Jurnal Karya Asli Lorekan Ahli Matematik Vol. 7 No.2 (2015) Page 084-097 Jurnal Karya Asli Lorekan Ahli Matematik CONTINUOUS PARAMETER FREE FILLED FUNCTION METHOD Herlina Napitupulu1, Ismail Bin Mohd2 and Ridwan Pandiya3 1,2,3School of Informatics and Applied Mathematics, Universiti Malaysia Terengganu, Terengganu, Malaysia. [email protected], [email protected], [email protected] Abstract : In global minimization problems there are two difficulties faced by researchers, firstly is how to move from one local minimizer to another minimizer with less function value, secondly is how to decide that the current minima is the global. Filled function method is one of the recent known deterministic methods which widely studied by scientists to overcome these difficulties. This method has capability in solving multidimensional problems of multimodal function efficiently, and is considered as an easily applied method. Various kinds of parameter or parameter free filled functions, algorithm methods as well as its modifications are proposed for the sake of effectiveness and efficiency in solving global optimization problems. Unfortunately, until now there is no efficient technique that can be used to compute or to suggest any appropriate parameter. Moreover, many filled function methods need to choose more than one starting point if the involved functions have more than one global minimizer. In this paper, we propose a new filled function method without parameter that differs from any existing parameter free filled functions. Furthermore, we proposed an algorithm method for solving unconstrained global minimization problems by one starting point only. The performance of the algorithm has been supported by the numerical results presented in this paper, which show that our method is promising on solving global optimization problem. Keywords: Filled function, Newton’s method, steepest descent, global optimization. 1. Introduction Consider the unconstrained global minimization problem min f ( x) : n x n . (1.1) One of the most worthy of note research areas in mathematics especially in numerical analysis is to locating the global minimizer of a function of several variables. The reason is due to the existence of multiple local minimizers, which is different from the global minimizers. There are two main obstacles when we try to obtain the global one; how to jump from one to a lower local minimum point and how to give the decision that the current local minimizers is the global solution. Based on these two difficulties, almost all global optimization problems cannot be solved by classical nonlinear programming techniques directly. One of deterministic approach which handling the global optimization problems is known as filled function method, the method was initially proposed for smooth optimization by Ge [1]. The Ge’s filled function of f ( x) at isolated minimizer xk* over a domain D has the form P x, xk* , r , x x* k 1 exp 2 r f ( x) (1.2) where r and are adjustable parameters. Several filled functions