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[pt] É constante o desafio das refinarias de petróleo na busca pela maximização da rentabilidade diante da natureza dinâmica das variáveis que afetam seus processos, como: demanda e especificações de produtos, qualidade de carga e preços de matéria-prima e derivados. Com a expectativa de mudanças nestas variáveis, um planejamento estratégico integrado para definir as necessidades de investimento em novas unidades de processo e ampliação de capacidade de unidades existentes pode contribuir para os melhores resultados do negócio de refino. Em face destas oportunidades e desafios, este trabalho propõe uma análise do planejamento de investimentos em refino, considerando o crescimento da demanda de diesel com ultra baixo teor de enxofre (S10) e também o crescimento plurianual da demanda de derivados, tendo como estudo de caso uma das maiores refinarias brasileiras. Como ferramenta de análise, foi utilizado um modelo matemático para planejamento integrado de refino de petróleo, que considera a otimização do planejamento operacional para definir as necessidades de investimento na refinaria, uma integração temporal, resultando em um modelo não linear inteiro misto (MINLP), cuja resolução utiliza uma lógica de decomposição em dois problemas integrados. Foi analisado o planejamento estratégico de refino, no horizonte de 19 anos e foram feitos vários cenários de demanda, com análises de sensibilidade para preços de petróleo e produtos, limite de importação e restrição de investimentos. Os resultados mostraram alinhamento com situação atual do mercado de derivados, com importação favorecida e com a expectativa de investimento mínimo em refino. / [en] It is a constant challenge for oil refineries the profitability maximization considering the dynamic nature of variables that affect their processes, such as demand and product specifications, feed quality and prices of raw materials and products. Expecting changes in such variables, an integrated strategic planning to define the needs for investment in new process units and capacity expansion of existing units can contribute to better results of the refining business. Given these opportunities and challenges, this dissertation proposes an analysis of refining investment planning, considering the increasing demand for ultralow sulfur diesel (S10) and also the multi-year growth of demand for oil products, performing a case study for one of the largest Brazilian refineries. As an analysis tool, it was used a mathematical model for integrated planning of oil refining, which considers the optimization of operational planning to set the investment needs in the refinery, a temporal integration, resulting in a mixed integer nonlinear model (MINLP), which resolution is based on a logic decomposition in two integrated problems. The strategic refining planning was analyzed on the 19 years horizon for different demand scenarios and some sensitivity analyses were carried out for oil and product prices, import limit and investment restrictions. The results were consistent with the current situation of the Brazilian derivatives market, characterized by favorable import and the minimum investment expected for refining.

Le travail présenté dans cette thèse porte sur le rôle du cortex prémoteur dorsal (PMd) au sujet de la prise de décision (sélection d’une action parmis nombreux choix) et l'orientation visuelle des mouvements du bras. L’ouvrage décrit des expériences électrophysiologiques chez le singe éveillé (Macaca mulatta) permettant d’adresser une fraction importante des prédictions proposées par l'hypothèse des affordances concurrentes (Cisek, 2006; Cisek, 2007a). Cette hypothèse suggère que le choix de toute action est l’issue d'une concurrence entre les représentations internes des exigences et des atouts de chacune des options présentées (affordances; Gibson, 1979). Un intérêt particulier est donné au traitement de l'information spatiale et la valeur des options (expected value, EV) dans la prise de décisions. La première étude (article 1) explore la façon dont PMd reflète ces deux paramètres dans la période délai ainsi que de leur intéraction. La deuxième étude (article 2) explore le mécanisme de décision de façon plus détaillée et étend les résultats au cortex prémoteur ventral (PMv). Cette étude porte également sur la représentation spatiale et l’EV dans une perspective d'apprentissage. Dans un environnement nouveau les paramètres spatiaux des actions semblent être présents en tout temps dans PMd, malgré que la représentation de l’EV apparaît uniquement lorsque les animaux commencent à prendre des décisions éclairées au sujet de la valeur des options disponibles. La troisième étude (article 3) explore la façon dont PMd est impliqué aux “changements d'esprit“ dans un procès de décision. Cette étude décrit comment la sélection d’une action est mise à jour à la suite d'une instruction de mouvement (GO signal). I II Les résultats principaux des études sont reproduits par un modèle computationnel (Cisek, 2006) suggérant que la prise de décision entre plusieurs actions alternatives peux se faire par voie d’un mécanisme de concurrence (biased competition) qui aurait lieu dans la même région qui spécifie les actions. / This thesis examines the role of the dorsal premotor cortex (PMd) in the process of decision making (action selection) and visual guidance of arm movements. The work describes electrophysiological experiments conducted in awake monkeys (Macaca mulatta) and tests a number of important predictions suggested by the affordance competition hypothesis (Cisek, 2006; Cisek, 2007a). This hypothesis suggests that decisions can be viewed as the result of a competition between internal representations of conflicting demands and opportunities for actions or affordances (Gibson, 1979). Specific interest is given to the interaction between spatial information and expected value (EV) in a proposed affordance competition mechanism for action selection. The first study presented (article 1) explores how EV is represented during the delay period in PMd. This study also describes how this area reflects the spatial metrics of the options and examines the interaction between value and spatial information. The second study (article 2) explores the mechanism of action selection in more detail and extends the results to ventral premotor cortex (PMv). This study also addresses the nature of value and spatial representations from a learning perspective. In a novel environment the spatial metrics of the actions seem to be invariably present in PMd, meanwhile EV representations appear only once the animals make behaviorally informed decisions about the value of the available options. The third study (article 3) explores how PMd is involved in “changes of mind” in which action selection is updated following a movement instruction (GO signal). III IV The major findings in all these studies are reproduced by a computational model (Cisek, 2006) suggesting that decisions between actions can be made through a biased competition process that takes place in the same region that specifies the actions.

