Seismic Proofing Capability of the Accumulated Semiactive Hydraulic Damper as an Active Interaction Control Device with Predictive Control

The intensity of natural disasters has increased recently, causing buildings’ damages which need to be reinforced to prevent their destruction. To improve the seismic proofing capability of Accumulated Semiactive Hydraulic Damper, it is converted to an Active Interaction Control device and synchronous control and predictive control methods are proposed. The full-scale shaking table test is used to test and verify the seismic proofing capability of the proposed AIC with these control methods. This study examines the shock absorption of test structure under excitation by external forces, influences of prediction time, stiffness of the auxiliary structure, synchronous switching, and asynchronous switching on the control effects, and the influence of control locations of test structure on the control effects of the proposed AIC. Test results show that, for the proposed AIC with synchronous control and predictive control of 0.10~0.13 seconds, the displacement reduction ratios are greater than 71%, the average acceleration reduction ratios are, respectively, 36.2% and 36.9%, at the 1st and 2nd floors, and the average base shear reduction ratio is 29.6%. The proposed AIC with suitable stiffeners for the auxiliary structure at each floor with synchronous control and predictive control provide high reliability and practicability for seismic proofing of buildings

Developing Dynamic Digital Image Techniques with Continuous Parameters to Detect Structural Damage

Several earthquakes with strong magnitude occurred globally at various locations, especially the unforgettable tsunami disaster caused by the earthquake in Indonesia and Japan. If the characteristics of structures can be well understood to implement new technology, the damages caused by most natural disasters can be significantly alleviated. In this research, dynamic digital image correlation method for using continuous parameter is applied for developing a low-cost digital image correlation coefficient method with advanced digital cameras and high-speed computers. The experimental study using cantilever test object with defect control confirms that the vibration mode calculated using this proposed method can highly express the defect locations. This proposed method combined with the sensitivity of Inter-Story Drift Mode Shape, IDMS, can also reveal the damage degree of damage structure. These test and analysis results indicate that this proposed method is high enough for applying to achieve the object of real-time online monitoring of structure

Energy dissipation behaviours and seismic reduction performance of a proposed velocity and displacement dependent hydraulic damper (VDHD)

A new oil‐pressure Velocity and Displacement Dependent Hydraulic Damper (VDHD) is proposed by adding an additional Relief Valve parallel to the Throttle Valve with a different aperture size. This objective is to obtain an adaptive control by changing the damping coefficient of the VDHD for better control of structural movement during earthquake. In order to simulate its actual energy elimination, a mathematical analysis model is developed based on the Maxwell Model, which is modified by adding a serial friction model and a small damper parallel to the friction model in this study. The mathematical simulated results are compared with the actual energy‐dissipating behaviours of this proposed damper. The comparison shows that this proposed mathematical modelling could accurately simulate the relation of force and displacement as well as the relation of force and velocity during the process of energy dissipation. In addition, results of both the laboratory shaking table test and simulation analyses are used to test and verify the seismic reduction performance of this proposed damper. The experimental and simulation results show that in spite of the magnitude of the earthquake, the proposed VDHD device has a superior effect on the control of structural displacement by achieving effective acceleration reduction. Santrauka Siūlomas naujas hidraulinis i greiti ir poslinki reaguojantis slopintuvas (HGPS), sukurtas prie droselinio vožtuvo su kintama apertūra pridejus atbulini vožtuva. Buvo siekiama užtikrinti geresne adaptyvia konstrukcijos judejimo žemes drebejimo metu kontrole keičiant HGPS slopinimo koeficienta. Norint modeliuoti tikraji energijos pašalinima, buvo sukurtas matematinis modelis, pagristas Maksvelo modeliu. Šis modelis buvo pakeistas prie trinties modelio pridejus nuosekluji trinties modeli ir nedideli slopintuva. Matematinio modeliavimo rezultatai lyginami su tikraja siūlomo gesintuvo energijos sklaida. Palyginimas rodo, kad matematinio modeliavimo rezultatai atitinka tikraja siūlomo gesintuvo elgsena. Lyginant skaičiavimo rezultatus su eksperimentiniais matyti, kad siūlomas matematinis modeliavimas leidžia tiksliai išreikšti jegos ir poslinkio bei jegos ir greičio ryšius, susidarančius energijos sklaidos metu. Laboratoriniai rezultatai, gauti naudojant vibracini stala, ir modeliavimo rezultatai taikomi tirti bei tikrinti siūlomo gesintuvo itaka mažinant seismines konstrukcijos charakteristikas. Eksperimentiniai ir modeliavimo rezultatai rodo, kad nepaisant žemes drebejimo laipsnio, siūlomas gesintuvas labai pagerina konstrukcijos poslinkiu kontrole efektyviai mažindamas judejimo pagreiti. First Published Online: 10 Feb 2011 Reikšminiai žodžiai: HGPS, Maksvelo modelis, diskretusis sprendinys, pasyvusis energijos skaidos prietaisas, vibracinio stalo bandymas, modeliuojamas konstrukcijos reakcijos mažinima

