The present study investigated how 6 Korean graduate students at a Canadian university used a suite of multiple Web-based reference resources (named i-Conc), consisting of concordancers and dictionaries, as a cognitive tool for solving linguistic problems encountered over the course of completing—in English, their second language (L2)—an academic writing assignment for one of their graduate courses. Using a mixed methods design employing surveys, interviews, screen recordings, a query tracking log, and detailed case studies, the thesis provides rich descriptions of (a) the processes, and outcomes of the 6 participants’ uses of i-Conc as a reference tool for their writing authentic academic tasks and (b) their perceptions of the suite as a means of writing assistance. Overall, i-Conc served as an intellectual partner that aided the participants in strategically solving lexical and grammatical problems during their writing assignments: About 70 % of the problems they addressed with i-Conc resulted in correct text formulations or revisions. The different resources in i-Conc were each shown to have unique functions for which they were best suited, suggesting that concordancing may optimally be consulted in combination with, not in place of, other resources. The benefits of consulting i-Conc for L2 writing went beyond simply helping the participants’ problem solving to potentially facilitating their language acquisition. Input-feedback interactions with the reference suite prompted the participants to carry out robust meaning negotiations in their efforts to verify their intuitive hypotheses and to venture beyond their current linguistic repertoires. Participants acted on these potential benefits somewhat differently. Case studies and cross-case analyses demonstrated complex interactions between the participants’ individual traits and goals, the educational contexts for which they were writing, and their perceptions and evaluations of particular affordances provided by i-Conc. These findings imply that to build meaningful cognitive partnerships with reference tools, L2 writers should receive progressive guidance on principles for effective reference resource consultation along with training in strategies for using different types of resources, contingent on individuals’ abilities and ongoing needs arising from their macro and micro contexts for writing and for language learning.

The present study investigated how 6 Korean graduate students at a Canadian university used a suite of multiple Web-based reference resources (named i-Conc), consisting of concordancers and dictionaries, as a cognitive tool for solving linguistic problems encountered over the course of completing—in English, their second language (L2)—an academic writing assignment for one of their graduate courses. Using a mixed methods design employing surveys, interviews, screen recordings, a query tracking log, and detailed case studies, the thesis provides rich descriptions of (a) the processes, and outcomes of the 6 participants’ uses of i-Conc as a reference tool for their writing authentic academic tasks and (b) their perceptions of the suite as a means of writing assistance. Overall, i-Conc served as an intellectual partner that aided the participants in strategically solving lexical and grammatical problems during their writing assignments: About 70 % of the problems they addressed with i-Conc resulted in correct text formulations or revisions. The different resources in i-Conc were each shown to have unique functions for which they were best suited, suggesting that concordancing may optimally be consulted in combination with, not in place of, other resources. The benefits of consulting i-Conc for L2 writing went beyond simply helping the participants’ problem solving to potentially facilitating their language acquisition. Input-feedback interactions with the reference suite prompted the participants to carry out robust meaning negotiations in their efforts to verify their intuitive hypotheses and to venture beyond their current linguistic repertoires. Participants acted on these potential benefits somewhat differently. Case studies and cross-case analyses demonstrated complex interactions between the participants’ individual traits and goals, the educational contexts for which they were writing, and their perceptions and evaluations of particular affordances provided by i-Conc. These findings imply that to build meaningful cognitive partnerships with reference tools, L2 writers should receive progressive guidance on principles for effective reference resource consultation along with training in strategies for using different types of resources, contingent on individuals’ abilities and ongoing needs arising from their macro and micro contexts for writing and for language learning.

Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.

Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.

In this study, we address job sequencing and tool switching problem arising in Flexible Manufacturing Systems. We consider a single machine with limited tool slots on its tool magazine. The available tool slots cannot accommodate all the tools required by all jobs, therefore tool switches between jobs are required. A single tool transporter with limited capacity is used in transporting the tools from the storage area to the machine. Our aim is to minimize the number of tool transporter movements. We provide two mixed integer linear programming formulations of the problem, one of which is based on the traveling salesman problem. We develop a Branch-and-Bound algorithm powered with various lower and upper bounding techniques for optimal results. In order to obtain good solutions in reasonable times, we propose Beam Search algorithms. Our computational results reveal the satisfactory performance of the B&amp / B algorithm for moderate sized problems. Moreover, Beam Search techniques perform well for large-sized problems.

Immer mehr E-Learning-Zentren oder Medienstellen von Universitäten bieten Webkonferenztools nicht nur für die universitäre Forschung, sondern auch explizit für die universitäre Lehre an (siehe Abbildung 1). Für den Einsatz dieses Werkzeugs wird mit verschiedenen didaktischen Nutzungsszenarien, räumlich getrennten Kollaborationsmöglichkeiten, intensivierter synchroner Wissensvermittlung sowie der vollständigen Abbildung der Präsenzeinheiten auf Virtual Class rooms argumentiert. Auf Seiten der Lehrenden bedeutet der Einsatz von Webkonferenztools einen erhöhten Zeitaufwand an Lehrvorbereitung, -Abwicklung sowie -Nachbereitung. Diesem Zeitaufwand muss ein deutlicher didaktischer Mehrwert gegenüber stehen, wenn Webconferencing keine „Eintagsfliege“ in der präsenzuniversitären Lehre sein soll. Der didaktische Mehrwert kann in der Steigerung der Lehrqualität sowie der studentischen Kollaboration gesehen werden. Dieses Paper stellt nun unsere Erfahrungen – die aus einem langjährigen Einsatz des Webconferencingtools exzerpiert werden konnten – dar, diskutiert Stolpersteine und zeigt lehrqualitätssteigernde Szenarien auf.

