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Barrier Option Pricing in Regime Switching Models with Rebates

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 849-861页

作者： yue-xu zhao Jia-yong BAO School of Economics Hangzhou Dianzi UniversityHangzhou 310018China School of Sciences Hangzhou Dianzi UniversityHangzhou 310018China

This paper is concerned with the valuation of single and double barrier knock-out call options in a Markovian regime switching model with specific *** integral formulas of the rebates are derived via matrix Wiener-Hopf factorizations and Fourier transform techniques,also,the integral representations of the option prices are ***,the first-passage time density functions in two-state regime model are *** applications,several numerical algorithms and numerical examples are presented.

关键词： option pricing Markovian regime switching Wiener-Hopf factorization Fourier transform

Adverse effects of exposure to fine particles and ultrafine particles in the environment on different organs of organisms

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Journal of Environmental Sciences 2024年第1期135卷 449-473页

作者： Jianwei Zhang zhao Chen Dan Shan Yang Wu yue zhao Chen Li yue Shu Xiaoyu Linghu Baiqi Wang Department of Occupational and Environmental Health School of Public HealthTianjin Medical UniversityTianjin 300070China Department of Medical Tianjin Stomatological HospitalSchool of MedicineNankai UniversityTianjin 300041China Tianjin Key Laboratory of Environment Nutrition and Public HealthTianjin 300070China National Demonstration Center for Experimental Preventive Medicine Education(Tianjin Medical University) Tianjin 300070China

Particulate pollution is a global risk factor that seriously threatens human *** particles(FPs)and ultrafine particles(UFPs)have small particle diameters and large specific surface areas,which can easily adsorb metals,microorganisms and other *** and UFPs can enter the human body in multiple ways and can be easily and quickly absorbed by the cells,tissues and *** the body,the particles can induce oxidative stress,inflammatory response and apoptosis,furthermore causing great adverse *** studies mainly take the population as the research object to study the distribution of diseases and health conditions in a specific population and to focus on the identification of influencing ***,the mechanism by which a substance harms the health of organisms is mainly demonstrated through toxicological *** epidemiological studies with toxicological studies will provide a more systematic and comprehensive understanding of the impact of PM on the health of *** this review,the sources,compositions,and morphologies of FPs and UFPs are briefly introduced in the first *** effects and action mechanisms of exposure to FPs and UFPs on the heart,lungs,brain,liver,spleen,kidneys,pancreas,gastrointestinal tract,joints and reproductive system are systematically *** addition,challenges are further pointed out at the end of the *** work provides useful theoretical guidance and a strong experimental foundation for investigating and preventing the adverse effects of FPs and UFPs on human health.

关键词： Fine particles Ultrafine particles Organs Adverse effect

CuInS_(2)quantum-dot-modified g-C_(3)N_(4)S-scheme heterojunction photocatalyst for hydrogen production and tetracycline degradation

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Journal of Materials Science & Technology 2024年第5期172卷 145-155页

作者： Jingjing Zhang yue zhao Kezhen Qi Shu-yuan Liu College of Pharmacy Dali UniversityDali 671000China Department of Pharmacology Shenyang Medical CollegeShenyang 110034China

CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth *** as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption *** photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light *** optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN *** enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional *** work is an effort to adjust CN-based polysulfide QD for speedy *** enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.

关键词： CuInS_(2)QDs g-C_(3)N_(4) Photocatalysis Hydrogen production S-scheme heterojunction

Recent research progress in the mechanism and suppression of fusion welding-induced liquation cracking of nickel based superalloys

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1072-1088页

作者： Zongli Yi Jiguo Shan yue zhao Zhenlin Zhang Aiping Wu Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China College of Engineering China Agricultural UniversityBeijing 100091China State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China School of Material Science and Engineering Southwest Jiaotong UniversityChengdu 610031China

