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“Passive Program”的中文译名
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作者 王波 《大学图书情报学刊》 2026年第2期3-8,共6页
文章探讨了美国图书馆“Passive Program”的中文翻译问题。针对范并思教授的提问,文章指出将“Passive Program”译为“被动活动”不适合中文语境,因其带有消极色彩且未能准确反映这类活动所具有的图书馆员前期主动策划、过程中低干预... 文章探讨了美国图书馆“Passive Program”的中文翻译问题。针对范并思教授的提问,文章指出将“Passive Program”译为“被动活动”不适合中文语境,因其带有消极色彩且未能准确反映这类活动所具有的图书馆员前期主动策划、过程中低干预的核心特征。在分析得出“Passive Program”依靠空间与道具引导读者自发参与的特点后,作者提出将其转译为“造境阅读推广活动”,意指图书馆通过营造特定场景、情景或意境,激发读者自主阅读。“造境阅读推广活动”这个译名既契合“Passive Program”的内涵,又统摄了中美图书馆的同类实践,为理论研究、实践应用与中外交流提供了恰当的概念工具。 展开更多
关键词 Passive program 被动活动 造境阅读推广活动 场景阅读推广活动 情景阅读推广活动 意境阅读推广活动 美国图书馆
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Bearing capacity prediction of open caissons in two-layered clays using five tree-based machine learning algorithms 被引量:2
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作者 Rungroad Suppakul Kongtawan Sangjinda +3 位作者 Wittaya Jitchaijaroen Natakorn Phuksuksakul Suraparb Keawsawasvong Peem Nuaklong 《Intelligent Geoengineering》 2025年第2期55-65,共11页
Open caissons are widely used in foundation engineering because of their load-bearing efficiency and adaptability in diverse soil conditions.However,accurately predicting their undrained bearing capacity in layered so... Open caissons are widely used in foundation engineering because of their load-bearing efficiency and adaptability in diverse soil conditions.However,accurately predicting their undrained bearing capacity in layered soils remains a complex challenge.This study presents a novel application of five ensemble machine(ML)algorithms-random forest(RF),gradient boosting machine(GBM),extreme gradient boosting(XGBoost),adaptive boosting(AdaBoost),and categorical boosting(CatBoost)-to predict the undrained bearing capacity factor(Nc)of circular open caissons embedded in two-layered clay on the basis of results from finite element limit analysis(FELA).The input dataset consists of 1188 numerical simulations using the Tresca failure criterion,varying in geometrical and soil parameters.The FELA was performed via OptumG2 software with adaptive meshing techniques and verified against existing benchmark studies.The ML models were trained on 70% of the dataset and tested on the remaining 30%.Their performance was evaluated using six statistical metrics:coefficient of determination(R²),mean absolute error(MAE),root mean squared error(RMSE),index of scatter(IOS),RMSE-to-standard deviation ratio(RSR),and variance explained factor(VAF).The results indicate that all the models achieved high accuracy,with R²values exceeding 97.6%and RMSE values below 0.02.Among them,AdaBoost and CatBoost consistently outperformed the other methods across both the training and testing datasets,demonstrating superior generalizability and robustness.The proposed ML framework offers an efficient,accurate,and data-driven alternative to traditional methods for estimating caisson capacity in stratified soils.This approach can aid in reducing computational costs while improving reliability in the early stages of foundation design. 展开更多
关键词 two-layered clay Open caisson Tree-based algorithms FELA Machine learning
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Pitch Motion Analysis of a Submerged Cylindrical Structure in a Two-layer Fluid
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作者 Champak Kr.Neog Mohammad Hassan 《哈尔滨工程大学学报(英文版)》 2025年第5期984-997,共14页
This study investigates the effects of radiation force due to the rotational pitch motion of a wave energy device,which comprises a coaxial bottom-mounted cylindrical caisson in a two-layer fluid,along with a submerge... This study investigates the effects of radiation force due to the rotational pitch motion of a wave energy device,which comprises a coaxial bottom-mounted cylindrical caisson in a two-layer fluid,along with a submerged cylindrical buoy.The system is modeled as a two-layer fluid with infinite horizontal extent and finite depth.The radiation problem is analyzed in the context of linear water waves.The fluid domain is divided into outer and inner zones,and mathematical solutions for the pitch radiating potential are derived for the corresponding boundary valve problem in these zones using the separation of variables approach.Using the matching eigenfunction expansion method,the unknown coefficients in the analytical expression of the radiation potentials are evaluated.The resulting radiation potential is then used to compute the added mass and damping coefficients.Several numerical results for the added mass and damping coefficients are investigated for numerous parameters,particularly the effects of the cylinder radius,the draft of the submerged cylinder,and the density proportion between the two fluid layers across different frequency ranges.The major findings are presented and discussed. 展开更多
