bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of parameters of induction motor with error of speed sensor
Authors: Ivanov D V , Sandler I L , Mitroshin D I , Terekhin M A , Antonova V V
Published: June 2022

This paper proposes a new approach to parametric identification of induction motor with error of speed sensor. The ordinary least squares (OLS) estimates are shown to be biased. Generalized total least squares (GTLS) with a singular covariance matrix of the error are propose for estimation of K parameters of induction motor. Identification of parameters takes place in 2 steps. At the first step, two K parameters are estimated using GTLS with a singular error matrix. At the second step, the remaining three K parameters are estimated. An equivalent augmented system is used to solve a biased normal system. Based on the simulation results, a comparison of the accuracy of the estimates of the proposed algorithm and ordinary least squares estimates is given.
Development of an electrical energy device for technological machines
Authors: Plieva M T , Gavrina O A , Ignatev I V , Bryanskikh T B
Published: June 2022

The article presents the results of a comprehensive analysis and development of an electric power metering device on device for technological machines on the basis of a comprehensive heat and power survey. The result of the research showed that it is advisable to use electronic electric energy meters to account for electric energy on excavators and drilling rigs, which provide a smaller error compared to induction ones. To account for electrical energy on excavators and burst machines, it is advisable to use electronic meters of electrical energy, which provide a lower error in comparison with induction meters.
Comparative analysis of the speed of concurrent algorithms in solving the forward kinematics of a hexapod robot
Authors: Malyshev D , Pisarenko A , Tereshchenko A
Published: June 2022

The paper discusses the use of parallel computing on a central processing unit (CPU) to solve the forward kinematics of a parallel hexapod robot. The paper proposes two algorithms to solve the forward kinematics. The first is based on the direct use of the system of equations of kinematic relations of the mechanism. The approximation of a set of system solutions represents a problem of a nine-dimensional grade. The second approach is based on the approximation of a set of solutions to the system of inequalities of a three-dimensional grade. A software package for implementing the proposed algorithms was developed. The comparative analysis of the effect of parallel computing on the speed of the presented algorithms was carried out.
The impact of the passage of long-distance trains on the required electrical capacity of the transport infrastructure facilities of the Eastern polygon of Railways
Authors: Akhmetshin A R , Suslov K V , Olentsevich V A , Gladkikh V A , Karlina A I , Baraboshkin K A
Published: June 2022

Increasing the profitability and profitability of railways can be achieved through a phased study, identifying the most problematic areas and a competent, well-planned and economically sound solution to these problems. To do this, the road management structures of individual departments must constantly analyze and develop design solutions for the development and reconstruction of railway transport. Particular attention in terms of increasing freight turnover should be paid to ensuring the required electrical capacities of all transport infrastructure facilities of the Eastern Railway Range, which is currently the most strategically significant in the Holding. In order to optimize the transport service of the eastern direction, increase the cargo turnover of the Baikal-Amur and Trans-Siberian Railways, first of all, it is necessary to provide the required electric capacities of transport infrastructure facilities. It is possible to achieve efficient and reliable power supply for the railways of the Eastern Range, to exclude the possibility of non-export of all categories of cargo, provided that a coordinated integrated approach to the development of the power grid sector of Siberia and the Far East is developed. Such an approach should provide for a phased strengthening of the power system of facilities.
Using new grouting materials during repair and insulation works
Authors: Kadyrov R R , Mukhametshin V V , Kuleshova L S , Mingulov I Sh
Published: June 2022

The paper presents the results of using new materials during repair and insulation works (RIW) in the conditions of Tataria fields and assesses the possibility of their application for the fields of other regions. The proposed new RIW technologies enable to increase oil recovery, reduce the water cut of the manufactured products, and intensify the oil production process. The article discusses the use of vinyl polymer VITAM and organosilicon compounds.
Polymer materials used to reduce waterjet wear of pump parts
Authors: Mamazhonov M , Shakirov B , Matyakubov B , Makhmudov A
Published: June 2022

The article presents the results of studies of the degree of influence of the operating mode of the centrifugal pump on the intensity of the water jet at constant values of the sediment concentration P = 20 kg/ m3, particle diameter d = 0.25…0.5 mm, test duration T = 2 hours and shaft speed n0 = 2900 rpm. Experiments were carried out on pump feeds from 0.5 Qopt to 1.25 Qopt with various materials and polymer coatings that were applied to the surfaces of the blades made of St.3. The best adhesion of the polymer coating is obtained at a metal temperature of 21°C. Polymer materials based on epoxy resin with silicon carbide have the highest wear resistance, while silumin shows low wear resistance. When testing ground pumps, it was found that parts made of electro corundum on an epoxy-phenol-formaldehyde bond, in comparison with parts made of wear-resistant cast iron, increases the service life of pumps 3 - 8 times.
Magnetization of alloys of (Tb1−xYx)0.8Sm0.2Fe2 system in stationary and pulsed magnetic fields
Authors: Umkhaeva Z S , Ilyushin A S , Aleroeva T A , Tereshina I S , Pankratov N Yu
Published: June 2022

