  In this paper, the stability analysis of quaternion-valued neural networks
(QVNNs) with both leakage delay and additive time-varying delays is proposed.
By employing the Lyapunov-Krasovskii functional method and fully considering
the relationship between time-varying delays and upper bounds of delays, some
sufficient criteria are derived based on reciprocally convex method and several
inequality techniques. The stability criteria are established in two forms:
quaternion-valued linear matrix inequalities (QVLMIs) and complex-valued linear
matrix inequalities (CVLMIs), in which CVLMIs can be directly resolved by the
Yalmip toolbox in MATLAB. Finally, an illustrative example is presented to
demonstrate the validity of the theoretical results.
