Articoli di riviste: "Dynamic equivalent method"

1

Gonidou, Luc-Olivier, Jean-Louis Nicks e François Dekmeer. "Equivalent F* Method for Dynamic Reanalysis". AIAA Journal 58, n. 4 (aprile 2020): 1891–96. http://dx.doi.org/10.2514/1.j058737.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

2

FRITTELLI, MARCO, e MARCO MAGGIS. "CONDITIONAL CERTAINTY EQUIVALENT". International Journal of Theoretical and Applied Finance 14, n. 01 (febbraio 2011): 41–59. http://dx.doi.org/10.1142/s0219024911006255.

Testo completo

Abstract (sommario):

In a dynamic framework, we study the conditional version of the classical notion of certainty equivalent when the preferences are described by a stochastic dynamic utility u(x,t,ω). We introduce an appropriate mathematical setting, namely Orlicz spaces determined by the underlying preferences and thus provide a systematic method to go beyond the case of bounded random variables. Finally we prove a conditional version of the dual representation which is a crucial prerequisite for discussing the dynamics of certainty equivalents.

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Zhang, Wei, Chuan Qiong Sun e Huan Wang. "Equivalent Static Loads Method for Flexible Structural Shape Optimization". Advanced Materials Research 308-310 (agosto 2011): 2364–67. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.2364.

Testo completo

Abstract (sommario):

Study on the flexible structural shape optimization problem under dynamic loading conditions. The dynamic loads are transformed to equivalent static loads (ESLs), and then the static response optimization can be used for dynamic response optimization. A structural shape optimization model, which has been established by ESls method, is utilized to design the flexible components in the multibody dynamic system. A shape optimization for a four-bar linkage had been generated by using the ESLs method, and the results indicate that there are noticeable improvements in the total mass and the maximum stress.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Martin, K., C. Escudero, A. Erkoreka, I. Flores e J. M. Sala. "Equivalent wall method for dynamic characterisation of thermal bridges". Energy and Buildings 55 (dicembre 2012): 704–14. http://dx.doi.org/10.1016/j.enbuild.2012.08.024.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Zheng, Wenzhe, Jing Bu, Ningyu Zhang, Qian Zhou e Jiankun Liu. "Dynamic Equivalence of Wind Farms Considering Complex Terrain". MATEC Web of Conferences 260 (2019): 02013. http://dx.doi.org/10.1051/matecconf/201926002013.

Testo completo

Abstract (sommario):

The dynamic equivalence of wind farms is widely used for model simplification. While, the accuracy will be lower without considering the influence of wind speed correlation caused by topography and wake effect. In order to improve the accuracy, this paper proposes a dynamic cluster equivalence method of coherent generators based on hierarchical clustering analysis. Firstly, it analyses the impacts of equivalence’s accuracy such as wind speed distribution, wake effect and control strategy of turbine. Then, it uses hierarchical clustering method to correlate the disturbed trajectory of rotor current of the intra-site turbines and obtains the dynamic clustering results. Finally, it uses power loss method to obtain the equivalent parameters of multi-machine equivalent model. Simulation results verify the effectiveness of this method.

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Cai, Yongyang, Kenneth Judd e Jevgenijs Steinbuks. "A nonlinear certainty equivalent approximation method for dynamic stochastic problems". Quantitative Economics 8, n. 1 (marzo 2017): 117–47. http://dx.doi.org/10.3982/qe533.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Broccardo, Marco, e Armen Der Kiureghian. "Nonlinear stochastic dynamic analysis by evolutionary tail-equivalent linearization method". Structural Safety 90 (maggio 2021): 102044. http://dx.doi.org/10.1016/j.strusafe.2020.102044.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Guo, Ning, Hao Chen, Zhong Zhang, Fei Du e Chao Xu. "Comparative study of dynamically equivalent modeling methods for honeycomb sandwich structure: numerical simulations and experiments". Mechanical Sciences 11, n. 2 (11 settembre 2020): 317–28. http://dx.doi.org/10.5194/ms-11-317-2020.

Testo completo

Abstract (sommario):

Abstract. The structure of the lightweight honeycomb sandwich panel is complex. Thus, establishing an equivalent simplified model is indispensable to improve the efficiency of the dynamic analysis of honeycomb sandwich panels. In this paper, three commonly used dynamically equivalent modeling methods for honeycomb sandwich panel are studied: a dynamically equivalent method based on laminated plate theory, a single-layer plate equivalent method based on the theory of Hoff (1948), and an improved equivalent method based on Allen (1969). Using theoretical study, numerical simulations, and experiments, the applicability of these equivalent methods and the effect of design parameters on the dynamic characteristics are studied, and the optimal dynamically equivalent method for honeycomb sandwich panels is obtained.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Wang, Ran, Hao Tian, Hong Liu Wang, Yang Zhao, Chen Yang e Xin Bin Hou. "SSPS Dynamic Modeling and the Flexible Vibration Suppression". Applied Mechanics and Materials 799-800 (ottobre 2015): 724–27. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.724.

