资源类型

期刊论文 165

会议视频 4

年份

2023 14

2022 6

2021 18

2020 11

2019 8

2018 6

2017 11

2016 4

2015 9

2014 5

2013 7

2012 13

2011 13

2010 7

2009 10

2008 4

2007 7

2006 4

2005 3

2003 2

展开 ︾

关键词

N-糖组 1

N-糖基化 1

COVID-19 1

Dirac理论 1

GC-Q-TOFMS 1

GH位移 1

GaAs基微结构材料 1

IgG抗体 1

LC-Q-TOFMS 1

Maxwell方程组 1

N-聚糖 1

PHEMT 1

Proca方程组 1

hACE2 1

中国队列 1

中药 1

亲水相互作用液相色谱法 1

人工智能 1

他汀类药物 1

展开 ︾

检索范围:

排序: 展示方式:

Parametric control of structural responses using an optimal passive tuned mass damper under stationary

Min-Ho CHEY, Jae-Ung KIM

《结构与土木工程前沿(英文)》 2012年 第6卷 第3期   页码 267-280 doi: 10.1007/s11709-012-0170-x

摘要: In this study, the structural control strategy utilizing a passive tuned mass damper (TMD) system as a seismic damping device is outlined, highlighting the parametric optimization approach for displacement and acceleration control. The theory of stationary random processes and complex frequency response functions are explained and adopted. For the vibration control of an undamped structure, the optimal parameters of a TMD, such as the optimal tuning frequency and optimal damping ratio, to stationary Gaussian white noise acceleration are investigated by using a parametric optimization procedure. For damped structures, a numerical searching technique is used to obtain the optimal parameters of the TMD, and then the explicit formulae for these optimal parameters are derived through a sequence of curve-fitting schemes. Using these specified optimal parameters, several different controlled responses are examined, and then the displacement and acceleration based control effectiveness indices of the TMD are examined from the view point of RMS values. From the viewpoint of the RMS values of displacement and acceleration, the optimal TMDs adopted in this study shows clear performance improvements for the simplified model examined, and this means that the effective optimization of the TMD has a good potential as a customized target response-based structural strategy.

关键词: tuned mass damper     parametric optimization     passive control     white noise     earthquake excitation    

A combined control strategy using tuned liquid dampers to reduce displacement demands of base-isolated

Parham SHOAEI, Houtan Tahmasebi OROMI

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 890-903 doi: 10.1007/s11709-019-0524-8

摘要: This paper investigates a hybrid structural control system using tuned liquid dampers (TLDs) and lead-rubber bearing (LRB) systems for mitigating earthquake-induced vibrations. Furthermore, a new approach for taking into account the uncertainties associated with the steel shear buildings is proposed. In the proposed approach, the probabilistic distributions of the stiffness and yield properties of stories of a set of reference steel moment frame structures are derived through Monte-Carlo sampling. The approach is applied to steel shear buildings isolated with LRB systems. The base isolation systems are designed for different target base displacements by minimizing a relative performance index using Genetic Algorithm. Thereafter, the base-isolated structures are equipped with TLDs and a combination of the base and TLD properties is sought by which the maximum reduction occurs in the base displacement without compromising the performance of the system. In addition, the effects of TLD properties on the performance of the system are studied through a parametric study. Based on the analyses results, the base displacement can be reduced 23% by average, however, the maximum reduction can go beyond 30%.

关键词: tuned liquid damper     lead-rubber bearing system     probabilistic framework     steel shear building     relative performance index     Monte-Carlo sampling    

Innovative seismic retrofitting strategy of added stories isolation system

Min-Ho CHEY, J. Geoffrey CHASE, John B. MANDER, Athol J. CARR

《结构与土木工程前沿(英文)》 2013年 第7卷 第1期   页码 13-23 doi: 10.1007/s11709-013-0195-9

摘要: The seismic performance of “added stories isolation” (ASI) systems are investigated for 12-story moment resisting frames. The newly added and isolated upper stories on the top of the existing structure are rolled to act as a large tuned mass damper (TMD) to overcome the limitation of the size of tuned mass, resulting to “12+2” and “12+4” stories building configurations. The isolation layer, as a core design strategy, is optimally designed based on optimal TMD design principle, entailing the insertion of passive flexible laminated rubber bearings to segregate two or four upper stories from a conventionally constructed lower superstructure system. Statistical performance metrics are presented for 30 earthquake records from the 3 suites of the SAC project. Time history analyses are used to compute various response performances and reduction factors across a wide range of seismic hazard intensities. Results show that ASI systems can effectively manage seismic response for multi-degree-of freedom (MDOF) systems across a broader range of ground motions without requiring burdensome extra mass. Specific results include the identification of differences in the number of added story by which the suggested isolation systems remove energy.

