Dynamic Response

The principal concerns in driving safety with standard vehicles or cybercars are understanding and preventing risky situations. A close examination of accident data reveals that losing control of the vehicle is the main reason for most car accidents. To help to prevent such accidents, vehicle-control systems may be used, which require certain input data concerning vehicledynamic parameters and vehicle-road interaction. Unfortunately, some fundamental parameters, like tire-road forces and sideslip angle are difficult to measure in a car, for both technical and economic reasons. Therefore, this study presents a dynamic modeling and observation method to estimate these variables. One of the major contributions of this study, with respect to our previous work and to the largest literature in the field of the lateral dynamic estimation, is the fact that lateral tire force at each wheel is discussed in details. To address system nonlinearities and unmodeled dynamics, two observers derived from extended and unscented Kalman filtering techniques are proposed and compared. The estimation process method is based on the dynamic response of a vehicle instrumented with available and potentially integrable sensors. Performances are tested using an experimental car. Experimental results demonstrate the ability of this approach to provide accurate estimations, and show its practical potential as a low-cost solution for calculating lateral tire forces and sideslip angle.

Orchestrated modulation of cell adhesion is essential for development and homeostasis in multicellular organisms. It optimizes embedding of the cell in its dynamic environment and facilitates appropriate cell responses and intercellular communication. Chronic disturbance of this delicate equilibrium causes defects in tissue architecture and sometimes cancer. In tumor cell biology, dynamic control of adhesion molecules is important to proceed through the metastatic cascade and to allow cell release from the primary tumor, invasion of the surrounding matrix, intravasation and adhesion to vascular endothelial cells to facilitate extravasation. Intertwined and multiple adhesive interactions rather than individual interactions presumably play critical roles in neoplastic development. Yet, knowledge of the contribution of each individual adhesion molecule is essential to unravel this network of interactions. This review will focus on activated leukocyte cell adhesion molecule (ALCAM/CD166) and its role in human melanoma progression. It is hypothesized that ALCAM may function as a cell surface sensor to register local growth saturation and to regulate cellular signaling and dynamic responses.

The optimum parameters of multiple tuned mass dampers (MTMD) for suppressing the dynamic response of a base-excited structure in a specific mode is investigated. The base excitation is modelled as a stationary white noise random process. The stationary response of the structure with MTMD is analyzed for the optimum parameters of the MTMD system. The criterion selected for optimality is the minimization of the root mean square (r.m.s.) displacement of the main structure. The parameters of MTMD that are optimized include the damping ratio, the tuning frequency ratio and the frequency bandwidth of the MTMD system. The optimum parameters of the MTMD system and corresponding effectiveness are obtained for different damping ratios of the main structure and mass ratios of the MTMD system. In addition, the effectiveness of an optimally designed MTMD system is compared with that of an optimum single tuned mass damper. It is shown that the optimally designed MTMD system is more effective for ...

The aim of this paper is to present a new fuzzy control scheme for real time drive efficiency improvement by the adaptive flux reduction at light loads during steady states and by the optimum flux recovery during transient states. The optimum flux recovery instead of the rated flux does not sacrifice the drive dynamic response since the torque capacity remains the same and accelerates the search convergence in steady states. The control scheme is cooperated with an Indirect-Field-Oriented-Control (IFOC) motor drive. The design of the new fuzzy control scheme is focused to recognize the motor state operation in order to control under the corresponding circumstances. The proposed fuzzy control scheme includes three main units: one Fuzzy-Logic-Search Controller FLSC1, one Fuzzy-Logic-Controller FLC2 and a State detector unit. The State detector unit decides which of the FLSC1 or FLC2 controllers is used, in accordance to the operation circumstances. The fuzzy controllers utilize the stator flux-producing current component into d-q reference frame (stator current direct axis i sd) as control variable, in order to estimate the next optimal change of Δi sd. The drive efficiency improvement and the drive dynamic response is currently validated in laboratory using an experimental array of a 3phase 1 Hp induction motor drive. The control scheme is implemented using the platform eZdsp from Digital Spectrum based on the fixed point 32 bit DSP TMS320F2812 from TI.

