Conventionally, the focus during supplier evaluation has been to assess cost, quality and delivery effectiveness due to their impact on profitability. In recent years, there has been increased emphasis on promoting more sustainable business practices that focus on reducing environmental impact and improve societal well-being, in addition to economic benefits. However, most of the existing supplier evaluation methods in literature as well as those used by leading companies fall short of comprehensively assessing suppliers from a Triple Bottom Line (TBL) perspective. TBL defined as holistically looking at the economic, environmental, and societal aspects of an entity. This paper presents a review and selection of metrics for economic, environmental and societal sustainability evaluation. In addition, this work proposes a methodology for combining the scores into a comprehensive score that can be used to compare two entities performance relative to the TBL.

Entrepreneurs are found globally in all industries. In the tourism industry, entrepreneurs feature strongly in the events sector. The purpose of this study is to determine the entrepreneurs' role at festivals and in this case a national arts festival. The literature revealed that this type of study has not previously been conducted in South Africa. The literature review indicates that arts festivals as income generating events can be seen as an entrepreneurial opportunity to maximise economic activity. Entrepreneurs play a vital role in the success of an event such as arts festival. Entrepreneurs initiate transformation and serve as catalysts of innovation. Entrepreneurs are important role players since they attract and retain visitors and contribute to forming cultural identity of the arts festival. In order to achieve the objective, a survey of all small businesses that were trading at one of South Africa's largest arts festivals, namely the Aardklop National Arts Festival held annually in the city of Potchefstroom, was conducted. Two hundred and twenty two useable questionnaires were captured on Excel and the data analysis included a factor analysis and descriptive results. The questionnaire consisted of three sections: section A - demographical information - 7 questions; section B - information on the business - 8 questions; and section C - festival information - 6 questions. The main results reveal that the most important characteristics contributing to entrepreneurship are: a need for achievement, being successful, having the necessary organising skills, self-edification, being explorative, and commitment. The entrepreneurs indicated that they perceive their role at the arts festival to deliver unique, quality products and services and to market their businesses. The findings from this study contributes to the limited academic research on entrepreneurs at arts festivals and will be beneficial for arts festival organising committees to determine future strategies on including entrepreneurs at arts festivals. / Thesis (M.Com. (Tourism))--North-West University, Potchefstroom Campus, 2010.

Entrepreneurs are found globally in all industries. In the tourism industry, entrepreneurs feature strongly in the events sector. The purpose of this study is to determine the entrepreneurs' role at festivals and in this case a national arts festival. The literature revealed that this type of study has not previously been conducted in South Africa. The literature review indicates that arts festivals as income generating events can be seen as an entrepreneurial opportunity to maximise economic activity. Entrepreneurs play a vital role in the success of an event such as arts festival. Entrepreneurs initiate transformation and serve as catalysts of innovation. Entrepreneurs are important role players since they attract and retain visitors and contribute to forming cultural identity of the arts festival. In order to achieve the objective, a survey of all small businesses that were trading at one of South Africa's largest arts festivals, namely the Aardklop National Arts Festival held annually in the city of Potchefstroom, was conducted. Two hundred and twenty two useable questionnaires were captured on Excel and the data analysis included a factor analysis and descriptive results. The questionnaire consisted of three sections: section A - demographical information - 7 questions; section B - information on the business - 8 questions; and section C - festival information - 6 questions. The main results reveal that the most important characteristics contributing to entrepreneurship are: a need for achievement, being successful, having the necessary organising skills, self-edification, being explorative, and commitment. The entrepreneurs indicated that they perceive their role at the arts festival to deliver unique, quality products and services and to market their businesses. The findings from this study contributes to the limited academic research on entrepreneurs at arts festivals and will be beneficial for arts festival organising committees to determine future strategies on including entrepreneurs at arts festivals. / Thesis (M.Com. (Tourism))--North-West University, Potchefstroom Campus, 2010.

