An experimental program for the investigation of panel instabilities caused by shock waves

Experimental methods and apparatus for studying panel instabilities caused by shock wave

Experimental study of shock-panel coupling - Preliminary results

Shock-panel coupling effects of supersonic turbulent flow driven by impedance hea

Historical roots of Agile methods: where did “Agile thinking” come from?

The appearance of Agile methods has been the most noticeable change to software process thinking in the last fifteen years [16], but in fact many of the “Agile ideas” have been around since 70’s or even before. Many studies and reviews have been conducted about Agile methods which ascribe their emergence as a reaction against traditional methods. In this paper, we argue that although Agile methods are new as a whole, they have strong roots in the history of software engineering. In addition to the iterative and incremental approaches that have been in use since 1957 [21], people who criticised the traditional methods suggested alternative approaches which were actually Agile ideas such as the response to change, customer involvement, and working software over documentation. The authors of this paper believe that education about the history of Agile thinking will help to develop better understanding as well as promoting the use of Agile methods. We therefore present and discuss the reasons behind the development and introduction of Agile methods, as a reaction to traditional methods, as a result of people's experience, and in particular focusing on reusing ideas from histor

Evaluation of acoustic testing techniques for spacecraft systems

External acoustic environments, structural responses, noise reductions, and the internal acoustic environments have been predicted for a typical shroud/spacecraft system during lift-off and various critical stages of flight. Spacecraft responses caused by energy transmission from the shroud via mechanical and acoustic paths have been compared and the importance of the mechanical path has been evaluated. Theoretical predictions have been compared extensively with available laboratory and in-flight measurements. Equivalent laboratory acoustic fields for simulation of shroud response during the various phases of flight have been derived and compared in detail. Techniques for varying the time-space correlations of laboratory acoustic fields have been examined, together with methods for varying the time and spatial distribution of acoustic amplitudes. Possible acoustic testing configurations for shroud/spacecraft systems have been suggested and trade-off considerations have been reviewed. The problem of simulating the acoustic environments versus simulating the structural responses has been considered and techniques for testing without the shroud installed have been discussed

Acoustic fatigue and sound transmission characteristics of a ram composite panel design

An experimental study to determine the acoustic fatigue characteristics of a flat multi-layered structural panel is described. The test panel represented a proposed design for the outer skin of a research application module to be housed within the space shuttle orbiter vehicle. The test specimen was mounted in one wall of the Wyle 100,000 cu ft reverberation room and exposed to a broadband acoustic environment having an overall level of 145 db. The test panel was exposed to nine separate applications of the acoustic environment, each application consisting of 250 seconds duration. Upon completion of the ninth test run, the specimen was exposed to a simulated micrometeoroid impact near the panel center. One additional test run of 250 seconds duration was then performed to complete the overall simulation of 50 flight missions. The experimental results show that no significant fatigue damage occurred until the test specimen was exposed to a simulated micrometeoroid impact. The intermediate foam layer forming the core of the test specimen suffered considerable damage due to this impact, causing a marked variation in the dynamic characteristics of the overall test panel. During the final application of the acoustic environment, the strain and acceleration response spectra showed considerable variation from those spectra obtained prior to impact of the panel. Fatigue damage from acoustic loading however, was limited to partial de-bonding around the edges of the composite panel

Through the Looking Glass: The Use of Lenses as an Interface Tool for Augmented Reality

Stephen N. Spencer The University of Washington Program Chairs Alan Chalmers Hock Soon Seah Publisher ACM Press New York, NY, US

Virulence of malaria is associated with differential expression of Plasmodium falciparum var gene subgroups in a case-control study

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a major pathogenicity factor in falciparum malaria that mediates cytoadherence. PfEMP1 is encoded by approximately 60 var genes per haploid genome. Most var genes are grouped into 3 subgroups: A, B, and C. Evidence is emerging that the specific expression of these subgroups has clinical significance. Using field samples from children from Papua New Guinea with severe, mild, and asymptomatic malaria, we compared proportions of transcripts of var groups, as determined by quantitative polymerase chain reaction. We found a significantly higher proportion of var group B transcripts in children with clinical malaria (mild and severe), whereas a large proportion of var group C transcripts was found in asymptomatic children. These data from naturally infected children clearly show that major differences exist in var gene expression between parasites causing clinical disease and those causing asymptomatic infections. Furthermore, parasites forming rosettes showed a significant up-regulation of var group A transcripts

Gender, war and militarism: making and questioning the links

The gender dynamics of militarism have traditionally been seen as straightforward, given the cultural mythologies of warfare and the disciplining of ‘masculinity’ that occurs in the training and use of men's capacity for violence in the armed services. However, women's relation to both war and peace has been varied and complex. It is women who have often been most prominent in working for peace, although there are no necessary links between women and opposition to militarism. In addition, more women than ever are serving in many of today's armies, with feminists rather uncertain on how to relate to this phenomenon. In this article, I explore some of the complexities of applying gender analyses to militarism and peace work in sites of conflict today, looking most closely at the Israeli feminist group, New Profile, and their insistence upon the costs of the militarized nature of Israeli society. They expose the very permeable boundaries between the military and civil society, as violence seeps into the fears and practices of everyday life in Israel. I place their work in the context of broader feminist analysis offered by researchers such as Cynthia Enloe and Cynthia Cockburn, who have for decades been writing about the ‘masculinist’ postures and practices of warfare, as well as the situation of women caught up in them. Finally, I suggest that rethinking the gendered nature of warfare must also encompass the costs of war to men, whose fundamental vulnerability to psychological abuse and physical injury is often downplayed, whether in mainstream accounts of warfare or in more specific gender analysis. Feminists need to pay careful attention to masculinity and its fragmentations in addressing the topic of gender, war and militarism

Discontinuous high-order finite-volume/finite-element method for inviscid compressible flows

The discontinuous, hybrid control-volume/finite-element method merges the desirable conservative properties and intuitive physical formulation of the finite-volume technique, with the capability of local arbitrary high-order accuracy distinctive of the discontinuous finite-element method. This relatively novel scheme has been previously applied to the solution of advection-diffusion problems and the shallow-water equations, and is in the present work extended to the Euler equations. The derivation of the method is presented in the general multi-dimensional case, and selected numerical problems are solved in the one- and two-dimensional case

Tourism and final wish making: the discourse of terminal illness and travel

This paper identifies a new discourse about tourism, that of final wish making. The website communications of charitable foundations whose dedicated purpose is to grant final wishes for adults with a terminal illness and their families were examined using critical discourse analysis. Specifically, the aim of this study was to understand how these charitable organisations construct, communicate and mediate meanings around terminal illness and travel for these individuals. Our study found that, promoted as a final wish in one’s life, tourism is framed as a transformational concept that is beneficial in the imminent time before death, as a legacy for life, and after death. Our analysis indicated implications around the memory-making potential of tourism and the differential power relations between final wish organisers and vulnerable individuals with a terminal illness. The paper calls for further research exploring the marginalisation of the terminally ill through tourism, but equally the potential of tourism to include the most vulnerable tourists in their final days