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## Avaliação da qualidade de vida e do grau de dependência dos idosos apoiados pelo serviço de apoio domiciliário da Penha de França da Santa Casa da Misericórdia de Lisboa

Pires, Marco António Estevens
Fonte: Repositório Científico Lusófona Publicador: Repositório Científico Lusófona
Português
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Objetivos: Este estudo que surge na conclusão do Iº Mestrado em Cuidados Continuados Integrados, da Escola de Ciências e Tecnologias da Saúde da Universidade Lusófona de Humanidades e Tecnologias de Lisboa, está diretamente relacionado com a prática dos Cuidados Continuados e tem como objetivo melhorar o conhecimento sobre a população idosa apoiada pelo Serviço de Apoio Domiciliário (SAD) da Penha de França (PDF) da Santa Casa da Misericórdia de Lisboa (SCML), através da Avaliação da sua Qualidade de Vida e dos seus Graus de Dependência, verificando ainda a existência de correlações entre os resultados dos instrumentos. Métodos: Realizou-se um estudo exploratório descritivo-correlacional, quantitativo e qualitativo, em que a seleção da amostra teve como critério de exclusão o défice cognitivo em que participantes não teriam diagnosticada doença Psiquiátrica, e como fatores de inclusão ter mais de 65 anos e beneficiar do serviços de SAD da PDF da SCML. Aos 40 idosos que assinaram o consentimento informado, representando cerca de 20% da população total, foi aplicado o Formulário de recolha de dados demográficos, os Índices de avaliação: das Atividades Básicas da Vida Diária (ABVD), de Barthel (IB); da avaliação das Atividades Instrumentais da Vida Diária (AIVD)...

## Ionization compression impact on dense gas distribution and star formation, Probability density functions around H ii regions as seen by Herschel

Tremblin, P.; Schneider, N.; Minier, V.; Didelon, P.; Hill, T.; Anderson, L. D.; Motte, F.; Zavagno, A.; André, Ph.; Arzoumanian, D.; Audit, E.; Benedettini, M.; Bontemps, S.; Csengeri, T.; Di Francesco, J.; Giannini, T.; Hennemann, M.; Luong, Q. Nguyen;
Tipo: Artigo de Revista Científica
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Ionization feedback should impact the probability distribution function (PDF) of the column density around the ionized gas. We aim to quantify this effect and discuss its potential link to the Core and Initial Mass Function (CMF/IMF). We used in a systematic way Herschel column density maps of several regions observed within the HOBYS key program: M16, the Rosette and Vela C molecular cloud, and the RCW 120 H ii region. We fitted the column density PDFs of all clouds with two lognormal distributions, since they present a double-peak or enlarged shape in the PDF. Our interpretation is that the lowest part of the column density distribution describes the turbulent molecular gas while the second peak corresponds to a compression zone induced by the expansion of the ionized gas into the turbulent molecular cloud. The condensations at the edge of the ionized gas have a steep compressed radial profile, sometimes recognizable in the flattening of the power-law tail. This could lead to an unambiguous criterion able to disentangle triggered from pre-existing star formation. In the context of the gravo-turbulent scenario for the origin of the CMF/IMF, the double peaked/enlarged shape of the PDF may impact the formation of objects at both the low-mass and the high-mass end of the CMF/IMF. In particular a broader PDF is required by the gravo-turbulent scenario to fit properly the IMF with a reasonable initial Mach number for the molecular cloud. Since other physical processes (e.g. the equation of state and the variations among the core properties) have already been suggested to broaden the PDF...

