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Science China(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO jiale WU Zhijie lIU We HE C.l.Philip CHEN School of Mechanical and Electrical Engineering Guangzhou University School of Intelligence Science and Technology and Key laboratory of Intelligent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School of Computer Science and Engineering South China University of Technology Pazhou lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed ***, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. Second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. Subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

Continuity of care by a primary midwife(caseload midwifery):a cost analysis using results from the COSMOS randomised controlled trial

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Gynecology and Obstetrics Clinical Medicine 2024年第2期4卷 94-101页

作者： Emily j Callander Hannah jackson Helen l Mclachlan Mary-Ann Davey Della A Forster University of Technology Sydney SydneyNew South WalesAustralia The Royal Women's Hospital MelbourneVictoriaAustralia Faculty of Health University of Technology SydneyBroadwayNew South WalesAustralia judith lumley Centre La Trobe UniversityMelbourneVictoriaAustralia School of Nursing and Midwifery a Trobe UniversityMelbourneVictoriaAustralia Department of Obstetrics and Gynaecology Monash UniversityClaytonVictoriaAustralia

Introduction Caseload midwifery(continuity of midwifery carer)offers benefits including lower caesarean section rates,lower risks of preterm birth and stilbirth,and improved maternal satisfaction of *** these advantages,concerns about additional costs hinder widespread *** study examinesthecost of caseload midwifery compared with standard maternity care from the perspective of both public hospitals and public *** A cost analysis was conducted using data from a randomised controlled trial of 2314 low-risk pregnant women in Melbourne,*** randomised to caseload care received antenatal,intrapartum and postpartum care from a primary midwife,with some care provided by a‘back-up'*** in standard care received midwifery-led care with varying levels of continuity,junior obstetric care or community-based medical *** cost analysis compared differences in mean costs of health resources to public hospitals and to public ***,a budget impact analysis estimated total costs to the health system between 2023 and *** For public hospitals,there was no significant difference in overall costs between women receiving caseload midwifery(n=1146)versus standard care(n=1151)($SA12363(SD:$A4967)vs$A12323(SD:$A7404);p=0.85).Conversely,public funders incurred lower expenditures for women receiving caseload midwifery($A20330(SD:$A8312))versus standard care($A21637(SD:$A11818);plysis estimated savings of sA625million to the health system over the next 5 years with expanded access to caseloadmidwifery *** Caseloadmidwifery in low-risk women is cost-neutral to public hospitals and cost-saving to public *** abstract Continuity of midwifery for low-risk women reduces costs to public funders,with no additional costs to hospitals.

关键词： random continuity Continuity

Solid-state NMR studies of proteins in condensed phases

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Magnetic Resonance letters 2024年第3期4卷 1-10页

作者： jiani Xiang Xialian Wu Angelo l.Chu junxia lu Key laboratory of Industrial Fermentation(Ministry of Education) School of Life and Health SciencesHubei University of TechnologyWuhan430068China Interdisciplinary Institute of NMR and Molecular Sciences School of Chemistry and Chemical EngineeringThe State Key Laboratory of Refractories and MetallurgyWuhan University of Science and TechnologyWuhan430081China Thomas jefferson High School for Science and Technology 6560 Braddock RdAlexandriaVA22312USA

Some proteins perform their biological functions by changing their material states through liquid-liquid phase *** phase separation,the protein condenses into a concentrated liquid phase and sometimes into a gel phase,changing its dynamic properties and intermolecular interactions,thereby regulating cellular *** the biological significance of this phenomenon has been widely recognized by researchers,there is still a lack of a comprehensive understanding of the structural and dynamic properties of the protein in the condensed *** this phase,molecules usually contain domains with varied dynamic properties and undergo intermediate *** angle spinning(MAS)solid-state NMR(SSNMR)experiments are very powerful in studying rigid protein polymers such as *** incorporation of solution-like experiments into SSNMR and the development of j-coupling based MAS SSNMR techniques extend its ability to study partially mobile segments of proteins in a condensed liquid or gel phase which are not visible by solution NMR or dipolar-coupling based ***,it has been applied in studying protein condensation and has provided very important information that is hard to obtain by other techniques.

