Use Of Time Delay Research Articles

A Module-Based Telepractice Intervention for Parents of Children with Developmental Disabilities.

In the current study, we describe a study of the Internet-based Parent-implemented Communication Strategies-Storybook (i-PiCSS). I-PiCSS is an intervention program designed to train and coach parents to use evidence-based naturalistic communication teaching (NCT) strategies (i.e., modeling, mand-model, and time delay) and reading techniques while reading storybooks with their young children with disabilities. Three participating parents were trained via online modules and coached via telepractice technologies (videoconferences). Zoom videoconference software was used for all coaching sessions. Using a single case multiple-baseline design across NCT strategies within each family, we examined, (a) parents' fidelity use of the three NCT strategies, (b) parents' use of book reading techniques, and (c) child language and communication outcomes. After self-directed training and remote coaching, parents used modeling, mand-model, and time delay strategies with higher rates and fidelity (accuracy). Children initiated more communicative acts upon parents' use of time delay and increased their numbers of single-and multiple-word responses.

A Parent-Implemented Shared Reading Intervention via Telepractice

We describe a study of the internet-based Parent-Implemented Communication Strategies–Storybook (i-PiCSS), an intervention designed to train and coach parents to use evidenced-based naturalistic communication teaching (NCT) strategies (i.e., modeling, mand-model, and time delay) and RTs while reading storybooks with their young children with disabilities. Three participating parents were trained and coached via telepractice technologies (videoconferences, video editing software). Zoom software was used for videoconferencing and Camtasia software was used to record the training and coaching sessions and to edit the recorded session for feedback delivery purposes. Using a single-case multiple-baseline design across NCT strategies within each family, we examined (a) parents’ fidelity use of the three NCT strategies, (b) parents’ use of book RTs, and (c) child language and communication outcomes. The entire intervention period lasted 8 weeks. After training and coaching, parents used the modeling, mand-model, and time delay strategies with higher rates and higher quality (accuracy). Children initiated more communicative acts upon parents’ use of time delay and increased their numbers of single- and multiple-word responses.

A Parent-Implemented Shared-Reading Intervention to Promote Communication Skills of Preschoolers with Autism Spectrum Disorder

In the current study, we examined the effect of a parent-implemented early communication intervention during shared book reading. Three mothers of children with autism spectrum disorder were trained and coached to use a set of reading techniques and evidenced-based naturalistic communication teaching strategies (i.e., modeling, mand-model, and time delay). Using a multiple-baseline design across behaviors, the following three components were examined: (a) the mothers' use of reading techniques with fidelity, (b) the mothers' rate and fidelity in using the three naturalistic teaching strategies, and (c) the children's communication outcomes. After training and coaching, the mothers used the reading techniques and naturalistic teaching strategies with high fidelity. The children initiated more communicative acts upon their mothers' use of time delay.

Parent-Implemented Communication Strategies During Storybook Reading

Children with developmental disabilities (DD) may experience delays in their ability to speak and communicate with their parents, peers, and others. These children often benefit from evidence-based, parent-implemented communication interventions. In the current study, two mothers were trained and coached to use storybook reading techniques and evidence-based naturalistic communication teaching strategies (i.e., modeling, mand-model, and time delay) while reading books with their children with DD. Using a multiple-baseline design across naturalistic teaching strategies, the following three components were examined: (a) mothers’ use of book reading techniques, (b) mothers’ rate and fidelity in using the three naturalistic teaching strategies, and (c) children’s communication outcomes. After training and coaching, the mothers used the modeling, mand-model, and time delay strategies with higher rates and higher fidelity. The children initiated more communicative acts upon their mothers’ use of time delay. The mothers reported that the training and coaching helped them implement the strategies and led to improvements in their children’s communication skills.

Hidden data transmission using time delay for separating useful signals from masking oscillations

A new method of hidden data transmission based on the use of time delay for the separation of useful signals from masking noise-like (chaotic or stochastic) oscillations is described. Mathematical models involving a source of chaotic oscillations have been studied using numerical methods. The transmission of a masked non-encoded signal and the pulsed data transmission using 0/1 bit code are considered.

‘Delay scheduling’, an unconventional use of time delay for trajectory tracking

A basic trajectory tracking exercise is conducted on a linear time invariant (LTI) dynamics with a fixed control law. The feedback considered here, however, is affected by a time delay, τ, which maybe uncertain. Interestingly, time delayed LTI systems may exhibit multiple stable operating regions in the space of the delay. However, systematic, exact and exhaustive determination of these regions is, mathematically speaking, still a challenging problem. The contribution of this paper is three fold. First, to deploy a recent framework called Cluster Treatment of Characteristic Roots (CTCR) and experimentally verify the stability regions. Second, to establish an unconventional control law, called the “ delay scheduling” procedure, to use the time delay as a control parameter. Third, to determine the best (“optimum” in certain respect) time delay value(s) rendering the most desirable tracking characteristics.

