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Semiconductor devices and systems containing them have become so complex that it is difficult and costly to test them adequately. The solution is to design them to be testable. In this the author considers testability cost trade‐offs, outlines the interrelationship of test programming and designing for testability, and presents several methods of designing for testability.

To investigate how far sociocyberneticians have tried to meet the criterion of “empirical testability” in their publications. What changes in this respect have taken place in recent years?

Inventory of papers published in Kybernetes from 1977 to 2004, and classification of sociocybernetic papers by type, i.e. the degree to which empirical testability plays a role in the argument.

The number of sociocybernetic papers has increased. The purely conceptual, theoretical or methodological papers make way for papers in which particular social systems and processes are analyzed, using the conceptual apparatus of cybernetics. However, the percentage of papers in which empirical data are used for the testing of hypotheses and models has decreased. It seems that the testability problem of sociocybernetics is unsolvable.

These findings lead to a reflection on the way in which sociocybernetics could eventually overcome the testability problem, by more methodological sophistication, on the one hand, and a more parsimonious formulation of sociocybernetic theories, on the other hand.

Theories in sociocybernetics usually have a high degree of complexity, which may lead to methodological problems when these theories are tested in confrontation with “real world data”. From a review of the literature it appears that only a small percentage of the sociocyberneticians make an attempt to test their theory empirically. Two alternative approaches are used: the deduction from the theory of a series of univariate and bivariate hypotheses, subsequently tested with the usual statistical methods; and the reformulation of the theory into a simulation model and comparing the trajectories generated by the computer with time series of “real world data”;. Both approaches have their advantages and risks. It is shown in a simulation experiment that the inclusion of various sociocybernetical ideas (self‐referencing, goal‐referencing, morphogenesis) leads to a model with many degrees of freedom, and consequently of a large “no man’s land” in between the set of “verifiers” and the set of “falsifiers” of the theory.

The purpose of this paper is to propose a model for assisting in the decision-making process for acquiring a condition monitoring (CM) system for an oil-immersed power transformer in order to improve its maintainability.

The proposed model is based on the analytic hierarchy process. The assessment was performed by pairwise comparisons, and a sensitivity analysis (what-if analysis) was used to identify the implications of changing the criteria weights. In order to select the criteria and alternatives, a search was conducted for the power transformer failure modes, monitored parameters and CM technologies.

The proposed model provides a structured solution for a complex problem: deciding the best combination of technologies for CM of power transformers.

Because the pairwise comparisons were done only by the author, the results may need to be improved with the assessment of more experts. Also, it was done for a specific type of transformer; it might be necessary to customise the alternatives for other cases. Finally, as a future consideration, more levels can be added to the hierarchy to improve the accuracy of the model.

The power transformer is an asset where the most appropriate maintenance strategy for it is condition-based maintenance. In order to improve its maintainability, it is recommendable to improve its testability and diagnosability. For achieving this goal, the maintenance personnel have to decide the best combination of technologies for CM. The methodology developed can assist the decision makers to select the most appropriate cost-benefit strategy.

The paper presents a structured and generic method of selecting the most appropriate CM system for power transformers.

Automatic in‐circuit testing is a cost effective facility for not only testing assembled printed circuit boards but for providing component level diagnostics very quickly with an average PCB test time of less than 30 seconds. The in‐circuit tester relies on a customised fixture (essentially a bed‐of‐nails) to interface particular PCBs to the system and a computer programme to control the hardware to test all the individual components on the PCB to their own specification irrespective of how the circuitry is configured. So if all the individual components work and are interconnected correctly, the complete assembly should function correctly. Traditionally the fixture requirements for most PCBs have been straightforward. In general, components are mounted on only one side of the board allowing easy access to the other side where all the tracks may be accessed by a bed of nails. However, the introduction of surface mount technology introduces mechanical restraints on this concept. Components can be mounted on both sides of the PCB, possibly causing an access problem. Not all circuit interconnections may be available on a single side of the PCB, necessitating dual side fixturing. The pitch of components together with pad and track sizes has dramatically reduced, possibly requiring the use of smaller test probes and certain SMDs do not allow direct probing at all. All these things can present problems but they do not mean that in‐circuit testing is no longer the solution to the test and repair problem. On the contrary, it is particularly well suited to the production problems being experienced by manufacturers. And where components are difficult to remove and replace on a PCB, it is particularly important that the fault diagnosis is to component level. This paper describes the problem in detail and goes on to demonstrate that if a code of practice is followed within the design of a new PCB, then there need not be a problem. Much can be achieved very simply within the design that can improve the testability of PCBs so that in‐circuit testing remains a very cost effective system. Experience demonstrates that most designs could be fixtured with traditional techniques and that means cheap and reliable fixturing.

