%0 Journal Article %T Transformation of User Interface to Activity Models and Assessing Performance of WA/WS %A Ch. Ram Mohan Reddy %A D. Evangelin Geetha %A R. V. Raghvendra Rao %A T. V. Suresh Kumar %J Journal of Software Engineering and Applications %P 101-126 %@ 1945-3124 %D 2019 %I Scientific Research Publishing %R 10.4236/jsea.2019.125008 %X Quality of Service is an important attribute of a software system. In retrospect, performance assessment based on user interaction with the system has given a better understanding of underlying disciplines of the product. In this paper, we capture user interaction with the prototype/User Interface (UI). An approach for developing activity model from the user interface model is presented using workflows and functional elements. A methodology is proposed to transform UI into activity diagram. The approach is validated by an experimental setup using Amazon service. The performance of Amazon service is assessed using activity based performance prediction methodology, and the simulation results are obtained using SMTQA. %K Web Services %K Software Performance Engineering %K Web Applications %K Software Size Estimation %K Activity Based Performance Prediction %K Unified Modeling Language %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=92562