989 resultados para Artificial satellites, American


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The Artificial Neural Networks (ANNs) are being used to solve a variety of problems in pattern recognition, robotic control, VLSI CAD and other areas. In most of these applications, a speedy response from the ANNs is imperative. However, ANNs comprise a large number of artificial neurons, and a massive interconnection network among them. Hence, implementation of these ANNs involves execution of computer-intensive operations. The usage of multiprocessor systems therefore becomes necessary. In this article, we have presented the implementation of ART1 and ART2 ANNs on ring and mesh architectures. The overall system design and implementation aspects are presented. The performance of the algorithm on ring, 2-dimensional mesh and n-dimensional mesh topologies is presented. The parallel algorithm presented for implementation of ART1 is not specific to any particular architecture. The parallel algorithm for ARTE is more suitable for a ring architecture.

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In this report an artificial neural network (ANN) based automated emergency landing site selection system for unmanned aerial vehicle (UAV) and general aviation (GA) is described. The system aims increase safety of UAV operation by emulating pilot decision making in emergency landing scenarios using an ANN to select a safe landing site from available candidates. The strength of an ANN to model complex input relationships makes it a perfect system to handle the multicriteria decision making (MCDM) process of emergency landing site selection. The ANN operates by identifying the more favorable of two landing sites when provided with an input vector derived from both landing site's parameters, the aircraft's current state and wind measurements. The system consists of a feed forward ANN, a pre-processor class which produces ANN input vectors and a class in charge of creating a ranking of landing site candidates using the ANN. The system was successfully implemented in C++ using the FANN C++ library and ROS. Results obtained from ANN training and simulations using randomly generated landing sites by a site detection simulator data verify the feasibility of an ANN based automated emergency landing site selection system.

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Tajunnanesitys amerikkalaisessa heterodiegeettisessä fantasiakirjallisuudessa on muuttunut merkittävästi viimeisen kolmen vuosikymmenen aikana: kerrontaa orientoiva ja tarinamaailmaa havainnoiva tajunta on vähin erin vaihtunut kaikkitietävästä kertojasta tarinan sisäiseksi henkilöhahmoksi. Kertoja on samalla vetäytynyt yhä syvemmälle kerronnan kulissien taakse. Tämä tutkielma hahmottaa ja analysoi kyseistä muutosta siirtymänä kertojakeskeisestä kerronnasta kohti henkilökeskeistä kerrontaa. Tutkielmassa tajunnanesityksen teoreettisen kehyksen muodostavat F. K. Stanzelin kertojakeskeisen ja henkilökeskeisen kerrontatilanteen käsitteet. Kerrontatilanteita tarkennetaan fokalisaation, vapaan epäsuoran esityksen, sisäisen monologin ja psykonarraation teorioiden avulla. Tutkielma jakaantuu kahteen osaan. Ensimmäisessä osassa vertaillaan kahta prototyyppistä fantasiaromaania syväluotaavan narratologisen analyysin keinoin. Kertojakeskeistä kerrontaa edustaa Fritz Leiberin "The Swords of Lankhmar" (1968) ja henkilökeskeistä kerrontaa George R. R. Martinin "A Game of Thrones" (1996). Toisessa osassa tarkastellaan pääpiirteittäin kuuttatoista muuta aikaansa edustavaa fantasiaromaania ja hahmotetaan tajunnanesityksen muutoksen kronologista kulkua. Yhdessä osat ilmentävät, kuinka amerikkalainen heterodiegeettinen fantasiakirjallisuus on muuttunut kerrontateknisesti henkilökeskeisemmäksi. Tutkielma on ensimmäinen laatuaan, ja sen on tarkoitus luoda pohjaa uudenlaiselle modernin fantasiakirjallisuuden tutkimukselle ja kirjalliselle arvostukselle.

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The concept of the American Dream was subject to a strong re-evaluation process in the 1960s, as counterculture became a prominent force in American society. A massive generation of young people, moved by the Vietnam War, the hippie movement, and psychedelic experimentation, created substantial social turbulence in their efforts to break out of conventional patterns and to create a new kind of society. This thesis outlines and analyses the concept of the American Dream in popular imagination through three works of new journalism. My primary data consists of Tom Wolfe’s The Electric Kool-Aid Acid Test (1967), Hunter S. Thompson’s Fear and Loathing in Las Vegas: A Savage Journey to the Heart of the American Dream (1971), and Norman Mailer’s Armies of the Night: History as a Novel, the Novel as History (1968). In defining the American Dream, I discuss the history of the concept as well as its manifestations in popular culture. Because of its elusive and amorphous nature, the concept of the American Dream can only be examined in cultural texts that portray the values, sentiments, and customs of a certain era. I have divided the analytical section of my thesis into three parts. In the first part I examine how the authors discuss the American society of their time in relation to ideology, capitalism, and the media. In the second part I focus on the Vietnam War and the controversy it creates in relation to the notions of freedom and patriotism. In the third part I discuss how the authors portray the countercultural visions of a better America that challenged the traditional interpretations of the American Dream. I also discuss the dark side of the new dream: the problems and disillusions that came with the effort to change the world. This thesis is an effort to trace the relocation of the American Dream in the context of the 1960s counterculture and new journalism. It hopes to provide a valuable addition to the cultural history of the sixties and to the effort of conceptualizing the American Dream.

