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Classification and clustering based methods for outlier detection of solar resource data

- Abrahams, Waldo

  • Authors: Abrahams, Waldo
  • Date: 2022-04
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/55423 , vital:51996
  • Description: Almost 90% of the primary global energy demand is serviced from the burning of fossil fuels (Abas, Kalair & Khan, 2015). Owing to the detrimental environmental impact of this, a global energy transition to the use of renewable energy, including solar energy, is needed (Gielen et al., 2019). An important aspect that inhibits the growth of solar energy is accurate solar resource data. Such data is needed because knowledge of the future reliability and quality of energy production is required to analyse a system’s performance and determine financial implications (Sengupta et al., 2017). Existing methods used to detect outliers in solar resource data do not efficiently identify outliers and an accurate and robust approach is required (Eastwood, 2019). Using simulated and real-world data, this study investigates the use of several classification methods, along with a two-stage clustering-classification approach to accurately identify outliers in solar resource data. The Treebag method proves to be an adequate outlier detection method for solar resource data. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2022
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  • Date Issued: 2022-04

The use of a rapid incineration field test for determining soil organic carbon in the Southern Cape Region

- Ackhurst, Albert Arthur

  • Authors: Ackhurst, Albert Arthur
  • Date: 2014-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/53336 , vital:45135
  • Description: Knowledge of soil organic carbon levels is important both for agricultural effectiveness and soil carbon sequestration accounting, especially against the backdrop of increased climate change impacts and pressure on food production landscapes. However, current methods for soil carbon determination are expensive, energy intensive, time consuming and potentially hazardous leading to a call for alternative methods, which should be cheap, fast, simple, accurate, safe and usable where resources and soil analysis laboratories are limited. To this end the student invented a novel rapid incineration field test (RIFT) for determining soil organic carbon and tested its validity in this study. This method incorporates principles found in dry combustion as well as loss-on-ignition and quantifying organic carbon through gravimetric analysis. In order to illustrate effectiveness and accuracy it was necessary to correlate RIFT with a reference method, in this instance dry combustion with a Leco device as well as another commonly used indirect method namely the Walkley-Black wet chemical oxidation method. Samples from eleven soil forms were collected from the Southern Cape region and they were subjected to the three testing methods. It was found that RIFT is indeed as effective and in 72% of the soil forms even more effective than Walkley-Black. Furthermore, it was ascertained whether the accuracy of RIFT can be improved by correcting for clay content. The correlation of RIFT with clay % was not very significant and clay % as a variable was therefore not used in this study to obtain further refinement of RIFT predictions. Another finding was also that RIFT illustrated less variability than both the Leco and Walkley-Black methods. Lastly it was ascertained that the RIFT device and methodology is indeed cost effective, energy efficient, fast and safe in terms of the need to use potentially hazardous chemicals. , Thesis (MA) -- Faculty of Science, School of Natural Resource Management, 2021
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  • Date Issued: 2014-12

Possible futures for the African built environment towards 2050

- Adendorff, Gillian Lorraine

  • Authors: Adendorff, Gillian Lorraine
  • Date: 2014-04
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's/Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/53325 , vital:45136
  • Description: Purpose –The purpose of this thesis is to develop four scenarios for Africa’s built environment over the nextfortyyears: The ”Angel” or “Good Governance”Scenario,in which positive elements become a realisation for Africa’s built environment and are conjointly favourable; The “Dwarf” or “Uneven African Development”Scenario, in which key driving forces unfold inan uneven pattern, or have a differentiated impact on Africa’s built environment; The “Elf” or Bad Governance Scenario,in which less good governance prevails, but where a fortunate built environment and securemanagement allowsAfrica to become competitive and benefit from satisfactory economic growth;and The “Hobgoblin” or “Business and Governance as usual” Scenario,in which negative regional drivers of change corrode positive policies and initiatives in a manner which compounds the pre-existing threats of Africa’s built environment development.Design/Methodology/Approach –The goal of this thesis is not only to affirm what is already known and knowable regardingwhat is happening right now at the intersections of Africa and its built environment development, but also to explore the many ways in which environmental scanning and built environment development could co-involve,both push and inhibit each other,in the future. Thereafter, this thesis beginsto examine what possible paths may be implicatedfor Africa’s poor and vulnerable built environment. Scenario planning is a methodology designed to help researchers, organisations and even nations alike through this creative process. This thesis begins to identifydriversof change, and then combines these driversin different ways to create a set of scenarios regardinghow the future built environment of Africa could evolve.Practical implications –This thesis provides a useful insight regardingdrivers for change for Africa’s built environment,and how to anticipate these changes in the mostcurrentScenario planning.Originality/Value –This thesis addressesthe future of Africa’s built environment from a decision maker’s point of view over the next 40 years. , Thesis (PhD) -- Faculty of Engineering, the Built Environment and Technology, School of the Built Environment and Civil Engineering, 2021
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  • Date Issued: 2014-04

