This research effort develops a comprehensive computational framework to support the parametric optimal design of uncertain dynamical systems. Uncertainty comes from various sources, such as: system parameters, initial conditions, sensor and actuator noise, and external forcing. Treatment of uncertainty in design is of paramount practical importance because all real-life systems are affected by it; not accounting for uncertainty may result in poor robustness, sub-optimal performance and higher manufacturing costs. Contemporary methods for the quantification of uncertainty in dynamical systems are computationally intensive which, so far, have made a robust design optimization methodology prohibitive. Some existing algorithms address uncertainty in sensors and actuators during an optimal design; however, a comprehensive design framework that can treat all kinds of uncertainty with diverse distribution characteristics in a unified way is currently unavailable. The computational framework uses Generalized Polynomial Chaos methodology to quantify the effects of various sources of uncertainty found in dynamical systems; a Least-Squares Collocation Method is used to solve the corresponding uncertain differential equations. This technique is significantly faster computationally than traditional sampling methods and makes the construction of a parametric optimal design framework for uncertain systems feasible. The novel framework allows to directly treat uncertainty in the parametric optimal design process. Specifically, the following design problems are addressed: motion planning of fully-actuated and under-actuated systems; multi-objective robust design optimization; and optimal uncertainty apportionment concurrently with robust design optimization. The framework advances the state-of-the-art and enables engineers to produce more robust and optimally performing designs at an optimal manufacturing cost. / Ph. D.

二次世界大戰時，美國擊敗日本，使朝鮮半島脫離殖民統治，然而隨後的美蘇冷戰，使得朝鮮半島分裂成南北兩韓，而美國與南韓簽訂條約，成立美韓同盟(U.S.–South Korea Alliance)，成為繼日本之後，美國在亞洲的另一個戰略同盟。冷戰與後冷戰期間，美韓關係雖有波折，但不影響美韓同盟的強度。直到2000年美國小布希就任，其強硬的北韓政策與南韓金大中的陽光政策形成對比，成了美韓關係不協調的開端。而後連任的小布希延續其北韓政策，南韓繼任的盧武鉉將陽光政策擴大實施，推出和平繁榮政策，美韓兩國的北韓政策再度不同調，兩國關係持續跌宕起伏至2008年。本研究試圖以攻勢現實主義分析美國此時期的北韓政策；以新自由制度主義檢視南韓的交往政策，透過理論交鋒研究兩國利益的差異，並檢視外部因素如中國、日本、俄羅斯的影響，進而解釋此時期美韓關係不協調的原因。 / In 1945, the U.S. defeated Japan. The Korean peninsula was liberated from Japanese colonization at the end of World War II. However, the confrontation between the U.S. and the Soviet Union left two Koreas separated by the Demilitarized Zone from the Cold War to the present. In addition, based on the Mutual Defense Treaty Between the United States of America and the Republic of Korea, the U.S.–South Korea Alliance was established. During the Cold War and Post Cold War era, the U.S.-South Korea relations faced hard times, but the alliance remained strong. When George W. Bush became the president of the U.S. in the year 2000, his hardline policy toward North Korea collided with South Korea’s Sunshine Policy, which was made by the president Kim Dae-jung. These different policies toward the North caused tensions to the U.S.-South Korea relations. Then the re-elected Bush continued hardline policy against North Korea, but South Korea’s new president—Roh Moo-hyun—decided to inherit the sunshine policy and develop Peace and Prosperity Policy. Washington and Seoul still failed to reach a consensus on how to deal with Pyongyang. The U.S.-South Korea relations continued to fluctuate until 2008. This study tries to analyze the U.S. policy toward North Korea through offensive realism and examine South Korean engagement policy through neoliberal institutionalism from 2000 to 2008. Besides, this thesis also considers exogenous factors such as China, Japan, and Russia, trying to explain the inconstancy of the U.S.-South Korea relations.

