Abstract
The q-rung orthopair fuzzy numbers (q-ROFNs) are used to deal with vague and uncertain information and they are superior to the intuitionistic fuzzy numbers (IFNs) and the Pythagorean fuzzy numbers (PFNs). In this paper, we introduce two operators namely q-rung orthopair fuzzy hybrid weighted arithmetic geometric aggregation (q-ROFHWAGA) operator and q-rung orthopair fuzzy hybrid ordered weighted arithmetic geometric aggregation (q-ROFHOWAGA) operator. The suggested operators q-ROFHWAGA and q-ROFHOWAGA are superior to the existing operators defined on q-ROFNs. We present an application of the proposed operator of q-ROFHWAGA to multiple-attribute decision-making (MADM) in computer numerical control (CNC) machine. Furthermore, we present TOPSIS method based on q-ROFNs for MADM in transport policy problem.
Keywords
Introduction
For many years, the issue of vague and imperfect information has been at the forefront. Information aggregation is the key factor for the decision management in the areas of business, management, engineering, psychology, social sciences, medical sciences, and artificial intelligence. Traditionally, the information about an alternative has been believed to be a crisp number or linguistic number. Nevertheless, information can not be aggregated in a simple form due to its uncertainty. MADM is a critical framework for decision making science, the purpose of which is to identify the most exceptional goals among the most feasible ones. The person needs to assess the choices made by different types of assessment criteria, such as crisp numbers and intervals, in the actual decision-making process. However, in many cases, due to the presence of a number of data anomalies that may arise due to lack of knowledge or human error, it is difficult for a person to choose the correct choice. Consequently, in order to measure these inconsistencies and to analyze the mechanism, a large number of theories have been suggested. Zadeh [55] initiated the idea of fuzzy set with the help of membership function. Subsequently, the intuitionistic fuzzy set (IFS) was proposed by Atanassov [5] as an extension of the fuzzy set by means of the membership and the non-membership functions. Yager [47–49] introduced Pythagorean fuzzy set (PFS) as an extension of Atanassov’s IFS. Fuzzy sets, extensions of fuzzy sets, rough sets and soft sets with real life applications have been studied by many researchers; Akram [1, 2], Ali [3, 4], Chi and Lui [6], Feng et al. [7–9], Garg and Arora [10, 11], Hashmi et al. [13], Hashmi and Riaz [14], Jose and Kuriaskose [15], Kaur and Garg [16], Kumar and Garg [17], Karaaslan [18], Liu et al. [20], Naeem et al. [21–23], Peng and Yang [24], Peng and Yuan [25], Peng et al. [26], Peng and Selvachandran [27], Peng and Liu [28],Yu et al. [54], Riaz et al. [29–33], Riaz and Hashmi [34–36], Riaz and Tehrim [37–39], Shabir and Naz [40] and Tehrim and Riaz [42].
Xu [43–45] initiated IF and hesitant fuzzy aggregation operators. Ye [51, 52] introduced some operators of hesitant fuzzy set. Zhan et al. [56, 57] presented the concepts of rough soft hemirings, soft rough covering. Zhang et al. [58–61] established fuzzy soft β-covering based fuzzy rough sets and fuzzy soft coverings based fuzzy rough sets. Some hybrid weighted aggregation operators have been studied by Garg and Nancy [12], Shi and Yuan [41] and Ye [53].
In 2017, Yager introduced the idea of q-ROFS as the extension of PFS [50], in which the sum of membership degree
The researchers have developed many techniques to solve complex MADM problems based on q-ROF information. How to aggregate q-ROF information is a very important research topic for the researchers. If we use maximum and minimum operations to aggregate q-ROF information then only one value participate in final answer. So, we use different aggregation operator to aggregate the information and get comprehensive answer depending upon all values.
Liu and Wang [19], purposed q-rung orthopair fuzzy weighted averaging operator (q-ROFWA) and q-rung orthopair fuzzy weighted geometric operator (q-ROFWG). The q-ROFWG and q-ROFWA operators are two regular aggregation operators in the field of data fusion and decision-making within q-ROFN aggregation. In some cases, however, q-ROFWA and q-ROFWG operators have some deficiencies. For example, the aggregated result of the q-ROFWA and q-ROFWG operators tends towards to the maximum value or maximum weight value. In order to address the down sides of q-ROFWA and q-ROFWG operators in the aggregation of q-ROFNs, this paper introduced q-ROFHWAGA and q-ROFHOWAGA for more effective aggregation.
