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A Selective‑Response Hypersensitive Bio‑Inspired Strain Sensor Enabled by Hysteresis Effect and Parallel Through‑Slits Structures
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作者 Qun Wang Zhongwen Yao +8 位作者 Changchao Zhang Honglie Song Hanliang Ding Bo Li Shichao Niu Xinguan Huang Chuanhai Chen Zhiwu Han Luquan Ren 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期139-153,共15页
Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into... Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into one flexible strain sensor remains a huge challenge.Herein,inspired by the hysteresis strategy of the scorpion slit receptor,a bio-inspired flexible strain sensor(BFSS)with parallel through-slit arrays is designed and fabricated.Specifically,BFSS consists of conductive monolayer graphene and viscoelastic styrene–isoprene–styrene block copolymer.Under the synergistic effect of the bio-inspired slit structures and flexible viscoelastic materials,BFSS can achieve both hypersensitivity and highly selective frequency response.Remarkably,the BFSS exhibits a high gage factor of 657.36,and a precise identification of vibration frequencies at a resolution of 0.2 Hz through undergoing different morphological changes to high-frequency vibration and low-frequency vibration.Moreover,the BFSS possesses a wide frequency detection range(103 Hz)and stable durability(1000 cycles).It can sense and recognize vibration signals with different characteristics,including the frequency,amplitude,and waveform.This work,which turns the hysteresis effect into a"treasure,"can provide new design ideas for sensors for potential applications including human–computer interaction and health monitoring of mechanical equipment. 展开更多
关键词 Bio-inspired strain sensors Hysteresis effect HYPERSENSITIVITY Selective frequency response Health monitoring applications
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Influence of the boundary effect on the mechanical response test of pavement cushion under the wetting effect of silt
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作者 Luo Qiqi Yu Qian +3 位作者 Zhang Sheng Ma Xinyan Ye Xinyu Du Yinfei 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期266-274,共9页
Through a self-developed model test system,the mechanical properties of silt and the deformation characteristics of airport runways were investigated during the period of subgrade wetting.Based on the test results,the... Through a self-developed model test system,the mechanical properties of silt and the deformation characteristics of airport runways were investigated during the period of subgrade wetting.Based on the test results,the reliability of the numerical simulation results was verified.Numerical models with different sizes were established.Under the same cushion parameter and loading width ranges,the effects of the cushion parameters and loading conditions on the mechanical responses of the cushion before and after subgrade wetting were analyzed.The results show that the internal friction angles of silt with different wetting degrees are approximately 34°.The cohesion is from 8 to 44 kPa,and the elastic modulus is from 15 to 34 MPa.Before and after subgrade wetting,the variation rates of the cushion horizontal tensile stresses with the same cushion parameters and loading width ranges are different under the influence of boundary effects.After subgrade wetting,the difference in the variation rates of the cushion horizontal tensile stresses under the same cushion parameter range decreases compared with that before subgrade wetting;however,this difference increases under the same loading width range.Before and after subgrade wetting,the influence of the boundary effect on the mechanical response evaluation of the cushion is not beneficial for optimizing the pavement design parameters.When the cushion thickness is more than 0.25 m,the influence of the boundary effect can be disregarded. 展开更多
关键词 pavement cushion silt subgrade WETTING boundary effect mechanical response
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Effect of corporate social responsibility on creation of added value 被引量:2
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作者 FANG Xiao-zhi YANG Chun-qing YU Jun 《Ecological Economy》 2016年第4期376-383,共8页
In the process of financial management and operation, a firm should not only aim to maximize its shareholders' benefits, but also consider the interests of all stakeholders. Bearing social responsibility to each s... In the process of financial management and operation, a firm should not only aim to maximize its shareholders' benefits, but also consider the interests of all stakeholders. Bearing social responsibility to each stakeholder to a certain extent and pursuing harmonious social development are fully consistent with the concept of China's building a harmonious socialist society. Furthermore, added value also reflects the idea of social responsibility Based on the relational contract theory, the paper divides stakeholders into staff and shareholders under relational contracts, creditors, suppliers and consumers under transactional contracts and governments and communities under special contracts. The paper details the effect mechanism of a firm's bearing social responsibilities to each stakeholder on the creation of added value respectively, and considers that corporate social responsibilities should be included in the system for creating added value to theoretically support firm managers to fulfill social responsibilities. 展开更多
