnegooraz kreatywno-medialnego. Wysunięte wnioski oparte są na badaniu głównieangielsko- i polskojęzycznego korpusu, pochodzącego z danych rejestrowanych w kalendarzachreligijnych oraz świeckich kultury globalnej, w przeważającej części związanejz cywilizacją zachodnią. Studium ma też wartość dodaną w postaci opinii onomastyczno--terminologicznej dotyczącej definicji i zakresu heortonimii oraz zestawienia heortonimiiwłaściwej i quasi-heortonimii z podobnie funkcjonującymi strukturami chrematonimiiideacyjnej oraz chrononimii.
Koniunkcja i zdanie z czasownikiem egzystencjalnym – o quasi-tautologicznej konstrukcji typu Są przyjaciele i przyjaciele
Authors: Żabowska Magdalena
Published: January 2021

Artykuł przedstawia opis quasi-tautologicznej konstrukcji jest (bywa) _i i _i, którego egzemplifikację stanowi zdanie Są przyjaciele i przyjaciele. W odróżnieniu od wcześniejszych prac, analiza koncentruje się na autentycznych wypowiedziach mówionych. W artykule analizuję właściwości semantyczne takich konstrukcji na tle funkcji koniunkcji i zdania egzystencjalnego. Dla tego celu wykorzystano paradygmat językoznawstwa strukturalnego jako rygorystycznego model opisu znaczenia. Artykuł prezentuje, w jaki sposób można wykorzystać do opisu analizowanej konstrukcji semantyczne funkcje koniunkcji i reiteracji. Jak wykazano, opisywana konstrukcja (i) nie konstytuuje ani zdania egzystencjalnego (quasi-ontologicznego), ani zdania uniwersalnego; (ii) jej funkcją jest kontrastowanie obiektów pojęciowych. Uzasadniam, że konsekwencją tej funkcji analizowanej konstrukcji jest ograniczony zestaw wchodzących w jej skład czasowników (por. jest, bywa), a także stała liczba iterowanych elementów (wyłącznie dwa). Ponadto operacja kontrastowania może wywoływać pragmatyczny efekt hierarchizowania składników. Na podstawie tych spostrzeżeń, ze względu na to, że wszystkie wskazane własności można sprowadzić do właściwości semantycznych koniunkcji i repetycji, uznaję tę konstrukcję za produkt językowy, a nie za leksykalną jednostkę języka.
Global productive chains and decent work management technologies
Authors: Jacques Caroline , Mueller Rodrigo Rafael
Published: January 2021

The article presents a reflection on decent work management technologies in the global productive chains. Based on economic sociology and anthropology authors, it discusses the general characteristics of the global productive chains, especially the concept of decent work as a management technology for the labor´s international regulation. The empirical focus of this research was a clothing manufacturing productive chain in the south of Santa Catarina. Interviews were carried out with social and economic actors that are part of this sector, in particular, unions and entrepreneurs. As a conclusion, it is important to highlight that decent work management technologies have the formal merit of inserting the decent work guidelines into the contracts between the suppliers and subcontractors. However, the research points out that the asymmetries in the financial negotiations which are typical of the productive chains continue to promote precarious and informal work in the sector.
Analysis of The Role of The Government and Ventural Capital On the Development of Startup in Indonesia
Authors: Yulianto Wagista
Published: January 2021

This study aims to analyze the role of the Government and Venture Capital in the development of startups in Indonesia. Research was conducted on startup companies in 2017 - 2020, analysis from the startup side comes from Qiwii.id which represents successful startups to date and failed Assistantku.com. On the other hand, analysis also comes from the Government and venture capital. The data search method uses direct interviews to data sources, then strengthened by analysis of research data from various parties such as dailysocial.id, Global Startup Genome, Techinasia.com, MIKTI, and various other parties. The research results prove that the Government does not play a direct role in the development of startups in Indonesia, but   through   the   ecosystem, marketing support and regulations. Meanwhile, the taxation aspect of startups does not really have an impact on startups, because the majority of startups do not have income above IDR 4.8 billion (not including the taxpayer category). In terms of Venture Capital, it actually plays an active role in the development of startups because the nature of venture capital which also owns startup shares makes the commitment of both parties to develop their startups high. These various conditions are consistent with the balanced scorecard review in each startup.
Elaboration of a flowchart for healthcare quality improvement of patients with diabetic foot ulcer
Authors: Santos Isabela Macedo Vitorino , Silva Tathiane Ribeiro , Antunes Douglas
Published: January 2021

