bluuebunny/crossref_metadata_2025 huggingface dataset:
Kadın Futbolcuların Bazı Performans Testleri ile Maç Performans Parametreleri Arasındaki İlişki
Authors: BAŞKAYA Gizem , AKKOYUNLU Yağmur
Published: June 2023

Bu çalışmanın amacı, kadın futbolcuların bazı performans test sonuçları ile müsabaka performansı arasındaki ilişkiyi araştırmaktır. Çalışmaya kadınlar süper liginde mücadele eden 24 kadın futbolcu (yaş: 25.21±5.532 yıl; antrenman yaşı: 12.33±5.027 yıl; boy uzunluğu: 168.58±3.450 cm; vücut ağırlığı: 59.89±5.736 kg) gönüllü olarak katılmıştır. Katılımcılara squat jump, countermovement jump, 10m ivmelenme, 30m sürat, Yoyo Aralıklı Toparlanma Testi ve 30-15 Aralıklı Fitness Testi testleri uygulanmıştır. Müsabaka sırasında sporcuların hareket analizleri Fitogether GPS ile kaydedilmiştir. Hareket analizleri kapsamında maçta kat edilen toplam koşu mesafesi, yüksek şiddetli koşu mesafesi ve sayısı, sprint mesafesi ve sayısı, maksimal sprint hızı, ortalama hız, akselerasyon ve deselerasyon sayıları değerlendirilmiştir. Parametreler arasındaki ilişki düzeyini belirlemek amacıyla Pearson Korelasyon analizi kullanılmıştır. Analizler sonucunda, sporcuların Yoyo-1 koşu mesafesi ve Yoyo-1 bitirme hızı ile müsabakada toplam kat edilen mesafe arasında orta düzeyde pozitif yönlü ilişki (r=485; r=.423); 30-15 IFT koşu mesafesi ve sayısı ile müsabakada toplam kat edilen mesafe arasında orta düzeyde pozitif yönlü ilişki olduğu (r=.431; r=.409) bulunmuştur. HSR sayısı ile 30 m sürat performansı arasında orta düzeyde negatif yönlü (r=-.431); ortalama hız ile 30 m sürat performansı arasında orta düzeyde pozitif yönlü (r=-.419); maksimal sprint hızı ile CMJ ve SJ arasında orta düzeyde pozitif yönlü (r=.448; r=.474) ilişki tespit edilmiştir (p
The Kinematic Bimodality: Efficient Feedback and Cold Gas Deficiency in Slow-rotating Galaxies
Authors: Wang Bitao , Peng Yingjie
Published: June 2023

The bimodality in the stellar spin of low-redshift (massive) galaxies, ubiquitously existing at all star formation levels and in diverse environments, suggests that galaxies grow and quench through two diverged evolutionary pathways. For spheroid-dominated galaxies of slow stellar rotation, the age composition and metallicity of their stellar populations are evidence of a fast quenching history with significant gas outflows. In this work, we measure the spin parameter

λ

R

e

, i.e., the normalized specific angular momentum of stars, out of the MaNGA integral field spectroscopy for about 10,000 galaxies. Among the two-thirds with H i follow-up observations (z ≲ 0.05), we find that, compared to fast-rotating galaxies of the same stellar mass and star formation, the galaxy populations with slower rotation are generally more H i gas-poor, robust against further environmental restriction and with nondetections properly taken into account using the stacking technique. This cold gas deficit of slow-rotating galaxies is most apparent at high mass

∼

10

11



⊙

below the star formation main sequence, supporting the pivotal role of gas outflows in their quenching history. With hints from H i velocity distributions, we suspect that massive gas outflows among the slow-rotating population are facilitated by high ejective feedback efficiency, which is a result of extensive coupling between disturbed volume-filling cold gas and (commonly) biconical feedback from central black holes. By contrast, in fast-rotating disk galaxies the feedback energy mostly goes to the hot circumgalactic medium rather than directly impacting the dense and planar cold gas, thus making the feedback mainly preventive against further gas inflow.
A new approach to the study of fixed points based on soft rough covering graphs
Authors: Khan Imran Shahzad , Shah Nasir , Shoaib Abdullah , Kumam Poom , Sitthithakerngkiet Kanokwan
Published: June 2023

Mathematical approaches to structure model problems have a significant role in expanding our knowledge in our routine life circumstances. To put them into practice, the right formulation, method, systematic representation, and formulation are needed. The purpose of introducing soft graphs is to discretize these fundamental mathematical ideas, which are inherently continuous, and to provide new tools for applying mathematical analysis technology to real-world applications including imperfect and inexact data or uncertainty. Soft rough covering models $ \left(\text{briefly}, \text{ }\mathcal{SRC}\text{-Models}\right) $, a novel theory that addresses uncertainty. In this present paper, we have introduced two new concepts $ \mathcal{L}\mathfrak{i} $-soft rough covering graphs ($ \mathcal{L}\mathfrak{i} $-$ \mathcal{SRCG} $s) and the concept of fixed point of such graphs. Furthermore, we looked into a some algebras that dealt with the fixed points of $ \mathcal{L}\mathfrak{i} $-$ \mathcal{SRCG} $s. Applications of the algebraic structures available in covering soft sets to soft graphs may reveal new facets of graph theory.
Exploring the Knowledge Sharing Dynamics in Virtual Communities Within the Metaverse Domain
Authors: Daradkeh Mohammad
Published: June 2023

