121 research outputs found

    Working platforms for cranes – review of design approaches and recommendations for a safe design

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    peer reviewedThis paper provides a technical insight into the essential aspects to be considered in the proper design of a safe working platform for heavy construction machinery. Considering the complexity of the operational boundary conditions, the uncertainties of the ground characteristics and the variability of the loads applied by the construction machinery, a clear understanding of the possible failure modes and the definition of a criterion for the design of countermeasures seems to be essential in this application. This can be better achieved by considering the significant increase in cost and time delays associated with the failure of the working platforms. This paper discusses various possible failure mechanisms in the working platforms and examines the advantages of using geosynthetic reinforcing elements to avoid the risk of failure

    Ethical Decision Making and Leadership Stress

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    The theme of this entry is how ethical decisionmaking is influenced by leadership stress. From a traditional point of view, stress is seen as a potential threat to leaders’ ethical decisions (Selart and Johansen 2011). There is substantial evidence suggesting that stress has a negative impact on leaders’ cognition and information processing, leading to errors and biases in their decisionmaking. However, it must be pointed out that in many types of professions (e.g., chief pilots, chief surgeons, and chief fire officers) leaders are more or less bound to develop advanced levels of stresstolerance in order to function ethically. This implies that stress does not always have to result in unethical decisions among leaders (Klein 1996). The structure of this entry is organized such that its first part is devoted to clarification of the relationship between ethical decision-making and leadership, while the second part is focused on how stress adds to this relationship

    Numerical investigation of geogrid back-anchored sheet pile walls

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    peer reviewedIn the last decades, geosynthetic reinforcement has been widely used in geotech-nical applications. Recently, geogrid has also been used to back-anchor sheet pile walls. However, this system has not received sufficient attention neither in research nor in construction. Due to the complex interactions between soil, geogrid and sheet pile wall, the applicability of common design guidelines for conventionally back-anchored walls to this particular system has to be proven. To develop a fundamental understanding about the influence of various components of the system on its behaviour, numerical investigations have been conducted within this study. In this paper the influence of geogrid inclination, design of geogrid-sheet pile connection including prestressing and geogrid position on the earth pressure distribution and wall deformation is discussed. The numerical results revealed that the position of geogrid and design of geogrid-sheet pile connection significantly affect the earth pressure distribution. The wall deformations are mainly influenced by the geogrid position

    Reversing the Extraverted Leadership Advantage: The Role of Employee Proactivity

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    Extraversion predicts leadership emergence and effectiveness, but do groups perform more effectively under extraverted leadership? Drawing on dominance complementarity theory, we propose that although extraverted leadership enhances group performance when employees are passive, this effect reverses when employees are proactive, because extraverted leaders are less receptive to proactivity. In Study 1, pizza stores with leaders rated high (low) in extraversion achieved higher profits when employees were passive (proactive). Study 2 constructively replicates these findings in the laboratory: passive (proactive) groups achieved higher performance when leaders acted high (low) in extraversion. We discuss theoretical and practical implications for leadership and proactivity

    From Interactions to Institutions: Microprocesses of Framing and Mechanisms for the Structuring of Institutional Fields

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    Despite the centrality of meaning to institutionalization, little attention has been paid to how meanings evolve and amplify to become institutionalized cultural conventions. We develop an interactional framing perspective to explain the microprocesses and mechanisms by which this occurs. We identify three amplification processes and three ways frames stack up or laminate that become the building blocks for diffusion and institutionalization of meanings within organizations and fields. Although we focus on “bottom-up” dynamics, we argue that framing occurs in a politicized social context and is inherently bidirectional, in line with structuration, because microlevel interactions instantiate macrostructures. We consider how our approach complements other theories of meaning making, its utility for informing related theoretical streams, and its implications for organizing at the meso and macro levels

    Individuals responses to economic cycles: Organizational relevance and a multilevel theoretical integration

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    Toward a Unified Framework of Perceived Negative Leader Behaviors Insights from French and British Educational Sectors

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    In this paper, we challenge the commonly held assumption that actors in the education sector are largely ethical, and that there is therefore little need to scrutinize leader behaviors in this sector. We also overcome past scholars’ tendencies to either focus selectively on positive leader behaviors, or to stay content with categorizing leader behaviors into effective and ineffective (if at all they do focus on negative leader behaviors). Using data (Critical Incidents) from three case studies previously conducted in eight British and French academic establishments, we show that not only do negative leader behaviors abound in the education sector, but they can also be differentiated into three types: (1) behaviors emanating from leaders’ lack of functional skills i.e., ineffective behaviors, (2) behaviors emanating from leaders’ insouciance toward harming the organization and its members i.e., dysfunctional behaviors, and (3) behaviors emanating from leaders’ lack of honesty, integrity, ethicality, and transparency i.e., unauthentic behaviors. We enrich current understanding on ineffective, dysfunctional, and unauthentic leader behaviors, and offer a unified (yet differentiated) framework of negative leader behaviors in the academic sector. Since each type of negative behavior emanates from different motivational drivers, different measures are required to curb them. These are also discussed. A comparison of our findings with those from leadership studies in other sectors reveals that negative leader behaviors in the education sector are quite similar to those in other sectors
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