There are four shelf-incising submarine canyons off SW Taiwan. They are distributed along the active continental margin, which is periodically flushed by gravity flows. Shelf-incising canyons, such as Kaoping Canyon, may not only be affected by ocean...
This article introduces a novel algorithm for automatic extraction of canyons which was developed in the Department of the Remote Sensing and Land Information Systems at the University of Freiburg (FELIS). The algorithm detects canyons by means of us...
As an important part of road transportation, bridge engineering plays a pivotal role in infrastructure construction. The wind field characteristics of the bridge site area have an essential influence on both the construction and operation period of t...
This study aimed to evaluate the wind environment in step-up and step-down urban canyons through a computational numerical experiment using the computational fluid dynamics (CFD) model. Spatial structural conditions were considered according to the l...
The air quality in a street canyon seriously affects the exposure level of pollutants for pedestrians and is directly related to the indoor air quality (IAQ) of surrounding buildings. In order to improve the street canyon environment, it is necessary...
Outdoor thermal comfort is one of the essential characteristics of effective urban planning. The aspect ratio and orientation of the street canyon influence the thermal performance. Regulations standardize construction rules without accounting for re...
This paper carried out laboratory experiments to study evolution of internal solitary waves (ISWs) over submarine canyons with a combination of PIV (particle image velocimetry) and PLIF (planar laser-induced fluorescence) techniques. Taking canyon an...
Numerical simulations are conducted to investigate the near-bed flow behaviors of submarine canyons with periodic ridge-valley topography on continental slopes. In the numerical simulation, two topographic parameters are defined: α represents t...
We created a new, 100 m horizontal resolution bathymetry raster and used it to define 29 canyons of the eastern Bering Sea (EBS) slope area off of Alaska, USA. To create this bathymetry surface we proofed, edited, and digitized 18 million soundings f...
Few studies identify potential hazards affecting canyoning. This activity has an increasing number of practitioners, and hence, a greater number of people are affected by potential natural hazards. Mountain rivers are located in places subject to sev...
Traffic-related air pollution in street canyons can cause health problems for pedestrians. In order to clarify the behavior of reactive pollutants, such as NOx and O3, in street canyons, a computational fluid dynamics (CFD) model coupled with a chemi...
Cities in the last century have been suffering from the disorderly and unplanned growth of urban centers. Consequently, innumerable environmental problems started to plague these regions, one of them is the alteration of the surface temperature throu...
The measurement of globe temperature (GT) is essential for investigating pedestrian thermal comfort in street canyons. The globe thermometer is the most common instrument used to measure GT; however, its application in scale models has not been thoro...
In this study, we have developed a numerical model based on an open source Computational Fluid Dynamics (CFD) package OpenFOAM, in order to investigate the flow pattern and pollutant dispersion in urban street canyons with different geometry configur...
The measurement and analysis of the spatial attributes of the street canyon hold significant importance in the advancement of photovoltaic integrated shading devices (PVSDs). This study offers the space aspect ratio index AR(h) as a more efficient me...
During the Last Glacial Maximum (LGM) (~20,000 years ago), the sea level was lower than that during the present day by 120 m and the heads of most submarine canyons were close or connected to the coastline or shore, with enhanced terrestrial sediment...
Bottom trawling in submarine canyons can affect their sedimentary dynamics, but studies addressing this topic are still scarce. In the Gulf of Palermo (NW Sicily, SW Mediterranean Sea), bottom trawling occurs on the continental slope, but principally...
This study presents a computational fluid dynamics (CFD) modeling framework to simulate two-phase (liquid and gas) chemical agent dispersion in urban canyons. The model was validated against wind tunnel experiments, meeting statistical criteria. To a...
The sedimentary dynamics and geological evolution of the Naples canyons during the Late Quaternary have been studied based on sedimentological and seismo-stratigraphic data. Several factors, including the sedimentary environments, tectonic setting, a...
High concentrations of ozone (O3) is a major air problem in urban areas, which creates a serious threat to human health. Urban street canyon morphology plays a key role in air pollutant dispersion and photochemical reaction rate. In this study, a one...
Velocity measurements and simulations in an idealized urban environment were studied, focusing on turbulent flow over street canyons. Time series of fluctuating velocities were considered as marked point processes, and the distribution of mean reside...
The pedestrian wind environment in a street canyon is affected by a multitude of factors, including the height and geometric shape of the surrounding buildings, the street width, the wind direction, and speed. Wind-tunnel tests were performed to dete...
The residential block is the cognitive unit for residents to constitute urban imagery. As one of the most frequently used urban outdoor public spaces by residents, the thermal comfort of street canyons is an essential indicator for assessing sustaina...
Trees are known to modify radiation on building façades via shading effects. However, the combined influence of tree morphological traits and street canyon geometry on façade solar exposure remains inadequately quantified. This paper wi...
Air pollution in urban street canyons presents a serious health risk, especially in densely populated areas. While previous research has explored airflow characteristics in these canyons, it often lacks detailed data on pollutant dispersion and the e...
