potential pressure
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2021 ◽  
Author(s):  
Aurelio Marcano Avila ◽  
Abimbola Raji ◽  
Renny Ottolina ◽  
Jose Jimenez

Abstract In the UAE, an Operator needed to perform a completion change out in a gas well, where the existing completion has been installed for over 30 years. Logging operations had revealed several leaks point in the production tubing due to corrosion. To rectify the situation, a Hydraulic Workover (HWO) Unit was proposed integrating a punch ram in the Blowout Preventer (BOP) Configuration to manage the bleed off of potential pressure trapped between the isolated sections of the completion at surface. This document describes how the highly corroded completion tubing with eleven retrievable plugs set in a live gas well was recovered. The HWO Unit was modified so that one of the cavities in the BOP stack was dressed with customized punch rams for five inch pipe, with the objective of allowing control of any potential leaks due to plug failure. The pressure relief operation could then be completed by means of punching the tubing in the controlled environment that a Stripping BOP Stack provides. This paper compiles the details of the BOP configuration and operating procedures to recover the completion by stripping out of the well and operating the punch rams with the snubbing unit. This includes the pre-job preparation required for a successful operation and the overall design with where to locate the collars and plugs for an accurate punch, and how to confirm that the plugs are holding the pressure to continue retrieving the next completion section. In the end, a safe operation was completed with zero incidents or down time allowing the intervention to continue to the next stage of recompleting the well and putting it back to production. The customer was able to get the well back to production with an alternative solution to what was initially considered, representing a significant cost and time saving.


2021 ◽  
Vol 34 (4) ◽  
pp. 591-595
Author(s):  
Wei Fan

Because charge, current, resistance, and voltage are understood based on the perspective of electricity, they can describe various electrical phenomena well, but they cannot explain their origins. Therefore, this article attempts to propose a new understanding of these phenomena from the perspective of mechanics to obtain a feasible way of explaining their origin and to solve problems that cannot be explained from the perspective of electricity. Specifically, this paper attempts to explain the origin of electric charge to obtain a new understanding of the origin of current and to obtain a new understanding of voltage and resistance by explaining the origin of current. Finally, from the perspective of mechanics, the origin of charge can be understood as a manifestation of electron momentum, the origin of current can be understood as a momentum flow, the origin of resistance can be understood as a momentum resistance, and the origin of voltage can be understood as a potential pressure (potential difference) of electron orbital potential. This new understanding of the origin of current from a mechanical perspective can provide a new theoretical explanation for high-temperature superconductivity.


2021 ◽  
pp. 17-30
Author(s):  
Charles Becht

Design conditions in ASME B31.3 are specifically intended for pressure design. The design pressure and temperature are the most severe coincident conditions, defined as the conditions that result in the greatest pipe wall thickness or highest required pressure class or other component rating. Design conditions are not intended to be a combination of the highest potential pressure and the highest potential temperature, unless such conditions occur at the same time.


2021 ◽  
Vol 10 (3) ◽  
pp. 0-0

The packaging industry has considerably been witnessing significant growth over the past few years. In today’s scenario, incorporating sustainable practices in packaging businesses is becoming a standard. Whether, it is due to the preferences of manufacturers, regulatory standards, consumer pressure, or retailer’s choice, the eco-friendly packaging solutions are increasingly attaining a rise in demand. Shifting trend towards environmental efficiency, has led to an increase in focus on fewer resources, lesser energy as well as smaller footprint among various packaging businesses. In order to cater to the potential pressure stemming from these trends, advanced level of agility and technological innovation is gaining traction. Hence, re-inventing and re-thinking by packaging industries poses strong and concrete opportunities for the transformational shift towards sustainability solutions thereby, also eliminating the plastic packaging issues in different sectors. This paper discusses about the determinants impacting sustainable packaging along with the market analysis for the same.


