bluuebunny/crossref_metadata_2025 huggingface dataset:
Stability of Solution of Quasilinear Parabolic Two-Dimensional with Inverse Coefficient by Fourier Method
Authors: BAĞLAN İrem
Published: June 2023

In this article, the heat inverse two-dimensional quasilinear parabolic problem is examined. The stability and numerical solution for the problem are discussed.Since the problem is not linear, Picard's successive approximations theorem is used. In the numerical part, the solution is made with the finite difference and linearization method.
High-energy Neutrino Emission Associated with Gravitational-wave Signals: Effects of Cocoon Photons and Constraints on Late-time Emission
Authors: Matsui Riki , Kimura Shigeo S. , Toma Kenji , Murase Kohta
Published: June 2023

We investigate prospects for the detection of high-energy neutrinos produced in the prolonged jets of short gamma-ray bursts (sGRBs). The X-ray light curves of sGRBs show extended emission components lasting for 100–1000 s, which are considered to be produced by prolonged engine activity. Jets produced by such activity should interact with photons in the cocoon formed by the propagation of the jet inside the ejecta of neutron star mergers. We calculate neutrino emission from jets produced by prolonged engine activity, taking account of the interaction between photons provided from the cocoon and cosmic rays accelerated in the jets. We find that IceCube-Gen2, a future neutrino telescope, with second-generation gravitational-wave detectors will probably be able to observe neutrino signals associated with gravitational waves with around 10 years of operation, regardless of the assumed value of the Lorentz factor of the jets. Neutrino observations may enable us to constrain the dissipation region of the jets. We apply this model to GRB 211211A, a peculiar long GRB whose origin may be a binary neutron star merger. Our model predicts that IceCube is unlikely to detect any associated neutrinos, but a few similar events will be able to put a meaningful constraint on the physical quantities of the prolonged engine activities.
Merger Conditions of Population III Protostar Binaries
Authors: Kirihara Takanobu , Susa Hajime , Hosokawa Takashi , Kinugawa Tomoya
Published: June 2023

Massive close binary stars with extremely small separations have been observed, and they are possible progenitors of gravitational-wave sources. The evolution of massive binaries in the protostellar accretion stage is key to understanding their formation process. We, therefore, investigate how close the protostars, consisting of a high-density core and a vast low-density envelope, can approach each other but not coalesce. To investigate the coalescence conditions, we conduct smoothed particle hydrodynamics simulations following the evolution of equal-mass binaries with different initial separations. Since Population (Pop) I and III protostars have similar interior structures, we adopt a specific Pop III model with the mass and radius of 7.75 M
⊙ and 61.1 R
⊙ obtained by the stellar evolution calculations. Our results show that the binary separation decreases due to the transport of the orbital angular momentum to spin angular momentum. If the initial separation is less than about 80% of the sum of the protostellar radius, the binary coalesces in a time shorter than the tidal lock timescale. The mass loss up to the merging is ≲3%. After coalescence, the star rotates rapidly, and its interior structure is independent of the initial separation. We conclude that there must be some orbital shrinking mechanism after the protostars contract to enter the zero-age main-sequence stage.
Nonparametric Model for the Equations of State of a Neutron Star from Deep Neural Network
Authors: Zhou Wenjie , Hu Jinniu , Zhang Ying , Shen Hong
Published: June 2023

It is of great interest to understand the equation of state (EOS) of the neutron star, whose core includes highly dense matter. However, there are large uncertainties in the theoretical predictions for the EOS of a neutron star. It is useful to develop a new framework, which is flexible enough to consider the systematic error in theoretical predictions and to use them as a best guess at the same time. We employ a deep neural network to perform a nonparametric fit of the EOS of a neutron star using currently available data. In this framework, the Gaussian process is applied to represent the EOSs and the training set data required to close physical solutions. Our model is constructed under the assumption that the true EOS of a neutron star is a perturbation of the relativistic mean-field model prediction. We fit the EOSs of neutron star using two different example data sets, which can satisfy the latest constraints from the massive neutron stars, NICER, and the gravitational wave of the binary neutron stars. Given our assumptions, we find that a maximum neutron star mass is

2.38

−
0.13

+
0.15

M

⊙

or

2.41

−
0.14

+
0.15

M
⊙

at the 95% confidence level from two different example data sets. It implies that the 1.4M
⊙ radius is

12.31

−
0.31

+
0.29

or

12.30

−
0.37

+
0.35

km. These results are consistent with results from previous studies using similar priors. It has demonstrated the recovery of the EOS of NS using a nonparametric model.
Crustal Failure as a Tool to Probe Hybrid Stars
Authors: Pereira Jonas P. , Bejger Michał , Haensel Paweł , Zdunik Julian Leszek
Published: June 2023

