scholarly journals FORMATION OF PACKINGS WITH THE HELP OF WINDING MACHINE WITH PERIODICAL SPEED BUMP OF THE WINDING-UP ROLLER

2020 ◽  
Vol 49 (3) ◽  
pp. 12-15
Author(s):  
P. N. Rudovskiy ◽  
S. G. Smirnova
Keyword(s):  
Mathematical Model ◽  
Cycle Duration ◽  
High Quality ◽  
Pressing Force ◽  
Periodic Law ◽  
The Difference ◽  
Winding Machine ◽  
Selection Of

For the formation of a high-quality package of cross winding on machines equipped with winding mechanisms with a frictional drive of the package, it is necessary to include special devices in their composition that provide a change in the speed of the yarn feeder or bobbin according to a periodic law with a cycle duration of at least six periods of the yarn feeder movement. Changing the speed of the bobbin can be provided by slipping it by a controlled amount. The amount of slip is determined by the appropriate selection of the winding shaft acceleration (deceleration) and the pressing force of the bobbin against the winding shaft. A mathematical model has been obtained that describes the change in the difference between the displacements of points on the surface of the bobbin and the winding shaft when the winding shaft is accelerated. It is shown that in this way it is possible to effectively eliminate defects in the winding structure in the form of bundles and ribbons.

scholarly journals DYNAMICS OF TRACTION DEVICE OF MINE SUSPENDED MONOREL ROAD

2020 ◽  
Vol 12 (3) ◽  
pp. 410-417
Author(s):  
Viktor GUTAREVICH ◽  
◽  
Marina KONDRATENKO ◽  
Keyword(s):  
Mathematical Model ◽  
Mechanical System ◽  
Structural Parameters ◽  
Low Frequency ◽  
Dynamic Loads ◽  
Pressing Force ◽  
Negative Effect ◽  
Traction Device ◽  
The Difference ◽  
Fatigue Fractures

During the operation of the mine suspension monorail track and traction device form a mechanical system experiencing high dynamic loads associated with implementation of traction and braking forces. Emerging dynamic loads lead to formation of elastic deformations and oscillations that cause vibrations, which leads to displacement of drive wheels and reduces the implementation of traction. The study of the dynamics of traction device is an important step in improving safety and reliability of monorail transport. The aim of the work is to study dynamics of a friction-type traction device moving along a suspended monorail to assess influence of parameters of the elements of device on the vibrations and nature of interaction of drive wheels with monorail. Research methods. Mathematical modeling of the oscillatory processes resulting from interaction of the running gear of the traction device with the monorail is used. Stages of research include drawing up a design diagram oscillations of drive wheels of the traction device interacting with the monorail, developing a mathematical model for the analysis of vibrations caused by moving loads, also assessing the influence of structural parameters of mechanical system under consideration on nature of oscillations. Research results. The developed mathematical model of friction-type traction device movement allows us to establish relationship between parameters of structural elements of its running gear and pressure mechanism, as well as nature of vibrations that arise. As a result, frequencies of the mechanical system under consideration and maximum deviations were found, which allows you to set optimal device parameters to increase traction and increase lifespan of monorail suspended roads. Findings. It was determined that the frequency range of vibration of drive wheels mainly corresponds to the mid-frequency local vibrations of 16–36 Hz. Increasing length of lever for fixing axles of wheels and reducing their radius leads to formation of low-frequency vibrations with a frequency of less than 15 Hz. When length of lever of drive wheels is more than 0.5 m, shoulder of the spring is more than 0.6 m and radius of drive wheels is less than 0.25 m, vibrations with frequencies below 5 Hz can occur. It was found that increasing the length of lever for securing spring increases the oscillation frequency of one drive wheel and reduces frequency of the other. The difference between these frequencies significantly affects changes in the pressure of the wheels against monorail. When difference between frequencies is more than 10–12 Hz, direction of load changes pulsed, with a maximum swing of 0.02 rad, which reduces formation of fatigue fractures of tire wheels, and moments of decrease and increase in pressing force have a negative effect on traction, leading to slippage of drive wheels. When difference between frequencies is less than 10–12 Hz, direction of the load changes sharply, with a maximum swing of 0.03 rad, which increases deformation and formation of fatigue fractures of tire wheels, and short moments of weakening and increase of pressing force, constituting 0.1–0.3 s does not have a significant negative effect on traction.

Development of methodology bases of the network mathematical models transportation and technological flows timber.

