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31.
Coupling GIS with Hydrologic and Hydraulic Flood Modelling 总被引:6,自引:1,他引:5
Nunes Correia Francisco Castro Rego Filipe Da Grača Saraiva Maria Ramos Isabel 《Water Resources Management》1998,12(3):229-249
Geographic Information Systems (GIS) have been recognised as a powerful means to integrate and analyse data from various sources in the context of comprehensive floodplain management. As part of this comprehensive approach to floodplain management, it is very important to be able to predict the consequences of different scenarios in terms of flooded areas and associated risk. Hydrologic and hydraulic modelling plays a crucial role and there is much to gain in incorporating these modelling capabilities in GIS. This is still a rather complex task and research is being done on the full integration of these models. Interfacing between these models and GIS may be a very efficient way of overcoming the difficulties and getting very good results in terms of engineering practice. This paper presents results based on the use of Intergraph GIS coupled with Idrisi GIS. Using these two systems substantially increased the flexibility of using GIS as a tool for flood studies. A lumped (XSRAIN) and a distributed (OMEGA) hydrologic models were used to simulate flood hydrographs. The well known HEC-2 Hydraulic model was used to compute flooded areas. These models were applied in the Livramento catchment with very good results. The computation of flooded areas for different flood scenarios, and its representation in GIS, can be used in the assessment of affected property and associated damages. This is a very useful GIS-based approach to floodplain management. 相似文献
32.
Temperature, thermal efficiency, and gradient performance from two seawater-SZ solar ponds 总被引:1,自引:0,他引:1
This paper presents 10 months of experience with two seawater-SZ (Storage Zone) solar ponds operated as a source of warm seawater which could have been used in an adjacent mariculture facility. Observations and extensive temperature, gradient and efficiency data are presented. This work demonstrated operation of and heat extraction from seawater-SZ solar ponds over a much longer interval than in previous work. It confirmed that seawater-SZ solar ponds can consistently give useful temperature elevations. A few phenomena not characteristic of conventional solar ponds were identified and are discussed. 相似文献
33.
The effects of cooking temperature, time and temperature of brine-salting, and temperature of ripening on the behavior of Enterobacteriaceae in Manchego cheese were studied. Fifty lots of cheese from raw ewe's milk manufactured and ripened under different conditions were investigated throughout a 60-day ripening period. Differences in pH values due to temperature-dependent whey retention accounted for the effect of cooking temperature on coliform and fecal coliform counts. Temperature of brine-salting had no effect on Enterobacteriaceae counts, but a significant effect of salting time on Enterobacteriaceae and fecal coliform counts was detected. Ripening temperature was the manufacturing variable with greatest influence (P<.01) on Enterobacteriaceae and coliform counts during the whole curing period. 相似文献
34.
Summary Poly(propylene oxide), PPO, obtained using diphenylzinc, Ph2Zn, and using the diphenylzinc-water system at various molar ratios H2O/Ph2Zn, were studied through 1H NMR and IR spectroscopy establishing that the polymerization initiates by coordition of propylene oxide (PO) to a terminal zinc atom of the active species followed by consecutive insertions of PO units at this zinc atom. The PPO obtained showed Ph-and HO-, HO-and HO-end-groups depending on the molar ratio H2O/Ph2Zn used, and also HO-and PhO-end-groups when oxygen was present in the polymerization system. 相似文献
35.
36.
Marques R. Rafii-El-Idrissi R. Mesa F. Medina F. 《Microwave Theory and Techniques》2002,50(8):1935-1941
The propagation of leaky forward magnetostatic (MS) volume waves along ferrite-loaded microstrip and slot lines is analyzed. This phenomenon is studied by means of a numerical approach based on the residue calculus technique because of its good numerical convergence and stability. The proposed method allows for a quick and accurate computation of the phase and attenuation constants of the leaky MS modes. A comparative analysis between both microstrip lines and slot lines is carried out, and some new physical effects, such as MS resonances in the radiation loss, are reported. The advantages of the proposed method of analysis over other numerical methods, such as Galerkin's or moment methods, are also discussed. 相似文献
37.
