A new earthquake catalogue for Bulgaria and the conterminous Balkan high hazard region

A new homogenous earthquake catalogue covering Bulgaria and the surrounding Balkan area has been created with intention of performing a consistent seismic hazard assessment across the region. In keeping with modern requirements of cataloguing seismicity, this catalogue has been made homogenous as far as possible with regards to magnitude, which has been provided on any of four different reported scales for each event; mb, Ms, Mw and ML. A key historical catalogue for the region has been used to represent the early instrumental period of earthquake recording (1900 to 1963), whilst data have been obtained from the International Seismological Centre (ISC), National Earthquake Information Center (NEIC) and National Observatory of Athens (NOA) to cover the instrumental period of earthquake recording (1964 to 2004). ISC data have also been used to develop a new mb→Ms magnitude conversion equation for the catalogued region. Application of this new magnitude conversion relation, in combination with other selected magnitude scale correlations, ensures reported magnitudes can be systematically rendered onto homogenized Ms and Mw scales for all earthquakes. This catalogue contains 3681 events with homogenized magnitudes ≥4.0 Mw, for the time interval 1900 to 2004 (inclusive), located in the region bounded by 39°–45° N, 19°–29° E, at focal depths of 0.0 km to 401.0 km and in a magnitude range 4.0≤Mw≤7.2. Selected large magnitude (M≥6.0 Ms) earthquakes have had their reported magnitudes reassessed – and adjusted if necessary – in light of work by other authors. Applied statistical approaches aimed at determining the lower threshold to magnitude completeness suggest this catalogue is complete down to a homogenized surface-wave magnitude of 4.6 Ms

Directional drilling attitude control with input disturbances and feedback delay

This paper presents a general approach for the attitude control of directional drilling tools for the oil and gas industry. It extends the recent work where a kinematic bilinear model of the directional drilling tool was developed and used as the basis for Constant Build Rate (CBR) controller design. The CBR controller in combination with a modified Smith Predictor (SP) is implemented for the attitude control of the directional drilling. The results of a transient simulation of the proposed modified SP-CBR controller are presented and compared with that from the CBR controller of the earlier studies. It is shown that the modified SP-CBR controller significantly reduces the adverse effects of input disturbances and time delay on the feedback measurements with respect to stability and performance

Bilinear modelling and bilinear PI control of directional drilling

This paper presents the design of an inclination- and azimuth-hold controllers and their subsequent stability and performance analysis for directional drilling tools as typically used in the oil industry. Using an input transformation developed in earlier work that partially linearizes and decouples the plant dynamics of the directional drilling tool, a bilinear model of the directional drilling tool is developed and is used as the basis for Bilinear PI controller design. Results for a transient simulation of the proposed BPI controller are presented and compared with that of the PI controller of the earlier work. It is presented that BPI controller gives more consistent responses over a broader operating range compared to the PI controller. In addition, the effect of time delay on the feedback measurements with respect to the stability and performance is investigated in the simulations

The Magellan Evolution of Galaxies Spectroscopic and Ultraviolet Reference Atlas (MEGaSaURA) I: The Sample and the Spectra

We introduce Project MEGaSaURA: The Magellan Evolution of Galaxies Spectroscopic and Ultraviolet Reference Atlas. MEGaSaURA comprises medium-resolution, rest-frame ultraviolet spectroscopy of N=15 bright gravitationally lensed galaxies at redshifts of 1.68$<$z$<$3.6, obtained with the MagE spectrograph on the Magellan telescopes. The spectra cover the observed-frame wavelength range $3200 < \lambda_o < 8280$ \AA ; the average spectral resolving power is R=3300. The median spectrum has a signal-to-noise ratio of $SNR=21$ per resolution element at 5000 \AA . As such, the MEGaSaURA spectra have superior signal-to-noise-ratio and wavelength coverage compared to what COS/HST provides for starburst galaxies in the local universe. This paper describes the sample, the observations, and the data reduction. We compare the measured redshifts for the stars, the ionized gas as traced by nebular lines, and the neutral gas as traced by absorption lines; we find the expected bulk outflow of the neutral gas, and no systemic offset between the redshifts measured from nebular lines and the redshifts measured from the stellar continuum. We provide the MEGaSaURA spectra to the astronomical community through a data release.Comment: Resubmitted to AAS Journals. Data release will accompany journal publication. v2 addresses minor comments from refere

The effect of an emollient containing urea, ceramide NP, and lactate on skin barrier structure and function in older people with dry skin