Pastatų atnaujinimas (modernizavimas) yra viena iš prioritetinių ES sanglaudos politikos sričių. Augančios energinių išteklių kainos bei higienos normų netenkinanti gyvenamoji, darbo ir poilsio aplinka skatina visuomenę labiau domėtis ir aktyviau dalyvauti pastatų atnaujinimo procese. Disertacijos tikslas – sukurti teorinį pastatų atnaujinimo efektyvumo vertinimo modelį, pagrįstą daugiatiksliais sprendimo priėmimo metodais, bei jį praktiškai pritaikyti naudojant visuomeninės paskirties pastatų tyrimų, atliktų prieš ir po atnaujinimo, rezultatus. Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, literatūros ir šaltinių bei autoriaus publikacijų disertacijos tema sąrašai, santrauka anglų kalba ir trys priedai. Įvade formuluojama problema, aprašomas darbo aktualumas, tyrimų objektas, įvardijamas darbo tikslas bei uždaviniai, pateikiama tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos ir pranešimai konferencijose bei pateikiama disertacijos struktūra. Pirmasis skyrius yra skirtas literatūros (mokslinių publikacijų ir teisės aktų) analizei. Jame pateiktas statinių klasifikavimas pagal paskirtį ir pastatų atnaujinimą lemiantys veiksniai, atlikta visuomeninės paskirties pastatų atnaujinimo analizė, pateikta daugiatikslio sprendimo priėmimo sąvoka ir daugiatikslių sprendimo priėmimo metodų klasifikacija, aprašytas daugiatikslių metodų pritaikymas... [toliau žr. visą tekstą] / Renovation (modernisation) of buildings is one of the priority areas of EU cohesion policy. Growing prices for energy resources as well as living, working and leisure environments that do not conform to requirements of hygiene norms encourage the public to take more efforts towards participation in the process of building renovation. The dissertation aim to create a theoretical model for the assessment of efficiency of building renovation based on multi-attribute decision making methods and use it in practice with results of investigations made on public buildings (kindergartens) before and after renovation. The dissertation comprises an introduction, three chapters, general conclusions, lists of literature, resources and publications of the author on the topic of the dissertation, abstract in English and three annexes. The introduction specifies the problem, describes the relevance of the paper, the research object, aim and objectives as well as methodology of the research, its novelty, practical significance of results, and defended statements. Finally, it lists publications and conference presentations produced by the author on the topic of the dissertation and presents its structure. Chapter one is dedicated for literature (scientific publications and legislative acts) analysis. It provides classification of structures according to their intended use and lists factors determining renovation of buildings; describes the analysis into renovation of public buildings; presents... [to full text]

Securing information systems from cyber attacks, malware and internal cyber threats is a difficult problem. Attacks on authentication and authorization (access control) is one of the more predominant and potentially rewarding attacks on distributed architectures. Attribute-Based Access Control (ABAC) is one of the more recent mechanisms to provide access control capabilities. ABAC combines the strength of cryptography with semantic expressions and relational assertions. By this composition, a powerful grammar is devised that can not only define complex and scalable access control policies, but defend against attacks on the policy itself. This thesis demonstrates how ABAC can be used as a primary access control solution for enterprise and commercial applications. / Graduate / 0984 / djbchepe@gmail.com