Developing a neutral equilibrium device as dynamic virtual piers for an emergency relief bridge

Every year, many natural disasters strike Taiwan, destroying bridges and disrupting traffic. To allow shipping of relief provisions and salvage, fabricated steel bridges are often used to construct emergency relief bridges. This kind of bridge must meet strength and functionality requirements. Strength depends on the materials used, while functionality depends on displacement control. These two requirements affect the section design of the bridge deck. In order to quickly build a light-weight bridge for emergency relief with displacement control, a neutral equilibrium mechanism is proposed and developed to control the deflection of an emergency relief bridge. A neutral equilibrium mechanism is a system with an internal control mechanism that can actively change the internal structure. Structural transformation causes the size variation of the action force to respond to continuous changes in bridge deflection. This mechanism can expand the effective span of the bridge, maintain its strength and functionality, and increase the convenience of building and mobility. Experimental results reveal that a virtual pier at the center of a bridge with this proposed mechanism installed can control vertical deflection caused by vehicles carrying heavy loads. Test and analysis records also reveal that the vertical displacement at the center of a bridge with the neutral equilibrium mechanism installed is close to zero. The practicality of this neutral equilibrium mechanism has been verified by experiment

Experimental Validation of Numerical Model for Bi-Tilt-Isolator

Bi-Tilt Isolator (BTI) is composed of bi-tilt beveled substrate and slider. The advantages of BTI are that the maximum upload seismic force of structure can be easily controlled and displacement of isolation layer will be reduced. Sliding force, friction force, and impulse force are caused in the slanting process of BTI, nonlinear behavior. A nonlinear mathematical model is derived based on the sliding upwards, sliding downwards, and transition stages. Then, BTI element of nonlinear analysis program, GENDYN, is developed by the fourth-order Runge-Kutta method, the discretized ordinary differential equation for three movement stages of BTI. Then, test set-up of superstructure installed with BTI is tested and recorded the real displacement and acceleration responses under conditions of full lubrication, mild lubrication, and without lubrication between interface of bi-tilt beveled substrate and slider with three various initial displacements. The comparison of simulation results and test results shows the following: (1) root mean square error is below 1.35% for WD40 sprayed, 0.47% for WD40 whipped, and 0.54% for without lubrication, respectively; (2) the maximum root mean square error for simulating with cubic polynomial function of friction is much less than those of constant friction except conditions of full lubrication, which are not affected by kinetic friction force; (3) application of cubic polynomial function for simulating friction of BTI with three different lubricated conditions can perform very fine simulation results, compared with the test results. This proposed mathematical model and BTI element of GENDYN program, using cubic polynomial function of friction, perform fine simulation capability to assess nonlinear isolation effect of structure installed with BTI

Activation of β-Adrenoceptors by Dobutamine May Induce a Higher Expression of Peroxisome Proliferator-Activated Receptors δ (PPARδ) in Neonatal Rat Cardiomyocytes

Recent evidence showed the role of peroxisome proliferator-activated receptors (PPARs) in cardiac function. Cardiac contraction induced by various agents is critical in restoring the activity of peroxisome proliferator-activated receptors δ (PPARδ) in cardiac myopathy. Because dobutamine is an agent widely used to treat heart failure in emergency setting, this study is aimed to investigate the change of PPARδ in response to dobutamine. Neonatal rat cardiomyocytes were used to examine the effects of dobutamine on PPARδ expression levels and cardiac troponin I (cTnI) phosphorylation via Western blotting analysis. We show that treatment with dobutamine increased PPARδ expression and cTnI phosphorylation in a time- and dose-dependent manner in neonatal rat cardiomyocytes. These increases were blocked by the antagonist of β1-adrenoceptors. Also, the action of dobutamine was related to the increase of calcium ions and diminished by chelating intracellular calcium. Additionally, dobutamine-induced action was reduced by the inhibition of downstream messengers involved in this calcium-related pathway. Moreover, deletion of PPARδ using siRNA generated the reduction of cTnI phosphorylation in cardiomyocytes treated with dobutamine. Thus, we concluded that PPARδ is increased by dobutamine in cardiac cells

Neural Network Control-Based Drive Design of Servomotor and Its Application to Automatic Guided Vehicle

An automatic guided vehicle (AGV) is extensively used for productions in a flexible manufacture system with high efficiency and high flexibility. A servomotor-based AGV is designed and implemented in this paper. In order to steer the AGV to go along a predefined path with corner or arc, the conventional proportional-integral-derivative (PID) control is used in the system. However, it is difficult to tune PID gains at various conditions. As a result, the neural network (NN) control is considered to assist the PID control for gain tuning. The experimental results are first provided to verify the correctness of the neural network plus PID control for 400 W-motor control system. Secondly, the AGV includes two sets of the designed motor systems and CAN BUS transmission so that it can move along the straight line and curve paths shown in the taped videos