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Responses of steppe birds to habitat fragmentation:Insights from niche specialization and functional traits
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作者 Zheng Han Xi Yang +3 位作者 Lishi Zhang Piotr Tryjanowski Frédéric Jiguet Haitao Wang 《Avian Research》 2025年第3期353-361,共9页
Habitat fragmentation poses a significant threat to bird communities, especially those in open and semi-open ecosystems such as steppes. This study investigates how steppe birds adapt to and utilize fragmented habitat... Habitat fragmentation poses a significant threat to bird communities, especially those in open and semi-open ecosystems such as steppes. This study investigates how steppe birds adapt to and utilize fragmented habitats by combining niche modeling with ecological trait analysis. We conducted standardized point surveys to examine the habitat preferences of 32 bird species in Inner Mongolia, China, and quantified their habitat niche parameters using the Outlying Mean Index (OMI). Our results reveal distinct habitat preferences among species, with some thriving in intact environments while others are better adapted to fragmented areas. Grassland species showed high specialization along the fragmentation gradient, while others exhibited adaptability to varying levels of fragmentation. Using a Generalized Additive Model (GAM), we identified three key traits influencing habitat occupancy: hand-wing index, body mass, and range size. Specifically, species with medium hand-wing indices, moderate body mass, and larger range sizes were more likely to occupy heavily fragmented habitats. These findings provide empirical evidence on how habitat fragmentation affects bird species in steppe ecosystems. The study highlights the importance of functional traits in understanding avian responses to habitat fragmentation and offers a foundation for developing effective conservation strategies to preserve biodiversity in fragmented landscapes. 展开更多
关键词 CONSERVATION functional traits Habitat fragmentation Niche position response Steppe birds
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Early improvement to electroacupuncture at week 3 predicts ultimate response in patients with chronic severe functional constipation
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作者 Zhi-yi Xiong Shi-yan Yan +1 位作者 Si-xing Liu Zhi-shun Liu 《Journal of Integrative Medicine》 2025年第3期274-281,共8页
Objective:To investigate whether the presence or absence of improvement in chronic severe functional constipation(CSFC)at the early stage of treatment with electroacupuncture predicts subsequent response or non-respon... Objective:To investigate whether the presence or absence of improvement in chronic severe functional constipation(CSFC)at the early stage of treatment with electroacupuncture predicts subsequent response or non-response,and to determine the optimal treatment duration for assessing subsequent responses to electroacupuncture.Methods:This is a post hoc analysis using data pooled from two large-scale randomized controlled trials.Patients with CSFC were recruited,and those in the electroacupuncture groups were included in the present study.Early improvement was defined as a weekly increase of≥1 complete spontaneous bowel movement(CSBM)compared to baseline.Three treatment response criteria were evaluated:≥3CSBMs per week,overall CSBM response,and sustained CSBM response.Predictive statistics,including sensitivity,specificity,positive predictive value,and negative predictive value,were calculated at weeks1–4.Receiver operating characteristic curves and accuracy rates were used to determine the optimal timepoint for differentiation between responders and non-responders.Results:Cases from a total of 813 participants who received electroacupuncture were analyzed.The proportion of improvers was 40.34%by week 1,increasing to 52.52%by week 4.After 8 weeks of treatment,the response rates were 30.14%,25.83%and 25.58%according to the three aforementioned criteria,respectively.Early improvement was a strong predictor of treatment response,with week 3 demonstrating the highest predictive accuracy.Conclusion:Early improvement with electroacupuncture,especially at week 3,can predict subsequent outcomes.Our findings suggest that acupuncturists may identify non-responders who might require adjustments to therapeutic strategies early in treatment. 展开更多
关键词 Chronic severe functional constipation ELECTROACUPUNCTURE Early improvement PREDICTION Treatment response
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Stability Analysis of an Epidemic Predator-Prey Model with Prey Dispersal and Holling Type-Ⅱ Functional Response
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作者 Lingshu WANG Mei ZHANG Ya-nan ZHANG 《Journal of Mathematical Research with Applications》 2025年第2期179-194,共16页
