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Coherent feedback ground-state cooling of mechanical resonators assisted by a quantum well
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作者 Qinghong Liao Songyun Ouyang +1 位作者 Shaoping Cheng Yiping Cheng 《Chinese Physics B》 2025年第4期405-411,共7页
We theoretically investigate a cooling scheme assisted by a quantum well(QW)and coherent feedback within a hybrid optomechanical system.Although the exciton mode in the QW and the mechanical resonator(MR)are initially... We theoretically investigate a cooling scheme assisted by a quantum well(QW)and coherent feedback within a hybrid optomechanical system.Although the exciton mode in the QW and the mechanical resonator(MR)are initially uncoupled,their interaction via the microcavity field leads to an indirect exciton-mode–mechanical-mode coupling.The coherent feedback loop is applied by feeding back a fraction of the output field of the cavity through a controllable beam splitter to the cavity’s input mirror.It is shown that the cooling capability is enhanced by effectively suppressing the Stokes process through coupling with the QW.Furthermore,the effect of the anti-Stokes process is enhanced through the application of the coherent feedback loop.This particular system configuration enables cooling of the mechanical resonator even in the unresolved sideband regime(USR).This study has some important guiding significance in the field of quantum information processing. 展开更多
关键词 ground-state cooling quantum well coherent feedback optomechanical system
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A Study on Trainee Teachers’Stated Beliefs and Their Pedagogical Practices of Oral Corrective Feedback in the Chinese as a Second Language Classroom
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作者 Yang Yang 《Journal of Contemporary Educational Research》 2025年第3期102-117,共16页
The aim of the present study is to explore how native Chinese trainee teachers reflect on their usages of oral corrective feedback in class and what their actual teaching practices are in Chinese as a second language(... The aim of the present study is to explore how native Chinese trainee teachers reflect on their usages of oral corrective feedback in class and what their actual teaching practices are in Chinese as a second language(CSL)classroom.To this end,a mixed-methods approach was adopted in this study,including the questionnaire to explore teachers’perceptions as well as classroom observation to understand teachers’pedagogical practices during class.Fifteen trainee teachers from the same teacher training program in a university in China were identified and recruited to help complete the current research.The present study indicates that in the CSL context,teachers play an essential role in the language classroom and serve as the main resource of classroom feedback.When comparing trainee teachers’stated beliefs to their teaching practices,some similarities could be identified between them,however,clear divergence was also noticeable in the present study.Compared to the previous studies on oral corrective feedback in ESL and EFL contexts,most of the findings in the current study could correspond to those outcomes.The implication emphasizes the importance of offering more support to trainee teachers to help them deal with the complex classroom context such as through teacher training programs.Further investigations on students’perceptions of oral corrective feedback in class would also contribute to the understanding of oral corrective feedback in the CSL context. 展开更多
关键词 Oral corrective feedback Chinese as a second language Trainee teacher
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UHMK1 Promotes Prostate Cancer Progression through a Positive Feedback Loop with MTHFD2
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作者 Chi Zhang Xi Huang +7 位作者 Cheng Hu Bowen Tang Jianjie Wu Zhuolun Sun Weian Zhu Xiangfu Zhou Hengjun Xiao Hua Wang 《Oncology Research》 2025年第9期2331-2351,共21页
Background:U2AF homology motif kinase 1(UHMK1)has been associated with RNA processing and protein phosphorylation,thereby influencing tumor progression.The study aimed to explore its regulatory mechanisms and biologic... Background:U2AF homology motif kinase 1(UHMK1)has been associated with RNA processing and protein phosphorylation,thereby influencing tumor progression.The study aimed to explore its regulatory mechanisms and biological functions in human prostate cancer(PCa).Methods:In this study,we systematically evaluated the expression and prognostic significance of UHMK1 in public databases,followed by validation through immunohis-tochemistry(IHC)in PCa specimens.Both gain-of-function and loss-of-function experiments were conducted to elucidate the role of UHMK1 in vitro and in vivo.Additionally,a series of molecular and biochemical assays were performed to investigate the regulatory mechanisms underlying UHMK1 activity.Results:Our findings revealed