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Reinforcement learning and A^(*)search for the unit commitment problem patrick de Mars^(∗),Aidan O’Sullivan

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Energy and AI 2022年第3期9卷 172-181页

作者： patrick de Mars Aidan O’Sullivan UCL Energy Institute United Kingdom

Previous research has combined model-free reinforcement learning with model-based tree search methodsto solve the unit commitment problem with stochastic demand and renewables generation. This approachwas limited to shallow search depths and suffered from significant variability in run time across probleminstances with varying complexity. To mitigate these issues, we extend this methodology to more advancedsearch algorithms based on A^(*) search. First, we develop a problem-specific heuristic based on priority list unitcommitment methods and apply this in Guided A^(*) search, reducing run time by up to 94% with negligibleimpact on operating costs. In addition, we address the run time variability issue by employing a novel anytimealgorithm, Guided IDA^(*), replacing the fixed search depth parameter with a time budget constraint. We showthat Guided IDA^(*) mitigates the run time variability of previous guided tree search algorithms and enablesfurther operating cost reductions of up to 1%.

关键词： Unit commitment Reinforcement learning Tree search Power systems

Genome-wide association and genomic prediction identifies soybean cyst nematode resistance in common bean including a syntenic region to soybean Rhg1 locus

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Horticulture Research 2019年第1期6卷 1734-1745页

作者： Liwei Wen Hao-Xun Chang patrick j.Brown Leslie L.Domier Glen L.Hartman Department of Crop Sciences University of IllinoisUrbanaIL 61801USA United States Department of Agriculture—Agricultural Research Service UrbanaILUSA Monsanto St.LouisMO 63167USA Department of Plant Soil and Microbial SciencesMichigan State UniversityEast LansingMI 48824USA Department of Plant Sciences University of CaliforniaDavisCA 95616USA

A genome-wide association study(GWAS)was applied to detect single nucleotide polymorphisms(SNPs)significantly associated with resistance to Heterodera glycines(HG)also known as the soybean cyst nematode(SCN)in the core collection of common bean,Phaseolus *** were 84,416 SNPs identified in 363 common bean *** identified SNPs on chromosome(Chr)1 that were significantly associated with resistance to HG type *** SNPs were in linkage disequilibrium with a gene cluster orthologous to the three genes at the Rhg1 locus in soybean.A novel signal on Chr 7 was detected and associated with resistance to HG type *** predictions(GPs)for resistance to these two SCN HG types in common bean achieved prediction accuracy of 0.52 and 0.41,*** study generated a high-quality SNP panel for 363 common bean accessions and demonstrated that both GWAS and GP were effective strategies to understand the genetic architecture of SCN resistance in common bean.

关键词： soybean resistance prediction

Hemispheric Specialization of the Primate Inferior Parietal Lobule

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Neuroscience Bulletin 2022年第3期38卷 334-336页

作者： Sam Vickery Simon B Eickhoff patrick Friedrich Institute of Neuroscience and Medicine Brain&Behaviour(INM-7)Research Centre Jülich52428JülichGermany Institute of Systems Neuroscience Medical FacultyHeinrich-Heine University Düsseldorf40225DüsseldorfGermany

Hemispheric asymmetries can be seen as one of the evolutionary adaptations that allowed the human brain to muster more complex cognitive processes than other *** this vein,the study published by Cheng et al.[1]presents a pivotal investigation of both the regional and connectional asymmetries within the inferior parietal lobule(IPL)in human,chimpanzee,and *** investigating 4 sub-divisions of the IPL across the three species,Cheng and colleagues showed that the macroanatomical and connectional architecture of the IPL became more asymmetric throughout the primate *** macaques show little to no structural asymmetries,chimpanzees display a more asymmetric architecture but with both leftward and rightward asymmetries in various *** contrast,the human IPL displayed the highest number of asymmetries among the three species with a clear tendency towards more *** evolutionary trend towards a more lateralized organization of the IPL may have accompanied an improved command of tool-use,stronger forelimb asymmetries,and the increasing complexity of communicative behavior.

关键词： asymmetric erior allowed

Gas flow in rotary kilns

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Particuology 2010年第6期8卷 613-616页

作者： patrick R.Davies Michael j.S.Norton D.Ian Wilson j.hn F.Davidson David M.Scott Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridgeCB2 3RAUK

This paper describes an experimental investigation on the flow characteristics within a rotating cylinder containing a rolling bed of sand. The axis of the cylinder was horizontal and there was no axial bulk flow of particles. The velocity field of the gas flowing through the cylinder was measured by hot-wire anemometry. The measurements indicate that the velocity field is asymmetric with respect to a diameter perpendicular to the granular bed. CFD calculations confirm this finding. The gas velocity profiles are crucial in determining heat transfer from gas to solid.

