Friday, 24 June 2022

SOME APPLICATIONS OF VOLTERRA TYPE INTEGRO DIFFERENTIAL EQUATIONS

 SOME APPLICATIONS OF VOLTERRA TYPE INTEGRO DIFFERENTIAL EQUATIONS

Dr,K.R.Salini[1] , M. Deivanai[2], S.Madhavan[3] and Dr.S.Bamini[4]

[1] Guest Lecturer, PG & Department of Mathematics, Government Arts & Science College, Kariyampatti, Tirupattur, Tamilnadu, India.

Email: shalinimanoj1985@gmail.com

[2],[3] II M.Sc, Mathematics, PG & Department of Mathematics Government Arts & Science College, Kariyampatti, Tirupattur, Tamilnadu, India.

[4] Research Coordinator, Assistant Professor, PG & Research Department of Mathematics,

Marudhar Kesari Jain College for Women, Vaniyambadi, Tamilnadu, India.

Email: saransham07@gmail.com

Abstract

We determine the numerical solution of the specific nonlinear Voltera-Fredholm Integro-Differential Equation is proposed. The method is based on new vector forms for representation of triangular functions and its operational matrix.

Introduction

The nonlinear Volterra type integro-differential equation of the first order

y'(x)=f(x,y)+K(x. s. y(s))ds, y(x)= yox € [x.X]

Here the functions f(x,y). K(x.s, y) are determined in the domains

G=(x0 < x < x , |y| < αΆ―), G1=(x0 ≤ s ≤ x≤ X,|y| ≤ αΆ―)

and respectively and equation (1.1) has a unique solution.

In case K(x.s, y) ≡ 0 equation (1.1) turns into the Cauchy problem for ordinar

differential equations of the first order.

Non-Linear Volterra Type Integro Differentia Equation Applying Multi Step Method

The aim is to apply the multistep method with constant coefficients to the

solution of equation

Assume that the kernel K(x.s, y) is degenerate that is 𝐾(π‘₯,𝑠,𝑦)=Ξ£(π‘Žπ‘–(x)𝑏𝑖(s,y) )π‘šπ‘–=1

Then equation can be written as

y'(x) = f(x,y) + Ξ£π‘Žπ‘–(x)yπ‘šπ‘–=0∫𝑏𝑖(s,y(s))ds,yπ‘₯π‘₯0 y(x) = yo

Using the notation

Vi(x)=∫𝑏𝑖(s,y(s))π‘₯π‘₯0ds, (i=1.2,...m)

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We can rewrite equation in the form of a system of differential equations

y' = f(x,y)+ Ξ£(π‘Žπ‘–(x)𝑣𝑖(x))π‘šπ‘–=1

v'i(x)=bi (x,y(x)), ( i=1,2,....,m )

The initial conditions for the equation (1.3) of differential equations have the

following form

y(x0) = y0, vi(x0) = 0 ( i =1.2 ,……., m)

Consider the simple case and assume m = 1 then we have

y' ≡ f(x,y)+a(x)v(x),y(x 0 ) ≡ y0

v' (x) = b(x,y(x)),v(x0 ) = 0

Let's divide the section [x0 , X] by means of the constant step h > 0 into N equal parts

We apply k - th step method with constant coefficients to the numerical solution of

equation Then we can write

Ξ£π›Όπ‘˜π‘–=0i yn+i = hΞ£π›½π‘˜π‘–=0ifn+i + hΞ£π›½π‘˜π‘–=0ian+ivn+i (n=0,1,2,⋯ ⋯,𝑁−π‘˜)

Ξ£π›Όπ‘˜π‘–=0ivn+i = hΞ£π›½π‘˜π‘–=0ibn+i (n=0,1,2,⋯⋯,𝑁−π‘˜)

Where, am= a(xm)

vm = v(Xm)

bm = b(xm, ym)

fm = f(xm,ym)

xm = x0 + mh ( m = 0,1,2,..........)

If we assume that ak ≠ 0, then from equation (1.6) and equation (1.7) we can find yn+k and Vn+k respectively. However, relation (1.7) is the implicit nonlinear finite difference equation. Usually in these cases the different varients of prediction correction method is used

Non-Linear Volterra Type Integro Differential Equation Applying Prediction-Correction Method

Applying the prediction-correction method to equation (1.6) ,we have

ẏn+k = Ξ£(π›Όπ‘˜π‘–=0iyn+i + hΞ²ifn+i + hΞ²ian+i)

yn+k = Ξ£(π‘˜−1𝑖=0Ξ±'iyn+i + hΞ²'ifn+i + hΞ²'ian+ivn+i) + hΞ²' k f (f ( xn+k+yn+k) +an+kvn+k)

Where the coefficients of prediction are method are denoted Ξ±i, Ξ²j (l = 0,1,2, k-i) and by a="/a

Bi - B/a (i = 0,1,2....k-1).

Ξ²' k=Ξ²'k /Ξ±k, we denote the coefficients of the correction method.

Then the numerical method for solution of equation is obtained from methods

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vn+k = Ξ£Ξ±π‘˜−1𝑖=0'ivn+i + h Ξ£Ξ²π‘˜−1𝑖=0'ibn+i (n=0,1,2, ⋯⋯)

t is obvious that the found value ym vm (m ≥ k) by methods aren't the exact values of equation at the points xm (m ≥0).

Therefore, if in methods instead of the approximate values ym,vm we put their exact values y(xm), v(xm), these methods will take the following form

ẏ(xn+k) = Ξ£[π›Όπ‘˜−1𝑖=0iy(xn+i) + hΞ²if(xn+i,y(xn+i) + hΞ²ia(xn+i)v(xn+i)] +Řn

y(xn+k) = Ξ£[𝛼′π‘˜−1𝑖=0iy(xn+i) + hΞ²'if(xn+i,y(xn+i) + hΞ²'ia(xn+i)v(xn+i)] + hΞ²'kf(xn+k,y(xn+k) +

hΞ²'ka(xn+k)v(xn+i) + Rn

V(xn+k) = Ξ£Ξ±π‘˜−1𝑖=0'iv(xn+i) + h Ξ£Ξ²π‘˜π‘–=0'ib(xn+I,y(xn+i)) + Rn

Here the error of corresponding methods is denoted by Ř,Rn

Note that ẏ(xm) = y(xm) ( m = 0,1,2,⋯⋯)

Definition

Equation is stable if the roots of the polynomial

𝜌(πœ†) = Ξ£π›Όπ‘˜π‘–=0iπœ†i

lie inside a unique circle on whose boundary there are no multi roots.

Definition:

The integer-valued p is called of the degree of method (1.6),if the following

Ξ£[π›Όπ‘˜π‘–=0iy(x+i) - hΞ²iy'(x+ih)) = o(hp),h→0

holds

Determination of Convergence of The Proposed Method

Let us prove the following theorem for determination of convergence of the

proposed method.