2017 ◽  
Vol 6 (2) ◽  
pp. 63-68
Author(s):  
Бурмистрова ◽  
Olga Burmistrova ◽  
Пильник ◽  
Yuliya Pilnik
Keyword(s):  
Mathematical Model ◽  
Quality Management ◽  
Mathematical Models ◽  
Transport Systems ◽  
Object Model ◽  
Optimal Solutions ◽  
Mechanical Modeling ◽  
High Quality ◽  
The Mathematical Model ◽  
Selection Of

The mathematical-mechanical modeling - is the study of complex transport systems (processes) through on-the structure and the research object model. Mathematical models allow a pre-selection of optimal solutions according to specific criteria. These scientifically based and are designed to help leaders in the development, validation and acceptance of efficient, high-quality management decisions in the forest complex. But it must be a pony-mother, that any solution obtained by calculating the mathematical model, optimal only for one or more criteria.

scholarly journals SEARCH FOR THE OPTIMAL SOLUTION FOR ASSIGNING SUBURBAN-URBAN TRAINS ON BRANCHED LINES ON EACH OF THE POSSIBLE ROUTES

T-Comm ◽  
2020 ◽  
Vol 14 (11) ◽  
pp. 39-45
Author(s):  
Vadim N. Shmal ◽  
◽  
Liliya R. Aysina ◽  
Keyword(s):  
Genetic Algorithm ◽  
Mathematical Model ◽  
Optimal Solution ◽  
Directed Search ◽  
Optimal Method ◽  
Source Data ◽  
On Line ◽  
The Difference ◽  
Traffic Organization ◽  
Selection Of

The article describes the problem of organizing train traffic on line with branches, analyzes possible separate routes on the "trunk" and "branch" sections, and brunched routes. The development of a mathematical model which consider the interests of passengers in a service provided and economic interest of passenger companies are elements of scientific novelty of presented researching. The insufficient disclosure in the existing theoretical base of the issues of train traffic organization on lines with branches confirms the relevance of the research. The deficit of clear requirements for the organization of such lines leads to empirical decisions when operating such facilities. Adhering to the goal of providing a comfortable service for passengers and taking into account economic aspects in the interests of suburban companies, the objective function is minimize the difference between the mileage of available seats (as a condition that reflects the interests of a commuter company) and the overcrowding of the train (as a criterion that ensures a comfortable ride for the passenger). The authors suggest using a genetic algorithm for solve this problem. Genetic algorithm is a tool that allows you to perform a directed search of competitive options. The article describes the method of applying the genetic algorithm, the formation of "parent" variants and "offspring" variants, compliance with a number of restrictions and ranking of offspring variants for the selection of the best "individuals". Before testing the proposed method on a real example, the authors make a preliminary analysis to identify possible shortcomings that require improvement. The possibility of using a mathematical model and a genetic algorithm to find the optimal (or close to optimal) option for organizing traffic on a line with branches is considered on an arbitrary example. The presented calculations can be performed in any analytical software package. In this research, the search for the optimal method to organize traffic on a line with branches was performed in the MS Excel product. Successful calculations on an arbitrary option using the proposed mathematical model and genetic algorithms (as a tool to determine the optimal option of movement), allows us to assume that calculations can be made based on real source data for suburban directions of railway junctions that have lines with branches.

scholarly journals High-quality reference genome sequences of two coconut cultivars provide insights into evolution of monocot chromosomes and differentiation of fiber content and plant height

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Shouchuang Wang ◽  
Yong Xiao ◽  
Zhi-Wei Zhou ◽  
Jiaqing Yuan ◽  
Hao Guo ◽  
...  
Keyword(s):  
Plant Height ◽  
Copy Number ◽  
Cellulose Synthesis ◽  
High Quality ◽  
Single Nucleotide Change ◽  
Gibberellin Metabolism ◽  
Omics Analysis ◽  
Evolutionary Trajectories ◽  
The Difference ◽  
Selection Of