This paper examines an epidemic predator-prey model with prey dispersal and Holling type-II functional response. In this model, it is assumed that the predator population suffers a transmissible disease. By analyzing ... This paper examines an epidemic predator-prey model with prey dispersal and Holling type-II functional response. In this model, it is assumed that the predator population suffers a transmissible disease. By analyzing the corresponding characteristic equations, the local stability of each of feasible equilibria and the existence of Hopf bifurcations at the coexistence equilibrium is addressed. Using Lyapunov functionals and LaSalle's invariance principle, we obtained the sufficient conditions for the global stability of the trivial equilibrium, the predator-extinction equilibrium, the disease-free equilibrium and the coexistence equilibrium, respectively. The paper also includes numerical simulations to illustrate the analytical results. 展开更多
关键词 predator-prey model dispersal Holling type-II functional response Hopf bifurcation stability
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The effect of dispersal on a predator-prey model with Holling type-Ⅱ functional response
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作者 WANG Ling-shu ZHANG Mei +1 位作者 ZHANG Ya-nan WANG Yan 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期602-616,共15页
A predator-prey model with prey dispersal and Holling type-Ⅱ functional response is investigated.In this model,the time delay due to the gestation of the predator and stagestructure for the predator are considered.By... A predator-prey model with prey dispersal and Holling type-Ⅱ functional response is investigated.In this model,the time delay due to the gestation of the predator and stagestructure for the predator are considered.By analyzing the corresponding characteristic equations,the local stability of each of the nonnegative equilibria is discussed.The existence of Hopf bifurcations at the positive equilibrium is established.By using Lyapunov functionals and LaSalle’s invariance principle,sufficient conditions are obtained for the global stability of the positive equilibrium,the nonnegative boundary equilibrium and the trivial equilibrium of the model,respectively.Numerical simulations are carried out to illustrate the main results. 展开更多
关键词 predator-prey model dispersal Holling type-Ⅱfunctional response time delay STAGE-STRUCTURE STABILITY
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Visual electrophysiological assessment of children with poor response to treatment for functional amblyopia
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作者 Dong-Qing Yuan Wei-Wei Zhang +1 位作者 Liu-Wei Gu Qing-Huai Liu 《International Journal of Ophthalmology(English edition)》 2025年第2期315-322,共8页
AIM:To assess the visual electrophysiological outcomes in children with functional amblyopia who exhibited poor response to conventional treatment.METHODS:Twenty-one children with functional amblyopia,aged 5.7±2.... AIM:To assess the visual electrophysiological outcomes in children with functional amblyopia who exhibited poor response to conventional treatment.METHODS:Twenty-one children with functional amblyopia,aged 5.7±2.1y(range:4-10y),underwent comprehensive ophthalmic and refractive evaluations.Spectral domain-optical coherence tomography(SD-OCT)and multifocal electroretinography(mfERG)were conducted to analyze the macular retinal thickness and the first-order response P1 ring of the mfERG in the amblyopic eye(AE)compared to the fellow good eye(GE).RESULTS:Initially,visual acuity in the AE ranged from 20/800 to 20/40,while the GE exhibited a range of 20/25 to 20/20(P<0.01).After 6mo of treatment,17 patients demonstrated improved visual acuity in the AE to 20/50 or better,while 4 children showed no improvement.SD-OCT revealed comparable macular and optic disc structures between the AE and GE.Prior to treatment,the mfERG P1 ring amplitude was significantly reduced in the AE compared to GE(P<0.05).The AE/GE ratio of P1 ring amplitude showed significant improvement post-treatment.However,a smaller AE/GE ratio before treatment was associated with poorer improvement post-treatment.CONCLUSION:In the management of functional amblyopia,a thorough assessment of amblyopic eye examinations is crucial.Approximately 20%of amblyopic eyes may not achieve significant improvement in visual acuity,despite the absence of detectable organic retinal abnormalities.mfERG may reveal underlying abnormalities.Integrating mfERG into initial assessments or treatment follow-ups can aid in identifying potential hidden retinal defects and predicting the prognosis of the amblyopic eye. 展开更多
关键词 functional amblyopia poor response optical coherence tomography multifocal electroretinography retinal defects
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A Novel Functional Method of Protector Screening for Zebrafish Lateral Line Hair Cells via the Acoustic Escape Response
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作者 Ling Zheng Qiaosen Shen +8 位作者 Tong Zhao Qingsong Liu Zihao Huang Feng Zhao Mengqian Zhang Yongdong Song Daogong Zhang Dong Liu Fangyi Chen 《Neuroscience Bulletin》 2025年第9期1537-1552,共16页
