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In this study dynamic responses of a 10 MW offshore wind turbine supported by a multi-body floating platform that consists of a wide cylindrical platform and a cylindrical ballast body suspended by six tendons are analyzed and predicted for different tendon breakage scenarios. A newly-developed and validated fully coupled numerical tool (F2A) based on AQWA and FAST is used to perform aero-hydro-servo-elastic analysis of the floating offshore wind turbine (FOWT). The results indicate that the dynamic behavior of the platform is heavily influenced by the state of tendons health. Roll and yaw motions of the platform under a tendon breakage are found to experience 6 times magnitude amplification of the typical responses, depending on the specific environmental conditions considered. Moreover, the peak tension in the tendon adjacent to the broken tendon experienced an increase of 165% in magnitude. The collective-pitch mode of the platform and wave excitation that are the main contributors to the surge and pitch fluctuations are slightly affected by tendon breakages. The influence of tendon breakages is found to be only significant on the local-pitch and coupled-pitch modes of the platform. In addition, multifractal spectra of the platform accelerations under different tendon failure scenarios show distinct fractal characteristics that can effectively identify and diagnose tendon failures, which is essential to the development of a structural health monitoring system of FOWTs.

The work presented herein sets out to investigate experimentally, via drop-weight testing, the behavior of slender reinforced concrete (RC) beam specimens under impact loading. During testing, the behavior of each specimen is established through the combined use of conventional instrumentation and a high-speed video camera. The primary objective of this work is to investigate the reasons that trigger the observed shift in specimen behavior (compared to that established from static tests) with increasing levels of applied loading rate and intensity. Analysis of the test data reveals that during drop-weight testing only a portion of the element span reacts to the applied load (as indicated by the deformation and cracking profiles recorded) which in turn affects the mechanics underlying specimen behavior and therefore, significantly influencing the mode of failure ultimately exhibited. The observed localized response becomes more prominent by increasing the loading rate and intensity of the imposed impact loading. In addition to the above, the strain-rate sensitivity of the material properties of concrete does not appear to have a significant effect on the behavior of the specimens tested. The aforementioned observations appear to be in conflict with current design practice raising questions concerning the effectives of the design solutions produced.

Earth-rock dam plays an important role in water conservancy project, but there were many damage cases caused by earthquakes, so it is necessary to investigate dynamic responses of earth-rock dams under combined action of earthquake and wave. Considering material nonlinearity, seepage, wave action, fluid-solid interaction, liquid sloshing, a numerical calculation model is established, and Arbitrary Lagrange Eulerian method is used to solve the nonlinear dynamic coupling problem. Dynamic responses under wave, earthquake and wave+earthquake are studied comparatively, and influences of near and far field earthquakes and PGA on dynamic responses are investigated. Results show that values and distributions of dynamic responses under wave and earthquake are quite different, and dynamic responses were further increased considering combination of earthquake and wave. Dynamic responses under far field long period earthquake is significantly larger than that under near field earthquake. With the increase of PGA, increase trends of horizontal displacement, vertical displacement and plastic strain are increased, while increase trend of maximum shear stress is slowed down. It can be obtained that when earthquake intensity is large, earth-rock dam will be easily damaged due to excessive deformation.

This study presents a dynamic model of a passenger vehicle and analyzes its dynamic characteristics and responses. A dynamic vehicle model with seven degrees of freedom was established to analyze the behavior of a driving vehicle. The vehicle model had three degrees of freedom for the sprung mass’s motion and four degrees for the unsprung masses. For this model, the equations of motion were derived using Lagrange’s equation. To verify the model, the suspension deformations computed using the model were compared with those measured through three actual vehicle driving tests: the slalom, double lane change, and step steer tests. Furthermore, we investigated the effects of suspension stiffness, suspension damping, and anti-roll bar torsional stiffness on the dynamic characteristics and responses of the vehicle model. This study presented a new full-car model that can analyze a turning vehicle’s behavior in response to changes in the steering angle input. The developed dynamic vehicle model may help vehicle designers predict the dynamic responses of a vehicle through simulation without performing a driving test.

