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Fault detection observer design for networked control system with long time-delays and data packet dropout 被引量:3
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作者 Xuan Li Xiaobei Wu +1 位作者 Zhiliang Xu Cheng Huang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期877-882,共6页
Focusing on the networked control system with long time-delays and data packet dropout,the problem of observerbased fault detection of the system is studied.According to conditions of data arrival of the controller,th... Focusing on the networked control system with long time-delays and data packet dropout,the problem of observerbased fault detection of the system is studied.According to conditions of data arrival of the controller,the state observers of the system are designed to detect faults when they occur in the system.When the system is normal,the observers system is modeled as an uncertain switched system.Based on the model,stability condition of the whole system is given.When conditions are satisfied,the system is asymptotically stable.When a fault occurs,the observers residual can change rapidly to detect the fault.A numerical example shows the effectiveness of the proposed method. 展开更多
关键词 networked control system fault detection long timedelays data packet dropout.
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长虚拟链环的Long Virtual Quandle不变量
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作者 毛宁 沈广艳 《东北师大学报(自然科学版)》 北大核心 2026年第1期12-15,共4页
将虚拟纽结的Quandle扩展到长虚拟链环上,定义了长虚拟链环的Long Virtual Quandle,并证明了它是长虚拟链环在广义R-移动下的不变量.
关键词 虚拟链环 长虚拟链环 多项式 QUANDLE
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Probabilistic distribution and stochastic P-bifurcation of a nonlinear energy-regenerative suspension system with time-delayed feedback control
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作者 Zhao-Bin Zeng Ya-Hui Sun Yang Liu 《Chinese Physics B》 2026年第1期322-330,共9页
Energy-regenerative suspension combined with piezoelectric and electromagnetic transduction has evolved into a core technological pathway in advancing automotive design paradigms.With the aim of improving energy harve... Energy-regenerative suspension combined with piezoelectric and electromagnetic transduction has evolved into a core technological pathway in advancing automotive design paradigms.With the aim of improving energy harvesting performance,time-delayed feedback control is widely used in an energy-regenerative suspension system under different external disturbances in this paper.Meanwhile,limited research has addressed the stochastic dynamics of time-delayed nonlinear energy-regenerative suspension systems.Different from previous studies,this work studies the stochastic response and P-bifurcation of the nonlinear energy-regenerative suspension system with time-delayed feedback control.Firstly,an approximately equivalent dimension reduction system is established by the variable transformation method,and then the stationary probability density function of amplitude is obtained by the stochastic averaging method.Secondly,the precision of the method used in this work is verified by comparing the numerical solutions with the analytical results.Finally,based on the stationary probability density function,the influence of system parameters on stochastic P-bifurcation and the mean output power is discussed. 展开更多
关键词 energy-regenerative suspension stochastic P-bifurcation stochastic resonance time-delayed feedback control
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Impact of nutrition on long COVID
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作者 Subramanian Thangaleela Chin-Kun Wang 《Sports Medicine and Health Science》 2026年第2期128-144,共17页
Long COVID is characterized by a group of persistent symptoms following the acute SARS-COV2 infection, which presented a multifaceted challenge to the healthcare systems all over the globe. The long COVID symptoms spa... Long COVID is characterized by a group of persistent symptoms following the acute SARS-COV2 infection, which presented a multifaceted challenge to the healthcare systems all over the globe. The long COVID symptoms span various organ systems including the respiratory, cardiovascular, gastrointestinal, and neurological manifestations. Mitochondrial dysfunction and immune dysregulation play crucial roles in the long COVID pathophysiology. Recently nutritional intervention gained much attention in managing post-viral syndromes. Effective interventions like supplementation of omega-3 fatty acid, macro and micro nutrients, and vitamins help to reduce systemic inflammation and counteract muscle wasting. Other