scholarly journals CFD Analyses: The Effect of Pressure Suction and Airflow Velocity on Coronavirus Dispersal

2021 ◽  
Vol 11 (16) ◽  
pp. 7450
Author(s):  
Bushra Obeidat ◽  
Odi Fawwaz Alrebei ◽  
Ibrahim Atef Abdallah ◽  
Eman F. Darwish ◽  
Abdulkarem Amhamed
Keyword(s):  
Interior Design ◽  
Cfd Simulation ◽  
Ventilation System ◽  
University Hospital ◽  
Cfd Analyses ◽  
Surrounding Areas ◽  
Pressure Suction ◽  
Virus Spreading ◽  
Hospital Emergency Departments ◽  
The Impact

Hospital emergency departments (EDs) are hubs for highly transmissible infectious diseases, posing the highest risk of viral infection transmission. With the current COVID-19 outbreak, it has become clear that the ED design needs to be altered in order to be successful in containing the pandemic. The purpose of this study is to use a computational fluid dynamics (CFD) simulation to evaluate the ventilation system design for an emergency department at a university hospital. The kinetic energy and velocity patterns of turbulence were analyzed to determine which areas of the ED were most susceptible to viral transmission. Additionally, the impact of pressure suction on COVID-19 dispersion has been investigated. Three critical areas of the ED, overnight patient beds, surgical rooms, and resuscitation rooms, all had much higher air velocity, dispersion, and mixing levels than the rest of the department’s spaces, according to the simulation findings. Air transmission from these sites to adjacent regions is a possibility in the scenario studied, increasing the likelihood of the virus spreading from these locations and infecting people in the surrounding areas. The results of these simulations may be utilized to provide recommendations to the hospital administration about the placement of inlets and outlets, the separation of areas, and the interior design of the spaces and corridors.

Prediction of Ventilation Effectiveness for LM9000 Package With Machine Learning

2020 ◽  
Author(s):  
Alessandro Corsini ◽  
Giovanni Delibra ◽  
Marco Giovannelli ◽  
Gabriele Lucherini ◽  
Stefano Minotti ◽  
...  
Keyword(s):  
Machine Learning ◽  
Gas Turbines ◽  
Cfd Simulation ◽  
Ventilation System ◽  
Computational Time ◽  
Suggested Approach ◽  
Gas Leakage ◽  
Post Process ◽  
Artificial Neural ◽  
Cfd Analyses

Abstract Gas turbines usually are installed inside an enclosure, which is used as protection from the external environment and to provide an acoustic insulation. A ventilation system is required to control the temperature inside the enclosed volume and to dilute any potential gas leakage that may come from faulty pipes or flanges. The system has to be properly designed to avoid any unexpected explosion which would generate an overpressure not contained by enclosure walls. The most common approach to predict the effectiveness of the ventilation system requires to perform CFD analyses, which are very expensive in computational terms. A new approach has been proposed by authors, using machine learning and artificial neural networks (ANN) to identify the poorly ventilated zones. This methodology has been further developed, optimized and applied to a real gas turbine packages of new generation. In the present paper the authors will show the application of this procedure to the LM9000 package and the comparison with the results predicted using conventional CFD techniques. The tangible improvement introduced by this methodology is that the computational time is reduced from about three weeks with the common CFD approach to few minutes. The artificial neural network is developed in a Python environment that is applied during the CFX post-process phase of a steady state CFD simulation, providing results equivalent to unsteady CFD simulation. Besides the immediate benefits of this particular application, the suggested approach looks to be a great candidate to substitute the conventional and time-consuming CFD simulations with a fast post-processing algorithm that is able to learn and self-optimize as long as it is used.

scholarly journals Impact of HPC and Automated CFD Simulation Processes on Virtual Product Development—A Case Study

2021 ◽  
Vol 11 (14) ◽  
pp. 6552
Author(s):  
Christopher Lange ◽  
Patrick Barthelmäs ◽  
Tobias Rosnitschek ◽  
Stephan Tremmel ◽  
Frank Rieg
Keyword(s):  
Product Development ◽  
High Performance ◽  
Cfd Simulation ◽  
Computing Time ◽  
Point Of View ◽  
Before And After ◽  
Massively Parallel Computing ◽  
Cfd Analyses ◽  
Virtual Product Development ◽  
The Impact

