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How do engineers inspect the inside of a nuclear reactor? Laser scanning can turn it into a normal television picture.

This paper aims at exploring the dynamics of multiple identities of women entrepreneurs (WE). The paper analyse how WE do identity work in relation to specific identity regulations in the particular French cultural context. The objective is to understand how the entrepreneurial identity process of women is built through both confrontation and synergy with other social identities.

The paper opted for a qualitative and abductive methodological design. In total, 41 French WE from diverse business activities were interviewed. The empirical material was subject to thematic analysis.

The findings reveal the ability of these WE to deal with numerous and various identities. Their daily strategies to accommodate different roles depict how their entrepreneurial activity is intertwined with their personal and social life. The paper are far away from the picture of a monolithic entrepreneur without social dimensions. Given that, the findings broaden the too simplistic vision of WE as an homogeneous whole. Within this group of French WE, the analysis reveals that forms of identity work are along a continuum from accepting conventional norms and social expectations and integrating them in self-identity, or challenging them by accommodation or transformation, or, in turn, by redefining and proposing new norms. It also brings a nuanced understanding of complexity and multidimensionality of their daily life.

Finally by studying French WE, the paper identify new practices, new interactions between social roles which could be also relevant for men. In fact, the study challenges the traditional framework on entrepreneurship, which produces an incomplete view of entrepreneurs, by omitting historical and social variables. This disembodied vision of entrepreneur could not be applied to women and probably could not be applied to contemporaneous men either.

This study aims to better understand the emotional challenges that inexperienced accounting researchers may face in conducting ethnographies. To do so, the authors use Arlie Russell Hochschild’s (1979, 1983) notions of “feeling rules” and “emotion work” to shed light on the possible nature and impact of these challenges, and how her ideas may also become fruitful for academic purposes.

The authors take a reflective approach in sharing the raw observation notes and research diaries as first-time ethnographers in the area of management accounting. The authors use these to analyze “unprocessed” experiences of emotional challenges from the fieldwork and how the authors learned to cope with them.

The authors illustrate how emotional challenges in conducting ethnographies can be rooted in a clash with prevalent feeling rules of certain study situations. The authors explore the conditions under which these clashes occur and how they may prompt researchers to respond through means of emotion work to (re-)stabilize those situations. Based on these insights, the authors also discuss how wider conventions of the accounting academy may contribute to emotional challenges as they stand in contrast to principles of ethnographic research.

There remains a tendency in the accounting domain to largely omit emotional challenges in the making of ethnographies, especially in writing up studies. In this paper, the authors are motivated to break this silence and openly embrace such challenges as an asset when the authors talk about the process of creating knowledge.

Nacre is a biological material constituting the innermost layer of the shells of gastropods and bivalves. It consists of polygonal tablets of aragonite, tessellated to form individual layers and having the adjacent layers as well as the tablets within a layer bonded by a biopolymer. Due to its highly complex hierarchical microstructure, nacre possesses an outstanding combination of mechanical properties, the properties which are far superior to the ones that are predicted using techniques such as the rule of mixtures. Given these properties, a composite armor the structure of which mimics that of nacre may have improved performance over a monolithic armor having a similar composition and an identical areal density. The paper aims to discuss these issues.

In the present work, an attempt is made to model a nacre-like composite armor consisting of B₄C tablets and polyurea tablet/tablet interfaces. The armor is next tested with respect to impact by a solid right circular cylindrical (SRCC) rigid projectile, using a transient non-linear dynamics finite-element analysis. The ballistic-impact response and the penetration resistance of the armor are then compared with that of the B₄C monolithic armor having an identical areal density. Furthermore, the effect of various nacre microstructural features (e.g. surface profiling, micron-scale asperities, mineral bridges between the overlapping tablets lying in adjacent layers, and B₄C nano-crystallinity) on the ballistic-penetration resistance of the composite armor is investigated in order to identify an optimal nacre-like composite armor architecture having the largest penetration resistance.

The results obtained clearly show that a nacre-like armor possesses a superior penetration resistance relative to its monolithic counterpart, and that the nacre microstructural features considered play a critical role in the armor-penetration resistance.

The present work indicates that for a given choice of armor material, penetration resistance may be improved by choosing a structure resembling that of nacre.

The purpose of this paper is to model a nacre-like composite material, consisting of tablets and polyurea tablet/tablet interfaces, B₄C. This composite material is being considered in the construction of the so-called backing-plate, a layer within a multi-functional/multi-layer armor system.

Considering the basic functions of the backing-plate (i.e. to provide structural support for the ceramic-strike-face and to stop a high-velocity projectile and the accompanying fragments) in such an armor system, the composite-material architecture is optimized with respect to simultaneously achieving high flexural stiffness and high ballistic-penetration resistance. Flexural stiffness and penetration resistance, for a given architecture of the nacre-like composite material, are assessed using a series of transient non-linear dynamics finite-element analyses. The suitability of the optimized composite material for use in backing-plate applications is then evaluated by comparing its performance against that of the rolled homogeneous armor (RHA), a common choice for the backing-plate material.

