A practical method of estimating the time-varying degree of vowel nasalization from acoustic features

This paper investigates the problem of decentralized model reference adaptive control (MRAC) for a class of large-scale systems with time-varying delays in the interconnected terms and state and input delays. The upper bounds of interconnection terms with time-varying delays and external disturbances are assumed to be completely unknown. By integrators inclusion, a dynamic input delay compensator is established for input delay compensation and it is used as a practical method for state calculation x(t + R). Also, a method is presented for a class of decentralized feedback controllers, which can evolve the closed-loop system error uniformly bounded stable. As a numerical example, the proposed technique is applied to an unstable open-loop system to show the feasibility and effectiveness of the method.

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Accelerated Life Test Modeling of Outdoor Optical Products with Time-Varying Multi-Stresses

Journal of the IEST ◽

10.17764/jiet.51.2.g751061r06t68867 ◽

2008 ◽

Vol 51 (2) ◽

pp. 42-54

Author(s):

Chung Lam ◽

Huairui Guo

Keyword(s):

Life Stress ◽

Practical Method ◽

Temperature Cycling ◽

Accelerated Life Test ◽

Indoor Environments ◽

Time Varying ◽

Temperature And Humidity ◽

Cost Calculations ◽

Log Linear ◽

Term Performance

The long-term performance prediction of optical products deployed outdoors is important. The accuracy of the prediction directly affects warranty cost calculations. In indoor environments, products are generally operated under controlled temperature and humidity. However, products outdoors usually experience multiple stresses that continuously vary with time. An outdoor-use optical product, such as a fiber distribution hub cabinet with splitters, connectors, and fan-outs built in, will experience temperature cycling effects and varying humidity. Therefore, time-varying temperature and humidity are considered as major stresses acting on outdoor-use optical products. This study proposes a practical method that uses design of experiment (DOE) techniques and generalized log-linear (GLL) life-stress relationship to predict the life of outdoor optical products. The proposed method can consider the cumulative damage caused by time-varying temperature and humidity and was applied to predict the warranty return of an outdoor optical product.

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Identification of Unknown, Time-Varying Forces/Moments in Dynamics and Vibration Problems Using a New Approach To Deconvolution

Shock and Vibration ◽

10.1155/1998/415028 ◽

1998 ◽

Vol 5 (3) ◽

pp. 181-197 ◽

Cited By ~ 8

Author(s):

C.D. Johnson

Keyword(s):

Practical Method ◽

General Purpose ◽

Basis Functions ◽

Time Varying ◽

Force Moment ◽

Time Variations ◽

Vibration Problems ◽

Real Time Identification ◽

Weighting Coefficients ◽

Dynamics And Vibration

In this paper an alternative approach to the classical deconvolution idea is used to obtain a new and practical method for real-time identification of unknown, time-varying forces/moments in a general class of linear (linearized) dynamics and vibration problems with multiple-inputs and multiple-measurements. This new method for force/moment identification is unique in the respect that the uncertainty in the force/moment time-variations is not characterized by random-process methods, but rather by a generalized spline-model with totally unknown weighting coefficients and completely known basis-functions. The basis-functions are custom chosen in each application to reflect, qualitatively, the known characteristics of the force/moment time-variations to be identified. The method does not involve explicit identification of the unknown weighting coefficients. General-purpose identification algorithms for both continuous-time and discrete-time measurements are developed, and a worked example including computer simulation results is presented.

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Some acoustic features of nasal and nasalized vowels: A target for vowel nasalization

The Journal of the Acoustical Society of America ◽

10.1121/1.414967 ◽

1996 ◽

Vol 99 (6) ◽

pp. 3694-3706 ◽

Cited By ~ 40

Author(s):

Gang Feng ◽

Eric Castelli

Keyword(s):

Acoustic Features ◽

Vowel Nasalization

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The role of differential phase contrast in electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108027 ◽

1978 ◽

Vol 36 (1) ◽

pp. 176-177

Author(s):

E.M. Waddell ◽

J.N. Chapman ◽

R.P. Ferrier

Keyword(s):

Phase Contrast ◽

Practical Method ◽

Position Vector ◽

Differential Phase ◽

Pure Phase ◽

Differential Phase Contrast ◽

The Difference ◽

Image Position ◽

First Moment

Dekkers and de Lang (1977) have discussed a practical method of realising differential phase contrast in a STEM. The method involves taking the difference signal from two semi-circular detectors placed symmetrically about the optic axis and subtending the same angle (2α) at the specimen as that of the cone of illumination. Such a system, or an obvious generalisation of it, namely a quadrant detector, has the characteristic of responding to the gradient of the phase of the specimen transmittance. In this paper we shall compare the performance of this type of system with that of a first moment detector (Waddell et al.1977).For a first moment detector the response function R(k) is of the form R(k) = ck where c is a constant, k is a position vector in the detector plane and the vector nature of R(k)indicates that two signals are produced. This type of system would produce an image signal given bywhere the specimen transmittance is given by a (r) exp (iϕ (r), r is a position vector in object space, ro the position of the probe, ⊛ represents a convolution integral and it has been assumed that we have a coherent probe, with a complex disturbance of the form b(r-ro) exp (iζ (r-ro)). Thus the image signal for a pure phase object imaged in a STEM using a first moment detector is b2 ⊛ ▽ø. Note that this puts no restrictions on the magnitude of the variation of the phase function, but does assume an infinite detector.

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