关键词 Pitch radiation Eigenfunction expansion two-layer Hydrodynamic coefficients Submerged cylinder Bottom-mounted cylinder
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A Two-Layer Network Intrusion Detection Method Incorporating LSTM and Stacking Ensemble Learning
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作者 Jun Wang Chaoren Ge +4 位作者 Yihong Li Huimin Zhao Qiang Fu Kerang Cao Hoekyung Jung 《Computers, Materials & Continua》 2025年第6期5129-5153,共25页
Network Intrusion Detection System(NIDS)detection of minority class attacks is always a difficult task when dealing with attacks in complex network environments.To improve the detection capability of minority-class at... Network Intrusion Detection System(NIDS)detection of minority class attacks is always a difficult task when dealing with attacks in complex network environments.To improve the detection capability of minority-class attacks,this study proposes an intrusion detection method based on a two-layer structure.The first layer employs a CNN-BiLSTM model incorporating an attention mechanism to classify network traffic into normal traffic,majority class attacks,and merged minority class attacks.The second layer further segments the minority class attacks through Stacking ensemble learning.The datasets are selected from the generic network dataset CIC-IDS2017,NSL-KDD,and the industrial network dataset Mississippi Gas Pipeline dataset to enhance the generalization and practical applicability of the model.Experimental results show that the proposed model achieves an overall detection accuracy of 99%,99%,and 95%on the CIC-IDS2017,NSL-KDD,and industrial network datasets,respectively.It also significantly outperforms traditional methods in terms of detection accuracy and recall rate for minority class attacks.Compared with the single-layer deep learning model,the two-layer structure effectively reduces the false alarm rate while improving the minority-class attack detection performance.The research in this paper not only improves the adaptability of NIDS to complex network environments but also provides a new solution for minority-class attack detection in industrial network security. 展开更多
关键词 two-layer architecture minority class attack stacking ensemble learning network intrusion detection
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Early cancer diagnosis via interpretable two-layer machine learning of plasma extracellular vesicle long RNA
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作者 Shi-Cai Liu Han Zhang 《World Journal of Gastrointestinal Oncology》 2025年第11期254-277,共24页
BACKGROUND The early diagnosis rate of pancreatic ductal adenocarcinoma(PDAC)is low and the prognosis is poor.It is important to develop an interpretable noninvasive early diagnostic model in clinical practice.AIM To ... BACKGROUND The early diagnosis rate of pancreatic ductal adenocarcinoma(PDAC)is low and the prognosis is poor.It is important to develop an interpretable noninvasive early diagnostic model in clinical practice.AIM To develop an interpretable noninvasive early diagnostic model for PDAC using plasma extracellular vesicle long RNA(EvlRNA).METHODS The diagnostic model was constructed based on plasma EvlRNA data.During the process of establishing the model,EvlRNA-index was introduced,and four algorithms were adopted to calculate EvlRNA-index.After the model was successfully constructed,performance evaluation was conducted.A series of bioinformatics methods were adopted to explore the potential mechanism of EvlRNA-index as the input feature of the model.And the relationship between key characteristics and PDAC were explored at the single-cell level.RESULTS A novel interpretable machine learning framework was developed based on plasma EvlRNA.In this framework,a two-layer classifier was established.A new concept was proposed:EvlRNA-index.Based on EvlRNA-index,a cancer diagnostic model was established,and a good diagnostic effect was achieved.The accuracy of PDACandCPvsHealth-Probabilistic PCA Index-SVM(PDAC and chronic pancreatitis vs health-probabilistic principal component analysis index-support vector machine)(1-18)was 91.51%,with Mathew’s correlation coefficient 0.7760 and area under the curve 0.9560.In the second layer of the model,the accuracy of PDACvsCP-Probabilistic PCA Index-RF(PDAC vs chronic pancreatitis-probabilistic principal component analysis index-random forest)(2-17)was 93.83%,with Mathew’s correlation coefficient 0.8422 and area under the curve 0.9698.Forty-nine PDAC-related genes were identified,among which 16 were known,inferring that the remaining ones were also PDAC-related genes.CONCLUSION An interpretable two-layer machine learning framework was proposed for early diagnosis and prediction of PDAC based on plasma EvlRNA,providing new insights into the clinical value of EvlRNA. 展开更多
