Browsing by Author "Ngari, Cyrus Gitonga"

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Aperture Maximization with Half-Wavelength Spacing, via a 2-Circle Concentric Array Geometry that is Uniform but Sparse
    (Journal of Advances in Mathematics and Computer Science, 2019-05-25) Kinyili, Musyoka; Kitavi, Dominic Makaa; Ngari, Cyrus Gitonga
    This paper proposes a new sensor-array geometry (the 2-circle concentric array geometry), that maximizes the array’s spatial aperture mainly for bivariate azimuth-polar resolution of direction-of-arrival estimation problem. The proposed geometry provides almost invariant azimuth angle coverage and offers the advantage of full rotational symmetry (circular invariance) while maintaining an inter-sensor spacing of only an half wavelength (for non-ambiguity with respect to the Cartesian direction cosines). A better-accurate performance in direction finding of the proposed array grid over a single ring array geometry termed as uniform circular array (UCA) is hereby analytically verified via Cram´er-Rao bound analysis. Further, the authors demonstrate that the proposed sensor-array geometry has better estimation accuracy than a single ring array.
  • No Thumbnail Available
    Item
    Socioeconomic Impact of Establishment of University of Embu on Small Scale Farmers in Nthambo Sub-Location, Kenya
    (Asian Journal of Probability and Statistics, 2018-11) Akelo, Gogo Jacqueline; Ngari, Cyrus Gitonga
    The University of Embu is one of the fast developing and recently chartered University in Kenya. It is located in Nthambo sub-location, which is an agricultural potential area. Universities establishment have considerable influence on the activities of community that stays around it. Despite the fact that several studies have been conducted on the socioeconomic impact of establishment of different Universities to the community they reside in, a research on the socioeconomic impact of establishment of University of Embu on small scale farmers in their agricultural activities have never been done. Given that the University of Embu has been established on the agricultural potential area, this study sought to investigate the impact of the establishment of University of Embu on agricultural resources and productivity, describe the community diversity and living standards of the community. Methodology used in this research was descriptive survey design and stratified random sampling technique obtaining a sample of 100 households which was proportionate to the population. Using SPSS software for cross-tabulation, the results indicated that: the rate of both livestock and crop production have been declining with supporting evidence of (60.2%) and (66%) of the households respectively, the community was diverse (87.2%) with majority being university students (68.1%), most of the small scale farmers had access to electricityconnection (78.1%), even though farming activity remains main economic activity of community within the area, it has been declining from (95.3%) to (53.2%), business activities have increased from (3.5%) to (41.5%), most of the households (54.3%) have constructed rental houses majorly to earn more money (70.2%). The researchers recommend that Embu County government should adopt a policy such that the communities surrounding University of Embu must develop, implement and enforce mechanisms for effective preservation of productive agricultural land (i.e. Urban growth boundaries, purchase of development rights, exclusive agricultural zoning among others).
  • No Thumbnail Available
    Item
    A Theoretical Model of Corruption Using Modified Lotka Volterra Model: A Perspective of Interactions between Staff and Students
    (Journal of Advances in Mathematics and Computer Science, 2020-08) Kawira, Mercy; Ngari, Cyrus Gitonga; Karanja, Stephen
    Corruption is the misuse of power or resources for private gain. This undermines economic development, political stability, and government legitimacy, the society fabric, allocation of resources to sectors crucial for development, and encourages and perpetuates other illegal opportunities. Despite Mathematical modeling being a powerful tool in describing real life phenomena it still remains unexploited in the fight of corruption menace. This study uses Lotka Volterra, predator-prey equations to develop a model to describe corruption in institutions of higher learning, use the developed model to determine its equilibria, determine the condition for stability of the equilibria and finally carry out the simulation. The corrupt students and staff act as predators while their non-corrupt counterparts act as prey in the paper. Theory of ordinary differential equations was used to determine steady states and their stability. Mathematica was used for algebraic analysis and Matlab was used for numerical analysis and simulation. Analytical result suggested multiple steady state however numerical result confirmed that the model has four steady states. Numerical bifurcation analysis suggests the possibility of backward of corrupt staff when is about 39. Numerical simulation points to an increasing trend on corrupt staff and decrease trend on corrupt student. This study concludes that more focus should be put to staff than students in curbing the spread of corruption. Future study should strive to fit this model in real data.