Reasoning with uncertain points, straight lines, and straight line segments

Decisions based on basic geometric entities can only be optimal, if their uncertainty is propagated trough the entire reasoning chain. This concerns the construction of new entities from given ones, the testing of geometric relations between geometric entities, and the parameter estimation of geometric entities based on spatial relations which have been found to hold. Basic feature extraction procedures often provide measures of uncertainty. These uncertainties should be incorporated into the representation of geometric entities permitting statistical testing, eliminates the necessity of specifying non-interpretable thresholds and enables statistically optimal parameter estimation. Using the calculus of homogeneous coordinates the power of algebraic projective geometry can be exploited in these steps of image analysis. This review collects, discusses and evaluates the various representations of uncertain Preprint submitted to Elsevier 23 July 2009geometric entities in 2D together with their conversions. The representations are extended to achieve a consistent set of representations allowing geometric reasoning. The statistical testing of geometric relations is presented. Furthermore, a generic estimation procedure is provided for multiple uncertain geometric entities based on possibly correlated observed geometric entities and geometric constraints. Key words: spatial reasoning, uncertainty, homogeneous coordinates, geometric entitie

Observation of double radiative capture on pionic hydrogen

We report the first observation of double radiative capture on pionic hydrogen. The experiment was conducted at the TRIUMF cyclotron using the RMC spectrometer, and detected $\gamma$--ray coincidences following $\pi^-$ stops in liquid hydrogen. We found the branching ratio for double radiative capture to be $(3.05 \pm 0.27(stat.) \pm 0.31(syst.)) \times 10^{-5}$. The measured branching ratio and angle-energy distributions support the theoretical prediction of a dominant contribution from the $\pi \pi \to \gamma \gamma$ annihilation mechanism.Comment: 4 Pages, 4 Figures. accepted for publication in Phys. Rev. Let

Radiative Muon Capture on Hydrogen and the Induced Pseudoscalar Coupling

The first measurement of the elementary process $\mu^- p \rightarrow \nu_{\mu} n \gamma$ is reported. A photon pair spectrometer was used to measure the partial branching ratio ($2.10 \pm 0.22) \times 10^{-8}$ for photons of k > 60 MeV. The value of the weak pseudoscalar coupling constant determined from the partial branching ratio is $g_p(q^{2}=-0.88m_{\mu}^2) = (9.8 \pm 0.7 \pm 0.3) \cdot g_a(0)$, where the first error is the quadrature sum of statistical and systematic uncertainties and the second error is due to the uncertainty in $\lambda_{op}$, the decay rate of the ortho to para $p \mu p$ molecule. This value of g_p is $\sim$1.5 times the prediction of PCAC and pion-pole dominance.Comment: 13 pages, RevTeX type, 3 figures (encapsulated postscript), submitted to Phys. Rev. Let

Prediction of photoperiodic regulators from quantitative gene circuit models

Photoperiod sensors allow physiological adaptation to the changing seasons. The external coincidence hypothesis postulates that a light-responsive regulator is modulated by a circadian rhythm. Sufficient data are available to test this quantitatively in plants, though not yet in animals. In Arabidopsis, the clock-regulated genes CONSTANS (CO) and FLAVIN, KELCH, F-BOX (FKF1) and their lightsensitive proteins are thought to form an external coincidence sensor. We use 40 timeseries of molecular data to model the integration of light and timing information by CO, its target gene FLOWERING LOCUS T (FT), and the circadian clock. Among other predictions, the models show that FKF1 activates FT. We demonstrate experimentally that this effect is independent of the known activation of CO by FKF1, thus we locate a major, novel controller of photoperiodism. External coincidence is part of a complex photoperiod sensor: modelling makes this complexity explicit and may thus contribute to crop improvement

Environmental SLAPPs in the UK: threat or opportunity?