关键词: added stories     seismic isolation     tuned mass damper     parametric optimization     statistical method    

Aseismic smart building isolation systems under multi-level earthquake excitations: Part I, conceptual design and nonlinear analysis

Min-Ho CHEY,J. Geoffrey CHASE,John B. MANDER,Athol J. CARR

《结构与土木工程前沿(英文)》 2015年 第9卷 第3期   页码 286-296 doi: 10.1007/s11709-015-0307-9

摘要: As a novel structural control strategy, tuned mass damper (TMD) inspired passive and semi-active smart building isolation systems are suggested to reduce structural response and thus mitigate structural damage due to earthquake excitations. The isolated structure’s upper stories can be utilized as a large scaled TMD, and the isolation layer, as a core design point, between the separated upper and lower stories entails the insertion of rubber bearings and (i) viscous dampers (passive) or (ii) resettable devices (semi-active). The seismic performance of the suggested isolation systems are investigated for 12-story reinforced concrete moment resisting frames modeled as “10+ 2” stories and “8+ 4” stories. Passive viscous damper or semi-active resettable devices are parametrically evaluated through the optimal design principle of a large mass ratio TMD. Statistical performance metrics are presented for 30 earthquake records from the three suites of the SAC project. Based on nonlinear structural models, including P-delta effects and modified Takeda hysteresis, the inelastic time history analyses are conducted to compute the seismic performances across a wide range of seismic hazard intensities. Results show that semi-active smart building isolation systems can effectively manage seismic response for multi-degree-of freedom (MDOF) systems across a broader range of ground motions in comparison to uncontrolled case and passive solution.

关键词: tuned mass damper     smart building isolation     resettable device     non-linear     statistical assessment    

A hybrid LQR-PID control design for seismic control of buildings equipped with ATMD

Amir Hossein HEIDARI, Sadegh ETEDALI, Mohamad Reza JAVAHERI-TAFTI

《结构与土木工程前沿(英文)》 2018年 第12卷 第1期   页码 44-57 doi: 10.1007/s11709-016-0382-6

摘要: This paper presents an efficient hybrid control approach through combining the idea of proportional-integral-derivative (PID) controller and linear quadratic regulator (LQR) control algorithm. The proposed LQR-PID controller, while having the advantage of the classical PID controller, is easy to implement in seismic-excited structures. Using an optimization procedure based on a cuckoo search (CS) algorithm, the LQR-PID controller is designed for a seismic- excited structure equipped with an active tuned mass damper (ATMD). Considering four earthquakes, the performance of the proposed LQR-PID controller is evaluated. Then, the results are compared with those given by a LQR controller. The simulation results indicate that the LQR-PID performs better than the LQR controller in reduction of seismic responses of the structure in the terms of displacement and acceleration of stories of the structure.

关键词: seismic control     tuned mass dampers     cuckoo search     PID controller     LQR controller    

Economic analysis of a hybrid solar-fuel cell power delivery system using tuned genetic algorithm

Trina SOM, Niladri CHAKRABORTY

《能源前沿(英文)》 2012年 第6卷 第1期   页码 12-20 doi: 10.1007/s11708-012-0172-3

摘要: An economic evaluation of a network of distributed energy resources (DERs) comprising a microgrid structure of power delivery system in an Indian scenario has been made. The mathematical analysis is based on the application of tuned genetic algorithm (TGA). The analyses for optimal power operation pertaining to minimum cost have been made for two cases in Indian power delivery system. The first case deals with the consumers’ individual optimal operation of DERs, while in the second one, consumers altogether form a microgrid with the optimal supply of power from DERs. The total annual costs for these two cases are found to be economically competitive and encouraging. A reduction of approximately 5.7% in the annual cost has been obtained in the case of microgid system than that in the separately operating consumers’ system for a small locality of India. It is observed that the application of TGA results in a reduction of the minimum cost depicting an improved outcome in terms of energy economy.