Theorem

Let method (1.6) be stable, satisfy the conditions A, B, C. The first derivatives

of the function b (x, y) and f(x, y) by y be bounded. Then it holds

max0≤π‘š≤𝑁(β„°m,Êm) ≤ A exp (BX)(πœ‡max0≤π‘₯≤1| ℰ𝑖|+π‘šπ‘‘)

Here A, B and d are some bounded values and ΓŠπ‘š=𝑣(π‘₯π‘š)−π‘£π‘š,β„°π‘š=𝑦(π‘₯π‘š)−π‘¦π‘š(π‘š=0,1,2,⋯⋯,)

Proof:

ℰ𝑛+π‘˜=Ξ£(𝛼𝑖ℰ𝑛+𝑖+β„Žπ›½π‘–β„’π‘›+π‘˜β„‡π‘›+𝑖+β„Žπ›½π‘–π‘Žπ‘›+π‘–πœ€π‘›+𝑖 )+Ε˜π‘›π‘˜−1𝑖=0

ℰ𝑛+π‘˜=Ξ£(𝛼′𝑖ℰ𝑛+𝑖+β„Žπ›½π‘–β„’π‘›+π‘˜β„‡π‘›+𝑖+β„Žπ›½′π‘–π‘Žπ‘›+π‘–πœ€π‘›+𝑖 )+β„Žπ›½′π‘˜β„’π‘›+π‘˜β„‡π‘›+π‘˜+π‘˜−1𝑖=0

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β„Žπ›½′π‘˜π‘Žπ‘›+π‘˜β„‡π‘›+π‘˜+Ε˜π‘›

Here β„’π‘š=𝑓′𝑦(π‘₯π‘š,πœ‰π‘š),β„’π‘š=𝑓′𝑦(π‘₯π‘š,πœ‰π‘š),π‘Žπ‘š=π‘Ž(π‘₯π‘š),ΓŠπ‘š=𝑦(π‘₯π‘š)−αΊπ‘š

,( m = 0,1,2,.....)

Where πœ‰π‘š is found between y(xm) and ym and πœ‰π‘š between y(xm) and ẏm.

We have πœ€π‘›+π‘˜=Ξ£π‘Žπ‘–π‘’π‘›+𝑖+β„ŽΞ£π‘π‘–π‘’π‘›+𝑖+β„ŽΞ£π‘π‘–π‘˜−1𝑖=0πœ€π‘›+𝑖+β„Žπ›½′π‘˜π‘Žπ‘›+π‘˜πœ€π‘›+π‘˜+β„Žπ›½′π‘˜β„’π‘›+π‘˜Ε˜π‘›+β„›π‘›π‘˜−1𝑖=0π‘˜−1𝑖=0

Where, π‘Žπ‘–=𝛼′𝑖+β„Žπ›½′𝑖ℒ𝑛+𝑖𝛼𝑖, 𝑏𝑖=𝛽′𝑖ℒ𝑛+𝑖+β„Žπ›½′π‘˜β„’π‘›+π‘˜π›½π‘–β„’π‘›+1, 𝑐𝑖=𝛽′π‘–π‘Žπ‘›+𝑖+β„Žπ›½′𝑖ℒ𝑛+π‘˜π‘Žπ‘›+𝑖

we will obtain, πœ€π‘›+π‘˜=Ξ£(π‘Ž′𝑖𝑒𝑛+𝑖+β„Žπ›½′𝑖ℒ𝑛+π‘–π‘˜−1𝑖=0πœ€π‘›+𝑖)+β„Žπ›½′π‘˜β„’π‘›+π‘˜πœ€π‘›+π‘˜+ℛ𝑛

Where β„’π‘š=𝑏′𝑦(π‘₯π‘š,π‘¦π‘š) (m= 0,1,2,⋯⋯⋯,)πœ‚π‘š are between y(xm) and ym for error estimation of the method applied to the solution

We will obtain, πœ€π‘›+π‘˜=Ξ£π‘Žπ‘–πœ€π‘›+π‘–π‘˜−1𝑖=0+β„ŽΞ£π‘π‘–π‘˜−1𝑖=0πœ€π‘›+𝑖+ℛ𝑛

πœ€π‘›+π‘˜=Ξ£(π‘˜−1𝑖=0π‘Ž′π‘–πœ€π‘›+𝑖+β„Žπ›½′𝑖ℒ𝑛+π‘˜πœ€π‘›+𝑖+𝛽′π‘˜β„’π‘›+π‘˜Ξ£(π‘˜−1𝑖=0π‘Žπ‘–πœ€π‘›+𝑖+ β„Ž2π‘π‘–πœ€π‘›+𝑖)+β„Žπ›½′π‘˜β„’π‘›+π‘˜β„›π‘›+ℛ𝑛

Where, π‘Žπ‘–=π‘Žπ‘–+β„Žπ‘π‘–1−β„Ž2𝑑𝑛+π‘˜ 𝑏𝑖=𝑐𝑖+π‘Žπ‘›+π‘˜π›½′π‘˜π›Ό′𝑖1−β„Ž2𝑑𝑛+π‘˜ 𝑏𝑖=𝑏𝑖+β„Žπ‘Žπ‘›+π‘˜π›½′π‘˜π›½′𝑖ℒ𝑛+𝑖 𝑑𝑛+π‘˜=π‘Žπ‘›+π‘˜(𝛽′π‘˜)2ℒ𝑛+π‘˜

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ℛ𝑛=(β„Žπ›½′π‘˜β„’π‘›+π‘˜β„›π‘›+ℛ𝑛+β„Žπ‘Žπ‘›+𝑖ℛ𝑛)/1−β„Ž2𝑑𝑛+π‘˜

Consider the following relation

π‘Žπ‘–+β„Žπ‘π‘–/1−β„Ž2𝑑𝑛+π‘˜=π‘Žπ‘–+β„Žπ‘™π‘–

Where 𝑙𝑖=(𝑏𝑖+β„Žπ‘Žπ‘–π‘‘π‘›+π‘˜)/1−β„Ž2𝑑𝑛+π‘˜

For smallness of h we can assume |1−β„Ž2𝑑𝑛+π‘˜|≥12

Then we obtain that |𝑙𝑖|≤𝑙(i= 0,1,2, ⋯⋯-k-1)

It is easy to show that 𝑏𝑖=(𝑐𝑖+π‘Žπ‘›+π‘˜π›½′𝑖𝛼𝑖)/(1−β„Ž2𝑑𝑛+π‘˜) (𝑖= 0,1,2,⋯ ⋯,π‘˜−1)

are also bounded, that is,|𝑏𝑖| ≤ b.

we can write πœ€π‘›+π‘˜=Ξ£π‘Ž′π‘–πœ€π‘›+π‘–π‘˜−1𝑖=0+β„ŽΞ£π‘£π‘–π‘˜−1𝑖=0πœ€π‘›+𝑖+β„ŽΞ£π‘π‘–π‘˜−1𝑖=0πœ€π‘›+𝑖+ℛ𝑛

πœ€π‘›+π‘˜=Ξ£π‘Ž′π‘–πœ€π‘›+π‘–π‘˜−1𝑖=0+β„ŽΞ£π‘£π‘–π‘˜−1𝑖=0πœ€π‘›+𝑖+β„Ž2Σ𝑏𝑖𝛽′π‘˜β„’π‘›+π‘˜π‘˜−1𝑖=0πœ€π‘›+𝑖+Ε˜π‘›

Where, Ε˜π‘›=ℛ𝑛+β„Žπ›½′π‘˜β„’π‘›+π‘˜+ℛ𝑛 𝑣𝑖=𝛽′π‘˜β„’π‘›+π‘˜π›Όπ‘˜+𝑙𝑖 𝑣𝑖=𝛽′𝑖ℒ𝑛+𝑖+𝛼𝑖𝛽′π‘˜β„’π‘›+π‘˜ (𝑖=0,1,2,…,π‘˜−1)

