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A new method of studying the accelerated ageing of interconnection materials is applied to a high‐stability thick film resistor system (the Du Pont HS‐80 system). The new method, referred to hereafter as the in‐situ method, allows measurement of the electrical resistance of a thick film resistor to a resolution of a few ppm during accelerated ageing. With the in‐situ technique, the electrical resistance measurements are performed at the elevated ageing temperature during the ageing treatment, whereas with the conventional ageing method the resistance measurements are carried out at room temperature, between subsequent annealing steps. The measuring resolution obtainable with the in‐situ method is orders of magnitude better than with the conventional method. The ageing kinetics can therefore be studied on a shorter time scale and in greater detail than with the conventional method. In this paper, the authors use the in‐situ method to study the accelerated ageing of the Du Pont HS‐80 thick film resistor system, encapsulated with a proper glaze. It will be shown that kinetics of the resistance drift observed in this system cannot be described by an Arrhenius‐type equation. The ageing data can only be interpreted in terms of a kinetic model incorporating a spectrum of activation energies for the ageing process. Such a model is given, and is shown to provide a good explanation of the observed ageing behaviour. The physical process that causes the observed ageing is most probably diffusion of silver from the contacting terminals into the amorphous matrix of the thick film resistor.

In this paper, it is shown that the so‐called in‐situ electrical measurement technique is a valuable tool for understanding failure mechanisms in thick film dielectrics. The technique makes it possible to measure important electrical characteristics of thick film dielectric systems in the temperature range from room temperature up to 900°C. This information is essential to understand failure mechanisms and to optimise the system with respect to quality and reliability. Mainly two electrical properties have been investigated: (i) the electrical resistance of the dielectric as a function of temperature and (ii) the spontaneous electromotive force occurring at higher temperatures between two metal layers with the dielectric in between. A significant result of the work is the observation of a close correlation between the leakage current measured through the dielectric at elevated temperatures, and the ability of the dielectric to resist shorting and blistering effects during the preparation of circuits. Secondly, from in‐situ voltage measurements, it was confirmed that the mixed metallurgy system Au(bottom)‐dielectric‐Ag(top) acts at 850°C as a spontaneous battery, and the battery voltage (i.e., the spontaneous electromotive force) was measured. Depending on the type of dielectric, a battery voltage up to 200 mV between the two metal layers was observed. As a result of this spontaneous electromotive force, blistering occurs. The battery voltage was shown to be much smaller in unmixed metallurgy systems with Ag(bottom)‐dielectric‐Ag(top) or Au(bottom)‐dielectric‐Au(top). However, if an external voltage of 300 mV is applied to such a system during a temperature profile up to 850°C, blisters can also be induced. This shows unambiguously that blistering is a voltage driven effect.

ISHM invites papers for the above Conference, to be held on 29–31 May 1991 in Rotterdam, The Netherlands. Papers should cover areas such as: design, manufacturing, packaging and interconnection, materials and processing, applications, reliability, components, new technologies, marketing and economics, optoelectronics. Summaries should be in English, length 200–300 words. The deadline for receipt of summaries is 30 September 1990. (For full details, see announcement on pp. 54–55.)

The purpose of this paper is to investigate oil-gas slug formation in horizontal straight pipe and its associated pressure gradient, slug liquid holdup and slug frequency.

The abrupt change in gas/liquid velocities, which causes transition of flow patterns, was analyzed using incompressible volume of fluid method to capture the dynamic gas-liquid interface. The validity of present model and its methodology was validated using Baker’s flow regime chart for 3.15 inches diameter horizontal pipe and with existing experimental data to ensure its correctness.

The present paper proposes simplified correlations for liquid holdup and slug frequency by comparison with numerous existing models. The paper also identified correlations that can be used in operational oil and gas industry and several outlier models that may not be applicable.

The correlation may be limited to the range of material properties used in this paper.

Numerically derived liquid holdup and holdup frequency agreed reasonably with the experimentally derived correlations.

The models could be used to design pipeline and piping systems for oil and gas production.

The paper simulated all the seven flow regimes with superior results compared to existing methodology. New correlations derived numerically are compared to published experimental correlations to understand the difference between models.

This paper examines data protection related ex ante transaction costs borne by the private sector in the context of smart city service (SCS) public tendering in the European Union after the introduction of the General Data Protection Regulation. This study aims to establish the determinants of ex ante transaction costs related to data protection as well as to determine their relevance toward (tender) competition.

A statistical analysis of a survey sample of 72 SCS tender bids.

The potential of relationship management to foster more private sector investment in data protection for SCSs is established, i.e. stronger ties between parties lead to higher private sector investment. Furthermore, it is found that investing more in data protection can further boost both internal capabilities and the organizational reputation of tendering organizations. Finally, the analysis exposes a potential problem concerning the market for data protection originating from the dominant approach concerning SCS tender bid evaluation.

