Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of t...Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of this process were analyzed in this article in terms of general circulation,character of physical quantity and tropical cyclone.The result showed that the precipitation process was a long wave adjustment process and it took place during the transformation process of general circulation turning from the zonal to the radial.During the cloudy-rainy weather process,the Ural mountain ridge and the Western Pacific subtropical high were more abnormally strong and in the further north than that in any other years.The tropical cyclone in the south of the subtropical cyclone activity was more frequent.There was more shortwave in middle latitudes of Asian.The cold air masses Siberia went down south.The cold air masses joined with the current of air in the Lower Yellow River.This led to the lasting cloudy-rainy weather for several days in Shandong.展开更多
Based on tidal data statistical analysis for 20 years of Tanggu Marine Environmental Monitoring Station from 1991 to 2010, we concluded that an average of nearly 10 days of 100 cm above water increase took place at Ti...Based on tidal data statistical analysis for 20 years of Tanggu Marine Environmental Monitoring Station from 1991 to 2010, we concluded that an average of nearly 10 days of 100 cm above water increase took place at Tianjin coast every year. The maximum high tide and average tide of Tianjin coast occurred in summer and autumn, and the maximum water increase also occurred in summer and autumn. Days with water increase more than 100 cm mostly occurred in spring, autumn and winter. Then we summarized the causes of coastal storm surge disaster in Tianjin based on astronomical tide factors, meteorological factors, sea level rise, land subsidence, and geographic factors, et al. Finally, we proposed storm surge disaster prevention measures.展开更多
The first thunderstorm weather appeared in southern Shenyang on May 2,2010 and did not bring about severe lightning disaster for Shenyang region,but forecast service had poor effect without forecasting thunderstorm we...The first thunderstorm weather appeared in southern Shenyang on May 2,2010 and did not bring about severe lightning disaster for Shenyang region,but forecast service had poor effect without forecasting thunderstorm weather accurately.In our paper,the reasons for missing report of this thunderstorm weather were analyzed,and analysis on thunderstorm potential was carried out by means of mesoscale analysis technique,providing technical index and vantage point for the prediction of thunderstorm potential.The results showed that the reasons for missing report of this weather process were as follows:surface temperature at prophase was constantly lower going against the development of convective weather;the interpreting and analyzing ability of numerical forecast product should be improved;the forecast result of T639 model was better than that of Japanese numerical forecast;the study and application of mesoscale analysis technique should be strengthened,and this service was formally developed after thunderstorm weather on June 1,2010.展开更多
By means of MICAPS data from China Meteorological Administration,the weather dynamics causing precipitation enhancement in the middle and lower Yangtze Valley on January 19,2008 was analyzed.The results showed that th...By means of MICAPS data from China Meteorological Administration,the weather dynamics causing precipitation enhancement in the middle and lower Yangtze Valley on January 19,2008 was analyzed.The results showed that the convergence of cold and warm air was the basic condition of precipitation enhancement,and the influence systems of precipitation enhancement were surface inverse trough,850-700 hPa warm shear and 850-500 hPa low trough,while southwest and southeast low jet were the important dynamic mechanisms of precipitation enhancement,and southwest low jet offered abundant water vapor for precipitation enhancement.展开更多
1 INTRODUCTION In summer, different assembly of the intensity, location and vertical structure of the subtropical high and the earlier/later time of its seasonal northwards jump bring about different precipitation pat...1 INTRODUCTION In summer, different assembly of the intensity, location and vertical structure of the subtropical high and the earlier/later time of its seasonal northwards jump bring about different precipitation patterns over China. Therefore, subtropical high activity and its cause during the occurrence of extreme climatic event over China and the cause of China drought/flood are studied to improve weather forecasting.展开更多
