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Electronic packages are employed in diverse industries, including automotive, aerospace, and defense. However, their susceptibility to failure arises from exposure to uncontrolled operating conditions, particularly vibrations.Therefore, an investigation has been conducted to explore the effect of vibration in fatigue life of SAC305 lead free solder material employed in Printed Circuit Board (PCB) assembly with ball grid array (BGA) 144 electronic package. Finite Element Analysis (FEA) of a printed circuit board with BGA 144 electronic package was conducted to find their dynamic characterisics like natural frequencies and their mode shapes. Experiments were conducted to validate the numerically developed model, where first, second and third modes shapes from FEA and experimental results were compared. In addition, random vibration analysis was performed using numerical simulation where individual solder balls were analysed for stress distribution and experimentswere conducted on specially fabricated PCBs using electro dynamic shaker for validation. Analysis shows that the failure was prominent at the solder balls located at the corner of the package. Further, Minor’s rule was used to estimate the fatigue life of the Pb free solder material in BGA 144 package.

Xiaowen Hu,1 Kandasamy Saravanakumar,1 Tieyan Jin,2 Myeong-Hyeon Wang11Department of Medical Biotechnology, College of Biomedical Sciences, Kangwon National University, Chuncheon 200-701, South Korea; 2Department of Food Science and Engineering, College of Agricultural, Yanbian University, Yanji, Jilin, People’s Republic of ChinaBackground: Biogenic silver nanoparticles (AgNPs) have wider range of biomedical applications. The present work synthesized Tp-AgNPs using mycelial extract of endophytic fungus Talaromyces purpureogenus (MEEF), characterized, and analyzed for antibacterial, anti-proliferation and cell wounding healing activities.Methods: The synthesized Tp-AgNPs were characterized by UV-visible spectrophotometer (UV-Vis), field emission transmission electron microscopy (FETEM) with energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), particle size analysis (PSA) and X-ray diffraction (XRD). Further, antibacterial activity was determined by Kirby–Bauer test and anti-proliferation activity was tested in human lung carcinoma A549 by water-soluble tetrazolium and flow cytometer assay. In addition, cell wounding healing activity was determined by scratch assay.Results: UV-Vis results displayed a strong absorption peak from 390 nm to 420 nm, which indicated the successful synthesis of Tp-AgNPs. FETEM-EDS results indicated the round and triangle shaped Tp-AgNPs with the average size of 25 nm in accordance with PSA. FTIR analysis indicated the involvement of various functional molecules from MEEF in the synthesis of Tp-AgNPs. XRD result proved nature of Tp-AgNPs as a high-quality crystal. The Tp-AgNPs significantly inhibited the growth of bacterial pathogens at the minimal inhibitory concentration of 16.12 μg.mL−1, for Gram,+ and 13.98 μg.mL−1, for Gram−, bacteria. Further, Tp-AgNPs (2 μg.mL−1,) showed a strong anti-proliferation effect in A549. Interestingly, Tp-AgNPs was not cytotoxic to normal NIH3T3 cells. In addition, the NPs exhibited a strong cell wounding healing activity.Conclusion: This work biosynthesized AgNPs with strong antibacterial, anticancer and cell wound healing properties using endophytic fungus T. purpureogenus.Keywords: mycosynthesis, silver nanoparticles, Talaromyces purpureogenus, antibacterial, anticancer, cell wound healing

Structural components of composite materials in aerospace industries are assembled using fasteners, installed by performing cutting processes, such as drilling, on the material. In composites, this is considered particularly critical, because delamination due to mechanical stresses and fiber/resin pullout may be facilitated during cutting, so that the structural integrity of composite laminates may be affected. Acoustic emission (AE) technique is employed to monitor the failure modes and damage mechanism of drilled composite materials, while in an attempt to improve the strength of the composites, thermal conditioning has been applied. This paper investigates the residual performance of drilled unidirectional glass fiber reinforced plastic (GFRP) laminates subjected to various thermal conditioning methods. Thermally treated laminates underwent three-point flexural tests under AE monitoring to compare their residual strength with the untreated ones. The results clearly show that the thermal conditioning could be used as an effective method for minimizing delamination in GFRPs.

Internet users have increased everywhere. Searching and retrieving documents is a common thing nowadays. Retrieving related documents from the search engines are difficult task. To retrieve correct documents, knowledge about the search topic is essential. Even though separate search engines are there to retrieve medical documents the users are not familiar with MeSH terms (Medical Subject Heading). So, both the search browser and the MeSH terms have to be integrated to make the search effective and efficient. To implement this integration, SimpleMed and MeSHMed were introduced. The MeSH terms have to be ranked to know how frequently it has been used and to know the importance of the MeSH terms. To rank it a semi – automated tool called MeSHy was developed. The terms were extracted, filtered, ranked and displayed to the user. Classifiers have to be constructed to label the documents as health and non – health. Three strategies were used to classify them. The errors that are commonly done by the users have to be found out. It was calculated based on the queries presented by the user to the search browser.

An arc is used as a heat source in the manufacturing process known as wire arc additive manufacturing (WAAM), which uses layer-by-layer cladding to fuse wire. in the current work, wire arc additive manufacturing (WAAM)-fabricated inconel 625 alloy has been examined. The research was done on the microstructure, mechanical characteristics, and impact of the solidification rate on the characteristics of the manufactured specimens for the inconel 625 alloy. Microstructural analysis has shown that the specimen's layers have varying microstructures. The bottom layer exhibits a blocky or equiaxed microstructure because of the faster solidification rate, while the upper zone generated elongated and discontinuous dendrites because of the slower solidification rate. This difference in the microstructure in the top and bottom zones directly influence the ultimate tensile strength, where the bottom zone has more tensile and yield strength than the top zone. Also, the presence of cracks in the top zone, which is found during the fractography test, also correlated the top zone's ultimate tensile strength. [ABSTRACT FROM AUTHOR]

The aim of this work is to assess the effect of graphene oxide (GO) nanoparticles on performance and emission characteristics of a ceramic coated diesel engine fuelled with ternary blends of pyrolysis oil-methyl ester-diesel. Tyre pyrolysis oil and hemp oil methyl ester (biodiesel) have been produced and PBD20 (10%pyrolysis oil + 10%biodiesel + 80% diesel) blend has been prepared for engine analysis. This work also evaluate the performance and emission characteristics of the engine operated with PBD20 with different dosage of GO in both conventional and partially stabilized zirconia (PSZ) coated engines. Initially, base diesel, 20% blend and 20% blend with different GO dosage level are tested in a standard engine and later, the same fuels are tested in a ceramic coated engine under varying load conditions from 0 to 100%. The performance parameters such as brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), emission parameters such as carbon monoxide (CO), hydrocarbons (HC) and oxides of nitrogen (NOx) are all measured. The results showed that the engine is able to run on blends of tyre pyrolysis oil and hemp oil at different loads, showing similar performance to diesel. From the research, it is noted that PBD20 with 50 ppm GO in a coated engine showed 4.41% higher performance than diesel operated in a standard engine. The BSFC of the engine running on the same blend showed similar trend to diesel. The emission of CO and HC are reduced by 40% and 25.58%, respectively, when the engine operated using PBD20GO50 in coated engine. [ABSTRACT FROM AUTHOR]