approaches like nutritional recovery, dietetic interventions, continuous nutritional care post-hospital discharge, nutritional rehabilitation programs,whole-diet approaches like Mediterranean diet, plant-based diet, and caloric optimization, improve overall functional recovery. Physical activity and exercise regimes have been shown to improve fatigue, dyspnea, and cognitive function. Tailored exercise regimes may promote safe rehabilitation. Certain ineffective interventions,such as non-personalized approaches, high dose of antioxidants, use of herbal products that are not clinically validated need to be addressed. Dietary interventions such as personalized nutritional counseling have been demonstrated to improve physical performance in long COVID patients. Further research is needed to refine protocols and identify optimal combinations of dietary and movement-based therapies to support the recovery of long-COVID patients. This narrative review focuses on the ongoing researches that reveals the intricate relationship between nutrition and long COVID recovery and also establishes effective protocols for nutritional care. 展开更多
关键词 long COVID Metabolic reprogramming Immune dysregulation MALNUTRITION Nutritional intervention LACTOFERRIN Rehabilitation
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RP11-Derived Long Non-Coding RNAs in Hepatocellular Carcinoma:Hidden Treasures in Plain Sight
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作者 Se Ha Jang Hyung Seok Kim Jung Woo Eun 《Oncology Research》 2026年第1期89-104,共16页
Hepatocellular carcinoma(HCC)remains one of the most prevalent and lethal malignancies worldwide.Long non-coding RNAs(lncRNAs)have emerged as crucial regulators of gene expression and cancer progression,yet the functi... Hepatocellular carcinoma(HCC)remains one of the most prevalent and lethal malignancies worldwide.Long non-coding RNAs(lncRNAs)have emerged as crucial regulators of gene expression and cancer progression,yet the functional diversity of RP11-derived lncRNAs—originally mapped to bacterial artificial chromosome(BAC)clones from the Roswell Park Cancer Institute—has only recently begun to be appreciated.This mini-review aims to systematically synthesize current findings on RP11-derived lncRNAs in HCC,outlining their genomic origins,molecular mechanisms,and biological significance.We highlight their roles in metabolic reprogramming,microRNA network modulation,and tumor progression,as well as their diagnostic and prognostic value in tissue and serum-based analyses.Finally,we discuss therapeutic opportunities and propose future directions to translate RP11-derived lncRNAs into clinically actionable biomarkers and targets for precision liver cancer therapy. 展开更多
关键词 Hepatocellular carcinoma long non-coding RNA RP11-derived lncRNA BIOMARKER therapeutic target
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Research on the Efficacy of Autologous Periosteum Graft Combined with PRP in the Treatment of Long Bone Fractures in the Extremities
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作者 Xiang Chen 《Journal of Clinical and Nursing Research》 2026年第1期323-330,共8页
Objective:To analyze the clinical application value of autologous periosteum graft combined with platelet-rich plasma(PRP)in the treatment of long bone fractures in the extremities.Methods:A total of 40 patients with ... Objective:To analyze the clinical application value of autologous periosteum graft combined with platelet-rich plasma(PRP)in the treatment of long bone fractures in the extremities.Methods:A total of 40 patients with long bone fractures in the extremities admitted to Santai Hospital Affiliated to North Sichuan Medical College from January 2023 to January 2025 were included,including cases of upper extremity forearm fractures and lower extremity femoral and tibial fractures.The patients were evenly divided using a random number table,with the control group undergoing open reduction and internal fixation(ORIF)combined with autologous periosteum graft,and the observation group undergoing ORIF,autologous periosteum graft,and PRP injection.Surgical indicators,complication rates,excellent fracture healing rates,functional satisfaction,and joint range of motion were compared between the two groups.Results:The surgical indicators in the observation group were similar to those in the control group(p>0.05).The complication rate in the observation group was lower than that in the control group,while the excellent fracture healing rate and functional satisfaction were higher in the observation group(p<0.05).Conclusion:Autologous periosteum graft combined with PRP technology is safe and reliable for the treatment of long bone fractures in the extremities,with satisfactory clinical outcomes. 展开更多
