David Lorge Parnas (born February 10, 1941) is a

Canadian Canadians () are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of their being ''C ...

early pioneer of

software engineering Software engineering is a branch of both computer science and engineering focused on designing, developing, testing, and maintaining Application software, software applications. It involves applying engineering design process, engineering principl ...

, who developed the concept of

information hiding In computer science, information hiding is the principle of segregation of the ''design decisions'' in a computer program that are most likely to change, thus protecting other parts of the program from extensive modification if the design decisio ...

modular programming Modular programming is a software design technique that emphasizes separating the functionality of a program into independent, interchangeable modules, such that each contains everything necessary to execute only one aspect or "concern" of the d ...

, which is an important element of

object-oriented programming Object-oriented programming (OOP) is a programming paradigm based on the concept of '' objects''. Objects can contain data (called fields, attributes or properties) and have actions they can perform (called procedures or methods and impl ...

today. He is also noted for his advocacy of precise documentation.

Life

Parnas earned his PhD at

Carnegie Mellon University Carnegie Mellon University (CMU) is a private research university in Pittsburgh, Pennsylvania, United States. The institution was established in 1900 by Andrew Carnegie as the Carnegie Technical Schools. In 1912, it became the Carnegie Institu ...

electrical engineering Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...

. Parnas also earned a professional engineering license in Canada and was one of the first to apply traditional engineering principles to software design. He worked there as a professor for many years. He also taught at the

University of North Carolina at Chapel Hill The University of North Carolina at Chapel Hill (UNC, UNC–Chapel Hill, or simply Carolina) is a public university, public research university in Chapel Hill, North Carolina, United States. Chartered in 1789, the university first began enrolli ...

(U.S.), at the

Department of Computer Science Computer science is the study of computation, information, and automation. Computer science spans theoretical disciplines (such as algorithms, theory of computation, and information theory) to applied disciplines (including the design and ...

of the

Technische Universität Darmstadt The Technische Universität Darmstadt (official English name Technical University of Darmstadt, sometimes also referred to as Darmstadt University of Technology), commonly known as TU Darmstadt, is a research university in the city of Darmsta ...

(Germany), the

University of Victoria The University of Victoria (UVic) is a public research university located in the municipalities of Oak Bay, British Columbia, Oak Bay and Saanich, British Columbia, Canada. Established in 1903 as Victoria College, British Columbia, Victoria Col ...

(

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

, Canada), Queen's University in

Kingston, Ontario Kingston is a city in Ontario, Canada, on the northeastern end of Lake Ontario. It is at the beginning of the St. Lawrence River and at the mouth of the Cataraqui River, the south end of the Rideau Canal. Kingston is near the Thousand Islands, ...

McMaster University McMaster University (McMaster or Mac) is a public research university in Hamilton, Ontario, Canada. The main McMaster campus is on of land near the residential neighbourhoods of Ainslie Wood, Ontario, Ainslie Wood and Westdale, Ontario, Westd ...

Hamilton, Ontario Hamilton is a port city in the Canadian Provinces and territories of Canada, province of Ontario. Hamilton has a 2021 Canadian census, population of 569,353 (2021), and its Census Metropolitan Area, census metropolitan area, which encompasses ...

, and

University of Limerick University of Limerick (UL) () is a Public university, public research university institution in Limerick, Republic of Ireland, Ireland. Founded in 1972, as the National Institute for Higher Education, Limerick, it became a university in Septemb ...

(Ireland). David Parnas received a number of awards and honors: * ACM "Best Paper" Award, 1979 *

Norbert Wiener Award for Social and Professional Responsibility The Norbert Wiener Award for Social and Professional Responsibility was established in 1987 in honor of Norbert Wiener to recognize contributions by computer professionals to socially responsible use of computers. It was awarded annually by CPSR, ...

, 1987 * Two "Most Influential Paper" awards

International Conference on Software Engineering The International Conference on Software Engineering (ICSE) is one of the largest annual software engineering conferences. It has an 'A*' rating in thRankingsof thComputing Research and Education Association of Australasia (CORE)and an 'A1' rati ...

, 1991 and 1995 *

Doctor honoris causa An honorary degree is an academic degree for which a university (or other degree-awarding institution) has waived all of the usual requirements. It is also known by the Latin phrases ''honoris causa'' ("for the sake of the honour") or ''ad hono ...

of the Computer Science Department,

ETH Zurich ETH Zurich (; ) is a public university in Zurich, Switzerland. Founded in 1854 with the stated mission to educate engineers and scientists, the university focuses primarily on science, technology, engineering, and mathematics. ETH Zurich ran ...

, Switzerland, 1986 *

Fellow A fellow is a title and form of address for distinguished, learned, or skilled individuals in academia, medicine, research, and industry. The exact meaning of the term differs in each field. In learned society, learned or professional society, p ...

of the

Royal Society of Canada The Royal Society of Canada (RSC; , SRC), also known as the Academies of Arts, Humanities, and Sciences of Canada (French: ''Académies des arts, des lettres et des sciences du Canada''), is the senior national, bilingual council of distinguishe ...

