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Development and application of an evaluation framework for urban traffic management and Intelligent Transport Systems
The aim of this paper is to present and apply a new evaluation framework for traffic management and Intelligent Transport Systems, to assist urban transport authorities in assessing relevant policies and technologies as to their performance. The principles behind performance measures and indices are outlined, along with a description of theframework development methodology. Two Key Performance Indicators (KPIs) for the topics of mobility and traffic accidents respectively are formulated and operative definitions are presented. Then, the new KPIs are applied to a case study in the city of Paris, involving the introduction of a scheme granting priority to buses at signalised junctions. The results from the before- and after-analysis are reported and interpreted, not only in terms of the case study itself, but most importantly from the standpoint of the applicability of the evaluation framework
Forecasting Seismicity on Local to Regional Scale
Forecasting Seismicity on Local to Regional Scal
Isotopic composition (238U/235U) of some commonly used uranium reference materials
We have determined 238U/235U ratios for a suite of commonly used natural (CRM 112a, SRM 950a, and HU-1) and synthetic (IRMM 184 and CRM U500) uranium reference materials by thermal ionisation mass-spectrometry (TIMS) using the IRMM 3636 233U-236U double spike to accurately correct for mass fractionation. Total uncertainty on the 238U/235U determinations is estimated to be < 0.02% (2σ). These natural 238U/235U values are different from the widely used ‘consensus’ value (137.88), with each standard having lower 238U/235U values by up to 0.08%. The 238U/235U ratio determined for CRM U500 and IRMM 184 are within error of their certified values; however, the total uncertainty for CRM U500 is substantially reduced (from 0.1% to 0.02%). These reference materials are commonly used to assess mass spectrometer performance and accuracy, calibrate isotope tracers employed in U, U-Th and U-Pb isotopic studies, and as a reference for terrestrial and meteoritic 238U/235U variations. These new 238U/235U values will thus provide greater accuracy and reduced uncertainty for a wide variety of isotopic determinations
High-risk human papillomavirus (HPV) screening and detection in normal, healthy patient saliva samples: a pilot cluster randomized study
Background: The human papillomaviruses (HPV) are a large family of non-enveloped DNA viruses, mainly associated with cervical cancers. Recent epidemiologic evidence has suggested that HPV may be an independent risk factor for oropharyngeal cancers. Evidence now suggests HPV may modulate the malignancy process in some tobacco- and alcohol-induced oropharynx tumors, but might also be the primary oncogenic factor for inducing carcinogenesis among some non-smokers. More evidence, however, is needed regarding oral HPV prevalence among healthy adults to estimate risk. The goal of this study was to perform an HPV screening of normal healthy adults to assess oral HPV prevalence.
Methods: Healthy adult patients at a US dental school were selected to participate in this pilot study. DNA was isolated from saliva samples and screened for high-risk HPV strains HPV16 and HPV18 and further processed using qPCR for quantification and to confirm analytical sensitivity and specificity.
Results: Chi-square analysis revealed the patient sample was representative of the general clinic population with respect to gender, race and age (p \u3c 0.05). Four patient samples were found to harbor HPV16 DNA, representing 2.6% of the total (n = 151). Three of the four HPV16-positive samples were from patients under 65 years of age and all four were female and Hispanic (non-White). No samples tested positive for HPV18.
