scholarly journals Tension devices: mathematical modeling and applications in water transport

2021 ◽  
Vol 2131 (3) ◽  
pp. 032106
Author(s):  
R Fokin ◽  
M Abissova ◽  
A Atoyan
Keyword(s):  
Water Transport ◽  
Linear Equations ◽  
Analytical Calculation ◽  
Low Noise ◽  
Mathematical Methods ◽  
Conservation Of Energy ◽  
Ship Management ◽  
Systems Of Linear Equations ◽  
The Subject ◽  
The Moment

Abstract Tension devices -are throwing devices, the action of which is based on the elastic tension of the plates (shoulders), in fact, these are bows and crossbows. Currently, various types of bows and crossbows controlled by a single shooter are widely used in hunting and sports. In the ancient World, high-power crossbows were used as artillery, served by several warriors: ballistae, scorpions and others. In the paper, bows and crossbows of all currently common types are modeled using mathematical methods. This model, which is the subject of this paper, differs from similar ones, which actually model only traditional English bows. All these models have the main purpose of analytical calculation of the speed of the arrow at the moment of its separation from the bowstring. Our model uses the law of conservation of energy, considering only the initial and final moments of acceleration of the arrow. It identifies 2-4 implicit indicators that fully describe each type of tension devices. To obtain input data, 2-3 experimental shots are made with 1-2 parameters measured each time. As a result, the calculations are reduced to solving systems of linear equations and to calculations using formulas. The paper offers 3 areas of application of tension devices on water transport, firstly, ship management and its operational repair (for this purpose, analogues of ancient powerful crossbows are relevant), secondly, protection of the ship, cargo, anti-terrorism, and thirdly, physical education and sports for the crew and passengers. The use is due to their fire safety, power, low noise, a variety of types of projectiles.

scholarly journals IMPLEMENTATION OF THE ADVANCED LEARNING IN THE PROCESS OF FUNDAMENTAL MATHEMATICAL TRAINING OF BACHELORS IN THE FIELD OF ELECTRONICS AND TELECOMMUNICATION

2021 ◽  
Vol 1 (2) ◽  
pp. 81-87
Author(s):  
ALYONA ALYOA KOLOMIETS
Keyword(s):  
Linear Equations ◽  
Variational Calculus ◽  
Variable Coefficients ◽  
Mathematical Methods ◽  
First Semester ◽  
Technical Developments ◽  
Analysis And Synthesis ◽  
Norm Operator ◽  
The Moment ◽  
Independent Tasks

The article substantiates the expediency of the implementation of the advanced learning in the process of fundamental mathematical training of bachelors in the field of electronics and telecommunications. At the moment, the field requires mandatory (deep) knowledge of the main classical sections of mathematics, it is also important to acquaint students in higher mathematics with elements of modern mathematical theories, concepts that allow learners to better understand special courses in mathematics and relevant special disciplines. materials of mathematics, which are used in the modern mathematical models of technical developments. The aim of the article is to reveal the approaches to the concept of the advanced learning in the process of fundamental mathematical training of future bachelors in the field of electronics and telecommunications.The main methods that were implemented in the study of the problem of advanced learning were the analysis and synthesis of the scientific sources on the selected problem, observation, implementation of projects and evaluation of their results. It is offered (from the first semester) to introduce generalized concepts (norm, operator, etc.) in time, to acquaint with ideas of variational calculus, functional analysis, mathematical methods of research of linear equations with variable coefficients, theory of stochastic approximation, mathematical modelling. Then the future specialist will be able to comprehend the objects, which have been already developed by mathematicians but have not been used yet. Thus, a difficult topic or concept can be considered in advance in some connection with the currently studied material. For example, during the study of a function and the construction of its graph, along with the asymptote, students can be introduced to the approximation of the function, the concepts of interpolation and approximation. It is expedient to acquaint students with these problems more deeply during performance of independent tasks (consultations, the abstract, the report at conference, etc.).

