The simulation performance over complex building clusters of a wind simulation model(Wind Information Field Fast Analysis model, WIFFA) in a micro-scale air pollutant dispersion model system(Urban Microscale Air Po...The simulation performance over complex building clusters of a wind simulation model(Wind Information Field Fast Analysis model, WIFFA) in a micro-scale air pollutant dispersion model system(Urban Microscale Air Pollution dispersion Simulation model, UMAPS) is evaluated using various wind tunnel experimental data including the CEDVAL(Compilation of Experimental Data for Validation of Micro-Scale Dispersion Models) wind tunnel experiment data and the NJU-FZ experiment data(Nanjing University-Fang Zhuang neighborhood wind tunnel experiment data). The results show that the wind model can reproduce the vortexes triggered by urban buildings well, and the flow patterns in urban street canyons and building clusters can also be represented. Due to the complex shapes of buildings and their distributions, the simulation deviations/discrepancies from the measurements are usually caused by the simplification of the building shapes and the determination of the key zone sizes. The computational efficiencies of different cases are also discussed in this paper. The model has a high computational efficiency compared to traditional numerical models that solve the Navier–Stokes equations, and can produce very high-resolution(1–5 m) wind fields of a complex neighborhood scale urban building canopy(~ 1 km ×1km) in less than 3 min when run on a personal computer.展开更多
In the water modeling experiments, three cases were considered, i. e, , a bare tundish, a tundish equipped with a turbulence inhibitor, and a rectangular tundish equipped with weirs (dams) and a turbulence inhibitor...In the water modeling experiments, three cases were considered, i. e, , a bare tundish, a tundish equipped with a turbulence inhibitor, and a rectangular tundish equipped with weirs (dams) and a turbulence inhibitor. Comparing the RTD curves, inclusion separation, and the result of the streamline experiment, it can be found that the tundish equipped with weirs (dams) and a turbulence inhibitor has a great effect on the flow field and the inclusion separation when compared with the sole use or no use of the turbulent inhibitor or weirs (dams). In addition, the enlargement of the distance between the weir and dam will result in a better effect when the tundish equipped with weirs (dam) and a turbulence inhibitor was used.展开更多
A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment (GRACE) K-Band Range Rate (KBRR) data based on dynamic integral approach is presented in this pa...A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment (GRACE) K-Band Range Rate (KBRR) data based on dynamic integral approach is presented in this paper. After meticulously preprocessing of the GRACE KBRR data, the root mean square of its post residuals is about 0.2 micrometers per second, and seventy-two monthly temporal solutions truncated to degree and order 60 are computed for the period from January 2003 to December 2008. After applying the combi- nation filter in WHU-Grace01s, the global temporal signals show obvious periodical change rules in the large-scale fiver basins. In terms of the degree variance, our solution is smaller at high degrees, and shows a good consistency at the rest of degrees with the Release 05 models from Center for Space Research (CSR), GeoForschungsZentrum Potsdam (GFZ) and Jet Pro- pulsion Laboratory 0PL). Compared with other published models in terms of equivalent water height distribution, our solution is consistent with those published by CSR, GFZ, JPL, Delft institute of Earth Observation and Space system (DEOS), Tongji University (Tongji), Institute of Theoretical Geodesy (ITG), Astronomical Institute in University of Bern (AIUB) and Groupe de Recherche de Geodesie Spatiale (GRGS}, which indicates that the accuracy of WHU-Grace01s has a good consistency with the previously published GRACE solutions.展开更多
Tbe experimental simulation has been performed to investigate the smoke flowing properties within the 1/5 reduced-scale model of a sleeping carriage. The velocity field of the running train on fire is simulated in a w...Tbe experimental simulation has been performed to investigate the smoke flowing properties within the 1/5 reduced-scale model of a sleeping carriage. The velocity field of the running train on fire is simulated in a wind tunnel of the State Key Lab of Fire Science, USTC (University of Science & Technology of China). In this paper, the fire-smoking properties and the variation of the temperature field in the sleeping carriage are analyzed. This paper introduces the simulation method of reducedscale experiment about the running train and the analysis or the experimental data. It provides the basis of experiment for the running train’s fire-safety and full-scale experiment in the future study.展开更多
