Thesis (DPhilAgric)--Stellenbosch University, 2002 / ENGLISH ABSTRACT: South Africa is one of the worlds leading producers of chicory (Cichorium intybus L.). Most of the chicory produced is used locally for the production of instant coffee. Witloof chicory, or Belgian endive, however, is a vegetable crop grown from the root of Cichorium intybus L. var. foliosum. This is done by placing the mature taproot in a controlled, dark environment after vernalization and supplying it with water and nutrients by means of hydroponics. Witloof chicory is new to the South African market and is only produced on a limited scale. Nonetheless, seeing that chicory is successfully grown on a large scale for the coffee industry it seemed reasonable to investigate the cultivation of this essentially unknown vegetable locally. The focus of this study was on the evaluation of new witloof production techniques during the second stage of witloof (chicon) cultivation, also called 'forcing'. To this end, locally grown witloof chicory roots were used in all trials. In order to establish the effects of several irrigation methods on lateral root formation and chicon quality, witloof chicory roots were forced using the conventional means of hydroponic irrigation as well as ebb-and-flood and aeroponic irrigation. Lateral root formation was significantly increased when either ebb-and-flood or aeroponic irrigation was applied compared to that obtained with the conventional method. This increase in lateral root formation was, however, to the detriment of chicon quality (QI), possibly as a result of competition for limited carbohydrate reserves. In an attempt to optimize the aeroponic irrigation method, roots were forced in non-vertical positions. Placing roots horizontally during forcing resulted in a significantly lower marketable chicon yield than where roots were placed vertically. The loss in yield was probably brought about by an increased fallout percentage rather than by a decrease in chicon production. Considering the pivotal role that sucrose plays in the development of the chicory head, sucrose was applied exogenously to the root before and/or during forcing. Dry matter chicon yield was negatively effected by exogenously applied sucrose. This could have been due to an increased incidence of fungal or bacterial infections or causative of roots absorbing less water resulting in the inability of the plant to utilize the applied sucrose during chicon development. Fungal and bacterial infections are known to have a detrimental effect on witloof chicory production. An environmentally friendly product for disease control, 'Desogerme SP®', was used to contain or reduce infection. Irrigation of roots with 'Desogerme SP®' containing nutrient solution increased chicon yield by 31%. From this study it became clear that some new production techniques applied had the potential of improving lateral root formation or quality during growth. However, the conventional way of irrigation remains the most effective compared to the other techniques applied, but could possibly be improved to some extent by incorporating 'Desogerme SP®' either as a pretreatment or in the nutrient solution. A breakthrough was made with the development of the quality index (QI). The ongoing limitation of statistically analyzing quality data of chicons sorted according to quality-classes was overcome by making use of this tool. Despite the fact that the index was developed specifically for use on witloof, it is has the potential of being applied to quality data of a wide variety of crops. / AFRIKAANSE OPSOMMING: Suid Afrika is een van die wêreld se grootste produsente van sigorei (Cichorium intybus L.). Die meeste plaaslik geproduseerde sigorei word vir die produksie van kitskoffie benut. Witloofsigorei, of Belgiese "endive", is egter 'n groentegewas wat vanaf die wortel van Cichorium intybus L. var. foliosum