Objective: The aim of this study is to map the work process of a Municipal Centre for the care of diabetic foot ulcer, in order to elaborate a multi-professional flowchart for the management of these patients. Methods: Qualitative study, developed by means of Bizagi software version 3.7.0.107, for the purpose to map the flow of activities encompassing the first attendance for people with diabetic foot ulcer, through observational record, elaborating a multi-professional flowchart for improving quality of care. Results: The investigation, mapping and comparison between two flowcharts, current and future directions, highlighted the need to offer multi-professional care for patients, besides of implementing improvements in the quality of care, emphasizing the importance of holistic approach over the  chronic wound carrier, avoiding, consequently, futures complications. Conclusion: Finally, it was elaborated a new map of work process to consolidating the presence of multi-professional team for treatment of people with diabetic foot ulcer.
Functional characterization of biofortified sweet potato flour dried at different temperatures
Authors: Gonçalves Souza Diene , Resende Osvaldo , Pilon Lucimeire , Alberto Colnago Luiz , dos Santos Garcia Rodrigo Henrique , Borges de Almeida Adrielle
Published: January 2021

Sweet potato (Ipomoea batatas (L.) Lam.) is an abundant source of carotenoids, and the processing of its tubers as flour is an alternative to add value and expand its use. The objective was to characterize flour from the pulp of biofortified sweet potato dried at different drying temperatures. Biofortified sweet potatoes (accession CNPH1210) were dried in a forced air ventilation oven, under four temperature conditions: 45, 55, 65 and 75 °C. Drying continued until the sliced roots reached moisture content of 14 % (d.b.). Fibers, phenolic compounds, carotenoids, β-carotene, antioxidant capacity by ABT and DPPH, scanning electron microscopy, high-field magnetic resonance imaging, infrared absorption spectrometry were evaluated. Flours obtained from sliced roots dried at 45, 55, 65 and 75 ºC showed stability in their morphological characteristics. The temperature of 45 °C was the most indicated for the production of biofortified sweet potato flours, as the produced flours had higher contents of bioactive compounds, being a significant source of carotenoids.
Academic Process Oriented to the Reputational Capital of Brazilian HEI Brands
Authors: Cox Kenia , De-Bortoli Robelius
Published: January 2021

The reputation of a university must be positive, whether it is private or public, given the competitiveness of its environment.  Reputation is an indicator of organizational success and can be monitored by the brand's reputational capital, which corresponds to the harmony between the characteristics established by the managers - brand identity, and the perception defined by its stakeholders - brand image. In a complementary way, business processes are useful tools for optimizing the roles and outcome of organizations. The objective of this work was to model an academic business process, to increase the efficacy of higher education training, guided by the reputational capital of the brands of universities in Brazil. A quasi-systematic review was carried out to investigate academic business processes - identity; bibliographic review to understand reputation and competitiveness – image; and was elaborated a diagram of the academic business process model with UML resources, SIPOC approach, relating identity and image through guidelines: elaboration and evaluation of student work individual plan, student self-efficacy stimulus, individual teaching advice, positive university culture, interaction with society and co-creation of brands by students from Brazilian HEIs - reputational capital.
Trajectory Simulation Approach for Autonomous Vehicles Path Planning using Deep Reinforcement Learning
Authors: De Oliveira Lima Jean Phelipe , Oliveira Raimundo Correa de , Costa Cleinaldo de Almeida
Published: January 2021

Autonomous vehicle path planning aims to allow safe and rapid movement in an environment without human interference. Recently, Reinforcement Learning methods have been used to solve this problem and have achieved satisfactory results. This work presents the use of Deep Reinforcement Learning for the task of path planning for autonomous vehicles through trajectory simulation, to define routes that offer greater safety (without collisions) and less distance for the displacement between two points. A method for creating simulation environments was developed to analyze the performance of the proposed models in different difficult degrees of circumstances. The decision-making strategy implemented was based on the use of Artificial Neural Networks of the Multilayer Perceptron type with parameters and hyperparameters determined from a grid search. The models were evaluated for their reward charts resulting from their learning process. Such evaluation occurred in two phases: isolated evaluation, in which the models were inserted into the environment without prior knowledge; and incremental evaluation, in which models were inserted in unknown environments with previous intelligence accumulated in other conditions. The results obtained are competitive with state-of-the-art works and highlight the adaptive characteristic of the models presented, which, when inserted with prior knowledge in environments, can reduce the convergence time by up to 89.47% when compared to related works.
Issues on the optimization of bioreactors of microalgae and cyanobacteria crops for hydrogen and bioproduct productions
Authors: Montano Carlos Julio , Seger Pereira Mercedes Sonia , PR Campos Tarcisio
Published: January 2021