that UHMK1 expression was significantly upregulated in PCa tissues and correlated with poor patient prognosis,as demonstrated by analysis of public datasets and confirmed by immunohistochemical staining.Functional studies showed that UHMK1 depletion suppressed tumor cell proliferation and metastasis,while its overexpression promoted these processes.Mechanistically,we identified that UHMK1 phosphorylates nuclear receptor coactivator 3(NCOA3),which subsequently activates activating transcription factor 4(ATF4)to upregulate methylenetetrahydrofolate dehy-drogenase 2(MTHFD2)transcription.Interestingly,MTHFD2 was found to reciprocally enhance UHMK1 expression,establishing a positive feedback loop.Conclusions:In conclusion,our data suggest that the UHMK1-MTHFD2 axis forms a positive feedback loop that drives PCa progression.Targeting this loop represents a promising therapeutic strategy for restraining prostate cancer development and progression. 展开更多
关键词 Cancer progression prostate cancer(PCa) positive feedback loop methylenetetrahydrofolate dehydrogenase 2(MTHFD2) U2AF Homology Motif Kinase 1(UHMK1)
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Pure State Feedback Switching Control Based on the Online Estimated State for Stochastic Open Quantum Systems
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作者 Shuang Cong Zhixiang Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2166-2178,共13页
For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SF... For the n-qubit stochastic open quantum systems,based on the Lyapunov stability theorem and LaSalle’s invariant set principle,a pure state switching control based on on-line estimated state feedback(short for OQST-SFC)is proposed to realize the state transition the pure state of the target state including eigenstate and superposition state.The proposed switching control consists of a constant control and a control law designed based on the Lyapunov method,in which the Lyapunov function is the state distance of the system.The constant control is used to drive the system state from an initial state to the convergence domain only containing the target state,and a Lyapunov-based control is used to make the state enter the convergence domain and then continue to converge to the target state.At the same time,the continuous weak measurement of quantum system and the quantum state tomography method based on the on-line alternating direction multiplier(QST-OADM)are used to obtain the system information and estimate the quantum state which is used as the input of the quantum system controller.Then,the pure state feedback switching control method based on the on-line estimated state feedback is realized in an n-qubit stochastic open quantum system.The complete derivation process of n-qubit QST-OADM algorithm is given;Through strict theoretical proof and analysis,the convergence conditions to ensure any initial state of the quantum system to converge the target pure state are given.The proposed control method is applied to a 2-qubit stochastic open quantum system for numerical simulation experiments.Four possible different position cases between the initial estimated state and that of the controlled system are studied and discussed,and the performances of the state transition under the corresponding cases are analyzed. 展开更多
关键词 Online state estimation state feedback control stochastic open quantum systems(OQST) switching control
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Enhanced adaptive nonlinear extended state observer for pure feedback systems with matched and mismatched disturbances
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作者 Mahtab Delpasand Mohammad Farrokhi 《Control Theory and Technology》 EI CSCD 2024年第2期254-268,共15页
In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a n... In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a nonlinear system with matched and mismatched disturbances is considered. The conventional extended state observer (ESO) can only be applied to systems that are in the form of integral chains. Moreover, this method has limitations in the face of mismatched disturbances. In the presence of time-varying disturbances, the traditional ESOs cannot estimate the disturbances accurately. To overcome this limitation, an EANESO is proposed in this paper. The main idea is to design the nonlinear ESO (NESO) to estimate the states of the system and multiple disturbances simultaneously. The observer gains are considered time-varying and adjusted with adaptation laws to improve the estimation accuracy and overcome the peaking phenomenon. Next, the proposed controller is designed based on output feedback to eliminate the effects of multiple disturbances and stabilize the closed-loop system. Subsequently, the stability analysis of the closed-loop system and convergence of the observer error are discussed. Finally, the proposed method is applied to the inverted pendulum system. The simulated results show good performance of the proposed method as compared with a recently published scheme in the related literature. 展开更多
