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Reproducibility of optical quality parameters measured at objective and subjective best focuses in a doublepass system

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 1043-1050页

作者： Ai-Lian Hu Li-Ya Qiao Ye Zhang xiao-gu cai Lei Li Xiu-Hua Wan Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology & Vision Science Key Lab

AIMTo evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass *** Chinese healthy adults (19 to 40 years old) meeting our inclusion criterion were enrolled in the study. After a basic eye examination, two methods of optical quality measurement, based on subjective and objective best focuses were performed using the Optical Quality Analysis System (OQAS) with an artificial pupil diameter of 4.0 *** each method, three consecutive measurements of the following parameters: the modulation transfer function cutoff frequency (MTFcutoff), the Strehl2D ratio, the OQAS values (OVs) at contrasts of 100%, 20%, 9% and the objective scatter index (OSI) were performed by an experienced examiner. The repeatability of each method was evaluated by the repeatability limit (RL) and the coefficient of repeatability (COR). Reproducibility of the two methods was evaluated by intra-class correlation coefficient (ICC) and the 95% limits of agreement (Bland and Altman analysis). Thirty subjects, seven females and twenty three males, of whom 15 right eyes and 15 left eyes were selected randomly for recruitment in the study. The RLs (percentage) for the six parameters measured at objective focus and subjective focus ranged from 8.44% to 15.13% and 10.85% to 16.26%, respectively. The CORs for the two measurement methods ranged from 8.27% to 14.83% and 10.63% to 15.93%, respectively. With regard to reproducibility, the ICCs for the six parameters of OQAS ranged from 0.024 to 0.276. The 95% limits of agreement obtained for the six parameters (in comparison of the two methods) ranged from -0.57 to 42.18 (MTFcutoff), -0.01 to 0.23 (Strehl2D ratio), -0.02 to 1.40 (OV100%), -0.10 to 1.75 (OV20%), -0.14 to 1.80 (OV9%) and -1.46 to 0.18 (OSI).CONCLUSIONMeasurements provided by OQAS with either method sh

关键词： optical quality double-pass system best focus repeatability reproducibility

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Analysis of China's Electricity Price and Electricity Burden of Basic Industries under the Carbon Peak Target before 2030

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 481-491页

作者： Yue Qiu Suyang Zhou Wei gu xiao-Ping Zhang School of Electrical Engineering Southeast UniversityNanjingChina School of Electronic Electrical and System EngineeringUniversity of BirminghamU.K.

The Chinese government is deepening reformation of electricity prices during the 14th Five Year Plan period and has set a carbon emission reduction target of reaching carbon peak before *** this context,will the carbon emission target influence electricity pricing and will electricity price influence competitiveness of Chinese main industries are two questions needing to be *** paper compares China's electricity price level with the selected major countries in the world,and four typical industries are selected to evaluate their electricity burden ***,the correlation between residential electricity price and industrial electricity price and the influencing factors is analyzed,from the perspectives of scale,structure and *** to the model obtained by regression analysis,the electricity price level and corresponding residential and industrial electricity burden in 2025 and 2030 are *** Terms-Electricity burden,industrial electricity price,regression analysis,residential electricity price.

关键词： Electricity burden industrial electricity price regression analysis residential electricity price

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Systematic Evaluation of guidelines for the Diagnosis and Treatment of Hepatitis E Virus Infection

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Journal of Clinical and Translational Hepatology 2024年第8期12卷 739-749页

作者： Ting gu cai-Ying Zheng Yan-Qin Deng xiao-Feng Yang Wei-Min Bao Ying-Mei Tang Department of Gastroenterology Second Affiliated Hospital of Kunming Medical UniversityKunming Medical UniversityKunmingYunnanChina Second Affiliated Hospital of Kunming Medical University KunmingYunnanChina Department of Colorectal Surgery The First People’s Hospital of Yunnan ProvinceKunmingYunnanChina

