Earthquake early warning （EEW） systems are one of the most effective ways to reduce earthquake disaster. Earthquake magnitude estimation is one of the most important and also the most difficult parts of the entire E...Earthquake early warning （EEW） systems are one of the most effective ways to reduce earthquake disaster. Earthquake magnitude estimation is one of the most important and also the most difficult parts of the entire EEW system. In this paper, based on 142 earthquake events and 253 seismic records that were recorded by the KiK-net in Japan, and aftershocks of the large Wenchuan earthquake in Sichuan, we obtained earthquake magnitude estimation relationships using the τe and Pa methods. The standard variances of magnitude calculation of these two formulas are ±0.65 and ±0.56, respectively. The Pd value can also be used to estimate the peak ground motion of velocity, then warning information can be released to the public rapidly, according to the estimation results. In order to insure the stability and reliability of magnitude estimation results, we propose a compatibility test according to the natures of these two parameters. The reliability of the early warning information is significantly improved though this test.展开更多
According to earthquake catalog records of Fujian Seismic Network, the Tnow method and the fourstation continuous location method put forward by Jin Xing are inspected by using P-wave arrival information of the first ...According to earthquake catalog records of Fujian Seismic Network, the Tnow method and the fourstation continuous location method put forward by Jin Xing are inspected by using P-wave arrival information of the first four stations in each earthquake. It shows that the fourstation continuous location method can locate more seismic events than the Tnow method. By analyzing the results, it is concluded that the reason for this is that the Tnow method makes use of information from stations without being triggered, while some stations failed to be reflected in earthquake catalog because of discontinuous records or unclear records of seismic phases. For seismic events whose location results can be given, there is no obvious difference in location results of the two methods and positioning deviation of most seismic events is also not significant. For earthquakes outside the network, the positioning deviation may amplify as the epicentral distance enlarges, which may relate to the situation that the seismic stations are centered on one side of epicenter and the opening angle between seismic stations used for location and epicenter is small.展开更多
In this paper,according to the Fujian Seismic Network earthquake catalog records,the T now method and the Four Stations Continuous Location method( hereinafter called FSCL)put forward by Jin Xing are inspected by usin...In this paper,according to the Fujian Seismic Network earthquake catalog records,the T now method and the Four Stations Continuous Location method( hereinafter called FSCL)put forward by Jin Xing are inspected by using P-wave arrival information of the first four stations of each seismic event. Results show that for earthquakes within the network,both methods can obtain similar location results and location deviations are small for the majority of the events. For earthquakes outside the network,the location deviation may be amplified as the epicentral distance increases,owing to the seismic station distribution which spread toward the side of the epicenter and the small opening angle between seismic stations used for locating and epicenter. For the FSCL method,the impacts of the wave velocity on the location results may be significant for earthquakes outside the network.Thus,selecting a velocity model which is similar to the actual structure of the wave velocity will contribute to improving location results of earthquakes. The FSCL method can locate more seismic events than the T now method. It concludes that the T now method makes use of mistake information from some non-triggering stations in earthquake catalog,and some P-wave arrivals are not included in the earthquake catalog due to discontinuous records or unclear records of the seismic phase,which induces incorrect location.展开更多
In order to improve the survivability of the aircraft,conceptual design and radar cross section（RCS） performance research are done. The CATIA software is used to design the 3D digital model of the shipborne early wa...In order to improve the survivability of the aircraft,conceptual design and radar cross section（RCS） performance research are done. The CATIA software is used to design the 3D digital model of the shipborne early warning aircraft, and some measures are taken to reduce the RCS characteristics of the early warning aircraft at the same time. Based on the physical optics method and the equivalent electromagnetic flow method,the aircraft＇s RCS characteristics and strength distribution characteristics are simulated numerically, and compared with the foreign advanced shipborne early warning aircraft. The simulation results show that under the X radar band, when the incident wave pitching angle is 0？, compared with the foreign advanced shipborne early warning aircraft, the forward RCS average value of the conceptual shipborne early warning aircraft is reduced to 24.49%, the lateral RCS average value is reduced to 5.04%, and the backward RCS average value is reduced to 39.26%. The research results of this paper are expected to provide theoretical basis and technical support for the conceptual design and the stealth design of the shipborne early warning aircraft.展开更多
