Experimental component characterization, Monte Carlo-based image generation and source reconstruction for the Neutron Imaging System of the National Ignition Facility

Barrera, Carlos Andres University of California, Berkeley 2007 해외박사(DDOD)

The Neutron Imaging System (NIS) is one of seven ignition target diagnostics under development for the National Ignition Facility. The NIS is required to record hot-spot (13-15 MeV) and downscattered (6-10 MeV) images with a resolution of 10 microns and a signal-to-noise ratio (SNR) of 10 at the 20% contour. The NIS is a valuable diagnostic since the downscattered neutrons reveal the spatial distribution of the cold fuel during an ignition attempt, providing important information in the case of a failed implosion. The present study explores the parameter space of several line-of-sight (LOS) configurations that could serve as the basis for the final design. Six commercially available organic scintillators were experimentally characterized for their light emission decay profile and neutron sensitivity. The samples showed a long lived decay component that makes direct recording of a downscattered image impossible. The two best candidates for the NIS detector material are: EJ232 (BC922) plastic fibers or capillaries filled with EJ399B. A Monte Carlo-based end-to-end model of the NIS was developed to study the imaging capabilities of several LOS configurations and verify that the recovered sources meet the design requirements. The model includes accurate neutron source distributions, aperture geometries (square pinhole, triangular wedge, mini-penumbral, annular and penumbral), their point spread functions, and a pixelated scintillator detector. The modeling results show that a useful downscattered image can be obtained by recording the primary peak and the downscattered images, and then subtracting a decayed version of the former from the latter. The difference images need to be deconvolved in order to obtain accurate source distributions. The images are processed using a frequency-space modified-regularization algorithm and low-pass filtering. The resolution and SNR of these sources are quantified by using two surrogate sources. The simulations show that all LOS configurations have a resolution of 7 microns or better. The 28 m LOS with a 7 x 7 array of 100-micron mini-penumbral apertures or 50-micron square pinholes meets the design requirements and is a very good design alternative.

윌리엄 칼로스 윌리엄스 시에 나타난 시각 예술의 특징

남진우 충남대학교 대학원 2006 국내석사

Theoretische und experimentelle Untersuchung der visuellen Detektion von Objekten in Fernsehbildern : / von Giuseppe Carlo Piffaretti.

Piffaretti, Giuseppe Carlo s.n.] 1980 국내박사

Four essays on hyperinflation, money demand, and the stock market

Quintanilla, Carlos E The University of Michigan 2000 해외박사(DDOD)

During the last twenty-five years, Bolivia, Nicaragua, and Peru have undergone dramatic changes in their economic landscape going from regimes of macroeconomic stability to periods of hyperinflation and back to macroeconomic stability. These profound changes have brought with them similar changes in the economic relations studied by empirical macroeconomists. The relation between money and inflation, in particular, seems to be characterized by a case of hysteresis. This dissertation casts doubt on estimates of money demand functions obtained using recent cointegration techniques. It is shown that realistic estimates of the semi-elasticity of money demand can be generated by processes for which there is no cointegration between the log of real money balances and inflation. A simple statistical model is proposed and estimated to explain the monetary experiences of these countries. This model is used to perform a Monte Carlo study that examines the influence of regime-switches and different orders of integration on the estimation of cointegrating vectors. The results indicate that if these possibilities are not taken into account, the researcher may obtain spurious estimates of the semi-elasticity of money demand with respect to inflation. In the last chapter of this dissertation, the assumption of a constant expected return on stocks is relaxed; the zero-coupon bond rates implied by the term structure are used to discount future dividends and to construct an ex-post present discounted value of dividends, P*. This P* is closely related to the term premium. If movements in the term premium are the cause of—or at least are correlated with—movements in the expected return on stocks, this method should help explain the apparent excess volatility of stock prices first documented by Shiller. The results are mixed. One the one hand, relaxing the assumption of a constant expected return and modeling the discounting process as it done here helps in explaining more of the variation displayed by stock prices, particularly towards the end of the sample. On the other hand, this specification is still incapable of explaining the movements of, and especially the level of, the P/D in the middle of the sample.

