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📋📋📋本文目录如下:🎁🎁🎁
目录
💥1 概述
📚2 运行结果
🎉3 参考文献
🌈4 Matlab代码实现
💥1 概述
灰狼优化(GWO)算法是基于灰狼社会等级及其狩猎与合作策略的新兴算法。该算法于2014年推出,已被大量研究人员和设计师使用,因此原始论文的引用次数超过了许多其他算法。在Niu等人最近的一项研究中,介绍了这种算法优化现实世界问题的主要缺点之一。总之,他们表明,随着问题的最佳解决方案从0发散,GWO的性能会下降。
在贪婪非分层灰狼优化器(G-NHGWO)中,通过对原始GWO算法进行直接修改,即忽略其社会等级,我们能够在很大程度上消除这一缺陷,并为该算法的未来使用开辟了新的视角。通过将所提方法应用于基准和实际工程问题,验证了该方法的效率。
文献来源:
📚2 运行结果
部分代码:
clc
clear
global NFE
NFE=0;
nPop=30; % Number of search agents (Population Number)
MaxIt=1000; % Maximum number of iterations
nVar=30; % Number of Optimization Variables
Total_Runs=25;
% Pre-allocating vectors and matrices
Cost_Rsult=nan(1,Total_Runs);
Rsult=nan(Total_Runs,MaxIt);
Mean=nan(1,14);
Best=Mean;
Std=Mean;
nfe=Mean;
fitness1=nan(1,nPop);
for nFun=1:14
NFE=0;
CostFunction=@(x,nFun) Cost(x,nFun); % Cost Function
for run_no=1:Total_Runs
%% Problem Definition
VarMin=-100; % Decision Variables Lower Bound
if nFun==7
VarMin=-600; % Decision Variables Lower Bound
end
if nFun==8
VarMin=-32; % Decision Variables Lower Bound
end
if nFun==9
VarMin=-5; % Decision Variables Lower Bound
end
if nFun==10
VarMin=-5; % Decision Variables Lower Bound
end
if nFun==11
VarMin=-0.5; % Decision Variables Lower Bound
end
if nFun==12
VarMin=-pi; % Decision Variables Lower Bound
end
if nFun==14
VarMin=-100; % Decision Variables Lower Bound
end
VarMax= -VarMin; % Decision Variables Upper Bound
if nFun==13
VarMin=-3; % Decision Variables Lower Bound
VarMax= 1; % Decision Variables Upper Bound
end
%% Grey Wold Optimizer (GWO)
% Initialize Best Solution (Alpha) which will be used for archiving
Alpha_pos=zeros(1,nVar);
Alpha_score=inf;
% Initialize the positions of search agents
Positions=rand(nPop,nVar).*(VarMax-VarMin)+VarMin;
Positions1=rand(nPop,nVar).*(VarMax-VarMin)+VarMin;
BestCosts=zeros(1,MaxIt);
fitness(1:nPop)=inf;
iter=0; % Loop counter
%% Main loop
while iter<MaxIt
for i=1:nPop
% Return back the search agents that go beyond the boundaries of the search space
Flag4ub=Positions1(i,:)>VarMax;
Flag4lb=Positions1(i,:)<VarMin;
Positions1(i,:)=(Positions1(i,:).*(~(Flag4ub+Flag4lb)))+VarMax.*Flag4ub+VarMin.*Flag4lb;
% Calculate objective function for each search agent
fitness1(i)= CostFunction(Positions1(i,:), nFun);
% Grey Wolves
if fitness1(i)<fitness(i)
Positions(i,:)=Positions1(i,:);
fitness(i) =fitness1(i) ;
end
% Update Best Solution (Alpha) for archiving
if fitness(i)<Alpha_score
Alpha_score=fitness(i);
Alpha_pos=Positions(i,:);
end
end
a=2-(iter*((2)/MaxIt)); % a decreases linearly fron 2 to 0
% Update the Position of all search agents
for i=1:nPop
for j=1:nVar
GGG=randperm(nPop-1,3);
ind1= GGG>=i;
GGG(ind1)=GGG(ind1)+1;
m1=GGG(1);
m2=GGG(2);
m3=GGG(3);
r1=rand;
r2=rand;
A1=2*a*r1-a;
C1=2*r2;
D_alpha=abs(C1*Positions(m1,j)-Positions(i,j));
X1=Positions(m1,j)-A1*D_alpha;
r1=rand;
r2=rand;
A2=2*a*r1-a;
C2=2*r2;
D_beta=abs(C2*Positions(m2,j)-Positions(i,j));
X2=Positions(m2,j)-A2*D_beta;
r1=rand;
r2=rand;
A3=2*a*r1-a;
C3=2*r2;
D_delta=abs(C3*Positions(m3,j)-Positions(i,j));
X3=Positions(m3,j)-A3*D_delta;
Positions1(i,j)=(X1+X2+X3)/3;
end
end
iter=iter+1;
BestCosts(iter)=Alpha_score;
fprintf('Func No= %-2.0f, Run No= %-2.0f, Iter= %g, Best Cost = %g\n',nFun,run_no,iter,Alpha_score);
end
🎉3 参考文献
部分理论来源于网络,如有侵权请联系删除。
Akbari, Ebrahim, et al. “A Greedy Non-Hierarchical Grey Wolf Optimizer for Real-World Optimization.” Electronics Letters, Institution of Engineering and Technology (IET), Apr. 2021, doi:10.1049/ell2.12176.