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ON THE MEASURABILITY FOR FUNCTIONAL OF EMPIRICAL PROCESSES
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作者 朱力行 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期457-462,共6页
In this paper, we give some results for checking the measurability of functional of empirical processes, their direct applications concern with the measurability of statis-tics constructed by Projection pursuit techni... In this paper, we give some results for checking the measurability of functional of empirical processes, their direct applications concern with the measurability of statis-tics constructed by Projection pursuit technique, thus the results obtained provide a basis in theory for projection pursuit study. 展开更多
关键词 ON THE measurability FOR FUNCTIONAL OF EMPIRICAL PROCESSES
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A Hierarchy of Compatibility and Comeasurability Levels in Quantum Logics with Unique Conditional Probabilities 被引量:1
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作者 Gerd Niestegge 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第12期974-980,共7页
In the quantum mechanical Hilbert space formalism, the probabilistic interpretation is a later ad-hoc add-on, more or less enforced by the experimental evidence, but not motivated by the mathematical model itself. A m... In the quantum mechanical Hilbert space formalism, the probabilistic interpretation is a later ad-hoc add-on, more or less enforced by the experimental evidence, but not motivated by the mathematical model itself. A model involving a clear probabilistic interpretation from the very beginning is provided by the quantum logics with unique conditional probabilities. It includes the projection lattices in von Neumann algebras and here probability conditionalization becomes identical with the state transition of the Lueders-von Neumann measurement process. This motivates the definition of a hierarchy of five compatibility and comeasurability levels in the abstract setting of the quantum logics with unique conditional probabilities. Their meanings are: the absence of quantum interference or influence, the existence of a joint distribution, simultaneous measurability, and the independence of the final state after two successive measurements from the sequential order of these two measurements. A further level means that two elements of the quantum logic (events) belong to the same Boolean subalgebra. In the general case, the five compatibility and comeasurability levels appear to differ, but they all coincide in the common Hilbert space formalism of quantum mechanics, in von Neumann algebras, and in some other cases. 展开更多
关键词 quantum measurement conditional probability quantum logic operator algebras
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Several applications of the theory of random conjugate spaces to measurability problems 被引量:4
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作者 Tie-xin GUO Department of Mathematics, School of Science, Beijing University of Aeronautics and Astronautics, Beijing 100083, China 《Science China Mathematics》 SCIE 2007年第5期737-747,共11页
The central purpose of this paper is to illustrate that combining the recently developed theory of random conjugate spaces and the deep theory of Banach spaces can, indeed, solve some difficult measurability problems ... The central purpose of this paper is to illustrate that combining the recently developed theory of random conjugate spaces and the deep theory of Banach spaces can, indeed, solve some difficult measurability problems which occur in the recent study of the Lebesgue (or more general, Orlicz)-Bochner function spaces as well as in a slightly different way in the study of the random functional analysis but for which the measurable selection theorems currently available are not applicable. It is important that this paper provides a new method of studying a large class of the measurability problems, namely first converting the measurability problems to the abstract existence problems in the random metric theory and then combining the random metric theory and the relative theory of classical spaces so that the measurability problems can be eventually solved. The new method is based on the deep development of the random metric theory as well as on the subtle combination of the random metric theory with classical space theory. 展开更多
关键词 random normed module random conjugate space measurability problem 46B09 46H25 46A22 46B22 60H25
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Construction and Regularity of Transition Functions on Polish Spaces under Measurability Conditions 被引量:1
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作者 Liu-er Ye Xian-ping Guo 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2013年第1期1-14,共14页
