Long-Wave Component in Near-Bottom Velocities Under Random Waves on a Gentle Slope

1989 ◽  
Vol 32 (2) ◽  
pp. 149-159 ◽  
Author(s):  
Shinji Sato ◽  
Taro Isayama ◽  
Tomoya Shibayama
Keyword(s):  
Wave Component ◽  
Random Waves ◽  
Gentle Slope ◽  
Long Wave ◽  
Bottom Velocities

scholarly journals LONG PERIOD DISTURBANCES DUE TO WAVE GROUPS

1980 ◽  
Vol 1 (17) ◽  
pp. 37 ◽  
Author(s):  
E.C. Bowers
Keyword(s):  
Beat Frequency ◽  
Secondary Wave ◽  
Wave System ◽  
Regular Wave ◽  
Random Waves ◽  
Wave Groups ◽  
Long Period ◽  
Long Wave ◽  
Theoretical Predictions ◽  
Wave Maker

Measurements of long period disturbances associated with wave groups are compared with theoretical predictions. The experiments were carried out in a wave flume with an absorbing beach at one end. Tests were carried out using both regular wave groups (made up of two wave frequencies so that groups occur at a single beat frequency) and a random sea. The theoretical predictions are based on a Stokes expansion of the basic wave equations up to second order. The results are consistent with having three components in the long period disturbance at wave group periods. The first is set-down beneath wave groups, a disturbance that is tied to the wave groups travelling towards the beach. The second is a surf beat, a free long wave propagating back from the beach that is generated by reflection of the set-down from the beach. The third component is a secondary wave, a free long wave propagating towards the beach, that is generated by the wave-maker when it is only programmed to produce the primary wave system without its associated set-down beneath wave groups. The experimental results show that this third component can be minimised for both regular wave groups and a random sea by adding an appropriate long period movement of the wave-maker. Also, results are presented that indicate that long cycles of truly random waves, lasting many hours in model terms, are required to obtain reliable estimates of the effect of wave grouping on marine structures.

Measurements of Near-Bottom Velocities in Random Waves on a Constant Slope

1988 ◽  
Vol 31 (2) ◽  
pp. 219-229 ◽  
Author(s):  
Shinji Sato ◽  
Masaya Fukuhama ◽  
Kiyoshi Horikawa
Keyword(s):  
Random Waves ◽  
Constant Slope ◽  
Bottom Velocities

scholarly journals Photoluminescent Control Ripeness of the Seeds of Plants

2021 ◽  
Vol 273 ◽  
pp. 01003
Author(s):  
Mikhail Belyakov ◽  
Elena Sokolova ◽  
Valentina Listratenkova ◽  
Nina Ruzanova ◽  
Leonid Kashko
Keyword(s):  
A Priori ◽  
Spectral Characteristics ◽  
Short Wave ◽  
Luminescence Spectra ◽  
Wave Component ◽  
Linear Regression Models ◽  
Excitation Spectra ◽  
Long Wave ◽  
Urgent Task ◽  
Luminescent Radiation

The development of technology for objectively determining the ripeness of plant seeds is an urgent task of modern agricultural production. An alternative to existing methods is optical photoluminescent technology, which is characterized by high accuracy, selectivity, expressiveness, as well as being remote and non-destructive. The spectral characteristics of excitation and photoluminescence of wheat, oat, and corn seeds during their maturation were measured using a spectrofluorometer using a previously developed technique. It was found that during maturation, the short-wave component of the excitation spectra decreases (λs=362 nm) and the long-wave component increases (λl=485 nm). After measuring the luminescence spectra, the integral photoluminescence fluxes for long-wave and short-wave excitation, as well as their ratio, were determined. We have obtained statistically reliable linear regression models of the dependence of long-wave and short-wave photoluminescence flows on the maturation time. Based on the obtained dependencies, a technology was developed for determining the degree of physiological maturation and making decisions about harvesting ripe seeds. It includes sample preparation, excitation and registration of luminescent radiation, amplification of the received signals and their relations, obtaining information about the degree of ripeness taking into account a priori dependencies.

World Economic Crisis as a Process of Substitution of Technological Modes

2009 ◽  
pp. 26-38 ◽  
Author(s):  
S. Glaziev
Keyword(s):  
Economic Crisis ◽  
Economic Activity ◽  
Sharp Increase ◽  
Energy Resources ◽  
Long Wave ◽  
The World ◽  
World Economic ◽  
Technological Mode ◽  
World Economic Crisis

The article analyzes fundamental reasons for the world economic crisis in the light of global technological shifts. It proves that it is caused by the substitution of technological modes. It is shown that sharp increase and slump in stock indices and prices for energy resources are typical of the process of technological substitution which occurs regularly according to the rhythm of long-wave fluctuations of the world economic activity. The article rationalizes a package of anti-crisis measures aimed at stimulating the new technological mode. Its structure and role of the locomotive factor of the new long wave of economic growth are revealed.

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