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The purpose of this paper is to determine the reason for the discrepancy in estimated and observed damage caused by fragmenting charges in closed environments.

A series of carefully conducted physical and numerical experiments was conducted. The results were analyzed and compared.

The analysis shows that for fragmenting charges in closed environments, dust plays a far larger role than previously thought, leading to much lower pressures and damage.

In light of these findings, many assumptions and results for fragmenting charges in closed environments need to be reconsidered.

This implies that for a far larger class of problems than previously estimated it is imperative to take into consideration dust production and its effect on the resulting pressures.

This is the first time such a finding has been reported in this context.

Prompted by the empirical evidence that achievable flow solver speeds for large problems are limited by what appears to be a time of the order of O(0.1) sec/timestep regardless of the number of cores used, the purpose of this paper is to identify why this phenomenon occurs.

A series of timing studies, as well as in-depth analysis of memory and inter-processors transfer requirements were carried out for a typical field solver. The results were analyzed and compared to the expected performance.

The analysis shows that at present flow speeds per core are already limited by the achievable transfer rate to RAM. For smaller domains/larger number of processors, the limiting speed of CFD solvers is given by the MPI communication network.

This implies that at present, there is a “limiting useful size” for domains, and that there is a lower limit for the time it takes to update a flowfield.

For practical calculations this implies that the time required for running large-scale problems will not decrease markedly once these applications migrate to machines with hundreds of thousands of cores.

This is the first time such a finding has been reported in this context.

This study aims to evaluate blast loads on and the response of submerged structures.

An arbitrary Lagrangian–Eulerian method is developed to model fluid–structure interaction (FSI) problems of close-in underwater explosions (UNDEX). The “fluid” part provides the loads for the structure considers air, water and high explosive materials. The spatial discretization for the fluid domain is performed with a second-order vertex-based finite volume scheme with a tangent of hyperbola interface capturing technique. The temporal discretization is based on explicit Runge–Kutta methods. The structure is described by a large-deformation Lagrangian formulation and discretized via finite elements. First, one-dimensional test cases are given to show that the numerical method is free of mesh movement effects. Thereafter, three-dimensional FSI problems of close-in UNDEX are studied. Finally, the computation of UNDEX near a ship compartment is performed.

The difference in the flow mechanisms between rigid targets and deforming targets is quantified and evaluated.

Cavitation is modeled only approximately and may require further refinement/modeling.

The results demonstrate that the proposed numerical method is accurate, robust and versatile for practical use.

Better design of naval infrastructure [such as bridges, ports, etc.].

To the best of the authors’ knowledge, this study has been conducted for the first time.

Tourism and hospitality employment have long faced widely recognised challenges with regard to employment, its workforce and the workplace environment, issues that have been addressed by generations of policymakers and practitioners without evident success or solution. These wicked problems are frequently characterised by inherent paradoxes and, therefore, accepting the tenets of paradox theory provides the basis for recognising the need to accept contradictions as a reality which a search for solutions will not resolve. This chapter presents six examples of wicked problems in tourism and hospitality employment, which are underpinned by paradoxes as proxies for the much wider range of intractable problems that beset policy-making and practice in this vital area of tourism and hospitality. The chapter concludes by suggesting ways in which wicked problems can be accommodated, and stakeholders can learn to understand and live with paradoxes.

Resource reconfiguration enables firms to adapt in dynamic environments by supplementing, removing, recombining, or redeploying resources. Whereas prior research has underscored the merits of resource reconfiguration and the modes for implementing it, little is known about the antecedents of this practice. According to prior research, under given industry conditions, resource reconfiguration is prompted by a firm’s corporate strategy and by characteristics of its knowledge assets. We complement this research by identifying learning from performance feedback as a fundamental driver of resource reconfiguration. We claim that performance decline relative to aspiration motivates the firm’s investment in knowledge reconfiguration, and that this investment is reinforced by the munificence of complementary resources in its industry, although uncertainty about the availability of such resources limits that investment. Testing our conjectures with a sample of 248 electronics firms during the period 1993–2001, we reveal a clear distinction between exploitative reconfiguration, which combines existing knowledge elements, and exploratory reconfiguration, which incorporates new knowledge elements. We demonstrate that performance decline relative to aspiration motivates a shift from exploitative reconfiguration to exploratory reconfiguration. Moreover, munificence of complementary resources mitigates the tradeoff between exploratory and exploitative reconfigurations, whereas uncertainty weakens the motivation to engage in both types of reconfiguration, despite the performance gap. Nevertheless, codeployment, which extends the deployment of knowledge assets to additional domains, is more susceptible to uncertainty than redeployment, which withdraws those assets from their original domain and reallocates them to new domains. Our study contributes to emerging research on resource reconfiguration, extends the literature on learning from performance feedback, and advances research on balancing exploration and exploitation.

