scholarly journals Plankton and turbidity : an investigation of time and space distribution of microorganisms and other materials producing attenuation of light in the open sea / E.G. Barham, J.W. Wilton, and M.P. Sullivan.

1966 ◽  
Author(s):  
E. G. Barham ◽  
M. P. Sullivan ◽  
J. W. Wilton
2013 ◽  
Vol 807-809 ◽  
pp. 628-631
Author(s):  
Xiao Yong Peng ◽  
Xin Zhang ◽  
Shuai Huang ◽  
Xu Sheng Chai ◽  
Lan Xia Guo

with a flat ground uranium tailings impoundment as the object of the paper, CFD technology was used to study the atmospheric dynamic diffusion characteristics and the evolution of time and space distribution of radon in the uranium tailings impoundment. Results show that, within 1500m range of the leeward of uranium tailings impoundment the falling gradient of radon mass fraction improves with distance increases at the same moment, however the falling gradient flattens with the increase of time gradually; During the first 30 minutes, the radon mass fraction of tailings impoundment in the leeward direction has a larger growth gradient, then flattens out slowly, and stabilizes after 75 minutes.


1992 ◽  
Vol 37 (4) ◽  
pp. 112-115 ◽  
Author(s):  
W.C.S. Smith ◽  
W.J. Mutch

Parkinson's disease is a common and disabling condition which principally affects the elderly. The time and space distribution of Parkinson's disease has been examined to determine if it provides clues as to aetiology and factors affecting its distribution. Previous studies have used mortality data,1 data from epidemiological studies,2 and pre scribing information particularly with regard to the use of levodopa.3 These studies have looked within countries and between countries.


2004 ◽  
Vol 19 (1-2) ◽  
pp. 19
Author(s):  
E. G. Cabral-Solís ◽  
E. Espino-Barr

Se analiza la abundancia en tiempo y espacio de los peces recolectados durante 18 muestreos mensuales en 21 estaciones distribuidas en la Laguna de Cuyutlán, México, durante el período de marzo a junio de 1999 y de octubre de 1999 a diciembre de 2000. Se recolectaron 1,719 organismos ícticos que pertenecen a 22 familias. Las especies más abundantes fueron: la mojarra rayada (Gerres cinereus) con 43.86 %, lebrancha (Mugil curema) con 24.89 %, mala capa (Diapterus peruvianus) con 6.34 %, sardina crinuda (Opisthonema libertate) con 5.29 % y con 3 % el jurel (Caranx caninus) y la piña (Oligo plitesaltus).La riqueza específica varió de 3.52 en mayo de 1999 a 15.48 en octubre de 2000. La equitatividad fluctuó de 0 en la estación 18, ubicada en el vaso de Palo Verde, a 0.93 en la estación 20 ubicada en el mismo vaso. El índice de diversidad presentó valores de 0.33 en mayo 1999 a 1.06 en octubre 2000. La laguna puede dividir se en dos vasos por sus características físicas y biológicas. La apertura de la Boca de Tepalcates aumentó la diversidad de especies de peces, pero habrá que dejar pasar el tiempo para conocer los cambios en biomasa. Time and space distribution and abundance of the fishes in the Cuyutlan Lagoon, Colima, Mexico Monthly sampling in 21 sites in the Cuyutlán Lagoon, México were carried out from March to June 1999 and October 1999 to December 2000, where 1,719 fish from 22 families were collected. The most abundant were: yellowfin mojarra (Gerres cinereus ) with 43.86 %, white mullet (Mugil curema ) in 24.89%, mojarra (Diapterus peruvianus ) with 6.34 %, Pacific thread herring (Opisthonema libertate ) with 5.29 % and with 3 % Pacific crevalle jack (Caranx caninus ) and long jaw leather jack (Oligoplites altus ). The specific richness changed from 3.52 in May 1999 to 15.48 in October 2000. The equitativity fluctuated from 0 in the 18th station named Palo Verde to 0.93 in the 20th site in the same area. The diversity index presented values from 0.33 in May 1999 to 1.06 in October 2000. By its physical and bio logical characteristics the lagoon can be divided in to two different areas. The opening of the channel Boca de Tepalcates increased the diversity of species of fish, but it will take time to know how the bio mass is going to change.


2016 ◽  
Vol 31 ◽  
pp. 91-99 ◽  
Author(s):  
Juan Sebastian Ulloa ◽  
Amandine Gasc ◽  
Phillipe Gaucher ◽  
Thierry Aubin ◽  
Maxime Réjou-Méchain ◽  
...  

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Qi Sun ◽  
Fang Sun ◽  
Cai Liang ◽  
Chao Yu ◽  
Yamin Zhang

Purpose Beijing rail transit can actively control the density of rail transit passenger flow, ensure travel facilities and provide a safe and comfortable riding atmosphere for rail transit passengers during the epidemic. The purpose of this paper is to efficiently monitor the flow of rail passengers, the first method is to regulate the flow of passengers by means of a coordinated connection between the stations of the railway line; the second method is to objectively distribute the inbound traffic quotas between stations to achieve the aim of accurate and reasonable control according to the actual number of people entering the station. Design/methodology/approach This paper analyzes the rules of rail transit passenger flow and updates the passenger flow prediction model in time according to the characteristics of passenger flow during the epidemic to solve the above-mentioned problems. Big data system analysis restores and refines the time and space distribution of the finely expected passenger flow and the train service plan of each route. Get information on the passenger travel chain from arriving, boarding, transferring, getting off and leaving, as well as the full load rate of each train. Findings A series of digital flow control models, based on the time and space composition of passengers on trains with congested sections, has been designed and developed to scientifically calculate the number of passengers entering the station and provide an operational basis for operating companies to accurately control flow. Originality/value This study can analyze the section where the highest full load occurs, the composition of passengers in this section and when and where passengers board the train, based on the measured train full load rate data. Then, this paper combines the full load rate control index to perform reverse deduction to calculate the inbound volume time-sharing indicators of each station and redistribute the time-sharing indicators for each station according to the actual situation of the inbound volume of each line during the epidemic. Finally, form the specified full load rate index digital time-sharing passenger flow control scheme.


Sign in / Sign up

Export Citation Format

Share Document