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Article
Publication date: 1 August 1999

Uri Fidelman

Suggests that the arousability theory of intelligence and personality of Robinson (1996) lacks two important factors: the influence of neural transmission errors and of…

Abstract

Suggests that the arousability theory of intelligence and personality of Robinson (1996) lacks two important factors: the influence of neural transmission errors and of hemisphericity on intelligence and personality. It is considered that at least two factors contribute to intelligence. The first factor is the potential energetic level of Hebb’s engrams, which may be related to arousability. The second factor is the probability of neural transmission errors. It is suggested that the theory of H.J. Eysenck, that a neural message is sent repeatedly until it is accepted identically a certain number of times, which is smaller for more intelligent subjects, is correct.

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Kybernetes, vol. 28 no. 6/7
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 1 June 1997

David L. Robinson and Jaafar Behbehani

Considers the thesis that intelligence differences and EEG‐intelligence correlations can both be explained in terms of differences in the frequency of neural transmission

Abstract

Considers the thesis that intelligence differences and EEG‐intelligence correlations can both be explained in terms of differences in the frequency of neural transmission errors. Considers an alternative theory which holds that intelligence variance and correlated EEG variance are both caused by variation of cerebral arousability. Refers to technical and methodological problems that bedevil the EEG‐intelligence literature and measurement difficulties that have arisen through lack of adequate concepts. Concludes that the principal measurement problems derive from failure to appreciate the important distinction that must be made between “cerebral arousal” and “cerebral arousability”; and that any useful EEG‐intelligence concept must go beyond vague and general ideas such as “neural efficiency” or “neural transmission errors” to explain how EEG differences relate to differences in brain function that can account for the main facts recorded in the intelligence literature.

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Kybernetes, vol. 26 no. 4
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 21 June 2011

Yeon Taek Oh

Angular errors in the robot axes can make a significant contribution to robot positioning accuracy. This paper seeks to propose a new measuring method for measuring angular errors.

Abstract

Purpose

Angular errors in the robot axes can make a significant contribution to robot positioning accuracy. This paper seeks to propose a new measuring method for measuring angular errors.

Design/methodology/approach

New techniques were devised for the detailed investigation of joint angular errors using a reference encoder together with a precision electronic level and autocollimator. This equipment enabled vertical and horizontally orientated joint axes to be measured with the robot located on‐site. Circle contouring measurements were also undertaken to assess the significance of multi‐axis movements on the accuracy of the end effector.

Findings

The technique, devised using a simulation program for the robot geometry with results from a circular test, enables robot errors to be characterised in terms of datum location error, backlash, gear transmission error, axes misalignments and joint encoder offset.

Originality/value

The paper describes the experimental and theoretical accuracy characteristics of an articulated industrial robot. Close correlation was obtained between the experimental and theoretical results. This paper offers the practical robot calibration method for industrial application.

Details

Industrial Robot: An International Journal, vol. 38 no. 4
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 2 March 2015

Jadwiga Malgorzata Pisula and Mieczyslaw Plocica

– The purpose of this article is to present a method for the analysis of the quality of the bevel gear at the development level.

Abstract

Purpose

The purpose of this article is to present a method for the analysis of the quality of the bevel gear at the development level.

Design/methodology/approach

A non-commercial aircraft bevel gear design support system was developed. The system utilises matrix and vector calculi to model the technological machining systems and to analyse the contact of the designed pair. Both the technological model and the design model offer the possibility of manipulating the calculated parameters. This enables independent selection of the pinion/gear engagement, making it possible to achieved the desired contact pattern (its shape, position and size) and/or minimise motion transmission deviation. This article presents an analysis of the meshing of the aircraft transmission designed in two variants.

Findings

The newly developed non-commercial transmission design support system offers the capability to freely adjust mesh quality indicators. The first step is to perform automated technological calculations for a specific geometry of gear members, on the basis of which gear and pinion flanks are developed. Then, numerical models of tooth flanks are configured in the designed pair, and tooth mesh quality is verified. Quality indicators are provided in the form of summary contact pattern and the motion graph. In the subsequent step, changes are made to basic geometry of pinion tooth flank. After satisfactory mesh indicators have been reached, the transmission is tested for assembly errors and additional corrections are made to the geometry of the pinion tooth surface, as required. The above methodology guarantees that the assumed quality indicators are achieved on the physically cut transmission.

