Individuals utilize heuristics in order to simplify problems, which may lead to biases in decision-making. The research question of this study is: “How does the affect heuristic impact the investment process of private equity decision-makers reviewing proposals?” Through an exploratory multi-case analysis, insight is provided into complex private equity decisions by studying biases in the investment process. This is a study of private equity groups’ (PEG) decision-making process when they consider businesses for investment. Qualitative data was generated from semi-structured interviews with twenty private equity decision-makers. The deliberative heuristics applied in the teaser review are learned from process experience and guide the deliberation on whether to proceed. Simplifying heuristics are applied in the more informal review process. Organizational learning was exhibited as the PEGs have modified their investment structures based on previous experiences. The study indicates that experience and learning lead to the construction of an affect heuristic that subsequently impacts investments. It also confirms the need for strategic decision-makers to recognize their own biases and adjust their processes accordingly. A significant practical implication of this study is the insight provided into the views of the PEG decision-makers as they anticipate the need to supplement the management team is helpful to business owners and their advisors. The study highlights the opportunities for biases in PEG decision-making processes. Accessing decision-makers at larger PEGs and approaching more middle market firms would broaden the results.

In this study, the two-dimensional cutting stock problem (2DCSP) is considered. This is a problem that occurs in the cutting of a number of smaller rectangular pieces or items from a set of large stock rectangles. It is assumed that the set of large objects is sufficient to accommodate all the small items. A heuristic procedure is developed to solve the two-dimensional single stock-size cutting stock problem (2DSSSCSP). This is the special case where the large rectangles are all of the same size. The major objective is to minimize waste and the number of stock sheets utilized. The heuristic procedures developed to solve the 2DSSSCSP are based on the generation of cutting pattern. The Wang algorithm and a specific commercial software package are made use of to generate these patterns. The commercial software was chosen from a set of commercial software packages available in the market. A combinatoric process is applied to generate sets of cutting patterns using the Wang algorithm and the commercial software. The generated cutting patterns are used to formulate an integer linear programming model which is solved using an optimization solver. Empirical experimentation is carried out to test the heuristic procedures using data obtained from both small and real world application problem instances. The results obtained shows that the heuristic procedures developed produce good quality results for both small and real life problem instances. It is quite clear that the heuristic procedure developed to solve the 2DSSSCSP produces cutting patterns which are acceptable in terms of waste generated and may offer useful alternatives to approaches currently available. Broadly stated, this study involves investigating available software (commercial) in order to assess, formulate and investigate methods to attempt to benchmark software systems and algorithms and to employ ways to enhance solutions obtained by using these software systems. / Thesis (M.Sc. (Computer Science))--North-West University, Potchefstroom Campus, 2011.

In this study, we consider the Turkish postal delivery system and develop an effective solution approach for the combined hub location and routing problem where the location of hub nodes are determined, the nonhub regional postal offices are allocated to the hubs, and the optimal set of routes are determined for each hub. Since the realized post-routing distances between origin-destination pairs are different from those used in the hub-location model, we develop an algorithm that finds the route-compatible hub configuration and allocation paths. The algorithm is the one that iterates between the hub-location phase and a routing phase. Our strategy consists of updating the distances used in the first phase in order to produce a solution that contains the cognition of routes. Some special structures in the routed network are also identified and used for improving the solution. Computational experience is reported.

In early 2003, in a major shift in policy, the University of Southern Queensland (USQ) announced that its learning materials would progressively move from a predominantly print-based mode of delivery to a new 'hybrid' mode of delivery across all discipline areas. Central to this delivery would be a resource-rich CDROM containing all study materials, supported with a range of multimedia based enhancements, online support and selective print materials. As this represented a fundamentally new approach to the delivery of materials at USQ, it was essential to ascertain a clear understanding of about the implications of this change for student learning. In implementing this policy it was necessary to establish a range of pedagogically sound, cost effective delivery guidelines, for the development of the course materials and the multimedia based enhancements. In response to this need, this study has developed a set of 10 multimodal design heuristics used to guide the development of these materials. In establishing these guidelines, this thesis contextualises important issues associated with hybrid delivery and considers how catering for a multiliterate clientele by using a combination of multimedia based enhancements in an electronic environment may improve the learning opportunities for students. Two Faculty of Business courses delivered in 2004, ECO2000 'Macroeconomics for Business and Government' and MGT2004 'People Development', were chosen to pilot the new hybrid mode of delivery. The combination of qualitative and quantitative approaches was used to investigate how students have utilised this new environment. This approach rendered a clear indication of student views about the CD based delivery and, more particularly, an appreciation of how they utilised the multimedia based enhancements to augment their studies. Analysis of the research data indicated a strong acceptance of the CD based learning environment. This was particularly true for off-campus and international students. On the whole, students reported a preference for a CD based resource, though this acceptance was moderated by a desire to still receive some print-based materials. Importantly, from this analysis it was possible to add a further four multimodal design heuristics to the original set of ten which informed the design of the multimedia based enhancements for each course. This study demonstrates that higher levels of student engagement are possible when integrating a range of multimedia based enhancements to cater for a range of student learning modalities, whilst also maintaining a balanced environment for more traditional learners1.

