Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-di...Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-differentiable or explicit mathematical descriptions do not exist. Recently, evolutionary algorithms are gaining popularity for DOPs as they can be used as robust alternatives when the deterministic techniques are invalid. In this article, a technology named ranking-based mutation operator(RMO) is presented to enhance the previous differential evolution(DE) algorithms to solve DOPs using control vector parameterization. In the RMO, better individuals have higher probabilities to produce offspring, which is helpful for the performance enhancement of DE algorithms. Three DE-RMO algorithms are designed by incorporating the RMO. The three DE-RMO algorithms and their three original DE algorithms are applied to solve four constrained DOPs from the literature. Our simulation results indicate that DE-RMO algorithms exhibit better performance than previous non-ranking DE algorithms and other four evolutionary algorithms.展开更多
Effective Hamiltonians in periodically driven systems have received widespread attention for realization of novel quantum phases, non-equilibrium phase transition, and Majorana mode. Recently, the study of effective H...Effective Hamiltonians in periodically driven systems have received widespread attention for realization of novel quantum phases, non-equilibrium phase transition, and Majorana mode. Recently, the study of effective Hamiltonian using various methods has gained great interest. We consider a vector differential equation of motion to derive the effective Hamiltonian for any periodically driven two-level system, and the dynamics of the spin vector are an evolution under the Bloch sphere. Here, we investigate the properties of this equation and show that a sudden change of the effective Hamiltonian is expected. Furthermore, we present several exact relations, whose expressions are independent of the different starting points. Moreover, we deduce the effective Hamiltonian from the high-frequency limit, which approximately equals the results in previous studies. Our results show that the vector differential equation of motion is not affected by a convergence problem, and thus, can be used to numerically investigate the effective models in any periodic modulating system. Finally, we anticipate that the proposed method can be applied to experimental platforms that require time-periodic modulation, such as ultracold atoms and optical lattices.展开更多
The authors regret to report the following error made in“Spatiotemporal dynamics of neuron differentiation and migration in the developing human spinal cord;52(2025)-101283-1295;Doi:https://doi.org/10.1016/j.jgg.2025...The authors regret to report the following error made in“Spatiotemporal dynamics of neuron differentiation and migration in the developing human spinal cord;52(2025)-101283-1295;Doi:https://doi.org/10.1016/j.jgg.2025.08.004”.In Tables S1 and S2 in the supplementary materials of this paper,some items were written in Chinese.The corresponding pictures and tables were not uploaded in time.展开更多
AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially...AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially pancreatic carcinoma coexisting with chronic pancreatitis and tumor-forming pancreatitis. METHODS: Forty-eight consecutive patients who underwent surgery for a focal pancreatic mass, including pancreatic ductal carcinoma (n = 33), tumor-forming pancreatitis (n = 8), and islet cell tumor (n = 7), were reviewed. Five pancreatic carcinomas coexisted with longstanding chronic pancreatitis. The pancreatic TICs were obtained from the pancreatic mass and the pancreatic parenchyma both proximal and distal to the mass lesion in each patient, prior to surgery, and were classified into 4 types according to the time to a peak: 25 s and 1, 2, and 3 min after the bolus injection of contrast material, namely, type-Ⅰ, Ⅱ, Ⅲ, and Ⅳ, respectively, and were then compared to the corresponding histological pancreatic conditions. RESULTS: Pancreatic carcinomas demonstrated type-Ⅲ (n = 13) or Ⅳ (n = 20) TIC. Tumor-forming pancreatitis showed type-Ⅱ (n = 5) or Ⅲ (n = 3) TIC. All islet cell tumors revealed type-Ⅰ. The type-Ⅳ TIC was only recognized in pancreatic carcinoma, and the TIC of carcinoma always depicted the slowest rise to a peak among the 3 pancreatic TICs measured in each patient, even in patients with chronic pancreatitis.CONCLUSION: Pancreatic TIC from dynamic MRI provides reliable information for distinguishing pancreatic carcinoma from other pancreatic masses, and may enable us to avoid unnecessary pancreatic surgery and delays in making a correct diagnosis of pancreatic carcinoma, especially, in patients with longstanding chronic pancreatitis.展开更多
This paper presents a new three-level hierarchical control parallel algorithm for large-scale systems by spatial and time decomposition. The parallel variable metric (PVM)method is found to be promising third-level al...This paper presents a new three-level hierarchical control parallel algorithm for large-scale systems by spatial and time decomposition. The parallel variable metric (PVM)method is found to be promising third-level algorithm. In the subproblems of second-level, the constraints of the smaller subproblem requires that the initial state of a subproblem equals the terminal state of the preceding subproblem. The coordinating variables are updated using the modified Newton method. the low-level smaller subproblems are solved in parallel using extended differential dynamic programmeing (DDP). Numerical result shows that comparing with one level DDP. the PVM /DDP algorithm obtains significant speed-ups.展开更多