It is currently unknown if neutron stars (NSs) are composed of nucleons only or are hybrid stars, i.e., in addition to nucleonic crusts and outer cores, they also possess quark cores. Quantum chromodynamics allows for such a possibility, but accurate calculations relevant for compact stars are still elusive. Here we investigate some crust-breaking aspects of hybrid stars. We show that the crust-breaking frequency and maximum fiducial ellipticity are sensitive to the quark–hadron density jump and equation of state stiffness. Remarkably, the crust-breaking frequency related to static tides scales linearly with the mass of the star (for a given companion mass), and its slope encompasses information about the microphysics of the star. However, for precise crust-breaking frequency predictions, relativistic corrections to Kepler’s third law and the Newtonian tidal field should not be ignored. When a liquid quark core touches an elastic hadronic phase (the result of a significant energy density jump), the maximum ellipticity can increase by around an order of magnitude when compared to a liquid quark core touching a liquid hadronic phase. That is relevant because it would increase the odds of detecting continuous gravitational waves from NSs. Our order-of-magnitude analysis also suggests that a given upper limit to the ellipticity (crust-breaking frequency) could have representatives in stars with either small or intermediate (large) energy density jumps. Therefore, when upper limits to the ellipticity for isolated stars are better constrained or electromagnetic radiation (e.g., gamma-ray precursors) is detected along with gravitational waves in inspiraling binary systems, they may help constrain some aspects of phase transitions in NSs.
CHARACTER OF WAR: HOW TO UNDERSTAND IT?
Authors: ŽILINČÍK Samuel , PIKNER Ivo , STANĚK Jaroslav
Published: June 2023

Strategic theory dictates that an understanding of a war’s character is imperative for the achievement of victory in strategic practice. This article identifies and analyses extant approaches to the understanding of war. These approaches include categorization, strategic analysis and historical comparison. A theoretical analysis accompanied by illustrative cases indicates that one can achieve the most in-depth understanding of a war’s character by combining strategic analysis and historical comparison, though the process of achieving such understanding is difficult and time-consuming.
AN ALTERNATIVE MODEL FOR DETERMINING THE RATIONAL AMOUNT OF FUNDS ALLOCATED TO DEFENCE OF THE CR.
Authors: ŠLOUF Vlastimil , BLAHA Martin , PEKAŘ Ondřej , BRIZGALOVÁ Lenka , MÜLLNER Vojtěch
Published: June 2023

The present paper presents an alternative approach to determining rational defence spending of the Czech Republic concerning the evolution of a society’s wealth, expressed in terms of the financial valuation of tangible fixed assets. The authors describe the view that the government’s stated commitment to defence spending of 2% is a political decision that does not reflect the impact of the wealth achieved by society, the likelihood of an attack by a foreign power, and the expected level of damage caused by an attack. The authors present a model for determining rational defence spending based on the fair insurance model. The authors conclude that the rational expenditure on the defence of the Czech Republic’s wealth should be between 3.5% and 4.2% of GDP.
A new species of the paper wasp genus Ropalidia Guérin-Méneville, plebeja group (Hymenoptera, Vespidae, Polistinae), from Vietnam
Authors: Bui Hoa Thi Quynh , Mai Thai Van , Nguyen Lien Thi Phuong
Published: June 2023

A new species, Ropalidia daklak Bui, Mai & Nguyen, sp. nov., belonging to the plebeja-group of the genus Ropalidia Guérin-Méneville, 1831 is described and figured based on females and males from Vietnam. The nest structure of the new species is described, and an updated key is provided to all known species of the group.
Uneven species occurrence and richness of lowland snakes (Serpentes, Squamata) in Terengganu, Peninsular Malaysia, with new locality records
Authors: Syafiq Muhamad Fatihah , Badli-Sham Baizul Hafsyam , Grismer Larry Lee , Ahmad Amirrudin B.
Published: June 2023

This study documents information on the composition, diversity, richness, and temporal occurrence of snakes at Sekayu’s lowland forest (SLF), Terengganu, Peninsular Malaysia for the first time. The snakes recorded within the SLF were sampled opportunistically from 2013 to 2019, employing the Visual Encounter Survey method (VES) and L-shape pitfall traps with drift fences. Forty-six snake species from 37 genera belonging to the nine families were recorded, of which 11 were new records to Terengganu. Individual-based rarefaction and extrapolation curves were not reaching asymptote, indicating that additional species can be recorded at the study area. Non-parametric species richness estimators estimated and produced a range between 51 and 57 species. ACE was the best estimator based on the quantitative evaluation. All species showed some variations of occurrence patterns across months. Fourteen species were only encountered once across the sampling years, and interestingly 11 of them were only detected during the rainy season (late October to January). In general, the number of species richness, abundance, and rare species were high during this season. Species richness of snakes is high at SLF but sampling effort should be intensified, especially during these rainy months, to obtain a robust estimated snake species richness in SLF. Terengganu harbor considerably high species richness of snakes with a total of 71 species to date (excluding marine snakes), but snake diversity is still underestimated as only a few localities were surveyed in the past years, primarily at the northern part. Future surveys should be commenced at the central and southern parts of Terengganu to complement the current investigation.
Royaume-Uni. Le gouvernement britannique veut restreindre le droit de grève en réponse à un mouvement social historique
Authors: Connolly Heather
Published: June 2023

Au Royaume-Uni, les mouvements de grève de 1978-1979 et 2010-2011 ont été suivis par la mise en œuvre de restrictions légales au droit de grève. Ceux de 2022-2023, historiques par leur ampleur, ne font pas exception avec la proposition du gouvernement de mettre en place un service minimum pour limiter l’efficacité des grèves. L’article analyse l’impact potentiel de la mise en place du service minimum, notamment dans le secteur ferroviaire, où la législation proposée est susceptible d’avoir l’impact le plus important.
Surface family pair with Bertrand pair as mutual geodesic curves in Euclidean 3-space $ \mathbb{E}^{3} $
Authors: Almoneef Areej A. , Abdel-Baky Rashad A.
Published: June 2023