Text in English with abstracts in English, Sepedi and Venda / Access to firewood and other affordable energy sources is essential to the livelihoods of rural households in developing countries. Studies have been conducted to understand the reasons behind an extensive reliance on firewood in rural areas, especially in developing countries, despite improved electrification rates and a number of government policies introduced to encourage rural households to switch from traditional to modern fuels. This study aimed at assessing and thus understand the factors influencing the use of firewood by households in Ga - Malahlela village in Limpopo Province. Limited research has been conducted on firewood use, subsequent to improved electrification in rural areas in South Africa, hence it was to shed light on this little-explored subject on which the study was carried out. The assessment was based on household demographics and household energy use patterns, with a structured questionnaire being utilised to arrive at a detailed understanding of the factors that drive firewood use. It was established that firewood was still used to a significant degree, to satisfy household energy needs such as cooking, water heating and space heating. This was mainly due to the socioeconomic status of households. Socio-economic factors such as income, education level, household size and preference were found to be the factors exerting the greatest influence on the use of firewood among households in the study area. Psychological variables and the geographical location of the study area were also shown to promote the use of firewood. The study further revealed that, as indicated in the reviewed literature, households in the study area fuel stack and do not ascend the energy ladder. The reviewed literature further indicated that not all factors have equivalent significance in determining the behaviour and pattern of household energy use. This indicates that energy sources such as firewood are not completely discarded but are instead used in conjunction with modern energy sources such as electricity. In conclusion, this study established that despite the availability of electricity, as a result of poverty and the lack of free basic services such as free basic electricity, reliance on firewood in rural areas will continue. / Go hwetša dikgong le methopo ye mengwe ya dibešwa tšeo di rekegago go bohlokwa go mekgwa ya malapa a dinagamagaeng go hwetša dilo tše bohlokwa tša bophelo dinageng tšeo di hlabologago. Dithutelo di phethagaditšwe go kwešiša mabaka ao a thekgago kholofelo go dikgong mafelong a dinagamagaeng a dinaga tšeo di hlabologago le ge go na le ditekanyo tše di kaonafaditšwego tša tlhagišo ya mohlagase le palo ya melaotshepetšo ya mmušo yeo e tsebišitšwego go tutuetša malapa a dinagamagaeng go fetoga go tloga go dibešwa tša sekgale go iša go tša sebjale. Thutelo ye e ikemišeditše go lekola ka gona go kwešiša mabaka ao a huetšago malapa a Motsaneng wa Ga-Malahlela ka Profenseng ya Limpopo go diriša ya dikgong. Dinyakišišo tše lekantšwego di phethagaditšwe ka ga tirišo ya dikgong ka morago ga tlhagišo ya mohlagase yeo e kaonafaditšwego mafelong a dinagamagaeng ka Afrika Borwa, gomme e be e swanetše go fa tshedimošo ka ga hlogotaba yeo e hlohlomišitšwego gannyane gore thutelo ye e phethagatšwe. Tekolo ye e theilwe go dipalopalo ka ga malapa setšhabeng le mekgwa ya malapa ya go dirišwa dibešwa, ka go diriša lenaneopotšišo leo le beakantšwego gore go fihlelelwe kwešišo ye e hlalošago ka botlalo mabaka ao a hlohleletšago tirišo ya dikgong. Go lemogilwe gore dikgong di sa dirišwa ka bontši bjo bo bonagalago go kgotsofatša dinyakwa tša malapa tša enetši tše bjalo ka go apea, go ruthetša meetse le go ruthetša lefelo. Se se be se swanela gagolo ka lebaka la boemo bja ka moo ekonomi e amago tšwelopele ya malapa. Mabaka a ka moo ekonomi e amago tšwelopele ya setšhaba a go swana le ditseno, boemo bja thuto, bogolo bja