关键词 Pancreatic ductal adenocarcinoma Extracellular vesicle long RNA Noninvasive early diagnosis Interpretable machine learning two-layer classifier
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A Two-Layer UAV Cooperative Computing Offloading Strategy Based on Deep Reinforcement Learning
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作者 Zhang Jianfei Wang Zhen +1 位作者 Hu Yun Chang Zheng 《China Communications》 2025年第10期251-268,共18页
In the wake of major natural disasters or human-made disasters,the communication infrastruc-ture within disaster-stricken areas is frequently dam-aged.Unmanned aerial vehicles(UAVs),thanks to their merits such as rapi... In the wake of major natural disasters or human-made disasters,the communication infrastruc-ture within disaster-stricken areas is frequently dam-aged.Unmanned aerial vehicles(UAVs),thanks to their merits such as rapid deployment and high mobil-ity,are commonly regarded as an ideal option for con-structing temporary communication networks.Con-sidering the limited computing capability and battery power of UAVs,this paper proposes a two-layer UAV cooperative computing offloading strategy for emer-gency disaster relief scenarios.The multi-agent twin delayed deep deterministic policy gradient(MATD3)algorithm integrated with prioritized experience replay(PER)is utilized to jointly optimize the scheduling strategies of UAVs,task offloading ratios,and their mobility,aiming to diminish the energy consumption and delay of the system to the minimum.In order to address the aforementioned non-convex optimiza-tion issue,a Markov decision process(MDP)has been established.The results of simulation experiments demonstrate that,compared with the other four base-line algorithms,the algorithm introduced in this paper exhibits better convergence performance,verifying its feasibility and efficacy. 展开更多
关键词 cooperative computational offloading deep reinforcement learning mobile edge computing prioritized experience replay two-layer unmanned aerial vehicles
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Reprogramming induced neurons from olfactory ensheathing glial cells: A feasible approach for spinal cord injury repair
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作者 Javier Sierra María Portela-Lomba +1 位作者 Diana Simón M.Teresa Moreno-Flores 《Neural Regeneration Research》 2026年第1期296-297,共2页
Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disruptin... Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disrupting the neural connections that allow communication between the brain and the rest of the body, which results in varying degrees of motor and sensory impairment. Disconnection in the spinal tracts is an irreversible condition owing to the poor capacity for spontaneous axonal regeneration in the affected neurons. 展开更多
关键词 INJURY feasible programMING
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Effectiveness of a stepped self-care program for stroke survivors:A quasi-experimental study
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作者 Zihao Ruan Dan Wang +5 位作者 Wenna Wang Yongxia Mei Hui Wang Suyan Chen Qiushi Zhang Zhenxiang Zhang 《International Journal of Nursing Sciences》 2026年第1期45-52,I0004,共9页
Objectives This study aimed to evaluate the effectiveness of the stepped self-care program on the self-care,self-efficacy,and quality of life of stroke survivors.Methods This quasi-experimental study allocated 110 str... Objectives This study aimed to evaluate the effectiveness of the stepped self-care program on the self-care,self-efficacy,and quality of life of stroke survivors.Methods This quasi-experimental study allocated 110 stroke survivors from two neurology wards into an intervention group(n=55)who received the stepped self-care program and a control group(n=55)who received usual care from June to December 2023.The Self-Care of Stroke Inventory,Stroke Self-Efficacy Questionnaire,and the short version of the Stroke Specific Quality of Life Scale were administered at baseline(T0),immediately post-intervention(T_(1)),and at 1-month(T_(2))and 3-month(T_(3))follow-ups.Data were analyzed using repeated measures analyses of variance,and generalized estimating equations.Results A total of 48 participants in the intervention group and 50 participants in the control group completed the study.No statistically significant differences were observed at T0 in any of the measured indicators(all P>0.05).The study showed significant group,time,and group×time interaction effects across the assessed outcomes(all P<0.05).Follow-up between-group comparisons at T_(1),T_(2),and T_(3) indicated that the intervention group had significantly higher scores in self-care maintenance,self-care monitoring,self-care management,self-efficacy,and quality of life than the control group(all P<0.001).Conclusions The stepped self-care program significantly improved self-care behaviors,self-efficacy,and quality of life among stroke survivors.These findings support the broader implementation of this approach in post-discharge home self-care. 展开更多