The concrete-filled double steel tube (CFDST) has been more and more widely used in infrastructure due to its greater moment of inertia compared to the ordinary concrete-filled steel tube (CFST). With the increase in collision accidents occurring in recent years, the research on CFDST under impact needs more attention. To study the dynamic responses of CFDST columns under lateral impact, the finite element package ABAQUS was used to simulate the impact force and mid-span deflection of the column under the coupling action of axial force and lateral impact based on the comparison of experimental data in the literature. The influence of hollow ratio, axial compression ratio, slenderness ratio, impact energy, and material strength on the dynamic responses of the CFDST column are studied. The results show that with the increase in the hollow ratio from 0.3 to 0.8, the residual mid-span deflection of the CFDST column decreases by 77.9%. The mid-span deflection shows an increasing trend following a decreasing one with the axial compression ratio increasing. With the increase in the slenderness ratio from 30 to 60, the plateau impact force decreases by 62.5%, and the residual mid-span deflection increases by 240.5%. The practical formulas for the impact-bearing capacity and residual mid-span deflection of the CFDST column are suggested with high accuracy.

This study proposes a fault-tolerant matrix-converter-controlled IPMSM-drive system, in which a predictive speed-loop controller and a predictive current-loop controller are implemented to improve its dynamic responses, including transient responses and load disturbance responses of the IPMSM-drive system in both normal and faulty conditions. In addition, a sliding-mode estimator is used to estimate the rotor position, rotor speed, and stator currents of the IPMSM when the encoder or current sensor in the IPMSM-drive system is faulty. As a result, the IPMSM-drive system allows for either an encoder fault or a Hall-effect sensor fault. The detailed fault detection, diagnosis, and control are discussed here. In case of an encoder fault or a Hall-effect current sensor fault, the IPMSM-drive system still functions. A digital signal processor, TMS 320LF2407A, is used as a control centre to execute the fault-tolerant algorithm, state-estimating algorithm, and control algorithm. Experimental results can validate the correctness and feasibility of the proposed fault-tolerant and predictive control methods.

Composed of metallic layers and composite plies, fiber metal laminates (FMLs) combine inherent advantages of metals and composites. The phenomenon of anomalous response behavior, in which the permanent deformation is in the opposite direction to the incoming pressure wave, has been discovered in dynamic responses of monolithic plate subjected to impulsive loading. In this study, dynamic responses of FML plates of various configurations are examined and compared against the responses of a monolithic plate using finite element analysis. It is found that under the load condition in which an anomalous dynamic behavior of an aluminum plate is observed, FMLs oscillate a few cycles before resting on permanent deformation, and the laminate thickness strongly affects the final deflection, which could be in the counter-intuitive direction or near the initial position of zero deflection depending on configuration and specification of FMLs. In addition, interaction of damage accumulation with deflection responses is investigated. The findings of this study can be useful for optimal design of FMLs intended for usage under extreme loadings.

Overloaded truck and earthquake have become two main factors responsible for bridge damage, consequently the combination of heavy truck and seismic loads as a typical occurrence of extreme events is likely to lead to bridge collapse or destructive damage, in which the crucial issues of coupling load model, dynamic equations and bridge responses have not been adequately addressed. In this study, a simplified vehicle-bridge model consisting of many containers is established to simulate vehicle passage, and the dynamic equations are derived for a 5-axle truck on a simply supported beam as an illustration. Then, five ground motions selected from PEER with appropriate peak ground accelerations and durations and the three truck models specified in American Association of State Highway and Transportation Officials, Caltrans and Chinese codes are applied on the finite element model of a typical reinforced concrete continuous girder bridge, in which, vehicle speed, number of trucks, ground motion and vehicle type are assumed to be random variables and their influences on dynamic responses of the bridge are analyzed. The results show seismic load is the governing factor in dynamic responses but truck load may change displacement shapes; in addition, dynamic responses present a high sensitivity with the number of trucks (set as truck platoon) and gross vehicle weight but rare with vehicle speed. Specifically, the presence of a few trucks could serve as energy dissipation facilities for the bridge under seismic motions but may amplify the response when more trucks involved; some combinations of truck platoon with seismic excitation produce very large displacements and even cracks on the bridge, therefore, such an extreme event requires higher robustness in bridge design to make it be sustainable and serviceability after earthquakes.