This paper concerns the construction and regularity of a transition (probability) function of a nonhomogeneous continuous-time Maxkov process with given transition rates and a general state space. Motivating from a ... This paper concerns the construction and regularity of a transition (probability) function of a nonhomogeneous continuous-time Maxkov process with given transition rates and a general state space. Motivating from a lot of restriction in applications of a transition function with continuous (in t ≥0) and consewative transition rates q(t, x, A), we consider the case that q(t, x, A) axe only required to satisfy a mild measurability (in t ≥ O) condition, which is a generalization of the continuity condition. Under the measurability condition we construct a transition function with the given transition rates, provide a necessary and sufficient condition for it to be regular, and further obtain some interesting additional results. 展开更多
关键词 Transition rate transition function construction and regularity measurability condition
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Exploring recent breakthroughs in robotic biomechanical and electrophysiological measurement tools
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作者 Hui-Yao Shi Si Tang +3 位作者 Jia-Lin Shi Peng Yu Chan-Min Su Lian-Qing Liu 《Biomedical Engineering Communications》 2026年第1期35-47,共13页
Single-cell biomechanics and electrophysiology measuring tools have transformed biological research over the last few decades,which enabling a comprehensive and nuanced understanding of cellular behavior and function.... Single-cell biomechanics and electrophysiology measuring tools have transformed biological research over the last few decades,which enabling a comprehensive and nuanced understanding of cellular behavior and function.Despite their high-quality information content,these single-cell measuring techniques suffer from laborious manual processing by highly skilled workers and extremely low throughput(tens of cells per day).Recently,numerous researchers have automated the measurement of cell mechanical and electrical signals through robotic localization and control processes.While these efforts have demonstrated promising progress,critical challenges persist,including human dependency,learning complexity,in-situ measurement,and multidimensional signal acquisition.To identify key limitations and highlight emerging opportunities for innovation,in this review,we comprehensively summarize the key steps of robotic technologies in single-cell biomechanics and electrophysiology.We also discussed the prospects and challenges of robotics and automation in biological research.By bridging gaps between engineering,biology,and data science,this work aims to stimulate interdisciplinary research and accelerate the translation of robotic single-cell technologies into practical applications in the life sciences and medical fields. 展开更多
关键词 BIOMECHANICS ELECTROPHYSIOLOGY micro-nano manipulation automated cell measurement ROBOTICS
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Magnetic Properties and Kondo Effect in Ce_(3)TiBi_(5) under High Pressure
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作者 L.C.Fu W.J.Cheng +11 位作者 L.C.Shi B.S.Min Y.Peng J.Zhang J.Song Z.Deng J.F.Zhao Y.Liu J.L.Zhu J.F.Zhang X.C.Wang C.Q.Jin 《Chinese Physics Letters》 2026年第1期184-197,共14页
The magnetic properties and Kondo effect in Ce3TiBi5 with a quasi-one-dimensional structure were investigated using in situ high-pressure resistivity measurements up to 48 GPa.At ambient pressure,Ce_(3)TiBi_(5) underg... The magnetic properties and Kondo effect in Ce3TiBi5 with a quasi-one-dimensional structure were investigated using in situ high-pressure resistivity measurements up to 48 GPa.At ambient pressure,Ce_(3)TiBi_(5) undergoes an antiferromagnetic(AFM)transition at T_(N)∼5 K.Under high pressures within 8.9 GPa,we find that Kondo scattering contributes differently to the high-temperature resistance,R(T),depending on the applied current direction,demonstrating a significantly anisotropic Kondo effect.The complete P–T phase diagram has been constructed,in which the pressure dependence of T_(N) exhibits a dome-like shape.The AFM order remains robust under pressure,even when the coherence temperature T^(*) far exceeds 300 K.We attribute the observed anisotropic Kondo effect and the robust AFM to the underlying anisotropy in electronic hybridization under high pressure. 展开更多
关键词 magnetic properties resistivity measurements high pressure kondo effect kondo effectthe kondo scattering Ce TbI
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MEMS gyroscope technology in defence systems:An application-oriented perspective with new analytical results
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作者 Behzad Ahi 《Defence Technology(防务技术)》 2026年第1期389-406,共18页