Testo completo

Abstract (sommario):

Space solar power satellite (SSPS) as a very large flexible spacecraft structure with complex configuration, large size and number of units bring the difficulties to dynamics modeling and analysis. Considering SSPS structure characteristics, equivalent strain and kinetic energy theory is adopted to establish the equivalent beam model of SSPS truss structure. The assumed mode method is adopted to describe the flexible body. The modal truncation method implements the dynamics system order reduction. Mixed coordinates method is adopted to establish the rigid-flexible coupled dynamic model. The established dynamic model can reflect dynamic characteristics of SSPS, achieve control requirements for SSPS and decrease the workload of simulation calculation. The independent modal space control (IMSC) method is proposed to active control research view of the large displacement, nonlinearity, low and dense mode frequency, light damping of flexible structures. Simulation results on flexible solar array show the effectiveness of the control method.

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Wei, Changzhu, Ruiming Wang, Wei Zheng e Jialun Pu. "Equivalent dynamic modeling of flexible morphing aircraft". Science Progress 104, n. 2 (aprile 2021): 003685042110109. http://dx.doi.org/10.1177/00368504211010946.

Testo completo

Abstract (sommario):

A morphing aircraft can maintain optimal flight performance by adaptively changing shape. However, large deformation and fast motion of aircraft modules lead to complicated dynamics during morphing process. This paper proposes a mechanistic equivalent model with parameters identified by optimization method. Based on the dynamics of the aircraft modules with large deformation and fast motion and considering the coupling characteristics of rigid bodies and gimbal joints, an equivalent dynamic model of morphing aircraft is built in this study. Considering the huge amount of highly coupled parameters in the equivalent model, particle swarm optimization algorithm is used to identify the equivalent parameters based on the sample data of flexible model. By comparing the simulation results of proposed model to those of rigid model and flexible model, it can be seen that the accuracy of the proposed equivalent model is comparable to that of the flexible model, but the computational load is only 10% of that of flexible model. Further, based on this high-fidelity model with low computational load, an optimized morphing process is obtained, and the attitude variation during morphing is reduced by 4.23%.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Guo, Hongwei, Chuang Shi, Meng Li, Zongquan Deng e Rongqiang Liu. "Design and Dynamic Equivalent Modeling of Double-Layer Hoop Deployable Antenna". International Journal of Aerospace Engineering 2018 (2018): 1–15. http://dx.doi.org/10.1155/2018/2941981.

Testo completo

Abstract (sommario):

This study proposes deployable units driven by elastic hinges and a double-layer hoop deployable antenna composed of these units. A rational modeling method based on the energy equivalence principle is presented to develop an equivalent model of the double-layer hoop antenna in accordance with the structural characteristics of the antenna. The equivalent beam models of the rods with elastic hinges are proposed. The relationship of geometrical and material parameters is established considering the strain energy and the kinetic energy of the periodic unit, which are the same as those of the equivalent beam in the same displacement field. The equivalent model of the antenna is obtained by assembling several equivalent beam models in the circumferential direction. The precision of the equivalent model of the antenna is acceptable as found by comparing the modal analysis results obtained through equivalent model calculation, finite element simulation, and modal test.

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Agrawal, Rimjhim, e Thukaram Dhadbanjan. "Zonal Dynamic Equivalents Based on the Concept of Relative Electrical Distance". International Journal of Emerging Electric Power Systems 14, n. 2 (30 maggio 2013): 175–88. http://dx.doi.org/10.1515/ijeeps-2012-0050.

Testo completo

Abstract (sommario):

Abstract: This article presents a systematic approach to construct the zonal dynamic equivalents of a large-power system based on the concept of relative electrical distance (RED). The task of dynamic equivalencing is to eliminate the full model of the external system and replace it with an equivalent model, which has dynamic characteristics close enough to the full model. The dynamic equivalent models are used for large-scale power system offline transient stability analysis with large disturbance. Dynamic equivalencing also helps in reducing the computation burden and memory requirements in wide area monitoring system (WAMS) for online stability assessment. The procedure is illustrated on IEEE 39 bus system and on a practical 205 bus system consisting of three zones of Indian Southern grid, where an equivalent of a zone has been constructed. The simulation results of the original system and equivalent system are compared. The proposed approach is also compared with the existing Ward equivalent method and the results are found to be similar. The simulation results show that the developed equivalent system has close accuracy in representing the dynamic characteristics of the original system.

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Limon-Miro, Ana Teresa, Veronica Lopez-Teros e Humberto Astiazaran-Garcia. "Dynamic Macronutrient Meal-Equivalent Menu Method: Towards Individual Nutrition Intervention Programs". Methods and Protocols 2, n. 3 (5 settembre 2019): 78. http://dx.doi.org/10.3390/mps2030078.

