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SEDIMENT TRANSPORT CAPACITY-AN IMPROVED BAGNOLD FORMULA

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International Journal of Sediment Research 2007年第1期22卷 27-38页

作者： Sung-Cheol KOH In-Soo KIM young-chae song

This paper re-examines Bagnold’s theorem of sediment transport. Different from the stream power defined by Bagnold, i.e., τoV, this study shows that the total load of sediment-laden flow, gt, is related to near bed energy dissipation rate, i.e., τou*’. An attempt is made to explain the empirical relation. The ratio (=k) of measured total load, gt, to the product of near bed velocity, u*’, and energy dissipation rate, τou*’, is analyzed. It is found that k is independent of the Rouse number, Z, if Z is greater than 2.6, but the coefficient k decreases with the increase of Z when Z < 2.6. An empirical relation between k and Z is developed. A systematic and thorough analysis of 1,458 sets of data collected from 16 rivers and canals confirms that the proposed formula can be used to compute the total load with accuracy.

关键词： Sediment transport River flow Total sediment discharge Stream power

Increased risk of colorectal cancer in young males with higher cardiovascular risk:A nationwide population-based cohort study

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 69-80页

作者： Ji Hyun song Su-Yeon Choi young Sun Kim Sun young Yang Kyung-Do Han Internal Medicine and Healthcare Research Institute Seoul National University Hospital Healthcare System Gangnam CenterSeoul 06236South Korea Internal Medicine Seoul National University HospitalSeoul National University College of MedicineSeoul 06236South Korea Department of Statistics and Actuarial Science Soongsil UniversitySeoul 06978South Korea

BACKGROUND Although the link between cardiovascular disease(CVD)and various cancers is well-established,the relationship between CVD risk and colorectal cancer(CRC)remains *** To elucidate the relationship between CVD risk scores and CRC *** In this population-based cohort study,participants from the 2009 National Health Checkup were followed-up until *** cardiovascular(CV)risk score was calculated as the sum of risk factors(age,family history of coronary artery disease,hypertension,smoking status,and high-density lipoprotein levels)with high-density lipoprotein(≥60 mg/dL)reducing the risk score by *** primary outcome was incidence of newly diagnosed *** Among 2526628 individuals,30329 developed CRC during a mean follow-up of 10.1 *** by CV risk scores(0,1,2,and≥3).CRC risk increased with higher CV risk scores after adjusting for covariates[(hazard ratio=1.155,95%confidence interval:1.107-1.205)in risk score≥3,Pyounger populations,and non-statin ***,males with a higher CV risk score,even at a younger age,are recommended to control their risk factors and undergo individualized CRC screening.

关键词： Colorectal cancer Cardiovascular disease Cohort study Age Gender

Establishing the vector-meson-exchange dominance for the short range interactions of light quarks

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Science China(Physics,Mechanics & Astronomy) 2025年第3期68卷 190-191页

作者： Bing-song Zou Department of Physics Tsinghua UniversityBeijing100084China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing100190China School of Physics University of Chinese Academy of SciencesBeijing100049China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou516000China

Understanding the interactions between constituent quarks is one of the fundamental and challenging problems in hadron *** present,the constituent quark models have achieved great success in describing the properties of hadrons,whereas some long-standing disputes remain,especially for the short range interactions between constituent *** exploring the dynamic mechanism between u/d quarks,it is found that the one gluon exchange and/or vector meson exchange induced interactions may dominate the short range interactions[1].

关键词： quark exchange meson

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Bilinear magnetoelectric resistance induced by spin Hall effect

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Science China Materials 2025年第2期68卷 687-688页

作者： Ruiyue Chu Cheng song School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Magnetoresistance(MR)is a fundamental transport phenomenon crucial for reading magnetic *** also plays a key role in understanding how time-reversal symmetry breaking affects electrical *** discoveries of anisotropic MR[1],giant MR[2],tunneling MR[3],and spin Hall magnetoresistance[4]have driven the development of diverse spintronic devices used in data storage,computing,and sensing ***,these MR effects do not scale linearly with the electric field(and thus,electric current).Recently,nonlinear MR,which scales specifically with the electric current(Ic),has been *** magnetic/non-magnetic bilayers,unidirectional spin Hall magnetoresistance(USMR)[5]shows a linear dependence on Ic,with voltage scaling quadratically with the applied electric field,due to interfacial spin-dependent and electron-magnon scattering mechanisms.

关键词： breaking symmetry linearly

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science China Earth Sciences 2025年第1期68卷 270-296页

作者： song XIANG Jinshui HUANG Bingcheng WU School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China CAS Center of Excellence in Comparative Planetary Studies Hefei230026China

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell *** five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,*** typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and *** results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five ***,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes ***,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic ***,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate *** fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental *** the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective *** tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal *** the lithospheric strength was only 150 MPa,plate tecton

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

Disordered hyperuniformity and thermal transport in monolayer amorphous carbon

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 145-152页

作者： Nianjie Liang Yuxi Wang Bai song Department of Energy and Resources Engineering Peking UniversityBeijing 100871China Department of Advanced Manufacturing and Robotics Peking UniversityBeijing 100871China