Microelectromechanical systems(MEMS)technology has gained significant attention over the past decade for measuring inertial angular velocity.However,due to inherent complexity,MEMS gyroscopes typically feature up to t... Microelectromechanical systems(MEMS)technology has gained significant attention over the past decade for measuring inertial angular velocity.However,due to inherent complexity,MEMS gyroscopes typically feature up to ten times more parameters than traditional sensors,making selection a challenging task even for experts.This study addresses this challenge,focusing on defensive guidance,navigation,and control(GNC)systems where precise and reliable angular velocity measurement is critical to overall performance.A comprehensive mathematical model is introduced to encapsulate all key MEMS parameters,accompanied by discussions on calibration and Allan variance interpretation.For six leading MEMS gyroscope applications,namely inertial navigation,integrated navigation,autopilot systems,rotating projectiles,homing guidance,and north finding,the most critical parameters are identified,distinguishing suitable and unsuitable sensor choices.Special emphasis is placed on inertial navigation systems,where practical rules of thumb for error evaluation are derived using six degrees of freedom motion equations.Rigorous simulations demonstrate the influence of various sensor parameters through real-world case studies,including static navigation,multi-rotor attitude estimation,gimbal stabilization,and north finding via a turntable.This work aims to be a beacon for practitioners across diverse fields,empowering them to make more informed design decisions. 展开更多
关键词 Micro-electromechanical system Inertial measurement unit Calibration Sensor fusion GUIDANCE Precision navigation Active disturbance rejection control Attitude and heading reference system
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Integrated N_(2)-Ar measurements of trace extraterrestrial samples
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作者 Fei Su XuHang Zhang +5 位作者 ChuanTong Zhang YouJuan Li ZiHeng Liu JianNan Li HeJiu Hui HuaiYu He 《Earth and Planetary Physics》 2026年第1期22-29,共8页
As one of the major volatile components in extraterrestrial materials,nitrogen(N_(2))isotopes serve not only as tracers for the formation and evolution of the solar system,but also play a critical role in assessing pl... As one of the major volatile components in extraterrestrial materials,nitrogen(N_(2))isotopes serve not only as tracers for the formation and evolution of the solar system,but also play a critical role in assessing planetary habitability and the search for extraterrestrial life.The integrated measurement of N_(2)and argon(Ar)isotopes by using noble gas mass spectrometry represents a state-of-the-art technique for such investigations.To support the growing demands of planetary science research in China,we have developed a high-efficiency,high-precision method for the integrated analysis of N_(2)and Ar isotopes.This was achieved by enhancing gas extraction and purification systems and integrating them with a static noble gas mass spectrometer.This method enables integrated N_(2)-Ar isotope measurements on submilligram samples,significantly improving sample utilization and reducing the impact of sample heterogeneity on volatile analysis.The system integrates CO_(2)laser heating,a modular two-stage Zr-Al getter pump,and a CuO furnace-based purification process,effectively reducing background levels(N_(2)blank as low as 0.35×10^(−6)cubic centimeters at standard temperature and pressure[ccSTP]).Analytical precision is ensured through calibration with atmospheric air and CO corrections.To validate the reliability of the method,we performed N_(2)-Ar isotope analyses on the Allende carbonaceous chondrite,one of the most extensively studied meteorites internationally.The measured N_(2)concentrations range from 19.2 to 29.8 ppm,withδ15N values between−44.8‰and−33.0‰.Concentrations of 40Ar,36Ar,and 38Ar are(12.5-21.1)×10^(−6)ccSTP/g,(90.9-150.3)×10^(−9)ccSTP/g,and(19.2-30.7)×10^(−9)ccSTP/g,respectively.These values correspond to cosmic-ray exposure ages of 4.5-5.7 Ma,consistent with previous reports.Step-heating experiments further reveal distinct release patterns of N and Ar isotopes,as well as their associations with specific mineral phases in the meteorite.In summary,the combined N_(2)-Ar isotopic system offers significant advantages for tracing volatile sources in extraterrestrial materials and will provide essential analytical support for upcoming Chinese planetary missions,such as Tianwen-2. 展开更多
关键词 integrated N_(2)-Ar measurement noble gas mass spectrometer extraterrestrial samples
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APOEε4 Allele Modifies the Association of Heavy Metals and their Mixture with Diabetes Mellitus among Chinese Community-Dwelling Older Adults
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作者 Lili Yao Ying Cao +10 位作者 Beibei Yin Qiang Liu Fusheng Lin Xuqiu Cheng Ziwei Tian Linsheng Yang Hongjuan Cao Liang Sun Fangbiao Tao Li Wang Guimei Chen 《Biomedical and Environmental Sciences》 2026年第1期123-128,共6页
In 2021,approximately 537 million people suffered from diabetes mellitus(DM)globally,and this figure will increase to approximately 783 million within the next quarter-century.The increasing burden of DM is a pressing... In 2021,approximately 537 million people suffered from diabetes mellitus(DM)globally,and this figure will increase to approximately 783 million within the next quarter-century.The increasing burden of DM is a pressing global public health issue.Therefore,the early identification of high-risk groups and implementation of effective intervention measures is imperative. 展开更多