The paper presents the results of studying the alloy magnetization of the multicomponent system (Tb1−xYx)0.8Sm0.2Fe2. The substitution parameter in this system takes the following values: x = 0, 0.2, 0.4, 0.6, 0.8, 1. In the system, the atoms of magnetic terbium were replaced by atoms of weakly magnetic samarium and nonmagnetic yttrium. X-ray diffraction analysis determined the structure and lattice constant for all compositions. Phase analysis was carried out. It is known that by varying the concentration of components, temperature, and external fields, one can successfully influence the magnitude of exchange interactions leading to one or another type of magnetic ordering in the rare-earth intermetallic metals. Therefore, the main goal in this work was to investigate the possibility of observing the magnetic phase transition – ferrimagnetism – ferromagnetism - in the alloys of the system from the curves of the field dependence of magnetization in strong fields up to 60 T. The studies were carried out at the liquid helium boiling point. The main magnetic characteristics of the alloys of this system were determined, such as saturation magnetization σs, magnetic moment per formula unit μ and magnetic moment μFe on iron atoms. Their dependences on the concentration of yttrium were established. The possible values of the magnetic moment per formula unit in the case of ferromagnetic ordering of these alloys were calculated theoretically. It was concluded that these fields are insufficient to observe the ferrimagnetism – ferromagnetism phase transition.
Analytical calculation of the coefficient of increasing the moment of resistance to milling the ground when the cutter hits the stump
Authors: Yablonev A L , Misnikov O S , Zhukov N M
Published: June 2022

One of the main operations in peat soil processing is milling. The entire subsequent production process depends on the quality of the milling. The presence of wood inclusions in the soil greatly complicates the work. The sharply increased moment of loading that occurs when the cutter hits the stump is capable of removing both the transmission elements and the drive of the milling unit from the operational state. Therefore, at the design stage, it is necessary to take into account the dynamic loads arising from the meeting of the cutter with wood inclusions. Attempts to describe this fact were made earlier by various authors, but due to mathematical and methodological errors, they were not crowned with success. In this article, an attempt was made to "work on errors", which allowed one, taking into account all the previous errors and inaccuracies, to achieve the desired result.
Diagnostics and reliability of current receivers
Authors: Mizaev M M , Malozyomov B V , Halikov I H
Published: June 2022

The most vulnerable element of modern electric buses, which are dynamically charged, are pantographs. The article describes the main reasons for the wear and tear of pantographs. The calculation of the probability of failure-free operation of the pantograph systems is made.
Main patterns of stress corrosion forming the basis for control, evaluation and deceleration methods
Authors: Khasanova A R
Published: June 2022

The most effective methods of control during incubation of development and cracking were systematized and proposed on the basis of the developed physical model of corrosion cracking of main gas pipelines under stress. It was established that this is one of the most advanced methods for testing gas pipelines for stress corrosion cracking – this is a magnetic location method.
Experimental seeders for sowing unseeded seeds
Authors: Farmonov E T , Arifjanov A M , Farmonova F E
Published: June 2022

Information on the use of seeders for sowing seeds of agricultural crops and their converted experimental seeders for sowing unseeded seeds is given in this article. It has been shown that such sowing units do not fully meet the agro technical requirements for sowing unseeded seeds. Most of the research focused on the issues of unloading seeds from the bunker, but did not study the laws of their movement inside the bunker. The authors have proposed a separate two-section hopper for the seeding row of the seeder when sowing unseeded seeds of fodder plants in deserts. Inside the two-section hopper of the proposed seeder, mathematical expressions are set that make it possible to determine the regularity of the movement of unseeded seeds and the time of their fall.
Screw conveyor with anti-friction polymer coating for cotton transportation
Authors: Irgashev A A , Ergashev F A
Published: June 2022

Screw conveyors used in the ginning industry when interacting with raw cotton, significantly damage it and reduce the quality of the products. The article presents the results of a study of the effect of antifriction polycaproamide composite coating applied to the surface of the screw and the chute on the quality of cotton fiber and seeds, as well as on the productivity and power consumption of the screw conveyor for cotton. During the production tests, measurements are made of the magnitude of the linear wear of the coating on the surface of the screw and chute. It is established that with the recommended thickness of the coating of APCC-I 600–700 microns, its durability under operating conditions at the cotton gin plant, with two-shift operation during one season, will be fully ensured.
An analysis of reliability of electric submersible centrifugal pumps
Authors: Khabibullin M Ya , Suleimanov R I
Published: June 2022

