Trace Oblivious Program Execution

The big data era has dramatically transformed our lives; however, security incidents such as data breaches can put sensitive data (e.g. photos, identities, genomes) at risk. To protect users' data privacy, there is a growing interest in building secure cloud computing systems, which keep sensitive data inputs hidden, even from computation providers. Conceptually, secure cloud computing systems leverage cryptographic techniques (e.g., secure multiparty computation) and trusted hardware (e.g. secure processors) to instantiate a “secure” abstract machine consisting of a CPU and encrypted memory, so that an adversary cannot learn information through either the computation within the CPU or the data in the memory. Unfortunately, evidence has shown that side channels (e.g. memory accesses, timing, and termination) in such a “secure” abstract machine may potentially leak highly sensitive information, including cryptographic keys that form the root of trust for the secure systems. This thesis broadly expands the investigation of a research direction called trace oblivious computation, where programming language techniques are employed to prevent side channel information leakage. We demonstrate the feasibility of trace oblivious computation, by formalizing and building several systems, including GhostRider, which is a hardware-software co-design to provide a hardware-based trace oblivious computing solution, SCVM, which is an automatic RAM-model secure computation system, and ObliVM, which is a programming framework to facilitate programmers to develop applications. All of these systems enjoy formal security guarantees while demonstrating a better performance than prior systems, by one to several orders of magnitude.

Conceptual guidelines for the international expansion of SMEs from Curaçao

Internationalization and moving to new markets can create many opportunities for small businesses across the globe, but also presents a number of new challenges they will face, which may influence their competitive advantage in the global market -- Present paper aims to provide an internationalization guide for SMEs from Curaçao -- Also the determinants that can impact internationalization will be discussed -- In this paper, three widely researched internationalization models form the basis of the theoretical perspectives of this paper; the traditional Uppsala model, the Network model and the Linkage, Leverage and Learning model

Interorganizational Innovation: The Role of Suppliers in Enhancing Buyer Innovation

This dissertation explores the effect of innovative knowledge transfer across supply chain partners. My research seeks to understand the manner by which a firm is able to benefit from the innovative capabilities of its supply chain partners and utilize the external knowledge they hold to increase its own levels of innovation. Specifically, I make use of patent data as a proxy for firm-level innovation and develop both independent and dependent variables from the data contained within the patent filings. I further examine the means by which key dyadic and portfolio supply chain relationship characteristics moderate the relationship between supplier innovation and buyer innovation. I investigate factors such as the degree of transactional reciprocity between the buyer and supplier, the similarity of the firms’ knowledge bases, and specific chain characteristics (e.g., geographic propinquity) to provide greater understanding of the means by which the transfer of innovative knowledge across firms in a supply chain can be enhanced or inhibited. This dissertation spans three essays to provide insights into the role that supply chain relationships play in affecting a focal firm’s level of innovation. While innovation has been at the core of a wide body of research, very little empirical work exists that considers the role of vertical buyer-supplier relationships on a firm’s ability to develop new and novel innovations. I begin by considering the fundamental unit of analysis within a supply chain, the buyer-supplier dyad. After developing initial insights based on the interactions between singular buyers and suppliers, essay two extends the analysis to consider the full spectrum of a buyer’s supply base by aggregating the individual buyer-supplier dyad level data into firm-supply network level data. Through this broader level of analysis, I am able to examine how the relational characteristics between a buyer firm and its supply base affect its ability to leverage the full portfolio of its suppliers’ innovative knowledge. Finally, in essay three I further extend the analysis to explore the means by which a buyer firm can use its suppliers to enhance its ability to access distant knowledge held by other organizations that the buyer is only connected to indirectly through its suppliers.

