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Using fracture-based continuum modeling of coupled geomechanical-hydrological processes for numerical simulation of hydraulic fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1582-1599页

作者： Goodluck I.Ofoegbu GNO Modeling Research llc. San AntonioTX78253USA

This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fracture *** simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBCM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(*** re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain *** simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density *** combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing *** are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tensorial aggregation of the behavior of discrete fractures and unfractured *** are presented for previously unfractured rock and for rock with preexisting fractures of horizontal,shallow-dipping,steeply dipping,or vertical *** of a single-well model are used to determine the pattern and spacing for a multiple-well *** results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or horizontal fractures,and in situ vertical compressive stress greater than *** preexisting fractures are steeply dipping or vertical,and considering the same in situ

关键词： Discrete fracture Fracture-based continuum modeling Fracture caging High-density fracturing Hydraulic fracturing Preexisting fracture

Kriging-boosted CR modeling for prompt infill drilling optimization

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Petroleum 2024年第1期10卷 39-48页

作者： Elizaveta S.Gladchenko Anna E.Gubanova Denis M.Orlov Dmitry A.Koroteev Skolkovo Institute of Science and Technology Russian Federation Digital Petroleum llc Russian Federation

The capacitance-resistance model(CRM) has been a useful physics-based tool for obtaining production forecasts for decades. However, the model's limitations make it difficult to work with real field cases,where a lot of various events happen. Such events often include new well commissioning(NWC). We introduce a workflow that combines CRM concepts and kriging into a single tool to handle these types of events during history matching. Moreover, it can be used for selecting a new well placement during infill drilling. To make the workflow even more versatile, an improved version of CRM was used. It takes into account wells shut-ins and performed workovers by additional adjustment of the model coefficients. By preliminary re-weighing and interpolating these coefficients using kriging, the coefficients for potential wells can be determined. The approach was validated using both synthetic and real datasets, from which the cases of putting new wells into operation were selected. The workflow allows a fast assessment of future well performance with a minimal set of reservoir data. This way, a lot of well placement scenarios can be considered, and the best ones could be chosen for more detailed studies.

关键词： Capacitance-resistance model (CRM) Field development optimization Infill drilling Interwell connectivity Kriging New well commissioning (NWC)

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Artificial light at night(ALAN) pollution alters bat lunar chronobiology:insights from broad-scale long-term acoustic monitoring

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Ecological Processes 2024年第01期13卷 176-187页

作者： Han Li Pauline Allen Saige Boris Samantha Lagrama Jade Lyons Christina Mills Pauline Moussi Casey Nichols Carter Tacosik Mc Kenzie Tsaousis Nyzaya Livingston Wilson John F.Grider Kevin A.Parker Matina C.Kalcounis-Rueppell Department of Biology University of Nebraska Omaha Department of Biology University of North Carolina Greensboro Colorado Parks and Wild-life Parker Ecology llc Department of Biological Sciences University of Alberta

Background The timing of behavior and habitat use of nocturnal animals can be influenced by the lunar cycle in nature. The prevalence of artificial light at night(ALAN) has been recognized as a source of environmental pol-lution. The interaction between ALAN and the lunar cycle on bat behavior is important for understanding anthro-pogenic effects on bats. We utilized a decade(2012–2022) of acoustic monitoring data collected in North Carolina, United States, to investigate the relationship between bat activity, lunar cycle, and light pollution. We examined whether the amount of lunar illumination affected species-specific nightly activity and whether hourly bat activity patterns varied between nights with different moon phases. We further investigated if the relationship between bat activity and the lunar cycle might be altered by light *** We found that seven bat species showed activity variation across nights in relation to the amount of moon illumination when ALAN was absent. In general, bats were less active on full moon nights compared to new moon nights. Light pollution interacted with the bat–lunar relationship in five of the seven species, masking the effect of the lunar cycle. We identified delayed bat activity patterns on nights with a full or waxing moon in seven species, and light pollution altered that pattern in four species. Overall, ALAN was associated with decreased bat activity inde-pendent of lunar cycle *** Our study demonstrated that at a broad spatial scale, ALAN negatively affected many North American temperate bat species and altered their lunar chronobiology. As light pollution is spreading to historically dark areas and habitats, ALAN might couple with other threats, such as the white-nose syndrome or climate change, to cause cascading damage in the environment that depends on ecosystem services such as pest control provided by bats. We argue that further research and conservation actions are needed to mitigate