Author(s):  
Gui-Qing Xu ◽  
Xiao-Jun Mi ◽  
Jian Ma ◽  
Jie Ma ◽  
Lisong Tang

Anthropogenic withdraw of groundwater and climatic drought results in the decline of groundwater depth that, in turn, severely limits the water availability for phreatophytic vegetation in arid regions. In this study, a small xeric, phreatophytic tree Haloxylon ammodendron (C.A. Mey.) was investigated to understand the influence of depth to groundwater (DGW) on hydraulic traits and on the trade-off between drought tolerance and leaf area increment. A suite of traits including leaf water potential, pressure–volume (P–V) curves, Huber value, assimilation branch growth, and osmotic regulation substance were measured across five sites with DGW ranges from 3.45 to 15.91 m. Our results indicate that H. ammodendron was subject to greater water stress with increasing DGW, as indicated by decreased predawn (Ψpd) & midday (Ψmd) branch water potential. We also found that growth rate declined as Huber value increased with increasing DGW in the early growing season (EGS). Solute sugar, as a major osmotic substance, drives decreases in osmotic potential at full turgor, and thus constrains assimilation branch growth with increasing DGW in EGS. Therefore, osmotic adjustment accompanied with water potential regulation (Ψpd-Ψmd) and plasticity of Huber value allows this phreatophyte to absorb water from deeper soil layers and tolerate drought. However, these adaptive adjustments cannot fully compensate for nonoptimal water conditions as growth rate continued to decrease as DGW increased in EGS and even became negative in the late growing season (LGS) at almost all sites. Our results provide an insight into how H. ammodendron responds and adapts to changes DGW in a region experiencing hydrological and climatic drought. Greater depth of groundwater had a significant effect on H. ammodendron and may have similar effects for other non-riparian phreatophytic plants in arid regions.


2021 ◽  
Author(s):  
Wei Fan

Abstract This article attempts to provide a feasible understanding of electromagnetics from the perspective of mechanics. Among them, from the perspective of mechanics, charge can be understood as a form of electron momentum; electric current can be understood as a momentum flow; resistance can be understood as a momentum resistance of electrons; voltage can be interpreted as the potential pressure or energy level difference of the electron orbital potential; the electric field can be understood as a manifestation of the magnetic field of the current element. Finally, this article proposes a new understanding of some basic concepts of electromagnetics from the perspective of mechanics.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Julie Allard ◽  
Fabian Ballesteros ◽  
Marie-Chantal Fortin

Abstract Background Medical assistance in dying (MAID) has been legal in Québec since December 2015 and in the rest of Canada since July 2016. Since then, more than 60 people have donated their organs after MAID. Such donations raise ethical issues about respect of patients’ autonomy, potential pressure to choose MAID, the information given to potential donors, the acceptability of directed donations in such a context and the possibility of death by donation. The objective of this study was to explore Québec professionals’ perspectives on the ethical issues related to organ donation after MAID. Methods We conducted semi-directed interviews with 21 health care professionals involved in organ donation such as intensivists and intensive care nurses, operating room nurses, organ donation nurses and coordinators. Results The participants were all favourable to organ donation after MAID in order to respect patients’ autonomy. They also favoured informing all potential donors of the possibility of donating organs. They highlighted the importance of assessing donors’ reasons for requesting MAID during the assessment. They were divided on directed donation, living donation before MAID and death by donation. Conclusion Organ donation after MAID was widely accepted among the participants, based on the principle of respect for the donor’s autonomy. The findings of this study only provide the perspectives of Québec health care professionals involved in organ donation. Future studies are needed to gather other stakeholders’ perspectives on this issue as well as patients’ and families’ experiences of organ donation after MAID.


Author(s):  
Nick Shryane ◽  
Maria Pampaka ◽  
Andrea Lisette Aparicio Castro ◽  
Shazaad Ahmad ◽  
Mark Elliot ◽  
...  