have been proposed for reconsidering the obstacles of Ge’s filled function. Some of the proposed filled function are with parameter(s) (see [419], [22], [23] and others are without parameter (see [3], [20], [21]). However, those existing filled function methods are still have following limitations. (i). The existing filled functions do not give guarantee of the existence of a better local minimizer. © 2015 Jurnal Karya Asli Lorekan Ahli Matematik Published by Pustaka Aman Press Sdn. Bhd. Herlina Napitupulu et. al. (ii). Some filled functions in the literatures require the assumption that the objective function of global optimization problem has only a finite number of local minimizer. (iii). Many filled function methods give an assumption that every local minimizer has the different values, i.e. f ( x* ) f ( y* ) , if x* y* . Almost all filled function methods require parameter(s) to be adjusted. 2. One Dimensional Parameter Free Filled Function In [3], Goh et al. proposed a new class of filled function which does not require any parameter to be selected in finding the global minimizer. They used the idea of integration to build the filled function. Following is the form of parameter free filled function proposed in [3]. ds x xk* x * f ( s ) f xk xk* P x, xk* * xk * f ( s ) f xk x ds x xk* (2.1) where xk* is an isolated local minimum point of f ( x) . Under some conditions on the function f ( x) , the function P( x, xk* ) is a filled function of f ( x) and satisfy the definition of filled function ([3]). 3. Two Dimensional Parameter Free Filled Function In this paper, our proposed parameter free filled function is an approach to find the global minimizer of a multimodal function f ( x) on 2 , under the following assumptions : (i). f ( x) is a continuously differentiable function (ii). f ( x) has only a finite number of minimizers, and (iii). f ( x) as || x || The assumption (iii) implies the existence of a closed bounded domain D 2 such that D contains all minimizers of f ( x) and the value of f ( x) when x is on the boundary of D is greater than any values of f ( x) when x is inside D . Consider a function f : D D x , x T 1 2 2 where D is a box defined by | x1I x1 x1S x2 I x2 x2 S x1 x1I , x1S , x2 x2 I , x2 S (3.1) where x jI and x jS ( j 1, 2) are the infimum and supremum of the interval x j x jI , x jS respectively. Assume that x* ( x1* , x2* )T D is a current local minimizer of f . The domain D can be divided by x* 4 into four sub domains D1, D2 , D3 , and D4 such that D Di D1 D2 D3 D4 , where i 1 [ x2* , x2 S ] D2 x12 [ x1* , x1S ], x22 [ x2 I , x2* ] D3 x13 [ x1I , x1* ], x23 [ x2* , x2 S ] D4 x14 [ x1I , x1* ], x24 [ x2 I , x2* ] D1 x11 [ x1* , x1S ], x21 85 (3.2) Jurnal KALAM Vol. 7 No. 2, Page 084-097 Symbol xij denotes the interval of variable x j in sub domain Di (i 1, 2,3, 4) . Figure 3.1 shows the illustration of domain D with its sub domain Di (i 1, 2,3, 4) . ( x1* , x2* )T Figure 3.1 The subdomains D1 , D2 , D3 and D4 separated by ( x1* , x2* )T One extension of parameter