Optimization Algorithms of PERT/CPM Network Diagrams in Linear Diophantine Fuzzy Environment

The idea of linear Diophantine fuzzy set(LDFS)theory with its control parameters is a strong model for machine learning and optimization under uncertainty.The activity times in the critical path method(CPM)representation procedures approach are initially static,but in the Project Evaluation and Review Technique(PERT)approach,they are probabilistic.This study proposes a novel way of project review and assessment methodology for a project network in a linear Diophantine fuzzy(LDF)environment.The LDF expected task time,LDF variance,LDF critical path,and LDF total expected time for determining the project network are all computed using LDF numbers as the time of each activity in the project network.The primary premise of the LDF-PERT approach is to address ambiguities in project network activity timesmore simply than other approaches such as conventional PERT,Fuzzy PERT,and so on.The LDF-PERT is an efficient approach to analyzing symmetries in fuzzy control systems to seek an optimal decision.We also present a new approach for locating LDF-CPM in a project network with uncertain and erroneous activity timings.When the available resources and activity times are imprecise and unpredictable,this strategy can help decision-makers make better judgments in a project.A comparison analysis of the proposed technique with the existing techniques has also been discussed.The suggested techniques are demonstrated with two suitable numerical examples.

The Spherical q-Linear Diophantine Fuzzy Multiple-Criteria Group Decision-Making Based on Differential Measure

Spherical q-linearDiophantine fuzzy sets(Sq-LDFSs)provedmore effective for handling uncertainty and vagueness in multi-criteria decision-making(MADM).It does not only cover the data in two variable parameters but is also beneficial for three parametric data.By Pythagorean fuzzy sets,the difference is calculated only between two parameters(membership and non-membership).According to human thoughts,fuzzy data can be found in three parameters(membership uncertainty,and non-membership).So,to make a compromise decision,comparing Sq-LDFSs is essential.Existing measures of different fuzzy sets do,however,can have several flaws that can lead to counterintuitive results.For instance,they treat any increase or decrease in the membership degree as the same as the non-membership degree because the uncertainty does not change,even though each parameter has a different implication.In the Sq-LDFSs comparison,this research develops the differentialmeasure(DFM).Themain goal of the DFM is to cover the unfair arguments that come from treating different types of FSs opposing criteria equally.Due to their relative positions in the attribute space and the similarity of their membership and non-membership degrees,two Sq-LDFSs formthis preference connectionwhen the uncertainty remains same in both sets.According to the degree of superiority or inferiority,two Sq-LDFSs are shown as identical,equivalent,superior,or inferior over one another.The suggested DFM’s fundamental characteristics are provided.Based on the newly developed DFM,a unique approach tomultiple criterion group decision-making is offered.Our suggestedmethod verifies the novel way of calculating the expert weights for Sq-LDFSS as in PFSs.Our proposed technique in three parameters is applied to evaluate solid-state drives and choose the optimum photovoltaic cell in two applications by taking uncertainty parameter zero.The method’s applicability and validity shown by the findings are contrasted with those obtained using various other existing approaches.To assess its stability and usefulness,a sensitivity analysis is done.

关于Diophantine方程px+(p+2)~y=z^2的一个注记（英文）

设p是一个固定的奇素数.为了得到方程px+(p+2)y=z2的解,利用指数Diophantine方程和二次剩余的性质证明了当2y时,方程px+(p+2)y=z2无解(x,y,z);此外,如果p≡±3(mod 8)或p≠7,并且p+2是一个平方数,那么,方程也无解(x,y,z).

