Ground Facilities Research Articles

A novel bi-objective model for sustainable and efficient airport logistics management: A case study on Copenhagen airport

Due to the growing volume of air transportation and the scarcity of airport resources, aviation planners are paying more attention to the efficiency of airport resource management. Optimizing the assignment and scheduling of ground facilities plays an important role in reducing ground congestion, flight delays, and passenger dissatisfaction. To prevent any collisions among aircraft on the apron, taxi network, and runways, safety considerations should be strictly followed by traffic controllers. Minimizing taxi time is another matter of importance in airport logistics management that helps mitigate environmental concerns (e.g., fuel consumption, tire abrasion, and noise pollution). In this study, a bi-objective mixed-integer linear programming model is developed to optimize the ground resource scheduling problem, taking into account the challenges of gate assignment, taxi planning, and runway scheduling. The model is developed in a way that includes safety and sustainability considerations. The validation of the proposed model is investigated through several examples based on Copenhagen airport using the augmented ε-constraint method. Since the simultaneous scheduling of multiple resources is an NP-hard problem, two multi-objective metaheuristic algorithms are employed to deal with the large-scale problems. The performance of the algorithms is then compared in terms of coverage and convergence rates. Additionally, the results are discussed in detail to provide managerial implications for airport authorities.

Effect of multi-temperature models on heat transfer and electron behavior in hypersonic flows

In hypersonic computational fluid dynamics, the two-temperature (2-T) model is widely used to simulate thermochemical nonequilibrium. The 2-T model incorporates translational-rotational and electron-electronic-vibrational energies, assuming that the integrated energies have the equivalent temperature. In this study, multi-T models are constructed to accurately predict the effects on heat flux and free electrons due to the separation of energy modes under hypersonic environments. The three-temperature (3-T) model separates the electron-electronic energy from the electron-electronic-vibrational energy of the 2-T model. The 3-T model can accurately predict the distribution and temperature of free electrons by separating the energy of free electrons, which has different characteristics from heavy particles. The four-temperature model treats rotational energy as a nonequilibrium energy mode, distinct from translational-rotational energy. While the rotational temperature reaches equilibrium rapidly at low temperatures, at high-temperature regime rotational temperature shows a relaxation time similar to that of vibrational temperature, which cannot be ignored. To develop multi-T models, electron-vibrational relaxation and translational-rotational relaxation, which are omitted in the 2-T model, are considered. Various flight test and ground facility conditions are analyzed to verify the effects of electron and heat flux under circumstances that include shock, expansion, and shock wave boundary layer interaction. The results of the multi-T models show significant differences in electron temperature and distribution caused by electron-electronic nonequilibrium. Additionally, rotational nonequilibrium increases the shock standoff distance and alters the electron distribution at high altitudes. The heat flux difference across multi-T models is found to be negligible, except in the high degree of ionization condition.

Optimized Radio Frequency Footprint Identification Based on UAV Telemetry Radios.

With the widespread use of unmanned aerial vehicles (UAVs), the detection and identification of UAVs is a vital security issue for the safety of airspace and ground facilities in the no-fly zone. Telemetry radios are important wireless communication devices for UAVs, especially in UAVs beyond the visual line of sight (BVLOS) operating mode. This work focuses on the UAV identification approach using transient signals from UAV telemetry radios instead of the signals from UAV controllers that the former research work depended on. In our novel UAV Radio Frequency (RF) identification system framework based on telemetry radio signals, the EC-α algorithm is optimized to detect the starting point of the UAV transient signal and the detection accuracy at different signal-to-noise ratios (SNR) is evaluated. In the training stage, the Convolutional Neural Network (CNN) model is trained to extract features from raw I/Q data of the transient signals with different waveforms. Its architecture and hyperparameters are analyzed and optimized. In the identification stage, the extracted transient signals are clustered through the Self-Organizing Map (SOM) algorithm and the Clustering Signals Joint Identification (CSJI) algorithm is proposed to improve the accuracy of RF fingerprint identification. To evaluate the performance of our proposed approach, we design a testbed, including two UAVs as the flight platform, a Universal Software Radio Peripheral (USRP) as the receiver, and 20 telemetry radios with the same model as targets for identification. Indoor test results show that the optimized identification approach achieves an average accuracy of 92.3% at 30 dB. In comparison, the identification accuracy of SVM and KNN is 69.7% and 74.5%, respectively, at the same SNR condition. Extensive experiments are conducted outdoors to demonstrate the feasibility of this approach.

