Natural Sciences

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    Copying strategies to chronic floods in Kuku residential area in Lusaka district, Zambia: a hermeneutic phenomenology study.
    (The University of Zambia, 2023) Bulambo, Catherine Whitness
    Chronic flooding is one major annual disaster, whose effects have not been sparing the residents in Kuku, a low cost residential area in the urban District of Lusaka. It has been attributed by both natural and manmade factors such as the inability of the residential area to drain water, change of rainfall pattern, increase of built environment without sustainable drainages and poor garbage disposal with emphasis on the non-biodegradable materials. Incidentally, this study entails the captured raw lived experiences of chronic flood victims of the Kuku residential area of Lusaka district from a hermeneutic phenomenology approach study. It was entirely anchored from a qualitative methodology. Descriptive, Hermeneutic phenomenology and explorative research designs, snowball sampling method, unstructured interview guide, observation and a camera were used to generate data from the participants. With the use of a thematic analysis, the study exposed the effects of the flooding which are; victims are sometimes left homeless, affected with waterborne diseases, loss or disruption of welfare, loss of diversity of livelihoods and trauma. It also considered a magnitude of lived experiences from flood victims with three or more annual episodes of floods. The captured experiences and challenges among flood victims included; sleepless nights and fear to relocate, social conflicts, fear of junkies and negative effects of flooded potholes and dug trenches. Despite the severe effects of urban flooding, most resilient flood victims in Kuku have continued to inhabit the area due to the opportunities and limited options available to them and their socioeconomic status. The study reported that flood victims had over time developed copying strategies which help to adapt to conditions of the residential area. These include; the use of sandbags and pouring of sand to elevate the low lying Earth surface areas, dig trenches, build houses and toilets with a high elevation to prevent flood water from flowing through them. Some victims are left traumatized during and after the flooding. To this effect, most flood victims were against permanent relocation. The failure to refurbish dilapidated houses and lack of a reliable source of sustainable financial support system to help them relocate and live in nonprone area expedites the challenges experienced with flooding. Findings indicate that, overall, the raw lived experiences of the chronic flood victims are a reflection of their resilience, vulnerability of the urban low cost residential area to flooding ,the capability of their socioeconomic status to sustain themselves and poor planning of the built environment. The study also recommends that the victims and all kuku residents should holistically implement the following eco-friendly sustainable measures in order to reduce the effects of flooding; personal hygiene, construction of a recycling centre for non biodegradable domestic garbage within Kuku residential area, mobile dumpster, construction of an organic manure centre, environmental education to be embraced by the residents, inclusive area improvement and sensitization programs to be put in motion, provision of garbage collection services by the local authority, engaging proper engineers, increasing drainage systems and advocating and implementing the construction of flushable toilets with septic tanks.
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    The management of examination malpractice using blockchain technology.
    (The University of Zambia, 2023) Sikuyuba, Mweemba
    The issue of post-examination malpractice is a significant concern in the educational sector, and it is good to see that efforts are being made to address this problem. Your proposed solution to use blockchain technology to prevent grade manipulation is an innovative approach that could have a positive impact on the integrity of the examination process. The respondents using questionnaires used the purposive sampling technique. Based on the conducted statistical analysis of the data collected from the respondents, who include, among others, IT administrators, software developers, data entry officers and selected chief markers to determine the effectiveness of the proposed model. The inferential part of the analysis, which dealt with hypothesis values for the P-value and the sample t-test, is also a common statistical method used to test the significance of the results. The result obtained through effort expectancy, t(91)=.031, p=.976 with a 95% level of significance, suggests that the null hypothesis was rejected, and an alternative accepted means that effort expectancy influenced the adoption of blockchain technology. The use of the SHA-256 hashing technique is a standard method of ensuring the integrity and authenticity of digital documents, and it can be used to create a unique digital signature for each document that is added to the blockchain. Overall, the proposed solution shows the potential of technology-based solutions to address issues related to the integrity of the examination process. Further research and testing are needed to determine the feasibility and effectiveness of the proposed solution in practice.
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    Comparative study on rate of convergence to normal distribution for u-statistics and method of moments estimator for population variance.
    (The University of Zambia, 2019) Hambulo, Jimmy
    In this dissertation, we examine the small and large sample properties of the U-statistics (Un) for an estimable parameter : For small sample, Un is found to be MVUE and Su cient. Large sample properties of Un examined are Consistency and Asymptotic normality. We also compare the rate of convergence to normal distribution between the U-statistics and the method of moments estimator for the population variance. Berry-Esseen bound for U- statistics of order 2 is given and the results are used to nd the rate of convergence to normal for the U-statistics for the population variance. Berry-Esseen bound for S2 the method of moments estimator for the population variance is also given. Method of moments estimator is found to converge faster to normality than the U-statistics. Finally, we review the di erent proofs of Hoe ding's one sample U-statistics theorem as given in the period 1948-2012.