关键词： Artificial light at night ALAN Bats Chiroptera Chronobiology Light pollution Lunar cycle Moonlight

Self-powered UVC detectors based on α-Ga_(2)O_(3) with enchanted speed performance

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Journal of Semiconductors 2024年第8期45卷 74-80页

作者： Aleksei Almaev Alexander Tsymbalov Bogdan Kushnarev Vladimir Nikolaev Alexei Pechnikov Mikhail Scheglov Andrei Chikiryaka Laboratory of Metal Oxide Semiconductors Research and Development Center for Advanced Technologies in MicroelectronicsNational Research Tomsk State UniversityTomsk 634050Russia Fokon llc Kaluga 248035Russia Department of Semiconductor Electronics and Physics of Semiconductors National University of Science and Technology MISISMoscow 119049Russia Perfect Crystals llc Saint Petersburg 194223Russia

Detectors were developed for detecting irradiation in the short-wavelength ultraviolet(UVC)interval using high-quality single-crystallineα-Ga_(2)O_(3) films with Pt interdigital *** films ofα-Ga_(2)O_(3) were grown on planar sapphire substrates with c-plane orientation using halide vapor phase *** spectral dependencies of the photo to dark current ratio,responsivity,external quantum efficiency and detectivity of the structures were investigated in the wavelength interval of 200−370 *** maximum of photo to dark current ratio,responsivity,external quantum efficiency,and detectivity of the structures were 1.16×10^(4) ***.,30.6 A/W,1.65×10^(4)%,and 6.95×10^(15) Hz^(0.5)·cm/W at a wavelength of 230 nm and an applied voltage of 1 *** high values of photoelectric properties were due to the internal enhancement of the photoresponse associated with strong hole ***α-Ga_(2)O_(3) film-based UVC detectors can function in self-powered operation mode due to the built-in electric field at the Pt/α-Ga_(2)O_(3) *** a wavelength of 254 nm and zero applied voltage,the structures exhibit a responsivity of 0.13 mA/W and an external quantum efficiency of 6.2×10^(−2)%.The UVC detectors based on theα-Ga_(2)O_(3) films demonstrate high-speed performance with a rise time of 18 ms in self-powered mode.

关键词： HVPE gallium oxide solar-blind ultraviolet detector self-powered mode

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SARS-CoV-2 Pooled Testing Methodology for PCR Testing Applied in Private Laboratory in Armenia

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Advances in Infectious Diseases 2024年第1期14卷 67-73页

作者： Inessa Nazaryan Narek Pepanyan Arshag Keshishyan Susanna Petrosyan Naira Margaryan Shahane Mnatsakanyan EcoSence llc Yerevan Armenia

