Many Areas Of Engineering Research Articles

Extraction and Physicochemical Characterization of Chitin from Galeodes araneoides (Pallas, 1772) (Arachnida: Solifugae)

: Chitin is a biomaterial which has a high potential of use in many areas of technology. It is found as a structural material in the outer skeletons of arthropods, the cell walls of mushrooms, and the shells of marine invertebrates. Chitin is the most abundant biopolymer in nature after cellulose and contains nitrogen in its structure. In recent years, apart from traditional chitin sources, insects, arachnids, coral/crustacean eggs and even bat guano have been reported as alternative chitin sources. In this study, chitin was first extracted from external skeleton of a solifugids species, Galeodes araneoides (Pallas, 1772) and the isolated chitin was characterized by SEM, FTIR, XRD, and TGA. The obtained chitin has been found to have high thermal stability, nanofiber and nanoporous surface, and alpha form and it is suggested that it can be an alternative chitin source.

A review on modern prosthodontic practice using laser.

Lasers are a very appealing technology in many areas of dentistry because of their minimally invasive nature, quick tissue interaction & response, and ability to heal. Numerous investigations on the possible uses of lasers in dentistry have been carried out since Maiman developed the ruby laser in 1960. Numerous applications such as quick prototyping and computer-aided design, and the study of occlusion in complete denture using three-dimensional laser scanning has been used to develop dentures. Its uses are numerous from fixed prosthodontics to dentinal hypersensitivity treatment to surface treatment of base metal alloys. These days, it even encompasses maxillofacial prosthodontics and dental implantology. Hence, it is of interest to review the use of lasers in clinical prosthodontics.

A new generalized beta function associated with statistical distribution and fractional kinetic equation

Several authors have extensively investigated beta function, hypergeometric function and confluent hypergeometric function, their extensions and generalizations due to their several application in many areas of engineering, probability theory and science. The main purpose of this paper is to present a new generalization of extended beta function, hypergeometric function and confluent hypergeometric function with the help of m-parameter Mittag-Leffler function, as well as examine some important properties like integral representations, differential formula and summation formulas. We also examine generalized Caputo fractional derivative operator with the help of m-parameter Mittag-Leffler function with associated properties using the generalized beta function. We define a new beta distribution involving the new generalized beta function. The mean, variance, coefficient of variance, moment generating function and characteristic function and cumulative distribution are derived. Further, we derive the solution of fractional Kinetic equation involving generalized hypergeometric function.

Performance Estimation of a Medium-Resolution Earth Observation Sensor Using Nanosatellite Replica.

In many areas of engineering, the design of a new system usually involves estimating performance-related parameters from early stages of the project to determine whether a given solution will be compliant with the defined requirements. This aspect is particularly relevant during the design of satellite payloads, where the target environment is not easily accessible in most cases. In the context of Earth observation sensors, this problem has been typically solved with the help of a set of complex pseudo-empirical models and/or expensive laboratory equipment. This paper describes a more practical approach: the illumination conditions measured by an in-orbit payload are recreated on ground with the help of a replica of the same payload so the performance of another Earth observation sensor in development can be evaluated. The proposed method is specially relevant in the context of small satellites, as the possibility of having extra units devoted to these tasks becomes greater as costs are reduced. The results obtained using this method in an actual space mission are presented in this paper, giving valuable information that will help in further stages of the project.

Analysis of the retraining strategies for multi-label text message classification in call/contact center systems

Today, in many areas of technology, we can come across applications of various artificial intelligence methods. They usually involve models trained on some specific pool of learning data. Sometimes, however, the data analyzed by these solutions can change its nature over time. This usually results in a decrease in classification efficiency. In such a case, the use of techniques to retrain the originally trained reference models should be considered. One of the industries where the nature of data changes quite dynamically over time is the broadly defined call/contact center systems. An example of a module that is often found in this type of system and that, due to frequently changing marketing campaigns, requires the use of learning techniques is the automatic classification of text data. The paper describes the process of retraining the original reference models used in a multi-label text message classification method dedicated directly to call/contact center systems applications. In order to carry out the retraining process, Polish-language data from the actual archives of a large commercial contact center system and English-language data extracted from a publicly available database were used. The study was conducted for models based on artificial neural networks and bidirectional encoder representations from transformer type models. In addition, two different retraining strategies were studied, the results of which were compared with data obtained from the operation of reference models. As a result of the research work, an improvement of up to 5% in classification efficiency, as described by the metric Emotica was obtained, which means that proper integration of the retraining process brings tangible benefits to the solution tested in the article. Thus, it can also benefit the solutions used in business.

