scholarly journals Improving Air Transportation by Using the Fuzzy Origin–Destination Matrix

Mathematics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1236
Author(s):  
Vladimir Sudakov
Keyword(s):  
Fuzzy Numbers ◽  
Air Transportation ◽  
Air Travel ◽  
New Methods ◽  
Maximum Value ◽  
Fuzzy Ranking ◽  
Regional Airports ◽  
The Given ◽  
Support Decision Making ◽  
The Membership Function

The work is devoted to the development of new methods and algorithms to support decision making when planning air travel using uncertainties in the form of fuzzy numbers. The proposed approach makes it possible to define rational methods of choice: how to change the transport graph to better meet the needs of the population. This is particularly relevant in the context of the reduced demand for air travel caused by the pandemic and the need to switch from large to smaller aircraft types. The problem is solved by restoring the fuzzy origin–destination matrix of current statistics on air traffic between airports. The problem is that we do not know what proportion of passengers moving between the specified points are forced to use large transport hubs as intermediate destinations. To determine the validity of the origin–destination matrix, we build a number of optimization models to determine fuzzy intervals and search for correspondence with the maximum value of the membership function. Algorithmic and software search for the fuzzy origin–destination matrix and fuzzy ranking of potentially promising routes are developed. The perspective of the given approach is shown by an example of a task concerning a choice of new routes between regional airports.

scholarly journals A New Method to Support Decision-Making in an Uncertain Environment Based on Normalized Interval-Valued Triangular Fuzzy Numbers and COMET Technique

Symmetry ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 516 ◽  
Author(s):  
Shahzad Faizi ◽  
Wojciech Sałabun ◽  
Samee Ullah ◽  
Tabasam Rashid ◽  
Jakub Więckowski
Keyword(s):  
Decision Making ◽  
Fuzzy Numbers ◽  
Simple Problem ◽  
Triangular Fuzzy Numbers ◽  
Topsis Method ◽  
Rank Reversal ◽  
Mcdm Method ◽  
Interval Valued ◽  
Support Decision Making ◽  
The Membership Function

Multi-criteria decision-making (MCDM) plays a vibrant role in decision-making, and the characteristic object method (COMET) acts as a powerful tool for decision-making of complex problems. COMET technique allows using both symmetrical and asymmetrical triangular fuzzy numbers. The COMET technique is immune to the pivotal challenge of rank reversal paradox and is proficient at handling vagueness and hesitancy. Classical COMET is not designed for handling uncertainty data when the expert has a problem with the identification of the membership function. In this paper, symmetrical and asymmetrical normalized interval-valued triangular fuzzy numbers (NIVTFNs) are used for decision-making as the solution of the identified challenge. A new MCDM method based on the COMET method is developed by using the concept of NIVTFNs. A simple problem of MCDM in the form of an illustrative example is given to demonstrate the calculation procedure and accuracy of the proposed approach. Furthermore, we compare the solution of the proposed method, as interval preference, with the results obtained in the Technique for Order of Preference by Similarity to Ideal solution (TOPSIS) method (a certain preference number).

ANALYSIS OF ECONOMIC ACTIVITY OF REGIONAL AIRPORTS OF FRANCE AND REGIONAL AIRPORTS OF THE CENTRAL FEDERAL DISTRICT: DEVELOPMENT OF LOW-COST AIRLINES DESTINATIONS AS A KEY FACTOR IN THE PASSENGER TRAFFIC GROWTH

2021 ◽  
Vol 1 (195) ◽  
pp. 75-87
Author(s):  
V.V. Rublev ◽  
Keyword(s):  
Low Cost ◽  
Federal District ◽  
Air Transportation ◽  
Minimal Impact ◽  
National Budget ◽  
Passenger Traffic ◽  
Central Federal District ◽  
Route Network ◽  
Key Factor ◽  
Regional Airports