关键词 Periosteum graft long bones of the extremities PRP Complication rate Fracture healing
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Real-time decision support for bolter recovery safety:Long short-term memory network-driven aircraft sequencing
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作者 Wei Han Changjiu Li +4 位作者 Xichao Su Yong Zhang Fang Guo Tongtong Yu Xuan Li 《Defence Technology(防务技术)》 2026年第2期184-205,共22页
The highly dynamic nature,strong uncertainty,and coupled multiple safety constraints inherent in carrier aircraft recovery operations pose severe challenges for real-time decision-making.Addressing bolter scenarios,th... The highly dynamic nature,strong uncertainty,and coupled multiple safety constraints inherent in carrier aircraft recovery operations pose severe challenges for real-time decision-making.Addressing bolter scenarios,this study proposes an intelligent decision-making framework based on a deep long short-term memory Q-network.This framework transforms the real-time sequencing for bolter recovery problem into a partially observable Markov decision process.It employs a stacked long shortterm memory network to accurately capture the long-range temporal dependencies of bolter event chains and fuel consumption.Furthermore,it integrates a prioritized experience replay training mechanism to construct a safe and adaptive scheduling system capable of millisecond-level real-time decision-making.Experimental demonstrates that,within large-scale mass recovery scenarios,the framework achieves zero safety violations in static environments and maintains a fuel safety violation rate below 10%in dynamic scenarios,with single-step decision times at the millisecond level.The model exhibits strong generalization capability,effectively responding to unforeseen emergent situations—such as multiple bolters and fuel emergencies—without requiring retraining.This provides robust support for efficient carrier-based aircraft recovery operations. 展开更多
关键词 Carrier-based aircraft Recovery scheduling Deep reinforcement learning long short-term memory networks Dynamic real-time decision-making
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Research on fuzzy self-adaptive PI-Smith control in long time-delay system 被引量:3
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作者 WEI Qiu-yue WANG Wen-qing 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2011年第5期114-117,128,共5页
The long time-delay often exists in industrial process. In order to overcome the big overshoot and long regulating time of the long time-delay system control, a new fuzzy self-adaptive PI-Smith control method is propo... The long time-delay often exists in industrial process. In order to overcome the big overshoot and long regulating time of the long time-delay system control, a new fuzzy self-adaptive PI-Smith control method is proposed. This method combines the Smith predictive control with fuzzy self-adaptive proportional-integral (PI) control. The traditional proportional-integral-derivative (PID) controller in Smith predictive control is replaced by fuzzy PI controller which utilizes the principle of fuzzy control to tune parameters of PI controller on-line. The results of simulation for electric furnace show that the method has the advantages of shortening regulating time, no overshoot, no steady-state error, excellent control accuracy, and good adaptive ability to the change of system model. 展开更多
关键词 SELF-ADAPTIVE fuzzy PI control Smith predictive control long time-delay
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Virial⁃Peng⁃Long状态方程优化及应用
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作者 彭钺 张蕾 +4 位作者 谢明伟 袁晓霞 麻宏亮 李芳 李明 《含能材料》 北大核心 2025年第4期374-383,共10页
为进一步提升Virial⁃Peng⁃Long(VPL)状态方程(equation of state,EOS)描述气相爆轰产物热力学关系准确性,实现VPL EOS对高密度炸药爆轰性能预测准确性提升。在理论分析基础上,通过修正Exponential⁃6(Exp⁃6)势函数近程排斥段存在的异常拐... 为进一步提升Virial⁃Peng⁃Long(VPL)状态方程(equation of state,EOS)描述气相爆轰产物热力学关系准确性,实现VPL EOS对高密度炸药爆轰性能预测准确性提升。在理论分析基础上,通过修正Exponential⁃6(Exp⁃6)势函数近程排斥段存在的异常拐点,得到势能曲线全域连续、光滑的指数型分子势Exponential⁃6modified(Exp⁃6m),基于Exp⁃6m势2~5阶维里系数理论值建立了改进形式的高阶维里型气相爆轰产物状态方程:Virial⁃Peng⁃Long⁃modified(VPLm)EOS。一方面,应用VPLm EOS计算了太安(PETN)、硝化甘油(NG)等低碳/无碳炸药,以及六硝基六氮杂异伍兹烷(CL⁃20)等具有高能量密度炸药的爆轰Chapmann⁃Jouguet(C⁃J)参数,结果表明基于VPLm EOS能够准确评价炸药的爆轰性能。其中对PETN在较高密度下爆压预测偏差普遍低于1.5%,对高密度CL⁃20爆速预测偏差能控制在1.6%以内,计算准确性相比VPL EOS有了显著提升。另一方面,应用VPLm EOS计算了典型含金属起爆药叠氮化铅(LA)在不同密度下的爆速,结果表明VPLm EOS对LA爆速的预测准确性好于Explo5和CHEETAH,相比VPL EOS对LA在较高密度下的爆速计算更为准确。 展开更多
关键词 Virial⁃Peng⁃long状态方程 分子势函数 爆轰性能 叠氮化铅(LA)
