UDOM IR :: Browsing by Author "Mrutu, Salehe I."

Browsing by Author "Mrutu, Salehe I."

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A review on deep learning aided pilot decontamination in massive MIMO
(Informa UK Limited, 2024-02-29) Victor, Crallet M.; Mvuma, Alloys N.; Mrutu, Salehe I.
In multi-antenna systems, advanced techniques such as massive multiple-input multiple-output (MIMO), beamforming, and beam selection depend heavily on the accurate acquisition of the channel state. However, pilot contamination (PC) can be a major source of interference which degrades they are performance. Moreover, the severity of PC increases as more pilots are reused between users in the wireless systems. Researchers have shown that PC can be mitigated by using deep learning (DL) approaches. Nevertheless, when minimizing PC, the examination that identifies the applications and factors that distinguish these DL approaches is still limited. This paper reviews these DL approaches and the improvements needed to enhance their performance. Simulation results confirm that DL networks that learn to predict the channels directly have superior performance under PC.
A review on deep learning aided pilot decontamination in massive MIMO
(Informa UK Limited, 2024) Victor, Crallet M.; Mvuma, Alloys N.; Mrutu, Salehe I.
In multi-antenna systems, advanced techniques such as massive multiple-input multiple-output (MIMO), beamforming, and beam selection depend heavily on the accurate acquisition of the channel state. However, pilot contamination (PC) can be a major source of interference which degrades they are performance. Moreover, the severity of PC increases as more pilots are reused between users in the wireless systems. Researchers have shown that PC can be mitigated by using deep learning (DL) approaches. Nevertheless, when minimizing PC, the examination that identifies the applications and factors that distinguish these DL approaches is still limited. This paper reviews these DL approaches and the improvements needed to enhance their performance. Simulation results confirm that DL networks that learn to predict the channels directly have superior performance under PC.
Assessment of non transmittable codewords enhancement to viterbi algorithm decoding
(LJS Publishing, 2014) Mrutu, Salehe I.; Sam, Anael; Mvungi, Nerey H.
Researchers have shown that practical mobile communication channels introduce errors that are concentrated in a certain locality rather than random errors. These are burst errors caused by deep fading of the wireless channel or a lightning strike. The existing Viterbi Algorithm (VA) capable of correcting random errors is inefficient in correcting burst errors and therefore resulting in unacceptable amount of residual errors. This paper presents an assessment of Non-Transmittable Codewords (NTCs) enhancement technique to VA in decoding the received signals subjected to burst errors that may occur in poor channels. A hard decision, 1/2 rate and constraint length K is equal to 3 Viterbi Algorithm decoding technique, Binary Phase-Shift Keying (BPSK) and Additional White Gaussian Noise (AWGN) are components used in MATLAB software based simulation when assessing the proposed technique. Applying 6NTCs to VA decoder enables the decoder to reduce 83.7 percent of its residual errors. However, the technique reduces the encoder’s data transmission rate from 1/2 to 1/6.
Bandwidth aware FEC algorithms for wireless communication systems
(Academic Hosting & Event Management Solutions, 2013) Mrutu, Salehe I.; Kalolo, Sadath; Byanyuma, Mastidia; Nyakyi, Christina; Sam, Anael
Forward Error Correction (FEC) codes used by receivers to correct transmission errors without retransmission add a considerable amount of redundant bits to data bits. The addition of redundant bits lowers the overall network throughput, thus increasing the demand for more required bandwidth. In this paper we investigate and discuss various techniques used in FEC and show their effects to data communication in terms of bandwidth utilization. Additionally we propose improvement of (2, 1, 2) Convolutional encoder to (3, 2, 3) encoder. The proposed improvements increase the code rate from 1/2 to 2/3 hence reducing error control information and increasing bit rate. The received codeword can be decoded by Soft-Output Viterbi Algorithm.
Computer-assisted instruction for transparent language reading for K-3 learners with intellectual, developmental and learning disabilities: a systematic review with meta-analysis
(Emerald, 2024-01-15) Liana, Leyla Hamis; Mrutu, Salehe I.; Mselle, Leonard
Purpose Computer-assisted instruction (CAI) has been used to combat reading challenges, namely reading accuracy and rate for learners with intellectual, developmental and learning disabilities (IDLD). Whilst most reading CAI effectiveness has been studied in English, other transparent languages have less evidence. This study provides a systematic review and meta-analysis of CAI effectiveness for transparent language reading for K-3 learners with IDLD. Design/methodology/approach This study systematically reviews academic peer-reviewed studies from 2010 to 2023 with either randomised controlled treatment (RCT) or single-case treatments. Articles were searched from the ACM Digital Library, Google Scholar, IEEE Xplore, ERIC, PsychINFO and Science Direct databases, references and systematic review articles. Reading component skills effect sizes were computed using the random effect sizes model. Findings 11 RCT studies of reading CAI for transparent languages with 510 learners with IDLD were found. A random effect sizes (Cohen’s d) of CAI on individual reading component skills were d = 0.24, p-value = 0.063 and confidence interval (CI) 95% (−0.068–0.551) for phonics and phonemic awareness d = 0.41, p-value = 0.000 and CI 95% (0.175–0.644). Given an average intervention dosage of 1.8 h weekly for a maximum of 16 weeks, CAI had better retention with d = 1.13, p-value = 0.066 and CI 95%(−0.339–2.588). However, these results must be interpreted with a concern of only using published studies. Originality/value The study contributes to quantitative CAI effectiveness for transparent language reading components for learners with IDLD.