In this study, the effect of seasonal variation on air flow and pollutant dispersion characteristics was numerically investigated. A three-dimensional urban canopy model with unit aspect ratio (H/D = 1) was used to calculate surface temperature distr...
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This study investigated smoke dispersion inside a street canyon in a series of numerical simulations. The building height and street width as well as the cross-wind velocity were changed during the simulation, and the smoke recirculation behavior ins...
To reduce energy demand (both fossil fuel and renewable energy) for cooling the urban heat island environment, some solutions have been studied. Among these methods, the water spray system is considered more flexible due to its dynamic controls. This...
Modeling solar radiation in street canyons is crucial to understanding the solar availability of building façades. This article describes the implementation of a simulation routine, developed in the Matlab® computer language, which is aimed at predic...
A validated standard k-ε model was used to investigate the effects of ground heating on ventilation and pollutant transport in a three-dimensional (3D) street canyon. Air entered the street canyon from the upper regions of side surfaces and m...
With the rapid development of cities and the rapid increase in automobile ownership, traffic has become one of the main sources of PM2.5 pollution, which can be reduced by road greening through sedimentation, blocking, adhesion, and absorption. Using...
Street canyons are basic components of modern cities. Sound propagation in streets has been proven to be significantly affected by reflections from building façades. In this paper, an iterative model combining acoustic radiosity and the image...
Air pollution is a major health hazard for the population that increasingly lives in cities. Street-scale Air Quality Models (AQMs) are a cheap and efficient way to study air pollution and possibly provide solutions. Having to include all the complex...
In recent years, the impact of surface heat islands in urban street canyons has become increasingly apparent. However, the research on the use of trees to mitigate surface heat islands remains limited. To address this gap, this study combines experim...
The Reynolds-averaged Navier-Stokes (RANS) model and revised generalized drift flux model were used to investigate the characteristics of airflow fields and PM2.5 dispersion in street canyons with a variety setting on tree crown morphologies (i.e., c...
Constantly changing vehicle stock, modification of road infrastructure, and other conditions result in a need to update the knowledge on the effectiveness of individual traffic management strategies, which could form the basis for actions taken by lo...
Because motor vehicles emit a large amount of PM2.5 pollution, traffic-related emissions have always been an important part of PM2.5 pollution. To better understand the influence of street trees on traffic-related PM2.5 pollution, our study focused o...
This research aims to solve the safe navigation problem of autonomous underwater vehicles (AUVs) in deep ocean, which is a complex and changeable environment with various mountains. When an AUV reaches the deep sea navigation, it encounters many unde...
Hong Kong is a typical high-density city in a subtropical climate region, and deep street canyons are among the main features of its urban planning. How the urban geometry influences the urban thermal environment in this city has become a hot topic t...
Previous gas hydrate production tests conducted by the Guangzhou Marine Geological Survey (GSGM) in 2017 and 2020 indicated the great potential of gas hydrates in the Shenhu Sea area in the Pearl River Mouth Basin (PRMB), China. In this study, the ef...
This paper examines the propagation of radio waves in so-called urban street canyons through formulations based on Geometrical Optics (GO) and the Uniform Theory of Diffraction (UTD). As this type of environment comprises a street flanked by tall bui...
To examine the effect of green roofs (GRs) and green walls (GWs) on coarse particle (PM10) dispersion in urban street canyons, a computational fluid dynamics (CFD) simulation was conducted with a Reynolds-averaged Navier-Stokes (RANS) model and a rev...
Extreme heat exposure has severe negative impacts on humans, and the issue is exacerbated by climate change. Estimating spatial heat stress such as mean radiant temperature (MRT) is currently difficult to apply at city scale. This study constructed a...
In the central Mesa Verde region, rock art occurs on canyon walls and on boulders that are frequently associated with other archaeological remains. Moreover, rock art, together with architecture and pottery, is actually a primary source of archaeolog...
Heterogeneous airground robotic systems, which integrate unmanned ground vehicles and unmanned aerial vehicles, have shown significant potential in complex autonomous missions. However, when deployed in urban canyons, dense high-rise buildings impose...
We propose a comprehensive literature review based on big data and V2X research to find promising tools to detect vehicles for traffic research and provide safe autonomous vehicle (AV) traffic. Presented data sources can provide real-time data for V2...
Air pollution, such as particulate matter (PM), and extreme weather are causing increasingly complex problems and socioeconomic damage in urban environments year-round. This study predicts extreme weather and air pollution changes that occur in urban...
Steep submarine canyons pose challenges to deep-water pipeline routing because of rugged terrain and slide-related hazards. This study integrates 3D seismic data, shipborne and autonomous underwater vehicle bathymetry, sub-bottom profiles, sediment t...
Urban environments present substantial obstacles to GPS positioning accuracy, primarily due to multipath interference and limited satellite visibility. To address these challenges, we propose a novel weighting approach, referred to as the HK model, t...
In this study, we analyzed the spatiotemporal characteristics of pedestrian behavior in street spaces using pedestrian count data—specifically, the number of pedestrians passing in front of infrared sensors installed throughout the downtown are...
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