## Viscous Instanton for Burgers' Turbulence

Balkovsky, E.; Falkovich, G.; Kolokolov, I.; Lebedev, V.
Tipo: Artigo de Revista Científica
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We consider the tails of probability density functions (PDF) for different characteristics of velocity that satisfies Burgers equation driven by a large-scale force. The saddle-point approximation is employed in the path integral so that the calculation of the PDF tails boils down to finding the special field-force configuration (instanton) that realizes the extremum of probability. We calculate high moments of the velocity gradient $\partial_xu$ and find out that they correspond to the PDF with $\ln[{\cal P}(\partial_xu)]\propto-(-\partial_xu/{\rm Re})^{3/2}$ where ${\rm Re}$ is the Reynolds number. That stretched exponential form is valid for negative $\partial_xu$ with the modulus much larger than its root-mean-square (rms) value. The respective tail of PDF for negative velocity differences $w$ is steeper than Gaussian, $\ln{\cal P}(w)\sim-(w/u_{\rm rms})^3$, as well as single-point velocity PDF $\ln{\cal P}(u)\sim-(|u|/u_{\rm rms})^3$. For high velocity derivatives $u^{(k)}=\partial_x^ku$, the general formula is found: $\ln{\cal P}(|u^{(k)}|)\propto -(|u^{(k)}|/{\rm Re}^k)^{3/(k+1)}$.; Comment: 15 pages, RevTeX 3.0

## Intermittent scaling of the probability density function tail of the Kardar-Parisi-Zhang equation

Anderson, Johan; Johansson, Jonas
Tipo: Artigo de Revista Científica
Português
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This letter provides the first analytical estimation of the probability density function (PDF) tail of the interface width in the Kardar-Parisi-Zhang equation in the regime of strongly non-linear growth. We find that the PDF tail is proportional to $\exp{- c w_2^{3/2}}$. In addition, the effect of spatial dimensions on the PDF tail scaling is dicussed. The PDF tail is computed by the instanton method within the Martin-Rose-Siggia framework using a careful treatment of the non-linear term. This gives a novel approach to understand the rightmost PDF tail of the interface width distribution and the analysis suggests that there is no limit in the upper critical dimension.; Comment: 6 pages, 2 figures, submitted to EPL

## Observational Diagnostics of Self-Gravitating MHD Turbulence in Giant Molecular Clouds

Burkhart, Blakesley; Collins, David C.; Lazarian, Alex
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
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We study the observable signatures of self-gravitating MHD turbulence by applying the probability density functions (PDFs) and the spatial density power spectrum to synthetic column density maps. We find that there exists three characterizable stages of the evolution of the collapsing cloud which we term "early," "intermediate," and "advanced." At early times, i.e. $t<0.15t_{ff}$, the column density has a power spectral slope similar to nongravitating supersonic turbulence and a lognormal distribution. At an intermediate stage, i.e. $0.15t_{ff}< t \leq 0.35t_{ff}$, there exists signatures of the prestellar cores in the shallower PDF and power spectrum power law slopes. The column density PDF power law tails at these times have line of sight averaged slopes ranging from -2.5 to -1.5 with shallower values belonging to simulations with lower magnetic field strength. The density power spectrum slope becomes shallow and can be characterized by $P(k)=A_1k^{\beta_2}e^{-k/k_c}$, where $A_1$ describes the amplitude, $k^{\beta_2}$ describes the classical power law behavior and the scale $k_c$ characterizes the turn over from turbulence dominated to self-gravity dominated. At advanced stages of collapse, i.e. $\approx t>0.35t_{ff}$, the power spectral slope is positive valued...

## Incorporating Photometric Redshift Probability Density Information into Real-Space Clustering Measurements

Myers, Adam D; White, Martin; Ball, Nicholas M.
Tipo: Artigo de Revista Científica
Português
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The use of photometric redshifts in cosmology is increasing. Often, however these photo-zs are treated like spectroscopic observations, in that the peak of the photometric redshift, rather than the full probability density function (PDF), is used. This overlooks useful information inherent in the full PDF. We introduce a new real-space estimator for one of the most used cosmological statistics, the 2-point correlation function, that weights by the PDF of individual photometric objects in a manner that is optimal when Poisson statistics dominate. As our estimator does not bin based on the PDF peak it substantially enhances the clustering signal by usefully incorporating information from all photometric objects that overlap the redshift bin of interest. As a real-world application, we measure QSO clustering in the Sloan Digital Sky Survey (SDSS). We find that our simplest binned estimator improves the clustering signal by a factor equivalent to increasing the survey size by a factor of 2-3. We also introduce a new implementation that fully weights between pairs of objects in constructing the cross-correlation and find that this pair-weighted estimator improves clustering signal in a manner equivalent to increasing the survey size by a factor of 4-5. Our technique uses spectroscopic data to anchor the distance scale and it will be particularly useful where spectroscopic data (e.g...