This paper describes an integrated boost-full bridge rectEfier power factor corrector driven by a sliding-mode control. Due to the sliding-mode control, fast regulation of the output voltage is achieved. In addition, with this scheme, the major power goes through a single stage to the output, while both unity power factor and fast dynamic response is obtained, and the eficiency as well as the power density can be higher than in a conventional two cascade stage scheme. A prototype circuit has been built to verijj this approach. The control strategy and experimental results will be presented.

A new method to improve the dynamic response of power-factor correctors (PFC's) is described in this paper. The method is based on the use of a new very highly efficient postregulator, called a series-switching postregulator. This new postregulator exhibits very high efficiency due to the fact that only a part of the total power undergoes a power conversion process. The proposed postregulator can be used with any PFC topology (either with or without a transformer), with no modifications in the topology, and can be easily protected against short circuits.

In this paper, a MATLAB Simulink model for Toyota Prius 2004 hybrid electric vehicle (HEV) is presented. The model is based on MATLAB Simulink HEV model and we covered some of differences between this model and real vehicle and obtain an acceptable model regards to DOE reports.

Transverse vibrations of drillstrings caused by axial loading and impact with the wellbore wall is studied. The drillstring is modeled as a slender beam with a simply-supported lower part. The Assumed Modes Method is used to obtain the governing equations of motion. Non-linear coupling terms are retained in the formulation which leads to full coupling between the axial and transverse vibration modes. The Hertzian contact theory is used to model impacts between the drillstring and the wellbore wall. The governing non-linear equations are solved numerically to obtain the response. Simulation studies are used to compare the dynamic response obtained from both fully coupled and uncoupled models. Significant differences between the two models are observed. The coupled model yields an unstable behavior at a lower load than the uncoupled model, and the subsequent response is not periodic.

Chl-Zr 26 and Chl-ZML relationships. This important role of ocean physics indicates that the observed Chl changes primarily reflect biomass changes due to dampened or increased nutrient fluxes to the upper lit layers. Changes in the photoacclimation state of phytoplankton probably also intervene, without obscuring the global picture, however. Quantifying the respective role of both phenomena would require the parallel examination of Chl and other quantities more directly tied to biomass.

In the framework of the Eu-India Economic Cross Cultural Programme "Improv- ing the Seismic Resistance of Cultural Heritage Buildings", aimed at the preservation of ancient masonry structures with regard to the seismic risk, different NDT were applied to the Qutb Minar, New Delhi, India, in September 2005. The paper describes the different investigation techniques applied (Ambient Vibration and Pulse Sonic

The scope of the paper is to present some aspects of the development of a "macro-element" for dynamic soil-structure interaction analyses of shallow foundations. Initially the concept of "macro-element" is introduced and is illustrated with the aid of a very simple example originating from structural engineering. Then the link is made with the modeling of the dynamic response of shallow

The characterization of the dynamic response (including transfer function identification) of trilayer polypyrrole (PPy) type conducting polymer sensors is presented. The sensor was built like a cantilever beam with the free end stimulated through a mechanical lever system, which provided displacement inputs. The voltage generated and current passing between the two outer PPy layers as a result of the input was measured to model the output/input behavior of the sensors based on their experimental current/displacement and voltage/displacement frequency responses. We specifically targeted the low-frequency behavior of the sensor as it is a relatively slow system. Experimental transfer function models were generated and verified experimentally for sensors with different dimensions. The models can be used to understand the dynamic behavior and sensing ability of the polymers as mechanical sensors. The effect of the active sensor length on the voltage and current outputs has demonstrated that the shorter is the sensor length, the higher are the voltage output and the current passed for the same mechanical input. Also, their current and voltage responses under an impulse displacement stimulus were experimentally measured to show their dynamic sensing response and to estimate the current and voltage sensing bandwidths. Further, an energy balance method has been proposed to estimate the sensor output. Based on the novel experimental and analytical results, the contribution of this study is the first comprehensive investigation into the response analysis and characterization of the PPy-type conducting polymers as mechanical sensors, to the best of authors' knowledge.