Itileni

- Amakwenkwe men (Performer), Composer not specified

  • Authors: Amakwenkwe men (Performer) , Composer not specified
  • Subjects: Vocal , Walking song , Nontshinga Location , Kentani District , Transkei , Eastern Cape Province , South Africa
  • Type: Sound , Music
  • Identifier: vital:15243 , MOA18-03 , http://hdl.handle.net/10962/d1017402 , MOA18
  • Description: English translation of title: 'The train' , Sung by a group of young men on their way to a dance; they are singing that they can look down on the train that goes from Mazeppa to Natal , This recording is held at the International Library of African Music. For further information contact ilamlibrary@ru.ac.za , This recording was digitised by the International Library of African Music , Original format: 15ips reel , Equipment used in digitisation: Studer B 67 Tape Recorder; Nagra III , Software: Sound Forge V.6 , Sample rate: 44100Hz 16Bit Stereo
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Malilela imango ingasiyo yabo

- Annie Macholweni (Performer), Composer unknown

Contour plan of Grahamstown

- AWM, Hodge, WA

  • Authors: AWM , Hodge, WA
  • Date: 1934
  • Subjects: Grahamstown (South Africa) -- Maps Maps , South Africa
  • Language: English
  • Type: cartographic , map
  • Identifier: http://hdl.handle.net/10962/68301 , vital:29236 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa MP407 , MP407
  • Description: Contour plan of Grahamstown, 1934. Drawn by A.W.M. ; signed by W.A. Hodge, City Engineer. "War time regulations: this plan must not be removed from college premises under any circumstances" signed by E H Wied.
  • Full Text: false
  • Date Issued: 1934

Plan of the subdivisions of Featherstone's Kloof originally called Kowiefontein showing the portion it is proposed to sell

- AWM, Hodge, WA

Ndhlamini

- Baca men (Performer), Composer not specified

The Isicathulo Gum-boot dance

- Baca men (Performer), Composer not specified

Wanga muthanga hadini

- Balanyalani Muzanani and friends (Performer), Composer not specified

Bidera

- Baranganani Mudzanani (Performer), Composer not specified

  • Authors: Baranganani Mudzanani (Performer) , Composer not specified
  • Subjects: Self delectative , Indigenous folk music , Mbira , Nsako , Johannesburg , Transvaal (Gauteng) , South Africa
  • Type: Sound , Music
  • Identifier: vital:15389 , MOA28-13 , http://hdl.handle.net/10962/d1017695 , MOA28
  • Description: Self delectative song by Baranganani Mudzanani, with mbira (24 reeds, 2 manuals, board resonator) , This recording is held at the International Library of African Music. For further information contact ilamlibrary@ru.ac.za , This recording was digitised by the International Library of African Music , Original format: 15ips reel , Equipment used in digitisation: Studer B 67 Tape Recorder; Nagra III , Software: Sound Forge V.6 , Sample rate: 44100Hz 16Bit Stereo
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Self-concept as a measure of success in the military environment

