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Entre o criar, o copiar e o comprar pronto: a criação de instituições de ensino e pesquisa para a consolidação da indústria aeronáutica brasileira (1945-1990); Choosing among creating, copying or buying readymade: the creation of educational and research institutions (ITA and CTA) for the Brazilian aeronautical industry consolidation (1945-1990)

Oliveira, Nilda Nazaré Pereira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 07/03/2008 PT
Relevância na Pesquisa
27.15%
A presente tese tem o objetivo de analisar o processo de consolidação da indústria aeronáutica brasileira a partir de três possibilidades de geração de tecnologia para produtos ou processos: o criar, o copiar e o comprar pronto. O "criar" significa aqui a opção de desenvolver tecnologias próprias, autóctones, geradas em instituições ou empresas do próprio país e utilizadas em projetos e programas próprios, que garantam, ou possam garantir soberania econômica, política, estratégica. Para o desenvolvimento desse tipo de tecnologia de produtos e/ou processos é fundamental formar pessoal, formar grupos que dêem sustentação aos processos. O "criar" também é influenciado por fatores relacionados aos interesses dos países mais ricos. O "copiar" envolve uma forma de produzir que o Brasil já tinha experimentado na indústria de construção aeronáutica, com o exemplo das fábricas de aviões criadas pelo governo, na primeira metade do século XX, que produziam "sob licença", mas é uma forma de produzir que o Brasil já experimentava também em outras indústrias que demandam alguma "tecnologia". Muitas vezes, "copiar" está associado às "caixas pretas", sendo que, nesse caso o país não é o dono da "caixa preta". Esse tipo de produção pode ser interessante para países que não almejam um real desenvolvimento tecnológico e que servem como base de produção por possuírem mão-de-obra barata...

Executivos, gênero e smartphones: uma exploração quanto aos paradoxos tecnológicos e às copying strategies

Gonçalves, Ana Paula Borges
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Tipo: Tese de Doutorado
PT_BR
Relevância na Pesquisa
37.15%
Argumentando-se que as Tecnologias da Informação Móveis e Sem Fio (TIMS) vêm ocupando um espaço, cada vez maior, na vida dos indivíduos, e que, em função desta proximidade, novas formas de interação aparecem, este trabalho procurou aprofundar a relação entre Smartphones e Gênero. Fundamentado em abordagens teóricas relativas à existência de paradoxos associados ao uso de artefatos tecnológicos e às copying strategies adotadas pelos usuários, este estudo procurou identificar a existência e a intensidade de paradoxos associados ao uso diário de smartphones por executivos brasileiros, de ambos os sexos. O trabalho também procurou avaliar a forma como os executivos lidam com as possíveis ambiguidades vivenciadas em seus dia-a-dia. O método de estudo de caso múltiplo, cujos executivos eram as unidades de análise, foi aplicado junto a executivos mulheres e homens, usuários constantes da tecnologia smartphone e ocupantes de cargos de médio e alto escalão em grandes empresas brasileiras. A partir de um método de coleta misto – questionários, diários de uso e entrevistas em profundidade –, o trabalho teve o objetivo de aprofundar e refinar os estudos sobre paradoxos tecnológicos, bem como iniciar análises quanto à relação do gênero e esses mesmos paradoxos. Após a consolidação e análise dos dados obtidos...

Female copying increases the variance in male mating success.

Wade, M J; Pruett-Jones, S G
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1990 EN
Relevância na Pesquisa
27.15%
Theoretical models of sexual selection assume that females choose males independently of the actions and choice of other individual females. Variance in male mating success in promiscuous species is thus interpreted as a result of phenotypic differences among males which females perceive and to which they respond. Here we show that, if some females copy the behavior of other females in choosing mates, the variance in male mating success and therefore the opportunity for sexual selection is greatly increased. Copying behavior is most likely in non-resource-based harem and lek mating systems but may occur in polygynous, territorial systems as well. It can be shown that copying behavior by females is an adaptive alternative to random choice whenever there is a cost to mate choice. We develop a statistical means of estimating the degree of female copying in natural populations where it occurs.