The Object-Oriented Data Specification Framework (OODSF) is a C++ framework to facilitate programming in a heterogeneous distributed environment. Using the OODSF, C++ language bindings of commonly used specification languages, such as Abstract Syntax Notation 1 (ASN.l) and Interface Definition Language (IDL), can be defined. The OODSF defines C++ class libraries for ASN.l and IDL to simplify the C++ language bindings. Arbitrary application-level IDL and ASN.l specifications can be translated into C++ representations based on these class libraries. The OODSF contains facilities for encoding and decoding transferred data, allowing interoperability in a heterogeneous distributed system. A general interface is provided to encoding and decoding services so that a flexible choice of an encoding rule can be made. The current implementation of the OODSF contains external Encoding Rule (XDR) and Basic Encoding Rule (BER). / Master of Science

This thesis examines the pivotal role of port infrastructure in supporting offshore wind project development, with a focus on the strategic significance of port operation and storage. This study addresses the challenges of evaluating port area demand, complicated by the intricate and dynamic nature of the construction and logistical operations associated with offshore wind development. Through a comprehensive approach that includes a literature review on diverse roles of ports, analysis of port operations for key turbine components, and formulation of an assessment model to estimate port area demand, this research offers insights into the logistical and operational needs of ports in the offshore wind sector. A significant highlight of this study is the consideration of the temporal influence on port demand, a crucial factor stemming from the continuous loading and unloading activities at the port. In addition to port terminal area, hard criteria such as water depth, quay length, and load-bearing capacity are also examined. The findings underscore the connection between port infrastructure and the efficient operation of offshore wind farms. It highlights the need for synchronized coordination between the transport rate of components and offshore installation activities, to meet the specific demands of port infrastructure. Furthermore, the thesis explores these findings in the context of port development, identifying key requirements, challenges, and opportunities within the sector and offering a forward-looking perspective on the industry. This perspective considers the emerging trends, technological advancements, and innovative practices in offshore wind and their implications for port development. In conclusion, the research emphasizes the critical importance of understanding and meeting port specification requirements for the successful execution of offshore wind projects. It calls for continuous research and development efforts to improve the accuracy of estimating port infrastructure enhancement needs, in support of the growing offshore wind industry.