scholarly journals SECTIONING OF HIGH DIMENSIONAL BANDED MATRICES

2014 ◽  
pp. 14-21
Author(s):  
Dmytro Fedasyuk ◽  
Pavlo Serdyuk ◽  
Yuriy Semchyshyn
Keyword(s):  
Linear Equations ◽  
Computing Time ◽  
Mathematical Physics ◽  
High Dimensional ◽  
Systems Of Equations ◽  
Algebraic Equations ◽  
Banded Matrices ◽  
Linear Algebraic Equations ◽  
Systems Of Linear Equations ◽  
The Subject

Solving high dimensional systems of linear algebraic equations is of use to many problems of mathematical physics, in particular, it is one of the main subgoals at solving systems of equations in partial derivatives. Distributed solving of high dimensional systems of linear equations allows to reduce computing time, especially in cases when these matrices can not be kept in one computer's RAM. The subject of this study is the search of optimal high dimensional matrices sectioning algorithms for distributed solving systems of linear algebraic equations.

On Some Properties of Semi-rings

2018 ◽  
pp. 35-50
Author(s):  
A. I. Belousov
Keyword(s):  
Linear Equations ◽  
Oriented Graph ◽  
Theoretical Computer Science ◽  
Alternative Methods ◽  
Main Role ◽  
Cost Matrix ◽  
Sequential Elimination ◽  
The Matrix ◽  
Systems Of Linear Equations ◽  
The Cost

The main objective of this paper is to prove a theorem according to which a method of successive elimination of unknowns in the solution of systems of linear equations in the semi-rings with iteration gives the really smallest solution of the system. The proof is based on the graph interpretation of the system and establishes a relationship between the method of sequential elimination of unknowns and the method for calculating a cost matrix of a labeled oriented graph using the method of sequential calculation of cost matrices following the paths of increasing ranks. Along with that, and in terms of preparing for the proof of the main theorem, we consider the following important properties of the closed semi-rings and semi-rings with iteration.We prove the properties of an infinite sum (a supremum of the sequence in natural ordering of an idempotent semi-ring). In particular, the proof of the continuity of the addition operation is much simpler than in the known issues, which is the basis for the well-known algorithm for solving a linear equation in a semi-ring with iteration.Next, we prove a theorem on the closeness of semi-rings with iteration with respect to solutions of the systems of linear equations. We also give a detailed proof of the theorem of the cost matrix of an oriented graph labeled above a semi-ring as an iteration of the matrix of arc labels.The concept of an automaton over a semi-ring is introduced, which, unlike the usual labeled oriented graph, has a distinguished "final" vertex with a zero out-degree.All of the foregoing provides a basis for the proof of the main theorem, in which the concept of an automaton over a semi-ring plays the main role.The article's results are scientifically and methodologically valuable. The proposed proof of the main theorem allows us to relate two alternative methods for calculating the cost matrix of a labeled oriented graph, and the proposed proofs of already known statements can be useful in presenting the elements of the theory of semi-rings that plays an important role in mathematical studies of students majoring in software technologies and theoretical computer science.

Crimes against marriage and family before Criminal Code 1968

2020 ◽  
Vol 15 (1-3) ◽  
pp. 44-59
Author(s):  
Lidia Peneva
Keyword(s):  
Criminal Code ◽  
Point Of View ◽  
Marriage And Family ◽  
Historical Method ◽  
Legal Method ◽  
The Subject ◽  
The Republic ◽  
Criminal Groups ◽  
The Moment ◽  
Structural Point

Crimes against marriage and family are a particular group of social relation­ships that the law has defended properly in view of the high public significance and value they enjoy. At the moment they are regulated in Chapter VI, Section I, of the specific part of the Penal Code the Repub­lic of Bulgaria. The subject matter of this Statement will, however, be the legisla­tive provisions concerning these criminal­ized acts in retrospect. The purpose of the study is to show by historical method and through the comparatively legal method the development of these criminal groups during the periods of various criminal laws in Bulgaria. This will also provide a basis for reflection on possible de lege ferenda proposals. This report from a structural point of view will be divided into three distinct points, marking each of the penal laws in the Republic of Bulgaria, which were in force before 1968.

scholarly journals Cartilage Injuries and Posttraumatic Osteoarthritis in the Wrist: A Review

