scholarly journals Physical factors affecting the reliability of rail crane operators

Dependability ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 36-39
Author(s):  
T. A. Finochenko ◽  
I. G. Pereverzev ◽  
M. V. Balanova
Keyword(s):  
Experimental Studies ◽  
Clinical Signs ◽  
Physical Nature ◽  
High Energy ◽  
Point Of View ◽  
Physical Factors ◽  
Noise And Vibration ◽  
Factors Affecting ◽  
Industrial Noise ◽  
Experimental Findings

As it is known, load-lifting rail cranes of various models employed as part of Russian Railways repair and recovery trains are high-risk facilities. They normally have large dimensions and powerful engines that generate significant thrust and high energy. The paper examines the effects of harmful occupational factors of physical nature, i.e. industrial noise and vibration on the performance and health of rail crane operators. Aim. Based on the analysis of the causes of incidents that occurred in the course of operation of rail cranes, generalizing the experimental findings regarding the effects of industrial noise and vibration on crane operators and identifying the correlation between the clinical signs of distress in this category of workers and the levels of the above harmful physical industrial factors. Methods. Experimental studies and the subsequent evaluation of the effect of industrial noise and vibration generated by the mechanisms of cranes were conducted with the use of an Assistant Total+ noise and vibration analyzer in the course of operation of rail cranes of various models when handling cargo, as well as when crane engines idle. Measurements were conducted at workstations where the operator is to be at during the operation and maintenance of the crane, i.e. the control cabins, operator seat, control handles, near the crane engine. Results. The paper provides a classification of sources of noise and vibration that affect crane operators, experimental findings regarding the levels of industrial noise, general and local industrial vibration for various models of cranes. Clinical signs of distress are identified, a list is set forth of the most typical occupational health problems for this category of workers. Conclusions. The paper concludes that the reduction of industrial noise and vibration caused by the mechanisms of rail cranes is a relevant engineering and socioeconomic problem. From the socioeconomic point of view the solution to this problem will allow improving the working conditions of crane operators, while in terms of engineering it will enable higher technical and operational characteristics of crane mechanisms.

scholarly journals Methods for Improvement of the Thermal Efficiency during Spray Drying

2018 ◽  
Vol 53 ◽  
pp. 01031 ◽  
Author(s):  
Fangyuan Cheng ◽  
Xueyong Zhou ◽  
Yanmei Liu
Keyword(s):  
Spray Drying ◽  
Thermal Efficiency ◽  
High Energy ◽  
Point Of View ◽  
Low Energy ◽  
Energy Utilization ◽  
Spray Dryer ◽  
Unit Operation ◽  
Factors Affecting ◽  
High Energy Consumption

Spray drying is a kind of unit operation with high energy consumption and relatively low energy utilization, and the problem of low thermal efficiency has been attracted the attention by scholars at home and abroad. The factors affecting the thermal efficiency of spray dryer are analyzed. From a technical point of view, the thermal efficiency of spray dryer can be increased through the unit operation. Measurements for the reduction of energy saving of spray dryer were put forward.

scholarly journals Experimental studies of physical factors affecting seston transport in streams1

1987 ◽  
Vol 32 (4) ◽  
pp. 848-863 ◽  
Author(s):  
J. R. Webster ◽  
E. F. Benfield ◽  
S. W. Golladay ◽  
B. H. Hill ◽  
L. E. Hornick ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Physical Factors ◽  
Factors Affecting

scholarly journals Top-down resolution of visual ambiguity – knowledge from the future or footprints from the past?

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258667
Author(s):  
Jürgen Kornmeier ◽  
Kriti Bhatia ◽  
Ellen Joos
Keyword(s):  
A Priori ◽  
Necker Cube ◽  
Experimental Studies ◽  
Sensory Information ◽  
Stimulus Presentation ◽  
Point Of View ◽  
History Effects ◽  
The Future ◽  
Experimental Findings ◽  
And Behavior