Precise control of a magnetically suspended double-gimbal control moment gyroscope （MSDGCMG） is of vital importance and challenge to the attitude positioning of spacecraft owing to its multivariable, nonlinear and s...Precise control of a magnetically suspended double-gimbal control moment gyroscope （MSDGCMG） is of vital importance and challenge to the attitude positioning of spacecraft owing to its multivariable, nonlinear and strong coupled properties. This paper proposes a novel linearization and decoupling method based on differential geometry theory and combines it with the internal model controller （IMC） to guarantee the system robustness to the external disturbance and parameter uncertainty. Furthermore, by introducing the dynamic compensation for the inner-gimbal rate-servo system and the magnetically suspended rotor （MSR） system only, we can eliminate the influence of the unmodeled dynamics to the decoupling control accuracy as well as save costs and inhibit noises effectively. The simulation results verify the nice decoupling and robustness performance of the system using the proposed method.展开更多
With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the...With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the interoperability with the existing ones necessitates the study of the assessment algorithm of this idea.In this paper,an assessment algorithm for interoperability comprehensive benefits based on the differential equation dynamical system is discussed.There are two important aspects in GNSS that interoperability will affect:one is the performance advancement;the other one is the cost of adopting interoperability.While researching the complex relationship between the performance and cost,we found this relationship is similar as what between prey and predator in biomathematics,so the Lotka-Volterra model used to depict the prey-predator relationship is a felicitous tool.After building a differential dynamical model,we analyze the existence and stability of the positive equilibrium in the model.Then a Cost-Effective Function of GNSS is constructed based on the positive equilibrium,which is employed to assess the interoperability,qualitatively and quantitatively.Finally,the paper demonstrates the significance of the model and its application by citing a numerical example.展开更多
In order to describe the interrelation forces among different regions during the economic growth, this paper introduces and analyzes the dynamical system model with the theory of differential systems dynamics. A pract...In order to describe the interrelation forces among different regions during the economic growth, this paper introduces and analyzes the dynamical system model with the theory of differential systems dynamics. A practical example based on a simplified model is given to analyze the dynamical process of Sichuan economy growth.展开更多
Porcine deltacoronavirus(PDCoV)exploits both human aminopeptidase N(hAPN)and porcine APN(pAPN)as receptors,with a higher affinity for hAPN than for pAPN through conserved interaction sites.However,despite this affinit...Porcine deltacoronavirus(PDCoV)exploits both human aminopeptidase N(hAPN)and porcine APN(pAPN)as receptors,with a higher affinity for hAPN than for pAPN through conserved interaction sites.However,despite this affinity,PDCoV is rarely pathogenic to humans,suggesting that the utilization dynamics of APN homologs by PDCoV are distinct,which is crucial in cross-species transmission but poorly understood.Here,we employed single-virus tracking to visualize and dissect the entry dynamics of PDCoV facilitated by APN.It was discovered that APN homologs bind PDCoV simultaneously,yet the times required for the initiation of membrane fusion and internalization differ significantly.Although high-affinity hAPN,rather than low-affinity pAPN,accompanies PDCoV during internalization,low-affinity pAPN initiates PDCoV internalization approximately 20 s faster than high-affinity hAPN,with caveolae-mediated endocytosis being more predominant and productive.Depending on the cell species,low-affinity pAPN induced a 5%to 25%greater proportion and a 0.6 to 4.3 min faster cell surface fusion,contributing to efficient infection.In contrast,high-affinity hAPN resulted in a 5%to 25%greater proportion and a 5 to 15 min faster endosomal fusion,potentially promoting immune evasion.We further demonstrated that the binding affinities between the PDCoV receptor-binding domain(RBD)and APN homologs are key determinants of the differential kinetics,driving flexible transitions between the two fusion pathways.This receptor affinity-selective PDCoV entry kinetics evolves an optimal balance of immune evasion and rapid infection,underscoring the potential for PDCoV interspecies transmission and the need for its vigilant surveillance.展开更多
