scholarly journals Determination of Material Thicknesses in Protective Clothing for Firefighters

2018 ◽  
Vol 26 (2(128)) ◽  
pp. 93-99 ◽  
Author(s):  
Ryszard Korycki
Keyword(s):  
Heat Flux ◽  
Differential Equations ◽  
Exposure Time ◽  
Protective Clothing ◽  
Initial Conditions ◽  
Short Exposure ◽  
Short Exposure Time ◽  
Numerical Example ◽  
Second Order Differential Equations

The basic protective clothing for firefighters does not contact the flame and provides a relatively short exposure time to heat flux of prescribed density. Simultaneously the structure is subjected to sweat diffusion from the skin. The problem is determined mathematically by means of second-order differential equations accompanied by a set of boundary and initial conditions. Determination of the material thicknesses is gradient oriented. The optimal thicknesses are determined as a numerical example.

Speed Analysis of Laser Speckle Contrast with Ultra-Short Exposure Time

2018 ◽  
Vol 38 (4) ◽  
pp. 0411008
Author(s):  
安晓英 An Xiaoying ◽  
张茹 Zhang Ru ◽  
宋丽培 Song Lipei ◽  
武鹏飞 Wu Pengfei
Keyword(s):  
Exposure Time ◽  
Laser Speckle ◽  
Short Exposure ◽  
Short Exposure Time ◽  
Speckle Contrast

Short Exposure Time Characteristics Of X-Ray Generators

1983 ◽  
Author(s):  
Bruce A. Horn ◽  
Kim C. Luk ◽  
David M. Thomasson ◽  
Charles E. Finney
Keyword(s):  
Exposure Time ◽  
Short Exposure ◽  
Short Exposure Time ◽  
X Ray

Short Exposure Time Sensitivity of White Cells to Shear Stress

ASAIO Journal ◽  
2003 ◽  
Vol 49 (6) ◽  
pp. 687-691 ◽  
Author(s):  
Janell Carter ◽  
Katia Hristova ◽  
Hiroaki Harasaki ◽  
W. A. Smith
Keyword(s):  
Shear Stress ◽  
Exposure Time ◽  
Short Exposure ◽  
Short Exposure Time ◽  
Time Sensitivity

X-Ray Analysis of Stress in a Localized Area by Use of Imaging Plate

1991 ◽  
Vol 35 (A) ◽  
pp. 537-543 ◽  
Author(s):  
Yasuo Yoshioka ◽  
Shin'ichi Ohya
Keyword(s):  
Short Exposure ◽  
Imaging Plate ◽  
Image Analyzer ◽  
Single Exposure ◽  
Short Exposure Time ◽  
X Ray ◽  
Area Detector ◽  
Lattice Strains ◽  
Exposure Method

AbstractFor determination of stress in a localized area, we combined a modified single exposure technique and the imaging plate, which is an x-ray digital area detector. With the, single exposure method, stress value is obtained from lattice strains in two directions with a single incident x-ray beam directed at an oblique angle. However, since diffraction data around a whole Debye-Scherrer ring was used in this study, a stress value can be accurately determined in comparison with the single exposure method. We observed the DS ring by use of the imaging plate with requiring only a short exposure time. Lattice strains in many directions on a DS ring were measured by an image analyzer connected to a computer; we verified the effectiveness of this method.

Antigiardiasic activity of Cu(II) coordination compounds: Redox imbalance and membrane damage after a short exposure time

2019 ◽  
Vol 195 ◽  
pp. 83-90 ◽  
Author(s):  
Yadira Rufino-González ◽  
Martha Ponce-Macotela ◽  
Juan Carlos García-Ramos ◽  
Mario N. Martínez-Gordillo ◽  
Rodrigo Galindo-Murillo ◽  
...  
Keyword(s):  
Exposure Time ◽  
Coordination Compounds ◽  
Membrane Damage ◽  
Short Exposure ◽  
Short Exposure Time ◽  
Redox Imbalance

Application of Ambarzumian’s Method to Radiant Interchange in a Rectangular Cavity

1974 ◽  
Vol 96 (2) ◽  
pp. 191-196 ◽  
Author(s):  
A. L. Crosbie ◽  
T. R. Sawheny
Keyword(s):  
Differential Equation ◽  
Heat Flux ◽  
Integral Equation ◽  
Differential Equations ◽  
Ordinary Differential Equations ◽  
Nonlinear Integral Equation ◽  
Initial Conditions ◽  
Rectangular Cavity ◽  
Wide Range ◽  
First Time