关键词 Nonlinear extended state observer Enhanced adaptive extended state observer Adaptation law Multiple-channel disturbances Inverted pendulum system Time-varying gain
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Method for Estimating the State of Health of Lithium-ion Batteries Based on Differential Thermal Voltammetry and Sparrow Search Algorithm-Elman Neural Network 被引量:1
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作者 Yu Zhang Daoyu Zhang TiezhouWu 《Energy Engineering》 EI 2025年第1期203-220,共18页
Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,curr... Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,current SOH estimation methods often overlook the valuable temperature information that can effectively characterize battery aging during capacity degradation.Additionally,the Elman neural network,which is commonly employed for SOH estimation,exhibits several drawbacks,including slow training speed,a tendency to become trapped in local minima,and the initialization of weights and thresholds using pseudo-random numbers,leading to unstable model performance.To address these issues,this study addresses the challenge of precise and effective SOH detection by proposing a method for estimating the SOH of lithium-ion batteries based on differential thermal voltammetry(DTV)and an SSA-Elman neural network.Firstly,two health features(HFs)considering temperature factors and battery voltage are extracted fromthe differential thermal voltammetry curves and incremental capacity curves.Next,the Sparrow Search Algorithm(SSA)is employed to optimize the initial weights and thresholds of the Elman neural network,forming the SSA-Elman neural network model.To validate the performance,various neural networks,including the proposed SSA-Elman network,are tested using the Oxford battery aging dataset.The experimental results demonstrate that the method developed in this study achieves superior accuracy and robustness,with a mean absolute error(MAE)of less than 0.9%and a rootmean square error(RMSE)below 1.4%. 展开更多
关键词 Lithium-ion battery state of health differential thermal voltammetry Sparrow Search Algorithm
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Unifying Fixed Time and Prescribed Time Control for Strict-Feedback Nonlinear Systems
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作者 Xiang Chen Yujuan Wang Yongduan Song 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期347-355,共9页
This paper investigates the prescribed-time tracking control problem for a class of multi-input multi-output(MIMO)nonlinear strict-feedback systems subject to non-vanishing uncertainties. The inherent unmatched and no... This paper investigates the prescribed-time tracking control problem for a class of multi-input multi-output(MIMO)nonlinear strict-feedback systems subject to non-vanishing uncertainties. The inherent unmatched and non-vanishing uncertainties make the prescribed-time control problem become much more nontrivial. The solution to address the challenges mentioned above involves incorporating a prescribed-time filter, as opposed to a finite-time filter, and formulating a prescribed-time Lyapunov stability lemma(Lemma 5). The prescribed-time Lyapunov stability lemma is based on time axis shifting time-varying yet bounded gain, which establishes a novel link between the fixed-time and prescribed-time control method. This allows the restriction condition that the time-varying gain function must satisfy as imposed in most exist prescribed-time control works to be removed. Under the proposed control method, the desire trajectory is ensured to closely track the output of the system in prescribed time. The effectiveness of the theoretical results are verified through numerical simulation. 展开更多
关键词 Prescribed-time control prescribed-time filter robust control state feedback strict-feedback systems
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A Verification Theorem for Feedback Nash Equilibrium in Multiple-Player Nonzero-Sum Impulse Game 被引量:1
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作者 Ruihai Li Yaoyao Tan +1 位作者 Xiaojie Su Jiangshuai Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期648-650,共3页
Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate... Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate this impulse game problem with the modified objective function including interaction costs among the players in a discontinuous fashion,and subsequently,to derive a verification theorem for identifying the feedback Nash equilibrium strategy. 展开更多
关键词 impulse game feedback Nash equilibrium multiple player feedback nash equilibrium strategy impulse game problem nonzero sum modified objective function impulse controlsour
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An Empirical Study on the Reflective Feedback Model Based on Pedagogical Agents to Improve Students’ Problem-Solving Ability 被引量:1
