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DiriNet:An Estimation Network for Spectral Response Function and Point Spread Function
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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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Impact of minimally invasive surgery on immune function and stress response in gastric cancer patients
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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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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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Inflammation: Complexity and significance of cellular and molecular responses 被引量:1
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作者 Serdar Ozdemir 《Journal of Acute Disease》 2024年第1期3-7,共5页
Inflammation is a multifaceted cellular and molecular response triggered by injury,infection,or various pathological conditions.Serving as a protective defense mechanism,the inflammatory response involves clinical sig... Inflammation is a multifaceted cellular and molecular response triggered by injury,infection,or various pathological conditions.Serving as a protective defense mechanism,the inflammatory response involves clinical signs like redness,swelling,pain,and increased body temperature.Immune cells,notably neutrophils and macrophages,play key roles in orchestrating this response.The delicate balance between proinflammatory and anti-inflammatory mediators,including cytokines and chemokines,regulates the inflammatory cascade.While acute inflammation is crucial for tissue repair,chronic inflammation may indicate an imbalance,contributing to conditions like autoimmune diseases.Understanding these mechanisms is vital for developing therapeutic strategies and managing chronic diseases. 展开更多
关键词 INFLAMMATION C-reactive protein PLATELETS SCUBE1 ADRENOMEDULLIN CALPROTECTIN Pentraxin-3 Immune response Acute phase response Vascular function
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Improvement of inflammatory response and gastrointestinal function in perioperative of cholelithiasis by Modified Xiao-Cheng-Qi decoction 被引量:2
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作者 Bao-Fang Sun Fan Zhang +4 位作者 Qiang-Pu Chen Qiang Wei Wen-Tao Zhu Hai-Bin Ji Xing-Yuan Zhang 《World Journal of Clinical Cases》 SCIE 2023年第4期830-843,共14页
BACKGROUND In the perioperative period of biliary surgery,various factors can induce the release of a large number of inflammatory factors,leading to an imbalance in proinflammatory and anti-inflammatory responses and... BACKGROUND In the perioperative period of biliary surgery,various factors can induce the release of a large number of inflammatory factors,leading to an imbalance in proinflammatory and anti-inflammatory responses and resulting in gastrointestinal(GI)dysfunction.Enhanced Recovery After Surgery protocols in biliary surgery have been shown to reduce the stress response and accelerate postoperative recovery.It is crucial to reduce the inflammatory response and promote the recovery of GI function after biliary surgery,both of which are the basis and key for perioperative care and postoperative recovery.AIM To better understand the effects of Modified Xiao-Cheng-Qi decoction(MXD)on inflammatory response and GI function in the perioperative management of cholelithiasis and their correlation.METHODS This was a prospective randomized placebo-controlled trial,in which 162 patients who received biliary tract surgery were randomly assigned to three groups:MXD group,XD group,and placebo-control group.The observed parameters included frequency of bowel sounds,time of first flatus and defecation,time of diet,and amount of activity after surgery.The serum levels of C-reactive protein(CRP),interleukin(IL)-6,IL-10,serum amyloid A protein(SAA),and substance P were measured by the enzyme-linked immunosorbent assay.Then,the spearman correlation coefficient was used to analyze the relationship between the indicators of GI function and inflammation.RESULTS Compared to the placebo-control,improvements in GI function were observed in the MXD groups including reduced incidence of nausea,vomiting,and bloating;and earlier first exhaust time,first defecation time,and feeding time after surgery(P<0.05).On the 1st and 2nd d after surgery,IL-6,CRP and SAA levels in MXD group were lower than that in placebo control,but substance P level was higher,compared to the control(P<0.05).Functional diarrhea occurred in both MXD and XD groups without any other adverse effects,toxic reactions,and allergic reactions.Diarrhea was relieved after the discontinuation of the investigational remedies.Bowel sounds at 12 h after surgery,the occurring time of the first flatus,first defecation,postoperative liquid diet and semiliquid diet were significantly correlated with levels of IL-6,CRP,SAA and substance P on second day after surgery(P<0.05).CONCLUSION Treatment with MXD can relieve inflammatory response and improve GI function after surgery.Moreover,there are significant correlations between them.Furthermore,it does not cause serious adverse reactions. 展开更多
