Identification of damage development in the core of steel cord belts with the diagnostic system

AbstractBelt conveyors are used for transporting bulk materials over distances. The core of the belt, by transferring the longitudinal stresses and ensuring proper frictional coupling of the belt, enables belt movement and transportation of materials on its surface. As the belt cover and edges are used, the belt becomes abraded, and the core is subject to fatigue. The result is the development of cracks in rubber covers across the belt, which leads to the development of damage not only along the cables (the natural direction of water migration and corrosion) but also in the direction transverse to the belt axis. Conducting a series of scans of the St-type belt operating in one of the underground copper ore mines in Poland allowed identifying the number of failures as well as their size and changes over time. These data were in turn used to determine the measures defining the condition of the belt such as the density of defects (the number of defects per 1 m of the belt), the density of the area of damage (the area of damage per 1 m of the belt) and the change in the average area of a single defect over time. By determining the regression of these measures in time and the rate of damage development in both directions (along the axis of the belt and across the belt), it was possible to forecast future states of the belt, as well as to evaluate the costs of different belt replacement strategies and the economic rationalization of the decision to replace them. This research has become possible owing to the development of the DiagBelt system for two-dimensional imaging of the damage to the core of steel-cord belts with resolution sufficiently high to allow tracking the development of single core defects.

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Identification of damage development in the core of steel cord belts with the diagnostic system

10.21203/rs.3.rs-233490/v1 ◽

2021 ◽

Author(s):

Ryszard Blazej ◽

Leszek Jurdziak ◽

Agata Kirjanow-Blazej ◽

Tomasz Kozłowski

Keyword(s):

Diagnostic System ◽

Water Migration ◽

Damage Development ◽

Copper Ore ◽

The Core ◽

Single Defect ◽

Steel Cord ◽

Belt Conveyors ◽

Changes Over Time ◽

Over Time

Abstract Belt conveyors are used for transporting bulk materials over distances. The core of the belt, by transferring the longitudinal stresses and ensuring proper frictional coupling of the belt, enables belt movement and transportation of materials on its surface. As the belt cover and edges are used, the belt becomes abraded, and the core is subject to fatigue. The result is the development of cracks in rubber covers across the belt, which leads to the development of damage not only along the cables (the natural direction of water migration and corrosion) but also in the direction transverse to the belt axis. Conducting a series of scans of the St-type belt operating in one of the underground copper ore mines in Poland allowed identifying the number of failures as well as their size and changes over time. These data were in turn used to determine the measures defining the condition of the belt such as the density of defects (the number of defects per 1 m of the belt), the density of the area of damage (the area of damage per 1 m of the belt) and the change in the average area of a single defect over time. By determining the regression of these measures in time and the rate of damage development in both directions (along the axis of the belt and across the belt), it was possible to forecast future states of the belt, as well as to evaluate the costs of different belt replacement strategies and the economic rationalization of the decision to replace them. This research has become possible owing to the development of the DiagBelt system for two-dimensional imaging of the damage to the core of steel-cord belts with resolution sufficiently high to allow tracking the development of single core defects.

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Equality and Equity in Chinese Higher Education in the Post-massification Era: An Analysis Based on Chinese Scholarly Literature

The China Quarterly ◽

10.1017/s0305741020001241 ◽

2021 ◽

pp. 1-22

Author(s):

Qiang Zha

Keyword(s):

Higher Education ◽

Literature Review ◽

Bibliometric Analysis ◽

Chinese Higher Education ◽

Scholarly Literature ◽

The Core ◽

Research Questions ◽

Changes Over Time ◽

Core Issues ◽

Over Time

Abstract This paper examines several research questions relating to equality and equity in Chinese higher education via an extended literature review, which in turn sheds light on evolving scholarly explorations into this theme. First, in the post-massification era, has the Chinese situation of equality and equity in higher education improved or deteriorated since the late 1990s? Second, what are the core issues with respect to equality and equity in Chinese higher education? Third, how have those core issues evolved or changed over time and what does the evolution indicate and entail? Methodologically, this paper uses a bibliometric analysis to detect the topical hotspots in scholarly literature and their changes over time. The study then investigates each of those topical terrains against their temporal contexts in order to gain insights into the core issues.