High-performance computing (HPC) enables both academia and industry to accelerate simulation-driven product development processes by providing a massively parallel computing infrastructure. In particular, the automation of high-fidelity computational fluid dynamics (CFD) analyses aided by HPC systems can be beneficial since computing time decreases while the number of significant design iterations increases. However, no studies have quantified these effects from a product development point of view yet. This article evaluates the impact of HPC and automation on product development by studying a formula student racing team as a representative example of a small or medium-sized company. Over several seasons, we accompanied the team, and provided HPC infrastructure and methods to automate their CFD simulation processes. By comparing the team’s key performance indicators (KPIs) before and after the HPC implementation, we were able to quantify a significant increase in development efficiency in both qualitative and quantitative aspects. The major aerodynamic KPI increased up to 115%. Simultaneously, the number of expedient design iterations within one season increased by 600% while utilizing HPC. These results prove the substantial benefits of HPC and automation of numerical-intensive simulation processes for product development.

scholarly journals USING CFD SIMULATION TO INVESTIGATE THE IMPACT OF FRESH AIR VALVES ON POULTRY HOUSE AERODYNAMICS IN CASE OF A SIDE VENTILATION SYSTEM

2020 ◽  
pp. 155-164
Author(s):  
Viktor Trokhaniak ◽  
Ivan Rogovskii ◽  
Luidmyla Titova ◽  
Zoriana Dziubata ◽  
Petro Luzan ◽  
...  
Keyword(s):  
Large Scale ◽  
Cfd Simulation ◽  
Ventilation System ◽  
Climatic Conditions ◽  
Temperature Fields ◽  
Poultry House ◽  
Computational Fluid Dynamics Cfd ◽  
Current Lines ◽  
The Impact ◽  
Better Than

Exposure and the outbreak of diseases result in significant losses in large scale poultry operation. New ventilation systems are necessary to provide safe and homogenous internal environment at large enterprises, especially under the changeable climatic conditions of global warming. Within the framework of this investigation, computational fluid dynamics (CFD) simulation of a side ventilation system in a poultry house during winter seasons has been conducted. As results, 3D temperature fields, current lines and pressures in a poultry house have been found. It has been determined that fresh air valves arranged at a height of 200 mm from flooring work better than those traditionally arranged at a height of 400 mm. The erection of walls on the inside of a poultry house framework as well as the decrease in the height of flooring improve poultry house aerodynamics.

scholarly journals Outcomes of COVID-19 Hospitalized Patients Previously Treated with Renin-Angiotensin System Inhibitors

2020 ◽  
Vol 9 (11) ◽  
pp. 3472 ◽  
Author(s):  
Elena-Mihaela Cordeanu ◽  
Lucas Jambert ◽  
Francois Severac ◽  
Hélène Lambach ◽  
Jonathan Tousch ◽  
...  
Keyword(s):  
Renin Angiotensin System ◽  
Severe Pneumonia ◽  
University Hospital ◽  
Angiotensin System ◽  
Angiotensin Converting Enzyme 2 ◽  
Renin Angiotensin ◽  
Previously Treated ◽  
The Impact ◽  
Harmful Effects ◽  
Observation Period

(1) Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) penetrates respiratory epithelium through angiotensin-converting enzyme-2 binding, raising concerns about the potentially harmful effects of renin–angiotensin system inhibitors (RASi) on Human Coronavirus Disease 2019 (COVID-19) evolution. This study aimed to provide insight into the impact of RASi on SARS-CoV-2 outcomes in patients hospitalized for COVID-19. (2) Methods: This was a retrospective analysis of hospitalized adult patients with SARS-CoV-2 infection admitted to a university hospital in France. The observation period ended at hospital discharge. (3) Results: During the study period, 943 COVID-19 patients were admitted to our institution, of whom 772 were included in this analysis. Among them, 431 (55.8%) had previously known hypertension. The median age was 68 (56–79) years. Overall, 220 (28.5%) patients were placed under mechanical ventilation and 173 (22.4%) died. According to previous exposure to RASi, we defined two groups, namely, “RASi” (n = 282) and “RASi-free” (n = 490). Severe pneumonia (defined as leading to death and/or requiring intubation, high-flow nasal oxygen, noninvasive ventilation, and/or oxygen flow at a rate of ≥5 L/min) and death occurred more frequently in RASi-treated patients (64% versus 53% and 29% versus 19%, respectively). However, in a propensity score-matched cohort derived from the overall population, neither death (hazard ratio (HR) 0.93 (95% confidence interval (CI) 0.57–1.50), p = 0.76) nor severe pneumonia (HR 1.03 (95%CI 0.73–1.44), p = 0.85) were associated with RASi therapy. (4) Conclusion: Our study showed no correlation between previous RASi treatment and death or severe COVID-19 pneumonia after adjustment for confounders.

