A Model for Reducing the Cost of Refueling in a Flight Route Problem With Discounted Fuel Prices

2021 ◽  
pp. 1-27
Author(s):  
Said Ali Hassan ◽  
Miral Hossam Khodeir
Keyword(s):  
Mathematical Model ◽  
Total Cost ◽  
Fuel Prices ◽  
Route Problem ◽  
Commercial Airline ◽  
Flight Route ◽  
The Cost ◽  
The Mathematical Model ◽  
Implementing Strategies

Acquiring and purchasing fuel represents a significant part of operating and managing expenses for an airline, so commercial airline companies are implementing strategies for minimizing costs of fuel for their flight routes. A nonlinear mathematical model for the airline refueling problem is presented to minimize the total cost in a flight route problem. The model is enhanced to include possible discounts in fuel prices, which are performed by adding dummy variables and some restrictive constraints, or by fitting a suitable function that relates prices to the purchased amounts. The obtained fuel plan explains exactly the amounts of fuel to be purchased from each airport in the route. A case study is introduced for a certain flight rotation in a domestic US air aviation company. The mathematical model including stepped discounted fuel prices is formulated, and the results show that introducing the discounted fuel prices dramatically change the strategy of fuel purchase amounts in the aircraft flight problem.

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.

scholarly journals An Optimized Mathematical Model for Items Supplies Planning of a Logistic System

2016 ◽  
Vol 10 (10) ◽  
pp. 133
Author(s):  
Mohammad Ali Nasiri Khalili ◽  
Mostafa Kafaei Razavi ◽  
Morteza Kafaee Razavi
Keyword(s):  
Mathematical Model ◽  
Mixed Integer ◽  
Logistics System ◽  
Proposed Model ◽  
Multiple Objective Decision Making ◽  
System Requirements ◽  
Purchasing Logistics ◽  
The Cost ◽  
The Mathematical Model ◽  
First Time

Items supplies planning of a logistic system is one of the major issue in operations research. In this article the aim is to determine how much of each item per month from each supplier logistics system requirements must be provided. To do this, a novel multi objective mixed integer programming mathematical model is offered for the first time. Since in logistics system, delivery on time is very important, the first objective is minimization of time in delivery on time costs (including lack and maintenance costs) and the cost of purchasing logistics system. The second objective function is minimization of the transportation supplier costs. Solving the mathematical model shows how to use the Multiple Objective Decision Making (MODM) can provide the ensuring policy and transportation logistics needed items. This model is solved with CPLEX and computational results show the effectiveness of the proposed model.

scholarly journals Direct Cost of Reprocessing Cotton-woven Surgical Drapes: a Case Study

2015 ◽  
Vol 49 (3) ◽  
pp. 488-494 ◽  
Author(s):  
Mariana Fexina Tomé ◽  
Antônio Fernandes Costa Lima
Keyword(s):  
Human Resources ◽  
Direct Cost ◽  
Financial Resources ◽  
Average Total Cost ◽  
Descriptive Case Study ◽  
Total Cost ◽  
Advantages And Disadvantages ◽  
Cost Of Materials ◽  
The Cost

OBJECTIVE Identify the direct cost of reprocessing double and single cotton-woven drapes of the surgical LAP package. METHOD A quantitative, exploratory and descriptive case study, performed at a teaching hospital. The direct cost of reprocessing cotton-woven surgical drapes was calculated by multiplying the time spent by professionals involved in reprocessing the unit with the direct cost of labor, adding to the cost of materials. The Brazilian currency (R$) originally used for the calculations was converted to US currency at the rate of US$0.42/R$. RESULTS The average total cost for surgical LAP package was US$9.72, with the predominance being in the cost of materials (US$8.70 or 89.65%). It is noteworthy that the average total cost of materials was mostly impacted by the cost of the cotton-woven drapes (US$7.99 or 91.90%). CONCLUSION The knowledge gained will subsidize discussions about replacing reusable cotton-woven surgical drapes for disposable ones, favoring arguments regarding the advantages and disadvantages of this possibility considering human resources, materials, as well as structural, environmental and financial resources.