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Composite anti-disturbance predictive control of unmanned systems with time-delay using multi-dimensional Taylor network 被引量:1
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作者 Chenlong LI Wenshuo LI Zejun ZHANG 《Chinese Journal of Aeronautics》 2025年第7期589-600,共12页
A composite anti-disturbance predictive control strategy employing a Multi-dimensional Taylor Network(MTN)is presented for unmanned systems subject to time-delay and multi-source disturbances.First,the multi-source di... A composite anti-disturbance predictive control strategy employing a Multi-dimensional Taylor Network(MTN)is presented for unmanned systems subject to time-delay and multi-source disturbances.First,the multi-source disturbances are addressed according to their specific characteristics as follows:(A)an MTN data-driven model,which is used for uncertainty description,is designed accompanied with the mechanism model to represent the unmanned systems;(B)an adaptive MTN filter is used to remove the influence of the internal disturbance;(C)an MTN disturbance observer is constructed to estimate and compensate for the influence of the external disturbance;(D)the Extended Kalman Filter(EKF)algorithm is utilized as the learning mechanism for MTNs.Second,to address the time-delay effect,a recursiveτstep-ahead MTN predictive model is designed utilizing recursive technology,aiming to mitigate the impact of time-delay,and the EKF algorithm is employed as its learning mechanism.Then,the MTN predictive control law is designed based on the quadratic performance index.By implementing the proposed composite controller to unmanned systems,simultaneous feedforward compensation and feedback suppression to the multi-source disturbances are conducted.Finally,the convergence of the MTN and the stability of the closed-loop system are established utilizing the Lyapunov theorem.Two exemplary applications of unmanned systems involving unmanned vehicle and rigid spacecraft are presented to validate the effectiveness of the proposed approach. 展开更多
关键词 Multi-dimensional Taylor network Composite anti-disturbance Predictive control Unmanned systems Multi-source disturbances time-delay
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Developing color-tunable long afterglow anti-counterfeiting materials using cucurbit[6]uril and classical aggregation-caused quenching compounds through multiple non-covalent interactions 被引量:1
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作者 Xingyue Yuan Li Wu +5 位作者 Qiuyu Peng Yanyan Tang Mingxu Wang Yuhang Wei Zhu Tao Xin Xiao 《Chinese Chemical Letters》 2025年第9期345-349,共5页
This investigation focuses on the utilization of cucurbit[6]uril(Q[6])as the host compound for the development of long-lasting afterglow materials.By strategically manipulating the outer surface interactions of Q[6],c... This investigation focuses on the utilization of cucurbit[6]uril(Q[6])as the host compound for the development of long-lasting afterglow materials.By strategically manipulating the outer surface interactions of Q[6],classical aggregation-caused quenching(ACQ)compounds such as fluorescein sodium(FluNa)and calcein sodium(CalNa)were transformed into afterglow materials with varying colors and durations upon exposure to ultraviolet light.This transformation was facilitated through a host-vip doping method combined with coordination with metal ions.Even at a reduced doping concentration of 5×10^(-5)wt%,the materials exhibit remarkable afterglow properties,lasting up to 2 s,with a phosphorescence lifetime of up to 150 ms.Moreover,by adjusting the concentration of the vip compound,the persistent luminescence color of the materials could be easily transitioned from orange to yellow and subsequently to green.These findings suggest that the developed afterglow materials hold significant potential for multilevel anti-counterfeiting and information encryption applications when exposed to ultraviolet light.The supramolecular assembly strategy,which relies on the outer surface interactions of cucurbit[n]uril,offers a simpler and more efficient approach to crafting multi-color luminescent materials.Additionally,this method opens avenues for enhancing the application potential of aggregation-caused quenching(ACQ)compounds in various technological domains. 展开更多
关键词 Cucurbit[n]uril Room-temperature phosphorescence long afterglow ANTI-COUNTERFEITING SELF-ASSEMBLY
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Long burn arc powered explicit guidance algorithm for Earth-to-Moon missions 被引量:1
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作者 Haifeng HU Liang YAN +2 位作者 Cong WANG Jinlin WANG Pengjie XIANG 《Chinese Journal of Aeronautics》 2025年第12期337-347,共11页
