19,085 research outputs found
Policy Analysis for Natural Hazards: Some Cautionary Lessons From Environmental Policy Analysis
How should agencies and legislatures evaluate possible policies to mitigate the impacts of earthquakes, floods, hurricanes and other natural hazards? In particular, should governmental bodies adopt the sorts of policy-analytic and risk assessment techniques that are widely used in the area of environmental hazards (chemical toxins and radiation)? Environmental hazards policy analysis regularly employs proxy tests, in particular tests of technological feasibility, rather than focusing on a policy\u27s impact on well-being. When human welfare does enter the analysis, particular aspects of well-being, such as health and safety, are often given priority over others. Individual risk tests and other features of environmental policy analysis sometimes make policy choice fairly insensitive to the size of the exposed population. Seemingly arbitrary numerical cutoffs, such as the one-in-one million incremental risk level, help structure policy evaluation. Risk assessment techniques are often deterministic rather than probabilistic, and in estimating point values often rely on conservative rather than central-tendency estimates. The Article argues that these sorts of features of environmental policy analysis may be justifiable, but only on institutional grounds-if they sufficiently reduce decision costs or bureaucratic error or shirking-and should not be reflexively adopted by natural hazards policymakers. Absent persuasive. institutional justification, natural hazards policy analysis should be welfare-focused, multidimensional, and sensitive to population size, and natural hazards risk assessment techniques should provide information suitable for policy-analytic techniques of this sort
Trials with Microwave Detection of Vulnerable Road Users and Preliminary Empirical Modal Test. DRIVE Project V1031 Deliverable 11.
The general objective of the project is to provide a set of tools for the creation of traffic systems that enhance the safety and mobility of vulnerable road users (VRUs). This is being achieved in two ways: 1. By evaluating a number of RTI applications in signalling and junction control, in order to ascertain what benefits can be obtained for vulnerable road users by such local measures. 2. By developing a model of the traffic system that incorporates vulnerable road users as an integral part. The present workpackage, one of the last ones within the project, is intended to link the two strands together. The workpackage consists of two main parts: 1. Experiments with pedestrians and bicyclists. Two experiments were carried out, one in England (Bradford) and one in Sweden (Vijrjo), both applying microwave detectors for detection of pedestrians in a signalized intersection, but applying the detection in different ways. An observational study was carried out in Groningen (the Netherlands) to analyze bicycle/car interactions at an intersection with a cycle path. The aim of the experiment was to test the usefulness of a system giving car drivers warning in situations when a bicyclist approaches an intersection on a parallel bicycle path. 2. Reliability and validity testing of the submodels of the VRU-oriented traffic model WLCAN
The opportunistic replacement and inspection problem for components with a stochastic life time
The problem of finding efficient maintenance and inspection schemes in the case of components with a stochastic life time is studied and a mixed integer programming solution is proposed. The problem is compared with the two simpler problems of which the studied problem is a generalisation: The opportunistic replacement problem, assuming components with a deterministic life time and The opportunistic replacement problem for components with a stochastic life time, for maintenance schemes without inspections
Extended transition rates and lifetimes in Al I and Al II from systematic multiconfiguration calculations
Multiconfiguration Dirac-Hartree-Fock (MCDHF) and relativistic configuration
interaction (RCI) calculations were performed for 28 and 78 states in neutral
and singly ionized aluminium, respectively. In Al I, the configurations of
interest are for with to , as well as and
for . In Al II, the studied configurations are, besides the
ground configuration , with to and to , ,
, and . Valence and core-valence electron correlation
effects are systematically accounted for through large configuration state
function (CSF) expansions. Calculated excitation energies are found to be in
excellent agreement with experimental data from the NIST database. Lifetimes
and transition data for radiative electric dipole (E1) transitions are given
and compared with results from previous calculations and available
measurements, for both Al I and Al II. The computed lifetimes of Al I are in
very good agreement with the measured lifetimes in high-precision laser
spectroscopy experiments. The present calculations provide a substantial amount
of updated atomic data, including transition data in the infrared region. This
is particularly important since the new generation of telescopes are designed
for this region. There is a significant improvement in accuracy, in particular
for the more complex system of neutral Al I. The complete tables of transition
data are available
Implications of two-body fragment decay for the interpretation of emission chronology from velocity-gated correlation functions
From velocity-gated small-angle correlation functions the emission chronology
can be deduced for non-identical particles, if the emission is independent.
This is not the case for non-identical particles that originate from two-body
decay of fragments. Experimental results may contain contributions from both
independent emission and two-body decay, so care is needed in interpreting the
velocity-gated correlation functions. It is shown that in some special cases,
it is still possible to deduce the emission chronology, even if there is a
contribution from two-body decay.Comment: 15 pages, 4 figure
Condition based maintenance of trains doors
As part of the project DUST financed by Vinnova, we have investigated whether event data generated on trains can be used for finding evidence of wear on train doors. We have compared the event data and maintenance reports relating to doors of Regina trains. Although some interesting relations were found, the overall result is that the information
in event data about wear of doors is very limited
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