Dissimilar Joining of Metals by Powder Metallurgy Route

Dissimilar metal joints have a wide range of applications in electronic connectors, due to its physical and mechanical properties. In the present work powder brazing is chosen as a tool for joining of Cu-SS, Cu-Fe, and Cu-Ni. Powder brazing of dissimilar metals has advantages over conventional joining techniques which does not involve melting of the base metal and thus avoids the problems associated with, variation in thermo-physical properties and leads to formation of high amount of undesirable compounds (high intermetallic layer at the joint interface) as a result high joint strength cannot be achieved, an able solutions to produce this type of joints has been developed. In the present work three different types of powder are chosen for brazing, Copper (Cu)-Stainless Steel (SS), Copper-Iron (Fe), Copper-Nickel (Ni) powders. Cu weight (2 gram), stainless steel powder (2 gram), iron powder (2 gram), and Nickel powder (2 gram), then the specimen were compacted with varying loads (4, 5, and 6 tonne), the compacts were in the shape of cylinders. The compacts were sintered at 900 °c in argon atmosphere with a heating rate of (10 k/min), the specimens were cross sectioned using abrasive cutting machine, mounted and polished for macroscopic and microscopic observation. The mounted specimens were polished with emery paper of 1/0, 2/0, 3/0, and 4/0 and were subjected to chemical etching using nital solution. To study macro and microstructures of the specimen optical and scanning electron microscope was used. Form the macrostructures it was observed that there is no presence of cracks in all the joints. It was observed that with the increases in compaction load there is a better bonding between the joints. Microstructures did not show any presence of Intermetallics. Form the hardness data it was confirmed that there is a presence of Intermetallics due to marginal variation in the hardness at the interface in all the cases. From the compression test it was observed that with the Cu-Ni has shown improved strength compared to Cu-SS and Cu-Fe. At higher compaction loads the specimens has shown higher strength in the all the cases (Cu-SS Cu-Fe, Cu-Ni) may be due to better bonding

Global Economic Crisis: Impact and Restructuring of the Services Sector in India

The Indian economy has shown considerable resilience to the global economic crisis by maintaining one of the highest growth rates in the world. The services sector accounted for around 88% of the growth rate in real gross domestic product in 2008–09. To demystify the relatively resilient growth of the services sector in India, this study examines both the demand-side and the supply-side factors that have contributed to its growth. To assess the role of external demand, income elasticity of export demand for the aggregated services and some of the disaggregated services of India were estimated.indian services sector; indian economy; global economic crisis

Comparison of Multi-Criteria Decision Making Methods for Multi Optimization of GTAC Process Parameters

A great deal of investigation on gas tungsten arc cladding (GTAC) is focused on the study of enhancements in the microstructure, mechanical and tribological features of the cladding. The selection of right process parameters is a critical issue for the researchers. Decision makers in the industries must analyze a wide variety of parameters based on a set of contradictory criteria. Several multi-criteria decision-making (MCDM) techniques are now available to add values in selection of these parameters. The application of the TOPSIS and MOORA techniques to identify the best configuration of processing parameters in the gas tungsten arc cladding (GTAC) process is investigated in this work. The best processing parameters set for the multiple performance attributes should be welding current: 70 amp, speed: 240, argon flow: 13 and standoff distance 3.5 (TOPSIS-PCA) and welding current: 50, speed: 300, argon flow: 13 and standoff distance 3.5 (MOORA-PCA).A comparison of MOORA-PCA and TOPSIS-PCA demonstrates the superiority of TOPSIS over MOORA technique. The prediction accuracy of the TOPSIS-PCA hybrid approach model is found better than MOORA-PCA technique

Prediction of the aerodynamic behavior of a rounded corner square cylinder at zero incidence using ANN

AbstractThe aerodynamic behavior of a square cylinder with rounded corner edges in steady flow regime in the range of Reynolds number (Re) 5–45; is predicted by Artificial Neural Network (ANN) using MATLAB. The ANN has trained by back propagation algorithm. The ANN requires input and output data to train the network, which is obtained from the commercial Computational Fluid Dynamics (CFD) software FLUENT in the present study. In FLUENT, all the governing equations are discretized by the finite volume method. Results from numerical simulation and back propagation based ANN have been compared. It has been discovered that the ANN predicts the aerodynamic behavior correctly within the given range of the training data. It is additionally observed that back propagation based ANN is an effective tool to forecast the aerodynamic behavior than simulation, that has very much longer computational time

Expression of Dkk 1 in Endometrial Endometrioid Carcinoma & Its Correlation with Wnt / β-catenin Signaling Pathway