Multimodal container terminals are an important part of the logistics systems in international trade. Any improvement in the terminal efficiency is likely to reduce the costs of transporting goods, and to strengthen the trading position of the nation. During the import process, containers flow from ships to the storage yard for temporary storage and then are later moved to the hinterland by rail, or by road. The export process is the reverse of the import process. From the marshalling area, it is possible for a yard machine to carry an inbound container to the storage area and back with an inbound container in one round trip. This thesis investigates the inbound and outbound container process of multimodal container terminals in a multi-ship and multi-berth environment. The aim is to develop mathematical models and analytical tools for yard operation and planning. This study concerns the yardlayout, storage locations, operation strategies as well as the sequencing and scheduling of container process. Several models are developed for the scheduling of container process, taking account of planned and unplanned disruptions, and the intermediate buffer at the marshalling area. The problem is NP-hard and real-life problems often involve large number of containers. In addition, many schedules may not be feasible due to deadlock or violation of precedence-constraints. Good results were achieved on benchmark problems using the proposed innovative. In dealing with unplanned disruptions, reactive scheduling approach was found to give the results similar to as if the disruptions were planned in advance. Numerical investigations are also presented on various factors affecting the efficiency of seaport container terminals including the number of yard machines, and the number of quay crane. As with the various yard-layouts studied, it was found that containers are best stored in rows perpendicular to the quay-line with about 10 to 14 bays in each row. For a shorter ship service time, ideally the containers should be stored as close as possible to the ship. The best storage locations, however, are scarce resources and are not always available. Another model is developed for the best storage location as well as the best schedule for the container process. From an initial best schedule with predefined storage locations, the problem is solved by iterating through the refinement of storage scheme and re-scheduling. At a seaport terminal, ships are planned to arrive and leave within a scheduled time window. Nevertheless, a ship may arrive late due to poor weather conditions or disruptions at the previous port. Such delay may also affect its departure to the subsequent port. To minimise the impact of ship delays, port operators must consider alternate arrangements including re-assignment of berths, re-sequencing of ships and rescheduling of the container process. A ship delay model is developed and the problem is solved by combining branching and Tabu Search. The models developed in this thesis establish the relationship between significant factors and the options for increasing throughput by discovering the bottlenecks. The models are applicable as decision tools for operation planning, yard layout, and cost and benefit analysis for investment in infrastructures.

This thesis explores through the creation of four artworks, the nature of the sublime ruin. To facilitate this it examines the disintegration of selected religious feminine metaphors. The artworks are rendered through a multiplication of layers bound by translucent/transparent resin. These are produced to examine the potentials between traditional craft and contemporary digital mediums, thus creating sites where eroding fragments may express an excess of meaning through enigmatic construction.

This practice-based art and design project explores the potential use of contemporary materials and techniques in relation to extending aesthetic and structural possibilities of embroidery, with a focus on developing textile formations through the medium of ‘free stitch’ machine embroidery. Embroidery is often perceived by the non-enthusiast as a ‘granny craft’: an ‘old’ technique. Contemporary representations of embroidery suggest that new and innovative interpretations exist. Through investigation and experimentation with products, textiles and techniques, the embroidered artefacts that I have crafted are intended to disrupt the conventional perceptions of embroidery by alluding to conceptual associations of tradition and nostalgia. The aim of this project is to promote embroidery as a diverse medium; its use as a means of narrative, a valued skill that spans both art and craft disciplines, and to lift the status of craft by encouraging discourse of craft practice within an academic environment.

The Coalition Structure Generation (CSG) problem requires finding an optimal partition of a set of n agents. An optimal partition means one that maximizes global welfare. Computing an optimal coalition structure is computationally hard especially when there are externalities, i.e., when the worth of a coalition is dependent on the organisation of agents outside the coalition. A number of algorithms were previously proposed to solve the CSG problem but most of these methods were designed for systems without externalities. Very little attention has been paid to finding optimal coalition structures in the presence of externalities, although externalities are a key feature of many real world multiagent systems. Moreover, the existing methods, being non-heuristic, have exponential time complexity which means that they are infeasible for any but systems comprised of a small number of agents. The aim of this research is to develop effective heuristic methods for finding optimal coalition structures in systems with externalities, where time taken to find a solution is more important than the quality of the solution. To this end, four different heuristics methods namely tabu search, simulated annealing, ant colony search and particle swarm optimisation are explored. In particular, neighbourhood operators were devised for the effective exploration of the search space and a compact representation method was formulated for storing details about the multiagent system. Using these, the heuristic methods were devised and their performance was evaluated extensively for a wide range of input data.

