Open Access Original Research Article

The Existence of Random Attractor for Stochastic Suspension Bridge Equation

Xiao Bin Yao

Asian Research Journal of Mathematics, Page 11-23
DOI: 10.9734/arjom/2020/v16i230172

This paper is aimed at an extensible suspension bridge equation with additive noise and linear memory. For the suspension bridge equations without additive noise and memory, there are many classical results. However, the extensible suspension bridge equations with both additive noise and linear memory were not studied before. The object of this paper is to provide a result on the random attractor to the above problem using compactness translation theorem and decomposition technique.

Open Access Original Research Article

Certain Geometric Aspects of a Class of Almost Contact Structures on a Smooth Metric Manifold

Ojiema M. Onyango, Mengich Beatrice, Wafula A. Wanambisi

Asian Research Journal of Mathematics, Page 24-38
DOI: 10.9734/arjom/2020/v16i230173

The classication of Smooth Geometrical Manifolds still remains an open problem. The concept of almost contact Riemannian manifolds provides neat descriptions and distinctions between classes of odd and even dimensional manifolds and their geometries. We construct an almost contact structure which is related to almost contact 3-structure carried on a smooth Riemannian manifold (M, gM) of dimension (5n + 4) such that gcd(2, n) = 1. Starting with the almost contact metric manifolds (N4n+3, gN) endowed with structure tensors (ϕi, ξj , ηk) such that 1 ≤ i, j, k ≤ 3 of types (1, 1), (1, 0), (0, 1) respectively, we establish that there exists a structure (ϕ4, ξ4, η4) on (N4n+3 ⊗ Rd) ≈ M; gcd(4, d) = 1, d|2n + 1, constructed as linear combinations of the three structures on (N4n+3, gN) . We study some algebraic properties of the tensors of the constructed almost contact structure and further explore the Geometry of the two manifolds (N4n+3⊗Rd) ≈ M and N4n+3 via a !submersion F : (N4n+3 ⊗Rd) ↩→ (N4n+3) and the metrics gM respective gN between them. This provides new forms of Gauss-Weigarten's equations, Gauss-Codazzi equations and the Ricci equations incorporating the submersion other than the First and second Fundamental coecients only. Fundamentally, this research has revealed that the structure (ϕ4, ξ4, η4) is constructible and it is carried on the hidden compartment of the manifold M∼=(N4n+3 ⊗ Rd) (d|2n + 1) which is related to the manifold (N4n+3).

Open Access Original Research Article

Forecasting of the Nigeria Stock Returns Volatility Using GARCH Models with Structural Breaks

Yakubu Musa, Ibrahim Adamu, Nasiru Sani Dauran

Asian Research Journal of Mathematics, Page 39-50
DOI: 10.9734/arjom/2020/v16i230174

This study examines the stock returns series using Symmetric and Asymmetric GARCH models with structural breaks in the presence of some varying distribution assumptions. Volatility models of Symmetric GARCH (1,1), Asymmetric Power GARCH (1,1) and GJR-GARCH(1,1) models were considered in estimating and measuring shock persistence,  leverage effects and mean reversion rate with structural breaks considering dummy variable  for these structural changes and varying distributions . The skewed student-t distribution is considered best distribution for the models; moreover findings showed the high persistence of shock in returns series for the estimated models. However, when structural breaks were incorporated in the estimated models by including dummy variable in the conditional variance equations of all the models, there was significant reduction of shock persistence parameter and mean reversion rate.  The study found the GJR-GARCH (1,1) with skewed student-t distribution best fit the series. The volatility was forecasted for 12 months period using GJR-GARCH (1,1) model and the values are compared with the actual values and the results indicates a continuous increase in unconditional variance.

Open Access Original Research Article

Stability and Controllability of Nonlinear Systems

S. T. Cotterell, I. Davies, L. C. Abraham

Asian Research Journal of Mathematics, Page 51-60
DOI: 10.9734/arjom/2020/v16i230175

This paper is aimed at establishing new stability and controllability results for nonlinear systems. The approach is to use the Lyapunov indirect method to obtain the stability of the equilibrium solution of the uncontrolled nonlinear system by applying the Jacobi’s linearization method and the controllability of the controlled system obtained by the rank criterion for properness. Example is given with a real-life application to illustrate the effectiveness of the theoretical results.

Open Access Review Article

The Coverage Issues in WSNs

Jyoti Rani, Vishal Anand

Asian Research Journal of Mathematics, Page 1-10
DOI: 10.9734/arjom/2020/v16i230171

Aim: Wireless Sensor Networks is one of the hot research topic in previous years due to its wide contribution in emerging industry that is Internet of Things. A wireless sensor network is a network of tiny devices, which can gather the information from surrounding and then successfully communicate it via wireless link. WSNs are widely used for monitoring targets in given field of interest. Most popular area of research in Wireless Sensor Networks is coverage. This paper focus on coverage issues in Wireless Sensor Networks.

Study Design: Various Issues in WSNs being studied and analyzed.

Place and Duration of Study: Swami Parmanand College Lalru, between May 2019 to December 2019.

Methodology: It included following steps:-

  • Survey of the literature related to the proposed work.
  • Comparison of different types of WSNs and challenges and issues related to them.
  • Detailed study of coverage issue involved in implementation of WSN.

Results: Coverage selection depends on the system requirement. Each coverage has its own advantages and disadvantages related to its implementation.

“Table 2: Comparison between Various WSN and challenges related to them” it discusses about various types of WSNs and the challenges related to each one of them.

Conclusion: Coverage in WSNs can be defined on how well the sensor nodes monitor the targets in given field of interest. Each application comes with different set of coverage requirements; hence, deployment strategies are chosen based on the requirements.