Earth-to-Moon missions with low thrust-to-weight ratios present unique challenges for exoatmospheric guidance,and the existing algorithms are ineffective for the unprecedentedly long burn arcs and high orbital eccentr... Earth-to-Moon missions with low thrust-to-weight ratios present unique challenges for exoatmospheric guidance,and the existing algorithms are ineffective for the unprecedentedly long burn arcs and high orbital eccentricities.To address these challenges,a Long Burn Arc Powered Explicit Guidance(LBA-PEG)algorithm is developed and compared with the existing algorithms.In the proposed LBA-PEG algorithm,a fully numerical thrust prediction method is developed to accurately predict the highly nonlinear thrust effects over long burn arcs.Moreover,a real-time Newton correction method is proposed to correct the orbit injection point,remedying the position-velocity coupling induced by high orbital eccentricities.The comparison between the proposed algorithm and the existing algorithm shows that the proposed algorithm surpasses the existing ones by significantly enhancing fuel efficiency and improving tolerance to thrust decrease.The proposed LBA-PEG algorithm can adapt to a 65%thrust decrease,which is 12%–22%larger than that of the existing algorithms,and it can still reliably converge and complete the guidance mission even when the length of the burn arc exceeds 90°.The proposed LBA-PEG highlights the algorithm's adaptability for long burn arc missions,especially in critical scenarios such as manned Earth-to-Moon missions. 展开更多
关键词 Large eccentricity Launch vehicle long burn arc Numerical guidance method Powered explicit guidance
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Mechanisms underlying hepatocellular carcinoma progression through N6-methyladenosine modifications of long non-coding RNA 被引量:1
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作者 Ning Wang Fei-Tian Min +1 位作者 Wei-Bo Wen Huan-Tian Cui 《World Journal of Gastroenterology》 2025年第21期135-139,共5页
Hepatocellular carcinoma(HCC)is a highly lethal malignancy with limited treatment options,particularly for patients with advanced stages of the disease.Sorafenib,the standard first-line therapy,faces significant chall... Hepatocellular carcinoma(HCC)is a highly lethal malignancy with limited treatment options,particularly for patients with advanced stages of the disease.Sorafenib,the standard first-line therapy,faces significant challenges due to the development of drug resistance.Yu et al explored the mechanisms by which lncRNA KIF9-AS1 regulates the stemness and sorafenib resistance in HCC using a combination of cell culture,transfection,RNA immunoprecipitation,co-immunoprecipitation,and xenograft tumor models.They demonstrate that N6-methyladenosine-modified long non-coding RNA KIF9-AS1 acts as an oncogene in HCC.This modification involves methyltransferase-like 3 and insulin-like growth factor 2 mRNA-binding protein 1,which play critical roles in regulating KIF9-AS1.Furthermore,KIF9-AS1 stabilizes and upregulates short stature homeobox 2 by promoting its deubiquitination through ubiquitin-specific peptidase 1,thereby enhancing stemness and contributing to sorafenib resistance in HCC cells.These findings provide a theoretical basis for KIF9-AS1 as a diagnostic marker and therapeutic target for HCC,highlighting the need for further investigation into its clinical application potential. 展开更多
关键词 Hepatocellular carcinoma STEMNESS Sorafenib resistance long non-coding RNA KIF9-AS1 Short stature homeobox 2 N6-methyladenosine
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Load-measurement method for floating offshore wind turbines based on a long short-term memory (LSTM) neural network 被引量:1
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作者 Yonggang LIN Xiangheng FENG +1 位作者 Hongwei LIU Yong SUN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第5期456-470,共15页