A computation and experimental study of dam-water-foundation interaction conducted at Longyangxia Dam in China is described. In the primary tests, the dam and its retained water were excited by detonating large explosive charges in shallow water upstream from the dam. The dam and water responses to the ex- plosives were recorded by accelerometers, pressure sensors, and three-component seismographs. In sec- ondary tests, the average reflection coefficient of the reservoir boundaries was measured using a newly developed procedure based on the acoustic reverberation concept. The results obtained indicate that ex- plosive detonations appear to be the best means for exciting the dam-water-foundation system, and that an acoustic reverberation technique offers a practical procedure for measuring the overall reflection coeffi- cient for the entire reservoir. Dam displacement and acceleration responses and hydrodynamic pressures due to acceleration signals recorded at the base of the dam wer...

In turbomachinery, the perfect detuning of turbine blades in order to avoid high cycle fatigue damage due to resonant vibration is often unfeasible due to the high modal density of bladed disks. To obtain reliable predictions of resonant stress levels of turbine blades, accurate modeling of friction damping is mandatory. Blade root is one of the most common sources of friction damping in turbine blades; energy is dissipated by friction due to microslip between the blade and the disk contact surfaces held in contact by the ...

In this paper we summarize the hardware and software issues of impedance-based structural health monitoring based on piezoelectric materials. The basic concept of the method is to use high-frequency structural excitations to monitor the local area of a structure for changes in structural impedance that would indicate imminent damage. A brief overview of research work on experimental and theoretical studies on various structures is considered and several research papers on these topics are cited. This paper concludes with a discussion of future research areas and path forward.

Music plays an enormous role in today's computer games; it serves to elicit emotion, generate interest and convey important information. Traditional gaming music is fixed at the event level, where tracks loop until a state change is triggered. This behaviour however does not reflect musically the in-game state between these events. We propose a dynamic music environment, where music tracks adjust in real-time to the emotion of the in game state. We are looking to improve the affective response to symbolic music through the modification of structural and performative characteristics through the application of rule-based techniques.

In the analysis and design of framed structures, the traditional methods are based on the simplified assumption that the joints are completely either pinned or rigid. However, the experimental investigations show that the frame connections present an intermediate behaviour between these two extreme cases. The present work is concerned with the dynamic elastic analysis of semi-rigid plane frames subjected to

An unusually large number of minarets, which are slender tower structures, collapsed during the 1999 Kocaeli and Duzce, Turkey earthquakes with resulting damage to surrounding buildings and loss of life. The potential effects of the subsequently observed poor reinforcement detailing on the dynamic response is discussed. The probable cause of the extensive damage to reinforced concrete minarets is investigated by studying the observed failure modes and their seismic performance, and through the dynamic analysis of a representative minaret. The effects of spiral stairs, door openings, and balconies on the dynamic behavior are examined. The maximum dynamic internal force demands were compared with the calculated capacities. The locations of the maximum axial, shear, and flexural demands predicted from the finite element analysis of the minaret model were consistent with the earthquake damage observed at those critical locations.

Steady state and dynamic responses of two tree fern species of contrasting origins, Dicksonia antarctica (of Gondwanan origin) and Cyathea australis (Pan-tropical), were studied over two consecutive years under field conditions in a wet sclerophyll forest of south-east Australia. Irrespective of their different origins, there were no significant differences in photosynthetic performance between the two species. Growth irradiance and leaf temperature, but not plant water status, was significantly related to photosynthetic and morphological traits. At a common leaf temperature, maximum light-use efficiency of photosystem II (F v /F m ) was significantly lower in winter than in summer, suggesting some limitation to PSII efficiency potentially associated with cold winter mornings. Both species displayed seasonal acclimation in a number of measured photosynthetic parameters and frond traits (i.e. F v /F m , A sat , g s , N A , total chlorophyll, SLA). Acclimation of stomatal density to spatial variation in growth irradiance seemed limited in both species, although stomatal pattern differed between species. Because there were no significant differences between the two species in photosynthetic parameters, both species can be described by common carbon gain and water use models at the leaf scale.