关键词： Rotating cylinderVelocity profile

3D modeling of abnormal pore pressure in shallow offshore Niger delta: An application of seismic inversion

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Petroleum Research 2021年第2期6卷 158-171页

作者： Chukwuemeka patrick Abbey Osita Chukwudi Meludu Adetola Sunday Oniku a a Department of Physics Modibbo Adama University of Technology YolaNigeria Department of Petroleum Chemistry&Physics American University of NigeriaNigeria

Pore pressure is the pressure associated with fluids in the pore spaces of sedimentary rocks. Thispressure varies from hydrostatic to severe overpressure. It is classified as abnormal pressure when itdeviates from hydrostatic pressure. Incorrect prediction or the absence of pore pressure evaluation canlead to severe damage of the drilling platform, loss of personnel, waste of resources and environmentalpollution. This study was carried out in an offshore field in Niger Delta with an obj.ctive of predicting theabnormal pressure regime from the seismic volume using seismic inversion technique. First, weemployed the Eaton’s and Bower’s model of predicting pore pressure from Well log. The predicted porepressure from the well was used to calibrate the P-impedance that was used in the inversion process. Apressure-based model for the seismic inversion process was developed. This was constrained by therelationship between the P-impedance and pore pressure in the study area. The predicted pore pressurefrom the Well logs aligned with the measured pore pressure in the formation. At about 3600 m to end ofthe Well, depicts a pressure regime that is a deviation from the hydrostatic pressure trend. The abnormalpressure regime is marked by the region where a change is observed in the normal compaction trendline. The cross plot of acoustic impedance against pore pressure reveals a linear relationship;with adirect relationship indicating a normal pressure interval and the indirect relationship at the abnormalpressure regime. The inverted 3D pressure result from the seismic volume validates the normalcompaction trend line and also the pressure values estimated from the Well logs. The abnormal pressureregime in the study area is predicted to be found towards the end of Agbada Formation and through theAkata Formation due to the un-compacted shales.

关键词： Acoustic impedance Pressure Seismic inversion Formation Overpressure

Geotechnical behavior of uranium mill tailings from Saskatchewan,Canada

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International j.urnal of Mining Science and Technology 2016年第3期26卷 369-375页

作者： Bhuiyan Imteaz Azam Shahid Khaled Shifullah Landine patrick Environmental Systems Engineering University of Regina Thurber Engineering Limited Cameco Corporation

This paper investigates the geotechnical behavior of uranium mill tailings from Saskatchewan, *** 4% tailings were well-graded with 29% fines whereas the 5% and 6% tailings were gap-graded with 49% fines. All samples exhibited a negligible strength(0.4 k Pa) up to 60% solids, followed by a rapid increase. The 4% tailings exhibited a lower rate and amount of settlement than 5% and 6% tailings. The kidecreased from 10^(-2)to 10^(-4)m/s with a decrease in eifrom 16 to 4 and a decrease in ef from 8 to 4 such that 4% tailings showed one order of magnitude lower values than the 5% and 6%tailings. The settling potential decreased ten times(50%–5%) for 4% tailings and four times(60%–15%)for 5% and 6% tailings. The effective stress increased from 80 to 260 Pa in the settling tests. The 4%tailings were less prone to segregation when compared with 5% and 6% tailings. The average solids content after settling was 35% for 4% tailings, 40% for 5% tailings and 39% for 6% tailings with a solids content deviation of ±3%, ±8%, ±6%, respectively. All materials were essentially non-segregating at 40%initial solids.

