bluuebunny/crossref_metadata_2025 huggingface dataset:
Ostrogoths in Slovenia? Case study of a Late Antique cemetery in Miren, western Slovenia
Authors: Tratnik Vesna , Karo Špela
Published: July 2023

The archaeological investigations conducted between 2009 and 2013 at Japnišče, a site in Miren, unearthed part of a cemetery from the late 5th and early 6th century. It is a small cemetery located at a formerly major road that connected Aquileia and Emona. Nine burials have thus far been investigated, though the scattered finds of human bones in the mixed layers and fills of pits suggest the burial ground was originally larger. A particular feature of the cemetery is the East Germanic elements visible in the costume and the artificially deformed skulls. We argue that these elements indicate the presence of a Germanic population, with historical sources pointing to the Ostrogoths as the most likely people. The interpretation of the Miren cemetery relies on a meticulous typo-chronological analysis of the recovered grave goods, as well as a study of objects from the late 4th and early 5th centuries that originated from the Lower Danube Basin, and the study of East Germanic elements from the late 5th and the initial decades of the 6th century unearthed at sites in Slovenia. Finally, the site is compared with similar cemeteries in Italy and Austria.
Stratigrafsko najstarejši zgodnjesrednjeveški grobovi in začetek pokopavanja na grobišču Župna cerkev v Kranju
Authors: Rihter Jernej
Published: July 2023

Članek se ukvarja z analizo grobov, izkopanih pri Župni cerkvi v Kranju, ki so bili na podlagi dosedanjih raziskav opredeljeni kot najstarejši na tem grobišču. Za takšne so bili do zdaj opredeljeni grobovi (večinoma) brez pridatkov, ki so bili globoko vkopani v prostorne in med seboj pravilno razmeščene grobne jame, obložene s kamni oz. lesom in orientirane proti vzhodu. Posamezne skupine takšnih grobov, izkopanih do leta 1984, so bile na podlagi arheoloških primerjav datirane v konec 7. in v 8. st.

Analiza stratigrafije grobov celotnega grobišča, v katero smo vključili tudi ugotovitve poznejših izkopavanj in pregled zgodovine raziskav, pokažejo, da pri grobovih, do zdaj opredeljenih kot najstarejših, ni šlo vselej za stratigrafsko najstarejše grobove in da so bile med nekaterimi tudi superpozicije.

V prispevku skušamo ugotoviti čas začetka pokopavanja na podlagi starih in novih kronoloških podatkov (relativna kronologija grobov in tipokronologija). Za izbrane stratigrafsko najstarejše grobove na tem grobišču prvič prinašamo radiokarbonske datacije (14C), ki smo jih časovno zožili z datacijami stratigrafsko mlajših grobov s predmeti. Obravnavani grobovi se po gradnji groba ločijo na dve skupini. Pokopavanje se je začelo najverjetneje v 8. st., pred letom 774/775 (14C) s prvo skupino, z možnim trajanjem vse do začetka pokopavanja druge skupine. Druga skupina grobov ni starejša od leta 774 in se je začela že pred začetkom 9. st. ali najpozneje takrat.
13 de octubre de 2013: Firma del Convenio Minamata sobre el mercurio – Análisis desde la realidad de los pequeños mineros artesanales de oro de Madre de Dios, en Perú
Authors: Baudin Carole
Published: July 2023

Se festejará este año el décimo aniversario de la firma del Convenio Minamata sobre el uso del mercurio. Este acuerdo firmado por 128 países, al buscar proteger la salud humana, la preservación del medioambiente y de la biodiversidad se enfoca sobre la regulación de esta substancia en la minería de oro artesanal a pequeña escala, identificada como la principal responsable del uso y contaminación del medioambiente en el mundo. Es la ocasión aquí para analizar como esta política internacional se tradujo en la actividad real de las comunidades mineras de la región amazónica de Madre de Dios en Perú con las cuales se trabajó en el Proyecto Wanamei. Al describir las incidencias de tal acuerdo sobre la vida y el trabajo de estas comunidades, buscaremos debatir dos ejes de reflexión: 1) la necesidad de repensar las dimensiones territoriales y temporales de tales acciones publicas 2) la necesidad de cambiar el enfoque de las racionalidades de acción subyacentes desde una lógica unicéntrica hacia una filosofía pluricéntrica, valorizando las prácticas y saberes locales con fines de alcanzar soluciones sostenibles.
Les effets des moulins à eau sur la température des cours d'eau : l'exemple du moulin de Thévalles
Authors: Donati Francesco , Touchart Laurent , Bartout Pascal , Choffel Quentin , Cor François Le , Carceles Célia , Cairault Alban
Published: July 2023

