Forecast is very important for preventing and controlling the disaster of spontaneous combustion （sponcom）. Gaseous products of coal, such as carbon monoxide, ethylene, propane and hydrogen, are commonly used as ind...Forecast is very important for preventing and controlling the disaster of spontaneous combustion （sponcom）. Gaseous products of coal, such as carbon monoxide, ethylene, propane and hydrogen, are commonly used as indicators to reflect its status quo of sponcom in coal mines. Nevertheless, since the corresponding relationship between the temperature and the indicators is non-linear and can＇t be depicted with simple mathematical formula, it is very difficult to diagnose and forecast coal sponcom by monitoring indicator gases＇ distribution. A forward feeding 3-layer artificial neural network （ANN） model is employed to express the corresponding relation between temperature and index gases of coal sponcom more accurately. A large amount of data from programmed temperature oxidation experiments were employed to train the network to gain the connection strength between nerve cells and to accomplish the model. It proved in real coal productions that the ANN model can forecast coal sponcom accurately.展开更多
In order to observe CO_2 characteristics in the unsaturated zone of loess tableland and further understand the carbon cycle,a series of tubes for gas monitoring and sampling were installed in an approximately 90-m dee...In order to observe CO_2 characteristics in the unsaturated zone of loess tableland and further understand the carbon cycle,a series of tubes for gas monitoring and sampling were installed in an approximately 90-m deep Qiushe loess section of Lingtai County,Northwestern China.The results show that the concentration of CO_2 was higher in loess than in the atmosphere,reaching a maximum of 6970 lmol·mol^(-1).CO_2 concentrations in loess were higher in summer than in winter.The CO_2 in loess was related to organic carbon decomposed by microbes,and to the CaCO_3–H_2O–CO_2 system in the interface between the saturated and unsaturated zones.展开更多
Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Proph...Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Prophet Mosque in Al-Madinah A l-Munawarah from early 12：00 to 14：00 of Friday and from 19：00 to 22：30 at holy month, Ramadan. The percentage of both carbon monoxide （CO） and nitrogen dioxide （NO2） had significantly increased （p 〈 0.05-0.005）. The peak levels of these air pollutants were between 13：15-13：20 during Fridays. The increase in the emission of these exhausted gases was concomitant with the significant decrease （p 〈 0.05） in oxygen （02） levels but the latter recovered its levels after 13：20 hours. The arithmetic total mean density of vehicle per minute （vpm） at Salam Road, the busiest road of Al-Madinah, during hours （07：00-09：00）, （13：00-15：00） and （17：00-19：00） of both Friday and Saturdays respectively were （8/45, 16/40 and 36/43）. The increase in air pollution has been attributed to a dramatic increase in number of public cars use the car parks during these times, the consequent congestion at entries, the excess or/and poor consumption of fuels being utilized and the inadequate ventilation.展开更多
The monitor is composed of a pair of electrodes,a single stage of microchannel plate,a phosphor screen,a CCD camera and a PC computer,To obtain a good uniform collecting field,forming electrodes system is used instead...The monitor is composed of a pair of electrodes,a single stage of microchannel plate,a phosphor screen,a CCD camera and a PC computer,To obtain a good uniform collecting field,forming electrodes system is used instead of that with a resistive divider,The readout system is performed by the phosphor screen and the CCD camera because the spatial resolution is not limited by the mechanical structure like the anode strip type and such video display system is very useful for beam studies and operation of the 40MeV linac,Besides,the design and test results are described in detail.展开更多
Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics o...Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics of gas migration in working face airflow direction are qualitatively analyzed. The calculation method of asynchronous correlation delay step and the prediction and inversion formulas of gas concentration changing with time and space after gas emission in the air return roadway are provided. By calculating one hundred and fifty groups of gas sensors data series from a coal mine which have the theoretical correlativity, the correlative coefficient values range of eight kinds of data anomaly is obtained. Then the gas moni- toring data anomaly identification algorithm based on spatio-temporal correlativity analysis is accordingly presented. In order to improve the efficiency of analysis, the gas sensors code rules which can express the spatial topological relations are sug- gested. The experiments indicate that methods presented in this article can effectively compensate the defects of methods based on a single gas sensor monitoring data.展开更多
Described the main environmental hazards occurring in Polish undergroundmines and their continuous growth in recent years as well as equipment and systemswhich were used for monitoring mine air parameters and geodynam...Described the main environmental hazards occurring in Polish undergroundmines and their continuous growth in recent years as well as equipment and systemswhich were used for monitoring mine air parameters and geodynamic phenomena.Thelatest versions of environmental hazard monitoring systems,having a form of a comprehensiveset of underground and surface equipment,are presented and their functionscharacterized.展开更多
基金Supported by the National Natural Science Foundation of China （10972178）
文摘Forecast is very important for preventing and controlling the disaster of spontaneous combustion （sponcom）. Gaseous products of coal, such as carbon monoxide, ethylene, propane and hydrogen, are commonly used as indicators to reflect its status quo of sponcom in coal mines. Nevertheless, since the corresponding relationship between the temperature and the indicators is non-linear and can＇t be depicted with simple mathematical formula, it is very difficult to diagnose and forecast coal sponcom by monitoring indicator gases＇ distribution. A forward feeding 3-layer artificial neural network （ANN） model is employed to express the corresponding relation between temperature and index gases of coal sponcom more accurately. A large amount of data from programmed temperature oxidation experiments were employed to train the network to gain the connection strength between nerve cells and to accomplish the model. It proved in real coal productions that the ANN model can forecast coal sponcom accurately.
