The increasing number of reports on data leakage incidents increasingly erodes the already low consumer confidence in cloud services. Hence, some organisations are still hesitant to fully trust the cloud with their confidential data. Therefore, this study raises a critical and challenging research question: How can we restore the damaged consumer confidence and improve the uptake and security of cloud services? This study makes a plausible attempt at unpacking and answering the research question in order to holistically address the data leakage problem from three fronts, i.e. conflict-aware virtual machine (VM) placement, strong authentication and digital forensic readiness. Consequently, this study investigates, designs and develops an innovative conceptual architecture that integrates conflict-aware VM placement, cutting-edge authentication and digital forensic readiness to strengthen cloud security and address the data leakage problem in the hope of eventually restoring consumer confidence in cloud services. The study proposes and presents a conflict-aware VM placement model. This model uses varying degrees of conflict tolerance levels, the construct of sphere of conflict and sphere of non-conflict. These are used to provide the physical separation of VMs belonging to conflicting tenants that share the same cloud infrastructure. The model assists the cloud service provider to make informed VM placement decisions that factor in their tenants’ security profile and balance it against the relevant cost constraints and risk appetite. The study also proposes and presents a strong risk-based multi-factor authentication mechanism that scales up and down, based on threat levels or risks posed on the system. This ensures that users are authenticated using the right combination of access credentials according to the risk they pose. This also ensures end-to-end security of authentication data, both at rest and in transit, using an innovative cryptography system and steganography. Furthermore, the study proposes and presents a three-tier digital forensic process model that proactively collects and preserves digital evidence in anticipation of a legal lawsuit or policy breach investigation. This model aims to reduce the time it takes to conduct an investigation in the cloud. Moreover, the three-tier digital forensic readiness process model collects all user activity in a forensically sound manner and notifies investigators of potential security incidents before they occur. The current study also evaluates the effectiveness and efficiency of the proposed solution in addressing the data leakage problem. The results of the conflict-aware VM placement model are derived from simulated and real cloud environments. In both cases, the results show that the conflict-aware VM placement model is well suited to provide the necessary physical isolation of VM instances that belong to conflicting tenants in order to prevent data leakage threats. However, this comes with a performance cost in the sense that higher conflict tolerance levels on bigger VMs take more time to be placed, compared to smaller VM instances with low conflict tolerance levels. From the risk-based multifactor authentication point of view, the results reflect that the proposed solution is effective and to a certain extent also efficient in preventing unauthorised users, armed with legitimate credentials, from gaining access to systems that they are not authorised to access. The results also demonstrate the uniqueness of the approach in that even minor deviations from the norm are correctly classified as anomalies. Lastly, the results reflect that the proposed 3-tier digital forensic readiness process model is effective in the collection and storage of potential digital evidence. This is done in a forensically sound manner and stands to significantly improve the turnaround time of a digital forensic investigation process. Although the classification of incidents may not be perfect, this can be improved with time and is considered part of the future work suggested by the researcher. / Thesis (PhD)--University of Pretoria, 2020. / Computer Science / PhD / Unrestricted

Det transformativa ledarskapet anses vara ett idealt ledarskap i dagens samhälle där egenskaper såsom lyhördhet och individuell motivering hos medarbetarna uppskattas hos många. Studier har tidigare gjorts avseende vilken personlighet ledare med olika ledarskapsattribut besitter, men färre studier har fokuserat på det önskade ledarskapet ur medarbetarnas perspektiv. Därför var syftet med denna studie att undersöka om det fanns ett samband mellan personlighetsegenskapen extraversion och önskat transformativt ledarskap hos medarbetarna på teminalanläggningarna inom ett medelstort svenskt rederi inom färjetrafiken. Datat samlades in genom en digital undersökningsenkät. Undersökningen sträckte sig över samtliga tre hamnterminaler där totalt 72 personer deltog. Resultatet visade att det inte fanns något signifikant samband mellan önskat transformativt ledarskap och extraversion inom de aktuella anläggningarna. Slutsatsen drogs att andra personlighetsdimensioner inte kan uteslutas som betydelse för att forma ett önskat ledarskapsbeteende, och att variablernas resultat separat trots avsaknaden av samband kan vara värdefullt för företagets verksamheter.