Au cours des dernières années, en France, les moulins à eau ont été redécouverts grâce à leur potentiel hydroélectrique. Leur fonctionnement dépend d'une retenue de seuil, dont la nature peut être assimilée à celle d'un étang au cours de certaines périodes de l'année, notamment pendant l'été, quand les débits sont moins forts et que la colonne d'eau présente une stratification thermique. Aussi l'objectif de cet article est-il d'étudier si, à l'aval de ce type de milieu, les mêmes effets thermiques que ceux des petits plans d'eau se font ressentir, comme les réchauffements estivaux ou la réduction des amplitudes thermiques. Pour cela, des thermomètres enregistreurs ont été placés à l'amont, à l'aval et au sein de la retenue de seuil du moulin de Thévalles (Mayenne), toujours en fonctionnement. Les résultats obtenus montrent des effets sur la température de l'eau plutôt faibles (en moyenne quelques dixièmes de degré), à la fois quand la roue hydraulique est active et quand elle ne l'est pas, c'est-à-dire quand les seules surverses fonctionnent.
Parent and Child Perspectives of Literacy Instruction During Emergency Remote Learning
Authors: Eutsler Lauren , Brom Krystle , Kinard Widad
Published: July 2023

The purpose of this empirical book chapter is to better understand the influence of remote learning during the COVID-19 pandemic, with an emphasis on literacy instruction. This nationwide case study, conducted in summer and fall 2020, utilized individual video interviews to gather perspectives from 18 elementary parents and 25 elementary-aged children from 14 different states in the United States. Results describe the following themes in detail: (1) changes in the home, (2) changes in literacy instruction, (3) children missed social interactions, and (4) suggestions to improve online learning. The field of education can benefit from vivid accounts of these experiences to improve future literacy instruction, especially when using digital technologies and tools.
Teaching by Example and Learning by Doing
Authors: Hickey Sean
Published: July 2023

At the beginning of the COVID-19 pandemic, much of the world entered lockdown and schools shifted to emergency remote teaching. Despite educational researchers having long identified online teaching skills as necessary for teacher training, teachers were largely untrained and generally ill-equipped to teach online. Teacher-preparation programs are still lacking an emphasis in developing digital competencies, instead of focusing on the in-person, face-to-face teaching experience. This chapter is a case study of an undergraduate class specifically designed to help teachers learn skills and competencies related to online teaching and learning. The course addresses the online-teaching digital-skills gap with a two-pronged approach: (1) First, the design of the class follows proven, evidence-based practices for online instruction; and (2) second, each assignment of the course provides opportunities for students to develop technical skills through hands-on work, culminating in a digital storytelling project that puts all the skills to use.
Digital Skills of Teachers
Authors: Yadav Seema
Published: July 2023

The digital age of the twenty-first century requires the use of information and communication technology (ICT). The development of the digital world is opening up a wide range of new possibilities for sharing and collaboration across numerous industries. Digital competence is one of the crucial skills that instructional staff members must possess. The necessity for the adequate acquisition of novel information capabilities in the information society has been one of the key forces behind curriculum change. Although digital technologies are increasingly being used in education, it's important to understand how they might be used to progress educational reform and enhance effective pedagogical techniques. Teachers should be mindful that technology will affect the teaching strategies they employ. The transfer of 21st-century core competencies requires that instructors exhibit digital proficiency. The development of digital teaching abilities is a challenge for teacher education needs to be a priority for the education institutes should be a priority in education public policy.
A Bivariate Analysis of Teachers' Well-Being and Personal Values for Inclusive Education
Authors: Ianniello Annalisa , Alodat Ali Musleh , Corona Felice
Published: July 2023

This study examines the relationship between value priorities and hedonistic (emotional balance and life satisfaction) and eudaimonia (psychological and social well-being) aspects of the well-being of support teachers. The sample size includes a group of 402 participants (=43 male/=359 female). The portrait value questionnaire (PVQ-RR) was administered to investigate teachers' values. At the same time, the following scales were used to measure the levels of well-being: positive and negative affect scale (PANAS), satisfaction with life scale (SWLS), psychological well-being scales (PWBS), and social well-being scale (SWBS). A bivariate statistical analysis was performed to detect the correlation between the two variables examined statistically. The results of the correlation analysis show that the values are predictive variables of well-being, more helpful in predicting eudemonic well-being than the hedonic well-being of teachers. This research suggests considering values and well-being within teacher training programs to improve the implementation of inclusive education policies.
Review on Smart Sewage Cleaning UAV Assistance for Sustainable Development
Authors: Pandey Binay Kumar , Pandey Digvijay , Dadheech Pankaj , Mahajan Darshan A. , George A. Shaji , Hameed A. Shahul
Published: July 2023

Autonomous systems that cannot adapt to real-world environments have proliferated due to rapid technological improvement. These programmes will free people from repetitive, inefficient chores. The monotonous, dusty, and dangerous conditions of the unmanned aerial vehicle (UAV) pose a severe threat to human health and safety. Autonomous systems improve supply chain, tracking, and hazardous climate control. This chapter proposes merging compression and track architecture to improve UAV performance. The UAV and pipe increase trackwheel friction. The UAV doesn't move in the tube. Cleaning commences when sensors detect the mouth. Dirt sensors prevent the washing process from working. This chapter focuses on drain cleaning automation. Device automation addresses mobility and space. This study supports this method for garbage disposal and filtering. The technology removes manual cleaning and relies on human control of system movement.
Biomedical Waste Handling Method Using Artificial Intelligence Techniques
Authors: Sengeni D. , Padmapriya G. , Imambi S. Sagar , Suganthi D. , Suri Ashish , Boopathi S.
Published: July 2023