The article presents an analysis of the activities of regional airports in France in 2019. The growth of passenger traffic was observed in those airports that actively developed cooperation with budget airlines, increasing the number of destinations in the route network. Regional airports in France, whose route network structure did not expand in 2019, showed a slight decrease in passenger traffic (from –0.1% to –3%). The first and only experimental regional airport in France (city of Beziers), handling flights of only one budget airline, Ryanair, showed an increase in passenger traffic by 14.5% in 2019. The share of routes of budget airlines in the structure of the route network of regional airports in France is quite high. The key problems of regional airports in Russia are the low passenger traffic and the underdeveloped route network. Due to the presence of the only national budget airline "Pobeda" on the market and the minimal impact on the segment of budget air transportation of foreign airlines, the share of budget air transportation destinations in the structure of regional airports of the Russian Federation continues to remain at an extremely low level. 2019 showed a record growth in passenger traffic at regional airports in the Central Federal District (an increase from +2.8% to +262%, with the exception of Tambov Airport, whose passenger traffic fell by 57.4%), which indicates an increase in demand and the need to expand the route network of regional airports. On the example of the Voronezh airport, a model for the development of low-cost airline destinations is presented.

scholarly journals INTEGRATED SYNOPTICAL METHOD FOR CALCULATING ASSIMILATION CAPACITY OF SEA WATERS

2017 ◽  
pp. 115-120
Author(s):  
Hikmat Hamid oglu Asadov ◽  
Sima Ajdar gizi Askerova
Keyword(s):  
Sea Water ◽  
Water Masses ◽  
Optimum Regime ◽  
Optimization Task ◽  
Maximum Value ◽  
Long Time ◽  
Negative Effect ◽  
Optimum Order ◽  
Assimilation Capacity ◽  
The Given

Pollution of sea waters is one of major attributes of coastal industrial centers and the norming of such emissions is one of major countermeasures. The assimilation capacity of sea waters is a major factor relevant at norming and planning of outflows into sea waters. At present time the synoptical method has been developed, which doesn’t require carrying out long time and repeated observing of the level of pollution of sea waters. This method has formed the basis for developing the integrated synoptical method for calculating sea water assimilation capacity. The suggested method provides for division of the sea waters into separated homogenous water masses. The aim of the study is to develop an inverse integrated synoptical method allowing synthesizing of such an optimum order for loading separate water masses with pollutants upon, at which the calculated total value of assimilation capacity would reach its maximum. The article shows the possibility of utilization of known synoptical method for determining assimilation capacity of sea waters in the inverse order, i.e. for calculating the maximum value of pollutant put into the fixed zone of sea waters, upon a condition of reaching the given amount of assimilation capacity and absence of essential negative effect on ecosystem. The task of calculating an optimum regime function of discrete type, upon which the integrated value of assimilation capacity would reach the maximum value, has been formulated. The solution of analogue equivalent of the formed optimization task is carried out using the Euler equation for a non-conditional variation optimization task, taking into account the accepted limitation condition. The recommendations on optimum loading of different sea water zones with determined type of pollutant have been given.

scholarly journals The Assessment Of Geographical Borders In Economic Research

2017 ◽  
Vol 19 (5) ◽  
pp. 99-123
Author(s):  
Małgorzata Markowska ◽  
Marek Sobolewski
Keyword(s):  
Spatial Analysis ◽  
Human Development Index ◽  
Moving Average ◽  
Economic Research ◽  
Simple Method ◽  
New Methods ◽  
Hierarchical Relations ◽  
Socio Economic Impact ◽  
Spatial Moving Average ◽  
The Given

The length of common border between two geographical units is frequently used as a basic weight in spatial analysis. The newest methodological propositions such as tests for hierarchical relations (Markowska et. al. 2014; Sokołowski et. al. 2013), regional spatial moving average and new spatial correlation coefficient (Markowska et. al. 2015) are using border lengths. In cited references new methods have been illustrated by analyses for EU NUTS2 regions. It is obvious that borders between regions belonging to different countries have different socio-economic impact than borders between regions lying in the same country. A new simple method for assesment the importance of borders is proposed in the paper. It is based on a chosen macroeconomic variable available at NUTS 2 level (e.g. GDP, infant mortality, Human Development Index). For neighboring regions bigger value is divided by smaller value giving the local importance of the given border. These measures of local border importance can be than average for borders within the same country and for borders for each pair of neighboring countries.

