scholarly journals Nonlinear Vibrations of Innovative One-Way Clutch in Vehicle Alternator

Inventions ◽  
2018 ◽  
Vol 3 (3) ◽  
pp. 53
Author(s):  
Xiaotian Xu ◽  
Gang Chen ◽  
Joshua Colley ◽  
Pengrui Li ◽  
Mohamad Qatu
Keyword(s):  
Nonlinear Vibrations ◽  
Primary Resonance ◽  
System Model ◽  
System A ◽  
Vehicle Engine ◽  
Clutch System ◽  
Big Picture ◽  
The One ◽  
Harmonic Resonance ◽  
Super Harmonic Resonance

One-way clutches have been proposed for vehicle alternators. The clutch can play an important role in reducing vibrations of the vehicle engine accessory system, but the severe vibrations of the clutch subsystem limit its stability and durability. This paper investigates the nonlinear vibrations of a one-way clutch between the accessory pulley and the alternator shaft. The one-way clutch is modelled as a discontinuous stiffness system, and the simplified model is analyzed using discontinuous transform to determine the periodic, primary resonance and the sub and super harmonic resonance solutions. The typical system model is numerically solved and the spectrum and phase plots are characterized. The results give a big picture of and insights into the nonlinear vibration features of one-way clutch system. A relevant US patent is pending.

Exploiting Super-Harmonic Resonances of a Bi-Stable Axially-Loaded Beam for Energy Harvesting Under Low-Frequency Excitations

2011 ◽  
Author(s):  
Ravindra Masana ◽  
Mohammed F. Daqaq
Keyword(s):  
Energy Harvesting ◽  
Low Frequency ◽  
Primary Resonance ◽  
Energy Harvesters ◽  
Piezoelectric Beam ◽  
Frequency Components ◽  
Voltage Frequency ◽  
Axially Loaded ◽  
Harmonic Resonance ◽  
Super Harmonic Resonance

A research paradox currently lies in the design of miniaturized vibratory energy harvesters capable of harnessing energy efficiently from low-frequency excitations. To address this problem, this effort investigates the prospect of utilizing super-harmonic resonances of a bi-stable system to harvest energy from excitation sources with low-frequency components. Towards that objective, the paper considers the electromechanical response of an axially-loaded clamped-clamped piezoelectric beam harvester with bi-stable potential characteristics. By numerically constructing the voltage-frequency bifurcation maps of the response near the super-harmonic resonance of order two, it is shown that, for certain base excitation levels, the harvester can exhibit responses that are favorable for energy harvesting. These include a unique branch of large-orbit periodic inter-well oscillations, coexisting branches of large-orbit solutions, and a bandwidth of frequencies where a unique chaotic attractor exists. In these regions, the harvester can produce power levels that are comparable to those obtained near the primary resonance.

Purification of a Specific Placental Plasminogen Activator Inhibitor by Monoclonal Antibody and Its Complex Formation with Plasminogen Activator

1985 ◽  
Vol 53 (01) ◽  
pp. 122-125 ◽  
Author(s):  
B Åstedt ◽  
Ingegerd Lecander ◽  
T Brodin ◽  
A Lundblad ◽  
Karin Löw
Keyword(s):  
Monoclonal Antibody ◽  
Complex Formation ◽  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Tissue Type ◽  
System A ◽  
The One ◽  
Fast Acting ◽  
Chain Form ◽  
Activator Inhibitor

SummaryA monoclonal antibody of IgG2a-type was obtained against a specific fast acting plasminogen activator inhibitor found in placenta. The placental inhibitor was purified by affinity chromatography using the monoclonal antibody and additionally in a FPLC-system. A strong complex formation was found between the inhibitor and urokinase and also with the two-chain form of plasminogen activator of the tissue-type. A weaker complex was found between the placental inhibitor and the one- chain form of the tissue-type activator.

Nonlinear Vibrations of Two-Span Composite Laminated Plates with Equal and Unequal Subspan Lengths

2017 ◽  
Vol 9 (6) ◽  
pp. 1485-1505
Author(s):  
Lingchang Meng ◽  
Fengming Li
Keyword(s):  
Multiple Scales ◽  
Equations Of Motion ◽  
Primary Resonance ◽  
Laminated Plates ◽  
Laminated Plate ◽  
Composite Laminated Plate ◽  
Vibration Localization ◽  
Composite Laminated Plates ◽  
Localization Phenomenon ◽  
Harmonic Resonance

AbstractThe nonlinear transverse vibrations of ordered and disordered two-dimensional (2D) two-span composite laminated plates are studied. Based on the von Karman's large deformation theory, the equations of motion of each-span composite laminated plate are formulated using Hamilton's principle, and the partial differential equations are discretized into nonlinear ordinary ones through the Galerkin's method. The primary resonance and 1/3 sub-harmonic resonance are investigated by using the method of multiple scales. The amplitude-frequency relations of the steady-state responses and their stability analyses in each kind of resonance are carried out. The effects of the disorder ratio and ply angle on the two different resonances are analyzed. From the numerical results, it can be concluded that disorder in the length of the two-span 2D composite laminated plate will cause the nonlinear vibration localization phenomenon, and with the increase of the disorder ratio, the vibration localization phenomenon will become more obvious. Moreover, the amplitude-frequency curves for both primary resonance and 1/3 sub-harmonic resonance obtained by the present analytical method are compared with those by the numerical integration, and satisfactory precision can be obtained for engineering applications and the results certify the correctness of the present approximately analytical solutions.