Objective: Endometrial cancer is the most common form of cancer affecting female reproductive organs. Most common histologic type endometrioid carcinoma constitutes 75 to 80% of all cases. Studies on Dkk1 expression profiles and its inhibitory role in Wnt signaling pathway in genesis and development of endometrial carcinoma are very few. This study aims to investigate Dkk1 expression in endometrial carcinoma and its correlation with Wnt/β-catenin pathway. Methods: A total of 160 formalin fixed paraffin embedded samples including 50 cases each of endometrial atypical hyperplasia and endometrioid endometrial carcinoma along with 30 cases each of proliferative and secretory endometrium were included in this study. We investigated expression pattern of Dkk1, E-cadherin, β-catenin and c-myc in endometrial atypical hyperplasia and carcinoma as well as compared with that of proliferative and secretory endometrium. Immunohistochemistry and analysis were performed from July, 2018 to June, 2020. Results: We showed decreasing pattern of immunopositivity for Dkk1, E-cadherin and β-catenin from proliferative/secretory endometrium to endometrial atypical hyperplasia and endometrioid carcinoma. Increasing c-myc immunopositivity was noted from proliferative/secretory endometrium to endometrial atypical hyperplasia and endometrioid carcinoma. Moreover, decreasing Dkk1 immunopositivity was well correlated with both E-cadherin, β-catenin and c-myc immunopositivity. Conclusion: Decreasing Dkk1 positivity from benign endometrium to endometrioid carcinoma suggests a negative regulatory function of Dkk1 in endometrioid carcinoma. Dkk1 is downregulated in Wnt signaling pathway in endometrioid endometrial carcinoma. Thus, Dkk1 can show promise as a biomarker for screening endometrioid carcinoma. Future researches can study the reactivation of the Dkk1 gene that could be a valuable strategy for antagonizing Wnt signaling pathway. Keywords: Endometrioid carcinoma, Dkk1, Wnt/β-catenin pathway, β-catenin, E-cadheri

Grape extract protect against ionizing radiation-induced DNA damage

Grape extracts of different cultivars (Flame seedless, Kishmish chorni, Red globe and Thompson seedless) were investigated for in vitro antioxidant activity by ABTS assay, and compared protective efficacy against radiation-induced DNA damage. Seed extract showed the highest scavenging activity, followed by skin extract. Among different cultivars, ‘flame seedless’ skin extract showed higher scavenging activity followed by ‘Kishmish chorni’ skin extract. Grape extracts significantly prevented radiation-induced plasmid DNA damage. Super-coiled pBR 322 plasmid DNA (~93%) is completely converted to open circular (~97%) and linear (~2%) form at a dose of 150 Gy γ-radiation. Pretreatment with different grape extracts showed various degree of protection against radiation-induced DNA damage. Pretreatment with 1.6 µg grape skin extract of ‘Thompson seedless’ cultivar or grape flesh extract of any tested cultivar diminished the DNA strand breaks, and there was an increase in the super coiled form of DNA against 150 Gy of γ-radiation. However, pretreated pBR 322 DNA with the skin of ‘Kishmish chorni’ cultivars or seed of ‘red globe’ grape cultivars remained static during electrophoresis and confined in the groove on exposure to 150 Gy γ-radiation treatment. Co-treatment with the skin of red globe cultivar also partially confined plasmid DNA in the groove. The same trend was observed when plasmid DNA was exposed to 1.2 kGy γ-radiation. Our investigation revealed that anthocyanin present in grape skin was probably involved in radio protective activities through the formation of co-pigmentation with DNA

Design of RTU & SCADA

Abstract:This work aims at designing a system with which the various parameters viz. Frequency(Hz), Bus-bar Current(kA),Bus-bar Voltage(kV), Reactive Power(MVAR),ActivePower(MW) and equipments like Isolator ,Relay ,Circuit Breaker of Sub-Station orGenerating Station can be monitored and controlled from a remote location . To achieve the desired output Remote Terminal Unit(RTU) will be placed in the Sub-Station or Generation Station which will acquire the various data and these data will be transmitted to the SCADA(Supervisory Control and Data Acquisition) station of RLDC (Regional Load Despatch Centre) . In this work, Arduino integrated with Step Down Voltage Transformer , ACS712 Hall Effect Current Sensor and SPDT Relay is configured as RTU and a PC loaded with a GUI is configured as SCADA(Supervisory Control and Data Acquisition).Keywords: RTU,SCADA,Arduino,PC,GUI,ACS712 Hall Effect Current Sensor, RLDC.(Article history: Received 29 April 2016 and accepted 30 December 2016