gekweek word. Dit word gedoen deur die volwasse penwortel na vemalisasie in 'n gekontroleerde, donker omgewing te plaas en met 'n hidrokultuurstelsel van water en voedingselemente te voorsien. Witloof is nuut op die Suid Afrikanse mark en word net op beperkte skaal geproduseer. Aangesien sigorei suksesvolop groot skaal vir die koffieindustrie geproduseer word, blyk dit logies om die moontlikhede te ondersoek om hierdie relatief onbekende groente plaaslik te kweek. Die fokus van hierdie studie was gerig op die evaluasie van nuwe produksietegnieke gedurende die tweede fase van witloofproduksie, wat ook as forsering bekend is. Plaaslik gekweekte witloof sigoreiwortels is vir alle eksperimente gebruik. Die invloed van 'n verskeidenheid besproeiingsmetodes is op sywortelproduksie en witloof krop-kwaliteit ondersoek. Witloofwortels is geforseer deur van 'n konvensionele hidrokultuur-stelsel gebruik te maak wat met 'n ebb-en-vloed en 'n lugsproei sisteem vergelyk is. Sywortel-produksie was betekenisvol hoër waar ebb-en-vloed of lugsproei sisteme toegepas is. Hierdie verbetering in sywortel-ontwikkeling was egter tot nadeel van krop-kwaliteit, vermoedelik as gevolg van die allokasie van koolhidrate na sywortels, eerder as na die groeipunt. In 'n poging om die lugsproei besproeiingsmetode te verbeter en om swamsiektes te verminder, is wortels in nie-vertikale posisies geforseer. Wortels wat gedurende forsering horisontaal ingetafel was, het 'n betekenisvol laer opbrengs van bemarkbare kroppe getoon as wortels wat vertikaal geplaas was. Die verlies aan opbrengs kon toegeskryf word aan 'n verhoging van afval, aangesien geen betekenisvolle afname in vars krop-gewig gevind is nie. Aangesien sukrose 'n belangrike rol in die ontwikkeling van die witloofkrop speel, is sukrose voor en tydens forsering aan die wortels toegedien. Droë materiaal krop-opbrengs is negatief deur die toediening van sukrose beïnvloed. Dit kon moontlik as gevolg van 'n verhoogde voorkoms van swam- of bakteriese infeksies gewees het of 'n aanduiding wees dat behandelde wortels minder water geabsorbeer het en die toegediende sukrose nie kon gebruik gedurende krop-ontwikkeling me. Swam- en bakteriese infeksies is bekend vir hul negatiewe uitwerking op witloofproduksie. 'n Omgewingsvriendelike middel, 'Desogerme SP®' is gebruik om siektes te beheer ofte verminder. Wortels wat met 'n 'Desogerme SP®' bevattende voedingsoplossing besproei is, het 'n 31% verhoging in krop-opbrengs getoon. Uit data wat gedurende hierdie studie ingesamel is, blyk dit duidelik dat sommige van die nuwe produksietegnieke wel die potensiaal het om sekere planteienskappe te verbeter. In geheel gesien bly die konvensionele metode van besproeiing die mees effektiewe, wanneer dit vergelyk word met die ander wat getoets is. Die konvensionele metode kan moontlik verbeter word as 'Desogerme SP®' as 'n vooraf-behandeling of as deel van die voedingsoplossing geïnkorporeer word. 'n Deurbraak is met die ontwikkeling van 'n kwaliteitsindeks (QI) gemaak. Ernstige beperkings word met statistiese ontledings van kwaliteitsdata ervaar waar kroppe volgens kwaliteitskiasse gesorteer word. Hierdie probleme is met behulp van die QI oorkom. Ongeag die feit dat die indeks spesifiek vir gebruik by witloof ontwikkel is, het dit die potensiaal om toepassing te vind by 'n wye reeks landboukundige produkte.