Twenty‐four hour predictions of f0F2 using time delay neural networks

The use of time delay feed‐forward neural networks to predict the hourly values of the ionospheric F2 layer critical frequency, f0F2, 24 hours ahead, have been examined. The 24 measurements of f0F2 per day are reduced to five coefficients with principal component analysis. A time delay line of these coefficients is then used as input to a feed‐forward neural network. Also included in the input are the 10.7 cm solar flux and the geomagnetic index Ap. The network is trained to predict measured f0F2 data from 1965 to 1985 at Slough ionospheric station and validated on an independent validation set from the same station for the periods 1987–1990 and 1992–1994. The results are compared with two different autocorrelation methods for the years 1986 and 1991, which correspond to low and high solar activity, respectively.

Scanning moiré and phase shifting with time delay and integration imaging

Scanning moiré is generated by undersampling of a phase-modulated grating pattern. In projection profilometry the scanning moiré pattern represents equal height and depth contours on a test object. By use of time delay and integration (TDI) imaging, it is possible to generate an on-line scanning moiré pattern from the complete periphery of a rotating cylindrical object. For automated phase and profile unwrapping from scanning moiré fringes, phase-shifting interferometry techniques are most desirable. However, lack of spatial information in the undersampled scanning moiré fringes introduces serious errors in phase unwrapping. We report a method that uses oversupply of data to balance the effect of undersampling. This oversupply is achieved with a TDI feature that permits programmable image magnification in the scanning direction.

Generalized synchronization of chaos in directionally coupled chaotic systems.

Synchronization of chaotic systems is frequently taken to mean actual equality of the variables of the coupled systems as they evolve in time. We explore a generalization of this condition, which equates dynamical variables from one subsystem with a function of the variables of another subsystem. This means that synchronization implies a collapse of the overall evolution onto a subspace of the system attractor in full space. We explore this idea in systems where a response system [bold y]([ital t]) is driven with the output of a driving system [bold x]([ital t]), but there is no feedback to the driver. We lose generality but gain tractability with this restriction. To investigate the existence of the synchronization condition [bold y]([ital t])=[phi]([bold x]([ital t])) we introduce the idea of mutual false nearest neighbors to determine when closeness in response space implies closeness in driving space. The synchronization condition also implies that the response dynamics is determined by the drive alone, and we provide tests for this as well. Examples are drawn from computer simulations on various known cases of synchronization and on data from nonlinear electrical circuits. Determining the presence of generalized synchronization will be quite important when one has only scalarmore » observations from the drive and from the response systems since the use of time delay (or other) embedding methods will produce imperfect'' coordinates in which strict equality of the synchronized variables is unlikely to transpire.« less

Time delay estimation in continuous linear time-invariant systems

The use of a time delay in modeling LTI systems is quite common. However, attempts to estimate these time delays in continuous systems typically resorted to methods which increase the number of parameters in the system, in contradiction to the use of time delay in the model to begin with. We present here an attempt to estimate the time delays directly. The algorithm we present is supported both by analysis and simulations with very encouraging results.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Improving instruction for adults with developmental disabilities: Evaluation of a staff training package

AbstractImprovements in adaptive behavior among adults with developmental disabilities often depends on the quality of instruction delivered by direct‐care staff. The present study evaluated the effectiveness of a multifaceted package for improving the quality of instructional interactions among three staff/adult dyads. Instructional interactions were first analyzed to identify areas for improvement. A multifaceted intervention package consisting of inservice training, participative management, and on‐going feedback was then implemented in a multiple‐baseline design across dyads. The package trained staff to increase their use of time delay and reinforcement strategies and these changes were associated with greater independence in a sandwich making task among two of the three participating adults. The results suggest direct observation of existing instructional interactions may provide valuable information when training staff to implement effective habilitative programs for adults with developmental disabilities.

INCREASING AUTISTIC CHILDREN'S DAILY SPONTANEOUS SPEECH

We investigated the effectiveness of teaching parents of 3 autistic boys to use a time delay procedure to increase their children's appropriate spontaneous speech in several naturally occurring daily settings (e.g., saying "good morning" in the morning). Generalization across settings and within settings across persons and locations was assessed. Variation in the children's spontaneous speech was also assessed. In addition procedural errors in the parents' use of time delay were calculated. Results indicated that all children increased their daily spontaneous speech and generalized their speech to other locations and persons.

Beamforming experiments with a cylindrical array using real (vice complex) shading coefficients

A method of beamforming which utilizes real shading (without the use of time delay or phase shift networks) of the element outputs in a cylindrical hydrophone array was tested. Narrow beam patterns formed from the outputs of a 29.62‐wavelength‐diameter cylinder of elements space 2° apart are compared with the prediction of the mathematical model presented in a companion paper. The accuracy of the prediction is illustrated by close comparison with measurements made to evaluate the effects of shading coefficient errors, focusing, and frequency response.