Documents found
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2471.
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2474.More information
Various forms of data are presented in the current information environment : confidential commercial or government data, big data, government open data, and linked open data of the Semantic Web. How should information professionals prepare themselves to handle or process the different types of data ? We suggest that this preparation be based on three aspects : a clear understanding of the different types of data, an initiation to the resources required to process each type of data and an understanding of the impact that each type will have on information science as a discipline and on the practice of information professionals.
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2475.More information
Keywords: RÉFLEXION, RÉFLEXIVITÉ, PRATIQUE RÉFLEXIVE, RÉFLEXION SUR LA PRATIQUE, ENSEIGNEMENT, ENSEIGNANT, PROFESSIONNEL, APPRENTISSAGE, DÉVELOPPEMENTPROFESSIONNEL, PÉDAGOGIE UNIVERSITAIRE
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2476.More information
Me-ssiah Antoine, Escaffrf Noëlle. Sannino Nadine, Rothy Michel Gai imi r-Pvjoi Anne - Sexuality in the age of AIDS in a vulnerable population: findings from a survey on prisoners This article analyses data on the previous sexual behaviour of prisoners entering the Marseille Centre Pénitentiaire between December 1995 and March 1997 (520 men and 54 women, adults) Compared with the general population, the prisoners are younger, more likely to be single, are less well-qualified, and more likely to have been unemployed before prison They became sexually active younger, and are more likely to have been rape victims and been involved in prostitution, than adults in general They are more likely to have had multiple partnerships and have a wider repertoire of sexual practices Similar conclusions emerge when prisoners who have served several prison sentences are compared with first time prisoners In addition, prisoners who have already been in prison are more likely to be injecting drug users and HIV positive, as also is their last sexual partner On the other hand, they are more likely to have been tested for HIV and to use condoms, as are prisoners in general compared with the ge neral population When these prevention behaviours are taken into account, the risk of sexual transmission of HIV is shown to be higher among those imprisoned several times than among first-time prisoners In a context of greater social and sexual vulnerability, prisoners have a risk of sexual exposure to and transmission of HIV higher than the general population The number of spells in prison is a good indicator of the degree of vulnerability and risk
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2477.More information
Installed in a partially collapsed rock shelter, the Early Bronze Age funerary complex of Les Renardières (Charente, France) consists of three areas which are still covered and more or less organised with stones, where the remains of the dead, mainly children, were deposited; these areas surround a central zone, apparently dedicated to ceremonies, which contained only ceramics. Proposing as their main hypothesis the existence of a final disposal during double funerals, the authors discuss the organisation of this complex, the various aspects of its functioning, which globally remind us of earlier complexes from the late Neolithic, and modalities of dealing with the dead.
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2478.More information
During the second half of the eighteenth century, the figure of the librarian underwent essential changes in the writings of Italian literati. Next to the scholar reading by candlelight, they emphasised a new character, hired and paid in exchange for his intellectual and technical expertise. The present survey aims to assess how and to what extent this change in discourse actually reflected the social, institutional and intellectual processes of the time. It begins by gathering contemporary opinions on librarians, what they should know and how they should be hired and paid. Such statements relate to a general context in which «library policies » were being developed by Italian states, libraries were becoming more diverse and intellectual work was gaining recognition as such. By submitting a sample of 175 individuals to a prosopographical survey, and thus constructing a typology of the careers of librarians in eighteenth-century Italy, further light is shed on the social reality of their profession.
