In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating t...In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating the geologically horizontal strata. We carried out physical modeling on the deformation and failure processes of roadways subjected to a plane loading scheme. Our laboratory tests were based on work which incorporated infrared (IR) detection, IR radiation temperature (IRT) statistics, image feature extraction and 2D Fourier transformation, from resulting thermographies. The IRT characterizes the mechanical responses from the roadway after loading with two stages, i.e., IRT evolving at higher levels corresponded to shallow mining (≤500 m) during which the roadway deformed gradually (referred to as the "steady deformation stage"); IRT evolving in a quasi-cyclical manner with multiple peaks corresponded to deep mining (800–2600 m), in which the failure mode for the roadway are dominated by breakage and collapse (called the "unsteady deformation stage"). The IR images and 2D Fourier spectra illustrate detailed information in terms of initiation, nucleation and coalescence of the damage to rock masses and the eventual failure of roadways subject to external loading.展开更多
Hungary＇s accession to the European Union in 2004 marked the start of a new era. The completion of legal harmonization brought in new emission standards and thresholds, and this was followed by EU-assisted projects t...Hungary＇s accession to the European Union in 2004 marked the start of a new era. The completion of legal harmonization brought in new emission standards and thresholds, and this was followed by EU-assisted projects to build and reconstruct wastewater treatment plants. The utilization of sludge after it leaves the wastewater treatment plant is now a solely private-sector operation. There are new political priorities： increasing state involvement, buying out of major--formerly privatized--service providers, reintegration of isolated service providers, legally-imposed reduction of public utility charges. As a result, a demand has arisen for a greater central, i.e. government role in sludge utilization.展开更多
基金Projects 2006CB202200 supported by the Special Funds for the Major State Basic Research ProjectIRT0656 by the Innovative Team Development Project of the State Educational Ministry of China
文摘In order to capture the mechanism of roadway instability in deep mines, a new approach of Physically Finite Elemental Slab Assemblage (PFESA) is proposed in order to construct a large-scale physical model simulating the geologically horizontal strata. We carried out physical modeling on the deformation and failure processes of roadways subjected to a plane loading scheme. Our laboratory tests were based on work which incorporated infrared (IR) detection, IR radiation temperature (IRT) statistics, image feature extraction and 2D Fourier transformation, from resulting thermographies. The IRT characterizes the mechanical responses from the roadway after loading with two stages, i.e., IRT evolving at higher levels corresponded to shallow mining (≤500 m) during which the roadway deformed gradually (referred to as the "steady deformation stage"); IRT evolving in a quasi-cyclical manner with multiple peaks corresponded to deep mining (800–2600 m), in which the failure mode for the roadway are dominated by breakage and collapse (called the "unsteady deformation stage"). The IR images and 2D Fourier spectra illustrate detailed information in terms of initiation, nucleation and coalescence of the damage to rock masses and the eventual failure of roadways subject to external loading.
文摘Hungary＇s accession to the European Union in 2004 marked the start of a new era. The completion of legal harmonization brought in new emission standards and thresholds, and this was followed by EU-assisted projects to build and reconstruct wastewater treatment plants. The utilization of sludge after it leaves the wastewater treatment plant is now a solely private-sector operation. There are new political priorities： increasing state involvement, buying out of major--formerly privatized--service providers, reintegration of isolated service providers, legally-imposed reduction of public utility charges. As a result, a demand has arisen for a greater central, i.e. government role in sludge utilization.