The main interest of this work is to construct surface family pair with the symmetry of Bertrand pair in Euclidean 3-space $ \mathbb{E}^{3} $. Then, by employing the Serret-Frenet frame, we conclude the sufficient and necessary conditions of surface family pair interpolating Bertrand pair as mutual geodesic curves. Moreover, the conclusion to ruled surface family pair is also obtained. Meanwhile, this work is demonstrated through several examples.
Assessing intellectual capital performance of banks during COVID-19: Evidence from China and Pakistan
Authors: Xu Jian , Haris Muhammad , Irfan Muhammad
Published: June 2023

Using quarterly data from 2019Q1 to 2020Q3, this study aims to examine the impact of COVID-19 on intellectual capital (IC) performance of banks operating in China and Pakistan. Based on the data of 34 Chinese and 41 Pakistani banks, this study applies the fixed effect method to examine this relationship, and the value added intellectual coefficient (VAIC) model is used to measure IC performance. The study shows a negative but insignificant influence of COVID-19 on IC performance of the banking sector in both countries. Likewise, the findings exhibit that IC components show resilience against COVID-19 and are slightly influenced by this crisis. The results are also consistent in robustness check. The cross-country comparison suggests that the performance of IC components in the Pakistani banking sector is higher compared to China. This is the first study that examines the impact of COVID-19 on IC performance of banks, and it might provide insights regarding the influence of crises such as COVID-19 on IC performance of banks in emerging economies.
Knowledge Management Data Collection for Public Safety Priority Communications
Authors: Kheng Liz
Published: June 2023

Many of the tragedies of 9/11 could have been prevented if not for the failure of commercial cellular networks that were flooded with public calls. These calls caused a bottleneck in the first responder communication systems. Because of these failures, President Obama signed the Middle-Class Tax Relief and Job Creation Act of 2012. Part of the law designates the 700 megahertz band block D spectrum allocated to public safety. In June 2014, the State of Ohio issued a Request for Quotation (RFQ) seeking a vendor for OhioFirst.Net National Public Safety Broadband Network (NPSBN) State and Local Implementation Grant Program (SLIGP) Support. The winning vendors, Advocate Technical Services and Televate, were tasked with building a project plan for Ohio First and gathering data to help the state of Ohio develop a business plan for National FirstNet. This business case study follows the Ohio FirstNet Project from a knowledge management perspective.
Challenges Faced by a Global Organization and Their KMS Implementation
Authors: Gross Brenda
Published: June 2023

Worldwide Connectivity Solutions (WCS) is a global enterprise. The purpose of this teaching case study is to describe the process WCS followed in selecting and implementing Helpjuice as its knowledge management system (KMS). Helpjuice is an easy-to-use WCS that faced numerous challenges that impacted revenues, shareholder dividends, employee retention, and a workforce needing more experience and knowledge to complete assigned tasks. Lengthy connectivity outages have impacted emergency services, leading to record-high fines imposed by the FCC. To overcome these challenges, WCS established a team to analyze the affordability of implementing a knowledge management system (KMS). As a result of the analysis, the team recommended that WCS implement Helpjuice as their KMS. This teaching case study describes the affordability analysis, challenges, strengths, organizational culture, KMS implementation, audit process, and multicultural perspectives. Lastly, a list of discussion topics and questions is included.
Intelligent Packaging
Authors: Palazzo Maria , Gigauri Iza , Ferri Maria Antonella
Published: June 2023

Digitalization and sustainable development present a twin transition to the industry 5.0-based new normal. Companies try to achieve sustainability transformation through new business strategies in order to respond to the demand of their stakeholders. For this reason, food companies are striving to apply sustainability principles in product packaging design while considering the complete life cycle of a product. Therefore, intelligent packaging with sensor technologies and extended functions is emerging. It uses digital systems to package food to obtain real-time information on the features of goods during transportation or storage. While controlling the condition of food and the surrounding environment, it informs the manufacturer, retailer, or consumer of the state of the food. Therefore, the demand for intelligent packaging is growing in the food industry. This chapter explores intelligent packaging and defines the current trends in this innovative field.
Re-Innovative Organizational Design
Authors: Stefanova Dimitrina Petrova , Vasilev Valentin Penchev , Efremovski Ivan Petre
Published: June 2023

Dynamics and crises in the present are inextricably associated with company growth and change management in the context of today. In this way, the question of innovation in management processes has evolved, and we now focus on re-innovative organizational practices that expand on and improve tried-and-true methods. In such a situation, the function of sustainable branding is that effective communications are essential tools for adapting to the climate and chaotic characteristics. Additionally, the long-lasting and unexpected pandemic crisis, a technologically advanced and globally integrated society and economy, and the hybridity of change all have a significant impact on marketing procedures. Although the subject is broad, the research's primary focus is on creating a dialogic, motivated, and productive management style, with new internal communication channels playing a key role as a component of branding.
Design of Business Processes for Marketing Activity
Authors: Tevdoradze Medea , Darchia Samson , Rukhadze Tamta
Published: June 2023