关键词 effective intervention measures heavy metals Chinese community dwelling older adults global public health issue diabetes mellitus dm globallyand APOE allele diabetes mellitus early identification
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σ HYPERFIELD AND THE MEASURABILITY OF MULTIVALUED MAPPINGS
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作者 汪培庄 《Chinese Science Bulletin》 SCIE EI CAS 1983年第12期1583-1585,共3页
Study on the multivalued mappings is very important for fuzzy sets theory. I. R.Goodman, H. T. Nguyen, E. Sanchez and the present author, from the point of view on the multivalued mapping, have treated the fuzzy subse... Study on the multivalued mappings is very important for fuzzy sets theory. I. R.Goodman, H. T. Nguyen, E. Sanchez and the present author, from the point of view on the multivalued mapping, have treated the fuzzy subsets as random sets. 展开更多
关键词 Goodman measurable ordinary struc 丽南 PERL INVERSE 忍人
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Phase distortion correction of fringe patterns in spaceborne Doppler asymmetric spatial heterodyne interferometry 被引量:1
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作者 PEI Hui-yi JIANG Lun +4 位作者 WANG Jin-jiang CUI Yong FANG Yuan-xiang ZHANG Jia-ming CHEN Ci 《中国光学(中英文)》 北大核心 2025年第2期382-392,共11页
As an advanced device for observing atmospheric winds,the spaceborne Doppler Asymmetric Spatial Heterodyne(DASH)interferometer also encounters challenges associated with phase distortion,par-ticularly in limb sounding... As an advanced device for observing atmospheric winds,the spaceborne Doppler Asymmetric Spatial Heterodyne(DASH)interferometer also encounters challenges associated with phase distortion,par-ticularly in limb sounding scenarios.This paper discusses interferogram modeling and phase distortion cor-rection techniques for spaceborne DASH interferometers.The modeling of phase distortion interferograms with and without Doppler shift for limb observation was conducted,and the effectiveness of the analytical expression was verified through numerical simulation.The simulation results indicate that errors propagate layer by layer while using the onion-peeling inversion algorithm to handle phase-distorted interferograms.In contrast,the phase distortion correction algorithm can achieve effective correction.This phase correction method can be successfully applied to correct phase distortions in the interferograms of the spaceborne DASH interferometer,providing a feasible solution to enhance its measurement accuracy. 展开更多
关键词 Doppler asymmetric spatial heterodyne spectroscopy phase distortion phase inversion atmospheric wind measurement
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Voices that matter:The impact of patient-reported outcome measures on clinical decision-making 被引量:1
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作者 Naveen Jeyaraman Madhan Jeyaraman +2 位作者 Swaminathan Ramasubramanian Sangeetha Balaji Sathish Muthu 《World Journal of Methodology》 2025年第2期54-61,共8页
The critical role of patient-reported outcome measures(PROMs)in enhancing clinical decision-making and promoting patient-centered care has gained a profound significance in scientific research.PROMs encapsulate a pati... The critical role of patient-reported outcome measures(PROMs)in enhancing clinical decision-making and promoting patient-centered care has gained a profound significance in scientific research.PROMs encapsulate a patient's health status directly from their perspective,encompassing various domains such as symptom severity,functional status,and overall quality of life.By integrating PROMs into routine clinical practice and research,healthcare providers can achieve a more nuanced understanding of patient experiences and tailor treatments accordingly.The deployment of PROMs supports dynamic patient-provider interactions,fostering better patient engagement and adherence to tre-atment plans.Moreover,PROMs are pivotal in clinical settings for monitoring disease progression and treatment efficacy,particularly in chronic and mental health conditions.However,challenges in implementing PROMs include data collection and management,integration into existing health systems,and acceptance by patients and providers.Overcoming these barriers necessitates technological advancements,policy development,and continuous education to enhance the acceptability and effectiveness of PROMs.The paper concludes with recommendations for future research and policy-making aimed at optimizing the use and impact of PROMs across healthcare settings. 展开更多
关键词 Patient-reported outcome measures Clinical decision-making Patient-centered care Healthcare technology Data management Policy development
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Variations in quantifying patient reported outcome measures to estimate treatment effect 被引量:1
