bluuebunny/crossref_metadata_2025 huggingface dataset:
Electromagnetically induced grating realization in phaseonium
Authors: Badshah Fazal , Abbas Muqaddar , Asghar Sobia , Xie Jin , Rahmatullah
Published: June 2023

We propose a method to implement electromagnetically induced grating in a phaseonium medium that has been coherently generated via atomic mechanisms. Phaseonium atoms have a Λ-type structure and three distinct energy levels; such atoms are originally generated in a coherent superposition of two lower levels. The phaseonium system is comprised of three-level atoms with a Λ-type configuration, which are initially prepared in a coherent superposition of two lower levels. To accomplish this spatial modulation based on the susceptibility of phaseonium medium, a standing-wave field is used. By looking at how an optical field diffracts at different relative phases, we find that the zeroth and first order diffraction intensities increase as the relative phase changes. We also investigate the impact of the Rabi frequency of the field on diffraction intensity and notice that an increasing strength of the Rabi frequency leads to amplification in the intensity of both central zeroth order and first-order diffraction. Furthermore, it has been observed that a significant rise in diffraction intensity occurs at longer interaction lengths between external fields and the atomic medium.
Crysformer: An attention-based graph neural network for properties prediction of crystals
Authors: Wang 王 Tian 田 , Chen 陈 Jiahui 家辉 , Teng 滕 Jing 婧 , Shi 史 Jingang 金钢 , Zeng 曾 Xinhua 新华 , Snoussi Hichem
Published: June 2023

We present a novel approach for the prediction of crystal material properties that is distinct from the computationally complex and expensive density functional theory (DFT)-based calculations. Instead, we utilize an attention-based graph neural network that yields high-accuracy predictions. Our approach employs two attention mechanisms that allow for message passing on the crystal graphs, which in turn enable the model to selectively attend to pertinent atoms and their local environments, thereby improving performance. We conduct comprehensive experiments to validate our approach, which demonstrates that our method surpasses existing methods in terms of predictive accuracy. Our results suggest that deep learning, particularly attention-based networks, holds significant promise for predicting crystal material properties, with implications for material discovery and the refined intelligent systems.
Aerodynamic modelling of a tilt-wing transition corridor
Authors: Kulhánek Robert , Vrchota Petr , Hospodář Pavel
Published: June 2023

With the recent rapid evolution of the UAM class concepts in past years, the re-emerged interest in VTOL concepts and their aerodynamics arises. The tilt-wing is one of the possible solutions for such a vehicle. Recent decades of tilt-wing aerodynamic research point to the importance of the understanding transition regime from cruise to hover. Especially the wing stall phenomena which affect descent capabilities and control during the landing phase. Understanding such a regime is crucial for optimal wing design. This paper presents several approaches to the modelling of aerodynamic forces during the critical phase of transition. Computations are aimed particularly to the edge of the flight envelope. The low to high fidelity methods are employed and compared with the results of low-speed wind tunnel testing. The results from high fidelity methods match well with experimental results but the proposed simple analytical model fails in prediction of the transition corridor in the most critical regimes.
Parametric investigation of the aerodynamic and acoustic performance of a low-boom supersonic airliner
Authors: Bliamis C , Papadopoulos P , Yakinthos K
Published: June 2023

In the present work, a parametric design study in the conceptual design phase of a low-boom supersonic airliner (LBSSA) is presented. The low-boom constraint is of great importance to the near future supersonic airliners, in order for them to be certified for overland operation, but is also usually associated with a penalty in their aerodynamic performance (e.g. increased drag) and subsequently a higher fuel consumption. In this work, a dedicated low-fidelity design tool for the conceptual and early preliminary design of a LBSSA is developed which includes both Class-I and Class-II weight calculations. The design tool is also capable of predicting the aircraft’s aerodynamic performance in both the subsonic and supersonic cruise segments of its mission. The aerodynamic behavior of the LBSSA is then compared against the results obtained from high fidelity Computational Fluid Dynamics (CFD) modeling. Regarding the acoustic behavior of the LBSSA, Carlson’s simplified method is employed, which is based on the equivalent area distribution of the aircraft, in order to provide representative trends and results in the conceptual design phase. Finally, the contribution of the examined design parameters, in the aerodynamic and acoustic performance of the resultant LBSSA is presented and clear trends are indicated.
Aerodynamic Investigation of the High-Lift Performance of a Propeller-Driven Regional Transport Aircraft with Distributed Propulsion
Authors: Keller Dennis
Published: June 2023