Zebrafish larvae are useful for identifying chemicals against lateral line(LL)hair cell(HC)damage and this type of chemical screen mainly focuses on searching for protectors against cell death.To expand the candidate ... Zebrafish larvae are useful for identifying chemicals against lateral line(LL)hair cell(HC)damage and this type of chemical screen mainly focuses on searching for protectors against cell death.To expand the candidate pool of HC protectors,a self-built acoustic escape response(AER)-detecting system was developed to apply both low-frequency near-field sound transmission and AER image acquisition/processing modules.The device quickly confirmed the changed LL HC functions caused by most known ototoxins,protectors,and neural transmission modifiers,or knockdown of LL HC-expressing genes.With ten devices wired in tandem,five‘hit’chemicals were identified from 124 cyclin-dependent kinase inhibitors to partially restore cisplatin-damaged AER in less than a day.AS2863619,ribociclib,and SU9516 among the hits,protected the HCs in the mouse cochlea.Therefore,using free-swimming larval zebrafish,the self-made AER-detecting device can efficiently identify compounds that are protective against HC damage,including cell death and loss-of-function. 展开更多
关键词 Acoustic escape response Zebrafish Lateral line Hair cell Low-frequency sound functional screening
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Effects of Ozone Exposure on Cardiopulmonary Function and Adaptive Responses in Han and Tibetan Children during Physical Activity at High Altitudes
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作者 Mengyao Bian Ling Qi +2 位作者 Qian Guo Yuchen Zhao Xiaoli Duan 《Biomedical and Environmental Sciences》 2025年第5期633-638,共6页
The cardiopulmonary health of children may be affected by acute ozone(O3)exposure during physical activity[1];however,its effects in high-altitude regions such as the Xizang Plateau remain uncertain.In high-altitude a... The cardiopulmonary health of children may be affected by acute ozone(O3)exposure during physical activity[1];however,its effects in high-altitude regions such as the Xizang Plateau remain uncertain.In high-altitude areas,lower oxygen levels may cause children to experience shortness of breath or require increased respiratory effort during vigorous activities such as running.This could lead to increased pollutant inhalation,potentially elevating the burden on the cardiovascular system and triggering adverse reactions such as increased heart rate and elevated blood pressure.Furthermore,differences in physiological adaptation between Han children who have migrated to Xizang and Tibetan children who are native to the region may contribute to different reactions to environmental exposure[2]. 展开更多
关键词 cardiopulmonary health cardiopulmonary function cardiovascular system shortness breath pollutant inhalationpotentially Tibetan children adaptive responses ozone exposure
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Enhanced Flexoelectric Response from Functionally Gradient Electrets Undergoing Crumpling Deformation
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作者 Jianhua Ma Jinrui Xu +1 位作者 Jun Li Binglei Wang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2024年第4期541-554,共14页
Non-uniform deformation of the dielectric subjected to external forces can induce the flexoelectric effect, a phenomenon that couples electrical polarization to strain gradients. However, limited by the size effects, ... Non-uniform deformation of the dielectric subjected to external forces can induce the flexoelectric effect, a phenomenon that couples electrical polarization to strain gradients. However, limited by the size effects, flexoelectricity is not significant at the macroscale and only becomes catchable at the microscale and nanoscale. In recent work, we obtained a considerable flexoelectric-like response by crumpling the dielectric embedded with charges, i.e., the electret, which significantly improved the flexoelectric effect at the macroscale. In this work, we further optimize the macroscopic performance of the flexoelectric response by applying gradient treatment to the electret films. Specifically, we analytically derive the electromechanical coupling of crumpled electret films with gradients of different thicknesses, charge densities, and Young’s moduli as key design variables. It is shown that the gradient-oriented electret film can be tuned to nearly five times that of a uniform electret film. 展开更多
关键词 functionally gradient electret Size effects Crumpling Flexoelectric-like response
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Bifurcation and Turing Pattern Formation in a Diffusion Modified Leslie-Gower Predator-Prey Model with Crowley-Martin Functional Response
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作者 Dong Wang Yani Ma 《Journal of Applied Mathematics and Physics》 2024年第6期2190-2211,共22页
