Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An ...Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed.Firstly,the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns.Then,overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out,and the critical unstable state of multi-caverns can be identified,if the plastic-strain band appeared between caverns during these overloading processes.Thus,the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient.Practical analysis for the Yingliangbao(YLB)hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions,but also identify the caverns’high-risk zone of local instability through localized plastic strain of surrounding rock.This study can provide some reference for the layout design and seismic optimization of underground cavern group.展开更多
Many corporations are complaining that they cannot make decisions correctly. This article describes virtual laboratory (VL), an organization which can help managers make decision. The virtual laboratory based on Intra...Many corporations are complaining that they cannot make decisions correctly. This article describes virtual laboratory (VL), an organization which can help managers make decision. The virtual laboratory based on Intranet uses many methods to draw policies for the corporation by analyzing business processes. It is a tool for learning organization too.展开更多
In order to investigate the atmospheric oxidation processes and the formation of secondary organic aerosol (SOA), an indoor environmental reaction smog chamber are constructed and characterized. The system consists ...In order to investigate the atmospheric oxidation processes and the formation of secondary organic aerosol (SOA), an indoor environmental reaction smog chamber are constructed and characterized. The system consists of the collapsible ~830 L FEP Teflon film main reactor, in which the atmospheric chemical reactions take place and the formation of SOA occurs under the simulated atmospheric conditions, and the diverse on-line gas- and particle-phase instrumentation, such as the proton transfer reaction mass spectrometer, the synchrotron radiation photoionization mass spectrometer, the aerosol laser time-of-flight mass spectrometer, and other traditional commercial instruments. The initial characterization experiments are described, concerning the temperature and ultraviolet light intensity, the reactivity of the pure air, the wall loss rates of gaseous compounds and particulate matter. And the initial evaluation experiments for SOA yields from the ozonolysis of α-pinene and for mass spectra of the products resulting from the photooxidation of OH initiated isoprene are also presented, which indicate the applicability of this facility on the studies of gas-phase chemical mechanisms as well as the formation of SOA expected in the atmosphere.展开更多
Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 (carbon dioxide) emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO...Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 (carbon dioxide) emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO2 is the main component of greenhouse gases and the main culprit of causing the greenhouse effect. The ocean is a huge repository of carbon, water can dissolve a large amount of CO2, in the ocean, a large number of plants and planktonic algae absorb CO2 to produce 02, It is a very large gathering place (sink). At the same time, CO2 aggregation in the ocean seawater acidity increases, impact on fishery resources, sources and sinks of CO2 were discussed in the paper.展开更多
As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and...As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and global change. With development of mathematical models that simulate changes in soil organic carbon, there have been considerable advances in understanding soil organic carbon dynamics. This paper mainly reviewed the composition of soil organic matter and its influenced factors, and recommended some soil organic matter models worldwide. Based on the analyses of the developed results at home and abroad, it is suggested that future soil organic matter models should be developed toward based-process models, and not always empirical ones. The models are able to reveal their interaction between soil carbon systems, climate and land cover by technique and methods of GIS (Geographical Information System) and RS (Remote Sensing). These models should be developed at a global scale, in dynamically describing the spatial and temporal changes of soil organic matter cycle. Meanwhile, the further researches on models should be strengthen for providing theory basis and foundation in making policy of green house gas emission in China.展开更多
An underground heat storage system in a double-film-covered greenhouse and an adjacent greenhouse without the heat storage system were designed on the basis of plant physiology to reduce the energy consumption in gree...An underground heat storage system in a double-film-covered greenhouse and an adjacent greenhouse without the heat storage system were designed on the basis of plant physiology to reduce the energy consumption in greenhouses. The results indicated that the floor temperature was respectively 5.2℃, 4.6℃ and 2.0 ℃ higher than that of the soil in the adjacent reference greenhouse after heat storage in a clear, cloudy and overcast sky in winter. Results showed that the temperature and humidity were feasible for plant growth in the heat saving greenhouse.展开更多
With urbanization accelerating, people’s living standard is growing and their demands on lifestyle are improving accordingly. The research proposed housing gardening system based on low-carbon greenhouse technology f...With urbanization accelerating, people’s living standard is growing and their demands on lifestyle are improving accordingly. The research proposed housing gardening system based on low-carbon greenhouse technology from perspectives of air quality, food safety and environment-friendliness. Besides, the research detailed designs of planting system, water circulation system and lighting system by interpretation on low-carbon greenhouse technology, microclimate and housing gardening system.展开更多
