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Rare Metals 2019年第9期38卷 824-831页

作者： yao-mian wang Wei Zhuang Huan-Ping Yang Cong-Hui Zhang School of Metallurgical Engineering Xi’an University of Architecture and Technology

Commercially pure zirconium was processed by the surface mechanical attrition treatment(SMAT),and the microstructure observation showed that a gradient structure was *** measurements were taken to obtain the load-displacement curves at different depths below the treated *** dimensional analysis,the local yield stress,hardness,strain hardening exponent,and elastic modulus at the corresponding depths were *** results showed that the yield stress and hardness varied with depth,while the strain hardening exponent and elastic modulus were approximately *** finite element method was used to simulate nanoindentation at different depths below the treated surface to verify the derivation of the local elastic-plastic constitutive *** curves were computed for the treated samples through the rule of mixtures,and they agreed well with the experimental *** analysis showed that the surface and subsurface hardening layers as well as the transition layer shared a high load applied to the samples,even though their volume fraction was small.

关键词： Mechanical property Severe plastic deformation Gradient microstructure Nanoindentation Finite element method

Statistical inference for the nonparametric and semiparametric hidden Markov model via the composite likelihood approach

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Science China Mathematics 2023年第3期66卷 601-626页

作者： mian Huang Yue Huang Weixin yao School of Statistics and Management Shanghai University of Finance and EconomicsShanghai 200433China Department of Statistics University of CaliforniaRiversideRiversideCA 92521USA

In this paper, we propose a new estimation method for a nonparametric hidden Markov model(HMM), in which both the emission model and the transition matrix are nonparametric, and a semiparametric HMM, in which the transition matrix is parametric while emission models are nonparametric. The estimation is based on a novel composite likelihood method, where the pairs of consecutive observations are treated as independent bivariate random variables. Therefore, the model is transformed into a mixture model, and a modified expectation-maximization(EM) algorithm is developed to compute the maximum composite *** systematically study asymptotic properties for both the nonparametric HMM and the semiparametric HMM. We also propose a generalized likelihood ratio test to choose between the nonparametric HMM and the semiparametric HMM. We derive the asymptotic distribution and prove the Wilk’s phenomenon of the proposed test statistics. Simulation studies and an application in volatility clustering analysis of the volatility index in the Chicago Board Options Exchange(CBOE) are conducted to demonstrate the effectiveness of the proposed methods.

关键词： nonparametric HMM nonhomogeneous HMM semiparametric estimate composite likelihood generalized likelihood ratio test

How the radial gap affects the runner’s hydrodynamic damping characteristic of a pump-turbine:A physical experiment on a rotating disc

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Journal of Hydrodynamics 2023年第4期35卷 736-745页

作者： Yong-shun Zeng Xin Qi mian-mian Bai Ling-jiu Zhou Zhi-feng yao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China BAPTEEC LTD Beijing100176China Shanxi Province Institute of Water Resources and Electric Power Investigation and Design Xi’an710001China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing100083China

Clarifying how radial gap affects the vibration characteristic of a disc-like structure is of importance in engineering applications,such as in evaluating the operational stability of a runner of a pump *** the present investigation,the runner is simplified as a disc,and a physical experiment is designed on it with variable radial gaps to measure the vibration characteristics,especially by considering *** frequency peaks for the diametrical mode are generated due to the rotation,and those with lower and higher frequencies are defined as positive and negative modes,*** frequency difference between positive and negative modes increases linearly with the increasing rotating speed,and a linear function is captured to describe the relationship between natural frequency and rotating *** the radial gap,its increase causes a slight increase in the natural frequencies but results in a significant reduction in the hydrodynamic damping *** in the smaller radial gap conditions,such as when the relative radial gap increases from 0.67%to 3.3%,the reduction in hydrodynamic damping ratio reaches 31.52%.From the perspective of suppressing the resonance amplitude,reducing the radial gap of a runner is recommended due to the mechanism of increasing hydrodynamic damping.

