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Abstract. Few aspects of shunting effect have been studied so far. Shunting effect in resistance spot welding (RSW) occurs when the electrical current passes through the previous spot welds. Value of this current depends mostly on distance, number, and size of previous spot welds. This will cause some dimensional and metallurgical changes in welding nugget as well as heat affected zone (HAZ). In this study, shunting effect of RSW is considered by finite element method (FEM) and the results are compared to experiments performed on aluminum alloy 2219. Weld spacing together with welding current and time are considered to discover the effect of shunting current in the final quality of nugget. A three factor experiment design has been performed to find the significance of factors and interactive effects, as well as finite element model verification. Electrothermal and mechanical interactions are considered in the FEM. Experimental and numerical solutions have yielded similar results in terms of welding nugget properties. Asymmetry in electrical potential, temperature, stress distribution and geometry of shunted nugget is predicted and verified directly or indirectly. Intense effect of shunting current on nugget height, asymmetric growth of heat affected zone (HAZ) toward previous welding nugget, as well as concentration of alloying elements along grain boundaries are also discovered. Kim et al. [17]). Although most of these studies have included thermal, electrical and mechanical aspects of the RSW process, the asymmetry of shunting configuration due to existence of shunting (previous) nugget prohibits the use of 1D or 2D axisymmetric models.In this paper, shunting effect in RSW is investigated using FEM and the results are compared with experiments on AA2219. The influence of welding distance, current and time are investigated to consider shunting effect in final quality of the nugget. Experiments are designed inside the weldability range, while the results are compared to results of FEM after verification. have included thermal, electrical and mechanical aspects shunting configuration due to existence of shunting (prev 2D axisymmetric models. MethodsIn this paper, shunting effect in RSW is investigated using with experiments on AA2219. The influence of welding d investigated to consider shunting effect in final quality of inside the weldability range, while the results are compar

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The indices of housing serve as an important tool in planning for housing, in that they allow the parameters affecting housing to be recognised and any planning process to be facilitated. The purpose of the study is to investigate and to evaluate the housing situation in cities of Isfahan province. The study is applied and descriptive-analytic in terms of method. Thirty-nine indices were collected in the housing sector. Then the rate of prosperity and ranking of the cities were evaluated by TOPSIS method. Prosperity is defined here as an important index of housing that reflects the welfare of residents. The cities were then categorised into six levels of prosperity: Very important, Important, Partially important, Moderate, Poor and Very poor. The results from the study indicate an imbalance in the studied indices between the cities, and a clear disparity between the levels of prosperity in the cities, and the only city in the very prosperous group is Isfahan, with a rate of 0.813.