Background and Aims:The hepatitis E virus(HEV)is a zoonotic disease,and infection with HEV in humans primarily causes acute infections and can progress to chronic manifestation in immunocompromised *** the past decade,guidelines for diagnosing and treating HEV infection have been *** study aimed to systematically assess the quality of current guidelines for diagnosing and treating HEV infection,and we analyzed the differences in guideline quality and primary recommendations and explored possible reasons for these ***:guidelines published between 2013 and 2022 were searched,and studies were identified using selection *** study assessed the quality of the included guidelines using the Appraisal of guidelines for Research and Evaluation tool,extracted the primary recommendations in the guidelines,determined the highest level of evidence supporting the recommendations,and reclassified the evidence using the Oxford Centre for Evidence-Based Medicine grading ***:Seven guidelines were included in the final *** quality of the guidelines varied *** discrepancies may have been caused by the lack of external experts,the failure to consider influencing factors in guideline application,and the lack of consideration of the public’s *** of the heterogeneity in primary recommendations revealed differences in algorithms for managing chronic HEV infection,the dosage of ribavirin,and a low level of evidence supporting the primary ***:guideline quality and primary recommendations vary *** by guideline developers and researchers would facilitate updating and applying guidelines for diagnosing and treating HEV infection.

关键词： Hepatitis E virus guidelines Diagnosis Treatment Systematic Evaluation

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A comprehensive fluid-solid coupling dynamic simulation for spatiotemporal distribution of regression rate in hybrid rocket motors

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Chinese Journal of Aeronautics 2024年第9期37卷 100-112页

作者： Tianfang WEI guobiao cai Hui TIAN Xiangyu MENG Xianzhu JIANG xiaoming gu School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of Education Beijing 100191China

The spatiotemporal distribution characteristics of the regression rate are crucial aspects of the research on Hybrid Rocket Motor(HRM).This study presents a pioneering effort in achiev-ing a comprehensive numerical simulation of fluid dynamics and heat transfer in both the fluid and solid regions throughout the entire operation of an *** accomplish this,a dynamic grid tech-nique that incorporates fluid-solid coupling is *** validate the precision of the numerical simulations,a firing test is conducted,with embedded thermocouple probes being used to measure the inner temperature of the fuel *** temperature variations in the solid fuel obtained from both experiment and simulations show good *** maximum combustion temperature and average thrust obtained from the simulations are found to deviate from the experimental results by only 3.3%and 2.4%,***,it can be demonstrated that transient numerical simu-lations accurately capture the fluid-solid coupling characteristics and transient regression *** dynamic simulation results of inner flow field and solid region throughout the entire working stage reveal that the presence of vortices enhances the blending of combustion gases and improves the regression rate at both the front and rear ends of the fuel *** addition,oscillations of the regression rate obtained in the simulation can also be well corresponded with the corrugated surface observed in the ***,the zero-dimension regression rate formula and the for-mula describing the axial location dependence of the regression rate are fitted from the simulation results,with the corresponding coefficients of determination(R°)of 0.9765 and 0.9298,*** research serves as a reference for predicting the performance of HRM with gas oxygen and polyethylene,and presents a credible way for investigating the spatiotemporal distribution of the regression rate.

关键词： Hybrid Rocket Motor(HRM) Transient numerical simulation Fluid-solid couplingheat transfer Spatiotemporal distribution of regression rate Dynamic grid

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A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

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Research in Astronomy and Astrophysics 2024年第6期24卷 191-200页

作者： xiao-gu Zhong Jian-Cheng Wang Yong-Yun Chen xiao-Ling Yu College of Physics and Electronic Engineering Qujing Normal UniversityQujing 655011China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

A possible quasi-periodic oscillation(QPO) at frequency 7.045 × 10^(-5) Hz is found in the narrow-line Seyfert 1galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April *** find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram,the Weighted Wavelet Z-transform and the *** analyze the data in 0.3–0.6 keV,0.6–1 keV,1–3 keV and 3–10 keV energy bands,and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV *** then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^(-5) Hz,and use a model to fit *** find that the QPO signal mainly comes from the X-ray hot corona.