scholarly journals Interdisciplinary and Intercultural Development of an Early Literacy App in Dhuwaya

Languages ◽  
2021 ◽  
Vol 6 (2) ◽  
pp. 106
Author(s):  
Gillian Wigglesworth ◽  
Melanie Wilkinson ◽  
Yalmay Yunupingu ◽  
Robyn Beecham ◽  
Jake Stockley
Keyword(s):  
Phonological Awareness ◽  
Early Literacy ◽  
First Language ◽  
Literacy Skills ◽  
Intercultural Development ◽  
Educational Challenges ◽  
English Speaking ◽  
Surrounding Areas ◽  
Bilingual School ◽  
The Impact

Phonological awareness is a skill which is crucial in learning to read. In this paper, we report on the challenges encountered while developing a digital application (app) for teaching phonological awareness and early literacy skills in Dhuwaya. Dhuwaya is a Yolŋu language variety spoken in Yirrkala and surrounding areas in East Arnhem Land. Dhuwaya is the first language of the children who attend a bilingual school in which Dhuwaya and English are the languages of instruction. Dhuwaya and English have different phonemic inventories and different alphabets. The Dhuwaya alphabet is based on Roman alphabet symbols and has 31 graphemes (compared to 26 in English). The app was designed to teach children how to segment and blend syllables and phonemes and to identify common words as well as suffixes used in the language. However, the development was not straightforward, and the impact of the linguistic, cultural and educational challenges could not have been predicted. Amongst these was the inherent variation in the language, including glottal stops, the pronunciation of stops, the focus on syllables as a decoding strategy for literacy development and challenges of finding one-syllable words such as those initially used with English-speaking children. Another challenge was identifying culturally appropriate images which the children could relate to and which were not copyrighted. In this paper, we discuss these plus a range of other issues that emerged, identifying how these problems were addressed and resolved by the interdisciplinary and intercultural team.

scholarly journals Testing the Effect of Hedge Height on Perceived Safety—A Landscape Design Intervention

2021 ◽  
Vol 13 (9) ◽  
pp. 5063
Author(s):  
Katinka H. Evensen ◽  
Helena Nordh ◽  
Ramzi Hassan ◽  
Aslak Fyhri
Keyword(s):  
Field Study ◽  
Field Experiments ◽  
Landscape Design ◽  
Urban Environments ◽  
Space Management ◽  
Perceived Safety ◽  
Urban Green Spaces ◽  
Outdoor Spaces ◽  
Surrounding Areas ◽  
The Impact

Access to safe, green urban environments is important for quality of life in cities. The objective of this study is to explore the impact of a safety-enhancing landscape design measure on visitors’ experiences in an urban park. Additionally, this paper combines the use of field and virtual reality (VR) experiments, contributing methodological insights into how to evaluate safety measures in green space management and research on perceived safety. In a field experiment (n = 266), we explored whether the height of a hedge along a pathway influenced perceived safety among users. The field study showed that cutting down the hedge improved the perceived prospect of the immediate surrounding areas for female users, which again made them feel safer in the park. We developed a VR experiment for an evening scenario in the same environment (n = 19) to supplement the field study and test the effect of the intervention further. The VR experiment also found a gender effect on perceived safety, with females reporting lower perceived safety, but no effect was shown for the height of the hedge. The results in this study show that environmental attributes such as perceived prospect and concealment should be considered in the design and management of urban green spaces. Additionally, this research demonstrates an approach to conducting field experiments to test the effects of actual design interventions and then further developing these experiments using VR technology. Further research on perceived safety in outdoor spaces is needed to make use of this combined method’s potential.

