655 research outputs found
The impact of the new airport of Athens on the land values of Eastern Attica
The analysis of the value of the area around "Eleftherios Venizelos", the new airport in Greater Athens area has been based on a survey of the international experience and followed by a quantitative data analysis. The figures of the database come from the Objective System of Assessment (O.S.A.) as well as the Relative Price System of the Local Revenue Offices (R.P.S.R.O.). The data was analysed according to the hierarchical tree method and there has been a detailed reference to the restrictions and the conditions of the data use. The analysis has been at a horizontal level, that is, we have tried to interpret the increasing decline between the O.S.A. or the R.P.S.R.O. prices and the real prices of land The ranking system has been based on the functionality of the specific areas. The analysis has been at a vertical level too, that is, a year by year analysis of the built-up areas which have been grouped geographically. These built-up areas come under the O.S.A. and R.P.S.R.O. systems. The analysis also, determines the perspective on the land use pattern of the study area.
Generalized h-index for Disclosing Latent Facts in Citation Networks
What is the value of a scientist and its impact upon the scientific thinking?
How can we measure the prestige of a journal or of a conference? The evaluation
of the scientific work of a scientist and the estimation of the quality of a
journal or conference has long attracted significant interest, due to the
benefits from obtaining an unbiased and fair criterion. Although it appears to
be simple, defining a quality metric is not an easy task. To overcome the
disadvantages of the present metrics used for ranking scientists and journals,
J.E. Hirsch proposed a pioneering metric, the now famous h-index. In this
article, we demonstrate several inefficiencies of this index and develop a pair
of generalizations and effective variants of it to deal with scientist ranking
and with publication forum ranking. The new citation indices are able to
disclose trendsetters in scientific research, as well as researchers that
constantly shape their field with their influential work, no matter how old
they are. We exhibit the effectiveness and the benefits of the new indices to
unfold the full potential of the h-index, with extensive experimental results
obtained from DBLP, a widely known on-line digital library.Comment: 19 pages, 17 tables, 27 figure
Enhanced optical conductivity and many-body effects in strongly-driven photo-excited semi-metallic graphite
The excitation of quasi-particles near the extrema of the electronic band
structure is a gateway to electronic phase transitions in condensed matter. In
a many-body system, quasi-particle dynamics are strongly influenced by the
electronic single-particle structure and have been extensively studied in the
weak optical excitation regime. Yet, under strong optical excitation, where
light fields coherently drive carriers, the dynamics of many-body interactions
that can lead to new quantum phases remain largely unresolved. Here, we induce
such a highly non-equilibrium many-body state through strong optical excitation
of charge carriers near the van Hove singularity in graphite. We investigate
the system's evolution into a strongly-driven photo-excited state with
attosecond soft X-ray core-level spectroscopy. Surprisingly, we find an
enhancement of the optical conductivity of nearly ten times the quantum
conductivity and pinpoint it to carrier excitations in flat bands. This
interaction regime is robust against carrier-carrier interaction with coherent
optical phonons acting as an attractive force reminiscent of superconductivity.
The strongly-driven non-equilibrium state is markedly different from the
single-particle structure and macroscopic conductivity and is a consequence of
the non-adiabatic many-body state
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The Hypanis fluvial deltaic system in Xanthe Terra: a candidate ExoMars 2018 Rover landing site
The search for life on Mars is a cornerstone of international solar system exploration. In 2018, the European Space agency will launch the ExoMars Rover to further this goal. The key science objectives of the ExoMars Rover are to: 1) search for signs of past and present life on Mars; 2) investigate the water/geochemical environment as a function of depth in the shallow subsurface; and 3) to characterize the surface environment. ExoMars will drill into the sub-surface to look for indicators of past life using a variety of complementary techniques, including assessment of morphology (potential fossil organisms), mineralogy (past environments) and a search for organic molecules and their chirality (biomarkers).
The choice of landing site is vital if the objectives are to be met. The landing site must: (i) be ancient (≥3.6 Ga); (ii) show abundant morphological and mineral evidence for long-term, or frequently reoccurring, aqueous activity; (iii) include numerous sedimentary outcrops that (iv) are distributed over the landing region (the typical Rover traverse range is a few km, but ellipse size is ~ 104 by 19 km). Various ‘engineering constraints’ also apply, including: (i) latitude limited to 5º S to 25º N; (ii) maximum altitude of the landing site 2 km below Mars’s datum; and (iii) few steep slopes within the ellipse
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