Increased high-lift capabilities due to propeller slipstream, i.e. slipstream deflection, is seen to be one of the main benefits of distributed propulsion, as it may lead to a reduction in the main wing size and thus to reduced drag in cruise flight and/or reduced system weight and complexity. The presented work assesses the potential of distributed propulsion on the high-lift capabilities of a novel transport aircraft design from an aerodynamic point of view. The assessment is based on a regional propeller-driven transport aircraft designed within the European IMOTHEP project. Based on the initial aircraft design, a sensitivity study on the number of propellers and propeller positions with regards to the maximum lift coefficient under take-off conditions has been performed. Moreover, adjustments to the nacelle design and the propulsor integration have been investigated. The study indicates significant increases in the maximum effective lift coefficient in take-off of up to +42% due to slipstream deflection. The increase is thereby strongly dependent on the number of propellers and the propeller positions.
The environmental impact assessment of greener trajectories: the GreAT project
Authors: Alonso Gustavo , Benito Arturo
Published: June 2023

GreAT (Greener Air Traffic Operations) is a project funded by the European Commission under the H2020 framework programme. The overall objective is to reduce the fuel consumption and gas emissions during “gate-to-gate” flight phases through developing and assessing environment-friendly air traffic operational concept, adaptive airspace and green trajectory optimization technologies, and supporting avionic systems. Based on the scientific description of the impact of aviation emissions on the climate, the work within GreAT is seeking the key factors of the impact about aviation emissions on climate change characteristics by using sensitivity analysis, such as greenhouse gases, pollutant gases and condensation, and then select these factors as environmental impact assessment indicators, including fuel consumption, aviation emissions, air quality and greenhouse effect, establishing a calculation model for evaluation indicators using the fuel consumption model, gas emission model and climate change model. System analysis methods are used to build an aviation emission environmental impact (EIA) assessment index system structure, apply environmental impact assessment indicators, construct a general environmental impact assessment index system, and propose a comprehensive assessment method for aviation environmental impact. The following step in the project is the environmental impact assessment of air traffic operations to determine how green air traffic performs. According to the existing air traffic operation patterns, the flight characteristics and trajectory characteristics of the aircraft are determined, and the environmental impact assessment index system is used to evaluate the environmental impact under the air traffic operation plan and the impact and improvement effect on climate change.
Case study on hybrid-electric aircraft designs enabled by an enhanced SUAVE version
Authors: Eisenhut D , Mangold J , Moebs N , Brenner F , Strohmayer A
Published: June 2023

Hybridization seems to be a promising way for regional aircraft to reduce the climate impact of aviation in its sector. On the one hand, fully-electric propulsion offers a too limited range while on the other hand, a conventional powertrain cannot offer enough reduction in emissions. In this paper, a case study on hybrid-electric aircraft is performed enabled by an enhanced SUAVE version. A variation on several parameters is carried out for one exemplary hybrid-electric architecture: battery technology level, energy management strategies, hybridization of installed power, cruise speed and altitude. From this study a baseline design, focused mainly on environmental aspects, is selected. The impact of NOXemissions is improved by 83 % compared to the ATR 42, while CO2has a 5 % benefit without accounting for the net-effect of sustainable aviation fuels which is not part of this study.
Investigation of the operational flexibility of a regional hybrid-electric aircraft
Authors: Spinelli Andrea , Krupa Gustavo Pedro , Kipouros Timoleon , Berseneff Boris , Fiette Sébastien
Published: June 2023

The complexity of hybrid-electric aircraft propulsion systems is also characterized by the greater number of degrees of freedom of the energy management system, whose objective is to split the required power to fly the aircraft to the different available powertrains (i.e., gas turbines, electric motors, fuel cells, etc.). Typically, a single design mission is considered for assessing the performance of a hybrid-electric propulsion system, often with a simple constant split power between the batteries and gas turbine. A probabilistic set-based design space exploration methodology is used and allows us to study the effects of lifecycle analysis of the battery pack of a hybrid-electric 50-seater turboprop, while different mission scenarios are considered. Using this approach, it is possible to flexibly find multiple families of energy management strategies that can satisfy battery capacity requirements and the reduction of emissions simultaneously. Furthermore, the generated data can help the designers to understand the hierarchy of the requirements that drive the design of the propulsion system for a range of operating scenarios, with emphasis on the energy storage system. Hence, the airliners are offered enhanced operational flexibility of the aircraft for different and desirable mission profiles.
Preliminary hybrid-electric aircraft design with advancements on the open-source tool SUAVE
Authors: Mangold J , Eisenhut D , Brenner F , Moebs N , Strohmayer A
Published: June 2023