STOCHASTIC ANALYSIS OF THE TRANSPORT OF ADSORBING POLLUTANTS IN AQUIFERS HAVING SPATIALLY VARIABLE CHEMICAL PROPERTIES (GROUNDWATER)

ESPINOZA, CARLOS A UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN 1997 해외박사

The intellectual origins of the modern Bolivian political system, 1918--1943

Aramayo, Carlos Roy Yale University 2008 해외박사(DDOD)

This dissertation tells the story of the birth of modern politics in Bolivia. It argues that the modern Bolivian political system was founded during the 1920s and 1930s by a small group of Creole intellectuals from Cochabamba. By examining the lives, family backgrounds, and social networks of prominent writers and educators, this dissertation shows how a cadre of thinkers, motivated by personal and professional desires, invented modern Bolivian politics. The intellectuals discussed in this study, including Jose Antonio Arze, Augusto Cespedes, Jose Aguirre Gainsbourg, and Carlos Montenegro, were inspired by their personal ambitions and experiences to transform Bolivian politics. They developed alliances with important social groups, particularly the labor movement and the professionalized military, during the 1920s and 1930s. These networks created a new political consciousness in Bolivia. Using a sociological approach to the history of the intelligentsia, the project argues that the disparate, often antagonistic ideologies of Bolivian modernity originated in the experiences of the nation's leading political thinkers and their relationships with key social groups. The struggles of daily life, it demonstrates, build political consciousness; the networks assembled by collective experience create politics. After the disastrous Chaco War with Paraguay and the military socialist regimes of David Toro and German Busch, these intellectuals embodied their modern ideological positions in a variety of new parties and organizations. These included the nationalist Movimiento Nacionalista Revolucionario (MNR), the Marxian Partido de la Izquierda Revolucionaria (PIR), and the Trotskyist Partido Obrero Revolucionario (POR). This dissertation traces the origins of these parties by examining the experiences of the political intellectuals who organized them. The ideologies and policies associated with modernity in Bolivia---particularly nationalism and socialism---still have currency today. The failure of "revolutionary," "reformist," and "populist" governments from the 1930s until the 2000s to fulfill the promises made by modern political institutions is a key reason for the success of Evo Morales' indigenista populism. Understanding the origins of the political, social, and cultural ideologies of the modern political system is thus crucial to comprehending Bolivia in the twenty-first century.

Topics in the theory of quantum degenerate gases

Lobo, Carlos Antonio Souza e University of Illinois at Urbana-Champaign 2001 해외박사(DDOD)

This thesis is comprised of four separate parts: in the first we calculate the second and third virial coefficients of <super>3</super>He and <super>4</super>He at low temperatures with an empirical interatomic potential by Janzen and Aziz and using the Path Integral Monte Carlo (PIMC) technique. We show that, for the calculation of the second coefficient, the method is successful whereas for the third the particular implementation that we chose (free particle sampling) is not sufficient to produce reliable results at low temperatures. In the second part we consider the Josephson Effect between two spatially separated Bose-Einstein condensates of atoms each of which can be in two hyperfine states. We derive simple equations of motion for this system closely analogous to the Bloch equations. We also map the dynamics of the system onto those of a classical particle in a well. We find novel density and spin modes of oscillation and new stable equilibrium points of the motion. Finally we analyze the oscillation modes in the spin-1 (<italic> F</italic> = 1) case. In the third part of the thesis we propose a powerful method to study the time evolution of Bose condensed gases perturbed from an initial thermal equilibrium, based on the Wigner representation of the N-body density operator. We show how to generate an ensemble of random classical fields sampling the initial Wigner distribution in the number conserving Bogoliubov approximation. The fields are then evolved with the time dependent Gross-Pitaevskii equation. We illustrate the method with the damping of a collective excitation of a one dimensional Bose gas. The fourth part deals with inhomogeneous superconductivity in the presence of magnetic fields that couple only to the spin and not to the orbital motion. They induce a splitting of the Fermi surfaces of up and down spins. We start by considering a one dimensional system and explicitly write down the wavefunction that pairs states with unequal energies due to the splitting. Next we consider an extension to three dimensions and work out explicitly certain aspects of the crossover from one to two dimensions. We then discuss the relationship of this state with those of Fulde, Ferrell, Larkin and Ovchinnikov. Finally, we consider an extension to the case of a paired state which has a gap with a spherically symmetric spatial dependence.