Testo completo

Abstract (sommario):

Nutrition interventions should reflect the state of the art in science and dietetics to meet each patient’s requirements. Incorporating new knowledge into individualized food-based nutrition interventions is a major challenge, and health care professionals constantly search for novel approaches through specific and standardized methods. The dynamic macronutrient meal-equivalent menu method involves individuals making informed food choices that match their requirements, schedule, and food availability and affinity, helping them maintain a sense of control and motivation to adhere to a nutrition intervention program. This protocol includes the steps required to prepare a nutrition plan containing equivalent meal options consistent with the patient’s needs and preferences. Standard food servings are planned according to population specific dietary guidelines and individual characteristics. Servings are distributed at required mealtimes, and are all equivalent in energy and macronutrient content, providing every patient with interchangeable choices within each mealtime. This empowers individuals to select foods in a guided format whilst adhering to a dietary plan. Acceptable variations for calculated energy and macronutrient content are as follows: protein ±1 g/day, fat ±1 g/day, carbohydrate ±2 g/day, and energy ±15 kcal/day. Following this method, health care professionals can develop individualized nutrition intervention programs that may improve patients’ adherence, nutritional status, and health.

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Shuai, Zhikang, Yelun Peng, Xuan Liu, Zuyi Li, Josep M. Guerrero e Z. John Shen. "Dynamic Equivalent Modeling for Multi-Microgrid Based on Structure Preservation Method". IEEE Transactions on Smart Grid 10, n. 4 (luglio 2019): 3929–42. http://dx.doi.org/10.1109/tsg.2018.2844107.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Zheng, Zhibao, e Hongzhe Dai. "A new fractional equivalent linearization method for nonlinear stochastic dynamic analysis". Nonlinear Dynamics 91, n. 2 (13 novembre 2017): 1075–84. http://dx.doi.org/10.1007/s11071-017-3929-8.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Lee, Hyun-Ah, e Gyung-Jin Park. "Nonlinear dynamic response topology optimization using the equivalent static loads method". Computer Methods in Applied Mechanics and Engineering 283 (gennaio 2015): 956–70. http://dx.doi.org/10.1016/j.cma.2014.10.015.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Wang, Zhiwei, Yi Liu e Feng Wang. "Rapid calculation method for estimating static and dynamic performances of closed hydrostatic guideways". Industrial Lubrication and Tribology 69, n. 6 (13 novembre 2017): 1040–48. http://dx.doi.org/10.1108/ilt-01-2017-0003.

Testo completo

Abstract (sommario):

Purpose The purpose of this paper is to establish a simplified model of the closed hydrostatic guideway for the rapid analysis of static and dynamic characteristics. Further, the influence of compressibility and dynamic frequency are taken into consideration in the new dynamic model. Design/methodology/approach The new model is based on the second kind of Lagrange equation. In this model, the closed hydrostatic guideway is supported by 12 pads, and each oil pad is equivalent to a nonlinear spring-damper system. The equivalent spring coefficient and damper coefficient of the oil pad are extracted by the three different equivalent methods. Finally, the validation experiments of step load response and dynamic stiffness are conducted on a hydrostatic guideway. Findings For solving the step response, the linear spring-damper model and the nonlinear spring-damper Model 1 are better than the nonlinear spring-damper Model 2. The accuracy of the three methods are very high for static stiffness calculation. For the calculation of dynamic stiffness, the nonlinear spring-damper Model 2 is better than the nonlinear spring-damper Model 1. The linear spring-damper model has low precision for dynamic stiffness calculation, especially at high frequency. The accuracy of the new model is validated by experiments. Originality/value The equivalent method of nonlinear spring-damper system has higher accuracy. Different equivalent methods should be adopted for different load types. The computational speeds of the new dynamic model with the three methods are much better than finite element method (about ten times).

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Chen, Guo-Ding, Fei Lu, Qiang-Peng Yu e Hua Su. "Dynamic analysis of finger seal using equivalent model based on distributed mass method". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, n. 16 (24 febbraio 2014): 2992–3005. http://dx.doi.org/10.1177/0954406214525364.

Testo completo

Abstract (sommario):

Dynamic analysis of finger seal can be performed by finite element method or equivalent model based on lumped mass method now available, which is difficult in meeting both the acceptable calculation time and accuracy simultaneously. For this reason, interactions between finger elements are considered and the equivalent dynamic model based on distributed mass method is proposed in this article. Seal dynamic performances are obtained by using this model to calculate the equivalent parameters, air leakage flow, and the contact behavior between finger seal and the rotor. The work to be presented here concerns the mapping of dynamic behavior of the finger seal with a stack of three finger elements, including the dynamic displacement responses of finger elements, the leakage clearances, and the contact pressures between the finger elements and the rotor, as well as the leakage flow rate and the wear rate. The results calculated by the equivalent model presented in this study are evaluated by comparison with the published experimental data and results from the model based on lumped mass method, which shows that the equivalent model based on distributed mass method is far superior to that based on lumped mass method because the calculations are in good agreement with the experimental results.

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Yang, Jian Xin, Zhen Tao Liu e Jian Wei Sun. "Dynamic Modeling of Overconstrained Parallel Robot". Applied Mechanics and Materials 373-375 (agosto 2013): 34–37. http://dx.doi.org/10.4028/www.scientific.net/amm.373-375.34.