The red tide event of 11 ̄28, May in 1987 was caused by Eucampia zoodiacus, a coastal eurythermic phytoplanktou. Results from the field monitoring indicated that during the red tide occurrence the optimal temperature ...The red tide event of 11 ̄28, May in 1987 was caused by Eucampia zoodiacus, a coastal eurythermic phytoplanktou. Results from the field monitoring indicated that during the red tide occurrence the optimal temperature and salinity for the multiplication of the red tide organism were 20 ̄25℃ and 26 ̄28. During the red tide event cell densities in two peak values both reached 3 000×103ind. /din3. Organism number in horizonal distribution increased from the harbour mouth to the inner harbour. Average number of the organism at the monitoring stations in the inner harbour was 2 930×103 md. /dm3 which was 3. 7 and 61 times higher than that at the two control monitoring stations. The organism number in vertical distribution apparently showed stepwise, day and night changes. Daily change of the phytoplankton number with spring and ebb tides exhibited a negative relativity.Major reasons for this red tide event included species competition of red tide organisms, sudden increment in water temperature in short time, sharp decrement in salinity by rainfall, water eutrophication, high contents of stimulating materials such as Fe and Mn, poor water exchange condition and stable synoptic condition, etc.High content of dissolved oxygen and high pH value was resulted from the photosythesis of a great quantity of the red tide organisms.展开更多
Root-cause identification plays a vital role in business decision making by providing effective future directions for the organizations.Aspect extraction and sentiment extraction plays a vital role in identifying the ...Root-cause identification plays a vital role in business decision making by providing effective future directions for the organizations.Aspect extraction and sentiment extraction plays a vital role in identifying the rootcauses.This paper proposes the Ensemble based temporal weighting and pareto ranking(ETP)model for Root-cause identification.Aspect extraction is performed based on rules and is followed by opinion identification using the proposed boosted ensemble model.The obtained aspects are validated and ranked using the proposed aspect weighing scheme.Pareto-rule based aspect selection is performed as the final selection mechanism and the results are presented for business decision making.Experiments were performed with the standard five product benchmark dataset.Performances on all five product reviews indicate the effective performance of the proposed model.Comparisons are performed using three standard state-of-the-art models and effectiveness is measured in terms of F-Measure and Detection rates.The results indicate improved performances exhibited by the proposed model with an increase in F-Measure levels at 1%–15%and detection rates at 4%–24%compared to the state-of-the-art models.展开更多
[Objective]The research aimed to analyze and contrast flood cause in Nenjiang Basin between 2013 and 1998.[Method]Based on meteorological and hydrological data in and around Nenjiang Basin,geographic information syste...[Objective]The research aimed to analyze and contrast flood cause in Nenjiang Basin between 2013 and 1998.[Method]Based on meteorological and hydrological data in and around Nenjiang Basin,geographic information system as data processing platform,statistical methods such as synthesis analysis and correlation analysis were combined to contrast and analyze the flood cause in the Nenjiang Basin between 2013 and1998.[Result]The similarities of two floods in Nenjiang Basin were that rainstorm frequency and summer precipitation were more,and many large and medium-sized reservoirs which undertook the flood control task were running above flood level.In order to protect the safety of reservoir dam,flood discharge volume increased.And the difference was external forcing factor which caused atmospheric circulation abnormality,thus the impact factors of summer more rainfall were not the same.The main reason for more precipitation in Nenjiang Basin in summer of 2013:The northeast cold vortex activity was frequent,and the path was by north;water vapor transport was sufficient at 850 hPa;at 500 hPa,the Eurasian zonal circulation was weak,the West Pacific subtropical high pressure abnormally moved northward,blocking high of the Sea of Okhotsk was obvious,and Heilongjiang region was controlled by negative anomaly in midsummer;East Asian westerly jet location was abnormal at 200 hPa,and East Asian summer monsoon was strong.[Conclusion]The research had very important significance for understanding occurrence rule of flood and improving disaster prevention and mitigation capabilities in Nenjiang Basin.展开更多