关键词 corporate social responsibilities added value effect mechanism
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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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Application Effect of Hierarchical Group Responsibility System Holistic Nursing in Department of Gastroenterology
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作者 Fang Yan Jinglan Luo Guiyan Wen 《Journal of Clinical and Nursing Research》 2021年第2期66-69,共4页
Objective:To analyze the application effect of hierarchical group responsibility system of holistic nursing in Department of Gastroenterology.Methods:655 patients in our hospital from August 2020 to January 2021 were ... Objective:To analyze the application effect of hierarchical group responsibility system of holistic nursing in Department of Gastroenterology.Methods:655 patients in our hospital from August 2020 to January 2021 were selected as the research objects.They were randomly divided into experimental group(328 cases)and control group(327 cases)to explore nursing satisfaction,nursing quality score and clinical symptoms before and after nursing.Results:In the experimental group,266 cases(81.10%)were very satisfied,33 cases(10.06%)were satisfied and 29 cases(8.84%)were dissatisfied.The total number of satisfied cases(very satisfied+satisfied)was 299 cases(91.16%);In the control group,167 cases(51.07%)were very satisfied,63 cases(19.27%)were satisfied,97 cases(29.66%)were dissatisfied,and 230 cases(70.34%)were satisfied.The nursing satisfaction of the experimental group was significantly higher than that of the control group;The nursing quality score of the experimental group was(91.67±0.66),and that of the control group was(71.66±0.88),which was significantly higher than that of the control group;The clinical symptom score of the experimental group was(2.42±0.32),and that of the control group was(4.66±1.11),which was significantly better than that of the control group.Conclusion:The application of hierarchical group responsibility holistic nursing mode in gastroenterology department can not only improve the nursing satisfaction of patients,but also improve the quality of nursing,promote the good development of patients'condition,and provide a comfortable treatment environment for patients,which is worthy of clinical promotion. 展开更多
关键词 Hierarchical group Holistic nursing with responsibility system GI Medicine Nursing effect
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Effects of urethane on the response properties of visual cortical neurons in young adult and old cats 被引量:3
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作者 彭青松 周俊 +2 位作者 施夏明 化国鹏 华田苗 《Zoological Research》 CAS CSCD 北大核心 2011年第3期337-342,共6页
Previous studies have shown that visual cortical neurons in old mammals exhibit higher spontaneous activity,higher responsiveness to visual stimuli,and lower selectivity for stimulus orientations and motion directions... Previous studies have shown that visual cortical neurons in old mammals exhibit higher spontaneous activity,higher responsiveness to visual stimuli,and lower selectivity for stimulus orientations and motion directions than did neurons in young adult counterparts.However,whether the responsive difference in cortical neurons between young and old animals resulted from different effects induced by anesthetics has remained unclear.To clarify this issue,we recorded the response properties of individual neurons in the primary visual cortex of old and young adult cats while systematically varying the anesthesia level of urethane,a widely used anesthetic in physiology experiments.Our results showed that cumulatively administrating 50 mg and 100 mg of urethane upon the minimal level of urethane required to anesthetize an old or young adult cat did not significantly alter the degree of neuronal response selectivity for stimulus orientations and motion directions nor significantly change the visually-driven response and spontaneous activity of neurons in old and young adult cats.Cumulatively administrating 150 mg of urethane decreased neuronal responsiveness similarly in both age groups.Therefore,urethane appears to exert similar effects on neuronal response properties of old and young adult animals. 展开更多
关键词 URETHANE Anesthesia effects Neuronal response properties Primary visual cortex Young adult cats Old cats
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Simulation of the Radiative Effect of Black Carbon Aerosols and the Regional Climate Responses over China 被引量:21
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作者 吴涧 蒋维楣 +3 位作者 符淙斌 苏炳凯 刘红年 汤剑平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第4期637-649,共13页