Cartilage ◽  
2021 ◽  
pp. 194760352110219
Author(s):  
Jonny K. Andersson ◽  
Elisabet Hagert ◽  
Mats Brittberg
Keyword(s):  
Literature Review ◽  
Radius Fractures ◽  
Osteochondral Autograft ◽  
Posttraumatic Osteoarthritis ◽  
Osteochondral Repair ◽  
Chondrocyte Implantation ◽  
Cartilage Injuries ◽  
The Subject ◽  
The Moment ◽  
And Cartilage

Objective: Focal cartilage injuries, and posttraumatic osteoarthritis (OA) in the wrist are likely common and a cause of wrist pain. To estimate the incidence of cartilage lesions and to understand the pathomechanisms leading to wrist cartilage injuries and OA, a literature review on the subject was performed combined with a presentation of one of the authors’ own experience. Design: This study includes a literature review of the topic. As a comparison to the review findings, the observations of one of the authors’ consecutive 48 wrist arthroscopies, were assessed. PubMed, Scholar, and Cochrane databases were searched using the keywords “cartilage injury AND wrist AND treatment” and “wrist AND cartilage AND chondral AND osteochondral AND degenerative OA.” :Result A total of 11 articles, including 9 concerning chondral and osteochondral repair and treatment and 2 regarding posttraumatic OA, were retrieved. The cartilage repair treatments used in these articles were drilling, osteochondral autograft, juvenile articular cartilage allograft, and chondrocyte implantation. One article displayed concomitant cartilage injuries in displaced distal radius fractures in 32% of the patients. The review of our findings from a 1-year cohort of wrist arthroscopies showed 17% cartilage injuries. Conclusion: There is a lack of knowledge in current literature on cartilage injuries and treatment, as well as posttraumatic OA in the wrist. Cartilage injuries appear to be common, being found in 17% to 32% of all wrist arthroscopies after trauma, but no guidelines regarding conservative or surgical treatment can be recommended at the moment. Larger prospective comparative studies are needed.

scholarly journals A Globally Convergent Parallel SSLE Algorithm for Inequality Constrained Optimization

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Zhijun Luo ◽  
Lirong Wang
Keyword(s):  
Constrained Optimization ◽  
Optimization Problems ◽  
Linear Equations ◽  
Coefficient Matrix ◽  
Descent Direction ◽  
Constrained Optimization Problems ◽  
Inequality Constrained Optimization ◽  
Globally Convergent ◽  
Variable Distribution ◽  
Systems Of Linear Equations

A new parallel variable distribution algorithm based on interior point SSLE algorithm is proposed for solving inequality constrained optimization problems under the condition that the constraints are block-separable by the technology of sequential system of linear equation. Each iteration of this algorithm only needs to solve three systems of linear equations with the same coefficient matrix to obtain the descent direction. Furthermore, under certain conditions, the global convergence is achieved.

scholarly journals Disintegration process in disc crushers

2013 ◽  
Vol 59 (No. 3) ◽  
pp. 98-104 ◽  
Author(s):  
P. Vaculík ◽  
J. Maloun ◽  
L. Chládek ◽  
M. Přikryl
Keyword(s):  
Food Industry ◽  
Fractional Composition ◽  
Animal Feed ◽  
Raw Materials ◽  
Specific Energy Consumption ◽  
Low Noise ◽  
Main Process ◽  
Industrial Sectors ◽  
The Subject

Grinding or crushing hard raw materials is usually a primary operation which precedes the follow-up technological processes in a number of industrial sectors. A great variety of machines using different principles of fragmentation are employed in the technology of pulverization. The food industry uses roller mills, in which the main process is the shear grinding. In the animal feed industry impact machines known as hammer mills are often used. In recent years, mills have been employed that use their frontal edges for grinding or crushing during the rotation of one of two adjacent discs. The modern design disc machines used for grinding grain have resulted from long development and their operation has a relatively low noise level with reduced dust. The separation process that occurs in the gap between the active edges of the discs can be described as shear grinding and is currently the subject of attention which is focused on the specific energy consumption and fractional composition of the product of grinding.  

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