Interwell connectivities are fundamental parameters required to manage waterfloods in oil reservoirs. Data-driven models, such as the capacitance-resistance model (CRM), are fast tools to estimate these parameters f...Interwell connectivities are fundamental parameters required to manage waterfloods in oil reservoirs. Data-driven models, such as the capacitance-resistance model (CRM), are fast tools to estimate these parameters from time-correlations of input (injection rates) and output (production rates) signals. Noise and structure of the input time-series impose limits on the information that can be extracted from a given data-set. This work uses the CRM to study general prescriptions for the design of input signals that enhance the information content of injection/production data in the estimation of well-to-well interactions. Numerical schemes and general features of the optimal input signal strategy are derived for this problem.展开更多
The development of analysis on train-induced ground vibration is briefly summarized. A train-track- ground integrated dynamic model is introduced in the paper to predict the ground vibration induced by high-speed trai...The development of analysis on train-induced ground vibration is briefly summarized. A train-track- ground integrated dynamic model is introduced in the paper to predict the ground vibration induced by high-speed trains. Representative dynamic responses of the train-track-ground system predicted by the model are presented. Some major results measured from two field tests on the ground vibration induced by two high-speed trains are reported. Numerical prediction with the proposed train-track-ground model is validated by the high-speed train running experiments. Research results show that the wheel/rail dynamic interaction caused by track irregularities has a significant influence on the ground acceleration and little influence on the ground displacement. The main frequencies of the ground vibration induced by high-speed trains are usually below 80 Hz. Compared with the ballasted track, the ballastless track structure can produce much larger train-induced ground vibration at frequencies above 40 Hz. The vertical ground vibration is much larger than the lateral and longitudinal components.展开更多
In this paper we present a series of monthly gravity field solutions from Gravity Recovery and Climate Experiment(GRACE) range measurements using modified short arc approach,in which the ambiguity of range measureme...In this paper we present a series of monthly gravity field solutions from Gravity Recovery and Climate Experiment(GRACE) range measurements using modified short arc approach,in which the ambiguity of range measurements is eliminated via differentiating two adjacent range measurements.The data used for developing our monthly gravity field model are same as Tongji-GRACEOl model except that the range measurements are used to replace the range rate measurements,and our model is truncated to degree and order 60,spanning Jan.2004 to Dec.2010 also same as Tongji-GRACE01 model.Based on the comparison results of the C_(2,0),C_(2,1),S_(2,1),and C_(15,15),S_(15,15),time series and the global mass change signals as well as the mass change time series in Amazon area of our model with those of Tongji-GRACE01 model,we can conclude that our monthly gravity field model is comparable with Tongji-GRACE01 monthly model.展开更多
The overburden failure causes the changes of the constant electric field, and the resistivity is the main parameter in these changes. The experimental simulation about tbe response relation between the overburden fail...The overburden failure causes the changes of the constant electric field, and the resistivity is the main parameter in these changes. The experimental simulation about tbe response relation between the overburden failure and its electrical parameter changes is made by building the similar material physics model of mining. The experiment results are used to analyze and test the in-situ detection. The research indicates that the resistivity changes with the electric characteristic of the rock in cracked zone and caving zone caused by overburden failure, the response characteristics of resistivity vary with the failure degrees at different overburden failure zone and that they are corresponding. The resistivity method used in monitoring the overburden failure can determine the height and the affecting scopes of the cracked zone and caving zone. This can provide reliable techaological guarantee for mining design and safe production.展开更多
