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This paper analyses over 10,000 quality‐controlled pilot reports of low‐level wind shear ('wind shear') at the Hong Kong International Airport (HKIA; ICAO code: VHHH) between 2001 and 2019. HKIA is well known for its susceptibility to wind shear, which is a potential hazard for aircraft during landing and take‐off. Wind shear at HKIA exhibits strong seasonality with double peaks in the middle of the spring and summer months. There is a strong diurnal cycle in report numbers, peaking towards the afternoon, as modulated by air traffic at HKIA. On average, there are 115 days per year with wind shear reported, with possible power law distribution in the number of days with different number of reports. By comparing the background wind distribution during those minutes with pilot reports against the climatological distribution, wind shear is observed to be, on average, favoured under higher wind speeds (≥6 m s−1) and reduced under lower speeds with shifted frequency peak and heavier tail, although statistical behaviour can differ significantly across individual runway corridors. Preferred background wind directions for wind shear occurrence highlight the role of terrain influence upstream of HKIA. While positive shear (65.6%) is more often reported than negative shear (34.4%), both types of wind shear events appear to follow an exponential distribution in shear magnitude, with similar rates of decay. This is by far the largest statistical study of low‐level wind shear at an airport. Results can serve as an important local reference in addition to being a useful example for airports around the world. [ABSTRACT FROM AUTHOR]

The paper investigates the multiple public-private exchanges and cooperation involved in the installation and development of CCTV surveillance at Geneva International Airport. Emphasis is placed on the interacting forms of authority and expertise of five parties: the user(s), owner and supplier of the camera system, as well as the technical managers of the airport and the Swiss regulatory bodies in airport security. While placing the issues of airport surveillance in the particular context of a specific range of projects and transformations relating to the developments of CCTV at Geneva Airport, the paper not only provides important insights into the micro-politics of surveillance at Geneva Airport, but aims to re-institute these as part of a broader ‘problematic’: the mediating role of expertise and the growing functional fragmentation of authority in contemporary security governance. On this basis, the paper also exemplifies the growing mutual interdependences between security and business interests in the ever growing ‘surveillant assemblage’ in contemporary security governance. [ABSTRACT FROM AUTHOR]

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In today's highly competitive air transportation environment, the quality of airport service is an important issue. In this paper, we present a fuzzy multi-criteria decision-making (MCDM) method for the evaluation of the quality of airport service. The data are collected from the passengers who depart from two international airports in Taiwan. The fuzzy MCDM model is defuzzied using the inverse function arithmetic representation method. The results show that the average quality of the Taoyuan International Airport service is better than that of the Kaohsiung International Airport service. This paper also analyses the quality of airport service using the fuzzy expert system to improve the performance of airport service. The analysis results show that the Kaohsiung International Airport and the Taoyuan International Airports' improvement efforts should be concentrated on seven and five specific service items, respectively. The findings of this paper are to help the decision-makers and the managers of airports improve the quality of airport service. [ABSTRACT FROM AUTHOR]

Organisational restructuring towards vertical disintegration and the accompanying rise of service delivery network (SDN) calls for closer attention, studying whether and how work and employment are strategically managed across organisational boundaries. In this paper, we adopt a "strategy‐as‐practice" approach to explain the emergence of an Human Resource Management (HRM) strategy which is geared towards managing work across organisational boundaries. Based on a comparison of two German major hub airports, we find that differences in network‐oriented HRM strategising in areas such as recruiting, remuneration and training result from micro‐political game playing. In this piecemeal process, management as well as external and internal stakeholders such as workers' representatives, and local and federal politicians participate by using their inter‐organisational relationships and institutionalised power resources to shape a network‐oriented HRM practice. With these findings, we contribute not only to HRM research from a strategy‐as‐practice perspective that is sensitive to institutions, but also to research on inter‐organisational collaboration that has neglected issues of HRM so far, by and large. [ABSTRACT FROM AUTHOR]

Small-scale, fast-evolving airflow disturbances, possibly due to upstream building clusters, are known to affect aircraft landing at corridor 25RA of Hong Kong International Airport (HKIA), China, under southerly or southwesterly winds. The paper presents a new algorithm, based on the concept of coherent integrated differential velocity (CIDV), for the automatic alerting of such hectometric (scale of hundreds of metres) turbulence features using short-range LIDAR (SRL) scans at 30 m radial resolution and an observation frequency of around every 20 s by Hong Kong Observatory (HKO). The CIDV identifies the cumulative effect of coherent patches of radial velocity changes occurring along the landing flight path by comparing two consecutive subminute SRL scans. Verification was conducted between June and September 2017 against a selection of relevant pilot reports, with a positive skill level observed over the whole range of the CIDV thresholds considered. When simulating a realistic setting where the SRL would issue alerts in conjunction with HKO's operational Windshear and Turbulence Warning System (WTWS), the CIDV algorithm would bring a gain in hit rate between 5% and 25%, with a corresponding increase in alert duration between 0.4% and 20%. The chosen CIDV threshold of 0.4 m·s-1 nautical mile (nm) can be physically interpreted as an average radial velocity change of 4.0 m·s-1 sustained over a distance of < 200 m (or between 2 and 3 s of flight), which agrees with reported values of crosswind changes considered significant for a landing aircraft and also pilots' perception of the characteristics of such events. [ABSTRACT FROM AUTHOR]