In this paper, we study a modified Leslie-Gower predator-prey model with Smith growth subject to homogeneous Neumann boundary condition, in which the functional response is the Crowley-Martin functional response term.... In this paper, we study a modified Leslie-Gower predator-prey model with Smith growth subject to homogeneous Neumann boundary condition, in which the functional response is the Crowley-Martin functional response term. Firstly, for ODE model, the local stability of equilibrium point is given. And by using bifurcation theory and selecting suitable bifurcation parameters, we find many kinds of bifurcation phenomena, including Transcritical bifurcation and Hopf bifurcation. For the reaction-diffusion model, we find that Turing instability occurs. Besides, it is proved that Hopf bifurcation exists in the model. Finally, numerical simulations are presented to verify and illustrate the theoretical results. 展开更多
关键词 Modified Leslie-Gower Model Crowley-Martin function response Hopf Bifurcation Transcritical Bifurcation Turing Instability
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Establishment of the“4 stages-6 sequences”repair method and quantification analysis on post-earthquake functional recovery of railway station
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作者 Song Jiayu Gao Haiwang +1 位作者 Pan Yi Jiang Junpeng 《Earthquake Engineering and Engineering Vibration》 2025年第3期827-842,共16页
Quantifying the post-earthquake functional recovery of railway stations presents significant challenges.This paper first establishes a post-earthquake function calculation method for railway stations,encompassing the ... Quantifying the post-earthquake functional recovery of railway stations presents significant challenges.This paper first establishes a post-earthquake function calculation method for railway stations,encompassing the establishment of relationships between the station’s function and the damage state,function loss,and failure probability of components and professional equipment in each layer.Also,the“4 stages-6 sequences”post-earthquake repair method is present,taking into account the functional and structural characteristics of railway stations.Additionally,a novel piecewise function for the post-earthquake functional dynamic recovery of railway stations is developed.A case study is conducted on a typical railway station to demonstrate the analysis procedure.Results indicate that under fortification,rare,and extremely rare earthquake scenarios,the interlayer drift ratio(IDR)of the railway station were 1/276,1/143,and 1/52,respectively,and corresponding peak floor acceleration(PFA)were 6.31 m/s^(2),7.82 m/s^(2),and 8.57 m/s^(2),respectively.The post-earthquake function of the railway station was 93.21%,82.33%,and 64.16%of its initial function.The repair times were 6.66 days,18.65 days,and 37.42 days.The displacement-sensitive,non-structural components were identified as the most vulnerable to damage.And the first repair stage(R_(1))which was mainly used to repair structural components and non-structural transport components,accounted for the highest proportion of total repair time. 展开更多
关键词 railway stations seismic response post-earthquake function functional recovery model repair method
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Applying the Liouville–Lanczos method of time-dependent density-functional theory to warm dense matter
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作者 Zhandos A.Moldabekov Sebastian Schwalbe +3 位作者 Thomas Gawne Thomas R.Preston Jan Vorberger Tobias Dornheim 《Matter and Radiation at Extremes》 2025年第4期44-57,共14页
Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instr... Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instrument function,is measured in X-ray Thom-son scattering(XRTS)experiments,which allow the study of electronic structure properties at the microscopic level.Among the various ab initio methods,linear-response time-dependent density-functional theory(LR-TDDFT)is a key framework for simulating the DSF.The standard approach in LR-TDDFT for computing the DSF relies on the orbital representation.A significant drawback of this method is the unfavorable scaling of the number of required empty bands as the wavenumber increases,making LR-TDDFT impractical for modeling XRTS measurements over large energy scales,such as in backward scattering geometry.In this work,we consider and test an alternative approach to LR-TDDFT that employs the Liouville–Lanczos(LL)method for simulating the DSF of WDM.This approach does not require empty states and allows the DSF at large momentum transfer values and over a broad frequency range to be accessed.We compare the results obtained from the LL method with those from the solution of Dyson’s equation using the standard LR-TDDFT within the projector augmented-wave formalism for isochorically heated aluminum and warm dense hydrogen.Additionally,we utilize exact path integral Monte Carlo results for the imaginary-time density-density correlation function(ITCF)of warm dense hydrogen to rigorously benchmark the LL approach.We discuss the application of the LL method for calculating DSFs and ITCFs at different wavenumbers,the effects of pseudopotentials,and the role of Lorentzian smearing.The successful validation of the LL method under WDM conditions makes it a valuable addition to the ab initio simulation landscape,supporting experimental efforts and advancing WDM theory. 展开更多