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This work investigates the role of narrative literature in late-20th century and contemporary Anglo-American moral philosophy. It aims to show the trend of reading narrative literature for purposes of moral philosophy from the 1970 s and early 80 s to the present day as a part of a larger movement in Anglo-American moral philosophy, and to present a view of its significance for moral philosophy overall. Chapter 1 provides some preliminaries concerning the view of narrative literature which my discussion builds on. In chapter 2 I give an outline of how narrative literature is considered in contemporary Anglo-American moral philosophy, and connect this use to the broad trend of neo-Aristotelian ethics in this context. In chapter 3 I connect the use of literature to the idea of the non-generalizability of moral perception and judgment, which is central to the neo-Aristotelian trend, as well as to a range of moral particularisms and anti-theoretical positions of late 20th century and contemporary ethics. The joint task of chapters 2 and 3 is to situate the trend of reading narrative literature for the purposes of moral philosophy in the present context of moral philosophy. In the following two chapters, 4 and 5, I move on from the particularizing power of narrative literature, which is emphasized by neo-Aristotelians and particularists alike, to a broader under-standing of the intellectual potential of narrative literature. In chapter 4 I argue that narrative literature has its own forms of generalization which are enriching for our understanding of the workings of ethical generalizations in philosophy. In chapter 5 I discuss Iris Murdoch s and Martha Nussbaum s respective ways of combining ethical generality and particularity in a philosophical framework where both systematic moral theory and narrative literature are taken seriously. In chapter 6 I analyse the controversy between contemporary anti-theoretical conceptions of ethics and Nussbaum s refutation of these. I present my suggestion for how the significance of the ethics/literature discussion for moral philosophy can be understood if one wants to overcome the limitations of both Nussbaum s theory-centred, equilibrium-seeking perspective, and the anti-theorists repudiation of theory. I call my position the inclusive approach .

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This thesis presents an interdisciplinary analysis of how models and simulations function in the production of scientific knowledge. The work is informed by three scholarly traditions: studies on models and simulations in philosophy of science, so-called micro-sociological laboratory studies within science and technology studies, and cultural-historical activity theory. Methodologically, I adopt a naturalist epistemology and combine philosophical analysis with a qualitative, empirical case study of infectious-disease modelling. This study has a dual perspective throughout the analysis: it specifies the modelling practices and examines the models as objects of research. The research questions addressed in this study are: 1) How are models constructed and what functions do they have in the production of scientific knowledge? 2) What is interdisciplinarity in model construction? 3) How do models become a general research tool and why is this process problematic? The core argument is that the mediating models as investigative instruments (cf. Morgan and Morrison 1999) take questions as a starting point, and hence their construction is intentionally guided. This argument applies the interrogative model of inquiry (e.g., Sintonen 2005; Hintikka 1981), which conceives of all knowledge acquisition as process of seeking answers to questions. The first question addresses simulation models as Artificial Nature, which is manipulated in order to answer questions that initiated the model building. This account develops further the "epistemology of simulation" (cf. Winsberg 2003) by showing the interrelatedness of researchers and their objects in the process of modelling. The second question clarifies why interdisciplinary research collaboration is demanding and difficult to maintain. The nature of the impediments to disciplinary interaction are examined by introducing the idea of object-oriented interdisciplinarity, which provides an analytical framework to study the changes in the degree of interdisciplinarity, the tools and research practices developed to support the collaboration, and the mode of collaboration in relation to the historically mutable object of research. As my interest is in the models as interdisciplinary objects, the third research problem seeks to answer my question of how we might characterise these objects, what is typical for them, and what kind of changes happen in the process of modelling. Here I examine the tension between specified, question-oriented models and more general models, and suggest that the specified models form a group of their own. I call these Tailor-made models, in opposition to the process of building a simulation platform that aims at generalisability and utility for health-policy. This tension also underlines the challenge of applying research results (or methods and tools) to discuss and solve problems in decision-making processes.

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Light interception is a major factor influencing plant development and biomass production. Several methods have been proposed to determine this variable, but its calculation remains difficult in artificial environments with heterogeneous light. We propose a method that uses 3D virtual plant modelling and directional light characterisation to estimate light interception in highly heterogeneous light environments such as growth chambers and glasshouses. Intercepted light was estimated by coupling an architectural model and a light model for different genotypes of the rosette species Arabidopsis thaliana (L.) Heynh and a sunflower crop. The model was applied to plants of contrasting architectures, cultivated in isolation or in canopy, in natural or artificial environments, and under contrasting light conditions. The model gave satisfactory results when compared with observed data and enabled calculation of light interception in situations where direct measurements or classical methods were inefficient, such as young crops, isolated plants or artificial conditions. Furthermore, the model revealed that A. thaliana increased its light interception efficiency when shaded. To conclude, the method can be used to calculate intercepted light at organ, plant and plot levels, in natural and artificial environments, and should be useful in the investigation of genotype-environment interactions for plant architecture and light interception efficiency. This paper originates from a presentation at the 5th International Workshop on Functional–Structural Plant Models, Napier, New Zealand, November 2007.

