Incorrect application of the epicycloid equation to the planetary mechanism of the cotton harvester

The content of the paper is based on the mathematical construction of the parametric equation of the epi- and hypocycloid curve described by a circle point. The purpose of the paper is to present the equations of epi- and hypocycloids in a parametric form in relation to the epi- and hypocyclic mechanism in a form convenient for calculation; to present the results of computational experiments on constructing phase trajectories of motion of a moving point of an epi- and hypocycloid. A detailed analysis of the analytical model of epi- and hypocycloids circumscribed by a point of a circle (on a moving circle) has been made. The equations of epi- and hypocycloids are presented in parametric form as applied to the epi- and hypocyclic mechanism in a form convenient for calculation. The results of studies on the construction of phase trajectories of a moving point of an epi- and hypocycloid with an analysis of the obtained curves are presented. The analytical model of epi- and hypocycloids is of practical importance, since it allows designing geared linkage mechanisms formed by attaching two-wire Assur group of various modifications to the planetary mechanism, as the primary mechanism.

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Influence of inaccuracies and measurement errors on frequency of uncoupling of cars for unscheduled repairs on the railways of the Republic of Uzbekistan

Proceedings of Petersburg Transport University ◽

10.20295/1815-588x-2021-4-507-514 ◽

2021 ◽

Vol 2021 (4) ◽

pp. 507-514

Author(s):

Aziz B. GAYIPOV ◽

Keyword(s):

Initial Data ◽

Detailed Analysis ◽

Measurement Errors ◽

Practical Importance ◽

The Republic ◽

The Impact

Objective: Considering the impact of inaccuracy and errors in measuring the thickness of the fl ange of wheelsets on the frequency of uncoupling for unscheduled repairs on the railways of the Republic of Uzbekistan. Conducting an analysis of the impact of uncoupling freight cars for unscheduled wheelset malfunctions repairs. Methods: Methods of combinatorial and statistical analyzes of the initial data are used. Results: A detailed analysis of car uncoupling for unscheduled repairs on the railways of Uzbekistan has been carried out. The probabilities of car uncoupling operation in TR-2 (current repair) due to the “thin fl angeˮ malfunction have been determined. The infl uence of inaccuracies and measurement errors on the frequency of uncoupling of cars for such a repair is estimated. Practical importance: The results obtained contribute to the deepening of knowledge about the possibility of the infl uence of inaccuracies and errors in measuring the thickness of the fl ange of wheelsets on the performance of cars.

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Mathematical modeling and design

10.12737/textbook_59688803c3cb35.15568286 ◽

2017 ◽

Author(s):

Кравченко ◽

Igor Kravchenko

Keyword(s):

Mathematical Modeling ◽

Linear Programming ◽

Mathematical Models ◽

Detailed Analysis ◽

Crop Production ◽

Practical Importance ◽

Mathematical Statistics ◽

Agricultural Industry ◽

Production Processes

In this education guidance general concepts of mathematical modeling and economic-mathematical in particular are considered, detailed analysis of step-by-step creation and the analysis of a number of the economic-mathematical models having the practical importance for forecasting and effective optimization of various production processes in crop production is given. In a theoretical part the generalized analysis and classification of the methods and models applied in a research of economic units and processes in agricultural industry is given further practical examples of development of mathematical models on the basis of methods of linear programming and mathematical statistics are given. The education guidance is intended for masters of the directions 35.04.04 – Agronomics and 35.04.03 – Agrochemistry and agrology, studying discipline "Mathematical modeling and designing".

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Parathyroid gland before and after cisplatin treatment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128584 ◽

1987 ◽

Vol 45 ◽

pp. 860-861

Author(s):

S.K. Aggarwal ◽

J.M. Fadool

Keyword(s):

Parathyroid Gland ◽

Wistar Rats ◽

Antitumor Agent ◽

The Body ◽

Cross Linking ◽

Limiting Factor ◽

Hormonal Changes ◽

Primary Mechanism ◽

Before And After ◽

Dna Strands

Cisplatin (CDDP) a potent antitumor agent suffers from severe toxic side effects with nephrotoxicity being the major dose-limiting factor, The primary mechanism of its action has been proposed to be through its cross-linking DNA strands. It has also been shown to inactivate various transport enzymes and induce hypocalcemia and hypomagnesemia that may be the underlying cause for some of its toxicities. The present is an effort to study its influence on the parathyroid gland for any hormonal changes that control calcium levels in the body.Male Swiss Wistar rats (Crl: (WI) BR) weighing 200-300 g and of 60 days in age were injected (ip) with cisplatin (7mg/kg in normal saline). The controls received saline injections only. The animals were injected (iv) with calcium (0.5 ml of 10% calcium gluconate/day) and were killed by decapitation on day 1 through 5. Trunk blood was collected in heparinized tubes.