关键词 ab initio dynamic structure factors dsf Liouville Lanczos method simulating ds ab initio methodslinear response warm dense matter time dependent density functional theory density response properties
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An isogeometric approach for vibration characteristics analysis of functionally graded triply periodic minimal sandwich curved-doubly shell integrated with magneto-electro surface layers subjected to lowvelocity impact load
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作者 Le Hoai Pham Hoang Tu +1 位作者 Van Ke Tran Nguyen Thi Hue 《Defence Technology(防务技术)》 2025年第8期101-125,共25页
In this paper,the isogeometric analysis(IGA)method is employed to analyze the oscillation characteristics of functionally graded triply periodic minimal surface(FG-TPMS)curved-doubly shells integrated with magneto-ele... In this paper,the isogeometric analysis(IGA)method is employed to analyze the oscillation characteristics of functionally graded triply periodic minimal surface(FG-TPMS)curved-doubly shells integrated with magneto-electric surface layers(referred to as"FG-TPMS-MEE curved-doubly shells")subjected to low-velocity impact loads.This study presents low-velocity impact load model based on a single springmass(S-M)approach.The FG-TPMS-MEE curved-doubly shells are covered with two magneto-electric surface layers,while the core layer consists of three types:I-graph and Wrapped Package-graph(IWP),Gyroid(G),and Primitive(P),with various graded functions.These types are notable for their exceptional stiffness-to-weight ratios,enabling a wide range of potential applications.The Maxwell equations and electromagnetic boundary conditions are applied to compute the change in electric potentials and magnetic potentials.The equilibrium equations of the shell are derived from a refined higher-order shear deformation theory(HSDT),and the transient responses of the FG-TPMS-MEE curveddoubly shells are subsequently determined using Newmark's direct integration method.These results have applications in structural vibration control and the analysis of structures subjected to impact or explosive loads.Furthermore,this study provides a theoretical prediction of the low-velocity impact load and magneto-electric-elastic effects on the free vibration and transient response of FG-TPMS-MEE curved-doubly shells. 展开更多
关键词 IGA approach Free vibration and transient response Magneto-electro-elastic curved-doubly shell Low-velocity impact load functionally graded triply periodic minimal
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Impact of minimally invasive surgery on immune function and stress response in gastric cancer patients 被引量:4
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作者 Rong-Hua Zhu Peng-Cheng Li +1 位作者 Jie Zhang Hua-Hua Song 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2484-2493,共10页
BACKGROUND Gastric cancer remains a leading cause of cancer-related mortality globally.Traditional open surgery for gastric cancer is often associated with significant morbidity and prolonged recovery.AIM To evaluate ... BACKGROUND Gastric cancer remains a leading cause of cancer-related mortality globally.Traditional open surgery for gastric cancer is often associated with significant morbidity and prolonged recovery.AIM To evaluate the effectiveness of laparoscopic minimally invasive surgery as an alternative to traditional open surgery for gastric cancer,focusing on its potential to reduce trauma,accelerate recovery,and achieve comparable oncological out-comes.METHODS This study retrospectively analyzed 203 patients with gastric cancer who underwent surgery at the Shanghai Health Medical College Affiliated Chongming Hospital from January 2020 to December 2023.The patients were divided into two groups:Minimally invasive surgery group(n=102),who underwent laparoscopic gastrectomy,and open surgery group(n=101),who underwent traditional open gastrectomy.We compared surgical indicators(surgical incision size,intraop-erative blood loss,surgical duration,and number of lymph nodes dissected),recovery parameters(time to first flatus,time to start eating,time to ambulation,and length of hospital stay),immune function(levels of IgA,IgG,and IgM),intestinal barrier function(levels of D-lactic acid and diamine oxidase),and stress response(levels of C-reactive protein,interleukin-6,and procalcitonin).RESULTS The minimally invasive surgery group demonstrated significantly better outcomes in terms of surgical indicators,including smaller incisions,less blood loss,shorter surgery time,and more lymph nodes dissected(P<0.05 for all).Recovery was also faster in the minimally invasive surgery group,with earlier return of bowel function,earlier initiation of diet,quicker mobilization,and shorter hospital stays(P<0.05 for all).Furthermore,patients in the minimally invasive surgery group had better preserved immune function,superior intestinal barrier function,and a less pronounced stress response postoperatively(P<0.05 for all).CONCLUSION Laparoscopic minimally invasive surgery for gastric cancer not only provides superior surgical indicators and faster recovery but also offers advantages in preserving immune function,protecting intestinal barrier function,and mitigating the stress response compared to traditional open surgery.These findings support the broader adoption of laparoscopic techniques in the management of gastric cancer. 展开更多