关键词: distributed energy resources (DERs)     microgrid     tuned genetic algorithm (TGA)    

Evaluation of a developed bypass viscous damper performance

Mahrad FAHIMINIA, Aydin SHISHEGARAN

《结构与土木工程前沿(英文)》 2020年 第14卷 第3期   页码 773-791 doi: 10.1007/s11709-020-0627-2

摘要: In this study, the dynamic behavior of a developed bypass viscous damper is evaluated. Bypass viscous damper has a flexible hose as an external orifice through which the inside fluid transfer from one side to the other side of the inner piston. Accordingly, the viscosity coefficient of the damper can be adjusted using geometrical dimensions of the hose. Moreover, the external orifice acts as a thermal compensator and alleviates viscous heating of the damper. According to experimental results, Computational Fluid Dynamic (CFD) model, a numerical formula and the simplified Maxwell model are found and assessed; therefore, the verification of numerical and computational models are evaluated for simulating. Also, a simplified procedure is proposed to design structures with bypass viscous dampers. The design procedure is applied to design an 8-story hospital structure with bypass viscous dampers, and it is compared with the same structure, which is designed with concentric braces and without dampers. Nonlinear time history analyses revealed that the hospital with viscous damper experiences less structural inelastic demands and fewer story accelerations which mean fewer demands on nonstructural elements. Moreover, seismic behaviors of nonstructural masonry claddings are also compared in the cases of hospital structure with and without dampers.

关键词: developed viscous damper     external orifice     energy dissipation     seismic behavior     CFD model of viscous damper     a simplified model    

Dynamic modeling of hydrostatic guideway considering compressibility and inertia effect

Yikang DU,Kuanmin MAO,Yaming ZHU,Fengyun WANG,Xiaobo MAO,Bin LI

《机械工程前沿(英文)》 2015年 第10卷 第1期   页码 78-88 doi: 10.1007/s11465-015-0331-4

摘要:

Hydrostatic guideways are used as an alternative to contact bearings due to high stiffness and high damping in heavy machine tools. To improve the dynamic characteristic of bearing structure, the dynamic modeling of the hydrostatic guidway should be accurately known. This paper presents a “mass-spring-Maxwell” model considering the effects of inertia, squeeze, compressibility and static bearing. To determine the dynamic model coefficients, numerical simulation of different cases between displacement and dynamic force of oil film are performed with fluent code. Simulation results show that hydrostatic guidway can be taken as a linear system when it is subjected to a small oscillation amplitude. Based on a dynamic model and numerical simulation, every dynamic model’s parameters are calculated by the Levenberg-Marquardt algorithm. Identification results show that “mass-spring-damper” model is the most appropriate dynamic model of the hydrostatic guidway. This paper provides a reference and preparation for the analysis of the dynamic model of the similar hydrostatic bearings.

关键词: hydrostatic guidway     dynamic model     dynamic mesh technique     Levenberg-Marquardt     mass-spring-damper model    

Reactive power compensation of an isolated hybrid power system with load interaction using ANFIS tuned

Nitin SAXENA,Ashwani KUMAR

《能源前沿(英文)》 2014年 第8卷 第2期   页码 261-268 doi: 10.1007/s11708-014-0298-6

摘要: This paper presents an adaptive neuro fuzzy interference system (ANFIS) based approach to tune the parameters of the static synchronous compensator (STATCOM) with frequent disturbances in load model and power input of a wind-diesel based isolated hybrid power system (IHPS). In literature, proportional integral (PI) based controller constants are optimized for voltage stability in hybrid systems due to the interaction of load disturbances and input power disturbances. These conventional controlling techniques use the integral square error (ISE) criterion with an open loop load model. An ANFIS tuned constants of a STATCOM controller for controlling the reactive power requirement to stabilize the voltage variation is proposed in the paper. Moreover, the interaction between the load and the isolated power system is developed in terms of closed loop load interaction with the system. Furthermore, a comparison of transient responses of IHPS is also presented when the system has only the STATCOM and the static compensation requirement of the induction generator is fulfilled by the fixed capacitor, dynamic compensation requirement, meanwhile, is fulfilled by STATCOM. The model is tested for a 1% step increase in reactive power load demand at = 0 s and then a sudden change of 3% from the 1% at = 0.01 s for a 1% step increase in power input at variable wind speed model.

