Algebraische Ableitungsschätzung im Kontext der Rekonstruierbarkeit (Algebraic Time-derivative Estimation in the Context of Reconstructibility)

The main cause of the disagreement between the actual and calculated output data of hydraulic percussion mining machines is the erroneous feed of manipulation signals by the control units. For the maximal fitting of the calculated and actual figures, the continuous method of control action using the third time derivative of the law of motion of the main function element is accepted, namely, the accuracy. The mathematical models of control using displacement, velocity and acceleration are developed. The service factors of mining machines are found. Based on the theory of control and the mathematical logic theory, the logical circuits of formation of manipulation signals in each phase of the working cycle are developed. The main elements are converters, integrators and accumulators ensuring decomposition of elements of the logical circuits and further generation of appropriate control action. It is found that the simplest way is to generate the control action for acceleration of the key function element. For the developed circuits, it is recommended to use general charts of the control action change, implementable for a certain design of hydraulic percussion cutting heads in certain operating conditions.

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An approximate solution by the Galerkin method of a quasilinear equation with a boundary condition containing the time derivative of the unknown function

10.1063/5.0057126 ◽

2021 ◽

Author(s):

Alisher Mamatov ◽

Sayfiddin Bakhramov ◽

Alibek Narmamatov

Keyword(s):

Boundary Condition ◽

Approximate Solution ◽

Galerkin Method ◽

Unknown Function ◽

Quasilinear Equation ◽

Time Derivative ◽

The Galerkin Method

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1-Soliton solutions of the (2 + 1)-dimensional Heisenberg ferromagnetic spin chain model with the beta time derivative

Optical and Quantum Electronics ◽

10.1007/s11082-021-02739-9 ◽

2021 ◽

Vol 53 (2) ◽

Cited By ~ 1

Author(s):

K. Hosseini ◽

L. Kaur ◽

M. Mirzazadeh ◽

H. M. Baskonus

Keyword(s):

Spin Chain ◽

Time Derivative ◽

Soliton Solutions ◽

Chain Model ◽

Heisenberg Ferromagnetic Spin Chain ◽

Spin Chain Model

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Assessing Stability of Crutch Users by Non-Contact Methods

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18063001 ◽

2021 ◽

Vol 18 (6) ◽

pp. 3001

Author(s):

Achilles Vairis ◽

Suzana Brown ◽

Maurice Bess ◽

Kyu Hyun Bae ◽

Jonathan Boyack

Keyword(s):

Signal To Noise Ratio ◽

Time Derivative ◽

Assistive Devices ◽

Signal To Noise ◽

Physically Disabled ◽

Significant Difference ◽

Novice Users ◽

Noise Ratio ◽

Physically Disabled People

Enhancing gait stability in people who use crutches is paramount for their health. With the significant difference in gait compared to users who do not require an assistive device, the use of standard gait analysis tools to measure movement for temporary crush users and physically disabled people proves to be more challenging. In this paper, a novel approach based on video analysis is proposed as non-contact low-cost solution to the more expensive alternative with the data collected from processed videos, two values are calculated: the Signal to Noise Ratio (SNR) of acceleration, and the Signal to Noise Ratio of the jerk (time derivative of acceleration), to assess the user’s stability while they walk with crutches. The adopted methodology has been tested on a total of 10 participants. Five are temporary users of assistive devices with one being a long-term user and the other four novice users, and five are disabled participants who use those assistive devices permanently. Preliminary results show differences between novice users, long-term users, and physically disabled users. The approach is promising and could improve the assessment of crutch user stability, allowing for the correction of gait for individuals while using an inexpensive non-contact setup and preventing unnecessary falls.

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