This chapter aims to explore the knowledge sharing model in virtual communities within the metaverse domain and proposes a way to enhance knowledge sharing and innovation in these communities. The study takes into account the practical implications of digital ethics and digital citizenship and the impact they have on the shaping of digital ethics. Based on the analysis of relevant practices and prior research, a knowledge sharing model for virtual communities in the metaverse is constructed. The results show that the basic process of knowledge sharing involves the selection and acquisition of community knowledge in three dimensions, internalization and absorption of situational knowledge to form a “knowledge black box,” and finally, sharing through private domain knowledge broadcasting and diffusion. The current practices in virtual communities within the metaverse domain are limited and lack empirical evidence.
Strategic Management of Digital Transformation Processes in the Aviation Industry
Authors: Mızrak Filiz , Akkartal Gonca Reyhan
Published: June 2023

The Fourth Industrial Revolution has profoundly affected all sectors, quickly leading to significant technological changes. This new revolution has also affected aviation systems that have a direct connection with technology. This revolution has brought about rapid changes especially in airport systems and led to the emergence of the concept of “smart airport.” In this study, the case of Istanbul Airport has been analyzed in terms of digital transformation in order to exemplify the digital applications in an airport. In this scope, the aim of the study is to present a new projection, integrated with a digital business strategy, to businesses operating in the airline industry, where they can successfully realize the digital transformation process and manage this process strategically.
Impact of Sustainability on Supply Chain
Authors: Özkanlısoy Özden , Bulutlar Füsun
Published: June 2023

Industry 4.0 technologies, also called disruptive, have become a part of the new world. When disruptive technologies are investigated in terms of supply chain, they have many effects on supply chain performance. Sustainability is one of the positive contributions of these technologies to supply chain performance. When measuring supply chain performance, it is necessary to keep up with the times and therefore constantly update the performance measurements. Previous studies did not address the sustainability dimension of supply chain performance measurements comprehensively. In this chapter, the authors examine supply chain sustainability performance measurements based on the existing literature and taking into account the contributions of DTs to determine them. The authors briefly explain disruptive technologies and examine the contributions of these technologies to supply chain sustainability performance separately. The main aim of the study is to guide companies and their supply chains to enhance their supply chain sustainability performance by using disruptive technologies.
Social Media Communication and Sustainability Perception in Business
Authors: Amoako George Kofi , Coffie Isaac Sewornu , Ocloo Elikem Chosniel
Published: June 2023

Achieving the 17 sustainable development goals (SDGs) has become very important in the survival of the human race and the earth's ecosystem. The purpose of this study is to see the effectiveness of social media communication and how it influences consumer behavior perception on environmental sustainability and the role of social media influencers. This chapter is a conceptual manuscript. The researcher used literature from good and reliable databases such as Emerald, Sage, Taylor & Francis, Web of Science, Elsevier, and others. Desk research was adopted and literature covering the relevant constructs in the title and model were reviewed and thoroughly discussed and meanings and implications were synthesized.
The Role of Artificial Intelligence in Modern Finance and Sustainable Marketing
Authors: Wójcik-Czerniawska Agnieszka Jadwiga
Published: June 2023

Artificial intelligence (AI) is reshaping marketing and is becoming a capable assistant supporting many facets of the industry. Artificial intelligence plays a vital role in modern finance and sustainable marketing. AI can be utilized to improve sustainability and enhance financial services. The chapter begins with the assertion that contemporary finance and market viability are crucial components of every economy. The most recent disruptive technology is artificial intelligence (AI), which has the greatest potential to change marketing. International practitioners are trying to recognize the best AI results for their marketing functions. To build a more secure business and economic environment and lower human mistakes, the chapter demonstrates how artificial intelligence may combine contemporary finance and market sustainability with tech skills.
Big Data and Cloud Computing-Integrated Tourism Decision-Making in Smart Logistics Technologies
Authors: Lan Man
Published: June 2023

Since technology allows tourist companies to replace expensive human labor with electronic labor, labor expenses are reduced, yet customer service concerns are often avoided. Companies and organizations face new challenges daily. Increased consumer demands and global competition result in significant adjustments in the industrialized world. On the other hand, technology can bring forth entirely new types of unintended effects. There are new prospects for the tourist sector with the rise of big data. Data mining and cloud computing are widely used in the tourist sector to extract useful information from vast quantities of data. A new tourism marketing management model based on big data can be developed with this function. This research thus presents a big data and cloud computing-integrated tourism decision-making (BC2TDM) paradigm to analyze the behavior of travel consumers. This model uses the deep learning model to forecast the travel consumer behavior to ensure a personalized tourism experience.
Testing of a Fiber-Optical Sensor System for Rotor Blade HUMS
Authors:   Technical University of Munich, Berghammer Florian , Sosa Benedikt , Heuschneider Verena , Yavrucuk Ilkay , Hajek Manfred
Published: June 2023