Dans un contexte international, la prévision d'intensité des cyclones tropicaux connaît encore de graves déficiences tandis que la prévision de trajectoire de ces phénomènes météorologiques extrêmes s'est grandement améliorée ces dernières décennies. Une source d'erreur pour la prévision d'intensité est le manque de connaissance des processus physiques qui régissent l'évolution de la structure et de l'intensité des cyclones. Cette thèse, proposée dans le cadre des responsabilités du Centre Météorologique Régional Spécialisé (CMRS) de la Réunion et des axes de recherche du LACy et du CNRM, a pour but d'améliorer la prévision numérique et la compréhension des mécanismes de changement de structure et d'intensité des cyclones dans le sud-ouest de l'océan Indien. On observe statistiquement dans le bassin de fréquents déferlements d'ondes de Rossby qui correspondent à une intrusion des talwegs d'altitude depuis les moyennes latitudes vers les régions où évoluent les cyclones. Ces déferlements advectent dans la troposphère tropicale de l'air d'origine stratosphérique à fort tourbillon potentiel (PV). Le cœur d'un cyclone tropical étant caractérisé par un vortex cyclonique de fort PV, il est donc légitime de se demander si de tels talwegs sont capables de « nourrir » un cyclone en déferlant jusqu'à lui, et l'intensifier par superposition de PV. D'un autre côté, l'approche d'un talweg est associée à d'autres facteurs pouvant jouer en défaveur d'une intensification, comme un fort cisaillement vertical de vent. L'étude de processus est réalisée sur le cyclone Dora (2007) avec le modèle opérationnel du CMRS sur le bassin, Aladin-Réunion. Ce modèle hydrostatique à aire limitée bénéficie d'une résolution horizontale de 8 km et de son propre schéma d'assimilation 3Dvar avec bogus de vent. Un tel bogus permet d'affiner la structure du cyclone à l'instant initial en ajoutant des observations de vent déduites d'un profil analytique et des paramètres de structure du cyclone estimés par les images satellites. Des diagnostiques sur les variables thermodynamiques en sortie de modèle montrent que la phase d'intensification rapide de Dora est bien associée à l'advection de tourbillon potentiel (PV) en provenance du talweg. Bien que fortement cisaillé, le système parvient à s'intensifier grâce à la forte inclinaison du talweg qui advecte du PV au cœur du cyclone en 2 temps et à 2 niveaux (haute et moyenne troposphère). Lorsque le talweg est au plus proche du cyclone, il force un processus dynamique interne appelé « cycle de remplacement du mur de l'œil ». On observe une inclinaison et un renforcement des vitesses verticales à l'extérieur du mur de l'œil principal, associé à une accélération de la circulation cyclonique tangentielle par advection de moment angulaire sur toute l'épaisseur de la troposphère dans cette zone annulaire (mis en évidence par les flux d'Eliassen-Palm). Un second maximum de vent relatif apparaît alors et une deuxième phase d'intensification rapide s'ensuit avec la contraction du mur secondaire. Le forçage de processus internes par une influence externe (un talweg) semble donc être le moteur de l'intensification rapide de Dora dans un environnement cisaillé, et potentiellement celui d'autres cyclones dans le bassin qui sont approchés par des talwegs d'altitude. Les prévisionnistes du CMRS sont invités à surveiller les champs de PV de tels systèmes, en attendant que de plus amples diagnostiques soient réalisés avec l'outil d'inversion du tourbillon potentiel développé sur le modèle global Arpège. / Despite significant improvements in Tropical Cyclone (TC) track forecasts over the past few decades, anticipating the sudden intensity changes of TCs remains a major operational issue. The main purpose of this thesis is to analyze TC rapid intensification processes in relation with external forcing induced by upper-level troughs originating from the mid-latitudes. The impact of initial storm structure on storm evolution and prediction is also documented. An objective definition for rapid intensification in the southwest Indian Ocean is first proposed. The location and frequency of TC-trough interactions are identified, as well as TC-trough arrangements conducive to TC intensification. An interesting study case, TC Dora (2007), is chosen to run numerical simulations initialized with synthetic TC observations blended in a global analysis. The simulated TC-trough interaction is intricate with potential vorticity (PV) advection from the trough into the TC core at mid and upper levels. Vortex intensification first occurs inside the eyewall and results from PV superposition. Further intensification is associated with a subsequent secondary eyewall formation triggered by external forcing from the trough. The numerical model is able to reproduce the main features associated with outer eyewall spin-up, inner eyewall spin-down, and their effects on vortex intensity changes. Another numerical study examines typhoons in the northwest Pacific and demonstrates the critical role played by initial vortex structure in TC track and intensity prediction. Upgrading the initial specification of a TC inner-core structure in numerical models is recommended for future TC prediction improvements.