Under strong winds, the effect of sudden windbreak transition (WT) on high-speed trains is severe, leading to a deterioration of train aerodynamics and sudden yawing motion of the car body. To address these problems, based on a high-speed train and the specific geometric conditions derived from Xinjiang railway, first, the impact of a WT on the train and reasons for sudden changes in aerodynamic forces were determined by flow structural analysis. Furthermore, based on a multibody system dynamic model, the dynamic responses to WT were analysed. The results show that the impacts of WT were the strongest on the head car. WT had a strong effect on the train due to the unreasonable structural shape and the insufficient height of the windbreak in the transition region. This led to a strong push effect on the train; subsequently, the train’s dynamic characteristics deteriorated.

The design of aircraft hydraulic pipeline system is limited by many factors, such as the integrity of aviation structure or narrow installation space, so the limited clamp support position should be considered. This paper studied the frequency adjustment and dynamic responses reduction of the multi-support pipeline system through experiment and numerical simulation. To avoid the resonance of pipeline system, we proposed two different optimization programs, one was to avoid aero-engine working range, and another was to avoid aircraft hydraulic pump pulsation range. An optimization method was introduced in this paper to obtain the optimal clamp position. The experiments were introduced to validate the optimization results, and the theoretical optimization results can agree well with the test. With regard to avoiding the aero-engine vibration frequency, the test results revealed that the first natural frequency was far from the aero-engine vibration frequency. And the dynamic frequency sweep results showed that no resonance occurred on the pipeline in the engine vibration frequency range after optimization. Additionally, with regard to avoiding the pump vibration frequency, the test results revealed that natural frequencies have been adjusted and far from the pump vibration frequency. And the dynamic frequency sweep results showed that pipeline under optimal clamp position cannot lead to resonance. The sensitivity analysis results revealed the changing relationships between different clamp position and natural frequency. This study can provide helpful guidance on the analysis and design of practical aircraft pipeline.

Cables have been increasingly utilized in modern long-span or tied-arch bridges as the main bearing structures. Real-time identification of time-varying cable tension is essential for assessing the service performance of bridges. Vibration-based methods have been an increasing research focus in recent decades. However, a long time interval is needed to estimate structural frequency using vibration-based methods, increasing the calculating time of cable tension. The time-varying cable tension is thus difficult to extract. This study proposes a time-frequency reassignment-based algorithm to reduce the detection time to address this issue. Combined with a time-frequency analysis tool and vibration theory of cables, the algorithm can identify the time-varying frequency and further quickly calculate the time-varying cable tension within 12.8 s. The features of the proposed algorithm are mainly threefold: identifying the time-varying frequencies with high precision; without some prior knowledge of vibration; having no other requirements for sensor modes. Moreover, the experimental validation is conducted using a quasi-static loading in a workshop and a dynamic field test on Sutong Bridge, respectively. The results show that the proposed algorithm can be used to identify time-varying tension and assess the service performance of cables, providing a new path for real-time condition monitoring of bridges in service.

Aiming for integration of a large-scale of distributed generators (DGs) such as photovoltaic into the microgrids, the virtual synchronous generator (VSG) control concept has been developed. By this concept, DGs based on inverters can exhibit the characteristics of synchronous generators (SGs) such as the inertial, damping, and droop functions and can participate in the microgrid control and stability. Here, a detailed VSG model is presented and analysed in order to investigate that, VSGs have really the similar structure of SGs. Then, the paper studies the microgrid with both VSG and ordinary SG. Then, parallel arrangements of VSG-VSG are set up in order to compare the dynamic behaviour of the VSG with the standard SG in an isolated microgrid. The dynamic responses are compared under equal sharing and proportional sharing of the load demand. Simulation results are presented using matlab/simulink.

Generating high actuation frequency (∼1.0 kHz) is one of the potential applications of Magnetic Shape Memory Alloys (MSMAs). In this work, dynamic responses of single crystal MSMAs due to variant reorientation are investigated. Time dependent part of the Maxwell equations becomes significant for a high frequency regime. Generation of an electric field and magnetic flux linkage due to the motion of the material points during deformation create a complex electro-magneto-mechanical coupling mechanism. We perform a thermodynamically consistent study to capture the variation of electromagnetic fields due to the deformation in the presence of fluctuating magnetic field, mainly focusing on eddy current and Joule heating. A comparison of MSMA responses with a typical ferromagnet/magnetostrictive material responses is discussed.