关键词： Rotating disc radial gap rotating speed natural frequency hydrodynamic damping

Effect of mechanical alloying on sinterability and phase evolution in pressure-less sintered TiB_(2)-TiC ceramics

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Journal of Materiomics 2019年第4期5卷 670-678页

作者： Tian-Yi Hu mian-Yi yao Dong-Li Hu Hui Gu Yu-Jin wang Materials Genome Institute School of Materials Science and EngineeringShanghai UniversityShanghai200444China Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of Technology150080China Key Laboratory of Advanced Structure Function Integrated Materials and Green Manufacturing TechnologyMinistry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin150001China

Phase relation and microstructure evolution in the pressure-less sintered TiB_(2)‒TiC ceramics preceded with mechanical alloying were systematically studied by a combination of SEM *** debris from milling balls promotes sintering by dissolving into the TiC phase to achieve dense microstructures at 1600℃.Variation of W solution in TiC grains exposes two types of core-rim structures,with no or more W in dark and white cores respectively but with common medium W in both *** whitecores reveal an exchange reaction between WC and TiC via mechanical alloying to form the Ti_(1-z)W_(z)C phase prior to *** dark-cores inherit from the as-milled TiC power to further enable the reprecipitation of rims from a mixed liquid-phase,which facilitated also the anisotropic growth of TiB_(2) *** dark-cores grow persistently in the second-step at 2000℃ enabled by this liquid-phase,which coarsens the TiB2 grains *** more alloyed phase,sintering was insufficient at 1500℃ with only the surface fluidity from the primary powders,and the second-step sintering increased the fluidity in the liquid-phase to fully densify the binary ***-distribution of the alloyed W by two-step sintering rationalizes the evolution process of the binary microstructures and leads to better understanding of the mechanical behaviors.

关键词： TiB2‒TiC ceramics Mechanical alloying Core‒rim structures Liquid-phase sintering Microstructure‒Property relationship

Magnetostratigraphy and ^(230)Th dating of a drill core from the southeastern Qaidam Basin:Salt lake evolution and tectonic implications

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Geoscience Frontiers 2018年第3期9卷 943-953页

作者： An-Dong Chen mian-Ping Zheng Hai-Tao yao Kui Su Jian-Ming Xu MLR Key Laboratory of Saline Lake Resources and Environments Institute of Mineral ResourcesChinese Academy of Geological Sciences Institute of Geomechanics Chinese Academy of Geological Sciences

The Qarhan Salt Lake area is the Quaternary depocenter of the Qaidam Basin, and carries thick lacustrine sediments, as well as rich potassium and magnesium salt deposits. The abundant resources and thick sediments in this lake provide an ideal place for the study of biogas formation and preservation, salt lake evolution, and the uplift of the Tibetan Plateau. In this study, we attempt to construct a paleomagnetic and ^(230)Th age model and to obtain information on tectonic activity and salt lake evolution through detailed studies on a 1300-m-long drill core(15DZK01) from the northwestern margin of the Qarhan Salt Lake area(Dongling Lake). Based on gypsum ^(230)Th dating, the age of the uppermost clastic deposit was calculated to be around 0.052 Ma. The polarity sequence consist of 13 pairs of normal and reversed zones,which can be correlated with subchrons C2r.1r-C1n of the geomagnetic polarity timescale(GPTS 2012)(from ~2.070 Ma to ~0.052 Ma). Sedimentary characteristics indicate that Dongling Lake witnessed freshwater environment between ~ 2.070 Ma and 1.546 Ma. During this period, the sedimentary record reflects primarily lakeshore, shallow-water and swamp environments, representing favourable conditions for the formation of hydrocarbon source rocks. Between 1.546 Ma and ~ 0.052 Ma, the Dongling Lake was in sulphate deposition stage, which contrasts with the central Qarhan Salt Lake area, where this stage did not occur in the meantime. During this stage, Dongling Lake was in a shallow saltwater lake environment, but several periods of reduced salinity occurred during this stage. During the late Pleistocene at ~0.052 Ma, the Dongling Lake experienced uplift due to tectonic activity, and saltwater migrated through the Sanhu Fault to the central Qarhan Salt Lake area, resulting in the absence of halite deposition stage. The residual saline water was concentrated into magnesium-rich brine due to the lack of freshwater, and few potassium salt deposits occur in the Don