Thesis (Ph. D.)--University of Pennsylvania, 1994. / Includes bibliographical references (leaves 245-252) and index.

Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Efficient face milling of titanium alloys provides a global challenge. Difficult-to-cut super alloys such as Ti-6Al-4V is considered the “workhorse” material for aerospace components. During the machining of aerospace components, 80% – 90% of the material is removed. This requirement drives the innovation for machines and tooling to become more efficient, while driving down costs. In South Africa, this requirement is no different. Due to the historic practice of exporting valuable minerals such as Ilmenite, leucoxene and rutile, South Africa does not enjoy many of financial benefits of producing value added titanium alloy products. The Titanium Centre of Competence (TiCoC) is aimed at creating a South African titanium manufacturing industry by the year 2020. More specifically, the roughing of Ti-6Al-4V aerospace components has been identified as an area for improvement. The thermal conductivity of Ti-6Al-4V is significantly lower than that of other “workhorse” metals such as steel or aluminium. Therefore, heat rapidly builds up in the tool tip during high speed machining resulting in shortened tool life and increased machining costs. Hence the ongoing developments in the field of cooling methods for high speed machining. The latest development in high pressure cooling (HPC) is split tools that deliver coolant into the cutting interface via flat nozzles in the rake face of the insert. Although it has been released recently and limited to a single supplier, this cooling method is commercially available, yet little is known about its performance or application conditions. The operational characteristics of split tools are studied by answering set research questions. A dynamometer was used to measure the tangential cutting forces during 11 cutting experiments that follow a three-factor factorial design at two levels and with three centre points. A second-order model for predicting the tangential cutting force during face milling of Ti-6Al-4V with split tools was fit to the data at 95% confidence level. A predictive cutting force model was developed in terms of the cutting parameters: (1) Axial depth of cut (ADOC), (2) feed per tooth and, (3) cutting speed. The effect of cutting parameters on cutting force including their interactions are investigated. Data for chip evacuation, surface finish and tool wear are examined and discussed. Practical work was done at a selected industry partner to determine: (1) impact of an analytical approach to perform process development for aerospace component roughing, (2) determine the feasibility of implementing split tools to an existing process. A substantial time saving in the roughing time of the selected aerospace component was achieved through analytical improvement methods. Furthermore it was found that the split tools were not a suitable replacement for current tooling. It was established that certain critical operational requirements of the split tools are not met by the existing milling machine at the industry partner. / AFRIKAANSE OPSOMMING: Doeltreffende masjinering van titaan allooie bied `n wêreldwye uitdaging. Moeilik-om-te-sny super allooie soos Ti-6Al-4V word as die “werksesel” materiaal vir lugvaart komponente beskou. Gedurende die masjinering van lugvaart komponente word 80% - 90% van die materiaal verwyder. Dit is hiérdie behoefte wat die innovering van masjien -en snygereedskap dryf om dit meer doeltreffend en finansieël vatbaar te maak. Die Suid Arikaanse behoefte vir doeltreffende snygereedskap vir Ti-6Al-4V masjinering stem ooreen met hierdie internationale behoefte. Die geskiedkundige Suid Afrikaanse praktyk om onverwerkte, waardevolle minerale soos Ilmeniet, rutiel en leucoxene uit te voer, kniehalter die land se kans om winste uit verwerkte titaan allooi produkte te geniet. Die “Titanium Centre of Competence” (TiCoC) se mikpunt is om `n Suid Afrikaanse titaanproduk vervaardigingsmark op die been te bring teen 2020. Stellenbosch Universiteit se funksie, binne hierdie strategiese raamwerk, fokus op hoë spoed masjinering van Ti-6Al-4V lugvaart komponente. Die hitte geleidingsvermoë van Ti-6Al-4V is noemenswaardig laer as die van ander “werksesel” materiale soos byvoorbeeld staal of alumium. Om hierdie rede word hitte in die freesbeitelpunt gedurende hoë spoed masjinering opgeberg. Dit verkort gereedskap leeftyd en verhoog masjinerings kostes. Daarvandaan deurlopende ontwikkelinge in verkoelingsmetodes vir hoë spoed masjinering. Die mees onlangse ontwikkeling in hoë druk verkoeling is “split tools” wat koelmiddel na die snyoppervlak deur middel van langwerpige gleufies in die hark gesig van die beitelpunt lewer. Hierdie tegnologie is op die mark beskikbaar, maar slegs deur `n enkele verskaffer. Daar is ook geen akademiese publikasies wat oor Ti-6Al-4V masjinering met “split tools” handel nie. Die verrigtings vermoë en toepassings gebied vir die gereedskap is steeds onbekend. 'n Dinamometer is gebruik om die tangensiale snykragte tydens 11 sny eksperimente te meet. Die eksperiment ontwerp is faktoriaal van aard en bevat drie faktore en drie middelpunte oor twee vlakke. `n Kwadratiese model is geskik om die data op 95% vertroue vlak voor te stel en voorspellings mee te maak. Die voorspellingsmodel is ontwikkel in terme van: (1) Diepte van snit, (2) voertempo, en (3) Snyspoed. Die invloed van die drie parameters op die tangentiale snykrag, asook invloed met mekaar word ondersoek. Verdere data in verband met materiaal verwydering, oppervlak afwerking en beitel slytasie word ook bespreek. Praktiese werk is met behulp van `n bedryfsvennoot gedoen om vas te stel: (1) die impak van 'n analitiese benadering en ontwikkelings proses op die uitrof van lugvaart komponente, (2) en om die lewensvatbaarheid van implementering van “split tools“ aan 'n bestaande proses te bepaal. `n Noemenswaardige besparing is sodoende behaal. Dit is verder bevind dat “split tools” nie `n geskikte plaasvervanger vir die huidige snygereedskap is nie. Die rede daarvoor is gedeeltelik omdat die huidige freesmasjien by die bedryfsvennoot nie aan die kritiese operasionele vereistes van die gereedskap vervaardiger voldoen nie.