The large variety of possible propulsion architectures for environmentally friendly and sustainable aircraft concepts create opportunities for the overall aircraft design. In particular, hybrid-electric aircraft have an increased number of additional components that must be implemented in the aircraft design tool. Primary and secondary energy sources can be used to achieve the necessary reduction in emissions. The preliminary aircraft design tool SUAVE offers the basic setup necessary to integrate the electrification of the propulsion system into the aircraft design. For this purpose, SUAVE has been extended to enable an iterative sizing loop for hybrid-electric aircraft. Hence, many propulsion architectures are easily adaptable. Additional components can be included and their interactions are considered. Furthermore, the fidelity levels of the models are modifiable. Moreover, the top-level aircraft requirements are transformed into a sizing chart to calculate the necessary power and wing loading. Thereby, a reasonable hybridization factor of installed power can be identified. This definition of hybridization implies a specific energy management strategy. As a result, hybridization and the energy management strategy are directly coupled and have to be considered together. Finally, in the postprocessing, the raw data is processed and can be evaluated with figures of merit. This procedure converts the results into a descriptive value and facilitates the comparison to other configurations. The figures of merit include evaluations for emissions, operational aspects and development costs and effort.
Modeling the electrical part of an aeronautical EMA using Simscape
Authors: Quattrocchi Gaetano , Dalla Vedova Matteo D.L. , Maggiore Paolo , Giordano Raffaele
Published: June 2023

The present paper contains an analysis of the operation of the electric motor of an aerospace electromechanical servomechanism present on a test bench. Particularly, the description focuses on the electromagnetic phenomena of the three-phase stator circuit and the switching of the stator phases as a function of the applied control logic and rotor position. The activity was made possible through the construction and validation of a ‘digital twin’ physical model in the Simscape environment, which faithfully reproduces the behaviour of a High-Fidelity numeric reference model, built in the Simulink environment, perfectly representative of the electromechanical servomechanism. The recourse to the construction of a ‘digital twin’ physical model was necessary as it allows the study of non-linear phenomena that are the main cause of failures of electromechanical servomechanisms. Therefore, the analysis conducted will allow prognostics algorithms to be developed in order to predict potential failure conditions and avoid potential hazardous situations in the operating environment.
An interactive framework to facilitate probabilistic set-based multidisciplinary design optimisation studies
Authors: Krupa Gustavo P. , Spinelli Andrea , Kipouros Timoleon
Published: June 2023

The upcoming stringent environmental aircraft regulations and the environmental, social and governance (ESG) framework targeting net zero emissions has forced aircraft manufacturers to seek innovative feasible technical solutions. Often, there is the need to consider entirely radical solutions, such as hybrid-electric aircraft, which are not fully understood when compared with conventional kerosene driven aircraft. The recent development of a probabilistic set-based multidisciplinary optimisation methodology has demonstrated the ability to explore trade-offs when the requirements are uncertain. In this way, the weaknesses and potential to enable the feasibility of hybrid-electric aircraft can be studied from a systems perspective but maintaining the connection with more detailed trade-off studies of components of the sub-systems. We have developed an interactive interface, where the user is guided through the steps of the design methodology and the produced data is visualised to aid an informative decision-making process. In our illustrative case study, decision-makers are enabled to interactively explore the hybrid-electric propulsion design space while considering the impact to the figures of merit from expected improvements in the coming years of key enabling technologies, such as energy storage.
Effect of 3D blade design on the aerodynamic, aeroelastic and structural behavior of a scaled UHBR fan
Authors: Eggers Torben , Friedrichs Jens , Goessling Jan , Seume Joerg R. , Flüh Jan , Lindemann Jens , Paletta Nicola
Published: June 2023

In this paper, the effect of a 3D blade design on the aerodynamic, aeroelastic and structural behavior of a scaled UHBR fan is investigated numerically. First, an initial sensitivity analysis for the geometrical design features sweep and lean as well as an adaption of the thickness position in the fan hub region is conducted. Positive sweep is found to benefit the total pressure ratio, while positive lean improves the polytropic efficiency of the fan stage. Moving the maximum thickness position upwards leads to decreased flow turning and total pressure ratio.

The mode shape and by that the twist-to-plunge ratio of the first mode is significantly influenced by the modifications. Thus, changing the aerodynamic damping of the blade and influencing the flutter behavior of the fan.

Additionally, the fan displacements under aerodynamic and rotational loads are affected. For the fan presented a positive lean causes the blade to bend towards the pressure side when subjected to inertial forces, countering deformation from aerodynamic loads. Thickness adaption moves the shear center of the cross sections to the back. These results are used to optimize the fan blade behavior to achieve the project’s objectives. A final design, which satisfies the aerodynamic, aeroelastic and structrual needs of the CA3ViAR fan stage, is presented.
Hybrid Strategies for the Improvement of the Flame Retardancy of in-situ Silica-Epoxy Nanocomposites cured with Aliphatic Hardener
Authors: Bifulco A , Imparato C , Gaan S , Malucelli G , Aronne A
Published: June 2023