With emphasis on long-span bridges, the dynamic responses of bridges without considering random traffic flows were found to be different from actual situations. The introduction of a random traffic flow model provides a new approach for the random analysis of bridge structure responses under vehicle loads. In this paper, the finite element and intelligent ant colony optimization-back propagation neural network (ACO-BPNN) models were used to study the dynamic responses of long-span bridges. The computational model was also validated by an experimental test. To confirm the validity of the proposed ACO-BPNN model after parameter selection, it was compared with the traditional back propagation neural network (BPNN) model and the genetic algorithm-back propagation neural network (GA-BPNN) model. BPNN, GA-BPNN, and ACO-BPNN adopt the same network topology structure to predict the dynamic responses of the long-span bridge. When the ACO-BPNN model conducted the iteration to the 130th generation, a training error of 0.009 was found to be smaller than the set critical error. In this manner, the computational accuracy was increased, and the optimized time was reduced. In addition, only 0.4 hours were spent in using the proposed ACO-BPNN model to predict the dynamic response of the long-span bridge. In the case of the same computer performance, it took 4.5 h to use the finite element model to predict the dynamic response of the long-span bridge. The advantage of the proposed ACO-BPNN model in predicting the performance of large-scale complex structures such as long-span bridges was clearly found.

A train–bridge coupling vibration model for low-speed maglev traffic was established to study the dynamic response of low-medium speed Maglev Train and simply supported beam interation system. In this model, the vehicle is assumed as a secondary suspension mass-spring-damper model with 12 degrees of freedom. The finite element model is supplied to simulate the bridge structure. The influence of the track irregularity is also taken into account. Then, the program for vertical coupling vibration simulation of low-speed maglev traffic is developed. Finally, a field test was carried out on a 25-m simply supported beam in a low-speed maglev test line. The results show that the fundamental frequency, the vibration mode, the mid-span dynamic deflection and the acceleration of the track beam measured values are slightly smaller than the simulation results. When the maglev train passes the simply supported beam, the measured acceleration values of the vehicle are slightly less than the simulation ones. These research results show that the vertical coupling vibration model of low-speed maglev train–track beam is reasonable and the simulation results are credible. With the increase of speed, the accelerations of the bridge and car body are increased in the overall trend. But, the acclerations of the bridge and the maglev car body are both small versus the speed, wich indicates that the dynamic performanceof the bridge and maglev train are good.

The ability to automatically assess emotional responses via contact-free video recording taps into a rapidly growing market aimed at predicting consumer choices. If consumer attention and engagement are measurable in a reliable and accessible manner, relevant marketing decisions could be informed by objective data. Although significant advances have been made in automatic affect recognition, several practical and theoretical issues remain largely unresolved. These concern the lack of cross-system validation, a historical emphasis of posed over spontaneous expressions, as well as more fundamental issues regarding the weak association between subjective experience and facial expressions. To address these limitations, the present paper argues that extant commercial and free facial expression classifiers should be rigorously validated in cross-system research. Furthermore, academics and practitioners must better leverage fine-grained emotional response dynamics, with stronger emphasis on understanding naturally occurring spontaneous expressions. We posit that applied consumer research might be better situated to examine facial behavior in socio-emotional contexts rather than decontextualized, laboratory studies, and highlight how AHAA can be successfully employed in this context. Also, facial activity should be considered less as a single outcome variable, and more as promising input for two-step machine learning in combination with other (multimodal) features. We illustrate this point in a case study using facial activity as input features to predict crying behavior in response to sad movies. Implications of this approach and potential obstacles that need to be overcome are discussed within the context of consumer research.