Xerosis affects up to 75% of older people and develops as a result of a skin barrier defect. Emollients are widely used to treat xerosis; however, there is limited understanding of the differences between them and their effects on the skin barrier in older people. This study aimed to compare the effect of a commercially available emollient containing 5% urea, ceramide NP and lactate (test emollient) to an alternative emollient without these additives (control emollient) on the properties of the skin barrier in older people. Two cohorts of 21 volunteers aged 60+ years with dry skin were recruited. The first applied the test emollient to one forearm and no treatment to the other for 28-days. The second compared the test emollient to the control emollient observing the same parameters. Effects on the skin barrier were determined by measuring skin barrier function, hydration, skin surface pH and by analyzing FTIR spectra before and after treatment. A third cohort of 6 young adults was recruited to investigate the effect of a single treatment with the test emollient on the molecular structure of the skin barrier at greater depths by employing the tape-stripping technique. The test emollient hydrated the skin to a significantly greater extent and for a longer period of time compared to the control emollient, an effect associated with a significant elevation of carboxylate groups (a marker of NMF content) within the stratum corneum. Furthermore, the test emollient imparted additional benefits to the structure and function of the skin barrier not exhibited by the control emollient. In conclusion the test emollient addressed the pathological features of xerotic aged skin, supporting its use as first-line therapy for xerotic skin conditions in this population

Integrating security solutions to support nanoCMOS electronics research

The UK Engineering and Physical Sciences Research Council (EPSRC) funded Meeting the Design Challenges of nanoCMOS Electronics (nanoCMOS) is developing a research infrastructure for collaborative electronics research across multiple institutions in the UK with especially strong industrial and commercial involvement. Unlike other domains, the electronics industry is driven by the necessity of protecting the intellectual property of the data, designs and software associated with next generation electronics devices and therefore requires fine-grained security. Similarly, the project also demands seamless access to large scale high performance compute resources for atomic scale device simulations and the capability to manage the hundreds of thousands of files and the metadata associated with these simulations. Within this context, the project has explored a wide range of authentication and authorization infrastructures facilitating compute resource access and providing fine-grained security over numerous distributed file stores and files. We conclude that no single security solution meets the needs of the project. This paper describes the experiences of applying X.509-based certificates and public key infrastructures, VOMS, PERMIS, Kerberos and the Internet2 Shibboleth technologies for nanoCMOS security. We outline how we are integrating these solutions to provide a complete end-end security framework meeting the demands of the nanoCMOS electronics domain

A Finite Element Computation of the Gravitational Radiation emitted by a Point-like object orbiting a Non-rotating Black Hole

The description of extreme-mass-ratio binary systems in the inspiral phase is a challenging problem in gravitational wave physics with significant relevance for the space interferometer LISA. The main difficulty lies in the evaluation of the effects of the small body's gravitational field on itself. To that end, an accurate computation of the perturbations produced by the small body with respect the background geometry of the large object, a massive black hole, is required. In this paper we present a new computational approach based on Finite Element Methods to solve the master equations describing perturbations of non-rotating black holes due to an orbiting point-like object. The numerical computations are carried out in the time domain by using evolution algorithms for wave-type equations. We show the accuracy of the method by comparing our calculations with previous results in the literature. Finally, we discuss the relevance of this method for achieving accurate descriptions of extreme-mass-ratio binaries.Comment: RevTeX 4. 18 pages, 8 figure

Spatially Resolved Outflows in a Seyfert Galaxy at z = 2.39

We present the first spatially resolved analysis of rest-frame optical and UV imaging and spectroscopy for a lensed galaxy at z = 2.39 hosting a Seyfert active galactic nucleus (AGN). Proximity to a natural guide star has enabled high signal-to-noise VLT SINFONI + adaptive optics observations of rest-frame optical diagnostic emission lines, which exhibit an underlying broad component with FWHM ~ 700 km/s in both the Balmer and forbidden lines. Measured line ratios place the outflow robustly in the region of the ionization diagnostic diagrams associated with AGN. This unique opportunity - combining gravitational lensing, AO guiding, redshift, and AGN activity - allows for a magnified view of two main tracers of the physical conditions and structure of the interstellar medium in a star-forming galaxy hosting a weak AGN at cosmic noon. By analyzing the spatial extent and morphology of the Ly-alpha and dust-corrected H-alpha emission, disentangling the effects of star formation and AGN ionization on each tracer, and comparing the AGN induced mass outflow rate to the host star formation rate, we find that the AGN does not significantly impact the star formation within its host galaxy.Comment: 16 pages, 5 figures, accepted for publication in Ap