bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of iron-doped zinc oxide (Fe-ZnO) nanoparticles by using several stabilizers
Authors: Muktaridha O , Adlim M , Suhendrayatna S , Ismail I 
Published: May 2021

Abstract
Studies on the effect of the stabilizer of chitosan, citric acid and urea for preparation Fe-doped ZnO have been conducted. Both ZnO and Fe were prepared from each salt precursor solution. The Zn2+ was added fist and subsequently Fe2+ by dropwise method into each stabilizer solution before converted into the hydroxide compounds before annealing. All metal ion solutions precipitated out after 7 minutes of NaOH addition except in urea stabilizer, where the solution remained in the colloidal form for more than 30 minutes. The hydroxyl ions are required for ZnO formation, but it weakens chitosan and citric acid stabilizing capacity, which instigated ZnO particles to be highly agglomerated. Each stabilizer generated a smaller ZnO crystallite size compared to the control sample. Fe-ZnO crystallite size prepared using chitosan, citric acid and urea as the stabilizer was 14.75, 23.29 and 22.51 nm, respectively. The crystallite size of Fe-ZnO that was prepared without stabilizer (control) was 32.89 nm.
The utilization of vehicle waste-oil as a material source for preparing carbon dots
Authors: Hasrudin A , Abidin Z , Hiedayati N , Kharisma D 
Published: May 2021

Abstract
Synthesis of carbon dots (c-dots) from vechile waste-oil is one of the alternatives for reducing the burden of environmental pollution. This study aimed to develop a green and economical strategy to produce C-dots by using motor oil waste. C-dots were synthesized by heating motor oil waste in the various percentage of sulfuric acid solution (95, 70, 30, and 0% H2SO4). The synthesized C-dot was characterized by UV-Vis spectrophotometry and Fourier Transform Infrared (FT-IR) spectroscopy. The result showed that the carbon dot produces blue color at 365 nm of UV light. This color was attributed to the oxidation of chemical content in motor oil waste. Therefore, four peaks were obtained at 203 nm, 204 nm, 215 nm, and 210 nm for all samples. Based on FT-IR spectra, the most prominent sample difference was observed at peak 1630 cm−1. The characteristic band of the carbonyl group was identified at the c-dot concentration (70 and 95%) but was not observed in the c-dot concentration (0 and 30%). The presence of carbonyl groups caused the fluorescent color to gradually shift from dark blue to light blue.
Determination of the Aflatoxin levels in Corn (Zea mays, L.) during storage process
Authors: Mulyati A H , Sutanto  , Warnasih S , Herlina E 
Published: May 2021

Abstract
Aflatoxin contaminant in corn being a serious problem, due to its toxicity. This contamination was influenced by the storage and treatment process. During storage, the aflatoxin level was influenced by the water content of corn seed. In this study, the water content were performed by gravimetric method, while the aflatoxin contents have been carried out by ELISA and HPLC methods. The corn seed samples were obtained from Tangerang, Cikande, and Cirebon. The results showed that the aflatoxin content were increased in fourth-week storage. The analysis of the aflatoxin content using the ELISA method showed that corn seed obtained from Tangerang, Cikande, and Cirebon were 74, 06 ppb; 9.33 ppb; 28.67 ppb respectively, while the HPLC method showed that the aflatoxin content were 75.02 ppb; 9.83 ppb; 28.43ppb respectively. The results also showed that the water content in the corn seed obtained from Tangerang, Cikande, and Cirebon were 10.64%; 10.17%, 10.25% respectively on fourth-week storage. In conclusion, the aflatoxin content in corn seed from Cikande and Cirebon were in accordance with SNI standards, while corn seed from Tangerang contain aflatoxin was above 50 ppb.
Effect of serving temperature on the nutritional quality of cereal foods
Authors: Warnasih S , Mulyati A H , Sutanto S , Herlina E 
Published: May 2021

Abstract
Cereal is one of the oat-based food products that contain high dietary fibre and nutritional value. One of the factors that affect the nutritional quality of the cereal during serving is the temperature of the water used for brewing. This study was carried out to evaluate the effect of serving temperature on the nutritional value of ready-to-eat cereal foods. The sample consisted of 4 types, i.e instant oat (A and B), and quick cook oat (A and B). Each sample was brewed using four different water temperatures, namely 40, 60, 80, and 100 °C. Then the nutritional content analyses were carried out included protein, fat, dietary fibre, and magnesium, also the organoleptic test with the panellist. The results showed that the treatment of the four serving temperatures resulted in levels of protein, fat, fibre, and magnesium which were significantly different, while the serving water temperature of 100 °C resulted in higher levels of dietary fibre. The sample that was most preferred by the panellists was the sample that was brewed with water with a temperature of 60 °C, while the sample that was least preferred was the sample that was brewed with water at 40 °C, both in the instant oat and quick cook oat samples. Therefore, water with a temperature of 60 °C was recommended for serving cereals.
Application of simple kinematic model from flexion movement of upper-limb with RGB-D camera perspective
Authors: Barri M H 
Published: May 2021

