View All Pages

Project

Project

A project is required for this course. A project will typically have an experimental component (software and/or models) backed by a paper describing the principles being investigated.

Due Dates

  • February 20: One page project proposal.
  • March 20: One page project status report due.
  • April 17: One page project status report due.
  • May 5: Project paper submission due.
  • May 12: Review of project papers due.
  • May 14: Project presentations.
  • May 16: Project papers due.

Guidelines

The paper component will be expected to be conference quality, with appropriately chosen and cited references to the literature. Papers must be scholarly, meaning that they describe original work, critically assess both the advantages and disadvantages of that work, credit external contributions to that work, and compare to other published work. Ideas in the paper should be backed by concrete examples in the form of models and/or software implementations.

Papers should be no more than four pages in length, two column format, as given by the Latex template. Students are required to submit an extended abstract for review by other students in the class. The extended abstract should follow the same format as the paper, but can be shorter. A final presentation will be required.

Project Suggestions

Below is an evolving list of project suggestions:

  1. Protocol Modeling. There is a great deal of interest these days in the effects that communication networks have on the dynamics of cyber-physical systems. The goal of this project will be to evaluate modeling techniques for modern and evolving protocols, such as OpenWSN Links to an external site. (see Download Watteyne et al. 2012), CoAP Links to an external site., XMPP Links to an external site., MQTT, Links to an external site. and/or Alljoyn Links to an external site.. One approach would be to evaluate simulation modeling choices, such as DE combined with state machines. For example, a focus of current interest would assess the ability to leverage multiform time toward modeling the effects of clock synchronization in OpenWSN on energy consumption and network dynamics. Also of interest is location-aware services and service discovery.
  2. BigActors. The Download BigActors model of computation leverages Milner's Download Bigraphs, where two superimposed graphs represent locality and connectivity. This is related to the Download Diposet structure introduced by Davis, which superimposes partially ordered sets representing hierarchy and connectivity. There are a number of possible projects that would build on these models, either exploring their theory, or analyzing their utility in practical design of location-aware distributed systems and services.
  3. Shared Data Structures. Asynchronous deterministic concurrent models of computation such as process networks and dataflow have difficulty with shared data structures. Naive implementations trigger a great deal of copying of data. Optimizations such as reference counts, and more interesting, the recently emerged Download differential dataflow techniques, promise to be much better. Differential dataflow encodes related versions of a data structure by encoding their differences rather than making copies. This project will build models of such encodings, formulate optimization problems, provide implementation strategies, and perform experiments to assess the strategies. The UpdatedArrayToken class in Ptolemy II has a very rudimentary start on such an effort.
  4. Discrete-Event Variants. A number of variants of discrete-event semantics have appeared over time. The recently introduced Download P language, for example, has been used effectively to synthesize device drivers. Simulink has recently been extended with SimEvents. The much older DEVS [Zeigler et al., Theory of Modeling and Simulation, Academic Press, 2000] is widely use in large scale simulation. Network simulators such as NS-3 and Opnet also use a DE variant. Hardware description languages VHDL, Verilog, and System-C all use DE variants. This project will study these variants, compare them using concrete models implemented using real tools, and analyze them according to the semantic principles discussed in the course.
  5. Distributed Timed Systems. A number of programming model have been developed for realizing distributed real-time systems. Recent developments include physically-asynchronous, logically synchronous ( Download PALS) designs and Download Ptides. These appear to be related to the older concept of Download latency-insensitive design and many prior efforts to desynchronize implementations of synchronous languages. The purpose of this project is to compare these approaches by seeking concrete examples that illustrate the strengths and weaknesses of each, and to analyze them according to the semantic principles of the course.
  6. Actor Languages. The low-level Java programming currently used to create actors in Ptolemy II is far from satisfactory. Earlier efforts to create domain-specific languages (DSLs) for developing actors, such as Download Cal, are promising, but have not caught on. Modern languages such as Download Scala that embed DSLs within Java seem promising. The purpose of this project is to explore how actors should be best designed. The project should examine prior actor languages, including at least Download StreamIT and Download Cal.
  7. Modal Models. A number of techniques for constructing modal models have been developed, including Statecharts, Hybrid Bond graphs, Simulink/Stateflow, Ptolemy II, and others. There are also some specification styles that focus on parameterizing models and switching parameter values according to mode changes, including Download Scenarios and Download SPDF. The purpose of this project is to study and analyze these alternatives through concrete examples of models with mode changes.
  8. Threads. Threads are well understood to be problematic as a concurrent programming model. A number of more disciplined and patterned uses of threads have been proposed, including Download Protothreads, Download Cilk, and Download Behavioral Programming. The purpose of this project is to analyze these techniques for determinism and expressiveness in light of the analysis techniques given in this course.
  9. Concurrent user interfaces: Concurrency models for user interface design have been a mixed bags. Attempts to use threads, as in Java, have failed miserably. Prevailing methods are event based, but rather ad-hoc and unprincipled. An old but recently enhanced event-based model of computation called Event Relationship Graphs (ERG) seems to hold considerable promised to improve the situation. This project would explore this idea through prototypes and analysis.
  10. Actor-oriented security models: Study the problem of security in distributed actor-oriented models and implement a security toolkit for building secure distributed models. This project would build on concepts like capabilities and leverage the fact that actor libraries can be more flexibly designed than programming languages. Recently emerging ideas like Download opacity (for preserving privacy) could also be relevant.
  11. Textual syntaxes for block diagrams: Visual syntaxes for actor-oriented models have a certain appeal for pedagogy, but many people feel that visual syntaxes will never scale sufficiently to be able to deal with complex designs. This project will explore textual syntaxes that are compact, readable, and capable of expressing (at least) the Ptolemy II abstract syntax for actor-oriented models.
  12. Static analysis of continuous-time models: The theory of control systems has a rich set of formal analysis techniques for continuous-time feedback systems. This project will develop analysis tools that apply that theory to Ptolemy II models in the Continuous domain to perform, for example, stability or robustness analyses. A key element will be to handle modal models.
  13. Dataflow with time stamps: Dataflow models may benefit from using time stamps. A starting point for researching this is to look at Download Naiad.