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An attempt has been made at synthesis and in resolving some of the uncertainties related to the assignments of charge-transfer satellites in the X-ray photoelectron spectra of transition-metal and rare-earth compounds. New satellites are reported in the ligand core-hole spectra as well as in the metal core-level spectra of oxides of second- and third-row transition metals including rare earths. Satellites in the ligand levels and the metal levels tend to be mutually exclusive, a behaviour that can be understood on the basis of metal-ligand overlap. Systematics in the intensities and energy separations of satellites in the first-row transition-metal compounds have been examined in order to gain an insight into the nature of these satellites. A simple model involving the sudden approximation has been employed to explain the observed systematics in intensities of satellites appearing next to metal and ligand core levels on the basis of metal-ligand overlap.

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Intensive nursery systems are designed to culture mud crab postlarvae through a critical phase in preparation for stocking into growout systems. This study investigated the influence of stocking density and provision of artificial habitat on the yield of a cage culture system. For each of three batches of postlarvae, survival, growth and claw loss were assessed after each of three nursery phases ending at crab instars C1/C2, C4/C5 and C7/C8. Survival through the first phase was highly variable among batches with a maximum survival of 80% from megalops to a mean crab instar of 1.5. Stocking density between 625 and 2300 m-2 did not influence survival or growth in this first phase. Stocking densities tested in phases 2 and 3 were 62.5, 125 and 250 m -2. At the end of phases 2 and 3, there were five instar stages present, representing a more than 20-fold size disparity within the populations. Survival became increasingly density-sensitive following the first phase, with higher densities resulting in significantly lower survival (phase 2: 63% vs. 79%; phase 3: 57% vs. 64%). The addition of artificial habitat in the form of pleated netting significantly improved survival at all densities. The mean instar attained by the end of phase 2 was significantly larger at a lower stocking density and without artificial habitat. No significant effect of density or habitat on harvest size was detected in phase 3. The highest incidence of claw loss was 36% but was reduced by lowering stocking densities and addition of habitat. For intensive commercial production, yield can be significantly increased by addition of a simple net structure but rapidly decreases the longer crablets remain in the nursery.

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This paper discusses the influences of labor regulations on unionization rates through the comparative analysis of Argentina, Chile and Mexico, expecting to contribute to the understanding of the determinants of unionization in Latin America. These regulations, though only one of the factors determining unionization levels, have a crucial role, their influence being at least threefold: they define entitlements to and exclusions from the right to unionize, affect union recruitment strategies and, by generating incentives and disincentives, contribute to shape individual membership decisions. After discussing historical aspects of unionization in the three countries, the analysis centers successively in two periods in which the countries compared showed both similarities and contrasts relevant to the analysis of unionization trends. In the first, the comparison is between Argentina (1976-83) and Chile (1973-89), both under military regimes that had much in common, but with contrasting unionization trends. In the second, the focus is in Argentina (1991-2001) and Mexico (1984-2000), where the reforms implemented to liberalize the economy and ensuing social-economic and labor market transformations were similar, but unionization trends differed. It is argued that, in each case, the divergent behavior of unionization, in spite of the similar economic and sociopolitical contexts, may at least partly be attributed to differences in key labor institutions.

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"Since the founding days of the Republic, the relationship between American unionism and mass immigration has been contentious. No issue has caused the labor movement more agony and irony. It is no surprise, therefore, that throughout its history the American labor movement has sought to influence U.S. immigration policy."

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EPR spectra of lithium potassium sulfate doped with NH3+ have been recorded at 9.05 GHz. A pair of satellites can be seen symmetrically situated on either side of the main lines. The separation of the satellite lines from the main line corresponds to the 7Li NMR frequency. The distance of the interacting 7Li nucleus from the unpaired electron in NH3+ is estimated to be 3.29 Å.

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Reproduction of a painting of a meeting of the Joint Distribution Committee (representing the American Jewish Relief Committee, the Central Rellief Committee and the People's Relief Committee) and the Executive Committee of the American Jewish Relief Committee, with chairman Felix Warburg, secretary Albert Lucas, stenographer Mrs. F. Friedman, executive director Boris Bogen, comptroller Harriet Lowenstein, associate treasurer Paul Baerwald and treasurer Arthur Lehman; Office of Mr. Felix M. Warburg, 52 William Street, New York

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The genus Bagnalliella Karny is an endemic North American genus of Phlaeothripidae with 7 species associated with the New World plant genus Yucca; 2 Old World species currently placed in the genus are probably not congeneric. The number of sensoria on antennal segments III and IV has been used to distinguish the Bagnalliella species on Yucca, but an invasive population of Bagnalliella yuccae (Hinds) is reported here from Australia, at Brisbane, Queensland, in which the number of sensoria varied between individuals and even between left and right antennae of single individuals. These observations cast considerable doubt on the validity of some of the North American species of Bagnalliella. The Australian population was damaging young leaves of Yucca elephantipes, and indicates the ease with which thrips can be distributed by the horticultural trade.