819 research outputs found
Financing Dutch direct investments to transition economics
Firms interested in a direct investment in a transition countries often face difficulties in obtaining external finance. In this study Dutch survey data are used to check if financial obstacles are an important argument for Dutch firms not to engage in an FDI or if other nonfinancial arguments prevail in the decision not to invest. The analysis shows that financial problems are indeed large, but the major arguments for firms not to invest are not financial in nature. The uncertainty of the investment, lack of time and capacity and internal arguments are most often mentioned as obstacles for an FDI.financial economics and financial management ;
Interface Tracking and Solid-Fluid Coupling Techniques with Coastal Engineering Applications
Multi-material physics arise in an innumerable amount of engineering problems. A broadly
scoped numerical model is developed and described in this thesis to simulate the dynamic interaction
of multi-fluid and solid systems. It is particularly aimed at modelling the interaction
of two immiscible fluids with solid structures in a coastal engineering context; however it can
be extended to other similar areas of research. The Navier Stokes equations governing the
fluids are solved using a combination of finite element (FEM) and control volume finite element
(CVFE) discretisations. The sharp interface between the fluids is obtained through the
compressive transport of material properties (e.g. material concentration). This behaviour is
achieved through the CVFE method and a conveniently limited flux calculation scheme based
on the Hyper-C method by Leonard (1991). Analytical and validation test cases are provided,
consisting of steady and unsteady flows. To further enhance the method, improve accuracy, and
exploit Lagrangian benefits, a novel moving mesh method is also introduced and tested. It is
essentially an Arbitrary Lagrangian Eulerian method in which the grid velocity is defined by
semi-explicitly solving an iterative functional minimisation problem.
A multi-phase approach is used to introduce solid structure modelling. In this approach,
solution of the velocity field for the fluid phase is obtained using Model B as explained by
Gidaspow (1994, page 151). Interaction between the fluid phase and the solids is achieved
through the means of a source term included in the fluid momentum equations. The interacting
force is calculated through integration of this source term and adding a buoyancy contribution.
The resulting force is passed to an external solid-dynamics model such as the Discrete Element
Method (DEM), or the combined Finite Discrete Element Method (FEMDEM).
The versatility and novelty of this combined modelling approach stems from its ability to
capture the fluid interaction with particles of random size and shape. Each of the three main
components of this thesis: the advection scheme, the moving mesh method, and the solid interaction
are individually validated, and examples of randomly shaped and sized particles are
shown. To conclude the work, the methods are combined together in the context of coastal engineering
applications, where the complex coupled problem of waves impacting on breakwater
amour units is chosen to demonstrate the simulation possibilities. The three components developed
in this thesis significantly extend the application range of already powerful tools, such
as Fluidity, for fluids-modelling and finite discrete element solids-modelling tools by bringing
them together for the first time
Farming and education : an interview project advocating for farm-based education
This thesis is meant to inspire educators to value farm-based education in which farming and education come together in experiential, inquiry-based learning
The delaying effect of financing constraints on investment
We develop a simple model in which a firm considers a number of investment projects. Because of limited financial resources, the firm can undertake at most one project. In line with the literature on real options we stress features like irreversibility, uncertainty and the possibility to postpone the investment decision and argue that financing constraints tend to increase the value of waiting.Economics ;
The treatment of herpes simplex genital infection
The introduction reviews the virology, epidemiology, clinical features and previous treatments for genital herpes. The studies described here involve 6 randomised controlled trials for the treatment of genital herpes. The first was a double blind placebo controlled study of intravenous acyclovir in 30 patients with first attack genital herpes. Patients treated with acyclovir had a statistically significant reduction in the duration of viral shedding, symptoms and the time to healing, but the drug had no effect on the development of recurrences. The second study was designed to determine whether prolonged treatment of primary herpes could prevent recurrences. Sixty patients were treated with either 42 days of acyclovir or 5 days of acyclovir followed by 37 days of placebo. Prolonged