Volatility Spillover and Multivariate Volatility Impulse Response Analysis of GFC News Events

This paper applies two measures to assess spillovers across markets: the Diebold Yilmaz (2012) Spillover Index and the Hafner and Herwartz (2006) analysis of multivariate GARCH models using volatility impulse response analysis. We use two sets of data, daily realized volatility estimates taken from the Oxford Man RV library, running from the beginning of 2000 to October 2016, for the S&P500 and the FTSE, plus ten years of daily returns series for the New York Stock Exchange Index and the FTSE 100 index, from 3 January 2005 to 31 January 2015. Both data sets capture both the Global Financial Crisis (GFC) and the subsequent European Sovereign Debt Crisis (ESDC). The spillover index captures the transmission of volatility to and from markets, plus net spillovers. The key difference between the measures is that the spillover index captures an average of spillovers over a period, whilst volatility impulse responses (VIRF) have to be calibrated to conditional volatility estimated at a particular point in time. The VIRF provide information about the impact of independent shocks on volatility. In the latter analysis, we explore the impact of three different shocks, the onset of the GFC, which we date as 9 August 2007 (GFC1). It took a year for the financial crisis to come to a head, but it did so on 15 September 2008, (GFC2). The third shock is 9 May 2010. Our modelling includes leverage and asymmetric effects undertaken in the context of a multivariate GARCH model, which are then analysed using both BEKK and diagonal BEKK (DBEKK) models. A key result is that the impact of negative shocks is larger, in terms of the effects on variances and covariances, but shorter in duration, in this case a difference between three and six months.

Tangibilidade, classe de ativos e estrutura de capital das empresas listadas na BM&FBOVESPA

This study aims to investigate the influence of the asset class and the breakdown of tangibility as determinant factors of the capital structure of companies listed on the BM & FBOVESPA in the period of 2008-2012. Two current assets classes were composed and once they were grouped by liquidity, they were also analyzed by the financial institutions for credit granting: current resources (Cash, Bank and Financial Applications) and operations with duplicates (Stocks and Receivables). The breakdown of the tangible assets was made based on its main components provided as warrantees for loans like Machinery & Equipment and Land & Buildings. For an analysis extension, three metrics for leverage (accounting, financial and market) were applied and the sample was divided into economic sectors, adopted by BM&FBOVESPA. The data model in dynamic panel estimated by a systemic GMM of two levels was used in this study due its strength to problems of endogenous relationship as well as the omitted variables bias. The found results suggest that current resources are determinants of the capital structure possibly because they re characterized as proxies for financial solvency, being its relationship with debt positive. The sectorial analysis confirmed the results for current resources. The tangibility of assets has inverse proportional relationship with the leverage. As it is disintegrated in its main components, the significant and negative influence of machinery & equipment was more marked in the Industrial Goods sector. This result shows that, on average, the most specific assets from operating activities of a company compete for a less use of third party resources. As complementary results, it was observed that the leverage has persistence, which is linked with the static trade-off theory. Specifically for financial leverage, it was observed that the persistence is relevant when it is controlled for the lagged current assets classes variables. The proxy variable for growth opportunities, measured by the Market -to -Book, has the sign of its contradictory coefficient. The company size has a positive relationship with debt, in favor of static trade-off theory. Profitability is the most consistent variable in all the performed estimations, showing strong negative and significant relationship with leverage, as the pecking order theory predicts

Research study for an entrepreneurship practical guide

This thesis is a research study, which is aimed to be published later, in the form of a practical guide for those who have an idea and plan to go one step forward on the creation of a brand and/or a business. The main questions addressed are regarding the main concerns of an entrepreneur, identifiying the main topics that an entrepreneur's practical guide must approach. This work aims to provide relevant and important insights for those who want to start a business, taking in consideration some best practices, advises from entrepreneurs that have already started their own businesses and shared their experience. It means to provide a strong contribution to the Portuguese ecosystem, more specifically, startups, small companies, projects or ideas at seed or startup stage, brands, clubs, and every initiative which is starting from nothing, or almost nothing. Apart from books and online researches, primary information and testimonials were collected through an online survey, from a target audience of entrepreneurs, leading to the main findings of this study. The conclusion of this thesis is the gross index of the future startuper's practical guide, which will be divided in 4 different stages: Preparation, Implementation, Leverage and Closure.