Nowadays, airports' interest in solar photovoltaics (PVs) is increasing. It is a way to lower the burden of energy costs and to show environmental stewardship. This paper aims to study the application of PVs in the airport environment. Solar projects in airport areas across the world were studied to find the techno‐economic and environmental aspects of airport‐based solar PV application. The favorable factors for solar PV are observed to be effective land utilization, low height profile, versatility, flexibility, and mature silicon PV technology. The major considerations for airport‐based solar PV applications were glare occurrence, radar interference, and penetration into airspace. Airport's weather and soil conditions, selection of PV technology, glare impact, site selection, and grid interconnection issues were the technical challenges. It was observed that economic factors such as reduced energy cost, life cycle cost, and sustainability grants and incentives make solar projects in airports attractive. Carbon mitigation and achievement of sustainability goals through solar PV installation emphasized the environmental stewardship of airports. From case studies, it was understood that prior planning, glare assessment, and careful implementation are essential for the success of airport‐based solar PV farms. Airport‐based solar PV has immense scope in the near future. [ABSTRACT FROM AUTHOR]

This paper estimates the effects of airport infrastructure on employment and the distribution of the labor force in US metropolitan areas. The analysis is based on models for the air network and for its effects on employment, which are estimated using US data. Air traffic is found to have a positive effect on the population of the local area, with an elasticity of 0.010, so airport improvements induce a reallocation of workers between regions. Air traffic is also found to have a positive effect on employment in the local area with an elasticity of 0.036 and a weakly positive effect on the employment rate in other places within 400 miles. Simulations suggest that for each job created in the local area by an airport expansion, two and a half jobs are created elsewhere in the United States due to the changes in the air network and the distribution of employment. Expanding the average airport adds one job in the United States for roughly each $78,000 invested. The results further suggest that the US air network is less centralized than would be optimal. [ABSTRACT FROM AUTHOR]

In order to explore the application of multi-source data from different observational systems (includingmeteorological stations, radar, and airport observational reports) and high-resolution numerical model results in the analysis of severe convective weather affecting airports, a local severe convective weather event that affected Beijing Capital International Airport (ZBAA) on 26 June 2018 was studied in this work. Although there was no significant triggering of synoptic systems, the process produced a violent thunderstorm with strong wind gusts, poor prevailing visibility, and hail in just a 30-min period, resulting in severe impacts on the airport operations. In addition to the routine analysis of weather using observations from meteorological stations and radar, high spatial and temporal resolution data from instruments at the airport were used to reveal the fine-scale characteristics of the development and evolution of various associated meteorological parameters, which demonstrably served as a useful auxiliary dataset for the analysis of this event. Furthermore, the reliability of the high-resolution numerical (Weather Research and Forecasting) model simulation was evaluated by using these 1-min-scale airport observations. Based on what was judged to be a reliable simulation of the meteorological variables by the model, the trigger and strengthening mechanisms of the storm formed in this region of complex topography, as well as the interaction with another cell, were explored. The model results suggested that convections were initially triggered by the interaction of southerly flow from the plain and northwesterly flow from the mountains, in conjunction with the effect of orographic uplift. The outflow of the cold pool from the former cell prevented the later cell (affecting ZBAA) from moving east. Due to the strong vertical wind shear in the lower levels, the echo tilted to a certain extent and formed an inner secondary circulation, contributing to themaintenance and strengthening for the storm. [ABSTRACT FROM AUTHOR]

GM_PHD (Gaussian mixture of probability hypothesis density) cannot completely track multiple targets, such as the flying birds in the complex low-altitude airspace near the airport, due to the lack of the steps of birth detection, track extraction and death detection. A new algorithm is proposed to solve this problem, which mainly contributes to the following three aspects. First, the k-nearest neighbour algorithm is used to detect the birth of bird targets from measurements which is necessary to construct the birth intensity function. Second, the clustering algorithm is introduced into the probability hypothesis density filter framework to extract the bird targets' tracks from the filtering results. Third, an algorithm is added to detect the death of bird targets for better tracking. The Gaussian mixture implementation of the algorithm denoted as BT_GM_PHD (Bird Tracking GM_PHD) is presented. The test results on simulation and ground-truth data show that the proposed BT_GM_PHD algorithm can effectively track the multiple flying bird targets in the complex low-altitude airspace near the airport, outperforming the GM_PHD filter. [ABSTRACT FROM AUTHOR]

