Ambient temperature effects on DC behaviour of GaAs MESFET devices

1993 ◽  
Vol 140 (4) ◽  
pp. 305 ◽  
Author(s):  
J. Rodriguez-Tellez ◽  
B. Stothard
Keyword(s):  
Ambient Temperature ◽  
Temperature Effects ◽  
Gaas Mesfet

Ambient temperature effects on physiological traits of white-tailed deer

1975 ◽  
Vol 53 (6) ◽  
pp. 679-685 ◽  
Author(s):  
J. B. Holter ◽  
W. E. Urban Jr. ◽  
H. H. Hayes ◽  
H. Silver ◽  
H. R. Skutt
Keyword(s):  
Heart Rate ◽  
Body Temperature ◽  
Energy Expenditure ◽  
Ambient Temperature ◽  
Temperature Effects ◽  
Temperature Changes ◽  
Wind Chill ◽  
Ambient Temperatures ◽  
Energy Equilibrium ◽  
Body Energy

Six adult white-tailed deer (Odocoileus virginianus borealis) were exposed to 165 periods of 12 consecutive hours of controlled constant ambient temperature in an indirect respiration calorimeter. Temperatures among periods varied from 38 to 0 (summer) or to −20C (fall, winter, spring). Traits measured were energy expenditure (metabolic rate), proportion of time spent standing, heart rate, and body temperature, the latter two using telemetry. The deer used body posture extensively as a means of maintaining body energy equilibrium. Energy expenditure was increased at low ambient temperature to combat cold and to maintain relatively constant body temperature. Changes in heart rate paralleled changes in energy expenditure. In a limited number of comparisons, slight wind chill was combatted through behavioral means with no effect on energy expenditure. The reaction of deer to varying ambient temperatures was not the same in all seasons of the year.

Ambient temperature effects on hypothalamic, rectal and skin temperatures in Coturnix

Life Sciences ◽  
1966 ◽  
Vol 5 (20) ◽  
pp. 1887-1896 ◽  
Author(s):  
Mohamed K. Yousef ◽  
Larry Z. McFarland ◽  
Wilbor O. Wilson
Keyword(s):  
Ambient Temperature ◽  
Temperature Effects ◽  
Skin Temperatures

scholarly journals Ambient Temperature Effects on Driving

2015 ◽  
Vol 3 ◽  
pp. 3123-3127 ◽  
Author(s):  
Nazi Faisal A. Chowdhury
Keyword(s):  
Ambient Temperature ◽  
Temperature Effects

Ambient Temperature Effects Upon the Flow in Gas Pipelines at Low Speeds

2005 ◽  
Author(s):  
Gerald L. Morrison ◽  
Pardeep Brar
Keyword(s):  
Velocity Field ◽  
Flow Field ◽  
Ambient Temperature ◽  
Temperature Effects ◽  
Average Velocity ◽  
Gas Pipeline ◽  
Gas Pipelines ◽  
Flow Meter ◽  
Low Speeds ◽  
C 50

The flow field inside gas pipeline meter run is numerically simulated to determine the affects of upstream piping and temperature differences between the meter run pipe and the gas upon the flow. At bulk averaged velocities below 0.6 m/s (2 ft/s) significant changes in the velocity field are present which may alter the response of any flow meter mounted in the meter run. Examples for a bulk average velocity of 0.15 m/s (1/2 ft/s) and temperature differences with magnitudes of 27.7°C (50°F) are presented.

scholarly journals Temperature Effects on Vibration-Based Damage Detection of a Reinforced Concrete Slab

2020 ◽  
Vol 10 (8) ◽  
pp. 2869 ◽  
Author(s):  
Zhenpeng Wang ◽  
Minshui Huang ◽  
Jianfeng Gu
Keyword(s):  
Elastic Modulus ◽  
Reinforced Concrete ◽  
Ambient Temperature ◽  
Temperature Effects ◽  
Structural Damage ◽  
Natural Frequencies ◽  
Damage Identification ◽  
Mode Shapes ◽  
Arx Model ◽  
Rc Slab

To study the variations in modal properties of a reinforced concrete (RC) slab (such as natural frequencies, mode shapes and damping ratios) under the influence of ambient temperature, a laboratory RC slab is monitored for over a year, the simple linear regression (LR) and autoregressive with exogenous input (ARX) models between temperature and frequencies are established and validated, and a damage identification based on particle swarm optimization (PSO) is utilized to detect the assumed damage considering temperature effects. Firstly, the vibration testing is performed for one year and the variations of natural frequencies, mode shapes and damping ratios under different ambient temperatures are analyzed. The obtained results show that the change of ambient temperature causes a major change of natural frequencies, which, on the contrary, has little effect on damping ratios and modal shapes. Secondly, based on a theoretical derivation analysis of natural frequency, the models are determined from experimental data on the healthy structure, and the functional relationship between temperature and elastic modulus is obtained. Based on the monitoring data, the LR model and ARX model between structural elastic modulus and ambient temperature are acquired, which can be used as the baseline of future damage identification. Finally, the established ARX model is validated based on a PSO algorithm and new data from the assumed 5% uniform damage and 10% uniform damage are compared with the models. If the eigenfrequency exceeds the certain confidence interval of the ARX model, there is probably another cause that drives the eigenfrequency variations, such as structural damage. Based on the constructed ARX model, the assumed damage is identified accurately.

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