Abstract
This study describes the use of an RGB-D camera for the assessment of the upper-limb movement for stroke rehabilitation patients. The assessment process is carried out by making comparisons between patient movements and simulated movements. The motion simulation is modelled by the kinematics model of the 6 DoF arm with extended flexion motion. Tests were carried out on 13 normal patients with movement schemes that often appear in the rehabilitation process. The results show that the use of the 6 DoF model results in better accuracy and calculation time than using the 8 DoF model.
Beams destruction by explosion of non-contact charges of condensed explosives in water
Authors: Volodin G T , Kochergin D S 
Published: May 2021

Abstract
The analysis of effects of the hydrodynamic field created by the explosion of condensed explosive charge on the simplest construction element in the form of beams in the water is performed. The features of the load due to the location of the beam in the water are taken into account by the attached mass introduction. The classical condition of the element destruction is used, according to which it is necessary that the stress in the element is greater than the ultimate resistance of the material and refined of O.E. Vlasov’s formula on the proportionality of the bending moment to the acting explosive load pulse is used.
Torsional waveguide modeling of an ultrasonic medical instrument
Authors: Gouskov Alexander Mikhailovich , Grigoryev Yuri Vsevolodovich , Pyae Phyo Aung 
Published: May 2021

Abstract
Based on analytical solutions for several torsion waveguides, transition matrices are derived, which are then used to calculate torsional vibrations using initial parameters. The paper contains a comparative analysis of different types of concentrators. As the waveguide’s design scheme, a rectilinear rod of the variable cross-section with various fastening types is adopted. The method of numerical determination of natural frequencies and waveforms of the waveguide of an ultrasound medical instrument (UMI) is presented. For a given waveguide layout, the amplitude angles of rotation and torques in the UMI are calculated at a specific frequency of oscillation excitation. A satisfactory agreement of the obtained results is demonstrated.
The analysis of the laminar-turbulent transition onset for the Couette flow in the flat channel with the velocity profile periodic background perturbation
Authors: Kolodezhnov V N 
Published: May 2021

Abstract
To predict the laminar-turbulent transition, we adopted an approach, which is based on the transverse viscosity factor threshold addition hypothesis. Taking into account the conditions imposed on the corresponding dimensionless complexes within the framework of this approach, we analysed the transition onset for the Couette flow in the flat channel with consideration of the velocity field perturbation initial periodic background. The critical value for the Reynolds number was obtained, which is in satisfactory agreement with the known experimental data.
Point-like mechanical singularity in the method of boundary states
Authors: Polikarpov M V , Penkov V B , Levina L V 
Published: May 2021

Abstract
This paper presents an effective technique for solving some spatial problems in the theory of elasticity, particularly for a bounded set of point-like physical singularities. This technique development involves the advanced energy method of boundary states (MBS) for a class of solutions with singularities. A test problem for a single singularity such as the center of expansion complying with the proposed technique calculations reliability has been solved and analyzed. The use of the method of boundary states demonstrates the efficiency of the technique in solving problems with many centers of expansion and concentrated forces in an unbounded medium. The results of problem solving are displayed in a convenient graphical form.
Passive transport safety based on the calculation of the temperature regimes of brake units taking into account their heat dissipation and thermal resistance to heat dissipation
Authors: Belokurov V P , Belokurov S V , Shtepa A A , Korablev R A , Busarin E N 
Published: May 2021

Abstract
The article discusses the conditions for increasing the passive safety of vehicles due to the use of the results of calculating the temperature regime in frictional friction pairs in the design of brake assemblies, both taking into account their active heat dissipation, and taking into account the contact thermal resistances along the path of the dissipated heat flows. This temperature calculation allows, at the design stage of new brake units, to determine their optimal geometric arrangement, taking into account the increased thermal dynamics of friction of friction pairs during their active heat dissipation. In addition, it becomes possible to recommend the optimal frictional pairs of friction in the brake units, taking into account their thermal stability. The use of the above thermal calculations will ensure an increase in the performance of the brake units, which, ultimately, will provide an increase in the passive safety of vehicles.
Development of a stimulating mechanism for the coordinated management of agents’ resources in the implementations of joint projects
Authors: Bondarenko Yu V , Azeez A E , Azarnova T V , Barkalov S A 
Published: May 2021

