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A Novel Flip-Filtered Orthagonal Frequency Division Multiplexing-Based Visible Light Communication System: Peak-to-Average-Power Ratio Assessment and System Performance Improvement
No full textFiltered orthogonal frequency division multiplexing (F-OFDM), employed in visible light communication (VLC) systems, has been considered a promising technique for overcoming OFDM’s large out-of-band emissions and thus reducing bandwidth efficiency. However, due to Hermitian symmetry (HS) imposition, a challenge in VLC involves increasing power consumption and doubling inverse fast Fourier transform IFFT/FFT length. This paper introduces the non-Hermitian symmetry (NHS) Flip-F-OFDM technique to enhance bandwidth efficiency, reduce the peak–average-power ratio (PAPR), and lower system complexity. Compared to the traditional HS-based Flip-F-OFDM method, the proposed method achieves around 50% reduced system complexity and prevents the PAPR from increasing. Therefore, the proposed method offers more resource-saving and power efficiency than traditional Flip-F-OFDM. Then, the proposed scheme is assessed with HS-free Flip-OFDM, asymmetrically clipped optical (ACO)-OFDM, and direct-current bias optical (DCO)-OFDM. Concerning bandwidth efficiency, the proposed method shows better spectral efficiency than HS-free Flip-OFDM, ACO-OFDM, and DCO-OFDM
Development and Evaluation of Drone Based Spraying System for Precision Agriculture Application
No full textUnmanned aerial vehicles (UAVs), also known as drones, are increasingly used for various purposes such as photography, surveillance, mapping, inspection, and agriculture. This research specifically focuses on agricultural drones, which have the potential to address challenges encountered by farmers, ultimately positively affecting crop yields. Their ability to apply pesticides accurately and autonomously, without direct human involvement, is crucial for modern farming practices. This study aims to design and simulate a quadcopter specifically tailored for pesticide spraying. The design process involves careful selection of components and simulation using both SolidWorks and MATLAB Simulink. In SolidWorks, design the frame and components, while MATLAB Simulink is used to simulate trajectory tracking using PID controllers. The key finding is the integration of a multispectral camera to capture images and analyze data using Pix4Dfields and Agremo software. This analysis helps pinpoint specific areas requiring treatment, thereby minimizing pesticide and water usage while maximizing profitability. By targeting exact locations in the field based on data analysis, this approach improves efficiency. The research focuses on evaluating the quadcopter’s performance and trajectory accuracy, offering valuable insights into its potential agricultural impact, and assisting farmers in enhancing their profits through improved spraying techniques and resource management
Hydrogels from Protein-Polymer Conjugates: A Pathway to Next-Generation Biomaterials
No full textHybrid hydrogels from protein–polymer conjugates are biomaterials formed via the chemical bonding of a protein molecule with a polymer molecule. Protein–polymer conjugates offer a variety of biological properties by combining the mechanical strength of polymers and the bioactive functionality of proteins. These properties allow these conjugates to be used as biocompatible components in biomedical applications. Protein–polymer conjugation is a vital bioengineering strategy in many fields, such as drug delivery, tissue engineering, and cancer therapy. Protein–polymer conjugations aim to create materials with new and unique properties by combining the properties of different molecular components. There are various ways of creating protein–polymer conjugates. PEGylation is one of the most common conjugation techniques where a protein is conjugated with Polyethylene Glycol. However, some limitations of PEGylation (like polydispersity and low biodegradability) have prompted researchers to devise novel synthesis techniques like PEGylation, where synthetic polypeptides are used as the polymer component. This review will illustrate the properties of protein–polymer conjugates, their synthesis methods, and their various biomedical applications
Intrusion detection system in wireless sensor networks using machine learning
No full textCurrent industrial control systems are increasingly integrating with corporate Internet technology networks in order to fully utilize the abundant resources available on the Internet. The growing connection between industrial control systems and the internet has made them a desirable choice. Industrial control systems are in need of significant protection due to being a common target for a range of cyber-attacks. The use of the Internet of Things is currently increasing across industries due to its efficiency, and the Internet of Things is facing a security challenge. This document gives an overview of the intrusion detection system and the methods of the intrusion detection system. The purpose of this document is to examine intrusion detection methods and present the best method based on studies. Experimental results show that this system uses a combination of machine learning methods for high performance
How uncertainty affects firm performance in the textile and clothing industry: a comparison of European manufacturing and retail firms