关键词: isolated wind-diesel power system     adaptive neuro fuzzy interference system (ANFIS)     integral square error (ISE) criterion     load interaction    

Hysteretic behavior of cambered surface steel tube damper: Theoretical and experimental research

《结构与土木工程前沿(英文)》 2023年 第17卷 第4期   页码 606-624 doi: 10.1007/s11709-023-0925-6

摘要: A novel cambered surface steel tube damper (CSTD) with a cambered surface steel tube and two concave connecting plates is proposed herein. The steel tube is the main energy dissipation component and comprises a weakened segment in the middle, a transition segment, and an embedded segment. It is believed that during an earthquake, the middle weakened segment of the CSTD will be damaged, whereas the reliability of the end connection is ensured. Theoretical and experimental studies are conducted to verify the effectiveness of the proposed CSTD. Formulas for the initial stiffness and yield force of the CSTD are proposed. Subsequently, two CSTD specimens with different steel tube thicknesses are fabricated and tested under cyclic quasi-static loads. The result shows that the CSTD yields a stable hysteretic response and affords excellent energy dissipation. A parametric study is conducted to investigate the effects of the steel tube height, diameter, and thickness on the seismic performance of the CSTD. Compared with equal-stiffness design steel tube dampers, the CSTD exhibits better energy dissipation performance, more stable hysteretic response, and better uniformity in plastic deformation distributions.

关键词: cambered surface steel tube damper     energy dissipation capacity     finite element model     hysteretic performance     parametric study    

Computation and investigation of mode characteristics in nonlinear system with tuned/mistuned contact

Houxin SHE, Chaofeng LI, Qiansheng TANG, Hui MA, Bangchun WEN

《机械工程前沿(英文)》 2020年 第15卷 第1期   页码 133-150 doi: 10.1007/s11465-019-0557-7

摘要: This study derived a novel computation algorithm for a mechanical system with multiple friction contact interfaces that is well-suited to the investigation of nonlinear mode characteristic of a coupling system. The procedure uses the incremental harmonic balance method to obtain the nonlinear parameters of the contact interface. Thereafter, the computed nonlinear parameters are applied to rebuild the matrices of the coupling system, which can be easily solved to calculate the nonlinear mode characteristics by standard iterative solvers. Lastly, the derived method is applied to a cycle symmetry system, which represents a shaft–disk–blade system subjected to dry friction. Moreover, this study analyzed the effects of the tuned and mistuned contact features on the nonlinear mode characteristics. Numerical results prove that the proposed method is particularly suitable for the study of nonlinear characteristics in such nonlinear systems.

关键词: coupling vibration     nonlinear mode     original algorithm     contact interface    

Constriction factor based particle swarm optimization for analyzing tuned reactive power dispatch

Syamasree BISWAS(RAHA), Kamal Krishna MANDAL, Niladri CHAKRABORTY

《能源前沿(英文)》 2013年 第7卷 第2期   页码 174-181 doi: 10.1007/s11708-013-0246-x

摘要: The reactive power dispatch (RPD) problem is a very critical optimization problem of power system which minimizes the real power loss of the transmission system. While solving the said problem, generator bus voltages and transformer tap settings are kept within a stable operating limit. In connection with the RPD problem, solving reactive power is compensated by incorporating shunt capacitors. The particle swarm optimization (PSO) technique is a swarm intelligence based fast working optimization method which is chosen in this paper as an optimization tool. Additionally, the constriction factor is included with the conventional PSO technique to accelerate the convergence property of the applied optimization tool. In this paper, the RPD problem is solved in the case of the two higher bus systems, i.e., the IEEE 57-bus system and the IEEE 118-bus system. Furthermore, the result of the present paper is compared with a few optimization technique based results to substantiate the effectiveness of the proposed study.

关键词: real power loss minimization     voltage stability     constriction factor     particle swarm optimization (PSO)    

Effect of magneto rheological damper on tool vibration during hard turning

P. Sam PAUL, A. S. VARADARAJAN

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 410-416 doi: 10.1007/s11465-012-0341-4

摘要:

Recently, the concept of hard turning has gained considerable attention in metal cutting as it can apparently replace the traditional process cycle of turning, heat treating, and finish grinding for assembly of hard wear resistant steel parts. The present investigation aims at developing a magneto rheological (MR) fluid damper for suppressing tool vibration and promoting better cutting performance during hard turning. The magneto rheological Fluid acts as a viscoelastic spring with non-linear vibration characteristics that are controlled by the composition of the magneto rheological fluid, the shape of the plunger and the electric parameters of the magnetizing field. Cutting experiments were conducted to arrive at a set of electrical, compositional and shape parameters that can suppress tool vibration and promote better cutting performance during turning of AISI 4340 steel of 46 HRC with minimal fluid application using hard metal insert with sculptured rake face. It was observed that the use of MR fluid damper reduces tool vibration and improves the cutting performance effectively. Also commercialization of this idea holds promise to the metal cutting industry.

