Contact Information

Research Interests

I am interested in multidisciplinary analysis including modeling and simulation, information modeling, and optimization of product systems.  I am researching ways in which current systems engineering methods can be augmented through an upper-level, formal organization scheme to better manage system design complexity by improving the integration among stakeholder concerns.

A model of a system is usually composed for each system stakeholder, whose concern can be independent of other concerns.  Particular product attributes for a system architecture are addressed by the different stakeholder concerns, such as dynamic behavior, reliability behavior, and cost behavior.  The behaviors of these attributes are predicted by individual models that capture these individual aspects of a system.  It is in this regard that the stakeholder concerns, which address specific attributes, are regarded as system aspects.

Systems modeling is a complex issue, as there are many levels of systems and of abstraction; there are even systems of systems.  Within the applied domain of fluid power systems, I am researching how hydrualic system architectures can be modeled as a composition of models of the components and subsystems that comprise a hydraulic system.  The application is directed towards the hydraulic system of an excavator.

Components of the excavator system are combined with different system aspects by the current approach of Multi-Aspect Component Models (MAsCoMs).  This research is funded by NSF's Fluid Power ERC, the Center for Compact and Efficient Fluid Power http://www.ccefp.org

Multi-Aspect Component Model Framework

Each model of a MAsCoM is part of the set of models that each MAsCoM container owns.  Each model in this set is linked to a formal structure model of a component (in a particular domain, at a particular level of abstraction), and to the aspects that describe the different perspectives that the model represents.

Uses of the Framework

A key motivation to the interest of improving the integration of stakeholder concerns about system aspects is the ability to provide system-level tradeoffs among multiple perspectives.  These perspectives, which are system aspects, include dynamic and steady-state behavior, reliability, cost, and many others. 

To support system analysis models and their capability to provide such system tradeoffs among different aspects, models must be characterized in such a way as to provide the true semantics, or meaning, behind the development of each model.  In this way, models are reusable by such a characterization, and can be saved for future use.  Furthermore, in order to provide an analysis capable of demonstrating a system-level tradeoff, system models must incorporate aspects among which a  trade-off is desired.  This requires interoperability among different aspects, which is achieved by composing the system models from component models that include the desired aspects.

Composition of system models among different aspects is introduced in the topic of Multi-Aspect Component Models.  A paper on the subject can be viewed in Publications.

Publications

Author -  "Multi-Aspect Component Models:  A Framework for Model Reuse in SysML" IDETC/CIE 2008, Brooklyn, NY   -  Link to paper (pdf)        

Jobe, J. M., Paredis, C. J. J. and Johnson, T. A., “Multi-Aspect Component Models: A Framework for Model Reuse in SysML,” in 2008 ASME International Design Engineering Technical Conferences and Computers in Information Engineering Conference, Brooklyn, NY: ASME, 2008.

Coauthor -  "Modeling Continuous System Dynamics in SysML" IMECE2007, Seattle, WA - Link to paper (pdf)        

Johnson, T. A., Paredis, C. J. J., Burkhart, R. and Jobe, J. M., "Modeling Continuous System Dynamics in SysML," in 2007 ASME International Mechanical Engineering Congress and Exposition, Seattle, WA: ASME, 2007.

Class Reports

• Jobe, J.M., Messer, M., 2006, "Optimization of an Opto-electronic Communications System." ME6103 Optimization in Engineering Design Class Report, Georgia Institute of Technology, Atlanta, GA.
• Jobe, J.M., 2007, "Modeling System Reliability via Modular Reusable Models in SysML" AE4803 Reliability, Engineering and Systems Safety Term Paper, Georgia Institute of Technology, Atlanta, GA.  Link to paper (pdf)
• Jobe, J.M., Cochran, S., Majeed, W., Andersch, P., 2007, "Frequency Estimation for Use in Adaptive Input Shaping" (Using the Recursive Least Squares Algorithm) ME6404 Advanced Control System Design and Implementation Project Paper, Georgia Institute of Technology, Atlanta, GA.  Link to paper (word doc)

Class Projects

• ME6105 Modeling and Simulation- Compact Rescue Crawler Link to website
• ME6405 Mechatronics- Pneumatic Bubble Writer Link to website (Student Projects - Fall 05)

Master of Science Thesis (In progress)

I am researching ways in which graph transformation rules and system architecture requirements can be used to create computer-automated composition of system models about different aspects.  Particularly, I am working on the ability to create meaningful system reliability models within the Multi-Aspect Component Model framework to achieve the ability for automated composition of such models.  The availability of reliability data will improve the abilities of system trade-offs among multiple system architectures with respect to the reliability aspect.

Other Information

Functional Resume (most up to date)

General Resume (GT ME website)

Hobbies Page

Collaborate

Whiteboard me (Research Colleagues only, password protected)

Presentations.

Link to GT FP website when finished.