## Evolution of Cosmological Density Distribution Function from the Local Collapse Model

Ohta, Yasuhiro; Kayo, Issha; Taruya, Atsushi
Tipo: Artigo de Revista Científica
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We present a general framework to treat the evolution of one-point probability distribution function (PDF) for cosmic density $\delta$ and velocity-divergence fields $\theta$. In particular, we derive an evolution equation for the one-point PDFs and consider the stochastic nature associated with these quantities. Under the local approximation that the evolution of cosmic fluid fields can be characterized by the Lagrangian local dynamics with finite degrees of freedom, evolution equation for PDFs becomes a closed form and consistent formal solutions are constructed. Adopting this local approximation, we explicitly evaluate the one-point PDFs $P(\delta)$ and $P(\theta)$ from the spherical and the ellipsoidal collapse models as the representative Lagrangian local dynamics. In a Gaussian initial condition, while the local density PDF from the ellipsoidal model almost coincides with the that of the spherical model, differences between spherical and ellipsoidal collapse model are found in the velocity-divergence PDF. Importantly, the joint PDF of local density, $P(\delta,t;\delta',t')$, evaluated at the same Lagrangian position but at the different times $t$ and $t'$ from the ellipsoidal collapse model exhibits a large amount of scatter. The mean relation between $\delta$ and $\delta'$ does fail to match the one-to-one mapping obtained from spherical collapse model. Moreover...

## An improved measurement of the flux distribution of the Ly-alpha forest in QSO absorption spectra: the effect of continuum fitting, metal contamination and noise properties

Kim, T. -S.; Bolton, J. S.; Viel, M.; Haehnelt, M. G.; Carswell, R. F.
Tipo: Artigo de Revista Científica
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We have performed an extensive Voigt profile analysis of the neutral hydrogen (HI) and metal absorption present in a sample of 18 high resolution, high signal-to-noise QSO spectra observed with VLT/UVES. We use this analysis to separate the metal contribution from the HI absorption and present an improved measurement of the flux probability distribution function (PDF) due to HI absorption alone at = 2.07, 2.52, and 2.94. The flux PDF is sensitive to the continuum fit in the normalised flux range 0.8 < F < 1.0 and to metal absorption at 0.2 < F < 0.8. Our new measurements of the flux PDF due to HI absorption alone are systematically lower at 0.2 < F < 0.8 by up to 30% compared to the widely used measurement of McDonald et al. (2000), based on a significantly smaller sample of Keck/HIRES data. This discrepancy is probably due to a combination of our improved removal of the metal absorption and cosmic variance, since variations in the flux PDF between different lines-of-sight are large. The HI effective optical depth at 1.7 < z < 4 is best fit with a single power law, (0.0023 +-0.0007) (1+z)^(3.65 +- 0.21), in good agreement with previous measurements from comparable data. As also found previously, the effect of noise on the flux distribution is not significant in high resolution...

## The Probability Distribution Function of Light in the Universe: Results from Hydrodynamic Simulations

Ostriker, Jeremiah P.; Nagamine, Kentaro; Cen, Renyue; Fukugita, Masataka
Tipo: Artigo de Revista Científica
Português
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While second and higher order correlations of the light distribution have received extensive study, the lowest order probability distribution function (PDF) -- the probability that a unit volume of space will emit a given amount of light -- has received very little attention. We estimate this function with the aid of hydrodynamic simulations of the Lambda CDM model, finding it significantly different from the mass density PDF, and not simply related to it by linear bias or any of the other prescriptions commonly adopted. If the optical light PDF is, in reality, similar to what we find in the simulations, then some measures of Omega_M based on mass-to-light ratio and the cosmic virial theorem will have significantly underestimated Omega_M. Basically, the problem is one of selection bias, with galaxy forming regions being unrepresentative of the dark matter distribution in a way not described by linear bias. Knowledge of the optical PDF and the plausible assumption of a log-normal distribution for the matter PDF will allow one to correct for these selection biases. We find that this correction (which amounts to 20-30%) brings the values of Omega_M estimated by using the mass-to-light ratio and the cosmic virial theorem to the range 0.2-0.3...