An optimal feedback guidance law with disturbance rejection objective is proposed for endoatmospheric powered descent.This guidance law with an affine form is derived by solving a novel problem called Endoatmospheric ...An optimal feedback guidance law with disturbance rejection objective is proposed for endoatmospheric powered descent.This guidance law with an affine form is derived by solving a novel problem called Endoatmospheric Powered Descent Guidance with Disturbance Rejection(Endo-PDG-DR).The key idea of formulating the Endo-PDG-DR problem is dividing disturbances into two parts,modeled and unmodeled disturbances:the modeled disturbance is proactively exploited by augmenting it as a new state of a dynamics model;the unmodeled disturbance is reactively attenuated in terms of its effect on the guidance performance by adjoining a parameterized time-varying quadratic performance index in the proposed optimal guidance problem.A Pseudospectral Differential Dynamic Programming(PDDP)method is developed to solve the Endo-PDG-DR problem,and correspondingly a robust neighboring optimal state feedback law is obtained,which has two synergistic functionalities.One is adaptive optimal steering to accommodate the modeled disturbance,and the other is disturbance attenuation to compensate for the state perturbation effect induced by the unmodeled disturbance.Using the derived feedback guidance law,a disturbance rejection level is quantified,and is correspondingly optimized by designing a quadratic weighting parameter tuning law.The numerical computations of interest are performed within a pseudospectral setting,ensuring polynomial analytical solution,high computational efficiency,and reliable convergence.展开更多
A reliable transformer protection method is crucial for power systems. Aiming at improving the generalization performance and response speed of multi-feature fusion based transformer protection, this paper presents a ...A reliable transformer protection method is crucial for power systems. Aiming at improving the generalization performance and response speed of multi-feature fusion based transformer protection, this paper presents a dynamic differential current by fusing pre-disturbance and post-disturbance differential currents in real time then developing a dynamic differential current based transformer protection focusing on the feature changes of differential current. Generally, the image of differential current can comprehensively embody the feature changes resulting from any disturbance. In addition, a short window is sometimes sufficient to clearly reflect the internal fault because the differential current will instantly change when an internal fault occurs. Therefore, in order to identify the running states reliably in the shortest possible time, multiple images, including the differential current from a pre-disturbance one cycle to a post-disturbance different time, are combined by time order to define a dynamic differential current. After the protection method is started, this dynamic differential current serves as input for the deep learning algorithm to identify the running states in real time. Once the transformer is identified as a faulty one, a tripping signal is issued and the protection method stops. The dynamic model experiments show that the proposed protection method has a strong generalization ability and rapid response speed.展开更多
A switched linear quadratic（LQ） differential game over finite-horizon is investigated in this paper. The switching signal is regarded as a non-conventional player, afterwards the definition of Pareto efficiency is e...A switched linear quadratic（LQ） differential game over finite-horizon is investigated in this paper. The switching signal is regarded as a non-conventional player, afterwards the definition of Pareto efficiency is extended to dynamics switching situations to characterize the solutions of this multi-objective problem. Furthermore, the switched differential game is equivalently transformed into a family of parameterized single-objective optimal problems by introducing preference information and auxiliary variables. This transformation reduces the computing complexity such that the Pareto frontier of the switched LQ differential game can be constructed by dynamic programming. Finally, a numerical example is provided to illustrate the effectiveness.展开更多
In this paper we first investigate zero-sum two-player stochastic differential games with reflection, with the help of theory of Reflected Backward Stochastic Differential Equations （RBSDEs）. We will establish the d...In this paper we first investigate zero-sum two-player stochastic differential games with reflection, with the help of theory of Reflected Backward Stochastic Differential Equations （RBSDEs）. We will establish the dynamic programming principle for the upper and the lower value functions of this kind of stochastic differential games with reflection in a straightforward way. Then the upper and the lower value functions are proved to be the unique viscosity solutions to the associated upper and the lower Hamilton-Jacobi-Bettman-Isaacs equations with obstacles, respectively. The method differs significantly from those used for control problems with reflection, with new techniques developed of interest on its own. Further, we also prove a new estimate for RBSDEs being sharper than that in the paper of E1 Karoui, Kapoudjian, Pardoux, Peng and Quenez （1997）, which turns out to be very useful because it allows us to estimate the LP-distance of the solutions of two different RBSDEs by the p-th power of the distance of the initial values of the driving forward equations. We also show that the unique viscosity solution to the approximating Isaacs equation constructed by the penalization method converges to the viscosity solution of the Isaacs equation with obstacle.展开更多