A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of ...A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of high time cost in adopting a rational-based optimal design method for ship structural design. Furthermore,the method was verified by its effective application in optimization of the mid-ship section of a container ship. A full 3-D FEM model of a ship,suffering static and quasi-static loads, was used as the analyzing object for evaluating the structural performance of the mid-ship module, including static strength and buckling performance. Research results reveal that this new method could substantially reduce the computational cost of the rational-based optimization problem without decreasing its accuracy, which increases the feasibility and economic efficiency of using a rational-based optimal design method in ship structural design.展开更多
According to the index early warning method, a commercial bank loans risk early warning system based on BP neural networks is proposed. The warning signal is mainly involved with the financial situation signal of loan...According to the index early warning method, a commercial bank loans risk early warning system based on BP neural networks is proposed. The warning signal is mainly involved with the financial situation signal of loaning corporation. Except the structure description of the system structure the demonstration of attemptive designing is also elaborated.展开更多
By analyzing the heavy fog data in Chizhou City in recent 50 years(1959-2007),the general rules of meteorological elements variations were found when the heavy fog happened.The meteorological elements included the tem...By analyzing the heavy fog data in Chizhou City in recent 50 years(1959-2007),the general rules of meteorological elements variations were found when the heavy fog happened.The meteorological elements included the temperature,humidity,wind direction,wind speed,air pressure and so on.The conceptual models of high-altitude and ground situation were established when the heavy fog happened in Chizhou City.Based on considering sufficiently the special geographical environment in Chizhou City,we found the key factors which affected the local heavy fog via the relative analyses.By using the statistical forecast methods which included the second-level judgment method and regression method of event probability and so on,the forecast mode equation of heavy fog was established.Moreover,the objective forecast system of heavy fog in Chizhou City was also manufactured.It provided the basis and platform which could be referred for the heavy fog forecast,service and the release of early-warning signal.展开更多
This paper optimizes the meteorological drought assessment method in Fujian Province, China, making it more suitable for long-term serial drought statistics. Using the precipitation data of Pingtan National Basic Weat...This paper optimizes the meteorological drought assessment method in Fujian Province, China, making it more suitable for long-term serial drought statistics. Using the precipitation data of Pingtan National Basic Weather Station from 1971 to 2016, according to the optimized meteorological drought assessment method, statistics Pingtan meteorological drought process, and its characteristics analysis;through the multi-model integrated forecasting super-aggregate method, the 2011-2014 Fujian precipitation reality and the European Center, T639, WRF, Japan and other numerical forecast products were used for comparative analysis. The use of multiple regression method was used to forecast precipitation, by the localized precipitation correction scheme. The early warning method of single station meteorological drought process based on precipitation reality and precipitation forecast is obtained, and the platformization idea is proposed.展开更多
Objective:The objective of this study was to construct an early warning system(EWS)to facilitate risk assessment,early identification,and appropriate treatment of enteral nutrition feeding intolerance(FI)in patients w...Objective:The objective of this study was to construct an early warning system(EWS)to facilitate risk assessment,early identification,and appropriate treatment of enteral nutrition feeding intolerance(FI)in patients with stroke,so as to provide a reference for risk classification standards and interventions toward a complete EWSs for nursing care of stroke.Materials and Methods:Based on evidence and clinical nursing practice,a structured expert consultation method was adopted on nine experts over two rounds of consultation.Statistical analysis was used to determine the early warning index for FI in patients with stroke.Results:The expert authority coefficient was 0.89;the coefficients of variation for the two rounds of consultation were 0.088-0.312 and 0.096-0.214,respectively.There were significant differences in the Kendall’s concordance coefficient(P<0.05).Finally,22 items in five dimensions of patient age,disease,treatment,biochemical,and enteral nutrition-related factors were identified.Conclusion:The early warning index for FI in patients with a history of stroke is valid and practical.It provides a reference for the early clinical identification of FI risk.展开更多
