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Novel high-safety aeroengine performance predictive control method based on adaptive tracking weight

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Chinese Journal of Aeronautics 2024年第7期37卷 352-374页

作者： Qian CHEN Hanlin sheng jie ZHANG Jiacheng LI College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation *** latest research demonstrates that Subspace-based Improved Model Predictive Control(SIMPC)can overcome the difficulty in solving the predictive model in MPC/NMPC ***,applying constant design parameters cannot maintain consistent control effects in all ***,the designed system relies too much on sensor-measured data,and thus it is difficult to thoroughly validate the safety of the system because of its high *** means that any potential hardware/software faults will endanger the ***,this paper first presents a novel nonlinear mapping relationship to adaptively tune the tracking weight online with the change of Power Lever Angle(PLA)and real-time relative tracking ***,without introducing additional design parameters,an Adaptive Tracking Weight-based SIMPC(ATW-SIMPC)controller is designed to improve the control performance in all operating states ***,a Primary/Backup Hybrid Control(PBHC)strategy with the ATW-SIMPC controller as the primary system and the traditional speed(Nf)controller as the backup system is proposed to ensure *** designed affiliated switching controller and the real-time monitor therein can be used to realize reasonable and smooth switching between primary/backup systems,so as to avoid bump *** PBHC system switches to the Nf controller when the ATW-SIMPC controller is wrong because of potential hardware/software faults;otherwise,the ATW-SIMPC controller keeps acting on the *** main results prove that the ATW-SIMPC controller with the optimal nonlinear mapping relationship,compared with the existing SIMPC controller,uplifts the dynamic control performance by 32%and reduces overshoots to an allowable limit,resulting in a better control effect in full *** comparison results consistently i

关键词： Aeroengine Model predictive control Hybrid system Adaptive weight Safety

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Electrochemical Mono-Deuterodefluorination of Trifluoromethyl Aromatic Compounds with Deuterium Oxide

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CCS Chemistry 2024年第1期6卷 230-240页

作者： jie sheng Xu Cheng Institute of Chemistry and Biomedical Sciences Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023 State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 30071

The deuterodifluoromethyl group CF_(2)D combines the structural features of CF_(3) and CD_(3) groups,finding wide applications in diverse pharmaceutical *** this work,the electrochemical monodeuterodefluorination of Ar-CF_(3) to Ar-CF_(2)D is achieved with an unreported deuterium atom transfer-coupled electron transfer pathway using D_(2)O as the only D source for the first time.A series of Ar-CF_(3) substances,including commercial pharmaceuticals,were converted to corresponding CF_(2)D products in up to 91% yield and 97% D-incorporation.A variety of functional groups,including pyridine,pyrrole,furan,thiophene,borate,thio ether,amine,amide,sulfonamide,and halide,are well tolerated in this protocol.t-BuOLi was an essential reagent to achieve chemoselective mono-defluorination.

关键词： electrochemistry C-F activation fluorinecontaining drugs deuterated drugs deuterium oxide

Single-structure 3-axis Lorentz force magnetometer based on an AlN-on-Si MEMS resonator

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Microsystems & Nanoengineering 2024年第3期10卷 75-86页

作者： Cheng Tu Xu-heng Ou-Yang Ying-jie Wu Xiao-sheng Zhang School of Integrated Circuit Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

This work presents a single-structure 3-axis Lorentz force magnetometer(LFM)based on an AlN-on-Si MEMS *** operation of the proposed LFM relies on the flexible manipulation of applied excitation currents in different directions and frequencies,enabling the effective actuation of two mechanical vibration modes in a single device for magnetic field measurements in three ***,the excited out-of-plane drum-like mode at 277 kHz is used for measuring the x-and y-axis magnetic fields,while the in-plane square-extensional mode at 5.4 MHz is used for measuring the z-axis magnetic *** different configurations of applied excitation currents ensure good crossinterference immunity among the three *** to conventional capacitive LFMs,the proposed piezoelectric LFM utilizes strong electromechanical coupling from the AlN layer,which allows it to operate at ambient pressure with a high *** understand and analyze the measured results,a novel equivalent circuit model for the proposed LFM is also reported in this work,which serves to separate the effect of Lorentz force from the unwanted capacitive *** demonstrated 3-axis LFM exhibits measured magnetic responsivities of 1.74 ppm/mT,1.83 ppm/mT and 6.75 ppm/mT in the x-,y-and z-axes,respectively,which are comparable to their capacitive counterparts.