Are Electronic Medical Records Trustworthy? Observations on Copying, Pasting and Duplication

Hammond, Kenric W.; Helbig, Susan T.; Benson, Craig C.; Brathwaite-Sketoe, Beverly M.
Fonte: American Medical Informatics Association Publicador: American Medical Informatics Association
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
Relevância na Pesquisa
27.38%
As routine use of on-line progress notes in US Department of Veterans Affairs facilities grew rapidly in the past decade, health information managers and clinicians began to notice that authors sometimes copied text from old notes into new notes. Other sources of duplication were document templates that inserted boilerplate text or patient data into notes. Word-processing and templates aided the transition to electronic notes, but enabled author copying and sometimes led to lengthy, hard-to-read records stuffed with data already available on-line. Investigators at a VA center recognized for pioneering a fully electronic record system analyzed author copying and template-generated duplication with adapted plagiarism-detection software. Nine percent of progress notes studied contained copied or duplicated text. Most copying and duplication was benign, but some introduced misleading errors into the record and some seemed possibly unethical or potentially unsafe. High-risk author copying occurred once for every 720 notes, but one in ten electronic charts contained an instance of high-risk copying. Careless copying threatens the integrity of on-line records. Clear policies, practitioner consciousness-raising and development of effective monitoring procedures are recommended to protect the value of electronic patient records.

Copying and Evolution of Neuronal Topology

Fernando, Chrisantha; Karishma, K. K.; Szathmáry, Eörs
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 20/11/2008 EN
Relevância na Pesquisa
27.25%
We propose a mechanism for copying of neuronal networks that is of considerable interest for neuroscience for it suggests a neuronal basis for causal inference, function copying, and natural selection within the human brain. To date, no model of neuronal topology copying exists. We present three increasingly sophisticated mechanisms to demonstrate how topographic map formation coupled with Spike-Time Dependent Plasticity (STDP) can copy neuronal topology motifs. Fidelity is improved by error correction and activity-reverberation limitation. The high-fidelity topology-copying operator is used to evolve neuronal topologies. Possible roles for neuronal natural selection are discussed.

Vocal copying of individually distinctive signature whistles in bottlenose dolphins

King, Stephanie L.; Sayigh, Laela S.; Wells, Randall S.; Fellner, Wendi; Janik, Vincent M.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
Publicado em 22/04/2013 EN
Relevância na Pesquisa
27.43%
Vocal learning is relatively common in birds but less so in mammals. Sexual selection and individual or group recognition have been identified as major forces in its evolution. While important in the development of vocal displays, vocal learning also allows signal copying in social interactions. Such copying can function in addressing or labelling selected conspecifics. Most examples of addressing in non-humans come from bird song, where matching occurs in an aggressive context. However, in other animals, addressing with learned signals is very much an affiliative signal. We studied the function of vocal copying in a mammal that shows vocal learning as well as complex cognitive and social behaviour, the bottlenose dolphin (Tursiops truncatus). Copying occurred almost exclusively between close associates such as mother–calf pairs and male alliances during separation and was not followed by aggression. All copies were clearly recognizable as such because copiers consistently modified some acoustic parameters of a signal when copying it. We found no evidence for the use of copying in aggression or deception. This use of vocal copying is similar to its use in human language, where the maintenance of social bonds appears to be more important than the immediate defence of resources.

Cerebral cortical mechanisms of copying geometrical shapes: a multidimensional scaling analysis of fMRI patterns of activation

Tzagarakis, Charidimos; Jerde, Trenton A.; Lewis, Scott M.; Uğurbil, Kâmil; Georgopoulos, Apostolos P.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.25%
We used multidimensional scaling (MDS) to characterize the integrative neural mechanisms during viewing and subsequently copying nine geometrical shapes. Human subjects initially looked at a central fixation point (“rest” period), then looked at a geometrical shape (“visual” period) which they copied without visual feedback (“copying” period). BOLD signal was recorded from voxels in 28 cortical areas (14 from each hemisphere) using a 4 Tesla magnet. For each voxel, signal ratios of “Visual versus Rest” (VR), and “Copy versus Visual” (CV) were calculated and used to construct two sets of Euclidean distance dissimilarity matrices for the nine shapes, with separate matrices defined for each region of interest (ROI) across subjects. The relations of perceptual and motor aspects of the shapes to MDS dimensions and specific ROIs were assessed using stepwise multiple regressions. The optimal individually scaled (INDSCAL) solutions were 2-dimensional. For the VR condition, MDS dimensions were significantly associated with the presence of crossing in a shape (Dimension 1), and with perimeter, height, cycles, peak segment speed, and horizontal symmetry (Dimension 2). ROIs most prominently associated with these dimensions essentially comprised the medial frontal lobe bilaterally...