The aerospace industry requires materials showing good mechanical performance, durability, and thermal stability to satisfy very stringent requirements in several applications. Epoxy-based composites can be a suitable solution, due to the peculiar characteristics of the polymer matrix. Epoxy resins can be cured by aliphatic or aromatic hardeners. The use of aliphatic amines is preferable because of their lower toxicity, though these curing agents are easily flammable. Recently, hybrid systems conjugating in-situ modified epoxy matrix with organic and inorganic additives have been developed to flame retard aliphatic epoxy composites. This short review summarizes some applications of such strategies, which are based on the use of the sol-gel technique, DOPO-based flame retardants, bio-waste compounds and other synergists. The review describes the main concept of this approach and the preparation of no-dripping self-extinguishing silica-epoxy hybrid composites showing low phosphorus loadings, tailored interphases and good mechanical properties.
Joining of Composites with Metals using Graded Metal Fabric Interfaces
Authors: Grothe Richard , Weck Daniel , Sennewald Cornelia , Troschitz Juliane , Gude Maik , Cherif Chokri
Published: June 2023

A major challenge in the implementation of fibre-reinforced plastics (FRPs) is the provision of stress-appropriate joints with other materials. Establishing a high-strength, graded metal fabric interface using industrially established joining methods is a target-oriented approach in this context. For this purpose, a novel solution based on a textile transition structure in combination with the evaluation of different joining methods is presented in this article. A process chain was developed that depicts both the design and production of textile transition structure as reinforcement material of the FRP component and the further processing to metal FRP composites. Within the textile transition structure, the hybrid fabrics combine glass fibre yarns and metal flat wires, where the latter enable the joining process and transfer loads into the reinforcing glass fibres. The manufacturing implementation of this new joining interface from the textile to the hybrid component is described in detail within the paper. Furthermore, results of mechanical load tests of the graded metal fabric interface are presented. The research results make a significant contribution to the development of innovative graded metal fabric interface with a benign failure behaviour and a great potential especially with regard to the efficient joining of mixed material constructions in large-scale applications.
Sustainable scrapping method of thermoplastic composite materials
Authors: Ruiz R , Llácer M , Sandá A , Ander J , Halm J , Sterk S
Published: June 2023

In this work, a novel method for more sustainable recycling and cost-efficient manufacturing technique of thermoplastic composite materials is proposed to recover and reprocess waste and end-of-life materials in aerospace industry. For the recycling of carbon fibre reinforced thermoplastics, an innovative scrapping process based on mechanical cutting has been developed and the properties of the obtained scrap and the recycled panel have been analysed. Thus, a cutting tool has been developed for the delamination of the input material with the aim of retaining long fibres in the resulting scrap. Different processing approaches of material scrapping have been evaluated aiming to obtain manageable scrap that can be subsequently used for a compression moulding process. Additionally, an automatic process has been evaluated to manage the scrap and perform the corresponding lay-up to manufacture high-quality thermoplastic composite products with recycled materials. Tensile strength and elasticity modulus properties were tested, and results were discussed. Finally, the life cycle assessment of the new process technology was conducted.
Identification of circular eco-subsystems for end-of-life aviation composite components based on a systematized R6-strategy
Authors: Johst P , Kucher M , Schulz P , Knorr A , Kupfer R , Böhm R
Published: June 2023

The demand of composites in the aviation and space industry has increased significantly in recent decades. This is due to the excellent properties of composite materials, especially their low density and design flexibility. However, the reuse and further utilization of composite structures and their materials provide new challenges for the recycling sector. In accordance with the ‘Green Deal’ of the European Commission, new pathways are required to ensure an effective and economic reuse of composite components at their end-of-life (EoL). We discuss a strategic approach for returning decommissioned parts of aviation composites back into the material cycle with a particular focus on waste reduction, as well as the decrease of the associated energy demand and emissions. Therefore, a sustainable strategy to exploit various circular possibilities was applied, consisting of the six R-strategies:reuse, repair, refurbish, remanufacture, repurposeandrecycling. The Multi-Tiered System of Support is transferred to the introduced R6-strategy. The concept provides an approach to address the challenges of reintroducing EoL composites into the material chain. Based on the systematized R6-strategy it was possible to identify circular eco-subsystems for aviation composite components with minimal effort. Finally, this paper discusses a potential criterion used for assigning EoL aviation composites to the various eco-subsystems.
Air Ejector Analysis in Extended Operational Perimeter for Control Oriented Simulation of Bleed-Air Aircraft Systems
Authors: Eugenio Schillaci , Carles Oliet , Babu Vemula Jagadish , Matthieu Duponcheel , Yann Bartosiewicz , Philippe Planquart
Published: June 2023

The integration of large size Ultra High Bypass Ratio (UHBR) engines introduces new restrictions of space for their integration with the aircraft wing. Under this scenario, a reduction of the size of the bleed air system and particularly of the pre-coolers is requested. The current research aims to introduce air-air ejectors as a potential solution. A combined methodology based on experimental and CFD analyses is proposed to obtain physical insights and validation material for the development of a robust and accurate lumped model, capable of simulating the static and dynamic ejector behaviour in normal and abnormal conditions. In this paper, an overview on the performed initial activities on the dynamic aspects is provided.
Data acquisition unit for suborbital rocket vibration measurement
Authors: Wojciechowski K , Graczyk H , Piwowarczyk M , Truszkowski R , Rękawek P
Published: June 2023