Current and future cosmological impact of microwave background temperature measurements

The redshift dependence of the cosmic microwave background temperature, T(z)=T0(1+z), is a key prediction of standard cosmology, but this relation is violated in many extensions thereof. Current astrophysical facilities can probe it in the redshift range 0≤z≤6.34. We extend recent work by Gelo et al. (2022) showing that for several classes of models (all of which aim to provide alternative mechanisms for the recent acceleration of the universe) the constraining power of these measurements is comparable to that of other background cosmology probes. Specifically, we discuss constraints on two classes of models not considered in the earlier work: a model with torsion and a recently proposed phenomenological dynamical dark energy model which can be thought of as a varying speed of light model. Moreover, for both these models and also for those in the earlier work, we discuss how current constraints may be improved by next-generation ground and space astrophysical facilities. Overall, we conclude that these measurements have a significant cosmological impact, mainly because they often constrain combinations of model parameters that are orthogonal, in the relevant parameter space, to those of other probes.

Import Substitution of UAVs and Economic Efficiency of Their Use for Patrolling Ground Facilities

Import Substitution of UAVs and Economic Efficiency of Their Use for Patrolling Ground Facilities

Ground Facility Error Analysis and GBAS Performance Evaluation Around Suvarnabhumi Airport, Thailand

Ground Facility Error Analysis and GBAS Performance Evaluation Around Suvarnabhumi Airport, Thailand

Multiwavelength View of Massive Binaries

The high luminosity of massive, early-type stars drives strong stellar winds through line scattering of the star’s continuum radiation. Their momenta contribute substantially to the dynamics and energetics of the ambient interstellar medium in galaxies. The detailed multiwavelength study of massive O-type and Wolf-Rayet binaries is essential to explore the hydrodynamics of the shocks formed in the stellar outflows and wind structure. Further, deep analysis of some of the interesting phenomena like particle acceleration and dust formation associated with hot stars’ winds provides a global view of stellar outflows. In this context, a few massive binaries have been explored using photometric and spectroscopic measurements in different wavebands. This paper highlights important insights gained from investigating massive binaries with several ground and space-based facilities.

The CELESTA CubeSat In-Flight Radiation Measurements and their Comparison with Ground Facilities Predictions

The CELESTA CubeSat In-Flight Radiation Measurements and their Comparison with Ground Facilities Predictions

MAINTENANCE MANAGEMENT ASSISTANCE FOR IMPROVING MONITORING OF LANDSIDE AREA FACILITIES AT I GUSTI NGURAH RAI AIRPORT BALI

I Gusti Ngurah Rai Airport on the island of Bali, an important gateway for tourism in Indonesia, faces challenges in managing landside facilities to support the growing number of passengers. In this study, we investigate the implementation of maintenance management assistance at I Gusti Ngurah Rai Airport in Bali and its impact on facility inspections in rural areas. The research method collects information through interviews, observation and analysis of relevant documents. The conclusion of this study is that maintenance management assistance is an effective way to overcome ground facility control problems at I Gusti Ngurah Rai Airport in Bali.The significance of this research lies in the importance of continuity of maintenance management assistance to maintain the quality of facilities and provide the best experience for all airport users.

Federated Deep Reinforcement Learning-Based Intelligent Dynamic Services in UAV-Assisted MEC

Unmanned Aerial Vehicles (UAVs)-assisted Multi-access Edge Computing (MEC) has emerged as a promising solution in B5G/6G networks. The high flexibility and seamless connectivity of UAVs make them well-suited for providing enhanced communications coverage and efficient computing support. Particularly in situations where ground facilities may be compromised or communication is unreliable. In this paper, we study joint dynamic service switching and resource allocation for multiple UAVs in MEC network. We consider the heterogeneity of tasks and UAVs and model the dynamic service process of UAVs as a sequential decision problem based on the Markovian decision process. To enable dynamic and intelligent UAV service, we first propose a centralized dynamic service algorithm DDBC based on deep reinforcement learning. However, given the training difficulties of the centralized algorithm, we propose a more promising distributed learning algorithm FLBF, which combines federated learning. We conduct extensive simulations to evaluate the effectiveness and advantages of the proposed algorithms. Our results show that both DDBC and FLBF can improve the model convergence speed by 50%, and reduce the system cost by 12.30% to 35.72% compared to comparative algorithms. Furthermore, simulations indicate that FLBF is well-suited for training models in UAV-assisted MEC networks.