In recent years, two distributed system technologies have emerged: Peer-to-Peer (P2P) and cloud computing. For the former, the computers at the edge of networks share their resources, i.e., computing power, data, and network bandwidth, and obtain resources from other peers in the same community. Although this technology enables efficiency, scalability, and availability at low cost of ownership and maintenance, peers defined as ``like each other'' are not wholly controlled by one another or by the same authority. In addition, resources and functionality in P2P systems depend on peer contribution, i.e., storing, computing, routing, etc. These specific aspects raise security concerns and attacks that many researchers try to address. Most solutions proposed by researchers rely on public-key certificates from an external Certificate Authority (CA) or a centralized Public Key Infrastructure (PKI). However, both CA and PKI are contradictory to fully decentralized P2P systems that are self-organizing and infrastructureless. To avoid this contradiction, this thesis concerns the provisioning of public-key certificates in P2P communities, which is a crucial foundation for securing P2P functionalities and applications. We create a framework, named the Self-Organizing and Self-Healing CA group (SOHCG), that can provide certificates without a centralized Trusted Third Party (TTP). In our framework, a CA group is initialized in a Content Addressable Network (CAN) by trusted bootstrap nodes and then grows to a mature state by itself. Based on our group management policies and predefined parameters, the membership in a CA group is dynamic and has a uniform distribution over the P2P community; the size of a CA group is kept to a level that balances performance and acceptable security. The muticast group over an underlying CA group is constructed to reduce communication and computation overhead from collaboration among CA members. To maintain the quality of the CA group, the honest majority of members is maintained by a Byzantine agreement algorithm, and all shares are refreshed gradually and continuously. Our CA framework has been designed to meet all design goals, being self-organizing, self-healing, scalable, resilient, and efficient. A security analysis shows that the framework enables key registration and certificate issue with resistance to external attacks, i.e., node impersonation, man-in-the-middle (MITM), Sybil, and a specific form of DoS, as well as internal attacks, i.e., CA functionality interference and CA group subversion. Cloud computing is the most recent evolution of distributed systems that enable shared resources like P2P systems. Unlike P2P systems, cloud entities are asymmetric in roles like client-server models, i.e., end-users collaborate with Cloud Service Providers (CSPs) through Web interfaces or Web portals. Cloud computing is a combination of technologies, e.g., SOA services, virtualization, grid computing, clustering, P2P overlay networks, management automation, and the Internet, etc. With these technologies, cloud computing can deliver services with specific properties: on-demand self-service, broad network access, resource pooling, rapid elasticity, measured services. However, theses core technologies have their own intrinsic vulnerabilities, so they induce specific attacks to cloud computing. Furthermore, since public clouds are a form of outsourcing, the security of users' resources must rely on CSPs' administration. This situation raises two crucial security concerns for users: locking data into a single CSP and losing control of resources. Providing inter-operations between Application Service Providers (ASPs) and untrusted cloud storage is a countermeasure that can protect users from lock-in with a vendor and losing control of their data. To meet the above challenge, this thesis proposed a new authorization scheme, named OAuth and ABE based authorization (AAuth), that is built on the OAuth standard and leverages Ciphertext-Policy Attribute Based Encryption (CP-ABE) and ElGamal-like masks to construct ABE-based tokens. The ABE-tokens can facilitate a user-centric approach, end-to-end encryption and end-to-end authorization in semi-trusted clouds. With these facilities, owners can take control of their data resting in semi-untrusted clouds and safely use services from unknown ASPs. To this end, our scheme divides the attribute universe into two disjointed sets: confined attributes defined by owners to limit the lifetime and scope of tokens and descriptive attributes defined by authority(s) to certify the characteristic of ASPs. Security analysis shows that AAuth maintains the same security level as the original CP-ABE scheme and protects users from exposing their credentials to ASP, as OAuth does. Moreover, AAuth can resist both external and internal attacks, including untrusted cloud storage. Since most cryptographic functions are delegated from owners to CSPs, AAuth gains computing power from clouds. In our extensive simulation, AAuth's greater overhead was balanced by greater security than OAuth's. Furthermore, our scheme works seamlessly with storage providers by retaining the providers' APIs in the usual way.

As more and more remotely sensed data becomes available it is becoming increasingly harder to analyse it with the more traditional labour intensive, manual methods. The commonly used techniques, that involve expert evaluation, are widely acknowledged as providing inconsistent results, at best. We need more general techniques that can adapt to a given situation and that incorporate the strengths of the traditional methods, human operators and new technologies. The difficulty in interpreting remotely sensed data is that often only a small amount of data is available for classification. It can be noisy, incomplete or contain irrelevant information. Given that the training data may be limited we demonstrate a variety of techniques for highlighting information in the available data and how to select the most relevant information for a given classification task. We show that more consistent results between the training data and an entire image can be obtained, and how misclassification errors can be reduced. Specifically, a new technique for attribute selection in neural networks is demonstrated. Machine learning techniques, in particular, provide us with a means of automating classification using training data from a variety of data sources, including remotely sensed data and expert knowledge. A classification framework is presented in this thesis that can be used with any classifier and any available data. While this was developed in the context of vegetation mapping from remotely sensed data using machine learning classifiers, it is a general technique that can be applied to any domain. The emphasis of the applicability for this framework being domains that have inadequate training data available.