[Objective]The research aimed to study climatic change characteristics of sunshine hours in Lianyungang and analyze its formation reason. [Method]Based on monthly sunshine hours,precipitation,cloudiness,haze days and ...[Objective]The research aimed to study climatic change characteristics of sunshine hours in Lianyungang and analyze its formation reason. [Method]Based on monthly sunshine hours,precipitation,cloudiness,haze days and vapor pressure from 7 stations of Lianyungang from 1961 to 2010,monthly,seasonal,annual and interdecadal change trends of the sunshine hours were analyzed by using MK test,linear trend analysis and Morlet wavelet. Meanwhile,the cause of change characteristics was analyzed. [Result] Monthly sunshine hours of Lianyungang showed bimodal distribution,and seasonal and annual sunshine hours had decreasing trend at different degrees. The interdecadal change of sunshine hours showed wave characteristics. The annual sunshine hours had multiple temporal-spatial scale features,and there was an obvious mutation in the late 1980s. Sunshine hours in Lianyungang was closely related to visibility,cloudiness,vapor pressure and haze,and they were important factors causing that sunshine hours significantly declined. [Conclusion]The research could provide reference basis for scientifically developing and using solar energy resource and reasonably adjusting industrial and agricultural structures.展开更多
The analysis of the crack on the HRB400 screw-thread steel surface has been carried out by means of metallographic microscope, scanning electron microscope and EDAX. It is shown that the type of inclusions in the crac...The analysis of the crack on the HRB400 screw-thread steel surface has been carried out by means of metallographic microscope, scanning electron microscope and EDAX. It is shown that the type of inclusions in the crack steel samples is mainly class B oxide, C silicate, and the inclusion size of the majority below 10 μm, and a small number of large inclusions are observed. The content of oxygen in the steel is high, and the carbon segregation is the main reason of the crack formation of HRB400 screw-thread steel. The measures to improve the crack formation of HRB400 screw-thread steel are put forward, which provides a powerful basis for the practical production.展开更多
Some factors (i.e. lithology, topography, climate, the change of population as well as land use during the past 50 years) that could have great influence on the development of gully in the arid-hot basin of Jinshaji...Some factors (i.e. lithology, topography, climate, the change of population as well as land use during the past 50 years) that could have great influence on the development of gully in the arid-hot basin of Jinshajiang valley were investigated. The results show that the factors leading to the strong gully erosion in this area include: the widely distributed Yuanmou group stratum, which promotes the development of gully erosion; the unique geomorphologic configuration that is prone to rock fall and gully erosion; the strong and time-concentrated rainfall; the arid-humid alternate climate characteristics that prepares the ground for the development of fissures in soils; the arid-hot climate that goes against the growth and recovery of vegetation; and the unreasonable and abusive human activities.展开更多
Modern industrial systems are usually in large scale,consisting of massive components and variables that form a complex system topology.Owing to the interconnections among devices,a fault may occur and propagate to ex...Modern industrial systems are usually in large scale,consisting of massive components and variables that form a complex system topology.Owing to the interconnections among devices,a fault may occur and propagate to exert widespread influences and lead to a variety of alarms.Obtaining the root causes of alarms is beneficial to the decision supports in making corrective alarm responses.Existing data-driven methods for alarm root cause analysis detect causal relations among alarms mainly based on historical alarm event data.To improve the accuracy,this paper proposes a causal fusion inference method for industrial alarm root cause analysis based on process topology and alarm events.A Granger causality inference method considering process topology is exploited to find out the causal relations among alarms.The topological nodes are used as the inputs of the model,and the alarm causal adjacency matrix between alarm variables is obtained by calculating the likelihood of the topological Hawkes process.The root cause is then obtained from the directed acyclic graph(DAG)among alarm variables.The effectiveness of the proposed method is verified by simulations based on both a numerical example and the Tennessee Eastman process(TEP)model.展开更多
The geological condition and the original structure feature and foundation design of Wuhan Tianheng building are described. The accident appearance of pile foundation in the construction execution of work is illustrat...The geological condition and the original structure feature and foundation design of Wuhan Tianheng building are described. The accident appearance of pile foundation in the construction execution of work is illustrated. The generating source of this pile foundation accident is analyzed in great details.展开更多
The research analyzed the definition, differences and connection between fog and haze, as well as the formation causes, and the countermeasures were pro- posed, providing references for improving air quality in cities.
