title: Compositional synthesis of supervisors in the form of state machines and state maps

authors: Mohajerani, Sahar

subjects: computer science

abstract: This paper investigates the compositional abstraction-based synthesis of least restrictive, controllable, and nonblocking supervisors for discrete event systems that are given as a large number of finite-state machines. It compares a previous algorithm that synthesises modular supervisors in the form of state machines, with an alternative that records state maps after each abstraction step and uses these to control the system. The state map-based algorithm supports all abstraction methods used previously, and in addition allows for nondeterminism, hiding, and transition removal. It has been implemented in the software tool Supremica and applied to several large industrial models. The experimental results and the complexity analysis show that state maps can be computed efficiently and in many cases require less memory than state machine-based supervisors.

text: Compositional synthesis of supervisors in the form of state machines and state maps This paper investigates the compositional abstraction-based synthesis of least restrictive, controllable, and nonblocking supervisors for discrete event systems that are given as a large number of finite-state machines. It compares a previous algorithm that synthesises modular supervisors in the form of state machines, with an alternative that records state maps after each abstraction step and uses these to control the system. The state map-based algorithm supports all abstraction methods used previously, and in addition allows for nondeterminism, hiding, and transition removal. It has been implemented in the software tool Supremica and applied to several large industrial models. The experimental results and the complexity analysis show that state maps can be computed efficiently and in many cases require less memory than state machine-based supervisors.

year: 2017

title: Event notification services: analysis and transformation of profile definition languages

authors: Jung, Doris

subjects: computer science

abstract: The integration of event information from diverse event notification sources is, as with meta-searching over heterogeneous search engines, a challenging task. Due to the complexity of profile definition languages, known solutions for heterogeneous searching cannot be applied for event notification.
In this technical report, we propose transformation rules for profile rewriting. We transform each profile defined at a meta-service into a profile expressed in the language of each event notification source. Due to unavoidable asymmetry in the semantics of different languages, some superfluous information may be delivered to the meta-service. These notifications are then post-processed to reduce the number of spurious messages. We present a survey and classification of profile definition languages for event notification, which serves as basis for the transformation rules. The proposed rules are implemented in a prototype transformation module for a Meta-Service for event notification.

text: Event notification services: analysis and transformation of profile definition languages The integration of event information from diverse event notification sources is, as with meta-searching over heterogeneous search engines, a challenging task. Due to the complexity of profile definition languages, known solutions for heterogeneous searching cannot be applied for event notification.
In this technical report, we propose transformation rules for profile rewriting. We transform each profile defined at a meta-service into a profile expressed in the language of each event notification source. Due to unavoidable asymmetry in the semantics of different languages, some superfluous information may be delivered to the meta-service. These notifications are then post-processed to reduce the number of spurious messages. We present a survey and classification of profile definition languages for event notification, which serves as basis for the transformation rules. The proposed rules are implemented in a prototype transformation module for a Meta-Service for event notification.

year: 2004-01-01

title: Whangai: remembering, understanding and experiencing

authors: McRae, Karyn Okeroa

subjects: adoption

abstract: The Māori customary practice of whangai is often equated with adoption or foster care.
There are, however, significant differences between the institutions. Adoption or foster care, tends to be mainly focused on the interests of the child. The institution of whangai, while being cognizant of the interests of the child, is weighted more towards establishing, nurturing and cementing relationships between individuals, families and broader relational networks. In this paper we draw on the lived experiences of six people who have been raised as whangai and/or have raised whangai. We were interested in their understanding of the cultural concept of whangai, how the customary practice of whangai has changed over time, and their projected thoughts on future generations’ experience of whangai. Findings suggest that the institution of whangai remains as a strong vehicle for both the care of children and for the nurturing of whangai kinship relationships. While participants recognised that contemporary Māori social environments have contributed toward multiple manifestations of whangai, most felt it to be an institution that will be valued and carried into the future.

text: Whangai: remembering, understanding and experiencing The Māori customary practice of whangai is often equated with adoption or foster care.
There are, however, significant differences between the institutions. Adoption or foster care, tends to be mainly focused on the interests of the child. The institution of whangai, while being cognizant of the interests of the child, is weighted more towards establishing, nurturing and cementing relationships between individuals, families and broader relational networks. In this paper we draw on the lived experiences of six people who have been raised as whangai and/or have raised whangai. We were interested in their understanding of the cultural concept of whangai, how the customary practice of whangai has changed over time, and their projected thoughts on future generations’ experience of whangai. Findings suggest that the institution of whangai remains as a strong vehicle for both the care of children and for the nurturing of whangai kinship relationships. While participants recognised that contemporary Māori social environments have contributed toward multiple manifestations of whangai, most felt it to be an institution that will be valued and carried into the future.

year: 2006