As it is known, marketing plays a huge role in the activity of companies, which ensures the company's success in the market. Today the majority of companies have moved to process management, which because of some reason often is not applied to marketing activities and this has a negative impact on it. In order to correct the situation, this chapter serves the issues of design of business processes of marketing activities in the company. It is characterized by a marketing complex (4P model). Also, there are discussed holistic marketing features and marketing strategy issues, there are realized procedures which are necessary for management of marketing activities. But, the peculiarity of marketing activity is that, in addition to ERP-type programs, it is necessary to use a specialized marketing information system, which is due to the abundance and complexity of the models that must be used in the process of marketing evaluations. It is underlined that ERP-type and marketing information system must be used in the complex.
The Impact of Social Marketing and Corporate Social Responsibility on Energy Savings as a Competitive Strategy
Authors: Mızrak Filiz , Cevher Muhammed Fatih
Published: June 2023

In today's globalizing world, corporate social responsibility has become a necessity for businesses. The corporate social responsibility approach, which is based on the principles of giving back to the society what it has taken from the society and observing the benefit of the society in the activities of the enterprise, has an important place in terms of promoting the products and services they produce in the market under the best conditions and strengthening the brand image. From this point of view, corporate social responsibility is seen as a valid practice to make a difference. However, businesses mostly carry out social marketing activities for this purpose. Thus, while trying to find solutions to social problems, they can obtain a competitive strategy. In this context, the aim of the study is to show that the energy crisis, which is one of the most serious problems of today, can be solved by raising awareness in consumers with corporate social response activities and social marketing methods.
Estimation of confidence margins for Direct Load Recognition (DLR) using supervised and unsupervised machine learning
Authors:   Airbus Helicopters S.A.S., Jouve Jeremy , Gallimard Caroline , Nikolajevic Konstanca , Morel Herve
Published: June 2023

One of the key challenges of any helicopter manufacturer lies in the competiveness of its products compared to its competitors. Operating costs is clearly one of them. Taking into account the complexity to maintain in operational and airworthy conditions a helicopter, substantial gains are achievable through the optimization of the Direct Maintenance Cost (DMC). Over the last decades, significant improvements have been made on mandatory enablers of such technologies, as for example Data Based Models (DBM), Predictive Maintenance (PM) or Conditions (Usage) Based Maintenance (CBM). More and more complex approaches were elaborated, getting always closer from true helicopter behavior, but certification has often been a hindrance to development, as infallible evidences are difficult to build. Thus, instead of pushing for additional improvement to gain limited performances, this paper presents an alternative way, taking uncertainties as an intrinsic component of the prediction. Similarly to fatigue metallic, choice is made to live with uncertainties, but to confine them thanks to statistics approaches based on the estimation of confidence intervals around a prediction. Through the paper, three methods have been explored, Euclidean proximity (K-Nearest Neighbors, KNN), unsupervised learning (Self-Organizing Map) and supervised learning (Conformal Prediction). This broad, largescale exploratory analysis, has demonstrated that reasonable intervals, which would not prevent any gain from a Condition Based Maintenance approach, can be defined and shall be now compared with certification authority's preliminary targets.
A Holistic Comparison of a Trailing Edge Rib Demonstrator Made with Three Different PEEK Thermoplastic Composite Form Factors: Unidirectional, Fabric and Braid
Authors:   Teijin Carbon America, Lopez Alfonso ,   Wichita State University, Kariyawasam Supun ,   ATC Manufacturing, Postera Richard ,   A&P Technology Inc., Carrol Brennan , Spangler Joe , Seneviratne Waruna , Leach David , Wood Billy
Published: June 2023

This study investigates the forming quality and mechanical performance of a trailing edge rib made with three different carbon fiber PEEK form factors, tape, fabric, and braid. It was found tape ribs developed the most severe level of wrinkling and waviness leading to premature ILT failure in the flange. This contrasted with braid and fabric ribs, which failed in compression buckling and had almost three times the deformation before ultimate failure. Moreover, the reinforcement form factor, combined with a high elongation to break matrix like PEEK, was found to have a significant effect on crack propagation and toughness leading to the different failure modes. The trade-offs between tape, fabric and braid form factors are similar to those with thermosets, but seemingly exaggerated, considering fabrics and braids displayed a large amount of plastic deformation while PEEK tape laminates displayed failure progression similar to thermoset composites. These findings have important implications for the design and optimization of thermoplastic composites in new aerial mobility vehicles expected to operate at higher frequency in environments with more varied damage hazard potential.
Factory Planning through Modeling and Simulation
Authors:   Sikorsky A Lockheed Martin Company, Keane Devon
Published: June 2023

The application of 3D modeling and simulation has advanced our capabilities to be more agile, collaborative, and efficient through a lean six-sigma approach. As our aircraft grow more complex, so does our factory and our manufacturing processes that are contained within. There is an inherent need to be agile throughout all our processes, from design, to assembly, and ultimately throughout aircraft sustainment. The progression in areas such as model based definition, discrete event process models, and extended reality technologies (such as Virtual Reality, Augmented Reality, and Immersive Reality) are all key enablers to be able to adapt as both our production and our customer demands grows. Now more than ever, a digital representation of our manufacturing work cells is critical to success and will allow us to maintain a competitive edge.
System Identification of a Compound Intermeshing Rotor UAV
Authors:   DLR (German Aerospace Center), Wartmann Johannes , Seher-Weiß Susanne , Petit Philippe , Dikarew Alexej , Voigt Andreas , Fettig Kristian
Published: June 2023

