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In this study, temperatures of samples welded by 3 different welding sorting has been measured and displacements occurring on the part after wielding have been determined and an experimental comparison has been made in this regard. The welded part belongs to the front loader used in tractors. Material of the model is S355j2+N. In the experimental study, 3 samples have been welded for each process. In Process 1, welding lines have been observed outside to inside, in Process 2 inside to outside, and in Process 3 from right to left. For all parts, welding parameters and welding speed have been fixed. Welding manufacture and cooling processes have lasted 3000 seconds in total. 4 points have been determined in order to measure the temperature of the part during the experiment. For determination of displacement amount, sample parts have been measured by means of 3-dimensional laser measuring device before and after welding. When results of experiment are examined, it has been observed that temperatures curves are similar in processes no. 1 and 3; and the process has been completed by lower temperature in process no. 2. The highest temperatures measured in processes 1, 2 and 3 are respectively as 380°C, 272°C ve 310°C. Displacements of circular and cylindric points are respectively as 2.17 mm, 1.22 mm, 2.12mm. Maximum displacements of the surfaces are as 0.40 mm, 0.41 mm, 0.80 mm for process 1; as 0.10 mm, 0.28 mm, 0.83 mm for process 2; and as 0.71 mm 0.77 mm 1.39 mm for process 2. It has been concluded that process no. 2 has lower temperatures and less displacements. Less amount of displacement or distortion provides use of parts without applying correction afterwards, and eliminates surplus workmanship and time loss. [ABSTRACT FROM AUTHOR]

Hardware impairments in general and amplifier nonlinearity in particular severely limit the performance of communication links. This paper analytically provides statistical results on how a nonlinear amplifier affects the quality of signals in communication systems. In particular, we propose a statistical model that describes the nonlinear distortion as a function of the input signal’s average and instantaneous power and captures the pulse-shaping and matched filters’ effects. We show through simulations and complementary measurements that the proposed model can provide an authentic connection between the communication system parameters, power amplifier nonlinearity characteristics, and the communication system performance. It serves not only as a reliable model for nonlinear distortion analysis but also as a design tool that allows optimization of signal and filter characteristics with respect to nonlinear distortion. [ABSTRACT FROM AUTHOR]