—Systems engineering (SE) and project management (PM) are two complementary disciplines that aim ... more —Systems engineering (SE) and project management (PM) are two complementary disciplines that aim at achieving a common goal. In order for systems engineers and project managers to communicate efficiently, there is a need for a common language that balances system performance, quality, stakeholder expectations and needs, cost, and schedule. We use Object Process Methodology (OPM) as the basis for Project-Product Lifecycle Management (PPLM), where SE and PM are complementary parts of an overarching system. Since the project plan is one of the first artefacts that both SE and PM professionals should agree on, we compared Gantt chart, a commonly used method, and a PPLM project plan. We present a three-stage comparative research, investigating how differences between a Gantt chart and an OPM model based PPLM project plan are perceived by mid-career systems engineers, who were graduate students in systems engineering academic programs. The outcomes indicate that the comprehension of information contained in the OPM model-based PPLM project plan is more easily grasped than the same information presented via the Gantt chart. The results suggest that PPLM has the potential to better clarify the intricate relationships between SE and PM involved in developing systems through projects. It can enable better understanding and communication between systems engineers and project managers, thereby improving decision-making, project outcomes, and product performance.
Object-Process Methodology – A Holistic Systems Paradigm
From the Foreword written by Edward Crawley
Object Process Methodology (OPM) includes a clear an... more From the Foreword written by Edward Crawley
Object Process Methodology (OPM) includes a clear and concise set of symbols that form a language enabling the expression of the system’s building blocks and how they relate to each other. It is a symbolic representation of the objects in a system and the processes they enable. OPM represents the two things that are inherent in a system: its objects and its processes. This duality is recognized throughout the community that studies systems, and sometimes goes by labels such as form/function, structure/function, and functional requirements/design parameters. Objects are what a system or product is. Processes are what a system does. Yet, it is remarkable that so few modeling frameworks explicitly recognize this duality. As a result, designers and engineers try to jump from the goals of a system (the requirements or the “program”) immediately to the objects. Serious theory in such disparate disciplines as software design, mechanical design and civil architectural design recognizes the value of thinking about processes in parallel with objects. Not only does OPM represent both objects and processes, but it also explicitly shows the connections between them. Object Process Methodology has another fundamental advantage – it represents the system simultaneously in a graphic representation and in a natural language. The two are completely interchangeable, and represent the same information. The advantage in this approach lies in appreciating the human limitation to the understanding of complexity. As systems become more complex, the primary barrier to success is the ability of the human designers and analysts to understand the complexity of the interrelationships. By representing the system in both textual and graphical form, the power of “both sides of the brain” – the visual interpreter and the language interpreter – is engaged. These are two of the strongest processing capabilities hard-wired into the human brain.
OPM allows a clear representation of the many important features of a system: its topological connections, its decomposition into elements and sub-elements, the interfaces among elements, and the emergence of function from elements. The builder or viewer of the model can view abstractions or zoom into some detail. One can see how specification migrates to implementation. These various views are invaluable when pondering the complexity of a real modern product system.
I have used OPM in my System Architecture course at MIT. It has proved an invaluable tool to professional learners in developing models of complex technical systems, such as automobiles, spacecraft and software systems. It allows an explicit representation of the form/function duality, and provides an environment in which various architectural options can be examined. Incorporating OPM into my subject has added the degree of rigor of analysis necessary to move the study of technical system architecture towards that of an engineering discipline.
One can anticipate that there will be many academic applications of OPM. I would consider using it in intermediate or advanced subjects in system engineering, product development, engineering design and software engineering. It is ideal for courses that demonstrate how various disciplines come together to form a multi-disciplinary product. Likewise, OPM can form the backbone of a corporate or enterprise modeling system for technical products. Such a representation would be especially valuable in conceptual and preliminary design, when much of the value, cost and risk of a product are established and only a few other modeling frameworks are available for decision support.