Harmonic Resonance Frequency Factor of Spur Gear System and Oscillation Reduction Approaches

2007 ◽  
Author(s):  
Jianping Wang ◽  
Pengfei Li ◽  
Ziying Wu ◽  
Minghong Zhang
Keyword(s):  
Parametric Excitation ◽  
Linear Time ◽  
Primary Resonance ◽  
Frequency Factor ◽  
Multiple Scale ◽  
Transmission Error ◽  
Spur Gear ◽  
High Order ◽  
Time Varying ◽  
Harmonic Resonance

In this study, a non-linear time-varying dynamic model of a spur gear pair system is used to investigate the dynamic behavior of the system by means of multiple scale approach. Both time-varying stiffness, transmission error and tooth backlash clearance of the system are taken into account in the model. The mesh stiffness fluctuation is developed as high order Fourier series and tooth backlash clearance is fitted by high order polynomial function. The frequency factors of the system are investigated and the frequency-response equations at the case of internal and external excitation, parametric excitation and combined excitation are obtained. The peak value of the amplitude of the primary resonance, super and sub harmonic resonance and combination harmonic under internal, external and parametric excitation are researched. The approaches of vibration reduction are investigated. Finally an example is investigated using the presented process and the results indicate the sensitivity and correctness of the presented analysis approaches.

Clinical Notes on Haemorrhages in General Paralysis

1886 ◽  
Vol 31 (136) ◽  
pp. 504-507
Author(s):  
Geo. H. Savage
Keyword(s):  
Nervous System ◽  
Nervous Disease ◽  
General Paralysis ◽  
Clinical Notes ◽  
System A ◽  
General Pathology ◽  
Mental Symptoms ◽  
The One ◽  
Nutritional Changes

In so-called nervous disorders it is common to find changes occur in other of the bodily systems than the nervous. The pathology of nervous disease should be looked upon as a general pathology, and it is certain that we cannot look to the one system alone for causes of all the nervous disorders without greatly misunderstanding the whole subject. The more exact we become in limiting the causes, the more liable are we to error. We are all prepared to consider general paralysis of the insane as essentially a disease of the nervous system, a disease in which nearly every part of the nervous system may suffer sooner or later. But beside the essentially nervous symptoms which occur in the disease, we are constantly struck by the regular series of nutritional changes which occur in general paralysis, and this is so much the case that we are quite prepared to recognise as general paralysis a disorder in which any mental symptoms have been present, but have after a brief period of acuteness been followed by a state of fatness and weak-mindedness which again has been followed by a period of wasting and further mental weakness. We have here nervous symptoms related very directly with nutritional changes.

Nonlinear Dynamics of One-Way Clutches in Belt-Pulley Systems

2003 ◽  
Author(s):  
Farong Zhu ◽  
Robert G. Parker
Keyword(s):  
Nonlinear Dynamics ◽  
Degrees Of Freedom ◽  
Piecewise Linear ◽  
Primary Resonance ◽  
Harmonic Balance Method ◽  
Excitation Amplitude ◽  
Relative Displacement ◽  
Second Primary ◽  
Arc Length ◽  
The One

One-way clutches are frequently used in the serpentine belt accessory drives of automobiles and heavy vehicles. The clutch plays a role similar to a vibration absorber in order to reduce belt/pulley vibration and noise and increase belt life. This paper analyzes a two-pulley system where the driven pulley has a one-way clutch between the pulley and accessory shaft that engages only for positive relative displacement between these components. The belt is modeled with linear springs that transmit torque from the driving pulley to the accessory pulley. The one-way clutch is modeled as a piecewise linear spring with discontinuous stiffness that separates the driven pulley into two degrees of freedom (DOF). The harmonic balance method (HBM) combined with arc-length continuation is employed to illustrate the nonlinear dynamic behavior of the one-way clutch. HBM with arc-length continuation yields the stable and unstable periodic solutions for given parameters. These solutions are examined across a range of excitation frequencies. The results are confirmed by numerical integration and the widely used bifurcation software AUTO. At the first primary resonance, most of the responses are aperiodic, including quasiperiodic and chaotic solutions. At the second primary resonance, the peak bends to the left with classical softening nonlinearity because clutch disengagement decouples the pulley and the accessory over portions of the response period. The dependence on system parameters such as clutch stiffness, excitation amplitude, and inertia ratio between the pulley and accessory is studied to characterize the nonlinear dynamics across a range of conditions.