As a prerequisite for the development of HUMS (Health and Usage Monitoring Systems) using blade displacement and sectional force estimation in forward flight, rotor blades are instrumented with fiber-optical sensors at the Institute for Helicopter Technologies and VTOL at the Technical University of Munich. Utilizing a total number of 60 directional strain measurements it is possible to reproduce the strain field of five sections along the uniform airfoil section. Knowing the exact location of the integrated sensors is crucial for shape reconstruction and may vary in reality due to a number of uncertainties occurring in chordwise and thickness direction of the airfoil profile during fabrication. Thermographic scan methods and computed tomography scans are investigated in order to determine the sensor locations inside the blade and to reproduce a 3D model of the integrated sensor system. Improvements can be seen when comparing results from static deformation tests using the sensor positioning from the layout and the real sensor positions investigated in computed tomography. In addition sectional stiffness terms are derived from strain measurements in combination with loadcell data. With the scope of state observation on the MERIT (Munich Experimental Rotor Investigation Testbed) test rig at the TU Munich a measurement environment is established using an optical data transmission to extract strain signals from the rotating system. First investigations show the potential of optical strain measurements in the rotating systems for a variety of applications.
Deep Learning Based Framework for Multicopter Sensor Data Imputation
Authors:   Rensselaer Polytechnic Institute, Makkar Gaurav , Gandhi Farhan
Published: June 2023

The study presented in this paper introduces a novel approach for imputing missing sensor data in multicopters, which enables enhanced safety and reliability by leveraging the multitude of sensors on these aerial vehicles. The proposed approach is based on two deep learning techniques, namely Autoencoders (AE) and Long Short-Term Memory (LSTM) networks. The effectiveness of this approach is evaluated using flight test data from a 2.5 kg hexacopter, and three different scenarios of missing data are considered. To validate the performance of the proposed approach, it is compared against two commonly used imputation techniques: k-Nearest Neighbor (KNN) imputation and Random Forest imputation. The results indicate that the proposed approach outperforms both KNN and Random Forest in terms of the accuracy of imputation. The network has an error of less than 10% when processing signals with six missing sensor readings for a duration of 10 seconds. In contrast, KNN and Random Forest algorithms have an average error of 18% and 26%, respectively. Moreover, the trained model can handle missing data with varying degrees of sparsity, which makes it a more robust and flexible solution. The study also investigates the impact of using initial estimates provided by the Kalman Filter for training the deep learning models. It is observed that incorporating these estimates does not result in any improvement in the imputation accuracy. This suggests that the proposed approach is able to learn the underlying patterns in the data without the need for additional information from the Kalman Filter. Overall, the results of this study demonstrate the potential of deep learning techniques for imputing missing sensor data in multicopters. The proposed approach offers a more accurate and efficient solution than the traditional imputation techniques, and can handle varying degrees of data sparsity. The findings of this study have important implications for the design and operation of multicopters, and could result in enhanced performance and operational effectiveness of these aerial vehicles.
A Digital Twin Framework for Structural Health Monitoring Enhanced by Physics-Based Reduced Order Modeling and Stochastic Time Series Models
Authors:   Rensselaer Polytechnic Institute, Zhou Peiyuan , Fan Yiming , Ju Brian , Kopsaftopoulos Fotis
Published: June 2023

In this work, a hybrid digital twin (DT) framework for structural health monitoring (SHM) of rotorcraft structures is proposed. This framework integrates both ultrasonic-guided wave-based and vibration-based SHM schemes for tackling damage detection, identification and quantification under uncertainty. To achieve that, two novel data-driven reduced-order models (ROMs) are introduced to approximate high-frequency (ultrasonic) guided-wave dynamics and low-frequency vibration dynamics, respectively. For the high-frequency DT (HFDT), a novel scheme taking direct guided wave signals as inputs is proposed for damage detection and quantification task. In the training phase, a Convolutional AutoEncoder (CAE) is trained to achieve accurate ultrasonic wave signal reconstruction. In the online monitoring phase, the latent space representations of inputs can be extracted in an automated manner through the encoder. The extracted features are then combined with a feed forward neural network (FFNN) and Gaussian process (GP) models to provide damage level estimates in a deterministic and probabilistic manner, respectively. For the low-frequency DT (LFDT), the cornerstone of the proposed approach is the stochastic functionally pooled (FP) time series family of models. The FP model structure makes use of functional data pooling techniques for combining and optimally treating as one entity the data obtained from various structural states, and statistical techniques for model estimation. Damage detection and quantification are treated as an inverse problem and appropriate optimization techniques. To address the LFDT requirement for training data under various structural states, a Bayesian inversion physics-based finite element model (FEM) framework is postulated that enables the FEM updating and calibration via the use of experimental data. To demonstrate the applicability and evaluation of the proposed DT platform, two case studies are performed: (i) HFDT/ROM of guided-wave in Airbus H125 main rotor blade for SHM purposes and a (ii) LFDT/ROM of an Airbus H125 main rotor blade updated via vibrational data.
Defects Detection in Rotor Composite Parts using AI
Authors:   Airbus Helicopters, Griselin Nicolas , Barbier Pierre
Published: June 2023

