scholarly journals Urban Comprehensive Water Consumption: Nonlinear Control of Production Factor Input Based upon the C-D Function

2019 ◽  
Vol 11 (4) ◽  
pp. 1125 ◽  
Author(s):  
Kebai Li ◽  
Tianyi Ma ◽  
Tom Dooling ◽  
Guo Wei
Keyword(s):  
Water Supply ◽  
Production Function ◽  
Water Consumption ◽  
Water Demand ◽  
Demand Function ◽  
Production Factor ◽  
Urban Water ◽  
Urban Water Supply ◽  
Labor Input ◽  
Urban Water Demand

Utilizing the urban water demand function and the Cobb-Douglas (C-D) production function, an economic control model for the multi-input-multi-output (MIMO) nonlinear system was designed and implemented to describe urban comprehensive water consumption, where the urban water demand function was expressed as the product of the number of water users and per capita comprehensive water consumption, and the urban water supply function was expressed as a C-D production function. The control variables included capital investment and labor input for the urban water supply. In contrast to the Solow model, Shell model and aggregate model with renewable labor resources, the proposed model eliminated value constraints on investment and labor input in the state equations and hence avoided the difficulty in applying these models to urban water supply institutions. Furthermore, the feedback linearization control design (FLCD) method was employed to accomplish stability of the system. In contrast to the optimal control method, the FLCD method possesses an explicit solution of the control law and does not require the solution of a two-point boundary value problem of an ordinary differential equation, making the method more convenient for application. Moreover, two different scenarios of urban water consumption, one for the growth period and the other for the decline period, were simulated to demonstrate the effectiveness of the proposed control scheme.

scholarly journals Forecasting Urban Water Demand Using Cellular Automata

Water ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 2038
Author(s):  
Laís Marques de Oliveira ◽  
Samíria Maria Oliveira da Silva ◽  
Francisco de Assis de Souza Filho ◽  
Taís Maria Nunes Carvalho ◽  
Renata Locarno Frota
Keyword(s):  
Cellular Automata ◽  
Water Consumption ◽  
Water Demand ◽  
Water Resource Management ◽  
Transition Probability ◽  
Management Strategies ◽  
Weight Of Evidence ◽  
Annual Growth Rate ◽  
Urban Water ◽  
Urban Water Demand

Associating the dynamic spatial modeling based on the theory of cellular automata with remote sensing and geoprocessing technologies, this article analyzes what would be the per capita consumption behavior of Fortaleza-CE, located in the Northeast of Brazil, in 2017, had there not been a period of water scarcity between 2013 and 2017, and estimates the future urban water demand for the years 2021 and 2025. The weight of evidence method was applied to produce a transition probability map, that shows which areas will be more subject to consumption class change. For that, micro-measured water consumption data from 2009 and 2013 were used. The model was validated by the evaluation of diffuse similarity indices. A high level of similarity was found between the simulated and observed data (0.99). Future scenarios indicated an increase in water demand of 6.45% and 10.16% for 2021 and 2025, respectively, compared to 2017. The simulated annual growth rate was 1.27%. The expected results of urban water consumption for the years 2021 and 2025 are essential for local water resources management professionals and scientists, because, based on our results, these professionals will be able to outline future water resource management strategies.

scholarly journals Optimization of water reservoir volume in an urban water supply system

2021 ◽  
Author(s):  
Lucija Plantak ◽  
Bojan Đurin ◽  
Tatjana Džeba ◽  
Sara Dadar
Keyword(s):  
Water Supply ◽  
Water Consumption ◽  
Water Reservoir ◽  
Supply System ◽  
Water Supply System ◽  
Urban Water ◽  
Urban Water Supply ◽  
Functional Relationships ◽  
Reservoir Volume ◽  
Water Pumping

In this paper, the water pumping regime, as well as the water consumption regime with regard to the required quantities and the example of water consumption, with an emphasis on changes in water volume, are examined. This aims to show the functioning of the regime of water consumption, water pumping, as well as finding functional relationships between the mentioned sizes and the volume of the water reservoir. The analysis focuses on questions such as how and in what way, changes in the onset and duration of pumping, as well as different water consumption regimes affect the size of the reservoir volume. The entire analysis in this paper was done to develop a scientifically innovative, but also applicable mathematical model, which is a contribution to the profession and a good basis for further scientific research to improve the operation of the urban water supply system.

MATHEMATICAL MODELLING OF URBAN WATER SUPPLY SYSTEM CRISIS

Engevista ◽  
2011 ◽  
Vol 13 (1) ◽  
Author(s):  
Marco Antonio Almeida de Souza ◽  
Welitom Ttatom Pereira da Silva
Keyword(s):  
Water Supply ◽  
Conceptual Model ◽  
Urban Environment ◽  
Influencing Factors ◽  
Water Consumption ◽  
Water Availability ◽  
Supply System ◽  
Water Supply System ◽  
Urban Water ◽  
Urban Water Supply