Due to the continuous growth of patients with mental disorders, it has been a strenuous job to look after each patient and tailor the appropriate treatments for them on time. The thesis proposes a design science framework in the form of an IT artefact to prioritize the patients with mental disorders, considering the severity of the situation. The IT arte-fact will be using expert’s knowledge to design a self-assessment screen-ing tool that will evaluate the criticality of a patient’s mental health. This tool will also incorporate the psychometric scale DSM-5 Self-Rated Level 1 Cross-Cutting Symptom Measure, Adult electronically to de-termine what will be the next stage in the process of patients’ treat-ments. The process of prioritizing patients is prolonged and remains to be tedious at the hospital and also there is always a possibility of miss-ing some information while carrying out the job manually. The self-assessment system will serve two goals. It will shorten the initial screen-ing process and also the likelihood of any human error. The system is not meant to replace healthcare professionals but to build a bridge be-tween the patients and the doctors to make everyone’s life more orga-nized. The results indicate that it is possible to create a framework and the relevant prototype with the help of expert’s knowledge that can prioritize patients with mental disorders. It also demonstrates that the system can digitalize DSM-5 Self-Rated Level 1 Cross-Cutting Symp-tom Measure, Adult scale to determine possible problem domains for further diagnosis.

Este trabalho avalia o uso de insertos autolubrificantes de pó de aço ferramenta sinterizado para aplicação em ferramentas dos processos de Conformação a Frio. São apresentadas a preparação e a análise de diferentes composições de misturas de pós de aço ferramenta H 13. A Metalurgia do Pó convencional foi utilizada como processo para a obtenção dos insertos do estudo. Foram compactadas e sinterizadas misturas de pó de aço H13 com a adição de percentuais variados do lubrificante sólido Bissulfeto de Molibdênio – MoS2, também em pó, com o objetivo de atribuir propriedades de autolubrificação ao composto. O percentual de lubrificante sólido empregado nas amostras variou de 1% a 5%, com posterior sinterização. Os resultados obtidos no Ensaio de Atrito com anéis de Alumínio AA6351 recozido apresentaram nos insertos autolubrificantes do estudo coeficientes de atrito μ entre 0,10 e 015, menores que os valores μ entre 0,20 e 0,30 obtidos com aço H13 laminado convencional. Também o desgaste abrasivo do ferramental proposto avaliado no Ensaio de Abrasão com Roda de Borracha foi 12% menor quando comparado com o aço ferramenta H13 laminado exposto ao mesmo ensaio. / This study evaluates the use of self-lubricating tool steel powder sintered inserts for use in tools of Cold Forming processes. Preparation and analysis of various compositions of H13 tool steel powder mixtures are presented. The conventional Powder Metallurgy was used as a process for obtaining the study inserts. Were compacted and sintered mixtures of H13 steel powder with the addition of varying percentages of the solid lubricant Molybdenum Disulphide - MoS2, also in powder form, with the purpose of giving self-lubricating properties to the composite. The percentage of solid lubricant used in the samples varied from 1% to 5%, with subsequent sintering. The results of the friction test on AA6351 aluminum rings had friction coefficients μ between 0.10 and 015 with self-lubricating inserts in study, smaller than μ values between 0.20 and 0.30 obtained with the conventional steel H13 laminate. Also, the abrasive wear of the tooling proposed evaluated in the abrasion test with rubber wheel was 12% lower when compared to the H13 tool steel laminate exposed to the same test.