A determinação do valor das empresas é o fator chave nas negociações de fusões e aquisições e tem por objetivo estimar uma faixa de referência que sirva como base nas negociações de tais empresas. A avaliação também é fundamental na determinação do valor de mercado das empresas. As metodologias de Fluxo de Caixa Descontado (FCD) e de múltiplos são as principais formas de se avaliar empresas. A abordagem por múltiplos baseia-se no princípio de que ativos e empresas semelhantes deveriam ter preços e múltiplos semelhantes. Os múltiplos obtidos de empresas semelhantes são aplicados aos respectivos parâmetros da empresa avaliada, dando como resultado o “valor de referência da empresa." Entretanto as empresas comparáveis precisam apresentar fundamentos e características semelhantes. Como a regressão permite o controle das diferenças entre as variáveis que fazem os múltiplos variar de uma empresa para outra, não seria necessário limitar a procura por empresas comparáveis apenas ao setor da empresa avaliada. Desta forma, esta dissertação tem por objetivo desenvolver um modelo de estimação relativa baseada em indicadores contábeis do valor das empresas não financeiras negociadas nas principais bolsas de valores do mundo. A parte empírica desta dissertação tem por objetivo identificar quais indicadores contábeis são direcionadores de valor, ou seja, os que estão fortemente correlacionados com o valor das empresas e avaliar as relevâncias que estes indicadores assumem em bolsas e setores diferentes. / The main methodologies to value companies are Discounted Cash Flow and Relative Valuation (multiples). In relative valuation, the value of an asset is compared to the values assessed by the market for similar or comparable assets. The obtained multiple of a comparable firm, like Firm Value/EBITDA, is applied to the same parameter of the company being valued, resulting in its relative value. Otherwise, comparable companies need to have similar fundamentals and characteristics. The question of how to control for these differences, when comparing a multiple across several firms, becomes a key one. The multiple regressions can control the differences between the variables that make multiples change company by company. With the multiple regressions it would not be necessary to limit the choice of comparable companies to the one from the same sector of the company being valued. This study aims to develop a valuation model based on accounting indicators to estimate the Firm Value of listed companies of the main stock exchanges of the world. The main goal of this dissertation is to identify what accounting indicators are value drivers (that are strongly correlated with the Firm Value) and determine the relevance that these indicators have in different countries and sectors.

A method to detect relationships between disease susceptibility and multilocus genetic interactions is the Multifactor-Dimensionality Reduction (MDR) technique pioneered by Ritchie et al. (2001). Since its introduction, many extensions have been pursued to deal with non-binary outcomes and/or account for multiple interactions simultaneously. Studying the effects of multilocus genetic interactions on continuous traits (blood pressure, weight, etc.) is one case that MDR does not handle. Culverhouse et al. (2004) and Gui et al. (2013) proposed two different methods to analyze such a case. In their research, Gui et al. (2013) introduced the Quantitative Multifactor-Dimensionality Reduction (QMDR) that uses the overall average of response variable to classify individuals into risk groups. The classification mechanism may not be efficient under some circumstances, especially when the overall mean is close to some multilocus means. To address such difficulties, we propose a new algorithm, the Ordered Combinatorial Quantitative Multifactor-Dimensionality Reduction (OQMDR), that uses a series of testings, based on ascending order of multilocus means, to identify best interactions of different orders with risk patterns that minimize the prediction error. Ten-fold cross-validation is used to choose from among the resulting models. Regular permutations testings are used to assess the significance of the selected model. The assessment procedure is also modified by utilizing the Generalized Extreme-Value distribution to enhance the efficiency of the evaluation process. We presented results from a simulation study to illustrate the performance of the algorithm. The proposed algorithm is also applied to a genetic data set associated with Alzheimer's Disease.

Thailand is entering into a new phase of educational administration under the new National Education Act of 1999 which requires all educational institutions to have internal and external quality assurance in order to ensure improvement of educational quality and standards at all levels (Section 47). This means that all educational institutions, especially in the private sector, have to undergo many changes, including changes in administration, teaching and learning processes, methods of evaluation and professional development programs. The current study focused specifically on the transformational leadership behaviour of principals on school culture. Culture is considered to be a key factor in determining whether school improvement is possible (Deal & Peterson, 1999). The study was conducted in two phases: quantitative and a qualitative, and carried out in the secondary schools of the Brothers of St. Gabriel, in Thailand. In the quantitative phase, the researcher used two instruments, namely the Multifactor Leadership Questionnaire (MLQ, Short form) developed by Bass (2000) to measure the leadership behaviour of principals, and the School Culture Survey developed by Gruenert (1998) to measure school culture. The results from the quantitative study were used to select a school for the second phase of the study that was carried out using a qualitative approach. The quantitative findings provided descriptive evidence that transformational leadership existed in the schools of the Brothers of St. Gabriel, in Thailand and the dominant culture of the Gabrieltie schools was Professional Development. In addition, the findings also revealed that there was a significant relationship between leadership behaviour and school culture. In the second phase, the leadership behaviour of the selected principal was interpreted based on transformational leadership applied in a school setting. This process was outlined by Leithwood (1996) as frame of reference to identify a pattern of leadership behaviour of the selected principal. The findings revealed that the selected principal exercised the qualities of transformational leadership to some extent. Some qualities were missing and some were practised to a moderate degree. The study helps provide guidance and direction to principals who wish to exercise their leadership in a more appropriate and relevant way particularly in a context of change.