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2479.More information
The hydraulic models that are used to simulate floods in rural areas are not adapted to model floods through urban areas, because of details that may deviate flows and create strong discontinuities in the water levels, and because of the possible water flow running in the sewage network. However, such modelling is strongly required because damage is often concentrated in urban areas. Thus, it is necessary to develop models specifically dedicated to such floods. In the southern part of France, rains may have a high intensity but floods generally last a few hours. During extreme events such as the October 1988 flood in the city of Nîmes, most of the flow remained on the ground with high water depths and high velocities, and the role of sewage network can be neglected. A 1-D model and a 2-D model were used to calculate such flows, which may become supercritical. On the catchments of the streams which cross the city of Nîmes, the rainfall was estimated as 80 mm in one hour and 250 mm in six hours in October 1988, although some uncertainties remain. The return period can be estimated between 150 and 250 years. The zone selected to test the models was an area 1.2 km long and less than 1 km wide in the north-eastern part of the city. It includes a southern part with a high density of houses. The slope from the North (upstream) to the South (downstream) was more than 1 % on average and was decreasing from North to South. Various topographical and hydrological data were obtained from the local Authorities. The basic data were composed of 258 cross sections of 69 streets with 11 to 19 points for each cross section. Observations of the limits of the flooded areas and of the peak water levels at more than 80 points can be used to validate the calculation results. The inputs consisted of two discharge hydrographs, estimated from a rainfall-discharge model from rains with a return period of 100 years, which may result in an underestimate of these inputs. These two hydrographs correspond to the two main structures that cross the railway embankment, which constitutes an impervious upstream boundary of the modelled area. Whereas the western and eastern boundaries are well delimitated by hills above maximum water levels, the downstream southern boundary is somewhat more questionable because of possibilities of backwater and inflows from neighbouring areas.The 1-D software REM2U solved the Saint Venant equations on a meshed network. At crossroads, continuities of discharge and of water heads were set. The hydraulic jump was modelled by a numerical diffusion applied wherever high water levels were found. The Lax Wendroff numerical scheme was implemented. It included a prediction step and a correction step, which implied precise solving of these very unsteady and hyperbolic problems. The software was validated on numerous test cases (Al Mikdad, 2000) which proved the adaptation to problems of calculations in a network of streets.The 2-D software Rubar 20 solves 2-D shallow water equations by an explicit second-order Van Leer type finite volume scheme on a computational grid made from triangles and quadrilaterals (Paquier, 1998). The discontinuities (hydraulic jumps for instance) are treated as ordinary points through the solving of Riemann problems. For the Nîmes case, the grid was built from the cross sections of the streets. Four grids were built with respectively 4, 5, 7 or 11 points for every cross section and these points correspond to the main characteristics of the cross section: the walls of the buildings, the sidewalks, the gutters and the middle point. The simplest crossroads were described from the crossings of the lines corresponding to these points, which provide respectively 16, 25, 49 or 121 computational cells. The space step was about 25 metres along the streets but went as low as 0.1 m in the crossroads; due to the explicit scheme, which implies that the Courant number was limited to 1, the time step was very small and a long computational time was required.The computations were performed with a uniform Strickler coefficient of 40 m1/3/s. Both 1-D and 2-D models provided results that agreed well with observed water levels. The limits of the flooded area were also quite well simulated. However, locally, the differences between calculated and observed maximum water depths were high, resulting in an average deviation of about 1 metre. The reasons for such deviations could come from three main causes. First, the uncertainty of topographical data is relatively high, because of the interpolation between measured cross sections without a detailed complementary DEM (digital elevation model). Second, the observed levels were also uncertain and reveal local situations that are not reconstructed by the hydraulic models which provided maximum water levels averaged on one cell which may not coincide with the exact location of the observations. Finally, modelling means a simplification of the processes, which implies cancelling the level variations due to some obstacles, such as cars, which are not simple to identify.In conclusion, both software packages can model a flood, even a flash flood, in an urbanised area. Research is still necessary to develop methods to fully use urban databases in order to define details more precisely. The improvements to the 1-D software should include a better modelling of storage and of crossroads with an integration of adapted relations for the head losses. 2-D software has a greater potential but the difficulty to build an optimal computational grid means a long computational time, which limits the use of such software to small areas. For both software packages, methods still need to be developed in order to represent exchanges with the sewage network, storage inside buildings and inputs directly coming from rainfall.
Keywords: Flash floods, urban risk, hydrodynamic modelling, de Saint Venant equations, october 1988 Nîmes flood, 1-D software, 2-D software, hydraulic jump
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