Papers by diana starovoytova
This study is a fraction of a larger-research on cheating in exams at the School of Engineering (... more This study is a fraction of a larger-research on cheating in exams at the School of Engineering (SOE). The study-design used a descriptive-survey-approach and a document-analysis. A designed confidential self-report-questioner was applied as the main-instrument for this-study, with the sample-size of 100-subjects, and a response-rate of 95%. The tool was pre-tested to ensure its validity and reliability. The study focused on the Attribution-Theory and the Pareto-principle. The data-collection-instrument was subjected to the statistical-analysis to determine its reliability via Cronbach's alpha-coefficient, and found high inter-item consistency (a > 0.9). The major-results of this-study revealed that 65% of respondents declared that cheating is, in fact, a common-phenomenon in the SOE; 60% of students also affirmed, that it is, actually, difficult to eradicate cheating in examinations in the SOE; and 70% of students acknowledged that they use mobile-phones to Google or to assess notes, during examinations. The results also illustrate that cheating, undeniably, is a very-real-issue of massive-concern at SOE; accordingly, several-recommendations to fight cheating were given and areas for further-research were identified as well. The findings of the study would potentially help in curriculum-development and delivery approaches, and for the improvement of the exciting or establishment of new academic-integrity-polices, which would, in turn, limit the growing-tendency by candidates, to seek shortcuts to good-grades, in their academic-endeavors.
Undoubtedly, plagiarism has been a global-concern, especially so, in institutions of higher-learn... more Undoubtedly, plagiarism has been a global-concern, especially so, in institutions of higher-learning. Furthermore, over the past-decades, cases of student-plagiarism, in higher-education, have increased, substantially. This-issue cannot be taken, without due-consideration, and it is crucial for educators, and universities, at large, to find the best-ways, to discourage and reduce the acts of students' plagiarism. The aim of this-study, therefore, was to address plagiarism in professional-university-education from undergraduate-engineering-students' attitudinal-perspective. In particular, to ascertain how plagiarism is defined by the students; which factors, they perceive, exacerbate plagiarism; how they justify plagiarism; and severity and penalty related to the misconduct. This-paper illustrates a fraction of a larger-research on plagiarism at the School of Engineering. The study-design used a descriptive-survey-approach and a document-analysis. A designed confidential self-report-questioner was applied as the main-instrument for this-study, with the sample-size (N=25), and a response-rate (RR=84%). The tool was pre-tested to ensure its validity and reliability. The data-collection-instrument was subjected to the statistical-analysis to determine its reliability via Cronbach's alpha-coefficient, and found high inter-item consistency (a > 0.9). The major-results of this-study revealed overall and widespread-deficiency in students' understanding of plagiarism; also more than half of the students, in the-subject-sample, were not adequately-informed about plagiarism in academic-writing; 76% of the respondents agreed, that those who say, they have never plagiarized, are lying; and also that everyone else around are plagiarizing (e.g., students, researchers, and academic-staff); 48% of the respondents agreed, that they keep on plagiarizing, because they have not been caught yet, while 33% stated, that they are tempted to plagiarize because, even if caught, the punishment (if any) will be light (the reward outweighs the risk). Several-specific-recommendations, on how to fight plagiarism, were provided, alongside with identification of areas for further-research. This-study would offer awareness to the undergraduates, lecturers, and the faculty-administrators, on the gravity of plagiarism-acts and how to avoid it, in the university. The study also will make a contribution (in its small-way) to the body of knowledge on the subject-matter.