The Gravity Recovery and Climate Experiment(GRACE) mission can significantly improve our knowledge of the temporal variability of the Earth's gravity field.We obtained monthly gravity field solutions based on varia...The Gravity Recovery and Climate Experiment(GRACE) mission can significantly improve our knowledge of the temporal variability of the Earth's gravity field.We obtained monthly gravity field solutions based on variational equations approach from GPS-derived positions of GRACE satellites and K-band range-rate measurements.The impact of different fixed data weighting ratios in temporal gravity field recovery while combining the two types of data was investigated for the purpose of deriving the best combined solution.The monthly gravity field solution obtained through above procedures was named as the Institute of Geodesy and Geophysics(IGG) temporal gravity field models.IGG temporal gravity field models were compared with GRACE Release05(RL05) products in following aspects:(i) the trend of the mass anomaly in China and its nearby regions within 2005-2010; (ii) the root mean squares of the global mass anomaly during 2005-2010; (iii) time-series changes in the mean water storage in the region of the Amazon Basin and the Sahara Desert between 2005 and 2010.The results showed that IGG solutions were almost consistent with GRACE RL05 products in above aspects(i)-(iii).Changes in the annual amplitude of mean water storage in the Amazon Basin were 14.7 ± 1.2 cm for IGG,17.1 ± 1.3 cm for the Centre for Space Research(CSR),16.4 ± 0.9 cm for the GeoForschungsZentrum(GFZ) and 16.9 ± 1.2 cm for the Jet Propulsion Laboratory(JPL) in terms of equivalent water height(EWH),respectively.The root mean squares of the mean mass anomaly in Sahara were 1.2 cm,0.9 cm,0.9 cm and 1.2 cm for temporal gravity field models of IGG,CSR,GFZ and JPL,respectively.Comparison suggested that IGG temporal gravity field solutions were at the same accuracy level with the latest temporal gravity field solutions published by CSR,GFZ and JPL.展开更多
Based on the principle of similarity, water was used to simulate the flow of molten steel to analyze the flow field in a tundish. Several schemes of the tundish' s tracer shape were designed and corresponding water m...Based on the principle of similarity, water was used to simulate the flow of molten steel to analyze the flow field in a tundish. Several schemes of the tundish' s tracer shape were designed and corresponding water model experiments were conducted. During the experiments, a computer automatically collected data. The comparison of the residence time distribution( RTD ) curves drawn according to the computer-collected data optimized the scheme and photographs originated from the experiments with ink as its tracer. It indicates that the water model can optimize the flow field of the tundish.展开更多
[Objectives]To explore the antidepressant effect of Shenwei Ningyu Tablet,a new antidepressant traditional Chinese medicine,on rat chronic stress depression model and mouse tail suspension models.[Methods]Rat chronic ...[Objectives]To explore the antidepressant effect of Shenwei Ningyu Tablet,a new antidepressant traditional Chinese medicine,on rat chronic stress depression model and mouse tail suspension models.[Methods]Rat chronic stress model:except for the normal group,the rats in other groups were given corresponding chronic stress,and administered by gavage 1 h before modeling,for a total of 21 d.The changes of each indicator before and after the experiment were observed through the body weight change,the sugar water test,and open field test.The relevant hormone levels were detected by radioimmunoassay.Mouse tail suspension depression model:after continuous administration for 7 d,the activity times was recorded with the mouse automatic recorder,and the mouse immobility time was recorded after tail suspension,to explore the effects of each administration group on the tail suspension immobility time of mice.[Results]Chronic stress depression model:21 d after modeling,compared with the normal group,rats in the model group exhibited significantly reduced body weight,sucrose preference index,and horizontal and vertical movement scores(P<0.05).Compared with the model group,the low-dose Shenwei Ningyu Tablets group had significant differences in the sugar water test,horizontal and vertical movement scores(P<0.05).In addition,all three dose groups of Shenwei Ningyu Tablets could effectively reduce the content of CRF in chronic stress model rats,and the low dose group could significantly reduce the ACTH level in model rats(P<0.05).Mouse tail suspension depression model:the immobility time after tail suspension in each administration group was significantly different from that in the model group(P<0.05).[Conclusions]Shenwei Ningyu Tablets has a certain anti-depression effect on both the rat chronic stress depression model and the mouse tail suspension depression model.展开更多