The handling of genetic residues, biohazardous waste, and other non-shrinkable materials such as e-waste is essential for the preservation of Mother Nature and human wellbeing. This chapter will bring forth different methods of managing biomedical wastes, inspecting the roots of the spread of the hazardous virus, and protecting the front-line warriors. To properly react to this disaster, each administration must create a backup strategy based on regional circumstances and the seriousness of the coronavirus's spread. Technology is being used to reduce the need for in-person medical appointments and save on the cost of treatment, which is a boon for human civilization in the context of the pandemic. The Central Pollution Control Board's existing rules provide a framework for managing healthcare waste with respect for the safety of the public. Bio-waste management strategies using IoT and IoMT techniques are illustrated in this chapter.
Understanding Urban Planning Outcomes in the UK
Authors: Mazumdar Suvodeep , Qi Jie , Thakker Dhavalkumar , Goodchild Barry
Published: July 2023

The planning process in the UK is a highly complex system, developed over many decades, and is in the process of rapid transitions into digital planning. Among these transformations is a desire to move from an outputs-based assessment to an outcomes-based assessment process. This is challenging, and in this paper, the authors explore the variety of factors that make outcomes assessment challenging. The authors first studied the literature to understand how outcomes are complex, ranging across different sectors and practices, identifying 359 indicators related to outcomes. The authors then conducted a knowledge mapping exercise to understand the characteristics of the indicators in multiple themes. The authors also invited practitioners for an interview on their perspectives of outcomes assessment, definitions of outcomes, barriers to outcomes, the benefits of outcomes assessment, and how practitioners envision a world with outcomes assessment. The authors conclude the paper with future directions of research.
Using Eye Tracking to Measure Overall Usability of Online Grocery Shopping Websites
Authors: Naeini Ali Bonyadi , Mahdipour Ali Golbazi , Dorri Rasam
Published: July 2023

This article examines usability evaluation methodologies, then presents a non-conscious behavioral indicator based on user eye movements and pupil dilation. The authors test how gender and online buying history affect the behavioral index's usability scores. This study uses three Iranian online food retailers. Thirty participants were asked to add things from predetermined grocery stores to virtual shopping carts before the experiment took them to the other two websites in a random order to collect eye movement data. Each group's presentation order was randomized. The number of fixations, number of saccades, total duration of fixations, scan-path length, pupil size, and task time were inversely linked with self-report usability measures. This research evaluates groups with different levels of online shopping expertise and gender based on experienced usability. Differences between groups suggest that user demographics affect usability.
An Empirical Study on the Application of Blockchain Technology in E-Agriculture
Authors: Wu Chia-Huei
Published: July 2023

At present, the application of blockchain is still at the level of private chain, lacking of systematicness and comprehensiveness, neglecting the participation process of multi-agent stakeholders, and the overall application system is not clear. This paper aims at applying the blockchain technology to the field of e-agriculture, building the hierarchical theoretical framework of e-agriculture, and revealing the impact of blockchain on e-agriculture. Through dividing the hierarchy, this paper finally structures an innovative service UIS application system for e-agriculture using blockchain technology. The main conclusions are as follows: (1) the first step is to solve social problems; (2) economic tasks are influenced by social problems and focus on smart contracts; (3) sustainable improvement of environmental problems requires a balance between economic and social dimensions; (4) application system is constructed at the three levels of unity, information, and supply chain.
Constructal Theory Applied to the Growth of Injection Channels in a Liquid Resin Infusion Problem
Authors: Magalhães Glauciléia Maria Cardoso , Chiomento Marcello Lovison , Isoldi Liércio André , Souza Jeferson Avila , dos Santos Elizaldo Domingues
Published: July 2023

The present numerical study proposes the application of the constructal theory for the build of empty channels inserted in a porous domain, representing the liquid resin infusion process. Two different strategies are employed: 1) I-shaped pre-defined configuration for the empty channel, 2) constructive technique (evolutionary) where the empty channel is built from an elemental configuration and using the performance indicator to define the new position of each empty channel element. It is investigated the influence of geometry over the impregnation time and the amount of wasted mass of resin during the process. The same fluid dynamic conditions and the maximum occupation area of the empty channel were defined for the different strategies. The finite volume method (FVM) and volume of fluid (VOF) were used for the solution of mass, momentum, and transport of resin equations, which model the flow of resin/air mixture. Darcy’s law is applied to represent the porous medium resistance. Results showed that the constructive technique was highly promising in the proposition of configurations that reduced the time of impregnation of resin in the porous medium. Moreover, it was observed that, for the present fluid dynamic conditions, giving more freedom for the formation of empty channels shape also led to a reduction of filling time of resin impregnation in the porous mold.
Development of a Computational Model for the Simulation of an Oscillating Water Column Wave Energy Converter Considering a Savonius Turbine
Authors: Santos Andrei Luís Garcia , Petry Adriane Prisco , Isoldi Liércio André , Dias Gustavo da Cunha , Souza Jeferson Avila , dos Santos Elizaldo Domingues
Published: July 2023

