scholarly journals Determination and verification of the calculated model parameters of salt rocks taking into account softening and plastic flow

2021 ◽  
Vol 247 ◽  
pp. 1-7
Author(s):  
Evgenii Kozlovskiy ◽  
Mikhail Zhuravkov
Keyword(s):  
Comparative Analysis ◽  
Friction Coefficient ◽  
Laboratory Tests ◽  
Salt Rocks ◽  
Burgers Model ◽  
Underground Mine Workings ◽  
Coulomb Model ◽  
Mine Workings ◽  
Calculated Model

The article suggests using a combination of the modified Burgers model and the Mohr – Coulomb model with the degradation of the adhesion coefficient and the increase in the friction coefficient to determine the parameters of salt rocks. A comparative analysis of long-term laboratory tests and field observations in underground mine workings with the results obtained using a calculated model with certain parameters is carried out. The parameters of the Mohr – Coulomb model with the degradation of the adhesion coefficient and the increase in the friction coefficient were obtained from the statistically processed data of laboratory tests, and the parameters of the modified Burgers model were determined. Using numerical methods, virtual (computer) axisymmetric triaxial tests, both instantaneous and long-term, were performed on the basis of the proposed model with selected parameters. A model problem is solved for comparing the behavior of the model with the data of observation stations in underground mine workings obtained from borehole rod extensometers and contour deformation marks. The analytically obtained coefficients of the nonlinear viscous element of the modified Burgers model for all the analyzed salt rocks did not need to be corrected based on the monitoring results. At the same time, optimization was required for the viscoelastic element coefficients for all the considered rocks. The analysis of the model studies showed a satisfactory convergence with the data on the observation stations. The comparative analysis carried out on the models based on laboratory tests and observations in the workings indicates the correct determination of the parameters for salt rocks and the verification of the model in general.

REHABILITATION OF HISTORICAL UNDERGROUND MINE WORKINGS—A PHASED APPROACH

2019 ◽  
Vol 5 (1) ◽  
pp. 25-42
Author(s):  
Sue Longo
Keyword(s):  
Hazard Mitigation ◽  
Underground Mine ◽  
Underground Mine Workings ◽  
Mine Workings ◽  
Mitigation Techniques ◽  
Mine Sites

INTRODUCTION Rehabilitation is essential in legacy mines as mine hazards do not improve with time; they will always get worse. Most hazard mitigation techniques address immediate risk but do nothing to actually fix the problem. The current impetus is to move away from simply identifying and managing risks and towards long-term solutions that eliminate the hazards in a planned way. This article will describe a proven approach to identify and eliminate hazards in such a way as to preserve the positive legacy of mining while eliminating issues that affect the environment and communities in proximity to legacy mine sites.

scholarly journals Classifying the Biological Status of Honeybee Workers Using Gas Sensors

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 166
Author(s):  
Jakub T. Wilk ◽  
Beata Bąk ◽  
Piotr Artiemjew ◽  
Jerzy Wilde ◽  
Maciej Siuda
Keyword(s):  
Gas Sensors ◽  
Laboratory Tests ◽  
Test Chamber ◽  
Ambient Air ◽  
True Positive Rate ◽  
True Positive ◽  
Positive Rate ◽  
Parameters Of Accuracy ◽  
Selection Of

Honeybee workers have a specific smell depending on the age of workers and the biological status of the colony. Laboratory tests were carried out at the Department of Apiculture at UWM Olsztyn, using gas sensors installed in two twin prototype multi-sensor detectors. The study aimed to compare the responses of sensors to the odor of old worker bees (3–6 weeks old), young ones (0–1 days old), and those from long-term queenless colonies. From the experimental colonies, 10 samples of 100 workers were taken for each group and placed successively in the research chambers for the duration of the study. Old workers came from outer nest combs, young workers from hatching out brood in an incubator, and laying worker bees from long-term queenless colonies from brood combs (with laying worker bee’s eggs, humped brood, and drones). Each probe was measured for 10 min, and then immediately for another 10 min ambient air was given to regenerate sensors. The results were analyzed using 10 different classifiers. Research has shown that the devices can distinguish between the biological status of bees. The effectiveness of distinguishing between classes, determined by the parameters of accuracy balanced and true positive rate, of 0.763 and 0.742 in the case of the best euclidean.1nn classifier, may be satisfactory in the context of practical beekeeping. Depending on the environment accompanying the tested objects (a type of insert in the test chamber), the introduction of other classifiers as well as baseline correction methods may be considered, while the selection of the appropriate classifier for the task may be of great importance for the effectiveness of the classification.

