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1.
Artigo em Inglês | MEDLINE | ID: mdl-37015382

RESUMO

In light of optimization theory and swarm evolutionary schemes, under multiple single-integrator mobile agents equipped with sensors and prompters, this article addresses a discrete-time multiagent source exploration problem with information prompts. Regarding information prompts as constraints on the unknown target, by virtue of penalty function skills (PFSs) and sequential unconstrained minimization techniques (SUMTs), the agents are driven toward the source under the guidance of the control strategy. In two cases of available and unavailable gradient information, a quantum potential well, an average optimal position estimator (AOPE), and a global optimal position estimator (GOPE) are introduced into swarm evolutionary schemes with a periodically oscillating weight, such that distributed cooperative quantum learning (DCQL) policy is proposed as a control strategy under communication restrictions, where AOPE and GOPE are developed relying on distributed consensus theory. In particular, when the gradient is unavailable, we put forth an adaptive generalized Bernstein neural network (AGBNN) to replace it based on excellent properties of Bernstein polynomials and adaptive approaches. Further, a performance analysis for the proposed policy is executed on the convergence and computational complexity, which ensures the accuracy and efficiency of the source exploration in theory. Ultimately, a simulation test is carried out, and the results validate the practicability and effectiveness of the offered method.

2.
IEEE Trans Cybern ; 52(8): 7541-7551, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33417574

RESUMO

This article studies the problem of synthesis with guaranteed cost and less human intervention for linear human-in-the-loop (HiTL) control systems. Initially, the human behaviors are modeled via a hidden controlled Markov process, which not only considers the inference's stochasticity and observation's uncertainty of the human internal state but also takes the control input to human into account. Then, to integrate both models of human and machine as well as their interaction, a hidden controlled Markov jump system (HCMJS) is constructed. With the aid of the stochastic Lyapunov functional together with the bilinear matrix inequality technique, a sufficient condition for the existence of human-assistance controllers is derived on the basis of the HCMJS model, which not only guarantees the stochastic stability of the closed-loop HiTL system but also provides a prescribed upper bound for the quadratic cost function. Moreover, to achieve less human intervention while meeting the desired cost level, an algorithm that mixes the particle swarm optimization and linear matrix inequality technique is proposed to seek a suitable feedback control law to the human and a human-assistance control law to the machine. Finally, the proposed method is applied to a driver-assistance system to verify its effectiveness.


Assuntos
Algoritmos , Dinâmica não Linear , Simulação por Computador , Retroalimentação , Humanos , Cadeias de Markov
3.
J Plast Reconstr Aesthet Surg ; 75(1): 325-331, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34627716

RESUMO

Index finger dorsal island flaps were frequently utilized by hand surgeons to reconstruct thumb defects. However, the blood supply of the traditional index finger dorsal island flap comes from the first dorsal metacarpal artery, which has a smaller diameter, more anatomical variation, and can be injured in conjunction with thumb injuries. Therefore, we design an alternative index finger dorsal island flap based on the second dorsal metacarpal artery to treat thumb skin defects. From August 2015 to October 2018, we used the index finger dorsal island flaps with the second dorsal metacarpal artery to treat 11 patients with thumb skin defects. All the flaps and skin grafts survived completely without complications. At the last follow-up, the mean 2PD of the flap was 6.4 mm (45.5% for excellent, 54.5% for good), the mean ROM of the injured thumbs was 115.9° (72.7% for excellent, 27.3% for good), and the mean cosmetics score was 8.6. Our results demonstrate that the index finger dorsal island flap with the second dorsal metacarpal artery is suitable for the reconstruction of thumb skin defects. The flap has an excellent survival rate and good coverage with satisfactory results and represents a promising treatment for the selected patients. Level of Evidence: Therapeutic, level IV.


Assuntos
Traumatismos dos Dedos , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Artérias/cirurgia , Traumatismos dos Dedos/cirurgia , Dedos/cirurgia , Humanos , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Polegar/lesões , Polegar/cirurgia , Resultado do Tratamento
4.
ISA Trans ; 92: 35-48, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30853103

RESUMO

For fractional-order chaotic systems with unequal orders between 0 and 1, a synchronization based on them and its application in secret communication are investigated in the presence of parameter uncertainty and unknown external disturbance. Firstly, through using fractional calculus theory and adaptive control method, we design a feedback controller to achieve the synchronization between the systems. Next, in order to make the controller better apply to secret communication, an optimization policy is provided for it by some performance indicator about state variables in the error system. Meanwhile, to further enhance the performance of the controller, we introduce an interval estimation (IE) strategy into quantum particle swarm optimization (QPSO) algorithm to improve it, and then this algorithm is used to optimize the controller parameters. In addition, for the security of signal transmission, a feedback mechanism with encrypted signal is offered in secret communication. Finally, by comparison, simulation experiments verify the validity and applicability of the proposed method.

5.
Mech Ageing Dev ; 131(11-12): 723-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21035481

RESUMO

Although salidroside and salidroside-like compounds are considered as most critical constitutes needed and responsible for multiple therapeutic benefits of Rhodiola rosea L., including anti-aging, direct demonstration regarding the role of salidroside in anti-aging process is still deficient. In this study, we selected the H(2)O(2)-induced premature senescence model in human fetal lung diploid fibroblasts to investigate the protection of salidroside against aging in vitro and associated molecular mechanisms. We found that salidroside considerably reversed senescence-like phenotypes in the oxidant challenged model, including alterations of morphology, cell cycle, SA-ß-gal staining, DNA damage, as well as related molecules expression such as p53, p21 and p16. The protection occurred in a dose-dependent manner, with 5µM offering best efficacy. The proposed antioxidant property of the compound was confirmed in this cellular system, and thus at least partially accounted for the protection of the compound against premature senescence. Similar protection of salidroside against replicative senescence was observed as well. Interestingly, the regulation of senescence-related molecules by salidroside involved ROS-irrelevant mechanisms in both models. This finding presents salidroside as an attractive agent with potential to retard aging and attenuate age-related diseases in humans.


Assuntos
Senilidade Prematura/prevenção & controle , Antioxidantes/farmacologia , Senescência Celular/efeitos dos fármacos , Citoproteção , Glucosídeos/farmacologia , Peróxido de Hidrogênio/antagonistas & inibidores , Fenóis/farmacologia , Senilidade Prematura/patologia , Antioxidantes/química , Biomarcadores/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Dano ao DNA/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Glucosídeos/química , Humanos , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fenóis/química , Proteínas/metabolismo , Rhodiola/química , Superóxido Dismutase/metabolismo
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