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Percursos da física e da energia nucleares na capital portuguesa : ciência, poder e política, 1947-1973

Gaspar, Maria Júlia Neto, 1943-
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Tese de Doutorado
Publicado em //2014 Português
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Tese de doutoramento, História e Filosofia das Ciências, Universidade de Lisboa, Faculdade de Ciências, 2014; Os contornos da relação entre ciência e poder político no período da Guerra Fria durante o Estado Novo de António de Oliveira Salazar e do seu sucessor Marcelo Caetano são analisados nesta tese através dos percursos da Física e energia nucleares na capital portuguesa, entre 1947 e 1973. Discute-se a construção do panorama científico e tecnológico português desde as contribuições da Física Nuclear experimental investigada no Laboratório de Física da Faculdade de Ciências de Lisboa ao programa nuclear adoptado pelo poder político, no pós II Guerra Mundial, associado a instituições como a Junta de Energia Nuclear e o respectivo Laboratório de Física e Engenharia Nucleares, passando também por espaços como o Centro de Estudos de Física Nuclear anexo ao Instituto Português de Oncologia e o laboratório de radioisótopos do Laboratório Nacional de Engenharia Civil. O urânio foi o intermediário da internacionalização do programa nuclear português e foi o motor da criação da Junta de Energia Nuclear na dependência da Presidência do Conselho de Ministros e do controlo de Salazar, e chefiada por homens da sua confiança política: José Frederico Ulrich...

Development of a two-fluid, two-phase model for light water reactor subchannel analysis

Kelly, J. E
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 285 leaves; 12907951 bytes; 12907707 bytes; application/pdf; application/pdf
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by John Edward Kelly.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1980.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE; Includes bibliographical references.

Performance of light water reactor fuel rods during plant power changes

Rivera, John Edward
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 246 leaves; 9271381 bytes; 9271137 bytes; application/pdf; application/pdf
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by John Edward Rivera.; Thesis (Nucl.E.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1981.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.; Includes bibliographical references.

Advanced instrumentation concepts and their appliication to nuclear power plants

Soule, Raph T. (Ralph Thomas)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 129 leaves; 7320369 bytes; 7320126 bytes; application/pdf; application/pdf
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by Ralph T. Soule.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1991, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1991.; Includes bibliographical references (leaves 102-103).

Design of a wideband, 100 W, 140 GHz gyroklystron amplifier

Joye, Colin D., 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 110 p.; 3398814 bytes; 3411983 bytes; application/pdf; application/pdf
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The design study of a 140 GHz, 100 W continuous wave gyroklystron amplifier is presented. The device is intended for use in Dynamic Nuclear Polarization (DNP) enhanced Nuclear Magnetic Resonance (NMR) spectroscopy experiments. The gyroklystron has five cavities and operates in the TE(0,2) mode with a low power electron beam. The design was performed using MAGY, a nonlinear code for modelling gyrotron devices. The design process of the gyroklystron starting from the linear theory to the optimization of the final design in MAGY has been described in detail. Stagger tuning was employed to broadband the device. The design yields 130 W peak power, 36 dB saturated gain, and a -3 dB bandwidth of over 1 GHz (0.75%) with a 15 kV, 150 mA electron beam having a beam pitch factor of 1.5, radius of 0.64 mm and calculated perpendicular momentum spread of 4%. Preliminary designs of the Magnetron Inject Gun (MIG), the input and output couplers, and the mode converter to transform the TE(0,2) operating mode to the HE(1,1) mode for low loss transmission of the output power are also presented. The design meets the specifications for the DNP experiment.; by Colin D. Joye.; Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science...

Effects of environmental protection and public safety regulatory practices upon light water reactor economics

Golay, Michael Warren.; Saragossi, Isi Isaac.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 8883161 bytes; application/pdf
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Submitted to the Department of Nuclear Engineering On May 16, 1978 in partial fulfillment of the requirements for the Degree of Master of Science in Nuclear Engineering. While there is a consensus regarding the need for extensive regulation of the nuclear power industry, the regulatory process has been the subject of almost constant controversy during recent years. Those subject to regulation complain that regulation is inefficient, that it causes unnecessary licensing and construction delays, and costs; the opponents of nuclear power charge that regulation is inadequate. This study is an effort to evaluate the performance of the regulatory process to which nuclear power plants are subject. The study is subdivided into three parts. Part one presents an analysis of the effects of regulation upon the leadtime and costs of Nuclear Power Plants in the United States. Licensing and construction delays and power plant cost increases caused by regulatory decisions during the past decade are evaluated. Part two is a brief review of the evolving differences between nuclear power plants and its main rival for base load generation, coal-fired plants, from the viewpoint of the electric utility planners. Finally, in Part three, the fundamental problems of the current regulatory process are assessed...