free filled function [3] is so-called TIHR (Two dimensional Ismail Herlina Ridwan) function, Fi , defined on sub domain Di (i 1, 2,3, 4) , is given by * Fi x, x Fi1 x, x* f s1 , x2 f x1* , x2* ds1 , x1 x1i i x1 Fi 2 x, x* f x1 , s2 f x1* , x2* ds2 x2 x2i i x2 (3.3) The definition of TIHR function is given in Definition 3.1 and its validity is proved by Theorem 3.1Theorem 3.3 Definition 3.1 Fij ( x, x* ) ( i 1, 2; j 1, 2,3, 4 ) is called TIHR function of f ( x) at an isolated local minimizer x* in D 2 4 ( D Di ) if i 0 (i) x is a maximizer of Fij , Fij ( x* , x* ) Fij ( x, x* ) for all x D (ii) Fij has no stationary point in the set H1 x | f ( x) f ( x* ), x D (iii) There exist a point x H 2 x| f ( x) f ( x* ), W 0, xD \ x* such that x is a stationary point of * Fij where f s1 , x2 ds1 ( j 1) x2 i x1 W f x1 , s2 ds2 ( j 2) x1 x2i Theorem 3.1 If x* ( x1* , x2* )T 2 4 is an isolated minimizer of the objective function f x on D Di , i 0 * then x is a maximizer of filled function Fij ( i 1, 2; j 1, 2,3, 4 ). Proof. 86 Herlina Napitupulu et. al. Since f x1, x2 f x1* , x2* 0 for all sub domain Di (i 1, 2,3, 4) , we have f s1 , x2 f x1* , x2* ds1 0 for x1 x1i and i x1 f x1, s2 f x1* , x2* ds2 0 for x2 x2i i x2 Then for all x Di , Fij x, x* 0 ( i 1, 2; j 1, 2,3, 4 ). Therefore Fij x, x* 0 Fij x* , x* . ■ 4 Theorem 3.2 If ( x1* , x2* )T is a local minimizer of f ( x1, x2 ) on D Di and H1 x , x | f x , x f 1 2 1 2 i 1 x1* , x2* , x1, x2 D \ x1*, x2* , then FTIHR has no stationary point in the set H1 . Proof. Suppose that x1, x2 T H1 satisfies f x1, x2 f x1* , x2* . Consider FTIHR x, x* in sub domain D1 . Since f is a twice differentiable function, then F11 x1 ( f (x1, x2 ) f (x1*, x2* )) 0 and F11 x2 xx x2 f (s1, x2 ) f (x1*, x2* ) ds1 0 . 1 * 1 Therefore, F11 0 , means that F11 has no stationary point in H1 . For the gradient of F12 , also x f ( x1, s2 ) f ( x1* , x2* ) ds2 0 and F12 x2 ( f ( x1, x2 ) f ( x1* , x2* )) 0 . F12 x1 *2 x2 x 1 Thus F12 0 , means that F12 has no stationary point in H1 . Therefore, in sub domain D1 there is no stationary point of FTIHR in H1 . The similar proof can be applied to F2 , F3 and F4 ■ Theorem 3.3 If H 2 x1 , x2 T | f x1 , x2 f x1* , x*2 ,W ( x1 , x2 ) 0, x1 , x2 T D \ (x1* , x*2 )T where f s1 , x2 ds1 ( j 1) x2 i x1 W f x1 , s2 ds2 ( j 2) x1 x2i then there is a point x F ( x1F , x2F )T H 2 such that x F is a stationary point of Fij ( i 1, 2; j 1, 2,3, 4 ). Proof. Consider F11 in sub domain D1 . Suppose that for ( x1F , x2F )T H 2 , f x1F , x2F f x1* , x2* holds and satisfies x1 * x2 x1 f s1, x2 ds1 0 x xF Then F11 x, x * x x F T x1 f ( x1 , x2 ) f ( x1* , x2* ) , x* f ( s1 , x2 )ds1 x2 1 87 0, 0 T x xF Jurnal KALAM Vol. 7 No. 2, Page 084-097 Therefore, there exists a stationary point of F11 for ( x1, x2 )T H 2 . Next consider F12 in sub domain D1 . Also for ( x1F , x2F )T H 2 , f x1F , x2F f x1* , x2* holds and satisfies x2 0. * f x1 , s2 ds2 x1 x2 x xF Then F12 x, x* x x F T x2 * * x* f ( x1 , s2 )ds2 , f ( x1, x2 ) f ( x1 , x2 ) x1 2 0, 0 T x xF Therefore