This work presents the development of a computational model for the simulation of an Oscillating Water Column device that converts wave flow into electrical energy. The device is placed into a wave channel and a Savonius turbine is inserted in the inlet/outlet duct of the converter. The modeling of the turbine is performed with a rotational moving mesh that simulates the turbine movement in stabilized operating conditions. This coupling provides the minimization of simplifying assumptions, addressing in a single problem the two phenomena inherent to the device approach: the two-phase, incompressible and turbulent flow of air and water in a wave channel containing the oscillating water column device and the incompressible and turbulent airflow passing through a rotational turbine. The computational model was verified/validated for a free stream turbulent flow over a Savonius turbine and verified for the case of wave flow over a converter without the inserted turbine. Results showed that the coupled model allowed obtaining not only available power but also mechanical power in the turbine. For the rotation imposed in the domain, the turbine did not affect the behavior of the wave flow that impinges on the chamber of the OWC device. An augmentation of the power coefficient of the turbine in comparison with turbines subjected to free stream flows was obtained, showing that the fairing of turbine can led to increased power takeoff.
Modeling and Thermal Simulation of 2U-Rack Servers Applying Computational Fluid Dynamics Techniques
Authors: Chacón Andrés Mauricio Nieves , Oliveira Francisco Bruno Souza , Dominguez Dany Sanchez
Published: July 2023

The data center industry consumes between 196 and 400 terawatt-hours annually, between 1% and 2% of the world's energy consumption. A high percentage of data center energy consumption is associated with air conditioning and cooling systems. The optimization of the data center cooling process can occur at multiple scales, being one of the most relevant to the generation and heat transfer processes within servers. In this approach, we must study the temperature fields of each server’s components and understand airflow behavior within the server chassis. The present work, in its first stage, performs a thermal and cooling analysis for a two-unit rack server (2U-Rack) using computational fluid dynamics (CFD) techniques via Ansys Fluent code. A geometric server model was developed, considering heat generation in the main electrical components and heat and air mass transfer with the data center. The model was validated by comparing simulation results with the server's sensor values and the results of thermography testing. Following CFD simulation, airflow velocity fields, temperature contours, and sensitivity scenarios were obtained, with the goal of proposing an optimization model that would allow us to improve server heat transfer processes in the following steps.
Simulation of a Prototype of Individual Portable Air Purifier
Authors: Guiot Lucas Ló , Zinani Flavia Schwarz Franceschini , Wander Paulo Roberto
Published: July 2023

Covid-19 is a highly contagious aero-transmissible virus. Even after two years of its emergence, new strains appear that require strengthening security measures such as social distancing, the use of masks, etc. It is crucial to prevent contamination, and care for the sanity of the air in closed environments, occupied by two or more people. Aerosols expelled by contaminated individuals dissolve in environments and can contaminate individuals regardless of their location. In this project, an air purifier for individual use was proposed to mitigate the risk of contamination by Covid-19 in closed environments. The equipment has been developed and prototyped, but has yet to be presented in the scope of this article. In this phase of the project, a study was conducted through numerical simulation to understand the effect of using this purifier on air circulation and its scope in the environment. Nine scenarios were developed: five two-dimensional and four three-dimensional, subject to different conditions: (i) closed environment, (ii) air infiltration through doors and windows, (iii) air-conditioner use, and purifier use. In individual use of the purifier, even if it is approximately 50 cm from the person in the room, the curtain of “clean air” coming from the purifier has become ineffective due to the existence of another, more intense outlet. The scenario with the airflow from the air-conditioner showed that the higher intensity of the airflow compared to the prototype purifier's airflow, meant that the prototype's airflow could not protect the user from the theoretically contaminated air mixed in the room. When the simulation of the use of the purifier was not done together with the air-conditioner runoff, the purifier proved effective in providing clean air and "protecting" the user with a wind curtain. However, even when the purified air cannot directly protect the user, the effects of the purifier can be beneficial by reducing the contamination of the air in the room as a whole (with a flow rate of 0.016 m3/s or 57.6 m3/h), and potentially reducing the chances of virus infection.
Numerical Study of the Influence of the Geometric Parameters of a Radial Crystalizer Using a Multiscale CFD Model
Authors: Rodrigues Gustavo Villela , da Rosa Cezar Augusto
Published: July 2023