Complicated loads encountered by floating offshore wind turbines(FOWTs)in real sea conditions are crucial for future optimization of design,but obtaining data on them directly poses a challenge.To address this issue,w... Complicated loads encountered by floating offshore wind turbines(FOWTs)in real sea conditions are crucial for future optimization of design,but obtaining data on them directly poses a challenge.To address this issue,we applied machine learning techniques to obtain hydrodynamic and aerodynamic loads of FOWTs by measuring platform motion responses and wave-elevation sequences.First,a computational fluid dynamics(CFD)simulation model of the floating platform was established based on the dynamic fluid body interaction technique and overset grid technology.Then,a long short-term memory(LSTM)neural network model was constructed and trained to learn the nonlinear relationship between the waves,platform-motion inputs,and hydrodynamic-load outputs.The optimal model was determined after analyzing the sensitivity of parameters such as sample characteristics,network layers,and neuron numbers.Subsequently,the effectiveness of the hydrodynamic load model was validated under different simulation conditions,and the aerodynamic load calculation was completed based on the D'Alembert principle.Finally,we built a hybrid-scale FOWT model,based on the software in the loop strategy,in which the wind turbine was replaced by an actuation system.Model tests were carried out in a wave basin and the results demonstrated that the root mean square errors of the hydrodynamic and aerodynamic load measurements were 4.20%and 10.68%,respectively. 展开更多
关键词 Floating offshore wind turbine(FOWT) long short-term memory(LSTM)neural network Machine learning technique Load measurement Hybrid-scale model test
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The well-posedness of incompressible impinging jet flow in an axisymmetric finitely long nozzle
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作者 WANG Xin ZHANG Fan 《四川大学学报(自然科学版)》 北大核心 2025年第1期31-37,共7页
This paper mainly studies the well-posedness of steady incompressible impinging jet flow problem through a 3D axisymmetric finitely long nozzle.This problem originates from the physical phenomena encountered in practi... This paper mainly studies the well-posedness of steady incompressible impinging jet flow problem through a 3D axisymmetric finitely long nozzle.This problem originates from the physical phenomena encountered in practical engineering fields,such as in short take-off and vertical landing(STOVL)aircraft.Nowadays many intricate phenomena associated with impinging jet flows remain inadequately elucidated,which limits the ability to optimize aircraft design.Given a boundary condition in the inlet,the impinging jet problem is transformed into a Bernoulli-type free boundary problem according to the stream function.Then the variational method is used to study the corresponding variational problem with one parameter,thereby the wellposedness is established.The main conclusion is as follows.For a 3D axisymmetric finitely long nozzle and an infinitely long vertical wall,given an axial velocity in the inlet of nozzle,there exists a unique smooth incom‑pressible impinging jet flow such that the free boundary initiates smoothly at the endpoint of the nozzle and extends to infinity along the vertical wall at far fields.The key point is to investigate the regularity of the corner where the nozzle and the vertical axis intersect. 展开更多
关键词 Existence and uniqueness Impinging jet flow Incompressible flow Free boundary Axisym-metric finitely long nozzle
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Optimizing Stock Market Prediction Using Long Short-Term Memory Networks
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作者 Nadia Afrin Ritu Samsun Nahar Khandakar +1 位作者 Md. Masum Bhuiyan Md. Imdadul Islam 《Journal of Computer and Communications》 2025年第2期207-222,共16页
Deep learning plays a vital role in real-life applications, for example object identification, human face recognition, speech recognition, biometrics identification, and short and long-term forecasting of data. The ma... Deep learning plays a vital role in real-life applications, for example object identification, human face recognition, speech recognition, biometrics identification, and short and long-term forecasting of data. The main objective of our work is to predict the market performance of the Dhaka Stock Exchange (DSE) on day closing price using different Deep Learning techniques. In this study, we have used the LSTM (Long Short-Term Memory) network to forecast the data of DSE for the convenience of shareholders. We have enforced LSTM networks to train data as well as forecast the future time series that has differentiated with test data. We have computed the Root Mean Square Error (RMSE) value to scrutinize the error between the forecasted value and test data that diminished the error by updating the LSTM networks. As a consequence of the renovation of the network, the LSTM network provides tremendous performance which outperformed the existing works to predict stock market prices. 展开更多
关键词 long Short-Term Memory (LSTM) Stock Market PREDICTION Time Series Analysis Deep Learning