基金supported by the China Special Fund for Meteorological Research in the Public Interest(Grant No.GYHY201106049)the National Natural Science Foundation of China(Grant Nos.51538005 and 41375014)the Jiangsu Collaborative Innovation Center for Climate Change,China
文摘The simulation performance over complex building clusters of a wind simulation model(Wind Information Field Fast Analysis model, WIFFA) in a micro-scale air pollutant dispersion model system(Urban Microscale Air Pollution dispersion Simulation model, UMAPS) is evaluated using various wind tunnel experimental data including the CEDVAL(Compilation of Experimental Data for Validation of Micro-Scale Dispersion Models) wind tunnel experiment data and the NJU-FZ experiment data(Nanjing University-Fang Zhuang neighborhood wind tunnel experiment data). The results show that the wind model can reproduce the vortexes triggered by urban buildings well, and the flow patterns in urban street canyons and building clusters can also be represented. Due to the complex shapes of buildings and their distributions, the simulation deviations/discrepancies from the measurements are usually caused by the simplification of the building shapes and the determination of the key zone sizes. The computational efficiencies of different cases are also discussed in this paper. The model has a high computational efficiency compared to traditional numerical models that solve the Navier–Stokes equations, and can produce very high-resolution(1–5 m) wind fields of a complex neighborhood scale urban building canopy(~ 1 km ×1km) in less than 3 min when run on a personal computer.
文摘In the water modeling experiments, three cases were considered, i. e, , a bare tundish, a tundish equipped with a turbulence inhibitor, and a rectangular tundish equipped with weirs (dams) and a turbulence inhibitor. Comparing the RTD curves, inclusion separation, and the result of the streamline experiment, it can be found that the tundish equipped with weirs (dams) and a turbulence inhibitor has a great effect on the flow field and the inclusion separation when compared with the sole use or no use of the turbulent inhibitor or weirs (dams). In addition, the enlargement of the distance between the weir and dam will result in a better effect when the tundish equipped with weirs (dam) and a turbulence inhibitor was used.
基金supported by the National 973Program of China(2013CB733302)the National Natural Science Foundation of China(41131067,41174020,41374023,41474019)+2 种基金the Open Research Fund Program of the State Key Laboratory of Geodesy and Earth's Dynamics(SKLGED2015-1-3-E)the open fund of State Key Laboratory of Geographic Information Engineering(SKLGIE2013-M-1-3)the open fund of Key Laboratory of Geospace Environment and Geodesy,Ministry of Education(13-02-05)
文摘A new temporal gravity field model called WHU-Grace01s solely recovered from Gravity Recovery and Climate Experiment (GRACE) K-Band Range Rate (KBRR) data based on dynamic integral approach is presented in this paper. After meticulously preprocessing of the GRACE KBRR data, the root mean square of its post residuals is about 0.2 micrometers per second, and seventy-two monthly temporal solutions truncated to degree and order 60 are computed for the period from January 2003 to December 2008. After applying the combi- nation filter in WHU-Grace01s, the global temporal signals show obvious periodical change rules in the large-scale fiver basins. In terms of the degree variance, our solution is smaller at high degrees, and shows a good consistency at the rest of degrees with the Release 05 models from Center for Space Research (CSR), GeoForschungsZentrum Potsdam (GFZ) and Jet Pro- pulsion Laboratory 0PL). Compared with other published models in terms of equivalent water height distribution, our solution is consistent with those published by CSR, GFZ, JPL, Delft institute of Earth Observation and Space system (DEOS), Tongji University (Tongji), Institute of Theoretical Geodesy (ITG), Astronomical Institute in University of Bern (AIUB) and Groupe de Recherche de Geodesie Spatiale (GRGS}, which indicates that the accuracy of WHU-Grace01s has a good consistency with the previously published GRACE solutions.