A Contribution to the Understanding of Illegal Copying of Software: Empirical and Analytical Evidence Against Conventional Wisdom

Osorio, Carlos A.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 97500 bytes; application/pdf
EN_US
Relevância na Pesquisa
37.33%
This paper analyzes the causes of illegal copying and its effects in the software market across 66 countries. By studying the aggregated and joint effects of different variables, the analysis shows that supply constraints in the software market, shortage of after-sale support, and characteristics legal framework are major drivers of illegal copying when controlling for income per capita. It also concludes there is enough evidence to show there is a threshold of illegal copying over which its aggregated effect on the software market is positive, and this is an efficient mechanism for market creation. Thus, allowing illegal copying in some countries and at certain periods of time may be a profit generating decision in the long-term, especially in countries with low-developed software markets and with presence of Open Source software. For other hand, the results provide evidence to understand why proprietary software companies would prefer enforcing their copyrights and intellectual property rights contingently and as result of a rational decision-making process.

Fast garbage collection without a long wait

Blackburn, Stephen M; McKinley, Kathryn S
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 176182 bytes; 356 bytes; application/pdf; application/octet-stream
EN_AU
Relevância na Pesquisa
27.25%
General purpose garbage collectors have yet to combine short pause times with fast throughput. Collectors such as reference counting attain short pause times with significant performance penalties. Pure and hybrid generational collectors can achieve high throughput and have modest average pause times, but occasionally collect the whole heap and consequently incur long pauses. This paper introduces RC-hybrid, which combines copying nursery collection and reference counting the older generation to achieve both goals. Key to our algorithm is a generalization of deferred reference counting which allows RC-hybrid to safely ignore mutations to nursery objects. RC-hybrid thus restricts copying and reference counting to the objects for which they perform well. Copying collectors’ bump pointer allocation is extremely fast, and collection time is proportional to the live objects whose survival rates are low and bounded in a fixed size nursery. Reference counting time is proportional to object mutations and the number of dead objects, both of which are typically low for older objects. We further bound time spent reference counting with collection triggers and buffering. We compare RC-hybrid with pure reference counting, a stateof-the-art copying and mark-sweep hybrid...

Detection, patterns, consequences, and remediation of electronic homework copying

Palazzo, David J. (David John)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 183 p.
ENG
Relevância na Pesquisa
27.43%
The log of all interactions the student makes with an online homework tutor (MasteringPhysics), including start time, finish time, correct answers, wrong answers, and hints requested allowed the development of an algorithm which assigns a "copying" probability to each problem completed. This algorithm was applied to three successive Newtonian Mechanics classes at MIT: Fall 2003, Fall 2004, and Fall 2005, affording unique insight into the dynamics of physics homework copying, and allowing contrasts between the performance and behavioral patterns of students who copy a lot and students who copy a little or copy none at all. Observations show that repetitive homework copying is correlated with steeply declining exam performance, and that repetitive copiers are four times more likely to fail to complete the - required two semester physics sequence on time than students who don't copy. Observations of several behavioral patterns associated with repetitive homework copying are reported - these patterns, combined with data from a self-reported cheating survey of MIT freshman, shed new light on the reasons students copy and steps educators can take to reduce homework copying.; (cont.) Through the implementation of several of these steps, we observe that between Fall 2003 and Fall 2005 detected homework copying dropped by -40%. Although efforts to reduce homework copying may not be an innovation in teaching...

The role of model female quality in the mate choice copying behaviour of sailfin mollies

Hill, Sarah E; Ryan, Michael J
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.25%
Female mate choice copying is a socially mediated mate choice behaviour, in which a male's attractiveness to females increases if he was previously chosen by another female as a mate. Although copying has been demonstrated in numerous species, little is known about the specific benefits it confers to copying females. Here we demonstrate that the mate choice behaviour of female sailfin mollies (Poecilia latipinna) is influenced by the phenotypic quality of model females with whom males are observed consorting. Test females choosing between two males of similar body length were found to significantly increase time spent with previously non-preferred males after having observed them with a relatively high-quality female. Conversely, females were found to significantly decrease time spent with previously preferred males after having observed them with a relatively low-quality female. Female mate choice copying might be maintained by selection based on the heuristic value it provides females choosing between males whose quality differences are not easily distinguishable.