Innovative Composite Material with Pseudo-Porous Structure

This article will discuss a new generation of composite material, patented by scientist Nadezhda Iushkina and which is a new technology in many areas of application. The article will reveal the main characteristics of the material as well as ways of its use.

Pre-prosthetic atraumatic laser-assisted mandibular rehabilitation: Er,Cr:YSGG 2780 nm for alveoloplasty and mucocele removal. A case report

Lasers are a popular technology in many areas of dentistry due to their low invasiveness, quick tissue response, and rapid healing time. Mucoceles develop from minor salivary glands, whereas bony exostosis is a prosthodontic challenge that prevents optimal prosthetic management. Scarring, pain, and discomfort are common drawbacks of traditional surgical approaches, which are followed by prolonged postoperative healing. Laser-assisted mandibular rehabilitation is a promising approach with predictable results. The patient complained of severe pain during denture fabrication, as well as a small, painless swelling on the inner aspect of the lower lip. The patient was able to receive the planned complete dentures after undergoing atraumatic laser-assisted removal of mucocele and bone exostosis with an Er,Cr:YSGG (Erbium, chromium-doped, yttrium, scandium, gallium, and garnet) laser treatment at 2780 nm. Both procedures were completed quickly, and there were no postoperative complications to report. Blanching overlying both lesions quickly faded after healing and was replaced by a healthy pink mucosal color; both lesions were monitored until complete healing. The Er,Cr:YSGG effectively ablated and removed both soft and hard tissue lesions with minimal bleeding and pain.

Pre-prosthetic atraumatic laser-assisted mandibular rehabilitation: Er,Cr:YSGG 2780 nm for alveoloplasty and mucocele removal. A case report

Lasers are a popular technology in many areas of dentistry due to their low invasiveness, quick tissue response, and rapid healing time. Mucoceles develop from minor salivary glands, whereas bony exostosis is a prosthodontic challenge that prevents optimal prosthetic management. Scarring, pain, and discomfort are common drawbacks of traditional surgical approaches, which are followed by prolonged postoperative healing. Laser-assisted mandibular rehabilitation is a promising approach with predictable results. The patient complained of severe pain during denture fabrication, as well as a small, painless swelling on the inner aspect of the lower lip. The patient was able to receive the planned complete dentures after undergoing atraumatic laser-assisted removal of mucocele and bone exostosis with an Er,Cr:YSGG (Erbium, chromium-doped, yttrium, scandium, gallium, and garnet) laser treatment at 2780 nm. Both procedures were completed quickly, and there were no postoperative complications to report. Blanching overlying both lesions quickly faded after healing and was replaced by a healthy pink mucosal color; both lesions were monitored until complete healing. The Er,Cr:YSGG effectively ablated and removed both soft and hard tissue lesions with minimal bleeding and pain.

Parents’ Assessment of Their Children’s Use of Technology

IntroductionThe use of technology in many areas of daily life is widespread among both children and adults. Excessive and inappropriate use of technological aids causes significant problems in physical, psychomotor, psychological and social stages of development, especially in childhood. One of the reasons for some problems that arise in adulthood, such as communication problems, anxiety disorders, obesity, musculoskeletal disorders and tendency to violence is the excessive and inappropriate use of technology in childhood. For this reason, it is of great importance to complete the developmental stages in childhood in a healthy way.ObjectivesThe aim of this study was to qualitatively assess the technology use habits of 48-72 month old preschool children and their parents.MethodsThe study is a qualitative research conducted among the parents of children in Eskişehir and Bolu between March and June 2023. A semi-structured form was used for the personal interviews with the 25 parents who constituted the study group. The interviews were recorded. The audio recordings were then transcribed and a thematic content analysis was conducted. The main themes of the interviews concerned the habits of parents’ and children’s in the use of technology at home, the content used on technological devices and how it is controlled, and the arrangements for technology use at home.ResultsIn the interviews, parents reported that when they needed to use technological devices, they most often chose a time and place when the children were not present or asleep. When children spent more time at home, this was the most common reason for increased technology use, while the most common reason for decreased use was that children spent more time outside the home. Most parents limited the amount of time their children’s daily technology using time. It was found that children generally complied with these restrictions, and when they did not, they often expressed themselves with reactions such as sulking/angry/crying.ConclusionsThis study emphasizes that the most important factor determining children’s attitudes towards technology use is their parents’ attitudes towards technology use In order for children to develop a positive attitude towards technology use, it can be beneficial for parents to regulate and control their children’s technology use as well as their own.Disclosure of InterestNone Declared

