Context. The amount of training data required to build accurate modelsis a common problem in machine learning. Active learning is a techniquethat tries to reduce the amount of required training data by making activechoices of which training data holds the greatest value.Objectives. This thesis aims to design, implement and evaluate the Ran-dom Forests algorithm combined with active learning that is suitable forpredictive tasks with real-value data outcomes where the amount of train-ing data is small. machine learning algorithms traditionally requires largeamounts of training data to create a general model, and training data is inmany cases sparse and expensive or difficult to create.Methods.The research methods used for this thesis is implementation andscientific experiment. An approach to active learning was implementedbased on previous work for classification type problems. The approachuses the Mahalanobis distance to perform active learning via transduction.Evaluation was done using several data sets were the decrease in predictionerror was measured over several iterations. The results of the evaluationwas then analyzed using nonparametric statistical testing.Results. The statistical analysis of the evaluation results failed to detect adifference between our approach and a non active learning approach, eventhough the proposed algorithm showed irregular performance. The evalu-ation of our tree-based traversal method, and the evaluation of the Maha-lanobis distance for transduction both showed that these methods performedbetter than Euclidean distance and complete graph traversal.Conclusions. We conclude that the proposed solution did not decreasethe amount of required training data on a significant level. However, theapproach has potential and future work could lead to a working active learn-ing solution. Further work is needed on key areas of the implementation,such as the choice of instances for active learning through transduction un-certainty as well as choice of method for going from transduction model toinduction model.

Contraints par une pollution anthropique croissante, les environnementalistes explorent les avenues possibles pour réduire les émissions de contaminants émis en milieu urbain. Afin d'y parvenir, l'organisation du territoire favorisant le transport durable apparaît comme une alternative permettant de réduire l'empreinte écologique des déplacements quotidiens des habitants et ainsi de diminuer la pollution globale des villes. En effet, l'aménagement privilégiant un transport plus durable promeut une mixité des modes de transport et une proximité des usages à l'échelle des quartiers. En rapprochant la distance entre les usages, le transport actif, la forme la plus écologique de transport, devient plus attrayant pour la mobilité urbaine. La présente étude se penche sur neuf études de cas américaines et canadiennes en aménagement qui font la promotion du transport actif sur leur territoire. La recension des écrits révèle que plusieurs paramètres tels que la mixité des usages, la proximité, la connexion et certaines propriétés des réseaux piétonniers ou cyclables sont nécessaires à la mise en place d'un aménagement favorisant les déplacements en vélo et à pied. Ainsi, à l'aide d'une grille d'analyse rigoureuse, la description et la comparaison de certaines variables ont été réalisés [i.e. réalisées]. Il en ressort que la proximité est généralement bonne alors que la connectivité est plutôt modérée. Les propriétés des réseaux sont très spécifiques à chacune des études de cas, mais elles témoignent d'une certaine unité. Les variables relatives à l'environnement, à la sécurité, aux coûts et à la ségrégation des voies sont relativement présentes tandis que celles touchant au design, au confort, au mobilier, aux infrastructures lourdes et à l'entretien le sont beaucoup moins. Ces analyses permettent de mettre de l'avant certaines pratiques et d'émettre des recommandations pour de futurs projets en aménagement favorisant le transport actif.

In this paper we give a general framework for isotone optimization. First we discuss a generalized version of the pool-adjacent-violators algorithm (PAVA) to minimize a separable convex function with simple chain constraints. Besides of general convex functions we extend existing PAVA implementations in terms of observation weights, approaches for tie handling, and responses from repeated measurement designs. Since isotone optimization problems can be formulated as convex programming problems with linear constraints we then develop a primal active set method to solve such problem. This methodology is applied on specific loss functions relevant in statistics. Both approaches are implemented in the R package isotone. (authors' abstract)

India is the world’s largest democracy where 1 186 200 000 people live and almost half of these are women. So how does women’s situation effect India’s development. This essay focuses on secondary education, female labor force participation and active population growth and measures their affect on Human Development Index (HDI). The literature shows a positive effect of all explanatory variables on HDI. In other an effective resource allocation towards words women might be the key for India to reach higher living standards. It is indeed a question of effective resource allocation because women in India don’t enjoy the same freedoms and rights as men which will clearly effect the countries resource allocation and the HDI

No description available.