Current theories about visual perception assume that our perceptual system weights the a priori incomplete, noisy and ambiguous sensory information with previous, memorized perceptual experiences in order to construct stable and reliable percepts. These theories are supported by numerous experimental findings. Theories about precognition have an opposite point of view. They assume that information from the future can have influence on perception, thoughts, and behavior. Several experimental studies provide evidence for precognition effects, other studies found no such effects. One problem may be that the vast majority of precognition paradigms did not systematically control for potential effects from the perceptual history. In the present study, we presented ambiguous Necker cube stimuli and disambiguated cube variants and systematically tested in two separate experiments whether perception of a currently observed ambiguous Necker cube stimulus can be influenced by a disambiguated cube variant, presented in the immediate perceptual past (perceptual history effects) and/or in the immediate perceptual future (precognition effects). We found perceptual history effects, which partly depended on the length of the perceptual history trace but were independent of the perceptual future. Results from some individual participants suggest on the first glance a precognition pattern, but results from our second experiment make a perceptual history explanation more probable. On the group level, no precognition effects were statistically indicated. The perceptual history effects found in the present study are in confirmation with related studies from the literature. The precognition analysis revealed some interesting individual patterns, which however did not allow for general conclusions. Overall, the present study demonstrates that any future experiment about sensory or extrasensory perception urgently needs to control for potential perceptual history effects and that temporal aspects of stimulus presentation are of high relevance.

New Studies of Vulcanization the T-50 Test

1954 ◽  
Vol 27 (3) ◽  
pp. 648-670
Author(s):  
Arturo Chiesa
Keyword(s):  
Activation Energy ◽  
Elevated Temperatures ◽  
Practical Importance ◽  
Physical Nature ◽  
Point Of View ◽  
Correlation Diagram ◽  
Physical Factors ◽  
Comprehensive Picture ◽  
Order Of Magnitude ◽  
Physical Phenomena

Abstract The T-50 test, which has already been used for the last twenty years in many rubber factories has, up to the present time, been used solely as a means of checking vulcanization conditions, and so far no one has attempted to derive any mathematical relations from the results obtained. In the first part of this work it is shown that the T-50 test can be regarded as a useful and efficient means for studying much more complex and important problems, as, for example, the determination of the vulcanization characteristics of a rubber compound, both with respect to the ingredients and from the thermal point of view. In fact, this test makes it possible to obtain quantative data rapidly, which can be utilized to render any study easier and more conclusive than is possible with other tests commonly used, e.g., dynamometric parameters, aging tests, relaxation at elevated temperatures, etc. In making a study of the T-50 test, the approach was from the point of view of the chemical and physical nature of the phenomena involved in the test. It has been established with a considerable degree of exactitude that results obtained with the test conform to an energy law common to many chemical-physical phenomena, viz., the law of Arrhenius, which expresses the relation between the rate of a reaction and the temperature of a process by means of a parameter which depends on the activation energy of the process itself. In fact, analysis of experimental data shows clearly that, except in the case of mixtures having peculiar vulcanization characteristics, the activation energy of the process is practically independent of the composition of the mixture. One is led to believe, therefore, that such energy depends directly on the nature of the polymer itself and on its vulcanization reactions with sulfur, and that it is independent of the chemical and physical factors which control vulcanization reactions. On account of the nature of our work, we could not undertake a thorough scientific study of the aspect of this fact, considered from the point of view of the molecular structure of cross-linked high polymers. Instead, we have limited ourselves to developing an application of considerable practical utility, based on the fact that the activation energy is practically constant. In fact, a simple correlation diagram can be established which can be used for most types of vulcanizates, and by means of which it is possible to obtain directly the equivalent coefficients for passing from one vulcanization temperature to another with the longest temperature range which it was possible to use, i.e., from 78° to 151 ° C. It has thus been possible to interpret the results of the T-50 test for temperatures other than for the temperature at which the test was made, and thus to obtain a more complete and comprehensive picture directly related to the same chemico-physical phenomena. Passing on to the subject of dynamometric parameters, it is shown that, for these too, the above law applies with sufficient approximation. Again, since the order of magnitude of the activation energy is similar to that found by the T-50 test, the same correlation diagram applies, thus appreciably increasing its practical importance. Finally, the satisfactory accord between the activation energy values obtained by the T-50 test and those obtained by stress relaxation tests reveals an intimate relation between the two phenomena, which otherwise would appear to be completely different. Thus a further contribution is made to the complex study of relaxation.

scholarly journals The Issues of Cryojet Technology Application for Rock Cutting

2018 ◽  
Vol 41 ◽  
pp. 03010
Author(s):  
Konstantin Golovin ◽  
Roman Kovalev ◽  
Andrey Kopylov
Keyword(s):  
High Speed ◽  
Cutting Tools ◽  
Experimental Studies ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Point Of View ◽  
Factors Affecting ◽  
Technology Application ◽  
High Cutting Speed ◽  
Main Factors