关键词 Modified Xiao-cheng-qi Decoction CHOLELITHIASIS Inflammatory response Gastrointestinal function Enhanced Recovery After Surgery PERIOPERATIVE
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Improvement of a temperature response function for divertor heat flux monitoring in fusion devices
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作者 Xuan Nhat Son BUI Hiroto MATSUURA Yousuke NAKASHIMA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第3期217-221,共5页
Temperature response functions have been developed to investigate sensor design and divertor heat flux estimation in magnetically confined plasmas. The time-dependent heat flux can be derived by fitting the response f... Temperature response functions have been developed to investigate sensor design and divertor heat flux estimation in magnetically confined plasmas. The time-dependent heat flux can be derived by fitting the response function to experimental thermocouple(TC) data. Because the TC signals have a time delay to transit events such as discharge start or confinement transition, the time delay is taken into account in a temperature response function. Such a function accurately describes the signal from each TC channel with time delay in a sensor test using a neutral beam injection. Measurement for commercial TCs shows that the time delay is caused by the finite heat capacity of TC wire and contact heat resistance between TC and target surface. 展开更多
关键词 DIVERTOR temperature response function thermocouple system primary delay
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Stability Analysis of a Self-Memory Prey-Predator Diffusion Model Based on Bazykin Functional Response
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作者 Yanzhe Han Fuqin Sun 《Journal of Applied Mathematics and Physics》 2023年第5期1391-1403,共13页
To investigate the effects of self-memory diffusion on predator-prey models, we consider a predator-prey model with Bazykin functional response of self- memory diffusion. The uniqueness, boundedness, positivity, exist... To investigate the effects of self-memory diffusion on predator-prey models, we consider a predator-prey model with Bazykin functional response of self- memory diffusion. The uniqueness, boundedness, positivity, existence and stability of equilibrium point of the model are studied. In this paper, the uniqueness of the solution is discussed under the non-negative initial function and Neumann boundary conditions satisfying a specific space. The boundness of the solution is proved by the comparison principle of parabolic equations, and the positivity of the solution is proved by the strong maximum principle of parabolic equations. Hurwitz criterion and Lyapunov function construction are used to analyze the local stability and global stability of feasible equilibrium points. The results show that the system solution is unique non-negative and bounded. The model is unstable at the trivial equilibrium point E0 and the boundary equilibrium point E1, and the condition of whether the positive equilibrium point E2 is stable under certain conditions is given. 展开更多
关键词 Bazykin functional response Lyapunov function BOUNDEDNESS UNIQUENESS Stability
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Dynamic Analysis of a Predator-Prey Model with Holling-II Functional Response
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作者 Jiemin Mo Wanying Li +2 位作者 Donghuan He Songbo Wang Xiaoliang Zhou 《Journal of Applied Mathematics and Physics》 2023年第10期2871-2878,共8页
A predator-prey model with linear capture term Holling-II functional response was studied by using differential equation theory. The existence and the stabilities of non-negative equilibrium points of the model were d... A predator-prey model with linear capture term Holling-II functional response was studied by using differential equation theory. The existence and the stabilities of non-negative equilibrium points of the model were discussed. The results show that under certain limited conditions, these two groups can maintain a balanced position, which provides a theoretical reference for relevant departments to make decisions on ecological protection. 展开更多
关键词 Predator-Prey Model Holling-II functional response Equilibrium Point STABILITY
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Tool Condition Monitoring Based on Nonlinear Output Frequency Response Functions and Multivariate Control Chart
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作者 Yufei Gui Ziqiang Lang +1 位作者 Zepeng Liu Hatim Laalej 《Journal of Dynamics, Monitoring and Diagnostics》 2023年第4期243-251,共9页
Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significa... Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significant damage to workpieces and reduce manufacturing costs.Recently,an innovative TCM approach based on sensor data modelling and model frequency analysis has been proposed.Different from traditional signal feature-based monitoring,the data from sensors are utilized to build a dynamic process model.Then,the nonlinear output frequency response functions,a concept which extends the linear system frequency response function to the nonlinear case,over the frequency range of the tooth passing frequency of the machining process are extracted to reveal tool health conditions.In order to extend the novel sensor data modelling and model frequency analysis to unsupervised condition monitoring of cutting tools,in the present study,a multivariate control chart is proposed for TCM based on the frequency domain properties of machining processes derived from the innovative sensor data modelling and model frequency analysis.The feature dimension is reduced by principal component analysis first.Then the moving average strategy is exploited to generate monitoring variables and overcome the effects of noises.The milling experiments of titanium alloys are conducted to verify the effectiveness of the proposed approach in detecting excessive flank wear of solid carbide end mills.The results demonstrate the advantages of the new approach over conventional TCM techniques and its potential in industrial applications. 展开更多
关键词 intelligent manufacturing multivariate control chart Nonlinear Autoregressive with eXogenous Input modelling Nonlinear Output Frequency response functions tool condition monitoring
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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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Serum response factor promotes axon regeneration following spinal cord transection injury 被引量:1
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作者 Guo-Ying Feng Nai-Li Zhang +5 位作者 Xiao-Wei Liu Ling-Xi Tong Chun-Lei Zhang Shuai Zhou Lu-Ping Zhang Fei Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期1956-1960,共5页
Studies have snown that serum response factor is beneficaial for axonar regeneration of peripheral herves.However,Its role after central nervous system injury remains unclear. In this study,we established a rat model ... Studies have snown that serum response factor is beneficaial for axonar regeneration of peripheral herves.However,Its role after central nervous system injury remains unclear. In this study,we established a rat model of T9-T10 spinal cord transection injury.We found that the expression of serum response factor in injured spinal cord gray matter neurons gradually increased with time,reached its peak on the 7^(th) day,and then gradually decreased.To investigate the role of serum response factor,we used lentivirus vecto rs to ove rexpress and silence serum response factor in spinal cord tissue.We found that overexpression of serum response factor promoted motor function recovery in rats with spinal cord injury.Qualitative observation of biotinylated dextran amine anterograde tra cing showed that ove rexpression of serum response factor increased nerve fibers in the injured spinal co rd.Additionally,transmission electron microscopy showed that axon and myelin sheath morphology was restored.Silencing serum response factor had the opposite effects of ove rexpression.These findings suggest that serum response factor plays a role in the recovery of motor function after spinal cord injury.The underlying mechanism may be related to the regulation of axonal regeneration. 展开更多
关键词 AXON growth associated protein 43 motor function myelin sheath NEURON REGENERATION serum response factor spinal cord spinal cord transection
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Tumor recurrence after pathological complete response in locally advanced gastric cancer after neoadjuvant therapy:Two case reports 被引量:2
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作者 Yu Xing Zi-Li Zhang +2 位作者 Zhi-Ying Ding Wei-Liang Song Tong Li 《World Journal of Clinical Cases》 SCIE 2023年第27期6483-6490,共8页
BACKGROUND The pathological complete response(ypCR)rate following neoadjuvant chemotherapy for advanced gastric cancer remains low and lacks a universally accepted treatment protocol.Immunotherapy has achieved breakth... BACKGROUND The pathological complete response(ypCR)rate following neoadjuvant chemotherapy for advanced gastric cancer remains low and lacks a universally accepted treatment protocol.Immunotherapy has achieved breakthrough progress.CASE SUMMARY We report two female patients with gastric cancer defined as clinical stage cT4N1-2M0.Detection of mismatch repair protein showed mismatch repair function defect,and perioperative treatment with programmed death protein 1 inhibitor combined with S-1+oxaliplatin achieved ypCR.Surprisingly,the patients underwent clinical observation after surgery but developed different degrees of metastasis at~6 mo after surgery.CONCLUSION PD-1 inhibitor combined with chemotherapy provides a more strategic choice for comprehensive perioperative treatment of gastric cancer. 展开更多
关键词 Programmed death protein 1 SOX Pathological complete response Microsatellite Instability High Mismatch repair function defect Case report
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Effect of ultrasound-guided lumbar square muscle block on stress response in patients undergoing radical gastric cancer surgery 被引量:1