Computer-assisted instruction for transparent language reading for K-3 learners with intellectual, developmental and learning disabilities: a systematic review with meta-analysis
(Emerald, 2024) Liana, Leyla Hamis; Mrutu, Salehe I.; Mselle, Leonard
Purpose – Computer-assisted instruction (CAI) has been used to combat reading challenges, namely reading accuracy and rate for learners with intellectual, developmental and learning disabilities (IDLD).Whilst most reading CAI effectiveness has been studied in English, other transparent languages have less evidence. This study provides a systematic review and meta-analysis of CAI effectiveness fortransparent language reading for K-3 learners with IDLD. Design/methodology/approach – This study systematically reviews academic peer-reviewed studies from 2010 to 2023 with either randomised controlled treatment (RCT) or single-case treatments. Articles were searched from the ACM Digital Library, Google Scholar, IEEE Xplore, ERIC, PsychINFO and Science Direct databases, references and systematic review articles. Reading component skills effect sizes were computed using the random effect sizes model. Findings – 11 RCT studies of reading CAI for transparent languages with 510 learners with IDLD were found. A random effect sizes (Cohen’s d) of CAI on individual reading component skills were d 5 0.24, p-value 5 0.063 and confidence interval (CI) 95% ( 0.068–0.551) for phonics and phonemic awareness d 5 0.41, p-value 5 0.000 and CI 95% (0.175–0.644). Given an average intervention dosage of 1.8 h weekly for a maximum of 16 weeks, CAI had better retention with d 5 1.13, p-value 5 0.066 and CI 95%( 0.339–2.588). However, these results must be interpreted with a concern of only using published studies. Originality/value – The study contributes to quantitative CAI effectiveness for transparent language reading components for learners with IDLD.
Design of soft viterbi algorithm decoder enhanced with non-transmittable codewords for storage media
(Cornell University, 2017) Hassan, Kilavo; Michael, Kisangiri; Mrutu, Salehe I.
Viterbi Algorithm Decoder Enhanced with Non-transmittable Codewords is one of the best decoding algorithm which effectively improves forward error correction performance. However Viterbi decoder enhanced with NTCs is not yet designed to work in storage media devices. Currently Reed Solomon (RS) Algorithm is almost the dominant algorithm used in correcting error in storage media. Conversely, recent studies show that there still exist low reliability of data in storage media while the demand for storage media increases drastically. This study proposes a design of the Soft Viterbi Algorithm decoder enhanced with Non-transmittable Codewords (SVAD-NTCs) to be used in storage media for error correction. Matlab simulation was used in this design in order to investigate behavior and effectiveness of SVAD-NTCs in correcting errors in data retrieving from storage media. Sample data of one million bits are randomly generated, Additive White Gaussian Noise (AWGN) was used as data distortion model and Binary Phase- Shift Keying (BPSK) was applied for simulation modulation. Results show that, behaviors of SVAD-NTC performance increase as you increase the NTCs, but beyond 6NTCs there is no significant change and SVAD-NTCs design drastically reduce the total residual error from 216,878 of Reed Solomon to 23,900.
Exploring a learning management system as a way to improve students’ understanding of geometry in secondary schools
(Taylor and Francis, 2021) Shaame, Abdalla A.; Anatory, Justinian R.; Osaki, Kalafunja M.; Mrutu, Salehe I.
The adoption of the learning management system (LMS) in secondary schools is scaling up around the globe. Many educational institutions use the LMS to mainstream teaching and learning. This study examined the effectiveness of the Moodle LMS in teaching and learning geometry in secondary schools. A quasi- experimental design was employed to generate data from two groups of students: the control group and the treatment group. The treatment groups learned geometry using the developed Moodle LMS while the control group learned geometry using the traditional chalk and talk method. Both the treatment and control groups did pre-test and post-test to track the impact of the intervention. The analysis of covariance (ANCOVA) test was employed to compare the pre-test and post-test scores and to make statistical analysis. The analysis revealed that the students who were taught geometry through the Moodle LMS outperformed those taught geometry through the traditional chalk and talk method. It is established in the study that for students to learn geometry better through the Moodle LMS, the system should be used to start teaching from the first topics of Form I to upper topics. Also, students should be given enough time to access the Moodle LMS to learn mathematics. The study concludes that the integration of the LMS in teaching and learning mathematics is a means by which failure in mathematics can be minimised.