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作者 Hui-Lin Zhang Jun-Jie Yan +4 位作者 Jing Liu Zhuo-Cen Zou Qun-Fang Zeng Yu-Lu Jin Jian-Nan Wu 《教育技术与创新》 2025年第1期66-75,共10页
This study constructs a reflective feedback model based on a pedagogical agent(PA)and explores its impact on students’problem-solving ability and cognitive load.A quasi-experimental design was used in the study,with ... This study constructs a reflective feedback model based on a pedagogical agent(PA)and explores its impact on students’problem-solving ability and cognitive load.A quasi-experimental design was used in the study,with 84 students from a middle school selected as the research subjects(44 in the experimental group and 40 in the control group).The experimental group used the reflective feedback model,while the control group used the factual feedback model.The results show that,compared with factual feedback,the reflective feedback model based on the pedagogical agent significantly improves students’problem-solving ability,especially at the action and thinking levels.In addition,this model effectively reduces students’cognitive load,especially in terms of internal and external load. 展开更多
关键词 pedagogical agent problem-solving ability reflective feedback
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Multi-hop quantum teleportation based on HSES via GHZ-like states 被引量:1
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作者 She-Xiang Jiang Xiao-Long Wei +1 位作者 Jin-Huan Li Shuai-Shuai Li 《Chinese Physics B》 2025年第1期60-70,共11页
Implementing quantum wireless multi-hop network communication is essential to improve the global quantum network system. In this paper, we employ eight-level GHZ states as quantum channels to realize multi-hop quantum... Implementing quantum wireless multi-hop network communication is essential to improve the global quantum network system. In this paper, we employ eight-level GHZ states as quantum channels to realize multi-hop quantum communication, and utilize the logical relationship between the measurements of each node to derive the unitary operation performed by the end node. The hierarchical simultaneous entanglement switching(HSES) method is adopted, resulting in a significant reduction in the consumption of classical information compared to multi-hop quantum teleportation(QT)based on general simultaneous entanglement switching(SES). In addition, the proposed protocol is simulated on the IBM Quantum Experiment platform(IBM QE). Then, the data obtained from the experiment are analyzed using quantum state tomography, which verifies the protocol's good fidelity and accuracy. Finally, by calculating fidelity, we analyze the impact of four different types of noise(phase-damping, amplitude-damping, phase-flip and bit-flip) in this protocol. 展开更多
关键词 multi-hop quantum teleportation GHZ-like state hierarchical simultaneous entanglement swapping IBM Quantum Experiment platform quantum state tomography
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Interpretation of the Pathological Mechanism of Blood Stasis in Traditional Chinese Medicine in Light of Understanding of Hypercoagulable States in Modern Medicine 被引量:2
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作者 Yong Chen Yujie Zhang 《Chinese Medicine and Natural Products》 2025年第1期30-34,共5页
In both Traditional Chinese Medicine(TCM)and modern medicine,they agree that the integrity and healthy structure of the vascular endothelium are essential for normal hemodynamics.Damage to the vascular endothelium can... In both Traditional Chinese Medicine(TCM)and modern medicine,they agree that the integrity and healthy structure of the vascular endothelium are essential for normal hemodynamics.Damage to the vascular endothelium can quickly activate the extrinsic coagulation pathway by triggering the tissue factor(TF)and lead to coagulation.This damage,along with a loss of anticoagulant properties through antithrombinⅢ(ATⅢ),TF pathway inhibitors,and the protein C system,can result in a hypercoagulable state and even thrombosis.Hypercoagulability is not only a common feature of many cancers but also an important factor promoting tumor development and metastasis,which corresponds to the TCM theory of“blood stasis leading to tumors.”The pharmacological effects of heparin and aspirin have similarities with TCM's“activating blood circulation and removing blood stasis”theory in improving blood circulation,treating related diseases,and their anti-inflammatory effects. 展开更多
关键词 blood stasis hypercoagulable state THROMBOSIS HEPARIN aspirin Traditional Chinese Medicine modern medicine
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Prediction of microstructure evolution of ZK61 alloy during hot spinning by internal state variable model 被引量:2
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作者 Jin-qi PAN Wen-cong ZHANG +3 位作者 Jian-lei YANG Song-hui WANG Yong WU Huan LI 《Transactions of Nonferrous Metals Society of China》 2025年第1期126-142,共17页
