Open Access Original Research Article

From Two to One Index Isomorphism in Optimization Program for Quarterly Disaggregation of Annual Times Series

Raïmi Aboudou Essessinou, Guy Degla, Babacar Mbaye Ndiaye

Journal of Advances in Mathematics and Computer Science, Page 1-15
DOI: 10.9734/jamcs/2019/v34i1-230199

The quarterly disaggregation of an annual economic aggregate, by a mathematical method with a cyclical indicator, gives rise to a problem of minimization to make the quarterly economic aggregate smooth. This involves two indexes for the quarter and the year, which sometimes can make the resolution algorithm less efficient if the problem is large. In this paper we propose a method of indexing quarterly variables based on an isomorphic transformation of a two-index program into a one-index program, in order to minimize the cost of the algorithm of resolution. This method of continuous indexing of variables, applied to national accounts, shows that the algorithm with a single index is more efficient than the algorithm with two indexes when solving the optimization program of the quarterly disaggregation.

Open Access Original Research Article

On Quasi-Hemi-Slant Riemannian Submersion

S. Longwap, F. Massamba, N. E. Homti

Journal of Advances in Mathematics and Computer Science, Page 1-14
DOI: 10.9734/jamcs/2019/v34i1-230200

We recall the notions of invariant, anti-invarian, semi-invariant, slant, semi-slant, quasi-slant and hemi-slant Riemannian submersions from almost Hermitian manifolds to a Riemannian manifolds. In this paper we contruct a Riemannian submersion which generalizes hemi-slant, semi-slant and semi-invariant Riemanian submersions from almost Hermitian manifold to a Riemannian manifold and study its geometry.

Open Access Original Research Article

Secure Electronic Voting Using a Hybrid Cryptosystem and Steganography

Oladotun O. Okediran, Adeyemi A. Sijuade, Wajeed B. Wahab

Journal of Advances in Mathematics and Computer Science, Page 1-26
DOI: 10.9734/jamcs/2019/v34i1-230201

Conventional voting techniques have been employed over the years in most elections. However, each of these techniques has attendant short comings. The existing conventional voting systems have been subjected to gross abuse and irregularities. Electronic voting (e-voting) which is emerging as an alternative to these conventional voting systems, though highly promising, is not also totally free of flaws; information security issues bordering on privacy, integrity and verifiability of the electronic ballots casted are still significant in most implementations of e-voting systems. In this paper, we developed a security scheme that was based on a hybrid Rivest-Sharma-Adleman (RSA) algorithm and Advance Encryption Standard (AES) algorithm with Least Significant Bit (LSB) replacement algorithm for securing ballot information in an e-voting system. An e-voting system with multiple voting channels which includes poll site voting, mobile voting and remote internet voting was developed in the contextual Nigerian scenario. The electronic ballots casted via the system during experimental usage were encrypted using the hybrid RSA-AES algorithm to circumvent the problems of privacy, integrity and verifiability associated with many e-voting systems. The encrypted ballots were then hidden using LSB replacement algorithm to improve their integrity. The image quality of the cover image used and stego image obtained from the security scheme developed was quantitatively assessed using Peak Signal to Noise Ratio (PSNR), Mean Square Error (MSE) and Correlation. Furthermore, a performance evaluation based on users' perception of the developed e-voting system showed that the system satisfied most of the generic security requirements for electronic voting.

Open Access Original Research Article

Wong-Zakai Method Applications for Explicitly Solvable Stochastic Differential Equations

Süleyman Şengül, Mehmet Merdan

Journal of Advances in Mathematics and Computer Science, Page 1-12
DOI: 10.9734/jamcs/2019/v34i1-230202

In this study, three Ito stochastic differential equations with multiplicative noise are investigated with Wong-Zakai method. The stochastic differential equations are also analyzed by Euler-Maruyama, Milstein and Runge Kutta stochastic approximation methods. The relative errors of these three methods are compared and the performance of Wong-Zakai method is shown alongside numerical results.

Open Access Original Research Article

Improving Foresight Predictions in the 2002-2018 NFL Regular-Seasons: A Classic Tale of Quantity vs. Quality

E. Cabral Balreira, Brian K. Miceli

Journal of Advances in Mathematics and Computer Science, Page 1-14
DOI: 10.9734/jamcs/2019/v34i1-230203

Utilizing a modied Bradley-Terry model, we develop a method of making foresight predictions of 2002-2018 NFL games by incorporating a home-eld parameter into previously established ranking models. Knowing only the home team and score of each contest, and taking into account previous predictions, we optimize this parameter considering one of two things: the quantity of correct picks to date or the quality of predictions to date as measured by a quadratic scoring
function. Our main results establish that optimization of quality-rather than quantity-when making a prediction has higher overall accuracy.