Investigation of the radial bearing force developed during actual ship operations. Part 1: Straight ahead sailing and turning maneuvers

Asperger syndrome (AS) is a form of high-functioning autism characterized by qualitative impairment in social interaction. People afflicted with AS typically have abnormal nonverbal behaviors which are often manifested by avoiding eye contact. Gaze constitutes an important interactional resource, and an AS person’s tendency to avoid eye contact may affect the fluidity of conversations and cause misunderstandings. For this reason, it is important to know the precise ways in which this avoidance is done, and in what ways it affects the interaction. The objective of this article is to describe the gaze behavior of preadolescent AS children in institutional multiparty conversations. Methodologically, the study is based on conversation analysis and a multimodal study of interaction. The findings show that three main patterns are used for avoiding eye contact: 1) fixing one’s gaze straight ahead; 2) letting one’s gaze wander around; and 3) looking at one’s own hands when speaking. The informants of this study do not look at the interlocutors at all in the beginning or the middle of their turn. However, sometimes they turn to look at the interlocutors at the end of their turn. This proves that these children are able to use gaze as a source of feedback. When listening, looking at the speaker also seems to be easier for them than looking at the listeners when speaking.

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On corrosion properties of ceramic materials for pump friction pairs in lead – bismuth environment

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2019-98-2-116-122 ◽

2019 ◽

pp. 116-122

Author(s):

V. V. Stepanov ◽

A. D. Kashtanov ◽

S. U. Shchutsky ◽

A. N. Agrinsky ◽

N. I. Simonov

Keyword(s):

Composite Materials ◽

Heat Resistance ◽

Experimental Research ◽

Ceramic Materials ◽

Operating Conditions ◽

Metallic Materials ◽

Corrosion Properties ◽

Liquid Coolant ◽

Radial Bearing ◽

Axial Pump

We consider the results of studies on the choice of material of the lower radial bearing of the pump, designed to circulate the coolant lead – bismuth. The circulation of the liquid coolant is provided by a vertical axial pump having a “long” shaft. In this design it is necessary to provide for the lower bearing the lubrication carried out with lead – bismuth coolant. Having analyzed the operating conditions of the axial pump, we decided to carry out the lower bearing in accordance with the scheme of a hydrodynamic sliding bearing. The materials of friction pairs in such a bearing must withstand the stresses arising from the operation of the pump, as well as the aggressive conditions of the coolant. Non-metallic materials – ceramics and carbon-based composite materials – were selected basing on the study of literature data for experimental research on the corrosion and heat resistance in the lead-bismuth environment.

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Research on Calculation of Bearing Force of Composite Insulation Cross Arm Pressure Rod of 220kV Power Transmission Line Pole Tower

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/546/2/022038 ◽

2020 ◽

Vol 546 ◽

pp. 022038

Author(s):

Haijun Xing ◽

Binrong Zhu ◽

Minjie Zhu ◽

Xingjie Wang ◽

Zhijun Zhang ◽

...

Keyword(s):

Transmission Line ◽

Power Transmission ◽

Power Transmission Line ◽

Bearing Force

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Research on combination of passive magnetic bearing and mechanical bearing for vertical axis wind turbine

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-201591 ◽

2021 ◽

pp. 1-16

Author(s):

Zhu Jun ◽

Zhang Zhenyi ◽

Cao Di ◽

Du Shaotong ◽

Guo Xiangwei ◽

...

Keyword(s):

Bearing Capacity ◽

Wind Turbine ◽

Stable State ◽

Vertical Axis ◽

Magnetic Bearing ◽

Suspension System ◽

Vertical Axis Wind Turbine ◽

Radial Bearing ◽

Stable Suspension ◽

Light Wind

Aiming at the “light wind start, light wind power generation” of vertical axis wind turbine, a new T-shaped radial passive magnetic bearing with high suspension characteristics is proposed. Passive magnetic bearings used in vertical axis wind turbines usually have small bearing capacity and difficult magnetization. The new T-shaped radial PMB can improve the radial bearing capacity, and the three magnetic rings all adopt simple axial magnetization. The new T-shaped radial PMB is combined with mechanical auxiliary bearing to form the suspension system of wind turbine. In the stable state, the suspension system can realize radial and axial stable suspension. The structure and working principle of the suspension system are briefly described. Through the finite element simulation, the characteristics of the new T-shaped radial PMB, the traditional double-ring PMB and the T-shaped PMBs are compared. Taking the high bearing capacity and high stiffness of the new T-shaped radial PMB as the optimization objective, the multi-objective optimization of the new T-shaped radial PMB was carried out by changing its geometric parameters (inner diameter, magnetization length and air gap). The research results show that: Under the same bearing capacity, the volume of the new T-shaped radial PMB is reduced by about 78.64%. Under the same volume, its bearing capacity increased by about 30.7%, and its stiffness increased by about 96.1%. After optimization, its radial bearing capacity increased to 101.38 N, and its stiffness increased to 202.76 N/mm.

