Solar flares are one of the severest solar activities that have important effects on near-Earth space. Previous studies have shown that flight arrival delays increase as a result of solar flares, but ...the intrinsic mechanism behind this relationship is still unknown. In this study, we conducted a comprehensive analysis of flight departure delays during 57 solar X-ray events by using a huge amount of flight data (~ 5 × 10
records) gathered over a 5-year period. It is found that the average flight departure delay time during solar X-ray events increased by 20.68% (7.67 min) compared to quiet periods. Our analysis also revealed apparent time and latitude dependencies, with flight delays being more serious on the dayside than on the nightside and longer (shorter) delays tending to occur in lower (higher) latitude airports during solar X-ray events. Furthermore, our results suggest that the intensity of solar flares (soft X-ray flux) and the Solar Zenith Angle directly modulate flight departure delay time and delay rate. These results indicate that communication interferences caused by solar flares directly affect flight departure delays. This work expands our conventional understanding of the impacts of solar flares on human society and provides new insights for preventing or coping with flight delays.
•Airlines subject to HSR competition reduce the number of seats offered in the route.•Frequencies might not be reduced as much by airlines, to keep competing with HSR.•Results vary across countries ...depending on HSR network design and length.•HSR stations in hub airports can feed air demand, thus partially compensating effects from competition.
New high-speed rail (HSR) lines may have an enormous influence on the provision of air services. The attention has been devoted to competition between both transportation modes but in some cases HSR services may also have an intermodal complementary role with air transportation. By taking a supply oriented empirical analysis, we study the impact of HSR on air service frequencies and seats offered by airlines in large European countries. We emphasize the distinction between routes with and without a hub airport as an endpoint and we also examine the influence of the location of the HSR station. We generally find direct competition between HSR and airlines, but we also provide some evidence that HSR can provide feeding services to long haul air services in hub airports, particularly in hub airports with HRS stations.
* We see no chance right now to implement curved approaches with GBAS. * RNP is the better alternative for us. * The Ground Coordinator Concept seems to be a good opportunity to get more out of the ...whole system. * Drones/UAV and their functions will have an impact on airport operations - a safe integration into the system is paramount. Isolated applications hamper further improvements. We have to work together to achieve future goals and to contribute to a smoother air traffic system.
An appropriate time series model for predicting passenger data of Djalaluddin Gorontalo Airport, the interval between 2003 - 2017 with the multiplicative of Holt's-Winters' exponential smoothing as ...Y^t+p=(Lt+pTt)St−12+p, where for time t, the original exponential smoothing data, Lt=0.2YtSt−12+0.8(Lt−1+Tt−1), smoothing trend patterns Tt = 0.2(Lt − Lt−1) + 0.8Tt−1 and smoothing seasonal patterns, St=0.2YtLt+0.8St−12, so the smoothing parameter used are α = β = γ = 0.2. After several treatments, the mean square deviation (MSD) is 3287241 for arrival passenger data and MSD is 2490279 for passenger departure data with a seasonal length of 12 by do not event-based. The next, the MSD is 1334585 for arrival passenger data and MSD is 1433867 for passenger departure data with a seasonal length of 12 by Eid al-Fitr event-based, the MSD is 1259600 for arrival passenger data and MSD is 1252548 for passenger departure data with a seasonal length of 12 by Eid al-Adha event-based.
The efficiency and effectiveness of airport security can be improved through fast and high-fidelity detection of concealed threat objects. If detected objects can be accurately characterized, the ...number of false alarms will be reduced, whereas terrorist threats can be more quickly noticed and apprehended. This article aims to accurately characterize the physical properties of weak dielectric objects (such as explosive threats) covering a conductive plane (such as the human body) using a single-frequency millimeter-wave (mm-wave) radar system with a Fresnel aperture. While the conventional synthetic aperture radar (SAR) method requires data over a broad bandwidth, our proposed method works even at a single frequency and is particularly suitable for focused-beam CW mm-wave sensing systems. This method is validated with experimental data.
•A new phase technique for detecting forgeries in IMEI and air tickets.•It derives phase spectrum using DCT to find suspicious regions.•We compute phase statistics to study the effect introduced by ...forgery.