This study combines existing hydraulic principles with recently developed methods for probing leaf hydraulic function to determine whether xylem physiology can explain the dynamic response of gas exchange both during drought and in the recovery phase after rewatering. Four conifer species from wet and dry forests were exposed to a range of water stresses by withholding water and then rewatering to observe the recovery process. During both phases midday transpiration and leaf water potential (C leaf) were monitored. Stomatal responses to C leaf were established for each species and these relationships used to evaluate whether the recovery of gas exchange after drought was limited by postembolism hydraulic repair in leaves. Furthermore, the timing of gas-exchange recovery was used to determine the maximum survivable water stress for each species and this index compared with data for both leaf and stem vulnerability to water-stress-induced dysfunction measured for each species. Recovery of gas exchange after water stress took between 1 and .100 d and during this period all species showed strong 1:1 conformity to a combined hydraulic-stomatal limitation model (r 2 = 0.70 across all plants). Gas-exchange recovery time showed two distinct phases, a rapid overnight recovery in plants stressed to ,50% loss of leaf hydraulic conductance (K leaf) and a highly C leaf-dependent phase in plants stressed to .50% loss of K leaf. Maximum recoverable water stress (C min) corresponded to a 95% loss of K leaf. Thus, we conclude that xylem hydraulics represents a direct limit to the drought tolerance of these conifer species.

This paper describes an experimental study of dam-water-foundation interaction conducted at Longyangxia Dam in China. In the primary tests, the dam and its retained water were excited by detonating large explosive charges in shallow water upstream from the dam. The dam and water responses to the explosives were recorded by accelerometers, pressure sensors, and three-component seismographs. In secondary tests, the average reflection coefficient of the reservoir boundaries was measured using a newly developed procedure based on the acoustic reverberation concept. The results obtained indicate that explosive detonations appear to be the best means for exciting the dam-water-foundation system, and that an acoustic reverberation technique offers a practical procedure for measuring the overall reflection coefficient for the entire reservoir. Dam displacement and acceleration responses due to acceleration signals recorded at the base of the dam were computed using current analytical procedures. Generally good agreement between the measured and computed responses were obtained but the prediction could be improved if non-uniform input motion could be defined and used.

Two test methods, one worked out in a Nordtest-project, and the other available as Japanese Industrial Standard, both developed to characterise building materials with respect to moisture buffering performance, are analysed in detail by a numerical study on four different materials. Both test methods are based on a similar kind of dynamic loading, but the specifications of each test protocol vary. Therefore, the sensitivity of the test protocols is investigated by varying different protocol parameters. Subsequently, the practical applicability of the obtained values is investigated by confronting the values obtained for the four materials with the dynamic response of a small room with each of the materials used in turns as finishing material. Finally, the results determined according to the dynamic test protocol are compared with values calculated from steady state material data.

A novel methodology for the diagnosis of an operating proton exchange membrane fuel cell (PEMFC) is proposed in this manuscript. The cell impedance can be represented as the sum of two terms: the membrane resistance and a second-order transfer function. An experimental procedure and a method to estimate the parameters of this impedance model from the experimental data, by applying parameter identification techniques, are proposed. The experimental procedure consists in reading the dynamic response of the cell voltage and current after the occurrence of small changes in the load value. This experimental procedure, intended for application on operating cells, does not significantly interfere with the cell operation. It has been designed supposing that the frequency range of the relevant cell phenomena is 1 Hz to 5 kHz. The required experimental equipment is inexpensive and easily portable. Analytical relationships have been derived in order to calculate the following cell electrochemical parameters from the model parameters: the diffusion resistance, the charge transfer resistance, the diffusion-related time constant, the membrane resistance and the double layer capacitance.

This paper presents a dynamic simulator of water-in-tube boilers with natural recirculation, the kind of equipment widely used in industries for steam generation either as a source of power or for providing heating capabilities in process plants. The development is based on a combination of two non-linear models, one for the evaporation in the vertical tubes and the other for the phase separation in the steam drum. An application is made to the boiler of a 30 MW thermoelectric power plant and the results are discussed. The dynamic responses of all variables show the consistency of the model representation with the expected behavior, including the effects of a PI level control adjusted using classic Ziegler -Nichols tuning rules.