Basic Electrophysical Characteristics of Natural Three-Phase Dispersed System “A Storm Cloud−Earth”

The results of engineering calculation of basic electrophysical characteristics of a three-phase dispersed system of the Earth troposphere “storm cloud-earth”, in the cloud of which a bearing gaseous air phase contains fine liquid water drops and small solid dielectric particles, are present-ed. The indicated characteristics are as follows: the total electric charge qΣ concentrated in a storm cloud of a given spherical volume V0 with finely dispersed charged inclusions in the form of water droplets of the radius rw and solid dielectric particles of the radius rd with the given cor-responding average volume densities Nw and Nd, respectively; the electric potential φr in the spherical volume V0 of a storm cloud with a specified outer radius R0; the electrical energy W0 accumulated in the volume V0 of a storm cloud with finely dispersed inclusions ; and the amplitude and temporal parameters of the pulse current iL(t) of the lightning in the plasma channel of a long air spark electrical discharge from the storm cloud to the ground. It is shown that at rw ≈ rd ≈ 5 μm, Nw ≈ 108 m-3, Nd ≈ 5106 m-3, R0 ≈ 895 m and the height of the center of a spherical storm cloud (with its volume of V0 ≈ 3109 м3) H0 ≈ 3000 m above the ground level, the following numerical values (in modulus) of the sought parameters of the system under consideration could be obtained: the accumulated cloud charge of qΣ ≈ 43.8 C; the electric potential on the outer cloud surface of φR ≈ 439 MV; the electric energy of W0 ≈ 9.61 GJ; the amplitude of the lightning current of ImL ≈ 218.5 KА corresponding to the time tmL ≈ 11.1 μs. The obtained results are in a good agreement with known experimental data related to the atmospheric electricity. They will contribute to a possibility of predicting thunderstorm conditions in the Earth troposphere with the minimal initial meteorological information, the further development of the nature of the atmospheric electricity, the physics of the linear lightning and solving the problem of the lightning protection of air and ground facilities and their personnel.

임차인이 지상물매수청구권을 행사한 경우, 석명의무와 동시이행항변권의 관계에 관한 연구

The supreme court case 94DA34265 (hereinafter referred to as ‘The Case’) says that in a lawsuit in which the lessor of land claims removal of ground facilities and delivery of the site against the lessee, if the lessee exercises the right to demand for the ground facilities purchase, the court has duty to elucidate whether the lessor is willing to demand delivery of the ground facilities at the same time as payment of the purchase price. (Hereinafter, elucidation above is referred to as ‘elucidation of simultaneous per- formance).
 At the basis of The Case, there appears to be an idea that if the lessor's claim changes to delivery of ground facilities, a judgment ordering simultaneous performance should be issued.
 However, according to majority opinion and precedent, for a judgment ordering simul- taneous performance to be issued, the lessee must file a plea of simultaneous performance. And the lessee's exercise of right to demand for purchase does not include a plea of simultaneous performance. Therefore, the idea that a judgment ordering simultaneous performance should be issued when the lessor's claim is changed to delivery of ground facilities is not valid. On the other hand, according to the minority theory that a ruling ordering simultaneous performance is possible even without a plea of simultaneous performance, the above idea is valid.
 According to the above majority opinion and precedent, elucidation of simultaneous performance is illegal as it exceeds the limits of the elucidation event. This is because the court indirectly informs the lessee of the existence of a plea of simultaneous performance by providing an elucidation of simultaneous performance to the lessor. On the other hand, according to the minority theory, the elucidation of simultaneous performance is not illegal because the outcome of the lawsuit is not affected even if the court informs the lessee of the existence of the plea of simultaneous performance.
 However, following the minority theory does not mean that elucidation of simultaneous performance is the court's duty. If the lessor requests delivery of ground facilities and the lessee's plea of simultaneous performance is acknowledged, the court may make a ruling upholding part of the claim. The court is not obligated to ensure that all claims are accepted through elucidation.
 In the end, The Case's position that elucidation of simultaneous performance is the court's duty is not valid, regardless of whether by majority or minority theory.

지역사회 토지이용자의 지상물매수청구권에 관한 연구

The Article 23 of the Constitution is being prescribed with saying that “The property rights of all citizens shall be guaranteed, but their contents and limits shall be determined by law, and that the exercise of property rights shall be allowed to be appropriate for public welfare.” The fundamental purport of this regulation is being interpreted to be what the acceptance, use or restriction of property rights due to the public needs is exceptionally permitted only if the requirements prescribed by the Constitution are met while giving a guarantee to the free use, profit, and disposal of all citizens' property rights under the basic principle dubbed the guarantee of the private property system.
 By the way, as the mandatory provision with saying what is available for asking a landowner to buy at a certain price without removing or collecting the ground objects by land users given the expiration date after the use or profit in accordance with the agreement of the parties concerning the land of another person, it is being regarded as the formative right. However, in terms of applying and interpreting the Article 283 of the Civil Code by the person with superficies pertinent to the Right to Demand for the Ground Facilities Purchase, it is considered to be appropriate to see it as a case of corresponding to being below the minimum duration of the superficies in the Article 280 of the Civil Code according to the term of the contract of the parties.