Eye–hand strategies in copying complex lines

Tchalenko, John; Chris Miall, R.
Fonte: Masson Publicador: Masson
Tipo: Artigo de Revista Científica
Publicado em /03/2009 EN
Relevância na Pesquisa
27.46%
Eye movements and eye–hand interactions have been recorded for 10 beginner art students copying complex lines representing outlines of caricature heads seen in profile. Four copying conditions mimicking real-world drawing situations were tested: Direct copying where the original and copy were placed side by side, Direct Blind copying where the subject could not see the drawing hand and copy, Memory copying where the original was first memorized for drawing and subsequently hidden before drawing commenced, and Non-specific Memory copying where the original was encoded for facial recognition before being hidden and drawn from memory. We observed four very different eye–hand interaction strategies which provide evidence for the eye's dual role in the copying process: acquiring visual information in order to activate the visuomotor transformation and guiding the hand on the paper. The Direct copying strategies were best understood in terms of a Drawing Hypothesis stating that shape is the result of visuomotor mapping alone and, consequently, can be accurately drawn without vision of the drawing hand or paper. A double just-in-time mechanism is proposed whereby the eye refers alternatively to the original for shape and to the copy for spatial position just in time for the drawing action to proceed continuously.

The Value of Patch-Choice Copying in Fruit Flies

Golden, Shane; Dukas, Reuven
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 06/11/2014 EN
Relevância na Pesquisa
27.33%
Many animals copy the choices of others but the functional and mechanistic explanations for copying are still not fully resolved. We relied on novel behavioral protocols to quantify the value of patch-choice copying in fruit flies. In a titration experiment, we quantified how much nutritional value females were willing to trade for laying eggs on patches already occupied by larvae (social patches). Females were highly sensitive to nutritional quality, which was positively associated with their offspring success. Females, however, perceived social, low-nutrition patches (33% of the nutrients) as equally valuable as non-social, high-nutrition ones (100% of the nutrients). In follow-up experiments, we could not, however, either find informational benefits from copying others or detect what females' offspring may gain from developing with older larvae. Because patch-choice copying in fruit flies is a robust phenomenon in spite of potential costs due to competition, we suggest that it is beneficial in natural settings, where fruit flies encounter complex dynamics of microbial communities, which include, in addition to the preferred yeast species they feed on, numerous harmful fungi and bacteria. We suggest that microbial ecology underlies many cases of copying in nature.

An Experimental Test of the Accumulated Copying Error Model of Cultural Mutation for Acheulean Handaxe Size

Kempe, Marius; Lycett, Stephen; Mesoudi, Alex
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 08/11/2012 EN
Relevância na Pesquisa
27.25%
Archaeologists interested in explaining changes in artifact morphology over long time periods have found it useful to create models in which the only source of change is random and unintentional copying error, or ‘cultural mutation’. These models can be used as null hypotheses against which to detect non-random processes such as cultural selection or biased transmission. One proposed cultural mutation model is the accumulated copying error model, where individuals attempt to copy the size of another individual's artifact exactly but make small random errors due to physiological limits on the accuracy of their perception. Here, we first derive the model within an explicit mathematical framework, generating the predictions that multiple independently-evolving artifact chains should diverge over time such that their between-chain variance increases while the mean artifact size remains constant. We then present the first experimental test of this model in which 200 participants, split into 20 transmission chains, were asked to faithfully copy the size of the previous participant's handaxe image on an iPad. The experimental findings supported the model's prediction that between-chain variance should increase over time and did so in a manner quantitatively in line with the model. However...

Local copying of orthogonal maximally entangled states and its relationship to local discrimination

Owari, Masaki; Hayashi, Masahito
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.33%
In the quantum system, perfect copying is impossible without prior knowledge. But, perfect copying is possible, if it is known that unknown states to be copied is contained by the set of orthogonal states, which is called the copied set. However, if our operation is limited to local operations and classical communications, this problem is not trivial. Recently, F. Anselmi, A. Chefles and M.B. Plenio constructed theory of local copying when the copied set consists of maximally entangled states. They also classified the copied set when it consists of two orthogonal states (New. J. Phys. 6, 164 (2004)). In this paper, we completely classify the copied set of local copying of the maximally entangled states in the prime dimensional system. That is, we prove that, in the prime dimensional system, the set of locally copiable maximally entangled states is equivalent to the set of Simultaneously Schmidt decomposable canonical form Bell states. As a result, we conclude that local copying of maximally entangled states is much more difficult than local discrimination at least in prime dimensional systems.; Comment: The material in this paper was presented on November 15, 2004 at Cambridge workshop on Quantum Statistics - Quantum Measurements...