The average operating time before structural and technological failures of the submersible part of a typical ESP is 64.5–81.9% of the average operating time of new ESPs. Given that the set of typical ESPs includes a significant share of repaired and mixed (equipped with new and refurbished units) installations, this fact can be interpreted as evidence of poor quality of repair. The data obtained from Tatneft and Bashneft companies agree with this conclusion. The data provided by Nizhnevartovskneftegaz company do not contradict this conclusion. The high values of Ttkt obtained by Rosneft-Samaraneftegaz are a consequence of poor identification of the causes of ESP lifting during control operations, as a result of which some failures are treated as design and technological ones.
Estimation of parameters and operating modes of the screw cutting device
Authors: Alijanov D , Jumatov Y
Published: June 2022

The research is directed from the theoretical aspect to the development of the design of a new grinder, characterized by low energy and metal consumption. The work investigates the relationship of geometric parameters and speed modes of operation with quantitative and qualitative indicators of the screw cutter system. It is possible to increase the degree of chopping of the stems only by reducing the average cut length, i.e. by increasing the rotational speed screw knife. The experiments shows the average slice lengths and the corresponding productivity of the screw cutting pair depending on the speed of rotation of the knife. That for compliance with zootechnical requirements, modes n= 550-650 rpm.( lav = 8-4,5 sm ) - with vertical loading, and n=400-450rpm (lav = 5,5-4 sm) – at inclined feed at an angle β = 450. An increase in the frequency of rotation of the knife leads to a sharp decrease in the productivity of the cutting pair. The above numerical examples are selected in accordance with the parameters of the experimental setup and show good agreement with the experimental results.
Diagnostics of power transformers operating for many years in the power supply system through gases in the composition of transformer oil
Authors: Denmukhammadiev A M , Yusupov D T , Shoyusupov Sh A , Djalilov A U , Nazarov O A
Published: June 2022

Oiled power transformers and autotransformers 40-60 years ago are still in operation in Uzbekistan. At the same time, diagnostic methods for determining faults in transformers and autotransformers remained the same. This article partially analyzes the factors affecting the oils of power transformers and autotransformers used in the agricultural sector. It is known that transformer oil performs the functions of cooling and insulation. During use, the oil is in direct contact with air through the respiratory system. There is a process of transition of moisture and various gases in the composition of the air into the composition of the oil. By the composition of gases, it is possible to determine the reasons for the deterioration in the quality of the main and additional insulation of oil-immersed power transformers. The issues of influence on the state of insulation of marsh gases appearing inside (at the bottom) of the tank of oil transformers and partial discharges in oil-gas medium have been little studied.
Analysis of theoretical cycle of thermal engines and improvement of diesel mixing process
Authors: Khakimov B B , Rajabov N Q , Xaydarov T A , Kalandarova S T , Kulmamatov O A , Khudoyorov O , Murodov T
Published: June 2022

This article provides a theoretical analysis of the diesel cycle, the device and principle of operation of the proposed atomizer with a replaceable mesh turbulator. This ensures the formation of a homogeneous fuel mixture in the vortex chamber and the completeness of its combustion without toxic emissions. The importance of the scientific work provides for the need to improve the toxicity of the exhaust gases of thermal diesel engines and their fuel efficiency.
The methodological specificity of measuring surface tension by the methods of large drop and maximum pressure in a drop
Authors: Dadashev R Kh , Kutuev R A , Sozaev V A
Published: June 2022

A comparative analysis of the experimental data on the surface tension (ST) of low- melting metals, obtained by the method of maximum pressure in a drop and the method of a large drop, shows that the values of ST obtained by the large drop method for all studied metals are noticeably higher than those obtained by the method of maximum pressure in a drop. The reasons for such discrepancies, although in some cases they exceed the total errors of the ST measurement by the indicated methods, have not yet been clarified. In this regard, the paper gives a comparative analysis of the methodological specificity of measuring the surface tension by the methods of maximum pressure in a gas bubble or a drop and a lying or “large” drop. It is shown that these methods are theoretically substantiated, technically perfect, have a sufficiently high accuracy and are relatively simple. Based on the identification and critical analysis of the influence of the main factors on the measured value of the surface tension, the main reasons for the discrepancy between the experimental data on the surface tension of low-melting metals obtained by different methods are determined. It is shown that the underestimated ST values obtained by the method of maximum pressure in a droplet are due to the fact that all factors influencing the measured value of surface tension are directed towards a decrease in its value. Although the influence of each of these factors separately is insignificant, they together lead to a noticeable decrease in the value of surface tension. It is shown in the work that the method of maximum pressure in a drop, being the most accurate method for measuring ST, gives somewhat underestimated ST values for all low-melting metals.
Longitudinal vibrations of underground pipelines of finite length with account for the node weight on the ends
Authors: Shadmanova G , Karimova K , Khusainov R , Khusainov S
Published: June 2022

