Wyniki 1-2 spośród 2 dla zapytania: authorDesc:"Karlygash NURSEITOVA"

Improving the way of determination substances thermal physical characteristics by direct heating thermistor method DOI:10.15199/48.2019.04.21

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When determining the coefficient of thermal conductivity by direct heating thermistor method there is an error of calculation, the value of which depends on the method by determining the coefficient of thermal conductivity. This problem can be solved by optimal and accurate determination of the calibration coefficients used in the calculations. In this work has been carried out the research of errors occurring in the application of known methods and proposed a new method for determining the thermal conductivity of substances to improve the accuracy of their measurement. Formulation of the problem The purpose of this work is to research the error of measurement for existing methods for the determination of thermophysical characteristics (TPC) measured by the direct heating thermistor method to increase the measurement accuracy by choosing the optimal method of mathematical calculations for the thermal conductivity of substances under study by measuring the temperature of the thermistor's heating during it`s heating under the action of electric current. Main research material The essence of the direct heating thermistor method is to use the phenomenon of it`s self-heating due to flow through it of electric current. The temperature of the selfheating thermistor will depend on the environment in which it is located, that is, from the TPC of the research substance, which the thermistor has a thermal contact with. For an ideal model of a thermistor sensor in the ball form with radius r with ideal thermal conductivity, provided that the thermistor is surrounded by the research material, the coefficient of thermal conductivity is determined by the formula [1]: (1) r T Pt     4 where λ - thermal conductivity coefficient of the investigated material, W/(m·K); Pt - thermistor power, W; r - radius of the head of the thermistor, m; ΔT - temperature of the thermistor, оi[...]

Ultrasonic microcontroller device for distance measuring between dustcart and container of municipal solid wastes DOI:10.15199/48.2019.04.26

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Relevance of study of municipal solid wastes (MSW) management lies in the fact that it is included into one of the clauses of the Association Agreement between Ukraine and the European Union [1]. The MSW annual amount in Ukrainian localities constitutes more than 46 million m3 [2]. Among the technologies for MSW management in Ukraine, the most widespread is burial in landfills and garbage dumps (96.5%), incineration at incineration plants (2.2%) and recycling (1.3%). Collection and transportation of MSW to landfills and waste incinerators is carried out by bodyequipped dustcarts in the quantity exceeding 4100 vehicles [2], which have the following methods of loading solid waste into the body: rear (70%), lateral (25%) and front (5%) [3]. To position accurately the dustcart within the range of gripping MSW container with manipulator, driver-operator should know the exact distance between the dustcart and container. Therefore, in our opinion, it is expedient to install in the dustcart a device for measuring the distance with possibility of displaying the distance in the driver-operator’s cabin. This is especially important for rear and lateral MSW loading, being most common in use. According to Decision of the Cabinet of Ministers of Ukraine No. 265 [4], ensuring use of modern highly efficient dustcarts in the country's communal services as the main element in the structure of vehicles for collecting and initial treatment of municipal solid wastes, is a relevant scientific and technical problem. Development of instruments for measuring distance between the dustcart and municipal solid wastes container with consideration of environmental parameters is one of the important objectives for solution of this problem. The purpose of the study is development of a device for measuring distance between the dustcart and municipal solid wastes container as based on the study of existing signal processing methods and measuring of p[...]

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