As part of the development work of the Chinese new regional climate model (RIEMS), the radiative process of black carbon (BC) aerosols has been introduced into the original radiative procedures of RIEMS, and the trans... As part of the development work of the Chinese new regional climate model (RIEMS), the radiative process of black carbon (BC) aerosols has been introduced into the original radiative procedures of RIEMS, and the transport model of BC aerosols has also been established and combined with the RIEMS model. Using the new model system, the distribution of black carbon aerosols and their radiative effect over the China region are investigated. The influences of BC aerosole on the atmospheric radiative transfer and on the air temperature, land surface temperature, and total rainfall are analyzed. It is found that BC aerosols induce a positive radiative forcing at the top of the atmosphere (TOA), which is dominated by shortwave radiative forcing. The maximum radiative forcing occurs in North China in July and in South China in April. At the same time, negative radiative forcing is observed on the surface. Based on the radiative forcing comparison between clear sky and cloudy sky, it is found that cloud can enforce the TOA positive radiative forcing and decrease the negative surface radiative forcing. The responses of the climate system in July to the radiative forcing due to BC aerosols are the decrease in the air temperature in the middle and lower reaches of the Changjiang River and Huaihe area and most areas of South China, and the weak increase or decrease in air temperature over North China. The total rainfall in the middle and lower reaches of the Changjiang River area is increased, but it decreased in North China in July. 展开更多
关键词 black carbon aerosols radiative effect Climate responses RIEMS model
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Effects of topography on dynamic responses of single piles under vertical cyclic loading 被引量:8
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作者 QU Li-ming DING Xuan-ming +2 位作者 WU Chong-rong LONG Yong-hong YANG Jin-chuan 《Journal of Mountain Science》 SCIE CSCD 2020年第1期230-243,共14页
This paper describes model tests of single piles subjected to vertical cyclic compressive loading for three kinds of topography: sloping ground, level ground, and inclined bedrock. Comprehensive dynamic responses invo... This paper describes model tests of single piles subjected to vertical cyclic compressive loading for three kinds of topography: sloping ground, level ground, and inclined bedrock. Comprehensive dynamic responses involving cyclic effects and vibration behaviours are studied under various load combinations of dynamic amplitude, mean load,frequency and number of cycles. Test results show that permanent settlement can generally be predicted with a quadratic function or power function of cycles.Sloping ground topography produces more pronounced settlement than level ground under the same load condition. For vibration behaviour,displacement amplitude is weakly affected by the number of cycles, while load amplitude significantly influences dynamic responses. Test results also reveal that increasing load amplitude intensifies nonlinearity and topography effects. The strain distribution in a pile and soil stress at the pile tip are displayed to investigate the vibration mechanism accounting for sloping ground effects. Furthermore, the dynamic characteristics among three kinds of topography in the elastic stage are studied using a three-dimensional finite method. Numerical results are validated by comparing with experimental results for base inclination topography. An inclined soil profile boundary causes non-axisymmetric resultant deformation, though a small difference in vertical displacement is observed. 展开更多
关键词 PILE Model test Dynamic response Permanent settlement Vibration displacement Topography effects
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Seismic response analysis of continuous rigid frame bridge considering canyon topography effects under incident SV waves 被引量:8
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作者 Guoliang Zhou Xiaojun Li Xingjun Qi 《Earthquake Science》 CSCD 2010年第1期53-61,共9页
To evaluate the importance of the canyon topography effects on large structures, based on a rigid frame bridge across a 137-m-deep and 600-m-wide canyon, the seismic response of the canyon site is analyzed using a two... To evaluate the importance of the canyon topography effects on large structures, based on a rigid frame bridge across a 137-m-deep and 600-m-wide canyon, the seismic response of the canyon site is analyzed using a two-dimensional finite element model under different seismic SV waves with the assumptions of vertical incidence and oblique incidence to obtain the ground motions, which are used as the excitation input on the pier foundations of the bridge with improved large mass method. The results indicate that canyon topography has significant influences on the ground motions in terms of inci- dent angle. The peak ground acceleration values vary greatly from the bottom of the canyon to the upper comers. Under ver- tical incident