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-07-18T18:26:58Z No. of bitstreams: 1 Rafael Kreling_.pdf: 3132334 bytes, checksum: c0e4ea129a81ca3c0ede5f40c054bc30 (MD5) / Made available in DSpace on 2016-07-18T18:26:58Z (GMT). No. of bitstreams: 1 Rafael Kreling_.pdf: 3132334 bytes, checksum: c0e4ea129a81ca3c0ede5f40c054bc30 (MD5) Previous issue date: 2016-03-31 / Nenhuma / A literatura de Estratégia de Produção, que aborda desde o conceito de Unidades Estratégicas de Negócio (UEN), passando pelas diferentes Dimensões da Competição, evoluindo também para o conceito de Fábrica Focada de Skinner e culminando na definição das diferentes técnicas e práticas de produção que alavancam cada uma das Dimensões Competitivas, é ampla. Porém, quando o objetivo é determinar quais técnicas priorizar diante de um rol grande de opções, este tema já é mais restrito. A lacuna que existe pode ser resumida na seguinte pergunta: diante de uma situação real específica, haveria um método que auxiliasse na escolha da(s) técnica(s) mais adequada(s) a se adotar? Essa pesquisa propõe-se a preencher esta lacuna, sugerindo um método que direcione a tomada de decisão do usuário na definição das técnicas de produção mais adequadas a serem adotadas em sua realidade industrial específica. A pesquisa se concentrou no estudo literário individual das técnicas de produção que eram comuns aos autores que as estudaram, destacando as contribuições de Antunes Júnior (2013), Pacheco (2012) e Ghinato (2000). O método proposto teve a crítica de cinco especialistas acadêmicos/profissionais do tema, tendo posteriormente a aplicação junto a um gestor industrial de uma empresa. O método de pesquisa adotado foi o Design Research. O método final proposto, que auxilia na seleção das técnicas de produção mais alinhadas à realidade de aplicação, procurou avançar mais um passo no desdobramento da Estratégia de Produção, apoiando gestores industriais na adoção de técnicas e práticas, segundo suas principais demandas e condições específicas vividas. Esta customização de um pacote genérico de opções de técnicas e práticas para a realidade específica se demonstrou adequada na aplicação do método. Para trabalhos futuros, se recomenda a pesquisa de técnicas para os tipos de sistemas produtivos distintos aos direcionados desta pesquisa, assim como outras abordagens, às quais as técnicas pertencem, sejam incorporadas. / The manufacturing strategy literature is very wide and approaches concepts such as Strategic Business Units (SBU) and Competitive Dimensions, evolves towards the concept of Focused Factory by Skinner and culminates in the definition of different techniques, systems and tools that leverage each Competitive Dimension. However, the literature is much more restricted when it comes to determining which particular manufacturing technique should be adopted among different possibilities. Its gap can be summarized in the following question: in a given real situation, is there a method that could help choose the most appropriate technique(s) to adopt? This work aims at filling this gap by proposing a method which directs decision-making when one needs to define the most appropriate production technique(s) to be adopted within a specific industrial reality. The research focused on the individual literature review of the production techniques that were common to the authors that studied them, especially the contributions from Antunes Júnior (2013), Pacheco (2012) and Ghinato (2000). The proposed method underwent the critical analysis from five academic/professional specialists, followed by an experimental application carried out by an industrial manager. The research method adopted is called Design Research. The final method proposed assists its user to select the production techniques that are best aligned with a given application reality. It seeks to go one step further in unfolding Production Strategy by supporting industrial managers to adopt techniques and practices that meet their main demands and specific conditions experienced in their daily routines. This customization of a generic package of techniques and practices for the specific reality has proven to be suitable in the method application. For future studies, it is recommended research on techniques for different types of production systems not covered in this research, as well as other approaches, which the techniques belong to, should be incorporated.