During the manufacturing process of rotor composite parts, each part is systematically controlled using a Radiographic Testing (RT) approach. This is a non-destructive testing (NDT) method, which uses x-rays to examine the internal structure of manufactured components identifying any flaws or defects within the material. This paper describes a three steps approach to detect defects in radiographies of composite parts using Artificial Intelligence (Convolutional Neural Network and Computer Vision analysis).
Process of Implementation and Certification of the First Parts Manufactured in Selective Laser Sintering Technology, on the Example of PZL Mielec a A Lockheed Martin Company
Authors:   PZL Mielec a Lockheed Martin Company, Banas Aleksander , Wojtuszewski Radoslaw , Galaczynski Tomasz , Glodzik Marcin
Published: June 2023

The article presents material and functional tests carried out to implement the first part made in the Selective Laser Sintering (SLS) technology on the aircraft. The tests were done based on guidelines from aviation regulations and internal standards of PZL Mielec and Lockheed Martin Company.
Floquet Instability in Periodically Reversing Flows
Authors:   Washington University in St. Louis, Welsh Jake , Peters David
Published: June 2023

Current 3-D finite-state wake models are incapable of simulating a maneuver in which the sign of the free-stream velocity changes direction and the rotor enters its own wake - as might occur in the case of a helicopter which ascends and then descends. It is the purpose of this work to create a 2-D finite-state wake model which is capable of handling changes in free-stream direction as a precursor to development of a 3-D model that can do the same. The 2-D finite-state model used for reentry modifications is an existing model created by Peters, Johnson, and Karunamoorthy. By the addition of a parameter which changes the sign of the free-stream accordingly, a model capable of handling forward and backward flight is developed and tested. Upon testing of the model for an oscillatory free-stream which changes direction, it was discovered that the presence of a singularity causes the system to become unstable. This behavior was determined to be due to a Floquet instability which occurs in periodic free-streams that reverse direction.
Generic Tilt-Rotor Simulation Model with Coupled Flight Dynamics, State-Variable Aeromechanics, and Aeroacoustics
Authors:   University of Maryland, Saetti Umberto , Bugday Batin
Published: June 2023

This paper describes the development, implementation, and validation of a generic tilt-rotor simulation model with coupled flight dynamics, state-variable aeromechanics, and aeroacoustic. A major novelty of this work lies in the integration of the flight dynamics with a state-space free-vortex wake code that adopts a near-wake vortex-lattice model. This way, the flight dynamics are augmented by the vortex wake dynamics so that the coupled flight and wake dynamics is self-contained and inherently linearizable. The model is implemented for a Bell XV-15 tiltrotor and validated against U.S. Army/NASA XV-15 flight-test data and other data in the literature. Flight control design is performed to provide desired stability, performance, handling-quality properties and to allow for a fully-autonomous transition between hover in helicopter mode and high-speed flight in aircraft mode. The simulation model has clear applications in the development and testing of advanced flight control laws, aeromechanics analysis, and in the prediction of aerodynamically-generated noise in generalized maneuvering flight.
Modeling and Flight Dynamics Analysis of Rotor-on-Wing Interference Effects of a Winged Single Main Rotor
Authors:   San Jose State University, Glover Emily ,   US Army CCDC AvMC, Lopez Mark , Padthe Ashwani , Berger Tom
Published: June 2023

The U.S. Army is considering a single main rotor helicopter with a wing for Future Vertical Lift (FVL) Capability Set 1 (CS-1). Previous work has been done to design a blade element flight dynamics model of a generic winged single main rotor helicopter. To increase the fidelity of the model, a rotor-on-wing interference model was developed to determine how the interference impacts trim and flight dynamics of the winged single main rotor configuration throughout the flight envelope. The model leverages preexisting models to determine the rotor wake location and radius as well as the download on the wing at low speeds. Once the wake moves off of the wing, the model applies download observed in CFD, wind tunnel tests, and flight tests to both wings. Finally, differential lift is applied to the wing as the reverse flow region forms. The differences in trim and flight dynamics of the rotor-on-wing interference model compared to the no interference model at different wing locations and lift share ratios are important to understand when designing control systems, power required for trim and dynamic maneuvers, and actuator throw. It was found that the control system designed for the generic winged single main rotor does not need to be adjusted for rotor-on-wing interference. Therefore rotor-on-wing interference models that focus on trim are sufficient.
Enhanced Flight Dynamics Models with Aerodynamic Interference for Real-Time Simulation of VTOL Concept Vehicles
Authors:   Advanced Rotorcraft Technology Inc., Gladfelter Matthew ,   NASA Ames Research Center, Malpica Carlos , He Chengjian , Saberi Hossein , Johnson Wayne , Silva Christopher
Published: June 2023

In an effort to establish common models to support the Advanced Air Mobility (AAM) community, NASA has designed a fleet of VTOL configuration reference models. Advanced Rotorcraft Technologies (ART) in cooperation with the NASA Ames Aeromechanics branch has developed FLIGHTLAB simulation models for several of these AAM VTOL concept vehicles. These simulation models are real-time capable while maintaining accurate flight dynamic characteristics with enhanced interference simulation by extracting important modeling parameters from Viscous Vortex Particle Method (VVPM). The focus of the paper is threefold. First, it introduces the simulation models developed and describes their modeling characteriestics important to control and flight dynamics simulation. Second, the method for deriving the interference coefficients between model components such as rotors and wings is outlined. Implementation of the method for the lift+cruise and tiltwing models are discussed in detail. Third, the accuracy of the interference enhancement is assessed, with emphasis placed on the impacts to trim and flight dynamic characteristics. The interference enhancement method is further used to evaluate configuration design decisions by quantifying performance aspects of interference. This research effort culminated in simulation models for the AAM VTOL concept vehicles, with proper interference and real-time capability.
Autorotation Modeling, Simulation, and Analysis of a Generic Lift-Offset Coaxial Compound Rotorcraft
Authors:   San Jose State University, Padthe Ashwani ,   US Army CCDC AvMC, Lopez Mark , Glover Emily , Berger Tom
Published: June 2023