Disordered hyperuniformity(DHU)is a recently discovered novel state of amorphous systems characterized by strongly suppressed density fluctuations at large length scales as in crystalline materials,which offers great potential for achieving unusual mechanical,electronic,and photonic ***,despite the fundamental and technological importance of thermal transport in amorphous solids,the effect of DHU remains largely ***,we theoretically study thermal transport in a class of two-dimensional DHU materials—monolayer amorphous carbon(MAC).Beginning with a perfect graphene lattice,we continuously apply Stone-Wales transformations to generate a series of MAC models with varied degrees of disorder and defects,which are quantified through comprehensive structural analysis including the so-called hyperuniformity index(H),where a smaller H indicates a higher degree of ***,we conduct molecular dynamics simulations to obtain the thermal conductivity(κ).A significant correlation between the thermal transport behavior and degree of hyperuniformity is observed,with the room-temperatureκdecreasing from 26.3 to 5.3 W m^(-1)K^(-1)while H is tuned from 0.0004 to ***,two distinct transport regimes are identified,including a nearly-DHU regime at small H(<0.005)whereκdrops sharply and a non-DHU region at larger H whereκbecomes relatively ***-resolved analysis reveals longer lifetime and higher participation ratio for the heat carriers in nearly-DHU MAC,implying that the hidden long-range correlations could support extended modes that enhance *** work highlights the impact of DHU on the thermal properties of amorphous materials and represents a conceptual advancement that is worthy of future exploration.

关键词： disordered hyperuniformity thermal transport amorphous material two-dimensional monolayer amorphous carbon

Unifying Fixed Time and Prescribed Time Control for Strict-Feedback Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 347-355页

作者： Xiang Chen Yujuan Wang Yongduan song the State Key Laboratory of Power Transmission Equipment & System Security and New Technology and School of Automation Chongqing University IEEE

This paper investigates the prescribed-time tracking control problem for a class of multi-input multi-output(MIMO)nonlinear strict-feedback systems subject to non-vanishing uncertainties. The inherent unmatched and non-vanishing uncertainties make the prescribed-time control problem become much more nontrivial. The solution to address the challenges mentioned above involves incorporating a prescribed-time filter, as opposed to a finite-time filter, and formulating a prescribed-time Lyapunov stability lemma(Lemma 5). The prescribed-time Lyapunov stability lemma is based on time axis shifting time-varying yet bounded gain, which establishes a novel link between the fixed-time and prescribed-time control method. This allows the restriction condition that the time-varying gain function must satisfy as imposed in most exist prescribed-time control works to be removed. Under the proposed control method, the desire trajectory is ensured to closely track the output of the system in prescribed time. The effectiveness of the theoretical results are verified through numerical simulation.

关键词： Prescribed-time control prescribed-time filter robust control state feedback strict-feedback systems

Advancements in implantable temperature sensors:Materials,mechanisms,and biological applications

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Journal of Semiconductors 2025年第1期46卷 166-177页

作者： Zhuofan Yang Hongcheng song He Ding Beijing Engineering Research Center of Mixed Reality and Advanced Display School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China Department of Urology Beijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijing 100045China

Implantable temperature sensors are revolutionizing physiological monitoring and playing a crucial role in diagnostics,therapeutics,and life sciences *** review classifies the materials used in these sensors into three categories:metal-based,inorganic semiconductor,and organic semiconductor ***-based materials are widely used in medical and industrial applications due to their linearity,stability,and *** semiconductors provide rapid response times and high miniaturization potential,making them promising for biomedical and environmental *** semiconductors offer high sensitivity and ease of processing,enabling the development of flexible and stretchable *** review analyzes recent studies for each material type,covering design principles,performance characteristics,and applications,highlighting key advantages and challenges regarding miniaturization,sensitivity,response time,and ***,critical performance parameters of implantable temperature sensors based on different material types are summarized,providing valuable references for future sensor design and *** future development of implantable temperature sensors is discussed,focusing on improving biocompatibility,long-term stability,and multifunctional *** advancements are expected to expand the application potential of implantable sensors in telemedicine and dynamic physiological monitoring.

关键词： implantable temperature sensors biological applications flexible electronics

Seismic isolation design and resilience improvement of railway station considering the influence of near-fault pulse-like ground motions

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 257-270页

作者： Pan Yi song Jiayu Chen Qi Liu Yongxin School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Seismic Engineering of Sichuan Province Chengdu 610031China

To improve the resilience of railway stations,a typical station was selected as the research object,and an isolation design was ***-four groups of near-fault pulse-like ground motions were *** seismic resilience of the no-isolation railway stations(NIRS)and the isolation railway stations(IRS)were compared to provide a numerical result of the improvement in *** results show that in the station isolation design,the station's functional requirements and structural characteristics should be considered and the appropriate placement of isolation bearings is under the waiting *** the action of a rare earthquake,the repair cost,repair time,rate of harm and death of the IRS were decreased by 8.04 million,18.30 days,6.93×10^(-3)and 1.21×10^(-3),respectively,when compared to the *** IRS received a seismic resilience grade of three-stars and the NIRS only one-star,indicating that rational isolation design improves the seismic resilience of ***,for the design of stations close to earthquake faults,it is suggested to utilize appropriate isolation techniques to improve their seismic resilience.

关键词： railway station near-fault pulse-like ground motion isolation design seismic resilience resilience improvement