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Systematic analysis of corporate environmental responsibility:elements,structure,function,and principles 被引量:4
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作者 Hong Wang 《Chinese Journal of Population,Resources and Environment》 2016年第2期96-104,共9页
Corporate Environmental Responsibility(CER) is the subsystem of Corporate Social Responsibility(CSR),which continues to increase prominence in the global economy.Nowadays,CER becomes more important in corporate sustai... Corporate Environmental Responsibility(CER) is the subsystem of Corporate Social Responsibility(CSR),which continues to increase prominence in the global economy.Nowadays,CER becomes more important in corporate sustainable development.Based on Carroll's pyramid mode of CSR,this article explores the systematic feature of CER.From a systematic perspective,it sorts out its elements,structure,function,and principles of CER.And the four levels of economic,legal,ethical,and charitable structure are emphasized.With these considerations interpreted into practice,success will be achieved in potential cost savings,technological innovation,increased public acceptance,and better relations with governments. 展开更多
关键词 Corporate Social responsibility(CSR) Corporate Environmental responsibility(CER) system structure FUNCTION PRINCIPLE
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Research on the Impact of Market Competition, Ownership Structure, and Corporate Social Responsibility
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作者 Li Huang Chaoyan Hu 《Proceedings of Business and Economic Studies》 2018年第3期17-22,共6页
This article takes companies listed from 2014 to 2016 as research objects,relies on principal–agent theory,stakeholder theories,and reputation theories,and examines the ownership structure,market competition,and corp... This article takes companies listed from 2014 to 2016 as research objects,relies on principal–agent theory,stakeholder theories,and reputation theories,and examines the ownership structure,market competition,and corporate social responsibility(CSR)using a multiple regression approach based on a hybrid ownership perspective.At the same time,the relationship between market competition and equity structure was studied.Research shows that product competition degree and CSR are in an inverted“U”relationship;ownership concentration is positively related to CSR;equity balance and CSR are negative.When related to market competition variables,the mixed-owned companies listed degree of ownership concentration are still positively related to CSR,and the linear relationship of negative balance of ownership balance becomes an inverted“U”-shaped curve relationship.The market competition has improved the restraint of CSR by the degree of ownership balance. 展开更多
关键词 Market COMPETITION EQUITY structure CORPORATE SOCIAL responsibility
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Investigations of the mechanical response of dummy HTPB propellant grain under ultrahigh acceleration overload conditions using onboard flight-test measurements
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作者 Yiming Zhang Ningfei Wang +3 位作者 Weihua Ma Ran Wang Long Bai Yi Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期473-484,共12页
In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measuremen... In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were performed.Two projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 g.The onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and analysed.Uniaxial compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching process.During the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant grain.The calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were observed.The dynamic mechanical response process of the dummy propellant grain was analysed in detail.The results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process. 展开更多
关键词 Gun-launched flight test Dummy HTPB propellant Onboard measurements Utrahigh overload Mechanical response
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Damage Detection of Offshore Jacket Structures Using Frequency Domain Selective Measurements 被引量:1
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作者 M. Kianian A.A. Golafshani E. Ghodrati 《Journal of Marine Science and Application》 2013年第2期193-199,共7页