Practical implications

Fast preparation of the technology with guaranteed high mesh quality is a significant factor in the competitiveness of an industrial plant which implements a new bevel gear in its manufacturing activities.

Originality/value

The visualisation of the results of the use of the application allows the user to easily interpret the analysed contact pattern and take appropriate decisions as to the necessity of making corrections.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 87 no. 2
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 13 March 2017

Yuxiang Chen, Mutellip Ahmat and Zhong-tang Huo

Irregular windy loads are loaded for a wind turbine. This paper aims to determine the form of gear failure and the working life of the gear system by assessing the dynamic…

Abstract

Purpose

Irregular windy loads are loaded for a wind turbine. This paper aims to determine the form of gear failure and the working life of the gear system by assessing the dynamic strength of gears and dynamic stress distribution.

Design/methodology/approach

The helical planetary gear system of the wind turbine growth rate gearbox was investigated, and while a variety of clearance and friction gear meshing processes were considered in the planetary gear system, a finite element model was built based on the contact–impact dynamics theory, solved using the explicit algorithm. The impact stress of the sun gear of the planetary gear system was calculated under different loads. An integrated planetary gear meshing stiffness, and the error of system dynamic transmission error were investigated when the planetary gear meshes with the sun or ring gears.

Findings

The load has little effect on the sun gear of the impact stress which was known. The varying stiffness is different while the planetary gear meshes with the sun and ring gears. There were differences between the planetary gear system and the planetary gear, and with load, the planetary gear transmission error decreases.

Originality/value

This study will provide basis knowledge for the planetary gear system.

Details

Industrial Lubrication and Tribology, vol. 69 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 June 1998

Uri Fidelman

Robinson and Behbehani (1997) contended against Fidelman (1996) and argued that neural transmission errors influence neither EEG nor intelligence. They also contended the…

Abstract

Robinson and Behbehani (1997) contended against Fidelman (1996) and argued that neural transmission errors influence neither EEG nor intelligence. They also contended the suggestion of Fidelman (1996) that the mean hemisphericity of a sample may determine the sign of the correlation between IQ and the averaged evoked potentials (AEP) measures of string length and amplitude. These contentions are answered.

Details

Kybernetes, vol. 27 no. 4
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 12 March 2018

Chris K. Mechefske, David Benjamin Rapos and Markus Timusk

The purpose of this paper is to report the findings of a study that used measurements of shaft relative rotational position, made using inexpensive Hall Effect sensors and…

Abstract

Purpose

The purpose of this paper is to report the findings of a study that used measurements of shaft relative rotational position, made using inexpensive Hall Effect sensors and magnets mounted at the ends of a gearbox input and output shafts, to determine gear “transmission variance.” The transmission variance signals, as a function of gear/shaft rotational position, were then used to detect and diagnose gear faults.

Design/methodology/approach

Two sets of spur gears (one plastic and one steel) were used to experimentally determine the relative shaft rotational position between the input and the output gearbox shafts. Fault-free and faulted (damaged tooth faces and cracked tooth bases) gears were used to collect representative dynamic signals. Signal processing was used to extract transmission variance values as a function of shaft rotational position and then used to detect and diagnose gear faults.

Findings

The results show that variations in the relative rotational position of the output shaft relative to that of the input shaft (the transmission variance) can be used to reveal gear mesh characteristics, including faults, such as cracked or missing gear teeth and flattened gear tooth faces, in both plastic gears and steel gears under appropriate (realistic) loads and speeds.

Research limitations/implications

The operational mode of the non-contact rotational position sensors and the dynamic accuracy limitations are explained along with the basic signal processing required to extract transmission variance values.

Practical implications

The results show that shaft rotational position measurements can be made accurately and precisely using relatively inexpensive sensors and can subsequently reveal gear faults.

