scholarly journals Straightening of low-rigid cylindrical details. Part I. Justification of the type of loading and modes at transverse straightening

2019 ◽  
Vol 62 (7) ◽  
pp. 517-524 ◽  
Author(s):  
S. A. Zaides ◽  
Kuang Le Khong
Keyword(s):  
Extreme Values ◽  
Initial Deflection ◽  
Mathematical Apparatus ◽  
Flat Plates ◽  
Residual Tension ◽  
Different Types ◽  
Definition Of ◽  
Loading Type ◽  
Ansys Workbench

For straightening of low-rigid cylindrical details like shaft and axes different types of loadings are considered which form tension different in size and in distribution. As the perspective direction, it is possible to consider correction by a bend at the influence of the distributed loading with the subsequent hardening of a billet by superficial plastic deformation based on a cross cheesing of it by flat plates. Purpose of the work was to define tension of the billet at cross correction for the choice of more effective type of loading and processing rational modes. The mathematical apparatus was used based on laws of the theory of an elastoplastic solid and Ansys Workbench software package. Novelty is the research of effective methods of loading at cross correction of cylindrical details. As a result of analytical calculations, value of the residual tension providing correction of cylindrical details was determined. Residual tension necessary for correction of cylindrical details depends on an initial deflection, material and preparation rate. Tension of cylindrical details was defined depending on a type of the application of cross loadings. Bend tension for correction of a shaft at distributed loading is less, than tension from action of cross force. For correction of a shaft with a diameter of 10 mm, 200  mm long and an initial deflection of 0.5  mm it is necessary to create bend tension equal to about 370  MPa. An effective method of loading at cross correction of cylindrical details is the bend at influence of the distributed loading. The received extreme values of bend coefficients are from 5.3 to 5.5 for all cases of shaft rigidity at correction by cross bend at distributed loading with l/L relation equal to 0.8. The developed mathematical model gives quite reliable values of the residual tension providing correction of cylindrical details. The analytical dependence for determination of the size of general deflections and definition of an effective loading type can be recommended for practical use in production for achievement of precision accuracy of low-rigid details like shaft.

scholarly journals A New Test of Filterability for Unprocessed Wines Evaluation of the Enzyme Efficiency

2021 ◽  
Vol 10 (2) ◽  
pp. 55-66
Author(s):  
Amélie Vallet-Courbin ◽  
Soizic Lacampagne ◽  
Rose Marie Canal-Llauberes ◽  
Sigolène Mattalana Malzieu ◽  
Tihomir Kanev ◽  
...  
Keyword(s):  
Suspended Matter ◽  
Measurement Method ◽  
Membrane Filtration ◽  
Enzyme Treatment ◽  
Filtration Process ◽  
Enzyme Efficiency ◽  
Different Types ◽  
Definition Of ◽  
Selection Of

A new Test of Filterability has been developed. Measurements carried out with different types of wines indicate that the new filterability index is a useful tool for understanding and predicting the propensity to fouling of treated or untreated wines, e.g. with or without enzyme addition. The measurement method used in the Test of Filterability, requires only one type of membrane for all types of wine, and uses the same equipment as the traditional Fouling Index. Numerous trials have demonstrated that the filtration of wines is governed by standard blocking law. The definition of the new Test of Filterability, based on this filtration law, is proposed. The choice of membrane and the selection of the optimal pore size were based on the results of the experiments. Current methods used for the determination of fouling properties in wine filtration have been developed for the membrane filtration of small quantities of suspended matter. Enzyme treatment is a process often used in wine clarification. The new Test of Filterability indicates the best conditions for the filtration of all types of wines. The test is easy to implement and has been validated with various wines. This new Test of Filterability is an important tool for winemakers as it constitutes a simplified test of a wine's filterability. The new test may also be used to determine the filtration process that is best adapted to each wine while reducing the number of operations. The same approach may be adopted for the filtration of other liquids. 