This work investigates how the configuration of the geometric parameters of a radial crystallizer influences the results of the crystallization of lovastatin by antisolvent and using a multi-scale computational fluid dynamics (CFD) model. The OPENFOAM open-source software uses macro and micromixing expressions for flow, and complete energy and population equilibrium equations during nucleation and crystal growth. The model is based on the Reynolds-Averaged-Navier-Stokes (RANS) equation, along with a multi-environment probability density function (PDF) model and the spatially semi-discretized population equilibrium equation, operating a high-resolution finite volume method. The variation crystallizer construction parameters provided another crystallizer design, and analyses demonstrated improved performance and effects on crystal distribution.
Investigation of Numerical Irregular Wave Generation Using Transient Discrete Data as Boundary Conditions of Prescribed Velocity
Authors: Maciel Rafael Pereira , Machado Bianca Neves , Oleinik Phelype Haron , dos Santos Elizaldo Domingues , Gomes Mateus das Neves , Isoldi Liércio André
Published: July 2023

This work presents a two-dimensional numerical analysis of a wave channel. The goal is to investigate a methodology that uses transient velocity data as means to impose velocity boundary condition for generating numerical waves. To do so, a numerical wave channel was simulated using irregular waves. These waves were obtained using the WaveMIMO methodology, which converts sea data from a spectral model into time series of free surface elevation, and then converts this elevation into transient discrete wave velocity data. For the numerical analysis, computational fluid dynamics ANSYS Fluent software was employed, which is based on the finite volume method. The computational domain and mesh were generated using GMSH software, and the nonlinear multiphase model volume of fluid (VOF) was applied to tackle water-air interaction. In general, the results obtained through the use of discrete data as velocity boundary condition presented a good agreement with free surface elevation converted from the spectral model, and the tests performed provided further insight into the parameters which affect this methodology. Since many studies use regular waves, the proposed investigation stands out for its capacity to improve the use of realistic sea state data in numerical simulations of wave energy converters.
Analysis of Different Multiobjective Optimization Scenarios in Estimating the Adjustable Parameters of a Generalized Cubic Equation of State
Authors: da Silva Géssica Ramos , Torres Maicon de Paiva , Galo Tânia Maria , Soares Junior Acir Moreno , de Oliveira Luiz Nélio Henderson Guedes
Published: July 2023

Since the emergence of the van der Waals model, a lot of equations of state have been proposed to represent the pressure-volume-temperature (PVT) behavior of pure compounds, as is the case with GEOS3C, which is a form of generalized cubic equation of state that uses a temperature function dependent on three adjustable parameters. As the predictive capacity of an equation of state is directly related to the use of adequate and efficient methods for estimating the model's parameters, it is advised to use the multiobjective optimization in this class of problems, due to the conflicting nature of the objective functions. In this context, a MOPSO algorithm, based on the Pareto dominance principle, is used to estimate the parameters of the GEOS3C, through the minimization of the deviations in the prediction of different thermodynamic properties: saturation pressure, saturated liquid volume, enthalpy of vaporization and isobaric heat capacity, in order to assess whether it is possible to obtain a model parameterization that is adequate to represent the different properties simultaneously. Comparisons with experimental data available in the literature are performed showing that multiobjective optimization offers new perspectives for improvements in the parameters estimation of equations of state compared to traditional methods.
Innolot: International Manufacturing Technology Development in Poland
Authors:   Sikorsky a Lockheed Martin Co., C. William
Published: July 2023

The Innolot program represented some firsts for Sikorsky Aircraft and its Polish subsidiary, PZL Mielec. It was the first win of an international research and development program for Sikorsky as well as the largest manufacturing technology investment by either company. The conditions surrounding the program were also somewhat unique. The technologies and innovations developed existed in the United States and Europe, however they did not exist in Polish industry. The supply base was non-existent and little expertise in any of the technologies proposed existed outside of academia. Guidance and support from the United States was provided within a robust International Trade Compliance (ITC) process with special emphasis on avoiding inadvertent exports of manufacturing "know how". This program was a "first" in terms of technology and size for PZL Mielec, therefore an appropriate program management structure and culture was created and coached to insure proper control of projects replete with discovery. This paper explores the cultural as well as the technological aspects that led to a successful conclusion of the program in the spirit of the Vertical Flight Society: "…engineers, scientists and others working to advance vertical flight technology".
Additive Manufacturing (AM) of a Rotorcraft Gearbox Housing Independent Research & Development (IRAD) Project
Authors:   The Boeing Company, Cross Gerald , Filler Robert , Research Boeing
Published: July 2023

Boeing's Advanced Drive Systems Engineering group explores the application of metallic Additive Manufacturing (AM) for reducing the development time for fabricating rotorcraft gearbox housings. In order to accomplish this, it required that a satisfactory level of material and process evaluation, mechanical coupon testing, part design, part analysis, and bench testing be conducted. The information presented in this paper provides an overview of the various phases of this effort.
Additive Manufacturing of C64 for Aerospace Gear Applications
Authors:   US Army CCDC AvMC, Fetty Jason
Published: July 2023

Additive manufacturing (AM) is a novel process of fabricating components in a layer-by-layer method under the control of computer-aided design (CAD) information, rather than by the traditional use of casting molds and forming dies. By allowing for net-shape fabrication of highly complex geometries without molds or machining, this process offers the potential to reduce material usage, energy consumption, component cost, and fabrication time. While AM presents the unique opportunity to manufacture single components quickly, it also provides for the potential to examine the effects of individual design alterations on overall system performance.