Purpose – The chaotic growth of cities results in numerous problems related to public health and urban environment. One of these problems is the crisis in urban water supply systems. The objective of this paper is to develop a mathematical model for the water supply system crisis in urban environment (WSC) able to tackle with the ambiguity of the real available data.Design/methodology/approach – The applied methodology comprises the following steps: (1) identification of the influencing factors in WSC; (2) proposal of a conceptual model for WSC description; (3) gathering and simulation of the necessary and available data; (4) optimization of the conceptual model parameters; and (5) verification of the proposed model performance.Findings – The results indicated that there is a great amount of influencing factors in WSC (showed in the complete text); the conceptual model that was developed is composed by two others partial models ( ). The first partial model explained the water consumption ( ),and the second partial model explained the water availability ( ), in which functions are related to influencing factors in water consumption (i.e. temperature, relative humidity, rainfall, revenues collected, unemployment indicator), and functions are related to the influencing factors in water availability (i.e. total water-loss, intermittence in water supply system). The proposed conceptual model has showed good agreement to the simulated data.Originality/value – The paper is among the first works to describe a WSC model and to analyze the possibility of applying fuzzy logic to deal with the ambiguity of the real data. The water supply crisis in urban environments was adequately modelled.

Urban Water Consumption Forecasting Based on Projection Pursuit

2012 ◽  
Vol 542-543 ◽  
pp. 1334-1338
Author(s):  
Zhao Han Wang ◽  
Chang Guo Xuan ◽  
Qiang Fu
Keyword(s):  
Water Supply ◽  
Water Consumption ◽  
Projection Pursuit ◽  
Nonlinear Problems ◽  
Supply System ◽  
Forecasting Model ◽  
Urban Water ◽  
Urban Water Supply ◽  
Analysis Method ◽  
New Approach

In order to meet energy conservation and utilization optimization in urban water supply system and ensure water supply time and efficiency, we adopted the projection pursuit autoregression method to establish the projection pursuit autoregression water consumption forecasting model, combined the projection pursuit technique and time-series autoregression analysis method, and better solved the abnormal and nonlinear problems in urban water consumption. The practice proves that the forecasting precision of this model reaches the engineering requirements, and it provides a new approach for water consumption forecasting and analysis.

scholarly journals Dynamic Modeling and Simulation of Urban Domestic Water Supply Inputs Based on VES Production Function

Mathematics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 89
Author(s):  
Kebai Li ◽  
Zhilei Ding
Keyword(s):  
Water Supply ◽  
Production Function ◽  
Water Demand ◽  
Early Stage ◽  
Supply And Demand ◽  
Labor Input ◽  
Domestic Water ◽  
Straight Line ◽  
Per Capita ◽  
Domestic Water Supply

The Gompertz growth curve is used to describe the urban water population, the linear function is used to represent the per capita disposable income, and the domestic water demand is described combined with the factors of population, income, and the water-saving consciousness. The VES production function is used to describe the production function of the domestic water supply. Combined with system dynamics, the supply and demand management model of urban domestic water in Jiangsu province, China, is developed. The process of water supply investment and labor input in the urban domestic water system is studied with two depreciation methods: the straight-line depreciation method and the sum of years digits method. In the case that the water consumption population is expected to decline, four water demand scenarios composed of different per capita disposable income and the growth rate of water-saving consciousness are investigated. Investment and labor input are taken as control variables to conduct water supply and demand simulations for the four scenarios. The results show that the control schemes in all four scenarios reach a balance between water supply and demand. Moreover, the investment of the sum of years digits method is larger than that of the straight-line depreciation method in 2005–2019 but less than that of the straight-line depreciation method in 2020–2034. The sum of years digits method has the characteristics of more depreciation in the early stage and less depreciation in the later stage, which is conducive to timely compensation for the large loss of fixed assets in the early stage.

scholarly journals Fuzzy Modeling of Urban Water Supply Crisis

2021 ◽  
Author(s):  
Welitom Ttatom Pereira da Silva ◽  
Marco Antonio Almeida de Souza
Keyword(s):  
Water Supply ◽  
Conceptual Model ◽  
Influencing Factors ◽  
Water Consumption ◽  
Model Performance ◽  
Real Data ◽  
Model Parameters ◽  
Urban Water ◽  
Urban Water Supply ◽  
Proposed Model

The chaotic growth of cities results in numerous problems related to public health and urban environment. One of these problems is the urban water supply system crisis. This research aims to develop a mathematical model for urban water supply crises (UWC) able to deal with the ambiguity of the real available data. The applied methodology comprises the following steps: (i) identifying the influencing factors in UWC; (ii) proposing a conceptual model for the description of UWC; (iii) collecting and simulating the necessary and available data; (iv) optimizing the conceptual model parameters; and (v) verifying the proposed model performance. The results indicate that there are many influencing factors in UWC. The model developed comprises two parts or two sub-models. The first sub-model explains water consumption, and the second sub-model explains water availability. In the first sub-model, the functions are related to the factors that influence water consumption. In the second sub-model, the functions are related to the factors that influence the availability of water. This research also aims to analyze the possibility of applying Fuzzy Logic to deal with the ambiguity of real data. It was concluded that, with the proposed model, the UWC was modeled appropriately. The model proposed can help to predict the impact of actions such as reducing losses, reducing pressure on the water supply network and intermittent supply on the intensity of water crisis cases in cities.

Sign in / Sign up

Export Citation Format

Share Document