Within the FaUSt (Fast Unmanned Scout) project, an existing UAV with intermeshing rotors was enhanced by two electric pusher propellers to extend the speed range for future manned-unmanned teaming research. The modeling of such a compound UAV has not yet been covered in the literature. To extract models for simulation and flight control design, dedicated flight tests were performed using a multi-axis binary noise signal for system identification with activated base flight control system. Two different system identification methods are applied to estimate bare-airframe models of the modified UAV at hover condition: one in the time domain, the other in the frequency domain. The time domain method can inherently be applied to correlated closed-loop data, while input correlations have to be accounted for when using the frequency domain method. The resulting models are analyzed in both time and frequency domain and the model eigenvalues and modes are compared in detail. The results indicate that the time-domain model matches low frequency modes of the vehicle more accurately, but both models show good model performance.
Integrated Reality In-flight Simulation (IRIS): The Developmental Challenges
Authors:   National Research Council of Canada - NRC, Comeau Perry , Wall Alanna , Ellis Kris , Gubbels Arthur
Published: June 2023

The National Research Council Canada (NRC) and Defence Research and Development Canada (DRDC) have developed modelling and simulation tools intended to de-risk, increase efficiency and standardize Ship Helicopter Operating Limitations (SHOL) testing through the use of modelling and simulation. The Integrated Reality In-Flight Simulation (IRIS) tool is a novel simulator platform where an evaluation pilot (EP) flies a variable stability aircraft while wearing a virtual reality (VR) headset with many elements of the shipboard environment carefully reproduced including the injection of real time turbulence models established from wind tunnel trials. The turbulence and other environmental effects on the aircraft motion are coupled directly into the aircraft in real time, thereby retaining accurate critical proprioceptive and vestibular cueing for the pilot. NRC has recently completed flight test evaluations of the prototype concept. Pilot comments from initial testing indicated that the system required little adaptation, presented no noticeable lag, no attributable propensity to cause motion sickness, and that the turbulence felt realistic.The testing indicated that typical VR deficiencies such as resolution and field of view are not as impactful during close-in shipboard operations, making this application very effective.
Validation of a Flexible and Highly Scalable Mid-fidelity Aerodynamic Solver with Wind-tunnel Testing
Authors:   Leonardo Helicopters, Sabatino Enrico ,   Leonardo Labs, Sciarappa Antonio , Prederi Davide , Petri Fabrizio , Cassinelli Carlo , Frassoldati Gregorio
Published: June 2023

The design process of new VTOL vehicles is a challenging task that demands the synergy of many disciplines, such as flight mechanics, aerodynamics, structural dynamics, loads and aeroelasticity. Within this frame of reference, GyroX is an in-house aeroelastic simulation software developed by Leonardo Helicopters meant to integrate all of the previous disciplines. It hence aims to provide a fast and reliable numerical tool for aeroelastic and aeromechanical simulations of complex rotorcraft configurations. Indeed, GyroX gathers more than 25 years of experience in rotorcraft simulations and lays the way towards a multi-comprehensive tool for aircraft design and analysis.The purpose of this work is to present the tool and to assess the accuracy of a set of aerodynamic mid-fidelity numerical methods available in GyroX, with respect to rotor performances obtained during wind tunnel test campaigns.
Helicopter Aerodynamic Loading in the Airwake of a Moving Ship
Authors:   University of Liverpool, Fernandez Nicholas ,   National Research Council Canada, Wall Alanna , Owen Ieuan , White Mark , Lee Richard , Yuan Weixing
Published: June 2023

This paper presents an analysis of the unsteady aerodynamic loading of a helicopter immersed in the airwake of a generic destroyer undergoing several ship motion types: static, sinusoidal pitching, regular 2-DOF, and realistic irregular 3-DOF ship motions. The study was a collaborative effort between the National Research Council Canada and the University of Liverpool, where each organization have applied their respective modeling approach (whether by simulation or experiment). It was shown that whilst there were only marginal differences in the mean helicopter loads for each motion type, the effects of ship motion are more apparent in the RMS loads, and the instantaneous load and air-velocity spectra. Dominant peaks in the thrust load spectra, as well as subsequent second and third harmonics, are shown at the ship motion frequency for sinusoidal pitching and regular 2-DOF ship motions, which have been attributed to the interaction between the turning rotor and the moving ship. This analysis provides a foundation for understanding the relationships between ship airwake and helicopter loading, and for extending that understanding to impacts on flight operations.
Hamiltonian and Port-Hamiltonian Mechanics as A Possible Alternative for Helicopter Flight Dynamics Representation
Authors:   Delft University of Technology, Pavel Marilena
Published: June 2023