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Nonlinear Resonance Response of Suspended Cables Under Multi-Frequency Excitations and Time-Delayed Feedback
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作者 Jian Peng Hui Xia +2 位作者 Lianhua Wang Xiaoyu Zhang Xianzhong Xie 《Acta Mechanica Solida Sinica》 2025年第4期689-700,共12页
This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for d... This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for detailed examination.Initially,utilizing Hamilton’s variational principle,a nonlinear vibration control model of suspended cables under multi-frequency excitations and longitudinal time-delayed velocity feedback is developed,and the Galerkin method is employed to obtain the discrete model.Subsequently,focusing solely on single-mode discretization,analytical solutions for the two simultaneous resonances are derived using the method of multiple scales.The frequency response equations are derived,and the stability analysis is presented for two simultaneous resonance cases.The results demonstrate that suspended cables exhibit complex nonlinearity under multi-frequency excitations.Multiple solutions under multi-frequency excitation can be distinguished through the frequency–response and the detuning-phase curves.By adjusting the control gain and time delay,the resonance range,response amplitude,and phase of suspended cables can be modified. 展开更多
关键词 Suspended cables Multi-frequency excitation time-delayed feedback Nonlinear resonance response
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Data-Driven Time-Delay Optimal Control Method for Roller Kiln Temperature Field
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作者 Jiayao Chen Weihua Gui +4 位作者 Ning Chen Biao Luo Binyan Li Zeng Luo Chunhua Yang 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1776-1787,共12页
In the industrial roller kiln,the time-delay characteristic in heat transfer causes the temperature field to be affected by both the current and historical temperature states.It presents a poor control performance and... In the industrial roller kiln,the time-delay characteristic in heat transfer causes the temperature field to be affected by both the current and historical temperature states.It presents a poor control performance and brings a significant challenge to the process precise control.Considering high complexity of precise modeling,a data-driven time-delay optimal control method for temperature field of roller kiln is proposed based on a large amount of process data.First,the control challenges and problem description brought by time-delay are demonstrated,where the cost function for the time-delay partial differential equation system is constructed.To obtain the optimal control law,the policy iteration in adaptive dynamic programming is adopted to design the time-delay temperature field controller,and neural network is used for the critic network in policy iteration to approximate the optimal time-delay cost function.The closed-loop system stability is proved by designing the Lyapunov function which contains the time-delay information.Finally,through establishing the time-delay temperature field model for roller kiln,the effectiveness and convergence of the proposed method is verified and proved. 展开更多
关键词 Distributed parameter system optimal control policy iteration roller kiln time-delay temperature field
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Vibration suppression analysis of iced transmission lines under axial time-delay velocity feedback strategy
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作者 Maoming Hu Guangyun Min +3 位作者 Wanyu Bao Bowen Tian Shuguang Yang Mengqi Cai 《Theoretical & Applied Mechanics Letters》 2025年第1期69-86,共18页
To ensure the safety of power energy transmission channel and mitigate the harm caused by galloping of iced transmission lines,the axial time-delay velocity feedback strategy is adopted to suppress the galloping.The p... To ensure the safety of power energy transmission channel and mitigate the harm caused by galloping of iced transmission lines,the axial time-delay velocity feedback strategy is adopted to suppress the galloping.The par-tial differential equation of galloping with axial time-delay velocity feedback strategy is established based on the variational principle for Hamiltonian.Then,the partial differential equation of galloping is transformed into or-dinary differential equation based on normalization and the Galerkin method.The primary amplitude-frequency response equation,the first-order steady-state approximate solution,and the harmonic amplitude-frequency re-sponse equation are derived by the multiscale