In coal mine construction,to make the optimal plan of complete sets of equipment needs to set up a mixed integer nonlinear programming model,which has many variables and more complicated parameters to set.The problem...In coal mine construction,to make the optimal plan of complete sets of equipment needs to set up a mixed integer nonlinear programming model,which has many variables and more complicated parameters to set.The problem could hardly be solved using general methods.In this paper a new genetic approach—the hierarchical iterative genetic algorithm (HIGA) was designed to solve it and a satisfactory solution was obtained.展开更多
In view of failure phenomena with nonlinear large deformation including extensive damage,whole section destruction in short time,high rate of repair,most destruction forms occurred in the tertiary roadway of soft rock...In view of failure phenomena with nonlinear large deformation including extensive damage,whole section destruction in short time,high rate of repair,most destruction forms occurred in the tertiary roadway of soft rocks engineering in Liuhai mine,according to the methods of geological survey,theoretical analysis,numerical calculation and in-situ test,the composite failure mechanism of molecular expansion,tectonic stress,gravity stress and engineering deviatoric stress,faults and random joint in this area is analyzed deeply,then an coupling support of double-layer-truss is proposed.The research results show that the first wave of deformation energy was released by bolt-mesh-cable fixed into the roof,floor and two sides of the roadway.While the second wave of deformation energy was released through the interface function between double-layer-truss and the surrounding rock.The double-layer-truss that characterized by high strength,good integrity can absorb high deformation energy of surrounding rocks,which led to the uniform distribution of the stress.Engineering practice shows this technology has been successfully applied to control the deformation failure of the tertiary extremely soft rock roadway.展开更多
Founded in 1902 as the Transvaal Miners＇ Association, the South African Mine Workers＇ Union （MWU）, as it was renamed in 1913, rose to prominence as a militant union for white miners, especially during the turbulen...Founded in 1902 as the Transvaal Miners＇ Association, the South African Mine Workers＇ Union （MWU）, as it was renamed in 1913, rose to prominence as a militant union for white miners, especially during the turbulent years of industrial strife and bloody strike action in the first two decades of the 20th century. Since the election victory of the Pact government in 1924 a program of pro-white protectionist legislation was introduced. As South Africa＇s most prominent white trade union of the 20th century, the MWU therefore became renowned for defending job reservation in the mining industry. After 1948, it enjoyed the National Party government＇s support in this regard. However, skilled labor shortages and changing labor conditions in the 1970s forced the government to introduce labor reform. Job reservation was scrapped and black unions were officially recognized. These initiatives put the MWU on a confrontational path with the government and the union aligned itself with right-wing political resistance and protest. But, the altered political and economic South African realities after 1994 forced the MWU to rethink its strategies. By 2002, it had reinvented and transformed itself into Solidarity, adequately equipped for addressing the labor challenges and demands of a post-apartheid South Africa. This article, based on the author＇s research of the South African labor movement in the early 20th century, traces the historical development of the union and its influence on South African political and labor history.展开更多
文摘In coal mine construction,to make the optimal plan of complete sets of equipment needs to set up a mixed integer nonlinear programming model,which has many variables and more complicated parameters to set.The problem could hardly be solved using general methods.In this paper a new genetic approach—the hierarchical iterative genetic algorithm (HIGA) was designed to solve it and a satisfactory solution was obtained.
基金supported by program for the National Natural Science Foundation of China (No.51304210)the Specialized Research Foundation for the Doctoral Program of Higher Education by the Ministry of Education (No.20120023120014)
文摘In view of failure phenomena with nonlinear large deformation including extensive damage,whole section destruction in short time,high rate of repair,most destruction forms occurred in the tertiary roadway of soft rocks engineering in Liuhai mine,according to the methods of geological survey,theoretical analysis,numerical calculation and in-situ test,the composite failure mechanism of molecular expansion,tectonic stress,gravity stress and engineering deviatoric stress,faults and random joint in this area is analyzed deeply,then an coupling support of double-layer-truss is proposed.The research results show that the first wave of deformation energy was released by bolt-mesh-cable fixed into the roof,floor and two sides of the roadway.While the second wave of deformation energy was released through the interface function between double-layer-truss and the surrounding rock.The double-layer-truss that characterized by high strength,good integrity can absorb high deformation energy of surrounding rocks,which led to the uniform distribution of the stress.Engineering practice shows this technology has been successfully applied to control the deformation failure of the tertiary extremely soft rock roadway.
文摘Founded in 1902 as the Transvaal Miners＇ Association, the South African Mine Workers＇ Union （MWU）, as it was renamed in 1913, rose to prominence as a militant union for white miners, especially during the turbulent years of industrial strife and bloody strike action in the first two decades of the 20th century. Since the election victory of the Pact government in 1924 a program of pro-white protectionist legislation was introduced. As South Africa＇s most prominent white trade union of the 20th century, the MWU therefore became renowned for defending job reservation in the mining industry. After 1948, it enjoyed the National Party government＇s support in this regard. However, skilled labor shortages and changing labor conditions in the 1970s forced the government to introduce labor reform. Job reservation was scrapped and black unions were officially recognized. These initiatives put the MWU on a confrontational path with the government and the union aligned itself with right-wing political resistance and protest. But, the altered political and economic South African realities after 1994 forced the MWU to rethink its strategies. By 2002, it had reinvented and transformed itself into Solidarity, adequately equipped for addressing the labor challenges and demands of a post-apartheid South Africa. This article, based on the author＇s research of the South African labor movement in the early 20th century, traces the historical development of the union and its influence on South African political and labor history.
