Socio-technical systems: From design methods to systems engineering

It is widely acknowledged that adopting a socio-technical approach to system development leads to systems that are more acceptable to end users and deliver better value to stakeholders. Despite this, such approaches are not widely practised. We analyse the reasons for this, highlighting some of the problems with the better known socio-technical design methods. Based on this analysis we propose a new pragmatic framework for socio-technical systems engineering (STSE) which builds on the (largely independent) research of groups investigating work design, information systems, computer-supported cooperative work, and cognitive systems engineering. STSE bridges the traditional gap between organisational change and system development using two main types of activity: sensitisation and awareness; and constructive engagement. From the framework, we identify an initial set of interdisciplinary research problems that address how to apply socio-technical approaches in a cost-effective way, and how to facilitate the integration of STSE with existing systems and software engineering approaches.     

RPC in Windows systems: what you don't know could hurt you

The vulnerabilities of the remote procedure call (RPC) in Windows were exposed with devastating effect last year by the MSBlaster worm. This paper examines RPC in detail and suggests some ways to protect this widely used and useful protocol.     

IEEE 1220: for practical systems engineering

IEEE 1220 guides enterprises or projects to a well-engineered solution for product-oriented systems. Annex C describes how to success fully use IEEE 1220 together with ISO/IEC 15288, but there are still gaps to bridge to fully harmonize the two standards. Although a "fast-track" ballot of IEEE Std 1220-2005 is currently under way in JTC1, planning joint committee activities to produce a coordinated IEEE-ISO/IEC version of IEEE 1220 should allow for completion of the ISO/IEC 15288:2002.     

An integrated modelling approach for the representation and embodiment of engineering systems with standard components

In todays global markets the commercial success of a product, however defined, is highly dependent upon the rapid and efficient transformation of an engineering system from a design schema to a fully embodied optimal solution. The ability of the designer to achieve this is severely frustrated by the analytically intensive and time-consuming aspects of embodying a concept. This is particularly the case where standard components have to be considered. This paper presents a new modelling approach that supports the designer during the transformation of a concept to an embodied solution. This modelling approach provides for the representation of conceptual schemas and their subsequent embodiment with standard components from third-party electronic representations. The modelling strategies and associated software issues for representing a mechanical system, handling the interactions between components and incorporating the governing representations for the design and selection of individual components are discussed. The process of constructing a system model, specifying the desired performance characteristics and the process of system resolution are also described. The paper concludes with an industrial case study which is used to demonstrate the capabilities and potential of the new approach for supporting the embodiment of systems and the important task of design synthesis.     

ABE: an environment for engineering intelligent systems

The ABE multilevel architecture for developing intelligent systems addresses the key problems of intelligent systems engineering: large-scale applications and the reuse and integration of software components. ABE defines a virtual machine for module-oriented programming and a cooperative operating system that provides access to the capabilities of that virtual machine. On top of the virtual machine, ABE provides a number of system design and development frameworks, which embody such programming metaphors as control flow, blackboards, and dataflow. These frameworks support the construction of capabilities, including knowledge processing tools, which span a range from primitive modules to skeletal systems. Finally, applications can be built on skeletal systems. In addition, ABE supports the importation of existing software, including both conventional and knowledge processing tools     

Design of joint systems: a theoretical challenge for cognitive systems engineering

