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	Adaptive feedforward servo system - Patent 4533991 (Site not responding. Last check: 2007-11-05)
		The feedforward signal for a given mode of operation is determined by the mean error during the previous operation in the mode and by the feedforward signal used during the previous operation in the same mode.
		The feedforward signal, being based on the mean error of the previous operation in a particular mode of acceleration or deceleration, is added to the correction in an attempt to reduce the mean error during the present mode of operation.
		The present feedforward signal (k), i.e., the feedforward signal to be used on the next operation in the given mode, is found by adding the adaptive signal previously calculated to the last feedforward signal (k-1), i.e., the feedforward signal used during the last operation in the given mode.
	www.freepatentsonline.com /4533991.html (3448 words)

	The Trevey - A Unit of Lasting Forests
		Feedforward predicts the future, compares it to objectives, and makes adjustments in the major elements of the present system so that the total system will be very responsive over time to the predicted future conditions.
		Feedforward is not the prediction itself (called "a prediction", a "forecast", or a "future") but the total process (a mini-system) of preparing now for the future.
		Feedforward is that subsystem that seeks to estimate or comprehend the future and then to revise the present system based on that perception.
	fwie.fw.vt.edu /rhgiles/Trevey/Feedforward.htm (1689 words)

	Feedforward for faster control response (Site not responding. Last check: 2007-11-05)
		Feedforward is based on the structure in control systems where one loop is nested inside another.
		The feedforward path is essentially a shortcut around the slower outer loop, allowing the command signal direct access to the faster inner loop.
		Feedforward is a practical way to speed up these systems without producing the problems caused by high loop gains.
	www.manufacturing.net /ctl/index.asp?layout=articlePrint&articleID=CA188255 (524 words)

	Buffering, feedback, feedforward: mechanisms of control
		Feedback and feedforward both require action on the part of the system, to suppress or compensate the effect of the fluctuation.
		Feedforward control will suppress the disturbance before it has had the chance to affect the system's essential variables.
		For example, feedforward control might be applied to the thermostatically controlled room by installing a temperature sensor outside of the room, which would warn the thermostat about a drop in the outside temperature, so that it could start heating before this would affect the inside temperature.
	pespmc1.vub.ac.be /MECHCONT.html (860 words)

	THE FEEDFORWARD MODEL
		Hubel and Wiesel (1962) first described orientation selectivity in the neurons of the cat visual cortex, they proposed an elegantly direct model that remains at the center of the debate.
		Their model represents the feedforward model in its simplest form, explaining orientation selectivity solely from the organization of the thalamic input to a simple cell in cortical layer 4.
		The essence of the feedforward model, then, is a linear summation stage, in which the input from the presynaptic geniculate neurons is summed on the membrane of the simple cell, followed by a non-linear rectification stage, in which the action potential threshold filters out the small synaptic inputs that are evoked by improperly oriented stimuli.
	keck.ucsf.edu /~ken/fm_final/node3.html (339 words)

	MachineDesign.com: Getting the most out of servocontrollers (Site not responding. Last check: 2007-11-05)
		Feedforward refers to the addition of open-loop information that is available to the profile generator such as desired velocity and desired acceleration.
		The tuning of feedforward systems starts with the velocity feedforward term, adjusting it to make servo lag as small as possible, and focuses on a portion of the profile where the velocity is flat.
		Feedforward will help when there are elements in your motion system that add a lag proportional to the feedforward term.
	www.machinedesign.com /ASP/viewSelectedArticle.asp?strArticleId=55300 (2229 words)

	Blogger: Email Post to a Friend (Site not responding. Last check: 2007-11-05)
		Feedforward is a phrase coined by Marshall Goldsmith and Jon Katzenbach (author of The Wisdom of Teams).
		Feedforward focuses on creating a future, as opposed to feedback, which is often focused on past behaviors.
		Good feedback really is feedforward - looking at what we can do better, focusing on future results, and encourging people to repeat things that are going well.
	www.blogger.com /email-post.g?blogID=6648003&postID=108247851697438844 (226 words)

	comp.ai.neural-nets FAQ, Part 1 of 7: Introduction
		To be somewhat more precise, feedforward networks with a single hidden layer and trained by least-squares are statistically consistent estimators of arbitrary square-integrable regression functions under certain practically-satisfiable assumptions regarding sampling, target noise, number of hidden units, size of weights, and form of hidden-unit activation function (White, 1990).
		Feedforward networks with a single hidden layer using threshold or sigmoid activation functions are universally consistent estimators of binary classifications (Faragó and Lugosi, 1993; Lugosi and Zeger 1995; Devroye, Györfi, and Lugosi, 1996) under similar assumptions.
		Feedforward nets are a subset of the class of nonlinear regression and discrimination models.
	www.uni-giessen.de /faq/archiv/ai-faq.neural-nets.part1-7/msg00000.html (12876 words)

	difference between two kind of feedforward in cascade feedback control (Site not responding. Last check: 2007-11-05)
		- velocity feedforward is applied to the velocity loop and acceleration feedforward is applied to the current loop, respectively.
		I know intuitively that the velocity feedforward is applied to the velocity command and the acceleration feedforward is applied to the current command.
		Of course that theoretically correctly is "velocity feedforward is applied to the velocity loop and acceleration feedforward is applied to the current loop, respectively".
	www.control.com /1026200646/index_html (764 words)

