Extending classical planning with state constraints: Heuristics and search for optimal planning

We present a principled way of extending a classical AI planning formalism with systems of state constraints, which relate - sometimes determine - the values of variables in each state traversed by the plan. This extension occupies an attractive middle ground between expressivity and complexity. It enables modelling a new range of problems, as well as formulating more efficient models of classical planning problems. An example of the former is planning-based control of networked physical systems - power networks, for example - in which a local, discrete control action can have global effects on continuous quantities, such as altering flows across the entire network. At the same time, our extension remains decidable as long as the satisfiability of sets of state constraints is decidable, including in the presence of numeric state variables, and we demonstrate that effective techniques for cost-optimal planning known in the classical setting - in particular, relaxation-based admissible heuristics - can be adapted to the extended formalism. In this paper, we apply our approach to constraints in the form of linear or non-linear equations over numeric state variables, but the approach is independent of the type of state constraints, as long as there exists a procedure that decides their consistency. The planner and the constraint solver interact through a well-defined, narrow interface, in which the solver requires no specialisation to the planning contextThis work was supported by ARC project DP140104219, “Robust AI Planning for Hybrid Systems”, and in part by ARO grant W911NF1210471 and ONR grant N000141210430

LinGraph: a graph-based automated planner for concurrent task planning based on linear logic

In this paper, we introduce an automated planner for deterministic, concurrent domains, formulated as a graph-based theorem prover for a propositional fragment of intuitionistic linear logic, relying on the previously established connection between intuitionistic linear logic and planning problems. The new graph-based theorem prover we introduce improves planning performance by reducing proof permutations that are irrelevant to planning problems particularly in the presence of large numbers of objects and agents with identical properties (e.g. robots within a swarm, or parts in a large factory). We first present our graph-based automated planner, the Linear Logic Graph Planner (LinGraph). Subsequently we illustrate its application for planning within a concurrent manufacturing domain and provide comparisons with four existing automated planners, BlackBox, Symba-2, Metis and the Temporal Fast Downward (TFD), covering a wide range of state-of-the-art automated planning techniques and implementations. We show that even though LinGraph does not rely on any heuristics, it still outperforms these systems for concurrent domains with large numbers of identical objects and agents. These gains persist even when existing methods on symmetry reduction and numerical fluents are used, with LinGraph capable of handling problems with thousands of objects. Following these results, we also show that plan construction with LinGraph is equivalent to multiset rewriting systems, formally relating LinGraph to intuitionistic linear logic. © 2017, Springer Science+Business Media New York

Knowledge in the making: methodological considerations on the production, dissemination, and usage of "small forms in education"

Collecting and producing mass data has offered an appealing way to condense educational phenomena. However, thus far, little attention has been given to the seemingly insignificant preprinted forms that represent the basis for compiling and aggregating data. Taking inspiration from science and technology studies and the ensuing development of so-called paper technologies, this article highlights the potential of small forms in education that were used to record, evaluate, and aggregate data for educational statistics. By suggesting a multi-level methodological approach that we frame as 3D hermeneutics, we seek to contribute a methodological proposal on how to analyse these materials and showcase what lies beneath – or what comes before – the knowledge produced by educational statistics. These analyses draw on pre-printed forms collected by the Prussian educational administration at the turn of the nineteenth century, and re-trace the contexts they were embedded in, examine their materiality, and reconstruct their usage

Visual syntax and intelligence

This thesis project is concerned with the role that graphic designers have in making learning materials more effective. It is focused on the need for instructional materials to reflect current advances in cognitive psychology and our society\u27s definition of intelligence. Most instructional materials today are outdated and ineffective. Some reasons are political, others are socio-economic, and some fall within the scope of the designed environment. Learning materials, especially textbooks, designed before the 1980\u27s have been designed without standards, and at a time when intelligence was seen as a narrow list of abilities

Theoretical Foundations for Structural Symmetries of Lifted PDDL Tasks

We transfer the notion of structural symmetries to lifted planning task representations, based on abstract structures which we define to model planning tasks. We show that symmetries are preserved by common grounding methods and we shed some light on the relation to previous symmetry concepts used in planning. Using a suitable graph representation of lifted tasks, our experimental analysis of common planning benchmarks reveals that symmetries occur in the lifted representation of many domains. Our work establishes the theoretical ground for exploiting symmetries beyond their previous scope, such as for faster grounding and mutex generation, as well as for state space transformations and reduction

Testing End-To-End Chains using Domain Specific Languages

Testing systems is a time consuming (and hence expensive) activity. Nevertheless, it is a very important and necessary step before using systems, especially safety critical systems. Therefore, many different test procedures are used: Unit Tests, Black-Box Tests, Software Integration Tests (SWI), Hardware-Software Integration Tests (HSI), Hardware-In-The-Loop Tests, just to name a few. Especially in the avionics domain, a variety of systems and applications communicate which each other. Furthermore, they depend and rely on the received information. However, some faults are only detected when all systems are connected and in operational mode. A new testing approach is to create model based End-To-End Chain scenarios with original and simulated equipment in any combination. The first aim is to automatically derive test data and test cases from the model, which is defined by a Domain Specific Language (DSL). Test data generators can be attached to quickly create a variety of stimuli for the systems under test. Furthermore, the system under test can be stimulated by either original equipment â which is connected to the test bench â or the test bench can simulate equipment and create inputs for the tested systems. Any mixture of simulated and original equipment is possible and can be changed on the fly. In the end, the results from the system under test are collected. These results can then be displayed back in the model. This method was used and improved in the project â E-Enabled Cabin (E-Cab)â in which the author was involved. Passengers traveling by plane are in the focus of this project. Complete services and service chains â ranging from booking at home with a computer, being en route using mobile devices to leaving the destination airport â are created and used by many systems communicating with each other. A special focus is set on a guidance scenario at an airport. The user of the system signs in to a guidance and notification system which will inform him via his own digital equipment (mobile device/smart phone). The system notifies the user about his in-time status. Either he is in-time for his flight, or he needs to hurry up and proceed to the next area or he will be too late and cannot catch his flight. The DSL itself is designed according to the comprehension of information processes. The ability of the human brain to process visual information in parallel â in contrast to sequential processing of textual information â is described and applied in the design of the DSL and the concepts of the project. The development of the DSL and the workflow is developed with the â real worldâ in mind. This means that the work fits in established workflows and enhances the current situation. As this project took place in the aircraft industry, the appropriate development standards, like DO178B and ABD100/200 (Airbus Directives ABD100/ABD200), build the foundation. The generation of clean code is established by applying generator guidelines (through coding standards) in order to create maintainable tests and test data

Santa Fe Traffic Operation Center

The New Mexico Department of Transportation is expanding the District 5 Traffic Operations Center (TOC). We assessed the current communication methods and technologies used within the District 5 TOC. From various interviews and research we recommended that the TOC increase operational efficiency and interagency communications by implementing the following technologies and systems: Dashboard systems, NMRoads access expansion, automatic vehicle location, jurisdictional boundaries and infrastructure map, and interagency conferences, notification systems and contact lists

TECHNICAL REPORT WRITING

This is a brief manual intended primarily to instruct junior engineering personnel working on civil works for the Corps of Engineers in the proper procedures for preparing reports. Some of the contents were papers delivered at a conference on the use of English in Corps of Engineers reports. The manual is complicated by the Corps of Engineer’s roles as a military organization and as an organization managing civil public works projects and public facilities and by the special problem of having to answer inquiries of members of Congress. Shortly before this guide was issued, the Engineer School had issued a guide on writing military technical reports: Guide to the Preparation of Military Reports of a Technical Nature, 1954