A distributed information network with complex network structure always has a challenge of locating fault root causes.In this paper,we propose a novel root cause analysis(RCA)method by random walk on the weighted faul...A distributed information network with complex network structure always has a challenge of locating fault root causes.In this paper,we propose a novel root cause analysis(RCA)method by random walk on the weighted fault propagation graph.Different from other RCA methods,it mines effective features information related to root causes from offline alarms.Combined with the information,online alarms and graph relationship of network structure are used to construct a weighted graph.Thus,this approach does not require operational experience and can be widely applied in different distributed networks.The proposed method can be used in multiple fault location cases.The experiment results show the proposed approach achieves much better performance with 6%higher precision at least for root fault location,compared with three baseline methods.Besides,we explain how the optimal parameter’s value in the random walk algorithm influences RCA results.展开更多
In order to comprehensively understand the water quality in Yinma River Basin,and to analyze the spatial-temporal variation characteristics of water quality over the years and the causes of water pollution,15 sections...In order to comprehensively understand the water quality in Yinma River Basin,and to analyze the spatial-temporal variation characteristics of water quality over the years and the causes of water pollution,15 sections were selected in the Yinma River Basin.Based on the water quality monitoring data in the past decade,7 evaluation indexes including dissolved oxygen(DO),5-day biochemical oxygen demand(BOD_(5)),permanganate index(COD_(MN)),chemical oxygen demand(COD),ammonia nitrogen(NH_(4)-N),total phosphorus(TP)and total nitrogen(TN)were determined,according to the Environmental Quality Standard for Surface Water(GB3838-2002)and the historical monitoring data of rivers.The water quality of 15 sections in Yinma River Basin was comprehensively evaluated,and the water quality categories and the evolution of river water quality were analyzed.The pollution sources of Yinma River Basin were analyzed,and the constructive countermeasures were put forward according to the conclusions.展开更多
Based on data of haze days observed by Puyang Meteorological Station of Henan Province from 1971 to 2012, climatic characteristics, causes and prevention countermeasures of haze in Puyang were discussed. The results s...Based on data of haze days observed by Puyang Meteorological Station of Henan Province from 1971 to 2012, climatic characteristics, causes and prevention countermeasures of haze in Puyang were discussed. The results showed that annual average haze days in Puyang tended to increase slightly over the past 42 years on the whole, and the increasing trend became obvious since the 1990s. Meanwhile, haze days in Puyang showed an obvious seasonal variation, that is, haze mainly appeared in autumn (from September to November) and winter (from December to next February), and it was the most frequent in winter. Haze formation was closely related to meteorological and environment elements. Increase of calm wind in horizontal direction, inversion layer in vertical direction, and increase of suspended particulate matter could lead to aggregation of air pollutants, so that haze days increased. Some countermeasures against haze pollution, such as controlling pollution sources, limiting discharge of vehicle exhaust and industrial gases, and increasing green area, should be adopted to reduce haze harm to air quality and human health.展开更多
The paper discusses the framework for a risk-informed root cause analysis process.Such process enables scaling of the analysis performed based on the risk associated with the undesired event or condition,thereby creat...The paper discusses the framework for a risk-informed root cause analysis process.Such process enables scaling of the analysis performed based on the risk associated with the undesired event or condition,thereby creating tiers of analysis where the greater the risk,the more sophisticated the analysis.In a risk-informed root cause analysis process,a situation is normally not analyzed at a level less than what actually occurred.However,a situation may be investigated as though the consequence were greater than actually happened,especially if only slight differences in circumstances could result in a significantly higher consequence.While operational events or safety issues are normally expected to result only with negligible or marginal actual consequences,many of those would actually have certain potential to develop or propagate into catastrophic events.This potential can be expressed qualitatively or quantitatively.Risk-informing of root cause analysis relies on mapping the event or safety issue into a risk matrix which,traditionally,is a two-dimensional probability-consequence matrix.A new concept employed in the risk matrix for root cause analysis is that,while the probability reflects the observed or expected range of values(retaining,thus,its“traditional”meaning),the consequence reflects not only the observed or materialized impact(such as failure of equipment)but,also,its potential to propagate or develop into highly undesirable final state.The paper presents main elements of risk-informed root cause analysis process and discusses qualitative and quantitative aspects and approaches to determination of risk significance of operational events or safety issues.展开更多