Water-jet technologies, based on the use of high-speed jets as cutting tools, are one of the promising directions of the destruction technologies for various materials. Jets’ capability to cut even very strong, anisotropic and composite materials, as well as their high cutting speed, that can be reached without workpiece reaction occurring on the tool, make them attractive from the point of view of their implementation as cutting tools. This paper outlines the methods of materials destruction by means of high-speed cryojet and discusses future areas of its application. The research reveals the main factors and criteria for evaluating the effectiveness of cryojet cutting. Experimental studies of the main factors affecting the cryojet cutting parameters were carried out using a bench unit. As a result of the experimental data analysis, we found the correspondences that can be used for calculating the cryojet cutting of various materials.

scholarly journals Radon Over Kimberlite Pipes: Estimation of the Emanation Properties of Rocks (Lomonosov Diamond Deposit, NW Russia)

2021 ◽  
Vol 11 (13) ◽  
pp. 6065
Author(s):  
Evgeny Yakovlev ◽  
Andrey Puchkov
Keyword(s):  
Experimental Studies ◽  
State Level ◽  
The Body ◽  
Free State ◽  
Physical Factors ◽  
Diamond Deposit ◽  
Factors Affecting ◽  
Emanation Coefficient ◽  
Host Rocks ◽  
The Impact

In this paper, using the example of the Lomonosov diamond deposit, experimental studies of rocks were carried out to assess the main radiation and physical factors affecting the formation of the radon field over the kimberlite pipes of the Arkhangelsk diamondiferous province. For various types of rocks, represented by vent kimberlites, tuffaceous-sedimentary rocks of the crater and enclosing and overlying sediments, the following were studied: porosity, density, activity of radium-226, activity of radon in a free state, level of radon production, and emanation coefficient. The research results showed that the greatest amount of radon in a free state is produced by rocks of the near-pipe space, represented by the enclosing Vendian V2 deposits and characterized by high values of the emanation coefficient, radium activity, radon production level and porosity. This fact is associated with the structural and geological features of the near-pipe space, which was exposed to the impact of kimberlite magma on the host rocks. The lowest values of these parameters are characteristic of the kimberlites of the vent facies, which limits the formation of free radon in the body of the pipe. The results of the experimental studies create prospects for the development of emanation methods for searching for kimberlite pipes in the conditions of the Arkhangelsk diamondiferous province.

scholarly journals The Factors Affecting the Students' Low Accumulative Averages at Palestine Technical university- Khadoorie from The Students' Point of View

2019 ◽  
Vol 3 (20) ◽  
Author(s):  
Jaafar Wasfi Abu Saa
Keyword(s):  
Point Of View ◽  
Physical Factors ◽  
Economic Factors ◽  
Personal Factors ◽  
Factors Affecting ◽  
Academic Level ◽  
Technical University ◽  
Educational Factors ◽  
The University ◽  
Socio Economic Factors

This study aimed to investigate the factors affecting the students' low accumulative averages at Palestine Technical university- Khadoorie from the students' point of view using the descriptive analytical approach. The research tool was a four-dimensional questionnaire reflecting the potential factors affecting the students' low accumulative averages, namely: personal factors, socio-economic, factors, educational factors, and environmental and physical factors. For the purpose of this study, these factors were tested on a random sample of (354) male and female students from different faculties at the university. The study showed the following results: - The overall average of the factors affecting the students' low accumulative averages at Palestine Technical university- Kadoorie from the student’s point of view was (3.08); that is, "medium" in words. Concerning the four dimensions, the overall average of the educational factors was (4.06), followed by socio-economic factors with an overall average of (4.05), then personal factors with an overall average of (4.03). All of the three aforementioned dimensions had a “high” rating, while the environmental and physical factors lastly had a “medium” rating with an overall average of (3.16). - With reference to the variables of gender, faculty and academic level, no statistical differenceswere found between the factors affecting the students' low accumulative averages at Palestine Technical university- Khadoorie from the student’s point of view. In light of the findings, a number of recommendations and suggestions to improve the students' low accumulative averages and reduce the factors leading to low accumulative averages have been made for the university. First of all, a course that introduces students to university life, its requirements, and the laws and regulations in force at the university should be offered. Secondly, workshop son questions preparation and formulation should be held for the university faculty members. Moreover, poor students should be helped in order to be fully committed to education.  

