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The purpose of this paper is to develop new simple logics and translations for hierarchical model checking. Hierarchical model checking is a model-checking paradigm that can appropriately verify systems with hierarchical information and structures.

In this study, logics and translations for hierarchical model checking are developed based on linear-time temporal logic (LTL), computation-tree logic (CTL) and full computation-tree logic (CTL*). A sequential linear-time temporal logic (sLTL), a sequential computation-tree logic (sCTL), and a sequential full computation-tree logic (sCTL*), which can suitably represent hierarchical information and structures, are developed by extending LTL, CTL and CTL*, respectively. Translations from sLTL, sCTL and sCTL* into LTL, CTL and CTL*, respectively, are defined, and theorems for embedding sLTL, sCTL and sCTL* into LTL, CTL and CTL*, respectively, are proved using these translations.

These embedding theorems allow us to reuse the standard LTL-, CTL-, and CTL*-based model-checking algorithms to verify hierarchical systems that are modeled and specified by sLTL, sCTL and sCTL*.

The new logics sLTL, sCTL and sCTL* and their translations are developed, and some illustrative examples of hierarchical model checking are presented based on these logics and translations.

The purpose of this paper is to consider the logical specification, and automated verification, of high‐level robotic behaviours.

The paper uses temporal logic as a formal language for providing abstractions of foraging robot behaviour, and successively extends this to multiple robots, items of food for the robots to collect, and constraints on the real‐time behaviour of robots. For each of these scenarios, proofs of relevant properties are carried out in a fully automated way. In addition to automated deductive proofs in propositional temporal logic, the possibility of having arbitrary numbers of robots involved is considered, thus allowing representations of robot swarms. This leads towards the use of first‐order temporal logics (FOTLs).

The proofs of many properties are achieved using automatic deductive temporal provers for the propositional and FOTLs.

Many details of the problem, such as location of the robots, avoidance, etc. are abstracted away.

Large robot swarms are beyond the current capability of propositional temporal provers. Whilst representing and proving properties of arbitrarily large swarms using FOTLs is feasible, the representation of infinite numbers of pieces of food is outside of the decidable fragment of FOTL targeted, and practically, the provers struggle with even small numbers of pieces of food.

The work described in this paper is novel in that it applies automatic temporal theorem provers to proving properties of robotic behaviour.

An integral part of declarative process modelling is to guarantee that the execution of a declarative workflow is compliant with the respective business rules. The purpose of this paper is to establish a formal framework for representing business rules and determining whether any business rules are violated during the executions of declarative process models.

In the approach, a business rule is phrased in terms of restricted English that is related to a constraint template. Linear temporal logic (LTL) is employed as a formalism for defining the set of constraint templates. By exploiting the theorem-proving feature of the Logics Workbench (LWB), business rule violations are then detected in an automatic manner.

This study explored the viability of encoding: first, process executions by means of LTL and second, business rules in terms of restricted English that built upon pattern-oriented templates and LTL. The LWB was used for carrying out temporal reasoning through automated techniques. The applicability of the formal verification approach was exemplified by a case study concerning supply chain management. The findings showed that practical reasoning could be achieved by combining declarative process modelling, restricted English, pattern-oriented templates, LTL and LWB.

First, new business rule templates are proposed; second, business rules are expressed in restricted English instead of graphical constructs; third, both finite execution trace and business rules are grounded in LTL. There is no need to deal with the semantic differences between different formalisms; and finally, the theorem prover LWB is used for the conformance checking of a finite execution trace against business rules.

Declarative process modelling is a constraint-centric approach that treats business rules as first-class citizens in business process models. Augmenting the declarative process modelling technique with capability to detect the constraint violations during business process execution is of crucial importance. The purpose of this paper is to contribute to the modelling of business rules through a repository of pattern-oriented templates.

The semantics of the business rule templates is underpinned by linear temporal logic (LTL). Automated temporal reasoning is then conducted for determining whether process executions adhere to the business rules through the utilisation of the Logics Workbench (LWB). An application of the methodological framework is illustrated by a realistic case study on degree requirements verification.

To access the practicality of the approach, the case study of this paper is based on the verification of degree requirements, which is different from the domain area of the case study in the author’s prior work. The findings indicated that the temporal framework could be applied to the declarative process modelling in a consistent and efficient manner.

This paper is an extended version of the author’s earlier study. More details on the LTL and LWB are provided in the current study. The author introduces 17 new business rule templates and illustrates the utilisation of the new templates via a case study that belongs to a different domain area.

Representations of time are commonly used to construct narratives in visualisations of data. However, since time is a value-laden concept, and no representation can provide a full, objective account of “temporal reality”, they are also biased and political: reproducing and reinforcing certain views and values at the expense of alternative ones. This conceptual paper aims to explore expressions of temporal bias and politics in data visualisation, along with possibly mitigating user approaches and design strategies.

