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Considerations relating to the quality of underground water sources within the city of Barlad
M?D?LINA PAIU,SILVIU SUTEA-DRGAN,IULIANA GABRIELA BREAB?N
Cinq Continents , 2011,
Abstract: Considérations sur la qualité des sources d'eau souterraine dans la ville de Barlad. La ville de Barlad est alimenté avec l’eau potable qui provienne dans deux sources : souterraines et autres situées au surface. Aux derniers ans, la réduction de la longueur du réseau de distribution de l’eau dans la ville avec ~9%, a mené vers l’augmentation du nombre des utilisateurs de l’eau qui provienne de sources souterraines, c'est-à-dire les fontaines et les pompes, caractérises par une minéralisation haute. L’étude représente la première phase de l’étude qui veut mettre en évidence les variations imposées par la succession des saisons dans la région étudiée avecl’objectif de trouver les meilleures sources pour les habitants. Après récolter les échantillons d’eau, par les 44 sources souterraines, ont été déterminés les indicateurs de qualité de l’eau potable (en utilisant des méthodes électrochimiques, volumétriques et spectophotométriques). Puis les résultats ont été représentés avec ArcGis 9.3; en rélevant des dépassements pour certains indicateurs.
Multi-Scale Analysis of the Demographic Evolution in the Apuseni Mountains between 1880 and 2008
MAGDALENA DRGAN
Romanian Review of Regional Studies , 2010,
Abstract: In the following paper aims at studying the evolution of the population size in the Apuseni Mountains during 1880 – 2008, on different spatial scales. From the second half of the 20th century, the area has recorded a continual decrease of the demographic potential, accompanied by the deterioration of the age group structures because of the increase of the migratory effect. Following the same downward trend, different subregional evolutions determined by social and economic factors can be highlighted on the LAU1 scale (counties) and at the scale of three altitudinal-delimited areas (as the expression of the increasing limitations of natural agrarian factors). At the LAU2 scale (communes and towns), on the same decreasing trend, positive dynamic of the population appears in some towns of the area. However, we found the most diverse evolutions at the settlement level. In this study, we cover the demographic evolution of the villages that are commune centres and villages with population below 50 residents. Both categories highlight spatial and functional transformations that have occurred and are to take place in the rural mountains.
Disfavoured Zones and Tourist Areas in the Apuseni Mountains
MAGDALENA DRGAN
Romanian Review of Regional Studies , 2007,
Abstract: The transformations that have affected the region of the Apuseni Mountains after 1990, have determined a precarious economic and social status in the mining areas, a fact officially recognized through the delimitation of some “disfavoured zones”. The Apuseni Mountains are also a region with a very rich touristic potential, which led to the development of tourism in some of its parts. Yet, spatially, the two types of areas (disfavoured and touristic) do not overlap. Functionally, two different systems manifest themselves, separated by the Arie Valley and the planned development strategies tend to emphasize the already-appeared differences.
Disparities of the Medical-Sanitary Infrastructure in the North-West Development Region
DANIELA DRGAN
Romanian Review of Regional Studies , 2009,
Abstract: The present study proposes a systemic analysis which will determine the structure of inequalities, medical-sanitary disparities in the North-West Development Region. The methodological focus of our study falls on the medical-sanitary resources with a higher interest on the medical-sanitary infrastructure of this regional space. In order to highlight the “map” of the medical-sanitary disparities in the North-West Development Region we have operated an inventory of medical-sanitary resources and a demographical-based evaluation, thus coming to an outcome of a quantity-quality complex analysis.
ASPECTE ALE COMPORTAMENTULUI DEMOGRAFIC N MUN II APUSENI
MAGDALENA DRGAN
Geographia Napocensis , 2012,
Abstract: Aspects of the demographical behaviour in the Apuseni Mountains. Even though during the last 50 years in the Apuseni Mountains strong demographical decline occurred, regional differences appear in the spatial distribution of this phenomenon. The present study identifies several elements of the demographical behaviour that can explain those variations.
Development of a laminar boundary layer model for curved wall jets
Valeriu DRGAN
INCAS Bulletin , 2013, DOI: 10.13111/2066-8201.2013.5.2.3
Abstract: The paper addresses the issue of thin jets subjected to the Coand effect and in particular the boundary layer modeling. An existing semi-empirical Coand effect mathematical model is modified, with a more complex boundary layer model, in order to allow the estimative calculation of the detachment point and of other parameters such as friction coefficients, wall shear stress and the momentum and displacement integral thicknesses. The method used is analytical, based on the Rodman-Wood-Roberts model and the Pohlhausen boundary layer method. The work is significant for the pre-design calculations as well as for a quick checking of RANS CFD simulation results.