The paper presents an analysis of the dynamic response of an underground main pipe under the action of longitudinal wave, propagating in soil along the pipe. The outer surface of the pipeline is in contact with soil along the pipeline axis according to the elastic- viscous law, and the ends of the pipeline are connected to massive nodes by elastic elements. Using the Fourier method, an analytical solution to the problem of longitudinal vibration of an underground pipeline, pliantly fixed by nodes at its ends, is obtained. The problem of longitudinal vibration of an underground pipeline with visco-elastically fixed nodes at the ends is solved numerically. Longitudinal wave in soil is taken as a traveling sine wave. The paper presents a comparative analysis of the results for some values of seismic wavelengths, the ratio of the wave propagation velocity in soil and in the pipeline, the coefficients of elastic and viscous interaction. The viscosity coefficient of interaction at the "pipe-soil" system contact leads to attenuation of the wave front in the underground pipeline. For soils, the values of the viscous interaction coefficient of more than 100 kN⋅s/m2, may lead to complete attenuation of the bursts at the wave front in the pipeline.
Development of hardware and a system for analyzing energy parameters based on simulation in SimInTech
Authors: Shchemeleva Y B , Sokolov A A , Labazanova S H
Published: June 2022

The work is devoted to the issue of improving the efficiency of information systems in the field of energy, in particular, specialized systems in the field of data analysis and processing, designed for operational processing of information with its subsequent visualization, analysis and decision-making on the management of energy parameters of technological equipment, based on the developed ranking block information on monitored electrical power parameters using SimInTech software.
Mathematical modeling in the organization of the production process of leaching metals
Authors: Kondratyev Yu I , Sokolova O A , Arhipov P V
Published: June 2022

The following will describe the process of how you can use mathematical modeling to organize the production of metal leaching. Mathematical models and results of computational experiments are presented. The results of studying the thickness of films of sulfuric acid-chloride solutions containing the addition of surfactants surface-active substance (SAS), which are formed when they pour out onto a frosted glass surface as a model of the surface of a piece of ore, are presented. A mathematical model how the film thickness changes depending on the feed rate of the solution and its composition, as well as on the angle of inclination of the glass surface has been determined. Underground leaching of metals from ores stimulates the search for ways and means of intensifying the process. Due to the addition of a surfactant, the leaching process is accelerated, since the thickness of the films of leaching solutions flowing over the surface of ore minerals decreases. This direction is relevant in modern science, and research in this direction the growth of indicators allows the national economy to improve and helps to improve and increase knowledge for further development of the metallurgical industry in Russia The article also discusses the results of studies on the electrochemical leaching of metals from polymetallic ore by sulfuric acid-chloride solutions with the addition of a surfactant with asymmetric current pulses. Mathematical models of the dependence of leaching indicators on the density and duration of the flow of direct and reverse polarity are presented. For ease of perception and better visualization, a table was compiled, which reflects the results of comparative analysis to assess the further possibility of processing secondary raw materials.
Indicators of the effectiveness of the use of automation systems (SA) to support infocommunications services
Authors: Khasambiev I V , Vlasova O V
Published: June 2022

Administration of communication networks, according to the Law “On Communication”, is a set of organizational and technical measures aimed at ensuring the trouble-free and coordinated functioning of the communication network. Including traffic regulation, monitoring and control of the state of network elements, transport network channels and interactions of nodes, as well as managing the operation of applications and the provision of new infocommunication services. In this regard, this work is devoted to the study of the topic Indicators of the effectiveness of the use of automation systems to support infocommunications services
Justification of the methods of material and technical maintenance and repair of agricultural machines
Authors: Toigambayev S , Martinova N , Shavazov K , Telovov N
Published: June 2022

This work substantiates the rational structure of the repair and maintenance base of agricultural machinery, methods for determining the needs for material and technical means, taking into account the appropriate proportions between the links of the repair network. The maintenance and restoration of the operability of tractors and other agricultural machines in sufficient limits is ensured, as is known, with the help of a system of maintenance and repair, which provides for the implementation of preventive maintenance operations and the conduct of routine and major repairs of machines in a planned manner. The established system of maintenance and repair, the creation of a material and technical basis for its implementation, as well as a continuous process of improving the qualifications of machine operators and repair personnel, contribute to the effective use of equipment in agriculture. At the same time, there are significant disadvantages in the use of tractors and agricultural machines. The analysis of the results of numerous studies of VIMa, ChIMESXa and other organizations made it possible to identify and systematize the loss of time due to machine downtime. In particular, machine downtime for regulated maintenance is 10-15% of the shift time, for technical malfunctions - from 5-8% for plowing, up to 30% for harvesting crops. The volume of work on the repair of cars in the country as a whole is more than 2 times higher than the standard. The efficiency of maintenance and repair of machines largely depends on the level of the material and technical base of these works - the availability of modern equipment and tooling, industrial buildings, warehouses, and other structures, inventories, means of transport and communications.
Mathematical modeling of energy consumption in the production of hydrogen
Authors: Klyuev R V , Guzueva E R , Kunitsyn A G
Published: June 2022