Suborbital rockets and space launch vehicles experience high levels of vibration. They are caused by various factors, such as aerodynamic effects on the external surfaces and engine combustion instability. The second factor is especially pronounced in hybrid rocket engines, such as the main engine of the ILR-33 AMBER 2K rocket. In order to ensure the correct operation of all the equipment and payload on board, vibration testing of the devices is necessary as part of pre-flight qualification. For such tests to be truly indicative of in-flight performance, the vibration environment of the vehicle must be analysed. A conceptual measurement method was proposed, along with a prototype measurement system. The system is adapted to be integrated into the modular ILR-33 AMBER 2K on-board computer or work independently as a separate module. The device measures vibration in three axes in several key points onboard the rocket, with the possibility of connecting multiple units in a daisy-chain configuration. This paper presents the design of the module, including the key aspects of integrating it as part of the avionics package. The means of acquiring and storing of measurement data are presented. The method of validating the system’s data acquisition capabilities is described in detail. Qualification testing results and identified issues are discussed. Possible future improvements are proposed.
Enhancement of the Advanced Weather Awareness System for the development of an Integrated Mission Management System in the COAST project
Authors: Zollo A L , Montesarchio M , Ferrucci M , Bucchignani E , Cinquegrana D
Published: June 2023

The COAST (Cost Optimized Avionics SysTem) project, funded by Clean Aviation Joint Undertaking, works toward the realization of cost-effective key technologies for cockpit and avionics of Small Air Transport (SAT) aircraft. In 2020 the design of a new technology started, the Integrated Mission Management System (IMMS), devoted to automatically optimize the trajectory while considering air-traffic, weather conditions, terrain and obstacles. It is aimed to implement into a unique system the functionalities of Trajectory Planning, Flight Reconfiguration, Tactical Separation and Weather Awareness, benefitting from the integration and interaction on-board of three technologies, individually developed and tested in the first phases of the COAST project: Flight Reconfiguration System (FRS, managing pilot’s incapacitation emergency), Tactical Separation System (TSS, managing tactical traffic separation and enhanced situational awareness) and Advanced Weather Awareness System (AWAS, devoted to provide on-board updated weather data). The present work focuses on the last one and more in detail on the description of new functionalities introduced to the baseline AWAS system, already demonstrated in flight in 2021, in order to allow its integration in IMMS. Specifically, enhancements to the AWAS technology were required to integrate new input weather data and generate additional information, needed for IMMS purposes. These data are produced on-ground and sent through satellite link to the AWAS on-board segment, which has been updated to manage and exchange them with the other components on the aircraft. All the achieved progresses in the development of the evolved version of the AWAS system presented in this work will be demonstrated and tested in flight during a dedicated campaign planned in 2023 in the framework of COAST project.
Hybrid Navigation Prototype for Small Aircraft Transportation Vehicles
Authors: Vaispacher Tomas , Baranek Radek , Malinak Pavol , Kucera Matej
Published: June 2023

The Small Aircraft Transportation (SAT) segment represented mainly by helicopters, piston fixed-wing aircraft, turboprop aircraft, and business jets requires a reliable source of navigation information with an appropriate price. This paper describes the research and development activity funded by Clean Sky 2 Cost Optimized Avionic Systems (COAST) development program targeting affordable hybrid navigation solutions. The affordability is driven by size, weight, and power consumption (SWAP) requirements. The desired level of accuracy, integrity, and availability is being achieved by a hybrid navigation solution based on GPS/INS fusion extended by other navigation sensors. The hybrid core of the systems uses GPS with SBAS augmentation to outperform standard tightly coupled GPS-based hybrid systems. The purpose of this article is to describe the current state, algorithmic structure, and hardware maturity of the navigation system prototype. The paper describes individual hardware components, points to the resulting prototype, and summarizes tests in a representative environment. The ultimate goal is to demonstrate the overall performance of the hybrid system based on a low-cost micro-electro-mechanical system (MEMS) Inertial Measurement Unit (IMU). The low-cost inertial sensor is one of the key components securing the affordability of the proposed system, so its testing plays important role. Another assumption considered in the system design was integration of standardly-used onboard sensors. For this purpose, the hardware prototype was tested in a demonstrative and outdoor environment. The results of this exercise are summarized in this paper.
Preliminary weight estimation of canister based light foldable wing electric propulsion UAV, as a platform for swarm applications
Authors: Karatzas E , Kostopoulos V , Lappas V
Published: June 2023

