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Microtremor-based analysis of the dynamic response characteristics of earth-fissured sites in the Datong basin, China

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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 567-582页

作者： xuan you Deng Yahong He Jia Chang Jiang Yan Zuofei Wu Wei Department of Geological Engineering Chang′an UniversityXi′an 710064China Key Laboratory of Mine Geological Hazards Mechanism and Control Xi’an 710064China

This study conducted microtremor testing along six survey lines that cross three typical earth fissures in the Datong basin to determine the dynamic response characteristics of earth fissure sites with regard to the Fourier amplitude spectrum,response spectrum,and Arias *** results show the following.(1)The predominant frequency of an earth fissure site is mainly affected by the thickness and the shear wave velocity of the soil layer and is minimally effected by the presence of an earth fissure.(2)Earth fissures have a pronounced amplification effect on dynamic *** amplitude,response acceleration,and Arias intensity are high near an earth fissure and decrease with an increase in distance from the earth fissure,tending toward stability at a distance of 20 m.(3)The area that is seriously affected by this amplification is within 6-8 m of an earth fissure,and the general affected area is farther out than this,to a distance of 25 m.(4)New construction should be avoided in an area affected by the amplification,and existing buildings in general and seriously affected areas need to be reinforced to increase their seismic fortification intensity.

关键词： earth fissures microtremor testing predominant frequency amplification effect affected area mitigation measures

A Region Enhanced Discrete Multi-Objective Fireworks Algorithm for Low-Carbon Vehicle Routing Problem

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Complex System Modeling and Simulation 2022年第2期2卷 142-155页

作者： Xiaoning Shen Jiaqi Lu xuan you Liyan Song Zhongpei Ge Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Big Data Analysis TechnologySchool of AutomationNanjing University of Information Science and TechnologyNanjing 210044China School of Automation Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Trustworthy Autonomous Systems and also with the Guangdong Provincial Key Laboratory of Brain-Inspired Intelligent ComputationDepartment of Computer Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China

A constrained multi-objective optimization model for the low-carbon vehicle routing problem(VRP)is established.A carbon emission measurement method considering various practical factors is *** minimizes both the total carbon emissions and the longest time consumed by the sub-tours,subject to the limited number of available *** to the characteristics of the model,a region enhanced discrete multi-objective fireworks algorithm is proposed.A partial mapping explosion operator,a hybrid mutation for adjusting the sub-tours,and an objective-driven extending search are designed,which aim to improve the convergence,diversity,and spread of the non-dominated solutions produced by the algorithm,*** low-carbon VRP instances with different scales are used to verify the effectiveness of the new ***,comparison results with four state-of-the-art algorithms indicate that the proposed algorithm has better performance of convergence and distribution on the low-carbon *** provides a promising scalability to the problem size.

关键词： vehicle routing problem carbon emission multi-objective optimization fireworks algorithm region enhanced

Microtremor-based analysis of the dynamic response characteristics of a site containing grouped earth fissures

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 689-702页

作者： Deng Yahong xuan you Mu Huandong Chang Jiang Cao Ge He Nainan Zhao Xunchang Sun Longfei College of Geological Engineering and Geomatics Chang′an UniversityXi′an 710064China Key Laboratory of Mine Geological Hazards Mechanism and Control Xi′an 710064China Institute of Geotechnical Engineering Xi′an University of TechnologyXi′an 710048China

In this study,the Beibu earth fissure site in the northeastern part of Weihe Basin,which contains four nearly parallel earth fissures,was studied.A long straight microtremor measuring line,containing 49 measuring points across four earth fissures,was established to investigate the dynamic response of this site using Fourier spectrum,response acceleration spectrum,Arias intensity,and HVSR *** main results are as follows:(1)The fundamental frequencies of 44 measuring points obtained from HVSR analysis are concentrated within 1.67 Hz-2.25 Hz,and the existence of the earth fissures has little effect on the fundamental frequency changes.(2)There is an amplification effect near a single earth *** dynamic responses are large at the measuring points near the earth fissure,and the values decrease with increasing distance from the earth *** areas between two adjacent earth fissures,these values decrease and are even lower than those in sites without amplification effects.(3)In this earth fissure site,the general area(or less affected area)and affected areas were delineated based on the amplification *** engineering applications,construction design should avoid these affected areas and existing structures should be reinforced to satisfy the seismic fortification requirements.