关键词 Quality of life SELF-CARE SELF-EFFICACY Stepped care program STROKE
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CD44-targeting and ZIF-8 gated gold nanocage for programmed breast cancer therapy through Pt-induced immunogenic cell death
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作者 Xin Li Fei Xiong +7 位作者 Xudong Cao Wei Liu Haobo Chen Jiayu He Weina Zhang Longguang Tang Wei Huang Xikuang Yao 《Chinese Chemical Letters》 2026年第1期462-467,共6页
The field of nanomedicine has been revolutionized by the concept of immunogenic cell death(ICD)-enhanced cancer therapy,which holds immense promise for the efficient treatment of cancer.However,precise delivery of ICD... The field of nanomedicine has been revolutionized by the concept of immunogenic cell death(ICD)-enhanced cancer therapy,which holds immense promise for the efficient treatment of cancer.However,precise delivery of ICD inducer is severely hindered by complex biological barriers.How to design and build intelligent nanoplatform for adaptive and dynamic cancer therapy remains a big challenge.Herein,this article presents the design and preparation of CD44-targeting and ZIF-8 gated gold nanocage(Au@ZH) for programmed delivery of the 1,2-diaminocyclohexane-Pt(Ⅱ)(DACHPt) as ICD inducer.After actively targeting the CD44 on the surface of 4T1 tumor cell,this Pt-Au@ZH can be effectively endocytosed by the 4T1 cell and release the DACHPt in tumor acidic environment,resulting in ICD effect and superior antitumor efficacy both in vitro and in vivo in the presence of mild 808 nm laser irradiation.By integration of internal and external stimuli intelligently,this programmed nanoplatform is poised to become a cornerstone in the pursuit of effective and targeted cancer therapy in the foreseeable future. 展开更多
关键词 programmed drug release ZIF-8-gated Gold nanocage Immunogenic cell death Cancer therapy
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Quality-guaranteed Dubins Path Planning for USV Based on Mixed-integer Piecewise linear Programming for Addressing the Extended Minimum-time Intercept Problem
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作者 Xing Zhou Kelin Zhu +3 位作者 Shuang Liu Zhaoqing Li Wenxin Zhang Kang Du 《哈尔滨工程大学学报(英文版)》 2026年第1期216-227,共12页
During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive... During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive distance)to a moving target as quickly as possible,resulting in the extended minimum-time intercept problem(EMTIP).Existing research has primarily focused on the zero-distance intercept problem,MTIP,establishing the necessary or sufficient conditions for MTIP optimality,and utilizing analytic algorithms,such as root-finding algorithms,to calculate the optimal solutions.However,these approaches depend heavily on the properties of the analytic algorithm,making them inapplicable when problem settings change,such as in the case of a positive effective range or complicated target motions outside uniform rectilinear motion.In this study,an approach employing a high-accuracy and quality-guaranteed mixed-integer piecewise-linear program(QG-PWL)is proposed for the EMTIP.This program can accommodate different effective interception ranges and complicated target motions(variable velocity or complicated trajectories).The high accuracy and quality guarantees of QG-PWL originate from elegant strategies such as piecewise linearization and other developed operation strategies.The approximate error in the intercept path length is proved to be bounded to h^(2)/(4√2),where h is the piecewise length. 展开更多
关键词 Minimum-time intercept problem Dubins vehicle Mixed-integer piecewise-linear program LINEARIZATION Approximate error trigonometric function USV
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African Mothers'New Farms Program Cultivates Women's Strength to Boost Agriculture,Livelihood
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作者 Ye Shan 《Women of China》 2026年第3期44-47,共4页
Editor's Note In his keynote address at the opening ceremony of the Global Leaders'Meeting on Women,held in Beijing on October 13,2025,Chinese President Xi Jinping announced a series of measures China will tak... Editor's Note In his keynote address at the opening ceremony of the Global Leaders'Meeting on Women,held in Beijing on October 13,2025,Chinese President Xi Jinping announced a series of measures China will take,in the next five years,to further support the global cause of women.One of the measures is:China will launch 1,000"small and beautiful"livelihood programs with Chinese assistance that take women and girls as priority beneficiaries. 展开更多