there exist a stationary point of F12 for ( x1, x2 ) H 2 . Similar proof can be applied to F2 , F3 and F4 ■ The Fij ( i 1, 2; j 1, 2,3, 4 ) in (3.3) has some special features which are described in this section. Consider the first equation of (3.3) written as Fi1 x, x* f s1 , x2 f x1* , x2* ds1 , x1 x1i i x1x1 The gradient of Fi1 is given by Fi1 x, x * T f s1 , x2 f x1 , x2 f x1* , x2* , ds1 x2 x1i There are two cases to be considered Case 1. f ( x) f ( x* ) . Clearly that, f x1 , x2 F Fi1 0 and i1 0 if 0 or x1 x2 x2 f x1 , x2 F F (b) i1 0 and i1 0 if 0 . x1 x x 2 2 (a) Case 2. f ( x) f ( x* ) . Clearly that, f x1 , x2 F Fi1 0 and i1 0 if 0 or x1 x x 2 2 f x1 , x2 F F (b) i1 0 and i1 0 if 0 . x1 x2 x2 (a) Furthermore, the matrix of second derivatives of Fi1 is given by 2 Fi1 x, x* f x 1 f x2 f x2 2 f s1 , x2 ds1 x22 x1i and its determinant is DFi1 Det 2 Fi1 x, x* f 2 f 2 f s1 , x2 ds 1 x2 x22 x1 x1i 88 (3.4) Herlina Napitupulu et. al. Now suppose that xFg is a stationary (critical) point of Fi1 . According to the second derivative test and (3.4) (a) xFg is a local minimum of Fi1 if DFi1 0 and f 0 x1 (b) xFg is a local maximum of Fi1 if DFi1 0 and f 0 x1 (c) xFg is a saddle point of Fi1 if DFi1 0 Furthermore, the gradient and the matrix of second derivative of Fi 2 (i 1, 2,3, 4) are given by Fi 2 x, x * f x1 , s2 ds2 , f x1 , x2 f x1* , x2* i x 1 x2 T and 2 Fi 2 x, x* 2 f x1 , s2 ds2 2 xi x 1 2 f x1 f x1 f x2 (3.5) Now suppose that xFg is a stationary point of Fi 2 and DFi 2 is the determinant of (3.5). Then (a) xFg is a local minimizer of Fi 2 if DFi 2 0 and 2 f x1 , s2 x12 x2i (b) xFg is a local maximizer of Fi 2 if DFi 2 0 and ds2 0 2 f x1 , s2 x12 x2i ds2 0 (c) xFg is a saddle point of Fi 2 if DFi 2 0 . By considering the first and second partial derivatives of Fij (i 1, 2,3, 4; j 1, 2) , the special features of Fij can be explored. Suppose that x* and x** are two nearest minimizer of f , and xFg is a stationary point of Fij x, x* (i 1, 2,3, 4; j 1, 2) lied between x* and x** . Consider these two cases. Case 1. f ( x** ) f ( x* ) . Clearly that a) g xF1 is a minimizer of Fij (of one dimensional) respect to x j -axis (see Figure 3.2), since 2 Fij x 2j x xFg1 f x j 0 when x xFg1 f x j 0 x xFg1 b) xFg2 is a maximizer of Fij (of one dimensional) respect to x j -axis (see Figure 3.2b), since 2 Fij x 2j x xFg2 f x j 0 when x xFg2 f x j 0. x xFg 2 We do not search the point xFg2 (maximizer of Fij with respect to x j -axis as explained in case 1 (b)) since this point is not the nearest zero of current minimizer x* . Consider only the point xFg1 (a 89 Jurnal KALAM Vol. 7 No. 2, Page 084-097 minimizer of Fij with respect to x j -axis as explained in case 1 (a)) which is attained while f decrease, in other words the next minimizer, x** , does not passed by yet. Figure 3.2 Illustration for special character of Fij Case 2. f ( x** ) f ( x* ) . Since 2 Fij x 2j x xF f x j 0. x xF for such a j then x F is an inflection point of Fij (of one dimensional) with respect to x j -axis (see Figure 3.3b). Figure 