Edward F. Crawley Massachusetts Institute of Technology, Cambridge, Massachusetts
Web applications exhibit dynamic behaviour through such features as animation, rapidly changing p... more Web applications exhibit dynamic behaviour through such features as animation, rapidly changing presentations, and interactive forms. The growing complexity of web applications requires a rigorous modelling approach capable of clearly and explicitly addressing code mobility issues. While mobile agent systems and programming languages support the implementation of code mobility with features such as applets or mobile agents, existing system analysis and design methods lack the facilities to model code mobility satisfactorily. OPM/Web is an extension of object-process methodology (OPM) for modelling distributed systems and web applications that enables intuitive modelling of code mobility concepts in a single framework. We propose generic OPM/Web models for common code mobility design paradigms, including Remote Evaluation, Code-on-Demand, PUSH and Mobile Agents. An OPM/Web model of a mobile application that handles requests for Quality of Service over the internet exemplifies the use and advantages of modelling such systems in OPM/Web.
Models have traditionally been mostly either prescriptive, expressing the function, structure and... more Models have traditionally been mostly either prescriptive, expressing the function, structure and behavior of a system-to-be, or descriptive, specifying a system so it can be understood and analyzed. In this work, we offer a third kind—diagnostic models. We have built a model for assessing potential pediatric failure to thrive (FTT) during the perinatal stage. Although FTT is commonly found in young children and has been studied extensively, the exact etiology is often not clear. The ideal solution is for a pediatrician to input pertinent data and information in a single tool in order to obtain some assessment on the potential etiology. We present FTTell—an executable model-based medical knowledge aggregation and diagnosis tool, in which the qualitative considerations and quantitative parameters of the problem are modeled using a Methodical Approach to Executable Integrative Modeling (MAXIM)—an extended version of Object-Process Methodology (OPM) ISO 19450, focusing on the perinatal...
The generation of bimodal formal system specification documents that bi-directionally complement ... more The generation of bimodal formal system specification documents that bi-directionally complement graphics from natural language and vice versa through ObjectProcess Methodology (OPM) is presented. A sample of free text paragraphs from a document that describes the concept of Free Flight as part of the National Airspace System are converted to OPM specification. We then discuss the requirements of porting the OPM application to a Web environment, the challenges and the expected benefits.
As system complexity is on the rise, there is a growing need for standardized building blocks to ... more As system complexity is on the rise, there is a growing need for standardized building blocks to increase the likelihood of systems’ success. Conceptual modeling is the primary activity required for engineering systems to be understood, designed, and managed. Modern modeling languages enable describing the requirements and design of systems in a formal yet understandable way. These languages use stereotypes to standardize, clarify the model semantics, and extend the meaning of model elements. An Internet of things (IoT) system serves as an example to show the significant contributions of stereotypes to model construction, comprehension, error reduction, and increased productivity during design, simulation, and combined hardware–software system execution. This research emphasizes stereotype features that are unique to Object-Process Methodology (OPM) ISO 19450, differentiating it from stereotypes in other conceptual modeling languages. We present the implementation of stereotypes in ...
IFIP Advances in Information and Communication Technology, 2016
PLM tools mainly refer information systems based on a wide graph representing linked information.... more PLM tools mainly refer information systems based on a wide graph representing linked information. Such a PLM model is compatible with a metamodel often expressed in UML. UML graphics diagrams are paradigms to support sharing and understanding the concepts and relationships that must be supported by the PLM tool. Nevertheless instance diagrams contain so many objects that it is hard to present them in a holistic view that can be easily shared by collaborators. This paper presents a 3D approach to visualize an Object-Process Methodology (OPM) model, which provides a single holistic view of a complex system and supports sharing among collaborating parties. This approach has been applied to managing the complex information related to VISIONAIR-a European visualization infrastructure project, successfully enabling the management of 123 simultaneous projects.
INCOSE's definition of SE was compared to the aspirations set out in SE Vision 2025 for SE as it ... more INCOSE's definition of SE was compared to the aspirations set out in SE Vision 2025 for SE as it ought to be to address modern challenges. Doing this led us to three fundamental realisations. First, while "20 th century systems" were, for the most part, "deterministic" or nearly so, 21 st century systems are on the other hand increasingly non-deterministic, adaptive or "evolutionary". Second, while "20 th Century Systems Engineering Management" was implicitly based on a "command and control" paradigm, 21 st Century Systems Engineering, to be successful, will usually need to use a more collaborative leadership paradigm. And third, that while 20 th Century systems were largely "single systems", designed to "solve" specific problems, 21 st Century systems are almost invariably networked, and are parts of complex extended enterprises with multiple, often conflicting, stakeholder objectives, that are intimately related to complex societal challenges. We used elements of Soft Systems Methodology (SSM) to understand the implication and consequences of the paradigm shift implied by these realisations. A revised strawman definition of Systems Engineering is offered for consideration by INCOSE, showing the changes that would be required to take these and related factors into account. Systems Engineering is an interdisciplinary approach and means to enable the realization of successful systems. It focuses on defining customer needs and required functionality early in the development cycle, documenting requirements, then proceeding with design synthesis and system validation while considering the complete problem: Operations Cost & Schedule Test Disposal Performance Training & Support Manufacturing Systems Engineering integrates all the disciplines and specialty groups into a team effort forming a structured development process that proceeds from concept to production to operation. Systems Engineering considers both the business and the technical needs of all customers with the goal of providing a quality product that meets the user needs. With the publication of its Vision 2025, INCOSE demonstrates that Systems Engineering is relevant, and can add value, to all branches of engineering, allowing interdependencies in complex systems to be better understood and collaboration to be more productive.