Thesis (MScEng (Industrial Engineering))--Stellenbosch University, 2008. / Passenger cars are either imported to or assembled in South Africa, and then distributed to the customer. An important part of the supply chain is formed by the auto carrier companies who do this distribution. The basis of this thesis is a study that was executed in collaboration with a South African auto carrier company, and the objective was to improve the long-distance auto carrier fleet management through improved tactical operational policies. These policies focus on application of the fleet by assigning transportation vehicles to routes, as well as the business rules that must be followed at pick-up and drop-off locations. Several rules were developed during this study, which, together with specific transportation vehicle (carriers) assignments, form operational scenarios. The quality of each scenario was evaluated using discrete event simulation over a six month time-span, and considering four decision parameters simultaneously. These parameters are 1) useful kilometres travelled by the long-distance carriers, 2) empty kilometres travelled by the same long-distance carriers, 3) the expected number of cars waiting to be transported and 4) the expected time it takes to deliver a car to its destination. A high level of uncertainty prevails in these transportation operations, while fluctuating demand calls for the dynamic allocation and management of carriers in order to sustain an acceptable service level in a cost-effective manner. The best tactical policies should maximize the number of cars delivered on time at the lowest cost. Major constraints considered are staff- and maintenance schedules. While searching for the best of several scenarios, multiple, conflicting criteria had to be evaluated, as mentioned above. Two multi-criteria decision analysis (MCDA) methods were used namely SAW and TOPSIS, while the Mahalanobis distance method was also applied as an evaluation technique. These methods were used to rank scenarios. Additionally, the application of Portfolio theory and the efficient frontier was investigated for applicability to the problem studied. An analogy to the efficient frontier providing an additional means for scenario selection and evaluation was developed. The result of this study provides the decision maker of the auto carrier company with a tactical decision aid, consisting of the MCDA and Mahalanobis scenario rankings, a cost-benefit graph and a fleet portfolio efficient frontier, to aid long-distance carrier management. Additionally, a sensitivity analysis was also done for strategic planning concerned with the sufficient long-distance carrier fleet size. The first part of this thesis comprises a study of literature in which freight operations, auto carrier studies and the auto carrier context in South Africa are investigated. The problem is formulated and a suitable formulation and solution tool identified. Multi-criteria decision analysis is also investigated in order to enable scenario evaluation. The solution development phase consisted of the simulation model concept development, acquisition of input data, model verification and validation, scenario construction, simulation execution, and analysis of results.

Uma interface com o usuário é composta por duas "vias" de comunicação, uma que vai do usuário até o sistema e outra que vai do sistema até o usuário. Cada uma destas "vias" possui um formalismo que define a comunicação associado. Neste trabalho, estes formalismos são descritos com uma gramática de atributos. Esta gramática foi expandida de forma a permitir a definição dos elementos que compõe a interface do usuário, e da estrutura que irá controlar a seqüência de execução das tarefas oferecidas pelos sistemas de aplicação. Ao longo do trabalho são discutidas algumas técnicas de descrição do formalismo de comunicação entre interface e sistema, são abordados os estilos de interação e apresentada as expansões aplicadas sobre gramáticas de atributos. Um exemplo auxilia a compreensão do uso da linguagem proposta, e um protótipo permite a validação das definições. / A user interface is composed by two "ways" of communication, one from the user to the system and the other linking the system to the user. Each of these "ways" has it's own mechanism. In this work, these mechanisms are described through an attribute grammar. This grammar has been expanded to allow the definition of the structure of the interface elements and the control of the execution of the tasks that the application system implements. Through this work, technics that describe the communication between the interface and the system, interaction styles and the extensions made on attribute grammar are discussed. An example is given to explain the use of the proposed mechanism and a prototype validates ideas discussed.