No full textWe explore the impact of economic policy uncertainty (EPU) on firm performance in the European textile and clothing industry. Using a dataset of 2,129 firms from 11 European countries over the period 2013–2023, we employ system GMM estimation to investigate the effects of both domestic and global policy uncertainty on manufacturing and retail firms. The results suggest that both forms of uncertainty have a negative impact on firm performance, with domestic EPU mainly affecting retail firms and global EPU affecting manufacturing firms. We also find evidence of a nonlinear, U-shaped relationship between domestic uncertainty and firm performance, suggesting that firms may adapt to uncertainty at elevated levels. In addition, the findings highlight the role of working capital as an important buffer against uncertainty, particularly for retail firms. Overall, the study provides new insights into sector-specific vulnerabilities and suggests ways for firms to strengthen their financial resilience in an increasingly unpredictable economic environment
Secure edge-based smart grid communication using lightweight authentication modeling with autoencoders and real-world data
No full textArticle number : 110The growing use of edge computing in intelligent grids presents security issues as a result of the limited processing capabilities of edge devices and the intensifying complexities of cyberattacks. The conventional authentication schemes based on cryptographic protocols have excessive computational overhead, rendering them inappropriate for real-time grid communication. This paper presents a light-weight authentication scheme based on a five-layer deep autoencoder for anomaly-based authentication, facilitating secure and efficient communication in resource-limited edge-based smart grids. Temporal sequencing and feature normalization are utilized to optimize the model to enhance detection accuracy while minimizing computational complexity. Moreover, an adaptive thresholding scheme is incorporated to increase the robustness of the model against changing cyber-attacks, maintaining high reliability in dynamic smart grid scenarios. Experimental verification on the ICS dataset shows that the proposed framework attains 99.37% detection accuracy, actual rejection rate of 99.4%, and false rejection rate as low as 0.50%, outperforming the state-of-the-art solutions. Moreover, the framework facilitates real-time authentication with latency of ≤ 2 ms and ultra-low energy expenditure (0.015 W per authentication decision), being 30% faster and 50% more power-efficient compared to state-of-the-art solutions. The model performs at a high level even under heavy communication loads and demonstrated its scalability to 50,000 + edge devices. These findings set a new standard in smart grid security, delivering a low-latency, scalable, and energy-efficient authentication solution for deployment in real-world scenarios. The system is tailored to meet Middle East and Turkey regional cybersecurity challenges, tackling infrastructure asymmetry and environmental limitations in smart grid systems
O Escore Prognóstico de Nápoles Prevê Fibrilação Atrial de Início Recente em Pacientes com Infarto do Miocárdio com Supradesnivelamento do Segmento ST Submetidos à Angioplastia Primária
No full textArticle number : e20240671Background: New-onset atrial fibrillation (NOAF) is a typical complication in patients with ST-segment elevated myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (pPCI). Previous studies have investigated inflammation as a NOAF predictor. The Naples prognostic score (NPS) is a novel marker of inflammation and nutritional status. Objective: The objective of this study was to evaluate the predictive power of the NPS for NOAF. Methods: This study enrolled 1537 consecutive STEMI who underwent pPCI. The patients who presented NOAF during hospital admission and those who remained in sinus rhythm (RSR) were compared in terms of baseline characteristics. Univariate and multivariate analyses were carried out to identify variables predicting NOAF development, and p< 0.05 was considered statistically significant. Results: NOAF was detected in 7.74% (n: 119) of the participants. The mean age (67.03±13.48 vs 57.84±11.31; p <0.001) and NPS (2.53±1.17 vs 2.25±1.10, p=0.008) were significantly higher in the NOAF group. Multivariate analysis revealed age (Odds ratio [OR]: 1.045 for a year, 95% confidence interval [CI]: 1.019–1.071, p=0.001), NPS (OR: 1.645, 95% CI: 0.984–2.748, p=0.037) and left atrial dimensions (OR: 2.542 for cm, 95% CI: 1.488–4.342, p=0.001) as independent predictors of NOAF. Conclusions: The NPS was an independent predictor of NOAF in STEMI patients, in addition to classical factors such as age and left atrial dimensions. This score, mostly related to an inflammatory burden, may help to predict NOAF incidence and select better potential therapies aimed at abating inflammation after myocardial infarction
Cooperation
No full textCooperation is generally defined as a policy coordination process in which various entities such as states, non-governmental organizations and international organizations modify their behaviour to satisfy existing or expected preferences of other involved parties in order to acquire mutual benefits. Cooperation has always been a central concept for international relations and has been discussed within various theoretical frameworks since the establishment of the International Relations (IR) discipline. This entry elucidates the concept of cooperation and its significance in IR. By acknowledging the historical context, the entry evaluates the outlook of the major IR theories on cooperation as well as its possibilities and restrictions. It concludes that the focus of the research on cooperation has shifted from analysing the possibilities of cooperation to distinguishing particular forms of cooperation and resolving specific cooperation problems