Testo completo

Abstract (sommario):

The dynamic modeling method for parallel robot based on the principle of virtual work and equivalent tree structure is proposed by taking off the platform and the chains as well as degenerating parallel robot into a tree structure, the closed-form solutions for the inverse and forward dynamics models of parallel robot are derived. The method is applied on kinematics and dynamics analysis of a representative 3-RRR spherical parallel robot.

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Fu, Rong, Bao Yun Wang e Wan Peng Sun. "A Coherency-Based Equivalent Model of a Large Scale Wind Farm". Advanced Materials Research 347-353 (ottobre 2011): 2342–46. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.2342.

Testo completo

Abstract (sommario):

With increasing installation capacity and wind farms penetration, wind power plays more important role in power systems, and the modeling of wind farms has become an interesting research topic. In this paper, a coherency-based equivalent model has been discussed for the doubly fed induction generator (DFIG). Firstly, the dynamic models of wind turbines, DFIG and the mechanisms are briefly introduced. Some existing dynamic equivalent methods such as equivalent wind model, variable speed wind turbine model, parameter identification method and modal equivalent method to be used in wind farm aggregation are discussed. Then, considering wind power fluctuations, a new equivalent model of a wind farm equipped with doubly-fed induction generators is proposed to represent the interactions of the wind farm and grid. The method proposed is based on aggregating the coherent group wind turbines into an equivalent one. Finally, the effectiveness of the equivalent model is demonstrated by comparison with the wind farm response obtained from the detailed model. The dynamic simulations show that the present model can greatly reduce the computation time and model complexity.

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Zhang, Yu Mei, Zeng Yao Han, Si Dian Shi e Li Meng Tan. "Validating the New Equivalent Static Design Method of Spacecraft Structures in Random Vibration by Test". Applied Mechanics and Materials 419 (ottobre 2013): 464–69. http://dx.doi.org/10.4028/www.scientific.net/amm.419.464.

Testo completo

Abstract (sommario):

Random vibration is one of dynamic environments of spacecraft during launch. In engineering, design load was usually equivalent static load based on acceleration. A new equivalent static load based on strain or stress was presented by the writer. To validate the new equivalent static design method, random vibration test was designed including test article and test specification, and signal processing was in time domain; static test was designed to compare static yield strength and dynamic yield strength, and dynamic yield strength was 50% -80% higher than static yield strength; measured data in time domain was analyzed , and the equivalent static design of strain based on first passage model can be used to spacecraft structure design. And it will decrease the mass of spacecraft structure obviously.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Wang, Yong, Shunming Li, Chun Cheng e Xingxing Jiang. "Dynamic Analysis of a High-Static-Low-Dynamic-Stiffness Vibration Isolator with Time-Delayed Feedback Control". Shock and Vibration 2015 (2015): 1–19. http://dx.doi.org/10.1155/2015/712851.

Testo completo

Abstract (sommario):

This paper proposes the time-delayed cubic velocity feedback control strategy to improve the isolation performance of High-Static-Low-Dynamic-Stiffness (HSLDS) vibration isolator. Firstly, the primary resonance of the controlled HSLDS vibration isolator is obtained by using multiple scales method. The equivalent damping ratio and equivalent resonance frequency are defined to study the effects of feedback gain and time delay on the primary resonance. The jump phenomenon analysis of the controlled system without and with time delay is investigated by using Sylvester resultant method and optimization method, respectively. The stability analysis of the controlled system is also considered. Then, the 1/3 subharmonic resonance of the controlled system is studied by using multiple scales method. The effects of feedback gain and time delay on the 1/3 subharmonic resonance are also presented. Finally, force transmissibility is proposed to evaluate the performance of the controlled system and compared with an equivalent linear passive vibration isolator. The results show that the vibration amplitude of the controlled system around the resonance frequency region decreases and the isolation frequency band is larger compared to the equivalent one. A better isolation performance in the high frequency band can be achieved compared to the passive HSLDS vibration isolator.

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Chen, Ming, Wenbo Lu, Peng Yan e Chuangbing Zhou. "New method for dynamic stability analysis of rock slope under blasting vibration based on equivalent acceleration and Sarma method". Canadian Geotechnical Journal 51, n. 4 (aprile 2014): 441–48. http://dx.doi.org/10.1139/cgj-2012-0475.

Testo completo

Abstract (sommario):

Dynamic stability of rock slopes under dynamic blasting disturbance and its analytic method are key problems in slope engineering. Based on wave theory, the relationship between blasting vibration velocity, acceleration, and stress state of slopes is studied. The results indicate that with the same blasting vibration velocity, peak stress of the slopes is identical. An equivalent acceleration calculation method is proposed for the limit equilibrium analysis of rock slope stability under blasting vibration. Considering the dynamic time-varying characteristics of the blasting vibration loading, a time-history method based on the equivalent acceleration and the Sarma method of limit equilibrium analysis is then presented for the dynamic stability analysis of rock slopes. On the basis of this new method, the high rock slopes on the left bank in the Jinping I Hydropower Station are analyzed. Results of the case study derived from the new analytic method indicate that this new method is reasonable.