scholarly journals Impact of the COVID-19 pandemic and its related psychological effect on orthopedic surgeries conducted in different types of hospitals in Taiwan

2021 ◽  
Vol 29 (1) ◽  
pp. 230949902199607 ◽  
Author(s):  
Chia-Lung Shih ◽  
Peng-Ju Huang ◽  
Hsuan-Ti Huang ◽  
Chung-Hwan Chen ◽  
Tien-Ching Lee ◽  
...  
Keyword(s):  
Community Hospital ◽  
University Hospital ◽  
Total Knee Arthroplasties ◽  
Peak Period ◽  
Number Of Patients ◽  
Total Knee ◽  
Investigation Period ◽  
Orthopedic Diseases ◽  
The University ◽  
The Impact

Aim: Taiwan’s response to the coronavirus disease 2019 (COVID-19) differed in that it successfully prevented the spread without having to shutdown or overburden medical services. Patients’ fear regarding the pandemic would be the only reason to reduce surgeries, so Taiwan could be the most suitable place for research on the influence of psychological factors. This study aimed to assess the impact of patients’ fear on orthopedic surgeries in Taiwan amid the peak period of the COVID-19 pandemic. Patients and Methods: The investigation period included the COVID-19 pandemic (March 2020 to April 2020) and the corresponding period in the previous year. The following data on patients with orthopedic diseases were collected: outpatient visits, hospital admission, and surgical modalities. Results: The COVID-19 pandemic led to a 22%–29% and 20%–26% reduction in outpatients, 22%–27% and 25%–37% reduction in admissions, and 26%–35% and 18%–34% reduction in surgeries, respectively, at both hospitals. The weekly mean number of patients was significantly smaller during the COVID-19 pandemic for all types of surgery and elective surgeries at the university hospital, and for all types of surgery, elective surgeries, and total knee arthroplasties at the community hospital. Further, patients visiting the community hospital during the pandemic were significantly younger, for all types of surgery, elective surgeries, and total knee arthroplasties. Conclusions: The reduction in orthopedic surgeries in Taiwan’s hospitals during COVID-19 could be attributed to patients’ fear. Even without restriction, the pandemic inevitably led to a reduction of about 20%–30% of the operation volume.

scholarly journals POS0998 SPONDYLOARTHRITIS AND SLEEP DISORDERS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 767.2-768
Author(s):  
S. Lahrichi ◽  
K. Nassar ◽  
S. Janani
Keyword(s):  
Functional Impairment ◽  
Sleep Disturbances ◽  
Negative Impact ◽  
University Hospital ◽  
Quality Of Sleep ◽  
The Mean ◽  
Sleep Deficit ◽  
Impaired Sleep ◽  
The Impact