SCS tender bid evaluation is not perceived by the evaluated companies as having data protection as a (core) component. As a consequence, there is no strong competition in that specific area. To induce the private sector to structurally develop SCSs that can be expected to safeguard the fundamental rights of citizens, a more thorough evaluation of data protection aspects of bids imposes itself. Such an overhaul is likely to demand additional public sector resources and expertise.

This paper constitutes an early investigation into data protection related ex ante transaction costs borne by private sector actors. Incentives for data protection investment in the context of public procurement procedures are discussed.

It has often been said that a great part of the strength of Aslib lies in the fact that it brings together those whose experience has been gained in many widely differing fields but who have a common interest in the means by which information may be collected and disseminated to the greatest advantage. Lists of its members have, therefore, a more than ordinary value since they present, in miniature, a cross‐section of institutions and individuals who share this special interest.

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).

The implementation of public–private partnerships (PPPs), particularly in low- and middle-income countries, has been hampered by external stakeholders’ opposition leading to the failure of several projects. The purpose of this paper is to develop a framework to improve external stakeholder management in PPP projects.

Two case studies consisting of 23 interviews with a wide range of internal and external stakeholders were employed. This was supplemented with a focus group approach to validate the framework.

A new framework for the management of external stakeholders is developed. It encompasses new features such as the dynamic identification of stakeholders at each project phase and their corresponding interests.

The scope is road transportation projects in Nigeria and thus the recommendations may not be globally applicable.

The findings can help the public sector and their agencies to manage external stakeholders and maintain successful relationships on PPP projects.

The paper contributes to existing knowledge in four key areas: it confirms that the skill and actions of internal stakeholders are vital to the stakeholder management process; it shows that one-off stakeholder identification proposed in literature is a flawed approach; it proposes that the identification of external stakeholders’ interests be dynamic; and it adds the perspective of low- and middle-income countries in stakeholder management in PPP projects.

Public-private partnerships (PPPs) have become integral in delivering public services and infrastructure, particularly in the context of megaprojects. This paper focuses on the interplay between stakeholder management, challenges, critical success factors (CSFs), and the overall success of PPP-arranged civil infrastructure megaprojects.

Using the PRISMA methodology, we comprehensively analyze challenges and critical success factors (CSFs) influencing stakeholder engagement within PPP megaprojects. A focused search equation identified 595 papers, which were distilled down to 34 relevant papers and case studies. Qualitative analysis of these papers revealed 48 CSFs categorized into 11 challenges from a stakeholder management perspective, which were further delineated across public, private, and combined sectors, and then mapped along the PPP megaproject lifecycle.

Informed by a diverse amalgam of civil and project management literature, this research reveals the intricate dynamics of PPP megaprojects across the globe that emphasize the critical nature of stakeholder engagement, analysis, and management practices. Key findings highlighted conflicting interests between public and private stakeholders, manifesting in challenges like project performance versus profitability. The literature emphasized instances where neglect of local community culture led to adverse social outcomes. A universal conclusion underscored the context-specific nature of challenges and CSFs, stressing the need for a holistic understanding of stakeholders and project dynamics.

The paper acknowledges that it focused on 34 selected papers out of 595 identified. This sample focuses on civil engineering megaprojects which may not fully represent the breadth of research in the field, potentially missing out on valuable insights from excluded studies.

We believe that the compiled list of CSFs, organized according to stakeholder relationships and the project lifecycle, serves as a potent tool for managers and planners. By enabling the identification of complexity from diverse perspectives, this research allows elucidating the challenges faced by the management team in PPP megaproject.

This research identifies several social outcomes related to PPP megaprojects. Critical Success Factors identified as such should allow the project managers to maximize benefits for society and minimize risk and negative externalities.

This study contributes valuable insights for policies and practices by systematically describing challenges and related CSFs throughout the PPP megaproject lifecycle. Additionally, it addresses the nuanced aspects of internal and external stakeholder management, thereby contributing to the overall understanding and best practices required to confront complex megaprojects involving a wide range of stakeholder groups.

This paper focusses on external stakeholders’ perspective of stakeholder management in public–private partnerships (PPP) projects within the context of developing countries where public opposition to PPP projects is prevalent. The purpose of this paper is to identify the key enablers to PPP projects’ success from the perspective of external stakeholders.

Data were collected from two case studies via semi-structured interviews in two PPP project locations in Nigeria. In total, 14 external stakeholders comprising community leaders, trade unionists and human right activist participated in the research.

Five key enablers of external stakeholder management were identified. These are as follows: the choice of project location; transparency of the internal stakeholders; timing of stakeholder engagement; knowledge of PPP; and relationship with internal stakeholders.

External stakeholders’ perspective of stakeholder management in PPP projects within the context of developing countries new to PPP has been established. The practical implications of the five enablers can be used by policy makers and industry professionals to ensure effective stakeholder management of PPP projects.