The main contents of this paper is a new trend of employment status and employment difficulties of professional sports graduates in Jilin, and analysis on Jilin Physical graduates' Internal Education Causes of employ...The main contents of this paper is a new trend of employment status and employment difficulties of professional sports graduates in Jilin, and analysis on Jilin Physical graduates' Internal Education Causes of employment difficulties ,and how to effectively promote employment of Jilin education and sports undergraduate and graduate and implement measures. In this paper, we use literature, interview survey method, to analyze five professional employment situations of the graduates (physical education major, professional sports training, human movement science, and social sports professional, traditional sports professional). From this perspective of the internal education, employment difficulties of professional sports graduates are these : the concept of employment is a direct factor behind their employment difficulties ; university entrepreneurship education are indirect factors behind Kyrgyzstan employment difficulties ; training model obsolete is the root cause of their difficulties in finding jobs; college enrollment in recent years is its employment difficulties catalyst. This article analyzes the employment situation relating to education, and proposed employment countenueasures which professional sports graduates adapt to, namely: to meet market demand, improve professional structural adjustment; establish the concept of occupation after the first job; establish their own businesses and Multiple Employment Awareness; create a "multi-skilltype" physical training model.展开更多
This paper analyzes the causes of the offshore strength enhancement of Typhoon Tiange (No. 1713) from four aspects: high and low layer divergence, vertical wind shear, southwest monsoon transport, offshore sea tempera...This paper analyzes the causes of the offshore strength enhancement of Typhoon Tiange (No. 1713) from four aspects: high and low layer divergence, vertical wind shear, southwest monsoon transport, offshore sea temperature and weak cold air. The conclusions are as follows: The high-level airflow divergence enhancement and positive vorticity advection in the offshore, strengthen the middle rise movement of the “Tiange”, and the ascending movement enhances the strength of the “Tiange” by strengthening the lower layer convergence;The high offshore sea temperature and sea temperature are changing temperature, which also has a certain effect on the strengthening of “Tiange” in the offshore;The strengthening of the southwest warm and humid airflow provides sufficient water vapor and energy for the development of “Tiange”, which is beneficial to the maintenance of the typhoon warm heart structure;The intrusion of weak cold air, enhanced the radiation cooperation of the lower typhoon disturbance, which is beneficial to the enhancement of “Tiange”.展开更多
文摘Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of this process were analyzed in this article in terms of general circulation,character of physical quantity and tropical cyclone.The result showed that the precipitation process was a long wave adjustment process and it took place during the transformation process of general circulation turning from the zonal to the radial.During the cloudy-rainy weather process,the Ural mountain ridge and the Western Pacific subtropical high were more abnormally strong and in the further north than that in any other years.The tropical cyclone in the south of the subtropical cyclone activity was more frequent.There was more shortwave in middle latitudes of Asian.The cold air masses Siberia went down south.The cold air masses joined with the current of air in the Lower Yellow River.This led to the lasting cloudy-rainy weather for several days in Shandong.
文摘Based on tidal data statistical analysis for 20 years of Tanggu Marine Environmental Monitoring Station from 1991 to 2010, we concluded that an average of nearly 10 days of 100 cm above water increase took place at Tianjin coast every year. The maximum high tide and average tide of Tianjin coast occurred in summer and autumn, and the maximum water increase also occurred in summer and autumn. Days with water increase more than 100 cm mostly occurred in spring, autumn and winter. Then we summarized the causes of coastal storm surge disaster in Tianjin based on astronomical tide factors, meteorological factors, sea level rise, land subsidence, and geographic factors, et al. Finally, we proposed storm surge disaster prevention measures.
文摘The first thunderstorm weather appeared in southern Shenyang on May 2,2010 and did not bring about severe lightning disaster for Shenyang region,but forecast service had poor effect without forecasting thunderstorm weather accurately.In our paper,the reasons for missing report of this thunderstorm weather were analyzed,and analysis on thunderstorm potential was carried out by means of mesoscale analysis technique,providing technical index and vantage point for the prediction of thunderstorm potential.The results showed that the reasons for missing report of this weather process were as follows:surface temperature at prophase was constantly lower going against the development of convective weather;the interpreting and analyzing ability of numerical forecast product should be improved;the forecast result of T639 model was better than that of Japanese numerical forecast;the study and application of mesoscale analysis technique should be strengthened,and this service was formally developed after thunderstorm weather on June 1,2010.
