scholarly journals The Study of Subsurface Land Drainage Optimal Design Model

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Ahmad Bakour ◽  
Zhanyu Zhang ◽  
Chengxin Zheng ◽  
Mohamed A. ALsakran ◽  
Mohamad Bakir
Keyword(s):  
Mathematical Model ◽  
Optimal Design ◽  
Computer Code ◽  
Land Drainage ◽  
Vertical Drainage ◽  
Pumping Stations ◽  
Study Results ◽  
Alternative Designs ◽  
The Mathematical Model

This paper focused on choosing the best design of subsurface land drainage systems in semiarid areas. The study presented three different soil layers with different hydraulic conductivity and permeability, all layers are below the drain level, and the permeability is increasing with depth. A mathematical model was formulated for the horizontal and vertical drainage optimal design. The result was a nonlinear optimization problem with nonlinear constraints, which required numerical methods for its solution. The purpose of the mathematical model is to find the best values of pipes and tubewells spacing, groundwater table drawdown, and pumps operating hours which leads to a minimum total cost of the subsurface drainage design. A computer code was developed in MATLAB environment and applied to the case study. Results show that the vertical drainage was economically better for the case study drainage network design. And the main factor affecting the mathematical model for both pipe and well drainage was the distance between pipes and tubewells. In addition, considering the lifespan of vertical drainage project, the optimal design involves the minimum possible duration of pumping stations. It is hoped that the proposed optimal mathematical model will present a design methodology by which the costs of all alternative designs can be compared so that the least-cost design is selected.

Modelling and Simulation of NO2 Dispersion Phenomenon in Atmosphere by Analytical-Experimental Methods

2008 ◽  
Vol 59 (10) ◽  
Author(s):  
Delia Perju ◽  
Harieta Pirlea ◽  
Gabriela-Alina Brusturean ◽  
Dana Silaghi-Perju ◽  
Sorin Marinescu
Keyword(s):  
Mathematical Model ◽  
Nitrogen Dioxide ◽  
Modeling And Simulation ◽  
Human Health ◽  
Experimental Methods ◽  
Negative Effects ◽  
Real Situation ◽  
Experimental Values ◽  
The Mathematical Model

The European laws and recently the Romanian ones impose more and more strict norms to the large nitrogen dioxide polluters. They are obligated to continuously improve the installations and products so that they limit and reduce the nitrogen dioxide pollution, because it has negative effects on the human health and environment. In this paper are presented these researches made within a case study for the Timi�oara municipality, regarding the modeling and simulation of the nitrogen dioxide dispersion phenomenon coming from various sources in atmosphere with the help of analytical-experimental methods. The mathematical model resulting from these researches is accurately enough to describe the real situation. This was confirmed by comparing the results obtained based on the model with real experimental values.

Multi-Object Multi-Discipline Probabilistic Design of High-Pressure Turbine Blade-Tip Radial Running Clearance

2013 ◽  
Vol 572 ◽  
pp. 551-554
Author(s):  
Wen Zhong Tang ◽  
Cheng Wei Fei ◽  
Guang Chen Bai
Keyword(s):  
Mathematical Model ◽  
High Pressure ◽  
Optimal Design ◽  
Mechanical System ◽  
High Accuracy ◽  
Probabilistic Design ◽  
High Pressure Turbine ◽  
Surface Method ◽  
Blade Tip ◽  
The Mathematical Model

For the probabilistic design of high-pressure turbine (HPT) blade-tip radial running clearance (BTRRC), a distributed collaborative response surface method (DCRSM) was proposed, and the mathematical model of DCRSM was established. From the BTRRC probabilistic design based on DCRSM, the static clearance δ=1.865 mm is demonstrated to be optimal for the BTRRC design considering aeroengine reliability and efficiency. Meanwhile, DCRSM is proved to be of high accuracy and efficiency in the BTRRC probabilistic design. The present study offers an effective way for HPT BTRRC dynamic probabilistic design and provides also a promising method for the further probabilistic optimal design of complex mechanical system.

scholarly journals Developing an Analytical Model and Computing Tool for Optimizing Lapping Operations of Flat Objects Made of Alloyed Steels

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1343 ◽  
Author(s):  
Tudor Deaconescu ◽  
Andrea Deaconescu
Keyword(s):  
Mathematical Model ◽  
Surface Roughness ◽  
Material Properties ◽  
Depth Of Cut ◽  
Operation Optimization ◽  
Abrasive Grains ◽  
Finishing Process ◽  
Real World Applications ◽  
The Mathematical Model

Lapping is a finishing process where loose abrasive grains contained in a slurry are pressed against a workpiece to reduce its surface roughness. To perform a lapping operation, the user needs to set the values of the respective lapping conditions (e.g., pressure, depth of cut, the rotational speed of the pressing lap plate, and alike) based on some material properties of the workpiece, abrasive grains, and slurry, as well as on the desired surface roughness. Therefore, a mathematical model is needed that establishes the relationships among the abovementioned parameters. The mathematical model can be used to develop a lapping operation optimization system, as well. To this date, such a model and system are not available mainly because the relationships among lapping conditions, material properties of abrasive grains and slurry, and surface roughness are difficult to establish. This study solves this problem. It presents a mathematical model establishing the required relationships. It also presents a system developed based on the mathematical model. In addition, the efficacy of the system is also shown using a case study. This study thus helps systematize lapping operations in regard to real-world applications.