Endochondral ossification is a physiological process involving a sequential formation of cartilage and bone tissues.Classically,cartilage and bone formation have been considered independent processes at cellular level...Endochondral ossification is a physiological process involving a sequential formation of cartilage and bone tissues.Classically,cartilage and bone formation have been considered independent processes at cellular level.However,the recently described multiple cell differentiation dynamics suggest that some bone cells are indeed the progeny of cartilage cells,or chondrocyte-derived osteoblasts.We hypothesized that the cartilage-to-bone phenotype transition is triggered by specific molecular events.First,the process was assessed in mouse bone tissue,and then,it was mimicked using in vivo cell implantation and in vitro serial differentiation protocols.Data indicates that cartilage cells transition to bone cell phenotype during postnatal physiological bone formation.This process can be reproduced using cartilage precursor cells coupled to specific implantation procedures or differentiation protocols.Gene expression profiling reveals that NOTCH,BMP and MAPK signaling pathways are relevant at the phenotype-switch,while the transcription factors Mesp1,Alx1,Grhl3 and Hmx3 are the feasible driver genes for chondrocyte-derived osteoblasts formation.Altogether,this report shows that endochondral ossification can be modeled using primary cell cultures and data indicate that this process is regulated by specific molecular events,previously described at skeleton morphogenesis during embryo development,and from now on also linkable to postnatal bone development and regeneration processes.展开更多
基金Supported by the National Natural Science Foundation of China(61333010,61134007and 21276078)“Shu Guang”project of Shanghai Municipal Education Commission,the Research Talents Startup Foundation of Jiangsu University(15JDG139)China Postdoctoral Science Foundation(2016M591783)
文摘Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-differentiable or explicit mathematical descriptions do not exist. Recently, evolutionary algorithms are gaining popularity for DOPs as they can be used as robust alternatives when the deterministic techniques are invalid. In this article, a technology named ranking-based mutation operator(RMO) is presented to enhance the previous differential evolution(DE) algorithms to solve DOPs using control vector parameterization. In the RMO, better individuals have higher probabilities to produce offspring, which is helpful for the performance enhancement of DE algorithms. Three DE-RMO algorithms are designed by incorporating the RMO. The three DE-RMO algorithms and their three original DE algorithms are applied to solve four constrained DOPs from the literature. Our simulation results indicate that DE-RMO algorithms exhibit better performance than previous non-ranking DE algorithms and other four evolutionary algorithms.
基金supported by the National Natural Science Foundation of China (Grant No. 11774328)。
文摘Effective Hamiltonians in periodically driven systems have received widespread attention for realization of novel quantum phases, non-equilibrium phase transition, and Majorana mode. Recently, the study of effective Hamiltonian using various methods has gained great interest. We consider a vector differential equation of motion to derive the effective Hamiltonian for any periodically driven two-level system, and the dynamics of the spin vector are an evolution under the Bloch sphere. Here, we investigate the properties of this equation and show that a sudden change of the effective Hamiltonian is expected. Furthermore, we present several exact relations, whose expressions are independent of the different starting points. Moreover, we deduce the effective Hamiltonian from the high-frequency limit, which approximately equals the results in previous studies. Our results show that the vector differential equation of motion is not affected by a convergence problem, and thus, can be used to numerically investigate the effective models in any periodic modulating system. Finally, we anticipate that the proposed method can be applied to experimental platforms that require time-periodic modulation, such as ultracold atoms and optical lattices.
文摘The authors regret to report the following error made in“Spatiotemporal dynamics of neuron differentiation and migration in the developing human spinal cord;52(2025)-101283-1295;Doi:https://doi.org/10.1016/j.jgg.2025.08.004”.In Tables S1 and S2 in the supplementary materials of this paper,some items were written in Chinese.The corresponding pictures and tables were not uploaded in time.