文摘By means of MICAPS data from China Meteorological Administration,the weather dynamics causing precipitation enhancement in the middle and lower Yangtze Valley on January 19,2008 was analyzed.The results showed that the convergence of cold and warm air was the basic condition of precipitation enhancement,and the influence systems of precipitation enhancement were surface inverse trough,850-700 hPa warm shear and 850-500 hPa low trough,while southwest and southeast low jet were the important dynamic mechanisms of precipitation enhancement,and southwest low jet offered abundant water vapor for precipitation enhancement.
基金Research on Floods-Causing Heavy Rains in the Valley of Huaihe River in 2003, a projectfrom the National Meteorological Center
文摘1 INTRODUCTION In summer, different assembly of the intensity, location and vertical structure of the subtropical high and the earlier/later time of its seasonal northwards jump bring about different precipitation patterns over China. Therefore, subtropical high activity and its cause during the occurrence of extreme climatic event over China and the cause of China drought/flood are studied to improve weather forecasting.
文摘The red tide event of 11 ̄28, May in 1987 was caused by Eucampia zoodiacus, a coastal eurythermic phytoplanktou. Results from the field monitoring indicated that during the red tide occurrence the optimal temperature and salinity for the multiplication of the red tide organism were 20 ̄25℃ and 26 ̄28. During the red tide event cell densities in two peak values both reached 3 000×103ind. /din3. Organism number in horizonal distribution increased from the harbour mouth to the inner harbour. Average number of the organism at the monitoring stations in the inner harbour was 2 930×103 md. /dm3 which was 3. 7 and 61 times higher than that at the two control monitoring stations. The organism number in vertical distribution apparently showed stepwise, day and night changes. Daily change of the phytoplankton number with spring and ebb tides exhibited a negative relativity.Major reasons for this red tide event included species competition of red tide organisms, sudden increment in water temperature in short time, sharp decrement in salinity by rainfall, water eutrophication, high contents of stimulating materials such as Fe and Mn, poor water exchange condition and stable synoptic condition, etc.High content of dissolved oxygen and high pH value was resulted from the photosythesis of a great quantity of the red tide organisms.
文摘Root-cause identification plays a vital role in business decision making by providing effective future directions for the organizations.Aspect extraction and sentiment extraction plays a vital role in identifying the rootcauses.This paper proposes the Ensemble based temporal weighting and pareto ranking(ETP)model for Root-cause identification.Aspect extraction is performed based on rules and is followed by opinion identification using the proposed boosted ensemble model.The obtained aspects are validated and ranked using the proposed aspect weighing scheme.Pareto-rule based aspect selection is performed as the final selection mechanism and the results are presented for business decision making.Experiments were performed with the standard five product benchmark dataset.Performances on all five product reviews indicate the effective performance of the proposed model.Comparisons are performed using three standard state-of-the-art models and effectiveness is measured in terms of F-Measure and Detection rates.The results indicate improved performances exhibited by the proposed model with an increase in F-Measure levels at 1%–15%and detection rates at 4%–24%compared to the state-of-the-art models.
基金Supported by Science and Technology Research Item of Heilongjiang Meteorological Bureau in 2014,China(HQ2014018)
文摘[Objective]The research aimed to analyze and contrast flood cause in Nenjiang Basin between 2013 and 1998.[Method]Based on meteorological and hydrological data in and around Nenjiang Basin,geographic information system as data processing platform,statistical methods such as synthesis analysis and correlation analysis were combined to contrast and analyze the flood cause in the Nenjiang Basin between 2013 and1998.[Result]The similarities of two floods in Nenjiang Basin were that rainstorm frequency and summer precipitation were more,and many large and medium-sized reservoirs which undertook the flood control task were running above flood level.In order to protect the safety of reservoir dam,flood discharge volume increased.And the difference was external forcing factor which caused atmospheric circulation abnormality,thus the impact factors of summer more rainfall were not the same.The main reason for more precipitation in Nenjiang Basin in summer of 2013:The northeast cold vortex activity was frequent,and the path was by north;water vapor transport was sufficient at 850 hPa;at 500 hPa,the Eurasian zonal circulation was weak,the West Pacific subtropical high pressure abnormally moved northward,blocking high of the Sea of Okhotsk was obvious,and Heilongjiang region was controlled by negative anomaly in midsummer;East Asian westerly jet location was abnormal at 200 hPa,and East Asian summer monsoon was strong.[Conclusion]The research had very important significance for understanding occurrence rule of flood and improving disaster prevention and mitigation capabilities in Nenjiang Basin.