The dynamic response of a Bimorph 1 cantilever (10 mm  1 mm  0:5 mm) is investigated experimentally in air and in Fluorinert TM (3M TM) liquids with varying viscosity but nearly the same density. The gap height d between the cantilever and a solid surface is varied from millimeter to micrometer range and the response of the cantilever is interpreted in terms of added mass m a and viscous damping coef®cient c v. Key dimensionless parameters based on the Navier±Stokes (N±S) equations include the kinetic Reynolds number R k ob 2 =4Z (o is the circular frequency and Z the kinematic viscosity) and the dimensionless gap height d/b, where b is the cantilever width. The added mass increases (and resonance frequency decreases) with increasing¯uid density and decreasing d/b, where the dimensionless gap height d/b has a stronger effect. The added mass coef®cient is independent of R k for R k > 270 and d=b > 0:01. The N±S equations can be linearized when d=b > 0:1. In liquids, the viscous damping coef®cient increases (and the Q-factor decreases) with increasing dynamic viscosity (decreasing R k) and decreasing d/b. In general, the viscous terms in the N±S equations affect the viscous damping coef®cient at all gaps. The implications of the results on sensor design are brie¯y discussed.

The Integrated Northern Tampa Bay (INTB) model application was developed using the Integrated Hydrologic Model (IHM) simulation engine to improve hydrologic assessment capabilities in a 10,000 square kilometer region of west -central Florida. IHM uses the EPA HSPF model to simulate surface-water processes and the US Geological Survey model MODFLOW to simulate ground-water processes. With near simultaneous integration of HSPF

Board level solder joint reliability performance during drop test is a critical concern to semiconductor and electronic product manufacturers. A new JEDEC standard for board level drop test of handheld electronic products was just released to specify the drop test procedure and conditions. However, there is no detailed information stated on dynamic responses of printed circuit board (PCB) and solder joints which are closely related to stress and strain of solder joints that affect the solder joint reliability, nor there is any simulation technique which provides good correlation with experimental measurements of dynamic responses of PCB and the resulting solder joint reliability during the entire drop impact process. In this paper, comprehensive dynamic responses of PCB and solder joints, e.g., acceleration, strains, and resistance, are measured and analyzed with a multichannel real-time electrical monitoring system, and simulated with a novel input acceleration (Input-G) method. The solder joint failure process, i.e., crack initiation, propagation, and opening, is well understood from the behavior of dynamic resistance. It is found experimentally and numerically that the mechanical shock causes multiple PCB bending or vibration which induces the solder joint fatigue failure. It is proven that the peeling stress of the critical solder joint is the dominant failure indicator by simulation, which correlates well with the observations and assumptions by experiment. Coincidence of cyclic change among dynamic resistance of solder joints, dynamic strains of PCB, and the peeling stress of the critical solder joints indicates that the solder joint crack opens and closes when the PCB bends down and up, and the critical solder joint failure is induced by cyclic peeling stress. The failure mode and location of critical solder balls predicted by modeling correlate well with experimental observation by cross section and dye penetration tests.

The estimation of response parameters plays an important role in the design of offshore structure. The periodic inspection and monitoring of offshore platforms for certification needs the study of the responses of structures owing to wave and wind forces. The complex dynamic behavior of the platform to the environmental loads makes it difficult to calculate exactly the dynamic responses. The present need of the industry is to have a time saving and accurate calculation methods, which can be in good agreement with the actual response parameters.

Induction motor has been the workhouse in various industries, household purpose like washing machine, pumps etc. due to its low cost, low maintenance and well equipped construction features. This paper presents a smart speed control system for three phase induction motor using Neuro-fuzzy controller. Neuro-fuzzy controller plays a major role in improving the performance of the induction motor based on the settling time transient response dynamic response due to load variation and environmental conditions and set speed variation. The simulation results for the fuzzy logic controller and Neuro-fuzzy controller are compared. The results show the superiority of the Neuro-fuzzy controller in improving the performance of the three phase induction motor. The simulation design is tested using various toolboxes in MATLAB.