In the case of complicated, non-linear problems where simulations in the time-domain are needed to understand systems' behavior, Hamiltonian formulation can be used to obtain insight into system evolution in time. Hamiltonian dynamics has two advantages: 1) there is no need to write down the complete equations of motion explicity and thus help to solve the problem much quicker and 2) it can help understanding and designing controllers using the energy flow, Hamiltonian phase space and port-Hamiltonian representation for system evolution. The present paper highlights the importance of using the Hamiltonian dynamics for helicopter flight dynamics, exemplifying it for the helicopter pitch motion and for a 6-DOF nonlinear model. The paper shows that, using Hamiltonian formulation, one can define energy stagnations areas in the Hamiltonian phase plane and dissipative non-passive terms in the equations of motion that need to be restrained when designing a helicopter controller. The extension of the Hamiltonian to the port-Hamiltonian formulation can be used to design nonlinear controllers robust to system nonlinearities.
Concept of Operations in Aviation Industry – A Procedure Based Approach for Developing Novel Aerial Systems
Authors:   Technical University of Munich, Maly Markus , Hoffelner Julius , Krammer Christoph , Wechner Maximilian , Jaisle Jerg , Holzapfel Florian
Published: June 2023

In the last decades, Unmanned Aerial Systems (UAS) have been used extensively for various purposes. Consideringthe advantages of UAS compared to conventional manned aircraft, such as lower manufacturing and operating costs, UAS are creating a new industry with sizable economic potential. In this article, we introduce a novel procedure-based approach for developing a Concept of Operations (ConOps) document that integrates best practices from the aviation industry. A ConOps document should be defined to develop and operate a UAS safely. Since different guidelines are available that attend to different ConOps content, there needs to be a transparent process definition of how to generate a ConOps. In previous works, we developed and published a procedure-based methodology for aircraft design, initially intended for the development of optionally piloted vehicles.The ConOps process in this paper builds upon the existing aircraft development process and follows aviation standards, for example, SAE ARP4754A. Hence, ensuring maximum traceability, conformity, and integration with existing aviation guidelines is achievable while keeping flexibility as high as possible and supporting an agile development process. This novel process is independent of the mission goals and can be applied to manned, unmanned, and optionally piloted aircraft. The first insights from our practical experience in applying the new process are also presented.
CFD Thermal Analysis of an AH-64 Engine Bay
Authors:   The Boeing Company, Casaday Brian , Tang Justine
Published: June 2023

The Boeing AH-64 Apache is upgrading its twin GE T700-701D engines to the GE T901 engines in order to enhance the aircraft's capabilities. The engine nacelle is cooled with an exhaust eductor, and the integration of the new engines needs to be analyzed to ensure that temperature requirements are satisfied. A CFD model was developed to predict temperatures throughout the nacelle for both the port and starboard engines. This model incorporates surface-to-surface radiation and over a dozen inflow or outflow boundary conditions. Several sensitivities were analyzed in CFD, including a turbulence model and wall function comparison, and sensitivities to gravity, radiation, external airflow, and multiple other boundary condition assumptions. These sensitivities provide valuable information as to which parameters are necessary for accurately predicting component temperatures in these types of analyses. Future testing will be used to validate the results.
III Congresso Nazionale Filiera delle carni di selvaggina selvatica | Foligno 10 • 11 • 12 maggio 2023
Authors: Editors The
Published: June 2023

This abstract book contains the abstracts presented at the 3th National Congress Filiera delle carni di selvaggina selvatica, Foligno 10-11-12 May 2023 [In italian]
Comparison of the number of bacterial colonies among four types of suture threads using simple loop method following periodontal surgery in patients with periodontitis: A single-blind randomized clinical trial
Authors: Naghsh Narges , Yaghini Jaber , Arab Atefeh , Soltani Samaneh
Published: June 2023

Background:

This study investigated the number of bacterial colonies in four types of suture threads, including silk, nylon, monocryl, and monocryl plus after periodontal surgery in patients with moderate-to-severe periodontitis.

Materials and Methods:

In this single-blind randomized clinical trial, a total of 12 patients with periodontitis who required periodontal flap surgery in all quadrants were included. One type of suture, either silk, nylon, monocryl, or monocryl plus (coated with triclosan), was used following each surgery in each quadrant. Sutures (3 mm) were removed from the mid, posterior, and anterior regions of the flap 7 days postoperatively, and placed in a tube-containing buffer medium to transfer to the culture medium in a laboratory. Then, the bacterial colonies on each culture medium were counted manually. Finally, the mean number of grown colonies (anaerobic and aerobic) was computed and compared in each group of sutures. Data were analyzed by SPSS (Version 20) using the repeated measures ANOVA and least significant difference follow-up tests (α = 0.05).

Results:

The findings of this study indicated a significantly higher mean number of aerobic, anaerobic, and aerobic-anaerobic colonies in silk suture than in the other three types of sutures (P < 0.05). However, no significant difference was observed among other types of sutures (P > 0.05).