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Constraints on holocene ice-thickness changes in central Greenland from the GISP2 ice-core data

Annals of Glaciology ◽

10.1017/s0260305500015561 ◽

1995 ◽

Vol 21 ◽

pp. 33-39 ◽

Cited By ~ 9

Author(s):

J. F. Bolzan ◽

E. D. Waddington ◽

R.B. Alley ◽

D.A. Meese

Keyword(s):

Inverse Method ◽

Accumulation Rate ◽

Ice Core ◽

Ice Sheet ◽

Ice Thickness ◽

The Core ◽

Ice Sheet Modeling ◽

Age Relation ◽

Changes Over Time ◽

Over Time

The depth–age relation observed in the GISP2 ice core is the result of the integrated effects of ice-sheet changes over time, as well as the accumulation-rate history. Here, we construct a forward model to compute ages at various depths in the core. In the model, these ages are functions of parameters that describe the ice thickness as a function of time. Using the maximum-likelihood inverse method, these parameters are iteratively adjusted until measured and computed ages agree satisfactorily. The results suggest that the thickness along the flowline connecting the GISP2 and GRIP drill sites has not changed significantly since the onset of the Holocene. We also derive bounds on the likely thickness changes. Because these bounds are independent of assumptions concerning the processes driving the ice-sheet evolution, they can provide useful constraints for other ice-sheet modeling efforts.

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The Role of Time in the Theory of Narrative Identity in the Philosophy of Paul Ricoeur

RUDN Journal of Philosophy ◽

10.22363/2313-2302-2021-25-3-483-494 ◽

2021 ◽

Vol 25 (3) ◽

pp. 483-494

Author(s):

Michał Kumorek

Keyword(s):

Personal Identity ◽

Narrative Identity ◽

The Other ◽

Human Being ◽

The Core ◽

Other Hand ◽

New Models ◽

Changes Over Time ◽

Over Time

Time has a very important function in considering the identity of a person. It is the factor that brings identity into question. The core of the problem is the question of whether the person is the same as he or she was at another time. The problem of personal identity was one of the most important issues in Paul Ricoeurs philosophy. He considers this problem in the context of time and notes that traditional models of identity as sameness and as selfhood have been entangled in various aporias. He, therefore, proposes two new models of identity that are related in different ways to temporality: character and promise. Character is a model that changes over time through the acquisition or loss of various traits. The promise, on the other hand, is a model that resists the pressure of time attempts to keep a given word. In this way, these two different models create the framework for Ricoeur's concept of narrative identity. In this concept, time enables the development of action in a story. It allows the action to turn around, but it also allows the human being to look at the story of his or her life. Character and promise are models that allow the human being to look at his or her life as a certain temporal entity that is constantly threatened by unforeseen accidents and events but also constantly absorbs them and, through to time, gives the possibility of retrospection leading to synthesis. This synthesis allows us to look at a single life as a whole, belonging to the same person endowed with the character and challenge of keeping a promise.

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Electrophysiology of the central and peripheral nervous systems

Oxford Textbook of Medicine ◽

10.1093/med/9780199204854.003.2432_update_001 ◽

2010 ◽

pp. 4752-4768

Author(s):

Christian Krarup

Keyword(s):

Nervous System ◽

Nerve Conduction Studies ◽

Pathological Examination ◽

Pathological Changes ◽

The Core ◽

Electrophysiological Studies ◽

The Central Nervous System ◽

Electrophysiological Findings ◽

Changes Over Time ◽

Over Time

Electrophysiological studies of the central nervous system and peripheral nervous system—the core investigations in clinical neurophysiology—include electroencephalography, evoked potentials, electromyography, and nerve conduction studies. These provide information from anatomical regions which may not be accessible to direct pathological examination, and are good for tracking changes over time. However, they do not provide direct information about pathological changes in the nervous system, hence it is often necessary to supplement electrophysiological findings by imaging or other laboratory studies, and it is mandatory to view all results in their clinical context....