New tools have been developing with the intention of having more flexibility and greater user-friendliness for editing the images and documents in digital technologies, but, unfortunately, they are also being used for manipulating and tampering information. Examples of such crimes include creating forged International Mobile Equipment Identity (IMEI) numbers which are embedded on mobile packages and inside smart mobile cases for illicit activities. Another example of such crimes is altering the name or date on air tickets for breaching security at the airport. This paper presents a new expert system for detecting forged IMEI numbers as well as altered air ticket images. The proposed method derives the phase spectrum using the Discrete Cosine Transform (DCT) to highlight the suspicious regions; it is unlike the phase spectrum from a Fourier transform, which is ineffective due to power spectrum noise. From the phase spectrum, our method extracts phase statistics to study the effect of distortions introduced by forgery operations. This results in feature vectors, which are fed to a Support Vector Machine (SVM) classifier for detection of forged IMEI numbers and air ticket images. Experimental results on our dataset of forged IMEI numbers (which is created by us for this work), on altered air tickets, on benchmark datasets of video caption text (which is tampered text), and on altered receipts of the ICPR 2018 FDC dataset, show that the proposed method is robust across different datasets. Furthermore, comparative studies of the proposed method with the existing methods on the same datasets show that the proposed method outperforms the existing methods. The dataset created will be available freely on request to the authors.
•Improvements in airport accessibility.•Users and non-users of airport services have differing preferences.•Frequency for public transport is pivotal for airport users.•Non-users are more sensitive ...to travel cost.•Improvements in bus services would penalise the direct train more than car.
In this paper, we analyse residents' decisions regarding airport access mode in Apulia, a relatively peripheral multi-airport region in Italy. Both revealed and stated preferences data are used to estimate probabilistic demand models. The results are employed to calculate the relevant elasticities, separately for airport users and non-users, with respect to dedicated existing and planned/potential public transport services. We measure the effectiveness of specific policies/actions aimed at generating a shift from private modes (car and taxi) towards public transport, rationalising mobility towards the existing airports. Accessibility is one of the key factors in airports' provision, and an efficient public transport system might represent both an alternative to opening “local” – often costly and inefficient – airports in the same catchment area and a means to exploit economies of scale aggregating demand for existing airports.
The US government imposed two travel restriction policies to prevent the spread of the COVID-19 but may have funneled asymptomatic air travelers to selected major airports and transportation hubs. ...Using the most recent JHU COVID-19 database, American Community Survey, Airport and Amtrak data form Bureau of Transportation Statistics from 3132 US counties we ran negative binomial regressions and Cox regression models to explore the associations between COVID-19 cases and death rates and proximity to airports, train stations, and public transportation. Counties within 25 miles of an airport had 1.392 times the rate of COVID-19 cases and 1.545 times the rate of COVID-19 deaths in comparison to counties that are more than 50 miles from an airport. More effective policies to detect and isolate infected travelers are needed. Policymakers and officials in transportation and public health should collaborate to promulgate policies and procedures to protect travelers and transportation workers from COVID-19.
•Number of COVID-19 cases and deaths are positively related to proximity to and passenger volume of the nearest airport.•Length of time until first COVID-19 cases and deaths are positively related to proximity to nearest international airport and passenger volume.•Numbers of deaths and cases were positively correlated with the number of airports, number of train stations, and the percentage of adults using public transportation.
Steadily rising mean and extreme temperatures as a result of climate change will likely impact the air transportation system over the coming decades. As air temperatures rise at constant pressure, ...air density declines, resulting in less lift generation by an aircraft wing at a given airspeed and potentially imposing a weight restriction on departing aircraft. This study presents a general model to project future weight restrictions across a fleet of aircraft with different takeoff weights operating at a variety of airports. We construct performance models for five common commercial aircraft and 19 major airports around the world and use projections of daily temperatures from the CMIP5 model suite under the RCP 4.5 and RCP 8.5 emissions scenarios to calculate required hourly weight restriction. We find that on average, 10 - 30% of annual flights departing at the time of daily maximum temperature may require some weight restriction below their maximum takeoff weights, with mean restrictions ranging from 0.5 to 4% of total aircraft payload and fuel capacity by mid- to late century. Both mid-sized and large aircraft are affected, and airports with short runways and high temperatures, or those at high elevations, will see the largest impacts. Our results suggest that weight restriction may impose a non-trivial cost on airlines and impact aviation operations around the world and that adaptation may be required in aircraft design, airline schedules, and/or runway lengths.
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