A Study of the Dynamic Features of a Wall-Reattachment Fluid Amplifier

1964 ◽  
Vol 86 (4) ◽  
pp. 819-826 ◽  
Author(s):  
H. R. Muller
Keyword(s):  
Response Time ◽  
Transient Flow ◽  
Time Interval ◽  
Control Input ◽  
Dynamic Features ◽  
Transport Time ◽  
Switching Model ◽  
Supply Pressure ◽  
Dynamic Case ◽  
Control Port

The paper describes the characteristics of a wall-reattachment fluid amplifier. The switching of the jet from the wall to which it is attached to the opposite one is analyzed. It is shown that the control input characteristic that is measured statically can be applied in the dynamic case. This fact is far from being trivial, as the transient flow patterns occurring during the switching process are basically different from the stationary patterns. The variation of the response time (time interval between when a control pulse is applied at the control port and when the output signal is received at the other receiver) with the control supply pressure is given and compared with the results obtained from a simple analytical switching model. For a control supply pressure of 40 percent of the supply pressure, the response time is 5 to 8 times the transport time of a particle traveling 20 times the nozzle distance.

Abstract TP245: Variance in Ems Run Times by Receiving Hospital for Stroke Patients in San Diego County

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Amelia Kenner-brininger ◽  
Lindsay Olson-Mack ◽  
Lorraine Calzone ◽  
Kristi L Koenig ◽  
Thomas M Hemmen
Keyword(s):  
Response Time ◽  
San Diego ◽  
Life Support ◽  
Prehospital Care ◽  
Advanced Life Support ◽  
San Diego County ◽  
Stroke Patients ◽  
Transport Time ◽  
Stroke Registry ◽  
Few Data

Background: Emergency Medical Services (EMS) play an important role as initial providers after stroke. Few data are available that capture Stroke Receiving System and EMS response and transport data. We used a stroke registry from a community of 3.3 million residents, 18 stroke receiving centers, and 19 ground transporting advanced life support EMS agencies to evaluate EMS response time, scene time, and transport times. Our aim was to inform the stroke community about duration of EMS care and guide future prehospital interventions. Methods: We included all cases from the San Diego County Stroke Registry arriving by EMS with associated computer automated dispatch (CAD) record and base hospital record (BHR) from July 2017 through December 2018. Records were linked on the EMS incident number, reviewed for accuracy. We analyzed EMS response, scene, transport and total run times (enroute to arrival) by receiving hospital. Results: Between July 2017 and December 2018 2,376 EMS patients were transported to 18 hospitals. Volume per hospital ranged from 11 to 483 patients over the study period. Mean (±SD) response time was 7.0 (±3.7) minutes, range: 5.3 to 9.3 minutes between hospitals. Mean (±SD) scene time was 13.1 (±5.2) minutes, range: 10.5 to 15.0 minutes between hospitals. Transport time averaged 13.8 (±7.7) minutes, range: 8.3 to 23.8 minutes between hospitals (IQR=8.5-17.9). The mean (±SD) total EMS run time was 33.8 (±10.8) minutes, range: 26.4 to 44.9 minutes between hospitals (IQR=26.4-39.9). Conclusion: Only minor variations in EMS response and scene times were observed across the Stroke Receiving Centers. However, transport time showed greater variation and contributed to the differences in total EMS run times. Many systems had short transport times, limiting prehospital interventions. Next steps include studying factors contributing to transport time variation to inform prehospital care and triage decisions of possible stroke patients to optimize transport times.

Abstract 249: The Effect of Response Time on Out-Of-Hospital Cardiac Arrest Survival Varies by Patient Subpopulation

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_2) ◽  
Author(s):  
Clara Stoesser ◽  
Justin Boutilier ◽  
Christopher L Sun ◽  
Katie N Dainty ◽  
Steve Lin ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Regression Analysis ◽  
Response Time ◽  
Time Interval ◽  
Probability Of Survival ◽  
Subgroup Analyses ◽  
Impact On Survival ◽  
The Impact ◽  
Cardiac Arrest Survival ◽  
Hospital Cardiac Arrest