An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of t... An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of the internal variables were considered in this ISV model,and the parameters were optimized by genetic algorithm.After validation,the ISV model was used to simulate the evolution of grain size(GS)and dynamic recrystallization(DRX)fraction during hot spinning via Abaqus and its subroutine Vumat.By comparing the simulated results with the experimental results,the application of the ISV model was proven to be reliable.Meanwhile,the strength of the thin-walled spun ZK61 tube increased from 303 to 334 MPa due to grain refinement by DRX and texture strengthening.Besides,some ultrafine grains(0.5μm)that played an important role in mechanical properties were formed due to the proliferation,movement,and entanglement of dislocations during the spinning process. 展开更多
关键词 internal state variable model hot spinning ZK61 alloy finite element simulation texture evolution
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High ductility induced by twin-assisted grain rotation and merging in solid-state cold spray additive manufactured Cu 被引量:1
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作者 Wenya Li Jingwen Yang +2 位作者 Zhengmao Zhang Yingchun Xie Chunjie Huang 《Journal of Materials Science & Technology》 2025年第11期11-15,共5页
1.Introduction.Cold Spray(CS)is a highly advanced solid-state metal depo-sition process that was first developed in the 1980s.This innovative technique involves the high-speed(300-1200 m/s)impact deposition of micron-... 1.Introduction.Cold Spray(CS)is a highly advanced solid-state metal depo-sition process that was first developed in the 1980s.This innovative technique involves the high-speed(300-1200 m/s)impact deposition of micron-sized particles(5-50μm)to fabricate coatings[1-3].CS has been extensively used in a variety of coating applications,such as aerospace,automotive,energy,medical,marine,and others,to provide protection against high temperatures,corrosion,erosion,oxidation,and chemicals[4,5].Nowadays,the technical interest in CS is twofold:(i)as a repair process for damaged components,and(ii)as a solid-state additive manufacturing process.Compared to other fusion-based additive manufacturing(AM)technologies,Cold Spray Additive Manufacturing(CSAM)is a new member of the AM family that can enable the fabrication of deposits without undergoing melting.The chemical composition has been largely preserved from the powder to the deposit due to the minimal oxidation.The significant advantages of CSAM over other additive manufacturing processes include a high production rate,unlimited deposition size,high flexibility,and suitability for repairing damaged parts. 展开更多
关键词 additive manufacturing DUCTILITY cold spray MERGING solid state deposition twin assisted grain rotation
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Effects of plasma screening on the^(1)P^(o)(n=3,n=4)resonance states of H-and He using the stabilization method
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作者 仲子鑫 吕柄宽 +2 位作者 姜子实 KAR Sabyasachi HO Yew Kam 《黑龙江大学自然科学学报》 2025年第4期469-487,共19页
The effects of plasma screening on the ^(1)P^(o) resonance states of H-and He below the n=3 and n=4 thresholds of the respective subsystemsare investigated using the stabilization method and correlated exponential wav... The effects of plasma screening on the ^(1)P^(o) resonance states of H-and He below the n=3 and n=4 thresholds of the respective subsystemsare investigated using the stabilization method and correlated exponential wave functions.Two plasma mediums,namely,the Debye plasma and quantum plasma environments are considered.The screened Coulomb potential(SCP)obtained from Debye-Hückel model is used to represent Debye plasma environments and the exponential cosine screened Coulomb potential(ECSCP)obtained from a modified Debye-Hückel model is used to represent quantum plasma environments.The resonance parameters(resonance positions and widths)are presented in terms of the screening parameters. 展开更多
关键词 quantum plasma Debye plasma P-wave resonance states correlated exponential wave functions stabilization method
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Hydrodynamic Performance and Structural Response of a Sharp Eagle Wave Energy Converter Platform Under Extreme Sea States 被引量:1
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作者 YUE Wan-zhen WANG Kun-lin +4 位作者 JIANG Jia-qiang SHENG Song-wei LU Wen-zhao HE Teng YANG Xian-yuan 《China Ocean Engineering》 2025年第2期373-382,共10页
