scholarly journals Center of gravity and ""effective wave length"" of transmission pyrometer color screens, and the extrapolation of the high temperature scale

1916 ◽  
Vol 12 (4) ◽  
pp. 483 ◽  
Author(s):  
P. D. Foote
Keyword(s):  
High Temperature ◽  
Temperature Scale ◽  
Wave Length ◽  
Center Of Gravity ◽  
Color Screens ◽  
Effective Wave

scholarly journals Interferential comparison of the red and other radiations emitted by a new cadmium lamp and the michelson lamp

1933 ◽  
Vol 139 (837) ◽  
pp. 202-218 ◽  
Keyword(s):  
Fine Structure ◽  
High Temperature ◽  
Wave Length ◽  
The Other ◽  
Reference Standard ◽  
Definite Evidence ◽  
Electro Magnetic ◽  
The Many ◽  
Red Radiation ◽  
Red Line

It is now generally recognised that future definitions of the units of length will probably be based on the length of a wave of visible light. At present the wave-length of the red radiation of cadmium serves as the basis of all measurements of the lengths of electro-magnetic waves which are perceptible by optical means, and provisional sanction has been given to measurements of length on the same basis, as an alternative to direct reference to the metre. Whether the cadmium red radiation provides the best reference standard for all measurements of length has not yet been definitely established. Two international committees, one representing spectroscopists and the other metrologists, have sanctioned standard specifications for cadmium lamps of the Michelson type from which the red radiation may be produced. The two specifications differ from one another in certain details, but both are subject to the same objections. These objections are directed partly against the high temperature at which it is necessary to run the lamp and partly against the high voltage required to excite the radiation. Therefore, such hyperfine structure and asymmetry as may be present in the red line of cadmium is likely to be masked in the Michelson lamp by a combination of two phenomena —the enhanced Doppler effect due to the high temperature of the radiating cadmium atoms, and the effect of the moderately high intensity of the electric field. Were this not so, it might be somewhat surprising that no definite evidence of fine structure or asymmetry had so far been observed in the red line from the Michelson lamp, notwithstanding the many careful examinations, with the aid of the most sensitive interferometers, to which this line has been subjected, in view of its importance as the reference standard for all other wave-lengths. Recently Nagaoka and Sugiura have recorded that they have observed slight evidences of structure in the red radiation when excited under special conditions in which great precautions were taken to ensure extreme sharpness of the line. It is believed, however, that no subsequent confirmation of this effect has yet been published.

Realization of High-Temperature Reference Point of the Temperature Scale for the Phase Transition of a δMoC–C Metal-Carbon Compound

2019 ◽  
Vol 61 (12) ◽  
pp. 1159-1165
Author(s):  
B. B. Khlevnoy ◽  
I. A. Grigor’eva ◽  
E. A. Ivashin ◽  
S. A. Ogarev ◽  
V. I. Sapritsky
Keyword(s):  
Phase Transition ◽  
High Temperature ◽  
Reference Point ◽  
Temperature Scale ◽  
Carbon Compound ◽  
Temperature Reference

scholarly journals On the Establishment of the High Temperature Scale

1907 ◽  
Vol 24 (5) ◽  
pp. 441-444
Author(s):  
C. W. Waidner ◽  
G. K. Burgess
Keyword(s):  
High Temperature ◽  
Temperature Scale

scholarly journals Estimation of Effective Wave Slope Coefficient of Ships with Large Breadth and Draught Ratio

Kapal ◽  
2020 ◽  
Vol 17 (1) ◽  
pp. 40-49
Author(s):  
Daeng Paroka ◽  
Andi Haris Muhammad ◽  
Sabaruddin Rahman
Keyword(s):  
Model Experiment ◽  
Center Of Gravity ◽  
Slope Coefficient ◽  
Beam Seas ◽  
Alternative Method ◽  
Strip Theory ◽  
Wave Slope ◽  
Effective Wave ◽  
Weather Criterion ◽  
Theory And Model

One of parameters to estimate heel angle of a ship in beam seas is effective wave slope coefficient. In the weather criterion of IMO, the effective wave slope coefficient is determined as function of ratio between distance of center of gravity from the sea surface and the ship draught. The others methods could be used to estimate the effective wave slope coefficient are simplified strip theory and model experiment. A ship with shallow draught and large vertical center of gravity can have an effective wave slope coefficient larger than 1.0 if the coefficient is calculated by using the formulae of weather criterion. Therefore, an alternative method to estimate the coefficient is necessary when it is applied to ships with geometry characteristics different with those used to develop the formulae. This research conducts to estimate the effective wave slope coefficient using three different methods, namely the formulae of weather criterion, the simplified strip theory and model experiment. Results of the three methods may provide enough evidence about suitable method to estimate the effective wave slope coefficient of ships with breadth and draught ratio larger than 3.5 like the Indonesian ro-ro ferries. Results and discussion show that the effective wave slope coefficient obtained by using the formulae of weather criterion is larger compared to that obtained by using the simplified strip theory and the model experiment. Here, the result of simplified strip theory for wave frequency the same as the roll natural frequency of subject ship is similar with the result of model experiment. This results show that the simplified strip theory can be used as an alternative method to determine the effective wave slope of a ship with breadth and draught ratio larger than 3.5 if the result of model experiment does not available.

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