B.S. Lalli’s research while affiliated with Cairo University and other places

What is this page?


This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.

Publications (114)


Stability of n-Dimensional Inhomogeneous Delay Differential Equations
  • Chapter

January 2023

·

1 Read

B.S. Lalli

·

S.R. Grace

Existence of Oscillatory and Nonoscillatory Solutions for a Class of Neutral Functional Differential Equations

September 1997

·

33 Reads

·

3 Citations

this paper is to develop an existence theory enabling us to construct various types of oscillatory and nonoscillatory solutions of neutral equations of the form (A). We make use of the observation that the associated unperturbed equation






Oscillation criteria for nonlinear second order elliptic differential equations

January 1996

·

8 Reads

·

19 Citations

Chinese Annals of Mathematics Series B

The second order elliptic differential equations Li(y; x) = ∑i,j=1n Di[Aij(x)Djy]+p(x)f(y) = 0 (1.1) and L2(y; x) = δy+p(x)|y|γsigny = 0, 1 ≠ γ > 0 (1.2) are considered in an exterior domain Ω ⊂ Rn , n ≥ 2, where p can chang sign. Some new sufficient conditions for the oscillation of solutions of (1.1) and (1.2) are established.




Necessary and sufficient conditions for the oscillations of a multiplicative delay logistic equation

March 1995

·

6 Reads

·

20 Citations

Quarterly of Applied Mathematics

Necessary and sufficient conditions are presented for the oscillation of all positive solutions of the multiplicative delay logistic equation dN(t)dt=r(t)N(t)(1j=1m(N(gj(t)K))dN(t)dt=r(t)N(t)(1j=1m(N(gj(t)K)) d N ( t ) d t = r ( t ) N ( t ) ( 1 − ∏ j = 1 m ( N ( g j ( t ) K ) ) \frac {{dN\left ( t \right )}}{{dt}} = r\left ( t \right )N\left ( t \right ) \left ( {1 - \prod \limits _{j = 1}^m { \left ( {\frac {{N\left ( {g_j}\left ( t \right ) \right .}}{K}} \right ) } } \right ) about the positive equilibrium K K . The cases when r ( t ) = r r\left ( t \right ) = r and g j ( t ) = t − τ j {g_j}\left ( t \right ) = t - {\tau _j} or g j ( t ) = [ t − k j ] {g_j}\left ( t \right ) = \left [ {t - {k_j}} \right ] , [•] denoting the greatest integer function, where r , τ j r, {\tau _j} , and k j {k_j} are positive constants, j = 1 , 2 , . . . , m j = 1, 2,...,m , are also included.


Citations (72)


... For linear NDEs, Gopalsamy et al. [39] established adequate conditions for every solution to oscillate, which are derived along with some comparison results. Candan [40] studied the oscillatory properties of mixed NDEs with distributed deviating arguments. ...

Reference:

Comparison Theorems for Oscillation of Higher-Order Neutral Delay Differential Equations
Oscillation of odd order neutral differential equations
  • Citing Article
  • January 1992

Czechoslovak Mathematical Journal

... Recently there has been a great interest in studying the oscillatory and asymptotic behavior of third order differential equations, see for example [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23], and the references cited therein. In [1,4,7,8,9,15,20,23], the authors studied the oscillatory behavior of solutions of equation (1.1) when b(t) ≡ 0, c(t) ≡ 0 and p(t) ≡ 0. In [5,6,10,11,17,18,19,21], the authors studied the oscillatory behavior of solutions of equation (1.1) when c(t) ≡ 0 and p(t) ≡ 0. In [2,13,14,22], the authors discussed the oscillatory behavior of all solutions of equation (1.1) when α = β = γ = 1. ...

Oscillation theorems for certain neutral differential equations
  • Citing Article
  • January 1988

Czechoslovak Mathematical Journal

... During the past period, many papers appeared on the oscillatory behavior of differential equations of neutral and delay type. Investigations by Zhang et al. [11], Li et al. [12][13][14][15], Baculikova et al. [16], and Grace and Lalli [17] have yielded techniques and methodologies aimed at enhancing the oscillatory attributes of these equations. Furthermore, the work of Zhang et al. and Agarwal et al. [6,[18][19][20][21] has expanded this inquiry to encompass differential equations of the neutral variety. ...

Oscillation theorems for 𝑛th order nonlinear differential equations with deviating arguments
  • Citing Article
  • January 1984

Proceedings of the American Mathematical Society

... The oscillatory theory as a part of the qualitative theory of differential equations has been developed rapidly in the last decades, and there has been a great deal of work on the oscillatory behavior of differential equations; see e.g. (Agarwal et al. 2010;Beqiri and Koci 2012;Bihari 1963;Elabbasy and Elsharabasy 1997;Elabbasy and Elhaddad 2007;Grace et al. 1984Grace et al. , 1988Grace and Lalli 1987, 1989, 1990Grace 1989Grace , 1990Grace , 1992Greaf and Spikes 1986;Graef et al. 1978;Lee and Yeh 2007;Kamenev 1978;Kartsatos 1968;Li and Agarwal 2000;Meng 1996;Nagabuchi and Yamamoto 1988;Ohriska and Zulova 2004;Ouyang et al. 2009;Philos 1983Philos , 1984Philos , 1985Remili 2010;Tiryaki and Basci 2008;Tiryaki 2009;Temtek and Tiryaki 2013;Yan 1986;Yibing et al. 2013a, b;Zhang and Wang 2010). Remili (2010), studied the equation Zhang and Wang (2010), studied the following equation ...

On the second order nonlinear oscillations
  • Citing Article
  • January 1987

... In this spirit our main result unifies some earlier Kartsatos' results on the maintenance of oscillations under the effect of a "small" or "periodic-like" forcings and at the same time extends them to more general forcing functions. For other related results concerning Eq. (1) and corresponding functional differential equations and inequalities we refer the reader to the papers of Chen and Yeh [2,3], Foster [4], Grace and Lalli [5,6], Jaros [7,8], Kawano, Kusano and Naito [13], Kusano et al. [14][15][16], McCann [17], Onose [18,19] and True [21]. ...

Corrigendum to ”On oscillation of solutions of higher order differential retarded inequalities”
  • Citing Article
  • January 1984

Houston Journal of Mathematics

... The presence of the damping term in (1.8) calls for a modified approach to the study of the oscillatory properties of solutions. A number of oscillation criteria for (1.8) can be found, for example, in papers by Grace [10,12], Grace and Lalli [13][14][15][16][17][18][19][20][21], Grace, Lalli and Yeh [22], Kirane and Rogovechenkov [30,31], Li and Agarwal [39], Li and Zhang [41], Rogovechenkov [45], Wong [52], Yan [54] and Yeh [55]. However the common restriction f 0 (x) ≥ k > 0 is required, which does not hold, for example, for ...

An oscillation criterion for second order sublinear ordinary differential equations with damping term
  • Citing Article
  • January 1987

Bulletin of the Polish Academy of Sciences Mathematics

... He was able to provide conditions that guarantee the oscillation of all bounded solutions. By establishing a criterion that guarantees the oscillation of all solutions, Grace and Lalli [19] tested the oscillation of DDEs using the Riccati technique. Later, Zhang and Ladde [20] extended the results in [19] to equations with a middle term. ...

An oscillation criterion for nth order nonlinear differential equations with retarded arguments
  • Citing Article
  • March 1983

Czechoslovak Mathematical Journal