treatment delayed the onset of recurrences but did not decrease their subsequent frequency. Two studies were conducted to assess the efficacy of suppressive oral acyclovir in patients with frequent recurrences. The first was a 12 week double blind placebo controlled trial in 56 patients which showed a statistically significant decrease in the frequency of recurrences in acyclovir recipients. The second assessed the safety and dosage of suppressive oral acyclovir in 134 patients over a year and showed that the likelihood of recurrences was related to dosage and the frequency of tablet taking. No important side effects were noted. The final 2 trials compared the efficacy of acyclovir and inosine pranobex. Eighty-eight patients with primary and 32 with recurrent herpes were treated. Patients with primary herpes treated with acyclovir healed more quickly and had a shorter duration of symptoms and viral shedding than those treated with inosine pranobex. Suppression with oral acyclovir was shown to be vastly superior to inosine pranobex. These studies have established that acyclovir is the drug of choice for the treatment of primary and the suppression of recurrent genital herpes
Polycentric Information Commons: A Theory Development and Empirical Investigation
Decentralized systems online—such as open source software (OSS) development, online communities, wikis, and social media—often experience decline in participation which threatens their long-terms sustainability. Building on a rich body of research on the sustainability of physical resource systems, this dissertation presents a novel theoretical framing that addresses the sustainability issues arising in decentralized systems online and which are amplified because of their open nature. The first essay develops the theory of polycentric information commons (PIC) which conceptualizes decentralized systems online as “information commons”. The theory defines information commons, the stakeholders that participate in them, the sustainability indicators of information commons and the collective-action threats putting pressure on their long-term sustainability. Drawing on Ostrom’s factors associated with stable common pool resource systems, PIC theory specifies four polycentric governance practices that can help information commons reduce the magnitude and impact of collective-action threats while improving the information commons’ sustainability. The second essay further develops PIC theory by applying it in an empirical context of “digital activism”. Specifically, it examines the role of polycentric governance in reducing the threats to the legitimacy of digital activism—a type of information commons with an overarching objective of instigating societal change. As such, it illustrates the applicability of PIC theory in the study of digital activism. The third essay focuses on the threat of “information pollution” and its impact on open collaboration, a type of information commons dedicated to the creation of value through open participation online. It uncovers the way polycentric governance mechanism help reduce the duration of pollution events. This essay contributes to PIC theory by expanding it to the realm of operational governance in open collaboration
Choice Anxiety in Decision Making: Why People Turn to Strangers for Information
This research-in-progress paper examines the conditions that cause individuals to rely on electronic word of mouth (eWoM) when making purchasing decisions. I theorize that, paradoxically, turning to strangers for information gives individuals a sense of control in a decision environment characterized by overwhelming amounts of alternatives and prevailing information asymmetries. Building on information systems (IS) literature examining questions of usage from both intentional (conscious) and automatic (subconscious) prisms, I introduce the notion of choice anxiety. I propose and test a model of how subconscious choice anxiety, together with adverse selection avoidance is associated with an individual’s sense of control based on eWoM information. I further speculate that the emergence of choice anxiety and its successful resolution triggers a classical conditioning that reinforces an individual’s reliance on eWoM information sources, thereby contributing to its institutionalization
Self-administering arithmetic enrichment activities for the more rapid learner
Thesis (Ed.M.)--Boston Universit
Regulatory Treatment of IP Transport and Services
Current U.S. regulatory policy is incoherent in its treatment of packet-oriented data
communications services. Services based on X.25, Frame Relay or ATM protocols are
regulated as telecommunications services, while IP packet transport is lumped together
with applications such as email and the World Wide Web -- and treated as an unregulated
information service. Uncertainty also reigns over the appropriate treatment of IP
telephony. As IP transport becomes an ever more significant fraction of all
telecommunications, public policy problems posed by this inconsistent treatment are likely
to increase
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