3.3 Illustration for special character of Fij 4. Algorithm Method and Numerical Experiment In this section we propose the algorithm method for solving global optimization problem using parameter free filled function, combine with radius of curvature, Newton’s method and steepest descent method. Following are the step of the algorithm. Data (initialization) specify initial point x0 , domain D , real number d > 0 and set, i 1 , j 1 , m 1 step 1 Specify initial step size of steepest descent 0 0, minimize f ( x) starting at x0 to obtain minimizer xm* step 2 Construct FTIHR function Fij ( x, xm* ) at xm* or x 1 f ( x) / x f ( x) / x step 3 Compute m* max x1 xm* , x2 xm* x1 2 3/2 1 2 * m 2 1 is too small, where x 1 f ( x) / x f ( x) / x * * : d if max x1 xm , x2 xm , x2 90 2 3/2 2 2 2 2 Herlina Napitupulu et. al. step 4 If i 4 then choose vector directions ei , where (e1 (1,1)T , e2 (1, 1)T , e3 (1,1)T , e4 (1, 1)T ) and go to step 5 else stop step 5 Set c : 1 step 6 Set initial point x0F xm* cm* ei . If x0F Di then go to step 7 else if j n then j : j 1 and go to step 5 else j 1; i : i 1; and go to step 4 step 7 If f ( x0F ) f ( xm* ) then set x0 : x0F , go to step 1 else if one of (i) or (ii) is true (i) (ii) F Fij x1 * * x xm c m ei * x xm (c 1) m* ei x2 ij 2 Fij x1 2 x2 ij F 2 * x xm cm* ei * x xm (c 1) m* ei 2 then go to step step 8 else c : c 1 and go to step 6 step 8 Solve Fij ( x, xm* ) 0 , (i 1, 2,., 4; j 1, 2) using Newton’s method with initial point x0F and obtain xF step 9 If (i) and (ii) hold then set x0 : x F , m : m 1 and go to step 1 else c : c 1 and go to step 6 (i) 2 Fij / x12 x x 0 or 2 Fij / x12 x x 104 for j 1 F F F 2 ij (ii) / x 2 2 x xF 0 or F 2 ij / x 2 2 x xF 104 for j 2 f ( x F ) f ( xm* ) 102 Some benchmark test functions are used for observing the capability of the Parameter Free Filled Function algorithm, the Visual C++ program are used for the algorithm. Problem 1. Six Hump Back Camel Function 1 f x1 , x2 4 x12 2.1x14 x16 x1 x2 4 x22 4 x24 ; D x1, x2 ([-5,5],[-5,5]) 3 There are 2 global minimum of this function i.e., x* (0.08984, 0.71265)T and x* (0.08984, 0.71265)T with function value f ( x* ) 1.03163 Problem 2. Three Hump Back Camel Function f x1 , x2 2 x12 1.05 x14 1 6 x1 x1 x2 x22 ; D x1, x2 ([-3,3],[-3,3]) 6 The global minimum of this function is x* (0,0)T with f ( x* ) 0 Problem 3. Shubert Function I 5 5 f x1 , x2 i cos (i 1) x1 i i cos (i 1) x2 i ; D x1, x2 ([-10,10],[-10,10]) i 1 i 1 This function has 760 minima. There are 18 global minimum with function value f ( x* ) 186.731 91 Jurnal KALAM Vol. 7 No. 2, Page 084-097 Problem 4. Shubert Function II 5 5 1 f x1 , x2 i cos (i 1) x1 i i cos (i 1) x2 i ( x1 +1.42513) 2 ( x2 0.80032) 2 i 1 i 1 2 D x1, x2 ([-10,10],[-10,10]) This function has 760 minima. The global minimum is x* (1.42513, 0.800321)T with function value f ( x* ) 186.731 Problem 5. Shubert Function III 5 5 f x1 , x2 i cos (i 1) x1 i i cos (i 1) x2 i ( x1 +1.42513) 2 ( x2 0.80032) 2 i 1 i 1 D x1, x2 ([10,10],[10,10]) This function has 760 minima. The