On the Determination of the Centers of Twist and of Shear for Cylindrical Shell Beams

1972 ◽  
Vol 39 (4) ◽  
pp. 1098-1102 ◽  
Author(s):  
E. Reissner ◽  
W. T. Tsai
Keyword(s):  
Cylindrical Shell ◽  
Cross Section ◽  
Flat Plates ◽  
Influence Coefficients ◽  
Special Cases ◽  
Box Beams ◽  
Circular Cylindrical Shells ◽  
Definition Of ◽  
Open Cross Section

We consider the problem on the basis of a definition of the centers of shear and of twist in terms of influence coefficients for end-loaded cantilever beams. We determine the influence coefficients approximately by combining the Saint Venant torsion and flexure solutions with an appropriate version of the principle of minimum complementary energy. We apply this method, considering the beam as a cylindrical shell. We find among other things a formula for closed-cross-section shells which includes as special cases the strength-of-materials formula for open-cross-section shells, as well as a formula for variable-thickness flat plates. Problems of particular theoretical interest for which solutions are given concern rectangular box beams and circular cylindrical shells with circumferentially varying properties.

scholarly journals The complexity of DNA sequences. Different approaches and definitions

2020 ◽  
Vol 15 (2) ◽  
pp. 313-337
Author(s):  
Vladimir D. Gusev ◽  
Liubov A. Miroshnichenko
Keyword(s):  
Dna Sequences ◽  
Quantitative Characteristic ◽  
Low Complexity ◽  
Structural Features ◽  
General Definition ◽  
Symbolic Sequence ◽  
Different Types ◽  
Definition Of

An important quantitative characteristic of symbolic sequence (texts, strings) is complexity, which reflects at the intuitive level the degree of their "non-randomness". A.N. Kolmogorov formulated the most general definition of complexity. He proposed measuring the complexity of an object (symbolic sequence) by the length of the shortest descriptions by which this object can be uniquely reconstructed. Since there is no program guaranteed to search for the shortest description, in practice, various algorithmic approximations considered in this paper are used for this purpose. Along with definitions of complexity, suggesting the possibility of reconstruction a sequence from its "description", a number of measures are considered that do not imply such restoration. They are based on the calculation of some quantitative characteristics. Of interest is not only a quantitative assessment of complexity, but also the identification and classification of structural regularities that determine its specific value. In one form or another, they are expressed in the demonstration of repetition in the broadest sense. The considered measures of complexity are conventionally divided into statistical ones that take into account the frequency of occurrence of symbols or short “words” in the text, “dictionary” ones that estimate the number of different “subwords” and “structural” ones based on the identification of long repeating fragments of text and the determination of relationships between them. Most of the methods are designed for sequences of an arbitrary linguistic nature. The special attention paid to DNA sequences, reflected in the title of the article, is due to the importance of the object, manifestations of repetition of different types, and numerous examples of using the concept of complexity in solving problems of classification and evolution of various biological objects. Local structural features found in the sliding window mode in DNA sequences are of considerable interest, since zones of low complexity in the genomes of various organisms are often associated with the regulation of basic genetic processes.

The Estimation of the Thermal Properties of Refractory Materials According to the Temperatures Acceleration Curve at the Blast Furnace Blowing-In

2015 ◽  
Vol 1095 ◽  
pp. 476-482 ◽  
Author(s):  
A.N. Dmitriev ◽  
Maxim O. Zolotykh ◽  
Yury A. Chesnokov ◽  
Oleg Yu. Ivanov ◽  
Galina Yu. Vitkina
Keyword(s):  
Thermal Conductivity ◽  
Mathematical Model ◽  
Blast Furnace ◽  
Thermal Properties ◽  
Thermal Conductivity Coefficient ◽  
Refractory Materials ◽  
Different Types ◽  
Definition Of ◽  
The Mathematical Model

In a laying of a hearth it is usually used to ten different types of the flameproof materials. The characteristics of materials declared by the manufacturer can differ from the actual. For creation of the mathematical model [1, 2] temperatures distributions in a laying of the concrete furnace it is necessary to know thermal conductivity of materials of the specific parties used at construction of the furnace. Definition of the thermal conductivity coefficient allows adapt mathematical model for specific conditions of use. The technique of determination of thermal properties of refractory materials on the temperatures acceleration curve at blowing-in of the blast furnace is described.

scholarly journals Modern understanding of legal policy

2020 ◽  
pp. 97-104
Author(s):  
Danis Rifkatovich Khasanov
Keyword(s):  
Social Life ◽  
Science Research ◽  
Theoretical Understanding ◽  
Legal Policy ◽  
Scientific Methods ◽  
Different Types ◽  
General Scientific ◽  
Points Of View ◽  
Definition Of

