Seee the paper at: https://arxiv.org/abs/1701.03441
Modified-LSTM
Simplifications of Gate Units for Long Short-term Memory (LSTM):
Case1): No input signal
Case2): No Input signal + No bias
Case3): No input signal + No hidden unit
Implementation environment: keras2.06 + Theano0.9 + wind10 + Cuda8.0 + cudnn5.1
This has been tested on numerous datasets including MNIST, IMDB, RNT, PennTree bank, etc.