Optimizing the design and operating parameters for optimum production of hydrogen and other bioproducts is a necessary step to address the rate of production of this energy input. Optimization is basically based on the appropriate choice of microalgae strain along with the available growth conditions. This paper presents a simplified review of the possible monitoring variables for microalgae and cyanobacteria crops. In addition, the design of open pond bioreactors and photobioreactors (PBR) that allow greater control of monitoring and crop parameters were presented. The physicochemical bioproduct characterization, such as fatty acids constituent and gases, is an aspect to be considered. The use of the optimization of the physical-chemical properties for their subsequent processing may improve the production of biofuels and biomass. In addition, the generation of hydrogen in the photosynthetic cycle of bioreactors based on microalgae cultures is presented as a solution to energy demand. And finally, we comment on some findings obtained from Multiphysics computational modeling carried out in PBRs.
Innovative Capacity of Incubated Companies in Brazilian Technology-Based Business Incubators
Authors: Maria da Rocha Caixeta Ádria , Henrique Stoppa Marcelo
Published: January 2021

TBCs are ventures formed by entrepreneurs whose core is technical knowledge and which are sometimes accompanied by business incubators. It is estimated that the earnings of TBCs incubated in Brazil are more than R$550 million and that they generate around 14 thousand jobs. Thus, given the importance of TBCs for a country's social and economic development, this research is justified, which aims to measure the innovative capacity of TBCs linked to incubators of Brazilian technology-based companies. The chosen methodology was descriptive research, of quantitative nature, whose data collection technique uses the Innovation Radar questionnaire. The sample of this study had the participation of 62 incubated in the incubation stage in 22 incubators located in the states of Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, and Distrito Federal. Among other results, the study showed that, in a sectorial analysis, mining companies in the service sector are not very innovative and the other occasional innovators, as well as that the industries of Mato Grosso do Sul are not very innovative and the other occasional innovators. Finally, in comparison, all TBCs that participated in the research are occasional innovators, that is, in general, the entire sample was characterized as an occasional innovator.
Manufacture of a non-woven using bamboo cellulose base (angustifolia) as a filter medium for the manufacture of masks
Authors: Esparza Encalada Willam Ricardo , Herrera Wilson , Chamorro Luís
Published: January 2021

The purpose of this study was to produce a non-woven, using a base of bamboo cellulose (angustifolia) with a particle size of 1mm, and it begins with the weighing of 100 g bamboo cellulose, which is mixed with a bath ratio bamboo / water 1:10 in a mixer grinder, placing 1 liter of water mixes and forms a viscous solution, this solution is placed on a frame stretched with polyester woven mesh and another frame without mesh, once the layer is formed, it is remove the upper frame without mesh and compress it manually with a sponge, removing excess water and drying in the room at a temperature of 20 0C for 8 hours, evaporated the moisture from the bamboo cellulose (angustifolia) and dried, separated from the frame and a laminated nonwoven (filter) was obtained. Finding that the breaking strength and its elongation in thickness of 0.3mm is 2.73 N and 0.895 mm respectively and thickness of 5mm is 31.2 N and 1.01 mm. The resistance and extension is very low in the two cases, and there are no statistically significant differences between their sample medians (p> 0.05). It can be concluded that when using bamboo cellulose base with a particle size of 1mm, and forming the non-woven with thickness of 0.5mm and 3mm, it has low resistance and extension, finding that if the raw material has an influence on the conformation of the non-woven.
Relationships of Body Image and Eating Attitudes with Sociodemographic, Psychologic and Nutritional Factors in University Students Attending First Classes
Authors: Wheat Janette , Hawley Miles , Jones Bridgette , Kelsey Kelsie , Thompson Jatoya , Thompson Demetrius
Published: January 2021

