ANNs have been used as black-box simplified models in several water resources problems. The black-box type flood forecasting models can be considered as pattern mappings for input-output data sets. Multilayer perceptron (MLP) network (Rumelhart et at., 1986) is usually used for pattern mapping problems and consists of the input layer, one or more hidden layers of computational nodes (neurons), and an output layer of computational nodes. In a feedforward structure, data flow only in one direction. A neuron in a particular layer receives all input from the preceding layer and transmit the values to the succeeding layers of processing element. The schematic representation of the feedforward MLP network designed according to the Muskingum equation (Eq. 4) is shown in Fig. 1. It has one input layer, one hidden layer and one output layer respectively. Each node in a layer is connected to all nodes in the successive layer, and the neurons in the same layer are not connected each other. The data transferred from one neuron to another through the connections are controlled by the weights. The sum of the product of inputs (x) and their weights (w) minus bias (b) leads to a net as follows: net = ∑▒〖x_i .w_i 〗 - b (12)
Then, the output of a neuron, f (net) is decided by an activation function that determines a response of the node to the input signal it receives. In order to generate an output vector, a training (learning) process is used to find optimal weight matrices and bias vectors that minimize a predetermined error function (E) which is the sum of squares error given as follows.
E =∑_(p=1 )^p▒∑_(i=1)^N▒〖 (y_i-t_i)〗^2 (13)
Here, ti and yi represent the target (observed outflow, O_(t+∆t)) and output (predicted outflow...
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...to its important role in the country's social economy. Severe floods hit the Chindwin basin every year at one place or another due to high rainfall intensities during the southwest monsoon. Since 1965 flood occurrences in the Chindwin basin have been the highest in July and August contributing to 72% of the total number of floods in the basin. In this study, reported floods of two hydrometric stations, namely Homalin and Mawlaik, were considered. The length of the reach from upstream (Homalin) to downstream (Mawlaik) is 114km. According to the basin topography, the reach slope is about 0.0003, which is relatively mild. A flood wave is subjected to translation and reservoir actions during its passage through natural rivers and hydrologic methods are properly used in case the reservoir action dominates the translation action for rivers with a mild slope (Das, 2009).
A major flood on any river is both a long-term and a short-term event, particularly any river basin where human influence has exerted "control" over the ri...
Moore, J. R., Bell, A. V., Jones, A. D., 2005. Forecasting for flood warning. C.R Geoscience 337, 203-217.
One issue facing my locality is constant, yearly flooding that disrupts much of Glenville and the entire county. The Mayor of Glenville, Dennis Fitzpatrick, mentioned in an interview with me that “almost every year major flooding occurs,” and as someone who has lived near Glenville my entire life, I have also noticed the major issue of flooding as well. In Glenville, almost every ten years there is a major flood event that disrupts businesses and schools, while leaving much of the town with a mess to clean up afterwards. This is a pricey burden for a small town, and one that puts more and more local business at the risk of closing permanently. Once, my grandmother had
"Flood Stories from Around the World." Flood Stories from Around the World. N.p., n.d. Web. 04 May 2014.
“Flood” by Daniel Alarcón focuses on a town that is “flooded” with gang conflicts an the gangs determine the townspeople’s fate. The child narrator and the rest of the children in “Flood” are paradoxical to the usual portrayal of children. In “Flood” the children clearly have the “young gangster” in them. Whether the characters recognize themselves as gang members or innocent civilians, the gangs and their ongoing conflict and disagreements rule part of the characters everyday lives. So, the setting of “Flood” has a large influence and authority over the character’s lives.
Rhine Flooding Case Study Introduction: - The River Rhine is one of Europe's largest and most used waterways. The source of this great river can be found in the Swiss Alps, where it stretches 1,320km until it flows out into the Dutch North Sea. The Rhine has a long history of intense flooding and recent devastating floods in the 1990's have caused considerable damage and are well remembered by the local population. [IMAGE] Causes: - The causes of these forceful floods can be traced back to a number of different things including human factors such as deforestation, the greenhouse effect (this is show by the facts stating the 1°C temperature rise in southern Germany and the winter precipitation in the Rhine catchment increasing by 40%) and the straightening of the Rhine for commercial purposes.
[7] K. Anil Jain, Jianchang Mao and K.M. Mohiuddi, 1996. “Artificial Neural Networks: A Tutorial”, IEEE Computers, pp.31-44.
Flooding is an ongoing challenge in regional Victoria and it is expected to affect Victoria every 10-20 years. Victoria consists of 39 drainage basins and each of the basins comprises of rivers and streams (Comrie, 2011, pp.17). These rivers and streams are susceptible to flooding, which may impact various regional towns and communities within close proximity to water courses (Comrie, 2011, pp.17). The discussion of flooding is vital, as it is the most frequent occurring natural hazard, which affects approximately 520 million people per year Moore et al.2012, pp.1). Additionally, flooding is responsible for the lives of approximately 25,000 people every year and cost the global economy approximately $50- 60 billion per year (Moore et al.2012,
The purpose of this paper is to explain the advances being made in technology and algorithms in helping advance the accuracy of forecasting. It will contrast the forecasting methods of several decades ago with forecasting methods in use today. In discussing how errors can accumulate over time and providing simple mathematical formulas as examples, this paper intends to show how the repetition of minor errors can affect the accuracy of weather predictions.
So yearly floods spred deposits of rich soil over a wide area. However, the floods along the Indus were unperdictable The rivers sometimes changed course.
In this essay I aim to find out the ways in which they affect the
A Flood Hydrograph and the Factors That Affect its Form A flood hydrograph is a graph of two axis, 'discharge' and 'time'. Plotted on the graph is the amount of discharge over a period of time. By looking at a hydrograph, a lot of information and data can be gathered about the river, the precipitation, the surrounding area and vegetation etc. The gradient, height and length of a line can tell you a lot of this information. There are many different factors that can affect the appearance and shape of a hydrograph.
Gonzales, M. E. Q. Neural networks and Mental Representation: An essay on Harmony and Rationality. In: Trans/ Form/Ação, São Paulo, v. 14, p.93-108, 1991.
First and foremost, Kaeng Sua Ten dam cannot successfully relieve flood, reduce drought or even generate electricity. In order for the dam to be able to control floods, it must be able to store a large volume of the water. Hence, the reservoir must be empty to store sufficient floodwaters. However, it is not possible. Kaeng Sua Ten is a medium-sized dam, which has a capacity of around one billion cubic meters of water. It has a certain amount of water at all time to generate electricity (Eamwiwatkit, 1996). This means that the dam is unable to aid the local during the period of drought. The water is not supp...
Singh, Y. & Chauhan, A. (2009). Neural networks in data mining. Journal of Theoretical and