Results 21 - 30 of 129

• A New Method to Calculate Permeability of Gob for Air Leakage Calculations and for Improvements in Methane Control
  6/1/2010 - Conference papers
  This study demonstrates a fractal approach to calculating permeability of gob for air leakage that allows the calculation of porosity and permeability from the size distribution of broken rock material in the gob, which can be determined from image anal...
• Evaluation of Stiffeners for Reducing Noise from Horizontal Vibrating Screens
  4/1/2010 - Conference papers
  NIOSH is developing noise controls to reduce noise generated by horizontal vibrating screens. This paper documents testing of the stiffeners.
• Development of Multiple Regression Functions for Performance Prediction of Gob Gas Ventholes for Sealed and Active Longwall Mines
  2/1/2010 - Conference papers
  A discussion of the NIOSH-developed software suite for methane control and prediction (MCP) based on an artificial neural network (ANN) is presented in this paper.
• Studying Intake Airway Pressurization by Ventilation Modeling and Leakage Evaluation
  2/1/2010 - Conference papers
  This paper discusses the role of ventilation modeling in evaluating primary escapeway pressurization in a three-entry development system to improve emergency escape in a coal mine using belt air.
• Straight Line Walking and Path-Turn Identifying Algorithms for a Tracking Device Used in Underground Mines
  1/1/2010 - Conference papers
  This paper describes two algorithms that can provide greater accuracy for underground miner tracking systems.
• Structural Vibration as a Noise Source on Vibrating Screens
  11/1/2009 - Conference papers
  For horizontal vibrating screens, NIOSH testing indicates that the screen sides and feed box are dominant noise sources for the 250 Hz through 800 Hz one-third octave bands, while the electric motor is the most significant source for the 1 kHz band.
• Coal Bumps and Odd Dynamic Phenomena - A Numerical Investigation
  7/1/2009 - Conference papers
  This study extends the method of dynamic analysis to events driven by slip on geologic features.
• Deep Cover Pillar Recovery in the US
  7/1/2009 - Conference papers
  This paper provides an overview of current deep cover pillar recovery practice.
• Investigation into the Practical Use of Belt Air at US Longwall Operations
  2/1/2009 - Conference papers
  This paper discusses the current ventilation practices regarding the use of belt air during gateroad development and longwall panel extraction.
• Critical Review of Numerical Stress Analysis Tools for Deep Coal Longwall Panels Under Strong Strata
  2/1/2009 - Conference papers
  This report describes a study undertaken by NIOSH to more fully appreciate the application of numerical models in support of research on dynamic failure (bumps and bounces) in deep western coal mines.