In situ TEM studies of irradiation effects for materials improvement

1991 ◽  
Vol 49 ◽  
pp. 452-453
Author(s):  
Charles W. Allen
Keyword(s):  
Nuclear Reactor ◽  
Austenitic Stainless Steels ◽  
High Energy ◽  
Point Of View ◽  
In Situ Tem ◽  
Irradiation Effects ◽  
Tem Analysis ◽  
Radiation Induced ◽  
Analytical Tools

Irradiation effects studies employing TEMs as analytical tools have been conducted for almost as many years as materials people have done TEM, motivated largely by materials needs for nuclear reactor development. Such studies have focussed on the behavior both of nuclear fuels and of materials for other reactor components which are subjected to radiation-induced degradation. Especially in the 1950s and 60s, post-irradiation TEM analysis may have been coupled to in situ (in reactor or in pile) experiments (e.g., irradiation-induced creep experiments of austenitic stainless steels). Although necessary from a technological point of view, such experiments are difficult to instrument (measure strain dynamically, e.g.) and control (temperature, e.g.) and require months or even years to perform in a nuclear reactor or in a spallation neutron source. Consequently, methods were sought for simulation of neutroninduced radiation damage of materials, the simulations employing other forms of radiation; in the case of metals and alloys, high energy electrons and high energy ions.

Masonry: the brittle or plastic material?

2019 ◽  
pp. 22-28
Keyword(s):  
Plastic Material ◽  
Experimental Studies ◽  
Point Of View ◽  
Plastic Properties ◽  
Plastic Deformations ◽  
Base Materials ◽  
Stress States ◽  
Creep Deformations ◽  
Structural Point

The results of experimental studies of masonry on the action of dynamic and static (short-term and long-term) loads are presented. The possibility of plastic deformations in the masonry is analyzed for different types of force effects. The falsity of the proposed approach to the estimation of the coefficient of plasticity of masonry, taking into account the ratio of elastic and total deformations of the masonry is noted. The study of the works of Soviet scientists revealed that the masonry under the action of seismic loads refers to brittle materials in the complete absence of plastic properties in it in the process of instantaneous application of forces. For the cases of uniaxial and plane stress states of the masonry, data on the coefficient of plasticity obtained from the experiment are presented. On the basis of experimental studies the influence of the strength of the so-called base materials (brick, mortar) on the bearing capacity of the masonry, regardless of the nature of the application of forces and the type of its stress state, is noted. The analysis of works of prof. S. V. Polyakov makes it possible to draw a conclusion that at the long application of the load, characteristic for the masonry are not plastic deformations, but creep deformations. It is shown that the proposals of some authors on the need to reduce the level of adhesion of the mortar to the brick for the masonry erected in earthquake-prone regions in order to improve its plastic properties are erroneous both from the structural point of view and from the point of view of ensuring the seismic resistance of structures. It is noted that the proposal to assess the plasticity of the masonry of ceramic brick walls and large-format ceramic stone with a voidness of more than 20% is incorrect, and does not meet the work of the masonry of hollow material. On the basis of the analysis of a large number of research works it is concluded about the fragile work of masonry.

DIESEL ENGINE OPERATION IN USE OF FUEL WITH ADDITIVES

2018 ◽  
pp. 18-24
Author(s):  
Petar Kazakov ◽  
Atanas Iliev ◽  
Emil Marinov
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Diesel Fuel ◽  
Internal Combustion Engines ◽  
Experimental Studies ◽  
Combustion Engines ◽  
Engine Operation ◽  
Factors Affecting ◽  
Operating Modes ◽  
Positive Effects

Over the decades, more attention has been paid to emissions from the means of transport and the use of different fuels and combustion fuels for the operation of internal combustion engines than on fuel consumption. This, in turn, enables research into products that are said to reduce fuel consumption. The report summarizes four studies of fuel-related innovation products. The studies covered by this report are conducted with diesel fuel and usually contain diesel fuel and three additives for it. Manufacturers of additives are based on already existing studies showing a 10-30% reduction in fuel consumption. Comparative experimental studies related to the use of commercially available diesel fuel with and without the use of additives have been performed in laboratory conditions. The studies were carried out on a stationary diesel engine СМД-17КН equipped with brake КИ1368В. Repeated results were recorded, but they did not confirm the significant positive effect of additives on specific fuel consumption. In some cases, the factors affecting errors in this type of research on the effectiveness of fuel additives for commercial purposes are considered. The reasons for the positive effects of such use of additives in certain engine operating modes are also clarified.

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