Research and Application of Open-Off Cut Roof Cutting Pressure Releasing Technology

The first weighting control is one of the difficult problems that cannot be avoided in the safe and efficient production of longwall mining face. To optimize the existing pressure releasing technology of open-off cut, the open-off cut roof cutting pressure releasing (OCRCPR) technology is put forward on the basis of roof cutting pressure releasing gob-side entry retaining (RCPRGER) technology. Firstly, the mechanism of the technology and the design method of related key parameters are summarized. Then the pressure releasing effect of OCRCPR and the stress environment change under this technology are analyzed by mechanics calculation and numerical simulation, respectively, which verify the feasibility of the OCRCPR technology from the theoretical level. Finally, a test mining face is taken as an example to implement the field test. The field test results show that the OCRCPR can effectively shorten the first weighting step and weaken the first weighting strength and has a good pressure releasing effect.

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Long Term Field Test Results of Experimental EPDM and PUF Roofing

10.21236/ada226197 ◽

1990 ◽

Author(s):

David M. Bailey ◽

Stuart D. Foltz ◽

Myer J. Rosenfield

Keyword(s):

Field Test ◽

Test Results ◽

Term Field

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Identifying Personality Disorders that are Security Risks: Field Test Results

10.21236/ada564011 ◽

2011 ◽

Cited By ~ 3

Author(s):

Olga G. Shechter ◽

Eric L. Lang

Keyword(s):

Personality Disorders ◽

Field Test ◽

Test Results ◽

Security Risks

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Experimental Study on Quadruped Wheel Robot for Wheat Precision Seeding

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.693.1651 ◽

2016 ◽

Vol 693 ◽

pp. 1651-1657 ◽

Cited By ~ 1

Author(s):

Hai Bo Lin ◽

Chui Jie Yi ◽

Zun Min Liu

Keyword(s):

Experimental Study ◽

Field Test ◽

Design Method ◽

Operating Conditions ◽

High Yield ◽

Orthogonal Rotation ◽

Agricultural Machine ◽

Main Factors ◽

Multiple Effort

The wheat precision seeding technology provided an advanced agricultural protection for the high yield of wheat. But the lack of an effective agricultural machine made this technology difficult to apply widely. In this paper a quadruped wheel robot to achieve the wheat precision seeding technology was designed. And experimental study was taken under different operating conditions. Because of multiple effort factors, a quadratic orthogonal rotation combination design method was applied in the experiments, and identifying the main factors by analysis. Then the field test was carried out according to the main factors. The experiment results showed that the qualified rates of seeding exceed 93% in different sowing speed. That reached the agronomic requirements of wheat precision seeding.

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Estimation of Outdoor PM2.5 Infiltration into Multifamily Homes Depending on Building Characteristics Using Regression Models

Sustainability ◽

10.3390/su13105708 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5708

Author(s):

Bo-Ram Park ◽

Ye-Seul Eom ◽

Dong-Hee Choi ◽

Dong-Hwa Kang

Keyword(s):

Regression Analysis ◽

Correlation Analysis ◽

Field Test ◽

Outer Surface ◽

Regression Models ◽

Field Tests ◽

Test Results ◽

Correlation And Regression Analysis ◽

Building Characteristics ◽

Pm2.5 Concentration

The purpose of this study was to evaluate outdoor PM2.5 infiltration into multifamily homes according to the building characteristics using regression models. Field test results from 23 multifamily homes were analyzed to investigate the infiltration factor and building characteristics including floor area, volume, outer surface area, building age, and airtightness. Correlation and regression analysis were then conducted to identify the building factor that is most strongly associated with the infiltration of outdoor PM2.5. The field tests revealed that the average PM2.5 infiltration factor was 0.71 (±0.19). The correlation analysis of the building characteristics and PM2.5 infiltration factor revealed that building airtightness metrics (ACH50, ELA/FA, and NL) had a statistically significant (p < 0.05) positive correlation (r = 0.70, 0.69, and 0.68, respectively) with the infiltration factor. Following the correlation analysis, a regression model for predicting PM2.5 infiltration based on the ACH50 airtightness index was proposed. The study confirmed that the outdoor-origin PM2.5 concentration in highly leaky units could be up to 1.59 times higher than that in airtight units.

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Field Test Results in Malaysia Wells of a New-Generation Slim Pulsed Neutron Logging Tool

10.2118/186957-ms ◽

2017 ◽

Cited By ~ 1

Author(s):

P. Millot ◽

F. K. Wong ◽

D. A. Rose ◽

T. Zhou ◽

R. Grover ◽

...

Keyword(s):

Field Test ◽

Test Results ◽

New Generation ◽

Pulsed Neutron ◽

Logging Tool

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High GLR ESP Technologies Comparison, Field Test Results (Russian)

10.2118/117414-ru ◽

2008 ◽

Cited By ~ 2

Author(s):

V.G. Bedrin ◽

M.M. Khasanov ◽

R.A. Khabibullin ◽

V.A. Krasnov ◽

A.A. Pashali ◽

...

Keyword(s):

Field Test ◽

Test Results ◽

Comparison Field

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Real-Ear Measurements in Conductive Hearing Loss: Discrepancies Between Probe-Tube Microphone Measurements and Sound Field Test Results

British Journal of Audiology ◽

10.3109/03005364000000064 ◽

1998 ◽

Vol 32 (3) ◽

pp. 205-209

Author(s):

Valerie C. G. Cleaver

Keyword(s):

Hearing Loss ◽

Field Test ◽

Conductive Hearing Loss ◽

Sound Field ◽

Test Results ◽

Conductive Hearing

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Tests and Analyses of Slotted-In Steel-Plate Connections in Composite Timber Shear Wall Panels

Advances in Civil Engineering ◽

10.1155/2017/7259014 ◽

2017 ◽

Vol 2017 ◽

pp. 1-20

Author(s):

Ulf Arne Girhammar ◽

Bo Källsner

Keyword(s):

Bearing Capacity ◽

Failure Modes ◽

Design Method ◽

Shear Walls ◽

Test Results ◽

Horizontal Shear ◽

Load Bearing Capacity ◽

Wood Panel ◽

Load Bearing ◽

Plate Connections

The authors present an experimental and analytical study of slotted-in connections for joining walls in the Masonite flexible building (MFB) system. These connections are used for splicing wall elements and for tying down uplifting forces and resisting horizontal shear forces in stabilizing walls. The connection plates are inserted in a perimeter slot in the PlyBoard™ panel (a composite laminated wood panel) and fixed mechanically with screw fasteners. The load-bearing capacity of the slotted-in connection is determined experimentally and derived analytically for different failure modes. The test results show ductile postpeak load-slip characteristics, indicating that a plastic design method can be applied to calculate the horizontal load-bearing capacity of this type of shear walls.

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