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作者 Xin-Ran Wang Dan-Dan Xu +3 位作者 Meng-Jiao Guo Yi-Xin Wang Meng Zhang Dong-Xiao Zhu 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第12期2093-2100,共8页
BACKGROUND Radical surgery is a common treatment for patients with gastric cancer;however,it can lead to postoperative complications and intestinal barrier dysfunction.Ultrasound-guided quadratus lumborum block is oft... BACKGROUND Radical surgery is a common treatment for patients with gastric cancer;however,it can lead to postoperative complications and intestinal barrier dysfunction.Ultrasound-guided quadratus lumborum block is often used for postoperative analgesia,but its effects on stress response and intestinal barrier function are not well understood.AIM To investigate the effects of an ultrasound-guided quadratus lumborum block on stress response and intestinal barrier function in patients undergoing radical surgery for gastric cancer.METHODS A total of 100 patients undergoing radical surgery for gastric cancer were randomly categorized into observation and control groups.Plasma adrenaline and cortisol levels,intestinal mucosal barrier indexes,and complication rates were compared between the two groups before,during,and 1 day after surgery.RESULTS The observation group had significantly lower plasma adrenaline and cortisol levels during surgery and at 1 day postoperatively than that of the control group(P<0.05).Additionally,intestinal barrier indexes(endotoxin and D-dimer)at 1 day postoperatively were significantly lower in the observation group than in the control group(P<0.05).CONCLUSION Ultrasound-guided quadratus lumborum block could reduce stress response,protect intestinal barrier function,and decrease the incidence of complications in patients undergoing radical surgery for gastric cancer.This technique has the potential for clinical applications. 展开更多
关键词 Ultrasound-guided quadratus lumborum block Radical gastric cancer surgery Stress response Intestinal barrier function Postoperative analgesia Rehabilitation
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239Pu alpha spectrum analysis based on PIPS detector response function and variations with vacuum and distance 被引量:7
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作者 Rui Shi Xian-Guo Tuo +3 位作者 Huai-Liang Li Jian-Bo Yang Yi Cheng Hong-Long Zheng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第1期20-26,共7页
Effect factors of the absorption of the source,air,entrance window,and dead layer of a detector must be considered in the measurement of monoenergetic alpha particles,along with statistical noise and other factors tha... Effect factors of the absorption of the source,air,entrance window,and dead layer of a detector must be considered in the measurement of monoenergetic alpha particles,along with statistical noise and other factors that collectively cause the alpha spectrum to exhibit a well-known low-energy tail.Therefore,the estabUshment of an alpha spectrum detector response function from the perspective of a signaling system must consider the various factors mentioned above.The detector response function is the convolution of an alphaparticle pulse function,two exponential functions,and a Gaussian function,followed by calculation of the parameters of the detector response function using the weighted leastsquares fitting method as proposed in this paper.In our experiment,^(239)Pu alpha spectra were measured by a highresolution,passivated implanted planar silicon(PIPS)detector at 10 levels of vacuum and 10 source-detector distances.The spectrum-fitting results were excellent as evaluated by reduced Chi-square(x^2) and correlation coefficients.Finally,the variation of parameters with vacuum level and source-detector distance was studied.Results demonstrate that σ,τ_1,and τ_2 exhibit no obvious trend of variation with vacuum in the range 2000-20,000 mTorr,and at a confidence level of 95%,the values of τ_1 and τ_2 decline in a similar fashion with source-detector distance by the power exponential function,while the value of a declines linearly. 展开更多
关键词 ALPHA spectrum DETECTOR response function WEIGHTED least SQUARES PIPS DETECTOR
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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 LiBiwen ZengXianwu 《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 responsex [FK(W1*3/4。*2/3]... 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 responsex [FK(W1*3/4。*2/3]′ 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 [FK(W1*3/4。*2/3]′ 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, τ is 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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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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Dynamic design of a nonlinear energy sink with NiTiNOL-steel wire ropes based on nonlinear output frequency response functions 被引量:7
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作者 Yewei ZHANG Kefan XU +3 位作者 Jian ZANG Zhiyu NI Yunpeng ZHU Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第12期1791-1804,共14页