Spherical Linear Diophantine Fuzzy Sets with Modeling Uncertainties in MCDM

The existing concepts of picture fuzzy sets(PFS),spherical fuzzy sets(SFSs),T-spherical fuzzy sets(T-SFSs)and neutrosophic sets(NSs)have numerous applications in decision-making problems,but they have various strict limitations for their satisfaction,dissatisfaction,abstain or refusal grades.To relax these strict constraints,we introduce the concept of spherical linearDiophantine fuzzy sets(SLDFSs)with the inclusion of reference or control parameters.A SLDFSwith parameterizations process is very helpful formodeling uncertainties in themulti-criteria decisionmaking(MCDM)process.SLDFSs can classify a physical systemwith the help of reference parameters.We discuss various real-life applications of SLDFSs towards digital image processing,network systems,vote casting,electrical engineering,medication,and selection of optimal choice.We show some drawbacks of operations of picture fuzzy sets and their corresponding aggregation operators.Some new operations on picture fuzzy sets are also introduced.Some fundamental operations on SLDFSs and different types of score functions of spherical linear Diophantine fuzzy numbers(SLDFNs)are proposed.New aggregation operators named spherical linear Diophantine fuzzy weighted geometric aggregation(SLDFWGA)and spherical linear Diophantine fuzzy weighted average aggregation(SLDFWAA)operators are developed for a robust MCDM approach.An application of the proposed methodology with SLDF information is illustrated.The comparison analysis of the final ranking is also given to demonstrate the validity,feasibility,and efficiency of the proposed MCDM approach.

Diophantine方程组x-1=3pqa^2和x^2+x+1=3b^2

设p,q是适合3<p<q的奇素数,根据二次和四次Diophantine方程的结果,运用初等数论方法证明了:仅当(p,q)=(7,181)时方程组x-1=3pqa2和x2+x+1=3b2有正整数解(x,a,b)=(60 817,4,35 113).

关于Diophantine方程x^2+y^(2n)=z^3的可解性

运用有关三元Diophantine方程的新近结果,证明了一类Diophantine方程没有适合特定条件的正整数解,得到了更一般的结论,推广了相关文献的结果.

关于Diophantine方程x^3±1=pqy^2

关于Diophantine方程x3±1=Dy2至今仍未解决.论文利用同余式、平方剩余、Pell方程解的性质、递归序列证明:(1)p≡1(mod 12)为素数,q=12s2+1(s是正奇数)为素数,(p q)=-1时,Diophantine方程x3±1=pqy2仅有整数解(x,y)=(1,0);(2)p≡1(mod 24)为素数,q=12s2+1(s是正奇数)为素数,(p q)=-1时,Diophantine方程x3±1=pqy2仅有整数解(x,y)=(-1,0).

关于Diophantine方程x^3±1=3Dy^2

设D是奇素数,运用同余式、平方剩余、递归序列、Maple程序等初等方法得出了当D=27t2+1(t∈Z+)时,Diophantine方程x3±1=3 Dy2无正整数解的一个充分条件.

关于Diophantine方程(20n)~x+(21n)~y=(29n)~z(英文)

设a,b,c是满足条件a2+b2=c2的两两互素的正整数.Jesmanowicz于1956年猜想对于任意给定的正整数n,方程(an)x+(bn)y=(cn)z仅有解(x,y,z)=(2,2,2).本文证明了方程(20n)x+(21n)y=(29n)z有唯一解(x,y,z)=(2,2,2).

关于Diophantine方程x^3-1=13qy^2的整数解

设D=multiply from i=1 to s p_i(s≥2),p_i=1(mod 6)(1≤i≤s)为不同的奇素数.关于Diophantine方程x^3-1=Dy^2的初等解法至今仍未解决.主要利用同余式、平方剩余、Pell方程的解的性质、递归序列,证明了q≡7(mod 24)为奇素数.(q/13)=-1时,Diophantine方程x^3-1=13qy^2仅有整数解(x,y)=(1,0).

关于Diophantine方程(44n)^(x)+(117n)^(y)=(125n)^(z)的整数解

在Jesmanowícz猜想的基础上,利用初等方法证明了对任意的正整数n,Diophantine方程(44n)x+(117n)y=(125n)z仅有正整数解(x,y,z)=(2,2,2).

关于Diophantine方程x^3-5~3=3py^2

设p是给定的素数,运用初等数论方法证明了方程x3-53=3py2有适合gcd(x,y)=1的正整数解(x,y)的充要条件是p=Q(27a4+45a2+25),其中a是正整数,Q(27a4+45a2+25)是27a4+45a2+25的无平方因子部分.由此可知,当p≠7或13(mod30)时,该方程没有适合gcd(x,y)=1的正整数解(x,y).