Mathematical Model of Multi-Layer Wall with Phase Change Material and its Use in Optimal Design

2013 ◽  
Vol 649 ◽  
pp. 295-298
Author(s):  
Lubomir Klimes ◽  
Pavel Charvát ◽  
Josef Stetina
Keyword(s):  
Mathematical Model ◽  
Optimal Design ◽  
Phase Change ◽  
Phase Change Material ◽  
Control Volume ◽  
Operational Conditions ◽  
Volume Method ◽  
The Mathematical Model ◽  
Change Material

The paper deals with the mathematical model of the multi-layer wall containing the phase change material (PCM). The model utilizes the effective heat capacity method for modeling the latent heat of phase change and the control volume method is used for the discretization of the model. The utilization of the model is then demonstrated on the problem of the optimal design of the multi-layer wall with the PCM. The TMY2 data for the city of Brno were used in simulations as operational conditions. The main attention is aimed at the determination of the optimal thickness of the PCM layer for the multi-layer wall design with various thicknesses of the masonry.

scholarly journals Applied Mathematical Approach for Decision-Making in Building Plan Design

2018 ◽  
Vol 3 (9) ◽  
pp. 39
Author(s):  
Grit Ngowtanasuwan
Keyword(s):  
Mathematical Model ◽  
Mathematical Models ◽  
Publishing House ◽  
Unit Cost ◽  
Construction Cost ◽  
Model Unit ◽  
International Publishing ◽  
Plan Design ◽  
The Mathematical Model

This article presents a method for solving decision in building plan design by using a mathematical model (nonlinear programming). First objective is to formulate mathematical models for analysis in dividing rooms and dimensions in a building plan. Secondly, to calculate the dimensions and room sizes which have minimum construction cost. A case study of a condominium building plan was analyzed in this research. The results found application of the mathematical model was applicable. The mathematical models were formulated, the minimum construction cost was ฿723,000 (US$24,100) and usable area in the condominium was 67.5 m2 and followed the assigned design constraints.Keywords: Building plan design; Mathematical model; Unit cost;eISSN 2398-4295 © 2018. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open-access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. DOI:

scholarly journals A General Modeling Approach for Shock Absorbers: 2 DoF MR Damper Case Study

2021 ◽  
Vol 7 ◽  
Author(s):  
Jorge de-J. Lozoya-Santos ◽  
Juan C. Tudon-Martinez ◽  
Ruben Morales-Menendez ◽  
Olivier Sename ◽  
Andrea Spaggiari ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Degrees Of Freedom ◽  
Linear Models ◽  
Mr Damper ◽  
Shock Absorbers ◽  
Magneto Rheological ◽  
The Mathematical Model ◽  
Force Displacement ◽  
Standard Tests

A methodology is proposed for designing a mathematical model for shock absorbers; the proposal is guided by characteristic diagrams of the shock absorbers. These characteristic diagrams (Force-Displacement, Velocity-Acceleration) are easily constructed from experimental data generated by standard tests. By analyzing the diagrams at different frequencies of interest, they can be classified into one of seven patterns, to guide the design of a model. Finally, the identification of the mathematical model can be obtained using conventional algorithms. This methodology has generated highly non-linear models for 2 degrees of freedom magneto-rheological dampers with high precision (2–10% errors).

scholarly journals An Estimation of Dates Production Function in Karbala Governorate For The Agricultural Season 2020 (Al-jadual Al-gharby District A case Study)

2021 ◽  
Vol 923 (1) ◽  
pp. 012070
Author(s):  
Sadeq H. Hussein ◽  
Hayder Hamed Blaw
Keyword(s):  
Mathematical Model ◽  
Least Squares ◽  
Production Function ◽  
Returns To Scale ◽  
Ordinary Least Squares ◽  
Total Production ◽  
Logarithmic Function ◽  
The Mathematical Model

Abstract This study aimed to detect the most important factor that affects dates production. About 108 questionary forms collecttted palm orchard farmers in Karbala to estimate the dates production function in Karbala governorate for the agricultural season 2021 (the district of Al-jadual Al-Gharby). The study distributed those formmmsss for about 10% of the total palm orchards in Al-jadual Al-Gharby district of the holy governorate of Karbala. The study used the method of ordinary Least squares (OLS) to estimate the mathematical model of the function. The results showed that the double Logarithmic function in terms of its estimation of the estimated Coefficients by one unit leads to a corresponding change in the produced quality of dates and the same direction by 0.188 0.808) % respectively, and that the capital variable is more in fluently in production than the work variable. As for the total production elasticity (the sum of the partial elasticities of the resources used), which represents returns to scale, it amounted to about (0.996), which indicates a decrease in the return to scale.