The remaining article is structured in the following manner. In Section 2, basic concepts related to q-ROFS are given. In Section 3, novel concept of q-ROFHWAGA and q-ROFHOWAGA operators is presented. In Section 4, MADM approach relating to proposed operators is presented and numerical example is given as well. In section 5 TOPSIS method based on q-ROFNs for MADM in transport policy problem is presented. Section 6 summarizes the results of this analytical research.
Preliminaries
We present description relating to the q-ROFS set in this section.
A basic element of the form
Operational laws of q-ROFSs
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
Operational laws of q-ROFNs
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(1)
(2)
(3)
(4)
(5)
(6)
For
(1) If
(2) If
If
If
Some basic aggregation operators on q-ROFNs
where T
n
is the set of all q-ROFNs, and
On the basis of operational laws of q-ROFNs we can calculate q-ROFWA as given by the following theorem.
(2.1) In the next example we explain the above idea.
where T
n
is the set of all q-ROFNs, and
Some drawbacks of q-ROFWA and q-ROFWG operators
As we know, in many MADM issues, q-ROFWA and q-ROFWG operators are being used to consolidate the data. However, their consolidated values can suggest certain irrational outcomes when those values converge toward the maximum arguments or weights. Here, we consider two cases and take q = 3 and σ = 0.5.
bfCase 1: Take two q-ROFNs such that
Some hybrid aggregation operators of q-ROFNs
In this section,we propose a new hybrid aggregation operator to overcome the shortcoming of the q-ROFWA and q-ROFGA operators.
q-ROFHWAGA operator
Assume that
According to properties of the q-ROFWA and q-ROFWG operators, it is clear that the q-ROFHWAGA operator also have properties of idempotency, boundedness and monotonicity.
q-ROFHOWAGA operator
Assume that
By score function we rank these q-ROFNs,
Numerical example
To show the appropriateness of the aggregated values of q-ROFHWAGA and q-ROFHOWAGA operators, we take first case of section 2.4. If we take σ = 0.5 and q = 3, we use the q-ROFHWAGA and q-ROFHOWAGA operators for the case.
For case 1, by (3), there is
In the above case, newly developed operators indicate the moderate values. it is obvious that these operators can overcome the shortcoming of q-ROFWA and q-ROFWG operators. Therefore the q-ROFHWAGA and q-ROFHOWAGA operators are more effective and reasonable in the information aggregation.
MADM with q-ROFHWAGA andq-ROFHOWAGA operators
Suppose that
bfAlgorithm 1
Case study
CNC stands for “Computer Numeric Control”. It is the result of the older term “NC”, which means “Numerical Control”. This refers to the idea of controlling machine tools through a computer. CNC machines are the same robot. With the term “NC” parents, computers need not be involved.. CNC machines are computer-controlled machine tools. Before CNC, machine tools were manually operated by machine experts. With CNC, computers control servos that serve machines. Essentially, they process robots. NC, and later CNC, allow for an incredible increase in capacity of machine tools, as they can be operated automatically without the constant attention of their operators.
CNC processing is a manufacturing process in which a computer runs a program that controls how the machine produces parts. CNC programs using these CNC software can control everything from machine movement to pivot speed, by starting or stopping the coolant and more. The computer language used for CNC programming machines is called G-Code. G-Code is a common term for the computer language industry that most CNC machines use to control their movements and the way they produce parts. CNC machines only understand the instructions provided by the G-code command. The list of CNC machines has been expanded. Here some other possibilities not mentioned:
(1) CNC Milling (2) CNC Lathes(3) CNC Routers(4) CNC Plasma Cutters, Lasers, and Water jets(5) CNC Electronic Discharge Machines (“EDM’s”)(6) CNC Foam Cutters(7) CNC Wire Bending and Tubing Bending (8) CNC Punches(9) CNC Embroidery (10) CNC Pattern Cutters (11) CNC Food Makers (12) CNC Pottery Printers Cutting tools are nothing new. From the first stone shaft to the modern final factory, mankind has invented and perfected tools since the earliest times. Most common materials you can use in CNC machine are:Carbon steelHigh-speed steel (HSS)Solid carbideCeramicsCubic boron nitrideDiamond Ceramics-alumina Cast cobalt alloys.