文摘AIM: To evaluate the ability of the time-signal intensity curve (TIC) of the pancreas obtained from dynamic contrast-enhanced magnetic resonance imaging (MRI) for differentiation of focal pancreatic masses, especially pancreatic carcinoma coexisting with chronic pancreatitis and tumor-forming pancreatitis. METHODS: Forty-eight consecutive patients who underwent surgery for a focal pancreatic mass, including pancreatic ductal carcinoma (n = 33), tumor-forming pancreatitis (n = 8), and islet cell tumor (n = 7), were reviewed. Five pancreatic carcinomas coexisted with longstanding chronic pancreatitis. The pancreatic TICs were obtained from the pancreatic mass and the pancreatic parenchyma both proximal and distal to the mass lesion in each patient, prior to surgery, and were classified into 4 types according to the time to a peak: 25 s and 1, 2, and 3 min after the bolus injection of contrast material, namely, type-Ⅰ, Ⅱ, Ⅲ, and Ⅳ, respectively, and were then compared to the corresponding histological pancreatic conditions. RESULTS: Pancreatic carcinomas demonstrated type-Ⅲ (n = 13) or Ⅳ (n = 20) TIC. Tumor-forming pancreatitis showed type-Ⅱ (n = 5) or Ⅲ (n = 3) TIC. All islet cell tumors revealed type-Ⅰ. The type-Ⅳ TIC was only recognized in pancreatic carcinoma, and the TIC of carcinoma always depicted the slowest rise to a peak among the 3 pancreatic TICs measured in each patient, even in patients with chronic pancreatitis.CONCLUSION: Pancreatic TIC from dynamic MRI provides reliable information for distinguishing pancreatic carcinoma from other pancreatic masses, and may enable us to avoid unnecessary pancreatic surgery and delays in making a correct diagnosis of pancreatic carcinoma, especially, in patients with longstanding chronic pancreatitis.
文摘This paper presents a new three-level hierarchical control parallel algorithm for large-scale systems by spatial and time decomposition. The parallel variable metric (PVM)method is found to be promising third-level algorithm. In the subproblems of second-level, the constraints of the smaller subproblem requires that the initial state of a subproblem equals the terminal state of the preceding subproblem. The coordinating variables are updated using the modified Newton method. the low-level smaller subproblems are solved in parallel using extended differential dynamic programmeing (DDP). Numerical result shows that comparing with one level DDP. the PVM /DDP algorithm obtains significant speed-ups.
文摘Precise control of a magnetically suspended double-gimbal control moment gyroscope （MSDGCMG） is of vital importance and challenge to the attitude positioning of spacecraft owing to its multivariable, nonlinear and strong coupled properties. This paper proposes a novel linearization and decoupling method based on differential geometry theory and combines it with the internal model controller （IMC） to guarantee the system robustness to the external disturbance and parameter uncertainty. Furthermore, by introducing the dynamic compensation for the inner-gimbal rate-servo system and the magnetically suspended rotor （MSR） system only, we can eliminate the influence of the unmodeled dynamics to the decoupling control accuracy as well as save costs and inhibit noises effectively. The simulation results verify the nice decoupling and robustness performance of the system using the proposed method.
基金supported by the National Natural Science Foundation of China (Grant Nos.11073022 and 71072160)the National Basic Research Program of China (Grant No.2007CB815502)the Western Light (Grant No.Y001YR4701)
文摘With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the interoperability with the existing ones necessitates the study of the assessment algorithm of this idea.In this paper,an assessment algorithm for interoperability comprehensive benefits based on the differential equation dynamical system is discussed.There are two important aspects in GNSS that interoperability will affect:one is the performance advancement;the other one is the cost of adopting interoperability.While researching the complex relationship between the performance and cost,we found this relationship is similar as what between prey and predator in biomathematics,so the Lotka-Volterra model used to depict the prey-predator relationship is a felicitous tool.After building a differential dynamical model,we analyze the existence and stability of the positive equilibrium in the model.Then a Cost-Effective Function of GNSS is constructed based on the positive equilibrium,which is employed to assess the interoperability,qualitatively and quantitatively.Finally,the paper demonstrates the significance of the model and its application by citing a numerical example.
基金This research is supported by the National Natural Science Foundation of China(No.70171021)
文摘In order to describe the interrelation forces among different regions during the economic growth, this paper introduces and analyzes the dynamical system model with the theory of differential systems dynamics. A practical example based on a simplified model is given to analyze the dynamical process of Sichuan economy growth.