scholarly journals New Ranking Method For Fuzzy Numbers By Their Expansion Center

2014 ◽  
Vol 4 (3) ◽  
pp. 181-187 ◽  
Author(s):  
Zhenyuan Wang ◽  
Li Zhang-Westmant
Keyword(s):  
Decision Making ◽  
Data Analysis ◽  
Real Axis ◽  
Fuzzy Number ◽  
Fuzzy Numbers ◽  
Ranking Method ◽  
Important Criterion ◽  
Real Numbers ◽  
Numerical Index ◽  
The Membership Function

Abstract Based on the area between the curve of the membership function of a fuzzy number and the horizontal real axis, a characteristic as a new numerical index, called the expansion center, for fuzzy numbers is proposed. An intuitive and reasonable ranking method for fuzzy numbers based on this characteristic is also established. The new ranking method is applicable for decision making and data analysis in fuzz environments. An important criterion of the goodness for ranking fuzzy numbers, the geometric intuitivity, is also introduced. It guarantees coinciding with the natural ordering of the real numbers.

Edge (m,k)-choosability of graphs

2021 ◽  
Author(s):  
P. Soorya ◽  
K. A. Germina
Keyword(s):  
Connected Graph ◽  
Matching Number ◽  
Graph Theoretic ◽  
Maximum Value ◽  
Choice Number ◽  
The Given ◽  
Simple Connected Graph

Let [Formula: see text] be a simple, connected graph of order [Formula: see text] and size [Formula: see text] Then, [Formula: see text] is said to be edge [Formula: see text]-choosable, if there exists a collection of subsets of the edge set, [Formula: see text] of cardinality [Formula: see text] such that [Formula: see text] whenever [Formula: see text] and [Formula: see text] are incident. This paper initiates a study on edge [Formula: see text]-choosability of certain fundamental classes of graphs and determines the maximum value of [Formula: see text] for which the given graph [Formula: see text] is edge [Formula: see text]-choosable. Also, in this paper, the relation between edge choice number and other graph theoretic parameters is discussed and we have given a conjecture on the relation between edge choice number and matching number of a graph.

scholarly journals Measuring Loss-Based Process Capability IndexLeand Its GenerationLe′′with Fuzzy Numbers

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Mohammad Abdolshah
Keyword(s):  
Fuzzy Logic ◽  
Fuzzy Numbers ◽  
Process Capability ◽  
Process Capability Index ◽  
Process Capability Indices ◽  
Capability Index ◽  
Fuzzy Process ◽  
Capability Indices ◽  
Fuzzy Process Capability ◽  
The Membership Function

Loss-based process capability indices are appropriate and realistic tools in order to measure the process capability. Among them, indexLeand its generationLe′′are well-known loss-based process capability indices, whose concepts are based on the worth (the opposite concept of loss). Sometimes, in order to calculateLeandLe′′there are some uncertainties in observations, so fuzzy logic can be employed to manage the uncertainties. This paper investigates fuzzification of process capability indexL~eand its generationL~e′′. In order to find the membership function of process capability indicesL~eandL~e′′, theα-cuts of fuzzy observation were employed. Then with an example of fuzzy process capability index,L~eandL~e′′were calculated and compared. Results showed that fuzzyL~e′′was more sensitive compared withL~eand was increased while the target departs (asymmetric tolerance). This example also showed that, with departure from the target, variation of fuzzyL~e′′and consequently its fuzziness were increased.