关键词： earth fissure sites microtremors Fourier amplitude spectrum response spectrum arias intensity H/V spectral ratio fundamental frequency amplification effect

Efficient circularly polarized photoluminescence and electroluminescence of chiral spiro-skeleton-based thermally activated delayed fluorescence molecules

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Science China Chemistry 2022年第7期65卷 1347-1355页

作者： Yi-Pin Zhang Shi-Quan Song Meng-Xi Mao Cheng-Hui Li you-xuan Zheng Jing-Lin Zuo State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China MaAnShan High-Tech Research Institute of Nanjing University Maanshan 238200China

Chiral thermally activated delayed fluorescence(TADF) molecules showing circularly polarized luminescence(CPL) have great potential in 3D displays. However, the relationships among CPL property, device performance and molecule structure are still not clear. In this article, we develop a strategy to promote dissymmetry factors without sacrifice in device performance and study the impact of molecule structures towards CPL property. Three novel TADF enantiomers are synthesized and studied.(R/S)-SCN with diminutive cyano group as an acceptor shows dissymmetry factor |gPL| ≈ 1.4×10^(-3) and noticeable organic light-emitting diode(OLED) performances with a maximum external quantum efficiency(EQEmax) of 23.0%. For(R/S)-SPHCN, the prolonged electron withdrawing group benzonitrile enhances |gPL| up to 3.6×10^(-3) with decreased device EQEmaxof 15.4%. By further replacing benzonitrile with(trifluoromethyl)pyridine, the enantiomers of(R/S)-SCFPY show similar |gPL| factors of 3.5×10^(-3) and device EQE_(max)up to 23.3%, which represents the highest efficiency among sprio-type TADF materials based OLEDs. Furthermore, the OLEDs also show obvious circularly polarized electroluminescence with gELfactors of-1.4/1.8×10^(-3),-3.6/3.6×10^(-3) and-3.7/3.6×10^(-3), respectively. These results indecate by delicate functional group engineering, high g factor can be achieved while maintaining decent device performances. Besides,(R/S)-SCFPY represents an impressive TADF emitter, which shows promoted g factor and recorded high device EQE_(max)among similar molecules.

关键词： chiral spiro-skeleton thermally activated delayed fluorescence circularly polarized photoluminescence circularly polarized electroluminescence dissymmetry factor

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Friction identification and compensation design for precision positioning

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Advances in Manufacturing 2017年第2期5卷 120-129页

作者： Feng-Tian Li Li Ma Lin-Tao Mi you-xuan Zeng Ning-Bo Jin Ying-Long Gao School of Mechatronic Engineering and Automation Shanghai University Shanghai 200072 People's Republic of China

Precision positioning systems driven by linear motors are vulnerable to force disturbances owing to the reduction of gear transmission. The friction, included in the disturbance, can be modeled and compensated to improve the servo performance. This paper proposes a modified Stribeck friction model （SFM） and an optimization algorithm for consistency with the positioning platform. The compensators based on the friction model and disturbance observer （DOB） are simulated. The simulation results show that as compared with the DOB compensator （the velocity recovers by 5.19%）, the friction model based compensator （the velocity recovers by 10.66%） exhibits a better performance after adding the disturbance. Moreover, compensation comparisons among the Coulomb friction, traditional SFM, and modified SFM are performed. The experimental results show that the following error with modified SFM compensation improves by 67.67% and 51.63% at a speed of 0.005 m/s and 0.05 m/s, compared with the Coulomb friction compensation. This demonstrates that the proposed model, optimization algorithm, and compensator can reduce the following error effectively.

关键词： Precision positioning Friction compensation Identification Modeling

Microcrack localization using a collinear Lamb wave frequency-mixing technique in a thin plate

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Chinese Physics B 2022年第1期31卷 364-373页

作者： Ji-Shuo Wang Cai-Bin Xu you-xuan Zhao Ning Hu Ming-Xi Deng College of Aerospace Engineering Chongqing UniversityChongqing400044China School of Mechanical Engineering Hebei University of TechnologyTianjin 300401China

A novel Lamb wave frequency-mixing technique is proposed for locating microcracks in a thin plate,which does not require the resonance condition of Lamb wave mixing and can accurately locate the microcracks through only one-time *** on the bilinear stress-strain constitutive model,a two-dimensional finite element(FE)model is built to investigate the frequency-mixing response induced by the interaction between two primary Lamb waves and a *** two primary Lamb waves of A0 and S0 modes with different frequencies excited on the same side of the plate simultaneously impinge on the examined microcrack,under the modulation of the contact acoustic nonlinearity,the microcrack itself can be deemed as the secondary sound source and it will radiate the Lamb waves of new combined *** on the time of flight of the generated A0 mode at difference frequency,an indicator named normalized amplitude index(NAI)is defined to directly locate the multi-microcracks in the given *** is found that the number and location of the microcracks can be intuitively visualized by using the NAI based frequency-mixing *** is also demonstrated that the proposed frequency mixing technique is a promising approach for the microcrack localization.