Esta pesquisa terá como objetivo compreender a tese do monismo, isto é, a tese de que existe uma única substância cuja unidade é garantida pela compatibilidade entre sua natureza absolutamente infinita e a multiplicidade real dos seus infinitos atributos. Mas o monismo não é aceito por todos os intérpretes como não problemático, o que, se comprovado, levaria o sistema de Espinosa à ruína. No primeiro capítulo, através da crítica de um destes intérpretes, Ferdinand Alquié, será colocado o problema do monismo. De acordo com este intérprete, Espinosa não consegue estabelecer racionalmente a possibilidade da substância absoluta. Veremos que, não conseguindo conceber como os infinitos atributos podem constituir a essência de uma substância que seja única, Alquié conclui que a tese do monismo é incompatível com a estrutura argumentativa do primeiro livro da Ética. Após a exposição do problema do monismo apresentado a partir de Alquié, será realizada uma tentativa de resgatar a coerência interna da obra de Espinosa. Este estudo visará explicitar os conceitos de substância e atributo, procurando acompanhar as duas etapas da construção do monismo ao longo das onze primeiras proposições da Ética, a saber: (1) a prova de que há uma única substância por atributo; (2) a prova de que há uma única substância para todos os atributos. Para avançar na compreensão dos problemas ontológicos envolvidos na construção do monismo, e de como a posição de Espinosa só pode ser compreendida a partir de uma transformação profunda dos conceitos herdados do cartesianismo, a pesquisa privilegiará as interpretações magistrais propostas por Martial Gueroult (Spinoza, I, Dieu; Aubier-Montaigne, Paris, 1968) e Gilles Deleuze (Spinoza et le problème de l'expression; Les Editions de Minuit, Paris, 1968). Estes intérpretes realizam cada um ao seu modo uma genealogia da substância absolutamente infinita e apresentam soluções que permitem pensar a tese do monismo como coerente. Estas soluções serão apresentadas e avaliadas para que se saiba em que medida elas conseguem expor o problema do monismo e solucioná-lo de maneira plausível. / This work has the purpose to comprehend the monisms thesis, i.e. the thesis that only one substance exists which unity is secured by the compatibility between its absolute and infinite nature, and the real multiplicity of its infinite attributes. But the monism is not accepted as not problematic by all the interpreters, which, if confirmed, would lead Spinozas system to ruin. In the first chapter, the monisms problem will be presented through the critic of one of those interpreters, Ferdinand Alquié. According to him, Spinoza cannot establish, rationally, the possibility of the absolute substance. We will see that, Alquié, not being able to conceive how the infinite attributes can constitute the essence of a substance that is unique, concludes that the monisms thesis is incompatible with the argumentative structure of the first book of the Ethic. After the explanation of the monisms problem, presented from Alquié, we will try to recover the internal coherence of Spinozas work. This study aim to make explicit the concepts of substance and attribute, looking to follow the two stages of the monisms construction along the first eleven propositions of the Ethic, that is: (1) the proof that exists one unique substance per attribute; (2) the proof that exists only one substance for all attributes. To advance in the ontological problems involved in the monisms construction, and how Spinozas position can only be comprehended through a profound transformation of the concepts inherited by the cartesianism, the research will favour the masterly interpretations propounded by Martial Gueroult (Spinoza, I, Dieu; Aubier-Montaigne, Paris, 1968) and Gilles Deleuze (Spinoza et le problème de l'expression; Les Editions de Minuit, Paris, 1968). These interpreters carry out each in its own fashion a genealogy of the absolutely infinite substance and present solutions that allow us to think the monism as coherent. Such solutions will be presented and evaluated, aiming to know to what extent they can show the problem of the monism and solve it in a plausible way.