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In the search for on or off‐line methods for condition monitoring of wear sensitive components, Thin Layer Activation (TLA) has much to offer. It is possible to measure very small surface losses directly, and by the use of double layer, or direct, or indirect sentinel layer modifications, wear of material to any depth can be measured. The technique can be applied to most materials and extended to virtually all materials and components by the use of treated plugs or inserts. Material loss can often be measured under operating conditions without dismantling equipment. The technique is reliable and of known useful life, ie there can be no electrical or mechanical failures of the implanted layer. The total radioactivity is very low and no modification of material surface properties is likely. The use of TLA in condition monitoring will speed up the identification of incipient faults.

Modern corrosion monitoring is characterised by advancing technology and corresponding increasing complexity and is subject to many regulatory requirements, all of which can combine to impact on costs. In this environment it is essential that the material and services are designed, manufactured and provided so as to conform to the requirements of the purchasers and that the activities involved are carried out as economically as practicable. New concepts and disciplines continue to emerge to help the achievement of these objectives. Significant among these is one that is collectively identified in most countries as Quality Management.

One of the factors giving rise to failure of steel reinforced aluminium power line conductors (ACSR) is corrosion due to the loss of zinc galvanising from the steel. As the zinc coating deteriorates, so galvanic corrosion of the aluminium sets in, resulting in weakening of the conductor, overheating and eventual failure. The corrosion occurs within the conductor and is caused by the ingress of pollution and moisture to the interface between the aluminium and the galvanised steel strands. (Ref 1,2). Originally, conductors were manufactured from dry strands but in later conductors the strands (except the outer layer) were bitumen or grease coated to improve resistance of degradation. Methods of identifying internal corrosion in ACSR includes infrared scanning of energised lines, conductor diameter measurements and visual examination. Corrosion is usually well advanced before it is identified by these methods. In order therefore to obtain early warning of internal corrosion, a specialised corrosion detector based on the measurement of eddy currents was developed by the Central Electricity Generating Board. (Ref 1). This Overhead Line Corrosion Dector (OHLCD) has been brought to the market place by CORMON Ltd and this paper describes the construction and operation of the commercial system.

Ubiquitous web applications (UWA) are a new type of web applications which are accessed in various contexts, i.e. through different devices, by users with various interests, at anytime from anyplace around the globe. For such full‐fledged, complex software systems, a methodologically sound engineering approach in terms of model‐driven engineering (MDE) is crucial. Several modeling approaches have already been proposed that capture the ubiquitous nature of web applications, each of them having different origins, pursuing different goals and providing a pantheon of concepts. This paper aims to give an in‐depth comparison of seven modeling approaches supporting the development of UWAs.

This methodology is conducted by applying a detailed set of evaluation criteria and by demonstrating its applicability on basis of an exemplary tourism web application. In particular, five commonly found ubiquitous scenarios are investigated, thus providing initial insight into the modeling concepts of each approach as well as to facilitate their comparability.

The results gained indicate that many modeling approaches lack a proper MDE foundation in terms of meta‐models and tool support. The proposed modeling mechanisms for ubiquity are often limited, since they neither cover all relevant context factors in an explicit, self‐contained, and extensible way, nor allow for a wide spectrum of extensible adaptation operations. The provided modeling concepts frequently do not allow dealing with all different parts of a web application in terms of its content, hypertext, and presentation levels as well as their structural and behavioral features. Finally, current modeling approaches do not reflect the crosscutting nature of ubiquity but rather intermingle context and adaptation issues with the core parts of a web application, thus hampering maintainability and extensibility.

Different from other surveys in the area of modeling web applications, this paper specifically considers modeling concepts for their ubiquitous nature, together with an investigation of available support for MDD in a comprehensive way, using a well‐defined as well as fine‐grained catalogue of more than 30 evaluation criteria.

By increasing the digitalization of commercial services citizens' expect more from public services. First of all, this study will strive to identify which problems citizens encounter when they use a complex public service: preparation of an application for a building permit. In the light of the popularity of omnichannel approaches, the study then explores how omni-channel could help to address the problems which have been identified.

We implement the first phases of an action design science research project. We collect data both from citizens and public agencies and frame them as transparency problems. These abstract problems are then addressed by an omnichannel service provision as an abstract solution. The abstract solution is then instantiated in a design in the form of a user scenario developed in collaboration with current and future public officials.