关键词： frequency-mixing of Lamb waves contact acoustic nonlinearity bilinear stress-strain constitutive model microcrack localization

Chiral multiple-resonance thermally activated delayed fluorescence materials based on chiral spiro-axis skeleton for efficient circularly polarized electroluminescence

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Science China Chemistry 2024年第7期67卷 2257-2264页

作者： Shi-Quan Song Xiao Han Zhong-Zhong Huo Ching-Fai Yip Xian-Fang Hong Meng-Ning Ding you-xuan Zheng State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chiral luminescence materials have potential applications in the field of three-dimensional displays due to their circularly polarized luminescence(CPL)***,the further development of circularly polarized organic light-emitting diodes(CP-OLEDs)needs to meet the requirements of high efficiency,high color purity,low cost,and high dissymmetry factor(gPLor gEL),chiral multiple resonance thermally activated delayed fluorescence(MR-TADF)materials are considered as candidates in these ***,based on a pair of chiral spirofluorene precursors,two pairs of high-performance chiral MR-TADF emitters((R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB)are developed,which exhibit strong emissions peaking at 491 and 502 nm in toluene with full-width at half-maximum values of 25 and 33 nm,*** addition,small singlet–triplet energy gaps of 0.15 and 0.10 eV with high absolute photoluminescence efficiencies of 95.0%and 96.7%are observed for p-Spiro-DtBuCzB and m-Spiro-DtBuCzB molecules,*** based on p-Spiro-DtBuCzB and m-Spiro-DtBuCzB display high maximum external quantum efficiencies of 29.6%and 33.8%,*** importantly,CP-OLEDs present symmetric circularly polarized electroluminescence spectra with|gEL|factors of 3.36×10^(-4)and 7.66×10^(-4)for devices based on(R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB enantiomers,respectively.

关键词： chiral spiro-axis skeleton-based material multiple resonance thermally activated delayed fluorescence circularly polarized electroluminescence dissymmetry factor external quantum efficiency

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Color-tunable circularly polarized electroluminescence from a helical chiral multiple resonance emitter with B–N bonds

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Science China Chemistry 2023年第9期66卷 2612-2620页

作者： Li Yuan Zhen-Long Tu Jun-Wei Xu Hua-Xiu Ni Zhi-Ping Mao Wen-Ye Xu you-xuan Zheng State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Shenzhen Institute of Information Technology Shenzhen 518172China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Guangzhou Research&Creativity Biotechnology Co.Ltd. Guangzhou 510700China

Chiral B,N-doped polycyclic aromatic hydrocarbons with circularly polarized luminescence(CPL) and small full-width at halfmaxima(FWHM) are promising multiple resonance(MR) emitters for CP organic light-emitting diodes(CP-OLEDs).This work presents a pair of chiral MR enantiomers,P/M-o[B-N]_(2)N_(2),featuring B–N bonds incorporated within a[7]-helicene *** enantiomers exhibit narrow 0-0 and 0-1 electronic transition bands,whose relative intensity can be fine-tuned by increasing doping concentrations,resulting in redshifts of the emission peak from 542 to 592 *** enantiomers show mirrorsymmetric CPL spectra with an asymmetry factor(|g_(PL)|) of 1.0×10^(-3).The hyperfluorescent CP-OLEDs with double-sensitized emitting layers display a FWHM of 33 nm,an external quantum efficiency of 25.1%,and a|g_(EL)|factor of 7.7×10^(-4).Notably,the CP-OLEDs realize color-tunable CP electroluminescence peak from 553 to 613 nm by regulating the vibrational *** work provides a novel concept for the design of helical CP-MR materials and CP-OLEDs,highlighting their potential for future applications in advanced optoelectronic devices.

关键词： chiral multiple resonance material helical chirality circularly polarized luminescence narrowband emission color-tunable circularly polarized electroluminescence

Anxiety and depression symptoms among ovarian cancer patients in China:a cross-sectional study

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Frontiers of Nursing 2020年第4期7卷 321-327页

作者： Jing Chen De-Rong Long Xiu-Jing Guo Yi Liu Hua-xuan you Department of Gynaecology Nursing West China Second University HospitalSichuan UniversityChengduSichuan 610041China

Objective:To investigate the prevalence of cancer-related depression and anxiety in western China among patients with ovarian cancer and analyze their influencing ***:In this prospective cross-sectional study,qualified patients were asked to fill in *** analysis and binary logistic regression analysis were used to test the associations among symptoms of depression and anxiety,coping styles,and influencing ***:A total of 270 ovarian cancer inpatients who met the criteria for participation in the study completed the *** levels of depression and anxiety that prevailed in ovarian cancer patients were 47.03%and 57.77%,*** them,90.38%of cancer-related anxiety patients and 91.33%of cancer-related depression patients showed mild *** chi-square test showed that there were statistically significant differences(P<0.05)in the fields of education level and income.T-test showed that cancer-related depression and anxiety were associated with coping style,and the difference had statistical significance(P<0.05).Furthermore,multivariate analysis showed that the education level and coping style were the independent influencing factors of depression and ***:The present study suggested that about half of the ovarian cancer patients had with depression and anxiety *** majority of the cancer-related depression and symptoms were *** level and coping style should be considered during the interventions of cancer-related depression and anxiety.

关键词： ovarian cancer depression anxiety coping style