This article is dedicated to the theoretical understanding of the problem of ambiguity of the concept of “legal policy” as a complicated phenomenon that has a substantial number of attributes, which connect it with multiple occurrences within the legal sphere of social life and outside it; as well as overcoming such ambiguity through analyzing the diversity of characteristics of legal policy presented in the definitions of modern authors , and formation of the unified definition on their basis that would serve as methodological framework for the research of legal policy in all branches of juridical science. Research methodology includes the general scientific methods, such as analysis, synthesis, comparison, generalization, classification, and systemic approach. The author analyzes different points of view of the Russian scholars on formation of the concept of legal policy; describes their specific features; makes an attempt of their systematization. The conclusion is made on the presence of two different types of approaches towards determination of the content of legal policy. The author highlights most substantial characteristic suitable for both approaches, and offers an original version of a unified definition of legal policy of the state.

scholarly journals Methods of Determination of Optimal Points of Radio Monitoring Means Placement

2021 ◽  
Vol 7 (5) ◽  
pp. 2001-2009
Author(s):  
Serhii Dupelych ◽  
◽  
Viktor Bovsunovskyi ◽  
Dmytro Dmytro akymets ◽  
Oleksandr Zhantalai ◽  
...  
Keyword(s):  
Monitoring System ◽  
Optimization Problem ◽  
Radio Sources ◽  
Mathematical Apparatus ◽  
Radio Monitoring ◽  
Monitoring Tools ◽  
Different Types ◽  
The Matrix

The effectiveness of the radio monitoring system depends on the correctness of determining the coordinates of the location of radio monitoring tools at the stage of planning their application. The decision on the choice of position for radio monitoring should consider the heterogeneity of the terrain in the area of tasks, the presence of natural and electronic interference, which can lead to deterioration of conditions for receiving signals from radio sources. The use of the known methods, techniques, and algorithms for the placement of radio monitoring tools does not fully consider the requirements mentioned above. This leads to a decrease in the effectiveness of radio monitoring in a particular area of performance. Therefore, the purpose of this article is to develop a methodology for spatial placement of radio monitoring to ensure the effectiveness of radio monitoring in a particular area of tasks, taking into account the heterogeneity of the terrain, as well as natural and artificial electronic interference. Determining the coordinates of radio monitoring facilities included in the radio monitoring system involves determining the allowable options for their placement in a particular area of tasks using the mathematical apparatus of the dense placement function and its hodograph and further thinning of the matrix of acceptable solutions based on restrictions. A distinctive feature of the proposed approach is the optimization problem of geometric design for radio monitoring of complex spatial forms. At the same time, the peculiarities of completing the radio monitoring system using different types are also taken into account. It is expedient to use the developed technique for the planning of application of the system of radio monitoring; formation of working decisions on the construction of the radio monitoring system; assessing the quality of decisions and the formation of alternatives; ensuring the adaptation of the structure of the radio monitoring system to changes in the situation under the influence of the enemy and the formation of new zones of electronic interference.

Determination of Fracture Behavior under Biaxial Loading of Kevlar 149

2015 ◽  
Vol 766-767 ◽  
pp. 1127-1132 ◽  
Author(s):  
S. Manigandan
Keyword(s):  
Fracture Behavior ◽  
Biaxial Loading ◽  
High Strength ◽  
Flame Resistance ◽  
Flat Plates ◽  
Standard Size ◽  
Effective Utilization ◽  
Different Types ◽  
Effective Reinforcement

The high crystalline fiber Kevlar 149 has a major industrial application and it is extensively used in aerospace industries due to its significant properties of ultra-high modulus, high strength, low density, high flame resistance. Kevlar 149 has an advantage over K 49, since it absorbs less moisture and has high compression strength [3]. In order to explore the vast application, this paper investigates the fracture response of the Kevlar material computationally, when they are subjected to biaxial loading in both tensile and compression. This loading is done to understand the response of the Kevlar how far they poor in compression and rich in tensile. The fiber induced with epoxy is to form as an effective reinforcement. Here the fiber taken as Kevlar 149 & K-49 and the epoxy resin. For easy understanding a sample of two flat plates is considered as a composite structure of standard size, which under goes the biaxial loading computationally using Abaqus/CAE. The pictorial data’s are taken from the post processing study and the data’s can be used to investigate the fracture mechanism of Kevlar 149 & K-49, under different types of strain loading. The output results of Kevlar 149 is compared with K-49 to analyze the behavior of fiber undergoes the biaxial loading both compressive and tensile and also the merits and effective utilization of K-149. It is suggested that this method can be applied to other type of composite materials.