A new impedance controller based on the dynamic surface control-backstepping technique to actualize the anticipant dynamic relationship between the motion of end-effector and the external torques was presented. Compar...A new impedance controller based on the dynamic surface control-backstepping technique to actualize the anticipant dynamic relationship between the motion of end-effector and the external torques was presented. Comparing with the traditional backstepping method that has "explosion of terms" problem, the new proposed control system is a combination of the dynamic surface control technique and the backstepping. The dynamic surface control (DSC) technique can resolve the "explosion of terms" problem that is caused by differential coefficient calculation in the model, and the problem can bring a complexity that will cause the backstepping method hardly to be applied to the practical application, especially to the multi-joint robot. Finally, the validity of the method was proved in the laboratory environment that was set up on the 5-DOF (degree of freedom) flexible joint robot. Tracking errors of DSC-backstepping impedance control that were 2.0 and 1.5 mm are better than those of backstepping impedance control which were 3.5 and 2.5 mm in directions X, Y in free space, respectively. And the anticipant Cartesian impedance behavior and compliant behavior were nchieved successfully as depicted theoretically.展开更多
Indoor localization is very critical for medical care applications, e.g., the patient localization or tracking inside the building of the hospital. Traditional Radio Frequency Identification(RFID) technologies are ver...Indoor localization is very critical for medical care applications, e.g., the patient localization or tracking inside the building of the hospital. Traditional Radio Frequency Identification(RFID) technologies are very popular in this area since their cost is very low. In such technologies, each tag acts as the transmitter and the Radio Signal Strength Indicator(RSSI) information is measured from the readers. However, RSSI information suffers severely from the multi- path phenomenon. As a result, if in a very large area, the localization accuracy will be affected seriously. In order to solve this problem, we introduce Wireless Sensor Networks(WSNs) with only a few nodes, each of which acts as both transmitter and receiver. In such networks, the change of signal strength(referred as dynamic of RSSI) is leveraged to select a cluster of reference tags as candidates. Then the fi nal target location is estimated by using the RSSI relationships between the target tag and candidate reference tags. Thus, the localization accuracy and scalability are able to be improved. We proposed two algorithms, SA-LANDMARC, and COCKTAIL. Experiments show that the localization accuracy of the two algorithms can reach 0.7m and 0.45 m, respectively. Compared to most traditional Radio Frequency(RF)-based approaches, the localization accuracy is improved at least 50%.展开更多
The process of urban building reviewing is a collaborative work by a group of urban planning staffs and land managers who are working with different departments of a organization. There are three ingredients for impro...The process of urban building reviewing is a collaborative work by a group of urban planning staffs and land managers who are working with different departments of a organization. There are three ingredients for improving the work efficiency, i.e., agile communication and interactive mechanisms, good information, effective processing and visualizing tools. In order to build a computer supported collaborative work (CSCW) system in Urban Planning and Land Administration Bureau in Changzhou Municapality, GIS was integrated with office automation (OA). The workflow and organizational structure had been re-engineered to meet the requirement of application of the new technology. Federated databases were constructed by assembling disparate sources of heterogeneous spatial and attribute data. Easy access to the data by contents was developed for promoting information sharing within the organization. Specific desktop spatial data handling tools were provided for delineating land lots or building layouts on large-scale digital maps. Office automation functions, including applications registering, reasonableness checking, opinions giving and exchanging, were developed and they permit printing and documents filing. The work efficiency in the organization has been improved by introducing the computer-based collaborative building reviewing system.展开更多
Hepatic portal venous gas is most often associated with extensive bowel necrosis due to mesenteric infarction.Mortality exceeds 75% with this condition.The most common precipitating factors include ischemia,intra-abdo...Hepatic portal venous gas is most often associated with extensive bowel necrosis due to mesenteric infarction.Mortality exceeds 75% with this condition.The most common precipitating factors include ischemia,intra-abdominal abscesses and inflammatory bowel disease.In this report,we present a 75-year-old woman with extensive hepatic portal and mesenteric venous gas due to colonic diverticulitis.She had a 10-year history of type diabetes mellitus and hypertension.She was treated by sigmoid resection and Hartmann's procedure and discharged from the hospital without any complications.展开更多
In this paper we prove the equivalence of two conditions for geometry,which are used in the investigation of the quotient structure of geometry. Furthermore we deal with the relation between the connectedness of compl...In this paper we prove the equivalence of two conditions for geometry,which are used in the investigation of the quotient structure of geometry. Furthermore we deal with the relation between the connectedness of complices and that of chamber systems.展开更多