The development of damage detection techniques for offshore jacket structures is vital to prevent catastrophic events. This paper applies a frequency response based method for the purpose of structural health monitori... The development of damage detection techniques for offshore jacket structures is vital to prevent catastrophic events. This paper applies a frequency response based method for the purpose of structural health monitoring. In efforts to fulfill this task, concept of the minimum rank perturbation theory has been utilized. The present article introduces a promising methodology to select frequency points effectively. To achieve this goal, modal strain energy ratio of each member was evaluated at different natural frequencies of structure in order to identify the sensitive frequency domain for damage detection. The proposed methodology opens up the possibility of much greater detection efficiency. In addition, the performance of the proposed method was evaluated in relation to multiple damages. The aforementioned points are illustrated using the numerical study of a two dimensional jacket platform, and the results proved to be satisfactory utilizing the proposed methodology. 展开更多
关键词 damage detection structural health monitoring frequency response function offshore jacket platform minimum rank perturbation theory element modal strain energy ratio
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Matrix test measurements of ground-borne vibration induced by the heavy-duty trains on embankment and cutting tracks in a loess area 被引量:3
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作者 Xie Qiang Wu Zhi-Hui +1 位作者 Dong Jie Zhong Shuai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第3期605-620,共16页
This paper presents a comparative analysis of ground vibration in three directions generated by a heavy-duty railway with various track sections.The vibration characteristics in the plane area were investigated by usi... This paper presents a comparative analysis of ground vibration in three directions generated by a heavy-duty railway with various track sections.The vibration characteristics in the plane area were investigated by using matrix test measurements.Acceleration peak attenuation was faster within 25 m from the embankment,and the high-frequency vibration attenuates faster with increased distance.For the cutting section with multi-stage soil slope,decay rate of acceleration was relatively larger.The acceleration level of the plane region ranged to 82.2-89.1 dB by the single C80 train.Yet the acceleration level caused by the C80 trains running parallel after meeting showed a distinct increment.The increment of the cutting section was much larger compared with the embankment section,with the increment ranging from 1.2-2.5 dB.In terms of the cutting section,Y direction acceleration was dominant closer to the track.Within 10-30 m of the track,the Y direction acceleration(perpendicular to the rail)decreased rapidly and became comparable to the X direction(parallel to the rail)and Z direction.Additionally,the cutting case generated a higher level of vibration in all three directions compared to the embankment,but as the distance from track increased,the deviation between acceleration gradually decreased. 展开更多
关键词 heavy-duty railway different track sections field measurement vibration response characteristics cutting slope
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Strong-field response time and its implications on attosecond measurement
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作者 Chao Chen Jiayin Che +3 位作者 Xuejiao Xie Shang Wang Guoguo Xin Yanjun Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第3期16-23,共8页
To measure and control the electron motion in atoms and molecules by the strong laser field on the attosecond time scale is one of the research frontiers of atomic and molecular photophysics. It involves many new phen... To measure and control the electron motion in atoms and molecules by the strong laser field on the attosecond time scale is one of the research frontiers of atomic and molecular photophysics. It involves many new phenomena and processes and raises a series of questions of concepts, theories, and methods. Recent studies show that the Coulomb potential can cause the ionization time lag(about 100 attoseconds) between instants of the field maximum and the ionization-rate maximum. This lag can be understood as the response time of the electronic wave function to the strong-field-induced ionization event. It has a profound influence on the subsequent ultrafast dynamics of the ionized electron and can significantly change the time–frequency properties of electron trajectory(an important theoretical tool for attosecond measurement). Here, the research progress of response time and its implications on attosecond measurement are briefly introduced. 展开更多