Conclusions: The successful recruitment and screening of healthy adult patients revealed HPV16, but not HPV18, was present in a small subset. These results provide new information about oral HPV status, which may help to contextualize results from other studies that demonstrate oral cancer rates have risen in the US among both females and minorities and in some geographic areas that are not solely explained by rates of tobacco and alcohol use. The results of this study may be of significant value to further our understanding of oral health and disease risk, as well as to help design future studies exploring the role of other factors that influence oral HPV exposure, as well as the short- and long-term consequences of oral HPV infection
Rupture by damage accumulation in rocks
The deformation of rocks is associated with microcracks nucleation and
propagation, i.e. damage. The accumulation of damage and its spatial
localization lead to the creation of a macroscale discontinuity, so-called
"fault" in geological terms, and to the failure of the material, i.e. a
dramatic decrease of the mechanical properties as strength and modulus. The
damage process can be studied both statically by direct observation of thin
sections and dynamically by recording acoustic waves emitted by crack
propagation (acoustic emission). Here we first review such observations
concerning geological objects over scales ranging from the laboratory sample
scale (dm) to seismically active faults (km), including cliffs and rock masses
(Dm, hm). These observations reveal complex patterns in both space (fractal
properties of damage structures as roughness and gouge), time (clustering,
particular trends when the failure approaches) and energy domains (power-law
distributions of energy release bursts). We use a numerical model based on
progressive damage within an elastic interaction framework which allows us to
simulate these observations. This study shows that the failure in rocks can be
the result of damage accumulation
Highlights from the first ten years of the New Zealand earthquake forecast testing center
We present highlights from the first decade of operation of the New Zealand Earthquake Forecast Testing Center of the Collaboratory for the Study of Earthquake Predictability (CSEP). Most results are based on reprocessing using the best available catalog, because the testing center did not consistently capture the complete real-time catalog. Tests of models with daily updating show that aftershock models incorporating Omori- Utsu decay can outperform long-term smoothed seismicity models with probability gains up to 1000 during major aftershock sequences. Tests of models with 3-month updating show that several models with every earthquake a precursor according to scale (EEPAS) model, incorporating the precursory scale increase phenomenon and without Omori-Utsu decay, and the double-branching model, with both Omori-Utsu and exponential decay in time, outperformed a regularly updated smoothed seismicity model. In tests of 5-yr models over 10 yrs without updating, a smoothed seismicity model outperformed the earthquake source model of the New Zealand National Seismic Hazard Model. The performance of 3-month and 5-yr models was strongly affected by the Canterbury earthquake sequence, which occurred in a region of previously low seismicity. Smoothed seismicity models were shown to perform better with more frequent updating. CSEP models were a useful resource for the development of hybrid time-varying models for practical forecasting after major earthquakes in the Canterbury and Kaikoura regions. © 2018 Seismological Society of America. All rights reserved
Earthquake swarms driven by aseismic creep in the Salton Trough, California
Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 112 (2007): B04405, doi:10.1029/2006JB004596.In late August 2005, a swarm of more than a thousand earthquakes between magnitudes 1 and 5.1 occurred at the Obsidian Buttes, near the southern San Andreas Fault. This swarm provides the best opportunity to date to assess the mechanisms driving seismic swarms along transform plate boundaries. The recorded seismicity can only explain 20% of the geodetically observed deformation, implying that shallow, aseismic fault slip was the primary process driving the Obsidian Buttes swarm. Models of earthquake triggering by aseismic creep can explain both the time history of seismic activity associated with the 2005 swarm and the ∼1 km/h migration velocity exhibited by this and several other Salton Trough earthquake swarms. A combination of earthquake triggering models and denser geodetic data should enable significant improvements in time-dependent forecasts of seismic hazard in the key days to hours before significant earthquakes in the Salton Trough.This material is based upon work supported by the National
Science Foundation under grant 0548785. R.B.L. was supported by a
WHOI postdoctoral research fellowship
Shipping as a Knowledge Industry: Research and Strategic Planning at Ocean Group
This chapter approaches the question of how transformations in the world of shipping relate to wider trends in business and general history through the lens of knowledge. It will investigate how technological and managerial knowledge was created, developed and exploited as a corporate resource from the 1950s onwards in Ocean Transport and Trading, one of the UK’s leading liner shipping firms. The chapter will, first, briefly discuss the resource-based view of the firm and the importance of knowledge as a corporate resource. It will then examine Ocean’s use of technological and operational knowledge in the post-war era. The following section examines the introduction of modern management concepts at Ocean from the late 1960s and their impact on corporate strategy. In conclusion, the chapter will argue that the introduction of managerial concepts of knowledge contributed to Ocean’s gradual withdrawal from shipping and transformation into a provider of global logistics services and that analyzing shipping as a knowledge industry helps make sense of the transformation of the industry
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