Numerical and experimental investigations for insulation particle transport phenomena in water flow

The investigation of insulation debris generation, transport and sedimentation becomes more important with regard to reactor safety research for pressurized and boiling water reactors, when considering the long-term behaviour of emergency core coolant systems during all types of loss of coolant accidents (LOCA). The insulation debris released near the break during a LOCA incident consists of a mixture of a disparate particle population that varies with size, shape, consistency and other properties. Some fractions of the released insulation debris can be transported into the reactor sump, where it may perturb or impinge on the emergency core cooling systems. Open questions of generic interest are for example the particle load on strainers and corresponding pressure-drop, the sedimentation of the insulation debris in a water pool, its possible re-suspension and transport in the sump water flow. A joint research project on such questions is being performed in cooperation with the University of Applied Science Zittau/Görlitz and the Forschungszentrum Dresden-Rossendorf. The project deals with the experimental investigation and the development of computational fluid dynamic (CFD) models for the description of particle transport phenomena in coolant flow. While the experiments are performed at the University Zittau/Görlitz, the theoretical work is concentrated at Forschungszentrum Dresden-Rossendorf. In the present paper, the basic concepts for computational fluid dynamic (CFD) modelling are described and experimental results are presented. Further experiments are designed and feasibility studies were performed.

International business research and risky investments, an analysis of FDI in conflict zones

The purpose of this paper is to examine the determinants of a firm's strategy to invest in a conflict location. To the best of our knowledge, this has not been done before. We examine this using a standard model of international business, overlaid with the fundamental approach to corporate social responsibility. We start with the population of multinationals who have chosen to invest in low income countries with weak institutions. We then split this sample in order to distinguish between firms that have invested in conflict regions compared to those that have not. Our analysis then proceeds to explain the decision of those firms to invest in conflict locations using a simple Probit model. We find that countries with weaker institutions and less concern about corporate social responsibility (CSR) are more likely to invest in conflict regions. Finally, firms with more concentrated ownership are more likely to invest in such locations. © 2012 Elsevier Ltd.

Experiments for CFD-modelling of cooling water and Insulation debris two-phase flow phenomena during loss of coolant accidents

The knowledge of insulation debris generation and transport gains in importance regarding reactor safety research for PWR and BWR. The insulation debris released near the break consists of a mixture of very different fibres and particles concerning size, shape, consistence and other properties. Some fraction of the released insulation debris will be transported into the reactor sump where it may affect emergency core cooling. Experiments are performed to blast original samples of mineral wool insulation material by steam under original thermal-hydraulic break conditions of BWR. The gained fragments are used as initial specimen for further experiments at acrylic glass test facilities. The quasi ID-sinking behaviour of the insulation fragments are investigated in a water column by optical high speed video techniques and methods of image processing. Drag properties are derived from the measured sinking velocities of the fibres and observed geometric parameters for an adequate CFD modelling. In the test rig "Ring line-II" the influence of the insulation material on the head loss is investigated for debris loaded strainers. Correlations from the filter bed theory are adapted with experimental results and are used to model the flow resistance depending on particle load, filter bed porosity and parameters of the coolant flow. This concept also enables the simulation of a particular blocked strainer with CFDcodes. During the ongoing work further results of separate effect and integral experiments and the application and validation of the CFD-models for integral test facilities and original containment sump conditions are expected.

CFD-modelling of insulation debris transport phenomena in water flow

The investigation of insulation debris generation, transport and sedimentation becomes important with regard to reactor safety research for PWR and BWR, when considering the long-term behavior of emergency core cooling systems during all types of loss of coolant accidents (LOCA). The insulation debris released near the break during a LOCA incident consists of a mixture of disparate particle population that varies with size, shape, consistency and other properties. Some fractions of the released insulation debris can be transported into the reactor sump, where it may perturb/impinge on the emergency core cooling systems. Open questions of generic interest are the sedimentation of the insulation debris in a water pool, its possible re-suspension and transport in the sump water flow and the particle load on strainers and corresponding pressure drop. A joint research project on such questions is being performed in cooperation between the University of Applied Sciences Zittau/Görlitz and the Forschungszentrum Dresden-Rossendorf. The project deals with the experimental investigation of particle transport phenomena in coolant flow and the development of CFD models for its description. While the experiments are performed at the University at Zittau/Görlitz, the theoretical modeling efforts are concentrated at Forschungszentrum Dresden-Rossendorf. Whereas the paper Alt et al. is focused on the experiments in the present paper the basic concepts for CFD modeling are described and feasibility studies including the conceptual design of the experiments are presented.