基金supported jointly by National Natural Science Foundation of China(41403107,41325010)the Basic Science Research Fund from the Institute of Hydrogeology and Environmental Geology(SK201208)and the China Geological Survey Projects(12120113005900)
文摘In order to observe CO_2 characteristics in the unsaturated zone of loess tableland and further understand the carbon cycle,a series of tubes for gas monitoring and sampling were installed in an approximately 90-m deep Qiushe loess section of Lingtai County,Northwestern China.The results show that the concentration of CO_2 was higher in loess than in the atmosphere,reaching a maximum of 6970 lmol·mol^(-1).CO_2 concentrations in loess were higher in summer than in winter.The CO_2 in loess was related to organic carbon decomposed by microbes,and to the CaCO_3–H_2O–CO_2 system in the interface between the saturated and unsaturated zones.
文摘Using air pollution detecting equipments ITX, ATX620 and IBRID-MX6 Multi gas monitors a pioneer research was carried out to assess the levels of the exhausted gas emission in double-floored car parks of the Holy Prophet Mosque in Al-Madinah A l-Munawarah from early 12：00 to 14：00 of Friday and from 19：00 to 22：30 at holy month, Ramadan. The percentage of both carbon monoxide （CO） and nitrogen dioxide （NO2） had significantly increased （p 〈 0.05-0.005）. The peak levels of these air pollutants were between 13：15-13：20 during Fridays. The increase in the emission of these exhausted gases was concomitant with the significant decrease （p 〈 0.05） in oxygen （02） levels but the latter recovered its levels after 13：20 hours. The arithmetic total mean density of vehicle per minute （vpm） at Salam Road, the busiest road of Al-Madinah, during hours （07：00-09：00）, （13：00-15：00） and （17：00-19：00） of both Friday and Saturdays respectively were （8/45, 16/40 and 36/43）. The increase in air pollution has been attributed to a dramatic increase in number of public cars use the car parks during these times, the consequent congestion at entries, the excess or/and poor consumption of fuels being utilized and the inadequate ventilation.
文摘The monitor is composed of a pair of electrodes,a single stage of microchannel plate,a phosphor screen,a CCD camera and a PC computer,To obtain a good uniform collecting field,forming electrodes system is used instead of that with a resistive divider,The readout system is performed by the phosphor screen and the CCD camera because the spatial resolution is not limited by the mechanical structure like the anode strip type and such video display system is very useful for beam studies and operation of the 40MeV linac,Besides,the design and test results are described in detail.
基金Supported by the National Natural Science Foundation of China （40971275, 50811120111）
文摘Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics of gas migration in working face airflow direction are qualitatively analyzed. The calculation method of asynchronous correlation delay step and the prediction and inversion formulas of gas concentration changing with time and space after gas emission in the air return roadway are provided. By calculating one hundred and fifty groups of gas sensors data series from a coal mine which have the theoretical correlativity, the correlative coefficient values range of eight kinds of data anomaly is obtained. Then the gas moni- toring data anomaly identification algorithm based on spatio-temporal correlativity analysis is accordingly presented. In order to improve the efficiency of analysis, the gas sensors code rules which can express the spatial topological relations are sug- gested. The experiments indicate that methods presented in this article can effectively compensate the defects of methods based on a single gas sensor monitoring data.
文摘Described the main environmental hazards occurring in Polish undergroundmines and their continuous growth in recent years as well as equipment and systemswhich were used for monitoring mine air parameters and geodynamic phenomena.Thelatest versions of environmental hazard monitoring systems,having a form of a comprehensiveset of underground and surface equipment,are presented and their functionscharacterized.