scholarly journals The Effects of CSR Activities on Business According to Employee Perception

2021 ◽  
pp. 1-22
Author(s):  
Anđelka Stojanović ◽  
Natalija Sofranova ◽  
Sanela Arsić ◽  
Isidora Milošević ◽  
Ivan Mihajlović
Keyword(s):  
Job Satisfaction ◽  
Factor Analysis ◽  
Corporate Social Responsibility ◽  
Comparative Analysis ◽  
Confirmatory Factor Analysis ◽  
Confirmatory Factor ◽  
Different Dimensions ◽  
Corporate Social ◽  
Vital Element

Corporate social responsibility (CSR) has become a vital element for building a long-term relationship with a company’s stakeholders. Different dimensions of a company’s social initiatives in terms of internal and external CSR activities influence the satisfaction of employees with the purpose of improving the CSR application. The aim of this research is to examine the level of employees’ awareness of the implementation of CSR in Serbian and Russian companies. A comparative analysis between these two countries was carried out in order to perceive the differences in attitudes of employees, their job satisfaction, and consequently the implementation of CSR. The hypotheses of the developed model were tested by using the Multi-group Confirmatory Factor Analysis. The obtained results offered several implications for scholars and practitioners that should be considered when formulating and implementing CSR actions.

scholarly journals Is the use of intra-operative blood salvage autotransfusion in hepatocellular carcinoma liver transplantation safe? A comparative analysis of long-term outcomes

HPB ◽  
2019 ◽  
Vol 21 ◽  
pp. S366
Author(s):  
Kah Wai Lai ◽  
Jarrod Tan ◽  
Glenn Bonney ◽  
Iyer Shridhar ◽  
Krishnakumar Madhavan ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Liver Transplantation ◽  
Comparative Analysis ◽  
Long Term Outcomes ◽  
Blood Salvage

Stability Evaluation of Old and Unapproachable Underground Mine Workings below Surface Structures

2019 ◽  
Vol 93 (3) ◽  
pp. 351-359 ◽  
Author(s):  
Angad Kushwaha ◽  
Subhashish Tewari ◽  
Prabhat Kumar Mandal ◽  
Rana Bhattacharjee ◽  
Arka Jyoti Das ◽  
...  
Keyword(s):  
Underground Mine ◽  
Surface Structures ◽  
Stability Evaluation ◽  
Underground Mine Workings ◽  
Mine Workings

scholarly journals Comparative analysis of the long-term effect of two families of high-flux polysulfone dialysers on platelet count: a retrospective cross-sectional study

2017 ◽  
Vol Volume 13 ◽  
pp. 1415-1422 ◽  
Author(s):  
Rosaria Del Giorno ◽  
Lorenzo Berwert ◽  
Silvio Pianca ◽  
Giorgia Bianchi ◽  
Olivier Giannini ◽  
...  
Keyword(s):  
Platelet Count ◽  
Comparative Analysis ◽  
Cross Sectional Study ◽  
Term Effect ◽  
High Flux ◽  
Sectional Study ◽  
Cross Sectional ◽  
Long Term Effect

scholarly journals Organization, operations, and success of environmental organized crime in Italy and India: A comparative analysis

2016 ◽  
Vol 14 (2) ◽  
pp. 160-182 ◽  
Author(s):  
Aunshul Rege ◽  
Anita Lavorgna
Keyword(s):  
Comparative Analysis ◽  
Organized Crime ◽  
Research Area ◽  
Sand Mining ◽  
Short And Long Term ◽  
Operational Practices ◽  
Organized Crime Groups ◽  
Organizational Mechanisms ◽  
Environmental Crimes

Despite the devastating short- and long-term consequences of resource-related environmental crimes, rampant illegal soil and sand mining continues worldwide. In countries such as India and Italy, organized crime groups have emerged as prominent illegal suppliers of soil and sand. The proposed study focuses on an understudied research area at the intersection between organized crime and environmental crimes, and offers a trans-comparative study of illegal soil and sand mining conducted by Indian and Italian organized crime groups with two main objectives. First, a comparative analysis of the organizational mechanisms, operational practices, threat management, and supporting cultural, regulatory, and policing factors is conducted. Second, a discussion of how these groups reflect mainstream models and theories of organized crime is offered.

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