Lots of disruptive UAV technologies are rising every day. Especially in the design process, under the prism of the upcoming swarm trend, a novelty touch to new foldable designs has started. In combination with electric propulsion systems, those platforms come in reality. Because of their size, the same design can be enlarged and reduced with minor changes at its subsystems. This simplifies the construction process and minimizes the costs. Due to their application range both, civilian and military platforms started to develop their own foldable UAVs, basically for swarm applications. In this study, the basic parameters of such a scalable design will be proposed. A literature survey will be presented, to determine the most common sizes of those platforms and the battery market availability. Afterwards, a mission profile will form the basis of the conceptual process for different dimensional UAVs. Two different methods about the weight estimation of the UAV will be examined. The goal of this multilateral examination is that; enable the designer to precede to an appropriate selection of subsystems of the UAVs, i.e., battery, autopilot and telemetry systems based on the weight estimation.
A Drone Secure Handover Architecture validated in a Software in the Loop Environment
Authors: Filho Enio Vasconcelos , Gomes Filipe , Monteiro Stéphane , Severino Ricardo , Penna Sergio , Koubaa Anis , Tovar Eduardo
Published: June 2023

The flight and control capabilities of uncrewed aerial vehicles (UAVs) have increased significantly with recent research for civilian and commercial applications. As a result, these devices are becoming capable of flying ever greater distances, accomplishing flights beyond line of sight (BVLOS). However, given the need for safety guarantees, these flights are increasingly subject to regulations. Handover operations between controllers and the security of the exchanged data are a challenge for implementing these devices in various applications. This paper presents a secure handover architecture between control stations, using a Software in the Loop (SIL) model to validate the adopted strategies and mitigate the time between simulation and real systems implementations. This architecture is developed in two separate modules that perform the security and handover processes. Finally, we validate the proposed architecture with several drone flights on a virtual testbed.
Vision-Based Real-Time Motion Estimation of Ground Vehicles from Aerial Imagery
Authors: Kurt Yagiz , Soken Halil Ersin
Published: June 2023

This research presents vision-based maneuvering object motion estimation in case of occlusion. Unequal dimension Interactive Multiple Model (UDIMM) approach is applied to increase the motion prediction accuracy when no measurement is available. Current deep learning-based multi-object tracking algorithms cannot track the objects when an occlusion exists, even for quite a short time. The main reason is the motion model used in tracking algorithms. If the measurement coming from the object detector is not available, the prediction model propagates the Kalman Filter’s motion model. In this period, the object may maneuver or accelerate/decelerate so that the tracker cannot assign the tracklets successfully. Eventually, the ID switch occurs, and object tracking gets lost. Using the UDIMM approach, track loss due to the ID switch is highly reduced compared to the simple constant velocity motion model used in the StrongSort multi-object tracker algorithm. A two-dimensional simulation environment is created to compare the ground truth data with the estimation results. Performance results of different filters are compared.
A Drone Operation Plan model to support the effect of uncertainty in advanced U-Space Capacity Planning Process
Authors: Büddefeld M , Crook I , Eduardo Teomitzi H , Kleikemper J , Picot T , Sanchez P , Seprey Y
Published: June 2023

Enabling high numbers of drone operations in urban environments will require an efficient and highly automated drone traffic management system that can help balance demand against novel capacity measures. The research project DACUS designed a new, social impact-and risk-based Dynamic Capacity Management (DCM) service. As a core element, Drone Operation Plans (DOP) as the central and reliable point-of-information must include all necessary information for the DCM service to evaluate and manage the demand and the associated uncertainty of those operations at various phases of the operations planning process.

This paper introduces a model to define and share DOPs that are enriched with information about technical capabilities of the drone, variations in the operating environment and the operational characteristics of each particular mission which helps facilitating the drone traffic management in capacity-constrained scenarios. The model aims to capture varying degrees and sources of uncertainty regarding the planned operations. Additionally, the model supports the integration of resolution plans to cope with a wide range of off-nominal scenarios and contingency events.

For evaluation, the proposed DOP model is implemented and used in experiments embedded in Sopra Steria’s UTM or U-space Collaborative Interface System (UCIS). A social impact model and a collision risk model are used in simulations with high traffic demand and the information of the DOPs is either updated or directly applied within the DCM processes. The influence of operational uncertainty is assessed in this work using the collision risk model, which evaluates the risk of drone operations to the public and identifies potential collision risk hotspots.

The simulation results show that the DOP model is suitable for the requirements of several U-space services and functions.
BUBBLES: A new concept of operations for separation management in the U-space
Authors: Puchol Cecilia Claramunt , Vélez Norberto Vera , Tejedor Juan Vicente Balbastre , Vila Carbó Joan A.
Published: June 2023

BUBBLES (Defining the building basic blocks for a U-space separation management service) is an Exploratory Research project funded by SESAR Joint Undertaking (SJU) that aims to define a new Concept of Operations (ConOps) to provide separation management by means of the U-space. In the context of this project, this work defines the principles on which separation management in the U-space is based, as well as the basic building blocks that support the separation management service and how they should be assembled and operated. One of the most important challenges in conflict management is the selection of appropriate separation minima. In this sense, this work proposes the calculation of dynamic separation minima, which are adapted to the traffic class, the operational environment, and the Communication, Navigation, and Surveillance (CNS) systems performance, and validates it by means of test-flights in a rural environment.
The temperature and drift law of hot spots of oil-immersed air-cooled power transformers
Authors: Ye Liu , Xin Yang , Jia Pengfei
Published: June 2023