lelapa le tšeo di ratwago go hweditšwe go ba mabaka ao a hlohleletšago khuetšo ye kgolokgolo go tirišo ya dikgong gare ga malapa thutelong ye. Dielemente tšeo di ka fetolwago le lefelo tikologong ye e itšeng tša thutelo le tšona di bontšhitšwe go godiša tirišo ya dikgong. Thutelo ye gape e utollotše gore, bjalo k age go šupilwe dingwalong tšeo di lekotšwego, malapa a lefelong la thutelo a latela mekgwa ya dibešwa tša mehutahuta gomme ga a latele manamelo a enetši. Dingwalo tšeo di lekotšwego di laeditše go ya pele gore ga se mabaka ka moka ao a nago le bohlokwa bjo bo lekanago go šupeng boitshwaro le mokgwa tša tirišo ya enetši ka malapeng. Se se šupa gore methopo ya enetši ye bjalo ka dikgong ga se ya tlogelwa ka gohlegohle eupša e dirišwa mmogo le methopo ya sebjale ya enetši ye bjalo ka mohlagase. Go ruma, thutelo ye e utollotše gore le ge go na le mohlagase, ka lebaka la bohloki le tlhaelo ya ditirelo tša motheo tša mahala tše bjalo ka mohlagase wa motheo wa mahala, kholofelo go dikgong dinagamagaeng e tlo tšwela pele. / U swikelela khuni na zwiṅwe zwiko zwa fulufulu zwine zwa swikelelea ndi zwa ndeme kha u tsireledza zwo teaho zwa vhutshilo kha miṱa ya vhupo ha mahayani kha mashango o no khou bvelelaho. Ngudo dzo farwa u itela u pfesesa zwiitisi zwa u ḓitika zwihulwane nga khuni kha vhupo ha mahayani kha mashango ane a khou ḓi bvelela zwi si na ndavha na u khwiniswa ha u dzheniswa ha muḓagasi na tshivhalo tsha mbekanyamaitele dza muvhuso dzo ḓivhadzwaho u ṱuṱuwedza miṱa ya vhupo ha mahayani u bva kha u shumisa zwivhaswa zwa kale u ya kha zwa ano maḓuvha. Ngudo iyi yo livhiswa kha u asesa na u pfesesa zwiṱaluli zwine zwa ṱuṱuwedza u shumiswa ha khuni nga miṱa ya Muvhunduni wa Ga-Malahlela Vunduni ḽa Limpopo. Ṱhoḓisiso dzi si nngana dzo itwa nga ha u shumiswa ha khuni hu tshi tevhela u dzheniswa ha muḓagasi vhuponi ha mahayani Afurika Tshipembe, ho vha u bvisela khagala nga ha zwiṱuku zwo wanululwaho kha thero heyi ye ngudo ya i bveledzisa. U linga ho vha ho ḓisendeka nga ngudamirafho ya miṱa na kushumisele kwa fulufulu miṱani, hu na mbudzisombekanywa dzo dzudzanywaho dzo shumiswaho u swikelela kha u pfesesa nga vhuḓalo zwiṱaluli zwine zwa ta u shumiswa ha khuni. Ho dzhielwa nṱha uri khuni dzi kha ḓi shumiswa nga maanḓa u ḓisa ṱhoḓea dza fulufulu miṱani u fana na u bika, u vhilisa maḓi na u dudedza vhudzulo. Hezwi zwo tea nga maanḓa kha vhuimo ha matshilisano a zwa ikonomi miṱani: zwiṱaluli zwa ikonomi ya matshilisano zwi ngaho sa mbuelo, vhuimo ha pfunzo, vhuhulu ha muṱa na zwo no takalelwa ho wanwa uri ndi zwiṱaluli zwine zwa shumisa ṱhuṱhuwedzo khulwane ya u shumiswa ha khuni vhukati ha miṱa ya vhupo ha ngudo. Variabuḽu dza saikhoḽodzhikhaḽa na vhupo ha ḓivhashango zwa vhupo ha ngudo zwo sumbedziswa u ṱuṱuwedza u shumiswa ha khuni. Ngudo yo isa phanḓa na u wanulusa uri, sa zwo sumbedziswaho kha maṅwalwa o sedzuluswaho, miṱa kha vhupo ha ngudo i kuvhanganya fulufulu ngeno hu sina u gonya ha tshanduko ya kushumisele kwa fulufulu. Maṅwalwa o sedzuluswaho o sumbedzisa a tshi i sa phanḓa uri a si zwiṱaluli zwoṱhe zwine zwa vha na ndeme i linganaho kha u ta vhuḓifari na kushumisele kwa fulufulu miṱani. Hezwi zwi sumbedza uri zwiko zwa fulufulu zwi ngaho sa khuni a zwo ngo laṱelwa kule tshoṱhe fhedzi zwi shumiswa zwo ṱanganyiswa na zwiko zwa fulufulu zwa ano maḓuvha zwi ngaho sa muḓagasi. Ri tshi pendela, ngudo iyi i ta uri na musi muḓagasi u hone, nga nṱhani ha vhushayi na ṱhahelelo ya tshumelo dza muḓagasi wa mahala wa mutheo u fana na muḓagasi wa mahala wa mutheo, u ḓitika nga khuni vhuponi ha mahayani hu ḓo ḓi bvela phanḓa. / Department of Environmental Science / M.A. (Environmental Science)

