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(chemical engineering)
A petroleum-refinery process for separating light gases from petroleum or gasoline, thus leaving a stable (less volatile) liquid so that it can be handled or stored with less change in composition.
(control systems)
Feedback introduced into vacuum tube or transistor amplifier stages to reduce distortion by making the amplification substantially independent of electrode voltages and tube constants.
Treatment of a magnetic material to improve the stability of its magnetic properties.
Maintenance of a desired orientation independent of the roll and pitch of a ship or aircraft.


The process of temporarily protecting a historic building until restoration or rehabilitation can begin; it typically includes making the building weathertight, structurally stable, and secure against intrusion. The U.S. Department of the Interior’s standards state: “to reestablish a weather resistant enclosure and the structural stability of an unsafe or deteriorated property while maintaining the essential form as it exists at the present.”



the attainment and fixation of a constant state or the maintenance of such a state. Examples include the maintenance of the constancy of a process, as in frequency stabilization, and increasing the stability of a substance, as in the stabilization ofpolymers.



in automatic control and regulation, the maintenance of a specified value over time of one or several controlled quantities x(t) in such a way that the value remains unaffected by disturbing (destabilizing) effects f. The effects, which can be external or internal with regard to the stabilized object, tend to deflect the controlled quantity from the specified value x0 (t) = x0= const. It is possible to stabilize not only any measured controlled quantity, such as the effective value of voltage, but also any given function of this quantity, including even a function of several primary measured quantities.

The efficiency of stabilization is quantitatively expressed by the dimensionless stabilization coefficient σ This coefficient is equal to the quotient obtained by dividing a small relative change in the destabilizing effect Δf/f by the resulting relatively small change in the controlled quantity Δx/x. At the limit, these small changes are replaced by differentials:

Ideal stabilization is attained at σ → ∞.

Several destabilizing effects may be present, in which case stabilization coefficients characterizing the influence of each of the factors are calculated. If the destabilizing effects are regular and mutually independent, their combined influence on the parameter being stabilized is equal to the algebraic sum of these effects. If the destabilizing effects are irregular (random), their combined influence on the parameter is evaluated as the geometric sum of the individual effects.

In general calculations involving stabilization systems, the coefficient σ-1 is frequently used; ideal stabilization of the controlled parameter is attained at σ1 → = ∞. Often, in place of the coefficients σ and σ–1, the values of the relative (δ) or absolute (Δ) deviation of the stabilized quantity from a specified constant value are used in evaluating the operation of a stabilization system. A distinction is made between φ, φ-1, δ, and Δ for instantaneous values of the controlled quantity x(t) (short-term stability) and for average values of the quantity over a longer period, a period characteristic of the particular stabilization system or process (long-term, or integral, stability). In addition, for a slow change in x(t), a value known as drift ξ is used as a characteristic in evaluating the operational effectiveness of a stabilization system. The drift is usually calculated as the rate of departure of x(t) from a specified value x0 (during a specified characteristic time interval from O to t1,):

The two main groups of stabilizing devices, that is, stabilizers, are those with and those without feedback. Stabilizers without feedback can be parametric or can effect an automatic compensation of destabilizing effects. Stabilizers with feedback, referred to as automatic controllers, correct the deviations of the controlled quantity x(t) from the desired value x0 generated by a setting (master) device.

Parametric stabilizers utilize a nonlinear stabilizing element whose controlled output quantity in the operational range is practically independent of input values. Here, if the influence of all other destabilizing effects is small in comparison with the change in the generalized input, a nearly constant value of the controlled quantity will be obtained at the parametric stabilizer’s output. Parametric stabilizers are widely used for stabilizing electrical quantities, such as voltage.