Itroduction: Previous research has quantified the impact of EMS response time on the probability of survival from OHCA, but the impact on different subpopulations is currently unknown. Aim: To investigate how response time affects OHCA survival for different patient subpopulations. Methods: We conducted a logistic regression analysis on non-EMS witnessed OHCAs of presumed cardiac etiology from the Toronto Regional RescuNet between January 1, 2007 and December 31, 2016. We predicted survival using age, sex, public location, presenting rhythm, bystander witnessed, bystander resuscitation, and response time, defined as the time interval from 911 call to EMS arrival at the patient. We conducted subgroup analyses to quantify the effect of response time on survival for eight different subpopulations: public, private, bystander resuscitation, no bystander resuscitation, patients ≥65, patients <65, witnessed, and unwitnessed OHCA. We also quantified the effect of response time on survival for pairwise intersections of the subpopulations. We compared our results to Valenzuela et al. (1997), which suggests survival odds decrease by 10% for each minute delay in response time. Results: We identified 22,988 OHCAs. Overall, a one-minute delay in EMS response time was associated with a 13.2% reduction in the odds of survival. The reduction varied by subpopulation, ranging from a 7.2% reduction in survival odds for unwitnessed arrests to a 16.4% reduction in survival odds for arrests with bystander resuscitation. Response time had the largest impact on survival for the subpopulation of OHCAs that were both witnessed and received bystander resuscitation (17.4% reduction in survival odds). Conclusion: The effect of a one-minute delay in EMS response on the odds of survival from OHCA can be as low as a 7.2% reduction and as high as a 17.4% reduction. This variability contrasts with the currently accepted 10% rule that is assumed across the entire population.

scholarly journals Finite-time Lagrangian transport analysis: stable and unstable manifolds of hyperbolic trajectories and finite-time Lyapunov exponents

2010 ◽  
Vol 17 (1) ◽  
pp. 1-36 ◽  
Author(s):  
M. Branicki ◽  
S. Wiggins
Keyword(s):  
Dynamical Systems ◽  
Finite Time ◽  
Vector Fields ◽  
Transient Flow ◽  
Time Interval ◽  
Stable And Unstable Manifolds ◽  
Lagrangian Transport ◽  
Transport Barriers ◽  
Unstable Manifolds ◽  
Hyperbolic Trajectories

Abstract. We consider issues associated with the Lagrangian characterisation of flow structures arising in aperiodically time-dependent vector fields that are only known on a finite time interval. A major motivation for the consideration of this problem arises from the desire to study transport and mixing problems in geophysical flows where the flow is obtained from a numerical solution, on a finite space-time grid, of an appropriate partial differential equation model for the velocity field. Of particular interest is the characterisation, location, and evolution of transport barriers in the flow, i.e. material curves and surfaces. We argue that a general theory of Lagrangian transport has to account for the effects of transient flow phenomena which are not captured by the infinite-time notions of hyperbolicity even for flows defined for all time. Notions of finite-time hyperbolic trajectories, their finite time stable and unstable manifolds, as well as finite-time Lyapunov exponent (FTLE) fields and associated Lagrangian coherent structures have been the main tools for characterising transport barriers in the time-aperiodic situation. In this paper we consider a variety of examples, some with explicit solutions, that illustrate in a concrete manner the issues and phenomena that arise in the setting of finite-time dynamical systems. Of particular significance for geophysical applications is the notion of flow transition which occurs when finite-time hyperbolicity is lost or gained. The phenomena discovered and analysed in our examples point the way to a variety of directions for rigorous mathematical research in this rapidly developing and important area of dynamical systems theory.

System Implications of the Ambulance Arrival-to-Patient Contact Interval on Response Interval Compliance

1994 ◽  
Vol 9 (4) ◽  
pp. 230-232 ◽  
Author(s):  
Jack P. Campbell ◽  
Matthew C. Gratton ◽  
Joseph A. Salomone ◽  
Daniel J. Lindholm ◽  
William A. Watson
Keyword(s):  
Response Time ◽  
Statistical Significance ◽  
Public Utility ◽  
Third Party ◽  
Measuring System ◽  
System Response ◽  
Time Interval ◽  
Patient Access ◽  
Time Intervals ◽  
Chi Square

