Linear solver performance in elastoplastic problem solution on GPU cluster

Introduction. Reliable forecasts of pillars geomechanical state are required to ensure rhythmic and safe work when mining a coal bed. Research aim is to construct a state model of the coal pillar located between the headways, based on the fundamental methods of elasticity theory and mechanics of a granular media, carry out a computational experiment within the model, and analyse the results. Methodology. The stress field in the coal pillar has been constructed in the course of solving the elastoplastic problem. By replacing the ultimately stressed marginal zone of the bed with the stresses which act within the zone, the problem has been reduced to the second exterior boundary value problem of elasticity theory and has been solved by the boundary element method. Ordinary and special Coulomb–Mohr criteria simultaneously fulfilled for the coal bed and rock mass contact are the criterion of the limit state onset. Actual pillar load is determined by integrating the vertical stress curve along the bed roof, which has been obtained from elastoplastic problem solution, while the ultimate load is determined from the condition that the whole pillar is in ultimately stressed state. Results. The dependence between the safety factor of the pillar between two identical headways, determined by V. D. Shevyakov method, and the growth of its width represents a graph in the form of a monotonically increasing curve. The curve flattens as soon as the depth increases. Summary. The results from the developed model of coal rock mass geomechanical state can be successfully used as coal pillar strength forecasts.

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In Search of Somatic Precursors of Spontaneous Insight

Journal of Psychophysiology ◽

10.1027/0269-8803/a000188 ◽

2018 ◽

Vol 32 (3) ◽

pp. 97-105 ◽

Cited By ~ 2

Author(s):

Wangbing Shen ◽

Yuan Yuan ◽

Chaoying Tang ◽

Chunhua Shi ◽

Chang Liu ◽

...

Keyword(s):

Problem Solving ◽

Direct Evidence ◽

Electrodermal Activity ◽

Cardiovascular Responses ◽

Solution Time ◽

Problem Solution ◽

Insight Problem ◽

Creative Insight ◽

Insight Problem Solving ◽

Analytic Problem

Abstract. A considerable number of behavioral and neuroscientific studies on insight problem solving have revealed behavioral and neural correlates of the dynamic insight process; however, somatic correlates, particularly somatic precursors of creative insight, remain undetermined. To characterize the somatic precursor of spontaneous insight, 22 healthy volunteers were recruited to solve the compound remote associate (CRA) task in which a problem can be solved by either an insight or an analytic strategy. The participants’ peripheral nervous activities, particularly electrodermal and cardiovascular responses, were continuously monitored and separately measured. The results revealed a greater skin conductance magnitude for insight trials than for non-insight trials in the 4-s time span prior to problem solutions and two marginally significant correlations between pre-solution heart rate variability (HRV) and the solution time of insight trials. Our findings provide the first direct evidence that spontaneous insight in problem solving is a somatically peculiar process that is distinct from the stepwise process of analytic problem solving and can be represented by a special somatic precursor, which is a stronger pre-solution electrodermal activity and a correlation between problem solution time and certain HRV indicators such as the root mean square successive difference (RMSSD).

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"Multiple Transfer Paradigms following Discrimination Problem Solution in Monkeys": Erratum.

Journal of Comparative and Physiological Psychology ◽

10.1037/h0020599 ◽

1969 ◽

Vol 67 (2, Pt.1) ◽

pp. 144-144

Author(s):

Michael Sledjeski ◽

Gilbert M. French

Keyword(s):

Discrimination Problem ◽

Problem Solution

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Hydrostatic Fiber Optic Liquid Level Sensor with position sensitive detector

Metrologiya ◽

10.32446/0132-4713.2020-4-38-51 ◽

2020 ◽

pp. 38-51

Author(s):

V. N. Astapov ◽

I. N. Kozlova

Keyword(s):

Fiber Optic ◽

Effective Area ◽

Raw Material ◽

Position Sensitive Detector ◽

Fiber Optic Sensor ◽

Liquid Level ◽

Problem Solution ◽

Sensitive Detector ◽

Position Sensitive ◽

Triangulation Sensor

This article presents the rationale and methodology for developing an intrinsically safe device, namely, a hydrostatic fiber optic sensor with a position-sensitive detector for monitoring the level of oil products in large-capacity tanks at oil depots and during pumping in a raw material warehouses. This device suitable for continuous monitoring of the liquid level, based on the measurement of a hydrostatic column of liquid with automatic offset of changes in the density of the liquid. Offset is carried out by means of a displacer (a fully submerged float), inside which a housing with a position-sensitive detector (PSD) is integrated. Theoretical validation of the bellows suspension usage for a displacer is given. During filling a container with a liquid whose level is measured, liquid bellows, the movement of which is recorded by an optical triangulation sensor using the reflected infrared ray incident on the bottom of the bellows. The principle of the triangulation sensor operation is based on the geometric properties of the triangles. The pulses of infrared radiation come through a fiber optic cable. In order to measure the movement of the surface (the bottom of the bellows) by measuring the movement of the reflected beam, a position-sensitive detector is used, which is located in a remote controller. In this device for the intrinsic safety problem solution, optical inputs of a fiber optic flat cable are located in the active zone of the sensor, which is connected to the optical inputs of a position-sensitive detector, operated on the principles of photoelectric effect. The light spot moving along the sensitive zone and converted by the detector into a one-dimensional signal proportional to the distance to the object. hydrostatically applies pressure over the entire effective area of the measuring

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