This paper presents a new type of triangular Sharp Eagle wave energy converter(WEC)platform.On the basis of the linear potential flow theory and the finite element analysis method,the hydrodynamic performance and stru... This paper presents a new type of triangular Sharp Eagle wave energy converter(WEC)platform.On the basis of the linear potential flow theory and the finite element analysis method,the hydrodynamic performance and structural response of the platform are studied,considering the actual platform motion and free surface rise under extreme sea states.First,the effects of the wave frequency and direction on the wave-induced loads and dynamic responses were examined.The motion at a wave direction angle of 0°is relatively low.On this basis,the angle constrained by the two sides of the Sharp Eagle floaters should be aligned with the main wave direction to avoid significant platform motion under extreme sea states.Additionally,the structural response of the platform,including the wave-absorbing floaters,is investigated.The results highlighted that the conditions or locations where yielding,buckling,and fatigue failures occur were different.In this context,the connection area of the Sharp Eagle floaters and platform is prone to yielding failure under oblique wave action,whereas the pontoon and side of the Sharp Eagle floaters are prone to buckling failure during significant vertical motion.Additionally,fatigue damage is most likely to occur at the connection between the middle column on both sides of the Sharp Eagle floaters and the pontoons.The findings of this paper revealed an intrinsic connection between wave-induced loads and the dynamic and structural responses of the platform,which provides a useful reference for the improved design of WECs. 展开更多
关键词 wave energy converter extreme sea states finite element analysis dynamic response structural response
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A Research on Written Feedback in English Writing Course of English Majors
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作者 LIU Jun 《Sino-US English Teaching》 2025年第3期87-91,共5页
Written feedback in English writing classes serves as the primary mode of feedback.By comparing direct corrective feedback and indirect corrective feedback in addressing content and form,this paper argues that indirec... Written feedback in English writing classes serves as the primary mode of feedback.By comparing direct corrective feedback and indirect corrective feedback in addressing content and form,this paper argues that indirect corrective feedback better aligns with the needs of English majors.Multiple factors influence the choice of written feedback methods,and teachers should carefully select the most appropriate approach based on student characteristics to maximize the effectiveness of feedback. 展开更多
关键词 English writing written feedback indirect feedback corrective feedback
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The Efficacy of Written Corrective Feedback Explicitness on the Grammatical Accuracy of Passive Voice Tenses
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作者 Syed Muhammad Mujtaba Manjet Kaur Mehar Singh 《Chinese Journal of Applied Linguistics》 2025年第2期183-206,320,共25页
Although substantial research shows the effectiveness of written corrective feedback(WCF)in treating simple grammar structures,more research is still needed to refute Truscott’s claim that WCF may not work on complex... Although substantial research shows the effectiveness of written corrective feedback(WCF)in treating simple grammar structures,more research is still needed to refute Truscott’s claim that WCF may not work on complex grammar structures.Similarly,a previous body of research has shown that the degree of explicitness of feedback moderates the efficacy of WCF.However,most WCF studies have systematically manipulated only direct corrective feedback.The current study was therefore conducted to fill these gaps in the literature.To this end,five intact classes of Functional English were recruited and later randomly assigned to four treatment groups:DCF,DCF+ME,ICF,and ICF+ME,and one control group that received no feedback.All the groups took part in three WCF treatment sessions,during which they wrote two different pieces:a news report and a picture description.Later,only the treatment groups received the WCF.The WCF’s effectiveness was measured by writing tests and grammaticality judgment tasks(GJT).The results demonstrated that WCF helped L2 learners improve their grammatical accuracy of passive voice tenses.The study further showed that the group that received the most explicit type of WCF fared better than the ones that received the least explicit type of WCF.Important pedagogical implications for ESL/EFL teachers are discussed. 展开更多
关键词 written corrective feedback direct corrective feedback indirect corrective feedback metalinguistic explanation passive voice
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The Effect of Ultrasound Scanning on the State Anxiety among Expectant Mothers in Their First Trimester and Predictors of Anxiety
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作者 Navodya Weerasinghe Oshadee Kaushalya De Silva Senapathige Nilan Kalidasa Rodrigo 《Open Journal of Obstetrics and Gynecology》 2025年第1期167-189,共23页
