Delivery performance of conventional aircraft by terminal-area, time-based air traffic control: A real-time simulation evaluation

A description and results are presented of a study to measure the performance and reaction of airline flight crews, in a full workload DC-9 cockpit, flying in a real-time simulation of an air traffic control (ATC) concept called Traffic Intelligence for the Management of Efficient Runway-scheduling (TIMER). Experimental objectives were to verify earlier fast-time TIMER time-delivery precision results and obtain data for the validation or refinement of existing computer models of pilot/airborne performance. Experimental data indicated a runway threshold, interarrival-time-error standard deviation in the range of 10.4 to 14.1 seconds. Other real-time system performance parameters measured include approach speeds, response time to controller turn instructions, bank angles employed, and ATC controller message delivery-time errors

Planning for HUGO International yearbook

This report describes efforts expended in convening a planning committee to examine the ethical, legal, and social issues raised in genomic mapping

Mass Dependent Loss of Resolution in Radially Inhomogeneous ExB Ion Traps

ExB ion traps, such as Fourier transform Ion Cyclotron Resonance mass spectrometers (FY:ICR), mass analyze sample ions based on differences in their cyclotron frequencies in a homogeneous magnetic field. The high resolution mass measurements of FT-ICR are based on the relationship between the frequency of the cyclotron orbit and the mass-to-charge (m/q) ratio of an ion. Both the orbit and the frequency/mass relationship result from the radial forces on the ion. Ions trapped by inhomogeneous electric fields experience different magnitudes of the radial electric fields at different positions resulting in a positionally dependent frequency. Such differences in orbital frequencies for ions of a single m/q ratio result in line broadening and loss of resolution

Cross-Over between universality classes in a magnetically disordered metallic wire

In this article we present numerical results of conduction in a disordered quasi-1D wire in the possible presence of magnetic impurities. Our analysis leads us to the study of universal properties in different conduction regimes such as the localized and metallic ones. In particular, we analyse the cross-over between universality classes occurring when the strength of magnetic disorder is increased. For this purpose, we use a numerical Landauer approach, and derive the scattering matrix of the wire from electron's Green's function.Comment: Final version, accepted for publication in New Journ. of Physics, 27 pages, 28 figures. Replaces the earlier shorter preprint arXiv:0910.427

A new multi-gas constrained model of trace gas non-homogeneous transport in firn: evaluation and behaviour at eleven polar sites

Insoluble trace gases are trapped in polar ice at the firn-ice transition, at approximately 50 to 100 m below the surface, depending primarily on the site temperature and snow accumulation. Models of trace gas transport in polar firn are used to relate firn air and ice core records of trace gases to their atmospheric history. We propose a new model based on the following contributions. First, the firn air transport model is revised in a poromechanics framework with emphasis on the non-homogeneous properties and the treatment of gravitational settling. We then derive a nonlinear least square multi-gas optimisation scheme to calculate the effective firn diffusivity (automatic diffusivity tuning). The improvements gained by the multi-gas approach are investigated (up to ten gases for a single site are included in the optimisation process). We apply the model to four Arctic (Devon Island, NEEM, North GRIP, Summit) and seven Antarctic (DE08, Berkner Island, Siple Dome, Dronning Maud Land, South Pole, Dome C, Vostok) sites and calculate their respective depth-dependent diffusivity profiles. Among these different sites, a relationship is inferred between the snow accumulation rate and an increasing thickness of the lock-in zone defined from the isotopic composition of molecular nitrogen in firn air (denoted d15N). It is associated with a reduced diffusivity value and an increased ratio of advective to diffusive flux in deep firn, which is particularly important at high accumulation rate sites. This has implications for the understanding of d15N of N2 records in ice cores, in relation with past variations of the snow accumulation rate. As the snow accumulation rate is clearly a primary control on the thickness of the lock-in zone, our new approach that allows for the estimation of the lock-in zone width as a function of accumulation may lead to a better constraint on the age difference between the ice and entrapped gases

Spatial pattern and temporal evolution of glacial terminations of the last 800 ka

The second QUIGS workshop brought together 28 delegates to assess current knowledge and research needs on the spatio-temporal patterns of climate forcing, responses and feedbacks that characterize glacial terminations, i.e. transitions between glacial and interglacial periods

Life cycle sustainability assessment : a tool for exercising due diligence in life cycle management

Starting from the output ‘The Future We Want’ of the Rio+20 conference 2012, the main focus of this chapter is on social responsibility (SR) in the value chain. The historical context of SR is discussed, related to the international standards as are the Guidance on Social Responsibility and the Global Reporting Initiative, linked with the management of organizations and enterprises. It is emphasized that due diligence along the value chain is seen as a requirement for claiming ‘social responsibility’. Life cycle sustainability assessment (LCSA) contributes to the assessment and life cycle management (LCM) to the follow-up of exercising due diligence, all within the context of sustainable development. The over-arching LCSA is a combination of three different life cycle assessment techniques allowing to assess the impacts along the value chain: environmental LCA, social LCA and life cycle costing

Remanence effects in the electrical resistivity of spin glasses

We have measured the low temperature electrical resistivity of Ag : Mn mesoscopic spin glasses prepared by ion implantation with a concentration of 700 ppm. As expected, we observe a clear maximum in the resistivity (T ) at a temperature in good agreement with theoretical predictions. Moreover, we observe remanence effects at very weak magnetic fields for the resistivity below the freezing temperature Tsg: upon Field Cooling (fc), we observe clear deviations of (T ) as compared with the Zero Field Cooling (zfc); such deviations appear even for very small magnetic fields, typically in the Gauss range. This onset of remanence for very weak magnetic fields is reminiscent of the typical signature on magnetic susceptibility measurements of the spin glass transition for this generic glassy system

Interferometry with Photon-Subtracted Thermal Light

We propose and implement a quantum procedure for enhancing the sensitivity with which one can determine the phase shift experienced by a weak light beam possessing thermal statistics in passing through an interferometer. Our procedure entails subtracting exactly one (which can be generalized to m) photons from the light field exiting an interferometer containing a phase-shifting element in one of its arms. As a consequence of the process of photon subtraction, and somewhat surprisingly, the mean photon number and signal-to-noise ratio of the resulting light field are thereby increased, leading to enhanced interferometry. This method can be used to increase measurement sensitivity in a variety of practical applications, including that of forming the image of an object illuminated only by weak thermal light