Influence of two masticating conditions on assessment of movement path stability

The appropriate choice of a threshold level, which separates the tails of the probability distribution of a random variable from its middle part, is considered to be a very complex and challenging task. This paper provides an empirical study on various methods of the optimal tail selection in risk measurement. The results indicate which method may be useful in practice for investors and financial and regulatory institutions. Some methods that perform well in simulation studies, based on theoretical distributions, may not perform well when real data are in use. We analyze twelve methods with different parameters for forty-eight world indices using returns from the period of 2000–Q1 2020 and four sub-periods. The research objective is to compare the methods and to identify those which can be recognized as useful in risk measurement. The results suggest that only four tail selection methods, i.e., the Path Stability algorithm, the minimization of the Asymptotic Mean Squared Error approach, the automated Eyeball method with carefully selected tuning parameters and the Hall single bootstrap procedure may be useful in practical applications.

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We Wonder Why We Wallow: Impacts of Trim Error on Speed and Flight Path Stability

AIAA Scitech 2019 Forum ◽

10.2514/6.2019-0559 ◽

2019 ◽

Author(s):

Mathew Delisle ◽

Timothy T. Takahashi

Keyword(s):

Flight Path ◽

Path Stability

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Study on the effective discharge energy mechanism of vertical ultrasonic vibration assisted EDM processing

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/09544054211028527 ◽

2021 ◽

pp. 095440542110285

Author(s):

Yinghuai Dong ◽

Guangyan Li ◽

Yan Wang ◽

Jianbao Song ◽

Shuo Yang ◽

...

Keyword(s):

Ultrasonic Vibration ◽

Theoretical Research ◽

Discharge Energy ◽

Movement Path ◽

Energy Mechanism ◽

Effective Discharge ◽

Parameter Matching ◽

Discharge Gap ◽

Conventional Machining

Compared to traditional EDM processing, UEDM (Ultrasonic Vibration Assisted EDM) have a great improvement in optimizing discharge environment. In this study, ultrasonic vibration is attached to the electrode. According to the relative positional relationship between the movement path of the electrode tip and the discharge gap, four working states of UEDM are defined. The four working states are the path within the discharge gap, the path in contact with the edge of the discharge gap, part of the electrode end path outside the discharge gap, and the path in contact with the workpiece, respectively. States are analyzed from the effective discharge energy and discharge frequency. A mathematical model for effective discharge energy and surface roughness is established for two conventional working states. The correctness of the theoretical research is verified by experiments. As the experiment results shown, the influence of ultrasonic amplitude on the energy of UEDM is primary, while frequency is secondary. A working state with better discharge stability and higher discharge energy when the electrode end path is in contact with the edge of the discharge gap. In the first three conventional machining states, the surface quality of the workpiece increases with the increase of ultrasonic amplitude and frequency. The study can provide scientific guidance for parameter matching of UEDM.

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Novel strategies for path stability estimation under topology change using Hello messaging in MANETs

Ad Hoc Networks ◽

10.1016/j.adhoc.2018.12.005 ◽

2019 ◽

Vol 87 ◽

pp. 76-99 ◽

Cited By ~ 5

Author(s):

Alamgir Naushad ◽

Ghulam Abbas ◽

Ziaul Haq Abbas ◽

Aris Pagourtzis

Keyword(s):

Topology Change ◽

Stability Estimation ◽

Path Stability

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Stability of Masticatory Movement Path in Normal Subjects.

Nihon Hotetsu Shika Gakkai Zasshi ◽

10.2186/jjps.39.1036 ◽

1995 ◽

Vol 39 (6) ◽

pp. 1036-1042

Author(s):

Keita Sumiyoshi ◽

Takahiro Ogawa ◽

Kiyoshi Koyano ◽

Yoshihiro Tsukiyama ◽

Tsuneo Suetsugu

Keyword(s):

Normal Subjects ◽

Movement Path ◽

Masticatory Movement

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A System for Acoustic Field Measurement Employing Cartesian Robot

Metrology and Measurement Systems ◽

10.1515/mms-2016-0037 ◽

2016 ◽

Vol 23 (3) ◽

pp. 333-343 ◽

Cited By ~ 1

Author(s):

Maciej Szczodrak ◽

Adam Kurowski ◽

Józef Kotus ◽

Andrzej Czyżewski ◽

Bożena Kostek

Keyword(s):

Acoustic Field ◽

Energy Flow ◽

Velocity Vector ◽

Sound Pressure ◽

Sound Field ◽

Acoustic Energy ◽

The Other ◽

Object Shape ◽

Movement Path ◽

Optimum Path

AbstractA system setup for measurements of acoustic field, together with the results of 3D visualisations of acoustic energy flow are presented in the paper. Spatial sampling of the field is performed by a Cartesian robot. Automatization of the measurement process is achieved with the use of a specialized control system. The method is based on measuring the sound pressure (scalar) and particle velocity(vector) quantities. The aim of the system is to collect data with a high precision and repeatability. The system is employed for measurements of acoustic energy flow in the proximity of an artificial head in an anechoic chamber. In the measurement setup an algorithm for generation of the probe movement path is included. The algorithm finds the optimum path of the robot movement, taking into account a given 3D object shape present in the measurement space. The results are presented for two cases, first without any obstacle and the other - with an artificial head in the sound field.

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