This paper carries out three-dimensional transient simulation calculation of hot spot distribution of oil immersed air-cooled transformer under different working conditions based on the finite element method, couples the electromagnetic loss calculation result unit to the temperature field, and takes it as the heat source to establish the mapping relationship of magnetic heat flow multi physical field. Taking SFZ11-30000/110 transformer as an example, the temperature distribution and hotspot position under different working conditions are obtained. By comparing the results of the heating test, the effectiveness of the simulation model is verified. Studies have shown that as the load increases, the position of the hotspot shifts along the wind axis. After the fan is turned on, there is also an axial upward drift of about 3% at the hot spot, which provides a method basis for the winding insulation and heat dissipation design of oil immersed air-cooled power transformer.
Annual Contribution Electricity Forecasting Model Based on Logistic Regression Analysis
Authors: Lai Guoshu , Wu Guoyao , Lan Zhiqiang , Wu Xiaofang , Xia Sihui
Published: June 2023

Due to the complex characteristics of the annual contribution time series, it is difficult to achieve the ideal prediction effect by a single prediction. Therefore, the annual contribution electricity prediction model based on Logistic regression analysis is studied. The statistical method of time series analysis combined with the fuzzy correlation feature analysis method is used to obtain the high-voltage power transmission data of business expansion and the power consumption data after power transmission. We use the fuzzy clustering theory to complete the customer segmentation and accurately locate the same type of user groups. On this basis, we preprocess the characteristic data of the annual contribution electricity forecast and build the annual contribution electricity forecast model based on Logistic regression analysis to realize the annual contribution electricity forecast. The experimental results show that the proposed method has a good prediction effect of annual contribution power, and can effectively shorten the prediction time of annual contribution power.
Optimal design and performance analysis of Rotating Power Flow Controller
Authors: Yan Xiangwu , Li Yuzhen , Lian Kaige
Published: June 2023

In this paper, a scheme of rotating power flow controller (RPFC) is proposed, which can flexibly and effectively reduce the voltage deviation under the disturbance of distributed generation and load side. Firstly, based on the prototype of a new rotating power flow controller (RPFC) with a rated capacity of 40 kVA, a two-dimensional finite element model based on the core component RPST is established. Then the optimal parameter combination in RPST is determined by the Taguchi experiment method and weight calculation. Finally, Matlab, Maxwell, and Simplorer are used to realize the joint simulation of field-circuit coupling. The results show that the voltage regulation efficiency and power factors of RPFC are increased by 1.4% and 2.7% respectively under the optimal parameter combination, which provides a reference for the design and engineering application of large-capacity RPFC.
Electric Heating System of Residences without Central Heating: Power Supply Optimization
Authors: Sun Zijing , Zhu Qunzhi , Fu Zaiguo , Tian Xi , Yang Changhai , Wei Yong , Liu Zhengying
Published: June 2023

For conservation and environmental purposes, three electricity consumption models, power grid, power grid + PV and power grid + PV + battery, are proposed in this paper, the optimization of the electric heating energy consumption model is carried out with the objective of the highest annual net return of the system. The results showed that for the single-layer residence with a housing area of 100m2, the use of the power grid + photovoltaic system has the highest annual net income, as well as good economic and environmental benefits.
A Novel Operating Indexes Calculation Method for Distribution Network with High PV Penetration
Authors: Fan Hongjin , Sun Kaiqi , Ning Dalei , Li Peihao , Zhu Fengju , Dong Yuqing
Published: June 2023

High proportion of distributed photovoltaic power generation (PV) generally exists in the distribution network (DN). However, high PV penetration leads to power factor reduction, power quality decline, line loss changes, and other problems. Generally, most indexes in the power system are calculated according to the parameter conditions of the main network (MN), which means X>>R is set by default. However, it is different between the line parameters of the MN and the DN, causing significant errors in the calculation of the DN using the MN conditions (X>>R). This paper examines the causes and processes of the changes in the critical indexes caused by the incorporation of a high proportion of PV into the DN, such as grid-connected voltage and line loss, based on the different line parameter conditions between the MN and the DN. Considering the DN condition (X>>R is not tenable), a novel calculation method of main operating indexes for the DN with high PV proportion is proposed. Finally, a numerical model built on an actual DN is used to verify the conclusion by comparing the difference in the change process of the main indexes generated by the calculation based on the MN condition and the novel calculation method in the event of high PV penetration in the DN.
Fast time response detectors of alpha particles fabricated using CVD diamonds
Authors: Hou Qingfeng , Wang Tianning , Zhao Rui , Tang Jun , Qin Li , Ma Zongmin , Liu Jun
Published: June 2023