关键词 response time strong-field ionization Coulomb effect attosecond measurement
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Wind-Induced Response Characteristics of a Tall Building from GPS and Accelerometer Measurements 被引量:3
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作者 Cuilin Kuang Kenny Chung Sau Kwok +1 位作者 Peter Andrew Hitchcock Xiaoli Ding 《Positioning》 2011年第1期1-13,共13页
The main objectives of the research are to characterize the wind-induced resonant and slowly-varying (quasi-static) responses of a tall building under ambient wind excitations based on GPS measurements. The equipment ... The main objectives of the research are to characterize the wind-induced resonant and slowly-varying (quasi-static) responses of a tall building under ambient wind excitations based on GPS measurements. The equipment used includes two sets of orthogonally aligned accelerometers, two GPS receivers and an ultrasonic anemometer. The natural frequencies of the wind-induced vibration of the tall building are determined by carrying out spectral analysis of the measured time series of acceleration. The time series are also used to estimate the structural damping with the random decrement technique (RDT). The results show that GPS can be effectively used to measure the resonant and slowly-varying responses of tall buildings with 3D mode shapes under wind excitations. The results from the GPS and the accelerometers agree well with each other in both the time and frequency domains. 展开更多
关键词 GPS measurementS ACCELERATION Wind-induced RESPONSE Tall BUILDING
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Orientation effect on ground motion measurement for Mexican subduction earthquakes
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作者 H.P. Hong A. Pozos-Estrada R. Gomez 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期1-16,共16页
The existence of the principal directions of the ground motion based on Arias intensity is well-known. These principal directions do not necessarily coincide with the orientations of recording sensors or with the orie... The existence of the principal directions of the ground motion based on Arias intensity is well-known. These principal directions do not necessarily coincide with the orientations of recording sensors or with the orientations along which the ground motion parameters such as the peak ground acceleration and the pseudo-spectral acceleration (PSA) are maximum. This is evidenced by the fact that the maximum PSA at different natural vibration periods for horizontal excitations do not correspond to the same orientation. A recent analysis carried out for California earthquake records suggests that an orientation-dependent ground motion measurement for horizontal excitations can be developed. The main objective of this study is to investigate and provide seismic ground motion measurements in the horizontal plane, including bidirectional horizontal ground motions, for Mexican interplate and inslab earthquake records. Extensive statistical analyses of PSA are conducted for the assessment. The analysis results suggest that similar to the case of California records, the average behavior of the ratio of the PSA to the maximum resulting PSA can be approximated by a quarter of an ellipse in one quadrant; and that the ratio can be considered to be independent of the value of the maximum resulting PSA, earthquake magnitude, earthquake distance and the focal depth. Sets of response ratios and attenuation relationships that can be used to represent a bidirectional horizontal ground motion measurement for Mexican interplate and inslab earthquakes were also developed. 展开更多
关键词 orthogonal horizontal excitations bidirectional ground motion measure attenuation relationship pseudospectral acceleration (PSA) response ratio Mexican earthquake
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3-Dimensional Body Measurement Technology
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作者 周旭东 李艳梅 《Journal of Donghua University(English Edition)》 EI CAS 2002年第4期138-140,共3页