The current research of wind turbine drivetrain is mainly concentrated in dynamic characteristics of gearbox with a specific suspension of main shaft, such as one-point and two-point suspension. However, little attention is paid to the effects of these suspension configurations on the dynamic responses of wind turbine gearbox. This paper investigates the influences of suspension configurations of main shaft on the dynamic characteristics of drivetrain. For evaluating the dynamic behaviors of drivetrain with multi-stage transmission system more realistically, a dynamic modeling approach of drivetrain is proposed based on Timoshenko beam theory and Lagrange’s equation. Considering the flexibility and different suspension configurations of main shaft, time-varying mesh stiffness excitation, time-varying transmission error excitation and gravity excitation, etc., a three-dimensional dynamic model of drivetrain is developed, and the dynamic responses of drivetrain are investigated. Results show that with the one-point suspension of main shaft, the resonance frequencies in gearbox, especially at the low-speed stage, obviously shift to the higher frequency range compared to the gearbox without main shaft, but this trend could be inversed by increasing main shaft length. Meanwhile, the loads in main shaft, main shaft bearing and carrier bearing are greatly sensitive to the main shaft length. Hence, the load sharing is further disrupted by main shaft, but this effect could be alleviated by larger load torque. Comparing to the one-point suspension of main shaft, there occurs the obvious load reduction at the low-speed stage with two-point suspension of main shaft. However, those advantages greatly depend on the distance between two main bearings, and come at the expense of increased load in upwind main shaft unit and the corresponding main bearing. Finally, a wind field test is conducted to verify the proposed drivetrain model. This study develops a numerical model of drivetrain which is able to evaluate the effects of different suspension configurations of main shaft on gearbox.

To explore the influences of subgrade form and ground stiffness on subgrade dynamic responses under train loading, and thus to optimize the design of railway subgrade, this paper presents field tests of cyclic loading for railway subgrade with different ground stiffness of fill sections and different forms of fill and cut sections. The considered comparisons of dynamic responses included the distribution of dynamic stress in railway subgrade, and the elastic deformation, dynamic stiffness, and cumulative plastic deformation on subgrade surface. Gathered data showed that when fill sections were relatively high (more than 6.0m in this study), the ground stiffness showed insignificant influence on the dynamic responses of railway subgrade. For the comparisons of fill and cut sections, the dynamic stiffness on subgrade surface for a cut section was approximately a half of the one for a fill section, but the cumulative plastic deformation was essentially the same for the fill and cut sections. These results provide references for the optimization design of railway subgrade.

A wind-vehicle-bridge system can be regarded as an interaction resuit of wind-bridge interaction, wind-vehicle interaction and vehicle-bridge interaction, which is determined by nature wind, dynamic characteristics of vehicle and bridge structures, interrelationship between bridge and vehicle dynamic properties and so on. Firstly, based on the traffic loading investigation on the expressway bridge within 24 hours a day, and the critical parameters of traffic flow, such as the vehicle type, weight, separation space and speed are and recorded and analyzed to extract its statistical characteristics, which are used to work out random traffic flow simulation program RTF. This RTF program can be embedded with the other general HEM software. Secondly, a dynamic analysis module RTFWVB of the wind-vehicle-bridge coupling vibration under random traffic flow is presented, which can consider arbitrary number of vehicles, multi-lanes and traffic flow direction. Finally, Hangzhou Bay Bridge in China is selected as a numerical example to demonstrate dynamic interaction of the RTFWVB system. The results indicate that the traffic flow direction has just a little influence on bridge dynamic response, that the mean responses are mainly determined by the moving vehicle loads, and that the fluctuating components will increase with the increase of wind speed.

With the development of offshore wind energy in China, more and more offshore wind turbines are being constructed in rock-based sea areas. However, the large diameter and thin-walled steel rock-socketed monopiles are very scarce at present, and both the construction and design are very difficult. For the design, the dynamic safety during the whole lifetime of the wind turbine is difficult to guarantee. Dynamic safety of a turbine is mostly controlled by the dynamic impedances of the rock-socketed monopile, which are still not well understood. How to choose the appropriate impedances of the socketed monopiles so that the wind turbines will neither resonant nor be too conservative is the main problem. Based on a numerical model in this study, the accurate impedances are obtained for different frequencies of excitation, different soil and rock parameters, and different rock-socketed lengths. The dynamic stiffness of monopile increases, while the radiative damping decreases as rock-socketed depth increases. When the weathering degree of rock increases, the dynamic stiffness of the monopile decreases, while the radiative damping increases.

