Oscillation

The limits of current micro-scale technology is approaching rapidly. As the technology is going toward nano-scale devices, physical phenomena involved are fundamentally different from micro-scale ones. Principles in classical physics are no longer powerful enough to explicate the phenomena involved in nano-scale devices. At this stage, quantum mechanic sheds some light on those topics which cannot be described by classical physics. The primary focus of this research work is the development of an analysis technique for understanding the behavior of strongly perturbed harmonic oscillators.

165p runthenight07 01-03-2023 6 3   Download

The objective of this research was to determine the role of neural feedback and muscle mechanics in the generation of physiological tremor oscillation. This research developed a neuromuscular model to simulate the individual and resulting oscillatory mechanisms of tremor. The oscillations found in EMG signal were also analysed empirically from EMG data from 54 subjects using Hilbert Transform and rectification to obtain the envelope of the signal. The time between rhythmical waveform patterns in the EMG signal, TC was found to be 78ms.

117p runthenight07 01-03-2023 6 3   Download

The current research is undertaken by performing Computational Fluid Dynamics (CFD) simulations for a 2D aerofoil fitted with a shock control bump at a transonic flow condition. Reynolds-Averaged Navier-Stokes equation coupled with turbulence models is adopted to solve the flowfield. The bump has a conventional geometric feature which consists of a ramp, a crest and a tail, and it has eight variants for which the designed parameters are reasonably specified according to the compressible aerodynamics theory.

84p runthenight04 02-02-2023 7 3   Download

Bài giảng Kỹ thuật nâng & vận chuyển - Chương 13: Máy vận chuyển liên tục không có bộ phận kéo (tractionless - type conveyors). Những nội dung chính trong chương này gồm có: Thiết bị trọng trường (gravity-type conveyor), băng lăn (gravity roller conveyors), máng lắc có áp lực thay đổi của vật lên máng (oscillating conveyor with variable pressure on deck), máng lắc có áp lực không đổi của vật lên máng (oscillating conveyor with constant pressure on deck).

12p lovebychance05 16-06-2021 19 3   Download

The main objective of the thesis is to provide general methods to control oscillation based on measurement of energy flow, namely: Find the optimal solution for passive control systems based on energy flows; propose the semi-active control algorithms to control the energy flow.

27p capheviahe27 23-02-2021 20 3   Download

The aims of this study are to develop and apply the method of using frequency response functions to diagnose cracks in elastic bar and beams structure. The contents of the study includes: building models of cracked elastic bar and 3 beams structure; studying the changes of oscillation parameters, mainly frequency response functions due to cracks.

27p larachdumlanat129 20-01-2021 23 6   Download

This paper presents a dynamic model of a tilting child travel seat. The child seat is presented as a physical pendulum. Thereby the seat in concert with the child can rotate around a cylindrical joint located above its mass center.

6p lucastanguyen 01-06-2020 15 3   Download

We study axial core oscillations due to xenon poisoning in thermal neutron nuclear reactors with simple 1D models: a linear one-group model, a linear two-group model, and a non-linear model taking the Doppler effect into account.

13p christabelhuynh 29-05-2020 7 1   Download

This article discusses possibilities of application of widely applied and promoted abroad methods of active dampening of vibration and pressure oscillations (antinoise technology) in order to reduce vibration transfer via vibro-insulating couplings (compensators) of fluid pipelines.

8p tohitohi 19-05-2020 15 0   Download

The dissertation aims to study to reduce torsional vibration for the shaft The machine is equipped with DVA (dynamic vibration absorber) oscillator, mass disk type - spring - viscous. To know more details of the content please refer to the thesis summary.

32p xacxuoc4321 11-07-2019 27 3   Download

The objective of the thesis: Study the effect of cracks on the dynamic characteristics of the structure, study the applicability of the time-frequency signal processing method in detecting cracks. Application and development the processing time-frequency oscillation signals methods for cracks detection.