3 - dimensional body measurement technology, the basis of developing high technology in industry, accelerates digital development of aplparel industry. This paper briefly introduces the history of 3 - dimensional body... 3 - dimensional body measurement technology, the basis of developing high technology in industry, accelerates digital development of aplparel industry. This paper briefly introduces the history of 3 - dimensional body measurement technology, and recounts the principle and primary structure of some types of 3 - dimensional automatic body measurement system. With this understanding, it discusses prospect of 3- dimensional CAD and virtual technology used in apparel industry. 展开更多
关键词 3 - DIMENSIONAL BODY measurement technology digital apparel industry quick response virtual fitting apparel NAD
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Precision storage lifetime measurements of highly charged heavy ions in the CSRe storage ring using a Schottky resonator
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作者 Qian Wang Xin-Liang Yan +13 位作者 Guang-Yu Zhu Shahab Sanjari Li-Jun Mao He Zhao Yuri ALitvinov Rui-Jiu Chen Meng Wang Yu-Hu Zhang You-Jin Yuan Jun-Xia Wu Hong-Yang Jiao Yue Yu Zu-Yi Chen Yin-Fang Luo 《Nuclear Science and Techniques》 2025年第1期150-160,共11页
Schottky mass spectrometry utilizing heavy-ion storage rings is a powerful technique for the precise mass and decay half-life measurements of highly charged ions.Owing to the nondestructive ion detection features of S... Schottky mass spectrometry utilizing heavy-ion storage rings is a powerful technique for the precise mass and decay half-life measurements of highly charged ions.Owing to the nondestructive ion detection features of Schottky noise detectors,the number of stored ions in the ring is determined by the peak area in the measured revolution frequency spectrum.Because of their intrinsic amplitude-frequency characteristic(AFC),Schottky detector systems exhibit varying sensitivities at different frequencies.Using low-energy electron-cooled stored ions,a new method is developed to calibrate the AFC curve of the Schottky detector system of the Experimental Cooler Storage Ring(CSRe)storage ring located in Lanzhou,China.Using the amplitude-calibrated frequency spectrum,a notable refinement was observed in the precision of both the peak position and peak area.As a result,the storage lifetimes of the electron-cooled fully ionized^(56)Fe^(26+)ions were determined with high precision at beam energies of 13.7 and 116.4 MeV/u,despite of frequency drifts during the experiment.When electron cooling was turned off,the effective vacuum condition experienced by the 116.4 MeV/u^(56)Fe^(26+)ions was determined using amplitude-calibrated spectra,revealing a value of 2×10^(−10)mbar,which is consistent with vacuum gauge readings along the CSRe ring.The method reported herein will be adapted for the next-generation storage ring of the HIAF facility under construction in Huizhou,China.It can also be adapted to other storage ring facilities worldwide to improve precision and enhance lifetime measurements using many ions in the ring. 展开更多
关键词 Lifetime measurement Schottky mass spectrometry Sensitivity response Highly charged heavy ion Resonator UH vacuum Nondestructive diagnostics
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Synchrophasor Measurement Method Based on Cascaded Infinite Impulse Response and Dual Finite Impulse Response Filters
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作者 Boyu Zhao Hao Liu +1 位作者 Tianshu Bi Sudi Xu 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2024年第5期1345-1356,共12页
High-precision synchronized measurement data with short measurement latency are required for the applications of phasor measurement units(PMUs).This paper proposes a synchrophasor measurement method based on cascaded ... High-precision synchronized measurement data with short measurement latency are required for the applications of phasor measurement units(PMUs).This paper proposes a synchrophasor measurement method based on cascaded infinite impulse response(IIR)and dual finite impulse response(FIR)filters,meeting the M-class and P-class requirements in the IEC/IEEE 60255-118-1 standard.A low-group-delay IIR filter is designed to remove out-of-band interference components.Two FIR filters with different center frequencies are designed to filter out the fundamental negative frequency component and obtain synchrophasor estimates.The ratio of the amplitudes of the synchrophasor is used to calculate the frequency according to the one-to-one correspondence between the ratio of the amplitude frequency response of the FIR filters and the frequency.To shorten the response time introduced by IIR filter,a step identification and processing method based on the rate of change of frequency(RoCoF)is proposed and analyzed.The synchrophasor is accurately compensated based on the frequency and the frequency response of the IIR and FIR filters,achieving high-precision synchrophasor and frequency estimates with short measurement latency.Simulation and experiment tests demonstrate that the proposed method is superior to existing methods and can provide synchronized measurement data for M-class PMU applications with short measurement latency. 展开更多