Debris flows include a great diversity of grain sizes with inherent features such as inverse grading, particle size segregation, and liquefaction of fine sediment. The liquefaction of fine sediment affects the fluidit...Debris flows include a great diversity of grain sizes with inherent features such as inverse grading, particle size segregation, and liquefaction of fine sediment. The liquefaction of fine sediment affects the fluidity of debris flows, although the behavior and influence of fine sediment in debris flows have not been examined sufficiently. This study used flume tests to detect the effect of fine sediment on the fluidity of laboratory debris flows consisting of particles with various diameters. From the experiments, the greatest sediment concentration and flow depth were observed in the debris flows mixed with fine sediment indicating increased flow resistance. The experimental friction coefficient was then compared with the theoretical friction coefficient derived by substituting the experimental values into the constitutive equations for debris flow. The theoretical friction coefficient was obtained from two models with different fine-sediment treatments: assuming that all of the fine sediments were solid particles or that the particles consisted of a fluid phase involving pore water liquefaction. From the comparison of the friction coefficients, a fully liquefaction state was detected for the fine particle mixture. When the mixing ratio and particle size of the fine sediment were different, some other eases were considered to be in a partially liquefied transition state. These results imply that the liquefaction of fine sediment in debris flows was induced not only by the geometric conditions such as particle sizes, but also by the flow conditions.展开更多
An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform...An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform of the IPS is designed,which consists of the light-emitting diode( LED)based transmitter,the receiver and the positioning server. To reduce the impact caused by measurement errors,both inertial sensing data and the received signal strength( RSS) from the VLC are calibrated. Then,a practical propagation model is established to obtain the distance between the transmitter and the receiver from the RSS measurements. Furthermore,a hybrid positioning algorithm is proposed by using the adaptive Kalman filter( AKF) and the weighted least squares( WLS)trilateration to estimate the positions of the mobile targets.Experimental results show that the developed IPS using the proposed hybrid positioning algorithm can extend the localization area of VLC,mitigate the IMU drifts and improve the positioning accuracy of mobile targets.展开更多
基金Project(2023YFC2907204)supported by the National Key Research and Development Program of ChinaProject(52325905)supported by the National Natural Science Foundation of ChinaProject(DJ-HXGG-2023-16)supported by the Key Technology Research Projects of Power China。
文摘Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed.Firstly,the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns.Then,overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out,and the critical unstable state of multi-caverns can be identified,if the plastic-strain band appeared between caverns during these overloading processes.Thus,the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient.Practical analysis for the Yingliangbao(YLB)hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions,but also identify the caverns’high-risk zone of local instability through localized plastic strain of surrounding rock.This study can provide some reference for the layout design and seismic optimization of underground cavern group.
文摘Many corporations are complaining that they cannot make decisions correctly. This article describes virtual laboratory (VL), an organization which can help managers make decision. The virtual laboratory based on Intranet uses many methods to draw policies for the corporation by analyzing business processes. It is a tool for learning organization too.
基金This work was supported by the Natural Science Foundation of Anhui Province, China (No.1208085MD59), the National Natural Science Foundation of China (No.U1232209, No.41175121, and No.21307137), the Presidential Foundation of Hefei Institutes of Physical Science, Chinese Academy of Sciences, China (No.YZJJ201302), and the Knowledge Innovation Foundation of the Chinese Academy of Sciences (No.KJCX2-YW-N24).
文摘In order to investigate the atmospheric oxidation processes and the formation of secondary organic aerosol (SOA), an indoor environmental reaction smog chamber are constructed and characterized. The system consists of the collapsible ~830 L FEP Teflon film main reactor, in which the atmospheric chemical reactions take place and the formation of SOA occurs under the simulated atmospheric conditions, and the diverse on-line gas- and particle-phase instrumentation, such as the proton transfer reaction mass spectrometer, the synchrotron radiation photoionization mass spectrometer, the aerosol laser time-of-flight mass spectrometer, and other traditional commercial instruments. The initial characterization experiments are described, concerning the temperature and ultraviolet light intensity, the reactivity of the pure air, the wall loss rates of gaseous compounds and particulate matter. And the initial evaluation experiments for SOA yields from the ozonolysis of α-pinene and for mass spectra of the products resulting from the photooxidation of OH initiated isoprene are also presented, which indicate the applicability of this facility on the studies of gas-phase chemical mechanisms as well as the formation of SOA expected in the atmosphere.