QuesTek has utilized its proven Integrated Computational Materials Engineering (ICME) methodology to adapt Ferrium® C64® steel for additive manufacturing, where the market availability of AM gear steels is very limited. QuesTek has demonstrated success in AM-processing of C64 using a laser-based powder bed technique, from procurement of powder through final test part fabrication. This production route is demonstrating the ability to fabricate a near-net shaped part at a reduced cost and significantly reduced lead time relative to conventional manufacturing routes, making it especially useful for rapid prototyping of new components.
Selective Laser Melting of Aluminum Based Materials
Authors:   PZL Mielec, Wojtuszewski Radoslaw , Banas Aleksander , Oliwa Mateusz
Published: July 2023

Selective Laser Melting is a technology that can be used with various materials including aluminum alloys. The most common and suitable for SLM are AlSi10Mg and AlSi12Mg. Scalmalloy is a innovative material that can be used as high-strength alternative for the mentioned materials. Aluminum alloys are also widely utilize in aircraft production. Selective Laser Melting technology with an appropriate material can be used as substitute of traditional casting or forging technology. Thanks to good mechanical properties and printability of Scalmalloy it can be easily used for this purpose. The proposed paper consists for part which covers fundamental knowledge about AM industry, technology basics and general description of SLM. Technology capabilities with particular emphasis on most part quality influential areas are shown. Second part covers results from mechanical testing. Results from static tests are presented as well as results from quality control reports. According to authors experience the best quality control procedures are shown. Within third section technology substitution for certain parts is presented taking into account part quality, strength, good printability and costs. For some parts non-destructive and destructive tests results were demonstrated.
The Aerodynamic Effect Of An Oblique Wind On Helicopter Recovery To The Queen Elizabeth Class Aircraft Carrier
Authors:   University of Liverpool, Watson Neale , Kelly Michael , White Mark , Owen Ieuan
Published: July 2023

This paper describes an investigation into the air flow over the flight deck of HMS Queen Elizabeth, the UK's new aircraft carrier, and how it could affect helicopter recovery. The twin islands on the starboard side of the ship mean that there will be turbulent air flow over the flight deck for starboard winds. The unsteady air flow over the ship was created using time-accurate Computational Fluid Dynamics for a 25kts wind coming from 25° off the starboard, i.e. a Green 25 wind over deck. As well as using the CFD results to show the expected mean velocity field and turbulence intensity over the flight deck, the time-varying velocity components have also been used to assess how the unsteady air flow will affect a helicopter by integrating the velocity components of the ship’s airwake with a flight dynamics model of a helicopter configured to represent a SH-60B Seahawk. The application of the helicopter flight dynamics model has been implemented in two different ways: first where the flight model is held stationary in the airwake to evaluate the unsteady aerodynamic loads imposed on the helicopter, and second where the airwake and the flight model are integrated into a piloted full-motion flight simulator to assess pilot workload during a series of deck landings. The results show how the turbulent air flow over the landing spots correlates with the predicted unsteady loads on the helicopter, and with the workload ratings awarded by a test pilot in the simulator.
Model-based Uncertainty Quantification, Propagation, and Analysis using Generalized Polynomial Chaos
Authors:   Barron Associates Inc., Cooper Jared ,   Systems Technology Inc., Klyde David , DeVore Dr. , Reed Adam
Published: July 2023

This article introduces a probabilistic model-based programming language called AURA-Sim that enables the quantification, propagation, and analysis of arbitrary random distributions through nonlinear systems. Probabilistic programming languages are a relatively recent innovation that are intended to automate much of the low-level programming required to implement common statistical computations. Model-based programming languages are designed to simplify the specification of complex dynamical systems, having many separate components that interact over time, and are widely used for developing complex systems in numerous disciplines. This articles explains the harmonious combination of these two programming concepts into a unified programming language that enables system designers to directly solve many of the most important problems of uncertainty management for dynamical systems. The resulting language is developed as a set of C++ libraries and exposed to the user in the model-based language of SIMULINK and MATLAB. AURA-Sim allows system designers to model essentially arbitrary random processes and to propagate them through a wide variety of nonlinear dynamical systems. This capability is not currently available in any model-based programming language. The AURA-Sim library is based on generalized polynomial chaos (gPC) theory which is reviewed in the following. Traditionally, uncertainty quantification, propagation, and analysis has been conducted using Monte Carlo simulation; however, Monte Carlo simulations often incur a high computational cost, are time consuming, and slow to converge. Even after dedicating the time and computational resources to perform exhaustive Monte Carlo analysis, comprehensive coverage of the uncertainty space is not assured and reasoning over the simulation results requires additional cost. The AURA-Sim approach offers the potential to provide comprehensive coverage with a single simulation run, drastically reducing the required cost. Reasoning and calculating inferential statistics from the results does not required large data sets because the simulation signals are represented as random quantities.
Multidisciplinary, Multiobjective Trim Optimization for a Coaxial-Pusher Rotorcraft Configuration
Authors:   University of Maryland, Herrmann Thomas , Celi Roberto , Baeder James
Published: July 2023

