title: Adaptive techniques for specification matching in embedded systems: A comparative study

authors: Malik, Robi

subjects: computer science

abstract: The specification matching problem in embedded systems is to determine whether an existing component may be adapted suitably to match the requirements of a new specification. Recently, a refinement called forced simulation has been introduced to formally address this problem. It has been established that when a forced similarity relation exists between a component and its specification, an adapter process can be constructed so that the composition of the adapter and the component fulfil the specification. This looks very similar to synthesis methods in supervisory control theory, where a controller is constructed to make a plant satisfy a desired specification. However, due to the need for state-based hiding in specification matching, supervisory control theory is not directly applicable. This paper develops a supervisory control based solution to the specification matching problem by modifying the problem representation. Subsequently, a comparison of the forced simulation and supervisory control based specification matching methods is made.

text: Adaptive techniques for specification matching in embedded systems: A comparative study The specification matching problem in embedded systems is to determine whether an existing component may be adapted suitably to match the requirements of a new specification. Recently, a refinement called forced simulation has been introduced to formally address this problem. It has been established that when a forced similarity relation exists between a component and its specification, an adapter process can be constructed so that the composition of the adapter and the component fulfil the specification. This looks very similar to synthesis methods in supervisory control theory, where a controller is constructed to make a plant satisfy a desired specification. However, due to the need for state-based hiding in specification matching, supervisory control theory is not directly applicable. This paper develops a supervisory control based solution to the specification matching problem by modifying the problem representation. Subsequently, a comparison of the forced simulation and supervisory control based specification matching methods is made.

year: 2005

title: Semi-random model tree ensembles: An effective and scalable regression method

authors: Pfahringer, Bernhard

subjects: computer science

abstract: We present and investigate ensembles of semi-random model trees as a novel regression method. Such ensembles combine the scalability of tree-based methods with predictive performance rivalling the state of the art in numeric prediction. An empirical investigation shows that Semi-Random Model Trees produce predictive performance which is competitive with state-of-the-art methods like Gaussian Processes Regression or Additive Groves of Regression Trees. The training and optimization of Random Model Trees scales better than Gaussian Processes Regression to larger datasets, and enjoys a constant advantage over Additive Groves of the order of one to two orders of magnitude.

text: Semi-random model tree ensembles: An effective and scalable regression method We present and investigate ensembles of semi-random model trees as a novel regression method. Such ensembles combine the scalability of tree-based methods with predictive performance rivalling the state of the art in numeric prediction. An empirical investigation shows that Semi-Random Model Trees produce predictive performance which is competitive with state-of-the-art methods like Gaussian Processes Regression or Additive Groves of Regression Trees. The training and optimization of Random Model Trees scales better than Gaussian Processes Regression to larger datasets, and enjoys a constant advantage over Additive Groves of the order of one to two orders of magnitude.

year: 2011

title: Dating of recent low sea level and Maori rock carvings Ongari Point

authors: Schofield, J.C.

subjects: carving

abstract: A sea level of at least 1.5ft below the present one, and contemporaneous rock carvings have a radiocarbon date of 180±50 years B.P.

text: Dating of recent low sea level and Maori rock carvings Ongari Point A sea level of at least 1.5ft below the present one, and contemporaneous rock carvings have a radiocarbon date of 180±50 years B.P.

year: 1968