Application of a location model to fire stations in Rotterdam

This report is an outgrowth of a research project carried out by the Operations Research Group of Twente University of Technology in cooperation with the Department Fire-Brigade Affairs (Home Office) and the Rotterdam Fire Department. The objectives of the project were to determine the minimal number of fire stations, their locations and the number of first attendance pumpers, so that each point in town can be reached within a prescribed attendance time with sufficient equipment.\ud A road network approach was used for determining the set of possible location areas for fire stations followed by a set-covering approach for calculating the minimal number of stations. The hard points to tackle were the construction of robust networks, the determination of the possible location areas and the calculation of all the alternative locations of a minimal number of fire stations.\ud A simulation was carried out to test whether the solutions given by the network approach were realistic

A strategic approach for the ambulance covering of the province of Friesland

In the summer of 1995 the University of Twente, commissioned by the Province of Friesland, carried out research into the consequences of alternative locations for ambulances. The approach to this research was based on a network model, which represents the area to be covered. With this model the attendance times for the ambulances can be determined based on a shortest route algorithm. The attendance time is the time between the dispatching of the ambulance by Central Alarm after an emergency call and its arrival at the patient. The attendance times are compared with the norm as described by the Dutch law. The research concentrated on the Southwest and Northeast of the Province. In view of the norm of 15 minutes for the attendance time, the proposed alternative in the Southwest is the closing of one site and the moving of another. This is feasible under the condition that there will always be well-trained manpower available at the stations, and especially at the site which is moved. In the Northeast the moving of one post and the closure of another has no disadvantages with regard to attendance times. These conclusions appear to give a reliable picture of the real-world situation based on a conservative approach with the network model used, and, that higher travel speeds than those assumed are possible. \u

Route information from a central route planner

We present a discussion of a problem posed by researchers of the comapny Ericsson, namely, to estimate the fraction of road users in a road network that must participate in a central route planning scheme such that travel time predictions improve significantly. The aim of this work is to derive a measure of travel time performance depending on the number of road users who are participating in the central route planner. The approach is mainly of a statistical nature

Solving the Sports League Scheduling Problem with Tabu Search

In this paper we present a tabu approach for a version of the Sports League Scheduling Problem. The approach adopted is based on a formulation of the problem as a Constraint Satisfaction Problem (CSP). Tests were carried out on problem instances of up to 40 teams representing 780 integer variables with 780 values per variable. Experimental results show that this approach outperforms some existing methods and is one of the most promising methods for solving problems of this type

Safety and technical efficacy of early minimally invasive endoscopy-guided surgery for intracerebral haemorrhage:the Dutch Intracerebral haemorrhage Surgery Trial pilot study

Background: Previous randomised controlled trials could not demonstrate that surgical evacuation of intracerebral haemorrhage (ICH) improves functional outcome. Increasing evidence suggests that minimally invasive surgery may be beneficial, in particular when performed early after symptom onset. The aim of this study was to investigate safety and technical efficacy of early minimally invasive endoscopy-guided surgery in patients with spontaneous supratentorial ICH. Methods: The Dutch Intracerebral Haemorrhage Surgery Trial pilot study was a prospective intervention study with blinded outcome assessment in three neurosurgical centres in the Netherlands. We included adult patients with spontaneous supratentorial ICH ≥10mL and National Institute of Health Stroke Scale (NIHSS) score ≥2 for minimally invasive endoscopy-guided surgery within 8 h after symptom onset in addition to medical management. Primary safety outcome was death or increase in NIHSS ≥4 points at 24 h. Secondary safety outcomes were procedure-related serious adverse events (SAEs) within 7 days and death within 30 days. Primary technical efficacy outcome was ICH volume reduction (%) at 24 h. Results: We included 40 patients (median age 61 years; IQR 51–67; 28 men). Median baseline NIHSS was 19.5 (IQR 13.3–22.0) and median ICH volume 47.7mL (IQR 29.4–72.0). Six patients had a primary safety outcome, of whom two already deteriorated before surgery and one died within 24 h. Sixteen other SAEs were reported within 7 days in 11 patients (of whom two patients that already had a primary safety outcome), none device related. In total, four (10%) patients died within 30 days. Median ICH volume reduction at 24 h was 78% (IQR 50–89) and median postoperative ICH volume 10.5mL (IQR 5.1–23.8). Conclusions: Minimally invasive endoscopy-guided surgery within 8 h after symptom onset for supratentorial ICH appears to be safe and can effectively reduce ICH volume. Randomised controlled trials are needed to determine whether this intervention also improves functional outcome. Trial registration: Clinicaltrials.gov : NCT03608423, August 1st, 2018.</p

A Randomized Trial of Intravenous Alteplase before Endovascular Treatment for Stroke

The value of administering intravenous alteplase before endovascular treatment (EVT) for acute ischemic stroke has not been studied extensively, particularly in non-Asian populations. METHODS We performed an open-label, multicenter, randomized trial in Europe involving patients with stroke who presented directly to a hospital that was capable of providing EVT and who were eligible for intravenous alteplase and EVT. Patients were randomly assigned in a 1:1 ratio to receive EVT alone or intravenous alteplase followed by EVT (the standard of care). The primary end point was functional outcome on the modified Rankin scale (range, 0 [no disability] to 6 [death]) at 90 days. We assessed the superiority of EVT alone over alteplase plus EVT, as well as noninferiority by a margin of 0.8 for the lower boundary of the 95% confidence interval for the odds ratio of the two trial groups. Death from any cause and symptomatic intracerebral hemorrhage were the main safety end points. RESULTS The analysis included 539 patients. The median score on the modified Rankin scale at 90 days was 3 (interquartile range, 2 to 5) with EVT alone and 2 (interquartile range, 2 to 5) with alteplase plus EVT. The adjusted common odds ratio was 0.84 (95% confidence interval [CI], 0.62 to 1.15; P=0.28), which showed neither superiority nor noninferiority of EVT alone. Mortality was 20.5% with EVT alone and 15.8% with alteplase plus EVT (adjusted odds ratio, 1.39; 95% CI, 0.84 to 2.30). Symptomatic intracerebral hemorrhage occurred in 5.9% and 5.3% of the patients in the respective groups (adjusted odds ratio, 1.30; 95% CI, 0.60 to 2.81). CONCLUSIONS In a randomized trial involving European patients, EVT alone was neither superior nor noninferior to intravenous alteplase followed by EVT with regard to disability outcome at 90 days after stroke. The incidence of symptomatic intracerebral hemorrhage was similar in the two groups