With the aim of developing a forecasting system for the prediction of adverse meteorological conditions in the vicinity of complex terrain for aircraft landing at Hong Kong International Airport, the linearized, quasi‐empirical FLOWSTAR model has been configured to represent a series of eight landing events (2015–2017); half of these events reported significant wind shear and, for two, the landing attempt was aborted. Meteorological data used as input to the model have been derived from Hong Kong Observatory radiosonde measurements; these are the most reliable available despite being recorded at a location distant from the airport and at one or more hours before or after landing events. In general, the model predicts stronger wind shear for cases where adverse conditions have been reported. Analysis of the magnitude of wind shear generated as a result of wind veering and backing helps to quantify the importance of nonlinear flow features such as trapped lee waves. The model is able to represent strong downslope flows and recirculating flow regions (rotors) generated by the mountainous region located upwind of the airport. Comparisons of model predictions against LIDAR traces indicate that the model replicates wind shear for 50% of cases where it was recorded, although the location and magnitude of the wind shear usually differs between the modelled and measured datasets; the lack of agreement is likely to be because the input meteorological conditions are not wholly representative of the upstream conditions and the LIDAR trace does not exactly coincide with the aircraft trajectory. When airports are located in hilly terrain, near‐ground flow features such as wind shear and turbulence periodically cause disruption to aircraft movements. The FLOWSTAR model has been configured to represent favourable and unfavourable landings at Hong Kong International Airport; the model predicts high wind shear at some locations along the flight path (black dotted line). Quantitative analyses of wind shear generated as a result of wind veering and backing demonstrate the importance of flow features such as trapped lee waves. [ABSTRACT FROM AUTHOR]

Abstract: This study provides the first empirical assessment of the impact airline delays have on urban employment. While previous works have suggested that road congestion can slow down regional development, the influence of air traffic delays on metro‐level jobs has not been examined comprehensively. The present study uses a nine‐year panel of quarterly data, which covers passenger airline traffic and delays at airports across urban areas in the United States. The panel also includes data on total and industry‐specific employment at the metropolitan‐area level. Our empirical estimates of the impact of air traffic on total employment are comparable to previously reported measures in the literature. However, we find that service‐sector employment is less sensitive to air traffic than other studies suggested. We provide new evidence confirming that delays have a negative effect on employment, a finding that is robust to various specifications of our empirical model. Our results indicate that a 10 percent increase in the number of delayed flights leads to up to a 0.15 percent decrease in total and service‐sector employment, a 0.47 percent decline in leisure and hospitality employment, and a 0.7 percent reduction in the employment level of goods‐producing jobs. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel system for real-time prediction of wind speed and direction in a critical region of complex terrain is developed by combining measurements and analytically based fast computation of the flow field. The new system is applied to the aircraft approach flight paths of Hong Kong International Airport ( HKIA), where orographically generated turbulence downwind of a mountain ridge in high-wind conditions causes disruptions to aircraft movements regularly. By using wind profiler and radiosonde measurements to drive the analytically based ' FLOWSTAR' model, good agreement is demonstrated between modelled and observed wind flow data from a network of ground-based monitors and LIDAR scans in the vicinity of the airport for a historical wind event. The methodology forms the basis of a system that can be used to forecast extreme wind events. [ABSTRACT FROM AUTHOR]

Collisions between birds and aircraft cause billions of dollars of damages annually to civil, commercial, and military aviation. Yet technology to reduce bird strike is not generally effective, especially over longer time periods. Previous information from our lab indicated that filling an area with acoustic noise, which masks important communication channels for birds, can displace European Starlings (Sturnus vulgaris) from food sources. Here we deployed a spatially controlled noise (termed a "sonic net"), designed to overlap with the frequency range of bird vocalizations, at an airfield. By conducting point counts, we monitored the presence of birds for four weeks before deployment of our sonic net, and for four weeks during deployment. We found an 82% reduction in bird presence in the sonic net area compared with change in the reference areas. This effect was as strong in the fourth week of exposure as in the first week. We also calculated the potential costs avoided resulting from this exclusion. We propose that spatially controlled acoustic manipulations that mask auditory communication for birds may be an effective long term and fairly benign way of excluding problem birds from areas of socioeconomic importance, such as airfields, agricultural sites, and commercial properties. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the fatal injuries on birds due to the collisions from aircrafts to determine their anti-predator behaviours. It mentions that necropsies are conducted on 92 birds to determine the injuries sustained by examining the bone and muscle group. It reveals that the ventral and posterior injuries indicate the evasive behaviour and the behavioural lateralization of the birds against the approaching aircraft.