37p xacxuoc4321 09-07-2019 47 6   Download

We previously reported that GTS1 is involved in regulating ultradian oscillations of the glycolytic pathway induced by cyanide in cell suspensions as well as oscillations of energy metabolism in aerobic continuous cultures. Here, we screened a yeast cDNA library for proteins that bind to Gts1p using the yeast two-hybrid system and cloned multiple TDH cDNAs encoding the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH).

10p research12 01-06-2013 40 3   Download

Fluorescence ratio imaging indicates that immobilized, aspirin-treated platelets, loaded with Fura-2, respond to inositol 1,4,5-trisphosphate- (InsP3)-generating agonists such as thrombin by high-frequency, irregular rises in cytosolic [Ca 2+ ] i with spikes that vary in peak level and peak-to-peak interval. This differs from the regular [Ca 2+ ] i oscillations observed inother, larger cells.

10p research12 29-04-2013 42 3   Download

This review provides a comparative overview of recent developments in the modelling of cellular calcium oscilla-tions. A large variety of mathematical models have been developed for this wide-spread phenomenon in intra- and intercellular signalling. From these, a general model is extracted that involves six types of concentration variables: inositol 1,4,5-trisphosphate (IP3), cytoplasmic, endoplasmic reticulum and mitochondrial calcium, the occupied binding sites of calcium buffers, and the fraction of active IP3 receptor calciumrelease channels....

23p research12 29-04-2013 27 3   Download

A cascade of events (signal-transduction), mainly seen in rat cardiac myocytes and renal cells, is thought to occur after ouabain interaction with a minor fraction of Na + /K + -ATPase. Ahigher intracellularNa + concentration followed sodium pump inhibition by ouabain with a subsequent gradual increase or oscillations in intracellular Ca 2+ con-centration. Whether this increase in intracellular Ca 2+ concentration is part of the cascade, a result of the cascadeor a totally independent phenomenon are conflicting interpre-tations that are discussed. ...

4p fptmusic 16-04-2013 33 3   Download

This work concerns the cause of glycolytic oscillations in yeast. We analyse experimental data as well as models in two distinct cases: the relaxation-like oscillations seen in yeast extracts, and the sinusoidal Hopf oscillations seen in intact yeast cells. In the case of yeast extracts, we use flux-change plots and model analyses to establish that the oscillations are driven by on⁄off switching of phosphofructokinase.

13p awards 06-04-2013 37 5   Download

We report that autonomous oscillations, which usually happen in aerobic glucose-limited continuous cultures of yeast at low dilution rate, were also observed in trehalose discontinuous cultures ofSaccharomyces cerevisiae. This unexpected oscillatory behaviour was therefore examined using fast Fourier transformation of online gas measurements. This robust mathemat-ical analysis underlined the existence of two types of oscillation.

11p awards 06-04-2013 36 2   Download

In both industrial fermenters and in their natural habitats, microorganisms often experience an inhomogeneous and fluctuating environment. In this paper we mimicked one aspect of this nonideal behaviour by imposing a low and oscillating extracellular glucose concentration on nonoscillating suspensions of yeast cells. The extracellular dynamics changed the intracel-lular dynamics – which was monitored through NADH fluorescence – from steady to equally dynamic; the latter followed the extracellular dynamics at the frequency of glucose pulsing....

9p awards 06-04-2013 47 4   Download

In view of the increasing number of reported concentration oscillations in living cells, methods are needed that can identify the causes of these oscillations. These causes always derive from the influences that concentrations have on reaction rates. The influences reach over many molecular reaction steps and are defined by the detailed molecular topology of the network. So-called
autoinfluence paths, which quantify the influence of one molecular species upon itself through a particular path through the network, can have positive or negative values....

11p awards 05-04-2013 46 5   Download

Ouabain, a sodiumpump (Na + /K + -ATPase) inhibitor, has been shown to act as a hormone and is possibly involved in the pathogenesis of hypertension. The mechanismby which ouabain may act was investigated using primary cultures of human umbilical artery endothelial cells (HUAECs), which are known to express and release the vasoconstrictive hor-mone endothelin (ET-1). Fiveminutes after application, low concentrations of ouabain induced Ca 2+ oscillations and stimulated ET-1 release from endothelial cells into the medium.

9p dell39 03-04-2013 34 4   Download