Gli stili APA, Harvard, Vancouver, ISO e altri

24

CHEN, Tao. "Gradient-based Equivalent Static Loads Method for Structure Nonlinear Dynamic Optimization Problem". Journal of Mechanical Engineering 51, n. 8 (2015): 116. http://dx.doi.org/10.3901/jme.2015.08.116.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Kang, B. S., G. J. Park e J. S. Arora. "Optimization of Flexible Multibody Dynamic Systems Using the Equivalent Static Load Method". AIAA Journal 43, n. 4 (aprile 2005): 846–52. http://dx.doi.org/10.2514/1.4294.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Wang, Peng, Zhenyuan Zhang, Qi Huang e Wei-Jen Lee. "Wind Farm Dynamic Equivalent Modeling Method for Power System Probabilistic Stability Assessment". IEEE Transactions on Industry Applications 56, n. 3 (maggio 2020): 2273–80. http://dx.doi.org/10.1109/tia.2020.2970377.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Kontis, Eleftherios O., Theofilos A. Papadopoulos, Mazheruddin H. Syed, Efren Guillo-Sansano, Graeme M. Burt e Grigoris K. Papagiannis. "Artificial-Intelligence Method for the Derivation of Generic Aggregated Dynamic Equivalent Models". IEEE Transactions on Power Systems 34, n. 4 (luglio 2019): 2947–56. http://dx.doi.org/10.1109/tpwrs.2019.2894185.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Zhou, HaiQiang, Ping Ju, Hui Yang e Ran Sun. "Dynamic equivalent method of interconnected power systems with consideration of motor loads". Science China Technological Sciences 53, n. 4 (20 marzo 2010): 902–8. http://dx.doi.org/10.1007/s11431-010-0110-8.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Dong, ShuXiang, e JunYi Zhai. "Equivalent circuit method for static and dynamic analysis of magnetoelectric laminated composites". Science Bulletin 53, n. 14 (luglio 2008): 2113–23. http://dx.doi.org/10.1007/s11434-008-0304-7.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

30

SAKAI, Kimitoshi, Go ARAKI e Yoshitaka MURONO. "EQUIVALENT SINGLE DEGREE OF FREEDOM METHOD FOR NONLINEAR DYNAMIC ANALYSIS OF EMBANKMENT". Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)) 73, n. 1 (2017): 174–86. http://dx.doi.org/10.2208/jscejseee.73.174.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Zhang, Jian, e Xiao Dong Yuan. "Dynamic Aggregation Method of Induction Motors Based on Coherent Characteristics". Advanced Materials Research 960-961 (giugno 2014): 1214–24. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.1214.

Testo completo

Abstract (sommario):

Parameters of induction motors have crucial effects on power system simulation. This paper proposes a dynamic aggregation method of induction motors. In this method, firstly, starting off the electromechanical models of induction motors, taking the coefficients of the electromechanical equations and steady state slips of motors as the characteristic vectors, motors are grouped with fuzzy C-means clustering method. Then, electromechanical equations of the equivalent motor are obtained by averaging that of the individual motors in the same group. Finally, parameters of equivalent motors are calculated based on the relationship of transient impedance before and after aggregation, and the principle that active and reactive power loads are equal before and after aggregation. Simulation results show that the proposed method can improve the precision of simulation

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Tudjono, Sri, e Patria Kusumaningrum. "Dynamic Response of RC Cantilever Beam by Equivalent Single Degree of Freedom Method on Elastic Analysis – A Review on Transformation Factors and Dynamic Magnification Factors". MATEC Web of Conferences 159 (2018): 01005. http://dx.doi.org/10.1051/matecconf/201815901005.

Testo completo

Abstract (sommario):

The response of multi-degree-of-freedom (MDOF) structure can be correlated to the response of an equivalent single-degree-of-freedom (SDOF) system, implying that the response is controlled by a single, unchanged mode shape. This equivalent SDOF method is eminent as an approximate method of dynamic analysis. In this study, equivalent SDOF method analysis is carried out on RC cantilever beam subjected to dynamic blast loading to review the transformation factors (TFs) provided by TM5-1300 code.

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Qu, Yunfei, Dian Wang e Hongye Zhang. "The equivalent method of double V-wing honeycombs on the in-plane dynamic impact". Journal of Reinforced Plastics and Composites 40, n. 15-16 (12 marzo 2021): 577–93. http://dx.doi.org/10.1177/0731684421990867.

