Browsing by Author "Charles, George"

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    An investigation of sexual abuse among o-level secondary school students in Tanzania and its effects on students’ academic development:a case of Ilala municipality
    (University of Dar es Salaam, 2015) Charles, George
    The purpose of this study was to investigate sexual abuse existing on the O-Level secondary school students aged between 14-17 years in Tanzania. The specific objectives were to identify the knowledge students have about various forms and causes of sexual abuse ; to analyse the methods used to lure students into sexual activities; to identify the effects of sexual abuse on students’ behaviour and academic development; and to analyse measures being taken to curb sexual abuse of secondary school students.The study employed mixed research approach with descriptive survey design. The data were collected through a questionnaire and interview. The study was carried out in ten secondary schools from five wards in Ilala Municipality. Stratified simple random sampling and purposive sampling techniques were used to obtain the study sample. Quantitative data were analysed through descriptive statistics. Content analysis was used to analyse qualitative data.The findings indicate that all the students were aware and had adequate knowledge of sexual abuse. The study revealed that 33.9% of students had experienced sexual abuses in one form or another. Most perpetrators were relatives, strangers, friends, school watchmen and step parents. The incidents mostly occurred at homes, beaches, and on the way back home from school. The study concludes that sexual abuse among secondary school students mostly exists and occurs in familiar settings by familiar people. Serious measures need to be taken to curb the problem. Otherwise, most of secondary school students will continue to be victimized
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    Throughput Improvement of Selective Repeat plus Go-Back-N ARQ Scheme Using FEC and Diversity in fading channels
    (University of Dar es Salaam, 2016) Charles, George
    Wireless communication is the fastest growing segment in the communication industry. The integration of real time applications has accelerated the segment toward demanding more throughput efficiency in error prone fading radio channels Automatic Repeat Request (ARQ) is one among strategies of error control schemes used to mitigate the effect of finding, but the related throughput efficiencies drop drastically when Bit Error Rate(BER) increases above 10-3. Therefore, there is need to minimize the probability of receiving errors by increasing the Signal to Noise Ration at the receiving and or correct the received errors. This dissertation improved the throughput efficiency of the SR+GBN scheme without FEC and that which include FEC using diversity combining. Previous researchers improved the throughput of the scheme using FEC or diversity combining only. This dissertation derived a new throughput efficiency equation for the scheme to include FEC and diversity combining scheme for the purpose of improving the SNR at the receiver and hence improve BER and throughput efficiency of SR+GBN scheme. At the BER of 10-2 and above, the throughput efficiency of the scheme conventional SR+GBN without FEC was 0 and did not rise above 0.5 at BER of 10-1 even when the BCH code of up to 10 error correction bit capability was used. With this new technique to the scheme, when 3 antennae MRC combiner was used at a point with 10Db, the BER decreased from 10-2 to 10-4 and the throughput efficiency increased from 0 to nearly 1.