关键词： X-rays:galaxies galaxies:Seyfert accretion accretion disks radiation mechanisms:general

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Highly active and durable core-shell electrocatalysts for proton exchange membrane fuel cells

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Nano Research 2024年第10期17卷 8772-8784页

作者： Hsiwen Wu Fei xiao Jing Wang Meng gu Minhua Shao Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Fok Ying Tung Research Institute The Hong Kong University of Science and TechnologyGuangzhou 511458China Energy Institute and Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution The Hong Kong University of Science and TechnologyClear Water BayHong KongChina

This work presents simple post-treatment methods to selectively and partially remove the Pd core of Pd-Pt core–shell(Pt@Pd/C)*** proton exchange membrane fuel cell with the post-treated Pt@Pd/C cathode(Pt loading:0.10 mg·cm^(-2))delivers an impressive peak power density of 1.2 W·cm^(-2).The partial removal of Pd core endows an ultrahigh oxygen reduction reaction(ORR)mass activity of 0.32 A·g_(PGM)-1 when normalized to the platinum group metal(PGM)mass,or equivalently 0.55 A·mg_(Pt)^(-1) at 0.9 V measured in a fuel *** post-treatment thickens the Pt shells and mitigates the Pd dissolution during potential *** a result,the post-treated core-shell catalyst demonstrates superior durability in ORR mass activity and polarization power density retention than untreated core-shell catalyst and benchmark Pt/***-situ inductively coupled plasmamass spectrometry(ICP-MS)results highlight that the amount of dissolved Pd in post-treated core–shell catalyst is 17-times lower than that of the untreated *** findings highlight the importance of structural tuning of catalysts in enhancing their mass activity and durability.

关键词： core-shell catalyst platinum monolayer proton exchange membrane fuel cell oxygen reduction reaction durability

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Numerical study on the filtration characteristics of fine particles in granular bed filter at high temperature

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Particuology 2024年第10期93卷 41-53页

作者： Kangning Zhu Jie cai Yuan Li xiaoyou Shen Jianfei Xi Yunjun Wang Zhongzhu gu School of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing210023China

Granular bed filter(GBF)has become one of the current research hot topics due to its excellent performance in removing fine *** this paper,a three-dimensional fixed bed GBF filtration model was established and its accuracy was ***,the GBF filtration performance at high temperature were *** results demonstrate that elevating the temperature diminishes the filtration efficiency,albeit to a limited *** increasing of inlet gas velocity can significantly improve pressure drop for GBF and the filtration efficiency for fine particles of sizes larger than 5μ*** the diameter of stacked granular particle diameter grows,the filtration efficiency and pressure drop *** density of fine particles almost does not affect the filtration efficiency for fine particles of 1∼7μm,but a higher density leads to a higher filtration efficiency for fine particles of sizes bigger than 9μ***,as the fine particles size increases,the change of the filtration efficiency roughly goes through three stages:Stage 1:the filtration efficiency is basically unchanged;Stage 2:the filtration efficiency increases rapidly;Stage 3:the filtration efficiency increases steadily,but the rate of increase slows *** the increase of the fine particles Stokes number,the filtration efficiency of GBF will pass through two phases of stabilization and rapid increase.

关键词： Granular bed filter Fine particles High temperature Filtration efficiency

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The Choice of Mesh Size and Integration Points Number for the Electrostatically Controlled Membrane Antenna Structural-Electromagnetic Coupling Model

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Chinese Journal of Electronics 2024年第2期33卷 443-448页

作者： Yongzhen gu Qinggang ZHANG xiao YU guixu LI Qingdao University of Science and Technology

It is of great significance for the improvement of the computational efficiency of the electrostatically controlled membrane antenna(ECMA) structural-electromagnetic coupling model through the choice of appropriate mesh size and integration points number. In this paper, the physical optics formulation is used to analyze the radiation pattern of the ECMA surface, and the finite element method is applied to the electrostatic-structural coupling analysis. An expression for the relation between the mesh size, the focal length of the parabolic antenna, and the wavelength is developed based on the discretization error analysis of the triangular mesh approximating the parabolic surface. Moreover, the integration points number in each triangular mesh is determined by the numerical evaluation of the physical optics integral. Numerical results show that the proposed method improves the computing efficiency by about 87% compared with the referenced method.