This research investigated the leadership style in a research and development (R&D) work unit within a petro-chemical company, using the Full Range Leadership Development Theory as assessed by Multifactor-Leadership-Questionnaire (MLQ). From the literature review conducted, it was concluded that an R&D environment is multi-dimensional and the workforce can be diverse in the field of specialisation and personality characteristics. Subsequently, the literature review also focused on functional diversity and gender differences within technological and/or scientific environments. Descriptive statistics were provided and the data were then statistically analysed. The research results showed a statistical difference in the perception of the frequency of leadership style between manager-leaders and subordinates. Differences in the mean scores of manager-leaders and subordinates found that the manager-leaders overestimated the frequency ratings of their transformational leadership style and the leadership outcomes, while they under-estimated the frequency ratings for transactional and laissez-faire leadership style. This indicates that although the manager-leaders consider themselves as more transformational, the subordinates of this R&D unit view their immediate managers as not displaying ideal levels of transformational leadership behaviours. A self-bias phenomenon may be present where the manager-leaders judge themselves as overly favourable. It is recommended that this be addressed within the organisation. A statistical significant difference was observed in how some male and female employees experienced their manager-leaders' leadership style. The females indicated a higher frequency of laissez-faire leadership style, while some males viewed their manager-leaders as more transformational compared to the female employees. Manager-leaders may need different skills to manage females and in general an increasing awareness of gender bias within the unit may mitigate stereotypical assumptions. No statistically significant differences (p<0, 05) could be found for the total group between functional areas, being scientists versus engineers. It should be noted that the departments consist of predominantly scientists, while only one department showed a mixture of scientists and engineers. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.

This research investigated the leadership style in a research and development (R&D) work unit within a petro-chemical company, using the Full Range Leadership Development Theory as assessed by Multifactor-Leadership-Questionnaire (MLQ). From the literature review conducted, it was concluded that an R&D environment is multi-dimensional and the workforce can be diverse in the field of specialisation and personality characteristics. Subsequently, the literature review also focused on functional diversity and gender differences within technological and/or scientific environments. Descriptive statistics were provided and the data were then statistically analysed. The research results showed a statistical difference in the perception of the frequency of leadership style between manager-leaders and subordinates. Differences in the mean scores of manager-leaders and subordinates found that the manager-leaders overestimated the frequency ratings of their transformational leadership style and the leadership outcomes, while they under-estimated the frequency ratings for transactional and laissez-faire leadership style. This indicates that although the manager-leaders consider themselves as more transformational, the subordinates of this R&D unit view their immediate managers as not displaying ideal levels of transformational leadership behaviours. A self-bias phenomenon may be present where the manager-leaders judge themselves as overly favourable. It is recommended that this be addressed within the organisation. A statistical significant difference was observed in how some male and female employees experienced their manager-leaders' leadership style. The females indicated a higher frequency of laissez-faire leadership style, while some males viewed their manager-leaders as more transformational compared to the female employees. Manager-leaders may need different skills to manage females and in general an increasing awareness of gender bias within the unit may mitigate stereotypical assumptions. No statistically significant differences (p<0, 05) could be found for the total group between functional areas, being scientists versus engineers. It should be noted that the departments consist of predominantly scientists, while only one department showed a mixture of scientists and engineers. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2010.

Submitted by MFEE Mestrado Profissional em Finanças e Economia Empresarial da EPGE (mfee@fgv.br) on 2015-02-24T19:56:53Z No. of bitstreams: 1 TESE FINAL Débora.pdf: 3098662 bytes, checksum: 2c28fd9275298b66bf5b3a7405f356d9 (MD5) / Approved for entry into archive by GILSON ROCHA MIRANDA (gilson.miranda@fgv.br) on 2015-03-25T20:32:36Z (GMT) No. of bitstreams: 1 TESE FINAL Débora.pdf: 3098662 bytes, checksum: 2c28fd9275298b66bf5b3a7405f356d9 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-03-26T18:30:54Z (GMT) No. of bitstreams: 1 TESE FINAL Débora.pdf: 3098662 bytes, checksum: 2c28fd9275298b66bf5b3a7405f356d9 (MD5) / Made available in DSpace on 2015-03-26T18:31:09Z (GMT). No. of bitstreams: 1 TESE FINAL Débora.pdf: 3098662 bytes, checksum: 2c28fd9275298b66bf5b3a7405f356d9 (MD5) Previous issue date: 2013-05-29 / The aim o f this study is to measure and analyze the productivity o f Brazilian mining industry as a whole and its subsectors. We first estimate multifactor productivity using the classic method proposed by Robert Solow where there was a drop in productivity in the period between 1997 and 2009. After a new estimation of productivity was made that corrects changes in the quality of the minerais extracted. It was observed that the drop in productivity in the period analyzed was even more pronounced. / O objetivo desse trabalho é medir e analisar a produtividade da indústria extrativa brasileira como um todo e seus subsetores. Primeiramente foi feita a estimação da produtividade multifatorial utilizando o método clássico proposto por Robert Solow de onde se verificou uma queda na produtividade do setor no período entre 1997 e 2009. Posteriormente foi feita uma nova estimação dessa produtividade que corrige as mudanças na qualidade dos minerais extraídos. Observou-se que a queda na produtividade, no período analisado, foi ainda mais acentuada.