Since the beginning of COVID-19 pandemics many countries were facing challenges with testing capacity recourse limitations. Throughout the waves of the pandemic countries were trying to address the existing constrains exploring solutions to increase the testing capacity with more cost-effective approaches. Pooled methodology was one of the methods which many have validated and used. It is evident that in case of pooled sample testing the sensitivity becomes lower, however the variation highly depends on the pool size as well as the incidence rate at the certain point. Armenia as well as many other countries has adopted regulations for mandatory COVID-19 PCR testing for all the travelers. Current study aimed to explore the efficiency of COVID-19 pooled PCR testing for nasopharyngeal swabs of individuals with no symptoms in a time period with good epidemiological state of the infection. Nasopharingeal swab samples from individuals were collected. The manual extraction of RNAs of samples was performed after pooling up to 5 samples. The pools with Cycle Threshold (CT) of < 37 were considered positive and were retested individually. In total 28,015 samples were grouped in 667 pools of which 57 were positive. The total number of positive samples was 65. The median difference (CT-pool–CT samples) was 2.4 (ranging from–3.0 to 8.9). The correlation of CT of pools and positive samples was positive. The correlation coefficient r = 0.84, P < 0.000, 95% CI range 0.7423 to 0.9243). The total economic saving when using pools compared to the individual testing was 72%. The minor difference between CT values of pools and samples can be explained by the dilution effect in the pool. However, the positive correlation between the values as well as the amount of cost saving demonstrate that pooling on nasopharyngeal samples for COVID-19 PCR testing can be a good method for efficient screening with significant resource saving. One of the most important advantages of the proposed method is

关键词： COVID-19 Screening Grouped Testing

Generic Modeling and Control Framework for Power systems Dominated by Power Converters Connected Through a Passive Transmission and Distribution Grid

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CSEE Journal of Power and Energy systems 2024年第1期10卷 292-301页

作者： Qing-Chang Zhong Marcio Stefanello Department of Electrical and Computer Engineering Illinois Institute of TechnologyChicagoIL 60616USA Syndem llc USA.M.Stefanello is with the Fundacao Universidade Federal do Pampa at AlegreteRS97546-550Brazil

In this paper,a compact mathematical model having an elegant structure,together with a generic control framework,are proposed for generic power systems dominated by power converters that are interconnected through a passive transmission and distribution(T&D)grid,by adopting the port-Hamiltonian(pH)systems theory and the fundamental circuit *** models of generic T&D lines are developed and then the model of a generic T&D grid is *** the proposed control framework,the controlled converters are proven to be passive and Input-to-State Stable(ISS).The compact mathematical model is scalable and can be applied to power systems with multiple power electronic converters with generic passive controllers,passive local loads,and different types of passive T&D lines connected in a meshed configuration without self-loops,so it is very ***,the resulting power system is proven to be ISS as *** analysis is carried out without assumptions on constant frequency/voltage,constant loads,and/or lossless networks,except the need of passivity for all parts involved,and without using the Clarke/Park transformations or the graph *** simplify the presentation,three-phase balanced systems are adopted but the results can be easily adapted for single-phase or unbalanced three-phase systems.

关键词： Input-to-State Stable(ISS) passivity,portHamiltonian(pH)systems Power electronic converters dominated power systems Synchronized and Democratized(SYNDEM)grid architecture

A Review: Manufacturing, and Properties of the D-Fructose Epimer D-Allulose (D-Psicose)

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Advances in Bioscience and Biotechnology 2024年第9期15卷 522-542页

作者： Osama O. Ibrahim Bioinnovation llc Gurnee IL USA

D-allulose, also known by the name D-psicose or just allulose, is a rare keto-sugar epimer of D-fructose in the third carbon (C3), and naturally occurs in small quantity in fruits such as grapes and figs. It is low calorie sweetener produced enzymatically from D-fructose by enzymes D-ketose 3-epimerase (DKEase) family. D-allulose has a similar taste, texture and functionality as sweetener comparing to high calorie sweetener sugar table sucrose. D-allulose is poorly metabolized in the body with minimal impact on blood sugar levels making it a natural low-calorie sweetener. This property makes D-allulose an attractive sweetener for diabetes and for body weight management. Laboratory studies on D-allulose intake demonstrated its safety with no significant adverse effects. United States Food and Drug Administration (FDA) has granted D-allulose the status of Generally Recognized as Safe (GRAS). Plus, it is considered safe for human consumption by regulatory organizations in other countries except in European Union due to their request for further laboratory testing. Maximum acceptable daily intake of D-allulose is 0.9 grams per kilogram body weight. Excessive intake for more than the recommended daily intake could lead to some side effects such as gastrointestinal discomfort or laxative effects. In general, D-allulose is considered one of the preferred natural low calories sweeteners for those seeking an alternative to table sugar sucrose.