With the continuous development of economy and society and the speeding up development of industrial industry, people's living standards are gradually improving, which leads to the increasing discharge of domestic...With the continuous development of economy and society and the speeding up development of industrial industry, people's living standards are gradually improving, which leads to the increasing discharge of domestic waste and industrial waste, so the working pressure of sewage treatment plants invisibly increases. Sewage treatment plant is the concentration of waste treatment and it will produce a large number of wastes generated by the accumulation of odor, that is, waste gas, with the characteristics of strong diffusion. Therefore, if the wastewater treatment plant can not properly treat these waste gases in time, it is easy to cause large-scale air pollution. If people live in this odor environment for a long time, it will seriously harm their health. Starting from waste gas treatment methods, do multi-level deodorization and purification of waste gas, which is the key measure to effectively help improve people's quality of life.展开更多
On the basis of expounding the status quo of China's orange drought warning model research,according to the real-time monitoring data of Beibei Orangery in Chongqing City from June to August in 2010,by using facto...On the basis of expounding the status quo of China's orange drought warning model research,according to the real-time monitoring data of Beibei Orangery in Chongqing City from June to August in 2010,by using factor analysis and principal component regression,we construct the drought warning model of Beibei Orangery in Chongqing City,and we conduct test and correction on drought warning model by using MAPE principle of assessment and prediction accuracy and the real-time monitoring data of September.The results show that as for the prediction of orange drought,the model has strong credibility.If we conduct continuous dynamic monitoring on the relevant indices regarding orange drought by virtue of this model,and pay attention to the analysis of variation trend of prediction value,then it will be more practical;the warning effect,to some extent,further indicates that using factor analysis and principal component analysis method to conduct drought warning is rational;as the prediction model is static and linear,so we should perfect model to promote the accuracy and practicality of model.展开更多
为了破解低气压下动力锂离子电池热失控预警指标不精准与预警等级不科学的问题,搭建了预警试验平台,试验装置选取UL9540A支持的82 L定容燃烧弹。结果表明,相同荷电状态(State of Charge,SOC)条件下,高SOC电池在低气压环境下的开阀时刻...为了破解低气压下动力锂离子电池热失控预警指标不精准与预警等级不科学的问题,搭建了预警试验平台,试验装置选取UL9540A支持的82 L定容燃烧弹。结果表明,相同荷电状态(State of Charge,SOC)条件下,高SOC电池在低气压环境下的开阀时刻早于常气压。根据锂离子电池灾变过程的紧急程度,提出综合温度(θ_(C))超过自产热隔膜融化、电池正极分解和开阀放气温度以及电压(U)第一次骤降10%作为热失控预警的判定条件。通过皮尔逊相关系数法,筛选出池体安全阀口温度(θ_(2))、池体正极侧中心温度(θ_(4))、电压(U)和气压(p)四个预警指标构建多元动态预警方法,可科学预测单体三元动力锂离子电池热失控从自产热到热失控的危险过程,为低气压下动力锂离子电池安全应用提供理论和技术支撑。展开更多
文摘Earthquake early warning （EEW） systems are one of the most effective ways to reduce earthquake disaster. Earthquake magnitude estimation is one of the most important and also the most difficult parts of the entire EEW system. In this paper, based on 142 earthquake events and 253 seismic records that were recorded by the KiK-net in Japan, and aftershocks of the large Wenchuan earthquake in Sichuan, we obtained earthquake magnitude estimation relationships using the τe and Pa methods. The standard variances of magnitude calculation of these two formulas are ±0.65 and ±0.56, respectively. The Pd value can also be used to estimate the peak ground motion of velocity, then warning information can be released to the public rapidly, according to the estimation results. In order to insure the stability and reliability of magnitude estimation results, we propose a compatibility test according to the natures of these two parameters. The reliability of the early warning information is significantly improved though this test.
文摘According to earthquake catalog records of Fujian Seismic Network, the Tnow method and the fourstation continuous location method put forward by Jin Xing are inspected by using P-wave arrival information of the first four stations in each earthquake. It shows that the fourstation continuous location method can locate more seismic events than the Tnow method. By analyzing the results, it is concluded that the reason for this is that the Tnow method makes use of information from stations without being triggered, while some stations failed to be reflected in earthquake catalog because of discontinuous records or unclear records of seismic phases. For seismic events whose location results can be given, there is no obvious difference in location results of the two methods and positioning deviation of most seismic events is also not significant. For earthquakes outside the network, the positioning deviation may amplify as the epicentral distance enlarges, which may relate to the situation that the seismic stations are centered on one side of epicenter and the opening angle between seismic stations used for location and epicenter is small.
