In this paper, the advantage of using numerical models with the strength reduction method (SRM) to evaluate entry stability in complex multiple-seam conditions is demonstrated. A coal mine under variable topography from the Central Appalachian region is used as a case study. At this mine, unexpected roof conditions were encountered during development below previously mined panels. Stress mapping and observation of ground conditions were used to quantify the success of entry support systems in three room-and-pillar panels. Numerical model analyses were initially conducted to estimate the stresses induced by the multiple-seam mining at the locations of the affected entries. The SRM was used to quantify the stability factor of the supported roof of the entries at selected locations. The SRM-calculated stability factors were compared with observations made during the site visits, and the results demonstrate that the SRM adequately identifies the unexpected roof conditions in this complex case. It is concluded that the SRM can be used to effectively evaluate the likely success of roof supports and the stability condition of entries in coal mines.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5319427PMC
http://dx.doi.org/10.1016/j.ijmst.2015.12.003DOI Listing

Publication Analysis

Top Keywords

case study
8
coal mine
8
entry stability
8
strength reduction
8
reduction method
8
unexpected roof
8
roof conditions
8
stability
5
study multi-seam
4
multi-seam coal
4

Similar Publications

Introduction: COVID-19 has caused tremendous hardships and challenges around the globe. Due to the prevalence of asymptomatic and pre-symptomatic carriers, relying solely on disease testing to screen for infections is not entirely reliable, which may affect the accuracy of predictions about the pandemic trends. This study is dedicated to developing a predictive model aimed at estimating of the dynamics of COVID-19 at an early stage based on wastewater data, to assist in establishing an effective early warning system for disease control.

View Article and Find Full Text PDF

Background: Cutaneous melanoma is the leading cause of death from cutaneous malignancy and tends to metastasize lymphatically and hematogenously to the lung, liver, brain, and bone; it is a rare source of metastatic disease to the eye. Herein we provide a case report of cutaneous melanoma metastatic to the ciliary body and choroid involving clinical examination, slit lamp photography, and B-scan ultrasonography.

Result: A 55-year-old female with known metastatic cutaneous melanoma presented with pain, a large ciliochoroidal mass, visual decline, and diffuse intraocular inflammation.

View Article and Find Full Text PDF

Identify the underlying true model from other models for clinical practice using model performance measures.

BMC Med Res Methodol

January 2025

School of Mathematical Sciences, Xiamen University, Xiamen, 361005, People's Republic of China.

Objective: To assess whether the outcome generation true model could be identified from other candidate models for clinical practice with current conventional model performance measures considering various simulation scenarios and a CVD risk prediction as exemplar.

Study Design And Setting: Thousands of scenarios of true models were used to simulate clinical data, various candidate models and true models were trained on training datasets and then compared on testing datasets with 25 conventional use model performance measures. This consists of univariate simulation (179.

View Article and Find Full Text PDF

Rare diseases may affect the quality of life of patients and be life-threatening. Therapeutic opportunities are often limited, in part because of the lack of understanding of the molecular mechanisms underlying these diseases. This can be ascribed to the low prevalence of rare diseases and therefore the lower sample sizes available for research.

View Article and Find Full Text PDF

Background: Early esophageal fistula formation following anterior cervical spine surgery presents a formidable clinical challenge, necessitating astute rehabilitative nursing management. Such fistulas, if not promptly and effectively managed, can precipitate grave complications including mediastinitis, sepsis, respiratory failure, and, in severe instances, mortality. This underscores the critical need for immediate, comprehensive nursing interventions designed to mitigate these risks and enhance patient outcomes.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!