Background:Spondyloarthropathies (SpA) are a group of chronic and progressive diseases, characterized in particular by a progressive stiffening of the spine, spreading to neighboring joints or to certain tissues, which could lead in the long term to progressive stiffening and functional impairment. This conditioncancauseinsomnia problems and impaired sleep quality.Objectives:To assess the impact of SpA on the quality of sleep.Methods:This is a retrospective study over a period of 4 years from January 2015 to December 2019, including all the medical records of patients with SpA followed in the Department of Rheumatology of the University Hospital of Ibn Rochd, Casablanca. We evaluated for each patient two validated scores: the Epworth somnolence scale rated from 0 to 24, and the Pittsburgh sleep score rated from 0 to 21 with 7 components. Patients with a psychiatric history or who were followed up for neurological pathologies were excluded.Results:178 patients were included. 60.67% were men with an average age of 36.32 years (14-68 years). 45.01% had axial SpA, 29.77% had psoriatic arthritis, and 25.22% were followed for SpA associated with inflammatory bowel disease. 45% had associated comorbidities: there were 18 diabetics and 34 hypertensive, 16.58% were smokers. Clinically, 85.42% presented a back pain initially on examination, 55% presented a polyarthralgia, and 39.88% an oligoarthritis. 63% had radiological sacroiliitis, and 35.14% had bilateral coxitis. 13.48% had a positive HLA B27 and 58.89% had a positive inflammatory assessment with very high activity indices,with a mean of 4.6. 64.66% of the patients received NSAIDs,of which 11% responded well. 57% were treated with csDMARDs, and 17.86% were treated with biologics. At the time of our study, the mean visual analog scale was 5.84 ± 1.7 out of 10 (2-9). The mean Epworth score was 8.38 ± 5.2 (0-21). 56.1% of patients had no sleep debt, 33.3% had a sleep deficit, and only 10.6% had signs of drowsiness. For the overall Pittsburgh score, the mean was 7.02 ± 3.6 (1-18). The mean of “subjective quality of sleep” was 1.12, “sleep latency” was 1.22, “duration of sleep” was 1.06, “usual sleep efficiency” was 0.74, “Sleep disturbance” of 1.28, “use of a sleep medication” of 0.54, and the average of the component concerning “poor shape during the day” was 1.03 out of 3. The LEQUESNE index went from an average of 6 to 8, which corresponds to an average handicap (P = 0.2) over a period of 3 years. 68% of the patients had an alteration in the quality of sleep, starting on average three years after the onset of symptoms. 11% reported having experiencedanxiety and depressive symptoms, and reported having used antidepressants or anxiolytics in the past 5 years.Conclusion:Our study showed the negative impact of SpA on the duration and overall quality of sleep. The degree of pain as well as functional impairment can cause and worsen sleep disturbances in SpA. We have shown that the Pittsburg score increases significantly with the increase of pain.The Lequesne score and that the Epworth score increase with disease activity[1].References:[1]StolwijkC,vanTubergenA,Castillo-OrtizJD,BoonenA.Prevalenceofextra-articularmanifestationsinpatientswithankylosingspondylitis:asystematicreviewandmeta-analysis.AnnRheumDis2015;74:65—73.Disclosure of Interests:None declared.

scholarly journals Impact of Cardiovascular Failure in Intensive CareUnit-Acquired Pneumonia: A Single-Center, Prospective Study

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 798
Author(s):  
Ignacio Martin-Loeches ◽  
Adrian Ceccato ◽  
Marco Carbonara ◽  
Gianluigi li Bassi ◽  
Pierluigi di Natale ◽  
...  
Keyword(s):  
Cox Regression ◽  
University Hospital ◽  
Single Center ◽  
Cox Regression Analysis ◽  
Cardiovascular Failure ◽  
Icu Length Of Stay ◽  
Patients At Risk ◽  
Surgical Icus ◽  
Pulmonary Superinfection ◽  
The Impact

Background: Cardiovascular failure (CVF) may complicate intensive care unit-acquired pneumonia (ICUAP) and radically alters the empirical treatment of this condition. The aim of this study was to determine the impact of CVF on outcome in patients with ICUAP. Methods: A prospective, single-center, observational study was conducted in six medical and surgical ICUs at a University Hospital. CVS was defined as a score of 3 or more on the cardiovascular component of the Sequential Organ Failure Assessment (SOFA) score. At the onset of ICUAP, CVF was reported as absent, transient (if lasting ≤ 3 days) or persistent (>3 days). The primary outcome was 90-day mortality modelled through a Cox regression analysis. Secondary outcomes were 28-day mortality, hospital mortality, ICU length of stay (LOS) and hospital LOS. Results: 358 patients were enrolled: 203 (57%) without CVF, 82 (23%) with transient CVF, and 73 (20%) with persistent CVF. Patients with transient and persistent CVF were more severely ill and presented higher inflammatory response than those without CVF. Despite having similar severity and aetiology, the persistent CVF group more frequently received inadequate initial antibiotic treatment and presented more treatment failures than the transient CVF group. In the persistent CVF group, at day 3, a bacterial superinfection was more frequently detected. The 90-day mortality was significantly higher in the persistent CVF group (62%). The 28-day mortality rates for patients without CVF, with transient and with persistent CVF were 19, 35 and 41% respectively and ICU mortality was 60, 38 and 19% respectively. In the multivariate analysis chronic pulmonary conditions, lack of Pa02/FiO2 improvement at day 3, pulmonary superinfection at day 3 and persistent CVF were independently associated with 90-day mortality in ICUAP patients. Conclusions: Persistent CVF has a significant impact on the outcome of patients with ICUAP. Patients at risk from persistent CVF should be promptly recognized to optimize treatment and outcomes.

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