This-study is a part of a larger-research on potential-environment-friendly-alternatives to polye... more This-study is a part of a larger-research on potential-environment-friendly-alternatives to polyethylene shopping-bags. At a general-level, the whole-research can be regarded as an explanatory-case-study of social-perception on plastic-menace-problem in Rift Valley Province, Kenya. The-survey was mainly aimed at understanding consumers' perceptions on plastic-bags, through consumption-habits, the degree of awareness of environmental-impacts and the willingness to reduce their-consumption. In order to most-accurately reflect the social-perceptions of the Kenyan-population, regarding single-use-plastic-bags consumption, a questionnaire was selected as the most-suitable-method, which was pre-tested to ensure its validity and reliability. A cross-stratification-technique was used, to determine the subject-sample-size of 384 respondents from three-towns, in total. Discrete-Choice-Experiment-technique, which originated from mathematical-psychology for investigating individual-preferences, was employed. The data-analysis was conducted using Epi-Info 7 (version 3.5.1), Minitab, and, Microsoft Excel, software. The Statistical-Package for Social-Sciences (SPPS-17, version 22)-computer software-program was used to compute the Cronbach's alpha coefficient. To check, whether there is an association between the variables, cross-tabulations was performed, while Chi-squared-test was used to test significance of the relationships. Cronbach's-alpha-test of internal-consistency was performed and demonstrated high inter-item-consistency (Cronbach's a > 0.9). The survey-results indicated that regardless of sex, educational-level, age-group and occupation, majority (80%) of the towns'-populace widely-used plastic-bags on a daily-basis in their-life-activities. Cheapness or free-distribution of these-bags, by retailers or supermarket-owners, are believed to be the main-reasons for the widespread-usage of polyethylene-single-use-shopping-bags, and, for the associated with their-disposal, problems. To combat these-problems, plastic Waste Management initiatives were highlighted, in conjunction with relevant-recommendations. The findings and recommendations of this-study will, expectantly, contribute (in its small-way) resolving the environmental-problems, associated with plastic-bags and their-disposal. This-research may also be valuable for Government-authorities, non-profit organizations, private-bodies or individuals, in order to develop adequate-and tailored-strategies and take actions, according to the actual-consumer-attitudes and perceptions.
Luffa cylindrica is an annual climbing plant whose fruit has a vascular network of fibres. These ... more Luffa cylindrica is an annual climbing plant whose fruit has a vascular network of fibres. These fibres are held together by pectins which degrade during water retting to release the fibres. In this paper, the extraction of luffa cylindrica fibres together with the combined effect of water retting and alkali treatment on its tensile properties are reported. The fibres were extracted from mature fruits of Luffa cylindrica through aerobic water retting process over a duration of 2 weeks, 4 weeks and 8 weeks. The extracted fibres were oven dried to a moisture content of 9.74±1.1% and tested in tension at gauge lengths of 10 mm. The fibres were characterized in terms of moisture regain, lignin content, hemicellulose content, and cellulose content. The combined effect of water retting and sodium hydroxide (NaOH) concentration on the fibre's breaking load, elongation, tenacity and linear density was also investigated. The luffa cylindrica fibres had a moisture regain of 10.81%, lignin content of 12.03%, cellulose content of 65.69%, and hemicellulose content of 19%. The linear density of the fibres retted for 2-8 weeks was 572–470 dTex .The determined breaking load of the fibres retted for 2-8 weeks was 1444.19-417.04 cN and 997.81-298.05 cN after treatments with 0%-16% NaOH. The fibre elongation was 4.0-24% after 2-8 weeks of retting and 4.3-14.5 % after treatments with 0%-16% NaOH. Tenacity of luffa cylindrica fibres was 6.0-25.25 cN/Tex after 2-8 weeks of retting and 5.9-20.22 cN/Tex after treatments with 0%-16% NaOH. From the study, an increase in aerobic water retting and concentration of NaOH had a positive effect on the tensile properties of the luffa cylindrica fibres.
