This paper presents a three-dimensional (3-D) localization system for ultra-wideband (UWB) impulsive noise sources. The localization algorithm is in terms of time difference of arrival (TDOA). Firstly, a feasibility study of the 3-D localization scheme is carried out numerically. Then, the effectiveness and limitation of the scheme are revealed. Our proposal is validated by measurement in an op...

BACKGROUND AND PURPOSE Enrollment in acute stroke trials at a stroke center with multiple study protocols may delay the initiation of intravenous thrombolytics in patients who present within 3 hours of symptom onset. METHODS We studied all patients presenting with acute ischemic stroke over the past 3.5 years who qualified for thrombolysis within 3 hours of symptom onset. We collected demogra...

We establish heavy-traffic limits for the arrival and workload processes in a single-server queue with a time-varying arrival-rate function. We establish limits at and before a critical point, the onset of critical loading, where the arrival-rate function approaches its critical value from below. We extend results by Newell (1968) and Mandelbaum and Massey (1995) and present alternative views o...

BACKGROUND AND PURPOSE There is evidence that high-volume hospitals may produce better patient outcomes. We aimed to identify whether there were any associations between hospital thrombolysis volume and speed of thrombolysis (tissue-type plasminogen activator [tPA]) administration in patients with ischemic stroke. METHODS Data were drawn from 2 national clinical audits in England: the Stroke ...

BACKGROUND To evaluate the performance of a novel triage system for Transient Ischemic Attack (TIA) units built upon an existent clinical prediction rule (CPR) to reduce time to unit arrival, relative to the time of symptom onset, for true TIA and minor stroke patients. Differentiating between true and false TIA/minor stroke cases (mimics) is necessary for effective triage as medical interventi...

This paper studies the pattern of departure times at a single bottleneck, under general heterogeneous preferred arrival times. It delivers three main outputs. Firstly, the existence of equilibrium is proven without the classical ”S-shape” assumption on the distribution of preferred arrival time i.e. that demand, represented by the flow rate of preferred arrival times, may only exceed bottleneck...

INTRODUCTION Intravenous tissue plasminogen activator (tPA) within 3 hours of stroke onset is a licensed proven therapy for ischaemic stroke, with recent trial data showing benefit up to 4.5 hours. We previously published in this journal data of a survey conducted in 2004 showing only 9% of ischaemic stroke patients presenting to the Singapore General Hospital (SGH) arrived within 2 hours of on...

Arrival Time to Stroke Unit as Crucial a Measure as Arrival Time to Emergency Department To the Editor: We concur with Alexandrov in her recent editorial that “late arrival to the hospital after the onset of acute stroke symptoms is a plague of unheralded proportion. . . ”.1 We are currently conducting a large multicenter, clustered randomized trial in 19 acute stroke units in NSW, Australia.2 ...