Diese Dissertation beschäftigt sich mit Methoden zur Behandlung von nicht-ignorierbaren fehlenden Daten und Stichprobenverzerrungen – zwei häufig auftretenden Problemen bei der Analyse von Umfragedaten. Beide Datenprobleme können die Qualität der Analyseergebnisse erheblich beeinträchtigen und zu irreführenden Inferenzen über die Population führen. Daher behandle ich innerhalb von drei verschiedenen Forschungsartikeln, Methoden, die eine Durchführung von sogenannten Sensitivitätsanalysen in Bezug auf Missing- und Selektionsmechanismen ermöglichen und dabei auf typische Survey-Daten angewandt werden können. Im Rahmen des ersten und zweiten Artikels entwickele ich Verfahren zur multiplen Imputation von binären und ordinal Mehrebenen-Daten, welche es zulassen, einen potenziellen Missing Not at Random (MNAR) Mechanismus zu berücksichtigen. In unterschiedlichen Simulationsstudien konnte bestätigt werden, dass die neuen Imputationsmethoden in der Lage sind, in allen betrachteten Szenarien unverzerrte sowie effiziente Schätzungen zuliefern. Zudem konnte ihre Anwendbarkeit auf empirische Daten aufgezeigt werden. Im dritten Artikel untersuche ich ein Maß zur Quantifizierung und Adjustierung von nicht ignorierbaren Stichprobenverzerrungen in Anteilswerten, die auf der Basis von nicht-probabilistischen Daten geschätzt wurden. Es handelt sich hierbei um die erste Anwendung des Index auf eine echte nicht-probabilistische Stichprobe abseits der Forschergruppe, die das Maß entwickelt hat. Zudem leite ich einen allgemeinen Leitfaden für die Verwendung des Index in der Praxis ab und validiere die Fähigkeit des Maßes vorhandene Stichprobenverzerrungen korrekt zu erkennen. Die drei vorgestellten Artikel zeigen, wie wichtig es ist, vorhandene Schätzer auf ihre Robustheit hinsichtlich unterschiedlicher Annahmen über den Missing- und Selektionsmechanismus zu untersuchen, wenn es Hinweise darauf gibt, dass die Ignorierbarkeitsannahme verletzt sein könnte und stellen erste Lösungen zur Umsetzung bereit. / This thesis deals with methods for the appropriate handling of non-ignorable missing data and sample selection, which are two common challenges of survey data analysis. Both issues can dramatically affect the quality of analysis results and lead to misleading inferences about the population. Therefore, in three different research articles, I treat methods for the performance of so-called sensitivity analyses with regards to the missing data and selection mechanism that are usable with typical survey data. In the first and second article, I provide novel procedures for the multiple imputation of binary and ordinal multilevel data that are supposed to be Missing not At Random (MNAR). The methods’ suitability to produce unbiased and efficient estimates could be demonstrated in various simulation studies considering different data scenarios. Moreover, I could show their applicability to empirical data. In the third article, I investigate a measure to quantify and adjust non-ignorable selection bias in proportions estimated based on non-probabilistic data. In doing so, I provide the first application of the suggested index to a real non-probability sample outside its original research group. In addition, I derive general guidelines for its usage in practice, and validate the measure’s performance in properly detecting selection bias. The three presented articles highlight the necessity to assess the sensitivity of estimates towards different assumptions about the missing-data and selection mechanism if it seems realistic that the ignorability assumption might be violated, and provide first solutions to enable such robustness checks for specific data situations.

Research and Development engineering is at the corner stone of humanity’s evolution. It is perceived to be a systematic creative process which ultimately improves the living standard of a society through the creation of new applications and products. The commercial paradigm that governs project selection, resource allocation and market penetration prevails when the focus shifts from pure research to applied research. Furthermore, the road to success through commercialisation is difficult for most inventors, especially in a vast and isolated country such as Australia which is located a long way from wealthy and developed economies. While market leading products are considered unique, the actual process to achieve these products is essentially the same; progressing from an idea, through development to an outcome (if successful). Unfortunately, statistics indicate that only 3% of ‘ideas’ are significantly successful, 4% are moderately successful, and the remainder ‘evaporate’ in that form (Michael Quinn, Chairman, Innovation Capital Associates Pty Ltd). This study demonstrates and analyses two techniques developed by the author which reduce uncertainty in the engineering design and development phase of new product development and therefore increase the probability of a successful outcome. This study expands the existing knowledge of the engineering design and development stage in the new product development process and is couched in the identification of practical methods, which have been successfully used to develop new products by Australian Small Medium Enterprise (SME) Excel Technology Group Pty Ltd (ETG). Process theory is the term most commonly used to describe scientific study that identifies occurrences that result from a specified input state to an output state, thus detailing the process used to achieve an outcome. The thesis identifies relevant material and analyses recognised and established engineering processes utilised in developing new products. The literature identified that case studies are a particularly useful method for supporting problem-solving processes in settings where there are no clear answers or where problems are unstructured, as in New Product Development (NPD). This study describes, defines, and demonstrates the process of new product development within the context of historical product development and a ‘live’ case study associated with an Australian Government START grant awarded to Excel Technology Group in 2004 to assist in the development of an image-based vehicle detection product. This study proposes two techniques which reduce uncertainty and thereby improve the probability of a successful outcome. The first technique provides a predicted project development path or forward engineering plan which transforms the initial ‘fuzzy idea’ into a potential and