The domain of distributed simulation is growing rapidly. This growth leads to larger and more complex supporting network architectures with high requirements on availability and reliability. For this purpose, efficient fault-monitoring is required. This work is an attempt to evaluate the viability of an Active probing approach in a distributed simulation system in a wide area network setting. In addition, some effort was directed towards building the probing-software with future extensions in mind. The Active probing approach was implemented and tested against certain performance requirements in a simulated environment. It was concluded that the approach is viable for detecting the health of the network components. However, additional research is required to draw a conclusion about the viability in more complicated scenarios that depend on more than the responsiveness of the nodes. The extensibility of the implemented software was evaluated with the QMOOD-metric and not deemed particularly extensible.

Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: The surfmers sodium l l-rnethacryloyloxy undecanyl-I sulfate (MET) and sodium 11- crotonoyloxy undecanyl-I sulfate (CRO) were synthesized and purified. Both contain a sulfonate and polymerizable double bond connected by a hydrocarbon chain. Sodium 4-[ 11- (3-carboxypropionoyloxy)-undecyloxy] benzenesulfonate (PSA-MA) could not be synthesized successfully. MET and CRO were characterized by means of nuclear magnetic resonance spectroscopy (NMR), elemental analysis (EA), thermal gravimetric analysis (TGA), determination of the critical micelle concentration (CMC), differential scanning calorimetry (DSC), and microscopy. MET and CRO displayed a liquid crystalline behavior. MET and CRO were used in combination with poly(diallyl dimethyl ammonium chloride) to form polyelectrolyte-surfactant complexes by common precipitation in water. These complexes were redissolved in methanol and cast in films. The cast films were investigated by wide angle X-ray scattering (WAXS) and small angle X-ray scattering (SAXS) with regard to ordered mesomorphous phases. Due to the destabilization of the lyotropic phase, little order were observed in the complexes. MET was co-polymerized with styrene and methyl methacrylate, in different proportions, by means of free radical polymerization. The co-polymers were characterized by NMR and infrared spectroscopy (Ik) and analyzed by DSC, TGA and gel permeation chromatography (GPC). All analytical techniques showed that the co-polymers were synthesized successfully. TEM indicated a fine, lamellar micro-structure. / AFRIKAANSE OPSOMMING: Die polimeriseerbare sepe, natrium-ll-metakrieloloksi-undekaniel-l sulfaat (MET) en natrium-ll-krotonieloksi-undekaniel-l-sulfaat (CRO) is berei en gesuiwer. Beide bevat 'n sulfonaat en 'n polimeriseerbare dubbelbinding wat deur 'n koolwaterstofketting verbind word. Natrium-4-[11-(3-karboksipropionieloksi)-undekieloksi]-benseensulfaat (PSA-MA) kon nie suksesvol berei word me. MET en CRO is deur middel van kernmagnetieseresonansspektroskopie (KMR), elementele-analise (EA), termiesegravimetriese analise (TOA), kritiese miselkonsentrasie (CMC), differensieelskandeerkalorornetrie (DSC) en mikroskopie gekarakteriseer. Beide MET en CRO het 'n vloei-kristalgedrag getoon. MET en CRO is met poli(diallieldimetielammoniumchloried) gereageer om polyelektrolietseepkompleks te vorm deur presipitasie uit water. Die komplekse is in metanol opgelos en films daarvan gemaak. Die films is deur wyehoek X-straal diffraksie (WAXS) en kleinhoek X-straaldiffraksie (SAXS) ondersoek om geordende mesomorfiese fases te ondersoek. As gevolg van destabilisasie van die liotropiese fase is min orde in die komplekse gevind. MET is met stireen en metielmetakrilaat deur middel van vryeradikaalpolymerisasie gekopolimeriseer. Die kopolimere is deur middel van KMR- en infrarooispektroskopie (IR), DSC, TOA en gelpermeasiechromotagrafie (OPC) ondersoek. Al hierdie analitiese metodes het die suksesvolle sintese van die kopolimere bewys. Transmissie-elektronmikroskopie het die teenwoordigheid van 'n fyn, laminere mikro-struktuur bewys.

