检索结果-南通市图书馆

china ocean engineering 2024年第2期38卷 181-182页

作者： XU wan-hai state key laboratory of Hydraulic engineering Intelligent construction and Operation Tianjin UniversityTianjin 300072China

The ocean serves as a vital carrier for human resource development and economic growth and contains rich mineral resources such as oil,natural gas,polymetallic nodules,cobalt-rich ferromanganese crusts,polymetallic sulfides,and rare earth ***,the ocean has wealthy reserves of wind,wave,tidal,and solar energy,making it an essential strategic space for sustainable future ***,offshore structures are complex.

关键词： ocean offshore tidal

delayed feedback control experiments on some flexible structures

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2010年第6期26卷 951-965页

作者： Guo-Ping cai·Long-Xiang chen department of engineering Mechanics, state key laboratory of ocean engineering, Shanghai Jiaotong University,200240 Shanghai,china department of engineering Mechanics State Key Laboratory of Ocean Engineering Shanghai Jiaotong University Shanghai China

In recent decades,studies on delayed system dynamics have attracted increasing attention and advances have been achieved in stability,nonlinearity,delay identification, delay elimination and ***,most of the existing work is on the theoretical basis and little is on the *** paper presents our experimental studies on delayed feedback control conducted in recent years with the focus on the discussion of a dSP-based delayed experiment *** phenomena in our delay experiments are discussed and a few topics of interest for further research are brought forward.

关键词： Flexible beam Flexible plate Flexible manipulator delayed feedback control Experiment

A Review on Vibration control of Multiple cylinders Subjected to FlowInduced Vibrations

在线全文

学校读者我要写书评

暂无评论

china ocean engineering 2024年第2期38卷 183-197页

作者： XU wan-hai MA Ye-xuan state key laboratory of Hydraulic engineering Intelligent construction and Operation Tianjin UniversityTianjin 300350China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The fatigue damage caused by flow-induced vibration(FIV)is one of the major concerns for multiple cylindrical structures in many engineering *** FIV suppression is of great importance for the security of many cylindrical *** active and passive control methods have been employed for the vibration suppression of an isolated cylinder undergoing vortex-induced vibrations(VIV).The FIV suppression methods are mainly extended to the multiple cylinders from the vibration control of the isolated *** to the mutual interference between the multiple cylinders,the FIV mechanism is more complex than the VIV mechanism,which makes a great challenge for the FIV *** efforts have been devoted to vibration suppression of multiple cylinder systems undergoing FIV over the past two *** control methods,such as helical strakes,splitter plates,control rods and flexible sheets,are not always effective,depending on many influence factors,such as the spacing ratio,the arrangement geometrical shape,the flow velocity and the parameters of the vibration control *** FIV response,hydrodynamic features and wake patterns of the multiple cylinders equipped with vibration control devices are reviewed and *** FIV suppression efficiency of the vibration control methods are analyzed and compared considering different influence *** research on the FIV suppression of multiple cylinders is suggested to provide insight for the development of FIV control methods and promote engineering applications of FIV control methods.

关键词： flow-induced vibration vibration control multiple cylinders tandem side-by-side staggered

Vibration control of A Flexible Marine Riser System Subject to Input dead Zone and Extraneous disturbances

在线全文

学校读者我要写书评

暂无评论

china ocean engineering 2024年第2期38卷 271-284页

作者： ZHOU Li wanG Guo-rong wan Min School of Mechatronic engineering Southwest Petroleum UniversityChengdu 610500China Energy Equipment Institute Southwest Petroleum UniversityChengdu 610500China National key laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental *** control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control ***,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each *** direction interference observers are designed to track the timevarying boundary *** this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead *** addition,the stability of the closed-loop system is proven by Lyapunov stability *** the system states are bounded,and the vibration offset of the riser converges to a small area of the initial ***,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.

关键词： adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control

Study on vibration reduction of two-scale system coupled with dynamic vibration absorber

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1335-1352页

作者： Honglin wan Xianghong LI Yongjun SHEN department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang 050043China state key laboratory of Mechanical Behavior and System Safety of Traffic engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Mechanical engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The dynamic vibration absorber with inerter and grounded stiffness(IGdVA)is used to control a two-scale system subject to a weak periodic *** vibration suppression effect is *** amplitude of the main system coupled with absorber is significantly reduced,and the high frequency vibration completely ***,through the slow-fast analysis and stability theory,it is found that the stability of the autonomous system exerts a notable regulating effect on the vibration response of the non-autonomous *** adding the dynamic vibrator absorber,the center in the autonomous system changes to an asymptotically stable focus,consequently suppressing the vibration in the non-autonomous *** research reveals that the parameters of the absorber affect the real parts of the eigenvalues of the autonomous system,thereby regulating the stability of the *** from a qualitative standpoint to a quantitative approach,a comparison of the solutions before and after the introduction of the dynamic absorber reveals that,when the grounded stiffness ratio and the mass ratio of the dynamic absorber are not equal,the high-frequency part in the analytical solution *** a result,this leads to a reduction in the amplitude of the trajectory,achieving a vibration reduction effect.

