scholarly journals Fractal express methods evaluation of a breaking stress of concrete

2021 ◽  
Vol 1926 (1) ◽  
pp. 012023
Author(s):  
V M Volchuk ◽  
M A Kotov
2018 ◽  
pp. 157-164
Author(s):  
Sergei A. Alexandrov

The article is devoted to the creation of methods of accelerated lighting design of ski slopes for competitions with a television broadcast.


1989 ◽  
Vol 67 (3) ◽  
pp. 1063-1069 ◽  
Author(s):  
J. G. Tidball ◽  
M. Chan

Whole muscles loaded to failure frequently fail at or near myotendinous junctions. The present investigation was directed toward determining the breaking stress and failure site of intact and injured myotendinous junction preparations consisting of muscle cells dissected free from surrounding parallel structures but still attached to tendon collagen fibers. These tests show that the breaking stress for intact myotendinous units is 2.7 x 10(5) N/m2, expressed relative to cell cross-sectional area. Failure occurs immediately external to the junction membrane between the cell membrane and lamina densa of the basement membrane. Site and stress at failure are independent of strain and strain rate over a biologically relevant range. Breaking stress in the plane of the membrane, corrected for membrane folding, is 1.2 X 10(4) N/m2. This value is not significantly greater than stress at maximum isometric tension for these cells at these sarcomere lengths. After compression injury, cells fail within the compression site at significantly lower stress (1.9 X 10(5) N/m2). These findings suggest that, in muscle strain injuries that occur under conditions simulated here, failure occurs at myotendinous junctions unless the muscle has suffered previous compression injury leading to failure within the muscle.


1954 ◽  
Vol 11 (1) ◽  
pp. 66-70 ◽  
Author(s):  
J. A. GILLESPIE

SUMMARY 1. Paralysis, produced in young male rats by avulsion of peripheral nerves, resulted in a highly significant reduction in the total weight, ash weight, ash percentage, X-ray density and bending moment at the breaking point, of the bones of the affected limb. The breaking stress was significantly reduced, but Young's modulus of elasticity was unaltered. 2. Certain of these changes were modified by treatment with sex hormones. Both oestradiol and testosterone significantly reduced the difference between the bones of the normal and paralysed limbs in respect of total weight, ash weight and bending moment at the breaking point. 3. Treatment with oestradiol significantly increased both the ash percentage and Young's modulus of elasticity, the increase affecting equally the bones of the normal and paralysed limbs. Testosterone treatment did not significantly affect either of these properties, and neither hormone affected the breaking stress.


Author(s):  
Sergey Poliyevskiy ◽  
◽  
Galina Yamaletdinova ◽  
Elena Tsoy ◽  
Olga Grigorieva ◽  
...  

The importance of independent recreational practice for student-athletes is increasing in today’s environment. Therefore, it’s appropriate to prepare relevant recommendations for students undergoing heavy physical loads. The study was mainly aimed at the elaboration of the content of the Health Code for athlete students to render it as a component and method of implementing a self-health system. The theoretical and empirical methods applied during the implementation of the study were as follows: theoretic-comparative analysis, summarisation of relevant data from scientific-methodological publications on physiology, physical culture and sports, oriental medicine, observations, tests, mathematical statistics methods. The study used systemic and axiological approaches of a general scientific level of methodology. The Student-Athlete Health Code consists of recommendations for selecting the means of restoring performance and improving the functional state of the student-athlete body during an educational and training day. This is a set of personal health improvement rules prepared on the basis of modern scientifically reasoned data on hygiene and valeology. The Code’s programme material includes paramedical signs of the optimal functional condition and premorbid status; the authors’ recommendations on wellness devices, health monitoring tests and immune resistance; a brief description of wellness techniques, methods and recipes; express methods of reflexology and minimisation of fatigue and immunity stimulation; illustrative wellness informative tips and recommended literature. The solutions were tested in the educational and training process of students at the Russian State University of Physical Culture, Sport, Youth and Tourism, where 91.57 % of respondents mentioned benefits in their personal health after having followed the recommendations presented in the Health Code.


2019 ◽  
Vol 9 (2) ◽  
pp. 385-392
Author(s):  
A. S. Gur’ev ◽  
O. Yu. Shalatova ◽  
E. V. Rusanova ◽  
I. V. Vasilenko ◽  
A. Yu. Volkov

In this article data concerning coherent fluctuation nephelometry (CFN) use in clinical microbiology is presented. CFN-analyzer allows to solve two important problems – fast urine screening for bacteriuria within 2-4 hours and antibiotic susceptibility testing within 3-6 hours. Altogether more than 650 urine samples were tested, and the effectivity of CFN-analyzer for preliminary selection of samples for further analysis was shown. Method allows to detect negative samples, reducing the number of urine analyses by 70-80%. Simultaneous analysis of growth curves and concentration of microorganisms shows high sensitivity and specificity (95.2% и 96.9%). Also more than 250 antibiotic susceptibility tests were performed using CFN-analyzer to show its effectiveness for determination of resistant properties of both pure cultures and urine microflora without isolation of bacteria. The agreement with traditional methods was from 84% to 88%. The use of CFN-analyzer with express methods of identification of microorganisms (chromogenic nutrient broths or mass-spectrometry) allows to make full urine analysis within 1-2 days. In the future CFN-analyzer gives an opportunity to screen different human biological liquids, and finds an application for other microbiological tasks, including standardization and speeding-up in sanitary bacteriology.


2015 ◽  
Vol 4 (4) ◽  
pp. 121-126
Author(s):  
Tatiana Ivanovna Prozhorina ◽  
Semyon Aleksandrovitch Kurolap ◽  
Nadezhda Ivanovna Yakunina

Currently, the most popular are the express methods of quality control of the environment, which permit a relatively rapid assessment of ecological and geochemical situation. one such method is based on the use snow cover. snow has a high sorption capacity and is informative in identifying the object of man-made pollution of the urban environment. the paper presents the results of a study of the chemical composition of snow that had fallen in Voronezh during winter 2015. snow samples were taken in the period prior to snowmelt in various functional areas of the city. in order to identify the degree of technogenic impact on the various parts of the city of Voronezh, was made a comparative analysis of the results:аccording to the actual presence of pollutants in precipitation for the study of functional areas;сalculate the rate on the concentration of chemical elements for test samples of snow.according to the degree of mineralization and dust content in snow can be seen technogenic pressure on environment.therefore, a comparative analysis of the degree of contamination of snow in the various functional areas of the city were carried out for the two indicators of the chemical composition - the total mineralization and suspended particles(dust).the results of the analysis of the chemical composition of the melt water indicate an increased level of technogenic pollution of snow cover in all investigated functional areas of Voronezh.


2017 ◽  
Vol 8 (3) ◽  
pp. 113-120 ◽  
Author(s):  
Svetlana Sazonova ◽  
◽  
Sergei Rumiantsev
Keyword(s):  

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