This paper aims to reproduce the electrical connector intermittent fault behaviours with step-up vibration stress while maintaining the integrity of the product.

A dynamic model of an electrical connector under vibration is established for contact resistance analysis. Next, the dynamic characteristics of contact resistance are analysed, and cumulative damage theory is used to calculate the damage under different stresses during the intermittent fault reproduction test. To reduce damage and improve efficiency, the step-up stress is used for the reproduction test.

The proposed method can reproduce the intermittent fault behaviour, and the step-up stress test is more efficient than the constant stress test.

Step-up stress is used for intermittent fault reproduction, and the quantitative relationships between intermittent fault and product damage can be further studied.

It is expected that the proposed methodology can help engineers to reproduce the intermittent fault behaviours to facilitate the detection and diagnosis of intermittent fault and to improve equipment safety.

The mechanism of electrical connector reproduction is analysed and the step-up stress test is used for intermittent fault reproduction.

States that current pricing strategies used in the service industries are often too simplistic and ineffective in the face of complex environmental conditions. Introduces the Pricing Differentiation Premium Model, which includes in the firm′s pricing strategy its ability to differentiate itself from competitors. Discusses possible strategies for influencing differentiation premiums which can improve the pricing discretion of the service provider.

Surface Mounting Technology becomes more essential with increasing pin count of ICs. The opportunities for improved performance, miniaturisation and cost are being exploited largely in Japan and increasingly in the USA, but there remains a lack of comprehension and vision in our own community. Nevertheless, there are some very promising developments of packaging and interconnection in the UK and in Europe. While substrates for hybrids and PCBs are heading towards standard Eurocard size, micropackage types are still proliferating rather than consolidating on a preferred standard. Assemblies of these increasing pin‐count components can be soldered reliably, and improved techniques continue to be developed. Quality and reliability of such assemblies are increasingly aided by on‐line vision and inspection procedures including optical, X‐ray and infra‐red techniques. The compactness and complexity require the emerging solutions in design‐for‐testability. Testability and built‐in self‐test revive the viability and emerging trend towards chip‐on‐board (formerly the well established bare‐chip‐and‐wire hybrid technology), now incorporating VLSI and supported by more advanced interconnections including advanced TAB and integrated thin‐film active devices.

Testing has become one of the dominant costs in the process of bringing a product from initial conception to the market place. Because of this, it is now imperative that the impact of any technology change on the test process is considered at an early stage. In this light, the increasing trend towards the use of surface‐mounting techniques in the fabrication of electronic systems is examined, with particular emphasis on the consequences on product testing during design validation, manufacture and repair. The aim is to highlight areas in which new attitudes and replacements for traditional solutions will be needed if surface‐mounting techniques are to be as cost‐effective as possible.

The purpose of this paper is to explore the scientific nature of work-based learning (WBL) and research as operationalized in Professional Studies by examining first principles of scientific inquiry.

This paper introduces a Professional Studies program as it has been implemented at University of Southern Queensland in Australia and examines it from the perspective of five first principles of scientific inquiry: systematic exploration and reporting, use of models, objectivity, testability and applicability. The authors do so not to privilege the meritorious qualities of science or to legitimise WBL or its example in Professional Studies by conferring on them the status of science, but to highlight their systematised approach to learning and research.

If the authors define Professional Studies to mean the systematic inquiry of work-based people, processes and phenomena, evidence affirmatively suggests that it is scientific “in nature”.

WBL has been well documented, but its orientation to research, particularly mixed methods (MM) research through Professional Studies, and its adherence to first principles of science have never been explored; this paper begins to uncover the value of work-based pedagogical approaches to learning and research.