基金funded by the National Key Technology R&D Program of China(2009BAK55B02)
文摘In this paper,according to the Fujian Seismic Network earthquake catalog records,the T now method and the Four Stations Continuous Location method( hereinafter called FSCL)put forward by Jin Xing are inspected by using P-wave arrival information of the first four stations of each seismic event. Results show that for earthquakes within the network,both methods can obtain similar location results and location deviations are small for the majority of the events. For earthquakes outside the network,the location deviation may be amplified as the epicentral distance increases,owing to the seismic station distribution which spread toward the side of the epicenter and the small opening angle between seismic stations used for locating and epicenter. For the FSCL method,the impacts of the wave velocity on the location results may be significant for earthquakes outside the network.Thus,selecting a velocity model which is similar to the actual structure of the wave velocity will contribute to improving location results of earthquakes. The FSCL method can locate more seismic events than the T now method. It concludes that the T now method makes use of mistake information from some non-triggering stations in earthquake catalog,and some P-wave arrivals are not included in the earthquake catalog due to discontinuous records or unclear records of the seismic phase,which induces incorrect location.
基金supported by the National Natural Science Foundation of China(51375490)
文摘In order to improve the survivability of the aircraft,conceptual design and radar cross section（RCS） performance research are done. The CATIA software is used to design the 3D digital model of the shipborne early warning aircraft, and some measures are taken to reduce the RCS characteristics of the early warning aircraft at the same time. Based on the physical optics method and the equivalent electromagnetic flow method,the aircraft＇s RCS characteristics and strength distribution characteristics are simulated numerically, and compared with the foreign advanced shipborne early warning aircraft. The simulation results show that under the X radar band, when the incident wave pitching angle is 0？, compared with the foreign advanced shipborne early warning aircraft, the forward RCS average value of the conceptual shipborne early warning aircraft is reduced to 24.49%, the lateral RCS average value is reduced to 5.04%, and the backward RCS average value is reduced to 39.26%. The research results of this paper are expected to provide theoretical basis and technical support for the conceptual design and the stealth design of the shipborne early warning aircraft.
基金Supported by the Project of Ministry of Education and Finance(No.200512)the Project of the State Key Laboratory of ocean engineering(GKZD010053-10)
文摘A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of high time cost in adopting a rational-based optimal design method for ship structural design. Furthermore,the method was verified by its effective application in optimization of the mid-ship section of a container ship. A full 3-D FEM model of a ship,suffering static and quasi-static loads, was used as the analyzing object for evaluating the structural performance of the mid-ship module, including static strength and buckling performance. Research results reveal that this new method could substantially reduce the computational cost of the rational-based optimization problem without decreasing its accuracy, which increases the feasibility and economic efficiency of using a rational-based optimal design method in ship structural design.
基金Supported by the National Science Foundation of China(Approved NO.79770086)
文摘According to the index early warning method, a commercial bank loans risk early warning system based on BP neural networks is proposed. The warning signal is mainly involved with the financial situation signal of loaning corporation. Except the structure description of the system structure the demonstration of attemptive designing is also elaborated.
文摘By analyzing the heavy fog data in Chizhou City in recent 50 years(1959-2007),the general rules of meteorological elements variations were found when the heavy fog happened.The meteorological elements included the temperature,humidity,wind direction,wind speed,air pressure and so on.The conceptual models of high-altitude and ground situation were established when the heavy fog happened in Chizhou City.Based on considering sufficiently the special geographical environment in Chizhou City,we found the key factors which affected the local heavy fog via the relative analyses.By using the statistical forecast methods which included the second-level judgment method and regression method of event probability and so on,the forecast mode equation of heavy fog was established.Moreover,the objective forecast system of heavy fog in Chizhou City was also manufactured.It provided the basis and platform which could be referred for the heavy fog forecast,service and the release of early-warning signal.
