Short-time Fourier transform laser Doppler holography

We report a demonstration of laser Doppler holography at a sustained acquisition rate of 250 Hz on a 1 Megapixel complementary metal-oxide-semiconductor (CMOS) sensor array and image display at 10 Hz frame rate. The holograms are optically acquired in off-axis configuration, with a frequency-shifted reference beam. Wide-field imaging of optical fluctuations in a 250 Hz frequency band is achieved by turning time-domain samplings to the dual domain via short-time temporal Fourier transformation. The measurement band can be positioned freely within the low radio-frequency spectrum by tuning the frequency of the reference beam in real-time. Video-rate image rendering is achieved by streamline image processing with commodity computer graphics hardware. This experimental scheme is validated by a non-contact vibrometry experiment

An (unintentional) façade of democratic debate

A review of the Colombian peace process. The article considers the actual extent of debate in a series of meetings and conferences in the UK that were held to analyse the peace process. The argument is put forward that the illegality, and thereby absence, of FARC at these meetings has contributed towards a distortion of events and arguments. Furthermore, it has left the current Colombian administration appearing as a far more inclusive and democratic institution than might be the case. The article welcomes the the interaction of the Colombian government in these UK meetings but suggests that measures are taken: i) to prevent the marginalization of FARC from democratic debate; ii) to limit the potential to breach Human Rights by the Colombian state; and iii) to define the difference between political violence and violent criminality

Browser-based Analysis of Web Framework Applications

Although web applications evolved to mature solutions providing sophisticated user experience, they also became complex for the same reason. Complexity primarily affects the server-side generation of dynamic pages as they are aggregated from multiple sources and as there are lots of possible processing paths depending on parameters. Browser-based tests are an adequate instrument to detect errors within generated web pages considering the server-side process and path complexity a black box. However, these tests do not detect the cause of an error which has to be located manually instead. This paper proposes to generate metadata on the paths and parts involved during server-side processing to facilitate backtracking origins of detected errors at development time. While there are several possible points of interest to observe for backtracking, this paper focuses user interface components of web frameworks.Comment: In Proceedings TAV-WEB 2010, arXiv:1009.330

Locality and information transfer in quantum operations

We investigate the situation in which no information can be transferred from a quantum system B to a quantum system A, even though both interact with a common system C

Internet Advertising and the Generalized Second Price Auction: Selling Billions of Dollars Worth of Keywords

We investigate the "generalized second price" auction (GSP), a new mechanism which is used by search engines to sell online advertising that most Internet users encounter daily. GSP is tailored to its unique environment, and neither the mechanism nor the environment have previously been studied in the mechanism design literature. Although GSP looks similar to the Vickrey-Clarke-Groves (VCG) mechanism, its properties are very different. In particular, unlike the VCG mechanism, GSP generally does not have an equilibrium in dominant strategies, and truth-telling is not an equilibrium of GSP. To analyze the properties of GSP in a dynamic environment, we describe the generalized English auction that corresponds to the GSP and show that it has a unique equilibrium. This is an ex post equilibrium that results in the same payoffs to all players as the dominant strategy equilibrium of VCG.