文摘Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 (carbon dioxide) emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO2 is the main component of greenhouse gases and the main culprit of causing the greenhouse effect. The ocean is a huge repository of carbon, water can dissolve a large amount of CO2, in the ocean, a large number of plants and planktonic algae absorb CO2 to produce 02, It is a very large gathering place (sink). At the same time, CO2 aggregation in the ocean seawater acidity increases, impact on fishery resources, sources and sinks of CO2 were discussed in the paper.
基金The research is funded by National Natural Science Foundation (40231016) and Canadian International Development Agency (CIDA).
文摘As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and global change. With development of mathematical models that simulate changes in soil organic carbon, there have been considerable advances in understanding soil organic carbon dynamics. This paper mainly reviewed the composition of soil organic matter and its influenced factors, and recommended some soil organic matter models worldwide. Based on the analyses of the developed results at home and abroad, it is suggested that future soil organic matter models should be developed toward based-process models, and not always empirical ones. The models are able to reveal their interaction between soil carbon systems, climate and land cover by technique and methods of GIS (Geographical Information System) and RS (Remote Sensing). These models should be developed at a global scale, in dynamically describing the spatial and temporal changes of soil organic matter cycle. Meanwhile, the further researches on models should be strengthen for providing theory basis and foundation in making policy of green house gas emission in China.
基金Project (No. 20050912) supported by the Education Department of Zhejiang Province, China
文摘An underground heat storage system in a double-film-covered greenhouse and an adjacent greenhouse without the heat storage system were designed on the basis of plant physiology to reduce the energy consumption in greenhouses. The results indicated that the floor temperature was respectively 5.2℃, 4.6℃ and 2.0 ℃ higher than that of the soil in the adjacent reference greenhouse after heat storage in a clear, cloudy and overcast sky in winter. Results showed that the temperature and humidity were feasible for plant growth in the heat saving greenhouse.
文摘With urbanization accelerating, people’s living standard is growing and their demands on lifestyle are improving accordingly. The research proposed housing gardening system based on low-carbon greenhouse technology from perspectives of air quality, food safety and environment-friendliness. Besides, the research detailed designs of planting system, water circulation system and lighting system by interpretation on low-carbon greenhouse technology, microclimate and housing gardening system.
基金Project(2006AA04Z228) supported by the National High-Tech Research and Development Program of ChinaProject(PCSIRT) supported by Program for Changjiang Scholars and Innovative Research Team in University
文摘A new impedance controller based on the dynamic surface control-backstepping technique to actualize the anticipant dynamic relationship between the motion of end-effector and the external torques was presented. Comparing with the traditional backstepping method that has "explosion of terms" problem, the new proposed control system is a combination of the dynamic surface control technique and the backstepping. The dynamic surface control (DSC) technique can resolve the "explosion of terms" problem that is caused by differential coefficient calculation in the model, and the problem can bring a complexity that will cause the backstepping method hardly to be applied to the practical application, especially to the multi-joint robot. Finally, the validity of the method was proved in the laboratory environment that was set up on the 5-DOF (degree of freedom) flexible joint robot. Tracking errors of DSC-backstepping impedance control that were 2.0 and 1.5 mm are better than those of backstepping impedance control which were 3.5 and 2.5 mm in directions X, Y in free space, respectively. And the anticipant Cartesian impedance behavior and compliant behavior were nchieved successfully as depicted theoretically.
基金supported in part by China NSFC Grant 61202377 and 61170076the Guangdong Natural Science Foundation under Grant 2014A030313553+2 种基金the China National High Technology Research and Development Program 863, under Grant 2015AA015305Joint Funds of the National Natural Science Foundation of China under Grant U1301252Guangdong Province Key Laboratory Project under grant 2012A061400024
文摘Indoor localization is very critical for medical care applications, e.g., the patient localization or tracking inside the building of the hospital. Traditional Radio Frequency Identification(RFID) technologies are very popular in this area since their cost is very low. In such technologies, each tag acts as the transmitter and the Radio Signal Strength Indicator(RSSI) information is measured from the readers. However, RSSI information suffers severely from the multi- path phenomenon. As a result, if in a very large area, the localization accuracy will be affected seriously. In order to solve this problem, we introduce Wireless Sensor Networks(WSNs) with only a few nodes, each of which acts as both transmitter and receiver. In such networks, the change of signal strength(referred as dynamic of RSSI) is leveraged to select a cluster of reference tags as candidates. Then the fi nal target location is estimated by using the RSSI relationships between the target tag and candidate reference tags. Thus, the localization accuracy and scalability are able to be improved. We proposed two algorithms, SA-LANDMARC, and COCKTAIL. Experiments show that the localization accuracy of the two algorithms can reach 0.7m and 0.45 m, respectively. Compared to most traditional Radio Frequency(RF)-based approaches, the localization accuracy is improved at least 50%.