Senior Seminar students for their research project investigated, “Perceptions of college students on the effects of body image in today’s society.” In this study, student researchers focused on the way body image was exemplified amongst college students from five factors: 1) their mental development, 2) realistic fashion sense, 3) athletics, 4) nutrition, and 5) the physical wear and tear of its image. The study consisted of 100 individuals on the campus of The University of Arkansas at Pine Bluff who had given time and knowledge to the situation. Through a series of analyses on the surveys administered as well as a graphing, student researchers were able to connect the survey with their general assumptions and theories on the perspectives of body image. While researching, key concepts were identified which provided a better clarification of perspectives on the body’s image. Students who experienced the judgment of their body’s image were prone to being affected in each of the five brackets mentioned above. The five areas focused on were important in understanding just how a person was affected, and the stages they endured as well. The researchers observed that the image society displays as the perfect body is viewed through different lenses around campuses today. This topic was not only important to research, but also a step forward in building stronger confidence amongst growing individuals in college today.
The growth of ICT in this era persuade involvement of youth in e-commerce.
Authors: Bakri Siti Halimah Binti , Hassan Umi Kalsum  Binti , Ahmad Aidahani  Binti , Misran Norhailawati  Binti
Published: January 2021

Daily routine of people today is related in Information Communication and Technology (ICT) either activities and socioeconomic. The ICT through digital economy had opened new way business activity called electric commerce known as e-commerce (Berisha Shaqiri,2015). This research study about involvement youth generations doing e-commerce activities, which is to investigate the factors that persuade their involvement, to identify the medium and type of product sold in e-commerce, also to analyze the problems that facing by them in doing e-commerce selling. The research conduct by online survey questionnaire as the method to find research data and the respondents target is youth in age 18-21. This study identifies that medium effectively used in doing e-commerce is Instagram, followed by WhatsApp and then Facebook. While the most factor youth doing e-commerce determined that it able to help increase stipend and then, next factor is the power of internet to help youth selling their product. As a conclusion we can say, the involvement of youth generation as a seller in e-commerce still growth since this is the easy way to increase their monthly income.
Schumpeterian evolution of firms’ capital - labor ratio distribution
Authors:   P.N. Lebedev Physical Institute, Moscow, Leonidov A.V. ,   (NRU) Moscow Institute of Physics and Technology, Dolgoprudny, Russia, Vasilyeva E.E. ,   P.N. Lebedev Physical Institute, Moscow, Russia; (NRU) Moscow Institute of Physics and Technology, Dolgoprudny, Russia
Published: January 2021

According to J. Schumpeter innovation and imitation are two key drivers of economic growth. A quantitative realization of this idea using the formalism of kinetic equations was described in a number of papers. In most of these studies only one firm efficiency factor, the total factor productivity, was considered. In general, a description of economic evolution should include more efficiency factors such as, e.g., total factor productivity (TFP) and capital-labor ratio. The present study makes a preliminary step in the direction of two factor model development by considering central planner̕s problem of endogenous growth driven by the capital-labor ratio. The model describes an evolution of a distribution of firms on an odel developmentefficient path by considering a difference-difD.S. Ternovskyferential analogue of the Burgers’ type equation operating at a set of discrete capital-labor ratio levels. It is shown that if investment efficiency does not depend on the investment size, and production is characterised by decreasing returns to scale then firms concentrate at a certain level of capital-labor ratio. In the case of decreasing efficiency of investment with respect to its size, one observes widening of the distribution of firms in the capital-labor ratio. In addition, it is shown that the latter result holds in the case of increasing returns to scale.
Evaluation of indicators of curvilinear movement of a road train using mathematical simulation
Authors:   Bauman Moscow State Technical University, Gorelov V.A. , Yevseyev K.B. ,   Bauman Moscow State Technical University, Chudakov O.I. ,   Bauman Moscow State Technical University, Balkovskiy K.S. ,   Bauman Moscow State Technical University
Published: January 2021

