Portman Estate area remained largely residential, attracting the prosperous middle class who wanted to live near the centre of London. There were also mews for tradesmen and servants. At the southwest corner of the Estate, where Marble Arch now stands, was the Tyburn gallows, London’s principal place of public execution until 1783. Development of the area north of the Marylebone Road around Dorset Square continued after 1815, and to the North West in Lisson Green, workers’ cottages were built from 1820 to 1840. Many of the original Georgian houses north of Portman Square were redeveloped as mansion blocks, which were let on
Execution model Execution model An execution model specifies how work takes place. Every programming language has an execution model, which is specified as part of the language specification, and is implemented as part of the language implementation. The details in the specification of an execution model cover things such as what is an indivisible unit of work, and what are the constraints on the order in which those units of work take place. For example, the addition operation is an indivisible unit of work in many languages, and in sequential languages such units of work are constrained to take place one after