A Grid and Vehicle Density Prediction-Based Communication Scheme in Large-scale Urban Environments

2021 ◽  
Author(s):  
Bingyi Liu ◽  
Yang Sheng ◽  
Xun Shao ◽  
Yusheng Ji
Keyword(s):  
Large Scale ◽  
Urban Environments ◽  
Density Prediction ◽  
Vehicle Density ◽  
Communication Scheme

scholarly journals Joint Impacts of Drought and Habitat Fragmentation on Native Bee Assemblages in a California Biodiversity Hotspot

Insects ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 135
Author(s):  
Keng-Lou James Hung ◽  
Sara S. Sandoval ◽  
John S. Ascher ◽  
David A. Holway
Keyword(s):  
Habitat Fragmentation ◽  
Large Scale ◽  
Global Climate ◽  
Relative Magnitude ◽  
Urban Environments ◽  
Floral Resources ◽  
Severe Drought ◽  
Drought Event ◽  
Fragmented Habitat ◽  
Native Bee

Global climate change is causing more frequent and severe droughts, which could have serious repercussions for the maintenance of biodiversity. Here, we compare native bee assemblages collected via bowl traps before and after a severe drought event in 2014 in San Diego, California, and examine the relative magnitude of impacts from drought in fragmented habitat patches versus unfragmented natural reserves. Bee richness and diversity were higher in assemblages surveyed before the drought compared to those surveyed after the drought. However, bees belonging to the Lasioglossum subgenus Dialictus increased in abundance after the drought, driving increased representation by small-bodied, primitively eusocial, and generalist bees in post-drought assemblages. Conversely, among non-Dialictus bees, post-drought years were associated with decreased abundance and reduced representation by eusocial species. Drought effects were consistently greater in reserves, which supported more bee species, than in fragments, suggesting that fragmentation either had redundant impacts with drought, or ameliorated effects of drought by enhancing bees’ access to floral resources in irrigated urban environments. Shifts in assemblage composition associated with drought were three times greater compared to those associated with habitat fragmentation, highlighting the importance of understanding the impacts of large-scale climatic events relative to those associated with land use change.

The Use of Social Media for Urban Planning

2019 ◽  
pp. 1049-1070
Author(s):  
Fabian Neuhaus
Keyword(s):  
Social Media ◽  
Big Data ◽  
Urban Areas ◽  
Large Scale ◽  
Urban Environments ◽  
Data Systems ◽  
User Management ◽  
Social Nature ◽  
User Data ◽  
Use Of Social Media

User data created in the digital context has increasingly been of interest to analysis and spatial analysis in particular. Large scale computer user management systems such as digital ticketing and social networking are creating vast amount of data. Such data systems can contain information generated by potentially millions of individuals. This kind of data has been termed big data. The analysis of big data can in its spatial but also in a temporal and social nature be of much interest for analysis in the context of cities and urban areas. This chapter discusses this potential along with a selection of sample work and an in-depth case study. Hereby the focus is mainly on the use and employment of insight gained from social media data, especially the Twitter platform, in regards to cities and urban environments. The first part of the chapter discusses a range of examples that make use of big data and the mapping of digital social network data. The second part discusses the way the data is collected and processed. An important section is dedicated to the aspects of ethical considerations. A summary and an outlook are discussed at the end.

‘from a musical point of view, the world is musical at any given moment’: an interview with bill fontana

2005 ◽  
Vol 10 (2) ◽  
pp. 97-101 ◽  
Author(s):  
jøran rudi
Keyword(s):  
New York ◽  
New York City ◽  
York City ◽  
Large Scale ◽  
Urban Environments ◽  
Point Of View ◽  
Naturally Occurring ◽  
The World ◽  
American Composer ◽  
Brooklyn Bridge

bill fontana is an american composer and artist who has been working with large-scale sound installations since the 1970s. in his installations he recontextualises sounds by transmitting them from one location to another, and uses the transported sounds as acoustical ‘overlay’, masking the sounds naturally occurring in the installation spaces. his installations often occur in central urban environments, and he has, for example, been commissioned in conjunction with the fifty-year anniversary of d-day (1994, paris), and the 100-year anniversary of brooklyn bridge (1983, new york city).