Introduction: a widespread approach to the transportation of large-sized and heavy-weight indi-visible cargo on roads and terrain is the use of multi-axle wheeled transport complexes, which are road trains. At the same time, due to the significant overall dimensions, one of the most important properties of such machines is agility, that is, the ability to move along a trajectory of large curvature in a limited area, which is especially important in loading / unloading zones. Subject of research: the article presents an approach to predicting the indicators of curvilinear movement of multi-axle wheeled road trains, based on the application of the method of mathemati-cal modeling of the dynamics of body systems. Methodology and methods: the essence of the method is to create a mathematical model of the movement of a road train, represented by a system of rigid bodies, which are interconnected by kin-ematic and power connections. The simulation model developed within the framework of the study makes it possible to take into account with high accuracy the peculiarities of the interaction of the wheel propeller with the supporting surface, the redistribution of normal reactions between the sup-port modules, as well as the force factors arising in the coupling device and ensuring the interaction between the tractive vehicle and the trailer link. The mathematical description of the interaction of the propeller with the ground is based on the concept of “friction ellipse”. Using the presented mod-el, an assessment of the turnability of a wheeled road train equipped with a trailed link with swivel and non-swivel wheels was carried out. The required width along the tracks of the outer (running in) and inner (lagging) wheels was used as an assessment criterion. To assess the feasibility of using a trailed link with fully steered wheels and, accordingly, complicating the design of the machine, an additional assessment of the required power of the steering drive was carried out. Results and scientific novelty: a mathematical model of the dynamics of a road train was de-veloped. It makes possible to predict with high accuracy the indicators of curvilinear movement of wheeled vehicles, as well as to estimate the required power of the steering drive. Practical significance: a mathematical model of road train movement was developed, which al-lows a wide range of tests to be carried out to assess not only the indicators of curved-linear move-ment, but also the mobility of wheeled vehicles of any configuration as a whole.
Preliminary synthesis of algorithms for automatic control of automobile continuously variable transmissions with flexible links
Authors:   Moscow Polytechnic University, Yesakov A.E. , Kretov A.V. ,   Moscow Polytechnic University, Krasavin P.A. ,   Moscow Automobile and Road Construction State Technical University (MADI)
Published: January 2021

Variators of different operating principles and designs are of interest as components of automatic transmissions for ground transport and traction machines. At the same time, one of the most popular types of variators are the variators built on the basis of continuously variable transmissions with flexible links. The main reasons for the use of such variators in the transmissions of a number of modern passenger vehicles are, on the one hand, the emergence of flexible link designs with high durability, and, on the other hand, the widespread introduction of programmable electronic devices into automatic control systems for continuously variable transmissions. A direct consequence of the latter circumstance was the need for in-depth research aimed at synthesizing such control algorithms that would make it possible to fully use the advantages inherent in continuously variable transmissions with flexible links and minimize the operational consequences of their shortcomings. This paper makes an attempt to solve the problem of synthesizing the algorithm in a preliminary form, based on the goal of providing the vehicle with the best traction and speed properties. The presence of such an attempt will allow, having set the main parameters of a continuously variable transmission for some reason, to develop the hardware of the automatic control system. In turn, this will make it possible to synthesize a refined algorithm that takes into account the dynamics of the system, errors of meters and signal conversion devices, as well as other factors affecting work pro-cesses. When considering the described problem, various variants of the geometry of the contact surfaces of the continuously variable transmission links were taken into account and the corre-sponding mathematical apparatus were formed. The results of calculations, obtained by computer program that implements these devices, are selectively presented in the materials of the paper.
Reduced rutting of wide-grip sprinklers
Authors:   Moscow Polytechnic University, Zhuravleva L.A. , Tkhuan N.V. ,   Moscow Polytechnic University
Published: January 2021