Nickel-based superalloys are extensively used in the crucial hot-section components of industrial gas turbines,aeronautics,and astronautics because of their excellent mechanical properties and corrosion resistance at high *** welding serves as an effective means for joining and repairing these alloys;however,fusion welding-induced liquation cracking has been a challenging *** paper comprehensively reviewed recent liquation cracking,discussing the formation mechanisms,cracking criteria,and *** recent investigations,regulating material composition,changing the preweld heat treatment of the base metal,optimizing the welding process parameters,and applying auxiliary control methods are effective strategies for mitigating *** promote the application of nickel-based superalloys,further research on the combination impact of multiple elements on cracking prevention and specific quantitative criteria for liquation cracking is necessary.

关键词： nickel-based superalloy fusion welding liquation cracking cracking mechanism cracking suppression

Smart Gait:A Gait Optimization Framework for Hexapod Robots

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 146-159页

作者： Yunpeng Yin Feng Gao Qiao Sun yue zhao Yuguang Xiao State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Lenovo Corporation ShanghaiChina AI Institute School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The current gait planning for legged robots is mostly based on human presets,which cannot match the flexible characteristics of natural *** paper proposes a gait optimization framework for hexapod robots called Smart *** Gait contains three modules:swing leg trajectory optimization,gait period&duty optimization,and gait sequence *** full dynamics of a single leg,and the centroid dynamics of the overall robot are considered in the respective *** Smart Gait not only helps the robot to decrease the energy consumption when in locomotion,mostly,it enables the hexapod robot to determine its gait pattern transitions based on its current state,instead of repeating the formalistic clock-set step *** Smart Gait framework allows the hexapod robot to behave nimbly as a living animal when in 3D movements for the first *** Smart Gait framework combines offline and online optimizations without any fussy data-driven training procedures,and it can run efficiently on board in real-time after *** experiments are carried out on the hexapod robot *** results show that the energy consumption is reduced by 15.9%when in *** gait patterns can be generated spontaneously both in regular and challenge environments,and when facing external interferences.

关键词： Gait optimization Swing trajectory optimization Legged robot Hexapod robot

Improvement for creep strength of a second-generation single crystal superalloy by design of heat treatments

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Rare Metals 2024年第1期43卷 342-350页

作者： Wan-Shun Xia Xin-Bao zhao Jia-Chen Xu Quan-zhao yue Qing-Qing Ding Huan-Chang Duan yue-Feng Gu Hong-Bin Bei Ze Zhang Institute of Superalloys Science and Technology School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Silicon and Advanced Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

Design of heat treatments is related to the key technology for development of nickel-based single crystal superalloys(Ni-SXs). Based on the full understanding of the solidification characteristics, this work applies optimization design of heat treatments for a second-generation Ni-SX. Microstructure evolution and creep properties are compared in the material under conventional/standard(Std.) and optimized(Opt.) treatments. For the Std. sample,strong dendritic segregations determine inconsistent microstructure evolution in the dendritic(D) and interdendritic region(ID), while the latter serves as weak area to have the prior microcrack initiation, damaging overall performance of the alloy. The Opt. treatment applies higher homogenization temperature, leading to overall reduced segregations, while not inducing incipient melting. A lower temperature of first-step ageing is used to lower the size ofγ'particles. These help to form the more uniform microstructure in dendritic and interdendritic region and relieve the inconsistent microstructure evolution. The balanced local strength makes ID no longer as the weak area,thus restricting microcrack initiation. Great improvement of high temperature and low stress property is obtained by this progress, leading to the pronounced increase of creep rupture life under 1100 °C/140 MPa.