Here we can also write that lvi| ≤v and |αΏ‘i|≤αΏ‘

Consider the following vectors,

Yn+k-1 (πœ€ n+k-1, πœ€ n+k-2, … … … , πœ€ n)

Ẏn+k-1 (πœ€ n+k-1, πœ€ n+k-2, … … … , πœ€ n)

Then adding to equation the following identities respectively,

π‘Œπ‘›+π‘˜=π΄π‘Œπ‘›+π‘˜−1+β„Žπ‘‰π‘›+π‘˜π‘Œπ‘›+π‘˜−1+β„Žπ΅π‘›+π‘˜αΊŽπ‘›+π‘˜−1+Ŵ𝑛,π‘˜

αΊŽπ‘›+π‘˜=π΄αΊŽπ‘›+π‘˜−1+β„ŽαΉΌπ‘›+π‘˜π‘Œπ‘›+π‘˜−1+β„Ž2𝐡𝑛+π‘˜αΊŽπ‘›+π‘˜−1+π‘Šπ‘›,π‘˜

Where the matrices A, Vn+kῑn+ki En+k. Ên+k and the vectors Wnk Ŵnk are

Determined in the following form 𝐴=(𝛼′π‘˜−1𝛼′π‘˜−2.10.00..𝛼′1𝛼′0 ....10) 𝑣𝑛+π‘˜=(π‘£π‘˜−1π‘£π‘˜−2.00.00..𝑣0...0)

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𝑩𝑛+π‘˜=(π΅π‘˜−1π΅π‘˜−2.00.00..𝑏0.0.0) 𝑩𝑛+π‘˜=(π‘π‘˜−1π‘π‘˜−2.00.00..𝑏0.000)(𝛽′π‘˜πΏπ‘›+π‘˜)−1 𝑣𝑛+π‘˜=(π‘£π‘˜−1π‘£π‘˜−2.00.00. .𝑣0 .0 .0) π‘Šπ‘›,π‘˜=(𝑅𝑛00) π‘Šπ‘›,π‘˜=(Ε˜π‘›00)

Using the vector Zn+k =(𝑦𝑛+π‘˜,αΊŽπ‘›+π‘˜)

We can rewrite equations in the following form 𝑍𝑛+π‘˜=𝐴𝑍𝑛+π‘˜−1β„Žπ‘‰π‘›+π‘˜π‘π‘›+π‘˜−1+Ŵ𝑛,π‘˜

Where, 𝐴=(𝐴00𝐴) 𝑉𝑛+π‘˜=(𝑉𝑛+π‘˜π΅π‘›+π‘˜π‘‰π‘›+π‘˜β„Žπ΅π‘›+π‘˜) Ŵ𝑛,π‘˜=(Ŵ𝑛,π‘˜Ε΄π‘›,π‘˜)

Note that Zn+k = Cyn+k

Then after the multiplication of equations (1.24) on the left hand side by C-1 we will obtain 𝑦𝑛+π‘˜=𝐷𝑦𝑛+π‘˜−1β„ŽπΈπ‘›+π‘˜π‘¦π‘›+π‘˜−1+Ŵ𝑛,π‘˜

determined in the following form 𝐷=𝐢−1Ậ𝐢 𝐸𝑛+π‘˜=𝐢−1Ṽ𝑛+π‘˜πΆ Ŵ𝑛,π‘˜=𝐢−1Ŵ𝑛,π‘˜

Passing to the norm in equation

we have, ‖𝑦𝑛+π‘˜‖≤‖𝐷‖‖𝑦𝑛+π‘˜‖+β„Ž‖𝐸𝑛+π‘˜‖‖𝑦𝑛+π‘˜−1‖+‖Ŵ𝑛,π‘˜‖

For the stability of equation (1.6) we can assert that the characteristic numbers of the matrix A satisfy the following condition: all characteristic numbers of the matrix by the modulus are less than unit, and the roots equal by the modulus of a unit are simple

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Since the matrix A is a Frobenius matrix smallness of h and 15,| bi |≤b,I = 0,1,2,...k-1 Then subject to the sufficient we will obtain that all characteristic numbers of the matrix A are situated in a unit circle on whose boundary that are no multi roots, to roots by the module equal to unit correspond the Jordan cells of dimension one.

Consequently,

||D||≤1

We can show that the matrices Vn+k. En+kiαΏ‘n+k have the bounded norms.

Then we can write

||En+k|| ≤ B

Subject to the above metrices Vn+k,En+k,αΏ‘n+k have the bounded norms

There we can write

||En+k||≤ B

Subject to the above mentioned in (1.26) we will obtain

||ym|| ≤ (1+hB)||ym-1||+d

Where.

d=||Ε΄n,k||

we will obtain that ‖π‘¦π‘š‖≤(1+β„Žπ΅)π‘š−π‘˜‖π‘¦π‘˜‖+Ξ£(1+β„Žπ΅)π‘–π‘š−π‘˜−1𝑖=0𝑑

It is known that (1+hB) m exp (mhB)

For h ≤ X-xo≤ X, We can rewrite in the following form ‖π‘¦π‘š‖≤exp(𝐡𝑋)(‖π‘¦π‘˜‖+π‘‘β„Ž−1) ‖𝑦𝑧‖≤𝐴exp(𝐡𝑋)(‖πœ‡‖‖π‘§π‘˜‖+π‘‘β„Ž−1)

Where, 𝐴=‖𝐢‖ πœ‡=‖𝐢−1‖

From the last it follows that maxπ‘˜≤π‘š≤𝑁(πœ€π‘š,πœ€π‘š)≤π‘Žexp(𝐡𝑋)(πœ‡max0≤𝑖≤π‘˜−1|πœ€π‘š|+𝑑𝑛)

If we assume that equation (1.6) is of degree p the initial values are calculated with

accuracy p.

That is,

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max0≤𝑖≤π‘˜−1πœ€π‘–=𝑂(β„Žπ‘)

Then from the assertions of the theorem it follows that πœ€π‘š=𝑂(β„Žπ‘),β„Ž→0

As we see from the proof of the theorem by using equation (1.7) it was assumed that

𝑦𝑛+π‘˜ is known. However, for finding 𝑦𝑛+π‘˜ is to be known 𝑣𝑛+π‘˜

Note that in real calculations for finding the values𝑣𝑛+π‘˜ - it is used approximate values of 𝑦𝑛+π‘˜ calculated by the prediction method.

In this case, the proposed method for the solution of equation (1.5) is written in the

following form αΊŽπ‘›+π‘˜=Ξ£(π‘Žπ‘–π‘¦π‘›+π‘–π‘˜π‘–=0+β„Žπ›½π‘–π‘“π‘›+𝑖+β„Žπ›½π‘–π‘Žπ‘›+𝑖,𝑣𝑛+𝑖) 𝑣𝑛+π‘˜=Ξ£π‘Ž′𝑖𝑣𝑛+π‘–π‘˜−1𝑖=0+β„ŽΞ£π›½′𝑖𝑏𝑛+𝑖+π‘˜−1𝑖=0β„Žπ›½′𝑖𝑏(π‘₯𝑛+π‘˜,αΊŽπ‘›+π‘˜) 𝑦𝑛+π‘˜=Ξ£π‘Ž′𝑖𝑦𝑛+π‘–π‘˜−1𝑖=0+β„ŽΞ£π›½′𝑖(𝑓𝑛+𝑖+π‘˜−1𝑖=0π‘Žπ‘›+𝑖𝑣𝑛+𝑖)+β„Žπ›½′π‘˜(π‘₯𝑛+π‘˜,αΊŽπ‘›+π‘˜)+π‘Žπ‘›+π‘˜π‘£π‘›+π‘˜

Reference

1. G.Yu.Mekhtieva, V.R.Ibrahimov “On one numerical method for solution of integro-differential equations”, Vestnik BSU, ser.phys.-math. Scien., 2003, No3, pp.21-27.(Russian).

