perl dtd2xsd.pl [option...] [file]
  -alias
    enables special type aliases (default <b>off</b>)
  -prefix p
    specify namespace prefix
  -ns http://www.w3.org/namespace/
    specify namespace URI
  -pcdata
    treat content models of just (#PCDATA) as string, not mixed content
  -simpletype pattern base
    treat parameter entities whose name match this pattern
    as simple datatypes derived from this base type
  -attrgroup pattern
    treat parameter entities whose name match this pattern
    as attribute groups
  -modelgroup pattern
    treat parameter entities whose name match this pattern
    as model groups
  -substgroup pattern
    treat parameter entities whose name match this pattern
    as substitution groups (must be a | group, therefore)
  -mapfile file
    read the given file and process its contents for mappings

The mapping file consists of a series of lines with directives that are 
interpreted just like the corresponding command line arguments. Handy if you
have a set of related DTDs to convert.

Alias pattern typeAlias
SimpleType pattern typeName
ModelGroup pattern
AttrGroup pattern
SubstGroup pattern
PCDATA typeAlias

The PCDATA directive gives the type alias to use instead of string for content
models of just (#PCDATA), provided the -pcdata flag is enabled.

The difference between aliases and simple types is that a simple type
declaration will be created for the latter, and references with include the
proper namespace prefix, whereas aliases will just be substituted as is.

Example:
Alias NUMBER nonNegativeInteger
Alias Date date
Alias Float float
SimpleType SKU string
SimpleType AddressLine string