VpROM: a novel variational autoencoder-boosted reduced order model for the treatment of parametric dependencies in nonlinear systems

Reduced Order Models (ROMs) are of considerable importance in many areas of engineering in which computational time presents difficulties. Established approaches employ projection-based reduction, such as Proper Orthogonal Decomposition. The limitation of the linear nature of such operators is typically tackled via a library of local reduction subspaces, which requires the assembly of numerous local ROMs to address parametric dependencies. Our work attempts to define a more generalisable mapping between parametric inputs and reduced bases for the purpose of generative modeling. We propose the use of Variational Autoencoders (VAEs) in place of the typically utilised clustering or interpolation operations, for inferring the fundamental vectors, termed as modes, which approximate the manifold of the model response for any and each parametric input state. The derived ROM still relies on projection bases, built on the basis of full-order model simulations, thus retaining the imprinted physical connotation. However, it additionally exploits a matrix of coefficients that relates each local sample response and dynamics to the global phenomena across the parametric input domain. The VAE scheme is utilised for approximating these coefficients for any input state. This coupling leads to a high-precision low-order representation, which is particularly suited for problems where model dependencies or excitation traits cause the dynamic behavior to span multiple response regimes. Moreover, the probabilistic treatment of the VAE representation allows for uncertainty quantification on the reduction bases, which may then be propagated to the ROM response. The performance of the proposed approach is validated on an open-source simulation benchmark featuring hysteresis and multi-parametric dependencies, and on a large-scale wind turbine tower characterised by nonlinear material behavior and model uncertainty.

Key Distribution and Authentication Protocols in Wireless Sensor Networks: A Survey

We use sensor technologies in many areas of everyday life. We use sensors to check and study various phenomena and to improve our lives. Hence, the sensors are used in medicine, industry, sports, and many other aspects of everyday life. Interconnected sensors and other wireless devices and servers form Wireless Sensor Networks. During communication between the nodes of such networks, we often send private and sensitive data. These data should be properly secured. Securing communication in a Wireless Sensor Network mainly affects the reconciliation and distribution of session keys and authentication. Specially designed protocols must protect both methods. In turn, the protocols may be exposed to dishonest users of such networks and thus exposed to various attacks (for example, replay attacks and smart card stolen attacks). This article surveys the existing session key negotiation, distribution, and authentication protocols. We will explain the security problems and threats to which the sensor networks are exposed. We will discuss the security levels implemented by the protocols currently used in sensor networks. We will analyze the challenges and requirements faced by the newly designed protocols.

Measurement, Modeling, and Analysis of the Dynamic Properties of Resilient Elements Used for Vibration Isolation

Abstract Resilient elements are widely applied for vibration and noise control in many areas of engineering. Their complex dynamic stiffness gives fundamental information to describe their dynamic performance and is required for predicting structure-borne sound and vibration using dynamic modeling. Many laboratory measurement methods have been developed to determine the dynamic properties of resilient elements. This paper presents a review of recent developments in the measurement methods from the perspective of force–displacement relations of the resilient element assembly rather than of their material properties. To provide context, the review begins with an introduction to modeling methods for resilient elements, especially for rubber and rubber-like isolators, and three standardized measurement methods are introduced. Recent developments are then discussed including methods to extend the frequency range, which are mainly developments of the indirect method. Mobility methods, modal-based methods, recent active frequency-based substructuring (FBS), and inverse substructuring (IS) methods to study the dynamic properties of resilient elements are also described. Laboratory test rigs and the corresponding identification methods are outlined. Methods to evaluate nonlinear dynamic properties of resilient elements by laboratory measurements are also discussed. Finally, the review is concluded by discussing the advantages and limitations of the existing methods and giving suggestions for future research.

A Review on Traditional and Modern Methods for the Synthesis of Aromatic Azo Compounds

Abstract: Aromatic azo compounds are “derivatives of diazene/diimide”, wherein the two hydrogens are substituted by phenyl groups. Azo compounds are very important universal scaffolds that show multiple applications in many areas of science, mainly chemical industries, where they are used in the synthesis of organic dyes, pigments, food additives, indicators, etc. They also remarkably exhibit various potential applications in the fields of pharmaceuticals, electronics, optics, etc., because of their fascinating photophysical properties. Moreover, several azo compounds have been strongly utilized as chemosensors, diagnostic probes, radical initiators, nanotubes, and building blocks of various polymers as well as natural products. This interesting and immense importance of the azo compounds has attracted the attention of researchers to establish novel synthetic routes to synthesize these important scaffolds. In organic chemistry, azo compounds can be synthesized by various methods utilizing coupling reactions with the aid of a catalyst or sometimes in the absence of it. The main purpose of writing this review was to provide a summary of the synthesis of both symmetric and asymmetric azobenzenes via various traditional and recently developed oxidative aza-coupling reactions.