2. H.Brunner, “Collection method for Volterra integral and Relation Functional Equations”, Cambridge University Press, Cambridge,2004.

3. P.Darania, E.Abadian, “A method for the numerical solution of the integro-differential equations”, Appl.Math. and Comput. 188(2007) 657-668.

4. B. Ahmad, S. Siva Sundaram, Existence Results For Nonlinear Impulsive Hybrid Boundary Value Problems involving Fractional Differential Equations, Non linear Analysis, hybrid System, 3(2009).

5. Z.B. Bai, H.S. Lii, Positive Solutions Of Boundary Valuve problems Of Nonlinear Fractional Differential Equations, J. Math Anal.Appl.311(2005)\

6. v. Lakshmikantham, D.D. Bainov And P.S. Simeonov, Theory Of Impulsive Differential Equations, modern Applied Mathematics (1989).

7. K.S. Miller, B.Ross, An Introduction To The Fractional Caculus And Fractional Differential Equations, Wiley, New York, 1993.

Wednesday, 11 May 2022

NUMERICAL SOLUTION OF NONLINEAR VOLTERRA-FREDHOLM INTEGRO-DIFFERENTIAL EQUATIONS VIA DIRECT METHOD USING TRIANGULAR FUNCTIONS

 Dr.K.R.Salini[1] and Dr.S.Bamini[2]

[1] Guest Lecturer, PG & Department of Mathematics, Government Arts & Science College, Kariyampatti, Tirupattur, Tamilnadu, India.

Email: shalinimanoj1985@gmail.com

[2] Research Coordinator, Assistant Professor, PG & Research Department of Mathematics, Marudhar Kesari Jain College For Women, Vaniyambadi, Tamilnadu, India.

Email: saransham07@gmail.com

Abstract

We determine the numerical solution of the specific nonlinear Voltera-Fredholm Integro-Differential Equation is proposed. The method is based on new vector forms for representation of triangular functions and its operational matrix.

Introduction

A set of basic functions and an appropriate projection method or a direct method. These methods often transform an integro-differential equation to a linear or nonlinear system of algebraic equations which can be solved by direct or iterative methods.

Consider a Volterra-Fredhlom Integro-differential equations of the form π‘₯′(𝑠)+π‘ž(𝑠)π‘₯(𝑠)+πœ†1∫π‘˜1(𝑠,𝑑)𝐹(π‘₯(𝑑))𝑑𝑑10+πœ†2∫π‘˜2(𝑠,𝑑)𝐺(π‘₯(𝑑))𝑑𝑑10=𝑦(𝑠)

π‘₯(0)=π‘₯0

Where the functions 𝐹(π‘₯(𝑑)) and 𝐺(π‘₯(𝑑)) are polynomials of π‘₯(𝑑) with constant coefficients.

For convenience, we put 𝐹(π‘₯(𝑑))=[π‘₯(𝑑)]𝑛1 and 𝐺(π‘₯(𝑑))=[π‘₯(𝑑)]𝑛2, where 𝑛1 & 𝑛2 are positive integers.

For 𝑛1,𝑛2=1, equation (1.1) is a linear integro- differential equation.

We present new vector forms of triangular functions (TFs), operational matrix of integration, expansion of functions of one and two variables with respect to TFs and other TFs properties.

By using new representations, a nonlinear integro-differential equation can be easily reduced to a nonlinear system of algebraic equations.

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Triangular Functions

Definition

Two π‘š-sets of triangular functions are defined over the intercal [0,𝑑) as 𝑇1𝑖(𝑑)={1−𝑑−π‘–β„Žβ„Žπ‘–β„Ž≤𝑑<(𝑖+1)β„Ž0π‘œπ‘‘β„Žπ‘’π‘Ÿπ‘€π‘–π‘ π‘’ 𝑇2𝑖(𝑑)={𝑑−π‘–β„Žβ„Žπ‘–β„Ž≤𝑑<(𝑖+1)β„Ž0π‘œπ‘‘β„Žπ‘’π‘Ÿπ‘€π‘–π‘ π‘’

Where 𝑖=0,1,2…π‘š−1 with a positive integer value for m.

Also consider β„Ž=𝑇/π‘š, and 𝑇1𝑖 as the π‘–π‘‘β„Ž left-handed triangular function and 𝑇2𝑖 as

the π‘–π‘‘β„Ž right-handed triangular function.

It is assumed that 𝑇=1, so TFs are defined over [0,1) and β„Ž=1/π‘š.

From the definition of TFs, it is clear that triangular functions are disjoint, orthogonal

and complete.

We can write ∫𝑇1𝑖10(𝑑)𝑇1𝑗(𝑑)𝑑𝑑=∫𝑇2𝑖10(𝑑)𝑇2𝑗(𝑑)𝑑𝑑={β„Ž3𝑖=𝑗0𝑖≠𝑗

Also, ∅𝑖(𝑑)=𝑇1𝑖(𝑑)+𝑇2𝑖,𝑖=0,1,…π‘š−1

Where ∅𝑖(𝑑) is the 𝑖th block-pulse function defined as ∅𝑖(𝑑)={1π‘–β„Ž≤𝑑<(𝑖+1)β„Ž0π‘œπ‘‘β„Žπ‘’π‘Ÿπ‘€π‘–π‘ π‘’

Where 𝑖=0,1,…π‘š−1.

Vector Forms

Consider the first π‘š terms of the left-handed triangular functions and the first π‘š terms of the right- handed triangular functions and write them concisely as π‘š-vectors. 𝑇1(𝑑)=[𝑇10(𝑑),𝑇11(𝑑),…𝑇1π‘š−1(𝑑)]𝑇

𝑇2(𝑑)=[𝑇20(𝑑),𝑇21(𝑑),…𝑇2π‘š−1(𝑑)]𝑇

Where 𝑇1(𝑑) and 𝑇2(𝑑) are called left-handed triangular functions (LHTF) and right-handed triangular functions (RHTF) vector, respectively.

The product of two TFs vectors are

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𝑇1(𝑑)𝑇1𝑇(𝑑)≅( 𝑇10(𝑑)0⋯⋯⋯00𝑇11(𝑑)⋯⋯⋯0⋮⋮0⋮⋮0⋮⋮⋯⋮⋮⋯⋮⋮⋯⋮⋮𝑇1π‘š−1(𝑑))

𝑇2(𝑑)𝑇2𝑇(𝑑)≅( 𝑇20(𝑑)0⋯⋯⋯00𝑇21(𝑑)⋯⋯⋯0⋮⋮0⋮⋮0⋮⋮⋯⋮⋮⋯⋮⋮⋯⋮⋮𝑇2π‘š−1(𝑑)) 𝑇1(𝑑)𝑇2𝑇(𝑑)=0

𝑇2(𝑑)𝑇1𝑇(𝑑)=0

Where 0 is the π‘§π‘’π‘Ÿπ‘œ π‘š×π‘š matrix.