Instrumentation and methods for rapid screening and selection of plants with improved water use efficiency are essential to address current issues of global food and fuel security. A new imaging system that combines chlorophyll fluorescence and thermal imaging has been developed to generate images of assimilation rate (A), stomatal conductance (g s), and intrinsic water use efficiency (WUEi) from whole plants or leaves under controlled environmental conditions. This is the first demonstration of the production of images of WUEi and the first to determine images of g s from themography at the whole-plant scale. Data are presented illustrating the use of this system for rapidly and non-destructively screening plants for alterations in WUEi by comparing Arabidopsis thaliana mutants (OST1-1) that have altered WUEi driven by open stomata, with wild-type plants. This novel instrument not only provides the potential to monitor multiple plants simultaneously, but enables intra- and interspecies variation to be taken into account both spatially and temporally. The ability to measure A, g s, and WUEi progressively was developed to facilitate and encourage the development of new dynamic protocols. Images illustrating the instrument’s dynamic capabilities are demonstrated by analysing plant responses to changing photosynthetic photon flux density (PPFD). Applications of this system will augment the research community’s need for novel screening methods to identify rapidly novel lines, cultivars, or species with improved A and WUEi in order to meet the current demands on modern agriculture and food production.

In this paper, the dynamic response of an infinite plate resting on an elastic foundation subjected to moving traffic load with variable velocity (accelerating or decelerating) is investigated by using a triple Fourier integral transform in time and space. The effects of the load varying velocity, acceleration and deceleration, are discussed respectively. The numerical results indicate that the main affecting parameters are initial velocity, acceleration or deceleration. Numerical examples are presented to compare the results of static analysis and those of dynamic analysis with a constant, varying velocity. The results show that the dynamic response of rigid pavement under a moving traffic load with variable velocity is not only different from that caused by static load, but also different from that generated by load with a constant moving speed. Displacement of the plate is reduced with increasing the varying velocity and acceleration. But, stresses of the plate increase with the varying velocity at given acceleration.

European labour markets have undergone several important innovations over the last three decades. Most countries have reformed their labour markets since the mid-1990s, with the liberalization of fixed-term contracts and temporary work agencies being the common elements to such reforms. This paper investigates the existence of a change in the dynamic behaviour of the aggregate employment for major European Union countries - France, Germany, Italy, and Spain. According to our results, national labour market reforms have made the response of the aggregate employment to output shocks larger and quite comparable to that found for the UK - the most flexible labour market in Europe since the Thatcher reforms.

The dynamic responses is very important characteristic quay crane.Container transportation is the worldwide used and deeply change the style of international trade and economy. The quay crane can significantly increase the efficiency of unload container vessel. This paper focuses on the dynamic responses of the quay crane (or QC for short). The objective is to figure out the real dynamic responses and of QC. We present the efficiently method compute dynamic responses by the virtual prototype technology [1] . The QC is modeled by software ADMAS and the simulation results are verified by the experiments. It can provide a direction to decrease the dynamic responses of QC [2] .

In order to represent the mechanical response laws of high-modulus asphalt pavement (HMAP) faithfully and objectively, the viscoelasticity of high-modulus asphalt mixture (HMAM) was considered, and the viscoelastic mechanical responses were calculated systematically based on moving load by numerical simulations. The performances of the HMAP in resistance to the deformation and the cracking at the bottom layer were compared with the ordinary asphalt pavement. Firstly, Lubao and Honeywell 7686 (H7686) were selected as the high modulus modifiers. The laboratory investigations of Asphalt mix-70 penetration, Asphalt mix-SBS (styrene-butadiene-styrene), HMAM-Lubao and HMAM-H7686 were carried out by dynamic modulus tests and wheel tracking tests. The conventional performances related to the purpose of using the HMAM were indicated. The master curves of the storage moduli were obtained and the viscoelastic parameters were fitted based on viscoelastic theories. Secondly, 3D pavement models based on moving loads for the viscoelastic structures were built using the non-linear finite element software ABAQUS. The wheel path was discretized in time and space to apply the Haversine wave load, and then the mechanical responses of four kinds of asphalt pavement were calculated. Finally, the sensitivity analysis was carried out. The results showed that the addition of the high modulus modifiers can improve the resistance to high-temperature rutting of the pavements. Except for the tensile strain and stress at the bottom of the underlayer, other responses decreased with the increases of the dynamic moduli and the change laws of the tensile strain and stress were affected by the range of the dynamic modulus. The tensile stress at the bottom of the asphalt layer would be too large if the modulus of the layer were too large, and a larger tensile strain would result. Therefore, the range of the modulus must be restricted to avoid the cracking due to excessive tension when using the HMAM. The resistance of the HMAP to deformation was better and the HMAP was less sensitive to load changes and could better withstand the adverse effects inflicted by heavy loads.

