The Use of Virtual Reality For Student Training on Bias And Microaggressions

Virtual reality (VR) is an immersive innovative technology that can be used with occupational therapy students for bias training in preparation for fieldwork and clinical practice. The purpose of this study was to explore the use of VR as a complementary educational tool in bias and microaggressions (MA) training for entry-level occupational therapy students. We conducted a secondary analysis of data collected in an 8-week course on diversity, equity, inclusion, and professional skills with a total of 48 first-year entry-level occupational therapy students. We used eight simulated VR cases for all students. Data was collected using a mixed-method survey to capture the students’ experiences with VR. The results showed that the majority of students found the VR module helpful in identifying bias and MA (n=47; 97.92%), enhancing their confidence to report bias and MA (n=48; 100%), offering opportunities to respond to bias and MA (n=39; 81.25%), and articulating why certain behaviors can be perceived as MA (n=45; 93.75%). Thematic analysis of qualitative data showed that the VR enhanced students’ ability to detect bias and MA, and increased the sense of empathy, and ability to be an ally or advocate for targets of bias. The findings indicate that VR is an immersive, engaging technology that can be used for bias and MA training for students and potentially clinicians. It offers a private, inclusive, pressure-reduced learning space for students to learn about bias and MA in preparation for fieldwork education and clinical practice

Sandstone matrix acidizing knowledge and future development

To meet rising global demands for energy, the oil and gas industry continuously strives to develop innovative oilfield technologies. With the development of new enhanced oil recovery techniques, sandstone acidizing has been significantly developed to contribute to the petroleum industry. Different acid combinations have been applied to the formation, which result in minimizing the near wellbore damage and improving the well productivity. A combination of hydrofluoric acid and hydrochloric acid (HF:HCl) known as mud acid has gained attractiveness in improving the porosity and permeability of the reservoir formation. However, high-temperature matrix acidizing is now growing since most of the wells nowadays become deeper and hotter temperature reservoirs, with a temperature higher than 200 °F. As a result, mud acid becomes corrosive, forms precipitates and reacts rapidly, which causes early consumption of acid, hence becoming less efficient due to high pH value. However, different acids have been developed to combat these problems where studies on retarded mud acids, organic-HF acids, emulsified acids, chelating agents have shown their effectiveness at different conditions. These acids proved to be alternative to mud acid in sandstone acidizing, but the reaction mechanism and experimental analysis have not yet been investigated. The paper critically reviews the sandstone acidizing mechanism with different acids, problems occurred during the application of different acids and explores the reasons when matrix stimulation is successful over fracturing. This paper also explores the future developing requirement for matrix acidizing treatments and new experimental techniques that can be useful for further development, particularly in developing new acids and acidizing techniques, which would provide better results and information of topology, morphology and mineral dissolution and the challenges associated with implementing these “new” technologies

Flowback cleanup mechanisms of post-hydraulic fracturing in unconventional natural gas reservoirs

This work investigates the fracturing fluid cleanup mechanisms of post-hydraulic fracturing in unconventional gas formations by studying a large number of wide-ranging parameters simultaneously. In this work, different scenarios of the cleanup operation of the hydraulic fracturing process are considered. This study consists of investigating the post-fracturing cleanup operation of hydraulically fractured vertical wells (VW) and multiple fractured horizontal wells (MFHWs). Additionally, the impact of soaking time, the range of the matrix permeability, applied drawdown pressure, injected fracturing fluid (FF) volume, fracture spacing and horizontal well length has been investigated by running different sets. Results show that that the trend of the impact of relevant parameters for VWs and MFHWs are analogous excepting the matrix permeability, km. That is, in the MFHW base reference set, the effect of matrix permeability on capillary pressure is more significant than that on fluid flow while the reverse is observed for VW. The difference in the impact of km in VWs and MFHWs is attributed to the geometry of the fluid flow towards the production well and different well completion scheme. It is also concluded that the impact of parameters affecting the capillary pressure in the matrix is more significant for MFHWs whereas matrix and fracture mobility pertinent parameters are more important for VWs than MFHWs. As a result, larger matrix capillary pressure values are more vital in the cleanup of MFHWs because of more imbibition of FF into the matrix and subsequently lower conflict between the flow of gas and FF in the fracture. The other part of this research concentrates on the impact of IFT reducing agents on the post-fracturing production in different formations. In hydraulic fracturing operations, these agents are commonly used as an additive in fracturing fluid to facilitate its backflow by reducing Pc and subsequently enhancing gas production. The results of this work recommend that using such agents enhances the gas production rate for ultratight formations but not for tight formations (it reduces the gas production rate). Therefore it is not suggested to use such agents in tight formations. The findings of this work improve the understanding of fracture cleanup leading to better design of hydraulic fracturing operations in unconventional formations

Ring-Exchange Interaction Effects on Magnons in Dirac Magnet CoTiO3_3

In magnetically ordered materials with localized electrons, the fundamental magnetic interactions are due to exchange of electrons [1-3]. Typically, only the interaction between pairs of electrons' spins is considered to explain the nature of the ground state and its excitations, whereas three-, four-, and six-spin interactions are ignored. When these higher order processes occur in a loop they are called cyclic or ring exchange. The ring-exchange interaction is required to explain low temperature behavior in bulk and thin films of solid $^3$He [4-8]. It also plays a crucial role in the quantum magnet La$_2$CuO$_4$ [9,10]. Here, we use a combination of time domain THz (TDTS) and magneto-Raman spectroscopies to measure the low energy magnetic excitations in CoTiO$_3$, a proposed Dirac topological magnon material [11,12] where the origin of the energy gap in the magnon spectrum at the Brillouin zone center remains unclear. We measured the magnetic field dependence of the energies of the two lowest energy magnons and determine that the gap opens due to the ring-exchange interaction between the six spins in a hexagon. This interaction also explains the selection rules of the THz magnon absorption. Finally, we clarify that topological surface magnons are not expected in CoTiO$_3$. Our study demonstrates the power of combining TDTS and Raman spectroscopies with theory to identify the microscopic origins of the magnetic excitations in quantum magnets.Comment: 7 pages, 4 figures in main text, 26 pages and 11 figures in supplemen