The primary research strategy of this study was to elicit meaningful answers from viewers by means of a focus-group procedure; this is a method associated with qualitative research (see Creswell, 1998; Berg & Lune, 2011) The group consisted of ten adults, whose visual literacy in terms of narrative films, was described as high (they frequently watch films at home, or in the theatre). The researcher acted as the moderator; and a set of semi-structured questions, based on meanings attached to camera-angle codes as defined by Mascelli, were answered by the participants. The codification scheme of Mascelli was applied to the unconventional camera angles in Avatar and The English Patient. These were compared with the viewers’ responses. Finally, the results were interpreted, in order to establish whether a meaningful relationship exists between the viewers’ responses and the interpretation of unconventional camera angles by such a seminal figure as Joseph V. Mascelli. The literature study focused on a media aesthetic explanation of cinematography, which included media aesthetics theory, framing, and composition, as well as the general codes and conventions relevant to cinematography. The literature overview includes a study of books, academic articles, internet sources, legislation, and training videos. A Nexus and EbscoHost search (Academic Search Premier and Jstor) was conducted on cinematography in general, and on camera angles in particular. Chapter 5 indicates the viewers’ overall interpretations of the unconventional camera angles used in Avatar and The English Patient. The graphs in Chapter 5 indicate that the viewers found the unconventional camera angles used in the films to represent the meaning of the shots appropriately, and that they understood why each unconventional camera angle had been used. The viewers’ responses correspond with the meanings of the unconventional camera angles, as stated by Mascelli. To ensure the effectiveness of a film and the accurate representation of the meanings of camera angles and camera sizes, the way it is described by Mascelli should ideally be taken into consideration by all future producers. Mascelli’s descriptions of camera angles and camera sizes, combined with the media aesthetics, as described by Zettl – when successfully applied – could lead to the production of a good quality film and images within the film. / MA (Communication Studies), North-West University, Potchefstroom Campus, 2014

The primary research strategy of this study was to elicit meaningful answers from viewers by means of a focus-group procedure; this is a method associated with qualitative research (see Creswell, 1998; Berg & Lune, 2011) The group consisted of ten adults, whose visual literacy in terms of narrative films, was described as high (they frequently watch films at home, or in the theatre). The researcher acted as the moderator; and a set of semi-structured questions, based on meanings attached to camera-angle codes as defined by Mascelli, were answered by the participants. The codification scheme of Mascelli was applied to the unconventional camera angles in Avatar and The English Patient. These were compared with the viewers’ responses. Finally, the results were interpreted, in order to establish whether a meaningful relationship exists between the viewers’ responses and the interpretation of unconventional camera angles by such a seminal figure as Joseph V. Mascelli. The literature study focused on a media aesthetic explanation of cinematography, which included media aesthetics theory, framing, and composition, as well as the general codes and conventions relevant to cinematography. The literature overview includes a study of books, academic articles, internet sources, legislation, and training videos. A Nexus and EbscoHost search (Academic Search Premier and Jstor) was conducted on cinematography in general, and on camera angles in particular. Chapter 5 indicates the viewers’ overall interpretations of the unconventional camera angles used in Avatar and The English Patient. The graphs in Chapter 5 indicate that the viewers found the unconventional camera angles used in the films to represent the meaning of the shots appropriately, and that they understood why each unconventional camera angle had been used. The viewers’ responses correspond with the meanings of the unconventional camera angles, as stated by Mascelli. To ensure the effectiveness of a film and the accurate representation of the meanings of camera angles and camera sizes, the way it is described by Mascelli should ideally be taken into consideration by all future producers. Mascelli’s descriptions of camera angles and camera sizes, combined with the media aesthetics, as described by Zettl – when successfully applied – could lead to the production of a good quality film and images within the film. / MA (Communication Studies), North-West University, Potchefstroom Campus, 2014