Man, Institutions and Bioeconomics

2003 ◽  
Vol 14 (4) ◽  
pp. 339-355
Author(s):  
Javier Alfonso Gil
Keyword(s):  
Methodological Approach ◽  
Natural Habitat ◽  
Social Technology ◽  
Activity System ◽  
Material Technology ◽  
Political Market ◽  
System A ◽  
Biological Capacity ◽  
Growth Of Knowledge ◽  
The One

Because bioeconomics is born of the interaction between the biological activity system and its socio-economic activity system, a holistic methodological approach is essential to study the relations between them. However, it must search for increasing levels of reductionism within each discipline to delve into the ultimate nature of each one of the intervening forces, whether economic or biological. This paper explores the economic forces. Through the biological capacity to comprehend, man and by extension, society, accumulates knowledge, the fulcrum from which he is able to dominate over his natural habitat. From this ‘point d’appui’, man builds two basic tools to assist him in achieving the goal of bettering his social condition. On the one hand, he creates institutions that allow him to “live with others” and, on the other, he develops technology that helps him to “live better with others”. Institutions, also referred to as ‘social technology’, tend toward stability over time while technology or ‘material technology’, tends toward instability, which would suggest that, normally, the mechanics of change will originate in material technology and, from there, progress to social technology by way of the political market. The level of progress and development attained depends on the quantity and rate of growth of knowledge applied by a society. In the process, man and his collectivity are forced to adopt new views of their environment through new shared mental models. The concurrence of equipment and political market will ultimately become the prime mover of institutional and economic change as well as change in mentality. Both technologies must keep on an adaptive course of stable evolution since discrepancies arising between them can cause tension between the various social groups. Adequate management of technological shock is essential to avoid extreme situations of social conflict. Herein lie the most important political decisions that a government must confront over the long term.

scholarly journals Influence of radial clearance on nonlinear dynamics of a two-span three-support rotor system

2021 ◽  
Vol 233 ◽  
pp. 04012
Author(s):  
HE Xing ◽  
WU Yi-ming ◽  
LI Mo ◽  
ZENG Fan
Keyword(s):  
Periodic Motion ◽  
Rotor System ◽  
System Model ◽  
Radial Clearance ◽  
Structural Form ◽  
Single Cycle ◽  
Rolling Bearings ◽  
System A ◽  
Runge Kutta Method ◽  
Nonlinear Dynamic Characteristics

Aiming at the structural form of a certain rotor system, a double-span three-support rotor system model is established. It is supported by three rolling bearings and has a typical nonlinear characteristic. The fourth-order Runge-Kutta method is used to solve the differential equations and analyze the nonlinear dynamic characteristics of the rotor system when the radial clearance of the bearing changed. The research results: with the increase of the rear bearing radial clearance, the rotor system performs single cycle, periodic two and pseudo-periodic motion. With the three location bearing radial clearance increases, the rotor system performs single cycle, periodic two and periodic four motion. When the radial clearance is bigger, the rotor system performs two periodic motion. The influence law of radial clearance on double span three - braced rotor system is shown.

scholarly journals Gut microbiota and renin-angiotensin system: a complex interplay at local and systemic levels

2021 ◽  
Author(s):  
Kinga Jaworska ◽  
Mateusz Koper ◽  
Marcin Ufnal
Keyword(s):  
Gut Microbiota ◽  
Renin Angiotensin System ◽  
Gastrointestinal Diseases ◽  
Electrolyte Balance ◽  
Ample Evidence ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
System A ◽  
Potential Mediator ◽  
The One

Gut microbiota is a potent biological modulator of many physiological and pathological states. The renin-angiotensin system (RAS), including the local gastrointestinal RAS (GI RAS), emerges as a potential mediator of microbiota-related effects. The RAS is involved in cardiovascular system homeostasis, water-electrolyte balance, intestinal absorption, glycemic control, inflammation, carcinogenesis and aging-related processes. Ample evidence suggests a bidirectional interaction between the microbiome and RAS. On the one hand, gut bacteria and their metabolites may modulate GI and systemic RAS. On the other hand, changes in the intestinal habitat caused by alterations in RAS may shape microbiota metabolic activity and composition. Notably, the pharmacodynamic effects of the RAS-targeted therapies may be in part mediated by the intestinal RAS and changes in the microbiome. This review summarizes studies on gut microbiota and RAS physiology. Expanding the research on this topic may lay a foundation for new therapeutic paradigms in gastrointestinal diseases and multiple systemic disorders.

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