Abstract Background Coconut is an important tropical oil and fruit crop whose evolutionary position renders it a fantastic species for the investigation of the evolution of monocot chromosomes and the subsequent differentiation of ancient plants. Results Here, we report the assembly and annotation of reference-grade genomes of Cn. tall and Cn. dwarf, whose genome sizes are 2.40 Gb and 2.39 Gb, respectively. The comparative analysis reveals that the two coconut subspecies diverge about 2–8 Mya while the conserved Arecaceae-specific whole-genome duplication (ω WGD) occurs approximately 47–53 Mya. It additionally allows us to reconstruct the ancestral karyotypes of the ten ancient monocot chromosomes and the evolutionary trajectories of the 16 modern coconut chromosomes. Fiber synthesis genes in Cn. tall, related to lignin and cellulose synthesis, are found at a higher copy number and expression level than dwarf coconuts. Integrated multi-omics analysis reveals that the difference in coconut plant height is the result of altered gibberellin metabolism, with both the GA20ox copy number and a single-nucleotide change in the promoter together leading to the difference in plant height between Cn. tall and Cn. dwarf. Conclusion We provide high-quality coconut genomes and reveal the genetic basis of trait differences between two coconuts through multi-omics analysis. We also reveal that the selection of plant height has been targeted for the same gene for millions of years, not only in natural selection of ancient plant as illustrated in coconut, but also for artificial selection in cultivated crops such as rice and maize.

scholarly journals EXPERIMENTAL STUDIES OF BENDING CHARACTERISTICS FOR SELECTION OF MODERN OF STIFFENING FABRICS

2021 ◽  
Vol 52 (2) ◽  
pp. 33-37
Author(s):  
Veronika V. Zamyshlyaeva ◽  
Tat’yana L. Akindinova
Keyword(s):  
Reference Data ◽  
Experimental Studies ◽  
Structure Stability ◽  
Technological Properties ◽  
Shape Stability ◽  
High Quality ◽  
Automated Method ◽  
Bending Process ◽  
The Difference ◽  
Selection Of

The article presents the results of studies of the bending characteristics of modern stiffening fabrics of different fibrous composition. The studies were carried out by an automated method that allows im-plementing a graphical record of the bending process and recovery after bending using specially developed software. The method allows determining not only standard, but also new bending characteristics. New quality indicators, which determine the ability of stiffening fabrics to be processed into high-quality stiffening pads and allow assessing the garment shape stability during operation, are proposed. The expediency of experimental evaluation of these indicators for the modern range of stiffening fabrics is established. The reference data on indicators of technological properties of stiffening fabrics allowing digitalising selection is given. A new algorithm for the rational choice of shape-stable fabrics is proposed, focused on new characteristics of bending – the structure stability coefficient and the difference in work.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

scholarly journals Age-dependency in mortality of Finnish family caregivers: a nationwide register-based study

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
T M Mikkola ◽  
H Kautiainen ◽  
M Mänty ◽  
M B von Bonsdorff ◽  
T Kröger ◽  
...  
Keyword(s):  
General Population ◽  
Family Caregivers ◽  
Family Caregiver ◽  
Causes Of Death ◽  
Lower Mortality ◽  
All Cause Mortality ◽  
The Difference ◽  
Caregiver Role ◽  
Selection Of

Abstract Purpose Mortality appears to be lower in family caregivers than in the general population. However, there is lack of knowledge whether the difference in mortality between family caregivers and the general population is dependent on age. The purpose of this study was to analyze all-cause mortality in relation to age in family caregivers and to study their cause-specific mortality using data from multiple Finnish national registers. Methods The data included all individuals, who received family caregiver's allowance in Finland in 2012 (n = 42 256, mean age 67 years, 71% women) and a control population matched for age, sex, and municipality of residence (n = 83 618). Information on dates and causes of death between 2012 and 2017 were obtained from the Finnish Causes of Death Register. Flexible parametric survival modeling and competing risk regression adjusted for socioeconomic status were used. Results The total follow-up time was 717 877 person-years. Family caregivers had lower all-cause mortality than the controls over the follow-up (8.1% vs. 11.6%) both among women (hazard ratio [HR]: 0.64, 95% CI: 0.61-0.68) and men (HR: 0.73, 95% CI: 0.70-0.77). Younger adult caregivers had equal or only slightly lower mortality than their controls, but after age 60, the difference increased markedly resulting in over 10% lower mortality in favor of the caregivers in the oldest age groups. Caregivers had lower mortality for all the causes of death studied, namely cardiovascular, cancer, neurological, external, respiratory, gastrointestinal and dementia than the controls. Of these, the lowest was the risk for dementia (subhazard ratio=0.29, 95%CI: 0.25-0.34). Conclusions Older family caregivers have lower mortality than the age-matched controls from the general population while younger caregivers have similar mortality to their peers. This age-dependent advantage in mortality is likely to reflect selection of healthier individuals into the family caregiver role. Key messages The difference in mortality between family caregivers and the age-matched general population varies considerably with age. Advantage in mortality observed in family caregiver studies is likely to reflect the selection of healthier individuals into the caregiver role, which underestimates the adverse effects of caregiving.

