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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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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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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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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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Study on topographic compensation model of the Okinawa Trough Ⅱ. Geological interpretation of isostatic response function of the Okinawa Trough 被引量:2
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作者 Xin Baisen Liu Baohua and Xia Zhifeng 1. Ocean University of Qingdao, Qingdao 266003, China 2. First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China (Received October 12, 1997 accepted July 17, 1998) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1999年第2期273-278,共6页
Based on regional compensation model and experimental isostasy, the isostatic response function of the Okinawa Trough is calculated by using gravity and topographic data. The results are shown as follows: the effectiv... Based on regional compensation model and experimental isostasy, the isostatic response function of the Okinawa Trough is calculated by using gravity and topographic data. The results are shown as follows: the effective elastic thickness of the plate and compensation depth in the southern Okinawa Trough is obviously greater than those in the middle Okinawa Trough. In reference with other geological and geophysical data, the differences between the two portions are explained to be caused mainly by their differences in temperature of the lithosphere and the compensation mechanism. 展开更多
关键词 OKINAWA TROUGH COMPENSATION model isostatic response function topographic LOAD loads from below
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Study on topographic compensation model of the Okinawa Trough I. Calculation of theoretical isostatic response function 被引量:2
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作者 Liu Baohua Wu Jinlong +1 位作者 Xin Baisen and Peng Chao 1. First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 2. Ocean University of Qingdao, Qingdao 266003, China (Received October 12, 1997 accepted July 17, 1998) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1999年第2期267-272,共6页
Based on regional compensation and experimental isostasy, the calculating formula of theoretical isostatic response function is deduced when the loads on top correlate with loads from below. A variety of curves of the... Based on regional compensation and experimental isostasy, the calculating formula of theoretical isostatic response function is deduced when the loads on top correlate with loads from below. A variety of curves of theoretical isostatic response function were calculated with different effective elastic thickness of the plate and by using different proportions between loads on top and loads from below. And preliminary discussion is made on shapes of the curves. 展开更多
关键词 OKINAWA TROUGH isostatic COMPENSATION topographic LOAD loads from below isostatic response function
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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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The Dynamical Behavior of a Certain Predator-Prey System with Holling Type II Functional Response 被引量:5
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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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Predictive functional control of integrating process based on impulse response 被引量:2
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作者 BinZHANG PingLI WeidongZHANG 《控制理论与应用(英文版)》 EI 2004年第2期196-200,共5页
The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of ... The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of the load disturbance, a novel error compensation method is proposed. Then predictive functional control of integrating process is designed. The method given generates a simple control structure, which can significandy reduce online computation. Furthermore, the tuning of the controller is fairly straightforward. Simulation results indicate that the designed control system is relatively robust to the parameters variation of the process. 展开更多
关键词 Integrating process Time delay Impulse response Predictive functional control (PFC)
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Global Asymptotic Stability and Hopf Bifurcation in a Homogeneous Diffusive Predator-Prey System with Holling Type II Functional Response 被引量:3
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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389-406,共18页
In this paper, we considered a homogeneous reaction-diffusion predator-prey system with Holling type II functional response subject to Neumann boundary conditions. Some new sufficient conditions were analytically esta... In this paper, we considered a homogeneous reaction-diffusion predator-prey system with Holling type II functional response subject to Neumann boundary conditions. Some new sufficient conditions were analytically established to ensure that this system has globally asymptotically stable equilibria and Hopf bifurcation surrounding interior equilibrium. In the analysis of Hopf bifurcation, based on the phenomenon of Turing instability and well-done conditions, the system undergoes a Hopf bifurcation and an example incorporating with numerical simulations to support the existence of Hopf bifurcation is presented. We also derived a useful algorithm for determining direction of Hopf bifurcation and stability of bifurcating periodic solutions correspond to j &#8800;0 and j = 0, respectively. Finally, all these theoretical results are expected to be useful in the future study of dynamical complexity of ecological environment. 展开更多
关键词 HOLLING Type II functional response REACTION-DIFFUSION PREDATOR-PREY System Global Stability TURING Instability Hopf Bifurcation
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Board-invited review: Sensitivity and responses of functional groups to feed processing methods on a molecular basis 被引量:2
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作者 Peiqiang Yu 《Journal of Animal Science and Biotechnology》 SCIE CAS 2013年第1期1-4,共4页
In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore... In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques: such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals. 展开更多
关键词 Sensitivity and responses of functional groups Molecular structures Feed processing Nutrient utilizationand availability
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Multiple-response optimization for melting process of aluminum melting furnace based on response surface methodology with desirability function 被引量:3
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作者 周孑民 王计敏 +2 位作者 闫红杰 李世轩 贵广臣 《Journal of Central South University》 SCIE EI CAS 2012年第10期2875-2885,共11页
To reduce the fuel consumption and emissions and also enhance the molten aluminum quality, a mathematical model with user-developed melting model and burning capacity model, were established according to the features ... To reduce the fuel consumption and emissions and also enhance the molten aluminum quality, a mathematical model with user-developed melting model and burning capacity model, were established according to the features of melting process of regenerative aluminum melting furnaces. Based on validating results by heat balance test for an aluminum melting furnace, CFD (computational fluid dynamics) technique, in association with statistical experimental design were used to optimize the melting process of the aluminum melting furnace. Four important factors influencing the melting time, such as horizontal angle between burners, height-to-radius ratio, natural gas mass flow and air preheated temperature, were identified by PLACKETT-BURMAN design. A steepest descent method was undertaken to determine the optimal regions of these factors. Response surface methodology with BOX-BEHNKEN design was adopted to further investigate the mutual interactions between these variables on RSD (relative standard deviation) of aluminum temperature, RSD of furnace temperature and melting time. Multiple-response optimization by desirability function approach was used to determine the optimum melting process parameters. The results indicate that the interaction between the height-to-radius ratio and horizontal angle between burners affects the response variables significantly. The predicted results show that the minimum RSD of aluminum temperature (12.13%), RSD of furnace temperature (18.50%) and melting time (3.9 h) could be obtained under the optimum conditions of horizontal angle between burners as 64°, height-to-radius ratio as 0.3, natural gas mass flow as 599 m3/h, and air preheated temperature as 639 ℃. These predicted values were further verified by validation experiments. The excellent correlation between the predicted and experimental values confirms the validity and practicability of this statistical optimum strategy. 展开更多
关键词 aluminum melting furnace melting process response surface methodology desirability function multiple response parameter optimization numerical simulation PLACKETT-BURMAN design BOX-BEHNKEN design
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