SV waves, at the upper comers of canyon the peak ground accelerations greatly increase; whereas the peak ground accelerations diminish at the bottom comers of canyon. Under oblique incident SV waves, the shaking of the canyon slope perpendicular to the incidence direction is much more severe than that of the opposite side of canyon. And the ground surface has been characterized by larger deformations in the case of oblique incident waves. It is also concluded that the low piers and frame of the continuous rigid frame bridge ape more sensitive to the multi-support seismic excitations than the flexible high piers. The canyon topography as well as the oblique incidence of the waves brings the continuous rigid frame bridge severe responses, which should be taken into account in bridge design. 展开更多
关键词 rigid frame bridge canyon topography effect multi-support excitation improved large-mass method seismic response
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A time-domain nonlinear effective-stress non-Masing approach of ground response analysis of Guwahati city, India 被引量:2
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作者 Devdeep Basu Madhulatha Boga Arindam Dey 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第1期61-75,共15页
The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influen... The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influence of soil characteristics on the propagating seismic stress waves from the bedrock level to the ground surface during an earthquake. For the northeastern region of India, located in the highest seismic zone in the country, conducting an extensive GRA study is of prime importance. Conventionally, most of the GRA studies are carried out using the equivalent linear method, which, being a simplistic approach, cannot capture the nonlinear behavior of soil during seismic shaking. This paper presents the outcomes of a one-dimensional effective stress based nonlinear GRA conducted for Guwahati city(located in northeast India) incorporating the non-Masing load/unload/reload characteristics. The various ground response parameters evaluated from this study help in assessing the ground shaking, soil amplification, and site responses expected in this region. 2D contour maps, which are representative of the distribution of some of these parameters throughout Guwahati city, are also developed. The results presented herein can serve as guidelines for the design of foundations and superstructures in this region. 展开更多
关键词 GROUND responsE analysis nonlinear effective STRESS APPROACH non-masing criteria GROUND responsE parameters soil amplification
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The Dynamical Behavior of a Predator-Prey System with Holling Type II Functional Response and Allee Effect 被引量:4
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作者 Shuangte Wang Hengguo Yu +1 位作者 Chuanjun Dai Min Zhao 《Applied Mathematics》 2020年第5期407-425,共19页
In this paper, we mainly considered the dynamical behavior of a predator-prey system with Holling type II functional response and Allee-like effect on predator, including stability analysis of equilibria and Hopf bifu... In this paper, we mainly considered the dynamical behavior of a predator-prey system with Holling type II functional response and Allee-like effect on predator, including stability analysis of equilibria and Hopf bifurcation. Firstly, we gave some sufficient conditions to guarantee the existence, the local and global stability of equilibria as well as non-existence of limit cycles. By using the cobweb model, some cases about the existence of interior equilibrium are also illustrated with numerical outcomes. These existence and stability conclusions of interior equilibrium are also suitable in corresponding homogeneous reaction-diffusion system subject to the Neumann boundary conditions. Secondly, we theoretically deduced that our system has saddle-node bifurcation, transcritical bifurcation and Hopf bifurcation under certain conditions. Finally, for the Hopf bifurcation, we choose d as the bifurcation parameter and presented some numerical simulations to verify feasibility and effectiveness of the theoretical derivation corresponding to the existence of yk, respectively. The Hopf bifurcations are supercritical and limit cycles generated by the critical points are stable. 展开更多
关键词 PREDATOR-PREY System HOLLING Type II FUNCTIONAL response Allee effect Stability HOPF BIFURCATION
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Effect of the Transient Response in Si/Ge Parallelizing PN Junction 被引量:10
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作者 Weiqi HUANGt and Chaogang CHEN(Department of Physics, Guizhou Educational College, Guiyan 550003, China)Ergang CHEN(Department of Physics, Yunnan University, Kunming 650091, China)To whom correspondence should be addressed 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第4期383-383,共1页
There are some new results about photovoltaic transient response in the new effect. We suggest a theoretical model to explain the effect reasonably. The theoretical calculation results agree with that in experiments.