Lift-offset coaxial compound rotorcraft designs have been proposed for the U.S. Army Future Vertical Lift (FVL) programs. Without a need for the tail rotor and equipped with a pusher-propeller, the coaxial compound configuration is capable of achieving high airspeeds and perform maneuvers not feasible for the conventional rotorcraft. To facilitate an independent assessment of the lift-offset coaxial configuration by the U.S. Army, a physics-based flight dynamic model of a 14,000 lbs gross weight configuration was developed using open source data and implemented into the HeliUM-A comprehensive analysis code. This paper evaluates the coaxial configuration for autorotation performance in case of an engine failure. The HeliUM-A code is enhanced to simulate a steady descending autorotative trim condition with and without the pusher-propller declutched from the main rotor. Minimum descent angle and sink rate occur at approximately 70-80 kts airspeed. The declutched case with pusher-propeller speed reduced by 75% yields the lowest sink rate and descent angle. Flight dynamics responses in steady descending autorotation are analyzed with the yaw rate response showing significant differences compared to a steady level flight condition.
How to Integrate the Management of Operating Procedures and Crew Training into UAS Development
Authors:   Technical University of Munich, Schmiechen Kevin , Hoffelner Julius , Holzapfel Florian
Published: June 2023

Already for the prototyping phase of Unmanned Aircraft System (UAS) development, operating procedures need to be defined and approved by the authorities to conduct flight tests. Especially in this early phase, where the specification and implementation details of the UAS are regularly updated, the operating procedures need to be aligned accordingly. Furthermore, the crew needs to be trained in theoretical and practical courses for these changing procedures to be well prepared for the operation of the aircraft system. In this paper, we show how we integrated the management of operating procedures and crew training into our UAS development process. We describe the development of the procedures and training material, their release management, and the traceability to the related system development artifacts. We also show how we implemented the execution and logging of procedure validation and crew training. Based on automatic reports, we can monitor the validation status as well as the training status of the crew, identify missing validation, and determine when retraining is required. The process and its implementation are demonstrated with exemplary data from our ongoing work.
Development of a Coupled Torsional Dynamics and Gear Contact Model to Predict Peak Loads in a Tiltrotor Drive System
Authors:   Leonardo Helicopters, Albuck Nathaniel , Mathur Tanmay , Haidar Ahmad
Published: June 2023

The tiltrotor drive system is a complex and coupled system with different torsional dynamics compared to conventional rotorcraft. It is designed to guarantee safety and reliability and tested for the effects of its dynamics and loads on component sizing. The epicyclic gearing system, the final reduction stage in most aircraft gearboxes, is most impacted by such dynamics. The components of this subsystem must withstand all peak loads due to novel control strategies and torsional dynamics. In this paper, a gear contact analysis model is coupled with a validated torsional dynamics model of a tiltrotor interconnected drive system. The coupled model predicts component-level design loads in the interconnected drive system originating from its torsional dynamic behavior. An accurate gear macro and micro geometry is generated in the gear contact model which is used to derive the time varying mesh stiffnesses at the sub-component interfaces. The variable mesh stiffnesses are applied in the gear dynamic model to simulate the dynamic responses of the gear system under load. Finally, a dynamic overload factor relating the peak dynamic and static loads is analytically assessed, and it is shown to exceed conventional predictions in the case of an asymmetrically loaded interconnected drive system. This dynamic factor can be implemented to inform design decisions during the development of future multi-rotor VTOL aircrafts to mitigate component damage and, in turn, increase the safety and extend the lifespan of critical components.
Engine Usage Analysis Using Unsupervised Machine Learning
Authors:   Airbus Helicopters, Cerqueira Stephane , Morel Herve
Published: June 2023

During operation, Helicopter Gas Turbine undergo various types of degradation due to high temperatures and mechanical loading. Its life assessment and associated maintenance concepts are oftenly based on counters of type of cycles or running hours. In the present article, a methodology for analyzing engine usage is exposed thanks to big data and subsequent Machine Learning capability. Attention is focused on Flight Code Recognition and its value while having a close look at the damage experienced, in flight, by engines. The specific case of the creep counter is discussed and illustrated through real examples of typical helicopter missions. It allows demonstrating the benefits of such approach while defining the maintenance model or providing recommendations in preventing unexpected engine removal prior to TBO. Finally, the limitations of the present model are listed and a way to formalize an universal model, where the steady and transient phases are treated separately, is presented.
Dynamic Simulation of a Rotorcraft Main Transmission with Continuous Variable Ratio
Authors:   TU Wien, Scheu Thomas , Poks Agnes , Donner Florian , Weigand Michael
Published: June 2023