A novel vibration isolation device called the nonlinear energy sink(NES)with NiTiNOL-steel wire ropes(NiTi-ST)is applied to a whole-spacecraft system.The NiTi-ST is used to describe the damping of the NES,which is cou... A novel vibration isolation device called the nonlinear energy sink(NES)with NiTiNOL-steel wire ropes(NiTi-ST)is applied to a whole-spacecraft system.The NiTi-ST is used to describe the damping of the NES,which is coupled with the modified Bouc-Wen model of hysteresis.The NES with NiTi-ST vibration reduction principle uses the irreversibility of targeted energy transfer(TET)to concentrate the energy locally on the nonlinear oscillator,and then dissipates it through damping in the NES with NiTi-ST.The generalized vibration transmissibility,obtained by the root mean square treatment of the harmonic response of the nonlinear output frequency response functions(NOFRFs),is first used as the evaluation index to analyze the whole-spacecraft system in the future.An optimization analysis of the impact of system responses is performed using different parameters of NES with NiTi-ST based on the transmissibility of NOFRFs.Finally,the effects of vibration suppression by varying the parameters of NiTi-ST are analyzed from the perspective of energy absorption.The results indicate that NES with NiTi-ST can reduce excessive vibration of the whole-spacecraft system,without changing its natural frequency.Moreover,the NES with NiTi-ST can be directly used in practical engineering applications. 展开更多
关键词 NONLINEAR energy sink(NES) vibration isolation NiTiNOL-steel wire ROPE (NiTi-ST) NONLINEAR output frequency response function(NOFRF) ROOT mean square TRANSMISSIBILITY
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Research on the iterative method for model updating based on the frequency response function 被引量:3
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作者 Wei-Ming Li Jia-Zhen Hong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期450-457,共8页
Model reduction technique is usually employed in model updating process. In this paper, a new model updat- ing method named as cross-model cross-frequency response function (CMCF) method is proposed and a new iterat... Model reduction technique is usually employed in model updating process. In this paper, a new model updat- ing method named as cross-model cross-frequency response function (CMCF) method is proposed and a new iterative method associating the model updating method with the mo- del reduction technique is investigated. The new model up- dating method utilizes the frequency response function to avoid the modal analysis process and it does not need to pair or scale the measured and the analytical frequency re- sponse function, which could greatly increase the number of the equations and the updating parameters. Based on the traditional iterative method, a correction term related to the errors resulting from the replacement of the reduction ma- trix of the experimental model with that of the finite element model is added in the new iterative method. Comparisons be- tween the traditional iterative method and the proposed itera- tive method are shown by model updating examples of solar panels, and both of these two iterative methods combine the CMCF method and the succession-level approximate reduc- tion technique. Results show the effectiveness of the CMCF method and the proposed iterative method . 展开更多
关键词 Model updating Model reduction Frequency response function ITERATION
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Uncertainty analysis of strain modal parameters by Bayesian method using frequency response function 被引量:3
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作者 徐丽 易伟建 易志华 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期183-189,共7页
Structural strain modes are able to detect changes in local structural performance, but errors are inevitably intermixed in the measured data. In this paper, strain modal parameters are considered as random variables,... Structural strain modes are able to detect changes in local structural performance, but errors are inevitably intermixed in the measured data. In this paper, strain modal parameters are considered as random variables, and their uncertainty is analyzed by a Bayesian method based on the structural frequency response function (FRF). The estimates of strain modal parameters with maximal posterior probability are determined. Several independent measurements of the FRF of a four-story reinforced concrete flame structural model were performed in the laboratory. The ability to identify the stiffness change in a concrete column using the strain mode was verified. It is shown that the uncertainty of the natural frequency is very small. Compared with the displacement mode shape, the variations of strain mode shapes at each point are quite different. The damping ratios are more affected by the types of test systems. Except for the case where a high order strain mode does not identify local damage, the first order strain mode can provide an exact indication of the damage location. 展开更多
关键词 frequency response function UNCERTAINTY strain mode Bayesian method local damage damage detection concrete flame
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