Also ∫𝑇110(𝑑)𝑇1𝑇(𝑑)𝑑𝑑=∫𝑇2(𝑑)𝑇1𝑇(𝑑)𝑑𝑑10≅β„Ž3𝐼

∫𝑇110(𝑑)𝑇2𝑇(𝑑)𝑑𝑑=∫𝑇2(𝑑)𝑇1𝑇(𝑑)𝑑𝑑10≅β„Ž6𝐼

In which 𝐼 is an π‘š×π‘š identity matrix.

TFs Expansion

The expansion of a function 𝑓(𝑑) over [0,1) with respect to TFs written as 𝑓(𝑑)≅Ξ£π‘π‘–π‘š−1𝑖=0𝑇1𝑖(𝑑)+Ξ£π‘‘π‘–π‘š−1𝑖=0𝑇2𝑖(𝑑) 𝑓(𝑑)=𝑐𝑇𝑇1(𝑑)+𝑑𝑇𝑇2(𝑑)

Where we may put 𝑐𝑖=𝑓(π‘–β„Ž) and 𝑑𝑖=𝑓((𝑖+𝑖)β„Ž) for 𝑖=0,1,2,..π‘š−1.

Operational Matrix of Integration

Expressing ∫𝑇1(𝜏)π‘‘πœ≅𝑃1𝑇1(𝑠)+𝑃2𝑇2(𝑠)𝑠0

∫𝑇2(𝜏)π‘‘πœ≅𝑃1𝑇1(𝑠)+𝑃2𝑇2(𝑠)𝑠0

Where 𝑃1π‘š×π‘š and 𝑃2π‘š×π‘š are called operational matrices of integration in TFs domain and represented as follows 𝑃1=β„Ž2( 011⋯1001⋯10⋮00⋮00⋮0⋯⋱⋯1⋮0)

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𝑃2=β„Ž2( 111⋯1011⋯10⋮00⋮00⋮0⋯⋱⋯1⋮1)

So the integral of any function 𝑓(𝑑) can be approximated as ∫𝑓(𝜏)π‘‘πœ≅𝑐𝑇𝑇1(𝑠)+𝑑𝑇𝑇2(𝑠)π‘‘πœπ‘ 0 ∫𝑓(𝜏)π‘‘πœ≅(𝑐+𝑑)𝑇𝑃1𝑇1(𝑠)+(𝑐+𝑑)𝑇𝑃2𝑇2(𝑠)𝑠0

New Representation of TFs Vector Forms and Other Properties

We define a new representation of TFs vector forms. Then, some characteristics of TFs are presented using the new definition.

Definition and Expansion

Let 𝑇(𝑑) be a 2π‘š-vector defined as 𝑇(𝑑)=(𝑇1(𝑑)𝑇2(𝑑)),0<𝑑<1

Where 𝑇1(𝑑) and 𝑇2(𝑑) have been defined in (1.2).

Now, the expansion of 𝑓(𝑑) with respect to TFs can be written as 𝑓(𝑑)≅𝐹1𝑇𝑇1(𝑑)+𝐹2𝑇𝑇2(𝑑)

≅𝐹𝑇𝑇(𝑑)

Where 𝐹1 &𝐹2 are TFs co-efficients with

𝐹1𝑖=𝑓(π‘–β„Ž)& 𝐹2𝑖=𝑓((𝑖+1)β„Ž),

For 𝑖=0,1,…π‘š−1.

Also, 2π‘š-vector 𝐹 is defined as 𝐹=(𝐹1𝐹2)

Now, assume that π‘˜(𝑠,𝑑) is a function of two variables. It can be expanded with respect to TFs as follows

π‘˜(𝑠,𝑑)≅𝑇𝑇(𝑠)𝐾𝑇(𝑑)

Where 𝑇(𝑠)& 𝑇(𝑑) are 2π‘š1&2π‘š2 dimensional triangular functions and 𝐾 is a

2π‘š1×2π‘š2 TFs coefficient matrix.

For convenience, we put π‘š1=π‘š2=π‘š. So matrix 𝐾 can be written as

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𝐾=((𝐾11)π‘š×π‘š(𝐾12)π‘š×π‘š(𝐾21)π‘š×π‘š(𝐾22)π‘š×π‘š)

Where 𝐾11,𝐾12,𝐾21,𝐾22 can be compted by sampling the function π‘˜(𝑠,𝑑) at points 𝑠𝑖 & 𝑑𝑗 such that 𝑠𝑖=π‘–β„Ž & 𝑑𝑗=π‘—β„Ž, for 𝑖,𝑗=0,1,…π‘š. (𝐾11)𝑖𝑗=π‘˜(𝑠𝑖,𝑑𝑗),𝑖=0,1,…π‘š−1,𝑗=0,1,…π‘š−1 (𝐾12)𝑖𝑗=π‘˜(𝑠𝑖,𝑑𝑗),𝑖=0,1,…π‘š−1,𝑗=0,1,…π‘š (𝐾21)𝑖𝑗=π‘˜(𝑠𝑖,𝑑𝑗),𝑖=0,1,…π‘š,𝑗=0,1,…π‘š−1 (𝐾22)𝑖𝑗=π‘˜(𝑠𝑖,𝑑𝑗),𝑖=0,1,…π‘š,𝑗=0,1,…π‘š

Product Properties

Let 𝑋 be an 2π‘š-vertor which can be written as 𝑋𝑇=(𝑋1𝑇 𝑋2𝑇) such that 𝑋1 & 𝑋2 are π‘š-vectors.

It can be concluded from (1.3) & (1.4) that 𝑇(𝑑)𝑇𝑇(𝑑)𝑋=(𝑇1(𝑑)𝑇2(𝑑))(𝑇𝑇(𝑑)𝑇2𝑇(𝑑))(𝑋1𝑋2)

≅(𝑑𝑖𝑔(𝑇1(𝑑))π‘œπ‘š×π‘šπ‘œπ‘š×π‘šπ‘‘π‘–π‘”(𝑇2(𝑑)))(𝑋1𝑋2)

=𝑑𝑖𝑔 (𝑇(𝑑))𝑋

=𝑑𝑖𝑔(𝑋)𝑇(𝑑)

Therefore,

𝑇(𝑑)𝑇𝑇(𝑑)𝑋≅𝑋̅ 𝑇(𝑑)

Where 𝑋̅=𝑑𝑖𝑔(𝑋) is an 2π‘š×2π‘š diagonal matrix.

Let 𝐡 be a 2π‘š×2π‘š matrix as 𝐡=((𝐡11)π‘š×π‘š(𝐡12)π‘š×π‘š(𝐡21)π‘š×π‘š(𝐡22)π‘š×π‘š)

So, it can be similarly concluded from equations (1.3) and (1.4) that 𝑇(𝑑)𝐡𝑇(𝑑)=𝑇1𝑇(𝑑)𝑇2𝑇(𝑑)(𝐡11𝐡12𝐡21𝐡22)(𝑇1(𝑑)𝑇2(𝑑)) ≅𝑇1𝑇(𝑑)𝐡11𝑇1(𝑑)+𝑇2𝑇(𝑑)𝐡22𝑇2(𝑑) ≅𝐡̂11𝑇𝑇1(𝑑)+𝐡̂22𝑇𝑇2(𝑑)

Where 𝐡̂11 and 𝐡̂22 are π‘š−vectors with elements equal to the diagonal entries of matrices 𝐡11 and 𝐡22 respectively.