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作者 Sathish Muthu Srujun Vadranapu 《World Journal of Methodology》 2025年第2期44-53,共10页
In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence ... In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice. 展开更多
关键词 Patient-reported outcome measures Treatment effect Minimal clinical important difference Patient-accepted symptom state Minimum detectable change ORTHOPEDICS
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Coal-rock gas accumulation mechanism and the whole petroleum system of coal measures 被引量:1
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作者 LI Guoxin JIA Chengzao +2 位作者 ZHAO Qun ZHOU Tianqi GAO Jinliang 《Petroleum Exploration and Development》 2025年第1期33-49,共17页
Coal measures are significant hydrocarbon source rocks and reservoirs in petroliferous basins.Many large gas fields and coalbed methane fields globally are originated from coal-measure source rocks or accumulated in c... Coal measures are significant hydrocarbon source rocks and reservoirs in petroliferous basins.Many large gas fields and coalbed methane fields globally are originated from coal-measure source rocks or accumulated in coal rocks.Inspired by the discovery of shale oil and gas,and guided by“the overall exploration concept of considering coal rock as reservoir”,breakthroughs in the exploration and development of coal-rock gas have been achieved in deep coal seams with favorable preservation conditions,thereby opening up a new development frontier for the unconventional gas in coal-rock reservoirs.Based on the data from exploration and development practices,a systematic study on the accumulation mechanism of coal-rock gas has been conducted.The mechanisms of“three fields”controlling coal-rock gas accumulation are revealed.It is confirmed that the coal-rock gas is different from CBM in accumulation process.The whole petroleum systems in the Carboniferous–Permian transitional facies coal measures of the eastern margin of the Ordos Basin and in the Jurassic continental facies coal measures of the Junggar Basin are characterized,and the key research directions for further developing the whole petroleum system theory of coal measures are proposed.Coal rocks,compared to shale,possess intense hydrocarbon generation potential,strong adsorption capacity,dual-medium reservoir properties,and partial or weak oil and gas self-sealing capacity.Additionally,unlike other unconventional gas such as shale gas and tight gas,coal-rock gas exhibits more complex accumulation characteristics,and its accumulation requires a certain coal-rock play form lithological and structural traps.Coal-rock gas also has the characteristics of conventional fractured gas reservoirs.Compared with the basic theory and model of the whole petroleum system established based on detrital rock formations,coal measures have distinct characteristics and differences in coal-rock reservoirs and source-reservoir coupling.The whole petroleum system of coal measures is composed of various types of coal-measure hydrocarbon plays with coal(and dark shale)in coal measures as source rock and reservoir,and with adjacent tight layers as reservoirs or cap or transport layers.Under the action of source-reservoir coupling,coal-rock gas is accumulated in coal-rock reservoirs with good preservation conditions,tight oil/gas is accumulated in tight layers,conventional oil/gas is accumulated in traps far away from sources,and coalbed methane is accumulated in coal-rock reservoirs damaged by later geological processes.The proposed whole petroleum system of coal measures represents a novel type of whole petroleum system. 展开更多
关键词 coal measure coal-rock gas coalbed methane tight gas coal-rock play accumulation mechanism whole petroleum system whole petroleum system of coal measures
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Radiation investigation behind 4.7 km/s shock waves with nitrogen using a square section shock tube 被引量:1
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作者 Senhao Zhang Yuzhe Zhang +6 位作者 Yixin Xu Tianrui Bai Kai Luo Renjie Li Qiu Wang Xin Lin Fei Li 《Acta Mechanica Sinica》 2025年第3期13-22,共10页
The thermochemical non-equilibrium phenomena encountered by hypersonic vehicles present significant challenges in their design.To investigate the thermochemical reaction flow behind shock waves,the non-equilibrium rad... The thermochemical non-equilibrium phenomena encountered by hypersonic vehicles present significant challenges in their design.To investigate the thermochemical reaction flow behind shock waves,the non-equilibrium radiation in the visible range using a shock tube was studied.Experiments were conducted with a shock velocity of 4.7 km/s,using nitrogen at a pressure of 20 Pa.To address measurement difficulties associated with weak radiation,a special square section shock tube with a side length of 380 mm was utilized.A high-speed camera characterized the shock wave’s morphology,and a spectrograph and a monochromator captured the radiation.The spectra were analyzed,and the numerical spectra were compared with experimental results,showing a close match.Temperature changes behind the shock wave were obtained and compared with numerical predictions.The findings indicate that the vibrational temperatures are overestimated,while the vibrational relaxation time is likely underestimated,due to the oversimplified portrayals of the non-equilibrium relaxation process in the models.Additionally,both experimental and simulated time-resolved profiles of radiation intensity at specific wavelengths were analyzed.The gathered data aims to enhance computational fluid dynamics codes and radiation models,improving their predictive accuracy. 展开更多