Testo completo

Abstract (sommario):

The double V-wing honeycomb can be applied in many fields because of its lower mass and higher performance. In this study, the volume, in-plane elastic modulus and unit cell area of the double V-wing honeycomb were analytically derived, which became parts of the theoretical basis of the novel equivalent method. Based on mass, plateau load, in-plane elastic modulus, compression strain and energy absorption of the double V-wing honeycomb, a novel equivalent method mapping relationship between the thickness–width ratio and the basic parameters was established. The various size factor of the equivalent honeycomb model was denoted as n and constructed by the explicit finite element analysis method. The mechanical properties and energy absorption performance for equivalent honeycombs were investigated and compared with hexagonal honeycombs under dynamic impact. Numerical results showed a well coincidence for each honeycomb under dynamic impact before 0.009 s. Honeycombs with the same thickness–width ratio had similar mechanical properties and energy absorption characteristics. The equivalent method was verified by theoretical analysis, finite element analysis and experimental testing. Equivalent honeycombs exceeded the initial honeycomb in performance efficiency. Improvement of performance and weight loss reached 173.9% and 13.3% to the initial honeycomb. The double V-wing honeycomb possessed stronger impact resistance and better load-bearing capacity than the hexagonal honeycomb under impact in this study. The equivalent method could be applied to select the optimum honeycomb based on requirements and improve the efficiency of the double V-wing honeycomb.

Gli stili APA, Harvard, Vancouver, ISO e altri

34

He, Yansong, Liangsong Chen, Zhongming Xu e Zhifei Zhang. "A Compressed Equivalent Source Method Based on Equivalent Redundant Dictionary for Sound Field Reconstruction". Applied Sciences 9, n. 4 (25 febbraio 2019): 808. http://dx.doi.org/10.3390/app9040808.

Testo completo

Abstract (sommario):

The equivalent source method (ESM) based on compressive sensing (CS) requires that the source has a sparse or approximately sparse representation in a suitable basis or dictionary. However, in practical applications, it is not easy to find the appropriate basis or dictionary due to the indeterminate characteristics of the source. To solve this problem, an equivalent redundant dictionary is constructed, which contains two core parts: one is the equivalent dictionary used in the CS-based ESMs under the sparse assumption, and the other one is the orthogonal basis obtained by the singular value decomposition (SVD). On this foundation, a method named compressed ESM based on the equivalent redundant dictionary (ERDCESM) is proposed to enhance the performances of source field reconstruction for different types of sources. Moreover, inspired by the idea of functional beamforming (FB), ERDCESM with order v (ERDCESM- v ) can possess a high dynamic range when detecting the source location. The numerical simulations are carried out at different frequencies to evaluate the performance of the proposed method, and the results suggest that the proposed method performs well both for sparse and even spatially extended sources. The validity and practicality of the proposed method are also verified by the experimental results.

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Sun, Yuan Gui, Guo Sun e Yuan Jun Gao. "Inverse Identification of Nonlinear Boundary for a Pile Using Time Domain Multi-Point Approximations Method". Applied Mechanics and Materials 670-671 (ottobre 2014): 1167–71. http://dx.doi.org/10.4028/www.scientific.net/amm.670-671.1167.

Testo completo

Abstract (sommario):

A inverse identification method is proposed to deal with the nonlinear boundary parameter identification problem. The boundary condition is modeled as unknown equivalent substructure applied on the initial linear structure and the parameter identification inverse problem is translated into a linear-model based equivalent force identification problem. Based on a given multi-point approximations method, the time history of the equivalent force is identified using the measured dynamic response. The unknown dynamic forces due to substructure are parameterized by combination the base functions on a series of space-time points. Using the moving least squares method, a matrix is derived to extract the force time history from the measured dynamic response. Then, the boundary stiffness and damping are identified using the input-output data of the equivalent substructure. The proposed approach has been demonstrated by some numerical examples and the boundary parameters are successfully identified.

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Chang, Liang-Wey, e J. F. Hamilton. "Simulation of Flexible-Link Manipulators Applying Sequential Integration Method". Journal of Dynamic Systems, Measurement, and Control 113, n. 1 (1 marzo 1991): 175–78. http://dx.doi.org/10.1115/1.2896346.

Testo completo

Abstract (sommario):

The Equivalent Rigid Link System (ERLS) dynamic model offered a complete representation for the dynamics of flexible manipulators. The equations of motion were separated into a nonlinear large motion and a linear small motion. In this paper, a sequential integration method facilitates the solution of the system equations. This method integrates the large (slow) motion equation explicitly and integrates the small (fast) motion equation implicitly. The simulation results are presented to show the computation efficiency and the flexibility effects.

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Zhang, Lei, e Xiangtao Zhuan. "Active Control Method Based on Equivalent Stiffness and Damping Coefficient for an Electromagnetic Isolation System". Applied Sciences 10, n. 22 (10 novembre 2020): 7953. http://dx.doi.org/10.3390/app10227953.