The analysis uncovers multiple transparency issues: it distinguishes between process, case, language, cross-channel and cost transparency. One root cause of the transparency issues observed is the lack of service transparency which defines the purpose and scope of a ser-vice. We therefore recommend defining a service-strategy before informational and technical aspects of an omnichannel approach can be implemented. Following this strategy, omnichannel offers public administrations unique opportunities to excel in citizens' service provision.

The study provides insights into how citizens view complex public services. For researchers, this study offers the conceptualization as transparency issues. Practitioners from the public administrations can also benefit from the concept and vision of omnichannel public services.

This purpose of this paper is to explore the developments which have precipitated the use and integration of geographical information systems (GIS) within the South African Police Services (SAPS).

The paper provides a historical overview of GIS within South Africa, supplemented with the legislative origins of the integration of GIS within policing in South Africa. Various spatial analytic operations that GIS technology affords are highlighted to illustrate the potential that the technology offers to law enforcement agencies in South Africa.

A number of challenges face the full integration of GIS within the day‐to‐day policing operations of the SAPS. Several critical success factors are identified which need to be eminently satisfied before the widespread integration of GIS within the SAPS can be achieved.

GIS is envisaged as a tool to benefit the criminal justice community by playing an important role in the policing and crime prevention process. This paper identifies the major inhibitors to the potential offered by GIS to supplement policing within a South African context.

With respect to the guiding “ideas” of Humboldt and their consequences for the constitution of science, describes the transition to a modern research university with the emergence of theory‐based practice, science‐based technology and technology‐based industry. The pure research imperative is endangered or even substituted by a new technological imperative

The object of this research is the reconstruction of the existing legal response by European Union states to the phenomenon of immigration. It seeks to analyse the process of conferral of protection.

One main dimension is selected and discussed: the case law of the national courts. The study focuses on the legal status of immigrants resulting from the intervention of these national courts.

The research shows that although the courts have conferred an increasing protection on immigrants, this has not challenged the fundamental principle of the sovereignty of the states to decide, according to their discretionary prerogatives, which immigrants are allowed to enter and stay in their territories. Notwithstanding the differences in the general constitutional and legal structures, the research also shows that the courts of the three countries considered – France, Germany and Spain – have progressively moved towards converging solutions in protecting immigrants.

The research contributes to a better understanding of the different legal orders analysed.

The purpose of this paper is to investigate the face-to-face citizen service encounter in public administrations’ front offices, and present a novel qualification approach to empower service personnel on-the-job, and thereby deepen the knowledge on the role of information and communication technology for advancing governmental reforms.

The presented study follows a design science research methodology, conducted in collaboration with the public administration of a major German city. Data were collected using multiple quantitative and qualitative methods, including questionnaires, semi-structured interviews and video analysis.

A novel on-the-job qualification approach for empowering public employees in their job-related skills, building on the concept of affordances, is developed. Thereto, six design principles for equipping artifacts with counseling affordances are presented. Evaluations in real-world environments provide first evidence that “learning with counseling affordances” constitutes an effective qualification measure to initiate experiential learning on-the-job, helping employees in the resource-restricted work environment of public front offices to obtain the skills to provide superior advisory services.

The “learning with counseling affordances” approach was developed in collaboration with an individual major German city and the paper provides first evidence of its effectiveness and suitability. Hence, the study’s insights should be approved by further research to strengthen generalizability.

The paper highlights the previously neglected aspects of employee’s skills and qualification for promoting governmental transformation. By highlighting the beneficial relationship between affordances and on-the-job learning, the paper provides novel insights on the role of information and communication technology to promote governmental transformation.

The influence of buoyancy forces on oscillatory Marangoni flow in liquid bridges of different aspect ratio is investigated by three‐dimensional, time‐dependent numerical solutions and by laboratory experiments using a microscale apparatus and a thermographic visualisation system. Liquid bridges heated from above and from below are investigated. The numerical and experimental results show that for each aspect ratio and for both the heating conditions the onset of the Marangoni oscillatory flow is characterized by the appearance of a standing wave regime; after a certain time, a second transition to a travelling wave regime occurs. The three‐dimensional flow organization at the onset of instability is different according to whether the bridge is heated from above or from below. When the liquid bridge is heated from below, the critical Marangoni number is larger, the critical wave number (m) is smaller and the standing wave regime is more stable, compared with the case of the bridge heated from above. For the critical azimuthal wave number, two correlation laws are found as a function of the geometrical aspect ratio A.