Introducing Performativity to Crisis Management Theory: An Illustration from the 2003 French Heat Wave Crisis Response

While current crisis management literature focuses on the necessity of consistent data and shared interpretation to coordinate effectively, contrastingly, this paper highlights the predominating influence of crisis responders' performances on information transmission. Based on an exploratory interpretive analysis of the 2003 French heat wave crisis response, our findings reveal that performances can support immediate reaction and involvement, but can also generate conflicts or misunderstandings that may burden coordination. This work's contribution to the crisis management literature is in threefold. First, we enrich the crisis management literature by proposing performativity as a potential analytical lens for collective action during crisis response. Second, we propose some practical recommendations to improve crisis management training through the application of the concept of performativity. Finally, we propose a critical perspective on tacitly held assumptions in crisis management.     

GD&T-Based Characterization of Short-Range Non-contact 3D Imaging Systems

We present a series of test metrics, artifacts, and procedures for characterizing and verifying the operating limits of a short-range non-contact three-dimensional imaging system. These metrics have been designed to correspond to dimensioning and tolerancing metrics that are widely used in industry (e.g. automotive, aerospace, etc.). We introduce operating limit metrics that correspond with the geometric dimensioning and tolerancing (GD&T) metrics of Form (Flatness and Circularity), Orientation (Angularity), Location (Sphere, Corner, and Hole Position Errors), and Size (Diameter, Sphere-spacing, Plane-spacing and Angle Errors). An example is presented to illustrate how these metrics, artifacts, and associated test procedures can be used in practice.     

Public-Private Cooperation in Infrastructure Development: A Principal-Agent Story of Contingent Liabilities, Fiscal Risks, and Other (Un)pleasant Surprises

With increasing pressure on physical infrastructure and limited resources, most governments have turned to various forms of collaboration with the private sector to help finance, build, and/or operate public assets. While the benefits of such joint efforts are potentially numerous, they also entail major risks that are hard to assess adequately. This paper discusses the economic and financial rationale, including risks, for partnerships between the public and the private sectors as a way to share the burden of developing infrastructure. It also proposes a principal-agent framework to help conceptualize the relations between the government and the private firm in public-private partnerships (PPPs).     

Bayesian assessment of the characteristic concrete compressive strength using combined vague-informative priors

Bayesian statistics can be used in order to determine the characteristic value of an unknown distribution based on a limited number of test samples. In cases where no previous test results are available, most often a Bayesian method based on vague prior information is used. The assumption of a vague or uniform prior results in a conservative approach in cases where only a limited number of test results are available. However, in case of concrete, prior information on concrete strength can be found in literature or country-specific prior information can be determined. Therefore, the use of a combined vague-informative prior is of particular interest, more specifically in the form of scaled inverse-χ² distributions that can be used for updating the standard deviation of the strength distribution of concrete. The differences between the use of a vague and a combined vague-informative prior are investigated through Monte Carlo simulations. Because prior information is taken into account, the uncertainty regarding the standard deviation of the predictive strength distribution is significantly reduced.     

The development of an environmental friendly catalytic system for the conversion of olefins

An elegant method is described for the synthesis of ZSM-22. By controlled addition of seeds and applying stirring during the crystallization, the phase purity and the crystal size can be controlled. The H-ZSM-22 is tested in the dense phase oligomerization of propene at 180–250°C and 70 bar. It is found that adding small amounts of water significantly increases the activity and decreases the deactivation of the catalyst. Secondly, it is shown that catalyst activity is higher after calcination at 400°C versus 550°C and that smaller crystal sizes positively affect the catalyst activity. Both observations are ascribed to the presence of active sites located near the zeolite outer surface accounting for a major part of the catalytic activity.     

Crosslinking of elastomers upon ageing: a kinetic approach based on crystallinity changes followed by DSC

It was observed that crosslinking reactions resulting both from peroxide decomposition or photoageing at wavelengths longer than 300 nm involve a drastic decrease of the crystallinity of some dienic elastomers, such as polybutadienes (rich in cis 1,4 and 1,2 microstructures) and polycyclo‐octene. By comparing precisely the rate of decomposition of dicumyl peroxide and that of the crystallinity decrease, it was possible to show that the kinetics of crystallinity loss observed upon ageing can be identified with that of the crosslinking of elastomers. The results indicate that the crosslinking process can be followed directly by DSC measurement of the crystallization/melting cycle. © 2003 Society of Chemical Industry     

Loisirs et santé mentale: les relations entre la motivation pour la pratique des loisirs et le bien-être psychologique.

Studied interactions between motivations for leisure activities and psychological well-being to test the hypothesis that a high degree of motivational self-determination is associated with a high level of psychological functioning. 463 secondary school students (mean age 17 yrs) completed a questionnaire assessing their intrinsic and extrinsic motivation for different types of leisure activities. The types of motivation differed with regard to their levels of self-determination. Results were analyzed in relation to questionnaire data on psychological well-being. The Motivation for Leisure Scale (L. G. Pelletier et al, 1994) and the Index of Psychological Well-Being (Pelletier et al) were used. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

SIFER: Scale-Invariant Feature Detector with Error Resilience

We present a new method to extract scale-invariant features from an image by using a Cosine Modulated Gaussian (CM-Gaussian) filter. Its balanced scale-space atom with minimal spread in scale and space leads to an outstanding scale-invariant feature detection quality, albeit at reduced planar rotational invariance. Both sharp and distributed features like corners and blobs are reliably detected, irrespective of various image artifacts and camera parameter variations, except for planar rotation. The CM-Gaussian filters are approximated with the sum of exponentials as a single, fixed-length filter and equal approximation error over all scales, providing constant-time, low-cost image filtering implementations. The approximation error of the corresponding digital signal processing is below the noise threshold. It is scalable with the filter order, providing many quality-complexity trade-off working points. We validate the efficiency of the proposed feature detection algorithm on image registration applications over a wide range of testbench conditions.     

Ultrafast Atomic Diffusion Paths in Fine-Grained Nickel Obtained by Spark Plasma Sintering

Metallurgical and Materials Transactions A - Short-circuit diffusion in fine-grained Ni samples processed by Spark Plasma sintering has been investigated by the radiotracer technique. Ni grain...