Regularized Extremal Shift in Problems of Stable Control

This paper proposes a passivity theorem on the basis of energy concepts to study the stability of force feedback in a virtual haptic system. An impedance-passivity controller (IPC) was designed from the two-port network perspective to improve the chief drawback of haptic systems, namely the considerable time required to reach stability if the equipment consumes energy slowly. The proposed IPC can be used to achieve stability through model parameter selection and to obtain control gain. In particular, haptic performance can be improved for extreme cases of high stiffness and negative damping. Furthermore, a virtual training system for one-degree-of-freedom sticking was developed to validate the experimental platform of our IPC. To ensure consistency in the experiment, we designed a specialized mechanical robot to replace human operation. Finally, compared with basic passivity control systems, our IPC could achieve stable control rapidly.

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Investigation of the Preparation of Anodized Nanoporous Alumina Array

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.887-888.766 ◽

2014 ◽

Vol 887-888 ◽

pp. 766-769 ◽

Cited By ~ 1

Author(s):

Huey Ling Chang ◽

Chih Ming Chen ◽

Chin Huang Sun ◽

Jin Shyong Lin

Keyword(s):

Anodic Oxidation ◽

Self Assembly ◽

Aluminum Surface ◽

Nanostructured Film ◽

Oxidation Treatment ◽

Anodic Aluminum ◽

Nanoporous Template ◽

Anodic Oxidation Treatment ◽

Stable Control

This study produced a regularly arranged membrane, called anodic aluminum oxide (referred AAO), by mean of anodic oxidation treatment. The structure of AAO can be molecular self-assembly and its pore size is consistent. Also, the manufacturing process cost is low. These properties make the AAO be a nanotemplate material. This study further created a high quality of nanostructured film by electrochemical mould with the design of electrolyzer. In addition, a uniform nanothin film was grown on the aluminum surface in the stable control of current and temperature according to the conditions of different anode treatment. This film can form a nanopore array which the diameter can be controlled the size ranging from 15 nm to 400 nm. As results, the study can produce nanoporous template for various aperture by mean of anodic oxidation.

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Patch history, invertebrate patch dynamics and heterogeneous community composition: perspectives from a manipulative stream experiment

Marine and Freshwater Research ◽

10.1071/mf06202 ◽

2007 ◽

Vol 58 (4) ◽

pp. 307 ◽

Cited By ~ 8

Author(s):

D. A. Olsen ◽

C. D. Matthaei ◽

C. R. Townsend

Keyword(s):

Community Composition ◽

Patch Dynamics ◽

Invertebrate Drift ◽

Macroinvertebrate Communities ◽

Disturbance History ◽

Patch Type ◽

Entire Study ◽

Stream Communities ◽

Different Types ◽

Stable Control

Recent research after bed-moving flow events has shown that local disturbance history can contribute to patchiness in stream communities. Patterns of recolonisation were studied following experimental disturbances in which patches of sediment were manipulated by removing 10 cm of surface sediment (scour) or by depositing 10 cm of clean sediment (fill) on top of existing sediments. Six invertebrate samples were collected from each patch type (including stable control patches) on five occasions up to six weeks after the manipulation. Immediately after the disturbance, distinctive macroinvertebrate communities occurred in scour, fill and stable patches. Community composition in scour patches remained distinct from fill and stable patches for the entire study period. Immediately after the manipulation, scour patches contained higher densities of hypogean taxa than did fill patches, but this difference did not persist for long, indicating that the relict community had little influence on the subsequent pattern of recovery. In contrast, fill patch communities were indistinguishable from stable patches by Day 14, most likely owing to recolonisation by buried invertebrates and invertebrate drift. Differences in patterns of recolonisation following different types of disturbance can result in patchy invertebrate communities that persist for several weeks after the disturbance.

