860 research outputs found
Experimental determination of the roughness functions of marine coatings
The aim of this paper is to determine the roughness functions of different marine coatings, including two novel FOUL-X-SPEL paints and two existing commercial coatings, and two control surfaces, using the overall method of Granville (1987). An extensive series of towing tests of flat plates coated with different antifouling coatings was carried out at the Kelvin Hydrodynamics Laboratory (KHL) of the University of Strathclyde. The tests were designed to examine the as applied drag performances of FOUL-X-SPEL paints and compare them with two existing reference paints and two control surfaces. The surface roughness amplitude parameters of all of the test surfaces were measured using a hull roughness analyser. In total over 150 runs were carried out, including a series of repeat tests designed to quantify the uncertainty in the results. The drag coefficients and roughness function values of each surface were evaluated along with the uncertainty limits
Technical Design Report for PANDA Electromagnetic Calorimeter (EMC)
This document presents the technical layout and the envisaged performance of the Electromagnetic Calorimeter (EMC) for the
PANDA target spectrometer. The EMC has been designed to meet the physics goals of the PANDA experiment. The performance figures are based on extensive prototype tests and radiation hardness studies. The document shows that the EMC is ready for construction up to the front-end electronics interface
Technical Design Report for the PANDA Solenoid and Dipole Spectrometer Magnets
This document is the Technical Design Report covering the two large spectrometer magnets of the PANDA detector set-up. It
shows the conceptual design of the magnets and their anticipated performance. It precedes the tender and procurement of the magnets and, hence, is subject to possible
modifications arising during this process
Physics Performance Report for PANDA Strong Interaction Studies with Antiprotons
To study fundamental questions of hadron and nuclear physics in interactions of antiprotons with nucleons and nuclei, the universal PANDA detector will be build. Gluonic excitations, the physics of strange and charm quarks and nucleon structure studies will be performed with unprecedented accuracy thereby allowing high-precision tests of the strong interaction. The proposed PANDA detector is a state-of-the-art internal target detector at the HESR at FAIR allowing the detection and identifcation of neutral and charged particles generated within the relevant angular and energy range. This report presents a summary of the physics accessible at PANDA and what performance can be expected
Sepsis carries a high mortality among hospitalised adults in Malawi in the era of antiretroviral therapy scale-up: A longitudinal cohort study
Objective: To assess mortality risk among adults presenting to an African teaching hospital with sepsis and severe sepsis in a setting of high HIV prevalence and widespread ART uptake. Methods: Prospective cohort study of adults (age ≥16 years) admitted with clinical suspicion of severe infection between November 2008 and January 2009 to Queen Elizabeth Central Hospital, a 1250-bed government-funded hospital in Blantyre, Malawi. Demographic, clinical and laboratory information, including blood and cerebrospinal fluid cultures were obtained on admission. Results: Data from 213 patients (181 with sepsis and 32 with severe sepsis; M:F = 2:3) were analysed. 161 (75.6%) patients were HIV-positive. Overall mortality was 22%, rising to 50% amongst patients with severe sepsis. The mortality of all sepsis patients commenced on antiretroviral therapy (ART) within 90 days was 11/28 (39.3%) compared with 7/42 (16.7%) among all sepsis patients on ART for greater than 90 days (p = 0.050). Independent associations with death were hypoxia (OR = 2.4; 95% CI, 1.1-5.1) and systolic hypotension (OR 7.0; 95% CI: 2.4-20.4). Conclusions: Sepsis and severe sepsis carry high mortality among hospitalised adults in Malawi. Measures to reduce this, including early identification and targeted intervention in high-risk patients, especially HIV-positive individuals recently commenced on ART, are urgently required
Performance optimisation of a flywheel energy storage system using the PNDC power hardware in the loop platform
The UK MOD has an objective to improve the efficiency and flexibility associated with the integration of naval electrical systems into both new & existing platforms. A more specific challenge for the MOD is in the de-risking of the integration of future pulse & stochastic loads such as Laser Directed Energy Weapons. To address this the Power Networks Demonstration Centre (PNDC) naval research programme is focused towards understanding & resolving the associated future power system requirements. To address these challenges, the UK MOD and the PNDC have worked collaboratively to develop a 540kVA Power Hardware in the Loop (PHIL) testing facility. For the UK MOD this supports the “UK-US Advanced Electric Power and Propulsion Project Arrangement (AEP3).” This testing facility has been used to explore the capabilities of PHIL testing and evaluate a Flywheel Energy Storage System (FESS) in a notional ship power system environment. This testing provided an opportunity to develop and further validate the capability of the PHIL platform for continued marine power system research. This paper presents on the results from PHIL testing of the FESS at PNDC, which involved both characterisation and interfacing the FESS within a simulated ship power system. The characterisation tests involved evaluating the: response to step changes in current reference; frequency and impedance characteristics; and response during uncontrolled discharge. The ship power system testing involved interfacing the FESS to a simulated real time notional ship power system model and evaluating the response of the FESS and the impact on the ship power system under a range of different operational scenarios. This paper also discuss the links between FESS characterisation testing and the development of the energy management system implemented in the real time model. This control system was developed to schedule operation of the FESS state (charging, discharging and idle) with the other simulated generation sources (the active front end and battery storage) and with the loads within the ship power system model. Finally, this paper highlights how the testing at PNDC has also supported the comparison and validation of previous FESS testing at Florida State University’s Centre Advanced Power Systems (FSU CAPS) facility, and how the combined efforts help to collectively de-risk future load Total Ship Integration and Evolving Intelligent Platforms in both UK and US programmes via the AEP3 PA
A new measurement of the neutron detection efficiency for the NaI Crystal Ball detector
We report on a measurement of the neutron detection efficiency in NaI
crystals in the Crystal Ball detector obtained from a study of single p0
photoproduction on deuterium using the tagged photon beam at the Mainz
Microtron. The results were obtained up to a neutron energy of 400 MeV. They
are compared to previous measurements made more than 15 years ago at the pion
beam at the BNL AGS
Structural phase transitions in the kagome lattice based materials Cs2-xRbxSnCu3F12 (x = 0, 0.5, 1.0, 1.5)
The solid solution Cs2-xRbxSnCu3F12 (x = 0, 0.5, 1.0, 1.5) has been
investigated crystallographically between 100 and 300 K using synchrotron X-ray
powder diffraction and, in the case of x = 0, neutron powder diffraction.Comment: 14 pages, 9 figure
Measurement of the transverse target and beam-target asymmetries in meson photoproduction at MAMI
We present new data for the transverse target asymmetry T and the very first
data for the beam-target asymmetry F in the
reaction up to a center-of-mass energy of W=1.9 GeV. The data were obtained
with the Crystal-Ball/TAPS detector setup at the Glasgow tagged photon facility
of the Mainz Microtron MAMI. All existing model predictions fail to reproduce
the new data indicating a significant impact on our understanding of the
underlying dynamics of meson photoproduction. The peculiar nodal
structure observed in existing T data close to threshold is not confirmed.Comment: 5 pages, 3 figures, accepted for publication in PR
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