Performance feedback can be constructed using firms’ own (historical) performance, or the performance of peers (social). Those two types of performance feedback can be consistent (both positive, both negative) or inconsistent (one positive, the other negative). The research on the impact of consistent versus inconsistent feedback has been inconclusive, suggesting that inconsistent feedback might lead to more intense or less intense responses, or no response. In this paper, we theorize and test how firms respond to (in)consistent performance feedback.

We test our hypotheses on a longitudinal sample of 2,819 private, high-growth firms in the US with 6,688 observations between the years 2007 and 2016. Our dataset comprises 25 different industries. We use topic modeling on textual data from firms’ web pages to capture portfolio expansion.

We find that consistent negative performance feedback strengthens portfolio expansion, but consistent positive feedback does not influence portfolio expansion. We also find that inconsistent performance feedback weakens portfolio expansion, but only with negative historical feedback and positive social feedback.

We contribute to the Behavioral Theory of the Firm by improving our understanding of mechanisms of feedback configurations. Specifically, we elaborate on the role of (in)consistent social feedback when firms respond to historical performance feedback. We also contribute to the theory by better understanding private firms’ responses to performance feedback.

Achieving continuous innovation performance still poses a major challenge to established companies as it requires high flexibility and adaptability in usually efficiently structured organisations. One way to tackle this challenge lies in establishing effective behaviours to successfully establish and apply innovation leadership mechanisms in an organisation. The emerging agile leadership style could provide such effective behaviours, as it addresses the demand for flexibility and adaptability on the organisational level. Despite these clear parallels research on the link between agile leadership and innovation leadership, and their possible combined contribution to drive continuous innovation performance is still in its infancy. Accordingly, the present study examines the behaviours of agile leaders to promote continuous innovation in established companies. It applies a discovery-driven research process of agile leaders to derive and categorise their behaviours. The subsequent comparison of the identified agile leadership behaviours with innovation leadership mechanisms from existing literature leads to eight specific, combined agile leadership principles within the three categories empowerment, performance enhancement, and support for continuous innovation. Eventually, this basis allows the conceptualisation of a first exploratory framework with the identified behaviours as possible enablers, and innovation leadership mechanisms as possible mediators for the continuous innovation performance, subject to test. These findings enhance existing theory by clarifying a possible link between agile leadership and continuous innovation. That way, practitioners can profit from concrete principles for agile leaders to inspire and enable continuous innovation in individuals and teams.

The overall goal of science is to build a valid and reliable body of knowledge about the functioning of the world and how applying that knowledge can change it. As personnel and human resources management researchers, we aim to contribute to the respective bodies of knowledge to provide both employers and employees with a workable foundation to help with those problems they are confronted with. However, what research on research has consistently demonstrated is that the scientific endeavor possesses existential issues including a substantial lack of (a) solid theory, (b) replicability, (c) reproducibility, (d) proper and generalizable samples, (e) sufficient quality control (i.e., peer review), (f) robust and trustworthy statistical results, (g) availability of research, and (h) sufficient practical implications. In this chapter, we first sing a song of sorrow regarding the current state of the social sciences in general and personnel and human resources management specifically. Then, we investigate potential grievances that might have led to it (i.e., questionable research practices, misplaced incentives), only to end with a verse of hope by outlining an avenue for betterment (i.e., open science and policy changes at multiple levels).