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The mechanics of biped running and a stable control strategy

Robotica ◽

10.1017/s0263574708005134 ◽

2008 ◽

Vol 27 (05) ◽

pp. 789 ◽

Cited By ~ 1

Author(s):

Muhammad E. Abdallah ◽

Kenneth J. Waldron

Keyword(s):

Control Strategy ◽

Stable Control

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A visual circuit uses complementary mechanisms to support transient and sustained pupil constriction

eLife ◽

10.7554/elife.15392 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 35

Author(s):

William Thomas Keenan ◽

Alan C Rupp ◽

Rachel A Ross ◽

Preethi Somasundaram ◽

Suja Hiriyanna ◽

...

Keyword(s):

Neural Coding ◽

Pupil Size ◽

Neural Circuit ◽

Ganglion Cells ◽

Retinal Ganglion ◽

Neural Basis ◽

Behavioral Dynamics ◽

Pupil Constriction ◽

Sustained Responses ◽

Stable Control

Rapid and stable control of pupil size in response to light is critical for vision, but the neural coding mechanisms remain unclear. Here, we investigated the neural basis of pupil control by monitoring pupil size across time while manipulating each photoreceptor input or neurotransmitter output of intrinsically photosensitive retinal ganglion cells (ipRGCs), a critical relay in the control of pupil size. We show that transient and sustained pupil responses are mediated by distinct photoreceptors and neurotransmitters. Transient responses utilize input from rod photoreceptors and output by the classical neurotransmitter glutamate, but adapt within minutes. In contrast, sustained responses are dominated by non-conventional signaling mechanisms: melanopsin phototransduction in ipRGCs and output by the neuropeptide PACAP, which provide stable pupil maintenance across the day. These results highlight a temporal switch in the coding mechanisms of a neural circuit to support proper behavioral dynamics.

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Topical problems of diabetes treatment during pregnancy

Diabetes Mellitus ◽

10.14341/2072-0351-5701 ◽

2009 ◽

Vol 12 (4) ◽

pp. 32-36

Author(s):

Irina Yur'evna Demidova ◽

Natalya Yur'evna Arbatskaya ◽

Elena Petrovna Mel'nikova

Keyword(s):

Diabetes Mellitus ◽

Blood Glucose ◽

Insulin Therapy ◽

Pregnant Women ◽

Intensive Insulin Therapy ◽

Insulin Requirement ◽

Subcutaneous Insulin ◽

Diabetes Treatment ◽

Self Monitoring ◽

Stable Control

The main causes behind decompensation of diabetes mellitus (DM) in pregnant women are consid-ered, such as metabolic and hormonal disturbancesinfluencing insulin requirement in different periods of pregnancy and variability of glycemia related to pharmacokinetic and pharmacodynamicproperties of insu-lin preparations. Recommended target levels of glycemia in pregnant women with DM are cited. The fre-quencyof self-monitoring blood glucose and principles of intensive insulin therapy are discussed. Advan-tages of continuous subcutaneous insulin infusionand its role in the maintenance of stable control of car-bohydrate metabolism during pregnancy are discussed.

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Condition Absolute Stability Control System of Electromagnetoelastic Actuator for Communication Equipment

Transactions on Networks and Communications ◽

10.14738/tnc.81.7775 ◽

2020 ◽

Vol 8 (1) ◽

pp. 08-15 ◽

Cited By ~ 1

Author(s):

Sergey Mikhailovich Afonin

Keyword(s):

Control System ◽

Absolute Stability ◽

Stability Control ◽

Straight Line ◽

Stability Control System ◽

Stationary Set ◽

The Absolute ◽

Communication Equipment ◽

Stable Control

We obtained the condition absolute stability on the derivative for the control system of electromagnetoelastic actuator for communication equipment. We applied the frequency methods for Lyapunov stable control system to calculate the condition absolute stability control system of electromagnetoelastic actuator. We used Yakubovich criterion absolute stability system with the condition on the derivative. The aim of this work is to determine the condition of the absolute stability on the derivative for the control system of electromagnetoelastic actuator. We received the stationary set of the control system of the hysteresis deformation of the electromagnetoelastic actuator. The stationary set is the segment of the straight line.

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