## Investigation of the errors in SDSS proper-motion measurements using samples of quasars

Dong, Ruobing; Gunn, James; Knapp, Gillian; Rockosi, Constance; Blanton, Michael
Tipo: Artigo de Revista Científica
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We investigate in detail the probability distribution function (pdf) of the proper-motion measurement errors in the SDSS+USNO-B proper-motion catalog of \citet{mun04} using clean quasar samples. The pdf of the errors is well-represented by a Gaussian core with extended wings, plus a very small fraction ($<0.1%$) of "outliers". We find while formally the pdf could be well-fit by a five-parameter fitting function, for many purposes it is also adequately to represent the pdf with a one-parameter approximation to this function. We apply this pdf to the calculation of the confidence intervals on the true proper motion for a SDSS+USNO-B proper motion measurement, and discuss several scientific applications of the SDSS proper motion catalogue. Our results have various applications in studies of the galactic structure and stellar kinematics. Specifically, they are crucial for searching hyper-velocity stars in the Galaxy.; Comment: 26 pages (single column), 11 figures, accepted in AJ

## Density Probability Distribution Functions in Supersonic Hydrodynamic and MHD Turbulence

Lemaster, M. Nicole; Stone, James M.
Tipo: Artigo de Revista Científica
Português
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We study the probability distribution function (PDF) of the mass density in simulations of supersonic turbulence with properties appropriate for molecular clouds. For this study we use Athena, a new higher-order Godunov code. We find there are surprisingly similar relationships between the mean of the time-averaged PDF and the turbulent Mach number for driven hydrodynamic and strong-field MHD turbulence. There is, however, a large scatter about these relations, indicating a high level of temporal and spatial variability in the PDF. Thus, the PDF of the mass density is unlikely to be a good measure of magnetic field strength. We also find the PDF of decaying MHD turbulence deviates from the mean-Mach relation found in the driven case. This implies that the instantaneous Mach number alone is not enough to determine the statistical properties of turbulence that is out of equilibrium. The scatter about the mean-Mach relation for driven turbulence, along with the large departure of decaying turbulence PDFs from those of driven turbulence, may illuminate one factor contributing to the large observed cloud-to-cloud variation in the star formation rate per solar mass.; Comment: 4 pages, 2 figures, published in ApJL; corrected sign in eqn. (4)

## The Gram-Charlier A Series based Extended Rule-of-Thumb for Bandwidth Selection in Univariate and Multivariate Kernel Density Estimations

C, Dharmani Bhaveshkumar
Tipo: Artigo de Revista Científica
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The article derives a novel Gram-Charlier A (GCA) Series based Extended Rule-of-Thumb (ExROT) for bandwidth selection in Kernel Density Estimation (KDE). There are existing various bandwidth selection rules achieving minimization of the Asymptotic Mean Integrated Square Error (AMISE) between the estimated probability density function (PDF) and the actual PDF. The rules differ in a way to estimate the integration of the squared second order derivative of an unknown PDF $(f(\cdot))$, identified as the roughness $R(f''(\cdot))$. The simplest Rule-of-Thumb (ROT) estimates $R(f''(\cdot))$ with an assumption that the density being estimated is Gaussian. Intuitively, better estimation of $R(f''(\cdot))$ and consequently better bandwidth selection rules can be derived, if the unknown PDF is approximated through an infinite series expansion based on a more generalized density assumption. As a demonstration and verification to this concept, the ExROT derived in the article uses an extended assumption that the density being estimated is near Gaussian. This helps use of the GCA expansion as an approximation to the unknown near Gaussian PDF. The ExROT for univariate KDE is extended to that for multivariate KDE. The required multivariate AMISE criteria is re-derived using elementary calculus of several variables...