关键词 new farms program LIVELIHOOD WOMEN African mothers womens strength global leaders meeting AGRICULTURE chinese assistance
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Joint inversion of gravity and magnetic data for a two-layer model 被引量:2
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作者 江凡 吴健生 王家林 《Applied Geophysics》 SCIE CSCD 2008年第4期331-339,共9页
Based on the synchronous joint gravity and magnetic inversion of single interface by Pilkington and the need of revealing Cenozoic and crystalline basement thickness in the new round of oil-gas exploration, we propose... Based on the synchronous joint gravity and magnetic inversion of single interface by Pilkington and the need of revealing Cenozoic and crystalline basement thickness in the new round of oil-gas exploration, we propose a joint gravity and magnetic inversion methodfor two-layer models by concentrating on the relationship between the change of thicknessI and position of the middle layer and anomaly and discuss the effects of the key parameters. Model tests and application to field data show the validity of this method. 展开更多
关键词 two-layer model joint inversion of gravity and magnetic data Cenozoic andcrystalline basement
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Effective Moduli of Two-Layered Spherical Inclusions Reinforced Composites
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作者 胡更开 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期59-66,共8页
A model is proposed to evaluate the,effective modufi of a composite reinforced by two-layered spherical inclusions.This model is based on the localisation problem of a two- layered spherical inclusion embedded in an i... A model is proposed to evaluate the,effective modufi of a composite reinforced by two-layered spherical inclusions.This model is based on the localisation problem of a two- layered spherical inclusion embedded in an infinite matrix.The interations of the reinforced phases are taken into account by using the average matrix stress concept.When the external layer vanishes,the proposed model reduces to the classical Mori-Tanaka's model for spherical inclusions.Theoretical results for the composite of polyester matrix filled by hollow glass spheres and voids show excellent agreement with experimental results. 展开更多
关键词 two-layered spherical inclusion effective moduli COMPOSITE MICROMECHANICS
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Geo-engineered buffer capacity of two-layered absorbing system under the impact of rock avalanches based on Discrete Element Method 被引量:15
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作者 BI Yu-zhang HE Si-ming +5 位作者 LI Xin-po WU Yong XU Qiang OUYANG Chao-jun SU Li-Jun WANG Hao 《Journal of Mountain Science》 SCIE CSCD 2016年第5期917-929,共13页
Many rock avalanches were triggered by the Wenchuan earthquake on May 12, 2008 in southwest China. Protection galleries covered with a single soil layer are usually used to protect against rockfall. Since one-layer pr... Many rock avalanches were triggered by the Wenchuan earthquake on May 12, 2008 in southwest China. Protection galleries covered with a single soil layer are usually used to protect against rockfall. Since one-layer protection galleries do not have sufficient buffer capacity, a two-layered absorbing system has been designed. This study aims to find whether an expanded poly-styrol (EPS) cushion, which is used in the soil-covered protection galleries for shock absorption, could be positioned under dynamic loadings. The dynamic impacts of the two-layered absorbing system under the conditions of rock avalanches are numerically simulated through a 2D discrete dement method. By selecting reasonable parameters, a series of numerical experiments were conducted to find the best combination for the two- layered absorbing system. The values of the EPS layer area as a percentage of the total area were set as 0% (Sl), 22~ (S2), and 70% ($3). 22~ of the area of the EPS layer was found to be a reasonable value, and experiments were conducted to find the best position of the EPS layer in the two-layered absorbing system. The numerical results yield useful conclusions regarding the interaction between the impacting avalanches and the two-layered absorbing system. The soil layer can absorb the shock energy effectively and S2 (0.4-m thick EPS cushion covered with soil layer) is the most efficient combination, which can reduce the impact force, compared with the other combinations. 展开更多
关键词 Discrete element method Buffer capacity Dynamic simulation Impact force two-layered absorbing system
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Target-enclosing affine formation control of two-layer networked spacecraft with collision avoidance 被引量:16
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作者 Yang XU Delin LUO +2 位作者 Dongyu LI Yancheng YOU Haibin DUAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第12期2679-2693,共15页