关键词： Qaidam Basin Magnetostratigraphy 230Th dating Salt lake evolution Tectonic activity

Chinese Herbal Medicine for Osteosarcoma in the Mouse: A Systematic Review and Meta-Analysis

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Chinese Journal of Integrative Medicine 2019年第5期25卷 370-377页

作者： CHANG Jun-li wang Wen-yi LI Yi-mian HU Shao-pu yao Min CUI Xue-jun ZHI Wen-lan SHI Qi wang Yong-jun YANG Yan-ping Orthopedic Surgery Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai(200032)China Institute of Spine Shanghai University of Traditional Chinese MedicineShanghai(200032)China

Objective: To summarize and critically assess the inhibitory effects of Chinese herbal medicine(CHM) on tumor volume and tumor weight for the treatment of osteosarcoma(OS) in mouse models. Methods:PubMed, Embase, Web of Science, China Knowledge Resource Integrated Database(CNKI), Wanfang Database, VIP Database, and Chinese BioMedical(CBM) were searched since their inception dates to March10, 2016. Two reviewers independently selected the controlled studies estimating effects of CHM on mouse OS by administration in vivo. A pair-wise meta-analysis was performed. Twenty-five studies with adequate randomization were included in the systematic review. Results: CHM may signi?cantly inhibit OS growth in mice, as assessed using the tumor weight [20 studies, n=443; 290 for CHM and 153 for the control; pooled mean difference(MD)=–2.90; 95% confidence interval(CI): –3.50 to –2.31; P<0.01], tumor volume(16 studies, n=382; 257 for CHM and 125 for the control; pooled MD =–2.57; 95% CI: –3.33 to –1.80; P<0.01) and tumor growth inhibition rate. Conclusion: CHM could significantly inhibit the growth of OS in mouse models,which might be supportive for the design of preclinical and clinical trials in future.

关键词： Chinese herbal medicine osteosarcoma systematic review meta-analysis mouse xenograft model

No-reference noisy image quality assessment incorporating features of entropy, gradient, and kurtosis

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Frontiers of Information Technology & Electronic Engineering 2021年第12期22卷 1565-1582页

作者： Heng yao Ben MA mian ZOU Dong XU Jincao yao School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China Cancer Hospital of the University of Chinese Academy of Sciences(Zhejiang Cancer Hospital) Hangzhou 310000China Institute of Basic Medicine and Cancer Chinese Academy of SciencesHangzhou 310000China

Noise is the most common type of image distortion affecting human visual *** this paper,we propose a no-reference image quality assessment(IQA)method for noisy images incorporating the features of entropy,gradient,and ***,image noise estimation is conducted in the discrete cosine transform domain based on skewness *** the principal component analysis domain,kurtosis feature is obtained by statistically counting the significant differences between images with and without *** addition,both the consistency between the entropy and kurtosis features and the subjective scores are improved by combining them with the gradient *** vector regression is applied to map all extracted features into an integrated scoring *** proposed method is evaluated in three mainstream databases(i.e.,LIVE,TID2013,and CSIQ),and the results demonstrate the superiority of the proposed method according to the Pearson linear correlation coefficient which is the most significant indicator in IQA.

关键词： Noisy image quality assessment Noise estimation Kurtosis Human visual system Support vector regression

Development of septic shock and prognostic assessment in critically ill patients with coronavirus disease outside Wuhan, China

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World Journal of Emergency Medicine 2021年第4期12卷 293-298页

作者： Ren-qi yao Chao Ren Di Ren Jin-xiu Li Ying Li Xue-yan Liu Lei Huang Yong Liu mian Peng Yong-wen Feng Yong-ming yao Department of Critical Care Medicine the Second People’s Hospital of ShenzhenShenzhen 518035China Trauma Research Center the Fourth Medical Center and Medical Innovation Research Department of the Chinese PLA General HospitalBeijing 100048China Department of Critical Care Medicine the Third People’s Hospital of ShenzhenShenzhen 518020China Department of Critical Care Medicine the People’s Hospital of ShenzhenShenzhen 518020China Department of Critical Care Medicine Peking University Shenzhen HospitalShenzhen 518035China Department of Critical Care Medicine Shenzhen Hospital of Southern Medical UniversityShenzhen 518110China Department of Critical Care Medicine the Third Affiliated Hospital of Shenzhen UniversityShenzhen 518001China