文摘Tbe experimental simulation has been performed to investigate the smoke flowing properties within the 1/5 reduced-scale model of a sleeping carriage. The velocity field of the running train on fire is simulated in a wind tunnel of the State Key Lab of Fire Science, USTC (University of Science & Technology of China). In this paper, the fire-smoking properties and the variation of the temperature field in the sleeping carriage are analyzed. This paper introduces the simulation method of reducedscale experiment about the running train and the analysis or the experimental data. It provides the basis of experiment for the running train’s fire-safety and full-scale experiment in the future study.
基金financial support and to the Center for Petroleum Asset Risk Management of the University of Texas at Austin for hospitality and an exciting research environment
文摘Interwell connectivities are fundamental parameters required to manage waterfloods in oil reservoirs. Data-driven models, such as the capacitance-resistance model (CRM), are fast tools to estimate these parameters from time-correlations of input (injection rates) and output (production rates) signals. Noise and structure of the input time-series impose limits on the information that can be extracted from a given data-set. This work uses the CRM to study general prescriptions for the design of input signals that enhance the information content of injection/production data in the estimation of well-to-well interactions. Numerical schemes and general features of the optimal input signal strategy are derived for this problem.
基金National Natural Science Foundation of China Under Grant No. 50838006 and No. 50823004the Traction Power State Key Laboratory of Southwest Jiaotong University Under Grant No. 2008TPL-Z05the Science and Technology Department of Sichuan Province
文摘The development of analysis on train-induced ground vibration is briefly summarized. A train-track- ground integrated dynamic model is introduced in the paper to predict the ground vibration induced by high-speed trains. Representative dynamic responses of the train-track-ground system predicted by the model are presented. Some major results measured from two field tests on the ground vibration induced by two high-speed trains are reported. Numerical prediction with the proposed train-track-ground model is validated by the high-speed train running experiments. Research results show that the wheel/rail dynamic interaction caused by track irregularities has a significant influence on the ground acceleration and little influence on the ground displacement. The main frequencies of the ground vibration induced by high-speed trains are usually below 80 Hz. Compared with the ballasted track, the ballastless track structure can produce much larger train-induced ground vibration at frequencies above 40 Hz. The vertical ground vibration is much larger than the lateral and longitudinal components.
基金sponsored by National Natural Science Foundation of China(41474017)National Key Basic Research Program of China(973 Program+3 种基金2012CB957703)sponsored by National Natural Science Foundation of China(41274035)State Key Laboratory of Geodesy and Earth's Dynamics(SKLGED2013-3-2-Z,SKLGED2014-1-3-E)State Key Laboratory of Geo-Information Engineering(SKLGIE2014-M-1-2)
文摘In this paper we present a series of monthly gravity field solutions from Gravity Recovery and Climate Experiment(GRACE) range measurements using modified short arc approach,in which the ambiguity of range measurements is eliminated via differentiating two adjacent range measurements.The data used for developing our monthly gravity field model are same as Tongji-GRACEOl model except that the range measurements are used to replace the range rate measurements,and our model is truncated to degree and order 60,spanning Jan.2004 to Dec.2010 also same as Tongji-GRACE01 model.Based on the comparison results of the C_(2,0),C_(2,1),S_(2,1),and C_(15,15),S_(15,15),time series and the global mass change signals as well as the mass change time series in Amazon area of our model with those of Tongji-GRACE01 model,we can conclude that our monthly gravity field model is comparable with Tongji-GRACE01 monthly model.
文摘The overburden failure causes the changes of the constant electric field, and the resistivity is the main parameter in these changes. The experimental simulation about tbe response relation between the overburden failure and its electrical parameter changes is made by building the similar material physics model of mining. The experiment results are used to analyze and test the in-situ detection. The research indicates that the resistivity changes with the electric characteristic of the rock in cracked zone and caving zone caused by overburden failure, the response characteristics of resistivity vary with the failure degrees at different overburden failure zone and that they are corresponding. The resistivity method used in monitoring the overburden failure can determine the height and the affecting scopes of the cracked zone and caving zone. This can provide reliable techaological guarantee for mining design and safe production.