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    Outdoor testing of some commercial solar panels found on the Zambian market in terms of their fill-factor and efficiency.
    (The University of Zambia, 2023) Chiyesu, Simeon
    The power utility company in Zambia, the Zambia Electricity Supply Corporation (ZESCO) introduced load-shedding in urban and rural areas in 2015 when the country experienced severe drought and caused low water levels in our hydropower stations for power generation and distribution. To mitigate load-shedding the Government of the Republic of Zambia (GRZ) encouraged citizens to consider using solar energy for lighting, TV or radio operations or water heating and run small businesses such as saloons and barber shops using solar power. Most solar solutions are in the form of photovoltaic (PV) systems, solar heaters and solar geysers. Solar panels, for example, have output ratings displayed on their back side. These values give the solar panel output power specifications and the quality of the solar panels. However, there has been no technical report (from the author) on the data provided by different solar panel manufacturers and the locally tested data as a validation of the quality of solar panels on the Zambian market. It is a known fact that solar panels are tested under standard test conditions such as solar irradiance of 1000 W/m2, temperature of 25℃, and air mass of AM 1.5 different from out-door environmental conditions. The aim of this research is to validate the quality of solar panels available on the Zambian market by comparing the manufacturer’s claims with outdoor tested parameters based on local conditions. The study will collect data on the types and sizes of solar panels supplied in Zambia and test each category of power ratings, fill factor and efficiency. The study will use the I-V curve tracer to determine I-V characteristics and a Solar Survey Meter 200R instrument to obtain solar irradiance, panel tilt and panel temperature. The findings showed that there are substandard solar panels on the Zambian market with an average power output drop as high as 45%, much higher than the recommended power drop of 16.5%. One of the major reasons for this power drop is the degradation of the cells and hence an increase in series resistance of the panels arising from an increase in temperature of the solar cells and thermo-mechanical fatigue of the solder bonds and interconnections. Based on the above findings, the study recommends regulatory measures for manufacturers and suppliers as well as education and assistance for citizens on the usage, maintenance and choice of solar photovoltaic systems.
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    Development of identity attribute metrics model based on distance metrics.
    (The University of Zambia, 2020) Kabwe, Felix Musama Lameck
    The growth in the use of online services on the World Wide Web has proliferated into cyber mischief, personality or object misrepresentation, and cybercrime. Diverse entities of different interests and intentions form a wide range of complex online identities and beneficiaries of the online activities. Fraudsters and criminals hide their online identities to steal services, assets and other valuables or harm innocent internet users. This research would help in strengthening of identity management systems as a way to arrest this growing problem and guarantee secure online services and online interactions. This research desires to identify a mathematical model that would help in improving cyber security in digital identity management. This work intends to develop metrics models based on distance metrics in order to quantify the credential identity attributes used in online services and activities. This study adds knowledge to past work on the subject matter to provide quantitative analysis to quantify the credential identity attributes in online services. The study considers major sources of identity attributes currently being used in the application and registration forms for the various services offered both in cyber and real space. The study further explores the extraction of key identity attributes that were extracted from identity tokens like identity documents, application and registration forms for the various services offered both in the cyber and real space. At the core of the research, the study seeks to establish how we would develop the identity attribute metrics model which could be used to quantify the identity attributes based on distance metrics mathematical models. The study utilized survey research with closed-ended researcher administered questionnaire. A total of 160 questionnaires were administered with a response rate of 93%. The primary data obtained from questionnaires was analysed using Statistical Package for Social Science (SPSS) and Excel. The respondents were drawn from Banks (14%), Churches (12%), Government of the Republic of Zambia (6%), Hospitals (16%), Insurance (10.7%), Mobile Phone companies (2%), and less than 1% from Pensions. Others were Schools (21%), Universities (16%), and Utility companies (1.3%). The techniques that have been used include data mining techniques and statistical analysis. The perception constructs in the research included Usefulness, Trust, Ease of use, Image, and User satisfaction. It was observed that some attributes were more important than the others in identifying entities. Statistical analysis revealed that among the constructs that were used, Usefulness, Trust and Ease of use were strongly related. Tools to text mine the identity attributes helped to generate statistical data to come up with a quantitative model metrics to assist in the identification of an online entity. Using a detailed literature review, questionnaire surveys in this area, text mining of the identity attribute from the application forms, and the results of the study helped to develop the identity attribute metrics model. An identity attribute metrics model based on distance similarity has been proposed. The Distance similarity is based on Cosine Similarity measure. Based on this study, digital identity management in online services and activities should adopt the developed Cosine Similarity measure, the identity attribute metrics model based on distance metrics, to strengthen online identity management. This will help to curb online fraud, identity theft, and other cybercrimes. This model could be augmented to past efforts to come up with a multimodal solution and add value to the resolution of the said problem.