The control redundancy inherent to a coaxial helicopter facilitates multiple achievable configurations for trimmed flight conditions. These redundancies can be exploited to optimize performance across multiple disciplines including the minimization of noise and the maximization of component life. Improved trim methodologies are required to identify the control allocation for optimal multidisciplinary flight performance. Previously, the authors of this paper presented results of a coaxial rotorcraft multidisciplinary analysis. The initial parametric study of the effect of pusher propeller control on the aircraft power, noise, and rotor blade fatigue served as the basis and justification for development of optimization methods of control designs to meet multidisciplinary objectives. This paper builds on that previous work by describing the optimization methodology used to leverage trim control redundancy of coaxial rotorcraft. The results from optimizing two controls for three performance metric are presented. The impact of the control design schemes on the performance and the effectiveness of the methodology at predicting the optimal designs is discussed.
Development of a Probability of Hover Analysis Capability to Support Rotorcraft Conceptual Design
Authors:   US Army CCDC AvMC, Chen Geoffrey
Published: July 2023

The capability to hover has served as a defining characteristic of rotorcraft ever since the first flight. However, assuming fixed power and gross weight for a specific configuration, the capability to hover is directly dependent on the desired environment - the latter a function of the ambient pressure, altitude, and temperature. Following previous studies, it has been shown that a rotorcraft’s capability to hover in various environments can be represented by a single metric, the probability of hover. Therefore, an initial methodology has been developed that works with the rotorcraft design code NDARC [6] to determine said probabilities of hover for candidate aircraft in four example countries: Afghanistan, Iran, South Korea, and West Germany. This initial paper has specifically chosen to evaluate an advanced active rotor helicopter design at various gross weights and compute the corresponding probabilities of hover. The background, framework, results, and future increments of this capability are described in detail below.
Numerical study and optimization of a novel architecture of Vertiport and Vertistop for Urban Air Mobility
Authors:   Airbus Helicopters, Cacciavillani Edoardo , Ielmini Francesco
Published: July 2023

Currently the VTOL world sees a high number of players investing in electrification, especially coming from the lower end of the market: like commercial drones and startups. Electric engines allow for new architectures and configurations, and partially simplify the design.
Simplifying design, lowering cost of development and maintenance, has led to imagine the use of the eVTOL in the passengers' air transportation market, currently reserved to VIP and high net worth individuals. The shift is potentially so radical that a new name has been coined: Urban Air Mobility.
This new market is widely imagined as a radical change compared to the current situation: with more traffic, simplified procedures for boarding and in some cases the use of unmanned or remotely piloted vehicles. This leads to the conclusion that the whole transportation system architecture will have to be upgraded or modified to allow for this to happen. Many projects are already running in this direction regarding specific topics, like SESAR JU [1] for Air Traffic Management. This paper treats the Ground Infrastructure, what is commonly referred as Heliport. In the paper a novel architecture envisioned for Urban Air Mobility is proposed and analyzed.
A Modular Open System Approach for the US Army's Improved Turbine Engine
Authors:   PeopleTech Inc., Carter Casey ,   US Army ATE PO, Dutcher Danielle ,   Ranger Defense Inc., Suggs Daniel , Sipe Matthew , Rosengren Scott , Plummer Ben
Published: July 2023

The Improved Turbine Engine (ITE) Program, run by the US Army's Aviation Turbine Engine Project Office (ATE PO), has a multi-faceted Modular Open System Approach (MOSA) to reduce engine integration and sustainment costs, control schedule risks, and enable opportunities for future upgrades. The approach is an integrated business and technical strategy that employs a modular hardware and software design, leverages data rights, employs United States Government (USG) defined interfaces using consensus-based standards, and makes architectural decisions based on lifecycle intentions for maintenance, sustainment, and possible future competition.
HELIWISE: Tool for Helicopter Advanced HUMS Data Analysis
Authors:   Leonardo Helicopters, Prece Valerio
Published: July 2023

Purpose of this paper is to describe the new approach for the analysis of Health and Usage data implemented by Heliwise, a software tool developed by Leonardo Helicopters, and aimed to increase the aircraft availability (with reduction of unexpected Aircraft On Ground's) and to minimize the extraordinary maintenance activities. In this paper will be shown how Heliwise can achieve this result by implementing an architecture which is modular, flexible and suitable to operate in a global environment, a sort of HUMS technical community, where all data are shared.
Biofilm analyses and exoproduct release by clinical and environmental isolates of Burkholderia pseudomallei from Brazil
Authors: de Melo Guedes Glaucia Morgana , Ocadaque Crister José , Freitas Alyne Soares , Pinheiro Rodrigo Machado , Riello Giovanna Barbosa , Bandeira Silviane Praciano , de Aguiar Cordeiro Rossana , Gadelha Rocha Marcos Fábio , Costa Sidrim José Júlio , Castelo-Branco Débora de Souza Collares Maia
Published: July 2023

Objective:

To characterize biofilm production by clinical (n=21) and environmental (n=11) isolates of Burkholderia pseudomallei and evaluate the production of proteases, hemolysins and siderophores.