A Novel Framework for Virtual Organization Creation on Cloud

Part 12: Collaboration Platforms

Engineering a Quantum Many-body Hamiltonian with Trapped Ions

While fault-tolerant quantum computation might still be years away, analog quantum simulators offer a way to leverage current quantum technologies to study classically intractable quantum systems. Cutting edge quantum simulators such as those utilizing ultracold atoms are beginning to study physics which surpass what is classically tractable. As the system sizes of these quantum simulators increase, there are also concurrent gains in the complexity and types of Hamiltonians which can be simulated. In this work, I describe advances toward the realization of an adaptable, tunable quantum simulator capable of surpassing classical computation. We simulate long-ranged Ising and XY spin models which can have global arbitrary transverse and longitudinal fields in addition to individual transverse fields using a linear chain of up to 24 Yb+ 171 ions confined in a linear rf Paul trap. Each qubit is encoded in the ground state hyperfine levels of an ion. Spin-spin interactions are engineered by the application of spin-dependent forces from laser fields, coupling spin to motion. Each spin can be read independently using state-dependent fluorescence. The results here add yet more tools to an ever growing quantum simulation toolbox. One of many challenges has been the coherent manipulation of individual qubits. By using a surprisingly large fourth-order Stark shifts in a clock-state qubit, we demonstrate an ability to individually manipulate spins and apply independent Hamiltonian terms, greatly increasing the range of quantum simulations which can be implemented. As quantum systems grow beyond the capability of classical numerics, a constant question is how to verify a quantum simulation. Here, I present measurements which may provide useful metrics for large system sizes and demonstrate them in a system of up to 24 ions during a classically intractable simulation. The observed values are consistent with extremely large entangled states, as much as ~95% of the system entangled. Finally, we use many of these techniques in order to generate a spin Hamiltonian which fails to thermalize during experimental time scales due to a meta-stable state which is often called prethermal. The observed prethermal state is a new form of prethermalization which arises due to long-range interactions and open boundary conditions, even in the thermodynamic limit. This prethermalization is observed in a system of up to 22 spins. We expect that system sizes can be extended up to 30 spins with only minor upgrades to the current apparatus. These results emphasize that as the technology improves, the techniques and tools developed here can potentially be used to perform simulations which will surpass the capability of even the most sophisticated classical techniques, enabling the study of a whole new regime of quantum many-body physics.

Aprendizagem na ação revisitada e sua relação com a noção de competência

Este artigo tem como propósito abordar, discutir e propor, a partir de cuidadosa revisão da literatura e resultados de estudo exploratório, uma concepção que procura estabelecer conexões entre as diferentes definições sobre a aprendizagem experiencial e seu papel no desenvolvimento de competências no contexto organizacional. O estudo desenvolvido investigou os aspectos relacionados à aprendizagem e ao desenvolvimento de competências na percepção de universitários que estavam trabalhando e cursando a etapa final do curso de administração. Os resultados revelam: a importância do contexto em que os indivíduos estão inseridos na construção de significados para o processo de aprendizagem; como as situações que surgem no cotidiano podem tornarse veículo neste processo; e permitem dizer que, para instalar uma cultura de aprendizagem que possibilite o desenvolvimento de competências, é necessária compreensão clara das novas diretrizes de uma tarefa educativa voltada para aprendizagem. Na perspectiva de trazer alguma contribuição o estudo conclui propondo um quadro de referências relativamente integrado para a definição e o papel da aprendizagem na ação no desenvolvimento de competências.

System Thinking to Understand Networked Innovation

Part 9: Innovation Networks

An Innovation Model for Collaborative Networks of SOA-Based Software Providers

Part 5: Service Orientation in Collaborative Networks

‘DEVOTED TO THE INTERESTS OF HIS RACE’: BLACK OFFICEHOLDERS AND THE POLITICAL CULTURE OF FREEDOM IN WILMINGTON, NORTH CAROLINA, 1865-1877

This dissertation examines black officeholding in Wilmington, North Carolina, from emancipation in 1865 through 1876, when Democrats gained control of the state government and brought Reconstruction to an end. It considers the struggle for black office holding in the city, the black men who held office, the dynamic political culture of which they were a part, and their significance in the day-to-day lives of their constituents. Once they were enfranchised, black Wilmingtonians, who constituted a majority of the city’s population, used their voting leverage to negotiate the election of black men to public office. They did so by using Republican factionalism or what the dissertation argues was an alternative partisanship. Ultimately, it was not factional divisions, but voter suppression, gerrymandering, and constitutional revisions that made local government appointive rather than elective, Democrats at the state level chipped away at the political gains black Wilmingtonians had made.

Europeanization beyond the EU: The case of Georgia.

320 p.

Adding Value to Manufacturing: Thirty Years of European Framework Program Activity

Part 1: Introduction

Capital structure and dividends : evidence from Portugal (2003-2014)

Mestrado em Finanças