scholarly journals A Control Approach of the Roof in No-Pillar Roadway Formed by Roof Cutting and Pressure Releasing

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Qingnan Lou ◽  
Tingchun Li ◽  
Qingwen Zhu ◽  
Shanyuan Wu ◽  
Ming Yun ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Field Test ◽  
Theoretical Basis ◽  
Abutment Pressure ◽  
Mine Pressure ◽  
Control Approach ◽  
Test Study ◽  
Variation Range ◽  
Roadway Deformation ◽  
Support Cost

Roof control is one of the eternal themes of mine pressure theory, and it is also a key step of roadway formed by roof cutting. Based on the analysis of abutment pressure distribution, the viewpoint of controlling roadway roof by roof cutting distance is put forward according to the failure limit of roadway roof, and the calculation method of roof cutting distance is given. Based on the Qiuji coal mine’s background, the numerical and field test study is conducted to verify the theoretical analysis, and the allowable variation range of roof cutting distance is obtained. The research shows that the roof cutting distance, abutment pressure, and roadway deformation are closely related. By controlling the roof cutting distance, the roadway roof can be placed in the low-stress area, the roadway deformation can be reduced, and the support cost can be saved. This study provides a theoretical basis for explaining the roadway’s abnormal mine pressure and controlling the roadway roof by roof cutting.

IMOM Field Test Study and Accuracy Verification.

1998 ◽  
Author(s):  
Fred Levien ◽  
Paul Buczynski
Keyword(s):  
Field Test ◽  
Test Study

AEROMAGNETIC FIELD TEST OF TOTAL INTENSITY UPWARD CONTINUATION

Geophysics ◽  
1971 ◽  
Vol 36 (2) ◽  
pp. 418-425 ◽  
Author(s):  
Angelo L. Kontis
Keyword(s):  
Dirichlet Problem ◽  
Field Test ◽  
Theoretical Basis ◽  
Numerical Evaluation ◽  
Integral Formula ◽  
Intensity Data ◽  
Magnetic Intensity ◽  
Normal Field ◽  
Area Of Interest ◽  
Upward Continuation

The theoretical basis for applying the upward‐continuation integral, [Formula: see text]z⩽0, (1) to total magnetic intensity data T(α, β) measured on the plane z=0 has been recently reviewed by Henderson (1970). To perform upward continuation in the spatial domain, weights or coefficients obtained by numerical evaluation of equation (1) (Peters, 1949; Henderson, 1960; Fuller, 1967) may be convolved with the total intensity anomaly T(α, β) to produce T(x, y, z) at heights z<0 (for z positive downward). The accuracy of upward continuation is, therefore, dependent on the validity of the numerical coefficients and of the assumptions required to show that T(α, β) satisfies the conditions of the Dirichlet problem for a plane. These assumptions are that the quantity sensed by a total‐intensity magnetometer is in the direction of the earth’s normal field and that this direction is invariant over the area of interest.

Theoretical basis of research of personal mediation of manipuiative tendencies

2021 ◽  
Vol 2021 (2) ◽  
pp. 25-34
Author(s):  
Yu. V. Borets ◽  
◽  
O. V. Palahniuk ◽  
Keyword(s):  
Theoretical Analysis ◽  
Key Words ◽  
Theoretical Basis ◽  
Scientific Literature ◽  
Use Of Force ◽  
Training Process ◽  
The Will ◽  
The Subject ◽  
The Right ◽  
Practical Implications

The purpose of the article. Theoretical analysis of personal mediation of manipuiative tendencies. Methodology. The basis of this study is a theoretical analysis, synthesis, generalization, systematization of available scientific literature on the subject. Results. Manipulation of consciousness is one of the ways to dominate and suppress the will of people by acting on them through the programming of their behavior. This action is aimed at the mental structures of man, which is carried out secretly and aims to change the thoughts, motivations and goals of people in the right direction for a certain group of people. In this case, the purpose of manipulation – hiding their true intentions, to encourage another person to take certain actions, change values, ideas and opinions, etc., while maintaining the illusion of independence in general and independence of decisions or actions. In other words, to motivate a person to what he does not want to do, to distract from what he aspires to, but at the same time to create in him the confidence that he is acting of his own free will. Practical implications. The need to study manipulative tendencies is to determine the main ways and methods of manipulation and ways to protect against manipulative action. To reveal the main features of the manipulator’s personality and the category of people who are most prone to manipulative action. Theoretical materials can be used in the training process of the courses “Psychology of personality”, “Age Psychology”, “Differential Psychology”, “Fundamentals psychological correction”. Originality/value. It was found that the criteria for manipulation are: the attitude of the manipulator to the objects of manipulation as a means to achieve their own goal, the desire to gain unilateral advantage, the hidden nature of influence, use of force, motivation, motivation and skill in the process of manipulative influence. Key words: manipulation, coercion, manipulation, subject of manipulation, projection, Machiavellianism, manipulative influence.