During the process of irrigation, when moving sprinklers across the field, the wheels of the run-ning supports create a track. As the number of passes increases, so does the depth of the track. At the end of the irrigation season, it can reach 0.3-0.45 m, lead to slipping wheels and excessive wa-tering. The intensity of the process of rutting and reducing the coupling properties of the running systems of sprinkler machines is further increased in the presence of free, not absorbed water, caus-ing the formation of runoff on the track. The greatest depth of the track by the end of the season in the last undercarriages occurs due to the increase in the intensity of irrigation and the diameter of the drops of sprinklers located at the end of the pipeline. The choice of running systems should be made taking into account the characteristics of irrigated surfaces, rational ratios of span lengths, di-ameters of pipelines and sprinkler arrangement schemes. The aim of the study is to consider the im-pact of the irrigation process on the bearing properties of the soil and the formation of a track. The article presents theoretical dependences for determining the depth and width of the track for two-wheeled and three-wheeled undercarriages of wide-grip sprinkler machines. Field studies were con-ducted on “Kuban-LK1M” (Cascade) and “CASCADE” sprinkler machines. The article presents the dependence of the track depth on the number of the undercarriages with a soil bearing capacity of 110-125 kPa. The research made it possible to determine the approximate zones of application of wheel systems, depending on the bearing capacity of the soil. Analysis of the data shows that it is advisable to equip sprinklers with narrow pneumatic wheels on soils of increased strength. On soils with low bearing capacity and significant irrigation rates from 600 m3 / ha - wide-profile pneumatic tires 18-24; 23-26, 21.3-24 for “Kuban-LK1”, “Kuban-LK1M” (KASKAD), KASKAD with a pro-file width of 0.30-0.54 m, including the installation of wider tires at the end part of the machines. In addition, in conditions of low soil strength, it is possible to use tires on sprinklers with smaller profile widths than the recommended ones, but for reduced span lengths or a reduced diameter of the water pipeline.
Model of the dynamics of a wheeled vehicle for a complex of full-scale-mathematical modeling
Authors:   Bauman Moscow State Technical University, Kositsyn B.B.
Published: January 2021

Introduction. The use of the method of full-scale-mathematical modeling in “real time” opens up wide opportunities associated with the analysis of the modes of operation of the “man – vehicle – environment” system, as well as the study of the loading of units and assemblies of vehicles. The existing research complexes of full-scale mathematical modeling are suitable for obtaining most of the indicators usually determined by full-scale tests. The difference lies in the ability to fully control the course of virtual testing, recording any parameters of the vehicle movement, taking into account the “human factor”, as well as complete safety of the experiment. Purpose of research. The purpose of this work is to create a mathematical model of the dynam-ics of a wheeled vehicle, suitable for use in such a complex of full-scale mathematical modeling and assessment of the load of transmission units in conditions close to real operation. Methodology and methods. The proposed model is based on the existing model of the dynamics of a wheeled vehicle developed at Bauman Moscow State Technical University. Within the framework of the model, the dynamics of a vehicle is described as a plane motion of a rigid body in a horizontal plane. The principle of possible displacements is applied to determine the normal reac-tions of the bearing surface. The interaction of the wheel with the ground in the plane of the support base is described using an approach based on the “friction ellipse” concept. To enable the driver and operator of the full-scale mathematical modeling complex to drive a virtual vehicle in “real time” mode, the mathematical model is supplemented with a control system that communicates between the control parameter set by the driver by pressing the accelerator and brake pedals and the control actions of the vehicle's transmission units, such as: an electric machine, an internal combustion en-gine, a hydrodynamic retarder and a brake system. The article presents a block diagram of the de-veloped control algorithm, as well as approbation of the system's operation in a complex of full-scale mathematical modeling. Results and scientific novelty. A mathematical model of the dynamics of a wheeled vehicle was developed. It opens up wide possibilities for studying the modes of operation of the “driver-vehicle-environment” system in “real time”, using a complex of full-scale mathematical modeling. Practical significance. A mathematical model of the dynamics of a wheeled vehicle was devel-oped. It is supplemented with an algorithm for the distribution of traction / braking torques between the transmission units, which provide a connection between the driver's pressing on the accelerator / brake pedal and the control parameters of each of the units.
Results of field studies of a tractor of traction class 1,4 with an elastic damping mechanism in a power drive
Authors:   Federal Scientific Agroengineering Center VIM, Sen'kevich S.E. , Il'chenko YE.N. ,   Federal Scientific Agroengineering Center VIM, Godzhayev Z.A. ,   Federal Scientific Agroengineering Center VIM, Duryagina V.V. ,   Southern Federal University
Published: January 2021