Low Complexity Channel Estimation in Millimeter Wave Massive MIMO Systems

SAAVEDRA ARANCIBIA CARLOS ANDRES SSCI 2018 국내석사

In millimeter-wave massive multiple input multiple output (MIMO) antenna systems, the channel estimation step is a crucial component. Unfortunately acquiring channel knowledge is a source of training overhead. In this paper, we propose two channel estimation (CE) methods leveraging measurements at sub-6 GHz frequencies to reduce training overheads. In the rst one, we extract spatial information from a sub-6 GHz channel using a virtual channel representation transformation. In the second method, we use a ray tracing technique to get a list of candidate paths for every user equipment location. We analyze how the proposed methods perform in dierent SNR scenarios and their computational complexity. Finally, we analyze the proposed methods under user equipment mobility environment. We evaluate that the proposed channel estimation methods outperform that of existed CE methods.

메노티의 20세기 단막극 오페라《전》의 음악적 표현기법연구

김한나 전북대학교 일반대학원 2018 국내석사

Opera is a synthetic art based on music. Opera was inspired by Camerata of Firenze, Italy which was purposing of the reproduction of the tragedy of ancient Greece. In the early days of the opera, it was only for the exclusive property of the privileged class, such as the nobility and royalty. Due to the appearance of mass media such as TV and movie in the 20th century, the position of the art genre, which is a purely artistic genre, has narrowed. An opera has become a performing arts for a minority of people, not the cultural art that many enjoy. Gian Carlo Menotti’s The telephone is in contrast to traditional operas, a few characters are featured in a small number of characters, shorter performance periods, and comic books. Also more characters of The telephone is that it plays on stage with other same-length productions because of the short performance, requires not a lot of people so it performs at small cost in small theaters. Instead of audiences enjoy the long playing time of traditional opera, they can enjoy short-time opera without burdens. So they called it as one-act opera and it contributed greatly to the popularization of opera. In this study, we intend to study Menotti’s The telephone in the following ways. Firstly, we will look at the definition of opera and the history of change. And then, look at the genre of European and American opera and its representative works of artists. Also, we will look at the life and works of Menotti, the composer of The Telephone. Learn through the realistic representations of characters that appear through the musical technique of The Telephone which is the actual representation of the characters and the lyrics, each major aria, focus on the musical features. This study will also use the sound of the phone to describe the tone of the characters who use the phone to sort out the emotions between the characters.

Assessment of Marketing-led Tourism Policy on Micro, Small and Medium Size Enterprises (MSMEs) in the Nicaraguan Tourism Industry, on the Pearl Lagoon Basin, Bluefields, and the Corn Islands, 2011-2017

CARLOS SAMBOLA, GLEYSI CANSY 경희대학교 대학원 2019 국내석사

Because the promotion of the tourism industry has been a goal policy for the State of Nicaragua during the recent years, it is important to evaluate the performance of these policies. For that reason, this thesis assess the National Plan for Sustainable Tourism Development of Nicaragua – Strategic Marketing Plan, as a marketing-led tourism policy implemented on the Pearl Lagoon Basin, the city of Bluefields, Corn Island and Little Corn Island (hereafter referred to as the Corn Islands) between 2011-2015 and its impact up to 2017. Using the five evaluation criteria from the Development Assistance Committee (DAC) of the Organization for Economic Cooperation and Development (OECD), which are relevance, effectiveness, efficiency, impact and sustainability, this research used a mixed approach for data collection by conducting surveys and interviews, which were analyzed using descriptive analysis and classification and categorization method of analysis; public data and journal articles were used as secondary data. The study also identifies the role of the state in the promotion and development of the tourism industry and explores possible solutions governments can used to improve tourists safety perception as a strategy to attract tourist. As a result, this thesis provides five policy implications for decision and policy makers; in order to address the major gaps in the tourism industry, shown is this study.