Abstract
This article is devoted to the development of a mechanism that makes it possible to increase the efficiency of agent resource management by forming an optimal package of projects and a coordinated distribution of profits from its implementation. A feature of the proposed mechanism is its focus on stimulating agents to be active at the stages of initialization and implementation of merger projects. The proposed approach is based on mathematical models and methods. At the first stage of the mechanism, it is proposed to find the optimal package of projects on the basis of a discrete optimization model. To implement the second stage, associated with the distribution of the obtained profit, the concept of an agreed profit distribution is introduced and its connection with the solution of a cooperative game is described. The basis of the stage is the algorithm of the agreed profit distribution taking into account the activity of agents. The developed software product allows you to automate the practical calculations of the stages of the mechanism.
Application of the variational method for studying stability of the 3D Lotka — Volterra system
Authors: Tikhomirov V , Isaev R 
Published: May 2021

Abstract
The paper investigates the stability of the Lotka — Volterra dynamic system ≪predator — two preys≫ with the help of variational method. This method is applicable for studying equilibrium stability non-linear dynamical systems of any kind and in any dimension. It approves its effectiveness even in cases where the use of the Lyapunov function causes great difficulties (for example, when solving tasks of large dimension). The proposed method is based on a variation method for estimating the rate of phase-state metric change for the perturbed system when the variable t → ∞. The disadvantage of the variation method is the fact that this method provides only the necessary conditions of stability. However, its it forms the first step in studying the stability of non-linear dynamical systems of any kind and any dimension.
Algorithm and model for improve the avoiding of deadlock with increasing efficiency of resource allocation in cloud environment
Authors: Bondarenko Yu V , Azeez A E 
Published: May 2021

Abstract
Recently, cloud computing has been the most popular method among all other promising technologies that provides the service for many users at the same time. all users can reach and use the resource that is provided by the Virtual Machines (VMs). Hence users process, data must arrive to the resources to perform as a disturbed system, which provides dynamical scale services and virtualized resources. As a result of limitation of resources, the deadlock status may occur in such type of systems. In this paper, we have designed an algorithm that could increase the efficiency of deadlock avoidance. Our technique will use the attribute of execution time in the process to get better resource allocation in additional to the checking system to stay in safe state and free of deadlock.
Analysis and visualization in graph database management systems
Authors: Dubrovin A S , Ogorodnikova O V , Tsarkova E G , Andreeva E A , Kulikova T N 
Published: May 2021

Abstract
The following questions of visual interpretation of the data in the graph models of data are considered in the work with graph database management system (DBMS) with DBMS Neo4j as an example; convenience of data visualization in the form of graphic images as compared with the electronic worksheets was confirmed; a high connectivity of data was revealed for DBMS NEO4j. To do all these algorithms from DBMS NEO4j library are employed. Clusterization is applied for the estimation of the quality of affinity for the predetermined data sets. Here method of silhouette assessment is used. Basing on the performed experimental studies a conclusion was made concerning the quality of revealing the similarity between the predetermined data sets with the use of graph DBMS NEO4j.
On Undecidability of Subset Theory for Some Monoids
Authors: Dudakov S M 
Published: May 2021

Abstract
Early we (with B. N. Karlov) have proved the following claim for the infinite cyclic monoid ℋ. Let exp ℋ be an algebra of finite subsets of ℋ with the same operation, exp ℋ must be a monoid again. So the theory of exp ℋ is equivalent to elementary arithmetic. Thus, the theory of the monoid exp ℋ is undecidable. Here we consider an arbitrary commutative cancellative monoid ℋ with an element of infinite order, and generalize the previous claims to the corresponding monoid exp ℋ.
Architecture of the decision-making system concerned to the management of repair of the motor-vehicle transport at the large-scale enterprise
Authors: Egorov S Ya , Kalach A V , Salih H S , Zatonsky A V , Felker M N 
Published: May 2021

AbstractArchitecture of the system for support of the decision-making for the transport vehicles enterprise providing the balance between reliability and costs. This allows providing a decision-making person with reliable and qualitative information concerning consequences of the choice between this or that kind of repair. Technical realization of this approach is implemented with the use of 1C-accounting software.
Optimization of the number of pumping stations when tracing distribution lines of the external fire-fighting water supply system
Authors: Kalach A V , Cherepanov E A , Dmitriev E V , Akulov A Yu 
Published: May 2021

Abstract
New graphical algorithms of planning, optimal deployment of the pumps for the external firefighting are proposed and mathematical models of optimization when constructing external various water-supply pipeline networks for fire hydrants in a separate community that does not involve highways or special roads are also presented.
Methods for prediction of the avalanche danger
Authors: Kalach A V , Solovyov A S , Karpov S L , Martinovich N V , Kalyuzhina G S 
Published: May 2021