关键词： D-Allulose D-Ketose 3-Epimerase (DKEase) D-Tagatose 3-Epimerase (DTEase) D-Allulose 3-Epimerase (DAEase) D-Psicose 3-Epimerase (DPEase)

Global Solutions to Nonconvex Problems by Evolution of Hamilton-Jacobi PDEs

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Communications on Applied Mathematics and Computation 2024年第2期6卷 790-810页

作者： Howard Heaton Samy Wu Fung Stanley Osher Typal Research Typal LLCLos AngelesUSA Department of Applied Mathematics and Statistics Colorado School of MinesGoldenUSA Department Mathematics UCLALos AngelesUSA

Computing tasks may often be posed as optimization *** objective functions for real-world scenarios are often nonconvex and/or ***-of-the-art methods for solving these problems typically only guarantee convergence to local *** work presents Hamilton-Jacobi-based Moreau adaptive descent(HJ-MAD),a zero-order algorithm with guaranteed convergence to global minima,assuming continuity of the objective *** core idea is to compute gradients of the Moreau envelope of the objective(which is"piece-wise convex")with adaptive smoothing *** of the Moreau envelope(i.e.,proximal operators)are approximated via the Hopf-Lax formula for the viscous Hamilton-Jacobi *** numerical examples illustrate global convergence.

关键词： Global optimization Moreau envelope Hamilton-Jacobi Hopf-Lax-Cole-Hopf Proximals Zero-order optimization

A rat model of multicompartmental traumatic injury and hemorrhagic shock induces bone marrow dysfunction and profound anemia

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Animal Models and Experimental Medicine 2024年第3期7卷 367-376页

作者： Lauren S.Kelly Jennifer A.Munley Erick E.Pons Kolenkode B.Kannan Elizabeth M.Whitley Letitia E.Bible Philip A.Efron Alicia M.Mohr Department of Surgery and Sepsis and Critical Illness Research Center University of Florida College of MedicineGainesvilleFloridaUSA Pathogenesis LLCGainesvilleFloridaUSA

Background:Severe trauma is associated with systemic inflammation and organ *** rodent trauma models are the mainstay of postinjury research but have been criticized for not fully replicating severe human *** aim of this study was to create a rat model of multicompartmental injury which recreates profound traumatic ***:Male Sprague-Dawley rats were subjected to unilateral lung contusion and hemorrhagic shock(LCHS),multicompartmental polytrauma(PT)(unilateral lung contusion,hemorrhagic shock,cecectomy,bifemoral pseudofracture),or na?ve ***,plasma toll-l ike receptor 4(TLR4),hemoglobin,spleen to body weight ratio,bone marrow(BM)erythroid progenitor(CFU-GEMM,BFU-E,and CFU-E)growth,plasma granulocyte colony-stimulating factor(G-CSF)and right lung histologic injury were assessed on day 7,with significance defined as p values<0.05(*).Results:Polytrauma resulted in markedly more profound inhibition of weight gain compared to LCHS(p=0.0002)along with elevated plasma TLR4(p<0.0001),lower hemoglobin(p<0.0001),and enlarged spleen to body weight ratios(p=0.004).Both LCHS and PT demonstrated suppression of CFU-E and BFU-E growth compared to naive(p<0.03,p<0.01).Plasma G-CSF was elevated in PT compared to both na?ve and LCHS(p<0.0001,p=0.02).LCHS and PT demonstrated significant histologic right lung injury with poor alveolar wall integrity and interstitial ***:Multicompartmental injury as described here establishes a reproducible model of multicompartmental injury with worsened anemia,splenic tissue enlargement,weight loss,and increased inflammatory activity compared to a less severe *** may serve as a more effective model to recreate profound traumatic injury to replicate the human inflammatory response postinjury.

关键词： anemia i nflammation polytrauma pseudofracture shock

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