	Heating Highlights: Feedforward: Fast Compensation for Disturbances (Site not responding. Last check: 2007-11-05)
		In this example of a process with feedforward control, the wrapped wire temperature is sensed by an infrared thermometer and passed to the controller, whose analog DC output drives the induction heater that brings the wire up to the desired temperature.
		Feedforward is a solution worth bearing in mind.
		As shown in figure 2, use a controller with a time-proportioning output having a percentage on time that varies not only with the controller's PID output but also as 1/V2 (sometimes called power feedback though it is an example of feedforward).
	www.process-heating.com /CDA/ArticleInformation/Heating_Highlights_Item/0,3276,71803,00.html (782 words)

	Feedforward, a great leadership tool
		Feedforward, on the other hand, is almost always seen as positive because it focuses on solutions -- not problems.
		Feedforward can be a useful tool to apply with managers, peers and team members.
		By using feedforward leaders can dramatically improve the quality of communication in their organisations, ensuring that the right message is conveyed, and that those who receive it are receptive to its content.
	in.rediff.com /money/2005/aug/23guest.htm (1583 words)

	MICRO: Advanced Process
		In subtracting the previously deposited thin-film measurements from the total step height to estimate the amount of silicon etched, the process model assumed, first, that the feedforward metrology measurements of prior film layers were always available, and, second, that both the process and metrology noise in the feedforward measurements were centered around zero.
		The measurements were subject to a limited metrology sampling plan, and feedforward metrology was sometimes biased by either process or metrology noise from the film layers.
		Feedforward metrology disturbances can be observed by evaluating correlation coefficients between measured trench depth and feedforward films.
	www.micromagazine.com /archive/04/06/chong.html (2856 words)

	Feedforward MFA Controller
		Feedforward is a control scheme to take advantage of disturbance signals.
		If a process has a significant measurable disturbance, a feedforward controller can be used to reduce its effect before the feedback loop takes corrective action.
		In order to assure that the feedforward action rejects the disturbance, the rules for selecting the sign are (1) if processes Gp1 and Gp2 have the same sign, the FF's gain should be negative; and if processes Gp1 and Gp2 have different signs, the FF's gain should be positive.
	www.cyboman.com /technologies/feedforwardmfa.html (262 words)

	Feedforward Comb Filters
		The feedforward comb filter is normally implemented as shown in Fig.
		We see that the feedforward comb filter is a particular type of FIR filter.
		It is also a type of TDL in which the output is formed as a linear combination of the delay line's input and output.
	ccrma-www.stanford.edu /~jos/waveguide/Feedforward_Comb_Filters.html (251 words)

	Try Feedforward Instead of Feedback!
		In one role, they are asked provide feedforward —that is, to give someone else suggestions for the future and help as much as they can.
		Feedforward, on the other hand, is almost always seen as positive because it focuses on solutions.
		Feedforward is based on the assumption that people can make positive changes in the future.
	www.hodu.com /employee-motivation.3.shtml (1823 words)

	Feedforward MFA Controller
		Feedforward compensation can be as simple as a ratio between two signals, or involve complicated energy or material balance calculations.
		Since the feedback MFA adapts, the feedforward MFA can be designed in a simple form with parameters of a feedforward gain and time constant.
		The feedforward time constant can be an estimate of the time constant of Gp2.
	www.cybosoft.com /technologies/feedforwardmfa.html (262 words)

	Feedforward Neural Networks
		Feedforward neural networks (FF networks) are the most popular and most widely used models in many practical applications.
		The training process is described in Section 2.5.3, Training Feedforward and Radial Basis Function Networks.
		This is illustrated in Section 13.3.2, The Neuron Function in a Feedforward Network.
	documents.wolfram.com /applications/neuralnetworks/NeuralNetworkTheory/2.5.1.html (812 words)

	CiteULike: Diverse types of interneurons generate thalamus-evoked feedforward inhibition in the mouse barrel cortex. (Site not responding. Last check: 2007-11-05)
		This feedforward inhibition is generated by intracortical interneurons whose precise identity and properties were not known.
		To characterize interneurons generating feedforward inhibition, neurons in layers IV and V of mouse somatosensory ("barrel") cortex in vitro were tested in the cell-attached configuration for thalamocortically induced firing and in the whole-cell mode for synaptic responses.
		Morphological analysis revealed that some interneurons might generate feedforward inhibition within their own layer IV barrel, whereas others may convey inhibition to upper layers, within their own or in adjacent columns.
	www.citeulike.org /user/abes/article/134362 (376 words)