## The momentum flux probability distribution function for ion-temperature-gradient turbulence

Anderson, Johan; Kim, Eun-jin
Tipo: Artigo de Revista Científica
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There has been overwhelming evidence that coherent structures play a critical role in determining the overall transport in a variety of systems. We compute the probability distribution function (PDF) tails of momentum flux and heat flux in ion-temperature-gradient turbulence, by taking into account the interaction among modons, which are assumed to be coherent structures responsible for bursty and intermittent events, contributing to the PDF tails. The tail of PDF of momentum flux $R = < v_x v_y>$ is shown to be exponential with the form $\exp{\{-\xi R^{3/2}\}}$, which is broader than a Gaussian, similarly to what was found in the previous local studies. An analogous expression with the same functional dependence is found for the PDF tails of heat flux. Furthermore, we present a detailed numerical study of the dependence of the PDF tail on the temperature and density scale lengths and other physical parameters through the coefficient $\xi$.; Comment: 23 pages, 2 figures

## Turbulent partially premixed combustion: DNS analysis and RANS simulation

Ruan, S.
Fonte: University of Cambridge; Department of Engineering Publicador: University of Cambridge; Department of Engineering
Tipo: Thesis; doctoral; PhD
Português
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Increasingly stringent regulation of pollutant emission has motivated the search for cleaner and more efficient combustion devices, which remain the primary means of power generation and propulsion for all kinds of transport. Fuel-lean premixed combustion technology has been identified to be a promising approach, despite many difficulties involve, notably issues concerning flame stability and ignitability. A partially premixed system has been introduced to remedy these problems, however, our understanding on this combustion mode needs to be greatly improved to realise its full potential. This thesis aims to further the understanding of various fundamental physical processes in turbulent partially premixed flames. DNS data of a laboratory-scale hydrogen turbulent jet lifted flame is analysed in this study. The partially premixed nature of this flame is established by examining the instantaneous and averaged reaction rates and the "Flame Index", which indicate premixed and diffusion burning modes coexisting. The behaviour of turbulent flame stretch and its relation to other physical processes, in particular the scalar-turbulence interaction, the effects of partial premixing on the displacement speed of iso-scalar surface and its correlation with the surface curvature are explored using DNS data. The scalar gradient alignment characteristics change from aligning with the most compressive strain to aligning with the most extensive one in regions of intensive heat release. This alignment change creates negative normal strain rate which can result in negative surface averaged tangential strain rate. The partial premixing affects the flame surface displacement speed through the mixture fraction dissipation rate and a second derivative in the mixture fraction space. The correlation of curvature and displacement speed is found to be negative in general and the effects of partial premixing act to reduce this negative correlation. The combined effects of the normal strain rate and the displacement speed/curvature correlation contribute to the negative mean flame stretch observed in the flame brush. Scalar dissipation rates (SDR) of the mixture fraction ?ZZ...

## A multirate DSP model for estimation of discrete probability density functions

Yoon, Byung-Jun; Vaidyanathan, P. P.
Fonte: Instituto de Tecnologia da Califórnia Publicador: Instituto de Tecnologia da Califórnia
Tipo: Article; PeerReviewed Formato: application/pdf
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The problem of estimating a probability density function (PDF) from measurements has been widely studied by many researchers. Even though much work has been done in the area of PDF estimation, most of it was focused on the continuous case. We propose a new model-based approach for modeling and estimating discrete probability density functions or probability mass functions. This approach is based on multirate signal processing theory, and it has several advantages over the conventional histogram method. We illustrate the PDF estimation procedure and analyze the statistical properties of the PDF estimates. Based on this model, a novel scheme is introduced that can be used for estimating the PDF in the presence of noise. Furthermore, the proposed ideas are extended to the more general case of estimating multivariate PDFs. Finally, we also consider practical issues such as optimizing the coefficients of a digital filter, which is an integral part of the model. This allows us to apply the proposed model to solve real-world problems. Simulation results are given where appropriate in order to demonstrate the ideas.