Over the past decades, the definition of system has eluded researchers and practitioners. We revi... more Over the past decades, the definition of system has eluded researchers and practitioners. We reviewed over 100 definitions of system to understand the variations and establish a framework for a widely acceptable system definition or a family of system definitions. There is much common ground in different families of definitions of system, but there are also important and significant ontological differences. Some differences stem from the variety of belief systems and worldviews, while others have risen within particular communities. Both limit the effectiveness of system communities' efforts to communicate, collaborate, and learn from others' experience. We consider three ontological elements: (1) a worldview-based framework for typology of different system types and categories, (2) key system concepts that are fundamental to the various system types and categories, and (3) appropriate language for the target audience. In this work, we establish the ontological framework, list key concepts associated with different types of system, and point to a direction for agreeing on an integrated set of system definitions in a neutral language consistent with the framework. The definitions are compatible with both the realist and constructivist worldviews, covering real (physical, concrete) and conceptual (abstract, logical, informatical) systems, which are both human-made (artificial) and naturally-occurring, using language acceptable to a wide target stakeholder audience. The contribution of this paper is setting up an ontologically founded framework of system typologies, providing definitions for system, and identifying the issues involved in achieving a widely accepted definition or family of definitions of system.
Over the past decades, a common definition of the term system has eluded researchers and practiti... more Over the past decades, a common definition of the term system has eluded researchers and practitioners alike. We reviewed over 100 current and historical definitions of system in an effort to understand perspectives and to propose the most comprehensive definition of this term. There is much common ground in different families of definition of system, but there are also important and significant differences. Some stem from different belief systems and worldviews, while others are due to a pragmatic desire to establish a clear definition for system within a particular community, disregarding wider considerations. In either case, it limits the effectiveness of various system communities' efforts to communicate, collaborate, and learn from the experience of other communities. We discovered that by considering a wide typology of systems, Bertalanffy's General Systems Theory provides a basis for a general, self-consistent sensible framework, capable of accommodating and showing t...
2016 Annual IEEE Systems Conference (SysCon), 2016
Joint architecting, design, and simulation of operational-functional requirements and scenarios o... more Joint architecting, design, and simulation of operational-functional requirements and scenarios on the one hand and system functionality and technological requirements on the other hand is a common challenge in systems engineering. We propose a model-based systems engineering approach that addresses this challenge. The confusion between operational and functional behavior stems from systems engineers' inherent tendency to adopt a system-centric perspective and employ modeling techniques that are inadequate for the task at hand. Functional models provide a biased perspective on the overarching operational context, while business-process-oriented models provide partial coverage of the system's architecture-its structure-behavior combination. The problem intensifies when the operational scenario is indefinite and dependent on responsive system behavior and when the operational scenario consists of the utilization of functionality in multiple systems. Operational mission management in various domains utilizes planning, execution, and control functionality in several systems, and copes with the operational-functional distinction.
Joint architecting, design, and simulation of operational-functional requirements and scenarios o... more Joint architecting, design, and simulation of operational-functional requirements and scenarios on the one hand and system functionality and technological requirements on the other hand is a common challenge in systems engineering. We propose a model-based systems engineering approach that addresses this challenge. The confusion between operational and functional behavior stems from systems engineers' inherent tendency to adopt a system-centric perspective and employ modeling techniques that are inadequate for the task at hand. Functional models provide a biased perspective on the overarching operational context, while business-process-oriented models provide partial coverage of the system's architecture—its structure-behavior combination. The problem intensifies when the operational scenario is indefinite and dependent on responsive system behavior and when the operational scenario consists of the utilization of functionality in multiple systems. Operational mission managem...