关键词 Synchrophasor measurement frequency estimation infinite impulse response filter complex bandpass filter
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Acoustical properties of a 3D printed honeycomb structure filled with nanofillers:Experimental analysis and optimization for emerging applications
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作者 Jeyanthi Subramanian Vinoth kumar Selvaraj +3 位作者 Rohan Singh Ilangovan S Naresh Kakur Ruban Whenish 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期248-258,共11页
The novelty of this research lies in the successful fabrication of a 3D-printed honeycomb structure filled with nanofillers for acoustic properties,utilizing an impedance tube setup in accordance with ASTM standard E ... The novelty of this research lies in the successful fabrication of a 3D-printed honeycomb structure filled with nanofillers for acoustic properties,utilizing an impedance tube setup in accordance with ASTM standard E 1050-12.The Creality Ender-3,a 3D printer,was used for printing the honeycomb structures,and polylactic acid(PLA)material was employed for their construction.The organic,inorganic,and polymeric compounds within the composites were identified using fourier transformation infrared(FTIR)spectroscopy.The structure and homogeneity of the samples were examined using a field emission scanning electron microscope(FESEM).To determine the sound absorption coefficient of the 3D printed honeycomb structure,numerous samples were systematically developed using central composite design(CCD)and analysed using response surface methodology(RSM).The RSM mathematical model was established to predict the optimum values of each factor and noise reduction coefficient(NRC).The optimum values for an NRC of 0.377 were found to be 1.116 wt% carbon black,1.025 wt% aluminium powder,and 3.151 mm distance between parallel edges.Overall,the results demonstrate that a 3Dprinted honeycomb structure filled with nanofillers is an excellent material that can be utilized in various fields,including defence and aviation,where lightweight and acoustic properties are of great importance. 展开更多
关键词 3D printing Honeycomb structure ACOUSTICS Field emission scanning electron microscope Response surface methodology
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Numerical analysis on seismic performance of underground structures in liquefiable interlayer sites from centrifuge shaking table test
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作者 Yan Guanyu Xu Chengshun +2 位作者 Zhang Zihong Du Xiuli Wang Xuelai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期781-798,共18页
When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response... When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response of underground structures in liquefiable interlayer sites,and a valid numerical model was obtained through simulation model test.Finally,the calibrated numerical model was used to perform further research on the influence of various distribution characteristics of liquefiable interlayers on the seismic reaction of underground structures.The key findings are as follows.The structure faces the most unfavorable condition once a liquefiable layer is located in the middle of the underground structure.When a liquefiable layer exists in the middle of the structure,the seismic reactions of both the underground structure and model site will increase with the rise of the thickness of the liquefiable interlayer.The inter-story drift of the structure in the non-liquefiable site is much smaller than that in the liquefiable interlayer site.The inter-story drift of the structure is not only associated with the site displacement and the soil-structure stiffness ratio but also closely associated with the slippage of the soil-structure contact interface under the condition of large deformation of the site. 展开更多