Observations of neutral hydrogen (HI) absorption in the central regions of eight active galaxies are reported. These observations represent the most detailed studies of the neutral hydrogen component so far made of these sources, providing information on the HI gas distribution and kinematics on scales of 0.2 arcsec, corresponding to linear scales of tens of parsecs in the nearest galaxies observed. The sample of active galaxies presented here consists of the radio galaxy 3C293, two Seyfert galaxies NGC7674 and NGC7469, and five luminous infrared galaxies; NGC6240, IIIZw35, UGC2369, IR0335+1523 and Zw049.0. In each of these galaxies MERLIN has been used to provide the highest angular resolution observations of the neutral hydrogen content in these sources made to date. In addition to these high resolution HI studies the newly operational Giant Meterwavelength Radio Telescope has also been used to provide arcsecond resolution observations of the HI gas content in two of the MERLIN sources, 3C293 and NGC7674.Against the central few kiloparsecs of the radio galaxy 3C293 both the neutral hydrogen distribution and the radio continuum emission is imaged on linear scales of 150pc. The distribution and velocity structure of the HI gas against this radio galaxy is attributed to two gas structures. One of these gas structures is indicative of quiescent gas lying 10kpc from the galaxy centre and is physically associated with both ionised gas and dust lanes in the galaxy. The second HI velocity structure is situated within 600pc of the active galactic nucleus (AGN) and is observed to form a circumnuclear disc with a velocity gradient of 179km/s/arcsec. This circumnuclear disc of gas is shown to enclose a mass of M_dyn<600pc)leq3.9*10^9(sin^{-2}i) Msolar, where i represents the inclination of the disc. Extremely localised HI absorption is observed against the unresolved nuclei of the Seyfert galaxies NGC7674 and NGC7469. In the case of the Seyfert-2 galaxy NGC7674, it is shown that the HI is distributed within a 100pc of the AGN. Against the unresolved Seyfert-1 nucleus of NGC7469 the HI absorption is thought to either result from quiescent gas in the outer parts of this galaxy or from gas close to the nucleus. The HI absorption distribution in both of these sources is consistent with the absorption arising in circumnuclear dusty tori. Of the five luminous infrared galaxies observed, HI absorption is detected in four cases. The observations of IIIZw35, IR0335+015 and Zw49.0 all revealed unresolved 1.4GHz radio continuum structure against which HI absorption is detected. However, against the prototypical luminous infrared merger NGC6240 extensive radio continuum is resolved and imaged. It is concluded that the radio continuum structure of NGC6240 is consistent with the radio emission arising from both a starburst region and one or two AGN existing in the remnant nuclei of the merging galaxies. Extremely broad HI absorption is detected against the two dominant radio continuum components. The HI gas structure is consistent with a neutral gas disc forming between the two merging nuclei as they orbit around each other.

