GIS Analyses and Maps Creation of a Naturalistic Area: The Carengione Oasis

This paper describes the experience carried out with the aim to provide a technical and geo-referenced contribution to a project, submitted to the Common of Peschiera Borromeo in the Province of Milan in Lombardy. The promoter is a group of local associations;the aim is the valorisation and fruition of a green area, named Carengione Oasis. At first a GIS pre-analysis of the area has been performed to achieve a thorough knowledge of the area object of study. Then, a handheld GSP navigator has been employed to collect the data to be processed in a GIS software. This device choice has pros (a fast and very easy survey has been carried out) and cons (the acquired data have a precision of 3 to 5 meters). These data have been processed with the aid of the GIS software ArcMap release 10.4.1 by Esri. Also some free aerial images have been employed to edit features inaccessible on site. The achieved results are some thematic, metric and georeferenced maps and also a 3D virtual tour for a realistic visit of this area. They fulfil the project requirements. Anyway, due to their low precision, they have not been uploaded to enrich the official Lombardy cartography (DBTR);for this reason, part of them has been donated to the free data interchange OpenStreetMap. This work could be considered as a first step for future more precise surveys which would allow adding the acquired results to the DBTR;it has also been planned to create a story map describing the experience illustrated in this paper.

Prospects for measuring dark energy with 21 cm intensity mapping experiments:A joint survey strategy

The 21 cm intensity mapping(IM)technique provides us with an efficient way to observe the cosmic large-scale structure(LSS).From the LSS data,one can use the baryon acoustic oscillation and redshift space distortion to trace the expansion and growth history of the universe,and thus measure the dark energy parameters.In this paper,we make a forecast for cosmological parameter estimation with the synergy of three 21 cm IM experiments.Specifically,we adopt a novel joint survey strategy,FAST(0<z<0.35)+SKA1-MID(0.35<z<0.8)+HIRAX(0.8<z<2.5),to measure dark energy.We simulate the 21 cm IM observations under the assumption of excellent foreground removal.We find that the synergy of three experiments could place quite tight constraints on cosmological parameters.For example,it providesσ(?m)=0.0039 andσ(H0)=0.27 km s^(-1) Mpc^(-1) in theΛCDM model.Notably,the synergy could break the cosmological parameter degeneracies when constraining the dynamical dark energy models.Concretely,the joint observation offersσ(w)=0.019 in the wCDM model,andσ(w0)=0.085 andσ(wa)=0.32 in the w0waCDM model.These results are better than or equal to those given by CMB+BAO+SN.In addition,when the foreground removal efficiency is relatively low,the strategy still performs well.Therefore,the 21 cm IM joint survey strategy is promising and worth pursuing.