Therefore,

𝑇𝑇(𝑑)𝐡𝑇(𝑑)≅𝐡̂ 𝑇𝑇(𝑑)

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In which 𝐡̂ is a 2π‘š- vector with elements equal to the diagonal entries of matrix 𝐡.

It is immediately concluded from equation (1.5) that ∫𝑇10(𝑑)𝑇𝑇(𝑑)𝑑𝑑=∫(𝑇1(𝑑)𝑇2(𝑑))𝑇1𝑇(𝑑)𝑇2𝑇(𝑑)𝑑𝑑10

=∫(𝑇1(𝑑)𝑇1𝑇(𝑑)𝑇1(𝑑)𝑇2𝑇(𝑑)𝑇2(𝑑)𝑇1𝑇(𝑑)𝑇2(𝑑)𝑇2𝑇(𝑑))𝑑𝑑10

≅(β„Ž3πΌπ‘š×π‘šβ„Ž6πΌπ‘š×π‘šβ„Ž6πΌπ‘š×π‘šβ„Ž3πΌπ‘š×π‘š)

Therefore,

∫𝑇10(𝑑)𝑇𝑇(𝑑)𝑑𝑑≅𝐷

Where 𝐷 is the following 2π‘š×2π‘š matrix. 𝐷=β„Ž3( 10⋯012⁄0⋯001⋯0012⁄⋯0⋮012⁄0⋮0⋮0012⁄⋮0⋱⋯⋯⋯⋱⋯⋮100⋮12⁄⋮010⋮0⋮001⋮0⋱…⋯⋯⋱⋯⋮12⁄00⋮1)

Operational Matrix

Expressing ∫𝑇(𝜏)π‘‘πœπ‘ 0 in terms of 𝑇(𝑠), we can write ∫𝑇(𝜏)π‘‘πœπ‘ 0=∫(𝑇1(𝜏)𝑇2(𝜏))π‘‘πœπ‘ 0

≅(𝑃1𝑇1(𝑠)+𝑃2𝑇2(𝑠)𝑃1𝑇1(𝑠)+𝑃2𝑇2(𝑠))

=(𝑃1𝑃2𝑃1𝑃2)(𝑇1(𝑠)𝑇2(𝑠))

So, ∫𝑇(𝜏)π‘‘πœπ‘ 0≅𝑃𝑇(𝑠)

Where 𝑃2π‘š×2π‘š, operational matrix of 𝑇(𝑠) is

𝑃=(𝑃1𝑃2𝑃1𝑃2) (

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Where 𝑃1 & 𝑃2 are given by

The integral of any function 𝑓(𝑑) can be approximated as ∫𝑓(𝜏)π‘‘πœπ‘ 0≅∫𝐹𝑇𝑇(𝜏)π‘‘πœπ‘ 0

≅𝐹𝑇𝑃𝑇(𝑠)

Solving Nonlinear Integro-Differential Equation

Consider the following nonlinear Volterra-Fredhlom integro-differential equation

{π‘₯′(𝑠)+π‘ž(𝑠)π‘₯(𝑠)+πœ†1∫π‘˜1(𝑠,𝑑)[π‘₯(𝑑)]𝑛1𝑑𝑑+𝑠0πœ†2∫π‘˜2(𝑠,𝑑)[π‘₯(𝑑)]𝑛2𝑑𝑑=𝑦(𝑠)𝑠0π‘₯(0)=π‘₯0, 0≤𝑠<1,𝑛1,𝑛2≥1

Where the parameters πœ†1 and πœ†2 and β„’2 functions π‘ž(𝑠),𝑦(𝑠),π‘˜1(𝑠,𝑑),π‘˜2(𝑠,𝑑) are known but π‘₯(𝑠) is not.

The appearance of initial condition equation. This is necessary to ensure the existence of a solution.

Approximating functions

π‘₯(𝑠),π‘₯′(𝑠),π‘ž(𝑠),𝑦(𝑠),[π‘₯(𝑑)]𝑛1,[π‘₯(𝑑)]𝑛2,π‘˜1(𝑠,𝑑),π‘˜2(𝑠,𝑑)

with respect to TFs, π‘₯(𝑠)≅π‘₯𝑇(𝑠)𝑋 π‘₯′(𝑠)≅𝑋′𝑇𝑇(𝑠)=𝑇𝑇𝑋′

π‘ž(𝑠)≅ 𝑄𝑇𝑇(𝑠)=𝑇𝑇(𝑠)𝑄

𝑦(𝑠)≅ π‘Œπ‘‡π‘‡(𝑠)=𝑇𝑇(𝑠)π‘Œ [π‘₯(𝑑)]𝑛1≅𝑋𝑛1𝑇𝑇(𝑠)=𝑇𝑇(𝑠)𝑋𝑛1 [π‘₯(𝑑)]𝑛2≅𝑋𝑛2𝑇𝑇(𝑠)=𝑇𝑇(𝑠)𝑋𝑛2 π‘˜1(𝑠,𝑑)≅𝑇𝑇𝐾1𝑇(𝑑)

π‘˜2(𝑠,𝑑)≅𝑇𝑇𝐾2𝑇(𝑑)

Where 2π‘š-vectors 𝑋,𝑋′,𝑄,π‘Œ,𝑋𝑛1,𝑋𝑛2 and 2π‘š×2π‘š matrices 𝐾1 & 𝐾2 are TFs coefficients of

π‘₯(𝑠),π‘₯′(𝑠),π‘ž(𝑠),𝑦(𝑠),[π‘₯(𝑑)]𝑛1,[π‘₯(𝑑)]𝑛2,π‘˜1(𝑠,𝑑),π‘˜2(𝑠,𝑑) respectively.

Lemma

Let 2π‘š-vectors 𝑋 and 𝑋𝑛 be TFs coefficients of π‘₯(𝑠) and [π‘₯(𝑠)]𝑛 respectively. If

𝑋=(𝑋1𝑇𝑋2𝑇)𝑇=(𝑋10,𝑋11,…,𝑋1π‘š−1,𝑋20,𝑋21…𝑋2π‘š−1)𝑇, then

𝑋𝑛=(𝑋10,𝑋11,…,𝑋1π‘š−1,𝑋20,𝑋21…𝑋2π‘š−1)𝑇

Where 𝑛≥1 is a positive integer.

Proof:

Journal of the Maharaja Sayajirao University of Baroda ISSN: 0025-0422

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Volume-56, No.1 (IV) 2022

When 𝑛=1, , follows at once from [π‘₯(𝑠)]𝑛=π‘₯(𝑠).

Suppose that (4.16), holds for 𝑛, we shall deduce it for 𝑛+1.

Since [π‘₯(𝑠)]𝑛+1≅(𝑋𝑇𝑇(𝑠)).(𝑋1𝑇𝑇(𝑠))

=𝑋𝑇𝑇(𝑠)𝑇𝑇(𝑠)𝑋𝑛 =𝑋𝑇𝑋𝑛̃𝑇(𝑠)

we obtain 𝑋𝑇𝑋𝑛̃=(𝑋10𝑛+1,𝑋11𝑛+1,……,𝑋1π‘š−1𝑛+1,𝑋20𝑛+1,𝑋21𝑛+1,……,𝑋2π‘š−1𝑛+1)𝑇

Equation holds for 𝑛+1.