This study presents a theoretical framework rooted in a sociotechnical view of representations as biased and political, combined with perspectives from critical literacy, radical literacy and critical design. The framework provides a basis for discussion of various types and effects of temporal bias in visualisation. Empirical examples from previous research and public resources illustrate the arguments.

Four types of political effects of temporal bias in visualisations are presented, expressed as limitation of view, disregard of variation, oppression of social groups and misrepresentation of topic and suggest that appropriate critical and radical literacy approaches require users and designers to critique, contextualise, counter and cross beyond expressions of the same. Supporting critical design strategies involve the inclusion of multiple datasets and representations; broad access to flexible tools; and inclusive participation of marginalised groups.

The paper draws attention to a vital, yet little researched problem of temporal representation in visualisations of data. It offers a pioneering bridging of critical literacy, radical literacy and critical design and emphasises mutual rather than contradictory interests of the empirical sciences and humanities.

Organizational studies fail to examine organizations in terms of the several environments in which they operate, both internally and externally. That is, studies tend to focus on climate, or time, or trust, or leadership. This chapter builds on academic research that discusses organizational environments in ways that show all of these environments are important for organizational understanding, especially for organizational leadership. In particular, this chapter offers a paradigm of understanding organizational leadership realities through multi-level understanding of the organizational environments of climate, knowledge, ethnos, and time.

The chapter first discusses five enviroscapes – climate, knowledge, ethos, time, and leadership. Each of these enviroscapes has two phenotypes – business and commerce. Each of these enviroscapes, with its concomitant phenotypes, is used differently at multiple levels of management and leadership by senior managers, middle managers, and entry-level managers. The scope of organizational reach, in terms of global, regional, and local levels of analysis, provides additional context for the use of enviroscapes. After a review of the theoretical bases for each enviroscape, the chapter applies appropriate theory and models to an extended time case study of land purchase in Indonesia.

Rational time accompanies the onslaught of hyper-globalization. The Inuit of Arviat, Nunavut, paradoxically use rational time to resist rational time, setting aside temporal zones to protect Western cultural paradigms from impinging on their lives all of the time. Additionally, because temporal norms indicate membership in a group, doing time differently is one of the most effective ways in which to say “I’m not a part of your group!” While resisting rational clock-time, for example by walking off the job each day promptly at 4:59 pm, the Inuit of Arviat nevertheless have a myriad of clocks in their homes. This chapter explores their temporal resistance and the riddle of “why so many clocks in Arviat?”

Organizational studies of time tend to be done by academic researchers rather than practitioners. This chapter builds on academic research to provide a practitioner perspective by reviewing time situated in theory and constructing two phenotypes: timescapes of business and social time. These timescapes are defined by six dimensions, each with a social and business time parameter. Organizational business and social timescapes have different functions and applications. Timescapes, with their concomitant dimensions and sets of parameters, are used differently by senior managers, middle managers, and entry-level managers. Three multi-level approaches (self, dyadic, and social relationships), composition theory, and compilation theory confirm these three managerial timescape usages. After a review of the theoretical bases of the timescape constructs and a brief discussion of the grounded, anthropological, research methodology used in the study, this chapter applies timescape theory and models to an extended time case study of the Procter & Gamble Company that frames the company's timescape understanding and use from a practitioner's view.

The purpose of this paper is to introduce an approach for m‐valued classical and non‐classical (reversible and quantum) optical computing. The developed approach utilizes new multiplexer‐based optical devices and circuits within switch logic to perform the required optical computing. The implementation of the new optical devices and circuits in the optical regular logic synthesis using new lattice and systolic architectures is introduced, and the extensions to quantum optical computing are also presented.

The new linear optical circuits and systems utilize coherent light beams to perform the functionality of the basic logic multiplexer. The 2‐to‐1 multiplexer is a basic building block in switch logic, where in switch logic a logic circuit is implemented as a combination of switches rather than a combination of logic gates as in the gate logic, which proves to be less‐costly in synthesizing wide variety of logic circuits and systems. The extensions to quantum optical computing using photon spins and the collision of Manakov solitons are also presented.

New circuits for the optical realizations of m‐valued classical and reversible logic functions are introduced. Optical computing extensions to linear quantum computing using photon spins and nonlinear quantum computing using Manakov solitons are also presented. Three new multiplexer‐based linear optical devices are introduced that utilize the properties of frequency, polarization and incident angle that are associated with any light‐matter interaction. The hierarchical implementation of the new optical primitives is used to synthesize regular optical reversible circuits such as the m‐valued regular optical reversible lattice and systolic circuits. The concept of parallel optical processing of an array of input laser beams using the new multiplexer‐based optical devices is also introduced. The design of regular quantum optical systems using regular quantum lattice and systolic circuits is introduced. New graph‐based quantum optical representations using various types of quantum decision trees are also presented to efficiently represent quantum optical circuits and systems.

The introduced methods for classical and non‐classical (reversible and quantum) optical regular circuits and systems are new and interesting for the design of several future technologies that require optimal design specifications such as super‐high speed, minimum power consumption and minimum size such as in quantum computing and nanotechnology.