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Practical Importance of Spatial Resolution and Analytical Sensitivity in AEM X-ray Microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135769 ◽

1990 ◽

Vol 48 (2) ◽

pp. 432-433

Author(s):

J. Zhang ◽

D.B. Williams ◽

J.I. Goldstein

Keyword(s):

Spatial Resolution ◽

Practical Importance ◽

Beam Current ◽

Specimen Thickness ◽

Analytical Sensitivity ◽

Related Factors ◽

X Ray ◽

Probe Size ◽

Excitation Volume ◽

Two Parameters

Analytical sensitivity and spatial resolution are important and closely related factors in x-ray microanalysis using the AEM. Analytical sensitivity is the ability to distinguish, for a given element under given conditions, between two concentrations that are nearly equal. The analytical sensitivity is directly related to the number of x-ray counts collected and, therefore, to the probe current, specimen thickness and counting time. The spatial resolution in AEM analysis is determined by the probe size and beam broadening in the specimen. A finer probe and a thinner specimen give a higher spatial resolution. However, the resulting lower beam current and smaller X-ray excitation volume degrade analytical sensitivity. A compromise must be made between high spatial resolution and an acceptable analytical sensitivity. In this paper, we show the necessity of evaluating these two parameters in order to determine the low temperature Fe-Ni phase diagram.A Phillips EM400T AEM with an EDAX/TN2000 EDS/MCA system and a VG HB501 FEG STEM with a LINK AN10 EDS/MCA system were used.

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Contrasts of planar defects in reflection electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015085x ◽

1993 ◽

Vol 51 ◽

pp. 1004-1005

Author(s):

Feng Tsai ◽

J. M. Cowley

Keyword(s):

Electron Microscopy ◽

Surface Defects ◽

Practical Importance ◽

Theoretical Treatment ◽

Crystal Surfaces ◽

Planar Defects ◽

Surface Steps ◽

Surface Reconstructions ◽

Domain Boundaries ◽

Reflection Electron Microscopy

Reflection electron microscopy (REM) has been used to study surface defects such as surface steps, dislocations emerging on crystal surfaces, and surface reconstructions. However, only a few REM studies have been reported about the planar defects emerging on surfaces. The interaction of planar defects with surfaces may be of considerable practical importance but so far there seems to be only one relatively simple theoretical treatment of the REM contrast and very little experimental evidence to support its predications. Recently, intersections of both 90° and 180° ferroelectric domain boundaries with BaTiO3 crystal surfaces have been investigated by Tsai and Cowley with REM.The REM observations of several planar defects, such as stacking faults and domain boundaries have been continued by the present authors. All REM observations are performed on a JEM-2000FX transmission electron microscope. The sample preparations may be seen somewhere else. In REM, the incident electron beam strikes the surface of a crystal with a small glancing angle.

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Prosodic Impairment Associated With Traumatic Brain Injury

Perspectives on Neurophysiology and Neurogenic Speech and Language Disorders ◽

10.1044/nnsld19.3.97 ◽

2009 ◽

Vol 19 (3) ◽

pp. 97-102

Author(s):

Billy Irwin

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Detailed Analysis ◽

Acoustic Characteristics ◽

Individual Variations

Abstract Purpose: This article discusses impaired prosody production subsequent to traumatic brain injury (TBI). Prosody may affect naturalness and intelligibility of speech significantly, often for the long term, and TBI may result in a variety of impairments. Method: Intonation, rate, and stress production are discussed in terms of the perceptual, physiological, and acoustic characteristics associated with TBI. Results and Conclusions: All aspects of prosodic production are susceptible to the effects of damage resulting from TBI. There are commonly associated prosodic impairments; however, individual variations in specific aspects of prosody require detailed analysis.

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