Towards Personalised Home Care Systems

Home care is increasingly seen as a promising alternative to traditional care services. Programming home care systems remains a significant challenge considering the potentially large scale of deployment, the differences between individual care needs, and the progressive nature of ageing. In this paper, we present ongoing work on programming home care systems to support personalisation, adaptability over time, and dependability. A policy-based approach is used to build such systems. We present the technical details of our approach, including a policy language for home care and the corresponding system architecture. Policy examples are used to illustrate how the approach supports personalisation of home care services

Modular Feature Specification

CRESS (CHISEL Representation Employing Systematic Specification) is a notation and set of tools for graphical specification and analysis of features. It is applicable wherever a system consists of base functionality to which are added optionally selected features. The CRESS notation is introduced for basic diagrams, feature diagrams, and rules governing their behaviour. Although telephony is used to illustrate the approach, CRESS is not limited to this domain. The structure and use of the portable CRESS toolset is explained. CRESS can generate code for a variety of target languages. The strategy for translation to LOTOS is presented, along with some techniques for analysing the generated specifications

An Architectural Foundation for Relating Features

Consideration of services in the Intelligent Network and telecommunications leads to the definition of ANISE (Architectural Notions In Service Engineering). This is a rigorous language for defining services systematically using a hierarchy of constituent features. The basic telephone call is used as an illustrative example, supplemented by a number of variations that show how ANISE can easily cope with changes to the basic call. An indication is given of how this might be used to detect problem areas that may lead to feature interaction

Constraint-Oriented Style in LOTOS

The concept of a constraint-oriented specification style is presented in general terms and with respect to the ISO Formal Description Technique LOTOS (Language Of Temporal Ordering Specification). The constraint-oriented style has proven very suitable for specifying the abstract, implementation-independent behaviour of systems in a modular fashion. The essential idea behind constraint-oriented specification is separation of concerns, which is facilitated by the behaviour combinators of LOTOS. The constraint-oriented style is illustrated by giving a highly-structured specification in LOTOS of the well-known AB (Alternating Bit) Protocol

The Invoicing Case Study in (E-)LOTOS

The informal requirements for the invoicing case study are analysed and interpreted. This leads to a high-level specification architecture that can be formalised. Specifications are presented in LOTOS (Language Of Temporal Ordering Specification). For comparison, specifications are also presented E-LOTOS (Enhancements to LOTOS) – the new version of LOTOS currently being standardised. Since LOTOS allows a balance to be struck between process-oriented and data-oriented modelling, specifications in both styles are given. The resulting specifications are evaluated in the context of LOTOS and formal approaches more generally

Relating Services and Features in the Intelligent Network

The services and features of the Intelligent Network Capability Set 1 are briefly introduced. The service-feature relationship is analysed and simplified. This leads to the synthesis of a new multi-level relationship between services and features, allowing a more consistent construction of services from their components

Formally-Based Testing of Radiotherapy Accelerators

The paper presents the aims and research plan of the CONFORMED project (Conformance Of Radiological/Medical Devices). This three-year project will develop tools and techniques for modelling and testing radiotherapy equipment. Formal specifications in LOTOS (Language Of Temporal Ordering Specification) will be used to model accelerators formally and to derive tests rigorously based on these specifications

Formalising the Chisel Feature Notation

The CHISEL notation was developed by Bellcore as an informal graphical notation for describing telecomms services and features. CRESS (CHISEL Representation Employing Systematic Specification) is an enhanced version of CHISEL with tightly defined rules for the syntax and static semantics of diagrams. More importantly, CRESS has formal denotations given by SDL (Specification and Description Language) and LOTOS (Language Of Temporal Ordering Specification). This permits rigorous checking, analysis and prototyping of descriptions. The accompanying toolset has been written in an open and extensible manner

An engineering approach to formal methods

The distinctive features of engineering are discussed, and used to identify how an engineering approach to formal methods might be developed. The key concept in engineering is suggested to be known components that are combined in known ways. This component-based style is illustrated for two application areas at two levels: in high-level specification of communications services, and in low-level specification of digital logic. The underlying formal language is LOTOS (Language Of Temporal Ordering Specification)

Validating Architectural Feature Descriptions using LOTOS

The phases of the ANISE project (Architectural Notions In Service Engineering) are briefly explained with reference to the work reported here. An outline strategy is given for translating ANISE descriptions to LOTOS (Language of Temporal Ordering Specification), thus providing a formal basis. It is shown how modular ANISE descriptions of features can be defined and then merged. Potential feature interactions can be identified statically through structural overlaps. A scenario language is introduced to express validation tests for features in a modular fashion, and a number of examples are given. Scenarios are automatically translated to LOTOS and analysed through LOTOS simulation. This allows features to be validated in isolation, and dynamically in combination with other features. The design of the translation and validation tools is discussed, showing typical results when investigating feature descriptions. The paper concludes with a guide to extending the approach for new features