In this paper the “joint systems approach” will be discussed. The approach is considered as a new paradigm in cognitive systems engineering (CSE). Its central idea, that human and technology form a functional unity, is as such not new. Why, then, has this idea become so appealing right now? In the first part of the paper we seek answers to this question by analysing the current situation in product design. The conclusion is that the focus of design is shifting from single products to intelligent environments. This change in focus induces tensions into the design process that urge for solutions. One of them is re-conceptualising the relationship between human and technology, precisely what the joint system approach is about. Three different joint system approaches are considered: the joint cognitive systems approach (JCS), the Risö extended CSE approach, and the joint intelligent systems (JIS) approach proposed by us. Comparisons are made with regard to how these approaches understand the joint system to be organised. While the JCS approach focuses on the human–technology relationship, the other two consider this relationship as embedded in a context of object-oriented activity. As a consequence, environment becomes included in the joint system. In JIS approach we propose the use of the semiotic concept of habit to characterise the ways of functioning of the joint system. “Habit” is a tool for identifying generic patterns in the situation-specific behaviour of the system. Defining habits enables expressing the meaning or purpose of the system’s functioning. In the end of the paper, we propose a design process model for the development of JIS. This approach is aimed at designing systems in usage i.e. to design of practices.     

Self-maintenance and engineering immune systems: Towards smarter machines and manufacturing systems

This paper discusses the state-of-the-art research in the areas of self-maintenance and engineering immune systems (EIS) for machines with smarter adaptability to operating regime changes in future manufacturing systems. Inspired by the biological immune and nervous systems, the authors are introducing the transformation of prognostics and health management (PHM) to engineering immune systems (EIS). First, an overview on PHM is introduced. Its transformation toward resilient systems, self-maintenance systems, and engineering immune systems is also discussed. Finally, new concepts in developing future biological-based smarter machines based on autonomic computing and cloud computing are discussed.     

Risk-based systems security engineering: stopping attacks with intention

In most modern information systems (IS), functionality and security are competing design goals. Therefore, system designers are constantly forced to make security-related trade-off decisions. Systems security engineers must build systems that are secure against real-world attacks without overengineering against any particular one. By understanding which attacks are most likely and which risks are most serious, system designers can make informed security-related trade-off decisions. We describe a systems security engineering methodology designers can use to make these decisions.     

PACT: an experiment in integrating concurrent engineering systems

The Palo Alto Collaborative Testbed (PACT), a concurrent engineering infrastructure that encompasses multiple sites, subsystems, and disciplines, is discussed. The PACT systems include NVisage, a distributed knowledge-based integration environment for design tools; DME (Device Modeling Environment), a model formulation and simulation environment; Next-Cut, a mechanical design and process planning system; and Designworld, a digital electronics design, simulation, assembly, and testing system. The motivations for PACT and the significance of the approach for concurrent engineering is discussed. Initial experiments in distributed simulation and incremental redesign are reviewed, and PACT's agent-based architecture and lessons learned from the PACT experiments are described     

Knowledge-based systems in civil engineering: Three case studies

Although substantial advances have been achieved in last twenty years, in practice we are still far from taking full advantage of the potential of knowledge-based systems (KBS). Very few KBS have survived their evaluation period and only one third of those that were initially reported as successful are still in use. The primary purpose of the paper is to report on three KBS applications that have been developed for research purposes in the field of civil engineering. The main challenge underlying all three projects has been to develop computer support systems that would induce changes and improvements to the way that engineers solve their everyday problems. A great deal of effort has been put into eliciting knowledge and reasoning strategies from engineering experts with the aim of building up a computer model of their expertise in order to assist engineers in their decision-making processes. The paper closes by highlighting the principal achievements and the main issues concerning the future development of KBS for solving real life problems.     

Reconfigurable handling systems as an enabler for large components in mass customized production

Manufacturing companies today are exposed to increasingly dynamic market requirements. Particularly in high-wage countries, there is also a clear trend toward standing out from global competitors by means of product differentiation. At the same time, however, prices have to remain competitive. As a consequence, many companies choose a mass customization strategy to reconcile individualized products with advantages of the economies of scale. So far, this aim is mainly reached in the consumer goods sector by flexible production systems with a high degree of automation. The approach presented here is capable of transferring the benefits of mass customization to large products with lower production quantities such as aircraft by means of a highly reconfigurable automated handling system. Instead of manual operations or specific jigs and fixtures for each component, the new system is characterized by supporting large work pieces at several distributed points by multiple robotic arms. The individual robots are simple in design and very lightweight so that they can be easily switched in order to reconfigure the assembly system for different tasks. The development does not only comprise hardware construction, but also new methods for programming, commissioning and control of cooperating handling devices in a modular and reconfigurable system layout.     