Verification and validation of numerical models of the transport of insulation debris

A combination of the two-fluid and drift flux models have been used to model the transport of fibrous debris. This debris is generated during loss of coolant accidents in the primary circuit of pressurized or boiling water nuclear reactors, as high pressure steam or water jets can damage adjacent insulation materials including mineral wool blankets. Fibre agglomerates released from the mineral wools may reach the containment sump strainers, where they can accumulate and compromise the long-term operation of the emergency core cooling system. Single-effect experiments of sedimentation in a quiescent rectangular column and sedimentation in a horizontal flow are used to verify and validate this particular application of the multiphase numerical models. The utilization of both modeling approaches allows a number of pseudocontinuous dispersed phases of spherical wetted agglomerates to be modeled simultaneously. Key effects on the transport of the fibre agglomerates are particle size, density and turbulent dispersion, as well as the relative viscosity of the fluid-fibre mixture.

Tőkebefektetések Magyarországon = Capital investments in Hungary

A tanulmány megvizsgálja Magyarország integrációs kapcsolatainak alakulását a tőkebefektetések területén, feltárja annak pozitív és negatív hatásait. Az 1990-től 2010-ig tartó periódust három fő szakaszban elemzi, ezek a szakaszok: a rendszerváltás ideje, az EU csatlakozásig, valamint a csatlakozás óta eltelt évek. Kitér a tanulmány arra, hogy a hét évvel ezelőtti uniós csatlakozás hogyan hatott a tőkebefektetések alakulására, az integráció előtti kapcsolatok milyen mértékben maradtak fent, illetve változtak, mennyire vagyunk nyitottak a külföldi tőke előtt és a 2008-ban kezdődő gazdasági világválság milyen hatással volt ezekre a folyamatokra. / === / The purpose of the study is to examine the standing of Hungary's relations within the integration especially focusing on foreign direct investment, as well as to explore its positive and negative consequences. The period between 1990 and 2010 will be discussed in three main parts, namely as the time of the political transformation, the time preceding Hungary's accession to the European Union, and that of the years passed since then. Apart from the above mentioned it is also necessary to analyze the impact made by the integration which took place seven years ago on the state of foreign direct investment, and, to have a look at the relations formed prior to it, to see the extent to which they have altered or remained the same. We need to know how much our economy is open to foreign capital and we have to understand the measure Hungary has been affected by, since the crisis that began in 2008 has made itself plausible.

Project finance in Hungarian electricity sector. Effect of feed-in tariff system’s change onto power plant investments

The research analyses the former and the current status of the small gas-motor power plant investments in the Hungarian energy sector. It discusses the development of project financing in the segment and the major changes and effects of new regulations and subsidy-policy implemented in 2010. The objective of this paper is to present the results of an empirical research of the so called GCHP projects, and to draw conclusion concerning how classic project financing conditions were present and changed during the last decade, and how regulation affected the current and future financial status of these projects.

The direct investments in Latin America and the Caribbean in the 1990s of multinational enterprises headquartered in Spain

This thesis explains why multinational enterprises (MNEs) headquartered in Spain made significant investments in Latin America in the 1990s. Two independent variables are considered: structural reforms in Latin America, and liberalization in Spain. The first independent variable concerns the ways in which Latin American governments adopted a series of reforms that made their economies attractive to foreign investors. The second variable explains how the prospects of liberalization and foreign competition led Spanish firms to invest abroad in order to expand their businesses. The study will also show the competitive advantage of Spanish MNEs, vis-a-vis other foreign and local competitors in Latin America. This thesis takes an international political economy approach. The core of the thesis shows the development of Spanish direct investment in Latin America and the Caribbean in the 1990s. The theoretical perspectives on MNEs are provided by theory of the firm, industrial organizations theory and alliance theory. ^

Temporal analysis of land use and transportation investments with geographic information system