BACKGROUND: The study aims to illustrate the clinical characteristics and development of septic shock in intensive care unit(ICU) patients confirmed with severe acute respiratory syndrome coronavirus 2(SARS-Co V-2) infection, and to perform a comprehensive analysis of the association between septic shock and clinical outcomes in critically ill patients with coronavirus disease(COVID-19).METHODS: Patients confirmed with SARS-Co V-2 infection, who were admitted to the ICU of the Third People's Hospital of Shenzhen from January 1 to February 7, 2020, were enrolled. Clinical characteristics and outcomes were compared between patients with and without septic ***: In this study, 35 critically ill patients with COVID-19 were included. Among them, the median age was 64 years(interquartile range [IQR] 59-67 years), and 10(28.4%) patients were female. The median ICU length of stay was 16 days(IQR 8-23 days). Three(8.6%) patients died during hospitalization. Nine(25.7%) patients developed septic shock in the ICU, and these patients had a significantly higher incidence of organ dysfunction and a worse prognosis than patients without septic ***: Septic shock is associated with a poor outcome in critically ill COVID-19 patients and is one of the hallmarks of the severity of patients receiving ICU care. A dysregulated immune response, uncontrolled infl ammation, and coagulation disorders are strongly associated with the development and progression of COVID-19-related septic shock.

关键词： Severe acute respiratory syndrome coronavirus 2 Coronavirus disease Intensive care unit Septic shock Immune response

In-situ growth of MAX phase coatings on carbonised wood and their terahertz shielding properties

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Journal of Advanced Ceramics 2021年第6期10卷 1291-1298页

作者： Jiaxuan HUANG Hujie WAN mian LI Yiming ZHANG Jianfeng ZHU Xuelin LI Wenchao SHUI yao LI Xiaomeng FAN Qiye WEN Xu XIAO Qing HUANG School of Shaanxi University of Science and Technology Xi’an 710021China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Qianwan Institute of CNiTECH Zhongchuangyi RoadHangzhou Bay DistrictNingbo 315336China School of Electronic Science and Engineering State Key Laboratory of Electronic Thin Film and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengdu 610054China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Poly technical UniversityXi’an 710072China

Electromagnetic interference(EMI)shielding materials have received considerable attention in recent *** EMI shielding effectiveness(SE)of materials depends on not only their composition but also their *** various microstructure prototypes,porous structures provide the advantages of low density and high terahertz wave *** this study,by using carbonised wood(CW)as a template,1-mm-thick MAX@CW composites(Ti2AlC@CW,V2A1C@CW,and Cr2AlC@CW)with a porous structure were fabricated through the molten salt *** MAX@CW composites led to the formation of a conductive network and multilayer interface,which resulted in improved EMI *** average EMI SE values of the three MAX@CW composites were>45 dB in the frequency of 0.6-1.6 *** the composites,V2A1C@CW exhibited the highest average EMI SE of 55 dB.

关键词： MAX phases biomimics electromagnetic interference(EMI) terahertz shielding

Diabetes mellitus with hepatic infarction: A case report with literature review

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World Journal of Gastroenterology 2006年第31期12卷 5091-5093页

作者： Yong-Gui Deng Zhan-Sheng Zhao mian wang Sheng-Ou Su Xi-Xian yao Department of Endocrinology The Second Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China

Hepatic infarction rarely occurs due to the double supply of arterial and portal inflow. A 53-year-old man with diabetes mellitus developed multiple hepatic infarctions after an episode of fever and diarrhea. The infarction was documented by pathology after partial liver resection. Several causes of hepatic infarction may present in this patient： dehydration and hypotension caused by fever and diarrhea, type 2 diabetes and administration of glibenclamide, diabetic ketoacidosis and widespread atherosderosis. We suggest that diabetic patient with elevated liver enzyme should be considered the possibility of hepatic infarction.

关键词： Diabetes mellitus Hepatic infarction Computerized tomography