Abstracts in English, Afrikaans and Southern Sotho / The purpose of this study was to develop a best practice corporate community involvement disclosures (CCID) framework for JSE-listed organisations in South Africa. An analysis of the literature underscored the need for quality CCID and revealed the paucity of research on this topic. The study adopted a mixed-methods approach employing three research stages. Firstly, an initial CCID framework was constructed on the basis of a content and document analysis of top-performing JSE-listed organisations. Secondly, 30 CCI experts refined and validated the CCID framework through semi-structured interviews. The developed CCID framework comprised 36 specific disclosure items in nine general disclosure categories. Thirdly, the CCID framework was applied to 116 corporate reports, including the integrated reports, sustainability reports and corporate webpages of 20 JSE-listed companies for the years 2015 to 2017. The findings indicated that the sample of JSE-listed organisations disclose some aspects of CCI in their corporate reports. However, there is no consistent reporting framework, and a number of CCID items were under-disclosed according to the CCI expert “best practice” to meet stakeholder expectations. In both the integrated and sustainability reports, general category 2, CCI strategy, and general category 4, CCI projects, were the best-performing categories. General category 8, Evidence of CCI, was one of the best-performing categories disclosed in the sustainability reports and on the corporate webpages. General category 5, Relevant regulatory measures, general category 6, CCI benefits/business value creation, and general category 7, Assurance of CCI reporting, contained no or limited CCID. The development of the CCID framework resonated with stakeholder theory, while the findings on the application of the CCID framework supported the theoretical perspectives of legitimacy theory. In addition to the identified legitimising drivers, the findings suggested that local tensions and expectations are impacting on CCID in South Africa. The findings of this study provide useful insights into CCID practices, guidelines and the quality of CCID. It is unique because it is the first of its kind to develop and apply a CCID framework in South Africa. The findings have a number of implications for stakeholders, corporate managers, regulators and policymakers in South Africa and internationally. / Die doel van hierdie studie was om ’n raamwerk van beste praktykte te ontwikkel vir korporatiewe gemeenskapsbetrokkenheid-openbaarmakings (KGBO) vir JSE-genoteerde organisasies in Suid-Afrika. ʼn Ontleding van die literatuur het die behoefte aan gehalte-KGBO beklemtoon en die gebrek aan navorsing oor hierdie onderwerp aan die lig gebring. Die studie het ’n gemengdemetode-benadering gevolg wat drie navorsingstadiums gebruik het. Eerstens is ʼn aanvanklike KGBO-raamwerk op die grondslag van ’n inhoud-en-dokument-ontleding van bes presterende JSE-genoteerde organisasies saamgestel. Tweedens het 30 KGB-kundiges die KGBO-raamwerk deur middel van halfgestruktureerde onderhoude verfyn en geldig verklaar. Die ontwikkelde KGBO-raamwerk het 36 spesifieke openbaarmaking-items in nege algemene openbaarmakingkategorieë bevat. Derdens is die KGBO-raamwerk toegepas op 116 korporatiewe verslae, insluitend die geïntegreerde verslae, volhoubaarheidsverslae en korporatiewe webbladsye van 20 JSE-genoteerde maatskappye vir die jare 2015 tot 2017. Die bevindings het aangetoon dat die monster van JSE-genoteerde organisasies enkele aspekte van KGBO in hul korporatiewe verslae openbaar het. Daar is egter nie ’n konsekwente verslagdoeningsraamwerk nie, en volgens die KGB-bestepraktykkundige is ’n aantal KGBO-items onderverklaar om aan belanghebbers se verwagtinge te voldoen. In sowel die geïntegreerde as volhoubaarheidsverslae was die algemene kategorie 2, KGB-strategie, en algemene kategorie 4, KGB-projekte, die bes presterende kategorieë. Algemene kategorie 8, Bewys van KGB, was een van die bes presterende kategorieë wat in die volhoubaarheidsverslae en op die korporatiewe webbladsye openbaar gemaak is. Algemene kategorie 5, Relevante regulatiewe maatreëls, algemene kategorie 