Renewable energy sources like wind energy are copiously available without any limitation. Wind turbines are used to tap the potential of wind energy, which is available in millions of MW. Reliability ...of wind turbine is critical to extract this maximum amount of energy from the wind. We reviewed different techniques, methodologies and algorithms developed to monitor the performance of wind turbine as well as for an early fault detection to keep away the wind turbines from catastrophic conditions due to sudden breakdowns. To keep the wind turbine in operation, implementation of condition monitoring system (CMS) and fault detection system (FDS) is paramount and for this purpose ample knowledge of these two types of systems is mandatory. So, an attempt has been made in this direction to review maximum approaches related to CMS and FDS in this piece of writing.
Wind energy is abundantly available both onshore and offshore. As a response to the present climate crisis focus on wind energy is increasing due to its renewable and environmentally friendly ...characteristics. Due to social and political reasons the trend has been shifted largely from onshore to offshore wind farms. Offshore wind energy production faces a wide range of new challenges in design, development, manufacturing, installation, and maintenance and operation. The need, objectives, method, benefits, and application of a proposed reliability and maintainability database are identified in this paper. In the offshore oil and gas industry the OREDA concept for data collection has been running for more than 25 years. Therefore it will be briefly described what is considered to be the state of the art in this industry when it comes to data collection. Potential challenges and issues pertaining to the reliability and maintainability data collection of offshore wind turbines are outlined and categorized. The architecture of the proposed database is illustrated. The main building blocks of the database are briefly described and their possible effects on the reliability and maintainability of offshore wind turbines are highlighted. It is expected that the realization of the proposed database will open a new vista of knowledge in understanding the real behavior of offshore wind turbines in the marine environment. Another expectation is the benefits it will bring to the technological areas ranging from design to operation.
► The database will act as a tool to measure the performance in terms of power output. ► The database will give detail information to enhance the reliability levels. ► Specific challenges are covering the technical aspects. ► General challenges are related to the management of the database. ► Outline of the database has been given with possible inputs and outputs.
Background
Multiple sclerosis (MS) is a chronic immune‐mediated disorder characterized by the degradation of the myelin sheath in the central nervous system. Research indicates that individuals with ...MS exhibit a higher susceptibility to stroke compared to the general population. This association is rooted in shared underlying mechanisms, specifically involving neuroinflammatory processes.
Methodology
We performed an extensive search on PubMed, MEDLINE, Embase, Scopus, and Google Scholar using specific terms. The search terms included variations of “multiple sclerosis,” “stroke,” “cerebrovascular disease,” “vascular risk factors,” “disease‐modifying therapies,” and “neuroinflammation.” The search was limited to articles published from January 1, 2000, up to 31 May, 2023.
Results and Discussion
Stroke, a global health burden characterized by significant mortality and adult disability, underscores the critical importance of understanding the link between MS and stroke. Despite a growing body of research establishing an elevated risk of stroke in MS patients, notable information gaps persist. Limited prospective multicenter studies on stroke incidence in MS patients contribute to an incomplete understanding of the precise relationship between these two conditions.
Conclusion
In conclusion, this review underscores the critical need for a thorough understanding of the complex relationship between MS and stroke. The identified risk factors and the influence of MS DMTs on stroke risk necessitate further investigation to inform evidence‐based preventive and therapeutic strategies. Bridging the existing information gaps through prospective multicenter studies is imperative for a comprehensive understanding of this association. The development of targeted diagnostic and therapeutic approaches for acute stroke risk in MS patients is paramount to mitigate the impact of these debilitating conditions. Ultimately, this review serves as a foundation for future efforts to enhance preventative measures and therapeutic interventions, thereby improving the overall quality of life for individuals with MS susceptible to strokes.
A condition monitoring system (CMS) plays a critical role in tapping the maximum potential of wind energy through wind turbine by minimizing the downtime. It has been proved that the CMS-based ...maintenance, compared to scheduled and corrective maintenance, is more suitable in many aspects with few disadvantages. The cost of CMS design and installation is substantial in comparison to other maintenance approaches but in the longer run CMS provides benefits surpassing the costs. There are such important parameters as the identification of most sensitive, less sensitive components, replacement costs accompanied with certain components that should be taken into consideration when designing the CMS. In this paper, we have made an attempt to evaluate the viability of CMS, and important parameters in its design, system architecture and installation. The sole purpose is to highlight the overwhelming role of CMS as a better and viable option for increasing the production rate and lowering the downtime in the wind energy converter.
In today’s digital landscape, content delivery networks (CDNs) play a pivotal role in ensuring rapid and seamless access to online content across the globe. By strategically deploying a network of ...edge servers in close proximity to users, CDNs optimize the delivery of digital content. One key mechanism involves caching frequently requested content at these edge servers, which not only alleviates the load on the source CDN server but also enhances the overall user experience. However, the exponential growth in user demands has led to increased network congestion, subsequently reducing the cache hit ratio within CDNs. To address this reduction, this paper presents an innovative approach for efficient cache replacement in a dynamic caching environment while maximizing the cache hit ratio via a cooperative cache replacement policy based on reinforcement learning. This paper presents an innovative approach to enhance the performance of CDNs through an advanced cache replacement policy based on reinforcement learning. The proposed system model depicts a mesh network of CDNs, with edge servers catering to user requests, and a main source CDN server. The cache replacement problem is initially modeled as a Markov decision process, and it is extended to a multi-agent reinforcement learning problem. We propose a cooperative cache replacement algorithm based on a multi-agent deep-Q network (MADQN), where the edge servers cooperatively learn to efficiently replace the cached content to maximize the cache hit ratio. Experimental results are presented to validate the performance of our proposed approach. Notably, our MADQN policy exhibits superior cache hit ratios and lower average delays compared to traditional caching policies.
Directional antennas offer many potential advantages for wireless networks such as increased network capacity, extended transmission range and reduced energy consumption. Exploiting these advantages ...requires new protocols and mechanisms at various communication layers to intelligently control the directional antenna system. With directional antennas, many trivial mechanisms, such as neighbor discovery, become challenging since communicating parties must agree on where and when to point their directional beams to communicate. In this paper, we propose a fully directional neighbor discovery protocol called Sectored-Antenna Neighbor Discovery (SAND) protocol. SAND is designed for sectored-antennas, a low-cost and simple realization of directional antennas, that utilize multiple limited beamwidth antennas. Unlike many proposed directional neighbor discovery protocols, SAND depends neither on omnidirectional antennas nor on time synchronization. SAND performs neighbor discovery in a serialized fashion allowing individual nodes to discover all potential neighbors within a predetermined time. SAND guarantees the discovery of the best sector combination at both ends of a link, resulting in more robust and higher quality links between nodes. Finally, SAND reliably gathers the neighborhood information in a centralized location, if needed, to be used by centralized networking protocols. The effectiveness of SAND has been assessed via simulation studies and real hardware implementation.
In this paper, we study some of new types of continuous functions called soft b*−continuous functions and define soft b*−irresolute and discussed their relations with existing soft continuous and ...other weaker forms of soft continuous functions and some related properties are discussed. Also, we study soft b*−irresolute and soft b*−openmap and b*−closedmap and the relationships between them are discuss. We hope that the findings in this work will help researcher enhance and promote the further study on soft topological spaces to carry out a general framework for their applications in separation axioms, connectedness.
An area-efficient CMOS impulse radio ultra-wideband (IR-UWB) transmitter capable of generating variable orders of Gaussian pulses is presented. The core of the pulse generator is constructed using ...the cascade connection of RC differentiator networks separated by tunable amplifiers. Tuning the bias current of the amplifier using a voltage-controlled current-source allows for generation of varying orders of Gaussian pulses, which in turn allows for controlling the power and spectral mask of transmitted signals. Fabricated in a TSMC 90 nm digital CMOS process, the measurement shows that the fully integrated transmitter can generate fifth- to sixth-order Gaussian pulses. The core transmitter consumes 10.0–12.0 mW at 200 MHz pulse repeating frequency and occupies a chip area of 0.008 mm2 only.
The screening of plant extracts for natural products and antimicrobial activity has revealed the potential of higher plants as a source of new anti-infective agents. In the current study, the ...antibacterial activity of methanol extract of
leaves was tested against four bacteria species: two Gram-positive bacteria (
and
) and two Gram-negative bacteria (
and
). The Well diffusion method was used to assess the antibacterial activity of the plant extract. The results showed that the methanolic extract of
leaves was more effective against Gram-positive bacteria, with an inhibition rate of 18.28 mm, as measured by the spectrum of antimicrobial activity against
bacteria, where the zone of inhibition ranged between (24.7- 12.7) mm and (20-13.3) mm against
, when compared to Gram-negative bacteria with a mean inhibition rate of 14.28 mm and indicated by zones of inhibition ranging between (18.7 and 11.3 mm) against
and (16.3-9.3 mm) against
at concentrations of 10%-2.5% since the mean of inhibition increases with increasing concentration of the extract. This suggests that this plant extract could be used for the treatment of a variety of diseases caused by these pathogens. The presence of alkaloids, flavonoids, saponins, sterols/terpenes, and tannins in the leaf was validated by phytochemical screening, confirming the potential good source of antibacterial agents with the highest sensitivity observed. This indicates that this plant extract could be used for the treatment of numerous diseases.
Abstract
Silver conjugated Tetracycline, was created and characterized by ultraviolet visible spectrophotometry (UV-vis), Fourier transform infrared (FT-IR), X-Ray Diffraction Patterns (XRD). Using ...antibacterial assays, the effects of tetracycline alone and drugs-conjugated with silver nanoparticles were tested against Gram-ve
Pseudomonas aeruginosa
isolates by well diffusion assay. The UV-vis spectra of silver-drug Nano conjugates showed a characteristic surface Plasmon resonance band in the range of 400–450 nm. FTIR analysis demonstrated the involvement of Hydroxyl groups in both drugs in the stabilization of silver nanoparticles. (XRD) showed that they cubic structure of silver and, antibacterial assays showed that biosynthesis silver nanoparticle conjugation enhanced antibacterial potential of Tetracycline compared with drug alone.
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