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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.

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.

End‐user demand information suffers from delay and distortion as it moves upstream in a supply chain. Co‐ordination between organisations in the supply chain, through sharing of demand information, is a possible solution to counter this distortion. Modelling and analysing supply chains, however, is not an easy task, as the supply chains contain multiple echelons and are faced with uncertain demand and lead‐times. For multi‐echelon supply chains adopting different inventory and forecasting policies at the echelon level, simulation is the most appropriate analysis tool. In this paper, we describe the development of a simulation workbench for modelling and analysing multi‐echelon supply chains. The workbench facilitates study of inventory and forecasting policies practised by the echelons, and models different information exchange mechanisms adopted by them. An experiment conducted, to test the workbench and demonstrate its capabilities, confirms that the workbench is a useful tool for gaining valuable insights into information exchange in a particular supply chain.

The purpose of this paper is to study a woodworking machine, in which a linear induction motor (LIM) is applied to feed the wood to be processed into the cutting saw. The LIM is optimally designed and the whole drive system is controlled by a programmable logic controller (PLC) to meet the industrial demands.

Since the operation range is short, the LIM mainly works at the transient state of quick start and quick brake. Hence, the thrust force with a large slip ratio (hereafter called the starting thrust) is one of the most important issues in the LIM design. Finite element method is used to optimize the starting thrust while taking a specific variable voltage variable frequency (VVVF) drive into account.

The LIM system directly drives the machine workbench where the wood is placed, eliminating the requirement of manpower to push the wood through the cutting saw, hence, greatly reduces the operation hazard. It has a higher reliability and longer service life than the conventional drive system employing a rotary motor with a ball screw mechanism.

The LIM is an attractive candidate for the woodworking machine application, which can replace the complicated and relatively low-efficiency mechanism of rotary motor and ball screw. High starting thrust can be achieved by optimizing the LIM design, whilst the specific VVVF control is essential to ensure a good drive performance. The PLC is competent for both human-machine interface (HMI) and control of the inverter-fed LIM system, and is of high reliability in industrial environment.

In the present worldwide situation, the survival of a business is a major crucial aspect. The business cannot be succeeded unless it produces the anticipated production levels. Achievement of this can be possible only by maintaining the equipment into an adequate level. Load-Haul-Dumpers (LHDs), as the main workhorse and massive transporting machines, are highly utilized in underground mining operations. Despite the usage of LHDs, these are prone to the uneven and unexpected occurrence of potential failures. These are causes to minimize the production and productivity of capital intensive equipment. To get a good profitability index, it is very necessary to have the required levels of equipment reliability and availability. Estimation of reliabilities and availabilities play a critical role in the performance evaluation of equipment.

By keeping the significance of the present research work in view in this research paper one of the well appropriate techniques such as fault tree analysis (FTA) was utilized to assess the reliability of the LHD system based on the function flow diagram. Best fit distribution of data sets were made by the utilization of Kolmogorov–Smirnov (K-S) test. Parametric estimation of theoretical probability distributions was done by utilizing the maximum likelihood estimation (MLE). Failure rate of each LHD system has computed based on the best fit results from “Isograph Reliability Workbench 13.0”. Reliability configuration of each LHD system has modeled using reliability block diagram (RBD), as well as the FTA.

Independent and identical distribution (IID) assumption of data sets was validated through statistic U-test (Chi Squared test). On the basis of test results, the data sets are in accordance with IID assumption. Therefore renewal process approach has been utilized for further investigation. Allocations of best fit distribution of data sets were made by the utilization ofK-S test. Parametric estimation of theoretical probability distributions was made by utilizing maximum likelihood estimation (MLE) method. Reliability of each individual subsystem has been computed according to the best fit distribution. The deductive method called RBD was utilized to investigate the given system reliability by analyzing with graphical representations of logic system and observed highest percentage of reliability as 69.44% (LH29). FTA has been utilized to investigate the availability percentage of a system and observed highest percentage value as 79.51% (LH29). This technique also helps to identify the most critical parts/cut sets by using Fussell-Vesely (F-V) importance measure.

As the reliability analysis is one of the complex techniques, it requires strategic decision-making knowledge for the selection of methodology to be used. As the present case study was from a public sector company, operating under financial constraints the conclusions/findings may not be universally applicable.

The present study throws light on this equipment that need a tailored maintenance schedules, partly due to the peculiar mining conditions, under which they operate. This analysis provides the information on several aspects such as present working condition of the machines, occurrence of various potential failure modes, influence of failure modes on its performance and reliable life aspects etc. Also, these investigations asses the forecasting of necessary managerial practices or control measures like possible design modifications and replacement actions of components to ensure the required levels of availability and utilization of the equipment. Both qualitative and quantitative analysis of FTA has been performed to determine the minimal/most influencing cut sets of the system and to estimate overall system availability within the work environment. Based on the computed results reasons for performance drop of each machine was identified and suitable recommendations were suggested to improve the performance of capital intensive systems.