关于三次Diophantine方程x^3+1=2p_1p_2Qy^2的可解性

设p_1,p_2是适合_p1≡p_2≡1(mod 6)以及(p_1/p_2)=-1的奇素数,其中(p_1/p_2)是Legendre符号。设Q是至少有两个不同素因数且每个素因数q都满足q≡5(mod 6)的无平方因子正整数。运用初等数论方法证明了:如果p_1≡1(mod 8),p_2≡5(mod 8),Q≡1(mod 4),那么方程x^3+1=2p_1p_2Qy^2无正整数解(x,y)。

关于指数Diophantine方程x^3-1=2py^2

设p是6k+1型的奇素数,运用Pell方程px2-3y2=1的最小解、同余式、平方剩余、勒让德符号的性质等初等方法证明了当p=3n(n+1)+1≡1,7(mod8)(n为单数)为奇素数,且2n+1为奇素数时,指数Diophantine方程x3-1=2py2无正整数解.

Diophantine方程p^x+q^y=z^2（英文）

设p和q是两个奇素数,且p<q.B.Sroysang证明了如果(p,q)=(7,19)或(7,31),则方程px+qy=z2没有正整数解(x,y,z).为了研究这个问题,运用初等方法和指数Diophantine方程的一些性质,证明了一个一般结果,即如果p+q≡2(mod4)和(q|p)=-1,则方程有唯一的正整数解(p,q,x,y,z)=(3,11,5,4,122),其中(q|p)表示Legendre符号.

关于指数Diophantine方程x^3+1=Dy^2

设D是6k+1型的奇素数,运用Pell方程px2-3y2=1的最小解、同余式、平方剩余等初等方法给出了:当D=12t2+1(t是奇数)时,Diophantine方程x3+1=Dy2无正整数解的一个充分条件.

Diophantine Quotients and Remainders with Applications to Fermat and Pythagorean Equations

Diophantine equations have always fascinated mathematicians about existence, finitude, and the calculation of possible solutions. Among these equations, one of them will be the object of our research. This is the Pythagoras’- Fermat’s equation defined as follows. (1) when , it is well known that this equation has an infinity of solutions but has none (non-trivial) when . We also know that the last result, named Fermat-Wiles theorem (or FLT) was obtained at great expense and its understanding remains out of reach even for a good fringe of professional mathematicians. The aim of this research is to set up new simple but effective tools in the treatment of Diophantine equations and that of Pythagoras-Fermat. The tools put forward in this research are the properties of the quotients and the Diophantine remainders which we define as follows. Let a non-trivial triplet () solution of Equation (1) such that . and are called the Diophantine quotients and remainders of solution . We compute the remainder and the quotient of b and c by a using the division algorithm. Hence, we have: and et with . We prove the following important results. if and only if and if and only if . Also, we deduce that or for any hypothetical solution . We illustrate these results by effectively computing the Diophantine quotients and remainders in the case of Pythagorean triplets using a Python program. In the end, we apply the previous properties to directly prove a partial result of FLT. .

关于Diophantine方程x^3±8=3Dy^2

利用初等数论的方法证明了:如果D是适合D≡5(mod8)的奇素数,则方程x3+8=3Dy2无正整数解;如果D是适合D≡7(mod8)的奇素数,则方程x3-8=3Dy2无正整数解。

关于Diophantine方程(a^n-1)(b^n-1)=x^2的Cohn猜想（英文）

设a和b是两个不相等的正整数.针对Cohn猜想,即方程(a^n-1)(b^n-1)=x2没有正整数解(x,n),其中n>4.利用初等数论方法和指数Diophantine方程的性质,得到了如果a和b具有相反的奇偶性,那么方程没有满足n>4和2|n的正整数解(x,n).

Diophantine方程(a^n-1)((a+1)~n-1)=x^2的可解性

设a是大于1的正整数,v2(a)表示2可以整除a的最高次幂.运用初等数论方法研究了方程(an-1)((a+1)n-1)=x2的可解性.证明了当a满足以下3个条件之一时该方程无解(x,n):(i)a是偶数,v2(a)是奇数;(ii)a是偶数,v2(a)=2;(iii)a是奇数且a≡5或9(mod 16).同时也证明了至少有5/6的正整数a可使该方程没有适合n>2的解(x,n).