scholarly journals Solar Access Assessment in Dense Urban Environments: The Effect of Intersections in an Urban Canyon

Energies ◽  
2016 ◽  
Vol 9 (10) ◽  
pp. 796 ◽  
Author(s):  
Elena Garcia-Nevado ◽  
Anna Pages-Ramon ◽  
Helena Coch
2020 ◽  
Vol 12 (11) ◽  
pp. 1724
Author(s):  
Alfred Mayalu ◽  
Kevin Kochersberger ◽  
Barry Jenkins ◽  
François Malassenet

This paper introduces a novel protocol for managing low altitude 3D aeronautical chart data to address the unique navigational challenges and collision risks associated with populated urban environments. Based on the Open Geospatial Consortium (OGC) 3D Tiles standard for geospatial data delivery, the proposed extension, called 3D Tiles Nav., uses a navigation-centric packet structure which automatically decomposes the navigable regions of space into hyperlocal navigation cells and encodes environmental surfaces that are potentially visible from each cell. The developed method is sensor agnostic and provides the ability to quickly and conservatively encode visibility directly from a region by enabling an expanded approach to viewshed analysis. In this approach, the navigation cells themselves are used to represent the intrinsic positional uncertainty often needed for navigation. Furthermore, we present in detail this new data format and its unique features as well as a candidate framework illustrating how an Unmanned Traffic Management (UTM) system could support trajectory-based operations and performance-based navigation in the urban canyon. Our results, experiments, and simulations conclude that this data reorganization enables 3D map streaming using less bandwidth and efficient 3D map-matching systems with limited on-board compute, storage, and sensor resources.


2013 ◽  
Vol 2013 ◽  
pp. 1-16
Author(s):  
Mark G. Petovello ◽  
Kyle O'Keefe ◽  
Phil Wei ◽  
Chaminda Basnayake

Vehicle-to-vehicle relative navigation of a network of vehicles travelling in an urban canyon is assessed using least-squares and Kalman filtering covariance simulation techniques. Between-vehicle differential GPS is compared with differential GPS augmented with between-vehicle ultrawideband range and bearing measurements. The three measurement types are combined using both least-squares and Kalman filtering to estimate the horizontal positions of a network of vehicles travelling in the same direction on a road in a simulated urban canyon. The number of vehicles participating in the network is varied between two and nine while the severity of the urban canyon was varied from 15-to 65-degree elevation mask angles. The effect of each vehicle’s azimuth being known a priori, or unknown is assessed. The resulting relative positions in the network of vehicles are then analysed in terms of horizontal accuracy and statistical reliability of the solution. The addition of both range and bearing measurements provides protection levels on the order of 2 m at almost all times where DGPS alone only rarely has observation redundancy and often exhibits estimated accuracies worse than 200 m. Reliability is further improved when the vehicle azimuth is assumed to be known a priori.


1990 ◽  
Vol 14 (2) ◽  
pp. 117-131 ◽  
Author(s):  
A.J. Arnfield

2010 ◽  
Vol 63 (4) ◽  
pp. 681-693 ◽  
Author(s):  
Shengyue Ji ◽  
Wu Chen ◽  
Xiaoli Ding ◽  
Yongqi Chen ◽  
Chunmei Zhao ◽  
...  

With the existing GPS, the replenishment of GLONASS and the launching of Galileo there will be three satellite navigation systems in the future, with a total of more than 80 satellites. So it can be expected that the performance of the global navigation satellite system (GNSS) will be greatly improved, especially in urban environments. This paper studies the potential benefits of GPS/GLONASS/Galileo integration in an urban canyon – Hong Kong. The navigation performances of four choices (GPS alone, GPS+GLONASS, GPS+Galileo and GPS+GLONASS+Galileo) are evaluated in terms of availability, coverage, and continuity based on simulation. The results show that there are significant improvements in availability, coverage and continuity, by using GPS+GLONASS+Galileo compared with the other choices. But the performance is still not good enough for most navigation applications in urban environments.


2014 ◽  
Author(s):  
Chrono Nu ◽  
Katie Mullin ◽  
Hailey Edwards ◽  
Kailey Kornhauser ◽  
Russell Costa ◽  
...  

TERRITORIO ◽  
2020 ◽  
pp. 148-163
Author(s):  
Luca Fondacci

In the 1970s, the fragile historical centre of the city of Perugia was a key area where the binomial of sustainable mobility and urban regeneration was developed and applied. At the turn of the xxi century, the low carbon automatic people-mover Minimetrò broadened that application from the city's historical centre to the outskirts, promoting the enhancement of several urban environments. This paper is the outcome of an investigation of original sources, field surveys and direct interviews, which addresses the Minimetrò as the backbone of a wide regeneration process which has had a considerable impact on the economic development of a peripheral area of the city which was previously devoid of any clear urban sense. The conclusion proposes some solutions to improve the nature of the Minimetrò as an experimental alternative means of transport.


Sign in / Sign up

Export Citation Format

Share Document