基金Supported by Meteorological Youth Fund of Jiangsu Province,China(Q201104)the Project of Science and Technology Bureau in Lianyungang of Jiangsu Province,China(SH1206,SH1013)the Project of Science and Technology Department of Jiangsu Province,China(BE2011720)
文摘[Objective]The research aimed to study climatic change characteristics of sunshine hours in Lianyungang and analyze its formation reason. [Method]Based on monthly sunshine hours,precipitation,cloudiness,haze days and vapor pressure from 7 stations of Lianyungang from 1961 to 2010,monthly,seasonal,annual and interdecadal change trends of the sunshine hours were analyzed by using MK test,linear trend analysis and Morlet wavelet. Meanwhile,the cause of change characteristics was analyzed. [Result] Monthly sunshine hours of Lianyungang showed bimodal distribution,and seasonal and annual sunshine hours had decreasing trend at different degrees. The interdecadal change of sunshine hours showed wave characteristics. The annual sunshine hours had multiple temporal-spatial scale features,and there was an obvious mutation in the late 1980s. Sunshine hours in Lianyungang was closely related to visibility,cloudiness,vapor pressure and haze,and they were important factors causing that sunshine hours significantly declined. [Conclusion]The research could provide reference basis for scientifically developing and using solar energy resource and reasonably adjusting industrial and agricultural structures.
文摘The analysis of the crack on the HRB400 screw-thread steel surface has been carried out by means of metallographic microscope, scanning electron microscope and EDAX. It is shown that the type of inclusions in the crack steel samples is mainly class B oxide, C silicate, and the inclusion size of the majority below 10 μm, and a small number of large inclusions are observed. The content of oxygen in the steel is high, and the carbon segregation is the main reason of the crack formation of HRB400 screw-thread steel. The measures to improve the crack formation of HRB400 screw-thread steel are put forward, which provides a powerful basis for the practical production.
基金the National Key Technologies Research and Development Program in the Eleventh Five-Year Plan of China (2006BAC01A11, 2006BAB04A08)the Open Fund of Key Laboratory of Mountain Hazards and Surface Process, Chinese Academy of Sciences
文摘Some factors (i.e. lithology, topography, climate, the change of population as well as land use during the past 50 years) that could have great influence on the development of gully in the arid-hot basin of Jinshajiang valley were investigated. The results show that the factors leading to the strong gully erosion in this area include: the widely distributed Yuanmou group stratum, which promotes the development of gully erosion; the unique geomorphologic configuration that is prone to rock fall and gully erosion; the strong and time-concentrated rainfall; the arid-humid alternate climate characteristics that prepares the ground for the development of fissures in soils; the arid-hot climate that goes against the growth and recovery of vegetation; and the unreasonable and abusive human activities.
基金supported by the National Natural Science Foundation of China(Nos.61903345 and 61973287)。
文摘Modern industrial systems are usually in large scale,consisting of massive components and variables that form a complex system topology.Owing to the interconnections among devices,a fault may occur and propagate to exert widespread influences and lead to a variety of alarms.Obtaining the root causes of alarms is beneficial to the decision supports in making corrective alarm responses.Existing data-driven methods for alarm root cause analysis detect causal relations among alarms mainly based on historical alarm event data.To improve the accuracy,this paper proposes a causal fusion inference method for industrial alarm root cause analysis based on process topology and alarm events.A Granger causality inference method considering process topology is exploited to find out the causal relations among alarms.The topological nodes are used as the inputs of the model,and the alarm causal adjacency matrix between alarm variables is obtained by calculating the likelihood of the topological Hawkes process.The root cause is then obtained from the directed acyclic graph(DAG)among alarm variables.The effectiveness of the proposed method is verified by simulations based on both a numerical example and the Tennessee Eastman process(TEP)model.