An ANN-based Hong-Lagrange algorithm (ANN-based HLA) for auto design-based building application (ABBA) with prestressed precast piperack frame

ABSTRACT Building optimization using traditional approaches based on explicit objective functions is difficult because of large numbers of variables and constraints. Many studies, thus, developed derivative-free optimizations using evolutionary programming, particle swarm methods, swarm intelligence, etc. Applications of artificial neural networks (ANNs) in frame designs are not common, although ANN is an evolutionary technology in many areas. This study presents novel holistic designs and optimizations of prestressed multi-story frames in general and piperack frames in particular, using the ANN-based Hong-Lagrange Algorithm. The proposed method provides optimized designs in terms of multiple objective functions such as costs, CO2 emissions, weights, and energy consumptions. A software is developed based on MATLAB codes for generating big datasets following American standards. A big data of 120,000 samples is used to train ANNs, formulating objective and constraint functions of 38 input and 69 output parameters. Designs minimizing multiple objective functions are performed by applying sequential quadratic programming to ANN-based functions constrained by equalities and inequalities imposed by architectural and code requirements. Examples show reductions up to 31.81%, 38.63%, 5.06%, and 37.36% in costs, CO2 emissions, weights, and energy consumption, respectively, compared with the minima of those identified from 340,000 samples.

An investigation into the interaction between a nonlinear resonance and a fixed anti-resonance in a harmonically excited system

The study of linear mechanical structures with discrete nonlinear attachments is a widespread field in structural dynamics as it is important in many areas of engineering. A common type of nonlinearity is a hardening spring, which can be described by a cubic polynomial representing the force-deflection relationship. The frequency response of a system consisting of a hardening spring and a mass is characterized by an amplitude-dependent resonance frequency, that increases as the displacement of the mass increases. The way in which the resonance of a nonlinear attachment interacts with the resonance of a linear host structure has already been discussed in the literature, however little attention has been paid to the interaction of the nonlinear resonance with a fixed anti-resonance of the host structure. This paper aims to fill this gap by addressing the physical aspects of the interaction between an anti-resonance and a resonance due to a nonlinear resonant attachment. A two-degrees-of-freedom system representing a general structure with two modes of vibration is used as a host structure to which a nonlinear resonant device is attached. The host structure has a fixed anti-resonance prior to the nonlinear device being attached to the structure, and the influence of this device on the anti-resonance is investigated. This is achieved by using the harmonic balance method and a numerical continuation algorithm. In the study, it was found that the anti-resonance interacts with the nonlinear resonance, where some of the peaks bend toward higher frequencies because of the hardening stiffness. Further increasing the nonlinearity, results in an isola being formed inside the main frequency response curve. When the motion is extremely high, quasi-periodic or chaotic-like responses are observed in specific frequency regions.

A moment-of-fluid method for resolving filamentary structures using a symmetric multi-material approach

Multiphase flows have implications in many areas of engineering. The moment-of-fluid (MOF) method is an interface capturing method using both volume fraction and centroid within a cell for interface reconstruction. A symmetric approach to reconstruct thin structures is presented. Also called filaments, these subcell characteristics involve multi-material reconstruction. In addition, a new optimisation algorithm is presented using a bisection method without any necessary initial condition. Using a Lagrangian approach for dynamic cases, no restrictions are imposed on timestep. The new method is validated using several benchmark cases that have been studied extensively in the literature. A near quadratic order of convergence and high accuracy is achieved while maintaining an acceptable runtime.

Applications of the Laplace variational iteration method to fractional heat like equations

The importance of differential equations of integer order and fractional order can be seen in many areas of engineering and applied sciences. The present work involves fractional order heat equations that arise in numerous applications of engineering and aims to find series solutions by the Laplace variational iteration method (LVIM). The method combines the Laplace transform and the variational iteration method. To show the efficiency and validity of LVIM, we have exemplarily considered 1-D, 2-D, and 3-D fractional heat equations and solve them by LVIM. Exact solutions are gained in expressions of the Mittag-Leffler function. The results are also explored through graphs and charts.

