Larry Howard

Introducing embedded software and systems education and advanced learning technology in an engineering curriculum

Embedded software and systems are at the intersection of electrical engineering, computer engineering, and computer science, with, increasing importance, in mechanical engineering. Despite the clear need for knowledge of systems modeling and analysis (covered in electrical and other engineering disciplines) and analysis of computational processes (covered in computer science), few academic programs have integrated the two disciplines into a cohesive program of study. This paper describes the efforts conducted at Vanderbilt University to establish a curriculum that addresses the needs of embedded software and systems. Given the compartmentalized nature of traditional engineering schools, where each discipline has an independent program of study, we have had to devise innovative ways to bring together the two disciplines. The paper also describes our current efforts in using learning technology to construct, manage, and deliver sophisticated computer-aided learning modules that can supplement the traditional course structure in the individual disciplines through out-of-class and in-class use.

OpenMETA: A Model- and Component-Based Design Tool Chain for Cyber-Physical Systems

Model- and component-based design have yielded dramatic increase in design productivity in several narrowly focused homogeneous domains, such as signal processing, control and aspects of electronic design. However, significant impact on the design and manufacturing of complex cyber-physical systems (CPS) such as vehicles has not yet been achieved. This paper describes challenges of and solution approaches to building a comprehensive design tool suite for complex CPS. The primary driver for the OpenMETA tool chain was to push the boundaries of the “correct-by-construction” principle to decrease significantly the costly design-build-test-redesign cycles in design flows. In the discussions we will focus on the impact of heterogeneity in modeling CPS. This challenge is compounded by the need for rapidly evolving the design flow by changing/updating the selection of modeling languages, analysis and verification tools and synthesis methods. Based on our experience with the development of OpenMETA and with the evaluation of its performance in a complex CPS design challenge we argue that the current vertically integrated, discipline-specific tool chains for CPS design need to be complemented with horizontal integration layers that support model integration, tool integration and design process integration. This paper will examine the OpenMETA technical approach to construct the new integration layers, provides and overview of the technical framework we established for their implementation and summarize our experience with their application.

An evolvable tri-reasoner IVHM system

Meeting the challenges of decreasing operational costs and increasing operational readiness for future aircraft will require a systemic approach to integrated vehicle health management (IVHM). Realizing such an approach will involve synergistic deployments of component health monitoring technologies, as well as integrated, model-based reasoning capabilities for the interpretation of the monitor outputs. Further, it will involve the introduction of learning technologies to support the continuous improvement of the knowledge enabling these reasoning capabilities. Finally, it will involve organizing these elements into an architecture that governs integration and interoperation-within the VHM system, between its on-board elements and their ground-based support functions, and between the VHM system and external maintenance and operations functions. We present and discuss the architecture for an evolvable tri-reasoner integrated VHM system, its particular elements and their interrelationships.

Adaptive learning technologies for bioengineering education

Learning technologies employed both inside and outside the classroom are increasingly influencing the nature of teaching and learning. Web-based learning technologies are enabling powerful possibilities for learning activities outside the classroom, both in preparation for in-class activities and in following them up. Of particular importance among these possibilities is the opportunity to address learners as individuals, assessing their strengths and weaknesses and adapting learning activities in response. Over the past few years we have been developing and maturing learning technologies that target these aims in the context of the National Science Foundations VaNTH (Vanderbilt University; Northwestern University; University of Texas at Austin; and Health, Science and Technology at Harvard/MIT) Engineering Research Center (ERC). In this article we describe these technologies and discuss their roles in bioengineering education. In pursuing adaptive learning technologies for VaNTH, our primary motivation has been to make the means for authoring such activities accessible to bioengineering educators while providing enough expressive power to enable ambitious applications and the ability to incrementally acquire the needed skills. To address this aim we have created an authoring technology called the courseware authoring and packaging environment (CAPE).

An algorithm for diagnostic reasoning using TFPG models in embedded real-time applications

Embedded diagnostic reasoners require compact modeling representations and efficient reasoning algorithms given limited available computational resources. Timed failure propagation graphs (TFPG) are compact representations used to model failure causes and progressions of conditions that are symptoms of failure occurrence, together with the temporality and likelihood of these symptom progressions and the observation of some of the aberrant conditions. Algorithms for design-time diagnosability analysis using TFPG models have previously been reported, but these algorithms have different design objectives leading to different computational strategies and optimization criteria. This paper presents and discusses an algorithm specifically designed for efficient failure isolation based on reported observations of abnormal conditions that is suitable for use in embedded real-time applications.

Reflecting on online learning designs using observed behavior

Educators, as designers of resources, experiences, and environments for learning, make judgments and assumptions about learners and how design choices will affect them. While some uncertainties can be resolved through the design process, others must be addressed experientially, through action (implementation or enactment) punctuated by reflection. Online learning designs, since they are often motivated by broad, asynchronous accessibility, offer both unique challenges and opportunities for design reflection. The challenges tend to concern greater diversity among larger learner populations, and therefore a need to account for greater potential variance in learner experiences. The opportunities arise from the nature of the medium, where use can be passively observed through interactions between learners and the learning environment. In this paper, we address the use of observed behavior as a lens for design reflection on a large corpus of online learning resources focusing on cybersecurity for adult learners.

Towards a Generic Cloud-Based Modeling Environment

This paper is aimed at presenting a concept of a flexible diagramming framework for building engineering and educational applications. The framework was designed to serve as a platform for online services and collaborative environments where users typically work on remotely stored, shared data through a browser-based user interface. The paper summarizes the common requirements towards such services, overviews related approaches and gives insights into some design challenges through the analysis of use-cases. The design problem is examined from a user-centered view: the key motivation of our research is to find innovative, possibly device-independent solutions that enable seamless user experiences. Finally a generic framework based on a HTML-JavaScript library is proposed, which could be employed for implementing wide range of software solutions from e-learning to cloud-based modeling environments.