Russell Lock

QoSOnt: a QoS ontology for service-centric systems

This paper reports on the development of QoSOnt: an ontology for quality of service (QoS). Particular focus is given to its application in the field of service-centric systems. QoSOnt is being developed to promote consensus on QoS concepts, by providing a model which is generic enough for reuse across multiple domains. As well as the structure of the ontology itself an example application currently in development - SQRM (service QoS requirements matcher) - is discussed. This application is used to highlight some of the advantages of the ontology including standardisation and the level of machine understanding of QoS specifications which can be achieved.

Deriving Information Requirements from Responsibility Models

This paper describes research in understanding the requirements for complex information systems that are constructed from one or more generic COTS systems. We argue that, in these cases, behavioural requirements are largely defined by the underlying system and that the goal of the requirements engineering process is to understand the information requirements of system stakeholders. We discuss this notion of information requirements and propose that an understanding of how a socio-technical system is structured in terms of responsibilities is an effective way of discovering this type of requirement. We introduce the idea of responsibility modelling and show, using an example drawn from the domain of emergency planning, how a responsibility model can be used to derive information requirements for a system that coordinates the multiple agencies dealing with an emergency.

Modelling and Analysis of Socio-Technical System of Systems

This paper proposes a novel approach to System of Systems modelling based on the specification of system capabilities. The approach is designed to help end users graphically identify and analyse the hazards and associated risks that can arise in complex socio-technical System of Systems, with particular emphasis on the role of system dependencies. Through a case study this paper shows how the technique can identify the vulnerabilities that may arise within a given System of System configuration; and explore the resilience of a given system when considering evolution and unexpected circumstances.

Developing a methodology to support the evolution of System of Systems using risk analysis

The potential for uncontrolled evolution of member systems is one of the most significant challenges facing SoS (System of Systems) management. Lack of control in evolution makes organizations more inefficient, raises costs, and can affect their ability to adapt quickly to changing circumstance. SoS bring together individual systems to fulfill shared goals, but the systems are likely to have been developed independently, and to different development and operational standards. Member systems retain much of their autonomy, along with their motivations and goals. This increases the risk of decisions relating to evolution being taken unilaterally within member systems, potentially to the detriment of the stability, efficiency and dependability of the SoS. This paper proposes a methodology to support non specialist end users in the identification, organization and discussion of information required to manage SoS evolution, and uses a modified form of HAZOPS (Hazard and Operability Study) to analyze the associated risks of evolution. The paper evaluates the methodology using a case study based on a recent RAF (Royal Air Force) Nimrod air crash, the official investigation into which showed severe failings in the operation of the Nimrod SoS. The paper concludes that the methodology proposed would provide valuable support to SoS evolution processes, and discusses future directions for the research.

Individual variables with an impact on knowledge sharing: the critical role of employees’ ignorance

Purpose – The purpose of this paper is to identify individual variables with an impact on knowledge sharing and explore the under-discussed construct of employees’ ignorance. This can enhance the knowledge-sharing process and facilitate the development of greater intellectual capital. Design/methodology/approach – Eighty-four dependent variables affecting knowledge sharing are analyzed and classified into 11 categories. In addition, the direct effect of employees’ ignorance on knowledge sharing is introduced and empirically investigated in a case study of a multinational organization operating within the aerospace and defense industry. Findings – The findings suggest that employees’ ignorance may negatively affect their intention to share knowledge, thus leading to poor decision-making and communication in organizations. Employees’ ignorance could also limit the organizational ability to repel external threats, implement innovation and manage future risks. Originality/value – A classification scheme based...

OBSERVATIONS OF THE SCOTTISH ELECTIONS 2007

In the recent Scottish elections, an e-counting system was employed to manage the increased complexity of the Scottish electoral system. The elections were also the first to allow members of the public to register as election observers, accredited by the Electoral Commission. This paper discusses some of the issues that arose during observations made by the authors as observers, relating to the use of the new e-counting system.

Information requirements for enterprise systems

In this paper, we discuss an approach to system requirements engineering, which is based on using models of the responsibilities assigned to agents in a multi-agency system of systems. The responsibility models serve as a basis for identifying the stakeholders that should be considered in establishing the requirements and provide a basis for a structured approach, described here, for information requirements elicitation. We illustrate this approach using a case study drawn from civil emergency management.

Automated Negotiation for Service Contracts

Automated negotiation draws upon research from a number of different computing disciplines, predominantly those of game theory, AI, requirement specification & authorisation research. Automated negotiation allows clients/services to come to agreements regarding service utilisation. A number of problems exist within the area, primarily those of requirement elicitation and trust. These problems can be minimised through standardisation and careful design; however, human participation in the process cannot be completely removed. This paper examines a possible format, architecture and implementation (TRANSACT) to aid in the automated negotiation of service contracts based on exogenously stated requirements/capabilities. In doing so it explores the issues and areas in which further developments are required to support future service developments

An approach to compute user similarity for GPS applications

The proliferation of GPS enabled devices has led people to share locations both consciously and unconsciously. Large spatio-temporal data comprising of shared locations and whereabouts are now being routinely collected for analysis. As user movements are generally driven by their interests, so mining these mobility patterns can reveal commonalities between a pair of users. In this paper, we present a framework for mining the published trajectories to identify patterns in user mobility. In this framework, we extract the locations where a user stays for a period of time popularly known as stay points. These stay points help to identify the interests of a user. The statistics of pattern and check-in distributions over the GPS data are used to formulate similarity measures for finding K-nearest neighbors of an active user. In this work, we categorize the neighbors into three groups namely strongly similar, closely similar and weakly similar. We introduce three similarity measures to determine them, one for each of the categories. We perform experiments on a real-world GPS log data to find the similarity scores between a pair of users and subsequently find the effective K-neighbors. Experimental results show that our proposed metric outperforms existing metrics in literature.

Repetition between stakeholder (user) and system requirements

Stakeholder requirements (also known as user requirements) are defined at an early stage of a software project to describe the problem(s) to be solved. At a later stage, abstract solutions to those problems are prescribed in system requirements. The quality of these requirements has long been linked to the quality of the software system and its development or procurement process. However, little is known about the quality defect of redundancy between these two sets of requirements. Previous literature is anecdotal rather than exploratory, and so this paper empirically investigates its occurrence and consequences with a case study from a UK defense contractor. We report on a survey of sixteen consultants to understand their perception of the problem, and on an analysis of real-world software requirements documents using natural language processing techniques. We found that three quarters of the consultants had seen repetition in at least half of their projects. Additionally, we found that on average, a third of the requirement pairs’ (comprised of a system and its related stakeholder requirement) description fields were repeated such that one requirement in the pair added only trivial information. That is, solutions were described twice while their respective problems were not described, which ultimately lead to suboptimal decisions later in the development process, as well as reduced motivation to read the requirements set. Furthermore, the requirement fields considered to be secondary to the primary “description” field, such as the “rationale” or “fit criterion” fields, had considerably more repetition within UR–SysR pairs. Finally, given that the UR–SysR repetition phenomena received most of its discussion in the literature over a decade ago, it is interesting that the survey participants did not consider its occurrence to have declined since then. We provide recommendations on preventing the defect, and describe the freely available tool developed to automatically detect its occurrence and alleviate its consequences.