	Experimental support for the feedforward model with push-pull inhibition and same-phase excitation
		The feedforward model with push-pull inhibition and same-phase excitation is consistent with a number of observations obtained from intracellular recordings of simple cells and described above.
		Ferster et al., 1996), which show that the orientation tuning of visually-evoked responses does not change when cortical cells are silenced, and show additionally that the cortex amplifies responses to the LGN inputs 2- to 3-fold.
		Because it is a variant of the feedforward model and because it relies on the spatial organization of the geniculate input for establishing orientation selectivity, Troyer et al's model also exhibits a decrease in orientation tuning width with increasing stimulus spatial frequency (
	keck.ucsf.edu /~ken/fm_final/node17.html (269 words)

	ChE 162 Lab Manual - E2. Feedback-feedforward Control of Temperature in a Fixed-Bed Chemical Reactor
		The first scheme is a direct feedforward controller that increases the flowrate of gas when the inlet concentration increases; the second is a reverse feedforward controller that decreases the gas flowrate when inlet concentration increases.
		The direct feedforward controller reduces the residence time of the gas, and therefore may reduce the amount of combustion that takes places, hopefully balancing the effect of higher concentration.
		The reverse feedforward controller simply pumps less material through, and since the operating kinetics parameters of the reactor is such that basically all the gas is reacted, pumping less through should reduce the temperature.
	jwgibbs.cchem.berkeley.edu /che162/manual/E2.htm (922 words)

	Perception: ECVP 2003 abstracts (Site not responding. Last check: 2007-11-05)
		Intrinsic, feedforward, and feedback connections of single cortical columns of areas 17, 18, 19, or 21a in the cat were investigated.
		The number of feedforward projections from areas 17 and 18 to areas 19 and 21a was comparable to the number of their intrinsic connections.
		There was a difference in areas of origin of feedback projections to areas 17 and 18, and to areas 19 and 21a.
	www.perceptionweb.com /ecvp03/0794.html (221 words)

	Feedforward and backward computations
		The feedforward computations start with the parameters of the posterior approximation of the unknown variables of the model.
		the parameters of the posterior approximation is computed by the back-propagation algorithm, that is, the steps of the feedforward computations are reversed and the gradient of the cost function is propagated backwards to the parameters of the posterior approximation.
		Since the essential modification to the feedforward phase of NLFA algorithm is (8), this is also the essential modification in the backward computations.
	www.cis.hut.fi /harri/tr00/node5.html (358 words)

	[No title] (Site not responding. Last check: 2007-11-05)
		Feedforward control requires that out of control information, based on systematic process variations be available ahead of time.
		Feedforward control reduces the amount of feedback trim that is required.
		Predictions by the NN are fed to a feedforward controller.
	www.poms.org /POMSWebsite/Meeting1999/99papers/SD2F2.doc (1251 words)

	[No title]
		Host needs to make sure the value at the // first address is zero, since we sit there when the system is idle.
		As long as writes don't take place during the RF pulse, // there's no chance of using corrupted data for the feedforward.
		feedforward_we <= host_write_cycle & (ADDR_reg[13:10] == 4'b 0011); if (host_write_cycle & (ADDR_reg[13:10] == 4'b 0011)) feedforward_host_data <= PD[7:0]; // It probably doesn't matter, but give a consistent snapshot of the // status bits back to the host; this way none of them will change // in the middle of the read transaction.
	recycle.lbl.gov /~ldoolitt/ise/design_top.v (1265 words)

	Improved Design of Adaptive Feedforward Tracking Systems (Site not responding. Last check: 2007-11-05)
		The method is particularly significant for overparameterized adaptive feedforward systems, which are very important in practice; they are used to ensure high-performance "tuning" of key signals in a wide range of terrestrial and outer-space applications, including the ones listed above.
		Indeed, when an adaptive system is overparameterized, the PE condition is never satisfied, and therefore the older methods do not provide any clue as to the performance of the final adaptive design, much less provide guidelines on how to improve performance.
		The analysis reveals, further, that if the confluence matrix is positive definite, then the adaptive feedforward operator H from the error e to the estimate is input-output equivalent to an adaptive system with a PE regressor; this implies that the tracking-error convergence is exponential for a large class of overparameterized adaptive feedforward systems.
	www.nasatech.com /Briefs/Mar98/NPO20183.html (739 words)

	LTI Approach to Adaptive Narrow-Band Feedforward Control
		Such controllers are used, for example, to suppress harmonic noise and vibrations; the basic idea is to track disturbance tones actively and "notch" them by use of high-gain feedback to achieve large attenuation.
		The theory is characterized as "unified" because it produces, as special cases, all known instances of LTI adaptive feedforward systems previously reported in the literature.
		The theory generalizes the previous results by showing this class of LTI adaptive systems to be considerably larger than it was known to be.
	www.nasatech.com /Briefs/Mar98/NPO20184.html (690 words)

	aaron.homeunix.com (Site not responding. Last check: 2007-11-05)
		Almost everyone agrees of the great benefit that feedforward provides is great disturbance rejection capabilities.
		However almost everyone also agrees that feedforward is practically un-useful due to the accuracy needed for the model.
		This opens up a branch of research direction which has been for the most part been overlooked due to the impracticality of the need of a good plant model.
	aaron.homeunix.com /csu/cact/research/control/alg/adrc/lit/feedforward/feedforward.html (262 words)

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