The topic of this paper is analyzing the results of field studies of a tractor with an elastic damping mechanism in a power drive and its operational efficiency assessment in comparison with a serial tractor. The subject of the research is a tractor with an elastic damping mechanism in a power drive as part of a plowing unit with a mounted plow. The purpose of this work is a detailed analysis of the influence of the parameters of the elastic-damping mechanism on the performance of a tractor with a plow. Carrying out such studies makes it possible to obtain new experimental data on the operation of the elastic damping mechanism in-stalled in the power drive of a tractor when aggregated with a plow. The control experiments were carried out in the same field during the summer and autumn peri-ods of one year. The benchmark for comparative experiments was the same tractor, but with a blocked elastic damping mechanism (for brevity, it is called “serial”). The results were processed on a personal computer using a software package. To analyze energy efficiency, a conditional classifi-cation of sample variability based on the coefficient of variation was used. Spectral analysis was performed to study numerical slip data. The indicators of the energy assessment show that the unit with an elastic damping mechanism in the power drive of the tractor has better performance (travel speed, productivity and fuel consump-tion per hectare) than a similar unit with a more rigid transmission. The elastic damping mechanism creates more favorable conditions for the formation of the nature of the load of the nodes, with un-steady and steady-state modes of motion. Statistical analysis of numerical data on slipping showed that the use of the mechanism makes it possible to reduce the mathematical expectation of slipping. Analysis of spectral characteristics indicates that the elastic-damping mechanism absorbs frequen-cies, being a filter when aggregated with various tools. Everything mentioned above indicates a sig-nificant improvement in the characteristics of the unit when using an elastic damping mechanism.
Investigation of the relationship between theoretical and actual turning radii of a tracked vehicle using mathematical modeling
Authors:   Bauman Moscow State Technical University, Stadukhin A.A.
Published: January 2021

Introduction. Determination of the traction force and power required in a turn by a tracked ve-hicle is based on analytical dependencies given in classical literary sources. In this case, the de-pendence of the theoretical and actual turning radius is usually not described accurately enough. Subject of study. A study of the dependence of the theoretical and actual turning radius and the influence of the parameters of the undercarriage of the tracked vehicle, the characteristics of the support base and the mode of movement on it was made. Methodology and methods. The study was carried out using a specially developed stationary rotation tracked vehicle (TV) model, which differs by taking into account the redistribution of nor-mal reactions and implementation, allowing one to quickly carry out multifactorial experiments. The rotation of the TV in the model is described as a plane motion of a rigid body. In contrast to the classical approaches, the model allows one to study the rotation of the TV at a speed close to the critical drift. Results and scientific novelty. During computational experiments, the parameters of the chassis of the TV, the properties of the support base, as well as the speed of movement and the actual turn-ing radius were varied. It was found that the classical dependences of the actual and theoretical turning radius need to be refined when driving at a speed close to the critical drift, while the form of the dependence is determined by the height of the center of mass of the TV. Practical significance. These features should be taken into account both when assessing the speed of the vehicle and determining the required thrust-to-weight ratio, and when working on the development of active safety systems for tracked vehicles.
Optimization of the design and experimental study of the stress-strain state of the rear suspension balancer of an all-terrain vehicle
Authors:   Bauman Moscow State Technical University, Shabolin M.L.
Published: January 2021

Reducing the curb weight of wheeled vehicles has long been one of the priority areas of work of automotive engineers, since this can significantly improve the operational properties of a wheeled vehicle: improve dynamics, passability, reduce fuel consumption and emissions of harmful sub-stances. A significant proportion of the vehicle's curb weight belongs to highly loaded parts of the frame, transmission and suspension. Therefore, the creation of lightweight, highly loaded parts will make a significant contribution to reducing the curb weight of the whole vehicle. The paper describes the application of the topological optimization method based on finite ele-ment modeling in the design of highly loaded parts of the chassis of vehicle. An example of the syn-thesis of the power circuit of the rear suspension balance bar of an all-terrain vehicle with a descrip-tion of the design model, load modes and interpretation of the results is shown. The optimization problem was solved using a finite element model of varying density. Minimization of the potential energy of deformation was used as an objective function, and the target volume in fractions of the original design space was used as a limitation. A comparative analysis of the obtained design with analogous designs is presented. The formulation and results of an experimental study of the stress-strain state of the optimized balance bar are described. As a result of optimization, it was possible to achieve a reduction in the weight of the balance bar to 49% in comparison with an analogue design while maintaining the required strength. Experi-mental verification of the bearing capacity of the balance bar showed the need for more thorough verification calculations of optimized parts, including taking into account manufacturing and as-sembly errors.