State-based Systems Research Articles

“Keep definition, change category” — A practical approach to state-based system calculi

Faced with the need to quantify software (un)reliability in the presence of faults, the semantics of state-based systems is urged to evolve towards quantified (e.g. probabilistic) nondeterminism. When one is approaching such semantics from a categorical perspective, this inevitably calls for some technical elaboration, in a monadic setting.This paper proposes that such an evolution be undertaken without sacrificing the simplicity of the original (qualitative) definitions, by keeping quantification implicit rather than explicit. The approach is a monad lifting strategy whereby, under some conditions, definitions can be preserved provided the semantics moves to another category.The technique is illustrated by showing how to introduce probabilism in an existing software component calculus, by moving to a suitable category of matrices and using linear algebra in the reasoning.The paper also addresses the problem of preserving monadic strength in the move from original to target (Kleisli) categories, a topic which bears relationship to recent studies in categorial physics.

Killing epsilons with a dagger: A coalgebraic study of systems with algebraic label structure

We propose an abstract framework for modelling state-based systems with internal behaviour as e.g. given by silent or ϵ-transitions. Our approach employs monads with a parametrized fixpoint operator † to give a semantics to those systems and implement a sound procedure of abstraction of the internal transitions, whose labels are seen as the unit of a free monoid. More broadly, our approach extends the standard coalgebraic framework for state-based systems by taking into account the algebraic structure of the labels of their transitions. This allows to consider a wide range of other examples, including Mazurkiewicz traces for concurrent systems and non-deterministic transducers.

Challenges in Establishing Adolescent Forensic Mental Health Services Within Australian Youth Detention Centres

Young people in custody rank amongst the most marginalized in Australia, and have high rates of mental health disorders. However, the knowledge base to support the emerging field of adolescent forensic psychiatry is limited. Following an appraisal of Australia's state-based youth justice systems, it is proposed that three key challenges need to be addressed: the challenge of advocating for change, the challenge of building an evidence base, and the challenge of developing integrated transitional models of service delivery. Adolescent forensic mental health services that view their role as existing solely within the walls of youth detention centres or community juvenile justice services have too narrow a vision. While not seeking to trivialize their patients’ criminal behaviour, psychiatrists need to drive the delivery of innovative mental health services within youth detention centres and collaborate with those in the political, legal, youth justice, education and child safety sectors to inform debate of the challenges faced by young people in custody.

Providing Optimal Stroke Care through Regional, Local, and In hospital Collaborations

From the beginning of the pivotal NINDS rtPA Stroke Study in January of 1991, the past 2 decades has witnessed an incredible paradigm change in the perception and management of acute ischemic stroke. From a disease previously associated with nihilism and fatalism to one of empowerment, from both a patient and healthcare provider, stroke care in 2013 represents a revolutionary change. The early years of this revolution in care centered around new therapies and better overall acute stroke management. Later, armed with IV rt-PA and intra-arterial approaches, stroke care improved not based on new interventions but through better integration and organization of stroke resources. The coming decade will continue to see stroke care improve, largely based on these stroke systems of care. Organization of stroke care begins in the hospital, centered on the stroke team, but to truly utilize regional stroke resources, stroke systems of care must be organized within discrete regions of care to optimally educate, identify, triage, and manage all potential stroke patients. National standards for defining stroke center capabilities began in 2000. Further accreditation efforts, largely by the Joint Commission, began in 2005 and now serve as discrete measurements for stroke capabilities. Mirroring trauma system models, national organizations, such as the American Heart Association, have established best practices for acute stroke care, and defined the various capabilities of stroke hospitals at each level of capacity. Adding contemporary guidelines, again largely developed by the AHA, these guiding principles and best practices are used within regions to define best stroke practice. The 50,000 ft view of stroke systems of care focuses on the state-based systems. Within the U.S. state-based stroke systems of care provide the largest scale of stroke organization, in part because of state-based prehospital EMS organization. Even at the state level, a one size fits all approach is too broad to be effectively implemented across the various practice settings within a state. It is more effective to take national best practice and guidelines and work with state committees consisting of all the major stakeholders within a state and often lead in part by the state department of health, to translate best practice into regionally appropriate systems of care. Incorporating prehospital care into these regional plans is critical to ensure appropriate triage based on regional hospital stroke capabilities. Using nationally identified best practice with state-based guidance and organization stroke systems of care are implement within a distinct geographic region. These regions are based in part by the capabilities within a geographic region (or lack there of), and the organization and availability of prehospital care services, both Emergency Medical Services, 911 dispatch centers, and air medical services. For the complete spectrum of stroke care, rehabilitation facilities must also be considered but are typically not included in the acute phase of stroke system planning. Healthcare and patient stakeholders in these distinct regions need to meet and organize the most locally appropriate stroke system of care, and in particular, develop prehospital triage protocols of stroke patients to the most appropriate stroke hospital. Distance to various hospitals, hospital capabilities, patient preferences, and specific patient characteristics need to be considered in triage protocols but a triage process must also be simple enough to be implemented consistently in a 24/7/365 fashion to avoid prehospital confusion. Hospital-based stroke systems of care have been developed over the past several decades and with newer models of in-hospital organization built around process engineering have shown distinct improvements in time metrics and numbers of patients treated with IV rtPA. Like regional systems of care, a major driving force of internal organization is minimizing times to reperfusion inpatients that may be appropriate for these various therapies. Lastly, the success and impact of hospital, regional, and state-based stroke systems need to be evaluated on a continuing basis. Education, feedback, and refining of stroke systems of care must be in place given the changing face of healthcare and capabilities, demographic changes, and knowledge updates. When all systems work synergistically, patient outcomes can be optimized.