关键词: tool vibration     magneto rheological damper     hard turning     surface finish     tool wear    

Analytical study on damping performances of magnetorheological grease damper based on disk squeeze mode

Danxia ZHAO, Changrong LIAO, Qiong LIU, Jing LUO

《机械工程前沿(英文)》 2011年 第6卷 第3期   页码 312-317 doi: 10.1007/s11465-011-0235-x

摘要:

In this paper, a small displacement-type magnetorheological grease (MRG) damper based on disk squeeze mode is proposed. The squeeze flow differential equation is obtained. The Navier slip condition is considered on the surfaces and the boundary compatible condition is established. The radial velocity profiles and the radial pressure distributions are derived respectively, and the mathematical stress expression is calculated. To verify rationality of analytical method, the MRG damper is designed and fabricated according to the technical requirements of an engine vibration isolation system. The experimental damping force from MTS870 Electro-hydraulic Servo with sine wave excitation shows that the proposed analytical method is feasible and provides the reference value for designing MRG damper based on disk squeeze mode.

关键词: magnetorheological grease (MRG)     damper     squeeze model    

Application of coupled multi-body dynamics–discrete element method for optimization of particle damper

Danhui DAN, Qianqing WANG, Jiongxin GONG

《结构与土木工程前沿(英文)》 2021年 第15卷 第1期   页码 244-252 doi: 10.1007/s11709-021-0696-x

摘要: With the application of the particle damping technology to cable vibration attenuation, the rootless cable damper overcomes the limit in installation height of existing dampers. Damping is achieved through energy dissipation by collisions and friction. In this paper, a coupled multi-body dynamics–discrete element method is proposed to simulate the damping of the damper–cable system under a harmonic excitation. The analyses are done by combining the discrete element method in EDEM and multi-body dynamics in ADAMS. The simulation results demonstrate the damping efficiency of rootless particle damper under different excitations and reveal the influence of the design parameters on its performance, including the filling ratio, particle size, coefficient of restitution, and coefficient of friction.

关键词: granular material     vibration control     discrete element method     particle damper     cable vibration    

标题 作者 时间 类型 操作

Parametric control of structural responses using an optimal passive tuned mass damper under stationary

Min-Ho CHEY, Jae-Ung KIM

期刊论文

A combined control strategy using tuned liquid dampers to reduce displacement demands of base-isolated

Parham SHOAEI, Houtan Tahmasebi OROMI

期刊论文

Innovative seismic retrofitting strategy of added stories isolation system

Min-Ho CHEY, J. Geoffrey CHASE, John B. MANDER, Athol J. CARR

期刊论文

Aseismic smart building isolation systems under multi-level earthquake excitations: Part I, conceptual design and nonlinear analysis

Min-Ho CHEY,J. Geoffrey CHASE,John B. MANDER,Athol J. CARR

期刊论文

A hybrid LQR-PID control design for seismic control of buildings equipped with ATMD

Amir Hossein HEIDARI, Sadegh ETEDALI, Mohamad Reza JAVAHERI-TAFTI

期刊论文

Economic analysis of a hybrid solar-fuel cell power delivery system using tuned genetic algorithm

Trina SOM, Niladri CHAKRABORTY

期刊论文

Evaluation of a developed bypass viscous damper performance

Mahrad FAHIMINIA, Aydin SHISHEGARAN

期刊论文

Dynamic modeling of hydrostatic guideway considering compressibility and inertia effect

Yikang DU,Kuanmin MAO,Yaming ZHU,Fengyun WANG,Xiaobo MAO,Bin LI

期刊论文

Reactive power compensation of an isolated hybrid power system with load interaction using ANFIS tuned

Nitin SAXENA,Ashwani KUMAR

期刊论文

Hysteretic behavior of cambered surface steel tube damper: Theoretical and experimental research

期刊论文

Computation and investigation of mode characteristics in nonlinear system with tuned/mistuned contact

Houxin SHE, Chaofeng LI, Qiansheng TANG, Hui MA, Bangchun WEN

期刊论文

Constriction factor based particle swarm optimization for analyzing tuned reactive power dispatch

Syamasree BISWAS(RAHA), Kamal Krishna MANDAL, Niladri CHAKRABORTY

期刊论文

Effect of magneto rheological damper on tool vibration during hard turning

P. Sam PAUL, A. S. VARADARAJAN

期刊论文

Analytical study on damping performances of magnetorheological grease damper based on disk squeeze mode

Danxia ZHAO, Changrong LIAO, Qiong LIU, Jing LUO

期刊论文

Application of coupled multi-body dynamics–discrete element method for optimization of particle damper

Danhui DAN, Qianqing WANG, Jiongxin GONG

期刊论文