Communication between layers in biological transcriptional networks

Tsankov, Alex
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 89 leaves; 2107488 bytes; 2120757 bytes; application/pdf; application/pdf
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Chromatin-immunoprecipitation experiments in combination with microarrays (known as ChIP-chip) have recently allowed biologists to map where proteins bind in the yeast genome. The combinatorial binding of different proteins at or near a gene controls the transcription (copying) of a gene and the production of the functional RNA or protein that the gene encodes. Therefore, ChIP-chip data provides powerful insight on how genes and gene products (i.e., proteins, RNA) interact and regulate one another in the underlying network of the cell. Much of the current work in modeling yeast transcriptional networks focuses on the regulatory effect of a class of proteins known as transcription factors (TF). However, other sets of factors also influence transcription, including histone modifications and states (HS), histone modifiers (HM) and remodelers, nuclear processing (NP), and nuclear transport (NT) proteins. In order to gain a holistic understanding of the non-linear process of transcription, our work examines the communication between all five forementioned classes (or layers) of regulators. We use vastly available rich-media ChIP-chip data for various proteins within the five classes to model a multi-layered transcriptional network of the yeast species Saccharomyces cerevisiae.; (cont.) Following the introduction in Chapter 1...

Networking for Safeguards Education

JANSSENS-MAENHOUT GREET; CRETE Jean Maurice; BRAUNEGGER-GUELICH Anita
Fonte: OPOCE Publicador: OPOCE
Tipo: Contributions to Conferences Formato: Printed
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For nuclear technology, which involves many disciplines of science and engineering, knowledge is one of the most important resources and needs to be managed carefully. Knowledge management consists of generating, disseminating, preserving and applying expert information from different sources in an organised way. The International Nuclear Safety Advisory Group to the IAEA Director General emphasized in Note No.4 of 2001 the importance of maintaining capabilities for nuclear research and education [1]. In the European Union, nuclear engineering education at twenty-two European universities was reinforced in 2003 with the European Nuclear Education Network (ENEN) association. The academic curriculum for this Master in Nuclear Engineering does not typically include the safeguards and non-proliferation aspects of nuclear systems (fuel cycle and reactors). A newly trained nuclear engineer, although during the work possibly exposed to relevant international agreements and regulations in the area of nuclear safeguards and non-proliferation (incl. the import/export of nuclear material and/or dual use goods…) thus generally has very little knowledge of the relevant treaties, their implementation, and their control. Under the umbrella of ESARDA...

Topaz II Nuclear Powered SAR Satellite

Feuerstein, M.; Agrawal, B.N.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
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The article of record as published may be found at http://dx.doi.org/10.2514/6.1994-4688; The AA4871 Spacecraft Design course is the capstone class for the M.S. in Astronautics at the Naval Postgraduate School. Thc design team integrated a Topaz If nuclear power system with an EOS Synthetic Aperture Radar to design a low Earth orbit, three axis stabilized satellite flying in a gravity gradient stable orientation. The SAR is a high resolution, electronically stecrable, Earth science data collector for glaciology, hydrology, vegetation, occauography and geology which penetrates clouds, foliage and shallow soil layers. The antenna modulcs provide global, regional, and local high resolution mapping. Tradeoffs were analyzed to optimize coverage, satisfy nuclear safety issues, and to satisfy defined revisit and resolution requircmcnts. The design emphasized use of qualified and readily available components and subsystems. The satellite features a cylindrical monocoquc alumiiium structure, and a sun synchronous orbit simplifying thermal control design. It has a momentum bias attitude control system with momentum wheels and thrusters. The antenna has microstrip radiating elements on a honeycomb metal and composite structure and is articulated with respect to the spacecraft via an electric gimbal motor. Existing satcllitc control and data processing and distribution facilitics and an existing launch vehicle and launch site limit cost and tcchnical risk. The AA4871 Spacecraft Design course is the capstone class for the M.S. in Astronautics at the Naval Postgraduate School. Thc design team integrated a Topaz If nuclear power system with an EOS Synthetic Aperture Radar to design a low Earth orbit...