A novel divertless thrust vectoring nozzle using the countercirculation aerodynamic effect: Maximal Aerodynamic Yaw Actuator-MAYA
Valeriu DRGAN
INCAS Bulletin , 2011, DOI: 10.13111/2066-8201.2011.3.1.6
Abstract: During the second half of the 20th century, Henri Coanda had extensively studied theCoanda effect and also it’s application for high lift devices that use –in one way or another- supercirculation. A previous work has been done for using the Coanda effect to generate perpendicularforces to the aircraft trajectory– including aircraft specifically designed to attain short take off suchas the An-72 and YC-14.Dwelling on the same principles, the author had tried to imagine and test a 2D thrust vectoring deviceusing differentiated super circulation on two flat surfaces placed near the jet exhaust. The success ofthis endeavor has been limited because the forces produced were not as great as anticipated.However, the numerical simulations indicated the presence of another, opposite effect, more powerfuland potentially more useful than the first: the counter circulation.This paper describes the working principles of a two dimensional thrust vectoring nozzle aimingsatisfy the need for a conventional rudder to control yaw and also shows the prospect of upgrading itto a 3D thrust vectoring nozzle.
A New Mathematical Model for Coanda Effect Velocity Approximation
Valeriu DRGAN
INCAS Bulletin , 2012, DOI: 10.13111/2066-8201.2012.4.4.7
Abstract: This paper addresses the problem of obtaining a set of mathematical equations that can accurately describe the velocity flow field near a cylindrical surface influenced by the Coand effect. The work is relevant since the current state of the art Reynolds Averaged Navier Stokes models with curvature correction do not completely describe the properties of the flow in accordance with the experimental data. Semi-empirical equations are therefore deduced based on experimental and theoretical state of the art. The resulting model is validated over a wider range of geometric layouts than any other existing semi-empirical model of its kind. The applications of this model are numerous, from super circulation wing calculations to fluidic devices such as actuators or fluidic diodes.
A novel hovering type of fixed wing aircraft with stealth capability
Valeriu DRGAN
INCAS Bulletin , 2010, DOI: 10.13111/2066-8201.2010.2.4.13
Abstract: The tactical need for fixed wing aircraft with hovering capably has long been recognized bythe military for two reasons: increased safety when landing on aircraft carriers and higher velocitiesthat the ones obtainable with rotary wing aircraft.Thus far, the only concept governing the field of vertical flight was to use thrust either from a liftfan-F35, puffer ducts –Harrier or smaller jet engines-D0 31 or Yak-141, i.e. direct lift thrust.In this paper we will look at the prospect of using a combination of the Coanda effect with theVenturi effect to generate lift by so- called “supercirculation”. This novel approach can yield manyadvantages to conventional vertical lifting by providing a more stable platform and requiring lowerpower settings – and thus lower fuel consumption.The aircraft has a fixed, negatively sweped wing that uses circulation control to achieve lift atzero air speed. The fluid used for supercirculation will come from the fan thrust reversers – which, ifcorrectly managed, can give a sufficient flow for lifting the craft and also a negative thrust componentto compensate for the positive thrust of the primary flow (not diverted).
Impact of Secondary Residences on the Rural Space of the Gil u-Muntele Mare Mountains
MAGDALENA DRGAN
Romanian Review of Regional Studies , 2009,
Abstract: The increasing in the number of secondary residences is a phenomenon which has affected the rural space of Romania after 1990, especially in the mountain area. In order to emphasize its impact, the present paper studies the case of villages in the Gil u-Muntele Mare Mountains. By studying the bibliography and the statistical data we got the general picture of this case and by interviewing regional and local authorities the real extent of the matter revealed. It resulted that in this area, secondary residences phenomena led to spatial and functional impact upon rural space and to social and economic consequences on local communities: secondary residences transform rural space into one with tourist characteristics: implantation of a suite of secondary residences, the local councils collect more taxes but also deal with overwhelmed facilities and pollution, while the native people copy a different lifestyle. In some cases, ownership transfer towards city residents or the small villages taken over by non-resident people speak of the extreme transformation of the rural space.
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