Submitted by Stefano Toto (stefanototo92@gmail.com) on 2015-03-24T18:06:58Z No. of bitstreams: 1 FInal version Stefano Toto .pdf: 2666174 bytes, checksum: a92ae5ee1fd88876c05d33145bf36d74 (MD5) / Approved for entry into archive by Luana Rodrigues (luana.rodrigues@fgv.br) on 2015-03-30T13:27:41Z (GMT) No. of bitstreams: 1 FInal version Stefano Toto .pdf: 2666174 bytes, checksum: a92ae5ee1fd88876c05d33145bf36d74 (MD5) / Made available in DSpace on 2015-03-30T13:36:05Z (GMT). No. of bitstreams: 1 FInal version Stefano Toto .pdf: 2666174 bytes, checksum: a92ae5ee1fd88876c05d33145bf36d74 (MD5) Previous issue date: 2015-02-27 / This research is to be considered as an implementation of Goetzmann and Jorion (1999). In order to provide a more realistic scenario, we have implemented a Garch (1,1) approach for the residuals of returns and a multifactor model thus to better replicate the systematic risk of a market. The new simulations reveal some new aspects of emerging markets’ expected returns: the unpredictability of the emerging markets’ returns with the global factor does not depend on the year of emergence and that the unsystematic risk explains the returns of emerging markets for a much larger period of time. The results also reveal the high impact of Exchange rate, Commodities index and of the Global factor in emerging markets’ expected return.

A determinação do valor das empresas é o fator chave nas negociações de fusões e aquisições e tem por objetivo estimar uma faixa de referência que sirva como base nas negociações de tais empresas. A avaliação também é fundamental na determinação do valor de mercado das empresas. As metodologias de Fluxo de Caixa Descontado (FCD) e de múltiplos são as principais formas de se avaliar empresas. A abordagem por múltiplos baseia-se no princípio de que ativos e empresas semelhantes deveriam ter preços e múltiplos semelhantes. Os múltiplos obtidos de empresas semelhantes são aplicados aos respectivos parâmetros da empresa avaliada, dando como resultado o “valor de referência da empresa.” Entretanto as empresas comparáveis precisam apresentar fundamentos e características semelhantes. Como a regressão permite o controle das diferenças entre as variáveis que fazem os múltiplos variar de uma empresa para outra, não seria necessário limitar a procura por empresas comparáveis apenas ao setor da empresa avaliada. Desta forma, esta dissertação tem por objetivo desenvolver um modelo de estimação relativa baseada em indicadores contábeis do valor das empresas não financeiras negociadas nas principais bolsas de valores do mundo. A parte empírica desta dissertação tem por objetivo identificar quais indicadores contábeis são direcionadores de valor, ou seja, os que estão fortemente correlacionados com o valor das empresas e avaliar as relevâncias que estes indicadores assumem em bolsas e setores diferentes. / The main methodologies to value companies are Discounted Cash Flow and Relative Valuation (multiples). In relative valuation, the value of an asset is compared to the values assessed by the market for similar or comparable assets. The obtained multiple of a comparable firm, like Firm Value/EBITDA, is applied to the same parameter of the company being valued, resulting in its relative value. Otherwise, comparable companies need to have similar fundamentals and characteristics. The question of how to control for these differences, when comparing a multiple across several firms, becomes a key one. The multiple regressions can control the differences between the variables that make multiples change company by company. With the multiple regressions it would not be necessary to limit the choice of comparable companies to the one from the same sector of the company being valued. This study aims to develop a valuation model based on accounting indicators to estimate the Firm Value of listed companies of the main stock exchanges of the world. The main goal of this dissertation is to identify what accounting indicators are value drivers (that are strongly correlated with the Firm Value) and determine the relevance that these indicators have in different countries and sectors.