Components of 𝑿𝒏 can be Computed in terms of Components of Unknown Vector 𝑿

We substitute (1.15) into (1.14), we have π‘Œπ‘‡π‘‡(𝑠)≅𝑋′𝑇𝑇(𝑠)+𝑄𝑇𝑇(𝑠)𝑇𝑇(𝑠)𝑋+πœ†1𝑇𝑇(𝑠)𝐾1∫𝑇(𝑑)𝑇𝑇(𝑑)𝑋𝑛1𝑑𝑑+𝑠0πœ†2𝑇𝑇(𝑠)𝐾2∫𝑇(𝑑)𝑇𝑇(𝑑)𝑋𝑛2𝑑𝑑𝑠0

it follows that π‘Œπ‘‡π‘‡(𝑠)≅𝑋′𝑇𝑇(𝑠)+(𝑄̃ 𝑇(𝑠))𝑇𝑋+πœ†1𝑇𝑇(𝑠)𝐾1𝑋̃𝑛1∫𝑇(𝑑)𝑑𝑑+πœ†2𝑇𝑇(𝑠)𝐾2𝐷𝑋𝑛2𝑠0

Using Operational matrix 𝑃,

π‘Œπ‘‡π‘‡(𝑠)≅𝑋′𝑇𝑇(𝑠)+𝑋𝑇𝑄̃ 𝑇(𝑠)+πœ†1𝑇𝑇(𝑠)𝐾1𝑋̃𝑛1𝑃𝑇(𝑠)+πœ†2(𝐾2𝐷𝑋𝑛2)𝑇𝑇(𝑠)

In which πœ†1𝐾1𝑋̃𝑛1𝑃 is a 2π‘š×2π‘š matrix

𝑇𝑇(𝑠)πœ†1𝐾1𝑋̃𝑛1𝑃𝑇(𝑠)≅𝑋𝑛1𝑇̂𝑇(𝑠)

Where 𝑋̃𝑛1 is an 2π‘š-vector with components equal to the diagonal entries of the matrix πœ†1𝐾1𝑋̃𝑛1𝑃.

π‘Œπ‘‡π‘‡(𝑠)≅𝑋′𝑇𝑇(𝑠)+𝑋𝑇𝑄̃ 𝑇(𝑠)+𝑋𝑛1𝑇̂𝑇(𝑠)+πœ†2(𝐾2𝐷𝑋𝑛2)𝑇𝑇(+𝑄̃ 𝑋+𝑋𝑛1̂+ πœ†2𝐾2𝐷𝑋𝑛2≅π‘Œ

Where 𝑄̃ is a diagonal matrix, so 𝑄̃ 𝑇=𝑄̃.

𝑋′ must be computed in terms of 𝑋. π‘₯(𝑠)−π‘₯(0)=∫π‘₯′(𝜏)π‘‘πœπ‘ 0

≅∫𝑋′𝑇𝑇(𝜏)π‘‘πœπ‘ 0 ≅𝑋′𝑇𝑃𝑇(𝑠) π‘₯(𝑠)≅𝑋′𝑇𝑃𝑇(𝑠)+𝑋0𝑇𝑇(𝑠)

Where 𝑋0 is the 2π‘š- vector of the form

Journal of the Maharaja Sayajirao University of Baroda ISSN: 0025-0422

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Volume-56, No.1 (IV) 2022

𝑋0=[π‘₯0,π‘₯0,…π‘₯0]𝑇

Consequently,

𝑋≅𝑃𝑇𝑋′+𝑋0

Now, combining (1.19) and (1.20) and replacing ≅ with =, it follows that

(𝐼+𝑃𝑇𝑄̃)𝑋+𝑃𝑇𝑋𝑛1̂+πœ†2𝑃𝑇𝐾2𝐷𝑋𝑛2≅π‘ƒπ‘‡π‘Œ+𝑋0

Equation is a nonlinear system of 2π‘š algebraic equations for the 2π‘š unknowns 𝑋10,𝑋11,…𝑋1π‘š−1,𝑋20,𝑋21,…𝑋2π‘š−1.

Components of 𝑋𝑇=(𝑋1𝑇 𝑋2𝑇) can be obtainbed by an iterative method.

Hence, an approximate solution π‘₯(𝑠)≅𝑋𝑇𝑇(𝑠)

π‘₯(𝑠)≅𝑋1𝑇𝑇1(𝑠)+𝑋2𝑇𝑇2(𝑠)

Can be computed for equation (1.14) without using any projection method.

Conclusion

We investigated the numerical solution of nonlinear and singularly perturbed for Vulture integro-differential equations. Also, numerical solution of high-order and fractional nonlinear Volterra-Fredholm integro-differential equations and its error analysis are discussed. Finally, some numerical results of integro-differential equations are presented to illustrated the efficiency and accuracy of the proposed methods.

Reference

1. G.Yu.Mekhtieva, V.R.Ibrahimov “On one numerical method for solution of integro-differential equations”, Vestnik BSU, ser.phys.-math. Scien., 2003, No3, pp.21-27.(Russian).

2. H.Brunner, “Collection method for Volterra integral and Relation Functional Equations”, Cambridge University Press, Cambridge,2004.

3. P.Darania, E.Abadian, “A method for the numerical solution of the integro-differential equations”, Appl.Math. and Comput. 188(2007) 657-668.

4. B. Ahmad, S. Siva Sundaram, Existence Results For Nonlinear Impulsive Hybrid Boundary Value Problems involving Fractional Differential Equations, Non linear Analysis, hybrid System, 3(2009).

5. Z.B. Bai, H.S. Lii, Positive Solutions Of Boundary Valuve problems Of Nonlinear Fractional Differential Equations, J. Math Anal.Appl.311(2005)\

6. v. Lakshmikantham, D.D. Bainov And P.S. Simeonov, Theory Of Impulsive Differential Equations, modern Applied Mathematics (1989).

7. K.S. Miller, B.Ross, An Introduction To The Fractional Caculus And Fractional Differential Equations, Wiley, New york, 1993

Friday, 29 April 2022

CRIME DETECTION MODELLING BY USING NUMERICAL METHODS

 CRIME DETECTION MODELLING BY USING NUMERICAL METHODS

1 CRIME:

 

In most countries the detection of crime is the responsibility of the police though special law enforcement agencies may be responsible for the discovery of the particular type of crime.

 

Example: Customs departments may be charged with computing smuggling and related offenses.

 

Crime detection falls in to three distinguishable phases the discovery that a crime has been committed the identification of a suspect and the collection of sufficient evidence to indict the suspect before a court.

 

Example: Electronic eavesdropping surveillance interception of communication and infiltration of gangs.



Fig: 1 FLOWCHAT OF CRIME DEFELATION


1.3.  STEPS OF CRIMINAL CASE:

 

The 5 basic steps of a criminal proceeding are

 

·         Arrest

·         Preliminary hearing

·         Grand jury investigation

·         Arraignment in criminal court

·         Trial by jury

 

1.4.  CAUSES OF CRIME:

 

·         Poverty this is perhaps one of the most concrete reasons why people

·         commit crime

·         Peer pressure new form of concern in the modern world

·         Drugs always been highly criticized by critics

·         Politics

·         Religion ,family conditions, the society ,unemployment.

 

1.5.  THE CRIME SCENE SKETCH:

 

·         Measure and outline area

·         North should be at the top of the paper

·         Determine the scale

·         Take the longest measurement at the scene and divide it by the longest measurement of the paper used for the Sketching.

Ø  1/2″ = 1 small rooms.

