Air Corridors: Concept, Design, Simulation, and Rules of Engagement

Air corridors are an integral part of the advanced air mobility infrastructure. They are the virtual highways in the sky for the transportation of people and cargo in a controlled airspace at an altitude of around 1000 ft. to 2000 ft. above ground level. These corridors will be utilized by (unmanned) air taxis, which will be deployed in rural and metropolitan regions to carry passengers and freight, as well as air ambulances, which will be deployed to offer first responder services such as 911 emergencies. This paper presents fundamental insights into the design of air corridors with high operational efficiency as well as zero collisions. It begins with the definitions of air cube, skylane or track, intersection, vertiport, gate, and air corridor. Then a multi-layered air corridor model is proposed. Traffic at intersections is analyzed in detail with examples of vehicles turning in different directions. The concept of capacity of an air corridor is introduced along with the nature of distribution of locations of vehicles in the air corridor and collision probability inside the corridor are discussed. Finally, results of traffic flow simulations are presented.

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Air Corridors: Concept, Design, Simulation, and Rules of Engagement

10.20944/preprints202109.0232.v1 ◽

2021 ◽

Author(s):

Sabrina Islam Muna ◽

Srijita Mukherjee ◽

Kamesh Namuduri ◽

Marc Compere ◽

M. Ilhan Akbas ◽

...

Keyword(s):

Ground Level ◽

Operational Efficiency ◽

Collision Probability ◽

Concept Design ◽

Traffic Flows

Air corridors are an integral part of the advanced air mobility infrastructure. They are the virtual highways in the sky for transportation of people and cargo in the controlled airspace at an altitude of around 1000 ft. to 2000 ft. above the ground level. This paper presents fundamental insights into the design of air corridors with high operational efficiency as well as zero collisions. It begins with the definitions of air cube, skylane or track, intersection, vertiport, gate, and air corridor. Then, a multi-layered air corridor model is proposed. Traffic at intersections is analyzed in detail with examples of vehicles turning in different directions. The concept of capacity of an air corridor is introduced along with the nature of distribution of locations of vehicles in the air corridor and collision probability inside the corridor are discussed. Finally, the results of simulations of traffic flows are presented.

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Spatial Analysis (Measurements at Heights of 10 m and 20 m above Ground Level) of the Concentrations of Particulate Matter (PM10, PM2.5, and PM1.0) and Gaseous Pollutants (H2S) on the University Campus: A Case Study

Atmosphere ◽

10.3390/atmos12010062 ◽

2021 ◽

Vol 12 (1) ◽

pp. 62

Author(s):

Robert Cichowicz ◽

Maciej Dobrzański

Keyword(s):

Spatial Distribution ◽

Hydrogen Sulfide ◽

Particulate Matter ◽

Air Quality ◽

Spatial Analysis ◽

Ground Level ◽

Leeward Side ◽

High Concentration ◽

Above Ground Level ◽

High Concentrations

Spatial analysis of the distribution of particulate matter PM10, PM2.5, PM1.0, and hydrogen sulfide (H2S) gas pollution was performed in the area around a university library building. The reasons for the subject matter were reports related to the perceptible odor characteristic of hydrogen sulfide and a general poor assessment of air quality by employees and students. Due to the area of analysis, it was decided to perform measurements at two heights, 10 m and 20 m above ground level, using measuring equipment attached to a DJI Matrice 600 unmanned aerial vehicle (UAV). The aim of the measurements was air quality assessment and investigate the convergence of the theory of air flow around the building with the spatial distribution of air pollutants. Considerable differences of up to 63% were observed in the concentrations of pollutants measured around the building, especially between opposite sides, depending on the direction of the wind. To explain these differences, the theory of aerodynamics was applied to visualize the probable airflow in the direction of the wind. A strong convergence was observed between the aerodynamic model and the spatial distribution of pollutants. This was evidenced by the high concentrations of dust in the areas of strong turbulence at the edges of the building and on the leeward side. The accumulation of pollutants was also clearly noticeable in these locations. A high concentration of H2S was recorded around the library building on the side of the car park. On the other hand, the air turbulence around the building dispersed the gas pollution, causing the concentration of H2S to drop on the leeward side. It was confirmed that in some analyzed areas the permissible concentration of H2S was exceeded.