Thesis (MEd)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Relevant literature in higher education indicates that the higher education scene is changing fast and that higher education providers and their educators are at the centre of such change. The changing student body is of particular interest to higher education providers as the changing needs of students result in new inquiries into how current students learn and perform. Student engagement is widely suggested as a means of addressing the changing nature of the current generation of students and enhancing student success. Student engagement may be defined as the time and effort students devote to activities that are empirically linked to the desired higher education outcomes. Student success is no longer considered merely as cognitive competence as there is a greater understanding today of what makes up the entire student and his or her learning needs. This study was aimed at determining to what extent student engagement is being promoted at a private higher education institution in the Western Cape, South Africa. A mixed method research design was applied. Self-constructed questionnaires were distributed to staff members and students at the institution and semi-structured interviews with individual staff members and focus group interviews with students were also conducted. Both quantitative and qualitative data were generated and appropriately analysed. From the findings of this study a number of issues emerged. Firstly, it was revealed that the institution as a private provider in the field of culinary arts and hospitality and its educators recognise the changing nature of their students. Secondly, staff seem committed to the concept of student engagement and related practices to foster student success. Thirdly, students acknowledge engagement in their own learning as a favourable feature, but indicate further engagement opportunities to be created by their lecturing staff and the institution. A number of implications also emerged from the study. It is evident that lecturers at The Private Hotel School may aim to gain a better understanding of the current generation of students and they may also focus on determining more ways to facilitate engagement. Furthermore, it is evident that students at this institution may be made more aware of their role in engaging in their own learning. / AFRIKAANSE OPSOMMING: Die relevante literatuur in hoër onderwys dui daarop dat die hoëronderwysomgewing besig is om vinnig te verander en dat die verskaffers van hoër onderwys en hul opvoeders sentraal staan in sulke verandering. Die veranderende behoeftes van studente dien as aansporing vir nuwe navorsing oor hoe teenswoordige studente leer en presteer; gevolglik is die veranderende studenteliggaam van besondere belang vir die verskaffers van hoër onderwys. Daar word algemeen aanbeveel dat studentebetrokkenheid ondersoek word om die veranderende aard van die huidige geslag studente te verken en studentesukses te verhoog. Studentebetrokkenheid kan gedefinieer word as die tyd en moeite wat studente aan aktiwiteite wy wat empiries verbind kan word met verlangde uitkomste in hoër onderwys. Studentesukses word nie meer gesien as slegs kognitiewe bevoegdheid nie aangesien daar tans meer begrip is van wat die hele student en sy of haar leerbehoeftes behels. Die doel van hierdie navorsing was om te bepaal tot watter mate studentebetrokkenheid bevorder word by ʼn private hoëronderwysinstelling in die Wes-Kaap, Suid-Afrika. ʼn Gemengde-metode navorsingsontwerp is gebruik, en self-opgestelde vraelyste is aan personeellede en studente by die instelling uitgedeel. Semi-gestruktureerde onderhoude is gevoer met individuele personeellede en fokusgroep-onderhoude is met studente gedoen. Beide kwantitatiewe en kwalitatiewe data is gegenereer en toepaslik ontleed. ʼn Aantal kwessies het vanuit die bevindinge van hierdie studie aan die lig gekom: Eerstens, dat die opvoeders van die instelling as ʼn private verskaffer op die terrein van kulinêre kuns en gasvryheid die veranderende aard van hul studente herken; tweedens, dat die personeel verbind is tot die bevordering van studentebetrokkenheid en verwante praktyke om studentesukses te bevorder; en derdens, dat studente betrokkenheid in hul eie leerproses as ʼn positiewe doelstelling beskou, maar dat verdere geleenthede tot betrokkenheid geskep kan word deur hul doserende personeel en die instelling. ʼn Aantal verdere implikasies het ook vanuit hierdie studie aan die lig gekom. Dit is duidelik dat dosente by The Private Hotel School nog ʼn groter poging kan aanwend om die huidige geslag studente beter te begryp en dat hulle ook kan probeer om meer maniere te vind om studentebetrokkenheid te fasiliteer. Dit blyk verder dat studente by hierdie instelling nog meer bewus kan raak van hoe hulle self tot groter betrokkenheid by hulle eie leerproses kan bydra.

published_or_final_version / Social Work and Administration / Doctoral / Doctor of Philosophy