Hidden Markov Models (HMMs). A hidden Markov model models a Markov process, but assumes that there is uncertainty in what state the system is in at any given time. A common metaphor is to think of the HMM as if the Markov Model were a mechanism hidden behind a curtain.
For the scientific journal, see Molecules (journal) . 3D (left and center) and 2D (right) representations of the terpenoid molecule atisane. A molecule (/ËmÉlÉªkjuËl/ from Latin moles mass) is an electrically neutral group of two or more atoms held together by chemical bonds.
Molecule refers to a kind of particle, and is therefore a microscopic concept. Even at the end of the 19th century, when compounds and their formulas had long been in use, some prominent chemists doubted that molecules (or atoms) were any more than a convenient model.