## An Investigation into the distuibution of portable documents in a prepress environment

Conroy, Timothy
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Português
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Portable document files (PDF's) are used in many types of environments; such as, office, world wide web, and desktop publishing to name a few. PDF technology allows electronic documents to become truly portable. PDF files maintain their original look and feel across various computer systems and platforms. PDF use in a prepress environment was tested by creating various electronic mechanicals with numerous file formats and having these PDF files imaged across the country on various high resolution imagesetting devices. It has been determined that PDF files can be used in a prepress environment at this point in time in some situations.

## O sucesso da inculturação do telemóvel nas comunidades moçambicanas e a sua múltipla funcionalidade social

Joanguete, Celestino Vaz
Fonte: Revista Observatório Publicador: Revista Observatório
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
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A estrutura do trabalho é construída em três momentos: o primeiro  discute a empregabilidade no dispositivo móvel na monitoria de governação. Nesta abordagem a reflexão tráz à superfície a questão do uso das mensagens SMS na monitoria dos processos eleitorais. O segundo momento debruça sobre o telemóvel no processo comunicativo, no qual são enfatizados os últimos progressos tecnológicos das infraestruturas de comunicação; o terceiro momento descreve o impactos da "Economia Móvel" nos processos de desenvolvimento do negócio e transações comerciais, onde se destaca o impacto social dos serviços móveis de consulta, transferências bancárias e pagamentos de serviços. Palavras-chave: Telemóvel; comunicação; economia móvel.   ABSTRACT The structure of the work is built in two stages: The first discusses employability in the governance mobile monitoring device. In this approach to reflect back to the surface the issue of the use of SMS messages in the monitoring of electoral processes. The second phase focuses on the mobile phone in the communicative process in rural areas, which are emphasized in the latest technological advances in communications the impact  infrastructure; the third phase describes the phone incorporating  on business development processes and business transactions...

## Violência doméstica: análise e correlações do perfil educacional de autores e vítimas na cidade de arraias nos anos de 2012 a 2014

Silva, João Nunes da; Sousa, Ronan Almeida; Borges, Marlene Alves
Fonte: Revista Observatório Publicador: Revista Observatório
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
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Este estudo teórico/prático versa sobre a violência doméstica, problema de âmbito mundial. No Brasil conforme muitas pesquisas, tal violência tem inúmeras motivações, sobretudo cultural. A cidade de Arraias-TO não é exceção, sendo este tipo de violência fato recorrente naqueles lares, cidade objeto do estudo. Buscou-se evidenciar de forma sintética a problemática em nível mundial, nacional e por fim, em uma esfera mais detalhada, nos lares arraianos. O objetivo deste estudo foi compreender a violência doméstica a partir da aplicação e efetividade da Lei Maria da Penha correlacionando os fatos ao perfil educacional/profissional dos agressores e vítimas nos casos registrados na cidade de Arraias e verificar o quanto tal perfil interfere nos índices de violência praticada contra mulheres, bem ainda a recorrência dos fatos frente aos índices de retratações das ofendidas. Para tanto, se utilizou de fundamentação teórica, bem como da pesquisa de campo, com análise de 100% dos casos registrados nos últimos três anos na delegacia daquela circunscrição. Foram observados os boletins de ocorrências realizados pela aquela Unidade Policial a fim de se visualizar a aplicação e efetividade da lei. A análise recaiu ainda nos seguintes documentos: autos de procedimentos criminais...

## Dissertation Abstract; Resumo de Dissertação 10.5007/1518-2924.2006v11n22pii

Encontros Bibli, Editor
Fonte: Departamento de Ciência da Informação – UFSC Publicador: Departamento de Ciência da Informação – UFSC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf; application/pdf; application/pdf; application/pdf; application/pdf