Organic photochromism (IUPAC Technical Report)

2001 ◽  
Vol 73 (4) ◽  
pp. 639-665 ◽  
Author(s):  
Henri Bouas-Laurent ◽  
Heinz Dürr
Keyword(s):  
Optical Power ◽  
Chemical Degradation ◽  
Pericyclic Reactions ◽  
Two Photon ◽  
Technical Report ◽  
Different Types ◽  
Number Of Cycles ◽  
Definition Of ◽  
Optical Power Limiting

This technical report is a general introduction to organic photochromism. The definition of photochromism (PC) is given together with that of words with the ending "chromism", such as thermo-, electro-, piezo-, and tribochromism. Important concepts such as two-photon, gated, dual-mode PC and chirochromism are illustrated. The concept of fatigue (chemical degradation) and the determination of the main photochromic parameters (number of cycles, cyclability, half-life), and the spectrokinetic and mechanistic aspects are discussed. The main families of PC (organic compounds and biological receptors) are illustrated with chemical formulae, and the different types of reactions involved in the photochromic processes (pericyclic reactions, E/Z isomerization, group transfer, etc.) are listed. Some examples of applications to "optical power limiting" substances, photoresponsive materials, and photoswitchable biomaterials are considered.

scholarly journals Priorities in labor motivation of young agricultural scientists

2020 ◽  
Vol 203 ◽  
pp. 05015
Author(s):  
Yuri Pichugin ◽  
Yuri Lobeyko ◽  
Elena Zritneva ◽  
Valentine Ivashova ◽  
Bulat Pashtaev
Keyword(s):  
Agricultural Education ◽  
Practical Interest ◽  
Point Of View ◽  
Practical Significance ◽  
Mathematical Apparatus ◽  
Teaching Activities ◽  
Research And Teaching ◽  
Theoretical Significance ◽  
Definition Of

The article presents the results of the study of priorities in the field of labor motivation of young agricultural scientists. A review of publications on labor motivation shows that important areas of research are the definition of priorities among internal and external motives and their study in segmentation by age and spheres of activity. Therefore, the determination of the priorities of labor motivation of young agricultural scientists is of great scientific and practical interest. We studied the motives of effective research and teaching activities of young employees on the example of a sociological survey conducted on the basis of Stavropol State Agrarian University. Using SPSS Statistics (version 21) software package and a unique mathematical apparatus, the priorities of labor motivation of young agricultural scientists were established. From the point of view of theoretical significance, the presented materials make it possible to use the research algorithm in such situations. The practical significance of the research results lies in the formation of an information base for strategic management of personnel processes in organizations of agricultural education.

State Failure and the Political Violence Phenomenon: A Comparative Analysis of Iraq and Syria Cases

2016 ◽  
Vol 4 (2) ◽  
pp. 170 ◽  
Author(s):  
K. Eylem Özkaya Lassalle
Keyword(s):  
Cold War ◽  
Political Violence ◽  
State Failure ◽  
The Political ◽  
Collective Violence ◽  
Short Run ◽  
Definition Of ◽  
The Cold War

The concept of failed state came to the fore with the end of the Cold War, the collapse of the USSR and the disintegration of Yugoslavia. Political violence is central in these discussions on the definition of the concept or the determination of its dimensions (indicators). Specifically, the level of political violence, the type of political violence and intensity of political violence has been broached in the literature. An effective classification of political violence can lead us to a better understanding of state failure phenomenon. By using Tilly’s classification of collective violence which is based on extent of coordination among violent actors and salience of short-run damage, the role played by political violence in state failure can be understood clearly. In order to do this, two recent cases, Iraq and Syria will be examined.

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