The purpose of this paper is to understand the needs of humanists with respect to information and communication technology (ICT) in order to prescribe the design of an e‐humanist's workbench.

A web‐based survey comprising over 60 questions gathered the following data from 169 humanists: profile of the humanist, use of ICT in teaching, e‐texts, text analysis tools, access to and use of primary and secondary sources, and use of collaboration and communication tools.

Humanists conduct varied forms of research and use multiple techniques. They rely on the availability of inexpensive, quality‐controlled e‐texts for their research. The existence of primary sources in digital form influences the type of research conducted. They are unaware of existing tools for conducting text analyses, but expressed a need for better tools. Search engines have replaced the library catalogue as the key access tool for sources. Research continues to be solitary with little collaboration among scholars.

The results are based on a self‐selected sample of humanists who responded to a web‐based survey. Future research needs to examine the work of the scholar at a more detailed level, preferably through observation and/or interviewing.

The findings support a five‐part framework that could serve as the basis for the design of an e‐humanist's workbench.

The paper examines the needs of the humanist, founded on an integration of information science research and humanities computing for a more comprehensive understanding of the humanist at work.

The purpose of this study is to explore a new assembly process planning and execution mode to realize rapid response, reduce the labor intensity of assembly workers and improve the assembly efficiency and quality.

Based on the related concepts of digital twin, this paper studies the product assembly planning in digital space, the process execution in physical space and the interaction between digital space and physical space. The assembly process planning is simulated and verified in the digital space to generate three-dimensional visual assembly process specification documents, the implementation of the assembly process specification documents in the physical space is monitored and feed back to revise the assembly process and improve the assembly quality.

Digital twin technology enhances the quality and efficiency of assembly process planning and execution system.

It provides a new perspective for assembly process planning and execution, the architecture, connections and data acquisition approaches of the digital twin-driven framework are proposed in this paper, which is of important theoretical values. What is more, a smart assembly workbench is developed, the specific image classification algorithms are presented in detail too, which is of some industrial application values.

The purpose of this study is to propose an extended reliability method for an industrial motor drive by integrating the physics of failure (PoF).

Industrial motor drive systems (IMDS) are currently expected to perform beyond the desired operating conditions to meet the demand. The PoF of the subsystem affects its reliability under such harsh operating circumstances. It is crucial to estimate reliability by integrating PoF, which helps in understanding its impact and to develop a fault-tolerant design, particularly in such an integrated drive system. An integrated PoF extended reliability method for industrial drive system is proposed to address this issue. In research, the numerical failure rate of each component of industrial drive is obtained first with the help of the MIL-HDBK-217 military handbook. Furthermore, the mathematically deduced proposed approach is modeled in the GoldSim Monte Carlo reliability workbench.

From the results, for a 15% rise in integrated PoF, the reliability and availability of the entire IMDS dropped by 23%, resulting in an impact on mean time to failure (MTTF).

The integrated PoF of the motor and motor controller affects industrial drive reliability, which falls to 0.18 with the least MTTF (2.27 years); whose overall reliability of industrial drive drops to 0.06 if it is additionally integrated with communication protocol.

This paper aims to provide a service-based integrated prototype framework for the design of reusable modular assembly systems (RMAS) incorporating reusability of equipment into the process. It extends AutomationML (AML) developments for an engineering data exchange to integrate and standardize the data formats that support the design of RMAS.

The approach provides a set of systematic procedures and support tools for the design of RMAS. This includes enhanced domain knowledge models that facilitate the interpretation and integration of information across the design phases.

The inclusion of reusability aspects in the design phase improves the sustainability of future assembly systems, by ensuring equipment use until its end-of-life. Moreover, the integrated support tools reduce the design time, while improving the quality/performance of the system design solution, as it enables the exploration of a larger solution space. This will result in a better response to dynamic and rapidly changing system requirements.

This work provides a sustainable approach for the design of modular assembly systems (MAS), which will ensure better resource utilization. Additionally, the standardization of the data and the support of low cost tools is expected to benefit industrial companies, particularly the small- and medium-sized enterprises.

This approach offers a service-based platform which uses production data to incorporate reusability aspects into the design process of modular assembly system. Moreover, it provides a framework for modular assembly system design by extending the current design processes and interactions between stakeholders. To support this, a standardized method for information representation and exchange across the several phases of the RMAS design activity is briefly illustrated with an industrial case study.