Application to selection of cutting tool ofCNC machine
Now we use Algorithm 1 to solve MADM problem of CNC machine. The procedural steps are elaborated as given below:
Comparison analysis
The proposed operator’s result is compared with two q-ROFWA and q-ROFWG operators, as indicated in the Table 2 as given below listing the results of the comparison in the final ranking of 4 alternatives. It can be observed in the comparison Table 2, the best selection made by the proposed operator is comparable with the already established operators which is expressive in itself and approves the reliability and validity of the proposed operator. The calculation of decision results based on various aggregation operator are given in Table 1 and pictorial view is in Figure 1.
Calculation of decision results based on various aggregation operator
Calculation of decision results based on various aggregation operator
Comparison analysis of final ranking

Graphical representation of calculation of decision results.
In this section, we explore how q-ROFS can be used in MADM using TOPSIS. First, we will extend TOPSIS to the q-ROFS and then consider an example of a method that has been proposed. Of the immense approaches found in the literature, TOPSIS has a central role to play in solving these problems. Depending on the nature of the problem, every technique has its own benefits and drawbacks.
Now we present q-ROFS TOPSIS method for MADM as given in Algorithm 2 below.
bfAlgorithm 2
q-ROFS TOPSIS method
where y
ij
is the weight assigned by the expert
where
Linguistic terms for judging alternatives
Linguistic terms for judging alternatives
where
where
and
where ∨ stands for q-ROFS union and ∧ represents q-ROFS intersection.
Flow chart of Algorithm 2 given in Figure 2.

Flow chart of q-ROF TOPSIS
Transport is essential need for daily routine life in this modern era. The modes of transport is buses, cars, train, bikes and lot of others. When public transport used, we have a lot of benefits like, reduces air pollution, increased fuel efficiency, increases mobility, saves money and it is safer. Here, we have a problem of a city transportation group which want to implement a transport system in the city. The available transport system are Car-share, Ride-share and Park and ride.
Car-share is the most popular in America. It is different from the traditional car rental. It is for those people who do not own the car and have used the car for several hours. People reserve their vehicle over the internet or call and get the vehicle at the required time and at the nearby destination. Another gain of car-share is that it allows you to access a car at any time, not just during business hours. Ride-sharing is a service which is used for one-way transportation on urgent basis. In ride sharing client booked their ride via mobile application or call at the end of ride client pay rent by bank account or in the form of cash. It is very common to go for college, universities and workplaces. One can see a ride near by on mobile application and booked this ride.
In park and ride car owner parked car near the bus station or railway station outside the city and connect with public transport. By park and ride people saved their time and money. The car is left in parking during the day and people get their cars when they returns.
Decision makers have different criterions to make a good decision, there are two types of criterions one is cost type and other one is benefit. Cost type criteria is suitable when its value is lower but benefit type criteria is suitable when its value is higher value.
Application of q-ROF TOPSIS
Criterions for transport system problem
Criterions for transport system problem
linguistic terms to each parameter by decision maker
From Table 5 we construct weighted parameter matrix
where w ij is the weight provided by the decision maker D i (row-wise) to each parameter C j (column-wise).
Normalize the matrix A
where
Distance measures & closeness coefficient of each alternative
Aggregation operators based on q-ROFNs namely q-ROFWA operators and q-ROFWG operators are important mathematical tool for aggregating q-rung orthopair fuzzy information. In order to overcome some drawbacks implied by the existing q-ROFWA operators and q-ROFWG operators in some real world problems, we developed two operators namely q-rung orthopair fuzzy hybrid weighted arithmetic geometric aggregation (q-ROFHWAGA) operator and q-rung orthopair fuzzy hybrid ordered weighted arithmetic geometric aggregation (q-ROFHOWAGA) operator. We established certain properties of q-ROFHWAGA and q-ROFHOWAGA operators. The suggested operators are superior to the existing operators defined on q-ROFNs and efficient to deal with vague and uncertain information. We elaborated the proposed operators with the help of illustrations. We presented MADM method for selecting the best material for cutting tool of CNC machine based on q-ROFHWAGA and q-ROFHOWAGA operators. Furthermore, we established q-ROF TOPSIS method to solve the transport policy problem. In the future, we will extend our work to solve other real world MADM problems by using different aggregation operators, TOPSIS, AHP, VIKOR, ELECTRE family and PROMETHEE family based on different hybrid structures of fuzzy sets like Pythagorean m-polar fuzzy sets, linear Diophantine fuzzy sets, cubic bipolar fuzzy sets and cubic m-polar fuzzy sets.
Acknowledgment
The authors would like to thank the Editor-in-Chief and the referees very much for their valuable input and Recommendations for making our paper more accurate.