Testo completo

Abstract (sommario):

For improving the performance of an electromagnetic isolation system with reasonable parameters and avoid the parameter tuning problem of a PID controller, an active control method is put forward based on equivalent stiffness and damping coefficient. In this paper, the range of equivalent stiffness coefficient and damping coefficient of the electromagnetic force are calculated based on the required range of dynamic performance indexes. According to the nonlinear expression between electromagnetic force and coil current and gap, the relationships between the coil current and equivalent stiffness coefficient and damping coefficient are established. Then, the equivalent stiffness coefficient and damping coefficient can be satisfied by the controlled current in different gaps for meeting the required dynamic performance indexes. For reducing the maximum overshoot and the number of oscillations of the system, the active control method with the piecewise equivalent stiffness and damping coefficient is proposed based on the piecewise control strategy to realize the variable control parameters of the isolation system. Simulation and experimental results verify that the control method based on the equivalent stiffness and damping coefficient can obtain the desired dynamic performance indexes and the proposed control method with the piecewise strategy can not only reduce the setting time of the system, but also ensure the stability of the system.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Huang, B. C., K. M. Lam, A. Y. T. Leung e Y. K. Cheung. "Equivalent Modal Damping Ratios of a Composite Tube-Type Tall Building to Dynamic Wind Loading". Shock and Vibration 3, n. 2 (1996): 99–105. http://dx.doi.org/10.1155/1996/608684.

Testo completo

Abstract (sommario):

This article discusses computing methods of the equivalent modal damping ratio for a composite tube-type tall building. The equivalent damping ratio of a composite structure under wind-induced vibrations encompasses the combined effects from the different values of damping, mass, and stiffness of the external and internal tubes. A detailed method incorporating Rayleigh damping and the transfer matrix method is proposed for the determination of the equivalent modal damping ratio. A simplified method for engineering applications is also proposed. Results for a 40-story building are presented exemplifying the computation and relationships between the properties of the external and internal tubes.

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Liang, Mingxuan, Ying Wang e Tian Zhao. "Optimization on Nonlinear Dynamics of Gear Rattle in Automotive Transmission System". Shock and Vibration 2019 (24 dicembre 2019): 1–12. http://dx.doi.org/10.1155/2019/4056204.

Testo completo

Abstract (sommario):

Recently, gear rattle noise is gradually becoming a nonignorable issue involving comfortableness in automotive transmission for a car. Generally, the rattle noise is influenced by nonlinear dynamic of multiple pairs of idler gears in the multistage gear transmission system. Optimization methods based on nonlinear rattle dynamic analysis are worthy of further study to control the noise. In this research, an equivalent rattle dynamic model of the idler gear is proposed, and the nonlinear rattle dynamic responses are solved based on the integral method. The effect laws of key factors on nonlinear dynamic performance are investigated by using a bifurcation diagram, spectrum map, and Poincaré map. Finally, the gear backlash, equivalent mass, and rotational speed are optimized based on Kriging surrogate model (KSM) and differential evolution (DE) algorithm by taking the minimization of the maximum rattle noise as the optimal object. It can be concluded that the rattle dynamics of the idler gear show rich nonlinear characteristics as the parameters change. The proposed method can not only reduce the sound pressure level of rattle noise but also provide a viable path and reference value for the low-noise design of the gear transmission system.

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Kong, Xiang Hong, e Zhi Jin Wang. "Thermally Induced Vibration Analysis of Composite Laminate Based on Equivalent Displacement Method". Applied Mechanics and Materials 576 (giugno 2014): 87–93. http://dx.doi.org/10.4028/www.scientific.net/amm.576.87.

Testo completo

Abstract (sommario):

Thermally induced vibration (TIV) of composite laminate subjected to suddenly applied heating is studied using finite element (FE) method in this paper. Some Python programs written by the authors are used to process the data of the analysis flow, and complete the pre- and post-process of FE models used in the four analyses. An equivalent displacement method is proposed to calculate equivalent temperature load. Dynamic responses of six composite laminates with different sizes are analyzed with solid FE models and shell FE models. The results gotten by FE method are in close proximity to that gotten by classic theory and shear theory under certain conditions. It is proved that the TIV analysis method proposed in this paper is reliable and efficient. The TIV analysis with FE method based on equivalent displacement method can solve the dynamic response of a structure due to sudden changes of temperature or suddenly applied heating.

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Carneiro, J. O., F. J. Q. de Melo, J. T. Pereira e V. Teixeira. "Pseudo-Dynamic Method for Structural Analysis of Automobile Seats". Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 219, n. 4 (1 dicembre 2005): 337–44. http://dx.doi.org/10.1243/146441905x52964.

Testo completo

Abstract (sommario):

This work describes the application of a pseudo-dynamic (PsD) method to the dynamic analysis of passenger seats for the automotive industry. The project of such components involves a structural test considering the action of dynamic forces arising from a crash scenario. The laboratory certification of these automotive components consists essentially on the inspection of the propagation and extension of plastic deformations zones in metallic members of the seat structure as consequence of the mutual action between the seat and the passenger fastened to the seat via seat belt anchorages. This work presents a relatively simple experiment using PsD techniques as a novel method to perform a test equivalent to the dynamic model of a dummy-seat pair subjected to impulsive loads from a car crash. Essentially, the PsD test method is a hybrid and hierarchic computer-driven testing procedure where a numerical algorithm and experimental step are used and combined on-line in order to solve a problem in the scope of structural dynamics. The implementation of the method is not expensive and has the leading advantage of offering the operator a total control of any intermediate structure state during the test still keeping the realism of a real dynamic testing.