In stabilizers with automatic compensation of a destabilizing effect, the controlling quantity is generated as a function of this sole or, at any rate, principal factor. In a number of cases, a nonlinear element is used for automatic compensation of the main destabilizing effect, just as in parametric stabilizers. If there are two or more substantial destabilizing factors in a given system, stabilization through automatic compensation of destabilizing effects becomes less effective and as such has practically no technical applications. In these cases, combined stabilizers with two control circuits are used. One circuit is actuated by the main disturbance (destabilizing effect) and thus has no feedback; the other is actuated by deviations and utilizes feedback. In this case, the provision of a circuit that compensates for destabilizing effects significantly increases the operational speed of the stabilizer; that is, it reduces time lags. The increase is achieved because control actuated by disturbances, which involves expenditure of time, is not required in arriving at the deviation of the controlled quantity from the desired value.

A stabilizer with feedback has a closed loop and compares the actual instantaneous value of the controlled quantity x(t) with the desired value x0. The error signal e(r) = x0x(t), transformed if necessary and amplified, serves as a basis for the controlling action. This action is directed, through the agency of the controller, toward decreasing ∊(t); the controlled output then again enters the comparator through the feedback loop and a new error signal is produced. This process continues until the threshold of sensitivity of any of the elements in the loop can no longer be reached.


Dusavitskii, Iu. Ia. Magnitnye stabilizatory postoiannogo napriazheniia. Moscow, 1970.
Lukes, J. H. Skhemy na poluprovodnikovykh diodakh. Moscow, 1972. (Translated from German.)
Teoriia avtomaticheskogo upravleniia, part 2. Edited by A. V. Netushil. Moscow, 1972.
Osnovy avtomaticheskogo upravleniia, 3rd ed. Edited by V. S. Pugachev. Moscow, 1974.
Zhuravlev, A. A., and K. B. Mazel’. Preobrazovateli postoiannogo napriazheniia na tranzistorakh, 3rd ed. Moscow, 1974.



The action of improving the stability of the sloped surface of a soil mass.
References in periodicals archive ?
Lower-molecular-weight nonionic dispersants, and/or high-HLB ethoxylated surfactants, provide dynamic stabilization characteristics optimal for milling benefits as well as compatibilization in letdown.
The incidence rate, severity, and time course of adverse events for dynamic stabilization systems compared with traditional systems.
The type, incidence rate and time course of subsequent surgical procedures for dynamic stabilization systerns compared with traditional stabilization systems.
Millennium Research Group's US Markets for Spinal Implants 2011 report includes procedure, unit, average selling price and revenue information for traditional thoracolumbar implants, traditional cervical implants, interbody devices and spinal nonfusion technologies (interspinous process decompression devices, pedicle screw-based dynamic stabilization devices, cervical artificial discs, lumbar artificial discs, facet arthroplasty devices, annulus repair devices and nuclear disc prostheses) in the United States.
Flex(+)[TM] Hybrid employs a unique technology enabling the combination of rigid and flexible parts in one low profile implant --the rigid section of the rod can be used to stabilize a vertebral segment requiring fusion, while the flexible section simultaneously provides dynamic stabilization.
TASK 11 - TLIF interbody intended for internal dynamic stabilization of the lumbar spine and sacral,
Introduction of motion preserving technologies like artificial disc replacement, interspinous spacers, and dynamic stabilization technologies in the recent past have provided surgeons with alternatives to fusion for some patients with these conditions.
TASK 9 - miedzywyrostkowa dynamic stabilization of the lumbar,
The Percutaneous Dynamic Stabilization system is the first and only percutaneous bilateral facet-augmentation system for treating degenerative disc disease and Lumbar Spinal Stenosis.
Keywords: Cervical fusion, Thoracolumbar fusion, Interbody fusion (including stand-alone interbody devices), Vertebroplasty, Kyphoplasty, Artificial discs, Interspinous distraction devices, Dynamic stabilization, Annular repair, Nucleus replacement, Facet arthroplasty and lumbar, cervical electrical stimulation devices.
TORONTO -- According to Millennium Research Group (MRG), the global authority on medical technology market intelligence, the market for pedicle screw-based dynamic stabilization systems, already under pressure from the lack of FDA approval for nonfusion indications and 522 postmarket data requirements, will undergo a more significant contraction through 2015 due to the failure of Applied Spine Technologies to move forward with its anticipated spinal nonfusion product, Stabilimax.

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