The article discusses the technological process of hydrogen production at metallurgy. Mathematical models of the dependence of power consumption and specific consumption depending on various parameters have been obtained, which make it possible to calculate and predict. In the electrolyzer, the change in the component of the specific power consumption by the amount of potassium dichromate (chromium peak) over time is analyzed. Therefore, the analysis of the dependence of the specific power consumption in time was carried out directly on the basis of the results of an experimental study of the dependence of the change in time of the voltage on the electrolyzer when the electrolyzer was loaded with chromium peak. The most important issue of reducing electricity consumption due to the use of a gas holder in the mode of consumer-regulator has been investigated. Controlling the level of deviations in power consumption (±2%) in comparison with the normative (±5%) allows increasing the margin of "safety" in terms of load regulation time, reducing the likelihood of it going beyond the normative level and, accordingly, reducing the payment for deviations in the volume of electrical energy consumption.
Methodological support for increasing the technological potential in industry according to technological potential level and cyclical development
Authors: Sokolov A A , Samonova K V , Umarkhadzhiev M-Kh. R
Published: June 2022

The article discusses the issues of increasing the level of technological potential on the example of the Russian economy in the form of targeted state intervention during the implementation of import substitution. In the paper, the increase in technological capabilities is investigated taking into account the life cycle of the industry. The practical application of methods for assessing the level and vector of technological potential, as well as a dynamic model of organizational decision-making, is displayed.
Particle Image Velocimetry measurements in a turbulent channel flow laden with elongated particles
Authors: Capone Alessandro , Felice Fabio Di , Pereira Francisco Alves
Published: June 2022

Particle Image Velocimetry is employed to investigate the turbulence modulation induced by dispersed elongated, rod-like particles in a turbulent channel flow. Particles with two different aspect ratios AR=40,80 are tested, at a volume fraction of 10-5. Carrier flow velocimetry data and distribution and orientation data of dispersed particles are obtained by an ad-hoc single-camera phase-discrimination technique. Carrier flow data shows that in the near-wall region turbulence modulation by particle occurrs as well as a decrease of average streamwise velocity. Analysis of conditional probability density function of particles location reveals that particles locations statistically match flow regions with instantaneous low vorticity and high streamwise velocity, in particular in the near-wall region.
Estimation of Equivalent Conicity from Contactless Measurements of Wheel and Rail Profiles
Authors: Pugi L. , Bocciolini L. , Piccioli F. , Massini D. , Cherici G. , Lo Scalzo L.
Published: June 2022

Measurement of Equivalent Conicity is quite important index to properly evaluate geometric quality of rails and wheels. The way in which this index is evaluated is evaluated is described by the standard EN 15302 from online contactless measurement of rail profiles performed by a dedicated measurement coach. The numerical treatment of large amount of data derived by the acquisition of a huge number of measured rail profiles should be performed with great accuracy but also with a great numerical efficiency to assure a near to real time evaluation of performed analysis. In this work authors describe an efficient procedure developed using open-source software that has been developed to meet accuracy, efficiency, and portability specifications. Paper investigates how different integration and smoothing should affect efficiency and accuracy of performed operations. Proposed approach is first validated on numerical synthetic inputs and then validated on experimental data, also comparing performances of the proposed software with a commercial one. Results are encouraging, demonstrating the feasibility of the proposed approach for the realization of flexible and efficient tools for Real-Time implementation of the estimation of equivalent conicity for railway applications.
Potentially Automated Mechanical Characterization of Metal Components by Means of Hardness Test Complemented by Non-Contact 3D Measurement
Authors: Bolzon Gabriella
Published: June 2022

Metal structures and infrastructures subjected to demanding working conditions must be carefully monitored throughout their entire life cycle. In fact, high operating temperatures and interaction with aggressive environments produce significant variation of the mechanical characteristics of the materials, and eventually compromise the overall structural integrity. The evolution over time of metal properties can be determined in fast, cheap and non-destructive manner by hardness tests, processing the data that describe the geometry of the residual deformation left on the indented surface. The required equipment can be mounted on the arms of collaborative robots, and/or on frames that move on wheels or rails, to detect the material characteristics automatically, over large distances and with high spatial resolution. The reliability of such a diagnostic approach depends on the accuracy of the information that can be collected, in situ, by portable devices that perform 3D contactless measurement, and on the robustness of the data filtering and interpretation procedures. These issues are illustrated in this contribution.
Digital Image Correlation analysis on the bone displacement during split crest: an ex vivo study
Authors: Lugas A T , Terzini M , Stacchi C , Lombardi T , Di Donato D , Baldi D , Schierano G , Bignardi C
Published: June 2022