The Problem of Digital Disability in E-Municipality: A Study on Metropolitan Municipalities

The distinctive feature of the digital society is that it can practically use information and communication technologies in many areas of life, and the digital literacy rate is relatively high. The fact that most of the bureaucratic processes in e-government and e-municipality are transferred to virtual environments increases the importance of such topics as digital literacy and digital disability. One of the basic skills of the digital society is the relatively high rate of digital literacy and the increased ability of the members to use information and communication technologies. For this reason, the absence of digital disabilities and the design of web tools for individuals with disabilities are significant in digital accessibility. Suppose web tools are not designed for people with disabilities. In that case, it is inevitable that a new form of disability, which is unique to the digital society and called "digital disability," will emerge. The primary purpose of this research is to examine the web pages of Metropolitan Municipalities in Turkey according to digital disability criteria. For this purpose, the web pages of 30 Metropolitan Municipalities were analyzed in terms of digital accessibility, digital disability, and access performance. Within the framework of the research problem, sampling was determined according to the sampling method. Descriptive statistics and content analysis methods were used to analyze the data collected from the sample. The research findings show that the web pages of Metropolitan Municipalities have some inadequacies in digital accessibility and performance indicators.

Reconstruction of the rotor output signal of a direct current motor using numerical approximation

In many areas of technology and research, who study behavior process have increasingly relied on mathematical models. Most of the time the mathematical model is used, representing the important aspect of a dynamic system. Sometimes the mathematical model does not have an appropriate structure and it can be loss the relevant information, nevertheless output signal characterization based on an input signal using laboratory measurements in real time can keep the relevant information, which it is not contemplated in the mathematical model because they involve losses or disturbances. In this work the speed of the rotor magnetic field with respect to the stator magnetic field for a dc motor in real time is showing, the data will be processed and a polynomial approximation is depicting and can effectively trigger with the mathematical model. Finally, a stability analysis is present, it shows the regions or system stability points (pre-fault, fault and post-fault), and the direction from which stability is reached through time.

Telemedical consultations on oncology in the Republic of Bashkortostan

BACKGROUND: The COVID-19 worldwide pandemic enabled the expanded use of telemedical technologies in many areas of medicine. Remote consultations helped conserve medical resources and reduce the risk of spreading COVID-19 while preserving patients access to medical care. In addition, telemedicine played a role in caring for patients who live in remote regions. Other benefits include savings in transportation costs and travel time both for patients and caregivers. Telemedicine, together with remote health monitoring technologies, has high potential in developing a preventive healthcare system and increasing the accessibility of medical care and meets current challenges by improving healthcare quality and providing an individual approach to patients. In 2020, the Center of Telemedicine was created in the Republican Clinical Oncological Dispensary (RCOD) to organize and improve telemedical assistance to the population of the Republic of Bashkortostan in the oncology profile.
 AIM: To analyze telemedical consultations (TMCs) on oncology in the Republic of Bashkortostan for the period of 20202022.
 METHODS: Quantitative count and comparison of the TMCs conducted by the RCOD of the Ministry of Health of the Republic of Bashkortostan in 20202022 and sent to the National Medical Research Center (NMRC) were performed. The work on referrals to the NMRC for revision of examination results (computer tomography, magnetic resonance imaging, positron emission tomography/computed tomography, and histological examinations), obtaining a second opinion, and determining treatment tactics was organized.
 RESULTS: In 2020, 32,076 TMCs were conducted, while 225 TMCs were performed with the NMRC. In 2021, the RCOD conducted 52,139 TMCs (a 62% increase compared to 2020), whereas 473 TMCs took place in the NMRC (a 110% increase compared to 2020). During the 12 months of 2022, 57,456 TMCs were performed by RCOD staff (a 10% increase over the previous year), and 672 TMCs were conducted with the NMRC (a 42% increase compared to 2021). For feedback from referring medical organizations and monitoring and evaluating the quality of regional TMCs, conference calls were held with the Ministry of Health of the Republic of Bashkortostan, chief physicians, and oncologists of the Republic of Bashkortostan.
 CONCLUSIONS: TMCs allow for the rapid exchange of medical information, thereby reducing the time of diagnosis and timely prescription of treatment, the implementation of timely routing of patients and improving the quality and availability of medical care in the oncology profile in the Republic of Bashkortostan. The annual increase in the number of TMCs is due to the growing need for this type of specialized medical care in this profile.