关键词： Uranium mill tailings Rheology Settling Segregation

Generic functional modelling of multi-pulse auto-transformer rectifier units for more-electric aircraft applications

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Chinese j.urnal of Aeronautics 2018年第5期31卷 883-891页

作者： Tao YANG Serhiy BOZHKO patrick WHEELER Shaoping WANG Shuai WU Department of Electrical and Electronic Engineering University of Nottingham School of Automation Science and Electrical Engineering Beihang University

The Auto-Transformer Rectifier Unit（ATRU） is one preferred solution for high-power AC/DC power conversion in aircraft. This is mainly due to its simple structure, high reliability and reduced k VA ratings. Indeed, the ATRU has become a preferred AC/DC solution to supply power to the electric environment control system on-board future aircraft. In this paper, a general modelling method for ATRUs is introduced. The developed model is based on the fact that the DC voltage and current are strongly related to the voltage and current vectors at the AC terminals of ATRUs. In this paper, we carry on our research in modelling symmetric 18-pulse ATRUs and develop a generic modelling technique. The developed generic model can study not only symmetric but also asymmetric ATRUs. An 18-pulse asymmetric ATRU is used to demonstrate the accuracy and efficiency of the developed model by comparing with corresponding detailed switching SABER models provided by our industrial partner. The functional models also allow accelerated and accurate simulations and thus enable whole-scale more-electric aircraft electrical power system studies in the future.

关键词： Asymmetric transformer Functional modelling More-Electric Aircraft Multi-pulse rectifier Transformer rectifier unit

Monolithic membrane reactors based on supported ionic liquid phase(SILP)materials–hydroformylation and water-gas shift case studies

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Green Chemical Engineering 2021年第4期2卷 339-341页

作者： Markus Schorner patrick Wolf Marco Haumann Friedrich-Alexander-Universitaat Erlangen-Nürnberg(FAU) Lehrstuhl für Chemische Reaktionstechnik(CRT)Egerlandstr.391058ErlangenGermany Forschungszentrum j.lich GmbH Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy(IEK 11)Cauerstr.191058ErlangenGermany

Homogeneous catalysts,usually being active in liquid environment,offer several benefits for highly selective ***,the often tedious product separation and catalyst recycling,requiring energy and chemical input,renders such processes energy ***,process intensification can help to achieve a significant reduction in energy consumption and CO_(2) *** this context,monolithic membrane reactors combining homogeneous catalysis with in-situ product removal are highly *** order to maintain the homogeneous catalyst inside the monolithic structure,the so-called supported ionic liquid phase(SILP)technique is *** such SILP systems,the active catalyst is dissolved in an ionic liquid,which is dispersed as thin film over the large internal surface of a porous support[1].

关键词： ionic catalyst liquid

End-tidal capnometry during emergency department procedural sedation and analgesia： a randomized, controlled study

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World j.urnal of Emergency Medicine 2016年第1期7卷 13-18页

作者： Samuel G. Campbell Kirk D. Magee Peter j. Zed patrick Froese Glenn Etsell Alan LaPierre Donna Warren Robert R. MacKinley Michael B. Butler George Kovacs David A. Petrie Department of Emergency Medicine and Anesthesia Dalhousie University Halifax Nova Scotia Canada Faculty of Pharmaceutical Sciences and Department of Emergency Medicine University of British Columbia Vancouver BC Canada Charles V. Keating Emergency and Trauma Centre Halifax Nova Scotia Canada Department of Emergency Medicine Anesthesia and Anatomy Dalhousie University Halifax Nova Scotia Canada

BACKGROUND:This prospective,randomized trial was undertaken to evaluate the utility of adding end-tidal capnometry(ETC)to pulse oximetry(PO)in patients undergoing procedural sedation and analgesia(PSA)in the emergency department(ED).METHODS:The patients were randomized to monitoring with or without ETC in addition to the current standard of *** endpoints included respiratory adverse events,with secondary endpoints of level of sedation,hypotension,other PSA-related adverse events and patient ***:Of 986 patients,501 were randomized to usual care and 485 to additional ETC *** this series,48%of the patients were female,with a mean age of 46 *** manipulations(71%),cardioversion(12%)and abscess incision and drainage(12%)were the most common procedures,and propofol and fentanyl were the sedative/analgesic combination used for most *** was no difference in patients experiencing de-saturation(Sa O2<90%)between the two groups;however,patients in the ETC group were more likely to require airway repositioning(12.9%vs.9.3%,P=0.003).Hypotension(SBP<100 mm Hg or<85 mm Hg if baseline<100 mm Hg)was observed in 16(3.3%)patients in the ETC group and 7(1.4%)in the control group(P=0.048).CONCLUSIONS:The addition of ETC does not appear to change any clinically significant *** found an increased incidence of the use of airway repositioning maneuvers and hypotension in cases where ETC was *** do not believe that ETC should be recommended as a standard of care for the monitoring of patients undergoing PSA.

关键词： Procedural sedation and analgesia Capnography Adverse events Emergency medicine