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This paper presents an automated or intermittent wire feeding method in tungsten inert gas (TIG) welding. The preliminary investigation shows the macrostructure, microstructure, and mechanical property effects on various welding parameters using one combination proportion of filler metal with various welding parameters. The result of microstructure has shown that the localized segregation occurred at the center area weld metal with high-density eutectic phase and energy dispersive X-ray spectroscopy (EDS) study has found that Mg content was higher compared to the outside region. Other sample microstructure shows columnar structure was formed in dilution boundaries, and it reveals that fast cooling rates happened when the filler wire was inserted. Also, microstructure on weld traverse section shows that the wavy-like structure depended on the heat input. The fracture mode shows that lack of heat input is susceptible to oxidation; therefore, the fracture tends to occur at weld metal in the brittle manner with reduced strength of more than 40%. Also this article presented the method to calculate length ratio (RL) and the volume ratio (RV) to estimate the minimum value of ratio under the condition of a good welded surface profile. [ABSTRACT FROM AUTHOR]

A new configuration of permanent magnet as a source of external magnetic field has been established to an autogenous tungsten inert gas (TIG) welding. The external magnetic field is generated by rectangle shape NdFeB permanent magnets of 260 mT and arranged in cups-type magnetic field (CMF). A charge-coupled device (CCD) is applied to monitor the phenomenon of the arc shape. The material used in this experiment is SS304 with a thickness of 2 mm. This study aims at investigating the effect of external magnetic field towards the arc shape and finding the configuration, which can reduce the power consumption and improve penetration. A significant effect on the improvement of welding efficiency can be achieved by using PR-NNSS-SD (50 or 70 mm), PP-NNSS-SD (70 or 90 mm), or PP-NSNS-Pull (50 mm). These configurations can reduce the power consumption up to 11%. [ABSTRACT FROM AUTHOR]

Data of Staphylococcus aureus carriage in Indonesian hospitals are scarce. Therefore, the epidemiology of S. aureus among surgery patients in three academic hospitals in Indonesia was studied. In total, 366 of 1,502 (24.4%) patients carried S. aureus. The methicillin-resistant S. aureus (MRSA) carriage rate was 4.3%, whereas 1.5% of the patients carried Panton-Valentine leukocidin (PVL)-positive methicillin-sensitive S. aureus (MSSA). Semarang and Malang city (odds ratio [OR] 9.4 and OR 9.0), being male (OR 2.4), hospitalization for more than 5 days (OR 11.708), and antibiotic therapy during hospitalization (OR 2.6) were independent determinants for MRSA carriage, whereas prior hospitalization (OR 2.5) was the only one risk factor for PVL-positive MSSA carriage. Typing of MRSA strains by Raman spectroscopy showed three large clusters assigned type 21, 24, and 38, all corresponding to ST239-MRSA-SCCmec type III. In conclusion, MRSA and PVL-positive MSSA are present among patients in surgical wards in Indonesian academic hospitals.