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In high-speed microelectronic communication, efficient and reliable radome-enclosed antenna performance is highly desired, which depends on consistent dielectric, mechanical properties, and low moisture absorption. The purpose of this study is to investigate the dielectric properties of fiber-polymer matrix composite (PMC) radome over wideband frequency and the impact of environmental aging on its performance. The dielectric constant (εr) of the SF/E0.8 (80% fiber loading) composite radome material decreased to 4% from its original value (3.93), and dielectric loss (δ) was reduced by 11% from 0.035 (2-18 GHz), while SEM morphology indicated fair interface bonding. Employing the Hallberg and Peck model, equivalent aging time (5-25 years), upon accelerated environmental aging, εr was increased up to 3.69%, δ to 9.68%, and the moisture uptake in the SF/E0.8 composite was increased from 1.13% to 1.67%, while tensile strength was retained up to 90.62% of its original value (147.83 MPa), compression strength up to 93.56% of its original value (388.54 MPa), flexural strength up to 85.44% of its original value (286.77 MPa), and interlaminar shear strength up to 77.66% of its original value (22.03 MPa), respectively. SF/E0.8 radome-enclosed antenna gain was decreased to 1%, and the voltage standing wave ratio (VSWR) was increased to 1.04% from their original values. This gradual and small deviation of SF/Ex composite properties and radome electrical performance over the extended aging time is referred to as reliable and effective for radome applications. [ABSTRACT FROM AUTHOR]

Vinyl ester/flax (VE/flax) bio-composites were made after incorporating hybrid concentrations (0, 3, and 6% by weight (wt)) of halloysite nanotubes (HNT), magnesium hydroxide (MHO) and chitosan infused ammonium polyphosphate (CAP) particles. The purpose of incorporation of these particles was to improve the fire-retardant (FR) properties of the VE/flax composite; however, its effect on mechanical properties was also evaluated. To reduce the number of experiments (from 27 to 9), Taguchi design of experiment was employed during composite fabrication phase. Initially, the burning time and burning rate of all the composites were calculated using a horizontal burning test while tensile properties were determined using a tensile test. To predict an optimum composition, a signal to noise (S/N) ratio analysis of the burning time and tensile strength was conducted as "larger is better" criteria. The combination of 6% MGO and 3% CAP was predicted to be an optimum hybrid filler for enhanced fire retardancy, while VE/flax composite with no filler proved to have the highest tensile strength. HNT was found to be the least effective filler for both tensile and fire-retardant properties. The predicted composition was then fabricated and validated through experimental characterizations. The fire-retardant properties of the optimized composite were additionally assessed using a limiting oxygen index (LOI) test and thermal stability was evaluated using a thermogravimetric analysis (TGA). The burning time of the optimized composite was found to be delayed by 46.5% of that of VE/flax composite, while its thermal degradation was 11.23% lower than VE/flax composite. [ABSTRACT FROM AUTHOR]

The current work was undertaken with the research aim of experimental examination of tool wear, surface roughness and burr formation during the micro-milling of Inconel 718 using different coated tools. Inconel 718 is one of the most widely used materials for purpose-oriented utilization owing to its preferred mechanical and physical properties, including high strength and corrosion resistance. On the opposite end, the machining of Inconel 718 poses certain machinability challenges, which significantly elevates tool wear and subsequently surface roughness. Cutting speed, feed rate and depth of cut were selected as variable machining inputs. With reference to tool wear, all input variables were found to be significant, with tool coating having the highest contribution ratio of 36.19%. In case of surface roughness, cutting speed and tool coating were identified as effective input parameters with contribution ratios of 51.24% and 34.27%, respectively. Similarly, depth of cut proved to be an influential factor for burr height formation (in both up-milling and down-milling), whereas feed rate had the highest contribution ratios for burr width formation during up-milling and down-milling, i.e., 39.28% and 36.26%, respectively. Consequently, contour plots for output responses were drawn between significant parameters to analyze machinability. One of the vital research outcomes was the identification of a tool coating parameter that is significant for all four analyzed aspects of burr formation. In addition, regression equations were formulated for machining responses. The best- and worst-case scenarios for individual input parameters, as identified from main effects plots, were validated during confirmatory experimentation. Moreover, effects of input variables on output response were characterized using close-up imagery, and dominant wear mechanisms were also identified. The utility of the research is underlined by the optimization of the sustainability and productivity of the manufacturing process. [ABSTRACT FROM AUTHOR]