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A Climatology of Nocturnal Low-Level Jets at Cabauw

Journal of Applied Meteorology and Climatology ◽

10.1175/2009jamc1965.1 ◽

2009 ◽

Vol 48 (8) ◽

pp. 1627-1642 ◽

Cited By ~ 101

Author(s):

P. Baas ◽

F. C. Bosveld ◽

H. Klein Baltink ◽

A. A. M. Holtslag

Keyword(s):

Wind Speed ◽

Ground Level ◽

Geostrophic Wind ◽

Stable Stratification ◽

Radiative Cooling ◽

Inertial Oscillation ◽

Stable Boundary Layers ◽

Above Ground Level ◽

Low Level ◽

Low Level Jets

Abstract A climatology of nocturnal low-level jets (LLJs) is presented for the topographically flat measurement site at Cabauw, the Netherlands. LLJ characteristics are derived from a 7-yr half-hourly database of wind speed profiles, obtained from the 200-m mast and a wind profiler. Many LLJs at Cabauw originate from an inertial oscillation, which develops after sunset in a layer decoupled from the surface by stable stratification. The data are classified to different types of stable boundary layers by using the geostrophic wind speed and the isothermal net radiative cooling as classification parameters. For each of these classes, LLJ characteristics like frequency of occurrence, height above ground level, and the turning of the wind vector across the boundary layer are determined. It is found that LLJs occur in about 20% of the nights, are typically situated at 140–260 m above ground level, and have a speed of 6–10 m s−1. Development of a substantial LLJ is most likely to occur for moderate geostrophic forcing and a high radiative cooling. A comparison with the 40-yr ECMWF Re-Analysis (ERA-40) is added to illustrate how the results can be used to evaluate the performance of atmospheric models.

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Pruning intensity and amino acids tryptophan and glycine on growth and flowering of Jasminum sambac

Ornamental Horticulture ◽

10.1590/2447-536x.v27i1.2231 ◽

2021 ◽

Vol 27 (1) ◽

pp. 20-25

Author(s):

Ziyad Khalf Salih ◽

Seyedeh Somayyeh Shafiei Masouleh ◽

Mohamed Abdulla Ahmed ◽

Marwan Abdulla Sanam

Keyword(s):

Amino Acids ◽

Essential Oil ◽

Foliar Application ◽

Ground Level ◽

Growth And Yield ◽

Reproductive Growth ◽

Above Ground Level ◽

Evergreen Shrub ◽

Jasminum Sambac ◽

Pruning Intensity

Abstract Jasmine (Jasminum sambac L.) is an evergreen shrub and very fragrant, which has a very importance in the perfume industry and its flowers are used in different religious and ceremonies. Training the shrubs for more yields of flowers and essential oil with horticultural improvement effects of pruning and amino acids may help gardeners to achieve more benefits. This study aimed to investigate the effects of pruning intensity (without pruning, 40, 60 or 75 cm above ground level) and foliar application of amino acids (without amino acids, tryptophan or glycine) on jasmine shrubs for promoting growth and reproductive growth and the content of essential oil. The results showed that plants with light pruning (75 cm) and foliar application of amino acids especially glycine had the best growth and yield, which means that plants were affected by the interactions of pruning level and application of amino acids.

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Development and application of a new mobile LOPAP instrument for the measurement of HONO altitude profiles in the planetary boundary layer

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-2-2027-2009 ◽

2009 ◽

Vol 2 (4) ◽

pp. 2027-2054 ◽

Cited By ~ 20

Author(s):

R. Häseler ◽

T. Brauers ◽

F. Holland ◽

A. Wahner

Keyword(s):