关键词 PN SI Ge effect of the Transient response in Si/Ge Parallelizing PN Junction
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ELECTRO-THERMAL EFFECTS AND DEFORMATION RESPONSE OF CARBON FIBER MAT CEMENT BEAMS 被引量:2
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作者 Zhu Sirong Li Zhuoqiu Song Xianhui (Department of Engineering Structures and Mechanics,Wuhan University of Technology,Wuhan 430070,China) 《Acta Mechanica Solida Sinica》 SCIE EI 2003年第4期359-365,共7页
A carbon fiber mat is a sheet composed of intercrossing short carbon fibers,which has more stable and lower electrical resistivity compared with dispersed short carbon fiber mixed in cement.Thereby carbon fiber mat ce... A carbon fiber mat is a sheet composed of intercrossing short carbon fibers,which has more stable and lower electrical resistivity compared with dispersed short carbon fiber mixed in cement.Thereby carbon fiber mat cement could exhibit obvious electro-thermal effect.When electrified,the temperature of composite structures made up of cement mortar and carbon fiber mat will rise rapidly.If the temperature field is not uniform,temperature difference will cause structures to deform,which can be used to adjust the deformation of structures.The temperature field and deformation response driven by the electro-thermal effects of a type of carbon fiber mat cement beams are studied.Firstly,the temperature and deformation responses are studied using theories of thermal conduction and elasticity.Secondly,experimental results are given to verify the theoretical solution.These two parts lay the foundation for temperature and deformation adjustment. 展开更多
关键词 carbon fiber mat cement electro-thermal effect deformation response
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Study on the effect of ground motion direction on the response of engineering structure 被引量:1
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作者 Sun Menghan Fan Feng +1 位作者 Sun Baitao Zhi Xudong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第4期649-656,共8页
Due to the randomness of earthquake wave magnitude and direction, and the uncertain direction of strong axis and weak axis in the construction of engineering structures, the effect of the direction of ground motion on... Due to the randomness of earthquake wave magnitude and direction, and the uncertain direction of strong axis and weak axis in the construction of engineering structures, the effect of the direction of ground motion on a structure are studied herein. Ground motion records usually contain three vertical ground motion data, which are obtained by sensors arranged in accordance with the EW (East -West) direction, NS (South- North) direction and perpendicular to the surface (z) direction, referring to the construction standard of seismic stations. The seismic records in the EW and NS directions are converted to Cartesian coordinates in accordance with the rotation of θ = 0°-180°, and consequently, a countless group of new ground motion time histories are obtained. Then, the characteristics of the ground motion time history and response spectrum of each group were studied, resulting in the following observations: (1) the peak and phase of ground motion are changed with the rotation of direction θ, so that the direction θ of the maximum peak ground motion can be determined; (2) response spectrum values of each group of ground motions change along with the direction θ, and their peak, predominant period and declining curve are also different as the changes occur; then, the angle θ in the direction of the maximum peak value or the widest predominant period can be determined; and (3) the seismic response of structures with different directions of ground motion inputs has been analyzed under the same earthquake record, and the results show the difference. For some ground motion records, such as the Taft seismic wave, these differences are significant. Next, the Lushan middle school gymnasium structure was analyzed and the calculation was checked using the proposed method, where the internal force of the upper space truss varied from 25% to 28%. The research results presented herein can be used for reference in choosing the ground motion when checking the actual damage to structures following earthquakes and explaining the seismic damage. Meanwhile, it also provides a reference value for research into the most severe ground motion. 展开更多
关键词 direction of grotmd motion structure effect coordinate transformation response spectrum
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Effective AC response of a nonlinear spherical coated composite 被引量:1
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作者 郝艳花 陈小刚 +1 位作者 侯睿 王瑞 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期471-476,共6页