Global, local and glocal schools: the role of comparative law and the impact of globalisation

Australian legal education has evolved from teaching within State-based legal systems to qualify students for legal practice within that system to a national system in which students can qualify for practice across the country. This calls for a law degree that satisfies regulatory requirements settled nationally by judges and other members of the legal profession. The Australian qualification is also recognised and accepted in many overseas jurisdictions. It is important now to internationalise the educational experience of law students to prepare them for new modes of professional legal practice at home and abroad. This covers both content of their work and the skills that are needed for it. In the many debates on this subject, three modes of internationalisation of the curriculum are suggested: segregation; integration; and immersion. The first is to have separate courses or qualifications to recognise this dimension. The second is to make internationalisation an intrinsic part of all teaching. The third is to send the student to another legal system to study and live inside it. The most common problem is that of resources, both human and educational. Few university lawyers are expert in more than one system or have the skills to move from one to another. An internationalised perspective can be adopted in basic domestic subjects such as contract or family law. Secondly, those hybrid areas of international commercial law such as international sales, arbitration and intellectual property, where there is an amalgam of many systems of law, can be used to isolate the core. It is dangerous simply to adopt a comparative law analysis that sees legal systems as separate entities and disregards interconnectedness. What is fatal is glocalisation—the projection of law-at-home merely to capture a foreign market.

From Branching to Linear Time, Coalgebraically

We consider state-based systems modelled as coalgebras whose type incorporates branching, and show that by suitably adapting the definition of coalgebraic bisimulation, one obtains a general and uniform account of the linear-time behaviour of a state in such a coalgebra. By moving away from a boolean universe of truth values, our approach can measure the extent to which a state in a system with branching is able to exhibit a particular linear-time behaviour. This instantiates to measuring the probability of a specific behaviour occurring in a probabilistic system, or measuring the minimal cost of exhibiting a specific behaviour in the case of weighted computations.

Verifying and Comparing Finite State Machines for Systems that Have Distributed Interfaces

This paper concerns state-based systems that interact with their environment at physically distributed interfaces, called ports. When such a system is used a projection of the global trace, a local trace, is observed at each port. As a result the environment has reduced observational power: the set of local traces observed need not define the global trace that occurred. We consider the previously defined implementation relation ⊆s and prove that it is undecidable whether N ⊆s M and so it is also undecidable whether testing can distinguishing two states or FSMs. We also prove that a form of model-checking is undecidable when we have distributed observations and give conditions under which N ⊆s M is decidable. We then consider implementation relation ⊆sk that concerns input sequences of length κ or less. If we place bounds on κ and the number of ports then we can decide N ⊆sk M in polynomial time but otherwise this problem is NP-hard.

Transnational Private Regulatory Governance: Ambiguities of Public Authority and Private Power