Titanium grade 9 (Ti-3Al-2.5V) stands out as a preferred material in various industrial applications because of its suitable properties. Its applications span diverse sectors, including precision manufacturing, where it is utilized to produce honeycomb structures for advanced aeronautics, as well as for certain biomedical components. In parallel, micro-milling has gained widespread utilization across medical, aerospace, and electronic industries due to the increasing demand for miniature products in these domains. This current research study aims to explore the impact of various micro-milling process parameters—specifically, feed rate, cutting speed, and depth of cut—on the surface quality, burr formation, and tool flank wear of titanium grade 9. Research findings reveal that the feed rate plays a major role in influencing surface roughness (contribution ratio (CR): 62.96%) and burr formation (CR: 55.20%). Similarly, cutting speed and depth of cut significantly affect surface roughness, contributing 20.32% and 9.27%, respectively, but are insignificant factors for burr width. Tool flank wear is primarily influenced by cutting speed (CR: 54.02%), with feed rate contributing 33.18%. Additionally, the feed rate and cutting speed are significant factors in determining the length of the burr, with contribution ratios of 77.70% and 7.77%, respectively. Confirmatory tests conducted at optimum parameters selected from the main effects plot validated the experimental results. [ABSTRACT FROM AUTHOR]

Economy and productivity are the two most important elements of modern manufacturing systems. Economy is associated with energy-efficient operations, which results in an overall high input-to-output ratio, while productivity is related to quality and quantity. This specific work presents experimental investigations of the use of cooling conditions (dry, MQL and wet) as input variables alongside other input parameters, including depth of cut, feed and cutting speed. This research aimed to investigate the variation in output responses including tool wear, specific cutting energy, and surface roughness while machining Inconel 718, a nickel-based super alloy. For experimentation, three levels of depth of cut, feed, and cutting speed were chosen. The Taguchi method was used for the experimental design. The contribution ratio of each input parameter was ascertained through analysis of variance (ANOVA). Use of coolant showed a positive effect on process parameters, particularly MQL. By adapting the optimum machining conditions, specific cutting energy was improved by 27%, whereas surface roughness and tool wear were improved by 15% and 30%, respectively. [ABSTRACT FROM AUTHOR]

Symmetry is a key part of the study of basic forces and particles, as well as the creation of mathematical models that help scientists in various scientific disciplines understand complex events. Scientists can figure out what a system is made of and how it works by looking at its symmetry. They can then use this information to make predictions and create new materials and technologies. Humanity has conquered many once-fatal diseases due to medical research and technological advancements. Although this progress is encouraging, there are still a great many areas that require continual human efforts. An effort is made in this article to choose the best treatment strategy to completely manage the pandemic of COVID-19 under conjunctive complex fuzzy knowledge. In this paper, the concept of conjunctive complex fuzzy relations is presented and numerous set theoretical aspects of this phenomenon are established. The investigation of this ideology is further expanded to describe different sorts of essential structural conjunctive complex fuzzy relations. Matrix and graphical representations of the formation of these newly specified relations are also provided. Moreover, this concept has been successfully employed to provide a therapy strategy for a rapid recovery from COVID-19. Furthermore, a comparative analysis is conducted to demonstrate the validity and applicability of the suggested approaches compared to existing methods. [ABSTRACT FROM AUTHOR]

In this paper, the concept of Neutrosophic LA-rings is introduced. Furthermore, we investigate their algebraic structures. We discuss various types of ideals and establish a number of results to better understand the characteristic behavior of Neutrosophic LA-rings. In addition, we investigate the properties of the Neutrosophic M-system, Neutrosophic P-system, and Neutrosophic I-system in order to characterize the Neutrosophic LA-ring. [ABSTRACT FROM AUTHOR]