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Start Over Coverage 169-182

1. "Z krvácejících rakví teče naše vůle." Sudetští Němci také jako muži října?

Creator:
Petrbok, Václav and Randák, Jan
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
March 4th 1919, October 28th 1918, Czechoslovakia, Sudeten, Czech Germans, and self-determination
Language:
Czech
Description:
The study situates the events that took place on the Czech borderland on March 4th, 1919 into a greater historical context and refers to the usage of the imagery of the fallen Czech German protestors in contemporary literature. and Článek zahrnuje poznámkový aparát pod čarou
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Numerical insights into stress redistribution in protected seam mining with coal pillars and an application to methane control

Creator:
He , Fulian, Zhu , Ruojun, and Zhu , Hengzhong
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
protected seam mining, coal pillar, stress redistribution, methane control, and divisional management strategy
Language:
English
Description:
This paper identifies the stress redistribution of protected seams under the influence of coal pillars and a divisional management strategy for methane control. A coal pillar that is reserved in the protective seam greatly affects the abutment stress, the O-shaped circle’s evolution and the stress distribution. The strain-soften model was conducted using FLAC3D numerical analysis software to investigate the stress redistribution in the protected seam mining process. The results show that the abutment stress reaches a maximum value of 1.25 times the original stress when a protected seam coal face lies in the center of the coal pillar’s affected zone. The O-shaped circle is divided into two parts by the coal pillar, and its developmental width is closely associated with the protected seam mining stage and the developmental height of the “three zones”, especially the fractured zone. The stress redistribution of protected seam is rarely affected by the coal pillar when the distance is greater than 26 m. Both the total increased stress belt of the coal pillar affected zone and the total decreased stress belt of the other zones along the vertical direction significantly influence the methane migration. We propose a divisional management strategy that supplies a theoretical basis and technical guidance for methane control.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3. Oscillation properties for a scalar linear difference equation of mixed type

Creator:
Berezansky, Leonid and Pinelas, Sandra
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
oscillation, difference equation, mixed type, and asymptotic behavior
Language:
English
Description:
The aim of this work is to study oscillation properties for a scalar linear difference equation of mixed type ∆x(n) + ∑ q k=−p ak(n)x(n + k) = 0, n > n0, where ∆x(n) = x(n + 1) − x(n) is the difference operator and {ak(n)} are sequences of real numbers for k = −p, . . . , q, and p > 0, q > 0. We obtain sufficient conditions for the existence of oscillatory and nonoscillatory solutions. Some asymptotic properties are introduced.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public