The Integrated Northern Tampa Bay (INTB) model application was developed using the Integrated Hydrologic Model (IHM) simulation engine to improve hydrologic assessment capabilities in a 10,000 square kilometer region of west-central Florida. IHM uses the EPA HSPF model to simulate surface-water processes and the US Geological Survey model MODFLOW to simulate ground-water processes. With near simultaneous integration of HSPF with M ODFLOW, IHM provides the ability to simulate hydrologic transitions that occur between deep (>2 meters) and near-surface (0-2 meters) water-table conditions which influence surface and ground water processes. Compared to prior applications, the INTB model shows improvements in the dynamic response of hydrologic processes while using input data which is better constrained to physical measurements. Parameter estimation and manual calibration was used by employing quantitative metrics for streamflow, spring discharge, ground-water heads, depth to water table, temporal change in head and flow, and target ET. Qualitative metrics were developed for dry/flooded cells and various wet/dry stage metrics for water bodies. Quantitative metrics were applied using statistics for the mean, above and below the median, and within the high and low quartiles. Recent improvements in the dynamic response of the INTB model are the outcome of refinements to the simulation engine, enforcing hydrologic similarity principles within discretization units, constraining the model with average annual ET targets, and applying the calibration metric of depth to water table.

A semi-analytical analysis for the transient elastodynamic response of an arbitrarily thick simply supported beam due to the action of an arbitrary moving transverse load is presented, based on the linear theory of elasticity. The solution of the problem is derived by means of the powerful state space technique in conjunction with the Laplace transformation with respect to the time coordinate. The inversion of Laplace transform has been carried out numerically using Durbin’s approach based on Fourier series expansion. Special convergence enhancement techniques are invoked to completely eradicate spurious oscillations and obtain uniformly convergent solutions. Detailed numerical results for the transient vibratory responses of concrete beams of selected thickness parameters are obtained and compared for three types of harmonic moving concentrated loads: accelerated, decelerated and uniform. The effects of the load velocity, pulsation frequency and beam aspect ratio on the dynamic response are examined. Also, comparisons are made against solutions based on Euler–Bernoulli and Timoshenko beam models. Limiting cases are considered, and the validity of the model is established by comparison with the solutions available in the existing literature as well as with the aid of a commercial finite element package.

Ahstr~tet--Periods of elevated temperatures in northern Monterey Bay suggest that this is a region of increased residence time during periods of active upwelling. Nearshore increases in near-surface temperature often coincide with offshore decreases in temperature as cold, upwelled water is advected into the center of the bay--the juxtaposition of warm and cold water enhancing the thermal signature of a feature described as an 'upwelling shadow'. We present a variety of data collected from 1988 to 1993 invoking a shallow, stratified, cyclonic circulation in northern Monterey Bay to explain the upwelling shadow as a dynamic response to upwelling north of the bay. Residence times associated with this warm recirculation are of the order of 8 days which is comparable to semi-enclosed embayments whereas Monterey Bay is an open embayment. We estimate a continuous replacement of upwelling shadow water with offshore water at a rate of 0.083 day-1 and we suggest that a circulation velocity of 0.1 m-s-1, is needed to produce the thermal signature of the feature given published values of surface heat flux in the central California coastal region. The thermal signature of this upwelling shadow persists through much of the upwelling season, surviving brief relaxations in upwelling but breaking down during prolonged relaxations of the order of a week or longer. The stratification and coherent recirculation of this feature is likely to be very important for such biological processes as productivity and the dispersal and recruitment of larvae.

In this study, mathematical modelling and dynamic response of a flexible robot manipulator with rotating-prismatic joint are investigated. The tip end of the flexible robot manipulator traces a multi-straight-line path under the action of an external driving torque and an axial force. Considered robot manipulator consists of a rotating prismatic joint and a sliding flexible arm with a tip mass. Flexible arm is assumed to be an Euler-Bernoulli beam carrying an end-mass. Equations of motion of the flexible manipulator are obtained by using Lagrange's equation of motion. Effect of rotary inertia, axial shortening and gravitation is considered in the analysis. Equations of motion are solved by using fourth order Runge-Kutta method. Numerical simulations obtained by using a developed computer program are presented and physical trend of the results are discussed.