关键词： two-scale system dynamic vibration absorber vibration control inerter

Hollow Multi-shelled Structure Photoelectric Materials: Multiple Shells Bring Novel Properties

在线全文

学校读者我要写书评

暂无评论

chemical Research in chinese Universities 2024年第3期40卷 413-427页

作者： SU Fengmei wan Jiawei wanG dan state key laboratory of Biochemical engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China University of chinese Academy of Sciences Beijing 100049P.R.China key laboratory of Biopharmaceutical Preparation and delivery Chinese AcademyofSciencesBeijing 100049P.R.China

Hollow multi-shelled structures(HoMSs)have made significant strides across a wide spectrum of scientific investigations since the inception of the sequential templating approach(STA)in 2009,revealing distinctive temporal-spatial ordering *** recent establishment of a mathematical model for STA has not only demystified the formation of concentration waves within the STA process but also extended its relevance to gentler solutionbased systems,thereby broadening the HoMs ***,focusing on photoelectric applications,this review first summarizes the unique temporal-spatial ordering features of ***,the greatly enhanced properties of light capture and absorption,exciton separation,and transfer are deeply ***,we conclude with a perspective on the potential challenges and burgeoning opportunities that lie ahead in the advancement of HoMs development.

关键词： Hollow multi-shelled structure Photoelectric conversion Sequential templating approach Light absorption chargetransfer

Elucidating the structure-activity relationship of cu-Ag bimetallic catalysts for electrochemical cO_(2) reduction

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy chemistry 2024年第6期93卷 345-351,I0009页

作者： Qining Huang Lili wan Qingxuan Ren Jingshan Luo Institute of Photoelectronic Thin Film devices and Technology State Key Laboratory of Photovoltaic Materials and CellsKey Laboratory of Photoelectronic Thin Film Devices and Technology of TianjinMinistry of Education Engineering Research Center of Thin Film Photoelectronic TechnologyNankai UniversityTianjin 300350China Frontiers Science center for New Organic Matter Nankai UniversityTianjin 300071China Haihe laboratory of Sustainable chemical Transformations Tianjin 300192China

developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical cO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst ***,we prepared two cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of cu *** tested in a flow cell,the cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the *** catalysts were further studied in the H-cell and zero-gap MEA *** was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic *** work elucidates the structure-activity relationship of bimetallic catalysts for cO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity.

关键词： Electrochemical cO_(2)reduction Bimetallic catalyst cu-Ag Structure-activity relationship

WAVE-cURRENT INTERAcTIONS WITH THREE-dIMENSIONAL FLOATING BOdIES

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2010年第2期22卷 229-240页

作者： LIU Zhen TENG Bin NING de-zhi GOU Ying state key laboratory of coastal and Offshore engineering Dalian University of Technology Dalian 116024China state key laboratory of Satellite ocean Environment dyamics Hangzhou 310012 China

A Time-domain Higher-Order Boundary Element Method（THOBEM） is developed for simulating wave-current interactions with 3-d floating *** a Taylor series expansion and a perturbation procedure,the model is formulated to the first-order in the wave steepness and in the current velocity,*** boundary value problem is decomposed into a steady double-body flow problem and an unsteady wave ***-order boundary integral equation methods are then used to solve the proposed problems with a fourth-order Runge-Kutta method for the time *** artificial damping layer is adopted to dissipate the scattering *** from the other time-domain numerical models,which are often focused on the wave-current interaction with restrained bodies,the present model deals with a floating *** numerical results of wave forces,wave run-up and body response are all in a close agreement with those obtained by frequency-domain *** proposed numerical model is further applied to investigate wave-current interactions with a floating body of complicated *** this work,the regular and focused wave combined with current interacting with a truss-spar platform is investigated.

关键词： wave-current interaction floating bodies time-domain simulation Time-domain Higher-Order Boundary Element Method(THOBEM)

Enhancing comprehension of water vapor on adsorption performance of VOc on porous carbon materials and its application challenge

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & engineering 2024年第9期18卷 51-66页

作者： Xiaolong Yao Kuan wan Wenxin Yu Zheng Liu School of Ecology and Environment Beijing Technology and Business UniversityBeijing 100048China state Environmental Protection key laboratory of Food chain Pollution control Beijing Technology and Business UniversityBeijing 100048China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China

Volatile organic compounds(VOc)have been proven to cause considerable harm to both the ecological environment and human *** VOc emissions are primarily generated by the industrial *** utilization of porous carbon as an adsorbent has emerged as an effective method for the efficient removal of VOc from industrial ***,during the actual production processes,VOc exhaust gases are often mixed with water vapor,which poses challenges for adsorption *** review provides a comprehensive overview of the remarkable advancements in various carbon materials in terms of their ability to adsorb both VOc and water ***,it systematically summarizes the influence of surface groups on adsorbents and the molecular properties of VOc on their adsorption by carbon ***,this review introduces the mechanism underlying adsorption-adsorbent interactions and discusses the construction of models for adsorbing water vapor and *** challenges associated with the application of carbon materials for VOc adsorption in humid environments are also *** review aims to offer theoretical and technical guidance for the effective purification of moist VOc waste gases emitted from industrial sources,thereby achieving precise control of VOc emissions.

关键词： Adsorption Water vapor carbon-based adsorbents Surface functional groups VOc properties