No abstract

To safely plan and execute MPD Influx Control operations, the limits of the primary barrier envelope must be communicated and understood. These safe operating limits have historically been represented with an MPD Operations Matrix. More recently, the development of the Influx Management Envelope (IME) has provided a means of communicating the primary barrier limits with improved accuracy and clarity. However, the generation of the IME currently requires performing a series of complex well control simulations with specialist engineering support. Because drilling operations are dynamic in nature, a practical method to generate the IME boundaries at the wellsite is required so that changes to mud weight, flowrate, surface and bottom hole circulating temperatures, trajectory, and bit depth can be accounted for, and the IME kept up to date. This paper describes the development of a novel tool to quickly and automatically generate IMEs at the wellsite without the need for sophisticated modelling software and specialist personnel. The single bubble derivation that was originally presented by Culen et al was analysed further to obtain a more accurate and explicit relationship rather than an implicit one, which forms the basis for the calculations. The IME can be updated based on any well parameter changes, which allows field engineers to maintain an up to date and accurate IME throughout MPD operations.

A new technique for investigation of the electrical effects of micropipes in single-crystal 6H-SiC is presented. The setup allows the application of a parallel or normal electric field to MSM (metal-semiconductor-metal) test structures and the visualization of light emission sites in the test gap, including light activity underneath the metal contact. A special transparent metal [indium-tin-oxide(ITO)] was chosen for the metallic contacts. A map of micropipe locations was initially obtained at zero applied field using a laser scattering method. The initial map is compared with that of light emissions at different applied fields.Several tests on undoped and vanadium-doped (compensated) SiC, using NiCr/Au or ITO contacts, indicated the rapid activation of micropipes at relatively low fields in vertical MSM devices. A good match between the laser imaging map of micropipes at zero field and the map of field-induced light emission sites indicates that micropipes are the main current paths in vertical devices, carrying a large current density, and leading to light emissions and partial or total bulk breakdown of the test device.

Background: The COVID-19 pandemic is creating major issues for healthcare and broad social structures, exposing societal vulnerabilities. Patients with substance use disorder are considered at increased risk of COVID-19 and its more serious complications, however data on the impact of COVID-19 are lacking. The study aimed to describe the clinical characteristics and outcomes of COVID-19 on patients with substance use disorders seen at Kuwait addiction treatment center. Method: A cross sectional study was carried including all patients seen in outpatient department and/or admitted in the inpatient wards of Kuwait Addiction Treatment Center, diagnosed as substance use disorder with history of COVID-19 infection during the period from June 2021 to December 2021. Results : Among 660 substance use disorder patients, the mean age was 36± 10.1 years (94%) were men and (91.1%) were Kuwaiti. The main substance used were Opioid in (41.1%) of patients, stimulant in (25.5%) and synthetics in (11.2%) of patients. One or more comorbidities associated to COVID-19 risk were observed in (29 %) of patients. (9.1%) of patients got COVID-19 infection and 61.5% were vaccinated.