The results obtained established: a trade-off between the requirements for a high flexural stiffness and a high ballistic-penetration resistance in the nacre-like composite material; and overall superiority of the subject composite material over the RHA when used in the construction of the backing-plate within multi-functional/multi-layer armor systems.

This study extends the authors previous research on nacre-mimetic armor to optimize the architecture of the armor with respect to its flexural stiffness and ballistic-penetration resistance, so that these properties could be increased over the levels attained in the current choice (RHA) for the backing layer of multi-functional/multi-layer armor.

A parallel finite‐element/multi‐body‐dynamics investigation is carried out of the effect of up‐armoring on the off‐road performance of a prototypical high‐mobility multipurpose‐wheeled vehicle (HMMWV). The paper seeks to investigate the up‐armoring effect on the vehicle performance under the following off‐road maneuvers: straight‐line flatland braking; straight‐line off‐angle downhill braking; and sharp left turn.

For each of the above‐mentioned maneuvers, the appropriate vehicle‐performance criteria are identified and the parameters used to quantify these criteria are defined and assessed. The ability of a computationally efficient multi‐body dynamics approach when combined with a detailed model for tire/soil interactions to yield results qualitatively and quantitatively consistent with their computational counterparts obtained using computationally quite costly finite element analyses is assessed.

The computational results obtained clearly reveal the compromises in vehicle off‐road performance caused by the up‐armoring employ to improve vehicle blast and ballistic protection performance/survivability. The results obtained are also analyzed and explained in terms of general field‐test observations in order to judge physical soundness and fidelity of the present computational approaches.

The paper offers insights into the effects of up‐armoring of the HMMWV on off‐road vehicle performance.

Fiber-reinforced armor-grade polymer-matrix composite materials with a superior penetration resistance are traditionally developed using legacy knowledge and trial-and-error empiricism. This approach is generally quite costly and time-consuming and, hence, new (faster and more economical) approaches are needed for the development of high-performance armor-grade composite materials. One of these new approaches is the so-called materials-by-design approach. Within this approach, extensive use is made of the computer-aided engineering (CAE) analyses and of the empirically/theoretically established functional relationships between an armor-grade composite-protected structure, the properties of the composite materials, material microstructure (as characterized at different length-scales) and the material/structure synthesis and fabrication processes. The paper aims to discuss these issues.

In the present work, a first step is made toward applying the materials-by-design approach to the development of the armor-grade composite materials and protective structures with superior ballistic-penetration resistance. Specifically, CAE analyses are utilized to establish functional relationships between the attributes/properties of the composite material and the penetration resistance of the associated protective structure, and to identify the combination of these properties which maximize the penetration resistance. In a follow-up paper, the materials-by-design approach will be extended to answer the questions such as what microstructural features the material must possess in order for the penetration resistance to be maximized and how such materials should be synthesized/processed.

The results obtained show that proper adjustment of the material properties results in significant improvements in the protective structure penetration resistance.

To the authors’ knowledge, the present work is the first reported attempt to apply the materials-by-design approach to armor-grade composite materials in order to help improve their ballistic-penetration resistance.

Traditionally, an armor-grade composite is based on a two-dimensional (2D) architecture of its fiber reinforcements. However, various experimental investigations have shown that armor-grade composites based on 2D-reinforcement architectures tend to display inferior through-the-thickness mechanical properties, compromising their ballistic performance. To overcome this problem, armor-grade composites based on three-dimensional (3D) fiber-reinforcement architectures have recently been investigated experimentally. The paper aims to discuss these issues.

In the present work, continuum-level material models are derived, parameterized and validated for armor-grade composite materials, having four (two 2D and two 3D) prototypical reinforcement architectures based on oriented ultra-high molecular-weight polyethylene fibers. To properly and accurately account for the effect of the reinforcement architecture, the appropriate unit cells (within which the constituent materials and their morphologies are represented explicitly) are constructed and subjected to a series of virtual mechanical tests (VMTs). The results obtained are used within a post-processing analysis to derive and parameterize the corresponding homogenized-material models. One of these models (specifically, the one for 0°/90° cross-collimated fiber architecture) was directly validated by comparing its predictions with the experimental counterparts. The other models are validated by examining their physical soundness and details of their predictions. Lastly, the models are integrated as user-material subroutines, and linked with a commercial finite-element package, in order to carry out a transient non-linear dynamics analysis of ballistic transverse impact of armor-grade composite-material panels with different reinforcement architectures.

The results obtained clearly revealed the role the reinforcement architecture plays in the overall ballistic limit of the armor panel, as well as in its structural and damage/failure response.

To the authors’ knowledge, the present work is the first reported attempt to assess, computationally, the utility and effectiveness of 3D fiber-reinforcement architectures for ballistic-impact applications.