Vicente Rodríguez Montequín Francisco Ortega Fernández Nicolás Abajo de Martínez Juan Antonio González Rodríguez 《JOM Journal of the Minerals, Metals and Materials Society》2002,54(7):46-50
This research summary discusses the application of neural networks, evolutionary strategies, and other artificial intelligence
techniques in the modeling and optimization of the models used for temperature, rolling force, and torque calculation in heavy
plate milling. 相似文献
38.
38MnSiVS5 steel is similar to 38MnVS6 steel (EN), the difference being the addition of a small Ti content. Typical Ti and Al contents in the chemical composition of 38MnSiVS5 steel are Ti=0.020 and Al=0.035 mass%. Both elements combine easily with nitrogen, especially Ti, and it has been observed that relatively high Al levels are harmful for austenite grain size control at reheating temperatures. In this work 38MnSiVS5 steel is used to manufacture a large number of castings, varying only the Ti and Al contents and obtaining ingots with a different Ti/Al ratio in each case. The results show that abnormal growth of the austenitic grain occurs irrespective of the Ti and Al contents, due fundamentally to the partial dissolution and coarsening of TiN precipitates. However, the steels with high Al contents present worse behaviour due to the formation of a second type of precipitates, namely AIN, which quickly dissolve between 1000 and 1100°C, causing a drastic decline in local pinning forces that gives rise to more pronounced abnormal growth of the affected grains. 相似文献
39.
The Steady radial distribution of chemical species in a wire‐to‐cylinder ozone generator filled with pure oxygen has been computed by applying four different plasma chemistry models of increasing complexity. The most complete model considers ten species (e, O2 +, O2 ?, O3 ?, O?, O2, O2(1Δg), O2(1∑g +), O and O3) and 79 reactions, including ionization by electron impact, electron attachment and detachment, electron-ion recombination, charge transfer, etc. The chemical model is coupled with the electrical model through Poisson's equation. The spatially averaged ozone density has been computed as a function of the current intensity and compared with the experimental values obtained by UV spectroscopy. 相似文献
40.
Edna R Meza‐Escalante Anne‐Claire Texier Flor Cuervo‐López Jorge Gómez Francisco J Cervantes 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(3):372-377
BACKGROUND: Many industrial discharges, such as those generated from petrochemical refineries, contain large amounts of sulfurous, nitrogenous and organic contaminants. Denitrification has emerged as a suitable technology for the simultaneous removal of these pollutants in a single reactor unit; however, more evidence is demanded to clarify the limitations of denitrification on the simultaneous removal of sulfide and phenolic contaminants and to optimize the biological process. The aim of this study was to evaluate the capacity of a denitrifying sludge to simultaneously convert sulfide and p‐cresol via denitrification. RESULTS: Sulfide was the preferred electron donor over p‐cresol, imposing a 5 h lag phase (required for complete sulfide removal) on organotrophic denitrification. Addition of sulfide (20 mg S2? L?1) to p‐cresol‐amended denitrifying cultures also decreased the reduction rate of nitrate and nitrite, as well as the production rate of nitrogen gas. Nitrite reduction rate was the most affected step by sulfide, decreasing from 35 to 21 mg N (g VSS d)?1. A synergistic inhibitory effect of nitrate and sulfide was also observed on nitrite reduction. Despite the effects of sulfide on the respiratory rates monitored, complete removal of nitrate, sulfide and p‐cresol could be achieved after 48 h of incubation. CONCLUSION: Our results suggest that simultaneous removal of sulfide and p‐cresol could be achieved in denitrifying reactors, but a large hydraulic residence time may be required to sustain an efficient process due to inhibitory effects of sulfide. Copyright © 2008 Society of Chemical Industry 相似文献