scholarly journals Dual-Input Isolated DC-DC Converter with Ultra-High Step-Up Ability Based on Sheppard Taylor circuit

Electronics ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 1125 ◽  
Author(s):  
Shen ◽  
Chen ◽  
Chen
Keyword(s):  
Theoretical Analysis ◽  
Hardware Implementation ◽  
Lower Cost ◽  
Voltage Gain ◽  
Theoretical Derivation ◽  
Stage Design ◽  
Control Approach ◽  
Power Stage ◽  
Voltage Clamping ◽  
Switch Voltage

A dual-input high step-up isolated converter (DHSIC) is proposed in this paper, which incorporates Sheppard Taylor circuit into power stage design so as to step up voltage gain. In addition, the main circuit adopts boosting capacitors and switched capacitors, based on which the converter voltage gain can further be improved significantly. Since the proposed converter possesses an inherently ultra-high step-up feature, it is capable of processing low input voltages. The DHSIC also has the important features of leakage energy recycling, switch voltage clamping, and continuous input-current obtaining. These characteristics advantage converter efficiency and benefit the DHSIC for high power applications. The structure of the proposed converter is concise. That is, it can lower cost and simplifies control approach. The operation principle and theoretical derivation of the proposed converter are discussed thoroughly in this paper. Simulations and hardware implementation are carried out to verify the correctness of theoretical analysis and to validate feasibility of the converter as well.

Field Test Study on Treatment of Dredged Soil with Cotton Straw

2020 ◽  
Vol 57 (4) ◽  
pp. 343-350
Author(s):  
Xiaojuan Yu ◽  
Chao Liu ◽  
Fenglin Lu
Keyword(s):  
Field Test ◽  
Dredged Soil ◽  
Test Study

scholarly journals Mechanical Vibration Mechanism Motion Simulation of Ultrasonic Composite Vibration Polishing Equipment

2018 ◽  
Vol 237 ◽  
pp. 01014
Author(s):  
Wan Hongqiang ◽  
Han Peiying ◽  
Ge Shuai ◽  
Fancong Li ◽  
Zhang Simiao
Keyword(s):  
Theoretical Analysis ◽  
Theoretical Basis ◽  
Mechanical Vibration ◽  
Motion Simulation ◽  
Connecting Rod ◽  
Adams Software ◽  
Piston Mechanism ◽  
Working Principle ◽  
Vibration Mechanism ◽  
Ansys Workbench

In order to design a kind of mechanical vibration part with stable motion in ultrasonic composite vibration polishing equipment. firstly, the main working principle of ultrasonic composite vibration polishing equipment is briefly introduced. Secondly, the mechanical vibration structure of the design is analyzed theoretically, again, using ADAMS software to simulate the crankshaft connecting rod piston mechanism. When the crankshaft speed is 750r/min, the stroke of the piston is 90mm, which is similar to the theoretical analysis value. Finally, using ANSYS Workbench software to analyze the crankshaft statics. The analysis shows that the design of the mechanical vibration structure is reasonable, which provides a theoretical basis for the study of the mechanical vibration structure of ultrasonic composite vibration polishing equipment.

Comparative Study on Ultimate Pullout Resistance Test and Theoretical Derivation of Flexible Pressurized Anchor with Numerical Simulation Result

2012 ◽  
Vol 268-270 ◽  
pp. 753-760
Author(s):  
Xuan Li Zhang ◽  
Wen Bin Wei
Keyword(s):  
Numerical Simulation ◽  
Theoretical Analysis ◽  
Theoretical Derivation ◽  
Material Body ◽  
Pullout Resistance ◽  
Test Study ◽  
Simulation Calculation ◽  
Calculation Process ◽  
Calculation Results ◽  
Pressure Stress

The study on anchorage characteristics of flexible pressurized anchor should be along with theoretical analysis, numerical simulation and test study. Through comparing three calculation results, it is concluded that the theoretical analysis and numerical simulation can authenticate the correctness of calculation process each other; After considering the situation that friction coefficient changed with different contact pressure stress, the deviation of calculation of theory derivation and numerical simulation with experimental results significantly reduced; Anchor was simplified for anisotropic composite material body, which should be able to better reduce deviation among test, theoretical derivation and numerical simulation calculation.

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