Die Arbeit hat das Ziel, auf der Grundlage der natürlichen Standortfaktoren die Entwicklung der Getreideproduktion zwischen den Jahren 1900 und 2000 aufzuzeigen. Dabei sollen die Betrachtungszeiträume historischen Ereignissen, die Rahmenbedingungen für die Produktion bilden, angepasst werden. Für die recht unterschiedlichen Zeiträume werden für die einzelnen Getreidearten die Erträge ermittelt und der jeweils erzielte lineare Ertragsanstieg errechnet. Daran schließt sich dann eine Darstellung des spezifischen Produktionsverfahrens an, um die Ursachen für den erzielten Ertragsanstieg in der jeweiligen Periode aufzuzeigen. Die Verfahrensanalyse erstreckt sich auf die Einordnung in die Fruchtfolge, die Bodenbearbeitung und Bestellung, sowie auf die Düngung, Pflege und Ernte. Die Maßnahmen des Pflanzenschutzes werden nur sehr allgemein im Rahmen der Pflege des Getreides behandelt und die Züchtung begrenzt sich auf erforderliche Hinweise im Rahmen der Ertragsentwicklung. Es werden mehr die Einflüsse der klassischen acker- und pflanzenbaulichen Maßnahmen auf die Getreideproduktion im genannten Zeitraum innerhalb bestimmter Perioden, für die gleichen Rahmenbedingungen gelten, analysiert. Grundlage bilden die langjährigen Angaben über die Erträge der Getreidearten, die im Statistischen Landesamt vorliegen und Veröffentlichungen in Form von Lehrbüchern und Artikeln in Fachzeitschriften des zurückliegenden Jahrhunderts. Gewisse Probleme bereitet die Differenzierung zwischen Erkenntnisfortschritt und tatsächlicher Anwendung in der Praxis. Bestehende Disproportionen werden besonders bei dem Vergleich von Empfehlungen und statistischen Angaben zur Düngung offensichtlich, um ein charakteristisches Beispiel zu nennen. In der Arbeit wird an den betreffenden Stellen darauf hingewiesen. Neben diesen Quellen wurden für Zeiten mit eingeschränkten Publikationsnachweisen noch ältere Landwirte als Zeitzeugen befragt. Dadurch konnten wesentliche Lücken geschlossen werden. Im Ergebnis der analytischen Betrachtung sollen Lösungen für die Getreideproduktion der kommenden Jahre in Mecklenburg-Vorpommern aufgezeigt werden. Dabei wird dem Getreideanbau auf den Grenzstandorten besondere Beachtung zugemessen. / The objective of this work is to demonstrate the development of cereal production between 1900 and 2000 based on natural site-specific factors. In so doing, the periods under consideration are to be studied in correlation with the historical events that formed the framework conditions for production. For each of the various periods, the yields for individual cereal types shall be determined and the respective linear increases in yield shall be calculated. This will be followed by a representation of specific production procedures in order to demonstrate the reasons for the increases in yield for each period. The procedural analysis will cover the categories of crop rotation, soil preparation and treatment, fertilisation, care of crops and harvesting. Crop protection measures will only be touched on generally as is relevant to the care of cereals, and the consideration of cultivation will be limited to necessary indications pertaining to yield development. The work shall, instead, focus on the analysis of the influences of traditional agricultural and horticultural measures on cereal production in the aforementioned period within certain timeframes in which the same framework conditions are present. The basis for this study is formed by several years' worth of data on various cereal yields available from the national statistics office as well as textbook publications and articles in trade publications from the previous century. Certain problems arise when differentiating between the acquisition of knowledge and the actual widespread application thereof. To name a typical example, existing disproportions become particularly obvious when comparing recommendations and statistical details for fertilisation. References shall be made to such discrepancies where appropriate. In addition to theses sources, older generation farmers have been polled as witnesses of time periods for which limited data was available in the form of publications. This approach enabled significant gaps in information to be filled. The objective of these analytical results is to indicate solutions for future cereal production in Mecklenburg-Western Pomerania. Special consideration will be given to the cultivation of cereals in border locations.