The 'VARI-SPEED II' project involves TU Munich, TU Wien, Zoerkler Gears, and Advanced Drivetrain Technologies GmbH developing a drivetrain that allows variable speed of a helicopter's main rotor. This is beneficial for different speed requirements, reduced noise, and higher efficiency. Various researchers have investigated the benefits and suitable technologies for varying main rotor speed. Calculation formulas were established to find the ratio distribution of gear stages with the lowest total mass of the drivetrain, and electric variators are potential solutions. The architecture with two compound splits before the bevel gear stage was chosen for the dynamic simulation of the drivetrain due to its favorable design considerations. In the 'VARI-SPEED II' project, control of the variable speed drivetrain is crucial for achieving the desired variable main rotor speed. To achieve optimal control, a fuzzy model predictive control (FMPC) approach has been proposed. The FMPC has several advantages, including the ability to handle nonlinearities and uncertainties. Furthermore, the FMPC is real-time capital and of and can adapt to changing operating conditions.
Full Scale Gear Tooth Bending Fatigue Tests Obtained Early in the Development of a Rotorcraft Transmission
Authors:   Sikorsky a Lockheed Martin Company, Gmirya Yuriy , Palcic Peter , Binney Dave , Hu Wei , Carter Erin
Published: June 2023

A new gear testing method is introduced to reduce development cost and time. It allows component-level testing of individual gear meshes and new gear designs. Instrumented gear sets are tested at full load while the rest of gearbox components are still being built. Since the fatigue strength of the gears is determined earlier in the development cycle, design deficiencies are identified and understood earlier. In this new method, an individual gear mesh installed in a stiff facility housing is used to mimic the contact pattern and bending stress demonstrated by the same mesh in an actual aircraft housing. Analytical gear models are used to identify the displacement difference between the stiff test facility and the aircraft housing. The test stand is designed so it can be adjusted accurately to provide gear and pinion positions that are representative of the deflected positions under load in the aircraft housing. A spiral bevel mesh and a split torque double helical reduction stage with multiple meshes are evaluated using the developed method. The contact pattern and strain survey results of the gear meshes are correlated with predicted results.
ANTROPOCENE, EVOLUZIONE DELLA CONOSCENZA E TEORIA DELLA POLITICA INTERNAZIONALE
Authors: Montani Guido
Published: June 2023

Il trattato di Jürgen Renn sull'evoluzione della conoscenza presenta una sintesi di numerosi studi sul contesto storico-sociale del concetto di "rivoluzione scientifica", proposto da Kuhn (1962). Una rivoluzione scientifica è il momento culminante di una fase di incubazione ed è seguita da una fase di istituzionalizzazione. Questo saggio discute alcuni concetti (civiltà e Stato, nazionalismo e sovranità, Stato e rivoluzione, Antropocene e cosmopo-litanismo) necessari allo scienziato sociale per affrontare le sfide contemporanee dell'Antropocene.
UNITED STATES, BRAZIL, POLITICAL POLARIZATION AND DEMOCRATIC PUSHBACK. ASSAULT ON DEMOCRACY?
Authors: Ferraris Nicolò
Published: June 2023

This article, starting with the attacks on U.S. and Brazilian democratic institutions in January 2021 and 2023, aims to understand whether and how the phenomenon of political polarization may be related to an increase in political violence in democracies and a possible democratic retreat. Likewise, the concept of democratic resilience and how democracies can resist the dangers of political polarization will be investigated. The phenomenon of political polarization can be detrimental to democracies in that, if extreme, it can bring politics to the essential categories of "friend and foe," the politics of "us versus them," which can result in the acceptance of undemocratic actions such as the aforementioned assaults on institutions. However, democracies can find in the consolidation of civic and democratic culture, and strict separation of powers, the means to resist challenges to democracy itself, including the phenomenon of political polarization.
EVOLUTION OF THE CIVIL-MILITARY RELATIONSHIP IN PAKISTAN IN THE POST-COVID ERA
Authors: Abenante Diego
Published: June 2023

Pakistan has been ruled by military regimes for almost half of its history. Since the first coup in 1958, the military has experimented with a variety of political strategies and models of civil-military relations, including purely military rule and various forms of hybrid regimes. The military's attitude toward Islam has also evolved over time. Since 1947, the military has recognized the role of religion as the basis of national identity and has sought to integrate it into official propaganda despite the diversity of conceptions. The nature of the relationship between political parties and the military underlies recent political evolution. The 2018 general elections saw Imran Khan's Pakistan Tehrik-e-Insaaf (PTI) prevail in large part due to the support it received from the military establishment. The military chose to support PTI as an alternative to the two main national parties, the Pakistan Muslim League-N (PML-N) and the Pakistan People's Party (PPP), with which the military has been at odds for nearly two decades. However, the 2018 elections showed that the military's ability to control the political scene is limited. Indeed, the PML-N and PPP have maintained their traditional strongholds in Punjab and Sind. Despite the support of the military, the PTI only managed to prevail in the elections with a slight majority. The crisis of Imran Khan's government between 2020 and 2022 was due to three main factors: divisions between the parties in the ruling coalition; mismanagement of the emergency caused by the Covid-19 pandemic; and the PTI and military's differing view of economic cooperation with Beijing and particularly the China-Pakistan Economic Corridor. This situation led to a conflict between PTI and the military and the no-confidence vote in parliament in April 2022 that ousted Imran Khan from power.
IL DISAGIO LIBERALE DI FRONTE AL NUDGING
Authors: Carter Ian
Published: June 2023