global minimum is x* (1.42513, 0.800321)T with function value f ( x* ) 186.731 . The computational results are summarized in tables for each example. The symbol used in the tables are as follows. Symbols k , Fij , c , and d , denote number of iteration, evaluated Fij function in (3.3), an integer to be multiplied with , and positive real number which replaces if is too small, respectively. The symbols x0 , x F , and xk* represents an initial point for steepest descent method, a point which satisfies f ( x0 ) f ( xk* ) or a point for solution of F ( x, xk* ) 0 which satisfies f ( x F ) f ( xk* ) , and k-th minimizer obtained from steepest descent method respectively. The symbols f k* is the function value of xk* . All the global minimizer of each testing functions are written in bold. The numerical results given in Table 4.1-4.5, shows that the FTIHR algorithm method is succeed in solving two variable unconstrained global optimization problems of given functions. Table 4.1 Results for Six Hump Back Camel Function Results k 0 , Fij , c, 0 - x0 =(2,-1)T, f0 =5.73333 0 = 1.0 x1* =(1.6071,-0.568652)T, f1* = 2.10425 F31 , c =4, =0.132952 x0F =(1.0753,-0.036843)T, f 0F = 2.36695 0 = 0.01 x2* =(-0.0898424,-0.712657)T, f 2* = -1.03163 F11 , c =8, = 0.12825 x0F =(0.936161,0.313347)T, f 0F = 1.46949 0 = 0.01 x3* =(0.0898418,0.712656)T, f 3* = -1.03163 1 2 x F =( 0.909551,-0.166528)T, f F = 2.10424 x F =(0.0882539,0.707056)T, f F = -1.03137 k Table 4.2 Results for Three Hump Back Camel Function Results 0 , Fij , c, 0 - x0 =(-2,-1)T, f0 =0.866667 0 = 1.0 x1* =(-1.74755,-0.87378)T, f1* = 0.298638 F11 , c =3, =0.5 x0F =(-0.247552,0.62622)T, f 0F = 0.665833 1 x F =(-0.323583,-0.517783)T, f F = 0.298645 92 Herlina Napitupulu et. al. 0 = 0.25 x2* =((3.5559x10-7,1.83695x10-6)T, f 2* = 2.97408x10-12 Table 4.3 Results for Shubert I Function Results k 0 , Fij , c, 0 - x0 =(-1.5, 1.5)T, f0 =-14.1995 0 = 0.001 x1* =(-1.42513,1.32)T, f1* = -37.6811 F11 , c =2, =0.00106311, d=0.2 x0F =(-1.02513,1.72)T, f 0F = -15.2071 0 = 0.001 x2* =(-0.800321,1.80566)T, f 2* = -39.5887 F11 , c =15, =0.00106723, d=0.2 x0F =(2.19968,4.80566)T, f 0F = -29.5833 0 = 0.001 x3* =(0.334244,4.85806)T, f 3* = -49.5186 F11 , c =2, =0.000808974, d=0.2 x0F =(0.734244,5.25806)T, f 0F = -21.0711 0 = 0.001 x4* =(0.821784,5.48286)T, f 4* = -54.4049 F11 , c =10, =0.000776588, d=0.2 x0F =(2.82178,7.48286)T, f 0F = -5.26261 0 = 0.001 x5* =(5.48286,6.0878)T, f 5* = -123.577 F21 , c =3, =0.000341894, d=0.2 x0F =(6.08286,5.4878)T, f 0F = -123.495 0 = 0.001 x6* =(6.0878,5.48286)T, f 6* = -123.577 F31 , c =13, =0.000341894, d=0.2 x0F =(3.4878,8.08286)T, f 0F = -2.73236 0 = 0.001 x7* =(-7.08351,6.0878)T, f 7* = -123.577 F21 , c =3, =0.000341894, d=0.2 x0F =(-6.48351,5.4878)T, f 0F = -123.495 0 = 0.001 x8* =(-6.47857,5.48286)T, f8* = -123.577 F21 , c =20, =0.000341894, d=0.2 x0F =(-2.47857,1.48286)T, f 0F = -5.13392 0 = 0.001 x9* =(-0.195386,-0.800321)T, f 9* = -123.577 F11 , c =28, =0.000341894, d=0.2 x0F =(5.40461,4.79968)T, f 0F = -166.065 0 = 0.001 * * =(5.48286,4.85806)T, f10 = -186.731 x10 F31 , c =3, =0.000226263, d=0.2 x0F =(4.88286,5.45806)T, f 0F = -183.936 0 = 0.001 * * =(4.85806,5.48286)T, f11 = -186.731 x11 F21 , c =18, x0F =(8.45806,1.88286)T, f 0F = -4.99366 1 2 3 4 5 6 7 8 9 10 11 x F =(-0.864149,1.80566)T, f F = -37.6811 x F =(0.242784,4.85806)T, f F = -39.5887 x F =(0.817042,5.39569)T, f F = -49.5186 x F =(5.25519,6.0878)T, f F = -54.4049 x F =(6.08753,5.48286)T, f F = -123.577 x F =(-7.08309,6.0878)T, f F = -123.577 x F =(-6.47884,5.48286)T, f F = -123.577 x F =(-0.195634,-0.800474)T, f F = -123.577 x F =(5.40461,4.79968)T, f F = -166.065 x F =(4.85843,5.48286)T, f F = -186.731 93 Jurnal KALAM Vol. 7 No. 2, Page 084-097 12 13 14 15 16 17 18 19 20 21 22 23 =0.000226262, d=0.2 x F =(4.85799,-0.800545)T, f F = -186.731 0 = 0.001 * * =(4.85806,-0.800321)T, f12 = -186.731 x12 F21 , c =3, =0.000226262, d=0.2 x0F =(5.45806,-1.40032)T, f 0F = -183.936 0 = 0.001 * * =(5.48286,-1.42513)T, f13 = -186.731 x13 F31 , c =28, =0.000226262, d=0.2 x0F =(-0.117136,4.17487)T, f 0F = -39.6492 0 = 0.001 * * =(-0.800321,4.85806)T, f14 = -186.731 x14 F31 , c =3, =0.000226262, d=0.2 x0F =(-1.40032,5.45806)T, f 0F = -183.936 0 = 0.001 * * =(-1.42513,5.48286)T, f15 = -186.731 x15 F41 , c =15, =0.000226262, d=0.2 x0F =(-4.42513,2.48286)T, f 0F = -3.10727 0 = 0.001 * * =(-7.08351,-1.42513)T, f16 = -186.731 x16 F21 , c =25, =0.000226262, d=0.2 x0F =(-2.08351,-6.42513)T, f 0F = -45.2621 0 = 0.001 * * =(-1.42513,-7.08351)T, f17 = -186.731 x17 F21 , c =3, =0.000226262, d=0.2 x0F =(-0.825129,-7.68351)T, f 0F = -183.936 0 = 0.001 * * =(-0.800321,-7.70831)T, f18 = -186.731 x18 F31 , c =34, =0.000226262, d=0.2 x0F =(-7.60032,-0.908314)T, f 0F = -137.703 0 = 0.001 * * =(-7.70831,-0.800321)T, f19 = -186.731 x19 F11 , c =2, =0.000226262, d=0.2 x0F =(-7.30831,-0.400321)T, f 0F = -20.0319 0 = 0.001 * * =(-7.08351,4.85806)T, f 20 = -186.731 x20 F21 , c =25, =0.000226262, d=0.2 x0F =(-2.08351,-0.141943)T, f 0F = -45.2621 0 = 0.001 * * =(-1.42513,-0.800321)T, f 21 = -186.731 x21 F21 , c =3, =0.000226262, d=0.2 x0F =(-0.825129,-1.40032)T, f 0F = -183.936 0 = 0.001 * * =(-0.800321,-1.42513)T, f 22 = -186.731 x22 F21 , c =25, =0.000226262, d=0.2 x0F =(4.19968,-6.42513)T, f 0F = -45.2621 0 = 0.001 * * =(4.85806,-7.08351)T, f 23 = -186.731 x23 F21 , c =3, x0F =(5.45806,-7.68351)T, f 0F = -183.936 x F =(5.48247,-1.42513)T, f F = -186.731 x F =(-0.800031,4.85799)T, f F = -186.731 x F =(-1.42476,5.48286)T, f F = -186.731 x F =(-7.0832,-1.42513)T, f F = -186.731 x F =(-1.42549,-7.08351)T, f F = -186.731 x F =(-0.800718,-7.70831)T, f F = -186.731 x F =(-7.70795,-0.800321)T, f F = -186.731 x F =(-7.0839,4.85806)T, f F = -186.731 x F =(-1.42549,-0.800321)T, f F = -186.731 x F =(-0.800718,-1.42513)T, f F = -186.731 x F =(4.8577,-7.08351)T, f F = -186.731 94 Herlina Napitupulu et. al. 24 25 26 =0.000226262, d=0.2 x F =(5.48247,-7.70831)T, f F = -186.731 0 = 0.001 * * =(5.48286,-7.70831)T, f 24 = -186.731 x24 F31 , c =65, =0.000226262, d=0.2 x0F =(-7.51714,5.29169)T, f 0F = -61.7707 0 = 0.001 * * =(-7.70831,5.48286)T, f 25 = -186.731 x25 F21 , c =23, =0.000226262, d=0.2 x0F =(-3.10831,0.882864)T, f 0F = -10.1604 0 = 0.001 * * =(-7.08351,-7.70831)T, f 26 = -186.731 x26 F31 , c =3, =0.000226262, d=0.2 x0F =(-7.68351,-7.10831)T, f 0F = -183.936 0 = 0.001 * * =(-7.70831,-7.08351)T, f 27 = -186.731 x27 x F =(-7.70805,5.48286)T, f F = -186.731 x F =(-7.08383,-7.70831)T, f F = -186.731 x F =(-7.70794,-7.08351)T, f F = -186.731 Table 4.4 Results for Shubert II Function Results k 0 , Fij , c, 0 - x0 =(0.5,0.9)T, f0 =-2.49691 0 = 0.001 x1* =(0.331661, 0.818834)T, f1* = -11.5688 F11 , c =15, =0.00181691, d=0.2 x0F =(3.33166,3.81883)T, f 0F = 10.2742 0 = 0.001 x2* =(5.4805,6.08599)T, f 2* = -76.0079 F41 , c =2, =0.000341475, d=0.2 x0F =(5.0805,5.68599)T, f 0F = -2.01863 0 = 0.001 x3* =(-7.08223,-1.42499)T, f 3* = -170.531 F11 , c =23, =0.000226341, d=0.2 x0F =(-2.48223,3.17501)T, f 0F = -1.79234 0 = 0.001 x4* =(-1.42513,-0.800321)T, f 4* = -186.731 1 2 3 x F =(5.26512,6.132)T, f F = -11.5687 x F =(-7.07115,-1.64595)T, f F = -76.0079 x F =(-1.51032,-0.800321)T, f F = -170.531 Table 4.5 Results for Shubert III Function Results k 0 , Fij , c, 0 - x0 =(-1,1)T, f0 =-11.0314 0 = 0.001 x1* =(0.819615,-0.800321)T, f1* = -49.3611 F11 , c =29, =0.000775453, d=0.2 x0F =(6.61961,4.99968)T, f 0F = 61.1614 0 = 0.001 x2* =(4.85536,-0.800321)T, f 2* = -147.269 F42 , c =31, =0.000226181, d=0.2 x0F =(-1.34464,-7.00032)T, f 0F = -119.407 0 = 0.001 x3* =(-1.42513,-7.08066)T, f 3* = -147.27 F11 , c =47, =0.000226463, d=0.2 x0F =(7.97487,2.31934)T, f 0F = 92.2591 1 2 3 x F =(4.77877,-0.581157)T, f F = -49.3609 x F =(-1.42506,-7.07993)T, f F = -147.269 x F =(-0.831108,-1.29877)T, f F = -147.27 95 Jurnal KALAM Vol. 7 No. 2, Page 084-097 4 0 = 0.001 x4* =(-0.800604,-1.42486)T, f 4* = -185.95 F31 , c =3, =0.000226133, d=0.2 x0F =(-1.4006,-0.82486)T, f 0F = -183.996 0 = 0.001 x5* =(-1.42513,-0.800321)T, f 5* = -186.731 x F =(-1.40687,-0.800321)T, f F = -185.95 5. Conclusion From the numerical results in previous section, it is clear that TIHR algorithm which incorporate TIHR function, steepest descent method, radius of curvature and Newton’s method succeeds in solving unconstrained global optimization of given problems by using one starting point only. Summary of advantages of our proposed algorithm method are as follows: (i). (ii). (iii). (iv). (v). FTIHR has no parameter to be adjusted FTIHR continuous everywhere FTIHR has no exponential nor logarithmic term, FTIHR algorithm method has a simple stopping criteria FTIHR method succeeds in obtaining/exploring global minimizers of objective function which has more than one global minimizer with only one starting point. We conclude that our proposed method is a promising method that effective and efficient compared with another existing filled function method in solving global optimization problems. Acknowledgment This research was supported by Fundamental Research Grant Scheme of Malaysia Vot. 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