关键词 Gastric cancer Laparoscopic surgery Minimally invasive surgery Immune function Intestinal barrier Stress response
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DiriNet:An Estimation Network for Spectral Response Function and Point Spread Function 被引量:1
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作者 Ting Hu Siyuan Cheng Chang Liu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第4期287-297,共11页
Hyper-and multi-spectral image fusion is an important technology to produce hyper-spectral and hyper-resolution images,which always depends on the spectral response function andthe point spread function.However,few wo... Hyper-and multi-spectral image fusion is an important technology to produce hyper-spectral and hyper-resolution images,which always depends on the spectral response function andthe point spread function.However,few works have been payed on the estimation of the two degra-dation functions.To learn the two functions from image pairs to be fused,we propose a Dirichletnetwork,where both functions are properly constrained.Specifically,the spatial response function isconstrained with positivity,while the Dirichlet distribution along with a total variation is imposedon the point spread function.To the best of our knowledge,the neural network and the Dirichlet regularization are exclusively investigated,for the first time,to estimate the degradation functions.Both image degradation and fusion experiments demonstrate the effectiveness and superiority of theproposed Dirichlet network. 展开更多
关键词 Dirichlet network point spread function spectral response function hyper-spectralimage multi-spectral image
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Elastoplastic response of functionally graded cemented carbides due to thermal loading
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作者 黄自谦 李传新 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期463-466,共4页
Finite dement formulations are used to simulate the evolution of the elastoplastic response of functionally graded cemented carbides (FGCC) due to thermal loading. The geometry of specimens is an axisymmetric solid ... Finite dement formulations are used to simulate the evolution of the elastoplastic response of functionally graded cemented carbides (FGCC) due to thermal loading. The geometry of specimens is an axisymmetric solid cylinder with a two-dimensional gradient. The elastoplastic constitutive relationship is developed by constraint factors. Numerical results show that compressive stresses occur in the surface zone and tensile stresses in the cobalt rich zone when the temperature drops from the initial stress-free temperature of 800 to 0℃. The maximum value of the surface compressive stress is 254 MPa and the maximum value of the tensile stress is 252 MPa in the cobalt rich zones. When the cobalt concentration difference in the specimens is equal to or greater than 0.3, there is pronounced plastic flow in cobalt rich zone. When the temperature heats up from 0 to 800 ℃, the total plastic strain reaches 0.001 4. Plastic flow has a significant effect on the reduction of thermal stress concentration. 展开更多
关键词 functionally graded cemented carbides finite element method constraint factors elastoplastic response
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Mechanism of Functional Responses to Loading of Carbon Fiber Reinforced Cement-based Composites 被引量:6
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作者 JIANG Cuixiang LI Zhuoqiu +1 位作者 SONG Xianhui LU Yong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第4期571-573,共3页
Single fiber pull-out testing was conducted to study the origin of the functional responses to loading of carbon fiber reinforced cement-based composites. The variation of electrical resistance with the bonding force ... Single fiber pull-out testing was conducted to study the origin of the functional responses to loading of carbon fiber reinforced cement-based composites. The variation of electrical resistance with the bonding force on the fiber-matrix interface was measured. Single fiber electromechanical testing was also conducted by measuring the electrical resistance under static tension. Comparison of the results shows that the resistance increasing during single fiber pull-out is mainly due to the changes at the interface. The conduction mechanism of the composite can be explained by the tunneling model. The interfacial stress causes the deformation of interfacial structure and the interfacial debonding, which have influences on the tunneling effect and result in the change of resistance. 展开更多