An effective nonlinear response of a nonlinear composite with spherical coated inclusions randomly embedded in a host medium under the action of an external AC electric field, Ea= E1 sin(wt) + E3 sin(3wt), is inv... An effective nonlinear response of a nonlinear composite with spherical coated inclusions randomly embedded in a host medium under the action of an external AC electric field, Ea= E1 sin(wt) + E3 sin(3wt), is investigated using a perturbation method. The local potentials of the composite at higher harmonics are given both in the region of local inclusion particles and in the local host region under the external AC electric field. All effective nonlinear responses of the composite and the relationship between the effective nonlinear responses at the fundamental frequency and third harmonics are also studied for spherical coated inclusion in a dilute limit. 展开更多
关键词 nonlinear composite effective nonlinear response coated composite AC electric field
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Effective stress analysis method of seismic response for high tailings dam 被引量:3
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作者 柳厚祥 李宁 +2 位作者 廖雪 吴从师 潘旭东 《Journal of Central South University of Technology》 EI 2007年第1期129-134,共6页
Based on the analysis method for tailings dam in upstream raising method presently used in metallurgy and nonferrous metals tailings depository in the world, an effective stress analysis method of seismic response for... Based on the analysis method for tailings dam in upstream raising method presently used in metallurgy and nonferrous metals tailings depository in the world, an effective stress analysis method of seismic response for high tailings dam was developed according to the results of engineering geological exploration, static and dynamic test and stability analysis on Baizhishan tailing dam 113.5 m high. The law of generation, diffusion and dissipation of seismic pore water pressure during and after earthquake was investigated, and the results of tailings dam’s acceleration, seismic dynamic stress and pore water pressure were obtained. The results show that the seismic stability and liquefaction resistance of high tailings dam are strengthened remarkably, and the scope and depth of liquefaction area at the top of dam are reduced greatly. The interior stress is compressive stress, the stress level of every element is less than 1.0 and the safety coefficient of every element is greater than 1.0. The safety coefficient against liquefaction of every element of tailing dam is greater than 1.5 according to the effective stress analysis of seismic response by finite element method. The calculated results prove that liquefaction is the main reason of seismic failure of high tailing dams, and the effect of seismic inertia forces on high tailing dams’ stability during earthquake is secondary reason. 展开更多
关键词 tailings dam seismic response effective stress nonlinear analysis against liquefaction upstream raising method
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Estimation of spectral responses and chlorophyll based on growth stage effects explored by machine learning methods 被引量:2
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作者 Dehua Gao Lang Qiao +5 位作者 Lulu An Ruomei Zhao Hong Sun Minzan Li Weijie Tang Nan Wang 《The Crop Journal》 SCIE CSCD 2022年第5期1292-1302,共11页
Estimation of leaf chlorophyll content(LCC) by proximal sensing is an important tool for photosynthesis evaluation in high-throughput phenotyping. The temporal variability of crop biochemical properties and canopy str... Estimation of leaf chlorophyll content(LCC) by proximal sensing is an important tool for photosynthesis evaluation in high-throughput phenotyping. The temporal variability of crop biochemical properties and canopy structure across different growth stages has great impacts on wheat LCC estimation, known as growth stage effects. It will result in the heterogeneity of crop canopy at different growth stages, which would mask subtle spectral response of biochemistry variations. This study aims to explore spectral responses on the growth stage effects and establish LCC models suited for different growth stages. A total number of 864 pairwise samples of wheat canopy spectra and LCC values with 216 observations of each stage were sampled at the tillering, jointing, booting and heading stages in 2021. Firstly, statistical analysis of LCC and spectral response presented different distribution traits and typical spectral variations peak at 470, 520 and 680 nm. Correlation analysis between LCC and reflectance showed typical red edge shifts. Secondly, the testing model of partial least square(PLS) established by the entire datasets to validate the predictive performance at each stage yielded poor LCC estimation accuracy. The spectral wavelengths of red edge(RE) and blue edge(BE) shifts and the poor estimation capability motivated us to further explore the growth stage effects by establishing LCC models at respective growth periods.Finally, competitive adaptive reweighted sampling PLS(CARS-PLS), decision