The International planning competition series and empirical evaluation of AI planning systems

In this paper we consider the role of the International Planning Competition series in the evaluation of planners, both directly through the events themselves, and indirectly through the creation of resources and infrastructure. We also consider the problem of evaluation based on data collected both in the competitions and otherwise and examine some of the issues that arise in attempting to formulate and test hypotheses around the data

Opportunistic Branched Plans to Maximise Utility in the Presence of Resource Uncertainty

Abstract. In many applications, especially autonomous explo-ration, there is a trade-off between operational safety, forcing conser-vatism about resource usage; and maximising utility, requiring high resource utilisation. In this paper we consider a method of generat-ing plans that maintain this conservatism whilst allowing exploitation of situations where resource usage is better than pessimistically es-timated. We consider planning problems with soft goals, each with a violation cost. The challenge is to maximise utility (minimise the violation cost paid) whilst maintaining confidence that the plan will execute within the specified limits. We first show how forward search planning can be extended to generate such plans. Then we extend this to build branched plans: tree structures labelled with conditions on executing branches. Lower cost branches can be followed if their conditions are met. We demonstrate that the use of such plans can dramatically increase utility whilst still obeying strict safety con-straints.

On-board timeline validation and repair : a feasibility study

We report on the progress and outcome of a recent ESAfunded project (MMOPS) designed to explore the feasibility of on-board reasoning about payload timelines. The project sought to examine the role of on-board timeline reasoning and the operational context into which it would fit. We framed a specification for an on-board service that fits with existing practices and represents a plausible advance within sensible constraints on the progress of operations planning. We have implemented a prototype to demonstrate the feasibility of such a system and have used it to show how science gathering operations might be improved by its deployment

GENERATING PLANS IN CONCURRENT, PROBABILISTIC, OVER-SUBSCRIBED DOMAINS

Planning in realistic domains typically involves reasoning under uncertainty, operating under time and resource constraints, and finding the optimal subset of goals to work on. Creating optimal plans that consider all of these features is a computationally complex, challenging problem. This dissertation develops an AO* search based planner named CPOAO* (Concurrent, Probabilistic, Over-subscription AO*) which incorporates durative actions, time and resource constraints, concurrent execution, over-subscribed goals, and probabilistic actions. To handle concurrent actions, action combinations rather than individual actions are taken as plan steps. Plan optimization is explored by adding two novel aspects to plans. First, parallel steps that serve the same goal are used to increase the plan’s probability of success. Traditionally, only parallel steps that serve different goals are used to reduce plan execution time. Second, actions that are executing but are no longer useful can be terminated to save resources and time. Conventional planners assume that all actions that were started will be carried out to completion. To reduce the size of the search space, several domain independent heuristic functions and pruning techniques were developed. The key ideas are to exploit dominance relations for candidate action sets and to develop relaxed planning graphs to estimate the expected rewards of states. This thesis contributes (1) an AO* based planner to generate parallel plans, (2) domain independent heuristics to increase planner efficiency, and (3) the ability to execute redundant actions and to terminate useless actions to increase plan efficiency

Free of charge: an impossible principle in the digital world?

UK higher education has taken a number of bold steps to deliver network services through national planning. However, underlying these pragmatically organised services is a philosophical approach to information provision. Central to that philosophy is that services should be free at the point of use and that we have a duty to the nation to turn out graduates who are not only eager to use electronic services, but have been taught the skills to take the fullest advantage of this. Small nations such as the United Kingdom or the countries of Scandinavia have a huge advantage over the United States. We can practise systematic national planning and introduce services, training and documentation on a countrywide basis. To experiment with and change the whole system is not an opportunity offered to very large decentralised or federal countries

Special Libraries, September 1976

Volume 67, Issue 9https://scholarworks.sjsu.edu/sla_sl_1976/1007/thumbnail.jp

Business operations survey: 2013

Businesses in New Zealand are finding it easier to fill vacancies in 2013, according to this survey of information from businesses with six or more employees. Key facts In 2013: 31 percent of businesses had hard-to-fill vacancies in 2013, compared with 47 percent in 2008. 89 percent of businesses trained staff, with most businesses training staff in health and safety skills. 46 percent of businesses innovated (implemented or developed new or significantly improved goods, services, or methods). Spending on research and development (R&D) rose 7 percent, and now makes up 56 percent of total product development and related activities expenditure