Nitrous Acid ◽

Ground Level ◽

Concentration Profiles ◽

Mixing Ratio ◽

Above Ground Level ◽

Mixing Ratios ◽

New Instrument ◽

Mobile Measurements ◽

Southwest Germany ◽

Absorption Technique

Abstract. The LOPAP (long path absorption) technique has been shown to be very sensitive for the detection of nitrous acid (HONO) in the atmosphere. However, current instruments were mainly built for ground based applications. Therefore, we designed a new LOPAP instrument to be more versatile for mobile measurements and to meet the requirements for airborne application. The detection limit of the new instrument is below 1 ppt at a time resolution of 5 to 7 min. As a first test, the instrument was successfully employed during the ZEPTER-1 campaign in July 2007 on board of the Zeppelin NT airship. During 15 flights on six days we measured HONO concentration profiles over southwest Germany, predominantly in the range between 100 m and 650 m above ground level. On average, a mixing ratio of 34 ppt was observed, almost independently of height. Within a econd campaign, ZEPTER-2 in fall 2008, higher HONO mixing ratios were observed in the Lake Constance area.

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UAV high-resolution magnetic mapping of the Chenaillet ophiolite, in the Alps

10.5194/egusphere-egu21-7050 ◽

2021 ◽

Author(s):

Pauline Le Maire ◽

Denis Thieblemont ◽

Marc Munschy ◽

Guillaume Martelet ◽

Geoffroy Mohn

Keyword(s):

Magnetic Field ◽

Ground Level ◽

Weather Conditions ◽

Geological Mapping ◽

Magnetic Data ◽

Magnetic Survey ◽

Magnetic Signal ◽

Alpine Orogeny ◽

Above Ground Level ◽

Slow Spreading

Continent-Ocean Transitions (COT) and ultra-slow spreading ridges, floored by wide area of exhumed serpentinized mantle, bear strong amplitude magnetic lineations. However, whether these anomalies are linked to inversions of the direction of the magnetization (therefore characterized as isochrones of seafloor spreading) or to structural and lithological contrasts remains an open question. Generally, marine magnetic data acquired at sea surface along profiles, are too low resolution to image the intensity variations of the magnetic field at a kilometric scale. Performing a dense deep tow magnetic survey at a present-day COT or ultra-slow spreading system would be better to determine the sources of the magnetic signal but remains expensive. To go ahead, a valuable alternative to address these questions is to record the magnetic signal on ophiolite representing remnants of COT and oceanic systems sampled in orogenic system. We worked on the Chenaillet Ophiolite (French Alps), which represents a fossil COT or ultra-slow spreading system integrated to the Alpine orogeny. This ophiolite escaped high-pressure metamorphism and has only been weakly deformed during Alpine orogeny, preserving its pre-orogenic structure.We performed an UAV magnetic survey using fluxgate magnetometers in complex conditions due to the altitude (> 1800 m), the strong topography variations and the weather conditions (negative temperatures, snow). Despite these difficulties, which highlight the viability of UAV for geophysical measurements, a survey of 20 square kilometers with 219 km of profiling was completed 100 m above ground level. Flight line spacing is 100 m above the ophiolitic basement and 200 m above the sedimentary units. Another magnetic UAV survey was flown with another UAV to map a small area 10 m above ground level. Magnetic anomaly maps were computed after standard processing (e.g., calibration/compensation, temporal variation and regional magnetic field corrections, levelling).Our first results evidence well-defined magnetic anomalies clearly linked to serpentinite. This shows that the magnetic signal is of sufficient resolution to contribute to a revision of the cartography of the massif combining geological observations and magnetic data.In addition, the magnetic susceptibility was measured on 60 outcrops, to support interpretation.In this presentation, we focus on the magnetic acquisition campaigns, processing and 2D/3D interpretations by forward modelling and data inversion. Lastly, two items are discussed: 1) contribution of magnetic UAV surveys for geological mapping; and 2) implication of the results on the Chenaillet massif to discuss the contribution of magnetic mapping to the understanding of the TOC or ultra-slow spreading system.