Diamond with extraordinary properties, such as fast
response, and extremely high thermal conductivity, is an ideal
choice for the next generation radiation detectors. In this paper, a
radiation detector based on a single crystal CVD diamond
(3 mm × 3 mm × 200 μm) with
(100) orientation is proposed to detect α radiation. The
detector employs gold films on the diamond as an electrical contact,
and the origin-symmetric current-voltage characteristics
demonstrated excellent Ohmic contact behavior. At an electric field
of 0.4 V/μm, a current dark value of 4 nA was measured. The
detector's pulse speed was tested using 5.486 MeV 241Am
sources. The time response of the detector to α particles
is fast, with a rise time of 260 ps, a fall time of 650 ps, and a
pulse width of 1.6 ns. These findings indicate that the detector
can be used as a sensor for α radiation.
Arctic amplification has already peaked
Authors: Davy Richard , Griewank Philipp
Published: June 2023

It has been demonstrated that the Arctic has warmed at almost four times the global average rate since 1979, a phenomenon known as Arctic amplification. However, this rapid Arctic warming is tightly linked to the retreat and thinning of summer sea ice, and so may be expected to weaken as the Arctic transitions to seasonal ice cover. Here we show evidence from gridded observations and climate reanalysis that Arctic amplification peaked sometime in the early 2000s. This occurred concurrently with a maximum in the rate of loss of sea ice area, thickness, and volume. From CMIP6 projections and the CESM2 large ensemble we see that Arctic amplification is unlikely to be so high again at any future point in the 21st century except in the lowest emissions scenarios in which global temperatures stabilize while the Arctic continues to warm.
A conceptual design of a thermal switch capacitor in a magnetocaloric device: experimental characterization of properties and simulations of operating characteristics
Authors: Petelin Nada , Kalin Mitjan , Kitanovski Andrej
Published: June 2023

The quest for better performance from magnetocaloric devices has led to the development of thermal control devices, such as thermal switches, thermal diodes, and thermal capacitors. These devices are capable of controlling the intensity and direction of the heat flowing between the magnetocaloric material and the heat source or heat sink, and therefore have the potential to simultaneously improve the power density and energy efficiency of magnetocaloric systems. We have developed a new type of thermal control device, i.e., a silicon mechanical thermal switch capacitor (
TSC). In this paper we first review recently developed thermal switches based on micro-electromechanical systems and present the operation and structure of our new TSC. Then, the results of the parametric experimental study on the thermal contact resistance, as one of the most important parameters affecting the thermal performance of the device, are presented. These experimental data were later used in a numerical model for a magnetocaloric device with a thermal switch-capacitor. The results of the study show that for a single embodiment, a maximum cooling power density of 970 W m−2 (510 W kgmcm
−1) could be achieved for a zero-temperature span and an operating frequency of 5 Hz. However, a larger temperature span could be achieved by cascading multiple magnetocaloric elements with TSCs. We have shown that the compact TSC can be used in caloric devices, even with small temperature variations, and can be used in a variety of practical applications requiring thermal regulation.
iAMPCN: a deep-learning approach for identifying antimicrobial peptides and their functional activities
Authors: Xu Jing , Li Fuyi , Li Chen , Guo Xudong , Landersdorfer Cornelia , Shen Hsin-Hui , Peleg Anton Y , Li Jian , Imoto Seiya , Yao Jianhua , Akutsu Tatsuya , Song Jiangning
Published: June 2023

Antimicrobial peptides (AMPs) are short peptides that play crucial roles in diverse biological processes and have various functional activities against target organisms. Due to the abuse of chemical antibiotics and microbial pathogens’ increasing resistance to antibiotics, AMPs have the potential to be alternatives to antibiotics. As such, the identification of AMPs has become a widely discussed topic. A variety of computational approaches have been developed to identify AMPs based on machine learning algorithms. However, most of them are not capable of predicting the functional activities of AMPs, and those predictors that can specify activities only focus on a few of them. In this study, we first surveyed 10 predictors that can identify AMPs and their functional activities in terms of the features they employed and the algorithms they utilized. Then, we constructed comprehensive AMP datasets and proposed a new deep learning-based framework, iAMPCN (identification of AMPs based on CNNs), to identify AMPs and their related 22 functional activities. Our experiments demonstrate that iAMPCN significantly improved the prediction performance of AMPs and their corresponding functional activities based on four types of sequence features. Benchmarking experiments on the independent test datasets showed that iAMPCN outperformed a number of state-of-the-art approaches for predicting AMPs and their functional activities. Furthermore, we analyzed the amino acid preferences of different AMP activities and evaluated the model on datasets of varying sequence redundancy thresholds. To facilitate the community-wide identification of AMPs and their corresponding functional types, we have made the source codes of iAMPCN publicly available at https://github.com/joy50706/iAMPCN/tree/master. We anticipate that iAMPCN can be explored as a valuable tool for identifying potential AMPs with specific functional activities for further experimental validation.