关键词： Magic angle spinning(MAS)solid-state NMR(SSNMR) Protein condenses j-coupling based MAS SSNMR liquid-liquid phase separation

Evolution of microstructure and properties of a novel Ni-based superalloy during stress relief annealing

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International journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1876-1889页

作者： lei jia Heng Cui Shufeng Yang Shaomin lü Xingfei Xie jinglong Qu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China State Key laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing GAONA Materials&Technology Co. Ltd.Beijing 100081China High-Temperature Materials Institute Central Iron and Steel Research InstituteBeijing 100081China

We discussed the decrease in residual stress,precipitation evolution,and mechanical properties of GH4151 alloy in different annealing temperatures,which were studied by the scanning electron microscope(SEM),high-resolution transmission electron microscopy(HRTEM),and electron backscatter diffraction(EBSD).The findings reveal that annealing processing has a significant impact on diminishing residual *** the annealing temperature rose from 950 to 1150℃,the majority of the residual stresses were relieved from 60.1 MPa down to 10.9 ***,the stress relaxation mechanism transitioned from being mainly controlled by dislocation slip to a combination of dislocation slip and grain boundary ***,the annealing treatment promotes the decomposition of the laves,accompanied by the precipitation ofμ-(Mo_(6)Co_(7))starting at 950℃ and reaching a maximum value at 1050℃.The tensile strength and plasticity of the annealing alloy at 1150℃ reached the maximum(1394 MPa,56.1%)which was 131%,200%fold than those of the as-cast alloy(1060 MPa,26.6%),but the oxidation process in the alloy was accelerated at 1150℃.The enhancement in durability and flexibility is primarily due to the dissolution of the brittle phase,along with the shape and dispersal of theγ′phase.

关键词： GH4151 alloy annealing treatment residual stress precipitation evolution strength mechanical properties

Deadlock-free dynamic resource assignment in multi-robot systems with multiple missions:application in wireless sensor networks

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控制理论与应用（英文版） 2010年第1期8卷 12-19页

作者： P.M.BAllAl A.C.TRIVEDI V.GIORDANO j.MIRElES jr. F.l.lEWIS Automation & Robotics Research Institute University of Texas at Arlington

In unstructured environments, dynamic resource assignment is required for effective cooperation of robot teams. In some scenarios, robots are in charge of executing multiple missions simultaneously. This creates risks of deadlock due to the presence of shared resources among various missions. The main contribution of this paper is the development of a novel approach that combines the one-step look-ahead deadlock avoidance policy with dynamic resource assignment. The dynamicresource assignment is achieved using greedy resource assignment for multi-mission robot teams in the framework of a matrix-based discrete event controller. Simulation results are presented in MATlAB to discuss in detail the proposed control strategy. The paper also discusses the toolkit developed in labVIEW which is used to implement this control framework using a suitable example.

关键词： Discrete event systems Wireless sensor networks Deadlock avoidance Petri nets

Surface engineering with ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang Chenyi Fang j Paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 l·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

Time-lapse 3-D Seismic Wave Simulation via the Generalized Multiscale Finite Element Method

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Communications in Computational Physics 2020年第6期28卷 401-423页

作者： Yongchae Cho Richard l.Gibson,jr. Hyunmin Kim Mikhail Artemyev Yalchin Efendiev Shell International Exploration&Production Inc. 150 N Dairy Ashford RoadHoustonTX 77079USA Department of Geology&Geophysics Texas A&M UniversityCollege StationTexas 77843-3115USA Shell Exploration&Production Company 701 Poydras StreetNew OrleansLA 70139USA Arista Networks DublinIreland Department of Mathematics Texas A&M UniversityCollege StationTexas 77843-3368USA Multiscale Model Reduction laboratory North-Eastern Federal UniversityYakutskRepublic of Sakha 677980Russia

Numerical solution of time-lapse seismic monitoring problems can be challenging due to the presence of finely layered *** wave modeling using fine layered meshes also adds more computational *** approaches such as finite difference and finite element methods may be prohibitively expensive if the whole domain is discretized with the cells corresponding to the grid in the reservoir subdomain.A common approach in this case is to use homogenization techniques to upscale properties of subsurface media and assign the background properties to coarser grid;however,inappropriate application of upscaling might result in a distortion of the model,which hinders accurate monitoring of the fluid change in *** this work,we instead investigate capabilities of a multiscale method that can deal with fine scale heterogeneities of the reservoir layer and more coarsely meshed rock properties in the surrounding domains in the same *** address the 3-D wave problems,we also demonstrate how the multiscale wave modeling technique can detect the changes caused by fluid movement while the hydrocarbon production activity proceeds.