This work describes three alternative processes for producing microfibrillated cellulose (MFC; also referred to as cellulose nanofibrils, CNF) in which bleached pulp fibres are first pretreated and then homogenized using a high-pressure homogenizer. In one process, fibre cell wall delamination was facilitated by a combined enzymatic and mechanical pretreatment. In the two other processes, cell wall delamination was facilitated by pretreatments that introduced anionically charged groups into the fibre wall, by means of either a carboxymethylation reaction or irreversibly attaching carboxymethylcellulose (CMC) to the fibres. All three processes are industrially feasible and enable energy-efficient production of MFC. Using these processes, MFC can be produced with an energy consumption of 500–2300 kWh/tonne. These materials have been characterized in various ways and it has been demonstrated that the produced MFCs are approximately 5–30 nm wide and up to several microns long. The MFCs were also evaluated in a number of applications in paper. The carboxymethylated MFC was used to prepare strong free-standing barrier films and to coat wood-containing papers to improve the surface strength and reduce the linting propensity of the papers. MFC, produced with an enzymatic pretreatment, was also produced at pilot scale and was studied in a pilot-scale paper making trial as a strength agent added at the wet-end for highly filled papers. / <p>QC 20150126</p>

This work describes three alternative processes for producing microfibrillated cellulose (MFC) in which pulp fibres are first pre-treated and then homogenized using a high-pressure homogenizer. In one process, fibre cell wall delamination was facilitated with a combined enzymatic and mechanical pre-treatment. In the two other processes, cell wall delamination was facilitated by pre-treatments that introduced anionically charged groups into the fibre wall, by means of either a carboxymethylation reaction or irreversibly attaching carboxymethyl cellulose (CMC) onto the fibres. All three processes are industrially feasible and enable production with low energy consumption. Using these methods, MFC can be produced with an energy consumption of 500–2300 kWh/tonne, which corresponds to a 91–98% reduction in energy consumption from that presented in earlier studies. These materials have been characterized in various ways and it has been demonstrated that the produced MFCs are approximately 5–30 nm wide and up to several microns long. / <p>QC 20120928</p>

La Història del vidre a Mallorca entre els segles XIV i XVIII està determinada per la forta influència exercida per la vidrieria catalana i la veneciana. El marc cronològic ampli té la finalitat de precisar les continuïtats i canvis que es produeixen en l'artesanat. En aquest sentit, s'ha de destacar com un factor fonamental la presència de vidriers procedents d'Itàlia, que situen l'illa de ple en les dinàmiques que caracteritzen l'art del vidre. Per a cada època s'han situat els principals obradors, les famílies de vidriers i els sistemes de treball desenvolupats. En relació als objectes catalogats, hem constatat l'arribada d'importacions islàmiques, catalanes i venecianes. Les tipologies s'han elaborat amb les peces arqueològiques, les citacions d'inventaris de cada període i la iconografia. La investigació es tanca amb un panorama general corresponent a inicis del segle XVIII, moment d'irrupció de noves modes procedents de Bohèmia i Alemanya, que canviaran l'art del vidre a Europa. / La Historia del vidrio en Mallorca entre los siglos XIV y XVIII está determinada por la importante influencia ejercida por la vidriería catalana y la veneciana. El marco cronológico amplio tiene la finalidad de precisar las continuidades y los cambios producidos en el artesanado. En este sentido, tiene que destacarse como factor fundamental la presencia de vidrieros procedentes de Italia, que sitúan la isla en las dinámicas que caracterizan el arte del vidrio en otros territorios europeos. Para cada época se han situado los principales talleres, las familias de vidrieros y los sistemas de trabajo desarrollados. En relación a los objetos catalogados, hemos constatado la llegada de importaciones islámicas, catalanas y venecianas. Las tipologías se han elaborado con las piezas arqueológicas, las citaciones de inventarios de cada período y la iconografía. La investigación se cierra con un panorama general correspondiente a inicios del siglo XVIII, momento de irrupción de nuevas modas procedentes de Bohemia y Alemania, que cambiaran el arte del vidrio en Europa. / The history of glass in Majorca between the 14th and 18th centuries has been determined by the strong influences exerted by the catalan and venetian glassworks. The wide chronologic framework responds to the intention of specifying the continuities and changes undergone in the craftsmanship. In this sense, it must be highlighted as a fundamental fact the presence of glassmakers coming from Italy, which place the island in the midst of the dynamics characterizing the art of glassmaking. The main glassmakers, families and the working systems developed, have been placed in each period. As for the catalogued pieces, the coming of Islamic, catalan and venetian importations have been stated. Typologies have been stated with archeological pieces, inventory citations for each period and the iconography. The research concludes with a general overview corresponding to the early 18th century, the moment of the arrival of new modes coming from Bohemia and Germany, which would change the art of glass in Europe.