关键词： Single crystal superalloy Heat treatment Segregation Solidification Creep property

Lath-like phases formed at an extremely high temperature in a Mg-RE(RE=rare earth)-Al alloy

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Rare Metals 2024年第8期43卷 3937-3945页

作者： Bo Deng Shu-Hui Lv Qiang Yang Dong-yue zhao Jun-Yuan Fan Xin Qiu School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Chongqing Research Institute Changchun University of Science and TechnologyChongqing 401135China

Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)*** this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at 873 ***-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM) characterizations indicate that most of them are Mg-containing Al_(2)(Gd,Sm),with the atomic ratio of Mg:Al:(Gd,Sm) being ~1:1:1;a small part of them with relatively wider thickness are long-period stacking ordered(LPSO) phases simultaneously containing both 14H and 18R *** followed common orientation relationships with Mg matrix as those reported in previous *** addition,many Mg laths were observed in the primary blocky Al_(2)(Gd,Sm) phase at grain boundaries,where the atomic ratio of Al:(Gd,Sm) in the Al_(2)(Gd,Sm) matrix was 2:***,density functional theory(DFT) calculations illustrated the detail structure of the re-constructed Mg/Al_(2)RE interface and simultaneously deduced the underlying reason for the re-dissolution of the newly formed Mg-containing Al_(2)(Gd,Sm) plates in α-Mg matrix.

关键词： Magnesium alloy HAADF-STEM Microstructures Intermetallic particles Orientation relationships Interfaces

Food poisoning due to money tree seeds:a case report of toxic encephalopathy

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Emergency and Critical Care Medicine 2024年第3期4卷 126-129页

作者： yue zhao Xiaojiao Quan Tao Wang Department of Emergency Medicine Hainan Hospital of Chinese PLA General HospitalSanyaHainanChina The Center of Heat Stroke Prevention and Treatment of Peoples’Liberation Army SanyaHainanChina

Background:The money tree is a favored indoor potted plant in *** seeds resemble chestnuts in both shape and flavor when cooked,which are generally considered non-toxic and safe for *** presentation:This report presents the first published case of food poisoning due to the ingestion of large amounts of money tree seeds.A 67-year-old man exhibited toxic encephalopathy symptoms and dyspnea after consuming the seeds for approximately 6 *** empirical mechanical ventilation,therapeutic plasma exchange,and other medical interventions,the patient’s clinical status improved *** was subsequently discharged from the ***:Consuming a substantial quantity of money tree seeds within a limited timeframe can lead to poisoning,resulting in adverse outcomes,particularly toxic ***,plasma exchange may have some therapeutic effect.

关键词： Case report Money tree Pachira macrocarpa Respiratory failure Toxic encephalopathy

Geometry characteristics and wide temperature behavior of silicon-based GaN surface acoustic wave resonators with ultrahigh quality factor

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Science China(Information Sciences) 2024年第2期67卷 267-278页

作者： Guofang YU Renrong LIANG Haiming zhao Lei XIAO Jie CUI yue zhao Wenpu CUI Jing WANG Jun XU Jun FU Tianling REN School of Integrated Circuits Tsinghua University Beijing National Research Center for Information Science Technology Tsinghua University

Surface acoustic wave(SAW) resonators with an ultrahigh Q-factor are designed and fabricated on silicon-based gallium nitride(GaN/Si). The temperature-dependent performance is characterized over a wide range, from 10 to 500 K. Finite element analysis is employed to guide the design of the SAW resonator from indications of the Rayleigh mode and weak propagation direction dependence of SAW in the c-plane of GaN/Si. The SAW resonator with 100 pairs of interdigital transducers(IDT), 100 pairs of grating reflectors(GR) for each side, aperture size of 80 μm, metallization ratio of 0.5, and electrode width of 500 nm resonates at 1.9133 GHz accordingly with an ultrahigh Q-factor of 7622 at room temperature, which contributes the fr× Qr, up to 14.583×1012Hz. A resonator operating over 10 to 500 K indicates an approximately linear decreasing temperature dependence above 280 K while being approximately constant below 40 K. The fitting to resonator characteristics using the modified Butterworth Van Dyke(m BVD) model reveals a reduction in both the electrode and mechanical losses while worsening the dielectric loss with cooling down.

关键词： GaN/Si SAW resonator ultrahigh Q-factor temperature-dependent performance mBVD losses