Land use and transportation interaction has been a research topic for several decades. There have been efforts to identify impacts of transportation on land use from several different perspectives. One focus has been the role of transportation improvements in encouraging new land developments or relocation of activities due to improved accessibility. The impacts studied have included property values and increased development. Another focus has been on the changes in travel behavior due to better mobility and accessibility. Most studies to date have been conducted in metropolitan level, thus unable to account for interactions spatially and temporally at smaller geographic scales. ^ In this study, a framework for studying the temporal interactions between transportation and land use was proposed and applied to three selected corridor areas in Miami-Dade County, Florida. The framework consists of two parts: one is developing of temporal data and the other is applying time series analysis to this temporal data to identify their dynamic interactions. Temporal GIS databases were constructed and used to compile building permit data and transportation improvement projects. Two types of time series analysis approaches were utilized: univariate models and multivariate models. Time series analysis is designed to describe the dynamic consequences of time series by developing models and forecasting the future of the system based on historical trends. Model estimation results from the selected corridors were then compared. ^ It was found that the time series models predicted residential development better than commercial development. It was also found that results from three study corridors varied in terms of the magnitude of impacts, length of lags, significance of the variables, and the model structure. Long-run effect or cumulated impact of transportation improvement on land developments was also measured with time series techniques. The study offered evidence that congestion negatively impacted development and transportation investments encouraged land development. ^

Trojan horses: On the origins of national security concerns over foreign investments in the United States from 1919 to 2008

In this thesis I sought to explain the origins of national security concerns over foreign investments in the United States from 1919 to 2008. I identified and examined 29 cases of national security concerns over foreign investments in the United States during that period, and argued that in order to understand the circumstances under which foreign investments in the United States are perceived to be threats to the U.S. security we must rely on a combination of democratic peace theory and the version of political realism known as power transition theory. Thus, I tested the argument that national security concerns over foreign investments in the United States from 1919 to 2008 resulted from: (1) perceptions of international power transition, (2) perceptions of ideological and institutional differences between the United States and the home country of the investor, (3) perceptions of the strategic importance of the sector where the investment is made, and (4) perceptions of participation or control of the foreign investor by the government of the country of origin. I found that all these hypotheses have some explanatory power.

Cash Investments are Required for Restaurant Purchases

An individual considering a restaurant purchase must look at a number of major items that require financing. An initial cash investment is also necessary. The author enumerates and discusses what the buyer must have to start in business.

Relationship between Changes in Cash Flow and Investments in Publicy Traded Restaurant Firms in the United States

This research investigated the relationship between investments in fixed assets and free cash flows of U.S. restaurant firms while controlling for future investment opportunities and financial constraints. It also investigated investment and cash-flow sensitivity in the context of economic conditions. Results suggested that investments in small firms (with higher financial constraints) had relatively weaker sensitivity to cash flows than investments in large firms (with higher sensitivity). Controlling for economic conditions did not significantly change results. While the debate over sensitivity of investments to cash flows remains unresolved, it has not been explored widely in industry contexts, especially in services such as the restaurant industry. In addition to its contribution to this literature, this paper provides implications for cash-flow management in publicly traded restaurant companies.

Entrepreneur's Dilemma: Hotel Investments in Emerging Markets

Estimating the required rate of return for hotel properties is a daunting task because a lodging property is considered a hybrid between a real estate asset, and a revenue-generating enterprise affiliated with a hotel brand. Computing the expected rate of return for a hotel becomes even more complicated when a third party foreign investor/entrepreneur is the one performing the computation for an investment hotel in an emerging country. This clinical case illustrates the challenges surrounding the estimation of a project’s cost of equity in the multinational hotel industry. The results reveal that estimating cost of equity in emerging markets for hotel investments continues to be a conundrum. Future investors should make multiple adjustments and use several models when making their capital investment decisions.

The recent development and performance of ethical investments

In this chapter, we assess the recent development and performance of ethical investments around the world. Ethical investments include both socially responsible investments (following Environmental, Social and Governance criteria) and faith-based investments (following religious principles). After presenting the development of each type of funds in a historical context, we analyse their ethical screening process, highlighting similarities and differences across funds and regions. This leads us to investigate their characteristics in terms of return and risk, and finally evaluate their historical performance using various risk-adjusted performance measures on a small sample of US funds. Hence we are able to not only compare the performance of each fund with each other and with traditional investments, but also assess their relative resilience to the 2007-08 financial crisis.