基金Project supported by the National Natural Science Foundation of China(No.49671061)
文摘The process of urban building reviewing is a collaborative work by a group of urban planning staffs and land managers who are working with different departments of a organization. There are three ingredients for improving the work efficiency, i.e., agile communication and interactive mechanisms, good information, effective processing and visualizing tools. In order to build a computer supported collaborative work (CSCW) system in Urban Planning and Land Administration Bureau in Changzhou Municapality, GIS was integrated with office automation (OA). The workflow and organizational structure had been re-engineered to meet the requirement of application of the new technology. Federated databases were constructed by assembling disparate sources of heterogeneous spatial and attribute data. Easy access to the data by contents was developed for promoting information sharing within the organization. Specific desktop spatial data handling tools were provided for delineating land lots or building layouts on large-scale digital maps. Office automation functions, including applications registering, reasonableness checking, opinions giving and exchanging, were developed and they permit printing and documents filing. The work efficiency in the organization has been improved by introducing the computer-based collaborative building reviewing system.
文摘Hepatic portal venous gas is most often associated with extensive bowel necrosis due to mesenteric infarction.Mortality exceeds 75% with this condition.The most common precipitating factors include ischemia,intra-abdominal abscesses and inflammatory bowel disease.In this report,we present a 75-year-old woman with extensive hepatic portal and mesenteric venous gas due to colonic diverticulitis.She had a 10-year history of type diabetes mellitus and hypertension.She was treated by sigmoid resection and Hartmann's procedure and discharged from the hospital without any complications.
文摘In this paper we prove the equivalence of two conditions for geometry,which are used in the investigation of the quotient structure of geometry. Furthermore we deal with the relation between the connectedness of complices and that of chamber systems.
基金supported by Grant-in-Aid for Scientific Research (Grant No.22780140,2010),from the Ministry of Education,Science,Sports,and Culture,of Japan
文摘Debris flows include a great diversity of grain sizes with inherent features such as inverse grading, particle size segregation, and liquefaction of fine sediment. The liquefaction of fine sediment affects the fluidity of debris flows, although the behavior and influence of fine sediment in debris flows have not been examined sufficiently. This study used flume tests to detect the effect of fine sediment on the fluidity of laboratory debris flows consisting of particles with various diameters. From the experiments, the greatest sediment concentration and flow depth were observed in the debris flows mixed with fine sediment indicating increased flow resistance. The experimental friction coefficient was then compared with the theoretical friction coefficient derived by substituting the experimental values into the constitutive equations for debris flow. The theoretical friction coefficient was obtained from two models with different fine-sediment treatments: assuming that all of the fine sediments were solid particles or that the particles consisted of a fluid phase involving pore water liquefaction. From the comparison of the friction coefficients, a fully liquefaction state was detected for the fine particle mixture. When the mixing ratio and particle size of the fine sediment were different, some other eases were considered to be in a partially liquefied transition state. These results imply that the liquefaction of fine sediment in debris flows was induced not only by the geometric conditions such as particle sizes, but also by the flow conditions.
基金The National Natural Science Foundation of China(No.61741102,61471164,61601122)the Fundamental Research Funds for the Central Universities(No.SJLX_160040)
文摘An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform of the IPS is designed,which consists of the light-emitting diode( LED)based transmitter,the receiver and the positioning server. To reduce the impact caused by measurement errors,both inertial sensing data and the received signal strength( RSS) from the VLC are calibrated. Then,a practical propagation model is established to obtain the distance between the transmitter and the receiver from the RSS measurements. Furthermore,a hybrid positioning algorithm is proposed by using the adaptive Kalman filter( AKF) and the weighted least squares( WLS)trilateration to estimate the positions of the mobile targets.Experimental results show that the developed IPS using the proposed hybrid positioning algorithm can extend the localization area of VLC,mitigate the IMU drifts and improve the positioning accuracy of mobile targets.