I INTRODUCTION The proliferation of norm-making, that is, the creation of legally binding rules outside of the institutional, state-based systems of rule-setting, very forcefully accentuates the dilemma of the modern nation state's exhaustion in an era of globalization. Seen against the background of the law-as-victim thesis, the ubiquitous forms of private both inside and outside of the nation-state, are regularly read as signs of the erosion processes, which allegedly characterize the general fate of the sovereign state in the global era and find a particularly striking illustration in the relativization of the state's authority to administer and to control the institutions of norm-creation. (1) However, a sociological perspective, the current interest of so-called governance theories (2) in falls squarely into the discipline's concern with the study of societal differentiation processes. Such accounts play a crucial role in informing legal scholars' inquiries into the nature and consequences of norm-creation processes for the study of in general. (3) Compressed into a relatively small space then, we can discern some of the central challenges to current legal thinking: under the impression of an unquestionably deep-running transformation of forms of public and ordering, lawyers seek explanations by contextualizing these developments. What they find are impressive accounts of globalization processes, which have prompted a considerable number of social science disciplines to fundamentally rethink their analytical categories and conceptual frameworks. In this context, legal scholars find that their own accounts of the growing limits of regulatory capacity in view of, for example, border-crossing environmental or security concerns, coalesce with observations made by political scientists, sociologists, geographers, or anthropologists regarding a fundamental decentralization and privatization of norm-creation and legal-political decision-making. For law, to be sure, there is much at stake, as this multidisciplinary diagnosis strongly suggests lawyers' need to rethink the proper foundations, boundaries and--in fact--the nature of their object itself. The rich accounts of legal pluralism and non-state-based norm-creation, which are central to current depictions of the shift from government to governance, can be read as strong signals that itself has an identity crisis, a crisis regarding its own nature and function. It is important to note, however, that accounts of a co-existence of legal and non-legal forms of social regulation, while proliferating under the impression of reduced state capacity to effectively regulate transnational issues, have always been part of the central make-up of legal theory. Early anthropological and legal theoretical accounts of the extensive efficacy of informal orders should have alerted lawyers a long time ago to the tension between and non-law, which arguably lies at the heart of any legal system. This article suggests a revisiting of the field of lex mercatoria, the body of norms associated with a transnational law merchant. These norms and their surrounding institutions and processes, although much contested, have forever assumed a prominent place in studies of ordering, driven particularly by the fact that the lex mercatoria reaches far, far back into past centuries of economic globalization, and is thus seen as testifying to both the reality and the viability of transnational beyond the state. (4) In light of the concerns raised by lawyers regarding the limits of and legal norm-creation in the context of globalization, the pressing question concerning the lex mercatoria appears to be that of the possibility of an autonomous legal order, that is, of a functioning legal system, which is itself not grounded in the nation-state's institutionalized norm-creation processes. …

Identifying the Effect of Model Modifications in State-Based Models and Systems

System modeling is a widely used technique to model state-based systems. System models are often used during the development of a software system, e.g., in partial code generation and in test generation. Several modeling languages have been developed to model state-based software systems, e.g., EFSM, SDL, and State Charts. Although state-based modeling is very useful, system models are usually large and complex, and they are frequently modified because of specification changes. Identifying the effect of these changes on the model and consequently on the underlying system is usually challenging and time-consuming. In this paper, we present an approach to automatically identify the effect of modifications made to the model. The goal is to identify those parts of the model that may exhibit different behaviors because of the modification. These are usually critical parts of the system that should be carefully tested. In this approach, the difference between the original model and the modified model is identified, and then the affected parts of the model are computed based on model dependence analysis. An empirical study on different EFSM models is performed in order to identify the affected parts of the model after a modification. The results of the study suggest that our approach could considerably reduce the amount of time and efforts spent to validate the model after a modification.

Inter-governmental land information asymmetries in Australia

Land information has an important role in informing macroeconomic policy. Timely and accurate market information is essential for evidence-based fiscal and monetary decisions. Currently in Australia, there is a gap between the creators of land information at state level and the users at federal level. The capacity of evidence-based policy is under-realised as a result. This paper explores the inter-governmental flow of land market information within three state-based land administration systems in Australia. Results show that integration is occurring within some state land agencies; however, communication with federal government agencies is limited, leading to information asymmetries. Future collaboration is essential. This will require an understanding of and openness to information sharing, involving a move away from historic silo approaches to land information creation and use.

A formal abstract framework for modelling and testing complex software systems

The contribution of this paper is twofold: first, it defines a unified framework for modelling abstract components, as well as a formalization of integration rules to combine their behaviour. This is based on a coalgebraic definition of components, which is a categorical representation allowing the unification of a large family of formalisms for specifying state-based systems. Second, it studies compositional conformance testing i.e. checking whether an implementation made of correct interacting components combined with integration operators conforms to its specification.

A coalgebraic perspective on linear weighted automata

Weighted automata are a generalisation of non-deterministic automata where each transition, in addition to an input letter, has also a quantity expressing the weight (e.g. cost or probability) of its execution. As for non-deterministic automata, their behaviours can be expressed in terms of either (weighted) bisimilarity or (weighted) language equivalence.Coalgebras provide a categorical framework for the uniform study of state-based systems and their behaviours. In this work, we show that coalgebras can suitably model weighted automata in two different ways: coalgebras on Set (the category of sets and functions) characterise weighted bisimilarity, while coalgebras on Vect (the category of vector spaces and linear maps) characterise weighted language equivalence.Relying on the second characterisation, we show three different procedures for computing weighted language equivalence. The first one consists in a generalisation of the usual partition refinement algorithm for ordinary automata. The second one is the backward version of the first one. The third procedure relies on a syntactic representation of rational weighted languages.

