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A reliability analysis of a solid oxide fuel cell (SOFC) system is presented for applications with strict constant power supply requirements, such as data centers. The purpose is to demonstrate the effect when moving from a module-level to a system-level in terms of reliability, also considering effects during start-up and degradation.

In-house experimental data on a system-level are used to capture the behavior during start-up and normal operation, including drifts of the operation point due to degradation. The system is assumed to allow replacement of stacks during operation, but a minimum number of stacks in operation is needed to avoid complete shutdown. Experimental data are used in conjunction with a physics-based performance model to construct the failure probability function. A dynamic program then solves the optimization problem in terms of time and replacement requirements to minimize the total negative deviation from a given target reliability.

Results show that multi-stack SOFC systems face challenges which are only revealed on a system- and not on a module-level. The main finding is that the reliability of multi-stack SOFC systems is not sufficient to serve as sole power source for critical applications such as data center.

The principal methodology may be applicable to other modular systems which include multiple critical components (of the same kind). These systems comprise other electrochemical systems such as further fuel cell types.

The novelty of this work is the combination of mathematical modeling to solve a real-world problem, rather than assuming idealized input which lead to more benign system conditions. Furthermore, the necessity to use a mathematical model, which captures sufficient physics of the SOFC system as well as stochasticity elements of its environment, is of critical importance. Some simplifications are, however, necessary because the use of a detailed model directly in the dynamic program would have led to a combinatorial explosion of the numerical solution space.

The legend of Porsche Chief Executive Peter Schutz pacing the pits at Le Mans with tears in his eyes after a motor racing success is very much the stuff corporate cultures are reared from.

Social theory contains contributions related to the processes of semiosis. Between the subjective experience of intentional meanings and objectivized structure of meanings there is a sphere of meaningful interactions and collective actions. Arguments are presented that it is possible to integrate symbolic interactionist orientation and Durkheimian tradition in the study of social symbolism in the perspective of collective action approach and pragmatism. That allows going beyond the cognitive limitations inherited from phenomenological view on symbolism as manifested in the concepts of P. Berger and T. Luckmann about the social construction of reality. A model for a multidimensional analysis of social symbolism and its functions is proposed.

To provide an informative and stimulating view of some key issues in interdepartmental conflict.

Based on the first study in the German‐speaking world, of the impact of interdepartmental conflict, in the period 2002‐2003, 300 enterprises participated. Respondents were at all levels of business hierarchy and all sizes of enterprise and ranged from junior manager to chairman and from the smallest firms to global market leaders.

Several conclusions: it is a common illusion that an enterprise is one big happy family. It is a mixture of groups and people with aims, perceptions and preferences which can easily and frequently conflict with one another. This is clearly a major and often underestimated source of stress, demotivation and inefficiency.

Demonstrates ways of using conflict productively. The first step is a self‐critical appraisal of one's own role in terms of interdepartmental cooperation. The next step of self‐reflection entails the reader coming to terms with any possible prejudices he/she may have towards other departments. These stereotypes form and colour behaviour at departmental interfaces and frequently become self‐fulfilling prophecies. A limitation of the study is that small firms with up to ten employees were not included.

The paper offers many new insights through the survey and primary research on which it is based. Also, the German experience is highly relevant to the UK and USA, while at the same time, providing some useful bases for cross‐cultural comparison.

The idea of “leadership” has occupied an important position in the study of management, so that text‐books on organisational behaviour routinely allocate a chapter to discussion about it. It is invariably handled by recourse to a review of the major schools of thought and empirical findings associated with the concept. More specifically, writers of such texts are typically concerned with those aspects of leadership studies which have focused on its possible linkage with various indicators of performance or effectiveness. In addressing such issues, such writers focus on whether it is possible to isolate the personal characteristics of the effective leader, and whether it is possible to discern effective leadership styles.

The concept of institution has been used by scholars from across a number of disciplines to explain a wide variety of phenomena. However, the philosophical roots of this concept have not been well examined, nor have implications for contemporary institutional analysis been fully appreciated. Returning to the works of Husserl and Merleau-Ponty reveals a depth of thinking that has otherwise been overlooked by institutional theorists. In particular, the author’s analysis reveals two critical insights. First, whereas organizational scholars have closely linked the concepts of institution and taken-for-grantedness, these two concepts were originally understood to be phenomenologically distinct. Second, a detailed examination of Merleau-Ponty’s later work poses the concept of flesh – the twining of the visible and the invisible – as the basis for the interplay of institutions. In turn, the idea of flesh as the foundation of institution invites a more radical reimagining of the growing bifurcation between microfoundations and macrofoundations.

This paper discusses Frank H. Knight's thought under three major themes, namely subjectivism, interpretation and social economics. Knight's economics starts with a conscious mind construct which is able to infer under partial knowledge. Conscious human action is purposive, forward looking and extends towards other individuals. Rejecting neoclassical positivism, Knight points to the need for economics to reconceptualize itself as an interpretative study, a methodology in the Weberian tradition. Furthermore, his allure for phenomenological economics opens a methodological possibility for the Austrian School of Economics. This paper concludes that Knight's insight earns himself a place in the history of subjectivist economics.