AbstractBackground:Background: In some emergency medical services (EMS) system designs, response time intervals are mandated with monetary penalties for noncompliance. These times are set with the goal of providing rapid, definitive patient care. The time interval of vehicle at scene-to-patient access (VSPA) has been measured, but its effect on response time interval compliance has not been determined.Purpose:To determine the effect of the VSPA interval on the mandated code 1 (<9 min) and code 2 (<13 min) response time interval compliance in an urban, public-utility model system.Methods:A prospective, observational study used independent third-party riders to collect the VSPA interval for emergency life-threatening (code 1) and emergency nonlife-threatening (code 2) calls. The VSPA interval was added to the 9-1-1 call-to-dispatch and vehicle dispatch-to-scene intervals to determine the total time interval from call received until paramedic access to the patient (9-1-1 call-to-patient access). Compliance with the man dated response time intervals was determined using the traditional time intervals (9-1-1 call-to-scene) plus the VSPA time intervals (9-1-1 call-to-patient access). Chi-square was used to determine statistical significance.Results:Of the 216 observed calls, 198 were matched to the traditional time intervals. Sixty three were code 1, and 135 were code 2. Of the code 1 calls, 90.5% were compliant using 9-1-1 call-to-scene intervals dropping to 63.5% using 9-1-1 call-to-patient access intervals (p<0.0005). Of the code 2 calls, 94.1% were compliant using 9-1-1 call-to-scene intervals. Compliance decreased to 83.7% using 9-1-1 call-to-patient access intervals (p = 0.012).Conclusion:The addition of the VSPA interval to the traditional time intervals impacts system response time compliance. Using 9-1-1 call-to-scene compliance as a basis for measuring system performance underestimates the time for the delivery of definitive care. This must be considered when response time interval compliances are defined.

Prehospital Emergency Medical Services Departure Interval: Does Patient Age Matter?

2016 ◽  
Vol 31 (6) ◽  
pp. 608-613 ◽  
Author(s):  
Bruno Schnegg ◽  
Mathieu Pasquier ◽  
Pierre-Nicolas Carron ◽  
Bertrand Yersin ◽  
Fabrice Dami
Keyword(s):  
Response Time ◽  
Emergency Medical Services ◽  
Time Of Day ◽  
Medical Services ◽  
Time Interval ◽  
Patient Age ◽  
Emergency Medical ◽  
Patient Âgé ◽  
Prehospital Emergency ◽  
The Impact

AbstractIntroductionThe concept of response time with minimal interval is intimately related to the practice of emergency medicine. The factors influencing this time interval are poorly understood.ProblemIn a process of improvement of response time, the impact of the patient’s age on ambulance departure intervals was investigated.MethodThis was a 3-year observational study. Departure intervals of ambulances, according to age of patients, were analyzed and a multivariate analysis, according to time of day and suspected medical problem, was performed.ResultsA total of 44,113 missions were included, 2,417 (5.5%) in the pediatric group. Mean departure delay for the adult group was 152.9 seconds, whereas it was 149.3 seconds for the pediatric group (P =.018).ConclusionA statistically significant departure interval difference between missions for children and adults was found. The difference, however, probably was not significant from a clinical point of view (four seconds).SchneggB, PasquierM, CarronPN, YersinB, DamiF. Prehospital Emergency Medical Services departure interval: does patient age matter?Prehosp Disaster Med. 2016;31(6):608–613.

scholarly journals Frequent Mobile Electronic Medical Records Users Respond More Quickly to Emergency Department Consultation Requests: Retrospective Quantitative Study

10.2196/14487 ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. e14487 ◽  
Author(s):  
Kwang Yul Jung ◽  
SuJin Kim ◽  
Kihyung Kim ◽  
Eun Ju Lee ◽  
Kyunga Kim ◽  
...  
Keyword(s):  
Emergency Department ◽  
Response Time ◽  
Electronic Medical Records ◽  
Medical Records ◽  
Inverse Relationship ◽  
Secondary Outcome ◽  
Time Interval ◽  
Care Providers ◽  
Significant Inverse Relationship ◽  
The Relationship

