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% Define block styles
\tikzstyle{decision} = [diamond, draw, fill=green!20,
text height=2em, text badly centered, node distance=4cm, inner sep=0pt]
\tikzstyle{block} = [rectangle, draw, fill=blue!20,
text centered, rounded corners, minimum height=4em]
\tikzstyle{line} = [draw, very thick, color=black!50, -latex']
\tikzstyle{cloud} = [draw, ellipse,fill=red!20, node distance=3cm,
minimum height=2em]
\begin{figure}[H]
\begin{tikzpicture}[scale=2, node distance = 2cm, auto]
% Place nodes
\node [block] (Solve) {Find solution of Transfer Function (TF)};
\node [cloud, left of=Solve, node distance=6cm] (start) {START};
\node [block, below of=Solve] (identify) {Identify climatic conditions};
\node [block, below of=identify] (SolveT) {Iterate TF in MATLAB};
\node [block, right of=SolveT, node distance=5cm] (Experiment) {Run Experiment};
\node [block, below of=SolveT, node distance=2cm] (Compare) {Compare predicted vs experimental};
\node [block, below of=Compare] (Calibrate) {Calibrate by MATLAB regression leaner};
\node [block, below of=Test] (Test) {Test with $T_{exp}$};
\node [decision, below of=Calibrate, node distance=3cm] (Decide) {Correlated?};
\node [block, below of=Decide] (Validate) {Validate model};
\node [cloud, below of=Decide, node distance=3cm] (stop) {STOP};
% Draw edges
\path [line,dashed] (start) -- (Solve);
\path [line] (Solve) -- (identify);
\path [line] (identify) -- (SolveT);
\path [line] (identify) -| (Experiment);
\path [line] (SolveT) -- (Compare);
\path [line] (Experiment) |- (Compare);
\path [line] (Compare) -- (Calibrate);
\path [line] (Calibrate) -- (Test);
\path [line] (Update) -- (Calibrate);
\path [line] (Test) -- (Decide);
\path [line] (Decide) -| node {No}(Update);
\path [line] (Decide) -- (Validate)
\path [line,dashed] (Validate) -- node {Yes}(stop);
\end{tikzpicture}
\caption{The research design's process conceptual diagram}
\label{The research design's process conceptual diagram}
\end{figure}