This paper deals with the dynamic behaviour of cold-formed steel hollow frames with different connection stiffnesses. An analytical model of a semi-rigid frame was developed to study the influence of connection stiffnesses on the fundamental frequency and dynamic response of the frames. The flexibilities of the connections are modeled by rotational springs. Neglect of semi-rigidity leads to an artificial stiffening of frames resulting in shorter fundamental period, which in turn results in a significant error in the evaluation of dynamic loads. In the seismic design of structures, of all the principal modes, the fundamental mode of translational vibration is the most critical. Hence, experiments were conducted to study the influence of the connection stiffnesses on the fundamental mode of translational vibration of the steel hollow frames. From the experimental study it was found that the fundamental frequency of the frames lie in the semi-rigid region. From the theoretical investigation it was found that the flexibly connected frames subjected to lateral loads exhibit larger deflection as compared to rigidly connected frames.

Environmental and sustainability concerns are developing the significance of distributed generation (DG) based on renewable energy sources. In this paper, dynamic responses investigation of grid connected wind turbine using permanent magnet synchronous generator (PMSG) under variable wind speeds and load circumstances is carried out. In order to control of turbine output power using Fuzzy Logic controller (FLC) in comparison with PI controller is proposed. Furthermore, the pitch angle based on FLC using wind speed and active power as inputs, can have faster responses, thereby leading to smoother power curves, enhancement of dynamic performance of wind turbine and prevention of mechanical damages to PMSG. Inverter adjusted the DC link voltage and active power is fed by d-axis and reactive power is fed by q-axis (using P-Q control mode). Simulation of wind power generation system (WPGS) is carried out in Matlab/Simulink, and the results verify the correctness and feasibility of control strategy.

Design of crash dummies and development of numeric models of the human body require data sets which specify the performance of real humans in crash impact conditions. Rear impact conditions have become increasingly important during the last decade. This resulted in a growing number of research projects focusing on the kinematic and dynamic response of the human body. A test and analysis methodology and procedure to set up these types of tests to establish a set of response parameters are presented in this chapter. Choice of instrumentation, film techniques, and data processing are discussed. An example of anthropometry measures required for further analysis is presented. A three-linkeage mechanism, as an analog used to define response parameters, is introduced. In the past, analysis was limited to head and neck for forward impacts, but this needs to be extended to include the spine and pelvis for rear impact conditions as the interaction of car seat and body cannot be omitted. The response corridors developed from a series of volunteer tests are presented as an illustration of a data set to be used for dummy and numeric model evaluation. The methodology presented here and the specified response parameters can be used for any rear impact full body test and would make it possible to combine results of several research projects which could create a growing database.

Design of crash dummies and development of numeric models of the human body require data sets which specify the performance of real humans in crash impact conditions. Rear impact conditions have become increasingly important during the last decade. This resulted in a growing number of research projects focusing on the kinematic and dynamic response of the human body. A test and analysis methodology and procedure to set up these types of tests to establish a set of response parameters are presented in this chapter. Choice of instrumentation, film techniques, and data processing are discussed. An example of anthropometry measures required for further analysis is presented. A three-linkeage mechanism, as an analog used to define response parameters, is introduced. In the past, analysis was limited to head and neck for forward impacts, but this needs to be extended to include the spine and pelvis for rear impact conditions as the interaction of car seat and body cannot be omitted. The response corridors developed from a series of volunteer tests are presented as an illustration of a data set to be used for dummy and numeric model evaluation. The methodology presented here and the specified response parameters can be used for any rear impact full body test and would make it possible to combine results of several research projects which could create a growing database.