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Using AIS Data for Navigational Risk Assessment in Restricted Waters

Advances in Environmental Engineering and Green Technologies - Marine Technology and Sustainable Development ◽

10.4018/978-1-4666-4317-8.ch015 ◽

2013 ◽

pp. 245-254

Author(s):

Adi Maimun ◽

Istaz F. Nursyirman ◽

Ang Yit Sian ◽

Rahimuddin Samad ◽

Sulaiman Oladokun

Keyword(s):

Risk Assessment ◽

Traffic Flow ◽

Assessment Method ◽

Collision Probability ◽

Traffic Density ◽

Automatic Identification ◽

High Concentration ◽

Marine Traffic ◽

Cross Traffic ◽

Strait Of Malacca

The Strait of Malacca is one of the most important shipping lanes in the world. It averages 150 ship passes a day and more than 50,000 ships annually. With a high concentration of vessels in a narrow path, multiple risk situations arise. Analyzing traffic density is made harder by cross traffic and an unknown traffic density at the Strait. In 2009, Universiti Teknologi Malaysia (UTM), through a collaboration with Kobe University, successfully installed an Automatic Identification System (AIS) receiver. Through the AIS receiver, data of ship movements in the Strait of Malacca and Singapore could be recorded. A program was established by UTM to retrieve the data for the purpose of marine traffic collision risk analysis. In this research, a risk assessment method using AIS data is proposed for restricted waters such as for the Strait of Malacca and Singapore. The Risk Assessment Methodology requires the estimation of collision probabilities. The collision probability of the proposed method considers the Traffic Density, directions of traffic flow (with respect to a subject vessel), and probability of navigational failure. An area in the Strait of Singapore between the latitudes of 1°13’N and 1°07’N and Longitudes of 103°4’E and 103°56’E was selected to illustrate the method. By analysing the AIS data of traffic flow, the probabilities of collision for the area were determined. The effect of vessel parameters of length and speed on the risks of collision are also shown.

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Application of Cellular Communications Models and Designs for Use in Disaster-Aftermath Related Scenarios

International Journal of Interdisciplinary Telecommunications and Networking ◽

10.4018/ijitn.2015070104 ◽

2015 ◽

Vol 7 (3) ◽

pp. 46-56

Author(s):

Stephen J. Curran

Keyword(s):

Unmanned Aerial Vehicles ◽

Ground Level ◽

Base Station ◽

Cellular Communications ◽

Fixed Position ◽

Above Ground Level ◽

High Altitude Platforms ◽

Major Disaster ◽

Future Strategy ◽

Low Altitude

This paper is a pilot study on the concept of an aerial base station as a future strategy for restoring cellular communications in the aftermath of a major disaster. The strategy being studied makes use of low altitude platforms (LAPs) or unmanned aerial vehicles (UAVs) that can hover or orbit in a relatively fixed position and can act as an aerial base station. Unlike High Altitude Platforms (HAP) operating in a layer of the atmosphere above any existing air traffic, the LAPs or UAVs will be able to operate a few hundred to some thousands of meters above ground level. This paper also describes the functionality of the components comprising the aerial base station.

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An Improved Ship Collision Risk Evaluation Method for Korea Maritime Safety Audit Considering Traffic Flow Characteristics

Journal of Marine Science and Engineering ◽

10.3390/jmse7120448 ◽

2019 ◽

Vol 7 (12) ◽

pp. 448 ◽

Cited By ~ 2

Author(s):

Yunja Yoo ◽

Tae-Goun Kim

Keyword(s):

Distribution Function ◽

Normal Distribution ◽

Traffic Flow ◽

Evaluation Method ◽

Collision Probability ◽

Normal Distribution Function ◽

Collision Risk ◽

Ship Traffic ◽

Ship Collision ◽

Best Fit

Ship collision accidents account for the majority of marine accidents. The collision risk can be even greater in ports where the traffic density is high and terrain conditions are difficult. The proximity assessment model of the Korea Maritime Safety Audit (KMSA), which is a tool for improving maritime traffic safety, employs a normal distribution of ship traffic to calculate the ship collision risk. However, ship traffic characteristics can differ according to the characteristics of the sea area and shipping route. Therefore, this study simulates collision probabilities by estimating the best-fit distribution function of ship traffic flow in Ulsan Port, which is the largest hazardous cargo vessel handling port in Korea. A comparison of collision probability simulation results using the best-fit function and the normal distribution function reveals a difference of approximately 1.5–2.4 times for each route. Moreover, the collision probability estimates are not accurate when the normal distribution function is uniformly applied without considering the characteristics of each route. These findings can be used to improve the KMSA evaluation method for ship collision risks, particularly in hazardous port areas.

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