IntroductionLength of Stay (LoS) in Intensive Care Units (ICUs) is an important measure for planning beds capacity during the Covid-19 pandemic. However, as the pandemic progresses and we learn more about the disease, treatment and subsequent LoS in ICU may change. ObjectivesTo investigate the LoS in ICUs in England associated with Covid-19, correcting for censoring, and to evaluate the effect of known predictors of Covid-19 outcomes on ICU LoS. Data sourcesWe used retrospective data on Covid-19 patients, admitted to ICU between 6 March and 24 May, from the “Covid-19 Hospitalisation in England Surveillance System” (CHESS) database, collected daily from England’s National Health Service, and collated by Public Health England. MethodsWe used Accelerated Failure Time survival models with Weibull and log-normal distributional assumptions to investigate the effect of predictors, which are known to be associated with poor Covid-19 outcomes, on the LoS in ICU. ResultsPatients admitted before 25 March had significantly longer LoS in ICU (mean = 18.4 days, median = 12), controlling for age, sex, whether the patient received Extracorporeal Membrane Oxygenation, and a co-morbid risk factors score, compared with the period after 7 April (mean = 15.4, median = 10). The periods of admission reflected the changes in the ICU admission policy in England. Patients aged 50-65 had the longest LoS, while higher co-morbid risk factors score led to shorter LoS. Sex and ethnicity were not associated with ICU LoS. ConclusionsThe skew of the predicted LoS suggests that a mean LoS, as compared with median, might be better suited as a measure used to assess and plan ICU beds capacity. This is important for the ongoing second and any future waves of Covid-19 cases and potential pressure on the ICU resources. Also, changes in the ICU admission policy are likely to be confounded with improvements in clinical knowledge of Covid-19.


2021 ◽  
Author(s):  
Wei Fan

Abstract This article attempts to provide a new analogy understanding of some conceptual foundations of electromagnetics from the perspective of mechanics to satisfy childhood curiosity. Among them, from the perspective of mechanics, charge can be understood as a form of electron momentum; electric current can be understood as a momentum flow; resistance can be understood as a momentum resistance of electrons; voltage can be interpreted as the potential pressure or energy level difference of the electron orbital potential; the electric field can be understood as a manifestation of the magnetic field of the current element.


2020 ◽  
Author(s):  
Irena Papst ◽  
Michael Li ◽  
David Champredon ◽  
Benjamin Bolker ◽  
Jonathan Dushoff ◽  
...  

Abstract Background: Patient age is the most salient clinical indicator of risk from COVID-19. Age-specific distributions of known SARS-CoV-2 infections and COVID-19-related deaths are available for many regions. Less attention has been given to the age distributions of serious medical interventions administered to COVID-19 patients, which could reveal sources of potential pressure on the healthcare system should SARS-CoV-2 prevalence increase. Methods: We analysed 97,957 known SARS-CoV-2 infection records for Ontario, Canada, from 23 January 2020 to 26 November 2020 and estimated the age distributions of hospitalizations, Intensive Care Unit admissions, intubations, and ventilations. We quantified the probability of hospitalization given known SARS-CoV-2 infection, and of survival given COVID-19-related hospitalization. Results: The distribution of hospitalizations peaks with a wide plateau covering ages 54–90, whereas deaths are concentrated in very old ages. The estimated probability of hospitalization given known infection reaches a maximum of 30.9% at age 80 (95% CI 28.0%–33.9%). The probability of survival given hospitalization is near 100% for adults younger than 40, but declines substantially after this age; for example, a hospitalized 54-year-old patient has a 91.5% chance of surviving COVID-19 (95% CI 87.0%–94.9%). Conclusions: Ontario’s healthcare system has not been overstretched by COVID-19 thanks to wide-spread infection control efforts, yet the probability of survival given hospitalization for COVID-19 is lower than is generally perceived for patients over 40. As pervalence continues to increase during this most recent wave of infection, healthcare capacities are at risk of being exceeded. Survival of individuals in the broad age range requiring acute care could decrease, potentially expanding the distribution of COVID-19-related deaths toward younger ages.


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