Browsing by Author "Kilavo, Hassan"

Now showing 1 - 5 of 5
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    A dual band frequency reconfigurable metasurface antenna
    (IGI Global, 2021) Ulomi, George Shilela; Kilavo, Hassan
    In this chapter, a single feed metasurface antenna with smooth dual-band frequency reconfiguration is proposed. The designed antenna has a simple and compact structure to be used in portable wireless communication devices. The antenna consists of two circular layers of substrate material placed one on top of the other. The lower layer is printed with a rectangular patch antenna in one side, and the other side is a ground plane. The upper substrate layer lay on top of patch antenna side is printed with a number of unit-cells on its upper side. To achieve frequency reconfiguration, the upper substrate layer is mechanically rotated at an angle θz in a clockwise direction along Z-axis. Based on rotation angle, the antenna scattering parameters (S11 and S21) of the unit cell are subjected to change which thereby affects relative permittivity of the upper layer resulting to a frequency reconfiguration.
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    Electrical & electronic engineering research article performance of soft viterbi decoder enhanced with non-transmittable codewords for storage media
    (Cogent Engineering, 2018) Kilavo, Hassan; Kisangiri, Michael; Salehe, Mrutu
    The introduction of Non-Transmittable Codewords (NTCs) into Viterbi Algorithm Decoder has emerged as one of the best ways of improving performance of the Viterbi Algorithm Decoder. However, the performance has been tested only in hard decision Viterbi Decoder in telecommunication systems, but not in soft decision Viterbi Decoder and storage media. Most storage media use Reed Solomon (RS) Algorithm Decoder. Yet, the field experience still shows failure of the algorithm in correcting burst errors in reading data from the storage media; leading into data loss. This paper introduces the Soft Viterbi Algorithm Decoding enhanced with Non- Transmittable Codewords for storage media. Matlab software was used to simulate the algorithm and the performance was measured by comparing residual errors in a data length of one million bits. Additive White Gaussian Noise model was applied to distort the stored data. The performance comparison was made against the Reed Solomon code, Normal Soft Viterbi and Hard decision Viterbi enhanced with NTCs. The results showed that the Soft Viterbi Algorithm enhanced with NTCs performed remarkably better by 88.98% against RS, 84.31% against Normal Soft Viterbi and 67.26% against Hard Viterbi enhanced with NTCs.
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    The impact of teaching computer programming in Tanzanian primary schools
    (Taylor & Francis, 2022) Kilavo, Hassan; Kondo, Tabu S.; Hassan, Feruzi
    Today computing is intricate in all aspects of our lives, beginning with communications and education to banking, information security, health, shopping, and social media. Development of the computing is proportional to the development of software which is becoming a serious part of all daily lives. This paper, therefore, assessed the impact of teaching Computer Programming Language in Tanzanian primary schools. To achieve this, a new tool for teaching and learning a computer programming language was developed. Furthermore, a two-tier approach was adopted where the training started on an algorithm first, then if, loops and case conditionals as the third concept inside the first tier. On the other hand, variables, lists, and functions are hooked on the second tier. Results indicate that students acquired together reasoning learning in a conceptual argument of view and skill performance. Students were able to accomplish the expertise to practice or apply the theories of programming knowledge in programming-connected tasks.
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    Reverse social engineering to counter social engineering in mobile money theft: a tanzanian context
    (Routledge, 2020) Kilavo, Hassan; Mselle, Leonard J.; Rais, Ramadhani I.; Mrutu, Salehe I
    Social engineering entails deception where one manipulates individuals into divulging confidential or any personal information that may be used for fraudulent purposes. In mobile money theft, the attackers plan a “lure” to tempt a victim directly, via mobile phones; mostly to gain money by proposing a phony undertaking. The victim is often asked to pay some money to facilitate a lucrative undertaking, which in reality is phony. Once the victim has paid the money, the attackers become inaccessible. Reverse social engineering entails deception of the predator by the pray in order to capture or discourage the predator. Through a case study, this paper investigates and presents an incident where a victim of mobile social engineering attempts to reverse the process in order to arraign the attackers.
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    Securing relational databases against security vulnerabilities: a case of microsoft SQL server and postgreSQL
    (Routledge, 2021) Kilavo, Hassan; Mrutu, Salehe I.; Dudu, Robert G.
    This study evaluates mechanisms to secure relational databases against security vulnerabilities and utilized PostgreSQL and Microsoft SQL Server due to data breach incidences reported across the world. Emulation experiments with documentary review were employed to collect necessary study data. Identification of security features and vulnerabilities that are found to affect the data tier of the web applications were examined. The findings from the study have shown that Microsoft SQL Server is more security feature-rich in terms of Confidentiality, Integrity, and Availability compared to PostgreSQL and Microsoft SQL Server is more resilient to security attacks in its default behavior compared to PostgreSQL.