scholarly journals A microfluidic device enabling drug resistance analysis of leukemia cells via coupled dielectrophoretic detection and impedimetric counting

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yağmur Demircan Yalçın ◽  
Taylan Berkin Töral ◽  
Sertan Sukas ◽  
Ender Yıldırım ◽  
Özge Zorlu ◽  
...  
Keyword(s):  
Drug Resistance ◽  
K562 Cells ◽  
Leukemia Cells ◽  
Drug Resistant ◽  
Wild Type ◽  
Gene Expressions ◽  
Before And After ◽  
The Difference ◽  
Selection Of ◽  
Resistant Cells

AbstractWe report the development of a lab-on-a-chip system, that facilitates coupled dielectrophoretic detection (DEP-D) and impedimetric counting (IM-C), for investigating drug resistance in K562 and CCRF-CEM leukemia cells without (immuno) labeling. Two IM-C units were placed upstream and downstream of the DEP-D unit for enumeration, respectively, before and after the cells were treated in DEP-D unit, where the difference in cell count gave the total number of trapped cells based on their DEP characteristics. Conductivity of the running buffer was matched the conductivity of cytoplasm of wild type K562 and CCRF-CEM cells. Results showed that DEP responses of drug resistant and wild type K562 cells were statistically discriminative (at p = 0.05 level) at 200 mS/m buffer conductivity and at 8.6 MHz working frequency of DEP-D unit. For CCRF-CEM cells, conductivity and frequency values were 160 mS/m and 6.2 MHz, respectively. Our approach enabled discrimination of resistant cells in a group by setting up a threshold provided by the conductivity of running buffer. Subsequent selection of drug resistant cells can be applied to investigate variations in gene expressions and occurrence of mutations related to drug resistance.

Selection of high-quality sperm with thousands of parallel channels

Lab on a Chip ◽  
2021 ◽  
Author(s):  
Mohammad Simchi ◽  
Jason Riordon ◽  
Jae Bem You ◽  
Yihe Wang ◽  
Sa Xiao ◽  
...  
Keyword(s):  
Clinical Practice ◽  
High Selectivity ◽  
High Yield ◽  
Sperm Selection ◽  
High Quality ◽  
Parallel Channels ◽  
Selection Of

A 3D-structured sperm selection device is presented that achieves both high selectivity and high yield via thousands of parallel channels. The device significantly outperforms the best clinical practice by selecting ∼100 000 of higher-quality sperm.

scholarly journals Weightage Effect during Back-Calculation of Rock-Mass Quality from the Installed Tunnel Support in Rock-Mass Rating and Tunneling Quality Index System

2019 ◽  
Vol 9 (10) ◽  
pp. 2065 ◽  
Author(s):  
Jonguk Kim ◽  
Hafeezur Rehman ◽  
Wahid Ali ◽  
Abdul Muntaqim Naji ◽  
Hankyu Yoo
Keyword(s):  
Rock Mass ◽  
Quality Index ◽  
Rock Bolt ◽  
Rock Mass Rating ◽  
Rock Mass Quality ◽  
Back Calculation ◽  
The Difference ◽  
Bolt Spacing ◽  
Q System ◽  
Selection Of

In extensively used empirical rock-mass classification systems, the rock-mass rating (RMR) and tunneling quality index (Q) system, rock-mass quality, and tunnel span are used for the selection of rock bolt length and spacing and shotcrete thickness. In both systems, the rock bolt spacing and shotcrete thickness selection are based on the same principle, which is used for the back-calculation of the rock-mass quality. For back-calculation, there is no criterion for the selection of rock-bolt-spacing-based rock-mass quality weightage and shotcrete thickness along with tunnel-span-based rock-mass quality weightage. To determine this weightage effect during the back-calculation, five weightage cases are selected, explained through example, and applied using published data. In the RMR system, the weightage effect is expressed in terms of the difference between the calculated and back-calculated rock-mass quality in the two versions of RMR. In the Q system, the weightage effect is presented in plots of stress reduction factor versus relative block size. The results show that the weightage effect during back-calculation not only depends on the difference in rock-bolt-spacing-based rock-mass quality and shotcrete along with tunnel-span-based rock-mass quality, but also on their corresponding values.

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