Methods:

Initially, the 32 strains were evaluated for biofilm production in Müller-Hinton broth-1% glucose (MH-1% glucose) and BHI broth-1% glucose, using the crystal violet staining technique. Subsequently, growing (48 h) and mature (72 h) biofilms were evaluated by confocal microscopy. Finally, the production of proteases, hemolysins and siderophores by planktonic aggregates, growing biofilms and mature biofilms was evaluated.

Results:

All isolates produced biofilms, but clinical isolates had significantly higher biomass in both MH-1% glucose (P<0.001) and BHI-glucose 1% (P=0.005). The structural analyses by confocal microscopy showed thick biofilms, composed of multiple layers of cells, homogeneously arranged, with mature biofilms of clinical isolates presenting higher biomass (P=0.019) and thickness of the entire area (P=0.029), and lower roughness coefficient (P=0.007) than those of environmental isolates. Protease production by growing biofilms was significantly greater than that of planktonic (P<0.001) and mature biofilms (P<0.001). Hemolysin release by planktonic aggregates was higher than that of biofilms (P<0.001). Regarding siderophores, mature biofilms presented higher production than growing biofilms (P<0.001) and planktonic aggregates (P<0.001).

Conclusions:

Clinical isolates have higher production of biofilms than their environmental counterparts; protease and siderophores seem important for growth and maintenance of Burkholderia pseudomallei biofilms.
Surveillance of emerging SARS-CoV-2 variants by nanopore technology-based genome sequencing
Authors: Abeynayake J. I. , Chathuranga G. P. , Fernando M.A.Y. , Sahoo M. K.
Published: July 2023

Objective:

To surveill emerging variants by nanopore technology-based genome sequencing in different COVID-19 waves in Sri Lanka and to examine the association with the sample characteristics, and vaccination status.

Methods:

The study analyzed 207 RNA positive swab samples received to sequence laboratory during different waves. The N gene cut-off threshold of less than 30 was considered as the major inclusion criteria. Viral RNA was extracted, and elutes were subjected to nanopore sequencing. All the sequencing data were uploaded in the publicly accessible database, GISAID.

Results:

The Omicron, Delta and Alpha variants accounted for 58%, 22% and 4% of the variants throughout the period. Less than 1% were Kappa variant and 16% of the study samples remained unassigned. Omicron variant was circulated among all age groups and in all the provinces. Ct value and variants assigned percentage was 100% in Ct values of 10-15 while only 45% assigned Ct value over 25.

Conclusions:

The present study examined the emergence, prevalence, and distribution of SARS-CoV-2 variants locally and has shown that nanopore technology-based genome sequencing enables whole genome sequencing in a low resource setting country.
Postvaccination breakthrough SARS-CoV-2 infections among adults in Malaysia and attitudes towards future vaccination
Authors: Nair Praneetha Kumar , Koh Kai Ern , Bede Christine Yvonne , Natasha Lee Ai Ren , Mahanama Mevuni Dinethma , Kyaw Thin Mon , Soe Htoo Htoo Kyaw , Moe Soe , Rahaman Kazi Majidur , Htay Mila Nu Nu
Published: July 2023

Objective:

To determine the frequency and severity of the breakthrough infections and the associated factors in Malaysia.

Methods:

This cross-sectional study was conducted among the adult general population in Malaysia who completed at least one dose of vaccination. The validated online questionnaires were used for data collection between December 2022 to February 2023. The participants were recruited by a convenient sampling method. The data were analysed by descriptive statistics, and logistic regression by using SPSS (Version 27). Qualitative data from open-ended questions were analysed as thematic analysis by using RQDA software.

Results:

A total of 524 participants' data were analyzed and 77.5% of them completed three doses of COVID-19 vaccination. Breakthrough infections after vaccination were reported in 57.3% of the participants. Age group of 18 and 30 years (aOR 2.32, 95% CI 1.01-5.32) and other ethnicities (aOR 2.00, 95% CI 1.02-3.93) significantly associated with the occurrence of breakthrough infections. A total of 35.5% of the participants were not willing to take another booster dose in the future because of their attitudes towards fear of long-term side effects, lack of trust to the vaccine, less susceptibility to severe infection, belief in natural immunity, and myths.

Conclusions:

Future public health policies and interventions should be focused on disseminating the information about safety of booster doses of vaccine, management and re-assurance of side effects, and targeted vaccination to the working (younger age group) and ethnic minorities.