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Conrad Bock (Fed)

Conrad Bock is a Computer Scientist Systems in NIST’s Communications Technology Lab performing research in Smart Connected Manufacturing Systems.  He is currently project leader for integrating systems engineering and analysis models (SAI), leading research and standardization in interoperability between modeling languages used in systems engineering and specialized engineering disciplines, such as 1D simulation and logical verification of behavior models.

He specializes in engineering information language formalization, focusing on representation of system behavior and assembly, and facilitating capture of implicit knowledge. His work leverages ontology-based language development, as in OWL and the Process Specification Language (PSL), a first-order axiomitization of processes supporting automated consistency checking of rules against processes. He used PSL to develop the first standard formalization of UML.  This led to his development of an ontology modeling architecture now used as the basis for a major upgrade to the Systems Modeling Language (SysML), the most widely-used graphical language for systems engineering, currently being prepared for Object Management Group (OMG).

Mr. Bock is a past chair of the OMG Revision Task Force for SysML, versions 1.3 and 1.4, and one of the primary contributors to the Unified Modeling Language (UML) at OMG, most widely-used graphical language for software and the basis for SysML.

He was a significant contributor to a major upgrade to the Business Process Model and Notation (BPMN), a with improvements for modeling interaction between businesses or parts of a business. He led the development of semantics for public process modeling, and integrating interactions with internal business processes. He also led development of a UML extension for BPMN Processes, to improve interoperability between process and software modeling.


Mr. Bock received two U.S. Department of Commerce Bronze Medals and an International Council on Systems Engineering Outstanding Service Award for work on developing and formalizing systems engineering information languages.


Selected Publications

Ontological Behavior Modeling

Conrad E. Bock, James Odell
This article gives an example of improving the effectiveness of behavior modeling languages using ontological techniques. The techniques are applied to

UML 2 Composition Model

Conrad E. Bock
The composition model in the Unified Modeling Language, version 2, is a major upgrade to the familiar black diamond composition of earlier versions. It supports

Evaluating Reasoning Systems

Conrad Bock, Michael Gruninger, Donald E. Libes, Joshua Lubell, Eswaran Subrahmanian
A review of the literature on evaluating reasoning systems reveals that it is a very broad area with wide variation in depth and breadth of research on metrics

UML 2 Activity and Action Models

Conrad E. Bock
This is the first in a series introducing the activity model in the Unified Modeling Language, version 2 (UML 2), and how it integrates with the action model [1

PSL: A Semantic Domain for Flow Models

Conrad Bock, Michael Gruninger
Flow models underlie popular programming languages and many graphical behavior specification tools. However, their semantics is typically ambiguous, causing

Ontological Product Modeling for Collaborative Design

Conrad E. Bock, XuanFang Zha, Hyo-won Suh, Jae H. Lee
This paper shows how to combine ontological and model-based techniques in languages that facilitate collaborative design exploration. The proposed approach uses


SysML Models for Discrete Event Logistics Systems

Timothy A. Sprock, Conrad E. Bock
System models and model-based engineering methods have the promise of transforming the way that industrial engineers interact with production and logistics
Created October 9, 2019, Updated December 8, 2022