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.
A molecule is a particle made up of two or more atoms that are chemically bonded together; the number of atomic nuclei making up a molecule is a determinate number. For example, HCl (g) is a molecule made of one hydrogen atom bonded to one chlorine atom. It is made of two atoms and is called a diatomic molecule. A crystal of NaCl (s) is not a molecule: it is an ionic lattice made up of an indeterminate number of atoms. Carbon dioxide is a molecule made of two oxygen atoms bonded to a carbon atom. It contains three atoms and is called a triatomic molecule. Silicon dioxide - best known as quartz - exists as an large covalent network made up of an indeterminate number of atoms.