基金supported by the National Key Research and Development Program of China(2021YFD1801104)the National Natural Science Foundation of China(32372991,32272996)+2 种基金Jiangsu Agricultural Science and Technology Innovation Fund(CX(23)1029)the Key Research and Development Program in Hunan Province,China(2023NK2017)the Fundamental Research Funds for the Central Universities(KJJQ2025021,KJYQ2025041).
文摘Porcine deltacoronavirus(PDCoV)exploits both human aminopeptidase N(hAPN)and porcine APN(pAPN)as receptors,with a higher affinity for hAPN than for pAPN through conserved interaction sites.However,despite this affinity,PDCoV is rarely pathogenic to humans,suggesting that the utilization dynamics of APN homologs by PDCoV are distinct,which is crucial in cross-species transmission but poorly understood.Here,we employed single-virus tracking to visualize and dissect the entry dynamics of PDCoV facilitated by APN.It was discovered that APN homologs bind PDCoV simultaneously,yet the times required for the initiation of membrane fusion and internalization differ significantly.Although high-affinity hAPN,rather than low-affinity pAPN,accompanies PDCoV during internalization,low-affinity pAPN initiates PDCoV internalization approximately 20 s faster than high-affinity hAPN,with caveolae-mediated endocytosis being more predominant and productive.Depending on the cell species,low-affinity pAPN induced a 5%to 25%greater proportion and a 0.6 to 4.3 min faster cell surface fusion,contributing to efficient infection.In contrast,high-affinity hAPN resulted in a 5%to 25%greater proportion and a 5 to 15 min faster endosomal fusion,potentially promoting immune evasion.We further demonstrated that the binding affinities between the PDCoV receptor-binding domain(RBD)and APN homologs are key determinants of the differential kinetics,driving flexible transitions between the two fusion pathways.This receptor affinity-selective PDCoV entry kinetics evolves an optimal balance of immune evasion and rapid infection,underscoring the potential for PDCoV interspecies transmission and the need for its vigilant surveillance.
基金co-supported by the National Natural Science Foundation of China(No.62103014)。
文摘An optimal feedback guidance law with disturbance rejection objective is proposed for endoatmospheric powered descent.This guidance law with an affine form is derived by solving a novel problem called Endoatmospheric Powered Descent Guidance with Disturbance Rejection(Endo-PDG-DR).The key idea of formulating the Endo-PDG-DR problem is dividing disturbances into two parts,modeled and unmodeled disturbances:the modeled disturbance is proactively exploited by augmenting it as a new state of a dynamics model;the unmodeled disturbance is reactively attenuated in terms of its effect on the guidance performance by adjoining a parameterized time-varying quadratic performance index in the proposed optimal guidance problem.A Pseudospectral Differential Dynamic Programming(PDDP)method is developed to solve the Endo-PDG-DR problem,and correspondingly a robust neighboring optimal state feedback law is obtained,which has two synergistic functionalities.One is adaptive optimal steering to accommodate the modeled disturbance,and the other is disturbance attenuation to compensate for the state perturbation effect induced by the unmodeled disturbance.Using the derived feedback guidance law,a disturbance rejection level is quantified,and is correspondingly optimized by designing a quadratic weighting parameter tuning law.The numerical computations of interest are performed within a pseudospectral setting,ensuring polynomial analytical solution,high computational efficiency,and reliable convergence.
基金supported by the the National Natural Science Foundation of China(51877167)。
文摘A reliable transformer protection method is crucial for power systems. Aiming at improving the generalization performance and response speed of multi-feature fusion based transformer protection, this paper presents a dynamic differential current by fusing pre-disturbance and post-disturbance differential currents in real time then developing a dynamic differential current based transformer protection focusing on the feature changes of differential current. Generally, the image of differential current can comprehensively embody the feature changes resulting from any disturbance. In addition, a short window is sometimes sufficient to clearly reflect the internal fault because the differential current will instantly change when an internal fault occurs. Therefore, in order to identify the running states reliably in the shortest possible time, multiple images, including the differential current from a pre-disturbance one cycle to a post-disturbance different time, are combined by time order to define a dynamic differential current. After the protection method is started, this dynamic differential current serves as input for the deep learning algorithm to identify the running states in real time. Once the transformer is identified as a faulty one, a tripping signal is issued and the protection method stops. The dynamic model experiments show that the proposed protection method has a strong generalization ability and rapid response speed.