tree(DT) and random forest(RF) were used to select sensitive bands and establish LCC models at specific stages. Bayes optimisation was used to tune the hyperparameters of DT and RF regression. The modelling results indicated that CARS-PLS and DT did not extract specific wavelengths that could decrease the influences of growth stage effects. From the RF out-of-bag(OOB) evaluation, the sensitive wavelengths displayed consistent spectral shifts from BE to GP and from RE to RV from tillering to heading stages. Compared with CARS-PLS and DT,results of RF modelling yielded an estimation accuracy with deviation to performance(RPD) of 2.11, 2.02,3.21 and 3.02, which can accommodate the growth stage effects. Thus, this study explores spectral response on growth stage effects and provides models for chlorophyll content estimation to satisfy the requirement of high-throughput phenotyping. 展开更多
关键词 Wheat chlorophyll content Growth stage effects Sensitive wavelengths Spectral response Random forest
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Effect of Cycloheximide on the Adaptive Response Induced by Low Dose Radiation 被引量:4
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作者 CAI Lu AND LIu SHUZHENGDepartment of Radiation Biology, Institute of Radiation Medicine, Norman Bethune University of Medical Sciences, Changchun 130021, China Corresponding author 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1992年第1期46-52,共7页
Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhi... Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhibited by cycloheximide, a protein synthesis inhibitor for successive 2 h period ranging from 0.5h before to 4h after the low dose exposure, indicating that the adaptive response was directly related with the protein synthesis. 展开更多
关键词 In effect of Cycloheximide on the Adaptive response Induced by Low Dose Radiation
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Electric field distribution and effective nonlinear AC and DC responses of graded cylindrical composites 被引量:1
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作者 丁霞 贾艳霞 魏恩泊 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期569-576,共8页
The perturbation method is used to study the localization of electric field distribution and the effective nonlinear response of graded composites under an external alternating-current(AC) and direct-current(DC) e... The perturbation method is used to study the localization of electric field distribution and the effective nonlinear response of graded composites under an external alternating-current(AC) and direct-current(DC) electric field E app = E 0(1 + sin ωt).The dielectric profile of the cylindrical inclusions is modeled by function ε i(r) = C k r k(r ≤ a),where r is the radius of the cylindrical inclusion,and C k,k,a are parameters.In the dilute limit,the local potentials and the effective nonlinear responses at all harmonics are derived.Meanwhile,the general effective nonlinear responses are also derived and compared with the effective nonlinear responses at harmonics under the AC and DC external field.It is found that the effective nonlinear AC and DC responses at harmonics can be calculated by those of the general effective nonlinear of the graded composites under the external DC electric field.Moreover,the obtained local electrical fields show that the electrical field distribution in the cylindrical inclusions is controllable,and the maximum of the electric field inside the cylinder is at its center. 展开更多
关键词 graded composite effective nonlinear alternating-current and direct-current response local electric field distribution
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Effective Dielectric Response of Composites with Graded Material 被引量:1
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作者 YANGZi-Dong WEIEn-Bo SONGJin-Bao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期957-960,共4页
The effective dielectric response of linear composites containing graded material is investigated under an applied electric field E_0.For the cylindrical inclusion with gradient dielectric function,ει(r)=b+cr,random... The effective dielectric response of linear composites containing graded material is investigated under an applied electric field E_0.For the cylindrical inclusion with gradient dielectric function,ει(r)=b+cr,randomly embedded in a host with dielectric constant εm,we have obtained the exact solution of local electric potential of the composite media regions,which obeys a linear constitutive relation D=εE,using hypergeometric function.In dilute limit,we have derived the effective dielectric response of the linear composite media.Furthermore,for larger volume fraction,the formulas of effective dielectric response of the graded composite media are given. 展开更多
关键词 effective dielectric response graded composite effective medium approximation
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