Experimental and numerical Investigation of entrapped air presence and expulsions in irregular pipelines on hydraulic transients

In the present study, the transient event of rapid opening of upstream valve in undulated water pipeline with entrapped air pockets was investigated both experimentally and numerically. Pressure peaks and oscillation patterns were traced with the variation of air pocket length, blocking column length and water filling column. A transient two-dimensional CFD simulation model was introduced and validated by laboratory experiments. The proposed CFD model was conducted using ANSYS fluent based on Reynolds-averaged Navier–Stokes (RANS) equations and the volume of fluid (VOF) method. A user-defined functions (UDF) for both water compressibility effect and opening valve estimated pattern were adopted to verify the experimental results. For further understanding of transient response air expulsion through air vents of various orifices diameters were experimentally investigated. Image processing technique by using photoshop were utilized to clarify Stages of air expulsions, air water interaction and orifice flow regime. The obtained results showed that pressure peaks and oscillations depend strongly on orifice size where small orifice caused an intermitted flow choked by water column in contrast to large orifice where water hammer was dominated. An experimental facility was constructed at Alexandria university hydraulics laboratory to fulfil the research objectives. Air presence challenges in hydraulic systems are extensively applied for water and fuel supply lines, firefighting, and drainage systems in airports ground facilities.

Prediction of ground subsidence by shield tunneling using ensemble learning

This study addresses a significant issue related to shield construction, namely the impact of shield construction parameters on ground subsidence. Shield tunnels, owing to their concealed construction, often lead to ground subsidence, causing severe disruptions to ground facilities, potential collapse, and consequent casualties and property loss. Most calculation methods for ground subsidence have a delay, making it difficult to predict ground subsidence in advance based on construction parameters. Therefore, this study collates over 1500 cases of shield construction in China and summarises the impact mechanisms of shield construction on ground subsidence through a detailed study of natural factors, engineering geology, types of structures, and types of construction parameters. Based on the influence law of the data, this study establishes three intelligent prediction methods to forecast ground subsidence. To select the hyperparameters in the models more effectively, a Bayesian optimisation algorithm was utilised. Through a comparative analysis of the models, a subsidence prediction method that is more in line with the construction characteristics and exhibits high accuracy was determined. The findings of this study serve as a valuable resource for predicting ground subsidence resulting from shield construction, enabling timely adjustments to construction parameters and the implementation of preventive measures to mitigate excessive subsidence.

Preface

The 15th International Symposium on Materials in the Space Environment (ISMSE) and 13th International Conference on Protection of Materials and Structures from the Space Environment (ICPMSE) took place 18-23 September 2022 in a special venue, the Naturalis Biodiversity Center in the beautiful city of Leiden (the Netherlands). This joint conference was attended by about 210 participants from 25 different countries worldwide.We are now happy to present to you the final version of the conference proceedings. This unique collection includes 42 original scientific papers in a variety of fields, including:• Contamination modelling, applications and monitoring,• Low / Very low Earth orbit (LEO/VLEO),• Lunar environment and dust,• Clean Space and sustainability,• Flight experiments,• Radiation and synergistic effects,• Innovative materials and processes,• Ground facilities and testing,• Long-term storage.The papers reflect well the topics discussed during the conference.To maintain the high quality of the papers, we used a single-blind peer-review process, established within the framework of the Morresier platform provided by IOP. Moreover, all papers are now assigned DOIs and published open access online by IOP.The papers resulted from at least 4 years of work since the last ISMSE conference. Some authors are contributing to several papers as they actively work in several research subgroups and supervise multiple student projects. In each case all authors have contributed to all mandatory aspects: substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work; and drafting the work or revising it critically for important intellectual content; and final approval of the version to be published; agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.We hope you find the proceedings informative and we look forward to more exciting high-quality research publications in the future as part of the forthcoming ISMSE-16/ICPMSE-14 event.ISMSE Proceedings Editorial Board:Malgorzata Holynska (Chair, ESA/ESTEC)Adrian Tighe (ESA/ESTEC)Elisabeth Laurent (CNES)Jacob Kleiman (ITL INC)Sophie Duzellier (ONERA)Timothy Minton (University of Colorado Boulder)

Regulation of environmental safety at the stages construction of main pipelines

Pipeline transport plays a special role in the unified transport system of the Russian Federation. Today, almost the entire volume of gas is delivered through the main pipelines. The technology of transportation of natural gas, oil, condensate and their byproducts, constructive solutions of the linear part and ground facilities influence the natural environment. Therefore, the issue of compliance with environmental protection rules in constructing pipeline transport facilities is relevant. It is of special significance due to the construction of new transport routes in the Asian region. The article analyzes legal documents on the stages of construction of linearly extended objects such as oil and gas pipelines. It was revealed that the compliance with the construction requirements reduces the damage to nature, but does not eliminate it. It was concluded that the production improvement is the most rational method of reducing the negative impact of construction on natural ecosystems. The analysis made it possible to provide recommendations for amending the environmental protection legislation.