基金funded by the Major National Scientific Research Plan(2013CB733305,2012CB957703)the National Natural Science Foundation of China(41174066,41131067,41374087,41431070)
文摘The Gravity Recovery and Climate Experiment(GRACE) mission can significantly improve our knowledge of the temporal variability of the Earth's gravity field.We obtained monthly gravity field solutions based on variational equations approach from GPS-derived positions of GRACE satellites and K-band range-rate measurements.The impact of different fixed data weighting ratios in temporal gravity field recovery while combining the two types of data was investigated for the purpose of deriving the best combined solution.The monthly gravity field solution obtained through above procedures was named as the Institute of Geodesy and Geophysics(IGG) temporal gravity field models.IGG temporal gravity field models were compared with GRACE Release05(RL05) products in following aspects:(i) the trend of the mass anomaly in China and its nearby regions within 2005-2010; (ii) the root mean squares of the global mass anomaly during 2005-2010; (iii) time-series changes in the mean water storage in the region of the Amazon Basin and the Sahara Desert between 2005 and 2010.The results showed that IGG solutions were almost consistent with GRACE RL05 products in above aspects(i)-(iii).Changes in the annual amplitude of mean water storage in the Amazon Basin were 14.7 ± 1.2 cm for IGG,17.1 ± 1.3 cm for the Centre for Space Research(CSR),16.4 ± 0.9 cm for the GeoForschungsZentrum(GFZ) and 16.9 ± 1.2 cm for the Jet Propulsion Laboratory(JPL) in terms of equivalent water height(EWH),respectively.The root mean squares of the mean mass anomaly in Sahara were 1.2 cm,0.9 cm,0.9 cm and 1.2 cm for temporal gravity field models of IGG,CSR,GFZ and JPL,respectively.Comparison suggested that IGG temporal gravity field solutions were at the same accuracy level with the latest temporal gravity field solutions published by CSR,GFZ and JPL.
文摘Based on the principle of similarity, water was used to simulate the flow of molten steel to analyze the flow field in a tundish. Several schemes of the tundish' s tracer shape were designed and corresponding water model experiments were conducted. During the experiments, a computer automatically collected data. The comparison of the residence time distribution( RTD ) curves drawn according to the computer-collected data optimized the scheme and photographs originated from the experiments with ink as its tracer. It indicates that the water model can optimize the flow field of the tundish.
基金National Major Scientific and Technological Special Project for"Significant New Drugs Development"(2019ZX09301-005).
文摘[Objectives]To explore the antidepressant effect of Shenwei Ningyu Tablet,a new antidepressant traditional Chinese medicine,on rat chronic stress depression model and mouse tail suspension models.[Methods]Rat chronic stress model:except for the normal group,the rats in other groups were given corresponding chronic stress,and administered by gavage 1 h before modeling,for a total of 21 d.The changes of each indicator before and after the experiment were observed through the body weight change,the sugar water test,and open field test.The relevant hormone levels were detected by radioimmunoassay.Mouse tail suspension depression model:after continuous administration for 7 d,the activity times was recorded with the mouse automatic recorder,and the mouse immobility time was recorded after tail suspension,to explore the effects of each administration group on the tail suspension immobility time of mice.[Results]Chronic stress depression model:21 d after modeling,compared with the normal group,rats in the model group exhibited significantly reduced body weight,sucrose preference index,and horizontal and vertical movement scores(P<0.05).Compared with the model group,the low-dose Shenwei Ningyu Tablets group had significant differences in the sugar water test,horizontal and vertical movement scores(P<0.05).In addition,all three dose groups of Shenwei Ningyu Tablets could effectively reduce the content of CRF in chronic stress model rats,and the low dose group could significantly reduce the ACTH level in model rats(P<0.05).Mouse tail suspension depression model:the immobility time after tail suspension in each administration group was significantly different from that in the model group(P<0.05).[Conclusions]Shenwei Ningyu Tablets has a certain anti-depression effect on both the rat chronic stress depression model and the mouse tail suspension depression model.