文摘This paper optimizes the meteorological drought assessment method in Fujian Province, China, making it more suitable for long-term serial drought statistics. Using the precipitation data of Pingtan National Basic Weather Station from 1971 to 2016, according to the optimized meteorological drought assessment method, statistics Pingtan meteorological drought process, and its characteristics analysis;through the multi-model integrated forecasting super-aggregate method, the 2011-2014 Fujian precipitation reality and the European Center, T639, WRF, Japan and other numerical forecast products were used for comparative analysis. The use of multiple regression method was used to forecast precipitation, by the localized precipitation correction scheme. The early warning method of single station meteorological drought process based on precipitation reality and precipitation forecast is obtained, and the platformization idea is proposed.
基金supported by the Young Teacher Project of the Beijing University of Chinese Medicine(No.:2018-JYB-JS155).
文摘Objective:The objective of this study was to construct an early warning system(EWS)to facilitate risk assessment,early identification,and appropriate treatment of enteral nutrition feeding intolerance(FI)in patients with stroke,so as to provide a reference for risk classification standards and interventions toward a complete EWSs for nursing care of stroke.Materials and Methods:Based on evidence and clinical nursing practice,a structured expert consultation method was adopted on nine experts over two rounds of consultation.Statistical analysis was used to determine the early warning index for FI in patients with stroke.Results:The expert authority coefficient was 0.89;the coefficients of variation for the two rounds of consultation were 0.088-0.312 and 0.096-0.214,respectively.There were significant differences in the Kendall’s concordance coefficient(P<0.05).Finally,22 items in five dimensions of patient age,disease,treatment,biochemical,and enteral nutrition-related factors were identified.Conclusion:The early warning index for FI in patients with a history of stroke is valid and practical.It provides a reference for the early clinical identification of FI risk.
文摘With the continuous development of economy and society and the speeding up development of industrial industry, people's living standards are gradually improving, which leads to the increasing discharge of domestic waste and industrial waste, so the working pressure of sewage treatment plants invisibly increases. Sewage treatment plant is the concentration of waste treatment and it will produce a large number of wastes generated by the accumulation of odor, that is, waste gas, with the characteristics of strong diffusion. Therefore, if the wastewater treatment plant can not properly treat these waste gases in time, it is easy to cause large-scale air pollution. If people live in this odor environment for a long time, it will seriously harm their health. Starting from waste gas treatment methods, do multi-level deodorization and purification of waste gas, which is the key measure to effectively help improve people's quality of life.
文摘On the basis of expounding the status quo of China's orange drought warning model research,according to the real-time monitoring data of Beibei Orangery in Chongqing City from June to August in 2010,by using factor analysis and principal component regression,we construct the drought warning model of Beibei Orangery in Chongqing City,and we conduct test and correction on drought warning model by using MAPE principle of assessment and prediction accuracy and the real-time monitoring data of September.The results show that as for the prediction of orange drought,the model has strong credibility.If we conduct continuous dynamic monitoring on the relevant indices regarding orange drought by virtue of this model,and pay attention to the analysis of variation trend of prediction value,then it will be more practical;the warning effect,to some extent,further indicates that using factor analysis and principal component analysis method to conduct drought warning is rational;as the prediction model is static and linear,so we should perfect model to promote the accuracy and practicality of model.
文摘为了破解低气压下动力锂离子电池热失控预警指标不精准与预警等级不科学的问题,搭建了预警试验平台,试验装置选取UL9540A支持的82 L定容燃烧弹。结果表明,相同荷电状态(State of Charge,SOC)条件下,高SOC电池在低气压环境下的开阀时刻早于常气压。根据锂离子电池灾变过程的紧急程度,提出综合温度(θ_(C))超过自产热隔膜融化、电池正极分解和开阀放气温度以及电压(U)第一次骤降10%作为热失控预警的判定条件。通过皮尔逊相关系数法,筛选出池体安全阀口温度(θ_(2))、池体正极侧中心温度(θ_(4))、电压(U)和气压(p)四个预警指标构建多元动态预警方法,可科学预测单体三元动力锂离子电池热失控从自产热到热失控的危险过程,为低气压下动力锂离子电池安全应用提供理论和技术支撑。