Ø  1/8″ = 1 very large rooms.

Ø  1/8″ = 10 large land area.


 

 

  2. CRIME PREVENTION AND TECHNIQUES

 

2.1.  INVOLVES:

 

Recognition.


                    ↓

 

Identification

 

 

Individualization

 

                     ↓

 

Reconstruction

 

2.1.1  RECOGNITION:

 

  Scene survey documentation collection

 

2.1.2  IDENTIFICATION:

 

  Classification of evidence

 

2.1.3  INDIVIDUATION:

 

  Comparison testing evaluation and interpretation

 

2.1.4  RECONSTRUCTION:

 

  Sequencing events reporting and presenting


2.2.  THE CRIME SCENE SKETCH:

 

         Measure and outline area

         It doesn’t stretch

         Use conventional units of measurements

         Inches

         Feet

         Centimeters

         Meters

 

2.3.  CRIME SCENE RECONSTRUCTION:

 

         Data collection

         Conjecture

         Hypothesis formulation

         Testing

         Theory

 




3.FLOWCHART AND CRIME NOTES

 

The location of possible targets homes people as well as general environmental goes like levels of disorder housing density and surveillance researches also include knowledge offenders might have about target vulnerability for instance tricks learned from burglarizing nearby and what they found was two kinds of crime hotspots.

 

Supercritical which formed from a rapid chain reaction of law less ness and subcritical a large spike in a crime in an otherwise stable area in a supercritical situation small spikes in crime grow and spread when increased police force is applied new hotspots.

But off existing once they reform around small spikes in a crime to continue away from areas of police presence the crime is displaced police suppression is a cat and mouse game something very different happens when police are added to a sub critical hots


The surrounding are relatively stable so one suppression is applied the hotpots is reduced or eradicated completely and even when suppression efforts are removed the hotpots doesn’t really. Since strategy won’t work for both kinds of hotpots.

 

This key difference may help law enforcement tailor their crime strategies to different neighborliness ultimately thought hotpots maybe similar sizes and distribution

 

The research shows that looking at the dynamic of crime is important in gauging the best police response and that could be a fundamental step towards better prediction and crime prevention strategies and an even safer future for cities.




4.  NOTES OF CRIME:

 

Imagine someone is committing crime throughout local area on a regular basis may be they have committed 5 crimes in the last month at these locations how could we go about catching this person.

One thing we can do is try finding a patterns in crime location in order to make a prediction about the next one that can be tricky through since there likely a huge elements of randomness but decades ago Kim Ross mo. a PhD criminologist had another idea he tried to find a formula instead could find.



Where the criminal likely lives based on the past data he knows that criminals often don’t commit crimes right by their own home but also they don’t go too far away so from the data you can determine a quote hot zone fig

Fig HOT ZONE

Which is not too close or too far from the crime scene it has a high probability of the person living there this is his equation for determining those probabilities. I know it looks complex but its actually not as bad as you think like take this Pi, j parts.

To see the crime scene in map and put a gird over it any given squares will be in some row we will label i and column will label j, Pi, j is probability that the criminal lives in the square. How you calculate that value for any square is with this right side of the equation.


Formula for crime detection:

                      X function axis of the co-ordinates distance . Y= function axis of the co-ordinates distance . Where,

(| Xi-xn|+|Yj -yn|)f 1 𝑠𝑑 π‘‘π‘’π‘Ÿm

 

(2𝐡| Xi-xn|+|Yj -yn|) g 2 𝑛𝑑 π‘‘π‘’π‘Ÿπ‘š

 

Now take this denominator equation, (|Xi-xn |+|Yj -yn|) f this 1stpart just means take the arbitrary grid you are analysing and one of the crime scene and subtract these x corps donets which gives you this distance.

 

The absolute value just ensure that its positive then |Yj -yn| parts just says do the same thing with the y axis which gives us this length add those up and we get the distance between the gird and the crime scene no it’s not the straight – line distance.

 

If you cannot move to agonal and as we saw this term is in the denominator which means as that distance goes up the entire fraction and thus the probability go down this is expected because like .I said these criminals usually don’t go super far to commit a crime so a larger distance between our square and the crime scene means a smaller Probability the criminal lies.

 

There at least for this laughter but remember criminals don’t commit these crime close to this homes either and that where this side of the equation comes.


 

 

You have that same distance down here subtracted from something known as a buffer zone which is just a 2B constant determined by what works best with known data or past crime so as



distance goes up the entire denominator actually decreasing making the whole fraction.

 

Probability go up so physically if you are too close to the crime scene probability is low that the criminal lives there but as you get further the probability increase that is of course until you pass a certain point which is where the left side of the formula comes in again after the distance and these 2 fractions change in opposite ways which is essentially.

 

The balancing act that creeps the hot zone of high probability that isn’t too close and isn’t too far from the crime scene for is sort of a constant that I am not going to go in to i j and that g, f and B are constant. That just make certain parts of this equation matter more than other or they add more weights to certain parts then lastly this part.

 

We calculated these 2 fractions for every single crime committed and add the results do this for square on our gird and we create a heat map of probability. Actually is the equation output based on real crimes of a serial killer from the 70s named Richard chase you can see the crime locations in green and the formula predicts his residence to be somewhere in this dark region his actual residence is plotted here in purple exactly as expected so that least in the case Rasco’s formula works. 

 5.   CRIME SCENE CONTROL



The actions which the first arriving officer at the crime scene takes to make sure that the integrity of the scene maintained. Control also includes preventing people at the scene from becoming combatants and separating witnesses.

5.1  DRAWBACKS:

·         No bobby on the beat

·         Local police officer in the local community

·         Large amount of data but is there a significant impact on detecting and reducing crime overal


 

 

5.2  BENEFITS:

·         Administrative duties completed more quickly

·         Tools available to help track down criminals

·         Communication improved

·         Evidence collection tracking analysis and availability improved

·        



Amount of data available.

5.3  SCALING THE INVESTIGATION TO THE EVENT:

·         The crime scene must be secured preserved and recorded until evidence is collected

·         Existing contamination must be considered and recorded

·         Cross contamination must be prevented

·         Exhibits must be identified preserved collected and secured to pressure the chain of continuity

5.4  CRIME SCENE ANALYSIS PROCESS:

·         Crime analysts study crime reports arrests reports and police cells for service calls for service to identify emerging patterns series and trends as quickly as possible.

·         The analyse these phenomena for all relevant factors sometimes predict or forecast future occurrence and issue bulletins reports and alert to their agencies.


5.5  CRIME SCENE CONTROL:

 

·         The actions which the first arriving officer at the crime scene takes to make sure that the integrity of the scene is maintained.

·         Control also includes preventing people at the scene from becoming combatants and separating witnesses.

 

5.6.1  CRIME SCENE MAPPING:

 

·         Triangulation- uses to two points at the crime scene to map each piece of evidence

·         Coordinate or grid divides the crime scene into squares for mapping

·         Suspended polar coordinate-for use in mapping evidence in a hole

·         Baseline- set a north or south line and measure each piece of evidence from this line.

 

5.6.2  MICROSCOPIC CRIME SCENE:

 

·         Based on the size

·         Trace evidence

·         Gunshot residue

·         Tire treads

·         Hair samples

·         Mites found in clothes

 

5.6.3  CRIME SCENE DOCUMENTATION:

 

·         Take notes at the crime scene

·         Videotape the crime scene

·         Photograph the crime scene