Evaluation of the Trade-Off between Ground Delays and Intersecting Departures under Various Pilot Acceptance Rate Scenarios

The increasing demand for air traffic at airports necessitates the efficient utilization of ground facilities such as runways and taxiways. Intersecting departures, in which one or more aircraft take off from intersecting points on the runway, is a commonly used approach to increase runway capacity and reduce ground delays and taxi times, as well as noise and air pollution. However, the procedure carries potential risks such as runway incursion and excursion. This creates a trade-off between minimizing the number of intersecting departures and minimizing ground delays. In practice, the decision to perform an intersecting departure is ultimately up to the pilot, resulting in uncertainty in the acceptance rate of these types of takeoffs. In this study, a departure sequencing model was developed for a single-runway airport that considers intersecting departures and various pilot acceptance rate scenarios. The primary objective of the model is to minimize total ground delay, including taxi delays, runway holds, and conflict holds. The secondary objective is to minimize the number of intersecting departures by directing the most operationally critical aircraft to the intersection takeoff. The epsilon constraint method—a multi-objective scalarization method—was used to reveal the trade-offs between the objective functions. The results of the model were compared with a traditional scenario that only allows take offs from the beginning of the runway. As a result, average delay savings ranged from 17.1% to 31.5% in various acceptance rate scenarios, as well as average taxi time savings ranging from 4.9% to 8.4% compared with the traditional scenario.

(In)security alert! Who is guarding the airport?

Security at airports represents a major risk exposure. Poorly paid and underappreciated staff are tasked with controlling critical access points to ground and airside facilities. This paper describes a review of security services at a major North American airport, based on interviews conducted with management and personnel of a contracted service provider. It also evaluates service quality, contract compliance and the business processes involved in the delivery of those services. The review identified significant problems with staff turnover, training and performance; all factors that could lead to compromised security. It also examined the value received for money spent on delivering security services, considering their: (i) economy; (ii) efficiency and (iii) effectiveness. While this review was confined to a single airport, it is expected that the methodology adopted, as well as the problems noted, will apply to other aviation facilities.

Detection of Anomalies in Natural Complicated Data Structures Based on a Hybrid Approach

A hybrid approach is proposed to detect anomalies in natural complicated data structures with high noise levels. The approach includes the application of an autoencoder neural network and singular spectrum analysis (SSA) with an adaptive anomaly detection algorithm (AADA) developed by the authors. The autoencoder is the quintessence of the representation learning algorithm, and it projects (selects) data features. Here, under-complete autoencoders are used. They are a product of the development of the principal component method and allow one to approximate complex nonlinear dependencies. Singular spectrum analysis decomposes data through the singular decomposition of matrix trajectories and makes it possible to detect the data structure in the noise. The AADA is based on the combination of wavelet transforms with threshold functions. Combinations of different constructions of wavelet transformation with threshold functions are widely applied to tasks relating to complex data processing. However, when the noise level is high and there is no complete knowledge of a useful signal, anomaly detection is not a trivial problem and requires a complex approach. This paper considers the use of adaptive threshold functions, the parameters of which are estimated on a probabilistic basis. Adaptive thresholds and a moving time window are introduced. The efficiency of the proposed method in detecting anomalies in neutron monitor data is illustrated. Neutron monitor data record cosmic ray intensities. We used neutron monitor data from ground stations. Anomalies in cosmic rays can create serious radiation hazards for people as well as for space and ground facilities. Thus, the diagnostics of anomalies in cosmic ray parameters is quite topical, and research is being carried out by teams from different countries. A comparison of the results for the autoencoder + AADA and SSA + AADA methods showed the higher efficiency of the autoencoder + AADA method. A more flexible NN apparatus provides better detection of short-period anomalies that have complicated structures. However, the combination of SSA and the AADA is efficient in the detection of long-term anomalies in cosmic rays that occur during strong magnetic storms. Thus, cosmic ray data analysis requires a more complex approach, including the use of the autoencoder and SSA with the AADA.