关键词： resonator Lorentz structure

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World Journal of Emergency Medicine 2024年第4期15卷 256-262页

作者： jie Er Janice soo Yuan Helen Zhang Gek Hsiang Lim Fatimah Lateef Department of Emergency Medicine Singapore General HospitalSingapore 168753Singapore Health Services Research Unit Singapore General HospitalSingapore168753Singapore

BACKGROUND:This study aimed to review bicycle-related injuries during the COVID-19 pandemic to assist with reinforcement or implementation of new policies for injury ***:This is a retrospective descriptive analysis of injuries sustained during cycling for patients 18 years old and above who presented to Singapore General Hospital from January to June *** records were reviewed and *** analyses were used to summarize patient characteristics,and differences in characteristics subgrouped by triage acuity and discharge status were ***:The study included 272 patients with a mean age of 43 years and a male predominance(71.7%).Most presented without referrals(88.2%)and were not conveyed by ambulances(70.6%).Based on acuity category,there were 24(8.8%)Priority 1(P1)patients with 7 trauma activations,174(64.0%)and 74(27.2%)P2 and P3 patients *** most common injuries were fractures(34.2%),followed by superficial abrasion/contusion(29.4%)and laceration/wound(19.1%).Thirteen(4.8%)patients experienced head injury and 85 patients(31.3%)were documented to be wearing a *** majority occurred on the roads as traffic accidents(32.7%).Forty-two patients(15.4%)were admitted with a mean length of stay of 4.1 d and 17(6.3%)undergone surgical *** of 214(78.7%)discharged patients,no re-attendances or mortality were *** the subgroup analysis,higher acuity patients were generally older,with higher proportions of head injuries leading to ***:Our study highlights significant morbidities in bicycle-related *** is also a high proportion of fractures in the young healthy male *** prevention is paramount and we propose emphasizing helmet use and road user safety.

关键词： Cycling Injuries Emergency department

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Slicing capacity-centered mode selection and resource optimization for network-assisted full-duplex cell-free distributed massive MIMO systems

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Science China(Information Sciences) 2024年第1期67卷 203-220页

作者： jie WANG Jiamin LI Pengcheng ZHU Dongming WANG Hongbiao ZHANG Yue HAO Bin sheng National Mobile Communications Research Laboratory Southeast University 2. Purple Mountain Laboratories China Mobile Research Institute

Network-assisted full-duplex(NAFD) cell-free distributed massive multiple-input multipleoutput(MIMO) systems enable uplink(UL) and downlink(DL) communications within the same timefrequency resources,which potentially reduce latency by avoiding the overhead of switching UL/DL ***,how to choose UL/DL modes remains an important factor affecting system *** the dramatic increase in the number of users and access points(APs),massive access brings significant overhead in the mode ***,the different quality of service(QoS) among users also makes the effective utilization of resources *** one of the most promising technologies in sixth-generation(6G),network slicing enables the adaptive configuration of limited UL/DL resources through the resource isolation assisted NAFD ***,we propose a slicing capacity-centered *** this scheme,APs are motivated by slicing requirements and associated slices to form different *** mode selection and resource allocation are performed within each subsystem to reduce overhead and improve resource *** implement this scheme efficiently,a double-layer deep reinforcement learning(DRL)mechanism is used to realize the joint optimization of mode selection and resource *** results show that the slicing capacity-centered scheme can effectively improve resource utilization and reduce overhead.

关键词： network-assisted full-duplex network slicing mode selection resource optimization deep reinforcement learning

Hydrogen-rich surface of MoC catalysts for efficient CO_(2)hydrogenation induced by a coupled hydrogen donator

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Nano Research 2024年第8期17卷 7762-7767页

作者： Dong Xu Si-Yuan Xia Qi-Yuan Li jie-sheng Chen Xin-Hao Li School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

Direct CO_(2)hydrogenation offers an important strategy for promoting the global carbon balance,but high thermodynamic and kinetic stability of CO_(2)has restricted its applicability to only a handful of industrial ***,we introduce a proof-of-concept application of the electron-rich Pt surface to promote hydrogen donation for electron-rich MoC particles acting as hydrogen acceptors,thereby constructing hydrogen-rich surface of MoC active ***,the formed hydrogen-rich and electronrich surface could greatly decrease reaction activation energy to boost the efficient CO_(2)hydrogenation into formic acid over the MoC *** optimized MoC@NC/Pt-0.1(NC:nitrogen-doped carbon)catalyst exhibits a high turnover frequency(TOF)value of 1.2 h^(−1) at a lower temperature of 60℃and a TOF of 24.2 h^(−1) under standard reaction conditions widely used in the literature,exceeding 7 times of MoC@NC catalyst and surpassing the benchmark classical non-noble metal active center-based heterogeneous catalyst.