This paper addresses a target-enclosing problem for multiple spacecraft systems by proposing a two-layer affine formation control strategy. Compared with the existing methods,the adopted two-layer network structure in... This paper addresses a target-enclosing problem for multiple spacecraft systems by proposing a two-layer affine formation control strategy. Compared with the existing methods,the adopted two-layer network structure in this paper is generally directed, which is suitable for practical space missions. Firstly, distributed finite-time sliding-mode estimators and formation controllers in both layers are designed separately to improve the flexibility of the formation control system. By introducing the properties of affine transformation into formation control protocol design,the controllers can be used to track different time-varying target formation patterns. Besides, multilayer time-varying encirclements can be achieved with particular shapes to surround the moving target. In the sequel, by integrating adaptive neural networks and specialized artificial potential functions into backstepping controllers, the problems of uncertain Euler-Lagrange models, collision avoidance as well as formation reconfiguration are solved simultaneously. The stability of the proposed controllers is verified by the Lyapunov direct method. Finally, two simulation examples of triangle formation and more complex hexagon formation are presented to illustrate the feasibility of the theoretical results. 展开更多
关键词 Affine formation control Collision avoidance Lyapunov stability Target enclosing two-layer strategy
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MOVING VELOCITIES OF PRECURSOR SOLITON GENERATION IN TWO-LAYER FLOW 被引量:4
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作者 徐肇廷 徐昱 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1998年第4期289-296,共8页
Based on the AfKdV equation of Xu et al.([1]), a theory on the velocities of the precursor soliton generation in two-layer flow over topography is presented in the present paper. Moving velocities of precursor soliton... Based on the AfKdV equation of Xu et al.([1]), a theory on the velocities of the precursor soliton generation in two-layer flow over topography is presented in the present paper. Moving velocities of precursor solitons, of the first zero-crossing of the tailing wavetrain and of the flow behind the topography are found theoretically. It is shown that for a given topography, when its moving velocities are at the resonant points, we have the following rules: the ratio of the moving velocity of the precursor solitons to that of the first zero-crossing of the tailing wavetrain equals -4/3. At the same time, the ratio of the width of generating region of the precursor solitons to that of the depressed water region equals also -4/3. The theoretical results are examined by means of numerical calculation. The comparison between the theoretical and numerical results are found in good agreement. For different stratified parameters of two-layer how, the velocities of the precursor soliton generation are also predicted in terms of the present theoretical results. 展开更多
关键词 SOLITON AfKdV equation two-layer flow generating velocity
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Penetration Depth of Torpedo Anchor in Two-Layered Cohesive Soil Bed by Free Fall 被引量:5
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作者 WANG Cheng ZHANG Min-xi YU Guo-liang 《China Ocean Engineering》 SCIE EI CSCD 2018年第6期706-717,共12页
The penetration depth of torpedo anchor in two-layered soil bed was experimentally investigated. A total of 177 experimental data were obtained in laboratory by varying the undrained shear strength of the two-layered ... The penetration depth of torpedo anchor in two-layered soil bed was experimentally investigated. A total of 177 experimental data were obtained in laboratory by varying the undrained shear strength of the two-layered soil and the thickness of the top soil layer. The geometric parameters of the anchor and the soil properties(the liquid limit, plastic limit, specific gravity, undrained shear strength, density, and water content) were measured. Based on the energy analysis and present test data, an empirical formula to predict the penetration depth of torpedo anchor in two-layered soil bed was proposed. The proposed formula was extensively validated by laboratory and field data of previous researchers. The results were in good agreement with those obtained for two-layered and single-layered soil bed.Finally, a sensitivity analysis on the parameters in the formula was performed. 展开更多
关键词 torpedo anchor penetration depth two-layered soil bed
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Asymptotic solution of a weak nonlinear model for the mid-latitude stationary wind field of a two-layer barotropic ocean 被引量:8