O problema de particionamento balanceado de grafos consiste em encontrar uma partição de tamanho k dos vértices de um grafo, minimizando o número de arestas que participam do corte tal que o tamanho de nenhuma parte exceda [en~k], para algum e e > [1, k). Essa dissertação estuda esse problema, apresentando uma revisão recente de heurísticas construtivas, heurísticas de refinamento e técnicas multinível. Também propomos um novo algoritmo híbrido para resolver esse problema de particionamento. Nós mostramos como diversas estratégias para construir e aprimorar partições, assim como algumas novas propostas, podem ser integradas para formar um GRASP com path-relinking. Reportamos experimentos computacionais que mostram que essa abordagem obtém soluções competitivas com particionadores no estado-da-arte. Em particular, o algoritmo híbrido é capaz de encontrar novos melhores valores conhecidos em algumas das menores instâncias, indicando que tem uma contribuição qualitativa comparado aos métodos existentes. / The balanced graph partitioning problem asks to find a k-partition of the vertex set of an undirected graph, which minimizes the total cut size and such that the size of no part exceeds en/k , for some ee > [1, k]. This dissertation studies this problem, providing a recent review of constructive heuristics, refinement heuristics and multilevel techniques. We also propose a new hybrid algorithm for solving this partitioning problem. We show how several good existing strategies for constructing and improving partitions, as well as some newly proposed ones, can be integrated to form a GRASP with path-relinking. We report computational experiments that show that this approach obtains solutions competitive with state-of-the-art partitioners. In particular, the hybrid algorithm is able to find new best known values in some of the smaller instances, indicating that it can make a qualitative contribution compared to existing methods.

O problema de escalonamento num flow shop (ou flow shop scheduling problem, FSSP) é um modelo de sistemas de produção muito comum que é bem estudado na literatura. No entanto, quase toda a literatura foca-se em escalonamentos permutacionais, desconsiderando soluções ótimas e quase ótimas que são escalonamentos não-permutacionais. Além disso, a prática comum padroniza os tempos de processamento de cada operação, mesmo que estes tempos variem dependendo das diferentes capacidades dos operadores das máquinas, cuja diversidade deve ser considerada no processo de escalonamento quando seja significativa, e.g., em centros de emprego para deficientes (CEDs). Nesta tese, propomos métodos para resolver o FSSP não-permutacional, usando o mesmo tempo e esforço que os métodos do estado da arte usam para o FSSP permutacional, e produzindo escalonamentos não-permutacionais com melhor qualidade do que escalonamentos permutacionais e não-permutacionais produzidos por métodos do estado da arte. Também propomos métodos para resolver o problema combinado de designação de trabalhadores heterogêneos e escalonamento de tarefas num flow shop (ou heterogeneous workforce assignment and flow shop scheduling problem, Het-FSSP), produzindo soluções que compensam as diferentes capacidades e deficiências dos trabalhadores com pequenas perdas nos objetivos da produção. Além do mais, a designação de trabalhadores heterogêneos pode ser integrada em outros problemas de escalonamento, como fizemos com o problema combinado de designação de trabalhadores heterogêneos e escalonamento de tarefas num job shop (ou heterogeneous workforce assignment and job shop scheduling problem, Het-JSSP). / The flow shop scheduling problem (or FSSP) is a very common model of production systems that is well studied in the literature. However, almost all the literature focuses on the permutation FSSP, disregarding optimal and near optimal solutions that are non-permutation schedules. Besides, common practice standardizes the processing times of each operation, even when those times may vary depending on different capabilities of the machine operators, whose diversity must be considered in the scheduling process when it is significant, e.g., in Sheltered Work centers for Disabled (SWDs). In this thesis, we propose methods to solve the non-permutation FSSP, using the same time and effort as state-of-the-art methods for the permutation FSSP, and producing non-permutation schedules with better quality than permutation and non-permutation schedules produced by state-of-the-art methods. We also propose methods to solve the combined heterogeneous workforce assignment and flow shop scheduling problem (or Het-FSSP), producing solutions that compensate the different capabilities and disabilities of the workers with minor or null losses in the productivity objectives. Moreover, the heterogeneous workforce assignment may be integrated into other shop scheduling models, as we did with the heterogeneous workforce assignment and job shop scheduling problem (or Het-JSSP) with similar results.