Background Specialty consultation is a critical aspect of emergency department (ED) practice, and a delay in providing consultation might have a significant clinical effect and worsen ED overcrowding. Although mobile electronic medical records (EMR) are being increasingly used and are known to improve the workflow of health care providers, limited studies have evaluated their effectiveness in real-life clinical scenarios. Objective For this study, we aimed to determine the association between response duration to an ED specialty consultation request and the frequency of mobile EMR use. Methods This retrospective study was conducted in an academic ED in Seoul, South Korea. We analyzed EMR and mobile EMR data from May 2018 to December 2018. Timestamps of ED consultation requests were retrieved from a PC-based EMR, and the response interval was calculated. Doctors’ log frequencies were obtained from the mobile EMR, and we merged data using doctors’ deidentification numbers. Pearson’s product-moment correlation was performed to identify this association. The primary outcome was the relationship between the frequency of mobile EMR usage and the time interval from ED request to consultation completion by specialty doctors. The secondary outcome was the relationship between the frequency of specialty doctors’ mobile EMR usage and the response time to consultation requests. Results A total of 25,454 consultations requests were made for 15,555 patients, and 252 specialty doctors provided ED specialty consultations. Of the 742 doctors who used the mobile EMR, 208 doctors used it for the specialty consultation process. After excluding the cases lacking essential information, 21,885 consultations with 208 doctors were included for analysis. According to the mobile EMR usage pattern, the average usage frequency of all users was 13.3 logs/day, and the average duration of the completion of the specialty consultation was 51.7 minutes. There was a significant inverse relationship between the frequency of mobile EMR usage and time interval from ED request to consultation completion by specialty doctors (coefficient=–0.19; 95% CI –0.32 to –0.06; P=.005). Secondary analysis with the response time was done. There was also a significant inverse relationship between the frequency of specialty doctors’ mobile EMR usage and the response time to consultation requests (coefficient=–0.18; 95% CI –0.30 to –0.04; P=.009). Conclusions Our findings suggest that frequent mobile EMR usage is associated with quicker response time to ED consultation requests.

scholarly journals То the synchronous work of pulsed sources of seismic waves

2019 ◽  
pp. 75-79
Author(s):  
S. P. Ekomasov
Keyword(s):  
Control System ◽  
Response Time ◽  
Half Space ◽  
Seismic Waves ◽  
Time Interval ◽  
Shock Interaction ◽  
Seismic Efficiency ◽  
Pulse Type ◽  
The Stability ◽  
The Moment

Researches have been made with the use of a hydropneumatic source of seismic waves. This source on the realized efforts of the shock interaction with a soil half-space considerably exceeds all known designs of radiators (sources) of pulse type. In this regard it shows higher seismic efficiency. The most important characteristic of the work of the pulse sources of seismic waves is a stability of the response time — a time interval from the moment of giving of a signal for producing of the blow until the very blow. Only with the achievement of the necessary stability the work in the mode of grouping of sources and accumulation of signals is possible. Features of the formation of response time of a hydropneumatic source are given. The analysis of the assessment of the parameters of synchronism of the pulse sources is made by a modem control system of their work. An influence of the rigidity of the soil on the assessment of stability of the response time and synchronism is shown. The system of the assessment of the stability used in the existing pulse sources at its application does not reflect the actual stability of response time in the radiators possessing a big force of blow.

scholarly journals Response Times of Motorcycle Ambulances during the COVID-19 Pandemic

2020 ◽  
Vol 8 (T1) ◽  
pp. 526-529
Author(s):  
Korakot Apiratwarakul ◽  
Kamonwon Ienghong ◽  
Vajarabhongsa Bhudhisawasdi ◽  
Dhanu Gaysonsiri ◽  
Somsak Tiamkao
Keyword(s):  
Response Time ◽  
Response Times ◽  
Operation Time ◽  
Cross Sectional Study ◽  
Average Response Time ◽  
Transport Time ◽  
Cross Sectional ◽  
Normal Period ◽  
System Data ◽  
Information Database

BACKGROUND: Motorcycles (motorlance) are often deployed as ambulances to the scene of an emergency to reduce response time. The COVID-19 pandemic has affected emergency medical services (EMS) in Thailand in many respects, and this study was conducted to examine its effect on motorlance operation time. AIM: The aim of the study was to examine motorlance operation time during the COVID-19 pandemic in comparison to normal periods. METHODS: This cross-sectional study examined all EMS motorlance operations dispatched from Srinagarind Hospital (Thailand). Data were collected from the Srinagarind Hospital EMS operation database and hospital information database system. Data from June 1, 2018, to December 31, 2019 (normal period) were compared with those from January 13 to April 21, 2020 (COVID-19). RESULTS: Eight hundred seventy-one EMS operations were examined over two periods. Mean patient age during the COVID-19 pandemic was 41.5 ± 6.2 years, and 54.6% (n = 59) were male. Average response time was 6.20 ± 1.35 min during the normal period and 3.48 ± 1.01 min during the pandemic (p = 0.021). Transport time was also significantly shorter during the latter period (2.35 vs. 5.20 min). CONCLUSIONS: Motorlance response and transport time during the COVID-19 pandemic were significantly shorter than usual.

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