Designing for operations: Towards a sociotechnical systems and cognitive engineering approach to concurrent engineering

In the practice of concurrent engineering, the factors that are considered early in the product design process include manufacturability, assembly, and cost. A set of issues that are not typically considered revolve around the operational requirements for human workers in the manufacturing system. What tasks will human workers accomplish? How will these tasks be organized and coordinated? What information and resources need to be shared? Will the workers have a coherent set of job responsibilities? How should the manufacturing environment be designed to support effective work practices? How can a manufacturing process be designed that also informs organizational structure and takes into account the quality of working life?

The field of sociotechnical systems theory (STS) focuses on exactly these kinds of issues. Rather than subscribing to the usual view of technological determinism — that a complex human-machine system is designed solely with respect to optimization of technical criteria — the goal of STS is to jointly optimize both human and technological considerations in system design and operation. The spirit of STS has much in common with recent work in cognitive systems engineering that advocates the design of joint cognitive systems in which machines serve as flexible, context-sensitive resources for human problem solving. Furthermore, a focus on design teams necessitates the study of the relationship between group work and technology as studied in the field of computer-supported cooperative work (CSCW). This paper briefly reviews current research in sociotechnical systems theory, computer-supported cooperative work, and cognitive systems engineering and proposes a framework for integrating operational concerns into the concurrent engineering process. Relevance to industry

To be competitive, organizations need to effectively manage human and technological resources. A key issue is the nature of the information and technological infrastructure that both enables and supports ‘best practice’ across the enterprise. This paper describes such an approach in the context of the ‘operational enterprise’ and provides both a philosophical stance as well as specific examples of software support.     

GLASS: remote monitoring of embedded systems in power engineering

Internet technology is reaching industrial embedded systems first by providing remote access to them. The GLASS system supports remote monitoring capabilities for facilities ranging from large plants to devices on mobile platforms like trains     

Maximum flow and critical cutset as descriptors of multi-state systems with randomly capacitated components

Let G = (V, E, s, t) denote a directed network with node set V, arc set E = {1,…, n}, source node s and sink node t. Let Γ denote the set of all minimal s−t cutsets and b₁(τ), …, B_n(τ), the random arc capacities at time τ with known joint probability distribution function. Let Λ(τ) denote the maximum s−t flow at time τ and D(τ), the corresponding critical minimal s−t cutset. Let Ω denote a set of minimal s−t cutsets. This paper describes a comprehensive Monte Carlo sampling plan for efficiently estimating the probability that D(τ)εΩ-Γ and x<λ(τ)y at time τ and the probability that D(τ) Ω given that x < Λ(τ) y at time τ. The proposed method makes use of a readily obtainable upper bound on the probability that Λ(τ) > x to gain its computational advantage. Techniques are described for computing confidence intervals and credibility measures for assessing that specified accuracies have been achieved. The paper includes an algorithm for performing the Monte Carlo sampling experiment, an example to illustrate the technique and a listing of all steps needed for implementation.     

The allegory of the humidifier: ROI for systems engineering

Convincing management of the importance of systems engineering-making time available in the project schedule for systems analysis, generating specifications that define customer needs, and other arguments-always made sense to systems engineers from a risk reduction and cost-avoidance perspective. But as schedule crunches, today's fire drill, and project cost reductions take hold, systems engineering often takes a back seat to getting the hardware out the door. This company could not afford the time and money up front to systems engineer a valid approach. It thus made an initial decision not to invest in a solution that, in the long run, would have avoided an additional 10X to 50X in costs. Repetitive and ineffective bandage solutions, slipped program schedules, and unknown amounts in lost productivity cost real money, too