Molti liberali si sono opposti alle politiche pubbliche di nudging. Tuttavia, hanno trovato difficile individuare la vera fonte del loro disagio nei confronti di tali politiche. In questa sede si sostiene che la fonte del disagio dei liberali nei confronti del nudging non risiede nel loro attaccamento alla libertà o all'autonomia (che il nudging non mette ovviamente in discussione), ma nel loro attaccamento all'uguaglianza morale di base. L'affermazione dell'uguaglianza morale di base da parte dei liberali dipende dall'approvazione, a un livello ancora più elementare, di un tipo di rispetto per le persone che esclude la valutazione di alcune capacità agenziali di base delle persone. Il nudging, invece, è motivato proprio da questo tipo di valutazione. Questa fonte di disagio è più profonda e preoccupante dell'attaccamento ai diritti di libertà individuale. I sostenitori del nudging negano di fatto una parte essenziale della base normativa degli stessi diritti di libertà che si suppone vogliano rispettare.
La conquista dei diritti. Un’idea della storia
Authors: Felice Emanuele
Published: June 2023

Non disponibile.
Hayek: A Life, 1899-1950
Authors: Caldwell Bruce , Klausinger Hansjoerg
Published: June 2023

Non disponibile.
Amicus Lucretius. Gassendi, il De rerum natura e l’edonismo cristiano
Authors: Piergiacomi Enrico
Published: June 2023

Non disponibile.
Costituzionalismo ambientale. Atlante giuridico per l’Antropocene
Authors: Amirante Domenico
Published: June 2023

Non disponibile.
Teaching religion as change for social transformation in contemporary African and non-African universities: a South African manifesto
Authors: Simut Corneliu C.
Published: June 2023

This article is a research report on the international colloquium entitled ‘Re-Imagining Curricula for a Just University in a Vibrant Democracy’, hosted by the University of Pretoria in 2017 to address a series of prospective changes in religious studies curricula in African and non-African universities. Anchored in the principles of the Draft Framework Document, a South African manifesto authored by a team of specialists from the University of Pretoria advocating educational reform in the field of religion, the colloquium debated the necessity of curricular change from the perspective of ecodomy, seen as a constructive attempt to modify university curricula to include relevant approaches to religion. Consequently, the discussions revolved around the idea of ‘ecodomical change’ as a socially transformative step towards achieving community development in tertiary education religious institutions.Contribution: This article, however, focused on the Draft Framework Document and its distinctive contribution to the pedagogy of theology and religious studies within the University of Pretoria.
G9a-targeted chaetocin induces pyroptosis of gastric cancer cells
Authors: Huang Mian-Qing , Tao Gui-Lan , Han Li-Fang , Tian Shu-Hong , Zhou Peng
Published: June 2023

Objective:

To evaluate the effect of chaetocin on pyroptosis of gastric cancer cells and its underlying mechanisms.

Methods:

The proliferation of gastric cancer cells was detected by trypan blue staining. Flow cytometry and Hoechst/propidium iodide double staining were used to detect apoptosis and pyroptosis. Cellular ultrastructure was observed by transmission electron microscopy. The levels of p-mixed lineage kinase domain-like (MLKL), gasdermin-D (GSDMD), gasdermin E (GSDME), N-GSDMD, and N-GSDME proteins were detected by Western blotting. In addition, lactate dehydrogenase (LDH) release assay was used to verify pyroptosis induced by chaetocin, and caspase 3 inhibition test and siRNA interference test were conducted to investigate pyroptosis mechanisms.

Results:

Chaetocin at concentrations of 200 nmol/L to 600 nmol/L inhibited the proliferation of AGS, HGC27, MKN28, and SGC7901 gastric cancer cells in a dose-dependent and time-dependent manner by inducing apoptosis and pyroptosis. Significant ultrastructure changes, such as chromatin condensation, vacuolization, disrupted mitochondrial cristae, and increased nuclear occupancy, were observed after treatment with chaetocin in SGC7901 cells. Chaetocin at a concentration of 400 nmol/L significantly increased the number of pyroptotic cells, LDH release, and the ratio of N-GSDME/ GSDME (P<0.01), which were reversed by Z-DEVD-FMK. In addition, chaetocin did not affect the expression of GSDMD. G9a silencing abolished the effect of chaetocin on the expression levels of GSDME and N-GSDME and LDH release (P>0.05).

Conclusions:

In addition to inducing apoptosis, chaetocin inhibits gastric cancer cells by inducing pyroptosis via the caspase 3/GSDME pathway. G9a was the target of chaetocin to induce pyroptosis of gastric cancer cells.
A Prospective Clinical Study Evaluating the Effectiveness of Jatipatri Ksheerapaka in Anidra (Primary Insomnia)
Authors: Kumar Saranya S , Shetty Suhas Kumar , Mohan Rijin
Published: June 2023

Introduction:

Sleep is one of the most inevitable components in one's life. Good quality sleep is a basic human need and is essential for good health, good quality of life, and performing well during the day. Anidra is one among the Vataja Nanatmaja Vikaras where quantity of Nidra is reduced.