关键词： electron-rich Pt nanoparticles hydrogen donation hydrogen-rich MoC nanoparticles CO_(2)hydrogenation formic acid

Féeton(B-L gauge boson)dark matter for the 511-keV gamma-ray excess and the prediction of low-energy neutrino flux

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Chinese Physics C 2024年第8期48卷 76-82页

作者： jie sheng Yu Cheng Weikang Lin Tsutomu T.Yanagida Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityChina Key Laboratory for Particle Astrophysics and Cosmology(MOE)&Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong UniversityShanghai 200240China South-Western Institute For Astronomy Research Yunnan UniversityKunming 650500China Kavli IPMU(WPI) UTIASUniversity of TokyoKashiwa277-8583Japan

The féeton is the gauge boson of the U(1)_(B−L) gauge *** the gauge coupling constant is extremely small,the féeton becomes a candidate for dark *** show that its decay to a pair of an electron and a positron explains the observed Galactic 511-keV gamma-ray excess in a consistent *** féeton dark matter decays mainly into pairs neutrino and *** low-energy experiments with improved directional capability will enable capturing these neutrino *** seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparable to the current cosmological constraint.

关键词： feeton 511-keV gamma-ray excess low-energy neutrino

Early detection of multiple endocrine neoplasia type 1: A case report

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World Journal of Gastroenterology 2024年第26期30卷 3247-3252页

作者： jie-Hao Yuan Su Luo Ding-Guo Zhang Li-sheng Wang Department of Gastroenterology Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan University)Shenzhen 518020Guangdong ProvinceChina

BACKGROUND Multiple endocrine neoplasias(MENs)are a group of hereditary diseases invol-ving multiple endocrine glands,and their prevalence is *** type 1(MEN1)has diverse clinical manifestations,mainly involving the parathyroid glands,gastrointestinal tract,pancreas and pituitary gland,making it easy to miss the clinical *** SUMMARY We present the case of a patient in whom MEN1 was detected early.A middle-aged male with recurrent abdominal pain and diarrhea was admitted to the *** tests at admission revealed hypercalcemia and hypophosphatemia,and emission computed tomography of the parathyroid glands revealed a hy-perfunctioning parathyroid *** findings suggested a duodenal bulge and *** endoscopy revealed a hypoechoic lesion in the duodenal *** blood tests revealed elevated levels of serum *** was performed,and pathological analysis of the surgical specimens revealed a parathyroid adenoma after parathyroidectomy and a neuroendocrine tumor after duodenal *** time from onset to the definitive diagnosis of MEN1 was only approximately 1 *** For patients who present with gastrointestinal symptoms accompanied by hyper-calcemia and hypophosphatemia,clinicians need to be alert to the possibility of MEN1.

关键词： Multiple endocrine neoplasia type 1 Gastrointestinal symptoms Hypercal-cemia Early detection Case report

High-temperature oxidation resistance of Si-coated C/SiC composites

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Rare Metals 2024年第9期43卷 4566-4572页

作者： jie Xiao Hua-Yue Zhang sheng-Kai Gong Hui-Bin Xu Hong-Bo Guo School of Materials Science and Engineering Beihang University Key Laboratory of High-Temperature Structure Materials and Protective Coatings (Ministry of Industry and Information Technology) Beihang University

In this paper, Si coatings were sprayed onto C/Si C composite substrates by atmospheric plasma spraying(APS). The high-temperature oxidation behavior of the substrate and coating at temperatures of 1100 and 1300 °C was also studied. The C/Si C ceramic matrix composite will be damaged seriously and even failed due to the oxidation of carbon fibers in matrix. The Si coating effectively improved the oxidation resistance of the C/Si C substrate in the high-temperature oxidation test. The effect of the thickness of the Si coatings on the oxidation resistance was investigated. The 150-μm coating is proved to enable the substrate to have the lowest oxidation weight loss and the best oxidation resistance after static oxidation for 5 h.

关键词： Carbon fiber Ceramic matrix composites (CMCs) Oxidation Plasma spray Si coating