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The university and social responsiveness in the curriculum: a new form of scholarship?

London Review of Education ◽

10.1080/14748460902990351 ◽

2009 ◽

Cited By ~ 6

Author(s):

Judith Favish ◽

Janice L. McMillan

Keyword(s):

Higher Education ◽

Research University ◽

Social Responsiveness ◽

The Core ◽

Valid Knowledge ◽

New Form ◽

University Of Cape Town ◽

The University ◽

Changes Over Time ◽

Over Time

Challenges facing the higher education sector globally include questions over what counts as knowledge and what are valid forms of both its reproduction and production. This paper addresses the question of how what counts as valid knowledge is challenged and how it changes over time. It does this via an analysis of examples of social responsiveness profiled as 'portraits of practice' in the annual social responsiveness reports produced at the University of Cape Town, South Africa, a traditionally strong research university. In this paper, we discuss and analyse key themes emerging from this work and argue that social responsiveness not only serves to enhance the core functions of teaching and research but can act to change them.

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Constraints on holocene ice-thickness changes in central Greenland from the GISP2 ice-core data

Annals of Glaciology ◽

10.3189/s0260305500015561 ◽

1995 ◽

Vol 21 ◽

pp. 33-39 ◽

Cited By ~ 1

Author(s):

J. F. Bolzan ◽

E. D. Waddington ◽

R.B. Alley ◽

D.A. Meese

Keyword(s):

Inverse Method ◽

Accumulation Rate ◽

Ice Core ◽

Ice Sheet ◽

Ice Thickness ◽

The Core ◽

Ice Sheet Modeling ◽

Age Relation ◽

Changes Over Time ◽

Over Time

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Comparison of two devices for measuring exercise transcutaneous oxygen pressures in patients with claudication

VASA ◽

10.1024/0301-1526/a000454 ◽

2015 ◽

Vol 44 (5) ◽

pp. 355-362 ◽

Cited By ~ 8

Author(s):

Marie Urban ◽

Alban Fouasson-Chailloux ◽

Isabelle Signolet ◽

Christophe Colas Ribas ◽

Mathieu Feuilloy ◽

...

Keyword(s):

Oxygen Pressure ◽

Optical Sensors ◽

Chemical Sensors ◽

Transcutaneous Oxygen ◽

Starting Values ◽

Two Systems ◽

Transcutaneous Oxygen Pressure ◽

New Sensors ◽

Changes Over Time ◽

Over Time

Abstract. Summary: Background: We aimed at estimating the agreement between the Medicap® (photo-optical) and Radiometer® (electro-chemical) sensors during exercise transcutaneous oxygen pressure (tcpO2) tests. Our hypothesis was that although absolute starting values (tcpO2rest: mean over 2 minutes) might be different, tcpO2-changes over time and the minimal value of the decrease from rest of oxygen pressure (DROPmin) results at exercise shall be concordant between the two systems. Patients and methods: Forty seven patients with arterial claudication (65 + / - 7 years) performed a treadmill test with 5 probes each of the electro-chemical and photo-optical devices simultaneously, one of each system on the chest, on each buttock and on each calf. Results: Seventeen Medicap® probes disconnected during the tests. tcpO2rest and DROPmin values were higher with Medicap® than with Radiometer®, by 13.7 + / - 17.1 mm Hg and 3.4 + / - 11.7 mm Hg, respectively. Despite the differences in absolute starting values, changes over time were similar between the two systems. The concordance between the two systems was approximately 70 % for classification of test results from DROPmin. Conclusions: Photo-optical sensors are promising alternatives to electro-chemical sensors for exercise oximetry, provided that miniaturisation and weight reduction of the new sensors are possible.

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