The split crest is an established surgical technique for horizontal bone augmentation. It allows to place implants of adequate diameter in sites where the bone would be too thin for the implantation. In this study, two split crest techniques (using threaded bone expanders or ultrasonic bone surgery) were performed ex vivo on bovine ribs, and dental implants were then inserted in the so prepared implantation sites. Digital image correlation was used to measure the bone external surface displacement throughout the surgical procedures. Both techniques provided an adequate bone volume for implant insertion, and no significant differences were highlighted regarding the displacement. However, bone accidental fracture only occurred during split crest with threaded bone expanders, suggesting differences in the internal strain distribution induced by the two techniques.
Plastic Flow Characteristics of Micro Single-Crystal Copper
Authors: Li Sheng , Su Ting , Yan Yabin
Published: June 2022

In order to study the plastic flow characteristics of micro single-crystal Cu, an in-situ uniaxial loading test was carried out. The slip direction of the test is determined by the Schmidt factor, which is at 1μm~4μm. Within the micropillar size range, the sample has an obvious size effect. This is essentially due to the continuous proliferation of dislocations in the micropillar flowing out of the surface. The smaller the size, the more difficult it is to store dislocations, and the easier dislocations flow out. Therefore, the yield stress significantly increases with the increment of sample diameter. This study provides guidance for the reliability evaluation of microscale components based on the single-crystal Cu.
Axial segragation in 3D rotating drums with spherical particles: Experiments
Authors: Tang Linglong
Published: June 2022

Despite the wide research of powder and solid mixing in science and industry, a majority of researches focus on numerical simulation. Theory on the actual mixing of solid particles in 3D rotary drums is needed. In this work, the axial segregation of binary spherical granular particle is studied experimentally in a 3D tumbler to find the effect of key outer parameters on the mixing results. Experiment results indicate the outer parameter-rotational speed will have significant effect on axial segregation and there is some kind of competition between axial segregation and radial segregation. In addition, The initial loading method has noting to do with axial segregation. These results will provide guidance for particle mixing in cylinder mixer.
Clusters and cooperatives as a tool of sustainable food security: a comparative analysis
Authors: Mindlin Yury , Novikov Mikhail , Ignatyeva Olga
Published: June 2022

The present model of development of the Russian agriculture, characterized by domination of large agri-food companies, creates threats for sustainable development of small agricultural business (local and family farms). Potential disappearance of these small businesses from the market would undermine the sustainability of the Russian agriculture and the food security of Russian Federation. In order to survive in this unfavorable environment, small business should combine their resources, participate in agri-food value chains and get access to Russian and global food market. The goal of the present paper is to identify potential strategies of development of small agricultural business within different models of cooperation. The paper contains a detailed analysis of key features of clusters and cooperatives. It is demonstrated that clusters as flexible structures have a higher potential of resource accumulation thanks to absence of limitations for potential members. Clusters also ensure trans-border cooperation. All these features are absent in agricultural cooperatives. Due to these facts clusters should be preferred to cooperatives as a tool of strategic development of small agricultural business. However cooperatives can be used as an additional tool. Cooperatives can participate in clusters. These conclusions constitute the contribution of the present paper for practice. In addition to this recommendation for selection of strategies of small business development, the comparative analysis of clusters and cooperatives helped to identify the key distinctive features of clusters as institutional structures. Knowledge of these features may be useful for analysis of cluster development. This result is the theoretical contribution of the present paper.
Inverse design of programmable optical frequency comb using deep learning
Authors: Ma Yunjie , Li Peili , Shi Weihua
Published: June 2022

Optical frequency comb (OFC) has important applications in measurement, communication, military and other fields. Usually, OFC needs to be designed according to different applications. However, the existing methods to design the operating parameters of the OFC generators are time-consuming, inefficient, and difficult to achieve optimal results. In this paper, a novel method of inversely designing OFC using deep learning, which is real-time and can improve the performance of the generated OFC, is proposed and applied to an OFC generator based on a single dual-drive Mach–Zehnder modulator. In this method, according to the required target OFC, the trained neural network can be used to inversely design the corresponding parameters. Using this inverse design method, the generated OFC not only is highly consistent with the target OFC, but also has the programmability of comb-line number, comb-line power, side mode suppression ratio, and comb spacing. Moreover, the proposed method can be utilized for more complicated OFC generator, and is an inspiration for efficient design of OFC.
The Future of Causal Inference
Authors: Mitra Nandita , Roy Jason , Small Dylan
Published: June 2022

The past several decades have seen exponential growth in causal inference approaches and their applications. In this commentary, we provide our top-10 list of emerging and exciting areas of research in causal inference. These include methods for high-dimensional data and precision medicine, causal machine learning, causal discovery, and others. These methods are not meant to be an exhaustive list; instead, we hope that this list will serve as a springboard for stimulating the development of new research.
Effect of Schooling on Anemia and Nutritional Status Among Women: A Natural Experiment in Ethiopia
Authors: Muchomba Felix M
Published: June 2022