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Misalignment in Gas Foil Journal Bearings: An Experimental Study

Volume 1: Aircraft Engine; Ceramics; Coal, Biomass and Alternative Fuels; Manufacturing, Materials and Metallurgy; Microturbines and Small Turbomachinery ◽

10.1115/gt2008-50806 ◽

2008 ◽

Cited By ~ 1

Author(s):

Samuel A. Howard

Keyword(s):

Journal Bearings ◽

System Level ◽

Design Parameters ◽

Foil Bearing ◽

Alignment System ◽

Successful Design ◽

Shaft Alignment ◽

Bearing Force ◽

Management Schemes ◽

Level Performance

As gas foil journal bearings become more prevalent in production machines, such as small gas turbine propulsion systems and microturbines, system level performance issues must be identified and quantified in order to provide for successful design practices. Several examples of system level design parameters that are not fully understood in foil bearing systems are thermal management schemes, alignment requirements, balance requirements, thrust load balancing, and others. In order to address some of these deficiencies and begin to develop guidelines, this paper presents a preliminary experimental investigation of the misalignment tolerance of gas foil journal bearing systems. Using a notional gas foil bearing supported rotor and a laser-based shaft alignment system, increasing levels of misalignment are imparted to the bearing supports while monitoring temperature at the bearing edges. The amount of misalignment that induces bearing failure is identified and compared to other conventional bearing types such as cylindrical roller bearings and angular contact ball bearings. Additionally, the dynamic response of the rotor indicates that the gas foil bearing force coefficients may be affected by misalignment.

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Calculation of the necessary level of external radial load for inner ring support on q rolling elements in a radial bearing with internal radial clearance

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2012.04.002 ◽

2012 ◽

Vol 60 (1) ◽

pp. 23-33 ◽

Cited By ~ 20

Author(s):

Radoslav Tomović

Keyword(s):

Radial Clearance ◽

Radial Load ◽

Radial Bearing ◽

Ring Support ◽

Rolling Elements

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Postural Preparation to Making a Step: Is There a “Motor Program” for Postural Preparation?

Journal of Applied Biomechanics ◽

10.1123/jab.23.4.261 ◽

2007 ◽

Vol 23 (4) ◽

pp. 261-274 ◽

Cited By ~ 7

Author(s):

Adriana M. Degani ◽

Alessander Danna-Dos-Santos ◽

Mark L. Latash

Keyword(s):

Reaction Time ◽

Simple Reaction Time ◽

Center Of Pressure ◽

Motor Program ◽

Whole Body ◽

Single Motor ◽

Simple Reaction ◽

Specific Manner ◽

Young Subjects ◽

Straight Ahead

We tested the hypothesis that a sequence of mechanical events occurs preceding a step that scales in time and magnitude as a whole in a task-specific manner, and is a reflection of a “motor program.” Young subjects made a step under three speed instructions and four tasks: stepping straight ahead, down a stair, up a stair, and over an obstacle. Larger center-of-pressure (COP) and force adjustments in the anteriorposterior direction and smaller COP and force adjustments in the mediolateral direction were seen during stepping forward and down a stair, as compared with the tasks of stepping up a stair and over an obstacle. These differences were accentuated during stepping under the simple reaction time instruction. These results speak against the hypothesis of a single motor program that would underlie postural preparation to stepping. They are more compatible with the reference configuration hypothesis of whole-body actions.

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Tuning of a Basic Coordination Pattern Constructs Straight-Ahead and Curved Walking in Humans

Journal of Neurophysiology ◽

10.1152/jn.00817.2003 ◽

2004 ◽

Vol 91 (4) ◽

pp. 1524-1535 ◽

Cited By ~ 96

Author(s):

Grégoire Courtine ◽

Marco Schieppati

Keyword(s):

Principal Components ◽

Lower Limb ◽

Time Course ◽

Body Movement ◽

The Body ◽

Whole Body ◽

Coordination Pattern ◽

Data Set ◽

Coordination Patterns ◽

Straight Ahead

We tested the hypothesis that common principles govern the production of the locomotor patterns for both straight-ahead and curved walking. Whole body movement recordings showed that continuous curved walking implies substantial, limb-specific changes in numerous gait descriptors. Principal component analysis (PCA) was used to uncover the spatiotemporal structure of coordination among lower limb segments. PCA revealed that the same kinematic law accounted for the coordination among lower limb segments during both straight-ahead and curved walking, in both the frontal and sagittal planes: turn-related changes in the complex behavior of the inner and outer limbs were captured in limb-specific adaptive tuning of coordination patterns. PCA was also performed on a data set including all elevation angles of limb segments and trunk, thus encompassing 13 degrees of freedom. The results showed that both straight-ahead and curved walking were low dimensional, given that 3 principal components accounted for more than 90% of data variance. Furthermore, the time course of the principal components was unchanged by curved walking, thereby indicating invariant coordination patterns among all body segments during straight-ahead and curved walking. Nevertheless, limb- and turn-dependent tuning of the coordination patterns encoded the adaptations of the limb kinematics to the actual direction of the walking body. Absence of vision had no significant effect on the intersegmental coordination during either straight-ahead or curved walking. Our findings indicate that kinematic laws, probably emerging from the interaction of spinal neural networks and mechanical oscillators, subserve the production of both straight-ahead and curved walking. During locomotion, the descending command tunes basic spinal networks so as to produce the changes in amplitude and phase relationships of the spinal output, sufficient to achieve the body turn.

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