关键词 carbon fiber functional response tunneling effect single pull-out CEMENT
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Effects of Temperature on Functional Response of Anagrus nilaparvatae Pang et Wang (Hymenoptera:Mymaridae) on the Eggs of Whitebacked Planthopper,Sogatella furcifera Horvth and Brown Planthopper,Nilaparvata lugens Stl 被引量:4
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作者 MA Ming-yong PENG Zhao-pu HE Yuan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第8期1313-1320,共8页
Understanding the temperature affecting parasitic efficiency is critical to succeed in utilizing parasitoid as natural enemy in pest management. Laboratory studies were carried out to determine the effects of temperat... Understanding the temperature affecting parasitic efficiency is critical to succeed in utilizing parasitoid as natural enemy in pest management. Laboratory studies were carried out to determine the effects of temperature on parasitoid preference of female Anagrus nilaparvatae Pang et Wang (Hymenoptera:Mymaridae) to the eggs of whitebacked planthopper (WBPH), Sogatella furcifera Horváth and brown planthopper (BPH), Nilaparvata lugens Stl to build a composite model describing changes in parasitic response along a temperature gradient (18, 22, 26, 30, 34°C). The results showed that attack responses of A. nilaparvatae on WBPH and BPH were the best described by a Type II functional response. The two parameters, attack rates (a) and handling times (Th), of A. nilaparvatae to both eggs were influenced by the temperature. The maximum attack rates to WBPH (1.235) and BPH (1.049) were at 26 and 34°C, respectively, and the shortest handling times to WBPH (0.063) and BPH (0.057) were at 30 and 26°C, respectively. However, the optimal temperature for parasitic efficiency of A. nilaparvatae to WBPH and BPH eggs was both at 26°C, which showed that the present microclimate temperature of the habitat in the paddyfield was beneficial to A. nilaparvatae and indicated that parasitic efficiency of A. nilaparvatae would be impaired by global warming. 展开更多
关键词 functional response TEMPERATURE Anagrus nilaparvatae whitebacked planthopper brown planthopper
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EXISTENCE OF POSITIVE SOLUTION FOR A TWO-PATCHES COMPETITION SYSTEM WITH DIFFUSION AND TIME DELAY AND FUNCTIONAL RESPONSE 被引量:12
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作者 Li Biwen Zeng Xianwu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期1-8,共8页
By using the continuation theorem of coincidence theory,the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional response x_(1)(t)=x_(1)(t)a_(1)(t... By using the continuation theorem of coincidence theory,the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional response x_(1)(t)=x_(1)(t)a_(1)(t)-b_(1)(t)x_(1)(t)-c_(1)(t)y(t)1+m(t)x_(1)(t)+D_(1)(t)[x_(2)(t)-x_(1)(t)],x_(2)(t)=x_(2)(t)a_(2)(t)-b_(2)(t)x_(2)(t)-c_(2)(t)∫^(0)_(-τ)k(s)x_(2)(t+s)d s+D_(2)(t)[x_(1)(t)-x_(2)(t)],y′(t)=y(t)a_(3)(t)-b_(3)(t)y(t)-c_(3)(t)x_(1)(t)1+m(t)x_(1)(t)is established,where a i(t),b_(i)(t),c_(i)(t)(i=1,2,3),m(t)and D_(i)(t)(i=1,2)are all positive periodic continuous functions with period w>0,τis a nonnegative constant and k(s)is a continuous nonnegative function on[-τ,0]. 展开更多
关键词 periodic solutions competition diffusive system functional response continuation theorem of coincidence degree topological degree
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The Dynamical Behavior of a Certain Predator-Prey System with Holling Type II Functional Response 被引量:6
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作者 Shuangte Wang Hengguo Yu +1 位作者 Chuanjun Dai Min Zhao 《Journal of Applied Mathematics and Physics》 2020年第3期527-547,共21页
In this paper we analytically and numerically consider the dynamical behavior of a certain predator-prey system with Holling type II functional response, including local and global stability analysis, existence of lim... In this paper we analytically and numerically consider the dynamical behavior of a certain predator-prey system with Holling type II functional response, including local and global stability analysis, existence of limit cycles, transcritical and Hopf bifurcations. Mathematical theory derivation mainly focuses on the existence and stability of equilibrium point as well as threshold conditions for transcritical and Hopf bifurcation, which can in turn provide a theoretical support for numerical simulation. Numerical analysis indicates that theoretical derivation results are correct and feasible. In addition, it is successful to show that the dynamical behavior of this predator-prey system mainly depends on some critical parameters and mathematical relationships. All these results are expected to be meaningful in the study of the dynamic complexity of predatory ecosystem. 展开更多
关键词 PREDATOR-PREY System HOLLING Type II functional response Global Stability BIFURCATION Analysis
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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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