关键词 centrifuge shaking table test underground structure liquefiable interlayer sites seismic response validation of numerical model
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Dynamic Response of Tensile Membrane Structure under Coupling Effect of Wind and Rain
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作者 Weiju Song Heyuan Yang Jie Chen 《Journal of Applied Mathematics and Physics》 2024年第11期3816-3826,共11页
Because of the small stiffness and high flexibility, the tension membrane structure is easy to relax and damage or even destroy under the action of external load, which leads to the occurrence of engineering accidents... Because of the small stiffness and high flexibility, the tension membrane structure is easy to relax and damage or even destroy under the action of external load, which leads to the occurrence of engineering accidents. In this paper, the damped nonlinear vibration of tensioned membrane structure under the coupling action of wind and rain is approximately solved, considering the geometric nonlinearity of membrane surface deformation and the influence of air damping. Applying von Karman’s large deflection theory and D’Alembert’s principle, the governing equations are established for an analytical solution, and the experimental results are compared with the analytical results. The feasibility of this method is verified, which provides some theoretical reference for practical membrane structure engineering design and maintenance. 展开更多
关键词 Tension Membrane structure Wind and Rain Coupling Effect Dynamic Response Nonlinear Vibration
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Study on the Influence of Aspect Ratio on the Seismic Response and Overturning Resistance of a New Staggered Story Isolated Structure
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作者 Tiange Zhao Dewen Liu 《World Journal of Engineering and Technology》 2024年第3期617-634,共18页
The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stif... The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stiffness of the structure, leading to significant tensile and compressive stresses in the isolated bearings. To study the effect of aspect ratio on the seismic response and overturning resistance of a new staggered story isolated structure, three models with different aspect ratios were established. Nonlinear time-history analysis of the three models was conducted using ETABS finite element software. The results indicate that the overturning moment and overturning resistance moment of the superstructure in the new staggered story isolated structure increase with an increasing aspect ratio. However, the increase in the overturning moment of the superstructure is much greater than the increase in the overturning resistance moment, resulting in a decrease in the overturning resistance ratio of the superstructure with an increasing aspect ratio. The overturning moment and overturning resistance moment of the substructure in the new staggered story isolated structure decrease with an increasing aspect ratio. However, the decrease in the overturning moment of the substructure is greater than the decrease in the overturning resistance moment, leading to an increase in the overturning resistance ratio of the substructure with an increasing aspect ratio. The decrease in the overturning resistance ratio of the superstructure in the new staggered story isolated structure is much greater than the increase in the overturning resistance ratio of the substructure. Therefore, as the aspect ratio of the overall structure increases, the overturning resistance ratio of the superstructure and the entire structure decreases. 展开更多
关键词 Aspect Ratio A New Staggered Story Isolated structure Seismic Response Overturning Resistance Ratio Isolated Bearing
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The MDOF equivalent linear system and its applications in seismic analysis and design of framed structures
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作者 E.V.Muho N.A.Kalapodis +1 位作者 G.A.Papagiannopoulos D.E.Beskos 《Resilient Cities and Structures》 2024年第4期107-125,共19页