Engaging with private sector standards: a case study of GLOBALG.A.P.

There is now a fairly substantial literature on private global business regulation which focuses on the rise of non-governmental and private regulatory systems alongside traditional state-based systems. These private systems cross national borders and impact on international trade which, in the intergovernmental realm, is governed by the rules of the World Trade Organization (WTO). In this article, the authors argue that while in principle private global regulatory trade regimes do not fall under WTO jurisdiction, in practice they are difficult to keep separate. They therefore have the potential to become a concern within the WTO, not only in legal terms, but also from a political perspective because private global regulatory schemes may (re)introduce the distortions into international trade that WTO rules sought to remove. In some cases, a hybridisation of standards occurs as private standards are recognised by public regulatory structures. National governments may find themselves squeezed between their international obligations and the pressures of their citizens, either to respond to consumer concerns themselves and risk being in conflict with their international obligations or to respond to producers seeking action against ‘private red tape’ which is nominally beyond the scope of the WTO. The article takes as its case study an international business-to-business agri-food standards body, GLOBALG.A.P., and explores the issues that arise for global trade governance from the growth in private regulation.

Modular algorithms for heterogeneous modal logics via multi-sorted coalgebra

State-based systems and modal logics for reasoning about them often heterogeneously combine a number of features such as non-determinism and probabilities. In this paper, we show that the combination of features can be reflected algorithmically, and we develop modular decision procedures for heterogeneous modal logics. The modularity is achieved by formalising the underlying state-based systems as multi-sorted coalgebras and associating both a logical and algorithmic description with a number of basic building blocks. Our main result is that logics arising as combinations of these building blocks can be decided in polynomial space provided this is also the case for the components. By instantiating the general framework to concrete cases, we obtain PSpace decision procedures for a wide variety of structurally different logics, describing, for example, Segala systems and games with uncertain information.

Categorifying Computations into Components via Arrows as Profunctors

The notion of arrow by Hughes is an axiomatization of the algebraic structure possessed by structured computations in general. We claim that an arrow also serves as a basic component calculus for composing state-based systems as components—in fact, it is a categorified version of arrow that does so. In this paper, following the second author's previous work with Heunen, Jacobs and Sokolova, we prove that a certain coalgebraic modeling of components—which generalizes Barbosa's—indeed carries such arrow structure. Our coalgebraic modeling of components is parametrized by an arrow A that specifies computational structure exhibited by components; it turns out that it is this arrow structure of A that is lifted and realizes the (categorified) arrow structure on components. The lifting is described using the first author's recent characterization of an arrow as an internal strong monad in Prof, the bicategory of small categories and profunctors.

Defining Equity: Multiple Perspectives to Analyzing the Performance of Diverse Learners

Defining equity within the context of a diverse, multiracial, multiethnic, multilingual, and multicultural society, and one where social class strongly influences one's life chances is problematic. This chapter reexamines equity in an attempt to advance the discourse beyond the debate about strategies to close the achievement gap between White students and students of color. I situated the issue of equity within an analysis of broader social forces that cultivate inequality throughout society in employment, housing, criminal justice, and so forth so that educational inequality is part and parcel of overarching social ills. The notion of equity will be unpacked by asking a more basic and fundamental question about the ultimate purpose of education. If we assume the end game of education is producing student learning, then we should ask whether learning outcomes are distributed randomly across race, ethnicity, and social class. Moreover, I will explore whether No Child Left Behind (NCLB)-like assessments or high-stakes tests measure real learning necessary for social and economic success, or do they measure something else. The role of increased accountability via state-based systems as an approach to obtaining equity is hotly debated. Although advocates are many, several studies have found the consequences of high-stakes testing, which are nonobvious and perhaps unintended, have not helped advance the nation toward equitable schooling. The pursuit of educational equity has long been a goal of reform efforts in the United States. Yet creating a system of education where all children have equal access to quality instruction and widely available opportunities to learn to their fullest human potential has been elusive. More than half a century ago, the Brown v. Board of Education decision settled persistent concerns about the degree to which access to quality schooling was based on race (Ball, 2006; Ball & Samy, 2006; Gutierrez