MATHEMATICAL MODELLING FOR FISH FEED FORMULATION OF MYSTUS NEMURUS SP. CATFISH: OPTIMIZING GROWTH AND NUTRIENTS REQUIREMENTS

2018 ◽  
Vol 80 (6) ◽  
Author(s):  
Nur Aidya Hanum Aizam ◽  
Rabiatul Adawiyah Ibrahim ◽  
Raphael Lee Kuok Lung ◽  
Pang Yen Ling ◽  
Aidilla Mubarak
Keyword(s):  
Mathematical Model ◽  
Nutrient Composition ◽  
Future Research ◽  
Fish Feed ◽  
Research Directions ◽  
Feed Formulation ◽  
Future Research Directions ◽  
The Cost ◽  
The Mathematical Model ◽  
Mystus Nemurus

This study integrates mathematical model in the plan of producing a fish feed formulation by reducing the total cost without neglecting the nutrient requirements. This study focuses on producing the perfect combination of fish feed for Mystus nemurus sp. catfish in different stages of life. The mathematical model developed will consider their required nutrients in each stage, the cost of each ingredient and the amount of nutrients to be consumed (nutrient composition of fish feed ingredients). This research employs AIMMS mathematical software to assist with the computation. The results from this study obtain a much better combination of different ingredients compared to available commercial pellets in terms of nutrient composition and production cost. The combinations yield much cheaper costs yet boosts up the nutrient consumptions, which is an eye-opener for independent local fish farmers. Thorough discussion on utilizing the results with future research directions will also be included.

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.

Measures to Relieve the Stress of Water

2013 ◽  
Vol 361-363 ◽  
pp. 636-639 ◽  
Author(s):  
Shi Kai Duan ◽  
Guo Shi Shen ◽  
Zhen Dong Shan ◽  
Yan Dong ◽  
Kai Zheng ◽  
...  
Keyword(s):  
Water Resources ◽  
Water Shortage ◽  
The United States ◽  
Three Solutions ◽  
Total Cost ◽  
Pros And Cons ◽  
Water Strategy ◽  
The Cost ◽  
Significant Regional Difference

In order to develop realistic water resources strategy, we initially analyze the situation of water resources in the United States which present a significant regional difference. Then on the basis of previous studies, we propose the cost formulas of water storage, movement and desalinization. By analyzing the practical application, along with pros and cons of the above three solutions accordingly, we consider that a comprehensive utilization of these measures will be the best water strategy for America to solve the water shortage problem. Later we apply the conclusion to a case study of Southern California, we propose an optimization model which aims to minimize the total cost of the water strategy, and then use Lingo to solve the problem. Results show that 5.946 billion cubic meters of water by transferring is the best way to make up for the water use gap in 2025 and the total cost is 2.94 billion dollars. Finally, we summarize the strengths and weaknesses of our paper. What needs to be emphasized is that our model can also be adapted into the analysis of other states, which shows great flexibility.

Performance Analysis of Parallel Feed LT-MED Desalination System with Thermal Vapor Compressor

2011 ◽  
Vol 347-353 ◽  
pp. 3058-3063 ◽  
Author(s):  
Xiao Hua Liu ◽  
Guo Jian Cao ◽  
Sheng Qiang Shen ◽  
Guang Bin Zhao
Keyword(s):  
Mathematical Model ◽  
Flow Resistance ◽  
Tube Bundle ◽  
Steam Temperature ◽  
Heating Steam ◽  
Temperature Loss ◽  
Output Ratio ◽  
Actual Operation ◽  
The Cost ◽  
The Mathematical Model

This paper presents a theoretical analysis on parallel feed LT-MED desalination system with thermal vapor compressor which is helpful to the design and operation of such kind of seawater desalination plant. The mathematical model of a parallel feed LT-MED desalination system with thermal vapor compressor (TVC) is developed on the basis of the mass and energy conservation equations. In the model, the temperature loss is considered caused by the boiling point elevation (BPE) of seawater and the steam flow resistance is also included caused by flowing through tube bundle demisters and pipelines between adjacent evaporators. The property parameters of seawater are taken as the functions of temperature and concentration. A computer program is drawn up to solve the mathematical model. The calculation is based on the system with rated water production 3000 t/d. Taking actual operation into account, the influence of heating steam temperature of the first effect and entrained steam position of TVC on system performance are analyzed. The results show that when other relative parameters are fixed, the gained output ratio (GOR) and the total area of evaporators change slightly with the increasing of the heating steam temperature of first effect under the calculation condition of this paper. The results also demonstrate that there exist suitable entrained steam positions of TVC for the cost of water.

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.

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