Applications of group theory to few-body physics

Chaudhary, Irfan Ullah, 1970-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 262 leaves; 8578703 bytes; 8613279 bytes; application/pdf; application/pdf
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Over the past fifteen years, there have been persistent claims of anomalous nuclear reactions in condensed matter environments. A Unified Model [38] has been proposed to systematically account for most of these anomalies. However, all the work done so far has used simple scalar nuclear Hamiltonians. In this thesis, we develop the tools necessary to use a realistic nuclear Hamiltonian in the Unified Model. A natural way to include a realistic nuclear potential in the Unified Model is via the method of coupled-channel equations. The phenomenological nuclear interaction chosen is the Hamada-Johnston potential [40]. The major portion of the thesis is devoted to deriving the coupled-channel equations with explicit symmetry constraints for the Hamada-Johnston potential. A critical input in this derivation is the calculation of the matrix elements of the various channels. We develop a systematic method, based on group theory, for calculating matrix elements of few-body correlated spatial wavefunctions. This method can, in some sense, be considered a generalization of Racah's viewpoint [17] of calculating shell-model matrix elements. Towards the end, two related, but somewhat different topics are explored. Firstly, a simple phonon-coupled nuclear reaction...

Surface Fraction Statistics of Gold Nanoclusters of Dissimilar Sizes Determined by RBS

Venkatachalam, Dinesh; Fletcher, Neville; Sood, Dinesh Kumar; Elliman, Robert
Fonte: Australian Institute of Nuclear Science and Engineering (AINSE) Publicador: Australian Institute of Nuclear Science and Engineering (AINSE)
Tipo: Conference paper
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The Fabrication of Optically Active Silica Nanowires by Ion-Implantation

Kim, Tae-Hyun; Shalav, Avi; Elliman, Robert
Fonte: Australian Institute of Nuclear Science and Engineering (AINSE) Publicador: Australian Institute of Nuclear Science and Engineering (AINSE)
Tipo: Conference paper
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Ion beam synthesis of metallic nanoparticles in SiO_2 thin films

Malik, Anwaar; Belay, K; Llewellyn, David; Hutchison, Wayne; Elliman, Robert
Fonte: Australian Institute of Nuclear Science and Engineering (AINSE) Publicador: Australian Institute of Nuclear Science and Engineering (AINSE)
Tipo: Conference paper
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The effect of ion-implantation on the resistive switching response of NiO thin films

Saleh, M.N.; Venkatachalam, Dinesh; Kim, Sung-I; Belay, Kidane; Elliman, Robert
Fonte: Australian Institute of Nuclear Science and Engineering (AINSE) Publicador: Australian Institute of Nuclear Science and Engineering (AINSE)
Tipo: Conference paper
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A new methodology in prosthesis research: radioisotope tracing of knee implant wear

Gladkis, Laura; Scarvell, Jennie; Smith, Paul; Timmers, Heiko
Fonte: Australian Institute of Nuclear Science and Engineering (AINSE) Publicador: Australian Institute of Nuclear Science and Engineering (AINSE)
Tipo: Conference paper
Português
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454.34227%

The Growth of Self-assembled Au Nanostructures during the Epitaxial Crystallization of Au-Implanted Amorphous Silicon Layers

Venkatachalam, Dinesh; Fletcher, Neville; Sood, Dinesh; Elliman, Robert
Fonte: Australian Institute of Nuclear Science and Engineering (AINSE) Publicador: Australian Institute of Nuclear Science and Engineering (AINSE)
Tipo: Conference paper
Português
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454.34227%

Evolutionary Algorithms: Concepts, Designs, and Applications in Bioinformatics: Evolutionary Algorithms for Bioinformatics