基金supported by the National Natural Science Foundation of China under Grant No.61773098the 111 Project under Grant No.B16009
文摘A switched linear quadratic（LQ） differential game over finite-horizon is investigated in this paper. The switching signal is regarded as a non-conventional player, afterwards the definition of Pareto efficiency is extended to dynamics switching situations to characterize the solutions of this multi-objective problem. Furthermore, the switched differential game is equivalently transformed into a family of parameterized single-objective optimal problems by introducing preference information and auxiliary variables. This transformation reduces the computing complexity such that the Pareto frontier of the switched LQ differential game can be constructed by dynamic programming. Finally, a numerical example is provided to illustrate the effectiveness.
基金supported by the Agence Nationale de la Recherche (France), reference ANR-10-BLAN 0112the Marie Curie ITN "Controlled Systems", call: FP7-PEOPLE-2007-1-1-ITN, no. 213841-2+3 种基金supported by the National Natural Science Foundation of China (No. 10701050, 11071144)National Basic Research Program of China (973 Program) (No. 2007CB814904)Shandong Province (No. Q2007A04),Independent Innovation Foundation of Shandong Universitythe Project-sponsored by SRF for ROCS, SEM
文摘In this paper we first investigate zero-sum two-player stochastic differential games with reflection, with the help of theory of Reflected Backward Stochastic Differential Equations （RBSDEs）. We will establish the dynamic programming principle for the upper and the lower value functions of this kind of stochastic differential games with reflection in a straightforward way. Then the upper and the lower value functions are proved to be the unique viscosity solutions to the associated upper and the lower Hamilton-Jacobi-Bettman-Isaacs equations with obstacles, respectively. The method differs significantly from those used for control problems with reflection, with new techniques developed of interest on its own. Further, we also prove a new estimate for RBSDEs being sharper than that in the paper of E1 Karoui, Kapoudjian, Pardoux, Peng and Quenez （1997）, which turns out to be very useful because it allows us to estimate the LP-distance of the solutions of two different RBSDEs by the p-th power of the distance of the initial values of the driving forward equations. We also show that the unique viscosity solution to the approximating Isaacs equation constructed by the penalization method converges to the viscosity solution of the Isaacs equation with obstacle.
基金funded by Grants PID2021-127191OB-I00,RTI2018-101708-A-I00,PRE2018-084542 and PRE2022-102680 funded by MCIN/AEI/10.13039/501100011033 and by“ERDF A way of making Europe”Grant RYC2018-025502-I is funded by MCIN/AEI/10.13039/501100011033 and by“ESF Investing in your future”+1 种基金Grant MDM-20170720 Maria de Maeztu Units of Excellence Program funded by the Spanish State Research Agencysupported by Instituto de Salud CarlosⅢ,Infrastructure of Precision Medicine associated with Science and Technology(IMPaCT)of the Strategic Action in Health(iDATA-MP)。
文摘Endochondral ossification is a physiological process involving a sequential formation of cartilage and bone tissues.Classically,cartilage and bone formation have been considered independent processes at cellular level.However,the recently described multiple cell differentiation dynamics suggest that some bone cells are indeed the progeny of cartilage cells,or chondrocyte-derived osteoblasts.We hypothesized that the cartilage-to-bone phenotype transition is triggered by specific molecular events.First,the process was assessed in mouse bone tissue,and then,it was mimicked using in vivo cell implantation and in vitro serial differentiation protocols.Data indicates that cartilage cells transition to bone cell phenotype during postnatal physiological bone formation.This process can be reproduced using cartilage precursor cells coupled to specific implantation procedures or differentiation protocols.Gene expression profiling reveals that NOTCH,BMP and MAPK signaling pathways are relevant at the phenotype-switch,while the transcription factors Mesp1,Alx1,Grhl3 and Hmx3 are the feasible driver genes for chondrocyte-derived osteoblasts formation.Altogether,this report shows that endochondral ossification can be modeled using primary cell cultures and data indicate that this process is regulated by specific molecular events,previously described at skeleton morphogenesis during embryo development,and from now on also linkable to postnatal bone development and regeneration processes.