Luffa cylindrica is an annual climbing plant whose fruit has a vascular network of fibres. These ... more Luffa cylindrica is an annual climbing plant whose fruit has a vascular network of fibres. These fibres are held together by pectins which degrade during water retting to release the fibres. In this paper, the extraction of luffa cylindrica fibres together with the combined effect of water retting and alkali treatment on its tensile properties are reported. The fibres were extracted from mature fruits of Luffa cylindrica through aerobic water retting process over a duration of 2 weeks, 4 weeks and 8 weeks. The extracted fibres were oven dried to a moisture content of 9.74±1.1% and tested in tension at gauge lengths of 10 mm. The fibres were characterized in terms of moisture regain, lignin content, hemicellulose content, and cellulose content. The combined effect of water retting and sodium hydroxide (NaOH) concentration on the fibre's breaking load, elongation, tenacity and linear density was also investigated. The luffa cylindrica fibres had a moisture regain of 10.81%, lignin content of 12.03%, cellulose content of 65.69%, and hemicellulose content of 19%. The linear density of the fibres retted for 2-8 weeks was 572–470 dTex .The determined breaking load of the fibres retted for 2-8 weeks was 1444.19-417.04 cN and 997.81-298.05 cN after treatments with 0%-16% NaOH. The fibre elongation was 4.0-24% after 2-8 weeks of retting and 4.3-14.5 % after treatments with 0%-16% NaOH. Tenacity of luffa cylindrica fibres was 6.0-25.25 cN/Tex after 2-8 weeks of retting and 5.9-20.22 cN/Tex after treatments with 0%-16% NaOH. From the study, an increase in aerobic water retting and concentration of NaOH had a positive effect on the tensile properties of the luffa cylindrica fibres.
The textile industry has been condemned as being one of the world’s worst offenders in terms of p... more The textile industry has been condemned as being one of the world’s worst offenders in terms of pollution. Chemical companies market a vast range of products such as dye formulations, colorants and finishing chemicals to the textile industry. This study was carried out in a textile mill. The research revealed that twenty two dyes and twenty five chemicals were used in the mill during twelve month period of the study. Thirty six Materials Safety Data Sheets (MSDSs) were collected from manufacturing companies/suppliers. Analysis of MSDSs together with the information provided on request by International Agency of Research on Cancer (IARC), France identified that various chemical substances used in the mill were harmful/toxic, carcinogenic, probably carcinogenic, and water polluting. Furthermore, it was identified that two out of three compounds classified as carcinogenic to humans were used in the mill either as chrome/metal/complex dye itself or as its mordants. It was therefore recommended to substitute chromium by hydrogen peroxide fixation. In addition, numerous problems with MSDSs and in occupational and safety practices on handling chemical substances in the mill were documented. The study consequently made several specific recommendations towards improvements.
This research was conducted within the Kenyan context in Embu prison on a pioneering and fully op... more This research was conducted within the Kenyan context in Embu prison on a pioneering and fully operational,
since 2011, biodigester system. After three years of operation it was imperative to assess the functionality of the
system and also the acceptance level by the users and beneficiaries. This research was significant as it
synthesizes the true-life experiences from Biodigester utilizing rare input-human excreta. The study was a crosssectional
descriptive research which sought to examine the operational practices and challenges of the
biodigester, alongside with factors influencing the adoption of biogas technology. To achieve this, the study
conducted regular field visits to Embu prison, administered interviews and distributed questionnaires (designed
in English and in Kiswahili language). The data was organized, edited, coded and analyzed using the Microsoft
Excel and Statistical Package for Social Sciences (SPSS). Response rate of detainees was 76%, while for staff it
was 43%. To address the issue of gas accumulation at night hours and fully utilize the potentials of human
excreta, the study proposed to incorporate microbial fuel cells (for electricity production). Conceptualization and
preliminary design of optimized system was conducted according to fundamental engineering design principles.
To select the best alternative design a pair-wise comparison known as the drop and re-vote (D&R) method was
used in this study. The study confirmed that biodigester in Embu prison is an appropriate solution to produce
clean renewable energy. Therefore it is recommended to pursue and replicate this approach in prisons in other
areas and in different public institutions of Kenya. The study also identified several directions for further
research; the most important one is to conduct detailed structural design of the proposed configuration including
economical evaluation of the system. The results and discussions may be also applicable to other countries or
regions with similar conditions.
Keywords: biogas, biodigester, human excreta, Kenya.