关键词 Nitrogen radiation NON-EQUILIBRIUM Spectral measurement Shock waves Shock tube
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Field survey of building damage at Mandalay during 2025 Myanmar M_(w)7.7 earthquake 被引量:1
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作者 Wang Tao Zhou Yujiang +3 位作者 Chen Jie Wang Xiaoqing Bi Hongyi Wang Xiaoting 《Earthquake Engineering and Engineering Vibration》 2025年第3期613-627,共15页
On March 28,2025,an M_(w) 7.7 earthquake struck near Mandalay,Myanmar,producing intense ground shaking.Strong motion recorded at a station close to the fault indicated a peak ground acceleration of 1.066 g in the vert... On March 28,2025,an M_(w) 7.7 earthquake struck near Mandalay,Myanmar,producing intense ground shaking.Strong motion recorded at a station close to the fault indicated a peak ground acceleration of 1.066 g in the vertical direction and 0.631 g in the horizontal direction.The earthquake caused collapse or severe damage of numerous buildings,resulting in thousands of fatalities and injuries,as well as substantial economic losses.The authors participated in the post-earthquake emergency response as members of the China Search and Rescue Team.During the rescue operations,an investigation into the characteristics of collapsed structures was conducted and the stability of building debris was assessed to ensure the safety of rescue efforts.Subsequently,a rapid seismic safety assessment of affected structures was carried out,including nine city residential blocks,two hospitals,and two apartments.Preliminary analyses indicate that the main causes of structural failure were insufficient cross-sectional dimensions of beams and columns,inadequate stirrup reinforcement,and lack of structural redundancy. 展开更多
关键词 Myanmar earthquake collapsed buildings seismic measures site conditions design code
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Civil aviation emissions in China in 2019:Characteristics and abatement potential 被引量:1
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作者 Haowen An Yu Wang +3 位作者 Yaxin Wang Jun Liu Xiaolong Tang Honghong Yi 《Journal of Environmental Sciences》 2025年第5期225-237,共13页
Civil aviation is one of the industries facing the greatest challenge in reaching carbon neutrality by the middle of this century,and this sector also contributes to adverse impacts on the regional air quality and hum... Civil aviation is one of the industries facing the greatest challenge in reaching carbon neutrality by the middle of this century,and this sector also contributes to adverse impacts on the regional air quality and human health.China exhibits the second highest air passenger turnover worldwide.Our understanding of civil aviation emissionsmust be urgently enhanced,and themitigation potential should be explored.In this study,on the basis of real domestic flight information for 2019,we built a greenhouse gas and air pollution emission inventory for the civil aviation sector in China with the fuel flowmethod based on the cruise and other phases.We thoroughly analyzed emissions by region,aircraft and engine types,and aircraft age,based on which we designed four measures to evaluate the abatement potential.We found that the hydrocarbon(HC),CO,NO_(x),SO_(2),particulate matter(PM)and CO_(2)emissions in 2019 reached 79.9 kt(95%CI[51.6–114.5]),176.3 kt(95%CI[114.5–248.2]),304.2 kt(95%CI[203.4–420.7]),23.2 kt(95%CI[14.2–33.7]),1.0 kt(95%CI[0.61–1.44])and 87.0 Mt(95%CI[57.4–119.6]),respectively.The cruise phase was the major emission phase,accounting for 67%-87%of the total pollutant emissions.If four measures were jointly implemented,the HC,CO,NO_(x),SO_(2),PM and CO_(2)emissions could be reduced by 61%,54%,55%,45%,32%and 38%,respectively.Utilizing lower-emission aircraft and switching travel modes could substantially reduce civil aviation emissions in China. 展开更多
关键词 Emission inventory Fuel flow method Cruise emission Age structure Reduction measures
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Digital twin-based resilience evaluation and intelligent strategies of smart urban water distribution networks for emergency management 被引量:1
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作者 Hongyan Dui Taiyu Cao Fan Wang 《Resilient Cities and Structures》 2025年第1期41-52,共12页