Background: Undergoing ultrasound scanning (USS) during the first trimester of pregnancy is highly imperative for expecting mothers, as it supports the early detection of any malformations, identifying the fetal numbe... Background: Undergoing ultrasound scanning (USS) during the first trimester of pregnancy is highly imperative for expecting mothers, as it supports the early detection of any malformations, identifying the fetal number, fetal growth, fetal sex, and calculation of delivery. Previous studies have shown that undergoing such prenatal screening procedures could reduce the antenatal anxiety levels of expectant mothers. The present study aimed to explore the impact of first-trimester ultrasound scanning towards the antenatal anxiety and identify the predictors of antenatal anxiety among expectant mothers in the first trimester. Methods: A repeated measure design study was conducted in Maternity Clinics of University Hospital KDU, Ninewells Care Hospital and Navy General Hospital over 4 months with one hundred and fifteen (n = 115) expectant mothers. Participants completed a general information sheet first and State Trait Anxiety Inventory (STAI) (Spielberger et al., 1970) was administered before and after undergoing the USS. Results: Mean age of the participants was 28.84 ± 3.68. The Wilcoxon Signed Rank test showed that there is a significant reduction of participants’ antenatal anxiety levels following the USS z = −5.658, p Conclusions: Findings suggest that undergoing the first trimester USS significantly reduces the antenatal state anxiety and partner’s support is an important factor in reducing the antenatal anxiety experienced by expectant mothers in the first trimester. Future studies can focus on how USS can contribute to alleviating antenatal anxiety in second and third trimesters. 展开更多
关键词 Antenatal Anxiety state Anxiety First Trimester ULTRASOUND PREGNANCY
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Independent dual-band bound states in the continuum based on terahertz all-dielectric metasurfaces
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作者 WANG Yu LIU Yang +5 位作者 HAO Xiao-yu ZHENG Si-yu LIU Meng ZHANG Yu-ping ZHAN Yi ZHANG Hui-yun 《中国光学(中英文)》 北大核心 2025年第5期1230-1242,共13页
Compared to traditional single-frequency bound states in the continuum(BIC),dual-band BIC of-fers higher degrees of freedom and functionality.Moveover,implementing independent control of dual-band BICs can further enh... Compared to traditional single-frequency bound states in the continuum(BIC),dual-band BIC of-fers higher degrees of freedom and functionality.Moveover,implementing independent control of dual-band BICs can further enhance their advantages and maximize their performance.This study presents a design for a dielectric metasurface that achieves dual-band BICs in the terahertz(THz)range.By adjusting two asym-metry parameters of the structure,independent control of the two symmetry-protected BICs is achieved.Fur-thermore,by varying the shape of the silicon holes,the design's robustness to geometric variations is demon-strated.Finally,the test results show that the figures of merit(FOMs)for both BICs reach 109.This work provides a new approach for realizing and tuning dual-frequency BICs,offering expanded possibilities for applications in multimode lasers,nonlinear optics,multi-channel filtering,and optical sensing. 展开更多
关键词 dual-band bound states in the continuum metasurface terahertz sensing symmetry protection
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GHZ state,spin squeezed state,and spin coherent state for frequency estimation under general Gaussian noises
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作者 Qi Chai Wen Yang 《Communications in Theoretical Physics》 2025年第6期102-111,共10页
Exploring the quantum advantages of various non-classical quantum states in noisy environments is a central subject in quantum sensing.Here we provide a complete picture for the frequency estimation precision of three... Exploring the quantum advantages of various non-classical quantum states in noisy environments is a central subject in quantum sensing.Here we provide a complete picture for the frequency estimation precision of three important states(the Greenberger-Horne-Zeilinger(GHZ)state,the maximal spin squeezed state,and the spin coherent state)of a spin-S under both individual dephasing and collective dephasing by general Gaussian noise,ranging from the Markovian limit to the extreme non-Markovian limit.Whether or not the noise is Markovian,the spin coherent state is always worse than the classical scheme under collective dephasing although it is equivalent to the classical scheme under individual dephasing.Moreover,the maximal spin squeezed state always give the best sensing precision(and outperforms the widely studied GHZ state)in all cases.This establishes the general advantage of the spin squeezed state for noisy frequency estimation in many quantum sensing platforms. 展开更多
关键词 cat state spin squeezed state spin coherent state quantum sensing
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