In this paper the analysis and experimental study of three kinds of inverters are presented. Beginning with the traditional full bridge buck inverter; followed by two different inverter approaches, the boost and buck boost ones. This last two converters have the property of produce an output voltage higher or lower than the input voltage additionally to its inversion capability, which is a desired characteristic to some applications.

Planetary gears are widely used in aeronautic and industrial applications that require compactness and high torque-to-weight ratios. Despite these advantages, the severe conditions under which such gears are typically used may lead to failure. Tooth pitting and cracking are frequently encountered failure modes. The defects are modeled and discussed for a planetary gear set. The influence of tooth defects on gear mesh stiffness is scrutinized. Healthy planetary gear dynamic response and the response of planetary gears containing tooth defects are compared in both the time and frequency domains and in the joint timefrequency domains by use of the Wigner-Ville distribution.

The issue of gravity induced instability during response to severe seismic excitation is examined. It is contended that while static instability is fully determined by the existence of at least one negative eigenvalue in the second-order tangent stiffness, this condition is necessary, but not sufficient for instability during dynamic response. It is noted that the likelihood of collapse is strongly dependent on the shape of the mechanism that controls during the critical displacement cycle and that this shape can be reasonably identified using a pushover analysis with an appropriately selected lateral load distribution. A characterization of the instability limit state based on reduction of a multistorey building to an equivalent SDOF system is presented.

A comprehensive experimental analysis is conducted for measuring dynamic response of jerk optimized, stress optimized and size optimized cams, with advanced techniques of data acquisition and data processing. A precision manufacturing process is employed for preparing cam surface. Results show close matching of experimental outputs with theoretical predictions of displacement and values of follower preset. A method is suggested for specifying the causes behind deviations of predicted cam displacements from actual displacements.

In this paper, a dynamic model for Toyota Prius 2004 hybrid electric vehicle (HEV) is presented. The model is based on MATLAB Simulink HEV model which is modified in such a way that dynamic response of model can be verified by experimental results given in DOE reports for Toyota Prius 2004. The newly developed model can help the designers to

Study the dynamic properties of Turbo-Generator foundation with and without passive supplemental damping are considered in this paper using finite element method. The high vibrations of machines especially Turbo-Generators machines lead to use massive masses of foundations to absorb the big amount of dynamic loads generated by machines. The work in this paper investigates the effect of using passive supplemental damping devices such as lead rubber bearings to accommodate these big amount of dynamic loads, also investigates how it could lead to change the dynamic responses of Turbo-Generator foundations to be in the safe frequency range with less masses and better dynamic performance. The analysis of the system with and without supplemental damping devices is performed which shows the significant effect of using damping devices. The results show that damping devices could lead to decrease masses of top deck of the machine foundation by 20% with acceptable dynamic responses compared with foundations without supplemental damping devices. A proof of the high significant of damping devices especially lead rubber bearings in decreasing the construction cost and changing the dynamic behavior of Turbo-generator machine foundation is presented by performing a detailed comparison study with and without damping devices.

The performance of doubly fed induction generator (DFIG) variable speed wind turbine under network fault is studied using simulator developed in MATLAB/SIMULINK. Simulation results show the transient behavior of the doubly fed induction generator when a sudden short circuit at the generator bus is introduced. After the clearance of the short-circuit fault the control schemes manage to restore the wind

This paper proposes a novel and simple direct power control of three-phase pulsewidth-modulated (PWM) rectifiers with constant switching frequency using space-vector modulation (DPC-SVM). The active and reactive powers are used as the pulse width modulated (PWM) control variables instead of the three-phase line currents being used. Moreover, line voltage sensors are replaced by a virtual flux estimator. The theoretical principle of this method is discussed. The steady-state and dynamic results of DPC-SVM that illustrate the operation and performance of the proposed system are presented. It is shown that DPC-SVM exhibits several features, such as a simple algorithm, good dynamic response, constant switching frequency, and particularly it provides sinusoidal line current when supply voltage is not ideal. Results have proven excellent performance and verify the validity of the proposed system.