Ambarzumian’s method had been used for the first time to solve a radiant interchange problem. A rectangular cavity is defined by two semi-infinite parallel gray surfaces which are subject to an exponentially varying heat flux, i.e., q = q0 exp(−mx). Instead of solving the integral equation for the radiosity for each value of m, solutions for all values of m are obtained simultaneously. Using Ambarzumian’s method, the integral equation for the radiosity is first transformed into an integro-differential equation and then into a system of ordinary differential equations. Initial conditions required to solve the differential equations are the H functions which represent the radiosity at the edge of the cavity for various values of m. This H function is shown to satisfy a nonlinear integral equation which is easily solved by iteration. Numerical results for the H function and radiosity distribution within the cavity are presented for a wide range of m values.

scholarly journals Comparison Between Single-Aperture and Multi-Aperture Approaches to Computer Correction of Images

2020 ◽  
Vol 237 ◽  
pp. 06003
Author(s):  
Vadim Dudorov ◽  
Anna Eremina
Keyword(s):  
Numerical Simulation ◽  
Exposure Time ◽  
Image Synthesis ◽  
Short Exposure ◽  
Small Scale ◽  
Short Exposure Time ◽  
Observation Systems ◽  
Order Of Magnitude ◽  
Single Aperture ◽  
Time Required

The effectiveness of the reconstruction of images formed by single- and multi-aperture systems and distorted by an atmospheric turbulence is analyzed in this work. Based on numerical simulation, we show that the use of multi-aperture observation systems for the computer correction of atmospheric distortions under anisoplanar conditions can significantly reduce the exposure time. Main distortions are well corrected during image synthesis for a short exposure time, which corresponds to a “frozen” turbulence. The time required for the correction of residual small-scale distortions is an order of magnitude shorter than in the case of synthesis of long-exposure images with the use of traditional single-aperture observation systems.

scholarly journals ESTIMATING THE INFLUENCE OF THE WIND EXPOSURE ON THE MOTION OF AN EXTINGUISHING SUBSTANCE

2020 ◽  
Vol 5 ◽  
pp. 51-59
Author(s):  
Yuriy Abramov ◽  
Oleksii Basmanov ◽  
Valentina Krivtsova ◽  
Andrii Khyzhnyak
Keyword(s):  
Differential Equations ◽  
Initial Conditions ◽  
Wind Effect ◽  
System Of Differential Equations ◽  
Wind Action ◽  
Fire Extinguishing ◽  
Additive Component ◽  
Wind Exposure ◽  
Using Data

One of the tasks to be solved when deploying fire extinguishing systems is to determine the range of the fire extinguishing agent supply to the combustion center. This problem is solved using data on the trajectory of the fire-extinguishing agent in the combustion center. The presence of wind impact on the process of supplying a fire extinguishing agent will lead to a change in its trajectory. To take into account wind impact, it becomes necessary to assess the result of such impact. Using the basic equation of dynamics for specific forces, a system of differential equations is obtained that describes the delivery of a fire extinguishing agent to the combustion center. The system of differential equations takes into account the presence of wind impact on the movement of the extinguishing agent. The presence of wind action is taken into account by the initial conditions. To solve such a system, the integral Laplace transform was used in combination with the method of undefined coefficients. The solution is presented in parametric form, the parameter of which is time. For a particular case, an expression is obtained that describes the trajectory of the supply of the extinguishing agent into the combustion center. Nomograms are constructed, with the help of which the operative determination of the estimate of the maximum range of the fire-extinguishing agent supply is provided. Estimates are obtained for the time of delivery of a fire-extinguishing agent to the combustion center, and it is shown that for the characteristic parameters of its delivery, this value does not exceed 0.5 s. The influence of wind action on the range of supply of a fire extinguishing agent is presented in the form of an additive component, which includes the value of the wind speed and the square of the time of its delivery. To assess the effect of wind impact on the movement of the fire extinguishing agent, an analytical expression for the relative error was obtained and it was shown that the most severe conditions for supplying the fire extinguishing agent to the combustion center, the value of this error does not exceed 5.5%. Taking into account the wind effect when assessing the range of supply of a fire-extinguishing agent makes it possible to increase the efficiency of fire-extinguishing systems due to its more accurate delivery to the combustion center

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