Offloading Time Research Articles

On Detecting Spectrum Opportunities for Cognitive Vehicular Networks in the TV White Space

We overview the challenges related to spectrum awareness in the vehicular environment, with emphasis on awareness in the TV licensed band. In the vehicular environment the cognitive radio can help to: 1) satisfy capacity demand for Intelligent Transportation Systems (ITS) applications; and 2) offload time insensitive applications from the ITS dedicated spectrum. However, using simple propagation models we show that neither sensing, nor geolocation database lookup alone can provide sufficient incumbent protection. Collaboration among the sensors to take advantage of spatial diversity is difficult due to the rapidly changing network topology. Nevertheless, mobility provides the opportunity to use time diversity at each sensor. We also discuss the influence of sensing subsystem design on the vehicular cognitive network medium access (MAC) sublayer. Whenever appropriate, we evaluate applicability of the requirements imposed by the Federal Communications Commission (FCC) and the IEEE 802.22 standard to the cognitive vehicular networks.

Effect of an electronic medical record information system on emergency department performance

To determine whether implementation of the Cerner FirstNet electronic medical record system was associated with any change in emergency department (ED) performance. A retrospective observational study conducted during a 6-03 period in 2009 after the introduction of FirstNet and a corresponding 6-03 control period in 2008 when the Emergency Department Information System (EDIS) was operational. Data from all patients presenting to the ED during each period were extracted from each system and analysed for changes in key performance indicators (KPIs). Potential confounding variables, including total number of ED presentations, ED occupancy, ED staffing levels and triage category distribution, were also collected. Waiting time for all patients; waiting time, treatment time and total time for patients discharged from the ED; proportion of patients who did not wait to be seen by a doctor (DNW rate); and proportion of ambulance offload waiting times longer than 30 minutes. We found a reduction in performance with respect to ED KPIs after implementation of the FirstNet system. There were increases in the waiting time for all patients (median, 40 min v 78 min), and the waiting time (median, 49 min v 87 min), treatment time (median, 128 min v 147 min) and total time (median, 214 min v 280 min) for patients discharged from the ED. There were increases in the DNW rate (8.3% v 15.6%) and the proportion of ambulance offload times longer than 30 minutes (10.5% v 13.3%). All differences were statistically significant (P < 0.05). Implementation of the FirstNet electronic medical record system was associated with deterioration in ED KPIs.

Ambulance Diversion and Emergency Department Offload Delay: Resource Document for the National Association of EMS Physicians Position Statement

The emergency medical services (EMS) system is a component of a larger health care safety net and a key component of an integrated emergency health care system. EMS systems, and their patients, are significantly impacted by emergency department (ED) crowding. While protocols designed to limit ambulance diversion may be effective at limiting time on divert status, without correcting overall hospital throughput these protocols may have a negative effect on ED crowding and the EMS system. Ambulance offload delay, the time it takes to transfer a patient to an ED stretcher and for the ED staff to assume the responsibility of the care of the patient, may have more impact on ambulance turnaround time than ambulance diversion. EMS administrators and medical directors should work with hospital administrators, ED staff, and ED administrators to improve the overall efficiency of the system, focusing on the time it takes to get ambulances back into service, and therefore must monitor and address both ambulance diversions and ambulance offload delay. This paper is the resource document for the National Association of EMS Physicians position statement on ambulance diversion and ED offload time. Key words: ambulance; EMS; diversion; bypass; offload; delay

Optimization of drying performance considering driving conditions

Compressed air can be used as an energy source for brake systems in medium-heavy and heavy-duty commercial vehicles. The moisture in compressed air, which is due to high temperature and humidity, can be eliminated by using an air dryer. In this paper, drying performance data for a cartridge were obtained and used to develop a drying performance program, to predict the moisture and relative humidity in the air tanks of vehicles. The on-load time, off-load time, air flow, duty cycle, humidity and dew point temperature were calculated according to air consumption. The validity of the program was verified, and it was shown to be able to predict humidity changes in the air tank. The air tank capacity was increased from 100 to 130 to reduce the duty cycle. Therefore, the regeneration rate decreased from 18% to 15%, but the dew point depression temperature (ΔT) remained above 30°C. The duty cycle decreased from 50% to 43%, and the total operation time and power consumption of the air compressor were reduced. In conclusion, fuel savings were obtained by changing the parameters to optimize the system.

The potential adverse patient effects of ambulance ramping, a relatively new problem at the interface between prehospital and ED care

Ambulance 'ramping,' when a transported patient has a prolonged wait within the vehicle on arrival at a hospital because there are no vacant care areas or beds available in the hospital's emergency department (ED), is a problem of increasing importance in Australia. The impact of delayed off-loading and therefore delayed ED care for patients stuck in ramped ambulance queues, as well as the interaction between the urgency of the clinical condition, position in the queue, and patient outcomes, warrants further study. Delay in off-load time has greater clinical consequences for the sicker patients stuck at the end of ambulance queues on arrival to the hospital than for less ill patients located in ambulances ahead of them. Difficulty off-loading patients who need urgent resuscitation results in delayed ED care and worse patient outcomes, especially so in time-critical conditions. Moreover, it is not possible to use ambulance crews and vehicles for other jobs whilst they are waiting to off-load a patient. Patients in an ambulance queue, awaiting off-loading on arrival at the hospital, are not currently subjected to a formalized, well-conducted triage process. Even if ramped ambulance triage were performed, and a sick patient upgraded for more urgent off-loading, repositioning ambulances further ahead in the queue or transferring patients on stretchers from a back-of-queue ambulance to the ED through the confines of a crowded ambulance approach bay poses substantial occupational hazards.

The Impact of Emergency Department Paramedic Staffing on Emergency Medical Services Unit Off-load Time

The Impact of Emergency Department Paramedic Staffing on Emergency Medical Services Unit Off-load Time

Impact of Emergency Department Bed Capacity on Emergency Medical Services Unit Off-load Time

Impact of Emergency Department Bed Capacity on Emergency Medical Services Unit Off-load Time

Cyclic stress effects on the grain boundary cracking in Al-Mg solid solution

The difference in the grain boundary deformation between statically and cyclically crept specimens of Al-Mg solid solution has been investigated at the temperature of 580 K and for the peak stress level of 15 to 20 M Pa. In statically crept specimens, the grain boundaries deform irregularly and no crack is formed either at the triple point or along the serrated boundaries. However, in cyclically crept specimens, where the stress frequency, stress amplitude and the ratio of on-load to off-load time are 3 cycles per minute, 90% of maximum peak stress and less than 1, respectively, the grain boundaries remain smooth and wedge-type cracks are formed at the triple points, which results in intercrystalline fracture. On the basis of the experimental observations it is believed that cyclic stressing enhances grain boundary sliding through an accelerated recovery with the help of mechanically generated excess vacancies during cycling. However, due to the constraints of the grain alignment, boundary sliding becomes very difficult and creates an intercrystalline fracture at a triple point. On the other hand, under static stress, since the grain boundary is serrated to decrease the stress concentration at a triple point, a crack hardly forms at the triple point.