Abstract The residence time distribution (RTD) of mineral slurry and slurry holdup volume in an i... more Abstract The residence time distribution (RTD) of mineral slurry and slurry holdup volume in an industrial ball mill has been successfully studies using tracer tests. Six different conditions of solids concentration and three levels of ball loading were assessed. The effects of the slurry solids concentration and the ball loading on the mean residence time of slurry were clearly depicted in the results. Using the mass balance of salt tracer inside the mill, the slurry flow rate through the mill was estimated and the calculated values compared reasonably with the measured ones within the limits of experimental error. Further, based on the measured flow rates and residence times, it was possible to estimate the slurry holdup volume inside the mill. The correlation between slurry holdup volume with ball loading, slurry solids concentration and feed flow rate yielded plausible results. ANOVA statistical tests (F-test and t-test) were utilized to assess the adequacy of the correlation equation and the significance of the correlation coefficients. Keywords RTD, Holdup, Ball mill, Ball load, Slurry
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Papers by diana starovoytova
since 2011, biodigester system. After three years of operation it was imperative to assess the functionality of the
system and also the acceptance level by the users and beneficiaries. This research was significant as it
synthesizes the true-life experiences from Biodigester utilizing rare input-human excreta. The study was a crosssectional
descriptive research which sought to examine the operational practices and challenges of the
biodigester, alongside with factors influencing the adoption of biogas technology. To achieve this, the study
conducted regular field visits to Embu prison, administered interviews and distributed questionnaires (designed
in English and in Kiswahili language). The data was organized, edited, coded and analyzed using the Microsoft
Excel and Statistical Package for Social Sciences (SPSS). Response rate of detainees was 76%, while for staff it
was 43%. To address the issue of gas accumulation at night hours and fully utilize the potentials of human
excreta, the study proposed to incorporate microbial fuel cells (for electricity production). Conceptualization and
preliminary design of optimized system was conducted according to fundamental engineering design principles.
To select the best alternative design a pair-wise comparison known as the drop and re-vote (D&R) method was
used in this study. The study confirmed that biodigester in Embu prison is an appropriate solution to produce
clean renewable energy. Therefore it is recommended to pursue and replicate this approach in prisons in other
areas and in different public institutions of Kenya. The study also identified several directions for further
research; the most important one is to conduct detailed structural design of the proposed configuration including
economical evaluation of the system. The results and discussions may be also applicable to other countries or
regions with similar conditions.
Keywords: biogas, biodigester, human excreta, Kenya.
since 2011, biodigester system. After three years of operation it was imperative to assess the functionality of the
system and also the acceptance level by the users and beneficiaries. This research was significant as it
synthesizes the true-life experiences from Biodigester utilizing rare input-human excreta. The study was a crosssectional
descriptive research which sought to examine the operational practices and challenges of the
biodigester, alongside with factors influencing the adoption of biogas technology. To achieve this, the study
conducted regular field visits to Embu prison, administered interviews and distributed questionnaires (designed
in English and in Kiswahili language). The data was organized, edited, coded and analyzed using the Microsoft
Excel and Statistical Package for Social Sciences (SPSS). Response rate of detainees was 76%, while for staff it
was 43%. To address the issue of gas accumulation at night hours and fully utilize the potentials of human
excreta, the study proposed to incorporate microbial fuel cells (for electricity production). Conceptualization and
preliminary design of optimized system was conducted according to fundamental engineering design principles.
To select the best alternative design a pair-wise comparison known as the drop and re-vote (D&R) method was
used in this study. The study confirmed that biodigester in Embu prison is an appropriate solution to produce
clean renewable energy. Therefore it is recommended to pursue and replicate this approach in prisons in other
areas and in different public institutions of Kenya. The study also identified several directions for further
research; the most important one is to conduct detailed structural design of the proposed configuration including
economical evaluation of the system. The results and discussions may be also applicable to other countries or
regions with similar conditions.
Keywords: biogas, biodigester, human excreta, Kenya.