Spin in CdTe/ZnTe Quantum Dot: Its Potential for Information Storage

Inventions of transistor [1] and integrated circuit [2] established a close link between semiconductor physics and information processing. Rapid development of the field, aptly described by Moore’s law [3], based on optimization of growth and processing techniques as well as on progress in designing complex CPU circuits. Quantum phenomena, inevitable in nanoscale systems, have been considered a limitation to further development of classical electronics according to Moore’s law. Simultaneously, quantum mechanics was recognized as an opportunity to extend the bounds of classical computational paradigm through an idea of quantum computer, described by Deutsch in 1985 [4]. Physical realization of proper building blocks for quantum computer — qubits conform to certain requirements [5] — exhibits major experimental difficulty. Many different approaches were proposed, including trapped ions [6], cavity QED systems [7], liquid state NMR [8], gated quantum dots [9], superconductors [10], crystal lattice impurities [11], and others. Among all these possible solutions, solid-state systems are particularly promising due to relative ease of qubit manipulation, e.g., by electric, optical or magnetic fields. Prospects of future integration of qubits with existing classical electronics also constitute a significant advantage. Drawbacks of the solid state-based systems are related mainly to short coherence times limited by the interaction with the environment. The interaction with the surrounding crystal matrix may be suppressed by e.g. constraining otherwise mobile carriers inside potential well of a quantum dot. This paper presents a selection of our studies of spins in self-assembled CdTe/ZnTe quantum dots from the point of view of quantum information processing. We will discuss three basic processes related to a single quantum dot used as a qubit, that is read-out of encoded information, writing (initialization) the qubit state and evolution of the qubit state which provides means to manipulate it. 2. Samples

Canonical finite state machines for distributed systems

There has been much interest in testing from finite state machines (FSMs) as a result of their suitability for modelling or specifying state-based systems. Where there are multiple ports/interfaces a multi-port FSM is used and in testing, a tester is placed at each port. If the testers cannot communicate with one another directly and there is no global clock then we are testing in the distributed test architecture. It is known that the use of the distributed test architecture can affect the power of testing and recent work has characterised this in terms of local s-equivalence: in the distributed test architecture we can distinguish two FSMs, such as an implementation and a specification, if and only if they are not locally s-equivalent. However, there may be many FSMs that are locally s-equivalent to a given FSM and the nature of these FSMs has not been explored. This paper examines the set of FSMs that are locally s-equivalent to a given FSM M . It shows that there is a unique smallest FSM χ min ( M ) and a unique largest FSM χ max ( M ) that are locally s-equivalent to M . Here smallest and largest refer to the set of traces defined by an FSM and thus to its semantics. We also show that for a given FSM M the set of FSMs that are locally s-equivalent to M defines a bounded lattice. Finally, we define an FSM that, amongst all FSMs locally s-equivalent to M , has fewest states. We thus give three alternative canonical FSMs that are locally s-equivalent to an FSM M : one that defines the smallest set of traces, one that defines the largest set of traces, and one with fewest states. All three provide valuable information and the first two can be produced in time that is polynomial in terms of the number of states of M . We prove that the problem of finding an s-equivalent FSM with fewest states is NP-hard in general but can be solved in polynomial time for the special case where there are two ports.

Using the Chronic Care Model to Address Tobacco in Health Care Delivery Organizations: A Pilot Experience in Washington State

This article describes a Washington State-based Systems Change Pilot Project in which the chronic care model and the model for improvement were used as tools to promote tobacco cessation-related changes within a health care system. Three diverse sites participated in the pilot. Site teams tailored plan-do-study-act tests to site circumstances, addressing current resources and barriers to implementing change. Teams tested system changes that incorporated tobacco use documentation into the routine health services provided. Findings from this pilot suggest that (a) even simple changes with minimal disruption of services can make a difference in improving documentation of tobacco use status; (b) changes to routine practices of health organizations may not be sustainable if ongoing quality assurance mechanisms are not developed; and (c) systems implemented for other disease states within the same organization or patient population are not instinctively applied to tobacco, because of a multitude of factors.

Strategic Use of State and Local Regulatory and Public Health Surveillance Resources to Address the Growing Demand for Food Safety Oversight in the United States

Although considerable progress has been made, federal food safety oversight in the United States has not overcome challenges posed by a decentralized, rapidly expanding food supply network. To complement limitations of federal measures, we believe that state-based food safety regulatory and surveillance systems should be better leveraged and integrated. A strengthened national food safety program would include implementation of uniform standards of food inspection and testing, reciprocal acceptance of state and federal inspection and laboratory findings, and systematic, timely sharing of data on pathogens recovered from contaminated foods and from ill persons.