Presented is design concept for key parameters o f the reverse conducting gate commutated thyristor (RC-GCT),such as the thickness and concentration of n-base region and the transparent anode region,and the wi dth o...Presented is design concept for key parameters o f the reverse conducting gate commutated thyristor (RC-GCT),such as the thickness and concentration of n-base region and the transparent anode region,and the wi dth of separation region between asymmetric GCT and PIN diode.A structure model of the RC-GCT is set up based on the design concept and its characteristics are analyzed.The simulation results show the design concept is reasonable.展开更多
In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining district.Three reasons are proposed:de...In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining district.Three reasons are proposed:deep high stress,improper roadway layout and support technology.The stability control countermeasures of the gate group consist of an intensive design technology and responding bolt-mesh-anchor truss support technology.Our research method has been applied at the -1000 m level gate group in Qishan Coal Mine.Suitable countermeasures have been tested by field monitoring.展开更多
A comprehensive investigation was performed for repairing the different types of cracks appearing on the surface or inside the concrete lining at various depths.The mate- rial properties used in grouting and two metho...A comprehensive investigation was performed for repairing the different types of cracks appearing on the surface or inside the concrete lining at various depths.The mate- rial properties used in grouting and two methods for crack repair were discussed in details, and consequently reliable repair measures were proposed and implemented.It is a better choice to adopt the hole-drilling method for the relatively regular crack.The grouting pres- sure should not be too high and it is generally between 0.4～0.6 MPa.For the second time grouting,the pressure maybe increased to 0.8 MPa.Other method is the pasting nozzles method which is more suitable for irregular cracks such as cracks with intensive density and crossing cracks.Its grouting pressure is generally between 0.6～1.0 MPa.The in-situ tests in Three Gorges Project demonstrate favorably the feasibility and applicability of the proposed methods for crack repair within the lining concrete.展开更多
文摘Presented is design concept for key parameters o f the reverse conducting gate commutated thyristor (RC-GCT),such as the thickness and concentration of n-base region and the transparent anode region,and the wi dth of separation region between asymmetric GCT and PIN diode.A structure model of the RC-GCT is set up based on the design concept and its characteristics are analyzed.The simulation results show the design concept is reasonable.
基金Projects 50490270 supported by the National Natural Science Foundation of ChinaProjects 2006CB202200 by the National Basic Research Program of ChinaProjects IRT0656 by the Innovation Term Project of the Ministry of Education of China
文摘In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining district.Three reasons are proposed:deep high stress,improper roadway layout and support technology.The stability control countermeasures of the gate group consist of an intensive design technology and responding bolt-mesh-anchor truss support technology.Our research method has been applied at the -1000 m level gate group in Qishan Coal Mine.Suitable countermeasures have been tested by field monitoring.
基金the National Natural Science Foundation of China(10602049)
文摘A comprehensive investigation was performed for repairing the different types of cracks appearing on the surface or inside the concrete lining at various depths.The mate- rial properties used in grouting and two methods for crack repair were discussed in details, and consequently reliable repair measures were proposed and implemented.It is a better choice to adopt the hole-drilling method for the relatively regular crack.The grouting pres- sure should not be too high and it is generally between 0.4～0.6 MPa.For the second time grouting,the pressure maybe increased to 0.8 MPa.Other method is the pasting nozzles method which is more suitable for irregular cracks such as cracks with intensive density and crossing cracks.Its grouting pressure is generally between 0.6～1.0 MPa.The in-situ tests in Three Gorges Project demonstrate favorably the feasibility and applicability of the proposed methods for crack repair within the lining concrete.