This study estimates the effect of length of schooling on anemia and nutritional status and evaluates the cost-effectiveness of primary schooling as an anemia intervention for women of childbearing age in Ethiopia. In 1994–1995, Ethiopia abolished primary school tuition fees and embarked on a large-scale educational investment program, which increased primary school enrollment and retention. An instrumented regression-discontinuity design was used to examine the effect on anemia risk and body mass index (BMI) of an increase in length of schooling resulting from the reforms, as a natural experiment. Anemia and BMI biomarkers and demographic data for 13,984 women were obtained from the 2011 and 2016 Ethiopia Demographic and Health Surveys, with the 2019 Mini Demographic and Health Survey used for robustness checks. Results indicate that each additional year of schooling reduced anemia risk by 3 percentage points (9.2%–11.2% reduction) and increased BMI (weight (kg)/height (m)2) by 0.26–0.42. Primary education was cost-effective—based on World Health Organization cost-effectiveness thresholds—as an anemia intervention, with a cost per anemia case averted of US$1,654. The findings suggest that investment in education reduces anemia risk later in life.
Use of Cosmetic Facial Injectables After Facial Aesthetic Surgery
Authors: Talwar Ankoor A , Shulkin Jared M , Hitchner Michaela , McAuliffe Phoebe B , Desai Abhishek A , Broach Robyn B , Percec Ivona
Published: June 2022

Background

Over the last 2 decades, both invasive and minimally invasive aesthetic procedures have proliferated. Aesthetic surgeons often recommend injectable treatments after cosmetic facial surgery for multiple reasons. However, literature is lacking on how cosmetic surgery affects postoperative facial injectable use.

Objectives

The aim of this study was to identify predictors of facial injectable use after cosmetic facial surgery.

Methods

All adult patients operated on by a single surgeon between 2013 and 2021 were retrospectively reviewed. Patients who had any of the following cosmetic facial surgeries were included: rhytidectomy, blepharoplasty, rhinoplasty, or genioplasty. Patient demographics, clinical history, intraoperative factors, and use of cosmetic facial injectables (neurotoxin, facial fillers, deoxycholic acid, poly-l-lactic acid) were recorded.

Results

A total of 227 patients who underwent facial cosmetic surgery were reviewed, of whom 158 were included. Of these, 89 patients had rhytidectomy (56.3%), 112 had blepharoplasty (70.9%), 28 had rhinoplasty (17.7%), and 7 had genioplasty (4.4%). Injectables were administered to 44.3% of patients after their surgery (n = 73), compared with only 17.7% before surgery (n = 28) (P < 0.001). The most common postoperative injectables were neurotoxins (48.5%) and facial fillers (46.0%), followed by deoxycholic acid (2.7%) and poly-l-lactic acid (2.7%). Multivariate regression revealed factors positively correlated with future injectable use were index blepharoplasty or rhinoplasty, and history of preoperative neurotoxin injection (P < 0.05).

Conclusions

Cosmetic facial injectables are an important consideration in achieving and maintaining optimal facial aesthetics. Their use, especially neurotoxins and facial fillers, has increased among patients postoperatively. These results highlight the contribution of injectable procedures in the context of multidimensional care for augmenting facial aesthetics.

Level of Evidence: 4
Outlier detection for multi-network data
Authors: Dey Pritam , Zhang Zhengwu , Dunson David B
Published: June 2022

Motivation

It has become routine in neuroscience studies to measure brain networks for different individuals using neuroimaging. These networks are typically expressed as adjacency matrices, with each cell containing a summary of connectivity between a pair of brain regions. There is an emerging statistical literature describing methods for the analysis of such multi-network data in which nodes are common across networks but the edges vary. However, there has been essentially no consideration of the important problem of outlier detection. In particular, for certain subjects, the neuroimaging data are so poor quality that the network cannot be reliably reconstructed. For such subjects, the resulting adjacency matrix may be mostly zero or exhibit a bizarre pattern not consistent with a functioning brain. These outlying networks may serve as influential points, contaminating subsequent statistical analyses. We propose a simple Outlier DetectIon for Networks (ODIN) method relying on an influence measure under a hierarchical generalized linear model for the adjacency matrices. An efficient computational algorithm is described, and ODIN is illustrated through simulations and an application to data from the UK Biobank.

Results

ODIN was successful in identifying moderate to extreme outliers. Removing such outliers can significantly change inferences in downstream applications.

Availability and implementation

ODIN has been implemented in both Python and R and these implementations along with other code are publicly available at github.com/pritamdey/ODIN-python and github.com/pritamdey/ODIN-r, respectively.