method.The impact of different parameters such as time-delay value,control coefficient,and amplitude of external excitation on the galloping response are analyzed.The am-plitude under the primary resonance exhibits periodicity as time-delay value varies.The amplitude diminishes with increased control coefficient and increases with external excitation.Comprehensive consideration of vari-ous influences of parameters on vibration characteristics is crucial when employing the axial time-delay velocity feedback strategy to suppress galloping.Therefore,to achieve the best vibration suppression effect,it is crucial to adjust the time-delay parameter for modifying the range and amplitude of the resonance zone.The conclusions obtained by this study are expected to advance the refinement of active control techniques for iced transmission lines,and may provide valuable insights for practical engineering applications. 展开更多
关键词 Iced transmission lines Galloping characteristics Axial time-delay velocity feedback STRATEGY Primary resonance Harmonic resonance
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Chinese herbal medicine for dyspnea and persistent symptoms of long COVID:A systematic review and meta-analysis of randomized controlled trials
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作者 Miranda Sin-Man Tsang Iris Wenyu Zhou +1 位作者 Anthony Lin Zhang Charlie Changli Xue 《Journal of Integrative Medicine》 2025年第2期126-137,共12页
Background:Over 65 million people have long COVID.Evidence for using Chinese herbal medicine(CHM)to treat long COVID is growing.A systematic review of evidence for guiding clinical decision is warranted.Objective:To e... Background:Over 65 million people have long COVID.Evidence for using Chinese herbal medicine(CHM)to treat long COVID is growing.A systematic review of evidence for guiding clinical decision is warranted.Objective:To examine the effects and safety of CHM in alleviating the severity of dyspnea,fatigue,exercise intolerance,depression,anxiety and insomnia in long COVID adults based on registered randomized clinical trials(RCT).Search strategy:World Health Organization International Clinical Trials Registry Platform and Chinese Clinical Trial Registry were searched for registered trial protocols from database inception to February 10,2023.English(PubM ed,Embase,AMED and CINAHL)and Chinese databases(CNKI,Wanfang Data and CQVIP)were then searched to identify relevant publications from December 2019 through April 6,2023.Inclusion criteria:Registered RCTs that compared the effects of Chinese herbal medicines or Chinese herbal formulas against a control treatment(i.e.,the placebo or usual care)in adults with persistent symptoms of long COVID.The primary outcome of dyspnea,and secondary outcomes of fatigue,exercise intolerance,depression,anxiety and insomnia were measured using validated tools at the end of the treatment.Data extraction and analysis:Data were extracted,and eligible RCTs were evaluated using version 2 of the Cochrane risk-of-bias tool for randomized trials and Grading of Recommendations,Assessment,Development and Evaluations independently by two researchers.Effect sizes were estimated by randomeffects modelling and mean difference(MD).Heterogeneity between trials was quantified by I^(2).Results:Among the 38 registered clinical trials we identified,seven RCTs(1,519 patients)were included in the systematic review.One RCT had a low overall risk of bias.Compared to the control,CHM reduces dyspnea on the Borg Dyspnea Scale score(MD=–0.2,95%confidence interval[CI]=–0.65 to 0.25)with moderate certainty,and reduces fatigue on the Borg Scale(MD=–0.48,95%CI=–0.74 to–0.22)with low certainty.CHM clinically reduces depression on Hamilton Depression Rating Scale score(MD=–6.00,95%CI=–7.56 to–4.44)and anxiety on Hamilton Anxiety Rating Scale score(MD=–6.10,95%CI=–7.67 to–4.53),and reduces insomnia on the Insomnia Severity Index(MD=–4.86,95%CI=–12.50 to 2.79)with moderate certainty.Meta-analysis of two RCTs(517 patients)showed that CHM clinically improves exercise intolerance by increasing 6-minute walking distance(MD=–15.92,95%CI=–10.20 to 42.05)with substantial heterogeneity(I^(2)=68%)and low certainty.Conclusion:CHM is associated with a post-treatment clinical reduction in depression and anxiety in long COVID adults,compared to the control,but it does not have a strong treatment effect on dyspnea and insomnia.Effects of CHM on exercise intolerance and fatigue are uncertain,and the safety of using CHM remains questionable. 展开更多
关键词 long COVID DYSPNEA Chinese herbal medicine EFFECTIVENESS Safety
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