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作者 林万涛 张宇 莫嘉琪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期72-78,共7页
A weak nonlinear model of a two-layer barotropic ocean with Rayleigh dissipation is built.The analytic asymptotic solution is derived in the mid-latitude stationary wind field,and the physical meaning of the correspon... A weak nonlinear model of a two-layer barotropic ocean with Rayleigh dissipation is built.The analytic asymptotic solution is derived in the mid-latitude stationary wind field,and the physical meaning of the corresponding problem is discussed. 展开更多
关键词 two-layer barotropic ocean ocean model asymptotic solution
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Hydroelastic Response of A Circular Plate in Waves on A Two-Layer Fluid of Finite Depth 被引量:4
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作者 林强 卢东强 Ronald W.YEUNG 《China Ocean Engineering》 SCIE EI CSCD 2014年第5期671-686,共16页
The hydroelastic response of a circular, very large floating structure(VLFS), idealized as a floating circular elastic thin plate, is investigated for the case of time-harmonic incident waves of the surface and interf... The hydroelastic response of a circular, very large floating structure(VLFS), idealized as a floating circular elastic thin plate, is investigated for the case of time-harmonic incident waves of the surface and interfacial wave modes, of a given wave frequency, on a two-layer fluid of finite and constant depth. In linear potential-flow theory, with the aid of angular eigenfunction expansions, the diffraction potentials can be expressed by the Bessel functions. A system of simultaneous equations is derived by matching the velocity and the pressure between the open-water and the platecovered regions, while incorporating the edge conditions of the plate. Then the complex nested series are simplified by utilizing the orthogonality of the vertical eigenfunctions in the open-water region. Numerical computations are presented to investigate the effects of different physical quantities, such as the thickness of the plate, Young’s modulus, the ratios of the densities and of the layer depths, on the dispersion relations of the flexural-gravity waves for the two-layer fluid. Rapid convergence of the method is observed, but is slower at higher wave frequency. At high frequency, it is found that there is some energy transferred from the interfacial mode to the surface mode. 展开更多
关键词 wave diffraction two-layer fluid ORTHOGONALITY matched eigenfunction circular elastic plate flexural waves
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Two-layer formation-containment fault-tolerant control of fixed-wing UAV swarm for dynamic target tracking 被引量:8
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作者 QIN Boyu ZHANG Dong +1 位作者 TANG Shuo XU Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1375-1396,共22页
This paper tackles the formation-containment control problem of fixed-wing unmanned aerial vehicle(UAV)swarm with model uncertainties for dynamic target tracking in three-dimensional space in the faulty case of UAVs’... This paper tackles the formation-containment control problem of fixed-wing unmanned aerial vehicle(UAV)swarm with model uncertainties for dynamic target tracking in three-dimensional space in the faulty case of UAVs’actuator and sensor.The fixed-wing UAV swarm under consideration is organized as a“multi-leader-multi-follower”structure,in which only several leaders can obtain the dynamic target information while others only receive the neighbors’information through the communication network.To simultaneously realize the formation,containment,and dynamic target tracking,a two-layer control framework is adopted to decouple the problem into two subproblems:reference trajectory generation and trajectory tracking.In the upper layer,a distributed finite-time estimator(DFTE)is proposed to generate each UAV’s reference trajectory in accordance with the control objective.Subsequently,a distributed composite robust fault-tolerant trajectory tracking controller is developed in the lower layer,where a novel adaptive extended super-twisting(AESTW)algorithm with a finite-time extended state observer(FTESO)is involved in solving the robust trajectory tracking control problem under model uncertainties,actuator,and sensor faults.The proposed controller simultaneously guarantees rapidness and enhances the system’s robustness with fewer chattering effects.Finally,corresponding simulations are carried out to demonstrate the effectiveness and competitiveness of the proposed two-layer fault-tolerant cooperative control scheme. 展开更多
关键词 fixed-wing unmanned aerial vehicle(UAV)swarm two-layer control formation-containment dynamic target tracking
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