achievable outcome. This process qualifies the ‘fuzzy idea’ as a potential, rationale or tangible outcome which is within the capability of the organisation. Additionally, this process proposes that a tangible or rationale idea can be deconstructed in reverse engineering process in order to create a forward engineering development plan. A detailed structured forward engineering plan reduces the uncertainty associated with new product development unknowns and therefore contributes to a successful outcome. This is described as the RETRO technique. The study recognises however that this claim requires qualification and proposes a second technique. The second technique proposes that a two dimensional spatial representation which has productivity and consumed resources as its axes, provides an effective means to qualify progress and expediently identify variation from the predicted plan. This spatial representation technique allows a quick response which in itself has a prediction attribute associated with directing the project back onto its predicted path. This process involves a coterminous comparison between the predicted development path and the evolving actual project development path. A consequence of this process is verification of progress or the application of informed, timely and quantified corrective action. This process also identifies the degree of success achieved in the engineering design and development phase of new product development where success is defined as achieving a predicted outcome. This spatial representation technique is referred to as NPD Mapping. The study demonstrates that these are useful techniques which aid SMEs in achieving successful new product outcomes because the technique are easily administered, measure and represent relevant development process related elements and functions, and enable expedient quantified responsive action when the evolving path varies from the predicted path. These techniques go beyond time line representations as represented in GANTT charts and PERT analysis, and represent the base variables of consumed resource and productivity/technical achievement in a manner that facilitates higher level interpretation of time, effort, degree of difficulty, and product complexity in order to facilitate informed decision making. This study presents, describes, analyses and demonstrates an SME focused engineering development technique, developed by the author, that produces a successful new product outcome which begins with a ‘fuzzy idea’ in the mind of the inventor and concludes with a successful new product outcome that is delivered on time and within budget. Further research on a wider range of SME organisations undertaking new product development is recommended.

The present research investigated the challenges and problems facing the public sector institutions regarding the processes, procedures, practices, steps and methods used for human resource recruitment and selection. The South African government outlawed unfair discrimination to promote equality and equity in the labour force. This state of affairs has direct implications for employment practices such as recruitment and selection in the public service. Without a comprehensive recruitment and selection model, public service departments could contravene legislative requirements. As a result, these public service departments then may not succeed in attracting and appointing the best candidates for vacant positions. The intension of this study was to determine the extent to which functions of human resource management (HRM) reflect the spirit and stipulations of the statutory and regulatory framework. These functions include job analysis, job evaluation, job design, job profiles, and human resource planning, as well as induction and orientation. The aim is further to verify to what extent these functions influence recruitment and selection practices. A qualitative research design was used to construct a comprehensive human resource recruitment and selection model. This model is the result of a thorough analysis of comparative recruitment and selection theories, approaches, international best practice, and of existing models. A case study was undertaken within the Department of Justice and Constitutional Development (DOJ&CD). Data was collected by using a questionnaire from a representative sample. The target population comprised senior and middle managers from the National Office in Pretoria and North West Province responsible for human resource functions. They are divided into five sub-clusters. Based on the core findings of this research it was established that the DOJ&CD experiences inefficiencies as far as the following aspects of human resource management are concerned: alignment, development and implementation of appropriate human resource strategies, systems, processes, procedures and methods. This also includes the approaches for recruitment and selection. The DOJ&CD mainly utilises traditional processes of recruitment and selection that do not adequately reflect international best practice and, furthermore, do not adhere to all the stipulations of the myriad forms of legislation that are governing human resources in the public service. A comprehensive model for recruitment and selection was thus of the utmost importance to guide the Department in its recruitment and selection endeavours. The model that is designed as the main contribution of this research is aimed at addressing these challenges. The comprehensive model is intended to guide the DOJ&CD‟s human resource practitioners on recruitment and selection. This is done by means of a processmap and a flow-chart approach. Based on the literature review and empirical study, best practice is proposed that can be associated with each phase or step in the recruitment and selection process. The criteria for the development of the model was based on the theoretical relationship among elements and variables such as strategy, structure, job analysis, job description, job specification and job evaluations, and how these elements are linked to recruitment and selection processes. Such a comprehensive human resource recruitment and selection model can assist practitioners to align all human resource activities and functions within public service departments. This will help to realise their organisational objectives and to operationalise their strategic imperatives successfully. / PhD (Public Management and Governance), North-West University, Potchefstroom Campus, 2014