On: Short note “Higher order autospectra by maximun entropy method”, by R. O. Plaisted and H. G. Peña (GEOPHYSICS, 48, 1409–1410, October, 1983).

Geophysics ◽  
1984 ◽  
Vol 49 (12) ◽  
pp. 2196-2197
Author(s):  
Toshifumi Matsuoka ◽  
Tad J. Ulrych
Keyword(s):  
Signal Processing ◽  
Short Note ◽  
Estimation Method ◽  
Difficult Problem ◽  
Higher Order ◽  
Entropy Method ◽  
Phase Estimation ◽  
Phase Information ◽  
Nonminimum Phase ◽  
Geophysical Signal

Recently Rosenblatt (1980) and Lii and Rosenblatt (1982) developed a phase estimation method for nonminimum phase MA processes by using the bispectrum which contains the required phase information of the wavelet. The computation of the bispectrum is, consequently, of importance in geophysical signal processing, particularly in the difficult problem of wavelet estimation.

To: “Higher order autospectra by maximum entropy method”, by R. O. Plaisted and H. G. Peña (GEOPHYSICS, 48, 1409–1410, October, 1983).

Geophysics ◽  
1985 ◽  
Vol 50 (4) ◽  
pp. 742-743
Keyword(s):  
Signal Processing ◽  
Maximum Entropy ◽  
Maximum Entropy Method ◽  
Estimation Method ◽  
Difficult Problem ◽  
Entropy Method ◽  
Phase Estimation ◽  
Phase Information ◽  
Nonminimum Phase ◽  
Geophysical Signal

Recently Rosenblatt (1980), Lii and Rosenblatt (1982), and Matsuoka and Ulrych (1984) developed a phase estimation method for nonminimum phase MA processes by using the bispectrum which contains the required phase information of the wavelet. The computation of the bispectrum is, consequently, of importance in geophysical signal processing, particularly in the difficult problem of wavelet estimation.

An Absolute Phase Estimation Method for Interferometry Imagery

2019 ◽  
Vol 1 (2) ◽  
pp. 14-19
Author(s):  
Sui Ping Lee ◽  
Yee Kit Chan ◽  
Tien Sze Lim
Keyword(s):  
Noise Suppression ◽  
Estimation Method ◽  
Phase Image ◽  
Phase Estimation ◽  
Phase Reconstruction ◽  
Estimation Algorithms ◽  
Absolute Phase ◽  
Filtering Rate ◽  
Interferometric Phase ◽  
Image Performance

Accurate interpretation of interferometric image requires an extremely challenging task based on actual phase reconstruction for incomplete noise observation. In spite of the establishment of comprehensive solutions, until now, a guaranteed means of solution method is yet to exist. The initially observed interferometric image is formed by 2π-periodic phase image that wrapped within (-π, π]. Such inverse problem is further corrupted by noise distortion and leads to the degradation of interferometric image. In order to overcome this, an effective algorithm that enables noise suppression and absolute phase reconstruction of interferometric phase image is proposed. The proposed method incorporates an improved order statistical filter that is able to adjust or vary on its filtering rate by adapting to phase noise level of relevant interferometric image. Performance of proposed method is evaluated and compared with other existing phase estimation algorithms. The comparison is based on a series of computer simulated and real interferometric data images. The experiment results illustrate the effectiveness and competency of the proposed method.

scholarly journals A multi-group higher-order factor analysis for studying the gender-effect in Teacher Job Satisfaction

METRON ◽  
2021 ◽  
Author(s):  
Carlo Cavicchia ◽  
Pasquale Sarnacchiaro
Keyword(s):  
Job Satisfaction ◽  
Factor Analysis ◽  
Secondary School Teachers ◽  
Estimation Method ◽  
Likelihood Estimation ◽  
Higher Order ◽  
Teacher Job Satisfaction ◽  
Public Secondary School ◽  
Order Factor ◽  
Maximum Likelihood Estimation Method

AbstractTeachers’ performances also depend on whether and how they are satisfied with their job. Therefore, Teacher Job Satisfaction must be considered as the driver of teachers’ accomplishments. To plan future policies and improve the overall teaching process, it is crucial to understand which factors mostly contribute to Teacher Job Satisfaction. A Common Assessment Framework and Education questionnaire was administered to 163 Italian public secondary school teachers to collect data, and a second-order factor analysis was used to detect which factors impact on Teacher Job Satisfaction, and to what extent. This model-based approach guarantees to detect factors which respect important properties: unidimensionality and reliability. All the coefficients are estimated according to the maximum likelihood estimation method in order to make inference on the parameters and on the validity of the model. Moreover, a new multi-group test for higher-order factor analysis was proposed and implemented. Finally, we analyzed in detail whether the factors impacting Teacher Job Satisfaction are characterized by gender.

Trajectory and Vibration Control of a Single-Link Flexible-Joint Manipulator Using a Distributed Higher-Order Differential Feedback Controller

2017 ◽  
Vol 139 (8) ◽  
Author(s):  
John T. Agee ◽  
Zafer Bingul ◽  
Selcuk Kizir
Keyword(s):  
Trajectory Tracking ◽  
Higher Order ◽  
Feedback Controller ◽  
Step Response ◽  
Position Measurement ◽  
Tracking Errors ◽  
Flexible Joint ◽  
Nonminimum Phase ◽  
Step Input ◽  
Flexible Joint Manipulator

The trajectory tracking in the flexible-joint manipulator (FJM) system becomes complicated since the flexibility of the joint of the FJM superimposes vibrations and nonminimum phase characteristics. In this paper, a distributed higher-order differential feedback controller (DHODFC) using the link and joint position measurement was developed to reduce joint vibration in step input response and to improve tracking behavior in reference trajectory tracking control. In contrast to the classical higher-order differential (HOD), the dynamics of the joint and link are considered separately in DHODFC. In order to validate the performance of the DHODFC, step input, trajectory tracking, and disturbance rejection experiments are conducted. In order to illustrate the differences between classical HOD and DHODFC, the performance of these controllers is compared based on tracking errors and energy of control signal in the tracking experiments and fundamental dynamic characteristics in the step response experiments. DHODFC produces better tracking errors with almost same control effort in the reference tracking experiments and a faster settling time, less or no overshoot, and higher robustness in the step input experiments. Dynamic behavior of DHODFC is examined in continuous and discontinues inputs. The experimental results showed that the DHODFC is successful in the elimination of the nonminimum phase dynamics, reducing overshoots in the tracking of such discontinuous input trajectories as step and square waveforms and the rapid damping of joint vibrations.

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