, 1992 *

of the

Association for Computing Machinery The Association for Computing Machinery (ACM) is a US-based international learned society for computing. It was founded in 1947 and is the world's largest scientific and educational computing society. The ACM is a non-profit professional membe ...

, 1994 *

of the

Louvain School of Engineering The Louvain School of Engineering or ''École polytechnique de Louvain'' (EPL) is a faculty of the University of Louvain, Belgium, founded in 1864. Known as the Faculty of Applied Sciences (''Faculté des sciences appliquées'') prior to 2008, it ...

University of Louvain UCLouvain (or Université catholique de Louvain , French for Catholic University of Louvain, officially in English the University of Louvain) is Belgium's largest French-speaking university and one of the oldest in Europe (originally establishe ...

(UCLouvain), Belgium, 1996 * ACM

SIGSOFT The Association for Computing Machinery's Special Interest Group on Software Engineering provides a forum for computing professionals from industry, government and academia to examine principles, practices, and new research results in software ...

's "Outstanding Research" award, 1998 *

IEEE Computer Society IEEE Computer Society (commonly known as the Computer Society or CS) is a technical society of the Institute of Electrical and Electronics Engineers (IEEE) dedicated to computing, namely the major areas of hardware, software, standards and people ...

's 60th Anniversary Award, 2007 *

of the Faculty of Informatics,

University of Lugano A university () is an institution of tertiary education and research which awards academic degrees in several academic disciplines. ''University'' is derived from the Latin phrase , which roughly means "community of teachers and scholars". Univ ...

, Switzerland, 2008 *

of the

Gesellschaft für Informatik The German Informatics Society (GI) () is a German professional society for computer science, with around 20,000 personal and 250 corporate members. It is the biggest organized representation of its kind in the German-speaking world. History The ...

, 2008 *

of the

Institute of Electrical and Electronics Engineers The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines. The IEEE has a corporate office ...

(

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) organization, 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines. The IEEE ...

), 2009 *

of the

Vienna University of Technology TU Wien () is a public research university in Vienna, Austria. The university's teaching and research are focused on engineering, computer science, and natural sciences. It currently has about 28,100 students (29% women), eight faculties, and ...

(Dr. Tech.H.C.), Vienna Austria, 2011

Work

Modular design

modular design Modular design, or modularity in design, is a design principle that subdivides a system into smaller parts called ''modules'' (such as modular process skids), which can be independently created, modified, replaced, or exchanged with other modules ...

, his double dictum of high cohesion within modules and loose

coupling A coupling is a device used to connect two shafts together at their ends for the purpose of transmitting power. The primary purpose of couplings is to join two pieces of rotating equipment while permitting some degree of misalignment or end mo ...

between modules is fundamental to modular design in software. However, in Parnas's seminal 1972 paper ''On the Criteria to Be Used in Decomposing Systems into Modules'', this dictum is expressed in terms of

, and the terms ''cohesion'' and ''coupling'' are not used.

Technical activism

Dr Parnas took a public stand against the US

Strategic Defense Initiative The Strategic Defense Initiative (SDI) was a proposed missile defense system intended to protect the United States from attack by ballistic nuclear missiles. The program was announced in 1983, by President Ronald Reagan. Reagan called for a ...

(also known as "Star Wars") in the mid 1980s, arguing that it would be impossible to write an application of sufficient quality that it could be trusted to prevent a nuclear attack. He has also been in the forefront of those urging the professionalization of "

" (a term that he characterizes as "an unconsummated marriage"). Dr. Parnas is also a heavy promoter of ethics in the field of software engineering.

Stance on academic evaluation methods

Parnas has joined the group of scientists which openly criticize the number-of-publications-based approach towards ranking academic production. On his November 2007 paper ''Stop the Numbers Game'', he elaborates on several reasons on why the current number-based academic evaluation system used in many fields by universities all over the world (be it either oriented to the amount of publications or the amount of quotations each of those get) is flawed and, instead of contributing to scientific progress, it leads to knowledge stagnation.

Bibliography

References

External links

McMaster University (Hamilton, Ontario, Canada)University of Limerick profile
broken 2013-4-26 an
CV
broken 2013-4-26
IEEE Computer Society's 60th Anniversary Award
* {{DEFAULTSORT:Parnas, David 1941 births Living people People from Plattsburgh, New York American computer scientists Carnegie Mellon University College of Engineering alumni Carnegie Mellon University faculty Formal methods people 1994 fellows of the Association for Computing Machinery Academic staff of McMaster University Canadian software engineers Software engineering researchers Academics of the University of Limerick Scientists from New York (state) Academic staff of Technische Universität Darmstadt

Life

Work

Modular design

Technical activism

Stance on academic evaluation methods

Bibliography

See also

References

Further reading

External links