scholarly journals On the Realistic Radio and Network Planning of IoT Sensor Networks

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3264 ◽  
Author(s):  
Loizos Kanaris ◽  
Charalampos Sergiou ◽  
Akis Kokkinis ◽  
Aris Pafitis ◽  
Nikos Antoniou ◽  
...  
Keyword(s):  
Large Scale ◽  
Open Systems ◽  
Urban Environments ◽  
Radio Propagation ◽  
Correct Usage ◽  
Open Systems Interconnection ◽  
Physical Information ◽  
Network Simulators ◽  
And Performance ◽  
Real Test

Planning and deploying a functional large scale Wireless Sensor Network (WSN) or a Network of Internet of Things (IoTs) is a challenging task, especially in complex urban environments. A main network design bottleneck is the existence and/or correct usage of appropriate cross layer simulators that can generate realistic results for the scenario of interest. Existing network simulators tend to overlook the complexity of the physical radio propagation layer and consequently do not realistically simulate the main radio propagation conditions that take place in urban or suburban environments, thus passing inaccurate results between Open Systems Interconnection (OSI) layers. This work demonstrates through simulations and measurements that, by correctly passing physical information to higher layers, the overall simulation process produces more accurate results at the network layer. It is demonstrated that the resulting simulation methodology can be utilized to accomplish realistic wireless planning and performance analysis of the deployed nodes, with results that are very close to those of real test-beds, or actual WSN deployments.

Flood management: Prediction of microbial contamination in large-scale floods in urban environments

2011 ◽  
Vol 37 (5) ◽  
pp. 1019-1029 ◽  
Author(s):  
Jonathon Taylor ◽  
Ka man Lai ◽  
Mike Davies ◽  
David Clifton ◽  
Ian Ridley ◽  
...  
Keyword(s):  
Large Scale ◽  
Microbial Contamination ◽  
Flood Management ◽  
Urban Environments

scholarly journals SPECIFICATION OF THE SOCIAL FORCE PEDESTRIAN MODEL BY EVOLUTIONARY ADJUSTMENT TO VIDEO TRACKING DATA

2007 ◽  
Vol 10 (supp02) ◽  
pp. 271-288 ◽  
Author(s):  
ANDERS JOHANSSON ◽  
DIRK HELBING ◽  
PRADYUMN K. SHUKLA
Keyword(s):  
Large Scale ◽  
Optimal Parameter ◽  
Video Tracking ◽  
Urban Environments ◽  
Force Model ◽  
Tracking Data ◽  
Social Force ◽  
Social Force Model ◽  
Video Recordings ◽  
The Social

Based on suitable video recordings of interactive pedestrian motion and improved tracking software, we apply an evolutionary optimization algorithm to determine optimal parameter specifications for the social force model. The calibrated model is then used for large-scale pedestrian simulations of evacuation scenarios, pilgrimage, and urban environments.

IMD: A Software Package for Molecular Dynamics Studies on Parallel Computers

1997 ◽  
Vol 08 (05) ◽  
pp. 1131-1140 ◽  
Author(s):  
J. Stadler ◽  
R. Mikulla ◽  
H.-R. Trebin
Keyword(s):  
Molecular Dynamics ◽  
Software Package ◽  
Large Scale ◽  
Md Simulation ◽  
Parallel Computers ◽  
Massively Parallel ◽  
Massively Parallel Computers ◽  
Communication Scheme ◽  
And Performance ◽  
Dynamics Simulations

We report on implementation and performance of the program IMD, designed for short range molecular dynamics simulations on massively parallel computers. After a short explanation of the cell-based algorithm, its extension to parallel computers as well as two variants of the communication scheme are discussed. We provide performance numbers for simulations of different sizes and compare them with values found in the literature. Finally we describe two applications, namely a very large scale simulation with more than 1.23×109 atoms, to our knowledge the largest published MD simulation up to this day and a simulation of a crack propagating in a two-dimensional quasicrystal.

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