Two qubit copying machine for economical quantum eavesdropping

Niu, Chi-Sheng; Griffiths, Robert B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.15%
We study the mapping which occurs when a single qubit in an arbitrary state interacts with another qubit in a given, fixed state resulting in some unitary transformation on the two qubit system which, in effect, makes two copies of the first qubit. The general problem of the quality of the resulting copies is discussed using a special representation, a generalization of the usual Schmidt decomposition, of an arbitrary two-dimensional subspace of a tensor product of two 2-dimensional Hilbert spaces. We exhibit quantum circuits which can reproduce the results of any two qubit copying machine of this type. A simple stochastic generalization (using a ``classical'' random signal) of the copying machine is also considered. These copying machines provide simple embodiments of previously proposed optimal eavesdropping schemes for the BB84 and B92 quantum cryptography protocols.; Comment: Minor changes. 26 pages RevTex including 7 PS figures

Entanglement Preserving in Quantum Copying of Three-qubit Entangled State

Tong, Zhao-Yang; Kuang, Le-Man
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 10/02/2004
Relevância na Pesquisa
27.25%
We study the degree to which quantum entanglement survives when a three-qubit entangled state is copied by using local and non-local processes, respectively, and investigate iterating quantum copying for the three-qubit system. There may exist inter-three-qubit entanglement and inter-two-qubit entanglement for the three-qubit system. We show that both local and non-local copying processes degrade quantum entanglement in the three-particle system due to a residual correlation between the copied output and the copying machine. We also show that the inter-two-qubit entanglement is preserved better than the inter-three-qubit entanglement in the local cloning process. We find that non-local cloning is much more efficient than the local copying for broadcasting entanglement, and output state via non-local cloning exhibits the fidelity better than local cloning.; Comment: 6 pages, 3 figures

Quantum copying: Fundamental inequalities

Hillery, Mark; Buzek, Vladimir
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/01/1997
Relevância na Pesquisa
27.15%
How well one can copy an arbitrary qubit? To answer this question we consider two arbitrary vectors in a two-dimensional state space and an abstract copying transformation which will copy these two vectors. If the vectors are orthogonal, then perfect copies can be made. If they are not, then errors will be introduced. The size of the error depends on the inner product of the two original vectors. We derive a lower bound for the amount of noise induced by quantum copying. We examine both copying transformations which produce one copy and transformations which produce many, and show that the quality of each copy decreases as the number of copies increases.; Comment: 5 pages + 1 figure, LaTeX with revtex, epsfig submitted to Phys. Rev. A

Local copying of orthogonal entangled quantum states

Anselmi, Fabio; Chefles, Anthony; Plenio, Martin B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.33%
In classical information theory one can, in principle, produce a perfect copy of any input state. In quantum information theory, the no cloning theorem prohibits exact copying of nonorthogonal states. Moreover, if we wish to copy multiparticle entangled states and can perform only local operations and classical communication (LOCC), then further restrictions apply. We investigate the problem of copying orthogonal, entangled quantum states with an entangled blank state under the restriction to LOCC. Throughout, the subsystems have finite dimension D. We show that if all of the states to be copied are non-maximally entangled, then novel LOCC copying procedures based on entanglement catalysis are possible. We then study in detail the LOCC copying problem where both the blank state and at least one of the states to be copied are maximally entangled. For this to be possible, we find that all the states to be copied must be maximally entangled. We obtain a necessary and sufficient condition for LOCC copying under these conditions. For two orthogonal, maximally entangled states, we provide the general solution to this condition. We use it to show that for D=2,3, any pair of orthogonal, maximally entangled states can be locally copied using a maximally entangled blank state. However...

Kinetic vs. energetic discrimination in biological copying

Sartori, Pablo; Pigolotti, Simone
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.15%
We study stochastic copying schemes in which discrimination between a right and a wrong match is achieved via different kinetic barriers or different binding energies of the two matches. We demonstrate that, in single-step reactions, the two discrimination mechanisms are strictly alternative and can not be mixed to further reduce the error fraction. Close to the lowest error limit, kinetic discrimination results in a diverging copying velocity and dissipation per copied bit. On the opposite, energetic discrimination reaches its lowest error limit in an adiabatic regime where dissipation and velocity vanish. By analyzing experimentally measured kinetic rates of two DNA polymerases, T7 and Pol{\gamma}, we argue that one of them operates in the kinetic and the other in the energetic regime. Finally, we show how the two mechanisms can be combined in copying schemes implementing error correction through a proofreading pathway; Comment: 18 pages, 10 figures, main text+supplementary information. Accepted for publication in Phys. Rev. Lett