The Constitutive Relation of Crack-Weakened Rock Masses under Axial-Dimensional Unloading

This chapter focuses on temporality in managerial strategy making. It adopts an ‘in-time’ view to examine strategy making as the fluidity of the present experience and draws on a longitudinal, real-time study in a small Finnish software company. It shows five manifestations of ‘in-time’ processuality in strategy making, and identifies a temporality paradox that arises from the engagement of managers with two contradictory times: constructed linear ‘over time’ and experienced, becoming ‘in time’. These findings lead to the re-evaluation of the nature of intention in strategy making, and the authors elaborate the constitutive relation between time as ‘the passage of nature’ and human agency. Consequently, they argue that temporality should not be treated merely as an objective background or a subjective managerial orientation, but as a fundamental characteristic of processuality that defines the dynamics of strategy making.

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3D Thermal Monitoring of Jointed Rock Masses through Infrared Thermography and Photogrammetry

Remote Sensing ◽

10.3390/rs13050957 ◽

2021 ◽

Vol 13 (5) ◽

pp. 957

Author(s):

Guglielmo Grechi ◽

Matteo Fiorucci ◽

Gian Marco Marmoni ◽

Salvatore Martino

Keyword(s):

Surface Temperature ◽

Infrared Thermography ◽

Point Cloud ◽

Engineering Geology ◽

Point Clouds ◽

Jointed Rock ◽

Geometric Accuracy ◽

Rock Masses ◽

Natural Systems ◽

Temperature Distributions

The study of strain effects in thermally-forced rock masses has gathered growing interest from engineering geology researchers in the last decade. In this framework, digital photogrammetry and infrared thermography have become two of the most exploited remote surveying techniques in engineering geology applications because they can provide useful information concerning geomechanical and thermal conditions of these complex natural systems where the mechanical role of joints cannot be neglected. In this paper, a methodology is proposed for generating point clouds of rock masses prone to failure, combining the high geometric accuracy of RGB optical images and the thermal information derived by infrared thermography surveys. Multiple 3D thermal point clouds and a high-resolution RGB point cloud were separately generated and co-registered by acquiring thermograms at different times of the day and in different seasons using commercial software for Structure from Motion and point cloud analysis. Temperature attributes of thermal point clouds were merged with the reference high-resolution optical point cloud to obtain a composite 3D model storing accurate geometric information and multitemporal surface temperature distributions. The quality of merged point clouds was evaluated by comparing temperature distributions derived by 2D thermograms and 3D thermal models, with a view to estimating their accuracy in describing surface thermal fields. Moreover, a preliminary attempt was made to test the feasibility of this approach in investigating the thermal behavior of complex natural systems such as jointed rock masses by analyzing the spatial distribution and temporal evolution of surface temperature ranges under different climatic conditions. The obtained results show that despite the low resolution of the IR sensor, the geometric accuracy and the correspondence between 2D and 3D temperature measurements are high enough to consider 3D thermal point clouds suitable to describe surface temperature distributions and adequate for monitoring purposes of jointed rock mass.

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Simulation on hysteresis characteristic of squeeze mode magneto-rheological damper based on non-convex constitutive relation

Korea-Australia Rheology Journal ◽

10.1007/s13367-021-0020-2 ◽

2021 ◽

Vol 33 (3) ◽

pp. 261-271

Author(s):

Fan Wang ◽

Zi-Xiang Ying ◽

Lin-Xiang Wang

Keyword(s):

Constitutive Relation ◽

Hysteresis Characteristic ◽

Magneto Rheological

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