Measurement and Calculation of Heat Exchanger Performance Using Film Method

Volume 3 ◽  
2004 ◽  
Author(s):  
Che´rif Bougriou ◽  
Rachid Bessai¨h ◽  
Kerstin Eckert ◽  
Mahfoud Kadja
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Computer Code ◽  
Method Of Calculation ◽  
Finned Tubes ◽  
The Mathematical Model ◽  
The Heat Transfer Coefficient ◽  
Film Method

In this paper, we present a method of calculation by partial or total condensation of the water vapor contained in the humid air, over the smooth or finned tubes-heat recupurators. This study presents an implantation of the film method in a computer code developed here. The mathematical model used is validated by our experimental approach, using tubes bundles in staggered and aligned arrangements. The heat transfer coefficient by convection around the fin is supposed too be constant. The computer code predicts the heat flux exchanged in a range of 20% and 5%, in wet and dry regime, respectively. The apparent heat transfer coefficient by condensation can exceed 10 times the value of the heat transfer coefficient. The mathematical model used is validated with the experimental data obtained in this study.

scholarly journals Estimating the Optimum Tilt Angles for South-Facing Surfaces in Palestine

Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 623 ◽  
Author(s):  
Ramez Abdallah ◽  
Adel Juaidi ◽  
Salameh Abdel-Fattah ◽  
Francisco Manzano-Agugliaro
Keyword(s):  
Mathematical Model ◽  
Solar Radiation ◽  
Tilt Angle ◽  
Peak Power ◽  
Horizontal Surface ◽  
Geographical Information ◽  
Solar Panels ◽  
Energy Gains ◽  
The Mathematical Model

The optimum tilt angle of solar panels or collectors is crucial when determining parameters that affect the performance of those panels. A mathematical model is used for determining the optimum tilt angle and for calculating the solar radiation on a south-facing surface on a daily, monthly, seasonal, semi-annual, and annual basis. Photovoltaic Geographical Information System (PVGIS) and Photovoltaic Software (PVWatts) is developed by the NREL (US National Renewable Energy Laboratory) are also used to calculate the optimum monthly, seasonal, semi-annual, and annual tilt angles and to compare these results with the results obtained from the mathematical model. The results are very similar. PVGIS and PVWatts are used to estimate the solar radiation on south-facing surfaces with different tilt angles. A case study of a mono-crystalline module with 5 kWP of peak power is used to find out the amount of increased energy (gains) obtained by adjusting the Photovoltaic (PV) tilt angles based on yearly, semi-annual, seasonal, and monthly tilt angles. The results show that monthly adjustments of the solar panels in the main Palestinian cities can generate about 17% more solar energy than the case of solar panels fixed on a horizontal surface. Seasonal and semi-annual adjustments can generate about 15% more energy (i.e., it is worth changing the solar panels 12 times a year (monthly) or at least 2 times a year (semi-annually). The yearly optimum tilt angle for most Palestinian cities is about 29°, which yields an increase of about 10% energy gain compared to a solar panel fixed on a horizontal surface.

An Integer Programming Approach to Optimize the Plantation in Order to Reduce Global Warming

2012 ◽  
Vol 548 ◽  
pp. 767-771 ◽  
Author(s):  
C. Vanlisuta ◽  
Suksan Prombanpong
Keyword(s):  
Mathematical Model ◽  
Linear Programming ◽  
Objective Function ◽  
Programming Model ◽  
Programming Approach ◽  
Profit Function ◽  
Carbon Credit ◽  
Integer Linear Programming Model ◽  
The Mathematical Model

The objective of this paper is to determine the number and species of trees to be planted in order to maximize a profit through an integer linear programming model. The mathematical model is developed in terms of the profit function. This objective function is therefore, a difference between carbon credit revenue and costs of plantation. The economical plants are only considered in the model. Consequently, fourteen different tree species are to be investigated. The objective function is subjected to several constraints i.e. planting area, carbon sequestration and so on. The planting envelope of each tree is assigned 4 by 4 meters. In this paper, the Eastern part of Thailand is considered the case study. It is found that three kinds of plants, Copper pod, Cananga, and Bullet wood are suitable for planting. A number of trees to be planted in 1600 square meter are twenty, thirty, and fifty plants respectively. The profit earned is of 12,112 $ per year in the next fifth year.

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