Conceptual modeling is an important initial stage in the lifecycle of engineered systems. It is a... more Conceptual modeling is an important initial stage in the lifecycle of engineered systems. It is also highly instrumental in studying existing unfamiliar systems-the focus of scientific inquiry. Conceptual modeling methodologies convey key qualitative system aspects, often at the expense of suppressing quantitative ones. We present and assess two approaches for solving this computational simplification problem, defined below, by combining Object Process Methodology (OPM), the new ISO/PAS 19450, with MATLAB or Simulink without compromising the holism and simplicity of the OPM conceptual model. The first approach, AUTOMATLAB, expands the OPM model to a full-fledged MATLAB-based simulation. In the second approach, OPM Computational Subcontractor, computation-enhanced functions replace low-level processes of the OPM model with MATLAB or Simulink models. We demonstrate the OPM Computational Subcontractor on a radar system computation. Experimenting with students on a model of an online shopping system with and without AUTOMATLAB has indicated important benefits of employing this computation layer on top of the native conceptual OPM model.
In Chapter 2, we started developing the ATM system, and were exposed to OPDs, the graphic facet o... more In Chapter 2, we started developing the ATM system, and were exposed to OPDs, the graphic facet of OPM. Spoken or written language is the modality of OPM that is complementary to the graphics. Winograd and Flores (1987) noted: “Nothing exists except through language. In saying that some “thing” exists (or that it has some property) we have brought it into a domain of articulated objects and qualities that exist in language.” Indeed, language greatly enhances our ability to understand systems and communicate our understanding to others. In this chapter, we introduce the Object-Process Language (OPL) and show the equivalence between graphic specification through OPDs and natural language specification through OPL sentences and paragraphs. We will add the language element to the set of OPDs we started developing in Chapter 2. We will then proceed with the ATM case study, adding more detailed OPDs and their corresponding OPL paragraphs.
Data warehouse modeling is a complex task, which involves knowledge of business processes of the ... more Data warehouse modeling is a complex task, which involves knowledge of business processes of the domain of discourse, understanding the structural and behavioral system's conceptual model, and familiarity with data warehouse technologies. The suitability of current data warehouse modeling methods for large-scale systems is questionable, as they require multiple manual actions to discover measures and relevant dimensional entities and they tend to disregard the system's dynamic aspects. We present an Object-process-based Data Warehouse Construction (ODWC) method that overcomes these limitations of existing methods by utilizing the operational system conceptual model to construct a corresponding data warehouse schema. We specify the ODWC method, apply it on a case study, evaluate it, and compare it to existing methods.
Machine Vision Applications in Character Recognition and Industrial Inspection (Proceedings Volume)
* Available as a photocopy reprint only. Allow two weeks reprinting time plus standard delivery t... more * Available as a photocopy reprint only. Allow two weeks reprinting time plus standard delivery time. No discounts or returns apply. ... Standard delivery in the US is 7 to 10 business days and outside the US delivery is 4 to 6 weeks or longer. For further details, please see shipping policy. ... Listed below are the papers found in this volume. Click the paper title to view an abstract or to order an individual paper.
We envision that Systems Engineering (SE) can be transformed into a truly transdisciplinary disci... more We envision that Systems Engineering (SE) can be transformed into a truly transdisciplinary discipline – a foundational meta-discipline that supports and enables collaboration between all the disciplines that should be involved in conceiving, building, using and evolving a system so that it will continue to be successful and fit for purpose as time passes. SE can be applied in different ways depending on the situation and how well current SE process patterns are matched to the problem in hand. We identify four elements of this new transdisciplinary framework: SE Tenets; SE Approach; SE Process; and SE Toolbox. We suggest that the use of SE then needs to be considered in three domains: problem space, solution space, and transformation space that helps us along the development-delivery-evolution trajectory. We propose twelve SE tenets and show how they should be applied in these three domains. We perceive that even though all elements of the current SE Process can be justified in terms of the twelve tenets applied to these three domains, the current commonly used, standardized SE Process is not suitable for all situations requiring an SE Approach or an application of the SE Tenets. We claim that the framework presented in this paper can act as a unifying structure that facilitates the evolution of Systems Engineering from the current focus on a " standardized " process model suited to a particular class of problem, to a more agile and capable " transdiscipline " that will provide an enabling construct for more successful collaborations that can better deal with a wider range of complicated, complex and chaotic problem situations.
