MATHEMATICAL MODELING OF EAR GRAIN SEPARATION PROCESS DEPENDING ON THE LENGTH OF THE AXIAL FLOW THRESHING APPARATUS

Modeling the threshing and separation process involves the application of a method of description, analysis and analytical determination of system performance: threshing apparatus - working process. The modeling of the process of separating the seeds passing through an axial flow threshing device was performed taking into account that the separation function ss(x) is given depending on the length of the threshing apparatus. Then, models were made to describe the variation of the percentage (cumulative) of separated seeds ss (x=L), corresponding to the modification of the threshing apparatus functional parameters (depending on the peripheral speed of the rotor, the flow of straw parts and the moisture of straw parts).

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Determination of the speed of air outflow from the ventilation shaft of the warm attic of a multi-storey residential building under different initial conditions

Вестник гражданских инженеров ◽

10.23968/1999-5571-2021-18-5-126-129 ◽

2021 ◽

Vol 18 (5) ◽

pp. 126-129

Author(s):

E. A. Anshukova ◽

Keyword(s):

Mathematical Modeling ◽

System Performance ◽

Natural Ventilation ◽

Initial Conditions ◽

Ventilation System ◽

Residential Building ◽

Operating Conditions ◽

Ventilation Shaft

The operating conditions of a warm attic as an element of natural ventilation of a multi-storey residential building have an impact on the efficiency of the entire ventilation system performance, as well as on the condition of the enclosing structures. The study of the distribution of microclimate parameters in its volume makes it possible to more fully assess the ongoing processes. The result of calculating the rate of air outflow from the ventilation shaft of a warm attic by mathematical modeling is provided.

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Mathematical modeling of the corpse cooling under conditions of varying ambient temperature

Russian Journal of Forensic Medicine ◽

10.17816/fm360 ◽

2021 ◽

Vol 7 (1) ◽

pp. 29-35

Author(s):

German V. Nedugov

Keyword(s):

Mathematical Modeling ◽

Mathematical Model ◽

Ambient Temperature ◽

Analytical Determination ◽

Time Of Death ◽

Main Condition ◽

Proposed Model ◽

Thermometric Determination ◽

Early Postmortem

Background: The constancy of the ambient temperature is the main condition to correctly determine the time of death by thermometric method. However, in practice, this requirement is met only in cases of death in closed rooms. In this study, an exponential mathematical model was proposed for corpse cooling under any changes in ambient temperature. Aim: This study aimed to develop a mathematical model to determine the time of death based on the NewtonRichman cooling law in changing ambient temperature conditions. Materials and methods: Mathematical modeling of corpse cooling under changing ambient temperature is performed, focusing on problem solving of thermometric determination of the time of death. The axillary hollow was used as the diagnostic zone of the corpse, and the temperature of which at the time of death is taken is 36.6С. Results: A method of reverse reproduction of the cadaver temperature in conditions of changing ambient temperature has been developed. Results allow a relatively simple analytical determination of the time of death in the early postmortem period. Conclusions: The proposed method is advisable to be used in forensic medical practice to determine the time of death in early postmortem period. The developed mathematical model is implemented in the format of the application program Warm Bodies NRN. Use of tympanic and intraocular thermometry was recommended within the proposed model.

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