6, KGB-voordele/besigheidswaarde-skepping, en algemene kategorie 7, Gerusstelling van KGB-verslagdoening, het geen of beperkte KGBO bevat. Die ontwikkeling van die KGBO-raamwerk het by die belanghebberteorie aanklank gevind, terwyl die bevindings van die toepassing van die KGBO-raamwerk die teoretiese perspektiewe van die egtheidsteorie gesteun het. Benewens die geïdentifiseerde egtheidsaandrywers het die bevindings daarop gesinspeel dat plaaslike spanning en verwagtinge ’n uitwerking op KGBO in Suid-Afrika het. Die bevindings van hierdie studie verskaf nuttige insigte in KGBO-praktyke, -riglyne en die gehalte van KGBO. Dit is uniek omdat dit die eerste keer is dat ’n KGBO-raamwerk in Suid-Afrika ontwikkel en toegepas word. Die bevindings het ’n aantal implikasies vir belanghebbendes, korporatiewe bestuurders, reguleerders en beleidmakers in Suid-Afrika en internasionaal. / Morero wa thutelo ye e be e le go tšweletša tlhako ya maitokiši a kaonekaone a dikutollo tša seabe sa dikgwebo setšhabeng (CCID) ya mekgatlo ye e lego lenaneong la JSE ka Afrika Borwa. Tshekatsheko ya dingwalo e gatelela tlhokego ya CCID ye e nago le mohola gape e utollotše nyakišišo ye e sa lekanago ka ga hlogotaba ye. Thutelo e tšere mokgwatebelelo wa mekgwa ye e tswakantšwego ka go diriša magato a mararo a dinyakišišo. Sa mathomo, tlhako ya mathomo ya CCID e hlamilwe go ya ka tshekatsheko ya diteng le tokomane tša mekgatlo ye e lego lenaneong la JSE yeo e šomago gabotse. Sa bobedi, ditsebi tša CCI tše 30 di kaonafaditše le go laetša boleng bja tlhako ya CCID ka mokgwa wa dipotšišo tšeo di sa latelego lenaneo leo le itšeng. Tlhako ya CCID ye e tšweleditšwego pele e dirilwe ke dintlha tša kutollo tše itšeng tše 36 magorong a kakaretšo a kutollo a senyane. Sa boraro, tlhako ya CCID e phethagaditšwe go dipego tša kgwebo tše 116, go akaretšwa dipego tše di kopantšwego, dipego tšeo di fago tshedimošo ka ga boemo bja tšwelelo ya kgwebo le matlakala a wepo a dikhamphani tše 20 tšeo di lego lenaneong la JSE mengwageng ya 2015 go fihla 2017 Dikhwetšo di šupile gore sampolo ya mekgatlo yeo e lego lenaneong la JSE e utollotše dintlha tše dingwe tša CCI dipegong tša tšona tša kgwebo. Le ge go le bjalo, ga go tlhako ya go bega ye e sa fetogego, gomme dintlha tše mmalwa tša CCID di utollotšwe ka mo go sa lekanago go ya ka “maitokišo a makaonekaone” a ditsebi tša CCI go kgotsofatša ditetelo tša bakgahlegi. Ka go dipego tše kopantšwego le tšeo di fago tshedimošo ka ga maemo a tšwelelo ya kgwebo, legoro la 2 la kakaretšo, le legoro la 4 la kakaretšo, diprotšeke tša CCI, di bile magoro ao a šomilego gabotse. Legoro la 8 la kakaretšo, Evidence of CCI, e bile ye nngwe ya magoro ao a šomilego gabotse ao a utollotšwego ka go dipego tšeo di fago tshedimošo ka ga boemo bja tšwelelo ya kgwebo le go matlakala a wepo a kgwebo. Legoro la 5 la kakaretšo 5, Relevant regulatory measures, legoro la 6 la kakaretšo 6, CCI benefits/business value creation, le legoro la 7 la kakaretšo, Assurance of CCI reporting, di be di se na le goba le CCID ya bogolo bjo beetšwego mellwane. Tšwetšopele ya tlhako ya CCID e kwana le mekgwaboitshwaro bolaoding bja kgwebo, mola dikhwetšo go tirišo ya tlhako ya CCID e thekga tebelelo ya ditlhalošo tša diteori tša go dira go ya ka mekgwa ya boitshwaro ya setšhabeng. Go tlaleletša go ditlhohleletši tše di šupilwego tša go amogelwa ka semolao, dikhwetšo di šišintše gore dithulano le ditetelo tša selegae di na le khuetšo go CCID ka Afrika Borwa. Dikhwetšo tša thutelo ye di fa ditshedimošo tše di ka thušago tša ditlwaetšo tša CCID, mekgwatlhahli le mohola wa CCID. Ke ya moswananoši ka gobane ke ya mathomo ya mohuta wa yona go tšweletša le go diriša tlhako ya CCID ka Afrika Borwa. Dikhwetšo di na le ditlamorago tše mmalwa go batho bao ba nago le dikgahlego, balaodi ba dikgwebo, basepetši go ya ka molao le badiramelaotshepetšo ka Afrika Borwa le kemong ya boditšhabatšhaba. / Management Accounting / D. Phil. (Accounting Sciences)