The Nitrogen Simulation Model, DRAINMOD-N II: Field Testing and Model Application for Contrasting Soil Types and Climatological Conditions

Author(s):  
M. A. Youssef ◽  
R. W. Skaggs
2007 ◽  
Vol 17 (1) ◽  
pp. 135-144 ◽  
Author(s):  
Milan Markovic ◽  
Milos Ivic ◽  
Norbert Pavlovic ◽  
Sladjana Jankovic

In this paper the idea of treating the operational service workers as the elements of technique systems is suggested and the renewal theory is used to forecast the number of accidents caused by human factor. The analytical model is presented and limitations for its application are quoted. Furthermore, the simulation model is developed and the conditions for its use are given. The model observes each worker separately and establishes the exact time of arisen failures, the number of failures at some moment t, time tn, to the nth failure, inconsistency of failure number and total number of failures of the observed population. The model is tested on the sample of 348 engine drivers in PE "Serbian Railways" who have made at leas one accident, in order to research the parameters necessary for using the renewal theory and simulation. .


2004 ◽  
Vol 130 (6) ◽  
pp. 511-519 ◽  
Author(s):  
F. Dechmi ◽  
E. Playán ◽  
J. Cavero ◽  
A. Martínez-Cob ◽  
J. M. Faci

1997 ◽  
Vol 40 (5) ◽  
pp. 1495-1500 ◽  
Author(s):  
R. H. Mohtar ◽  
J. D. Jabro ◽  
D. R. Buckmaster

2012 ◽  
Vol 45 (6) ◽  
pp. 1047-1052 ◽  
Author(s):  
S. Khebbache-Hadji ◽  
Y. Hani ◽  
N. Lahiani ◽  
A. El Mhamedi

2008 ◽  
Vol 48 (3) ◽  
pp. 313 ◽  
Author(s):  
A. S. Peake ◽  
M. J. Robertson ◽  
R. J. Bidstrup

Optimum plant population and irrigation strategies for maize grown in the Dalby district of the Darling Downs in Queensland, Australia, were investigated using the APSIM crop simulation model. After testing the model against three seasons of experimental data, simulation experiments using different irrigation strategies were conducted across a range of plant populations ranging from 20 000 to 80 000 plants/ha, on two soil types with plant available water capacities (PAWC) of 146 mm and 220 mm. All soil type × plant population × irrigation strategy scenarios were simulated using the historical climate record for Dalby from 1889 to 2004, in order to obtain long-term average yield and gross margins (LGM) for each scenario. Soil water was reset to two-thirds of PAWC at sowing in each year. Plant populations required to achieve maximum LGMs ranged from 50 000 to 80 000 plants/ha across the range of scenarios, and were higher than currently recommended by district agronomists for partially irrigated maize. The use of higher plant populations increased season-to-season variability in grain yield and gross margins and may not be a suitable strategy for growers who do not want to increase their risk of crop failure. Partially irrigated maize achieved substantially higher gross margins in years where a positive Southern Oscillation Index phase was recorded in August, and the use of higher plant populations in such years also increased long-term profitability, but also increased the risk of crop failure. Economic gains were achieved by varying the timing and amount of irrigation within a limited available irrigation volume, with a single 100 mm irrigation giving greater LGMs than two 50 mm irrigation events on both soil types, when the irrigation events were scheduled to fill a soil water deficit equal to the effective irrigation volume. However, under full irrigation the use of smaller irrigation volumes increased LGMs on the 146 mm PAWC soil, demonstrating the importance of timely irrigation scheduling on low PAWC soils.


Irriga ◽  
2003 ◽  
Vol 8 (1) ◽  
pp. 51-62
Author(s):  
Carlos Alberto Vieira de Azevedo ◽  
Roberto Vieira Pordeus ◽  
Jonildo Irenildo Silveira ◽  
Vera Lúcia Antunes de Lima ◽  
José Dantas Neto

INFLUÊNCIA DA LÂMINA REQUERIDA NO DESEMPENHO DA IRRIGAÇÃO POR SULCO  Carlos Alberto Vieira de Azevedo Roberto Vieira Pordeus Jonildo Irenildo SilveiraVera Lúcia Antunes de Lima José Dantas NetoDepartamento de Engenharia Agrícola, Universidade Federal de Campina Grande, Campina Grande, PB. CEP 58109-970. E-mail: [email protected]  1 RESUMO  No Brasil, assim como na maioria dos outros países, o sistema de irrigação por sulcos é um dos mais utilizados. Dessa forma, esta pesquisa objetivou avaliar a influência da lâmina requerida no desempenho desse sistema, para diferentes tipos de solo e comprimento de sulco. A análise de sensibilidade do desempenho foi desenvolvida mediante simulações do processo da irrigação por sulco, feitas pelo procedimento matemático hidrodinâmico do modelo SIRMOD (Surface Irrigation Simulation Model). Em todos os estudos de caso adotou-se a estratégia de manejo com vazão constante e a condição de irrigação adequada. As simulações foram realizadas em quatro tipos de solo, seis lâminas d’água e quatro comprimentos de sulco. Para os tipos de solo estudados observa-se que, no comprimento de sulcos de 100m, a eficiência de aplicação decresce à medida que a lâmina requerida aumenta, mas no sulco com comprimento de 250m ela aumenta sempre que a lâmina requerida também aumenta.  UNITERMOS: irrigação por sulcos, desempenho, lâmina requerida  AZEVEDO, C.A.V.; PORDEUS, R.V.; SILVEIRA, J.I.; LIMA, V.L.A. DANTAS NETO, J. INFLUENCE OF THE REQUIRED WATER DEPTH ON THE FURROW IRRIGATION PERFORMANCE  2 ABSTRACT  Considering the great using of the furrow irrigation system in Brazil as well as in most countries of the world, this research had the objective of evaluating the influence of the required water depth on the performance of that system, for different soil types and furrow lengths. The performance sensitivity analysis was developed through simulations of the furrow irrigation process performed by the hydrodynamic mathematical procedure of the SIRMOD model (Surface Irrigation Simulation Model). For all case studies, the continuous flow management strategy and the adequate irrigation condition were adopted. The studies were accomplished in four soil types, six required water depths and four furrow lengths. For the soil types studied, it is observed that in the 100m furrow length, theapplication efficiency decreases as the required water depth increases, but in the 250 m furrow length the application efficiency increases as the required water depth increases.  KEYWORDS: furrow irrigation, performance, required water depth 


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