- Besener, Paul Robert

  • Authors: Besener, Paul Robert
  • Date: 1987
  • Subjects: Self-perception , Control , Recruits , Soldiers , Military , National service , South Africa , Pupils , Learners , Guidance , School curriculum
  • Language: English
  • Type: text , Thesis , Masters , MEd
  • Identifier: vital:1363 , http://hdl.handle.net/10962/d1001429
  • Description: This piece of research is an attempt to evaluate the relationship between military 'success' and the psychological preparedness of recruits in terms of their self-concepts and locus of control orientations. The new recruit is forced to adapt to the military environment which will, in turn, attempt to change him into an effective soldier. It was noticed by the researcher, who was involved in military training at the time, that a number of recruits, even some with seemingly limited potential, coped well, while others who seemed to have the ability failed to cope adequately. Recruits completed questionnaires which provided the researcher with biographical data and background information. In addition, the Bledsoe Self-Concept Scale and the Nowicki and Strickland Locus of Control Scale were used in order to determine their self-concepts and locus of control orientations respectively, prior to the beginning of national service. Detailed unstructured interviews were also conducted with a sample of military personnel, to provide another basis for gathering data and for clarifying some of the issues involved. Briefly, the chief conclusion of this researcher is that a significant majority of 'successful' recruits in the military environment have a positive self-concept and an internal locus of control. On the basis of the above finding, it is suggested that there is a need to guide pupils about certain aspects of military life before they begin their National Service. There would seem to be a need for this guidance to be incorporated into the school curriculum, together with such practical aspects as cadets, shooting, etc. There is a shortage of this kind of research on the military situation in South Africa, and it is suggested that numerous issues in this field need to be researched for the benefit of future conscripts and the military alike.
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  • Date Issued: 1987

An investigation into the effects of nano-carbons on the negative electrode morphology of lead acid batteries under high rate partial state of capacity cycling

- Bolo, Lukanyo

  • Authors: Bolo, Lukanyo
  • Date: 2021-04
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/53324 , vital:45132
  • Description: New technological developments in the field of Hybrid Electric Vehicles (HEV’s), vehicle stop-start applications and electrical power utility devices have brought about new demands on the use of energy storage devices such as the Pb-acid battery. These applications require a new understanding and research into the material chemistry of the battery where it has to functionin a Partial State of Capacity Cycling (PSoCC) or High Rate Partial State of Capacity Cycling (HRPSoCC)duty. The Pb-acid battery is well known for its use in the automotive industry where it had worked for decades as a typical Starter, Lighting and Ignition (SLI) power source. However, the conventional Pb-acid battery is not suitable for the new types of vehicle demands and applications. When the Pb-lead acid battery is subjected to PSoCC conditions, very quickly excessive amount of non-conducting PbSO4crystals are formed on the negative plates of the battery that then drastically reduce its useful life in application. Over the years, researchers have shown that the small addition of certain carbon types to the negative plate active material (NAM) during battery manufacturing can reduce the sulfation effect thereby increasing its use the modern vehicle applications. This study investigated industrial manufactured cells that contained up to 0.5 % by weight two types of carbons in the NAM. These were compared to standard built cells in terms of their standard achievable capacities at various rates, their Cold Cranking Ability (CCA), their Dynamic Charge Acceptance (DCA) and a simplified PSoCC test. The carbons were classified as an activated carbon and a carbon nano-fiber and were included as a dry weight additive during the standard paste manufacturing process of the negative plate. Cells were built with a 9-plate configuration using standard expanded grid positive plates with a nominal rated capacity of 36 Ah. The cells were formed and subjected to a number of electrochemical tests, of which selected negative plates were then studied using Scanning Electron Microscopy (SEM) and Electrochemical in-situ Atomic Force Microscopy (EC-AFM). The microscopic study was then used to try and relate the observed material characteristics of the NAM with the carbons to the electrochemical results observed when testing a built cell. , Thesis (MA) --Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
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  • Date Issued: 2021-04

Bomme ba Sithisi

- Botha, Karika (Recorded by ), Sesotho boys and girls (Performer), Composer unknown

Ke naleni Modisa

- Botha, Karika (Recorded by), Sesotho creche child (Performer), Composer unknown

Se me tsere tsere senatla

- Botha, Karika (Recorded by), Sesotho children (Performer), Composer unknown

Paisekele

- Botha, Karika (Recorded by), Sesotho children (Performer), Composer unknown

Joni

- Botha, Karika (Recorded by), Sesotho children (Performer), Composer unknown

Fikara tsa makoti

- Botha, Karika (Recorded by), Sesotho women (Performer), Composer unknown

Jeso rato la gago

- Botha, Karika (Recorded by), Sesotho children (Performer), Composer not specified

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