Strategic lawsuits against public participation (SLAPPs) brought against the environmental movement in the UK since the 1990s are examined. SLAPPs, a form of Green backlash, have been mobilised across a wide range of policy areas that have seen vigorous campaigning and protest by the movement, including roads, GMOs and, more recently, climate change. SLAPPs are typically regarded as a threat, designed to close down democratic free speech and protest. However, in the UK, there are some notable cases where the environmental movement has been able to use agency to convert what may appear as a legal threat into a positive legal or media opportunity

A new measurement of the properties of the rare decay K -> pi+ e+ e-

A large low-background sample of events (10300) has been collected for the rare decay of kaons in flight K+ -> pi+ e+ e- by experiment E865 at the Brookhaven AGS. The decay products were accepted by a broad band high-resolution charged particle spectrometer with particle identification. The branching ratio (2.94 +- 0.05(stat.) +- 0.13(syst.) +- 0.05(model))*10**{-7} was determined normalizing to events from the decay chain K+ -> pi+ pi0; pi0 -> e+ e- gamma. From the analysis of the decay distributions the vector nature of this decay is firmly established now, and limits on scalar and tensor contributions are deduced. From the (e+ e-) invariant mass distribution the decay form factor f(z)=f0(1+ delta*z) (z=M(ee)**2/m(K)**2) is determined with delta=2.14 +- 0.13 +- 0.15. Chiral QCD perturbation theory predictions for the form factor are also tested, and terms beyond leading order O(p**4) are found to be important.Comment: 4 pages, 5 figure

Non-Parametric Sequential Frame Decimation for Scene Reconstruction in Low-Memory Streaming Environments

Abstract not provide

Does the engineering culture in UK higher education advance women’s careers?

Current research suggests that increases in the number of women studying engineering and related courses have not been matched by a similar increase in women engineering professionals. This suggests that although women are attracted to engineering, their experiences in higher education (HE) discourage them from pursuing their chosen career path. The paper explores whether the masculine culture of the engineering sector permeates the culture and curriculum in engineering HE, and if it does, what impact this has on women engineering students. This is achieved through semi-structured, qualitative interviews with a range of female engineering students from both the pre and post 1992 university sectors. Findings indicate that while women are not deterred from pursuing their chosen engineering career, the culture and structure of the engineering education system has been designed for a male audience. This suggests that engineering HE does not benefit most female students to the same extent as male students. It is recommended that HE engineering must review its structure, culture, practices and curriculum if it is to retain female engineering graduates and to attract more women into the sector. This paper fulfils an identified gap in research on women in engineering and will be of interest to university engineering departments and faculties and the Engineering Council, as well as to those in the fields of social policy, education and equal opportunities

Induced pseudoscalar coupling of the proton weak interaction

The induced pseudoscalar coupling $g_p$ is the least well known of the weak coupling constants of the proton's charged--current interaction. Its size is dictated by chiral symmetry arguments, and its measurement represents an important test of quantum chromodynamics at low energies. During the past decade a large body of new data relevant to the coupling $g_p$ has been accumulated. This data includes measurements of radiative and non radiative muon capture on targets ranging from hydrogen and few--nucleon systems to complex nuclei. Herein the authors review the theoretical underpinnings of $g_p$, the experimental studies of $g_p$, and the procedures and uncertainties in extracting the coupling from data. Current puzzles are highlighted and future opportunities are discussed.Comment: 58 pages, Latex, Revtex4, prepared for Reviews of Modern Physic

Corporate social responsibility: The good, the bad and the ugly

In this article I critically analyze contemporary discourses of corporate social responsibility and related discourses of sustainability and corporate citizenship. I argue that despite their emancipatory rhetoric, discourses of corporate citizenship, social responsibility and sustainability are defined by narrow business interests and serve to curtail interests of external stakeholders. I provide an alternate perspective, one that views discourses of corporate citizenship, corporate social responsibility, and sustainability as ideological movements that are intended to legitimize and consolidate the power of large corporations. I also problematize the popular notion of organizational 'stakeholders'. I argue that stakeholder theory of the firm represents a form of stakeholder colonialism that serves to regulate the behavior of stakeholders. I conclude by discussing implications for critical management studies