Forward error correction for storage media: An overview
(Pittsburgh PA: IJCSIS Publication, 2015) Hassan, Kilavo; Michael, Kisangiri; Mrutu, Salehe I.
As the adoption of Information and Communication Technology (ICT) tools in production and service rendering sectors increases, the demand for digital data storage with large storage capacity also increases. Higher storage media systems reliability and fault tolerance are among the key factors that the existing systems sometimes fail to meet and therefore, resulting into data loss. Forward error correction is one of the techniques applied to reduce the impact of data loss problem in digital data storage. This paper presents a survey conducted in different digital data storage companies in Dar es Salam, Tanzania. Data were collected and analyzed using Statistical Package for Social Sciences (SPSS). Secondary data were captured from user and manufacturer technical reports. It was revealed that data loss is still a predominant challenge in the digital data storage industry. Therefore, the study proposes the new storage media FEC model using locked convolutional encoder with the enhanced NTCViterbi decoder.
Performance of binary locked convolutional codes with non-transmittable codewords in flat and slow rayleigh-fading channel
(Foundation of Computer Science, 2014) Mrutu, Salehe I.; Sam, Anael; Mvungi, Nerey H.
Communication over wireless media is vulnerable to distortion by noise. Therefore, the application of an error control mechanism is necessary to minimize the Bit Error Rate (BER). It is proposed to use locked binary convolutional code with Non-Transmittable codewords to enhance Viterbi Algorithm decoders; as one of the forward error correction mechanisms. The proposed enhancement empowers Viterbi algorithm decoders to reduce one of its inherent limitations of residual errors due to burst errors. This paper evaluates the performance of the locked (2, 1, 2) binary convolutional code with Non-Transmittable codewords enhancement technique over flat and slow Rayleigh Fading channel using a MATLAB software simulation. Simulation result shows 80.92 percent reduction of residual errors when 6 Non-Transmittable Codewords were applied to Viterbi Algorithm (VA) decoding. On the other hand, the technique lowers the encoder’s data transmission rate from 1/2 to 1/6.
Safety zone determination for wireless cellular tower - a case study from tanzania
(IJRET, 2013) Nyakyi, Christina P.; Mrutu, Salehe I.; Sam, Anael; Anatory, Justinian
Safety zone determination for wireless cellular towers has attracted attention from many researchers in the last decade. This is caused by the rapid growth of the wireless cellular industry which has led to the installation of towers even in the residential areas. There are many reports and ongoing researches regarding the biological and thermal effects of wireless cellular electromagnetic fields exposures to people. Cancer, hyperthermia, neural and behaviour effects of people exposed to these electromagnetic fields have been reported. This motivates the research to determine safety zones from wireless cellular towers to assure safety to those living in the vicinity of these towers. A model for safety zone determination is developed. The model takes the received power at the object, power transmitted by the transmitter and gain of the transmitter as inputs to determine the safe distance from the radiation of a wireless cellular transmitter. The power density received by the object and its geographical location from the radiation source are measured using the selective radiation meter. Transmitted power and the gain of the transmitter together with the height of the tower were obtained from the respective wireless cellular network operator. Based on the geographical location of the object, the distance from the radiation source was calculated using the haversine formula. These inputs are then used to determine the safety zone based on the standards and guidelines developed by WHO and ICNIRP.
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.
Trellis analysis of transmission burst errors in viterbi decoding
(IJCSIS PUBLICATION, 2014) Mrutu, Salehe I.; Sam, Anael; Mvungi, Nerey H.
The Viterbi decoder is the most favorable solution to the problem of decoding codewords from a convolutional encoder. Viterbi decoder performs exceptionally well when a received codewords block contains single or multiple and scattered errors in a received codewords block. However, the formation of burst errors in data transmission due to high transmission speed and the widely varying error conditions of wireless media in fading channel creates decoding challenge for such conditions which result in unbearable amount of residual errors. By using Viterbi decoders’ trellis diagrams, this paper analyses the effects of burst errors to the decoder that lead to residual errors and proposes improvement to the encoding and decoding procedures of the existing (2, 1, 2) binary convolutional encoder. The improved version facilitate effectiveness in the decoder (Viterbi algorithm) in decoding burst errors and hence reduction of residual errors in a poor channel. The proposed enhancements improve the decoder’s operational performance by 75 percent. However, the proposed modification reduces the encoder’s data transmission rate from 1/2 to 1/6.

Browsing by Author "Mrutu, Salehe I."

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