Supplementary information

Supplementary data are available at Bioinformatics online.
Multiple Blind Signature for e-Voting and e-Cash
Authors: Harn Lein , Hsu Chingfang , Xia Zhe , Li Zixuan
Published: June 2022

In this paper, we propose a new cryptographic primitive, called multiple blind signature (MBS), which is designed based on the integration of both normal blind signature scheme and dual signature. The major difference between a normal blind signature and an MBS is that using a normal blind signature, only one message, $m$, can be verified, but using an MBS, any subset, ${M}^{\prime }$, of multiple messages in a set, $M$, where ${M}^{\prime}{\subseteq} M$, can be verified. With this additional property, we will show that MBS is especially suitable for e-voting and e-cash applications. In other words, we classify these processes in two applications into two phases, on-line and off-line phases. One unique property of this design is that most time-consuming computation and interaction can be performed in advance in off-line phase. There is no cost of computation and interaction in the online phase.
Matched field processing accounting for complex Earth structure: method and review
Authors: Schippkus Sven , Hadziioannou Céline
Published: June 2022

Matched field processing (MFP) is a technique to locate the source of a recorded wavefield. It is the generalization of plane-wave beamforming, allowing for curved wave fronts. In the standard approach to MFP, simple analytical Green’s functions are used as synthetic wavefields that the recorded wavefields are matched against. We introduce an advancement of MFP by utilizing Green’s functions computed numerically for Earth structure as synthetic wavefields. This allows in principle to incorporate the full complexity of elastic wave propagation without further manual considerations, and through that provide more precise estimates of the recorded wavefield’s origin. We call this approach numerical MFP (nMFP). To demonstrate the applicability and potential of nMFP, we present two real data examples, one for an earthquake in Southern California, and one for secondary microseism activity in the Northeastern Atlantic and Mediterranean Sea. In addition, we explore and clarify connections between localization approaches for the ambient seismic field, real world limitations, and identify key areas for future developments. To increase the adoption of MFP in the seismological community, tutorial code is provided.
Response to a commentary by Barr (2022) on Edoka and Stacey (2020) estimating a cost-effectiveness threshold for healthcare decision-making in South Africa
Authors: Edoka Ijeoma , Stacey Nicholas
Published: June 2022

Methodological issues pose significant challenges to estimating marginal cost per unit of health. In this commentary, we revisit these challenges and respond to a recent commentary on the validity of previously estimated marginal cost per unit of health in South Africa.
The Performance of the Rutgeerts Score, SES-CD, and MM-SES-CD for Prediction of Postoperative Clinical Recurrence in Crohn’s Disease
Authors: Narula Neeraj , Wong Emily C L , Dulai Parambir S , Marshall John K , Jairath Vipul , Reinisch Walter
Published: June 2022

Background

We compared the Simple Endoscopic Score for Crohn’s Disease (SES-CD) and Modified Multiplied SES-CD (MM-SES-CD) scores with the Rutgeerts score for predicting clinical recurrence (CR) of postoperative Crohn’s disease (CD).

Methods

This post hoc analysis of the prospective, multicenter, randomized, double-blind, placebo-controlled trial comparing remicade and placebo in the prevention of recurrence in Crohn’s disease patients undergoing surgical resection who are at an increased risk of recurrence (PREVENT) study used receiver operating characteristic curve analyses to compare the Rutgeerts, SES-CD, and MM-SES-CD scores at week 76 for subsequent CR by week 104 in 208 participants. Multivariate logistic regression models evaluated cutoffs for the odds of experiencing CR by week 104, after adjustment for confounders. CR was defined as Crohn’s Disease Activity Index score ≥200 and ≥70-point increase from baseline (or development of fistulas, abscesses, or treatment failure) and endoscopic recurrence by week 104, defined as Rutgeerts score ≥i2.

Results

The week 76 Rutgeerts score predicted CR by week 104 with fair accuracy (area under the receiver-operating characteristic curve [AUC], 0.74; 95% confidence interval [CI], 0.65-0.83), which was similar to the SES-CD ileum score (AUC, 0.72; 95% CI, 0.64-0.80) and the MM-SES-CD ileum score (AUC, 0.72; 95% CI, 0.63-0.80). Compared with cutoffs by the other scores, the MM-SES-CD total score ≥26 at week 76 had the highest odds ratio to predict CR by week 104. Patients with a week 76 MM-SES-CD total score ≥26 were 4.41 times (95% CI, 2.06-9.43, P < .001) more likely to have CR by week 104 compared with those with an MM-SES-CD total score <26.

Conclusions

The SES-CD and MM-SES-CD perform similarly to the Rutgeerts score for predicting subsequent CR of postoperative CD. The MM-SES-CD threshold of ≥26 was predictive of postoperative CR. Clinicians and trialists could consider using the SES-CD or MM-SES-CD to assess postoperative CD given their ability to capture colonic disease recurrence and predict CR.
De Novo Pediatric Ulcerative Colitis Triggered by SARS-CoV-2 Infection: a Tale of 2 Sisters
Authors: Preziosi Nicholas A , Rizvi Areeba H , Feerick John D , Mandelia Chetan
Published: June 2022

Lay Summary

We present a report of 2 sisters who developed acute onset hematochezia concurrently with SARS-CoV-2 infection. One patient recovered completely, whereas the sibling developed chronic symptoms leading to a diagnosis of ulcerative colitis requiring biologic therapy.