Objectives:

The objective was to study the effectiveness of Jatipatri Ksheerapaka (medicated milk preparation with aril of Myristica fragrans) in primary insomnia.

Materials and Methods:

A clinical trial to assess the effectiveness of medicated milk preparation with aril of Myristica fragrans in managing Anidra. An open-labeled single-arm uncontrolled exploratory clinical trial was conducted at the outpatient and inpatient department level at an Ayurveda teaching hospital, Karnataka. Thirty-two patients fulfilling the inclusion criteria were selected by convenient sampling method. They were administered with Jatipatri Ksheerapaka 30 ml, once in a day at bedtime after food for 30 days. The effect of therapy was assessed with Insomnia Severity Index Scale before and after treatment and 30-day follow-up.

Results and Discussion:

All symptoms showed statistical significance after 30 days of treatment and during follow-up. Jatipatri Ksheerapaka is vatapittahara by its property. Anidra is a condition caused predominantly due to Vata Prakopa and deranged rajas and tamas. Jatipatri Ksheerapaka worked upon stabilizing vata and balancing rajas and tamas.

Conclusion:

Jatipatri Ksheerapaka 30 ml orally for a duration of 30 days was found effective clinically and statistically in managing the clinical symptoms of Anidra (primary insomnia) with P < 0.05.
Maximal operators on BMO and slices
Authors: Shaabani Shahaboddin
Published: June 2023

We prove that the uncentered Hardy–Littlewood maximal operator is discontinuous on
${BMO}(\mathbb {R}^n)$
and maps
${VMO}(\mathbb {R}^n)$
to itself. A counterexample to the boundedness of the strong and directional maximal operators on
${BMO}(\mathbb {R}^n)$
is given, and properties of slices of
${BMO}(\mathbb {R}^n)$
functions are discussed.
Prevalence and Predictors of COVID-19 Long-Term Symptoms: A Cohort Study from the Amazon Basin
Authors: Silva Kletey M. , Freitas Dhayn C. A. , Medeiros Sabrina S. , Miranda Laís V. A. , Carmo Jessica B. M. , Silva Roberta G. , Becker Luana L. , Abreu Emanuel S. , Buranello Leonardo , Souza Maria S. M. , Nadruz Wilson , Fernandes-Silva Miguel M. , Maguire James H. , Toledo-Cornell Cristina , Silvestre Odilson M.
Published: June 2023

It remains unclear whether a previous history of tropical infectious diseases and a second SARS-COV-2 infection may influence the likelihood of later symptoms. In this prospective cohort study, individuals infected with SARS-CoV-2 were followed up by telephone shortly after diagnosis of COVID-19 and again 12 months later. Poisson regression was used to identify the predictors of the highest number of symptoms in the post-COVID-19 syndrome. A total of 1,371 patients with COVID-19, with a mean age of 39.7 ± 11.7 years and 50% female, were followed for 12 months. Reinfection was found in 32 (2.3%) participants, and 806 (58.8%) individuals reported a previous history of dengue, malaria, Zika, chikungunya, leprosy, and visceral leishmaniasis. Eight hundred seventy-seven (63.9%) participants reported late symptoms related to COVID-19. After adjusting for multiple factors, female sex, non-White race, number of acute-phase symptoms, body mass index, and reinfection were independent predictors of higher number of symptoms in post-COVID-19 syndrome. Female sex, non-White race, number of acute-phase symptoms, body mass index, and reinfection, but not previous endemic tropical diseases, were associated with long-term symptoms.
Leveraging Historical Thermal Wind Tunnel Data for ML-Based Predictions of Component Temperatures for a New Vehicle Project
Authors: Freytag Lukas , Enke Wolfram , Rottengruber Hermann
Published: June 2023

The thermal operational safety (TOS) of a vehicle ensures that no component exceeds its critical temperature during vehicle operation. To enhance the current TOS validation process, a data-driven approach is proposed to predict maximum component temperatures of a new vehicle project by leveraging the historical thermal wind tunnel data from previous vehicle projects. The approach intends to support engineers with temperature predictions in the early phase and reduce the number of wind tunnel tests in the late phase of the TOS validation process. In the early phase, all measurements of the new vehicle project are predicted. In the late phase, a percentage of measurements with the test vehicle used for the model training and the remaining tests are predicted with the trained ML model. In a first step, data from all wind tunnel tests is extracted into a joint dataset together with metadata about the vehicle and the executed load case. With the extracted dataset, different Machine Learning (ML) models are trained and optimized to predict maximum component temperatures. The ML-based temperature prediction is evaluated by two vehicles with different vehicle platforms. Temperature predictions are made for engine and suspension bearings. The predictions in the early phase show very good results with a maximum mean absolute error (MAE) between 3 and 5 °C for the first vehicle. The evaluation of the second vehicle results in higher MAEs between 3 and 8 °C. In the late phase, the MAEs lie between 2 and 4 °C for the suspension bearings of both vehicles using 20 % of the wind tunnel tests. Despite the promising results, the ML models need to be further improved and tested to use them as an accurate and reliable predictor in the current TOS validation.