Abstract
The work considers methods for the prediction of the avalanche danger. It shown that for the local forecasts the most efficient way is to simulate snow mass by the particles dynamics technique. Basin on this model it is possible to predict the critical parameters for the avalanche sliding, the character of motion of snow mass, the force and energy of its impact on the movable and immovable obstacles with different shape and, hence, a destructive avalanche ability.
Support technologies for management of the land flood protection
Authors: Kalach A V , Arifullin E Z , Nicheporchuk V V , Kalach E V , Oblienko A V 
Published: May 2021

Abstract
The problems of management for the safety of territories are considered as well as their application with the landfloods as an example. Model of organization of the informational resources is proposed. Models of decision-making in the conditions of uncertainty are described as well as the architecture of information-analytical systems allowing integration of the new technologies for digitization of economics.
Analytical model for calculating the effectiveness of the modified access control subsystem of the information security system against unauthorized access in automated systems
Authors: Batskih A V , Bulgakov O M , Drovnikova I G , Krisilov A V 
Published: May 2021

Abstract
The paper considers an analytical model for calculating the performance indicator of the access control subsystem of the information protection system against unauthorized access in an automated system, the use of which allows to significantly simplify the calculation and increase its accuracy. The dynamics of subsystem functioning is described using a stochastic Petri net using the Laplace transform. Using the example of the standard information protection system against unauthorized access “Strazh NT 4.0”, the results of calculations of probabilistic and temporal characteristics of the model “Starting the PC and identifying the user” are presented, which describes the functioning of the access control subsystem when it is modified by implementing additional authentication based on the regular user keyboard handwriting recognition. Obtaining analytical dependencies of transition probabilities between the states of a modified subsystem allows optimizing its operation and verifying compliance with the requirements for the probability of performing functional tasks in a given time, while increasing the overall level of security of the automated system.
About building a basis surface in inverse kinetic problems for non-break processes of diene polymerization
Authors: Gizzatova E R , Ismagilova A S , Podvalny S L 
Published: May 2021

Abstract
The work contains a mathematical description of diene polymerization with a neodym-based Ziegler-Natta catalysts. The resulting system of differential equations was reduced from infinite to finite by the method of moments. For this, the basis of nonlinear parametric functions was searched with a method allowing obtain expressions that reflect the kinetics of the polymerization process. The obtained basis of two functions enables us to construct a surface containing local regions of the minimum of the objective function which define the starting points for search of optimum kinetic constant values.
Image texture model based on energy features
Authors: Lyasheva M M , Lyasheva S A , Shleymovich M P 
Published: May 2021

Abstract
In information processing and control systems based on computer vision technologies, it is necessary to provide an effective indicative representation of images for their subsequent analysis. One of the widely used approaches is based on the construction of texture models. In this paper, the description of the texture using energy features is considered. The proposed model is a set of weights of image pixels reflecting their significance from the point of view of image perception. The significance of the pixel is estimated using the energy of the coefficients of the orthogonal discrete multiresolution wavelet transform. The paper presents expressions for calculating pixel weights and shows that the resulting texture models can be used to classify images.
Development of a cloud SaaS service for a comprehensive research of polymerization processes
Authors: Miftakhov E , Mustafina S , Mikhailova T , Podvalny S 
Published: May 2021

Abstract
The article is devoted to the description of the network architecture of the developed cloud SaaS service for the implementation of a comprehensive study of polymerization processes. The main problem of using local software systems for such tasks is briefly voiced. The main methods and mathematical approaches that allow solving the direct problem of predicting the main molecular characteristics of the produced polymer product for various loading modes of the reaction system and the inverse problem of identifying some of the unknown kinetic parameters are considered. Methods and approaches to the development of algorithms and software are considered separately. As part of the cloud service being developed, a three-tier architecture for accessing data and computing resources is described in detail, the main tasks of each level and the advantages of using this approach are described. The hardware and system requirements for the computing nodes of the developed network application have been written out.
Suspended particle transport process modeling based on 2D and 3D models
Authors: Chistyakov A E , Protsenko E A , Kuznetsova I Y , Nikitina A V 
Published: May 2021

Abstract
In this paper, suspended particles transport mathematical model is proposed and investigated. The considered model includes the following factors: the aquatic environment movement; variable density depending on the suspension concentration; multicomponent suspension; change in the bottom geometry as suspension sedimentation result. The 3D diffusion-convection equation approximation based on splitting schemes into 2D and one-dimensional problems. In the paper, convective and diffusive transfer operators’ discrete analogs in the case of partial fullness of the cells are used. Based on the fullness function, the calculated area geometry is described. The difference scheme, which is linear combination of the Upwind and Standard Leapfrog difference schemes with weight coefficients obtained from the condition of minimizing the approximation error, is used. This scheme is designed to solve the impurity transfer problem at large grid Peclet numbers. Based on the results of numerical experiments, conclusions are drawn about the advantages of the 3D model of suspended particle transport over the 2D model. The results of numerical experiments on modeling the multicomponent suspension deposition are presented.