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This work optimizes the current (I), voltage (V), flow rate (F), and arc gap (G) of the gas tungsten arc welding (GTAW) of the Ti40A titanium alloy to decrease the heat input (HI) and improve the ultimate tensile strength (TS) and micro-hardness (MH). The radial basis function network (RBFN) was utilized to present performance measures, while weighted principal component analysis (WPCA) and an adaptive nondominated sorting genetic algorithm II (ANSGA-II) were applied to estimate the weights and generate optimal points. The evaluation via an area-based method of ranking (EAMR) was employed to determine the best solution. The results indicated that the optimal I, V, F, and G are 89 A, 23 V, 20 L/min, and 1.5 mm, respectively. The improvements in the TS and MH were 1.2 % and 19.8 %, respectively, while the HI was saved by 18.4 %. The RBFN models provided acceptable accuracy for prediction purposes. The ANSGA-II provides better optimality than the conventional NSGA-II. The HI, TS, and MH of the practical GTAW Ti40A could be enhanced using optimality. The optimization method could be utilized to deal with optimization problems for not only other GTAW operations but also other machining processes. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of foreign direct investment (FDI) flows on trade-based money laundering (TBML). Trade misinvoicing, including export under-invoicing and import over-invoicing, is a proxy of TBML. Using an extended gravity model in trade with data from Vietnam from 2000 to 2019, our empirical results show that FDI flows are positively associated with TBML, which supports the FDI-fueled capital flight hypothesis. Departing from the current literature, we show that this effect becomes pronounced for export under-invoicing when Vietnam trades with low-income and lower-middle-income countries. Moreover, this effect is negatively moderated by government effectiveness and economic freedom. Our findings are appealing because Vietnam is an export-oriented, FDI-dependent economy; however, trade misinvoicing may offset the contribution of FDI to Vietnam's economic development. Hence, our findings suggest a number of policy implications for policymakers in attracting FDI. [ABSTRACT FROM AUTHOR]