This paper reviews the applications of the multi degree-of-freedom(MDOF)equivalent linear system in seismic analysis and design of planar steel and reinforced concrete framed structures.An equivalent MDOF linear struc... This paper reviews the applications of the multi degree-of-freedom(MDOF)equivalent linear system in seismic analysis and design of planar steel and reinforced concrete framed structures.An equivalent MDOF linear structure,analogous to the original MDOF nonlinear structure,is constructed,which has the same mass and elastic stiffness as the original structure and modal damping ratios that account for the effects of geometrical and material nonlinearities.The equivalence implies a balance between the viscous damping work of the equivalent linear structure and that of the nonlinearities in the original nonlinear structure.This work balance is established with the aid of a transfer function in the frequency domain.Thus,equivalent modal damping ratios can be explicitly determined in terms of the period and deformation levels of the structure as well as the soil types.Use of these equivalent modal damping ratios can help address a variety of seismic analysis and design problems associated with planar steel and reinforced concrete framed structures in a rational and accurate manner.These include force-based seismic design with the aid of acceleration response spectra characterized by high amounts of damping,improved direct displacement-based seismic design and the development of advanced seismic intensity measures.The equivalent modal damping ratios are also utilized in the context of linear modal analysis for the definition and construction of the MDOF response spectrum.Furthermore,the equivalent modal damping ratios are employed in a seismic retrofit method for steel-framed structures with viscous dampers.Finally,it is demonstrated that modal behavior(or strength reduction)factors can be easily constructed based on these modal damping ratios for a more rational and accurate force-based seismic design,including the determination of inelastic displacement profiles. 展开更多
关键词 Seismic analysis Seismic design Steel-framed structures Reinforced concrete-framed structures MDOF equivalent linear system Modal damping ratios Modal strength reduction factors Seismic intensity measures MDOF response spectrum
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强震下基础隔震结构软碰撞防护研究
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作者 金建敏 刘彦辉 +1 位作者 陈鹏 周惠蒙 《世界地震工程》 北大核心 2025年第1期165-174,共10页
针对基础隔震结构在超罕遇地震的强震作用下隔震层位移超限问题,采用已有弹性软碰撞防护装置和所研发的弹塑性软碰撞防护装置。考虑上部结构非线性,建立设置两类软碰撞防护装置的基础隔震结构模型,进行不同地震设防水准地震作用下设置... 针对基础隔震结构在超罕遇地震的强震作用下隔震层位移超限问题,采用已有弹性软碰撞防护装置和所研发的弹塑性软碰撞防护装置。考虑上部结构非线性,建立设置两类软碰撞防护装置的基础隔震结构模型,进行不同地震设防水准地震作用下设置两类软碰撞防护装置的基础隔震结构的非线性时程分析,研究不同防护距离、不同力学性能参数的弹性及弹塑性软碰撞防护装置对隔震层限位效果及上部结构地震响应的影响。结果表明:在超罕遇地震的强震作用下,两类软碰撞防护装置均可起到限制隔震层位移的作用;与仅能为隔震层附加刚度的弹性软碰撞装置相比较,能够为隔震层同时附加刚度和阻尼力的弹塑性软碰撞防护装置,隔震层限位效果和上部结构层间位移角响应控制效果均较优。合理设置弹性及弹塑性软碰撞防护装置,在将隔震层位移限制在规范限值以内的同时,上部结构最大加速度可限制在地震波输入峰值50%以下,确保基础隔震结构发挥正常的隔震功能。 展开更多
关键词 基础隔震结构 隔震层位移 软碰撞防护 限位效果 地震响应
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船冰多次碰撞下极地航行船舶舷侧结构动态响应研究
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作者 姜河蓉 姜金辉 +1 位作者 杨泽文 袁昱超 《舰船科学技术》 北大核心 2025年第1期8-13,共6页
近年来全球变暖的加剧使得北极航道的开放更具可行性,为分析极地船舶航行过程中的冰载荷及船体结构响应特性,本文针对船体舷侧结构与浮冰场多次碰撞的场景开展数值仿真研究。参考现阶段浮冰观测统计经验,建立船体舷侧结构-浮冰场相互作... 近年来全球变暖的加剧使得北极航道的开放更具可行性,为分析极地船舶航行过程中的冰载荷及船体结构响应特性,本文针对船体舷侧结构与浮冰场多次碰撞的场景开展数值仿真研究。参考现阶段浮冰观测统计经验,建立船体舷侧结构-浮冰场相互作用有限元数值模型,在不同碰撞角度与不同浮冰密集度下开展仿真计算,分析船冰连续多次碰撞过程中碰撞力、能量及响应数据,研究碰撞角度和浮冰场密集度对浮冰载荷及船体舷侧结构响应特性的影响规律。结果表明,船冰多次相互作用下的结构响应规律与船冰单次作用存在一定差异,碰撞角度与浮冰场密集度参数对船冰碰撞力与船体舷侧结构响应特征影响呈现出一定的规律。本文研究内容对极地航行船舶舷侧结构的安全性设计具有参考价值。 展开更多
关键词 船-冰多次碰撞 舷侧结构 结构响应 非线性有限元方法
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企业社会责任对劳动力结构升级的影响研究
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作者 陶欣欣 郝闻汉 马丽伟 《企业经济》 北大核心 2025年第1期15-25,共11页
在以新发展格局重塑经济新优势、推动经济发展的关键时期,优质劳动力对我国社会和企业的发展起着至关重要的推动作用。本文探讨企业社会责任对劳动力结构优化升级的影响及作用机制,发现企业社会责任有助于促进企业劳动力结构升级;提高... 在以新发展格局重塑经济新优势、推动经济发展的关键时期,优质劳动力对我国社会和企业的发展起着至关重要的推动作用。本文探讨企业社会责任对劳动力结构优化升级的影响及作用机制,发现企业社会责任有助于促进企业劳动力结构升级;提高企业声誉和缓解融资约束是企业社会责任影响劳动力结构升级的主要路径;在技术密集型企业,二者的正向关系更显著。因此,企业应更加积极、主动地承担社会责任;努力维持与利益相关者之间的良好关系,提高企业声誉;政府及金融机构应加大对企业的支持力度,缓解企业融资约束,实现企业劳动力结构优化升级,推动企业和社会的高质量发展。 展开更多
关键词 企业社会责任 劳动力结构升级 优质劳动力 声誉 融资约束
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落石作用下岩溶隧道衬砌结构响应试验研究
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作者 祝方才 何文 +2 位作者 杨志佳 刘冬 罗睿 《湖南工业大学学报》 2025年第3期1-7,共7页
以四川某高速公路岩溶隧道为工程背景,采用相似理论构建室内缩尺模型,研究了不同工况下落石对隧道护拱和衬砌结构的影响。通过高速摄影仪捕捉落石掉落瞬间的运动轨迹,同时利用应变片和动态信号测试分析系统监测了衬砌结构的应变响应,并... 以四川某高速公路岩溶隧道为工程背景,采用相似理论构建室内缩尺模型,研究了不同工况下落石对隧道护拱和衬砌结构的影响。通过高速摄影仪捕捉落石掉落瞬间的运动轨迹,同时利用应变片和动态信号测试分析系统监测了衬砌结构的应变响应,并利用加速度传感器研究了结构的加速度响应。研究发现,落石的反弹能量逐渐衰减导致其反弹高度减小;衬砌结构拱顶位置的加速度与位移响应明显,且随着落石质量和下落高度增加,衬砌结构的应变变化显著增加。 展开更多
关键词 岩溶隧道 支护结构 落石 动力响应 缩尺模型试验
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