Conclusion:

The results of this study showed that silk suture had a higher bacterial adhesion (aerobic, anaerobic, and aerobic-anaerobic) than monofilament sutures, including nylon, monocryl, and monocryl plus. Moreover, no significant difference was found among the monofilament sutures in the number of colonies grown on them.
Management of compromised residual alveolar ridges using hollow denture with three-dimensional printed spacer and specialized impression technique
Authors: Singh Navdeep , Dua Parag , Thiruvalluvan N. , Kumar Saurav , Yangchen Sonam
Published: June 2023

Impression making in compromised residual alveolar ridge is a regular challenge in rehabilitating patients with conventional removable complete dentures. In patients who cannot afford implant-supported dentures, specialized impression technique is a viable and justified option for fabrication of complete dentures. More often, the stability of denture in such patients becomes a deciding factor between failure and success. Furthermore, increased interarch space may result in increased height of maxillary and/or mandibular dentures with corresponding increase in weight, which further compromises the retention and stability of the prosthesis. This article describes an amalgamation of Hobkirk's impression technique in a case of resorbed maxillary residual alveolar ridge with a flabby anterior segment and fabrication of hollow maxillary dentures using a “three-dimensional printed dental spacer” with a “double-flask technique.” The weight of the final prosthesis was reduced therefore contributing to improved retention and stability of the final prosthesis.
Ardisia gigantifolia ethanolic extract inhibits cell proliferation and targets cancer stem cells in gastric cancer
Authors: Le Thi Thanh , Nguyen Phu Hung , Nguyen Van Phuong , Nguyen Thy Ngoc
Published: June 2023

Objective:

To evaluate the effects of ethanol extract from Ardisia gigantifolia leaves on cell proliferation and cancer stem cell (CSC) number in gastric cancer.

Methods:

The inhibitory effect of Ardisia gigantifolia extract on the proliferation of MKN45 and MKN74 gastric cancer cells was assessed using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay. Non-adherent culture (3D) model was used to evaluate the effect of the extract on tumorsphere size and number. Moreover, the expression of CD44, ALDH, and p21 was determined by immunofluorescence analysis. Flow cytometric analysis was performed to evaluate cell cycle arrest and the expression of gastric CSC markers CD44 and ALDH. Real-time PCR analysis was also carried out to assess the effect of the extract on the expression of cell cycle-regulated genes.

Results:

Ardisia gigantifolia extract effectively inhibited cell proliferation with an IC50 of 55.7 µg/mL in MKN45 cells and 123.6 µg/mL in MKN74 cells. The extract also arrested cell cycle in the G0/G1 phase as well as significantly reduced the size and number of tumorspheres. The markedly increased expression of p21 was observed at both mRNA and protein levels in the extract-treated adherent cells and tumorspheres. In addition, Ardisia gigantifolia extract significantly reduced the number of CD44- and/or ALDH-expressing gastric CSC.

Conclusions:

The development of gastric CSC can be inhibited by the ethanol extract of Ardisia gigantifolia.
A Study of Clinical Profile of Patients with Snake Bite Attending a Tertiary Care Hospital in the North Bank of the Brahmaputra
Authors: Baruah Chitralekha , Baruah Bhaskar , Bhattacharjee Subhadeep , Hazarika Karuna
Published: June 2023

Background:

Snake bite envenomation is a neglected tropical disease which needs urgent medical attention and anti-snake venom (ASV) infusion but is often overlooked and under-reported owing to the age-old tradition of local aid by quacks, poor transportation facilities, and lack of public awareness. This leads to delays in hospitalization and causes increased morbidity and mortality. WHO’s global target is to reduce the number of snake bite deaths to half by 2030 and India needs to play an important role in achieving the target.

Aims and Objectives:

(a) To study the clinical profile of patients, 12 years of age or above, presenting with snake bites, attending OPD and Emergency in the Department of Medicine, TMCH. (b) To study the effectiveness of ASV and adverse effects following its use.

Materials and Methods:

(a) Study design—hospital based cross-sectional study. (b) Duration—1st January 2020 to 30th June 2022. (c) Number of cases—221.

Results:

Out of 221 cases, non-venomous bites and venomous bites were 88.2% and 11.7%, respectively. Out of the venomous cases, 61.5% were hemotoxic and 38.4% were neurotoxic. A total of three patients died during our study and all of these were from neurotoxic bites.

Conclusion:

Snake bite is an important rural and occupational hazard. Delay in hospitalization following snake bite creates a hindrance in timely administration of ASV leading to deleterious effects which may prove fatal. In the present study neurotoxic bites proved to be more fatal in comparison to hemotoxic bites.
Essential Thrombocytosis
Authors: Shashank Parimi Ram , Rahman Intikabur
Published: June 2023

Essential thrombocytosis is a chronic myeloproliferative disorder of unknown etiology, which is characterized by persistent megakaryocytic proliferation, resulting in markedly increased platelets in circulation. We present the case of a 40-year-old female patient, who came with complaints of excessive tiredness, infrequent tingling sensation at the tip of her fingers, and generalized body ache, and was initially detected to have extreme thrombocytosis of 1,775,000/mm3. On further evaluation, she was diagnosed with essential thrombocytosis and did not report any further deterioration throughout the follow-up period and is being maintained on low-dose aspirin.
A Cross-Sectional Study of Lipid Profile in Anemic Patients in a Tertiary Care Center
Authors: Beeravelli Sruthisri , Kinathankaraiyan Nagarajan , Manickam Rajendran
Published: June 2023

Background:

Various studies have reported a correlation (both positive and negative) between the status of anemia and lipid profile. Studies observed that the lipoproteins levels were significantly lower in anemic patients, and this reduction was proportional to the severity of anemia and not related to the type of anemia.

