title: Synthesis observation equivalence and weak synthesis observation equivalence

authors: Mohajerani, Sahar

subjects: computer science

abstract: This working paper proposes an algorithm to simplify automata in such a way that compositional synthesis results are preserved in every possible context. It relaxes some requirements of synthesis observation equivalence from previous work, so that better abstractions can be obtained. The paper describes the algorithm, adapted from known bisimulation equivalence algorithms, for the improved abstraction method. The algorithm has been implemented in the DES software tool Supremica and has been used to compute modular supervisors for several large benchmark examples. It successfully computes modular supervisors for systems with more than 10¹² reachable states.

text: Synthesis observation equivalence and weak synthesis observation equivalence This working paper proposes an algorithm to simplify automata in such a way that compositional synthesis results are preserved in every possible context. It relaxes some requirements of synthesis observation equivalence from previous work, so that better abstractions can be obtained. The paper describes the algorithm, adapted from known bisimulation equivalence algorithms, for the improved abstraction method. The algorithm has been implemented in the DES software tool Supremica and has been used to compute modular supervisors for several large benchmark examples. It successfully computes modular supervisors for systems with more than 10¹² reachable states.

year: 2012-07-30

title: Salinity indicators in sediment through the fluvial-to-marine transition (Fraser River, Canada).

authors: Dashtgard, Shahin E.

subjects: Canada

abstract: Many sediment attributes have been proposed as proxies for determining salinity conditions under which sediment is deposited, and six attributes (Sr/Ba-HAc, Sr/Ba-NH4Ac, δ13Corg, C/N, and the relative abundances and concentrations of dinoflagellate cysts) are compared here. In this paper, sediment attributes from the Fraser River Delta, Canada and surrounding coastal areas are compared by depositional position along the fluvial-to-marine transition, by salinity, and by sedimentological characteristics. Along the fluvial-to-marine transition, most attributes exhibit distinct trends between parts of the river that experience sustained marine water (saltwater) influence over seasonal and tidal timeframes, and parts that experience only freshwater or periodic saltwater influence. No attributes are reliable indicators of depositional position where saltwater incursion is short lived or where water is fresh. Where marine influence is sustained, Sr/Ba-HAc and Sr/Ba-NH4Ac are the most reliable positional indicators along the fluvial-to-marine transition. When compared strictly to salinity, Sr/Ba-HAc, Sr/Ba-NH4Ac, and δ13Corg all correlate predictably except in delta front and prodelta settings. Our data show that all six sediment attributes are heavily impacted by river-derived sedimentation, and it is not appropriate to compare values from strongly river-influenced settings (e.g., deltas) with those from weakly river-influenced settings (e.g., bays and estuaries).

text: Salinity indicators in sediment through the fluvial-to-marine transition (Fraser River, Canada). Many sediment attributes have been proposed as proxies for determining salinity conditions under which sediment is deposited, and six attributes (Sr/Ba-HAc, Sr/Ba-NH4Ac, δ13Corg, C/N, and the relative abundances and concentrations of dinoflagellate cysts) are compared here. In this paper, sediment attributes from the Fraser River Delta, Canada and surrounding coastal areas are compared by depositional position along the fluvial-to-marine transition, by salinity, and by sedimentological characteristics. Along the fluvial-to-marine transition, most attributes exhibit distinct trends between parts of the river that experience sustained marine water (saltwater) influence over seasonal and tidal timeframes, and parts that experience only freshwater or periodic saltwater influence. No attributes are reliable indicators of depositional position where saltwater incursion is short lived or where water is fresh. Where marine influence is sustained, Sr/Ba-HAc and Sr/Ba-NH4Ac are the most reliable positional indicators along the fluvial-to-marine transition. When compared strictly to salinity, Sr/Ba-HAc, Sr/Ba-NH4Ac, and δ13Corg all correlate predictably except in delta front and prodelta settings. Our data show that all six sediment attributes are heavily impacted by river-derived sedimentation, and it is not appropriate to compare values from strongly river-influenced settings (e.g., deltas) with those from weakly river-influenced settings (e.g., bays and estuaries).

year: 2022

title: On the stage Māori medium ITE: Listening to students’ voices

authors: Lee-Morgan, Jenny Bol Jun

subjects: Māori medium education

abstract: Māori-medium initial teacher education (ITE) is a small but highly important group ‘on stage’ in te ao Māori and New Zealand education. While education plays a major role in Māori language revitalisation, Māori language is also pivotal to Māori education if the aspiration ‘to live as Māori’ (Durie, 2001) is to be fulfilled. Māori-medium teachers are critical to the success of learners and their whānau who select a Māori-medium pathway and who can make a meaningful difference to the educational outcomes of Māori (Hōhepa, Hāwea, Tamatea, & Heaton, 2014). This article draws on the students’ voices in a two-year research project that centered on the development of a teaching and learning initiative within one Māori-medium ITE programme. Building on previous work by Hōhepa et al. (2014), this study adds another layer of students’ voices to understand more clearly language related issues and student experiences in Māori-medium ITE programmes. The article presents some of the complexities associated with Māori language regeneration facing students of Māori-medium ITE, with the understanding that whatever appears on the stage is always part of a greater narrative behind the scenes.

text: On the stage Māori medium ITE: Listening to students’ voices Māori-medium initial teacher education (ITE) is a small but highly important group ‘on stage’ in te ao Māori and New Zealand education. While education plays a major role in Māori language revitalisation, Māori language is also pivotal to Māori education if the aspiration ‘to live as Māori’ (Durie, 2001) is to be fulfilled. Māori-medium teachers are critical to the success of learners and their whānau who select a Māori-medium pathway and who can make a meaningful difference to the educational outcomes of Māori (Hōhepa, Hāwea, Tamatea, & Heaton, 2014). This article draws on the students’ voices in a two-year research project that centered on the development of a teaching and learning initiative within one Māori-medium ITE programme. Building on previous work by Hōhepa et al. (2014), this study adds another layer of students’ voices to understand more clearly language related issues and student experiences in Māori-medium ITE programmes. The article presents some of the complexities associated with Māori language regeneration facing students of Māori-medium ITE, with the understanding that whatever appears on the stage is always part of a greater narrative behind the scenes.

year: 2017