关键词： Fluid simulation time lapse Generalized multiscale finite element elastic wave

Quantitative Applications of Weather Satellite Data for Nowcasting:Progress and Challenges

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journal of Meteorological Research 2024年第3期38卷 399-413页

作者： jun lI jing ZHENG Bo lI Min MIN Yanan lIU Chian-Yi lIU Zhenglong lI WPaul MENZEl Timothy j.SCHMIT john l.CINTINEO Scott lINDSTROM Scott BACHMEIER Yunheng XUE Yayu MA Di DI Han lIN Innovation Centre for Fengyun Meteorological Satellite(FYSIC) National Satellite Meteorological CentreChina Meteorological AdministrationBeijing100081China School of Atmospheric Sciences and Guangdong Province Key laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University and Southern Laboratory of Ocean Science and EngineeringZhuhai519082China Key laboratory of Geographic Information Science(Ministry of Education) East China Normal UniversityShanghai200241China Research Center for Environmental Changes Academia SinicaTaipei11529China Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-MadisonMadisonWI53706USA Sensors and Calibration Branch STAR/NESDISMadisonWI53706USA Wuxi University Wuxi214105China School of Computer Science Chengdu University of Information TechnologyChengdu610225China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing210044China Key laboratory of Spatial Data Mining and Information Sharing of Ministry of Education National and Local Joint Engineering Research Center of Satellite Geospatial Information TechnologyFuzhou UniversityFuzhou350108China

Monitoring and predicting highly localized weather events over a very short-term period,typically ranging from minutes to a few hours,are very important for decision makers and public *** these events usually relies on radar observations through monitoring and *** advanced high-resolution imaging and sounding observations from weather satellites,nowcasting can be enhanced by combining radar,satellite,and other data,while quantitative applications of those data for nowcasting are advanced through using machine learning *** applications include monitoring the location,impact area,intensity,water vapor,atmospheric instability,precipitation,physical properties,and optical properties of the severe storm at different stages(pre-convection,initiation,development,and decaying),identification of storm types(wind,snow,hail,etc.),and predicting the occurrence and evolution of the *** observations can provide information on the environmental characteristics in the preconvection stage and are very useful for situational awareness and storm *** paper provides an overview of recent progress on quantitative applications of satellite data in nowcasting and its challenges,and future perspectives are also addressed and discussed.

关键词： weather satellite quantitative applications nowcasting pre-convection

Improved Analytical Methods for Determination of Residues of Nitrapyrin and 6-Chloropicolinic Acid in Different Crop Matrices by liquid Chromatography-Tandem Mass Spectrometry

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journal of Agricultural Chemistry and Environment 2024年第3期13卷 263-281页

作者： Fabiola G. Zuno-Floriano Riza l. Reyes-Punongbayan Matt j. Hengel Department of Environmental Toxicology University of California Davis California USA

Novel analytical methods were developed for the determination of nitrapyrin and 6-chloropicolinic acid (6-CPA) residues in agricultural products. Nitrapyrin was extracted with hexane: toluene (1:1, v/v) and 6-CPA with 0.1 N sodium hydroxide (NaOH). For nitrapyrin, samples were cleaned with silica solid phase extraction (SPE) and for 6-CPA with C18 or carbon SPE. Analysis was performed by liquid chromatography-tandem mass spectroscopy (lC-MS/MS) with external calibration (0.010 to 0.0010 µg∙ml−1 for nitrapyrin and 0.0050 to 0.00025 µg∙ml−1 for 6-CPA). Recoveries for nitrapyrin and 6-CPA were 68% - 102% and 66% - 90%, respectively. Nitrapyrin was detected in celery and onion (−1) and 6-CPA in onion, mustard greens and lettuce (−1). lower level method validation (llMV) for nitrapyrin and 6-CPA was 0.020 µg∙g−1 and 0.050 µg∙g−1, respectively. The methods presented in this study are robust and were utilized for the registration of nitrapyrin on agricultural commodities in the United States.

关键词： Herbicide Agricultural Products External Calibration lC-MS/MS Registration

急性呼吸困难患者中白介素家族成员ST2的测定:PRIDE(急诊科呼吸困难患者脑利钠肽前体)研究的结果

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世界核心医学期刊文摘（心脏病学分册） 2007年第12期3卷 54-55页

作者： januzzi jr. j.l. PeacockW.F. Maisel A.S. 黄欣 Department of Medicine Laboratory Medicine Massachusetts General Hospital Boston MA United States

目的:本研究旨在确定在呼吸困难患者中测定白介素-1受体家族成员ST2的价值。背景:据报道,心力衰竭(HF)患者中ST2浓度升高。方法:对593例就诊于市区急诊科的伴或不伴急性不稳定性HF的呼吸困难患者测定其ST2浓度。识别1年死亡的独立预测... 详细信息

目的:本研究旨在确定在呼吸困难患者中测定白介素-1受体家族成员ST2的价值。背景:据报道,心力衰竭(HF)患者中ST2浓度升高。方法:对593例就诊于市区急诊科的伴或不伴急性不稳定性HF的呼吸困难患者测定其ST2浓度。识别1年死亡的独立预测因素。

关键词：呼吸困难 ST2 PRIDE 急诊科患者白介素