Objectives:

To study the lipid profile among the anemia patients and the correlation between the severity of the anemia and lipid subfractions.

Materials and Methods:

This is a cross-sectional study among 85 subjects with anemia in a Tertiary care hospital, who satisfied the eligibility criteria. After detailed history, clinical examination and blood investigations including blood counts, hemoglobin, and lipid profile were done.

Results:

The mean hemoglobin (g/dL) among the subjects was 7.86 (±2.03) g/dL ranging from 3 to 11 g/dL. Among the 85 subjects, 35 (41.18%) had dimorphic anemia followed by 21 (24.71%) had microcytic hypochromic anemia, 15 (17.65%) had normocytic hypochromic anemia, and 14 subjects (16.47%) had normocytic normochromic anemia. Body mass index was not significantly associated with the type and severity of anemia. Lipid subfractions were not associated with the type of anemia and significantly decreased with an increase in the severity of anemia.

Conclusion:

The lipid profile parameters in our study were not associated with type of anemia and significantly decreased with an increase in the severity of anemia.
A Case of NMO Presenting with Hyperthyroidism
Authors: Bansal Yukti , Patra Anil Kumar , Kalita Bipul Chandra
Published: June 2023

Neuromyelitis optica (NMO) is an autoimmune disease of central nervous system with extensive clinical presentations but based on the international consensus diagnostic criteria 2015. The horizon has broadened to a larger entity called NMOSD or NMO spectrum disorders. Nonneurological systemic autoimmune diseases especially thyroid disorders are commonly associated with NMOSD, among which Hashimoto’s thyroiditis is common, whereas not much literature is available regarding the association of Graves’ disease with NMOSD. A 38-year-old male presented with acute onset upper motor neuron quadriparesis along with features of hyperthyroidism with a prior history of sudden onset bilateral decreased vision of both eyes 3 years back. Magnetic resonance imaging (MRI) showed T2 hyperintensity involving cervicodorsal cord from C4 to D6 indicating a longitudinally extensive transverse myelitis (LETM) but brain MRI was normal. Serum antiaquaporin 4 antibody in the cell-based assay was positive. Serum thyroid stimulating hormone was very low with high free T4 and positive thyroid stimulating hormone receptor antibody and anti-thyroid peroxidase Ab. With optic neuritis, transverse myelitis (LETM), and positive antiaquaporin 4 antibody, he was diagnosed with NMO with Graves’ disease. Autoimmune thyroid diseases are associated with NMO in many studies but precise clinical and serological quantification of thyroid disorders especially Graves’ disease is still lacking. We are presenting a case of NMO with Graves’ disease who presented with symptoms of hyperthyroidism before myelitis. Our patient developed myelitis almost 3 years after having optic neuritis, but before myelitis, he was having symptoms of hyperthyroidism. Hence, patients of suspected NMO must be monitored for other nonneurological autoimmune diseases both clinically and serologically even in early stage when they are not fulfilling the diagnostic criteria.
Minimizing Lead Exposure among Children
Authors: Shrivastava Saurabh RamBihariLal , Shrivastava Prateek Saurabh
Published: June 2023

Lead is a toxic metal being employed in numerous industries across the world, and is responsible for environmental contamination and multiple adverse health effects during its processing, use, and disposal. The good thing is that all such effects are avoidable, but we are falling short in all possible dimensions. Even though various potential sources of exposure have been identified for environmental contamination or human adverse effects, lead paint is one of the most important ones. From a financial perspective, the use of these paints is associated with both direct and indirect economic costs and is immense in developing nations. Moreover, some nations have already adopted measures to reduce exposure to lead paint, but their practical implementation is lagging in most places. To conclude, lead exposure during childhood has been associated with multiple acute and chronic side effects. It is high time that international stakeholders realize the concern and prioritize it to reduce its level in the environment.
Platelet Satellitism
Authors: Agarwal Atul Kumar , Agarwal Dinesh , Deori Manoj K.
Published: June 2023

Platelet satellitism is a rare in vitro phenomenon presenting with platelets rosetting around neutrophils observed in peripheral blood smears prepared from blood samples anticoagulated with ethylenediaminetetraacetic acid (EDTA) but not with heparin sample. The subject was a 65-year-old woman presenting with pain abdomen at our hospital. As a routine investigation, complete blood count (CBC) was advised, and collection was done in EDTA vial. The sample was run in Sysmex Xs800i five-part hematology cell counter. The results of CBC were as follows: total leucocyte count: 15.59 × 103/uL; red blood cell count: 4.61 × 106/uL; hemoglobin: 12.8 g/dL; packed cell volume: 39.5%; mean corpuscular volume: 85.7fl; mean corpuscular hemoglobin (MCH): 27.8 pg; MCH concentration: 32.4 g/dL; and platelet: 26 × 103/uL. On preparation of blood smear and after staining with Leishman stain, the smear showed the formation of platelet rosette around the neutrophils. Platelet satellitism is, hence, defined as the formation of platelet rosetting or clumping around the neutrophils in sample collected in EDTA. Microscopic examination of samples collected in EDTA vial is important before commenting on platelet count.