Kinetics of Tertiary Reaction of HF on Alumino-Silicates

Abstract The standard description of HF acidizing chemistry clearly demonstrates a primary and secondary reaction of HF with alumino-silicates.1 Field experience has taught our industry that possible precipitation during the secondary reaction can adversely affect treatment success.2 This statement has been particularly true in formations with high K-feldspar content or formations having temperatures above 300°F. Recent work has also reported the existence of a third, or tertiary reaction of HF with alumino-silicates.3 This paper reports how the rate law and kinetics for this tertiary reaction are determined on kaolinite and feldspar over a broad temperature range. This document also discusses the discovery of how most clays were thermally unstable to HC1 at temperatures above 250°F. These findings were made possible by recently applied experimental techniques including l9FNMR Spectroscopy,3 fractional pore volume flow experiments,4 and an accurate knowledge of the HF stoichiometry.5 The tertiary reaction of aluminum fluorides, AlFx (where x is the average F/Al ratio), with clay was slow below 200°F and was dominated by HC1 decomposition of the clay above 250°F. The tertiary reaction required the presence and consumption of acid to proceed. Feldspars were very stable in HC1 at all temperatures while every clay tested had a temperature above which it was easily decomposed by HC1. Ion-exchanging clays tended to be the least stable of the clays, while kaolinite was the most stable clay.</jats:p

Recent Advances in Carbonate Stimulation

Abstract Carbonate acidizing continues to be a vital process for improving the production of oil and gas wells. Laboratory studies and field evaluations of carbonate acidizing during the past 30 years have shown a continually improved understanding of the fundamental issues. This paper discusses the current state of the advances in carbonate stimulation. Average reactivity data for several limestones and dolomites are presented and can be used as improved default values for simulators. Wormhole development and structure during matrix acidizing are viewed as symmetry dominated processes controlled by fluid flow that obeys the native permeability contrasts within the matrix. The resulting simplification allows for rational treatment designs for matrix acidizing of carbonates. Zonal coverage of long carbonate sections, whether vertical or horizontal, remains a challenge. However, using the "75–25" rule for horizontal wells, creating a "thief zone" at the bottom or toe of the well, and utilizing the "top decade of permeability" rule can aid in achieving reasonable designs for maximizing productivity. The three fundamental issues of fracture acidizing are addressed: reactivity control, fluid loss control, and conductivity generation. Because synthetic polymers for acid gellants have made reactivity control easy, fluid loss control is usually the most dominant issue to be addressed in fracture acidizing. Carbonate Reactivity Several models are available to predict the spending of acid on carbonates. Some calculate the spending during fracture acidizing while some calculate the spending during matrix acidizing and wormhole generation. The earliest spending tests were simple spending time experiments in open beakers. However, it soon became clear that this was an inadequate procedure because mass transport definitely plays a role. Experiments conducted on quarried limestone and dolomite during the 1970s gave our first estimates of the temperature dependence of the reactivity of HCl on carbonates. These experiments suggested that limestones had incredibly high reactivity with acid such that one could assume a mass transport limited process. </jats:sec

Applying asynchronous transfer mode to the Marine Corps Base level information infrastructure

This thesis reports the findings of a simulation comparing network architecture configurations in terms of interactions and performance in the face of varying traffic demand. It models the U. S. Marine Corps Base Level Information Infrastructure using a top-down approach. Extend(R) queuing theory modeling software was used to decompose the network model with a bottom-up approach to testing and integration. Feasible network configurations were identified and modeled under varying load parameters. Asynchronous Transfer Mode was found to be suited as a distribution protocol at the infrastructure levels of backbone and area distribution node. Fast Ethernet and Ethernet were found to be 0 optimal at lower levels of infrastructure. Network design recommendations are made for network engineers.http://archive.org/details/applyingsynchron1094513505U.S. Marine Corps (U.S.M.C.) author.Approved for public release; distribution is unlimited

Surfactant Modeling for Insight into Load-Recovery Enhancement for Fracturing Treatments

Abstract Load recovery from fracturing treatments in tight-gas sands is often considered to be an important indicator of success. Poor load recovery is often associated with poor performance, and used to invoke water blocks as a damage mechanism. Surfactants are designed and used to enhance load recovery, presumably by capillary pressure effects. A fit-for-purpose fracture cleanup and chemistry simulator (FCCS) was improved to study the impact of surfactant adsorption, surface-wettability changes, and surface-tension reduction on load recovery from hypothetical fracturing treatments. The simulator was improved by adding surfactant adsorption/desorption kinetics, wettability functions that were dependant on the amount of adsorption, and adsorption capacities. Simulations were conducted as a function of fracture conductivity, matrix relative permeability (rel-perm) quality, and various surfactant properties. It was found that surfactants have the greatest impact when matrix rel-perm functions are of moderately good quality or better. Surface-tension reduction alone tended to simply enhance imbibition, while changing wettability to near non-wet substantially enhanced load recovery. Fracture conductivity had a substantial role because it determined whether imbibition or drawdown won the battle over water movement. The methodology of the surfactant modeling is presented, along with the results from numerous simulations. This work demonstrates that surfactants can enhance load recovery under certain circumstances, with wettability changes being most important. However, matrix rel-perms must be of sufficient quality that capillary effects are able to overcome viscous effects.</jats:p