关键词： Couplings Surface waves Error analysis Computational modeling Physical optics Numerical models Finite element analysis

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Motivations, Mechanisms, and Paths of Business Model Innovation Driven by the Digital Economy

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Frontiers of Business Research in China 2024年第2期18卷 83-94页

作者： gu Limin ZHANG xiao Institute of Regional Modernization Jiangsu Provincial Academy of Social SciencesNanjing 210004China Business School Nanjing UniversityNanjing 210093China

The digital economy,underpinned by fundamental digital technologies such as artificial intelligence,blockchain,cloud computing,and big data,facilitates business model innovation,thereby enabling firms to achieve distinctive competitive *** the digital economy creates more development opportunities for businesses,it also subjects them to higher levels of competitive ***,business model innovation is both a proactive choice to perceive and exploit external opportunities and a reactive adaptation to identify and mitigate external *** digital economy drives business model innovation through digital information,internet platforms,digital technologies,and new business models and *** such,firms should utilize data resources innovatively to update their value logic,build digital ecosystems based on internet platforms,enhance digital technology integration to enable agile responses,and gain insights into emerging economic formats to promote cross-industry integration and innovation.

关键词： digital economy business model innovation digital information internet platform digitaltechnology

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Chinese Medical Journal 2020年第19期133卷 2308-2314页

作者： Xi-Fang Zhang Li-Ya Qiao xiao-gu cai xiao-Xia Li Jia-Xuan Tan Zheng guan Ye Zhang Kai Cao Ning-Li Wang Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Institute of OphthalmologyBeijing Ophthalmology and Visual Sciences Key LaboratoryBeijing 100730China.

Background:In recent years,visual quality has been extensively investigated in various *** this community-based population study,we analyzed the effects of aging,refraction,and Lens Opacification Classification System III(LOCSIII)score on retinal imaging quality in healthy Chinese ***:This cross-sectional study was conducted on sub-group subjects from The Handan Eye Study between October 2012 and January *** subjects over 30-years-old with logarithm of the minimal angle of resolution(logMAR)best-corrected visual acuity(BCVA)less than 0 were *** image quality was measured by optical quality analysis system(OQAS)and recorded as modulation transfer function cutoff frequency(MTFcutoff),OQAS value(OV)100%,OV20%,OV9%,Strehl ratio(SR),and objective scatter index(OSI).The correlation between age,spherical equivalent refraction(SE),LOCSIII score,and optical quality parameters were investigated by multivariate ***:Among 1108 verified subjects,690 subjects(1380 eyes)met the inclusion *** age ranged from 30 to 76 years,SE ranged from-4.75 to 2.75 *** were divided into five age groups(30–39,40–49,50–59,60–69,and≥70 years)for further *** multivariate analysis by mixed-effect linear model,SR(t=-3.03,P=0.002),OV20%(t=-2.39,P=0.017),and OV9%(t=-3.16,P=0.001)significantly decreased with the increasing age,whereas logMAR BCVA(t=4.42,P<0.001)and OSI(t=4.46,P<0.001)significantly increased with *** SE increased,SR(t=2.74,P=0.01),OV20%(t=2.31,P=0.02),and OV9%(t=2.79,P=0.005)significantly elevated,and OSI(t=-3.38,P<0.001)significantly *** the increase in cortical opacity score,all optical quality parameters except for SR significantly decreased,including MTFcutoff(t=-2.78,P=0.01),OV100%(t=-2.78,P=0.005),OV20%(t=-2.60,P=0.009),and OV9%(t=-2.05,P=0.04).As posterior sub capsular opacity score increased,MTFcutoff(t=-2.40,P=0.02)and OV100%(t=-2.40,P=0.01)significantly decreased,while OSI(t=7.56,P<0.00

关键词： Cross-sectional study Prospective study Vision Aging Refractive errors Cataract

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