Resilient smart urban water distribution networks are essential to ensure smooth urban operation and maintain daily water services.However,the dynamics and complexity of smart water distribution networks make its re-s... Resilient smart urban water distribution networks are essential to ensure smooth urban operation and maintain daily water services.However,the dynamics and complexity of smart water distribution networks make its re-silience study face many challenges.The introduction of digital twin technology provides an innovative solution for the resilience study of smart water distribution networks,which can more effectively support the network’s real-time monitoring and intelligent control.This paper proposes a digital twin architecture of smart water dis-tribution networks,laying the foundation for the resilience assessment of water distribution networks.Based on this,a performance evaluation model based on user satisfaction is proposed,which can more intuitively and effectively reflect the performance of urban water supply services.Meanwhile,we propose a method to quantify the importance of water distribution pipes’residual resilience,considering the time value to optimize the re-covery sequence of failed pipes and develop targeted preventive maintenance strategies.Finally,to validate the effectiveness of the proposed method,this paper applies it to a water distribution network.The results show that the proposed method can significantly improve the resilience and enhance the overall resilience of smart urban water distribution networks. 展开更多
关键词 Digital twin Smart water distribution network Resilience evaluation Importance measure
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MODIFIED BRASCAMP-LIEB INEQUALITIES AND LOG-SOBOLEV INEQUALITIES FOR ONE-DIMENSIONAL LOG-CONCAVE MEASURE 被引量:1
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作者 Denghui WU Jiazu ZHOU 《Acta Mathematica Scientia》 2025年第1期104-117,共14页
In this paper,we develop Maurey’s and Bobkov-Ledoux’s methods to prove modified Brascamp-Lieb inequalities and log-Sobolev inequalities for one-dimensional log-concave measure.To prove these inequalities,the harmoni... In this paper,we develop Maurey’s and Bobkov-Ledoux’s methods to prove modified Brascamp-Lieb inequalities and log-Sobolev inequalities for one-dimensional log-concave measure.To prove these inequalities,the harmonic Prékopa-Leindler inequality is used.We prove that these new inequalities are more efficient in estimating the variance and entropy for some functions with exponential terms. 展开更多
关键词 Brunn-Minkowski inequality Prékopa-Leindler inequality Brascamp-Lieb inequality log-Sobolev inequality log-concave measure
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Application of Fuzzy Inference System in Gas Turbine Engine Fault Diagnosis Against Measurement Uncertainties 被引量:1
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作者 Shuai Ma Yafeng Wu +1 位作者 Zheng Hua Linfeng Gou 《Chinese Journal of Mechanical Engineering》 2025年第1期62-83,共22页
Robustness against measurement uncertainties is crucial for gas turbine engine diagnosis.While current research focuses mainly on measurement noise,measurement bias remains challenging.This study proposes a novel perf... Robustness against measurement uncertainties is crucial for gas turbine engine diagnosis.While current research focuses mainly on measurement noise,measurement bias remains challenging.This study proposes a novel performance-based fault detection and identification(FDI)strategy for twin-shaft turbofan gas turbine engines and addresses these uncertainties through a first-order Takagi-Sugeno-Kang fuzzy inference system.To handle ambient condition changes,we use parameter correction to preprocess the raw measurement data,which reduces the FDI’s system complexity.Additionally,the power-level angle is set as a scheduling parameter to reduce the number of rules in the TSK-based FDI system.The data for designing,training,and testing the proposed FDI strategy are generated using a component-level turbofan engine model.The antecedent and consequent parameters of the TSK-based FDI system are optimized using the particle swarm optimization algorithm and ridge regression.A robust structure combining a specialized fuzzy inference system with the TSK-based FDI system is proposed to handle measurement biases.The performance of the first-order TSK-based FDI system and robust FDI structure are evaluated through comprehensive simulation studies.Comparative studies confirm the superior accuracy of the first-order TSK-based FDI system in fault detection,isolation,and identification.The robust structure demonstrates a 2%-8%improvement in the success rate index under relatively large measurement bias conditions,thereby indicating excellent robustness.Accuracy against significant bias values and computation time are also evaluated,suggesting that the proposed robust structure has desirable online performance.This study proposes a novel FDI strategy that effectively addresses measurement uncertainties. 展开更多
关键词 Performance-based fault diagnosis Gas turbine engine Fuzzy inference system Measurement uncertainty Regression and classification
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