Fuzzy Reliability of an Imprecise Failure to Start of an Automobile Using Pseudo-Parabolic Fuzzy Numbers

2018 ◽  
Vol 14 (03) ◽  
pp. 323-341 ◽  
Author(s):  
F. Abbasi
Keyword(s):  
Fuzzy Systems ◽  
Fuzzy Numbers ◽  
Extension Principle ◽  
Fuzzy Arithmetic ◽  
Fuzzy Reliability ◽  
Fuzzy Environment ◽  
Distributed Components ◽  
Proposed Model ◽  
New Type ◽  
The Membership Function

In this paper, we propose the notion of pseudo-parabolic fuzzy numbers and the component failure probabilities are considered as a new type of fuzzy number as pseudo-parabolic to incorporate the uncertainties in the parameter, due to a more realistic estimate of them. Then, we analyze the reliability of fuzzy system (particularly, series and parallel system) with independent and non-identically distributed components, and using the new operations of TA [F. Abbasi et al., Journal of Intelligent and Fuzzy Systems 29 (2015) 851–861], due to the smaller results support, easier calculations and special properties than fuzzy arithmetic operations based on the extension principle (in the domain of the membership function) and the interval arithmetic (in the domain of the [Formula: see text]-cuts). We provide a more realistic fuzzy reliability analysis. Finally, an imprecise failure to start of an automobile is considered in fuzzy environment. The reliability of components of the proposed model is considered as pseudo-parabolic fuzzy numbers.

Research on Fuzzy Fault Diagnosis of the Equipments

2013 ◽  
Vol 411-414 ◽  
pp. 1484-1487
Author(s):  
Ji Yang Qi ◽  
Li Na Ren ◽  
Shan Ping Ning ◽  
Yu Fu
Keyword(s):  
Fault Diagnosis ◽  
Set Theory ◽  
Fuzzy Set Theory ◽  
Fuzzy Numbers ◽  
Triangular Fuzzy Numbers ◽  
Comparison Matrix ◽  
Fuzzy Diagnosis ◽  
The Given ◽  
Pair Wise Comparison ◽  
Pair Wise Comparison Matrix

The paper introduces a method of fault diagnosis using fuzzy set theory. In the paper, the principle that a fault symptom either exists or doesnt exist is abandoned. A crisp number between 0 and 1 is used to denote the degree of fault symptom, by which the fault symptom vector is constructed. For every kind of fault symptom, a fuzzy pair-wise comparison matrix is constructed. The elements of the pair-wise comparison matrix are triangular fuzzy numbers which denote the qualitative comparisons between the membership values of the given fault symptom with the reference to a pair of possible faults respectively. The least logarithm squares method is applied to determine the membership of the fault symptom with respect to each fault, and then the fuzzy diagnosis matrix is constructed. A simple weighted addition is used to calculate the fault vector based on the fuzzy diagnosis matrix and the fault symptom vector. Center of area is used to determine the best non-fuzzy performance value of the fuzzy number, according to which the fuzzy numbers can be ranked. The ordering of all the possible faults based on the fault symptoms is determined. At the end of the paper, an example is used to demonstrate the procedure of fuzzy fault diagnosis.

Mountain Mapping Relaying Communication Positioning Algorithm

2013 ◽  
Vol 336-338 ◽  
pp. 1804-1808
Author(s):  
Sheng Jie Zhu ◽  
Xin Huan Feng
Keyword(s):  
Coverage Rate ◽  
Base Stations ◽  
Mountain Areas ◽  
New Methods ◽  
Mountain Terrain ◽  
Positioning Algorithm ◽  
The Given

Naturally, for the mountain mapping, the communication system's power is limited, As a matter of fact, the stations should be built as high as possible in order to eliminate the terrain shielding and radiate to the farther areas, however the number of users or other aspects also counts, In this paper, we introduced new methods to locate the modified location for the base stations in the mountain areas, and with this method, we use less stations to cover the most areas in the given situation. For a random mountain terrain. the coverage rate of this model is as high as 95.1%.

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