The cyber-physical gap (CPG) is the difference between the 'real' state of the world and the way ... more The cyber-physical gap (CPG) is the difference between the 'real' state of the world and the way the system perceives it. This discrepancy often stems from the limitations of sensing and data collection technologies and capabilities, and is inevitable at some degree in any cyber-physical system (CPS). Ignoring or misrepresenting such limitations during system modeling, specification, design, and analysis can potentially result in systemic misconceptions, disrupted functionality and performance, system failure, severe damage, and potential detrimental impacts on the system and its environment. We propose CPG-Aware Modeling & Engineering (CPGAME), a conceptual model-based approach to capturing, explaining, and mitigating the CPG. CPGAME enhances the systems engineer's ability to cope with CPGs, mitigate them by design, and prevent erroneous decisions and actions. We demonstrate CPGAME by applying it for modeling and analysis of the 1979 Three Miles Island 2 nuclear accident, and show how its meltdown could be mitigated. We use ISO-19450:2015-Object Process Methodology as our conceptual modeling framework.
The Machine Drawing Understanding System (MDUS) is an experimental CAD conversion system aimed at... more The Machine Drawing Understanding System (MDUS) is an experimental CAD conversion system aimed at realizing the entire process of understanding mechanical engineering drawings, from scanning to three-dimensional (3-D) reconstruction. This paper describes the structure, algorithms and current performance of MDUS. The modular structure of the system provides for further improvements and makes it an ideal workbench for researchers wishing to test their own algorithms and incorporate them into the system.
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Object Process Methodology (OPM) includes a clear and concise set of symbols that form a language enabling the expression of the system’s building blocks and how they relate to each other. It is a symbolic representation of the objects in a system and the processes they enable.
OPM represents the two things that are inherent in a system: its objects and its processes. This duality is recognized throughout the community that studies systems, and sometimes goes by labels such as form/function, structure/function, and functional requirements/design parameters. Objects are what a system or product is. Processes are what a system does. Yet, it is remarkable that so few modeling frameworks explicitly recognize this duality. As a result, designers and engineers try to jump from the goals of a system (the requirements or the “program”) immediately to the objects. Serious theory in such disparate disciplines as software design, mechanical design and civil architectural design recognizes the value of thinking about processes in parallel with objects. Not only does OPM represent both objects and processes, but it also explicitly shows the connections between them.
Object Process Methodology has another fundamental advantage – it represents the system simultaneously in a graphic representation and in a natural language. The two are completely interchangeable, and represent the same information. The advantage in this approach lies in appreciating the human limitation to the understanding of complexity. As systems become more complex, the primary barrier to success is the ability of the human designers and analysts to understand the complexity of the interrelationships. By representing the system in both textual and graphical form, the power of “both sides of the brain” – the visual interpreter and the language interpreter – is engaged. These are two of the strongest processing capabilities hard-wired into the human brain.
OPM allows a clear representation of the many important features of a system: its topological connections, its decomposition into elements and sub-elements, the interfaces among elements, and the emergence of function from elements. The builder or viewer of the model can view abstractions or zoom into some detail. One can see how specification migrates to implementation. These various views are invaluable when pondering the complexity of a real modern product system.
I have used OPM in my System Architecture course at MIT. It has proved an invaluable tool to professional learners in developing models of complex technical systems, such as automobiles, spacecraft and software systems. It allows an explicit representation of the form/function duality, and provides an environment in which various architectural options can be examined. Incorporating OPM into my subject has added the degree of rigor of analysis necessary to move the study of technical system architecture towards that of an engineering discipline.
One can anticipate that there will be many academic applications of OPM. I would consider using it in intermediate or advanced subjects in system engineering, product development, engineering design and software engineering. It is ideal for courses that demonstrate how various disciplines come together to form a multi-disciplinary product.
Likewise, OPM can form the backbone of a corporate or enterprise modeling system for technical products. Such a representation would be especially valuable in conceptual and preliminary design, when much of the value, cost and risk of a product are established and only a few other modeling frameworks are available for decision support.
Edward F. Crawley
Massachusetts Institute of Technology,
Cambridge, Massachusetts
Papers by Dov Dori