Social implications

The inexpensive and yet trustworthy fault detection methodology developed in this work should help to improve the efficiency of maintenance actions on gearboxes and, therefore, improve the overall industrial efficiency of society.

Originality/value

The method described has distinct advantages over traditional analysis methods based on gearbox vibration and/or oil analysis.

Details

Journal of Quality in Maintenance Engineering, vol. 24 no. 1
Type: Research Article
ISSN: 1355-2511

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Article
Publication date: 1 January 1985

Ray Denenberg

The need for standards allowing computer‐to‐computer communication, and examples of technical issues are discussed. The framework of the Open Systems Interconnection…

Abstract

The need for standards allowing computer‐to‐computer communication, and examples of technical issues are discussed. The framework of the Open Systems Interconnection Reference Model, consisting of seven layers, each performing a distinct and defined function, is explained and illustrated. Sidebars feature: 1) public data networks and X.25, 2) OSI standards, and 3) the OSI layer functions. A glossary is included.

Details

Library Hi Tech, vol. 3 no. 1
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 27 March 2020

Yan Xia, Yi Wan, Hongwei Wang and Zhanqiang Liu

As the transmission component of a locomotive, the traction gear pair system has a direct effect on the stability and reliability of the whole machine. This paper aims to…

Abstract

Purpose

As the transmission component of a locomotive, the traction gear pair system has a direct effect on the stability and reliability of the whole machine. This paper aims to provide a detailed dynamic analysis for the traction system under internal and external excitations by numerical simulation.

Design/methodology/approach

A non-linear dynamic model of locomotive traction gear pair system is proposed, where the comprehensive time-varying meshing stiffness is obtained through the Ishikawa formula method and verified by the energy method, and then the sliding friction excitation is analyzed based on the location of the contact line. Meantime, the adhesion torque is constructed as a function of the adhesion-slip feature between wheelset and rail. Through Runge–Kutta numerical method, the system responses are studied with varying bifurcation parameters consisting of exciting frequency, load fluctuation, gear backlash, error fluctuation and friction coefficient. The dynamic behaviors of the system are analyzed and discussed from bifurcation diagram, time history, spectrum plot, phase portrait, Poincaré map and three-dimensional frequency spectrum.

Findings

The analysis results reveal that as control parameters vary the system experiences complex transition among a diverse range of motion states such as one-periodic, multi-periodic and chaotic motions. Specifically, the significant difference in system bifurcation characteristics can be observed under different adhesion conditions. The suitable gear backlash and error fluctuation can avoid the chaotic motion, and thus, reduce the vibration amplitude of the system. Similarly, the increasing friction coefficient can also suppress the unstable state and improve the stability of the system.

Originality/value

The numerical results may provide a systemic understanding of dynamic characteristics and present some available information to design and optimize the transmission performance of the locomotive traction system.

Details

Engineering Computations, vol. 37 no. 8
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 April 2002

Uri Fidelman

It is suggested that the left hemispheric neurons and the magnocellular visual system are specialized in tasks requiring a relatively small number of large neurons having…

Abstract

It is suggested that the left hemispheric neurons and the magnocellular visual system are specialized in tasks requiring a relatively small number of large neurons having a fast reaction time due to a high firing rate or many dendritic synapses of the same neuron which are activated simultaneously. On the other hand the right hemispheric neurons and the neurons of the parvocellular visual system are specialized in tasks requiring a relatively larger number of short term memory (STM) Hebbian engrams (neural networks). This larger number of engrams is achieved by a combination of two strategies. The first is evolving a larger number of neurons, which may be smaller and have a lower firing rate. The second is evolving longer and more branching axons and thus producing more engrams, including engrams comprising neurons located at cortical areas distant from each other. This model explains why verbal functions of the brain are related to the left hemisphere, and the division of semantic tasks between the left hemisphere and the right one. This explanation is extended to other cognitive functions like visual search, ontological cognition, the detection of temporal order, and the dual cognitive interpretation of the perceived physical phenomena.

Details

Kybernetes, vol. 31 no. 3/4
Type: Research Article
ISSN: 0368-492X

Keywords

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