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Yu, Xiaoyan, Ke-Jun Li, Mingqiang Wang, Zhuo-di Wang, Kaiqi Sun e Jie Lou. "A Multistep Dynamic Equivalent Method for Urban Power Grid Based on District Dividing". IEEE Transactions on Industry Applications 53, n. 2 (marzo 2017): 908–17. http://dx.doi.org/10.1109/tia.2016.2628720.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Hong, Bo, Hanmei Hu, Ting Chen e Qinfeng Li. "Dynamic Equivalent Method of Motor Loads for Power Systems Based on the Weighted". Journal of Power and Energy Engineering 02, n. 04 (2014): 416–22. http://dx.doi.org/10.4236/jpee.2014.24056.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Takayanagi, Motowo, Shinsaku Uemura e Shunsuke Minami. "Application of equivalent model method to dynamic rheo-optical properties of crystalline polymer". Journal of Polymer Science Part C: Polymer Symposia 5, n. 1 (7 marzo 2007): 113–22. http://dx.doi.org/10.1002/polc.5070050111.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Jiang, Zhihao, Ning Tong, Yilu Liu, Yaosuo Xue e Alfonso G. Tarditi. "Enhanced dynamic equivalent identification method of large-scale power systems using multiple events". Electric Power Systems Research 189 (dicembre 2020): 106569. http://dx.doi.org/10.1016/j.epsr.2020.106569.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Mousavi, Mohsen, e Amir H. Gandomi. "An input–output damage detection method using static equivalent formulation of dynamic vibration". Archives of Civil and Mechanical Engineering 18, n. 2 (febbraio 2018): 508–14. http://dx.doi.org/10.1016/j.acme.2017.01.007.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Wang, Tong, Mingyang Gao, Dengkai Mi, Shilou Huang e Zengping Wang. "Dynamic equivalent method of PMSG-based wind farm for power system stability analysis". IET Generation, Transmission & Distribution 14, n. 17 (4 settembre 2020): 3488–97. http://dx.doi.org/10.1049/iet-gtd.2020.0006.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Cunniff, Patrick F., e George J. O’Hara. "Feasibility of a Transient Dynamic Design Analysis Method". Shock and Vibration 1, n. 3 (1994): 241–51. http://dx.doi.org/10.1155/1994/157543.

Testo completo

Abstract (sommario):

This article addresses the degree of success that may be achieved by using simple equipment–vehicle models that produce time history responses whose equipment fixed base modal maximum response values are equivalent to those found in the U.S. Navy's dynamic design analysis method. The criteria of success is measured by a comparison of the results with typical interim shock design values. The equipment models reported are limited to two- degree and three degrees of freedom systems; the model of the vehicle to which the equipment is attached consists solely of a rigid mass and an elastic spring; and the shock excitation is produced by an ideal impulse that is applied to the vehicle mass.

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Wang, Rui, Hao Zhang, Xian Sheng Li, Xue Lian Zheng e Yuan Yuan Ren. "Vehicle Dynamics Model Establishing and Dynamic Characteristic Simulation". Applied Mechanics and Materials 404 (settembre 2013): 244–49. http://dx.doi.org/10.4028/www.scientific.net/amm.404.244.

Testo completo

Abstract (sommario):

By establishing bus simplify coordinate system model and equivalent mechanical model, inertial forces and external forces are analyzed through vehicle lateral movement and vehicle's yaw motion and roll motion. Three degrees of freedom linear motion equation of vehicle is established taking into account lateral motion, yawing movement and rolling motion of vehicle and it can be solved by using method of state space equation. Vehicle dynamic characteristics are analyzed by using this method and programming with Matlab. Vehicle in steering wheel angle step response is analyzed under the conditions of different tire wheel cornering stiffness, moment of inertia, height of center of mass. The results show that increasing rear wheel cornering stiffness, reducing front wheel cornering stiffness and center of mass height, which can effectively improve stability of vehicle. Simulation results provide a theoretical basis and reference for the selection and design of vehicle.

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Chen, S. L., e M. Géradin. "Dynamic Force Identification for Beamlike Structures Using an Improved Dynamic Stiffness Method". Shock and Vibration 3, n. 3 (1996): 183–91. http://dx.doi.org/10.1155/1996/134507.

Testo completo

Abstract (sommario):

In this study a procedure of dynamic force identification for beamlike structures is developed based on an improved dynamic stiffness method. In this procedure, the entire structure is first divided into substructures according to the excitation locations and the measured response sites. Each substructure is then represented by an equivalent element. The resulting model only retains the degree of freedom (DOF) associated with the excitations and the measured responses and the DOF corresponding to the boundaries of the structures. Because the technique partly bypasses the processes of modal parameter extraction, global matrix inversion, and model reduction, it can eliminate many of the approximations and errors that may be introduced during these processes. The principle of the method is described in detail and its efficiency is demonstrated via numerical simulations of three different structures. The sensitivity of the estimated force to random noise is discussed and the limitation of the technique is pointed out.

Gli stili APA, Harvard, Vancouver, ISO e altri

Articoli di riviste sul tema "Dynamic equivalent method"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili