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With proper tuning in the phase shift of reconfigurable intelligent surfaces (RISs) or intelligent reflecting surfaces (IRSs), which consist of huge number of passive reflecting elements, are the most promising and transforming technology to reconfigure the wireless propagation ecosystems to improve the “spectral-and energy-efficiency” for the future generation wireless communication system. This article presents a systematic review of RIS/IRS technology and conceptualizes the prospective requirement, operations, and application. Further, we have presented its capability for execution in a forthcoming smart industrial ecosystem to assist the development of Industry 5.0 with a series of emerging applications. Finally, we discuss the potential, open research challenges, and prospects of RIS technology in the emerging intelligent manufacturing industry to encourage future research in this area.

This article presents a comparative analysis of prime and helical interleavers in the OIDMA system. Previous research has explored various interleaver types for OIDMA, including random, tree, prime, and helical interleavers. In this paper, we used a fixed seed length of 7 for the prime interleaver and a fixed helical radius of 100 for the helical interleaver. We estimated the Bit Error Rate (BER) by varying the number of users and thoroughly analyzed the results. The entire OIDMA system was simulated using MATLAB. [ABSTRACT FROM AUTHOR]

Moisture damage resistance assessment in asphalt mixtures traditionally relies on the tensile strength ratio (TSR) method, which may not capture the complex behavior of asphalt under moisture ingress. This study proposes an innovative multifaceted approach for assessing moisture susceptibility, challenging the overreliance on TSR, and integrating multiple intricate aspects of asphalt behavior. Employing two dense-graded and one gap-graded polymer-modified binder mixtures with nominal maximum aggregate size (NMAS) of 13 and 19 mm, the study defines threshold values for total air voids, effective air voids, indirect tensile strength, and percentage density change. Evaluations were conducted using a device selected for its dynamic capabilities in inducing stresses and creating pore pressure under elevated temperatures. This research proposes a new zone-based approach to classify mixtures as moisture-resistant, partially moisture-resistant, or moisture-susceptible. This innovative method, grounded on maximum effective air voids and percentage density change, offers nuanced insights for more accurate moisture resistance assessments. Furthermore, the study explores the effect of effective air void size on moisture damage resistance by image processing for dense and gap-graded gradation of 13.2 NMAS, unveiling clogging behavior especially in dense-graded mixture due to smallest pore size. In conclusion, the study provides an in-depth understanding of asphalt mixture behavior under moisture ingress. By offering a novel approach that integrates multiple parameters and extends beyond the conventional TSR approach, it contributes a practical solution for mitigating moisture damage in asphalt mixtures. This research sets the stage for a potential paradigm shift in the approach to moisture susceptibility assessment, enriching the asphalt field with critical insights. [ABSTRACT FROM AUTHOR]

The direct drive Permanent Magnet Linear Generator (PMLG)-based Ocean Wave Energy Converters (OWECs) produce variable A.C. voltage. In this article, the variable A.C. voltage is converted into a variable D.C. voltage by a standard rectifier. After that, a buck–boost inverter is used to produce constant amplitude A.C. voltage at the load end. The buck–boost inverter, implemented here, operates in three modes: buck, boost, and buck–boost. Furthermore, a switching algorithm is developed to generate reference A.C. voltage. Systematic design of power converter, small-signal analysis, and PWM control strategy are discussed. The simulation results and results from a laboratory prototype are presented to support the theoretical concepts. [ABSTRACT FROM AUTHOR]

Background: Sub-arachnoid block is most commonly used technique in regional anaesthesia to conduct lower limb surgeries [1]. Wide variety of adjuvants have been used intrathecally to prolong post-operative analgesia. The aim of this study is to evaluate and compare the intra-operative block characteristics and duration of postoperative analgesia by using intrathecal dexmedetomidine (5μg) or nalbuphine(1mg) as an adjuvant to hyperbaric bupivacaine (12.5mg) in lower limb orthopedic surgeries. Aims and objectives: This study is used to compare the effects of dexmedetomedine and nalbuphine when given as an adjuvant to hyperbaric bupivacaine in sub-arachnoid block. Material and methods: This study was prospective, randomized, double-blind study. After obtaining ethical committees' clearance and informed consent, sixty patients of either sex, and ASA physical status I and II scheduled for sub-arachnoid block were included and categorized into two groups(n=30). Result: Addition of dexmedetomedine with hyperbaric bupivacaine intrathecally when compared with nalbuphine result in faster onset of both motor and sensory blockade, with statistically significant longer duration of post-operative analgesia. Conclusion: Both dexmedetomidine and nalbuphine can be used as adjuvant to hyperbaric bupivacaine in spinal anaesthesia but dexmedetomidine along with bupivacaine provide better quality of anaesthesia, and excellent post-operative analgesia when compared with nalbuphine. [ABSTRACT FROM AUTHOR]

BACKGROUND AND AIMS: Endotracheal intubation is the first step to maintain the patency of airway during general anaesthesia. Problem with the airway management constitutes 17% of anaesthesia closed claim, most common being difficult intubation which is almost 5%. The aim of this study is to compare the time, ease, numbers of attempts taken, switching between the laryngoscopes if facing any difficulty during endotracheal intubation while using Macintosh laryngoscope, KingVision laryngoscope, Anaesthetics video laryngoscope. MATERIAL AND METHODS: In this Prospective observational study Ninety patients, scheduled for elective surgery after getting approval from ethical committee and informed written consent from all patients, the prospective observational study was conducted on adult patients of either sex satisfying inclusion criteria. In our study patients were randomized into 3 groups (30 patients in each group), patient who got intubated with Macintosh laryngoscope (Group M), patient who got intubated with KingVision video laryngoscope (Group K), patient who got intubated with Anaesthetics video laryngoscope (Group A). All the three groups were compared for time, ease and attempts to successful endotracheal intubation while using Macintosh laryngoscope, KingVision laryngoscope, Anaesthetics video laryngoscope. RESULTS: The mean time taken has been found to be significantly lesser in Group A as compared to Group M and Group K. The intubation difficulty score was found statistical insignificant in all the three groups (p value: 0.956). The comparison between Mallampati score and Cormack-Lehane grading was significant in Group A (p value <0.001) and Group K (p value< 0.033). CONCLUSION: It can be concluded that Anaesthetic video laryngoscope is better when considering the intubation time (takes lesser time for intubation), number of attempts (takes lesser number of attempts for intubation) and stylet used (less stylet used in case of Anaesthetic video Laryngoscope). [ABSTRACT FROM AUTHOR]

BACKGROUND AND AIMS: Laparoscopic surgeries, despite being minimally invasive, is not popular as a day care surgery because of the post operative pain and requirement of intravenous analgesic drugs. The aim of this study is to compare the efficacy of intraperitoneal instillation of levobupivacaine alone versus levobupivacaine with different doses of dexmedetomidine for post operative analgesia in patients undergoing laparoscopic cholecystectomy. Materials and Methods: Prospective observational study. In the study, 100 patients, scheduled for elective laparoscopic cholecystectomy after getting informed and written consent were taken up and were randomised into 4 groups to receive either 50 ml of 0.25% levobupivacaine + 5ml normal saline [GROUP A], 50ml of 0.25% levobupivacaine + dexmedetomidine 0.5mcg/kg diluted in 5ml normal saline [GROUP B], 50ml of 0.25% levobupivacaine + dexmedetomidine 1mcg/kg diluted in 5ml normal saline [GROUP C], 50ml of 0.25% levobupivacaine + dexmedetomidine 1.5mcg/kg diluted in 5ml normal saline [GROUP D]. Study drug was instilled before the removal of the trocar at the end of the surgery. All the patients also received infiltration of 0.25% bupivacaine at the port sites. Post operative pain using NRS, time to first rescue analgesia and total analgesic requirement of the patients amongst all the four groups was observed and compared. RESULTS: The mean NRS was found to be significantly lesser in Groups C & D as compared to Groups A & B. Inj. Fentanyl [1-2mcg/kg] was used as rescue analgesia for patients with NRS>4. Patients belonging to Group A received rescue analgesia earlier and higher as compared with Group B. Patients belonging to Group C & D did not require any rescue analgesia. CONCLUSION: The addition of dexmedetomidine to levobupivacaine for intraperitoneal instillation was found to be more efficacious for post operative analgesia and 1mcg/kg of dexmedetomidine can be used as optimal adjuvant dose with levobupivacaine in patients undergoing laparoscopic cholecystectomy. [ABSTRACT FROM AUTHOR]

The additive manufacturing method based on powder feed type laser Directed Energy Deposition (DED) is projected to be able to create objects with intricate structures. The intricate thermal history that occurs during DED causes variations in the top surface roughness, which is an important quality index for DED and has a significant impact on the lifespan of the samples. Surface quality is always desirable, mostly in the case of dynamic loading applications. This article presents a methodical investigation into the top surface roughness of the Inconel 718 alloy during various scanning strategies in the DED. This alloy is utilized extensively in the aerospace, automotive, and military industries. Multilayer cuboid samples are fabricated using four scanning strategies. Using different scan strategy, no significant changes in pore size and amount of porosity was observed, but significant changes were observed for the surface quality of printed Inconel alloy. [ABSTRACT FROM AUTHOR]

DMLS fabricated IN718 alloy samples with various build orientations are analysed with heat-treatment dependent mechanical and microstructural properties. The multiple heating and cooling cycles formed a complex micro-heterogeneous microstructure composed of columnar and equiaxed subgrains in the alloy. Solution treatment resulted in a partially dissolved δ phase, and the metastable γ" phase while ageing treatment eliminated the dendritic substructure. In contrast, δ-phases precipitated mainly in the interdendritic regions, and significantly eliminated the micro-segregation and Laves phases in the γ matrix after homogenised (HSA).. The tensile test showed that tensile strength decreased with increasing building orientation but ductility increased. Heat-treatment significantly improved the microhardness, ultimate tensile strength, and yield strength compared to the as-fabricated samples, but their ductility decreased. The tensile properties recorded an improvement of nearly 31.32% as compared to 0° as-built and 0° heat-treated direct aged samples. The higher microhardness (507.25 HV) was observed for the direct aged 0° build samples. The microhardness values were increased by nearly 45% after heat-treatment comparing to as-build 0° and 0° DA treated samples. The density was observed to be about 99.52% of the as-built samples, but performing the heat-treatment, no significant improvement in the density was observed and it was found similar to the as-fabricated sample. [ABSTRACT FROM AUTHOR]