Wong, Ka-Chun
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/08/2015 Português
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Since genetic algorithm was proposed by John Holland (Holland J. H., 1975) in the early 1970s, the study of evolutionary algorithm has emerged as a popular research field (Civicioglu & Besdok, 2013). Researchers from various scientific and engineering disciplines have been digging into this field, exploring the unique power of evolutionary algorithms (Hadka & Reed, 2013). Many applications have been successfully proposed in the past twenty years. For example, mechanical design (Lampinen & Zelinka, 1999), electromagnetic optimization (Rahmat-Samii & Michielssen, 1999), environmental protection (Bertini, Felice, Moretti, & Pizzuti, 2010), finance (Larkin & Ryan, 2010), musical orchestration (Esling, Carpentier, & Agon, 2010), pipe routing (Furuholmen, Glette, Hovin, & Torresen, 2010), and nuclear reactor core design (Sacco, Henderson, Rios-Coelho, Ali, & Pereira, 2009). In particular, its function optimization capability was highlighted (Goldberg & Richardson, 1987) because of its high adaptability to different function landscapes, to which we cannot apply traditional optimization techniques (Wong, Leung, & Wong, 2009). Here we review the applications of evolutionary algorithms in bioinformatics.

Iterative Determination of Distributions by the Monte Carlo Method in Problems with an External Source

Makai, Mihály; Szatmáry, Zoltán
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/11/2013 Português
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In the Monte Carlo (MC) method statistical noise is usually present. Statistical noise may become dominant in the calculation of a distribution, usually by iteration, but is less Important in calculating integrals. The subject of the present work is the role of statistical noise in iterations involving stochastic simulation (MC method). Convergence is checked by comparing two consecutive solutions in the iteration. The statistical noise may randomize or pervert the convergence. We study the probability of the convergence, and the correct estimation of the variance in a simplified model problem. We study the statistical properties of the solution to a deterministic problem with a stochastic source obtained from a stochastic calculation. There are iteration strategies resulting in non-convergence, or randomly stopped iteration.; Comment: Accepted for publication in Nuclear Science and Engineering

Lagrange Discrete Ordinates: a new angular discretization for the three dimensional linear Boltzmann equation

Ahrens, Cory D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/05/2014 Português
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The classical $S_n$ equations of Carlson and Lee have been a mainstay in multi-dimensional radiation transport calculations. In this paper, an alternative to the $S_n$ equations, the "Lagrange Discrete Ordinate" (LDO) equations are derived. These equations are based on an interpolatory framework for functions on the unit sphere in three dimensions. While the LDO equations retain the formal structure of the classical $S_n$ equations, they have a number of important differences. The LDO equations naturally allow the angular flux to be evaluated in directions other than those found in the quadrature set. To calculate the scattering source in the LDO equations, no spherical harmonic moments are needed--only values of the angular flux. Moreover, the LDO scattering source preserves the eigenstructure of the continuous scattering operator. The formal similarity of the LDO equations with the $S_n$ equations should allow easy modification of mature 3D $S_n$ codes such as PARTISN or PENTRAN to solve the LDO equations. Numerical results are shown that demonstrate the spectral convergence (in angle) of the LDO equations for smooth solutions and the ability to mitigate ray effects by increasing the angular resolution of the LDO equations.; Comment: Submitted to Nuclear Science and Engineering

Delaware Emergency Evacuation for the Salem / Hope Creek Nuclear Power Generators

Mitchell III, Charles W.
Fonte: Universidade de Delaware Publicador: Universidade de Delaware
Tipo: Trabalho em Andamento
Português
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This report and research is an assessment of the Delaware Emergency Evacuation Plans for a radiological emergency at the Salem/Hope Creek Nuclear Power Generators in Salem, NJ. In making this assessment information is drawn from engineering as well as social science literature and the primary past nuclear emergency in the United States, Three Mile Island. The engineering research takes a look at revisions to ideas about road capacities, affects of weather on an evacuation and new methods for viewing evacuation as a process rather than list of steps, including measures of effectiveness. The Social Science literature further develops the engineering principles and is included to better understand how evacuees will respond in an emergency. This includes how the warning message will be created, understood and understanding how evacuees will choose to take protective action. This knowledge is then used to assess the current plans for the State of Delaware and make recommendations for future improvements. The information is also applied to evacuation of Delaware City, Delaware in a rough estimate of the effects of evacuation. The end result of this research is recommendations to improve methods and practices for future evacuations.