文摘The geological condition and the original structure feature and foundation design of Wuhan Tianheng building are described. The accident appearance of pile foundation in the construction execution of work is illustrated. The generating source of this pile foundation accident is analyzed in great details.
文摘The research analyzed the definition, differences and connection between fog and haze, as well as the formation causes, and the countermeasures were pro- posed, providing references for improving air quality in cities.
基金supported by ZTE Industry-University-Institute Cooperation Funds under Grant No.HC-CN-20201120009。
文摘A distributed information network with complex network structure always has a challenge of locating fault root causes.In this paper,we propose a novel root cause analysis(RCA)method by random walk on the weighted fault propagation graph.Different from other RCA methods,it mines effective features information related to root causes from offline alarms.Combined with the information,online alarms and graph relationship of network structure are used to construct a weighted graph.Thus,this approach does not require operational experience and can be widely applied in different distributed networks.The proposed method can be used in multiple fault location cases.The experiment results show the proposed approach achieves much better performance with 6%higher precision at least for root fault location,compared with three baseline methods.Besides,we explain how the optimal parameter’s value in the random walk algorithm influences RCA results.
文摘In order to comprehensively understand the water quality in Yinma River Basin,and to analyze the spatial-temporal variation characteristics of water quality over the years and the causes of water pollution,15 sections were selected in the Yinma River Basin.Based on the water quality monitoring data in the past decade,7 evaluation indexes including dissolved oxygen(DO),5-day biochemical oxygen demand(BOD_(5)),permanganate index(COD_(MN)),chemical oxygen demand(COD),ammonia nitrogen(NH_(4)-N),total phosphorus(TP)and total nitrogen(TN)were determined,according to the Environmental Quality Standard for Surface Water(GB3838-2002)and the historical monitoring data of rivers.The water quality of 15 sections in Yinma River Basin was comprehensively evaluated,and the water quality categories and the evolution of river water quality were analyzed.The pollution sources of Yinma River Basin were analyzed,and the constructive countermeasures were put forward according to the conclusions.
文摘Based on data of haze days observed by Puyang Meteorological Station of Henan Province from 1971 to 2012, climatic characteristics, causes and prevention countermeasures of haze in Puyang were discussed. The results showed that annual average haze days in Puyang tended to increase slightly over the past 42 years on the whole, and the increasing trend became obvious since the 1990s. Meanwhile, haze days in Puyang showed an obvious seasonal variation, that is, haze mainly appeared in autumn (from September to November) and winter (from December to next February), and it was the most frequent in winter. Haze formation was closely related to meteorological and environment elements. Increase of calm wind in horizontal direction, inversion layer in vertical direction, and increase of suspended particulate matter could lead to aggregation of air pollutants, so that haze days increased. Some countermeasures against haze pollution, such as controlling pollution sources, limiting discharge of vehicle exhaust and industrial gases, and increasing green area, should be adopted to reduce haze harm to air quality and human health.
文摘The paper discusses the framework for a risk-informed root cause analysis process.Such process enables scaling of the analysis performed based on the risk associated with the undesired event or condition,thereby creating tiers of analysis where the greater the risk,the more sophisticated the analysis.In a risk-informed root cause analysis process,a situation is normally not analyzed at a level less than what actually occurred.However,a situation may be investigated as though the consequence were greater than actually happened,especially if only slight differences in circumstances could result in a significantly higher consequence.While operational events or safety issues are normally expected to result only with negligible or marginal actual consequences,many of those would actually have certain potential to develop or propagate into catastrophic events.This potential can be expressed qualitatively or quantitatively.Risk-informing of root cause analysis relies on mapping the event or safety issue into a risk matrix which,traditionally,is a two-dimensional probability-consequence matrix.A new concept employed in the risk matrix for root cause analysis is that,while the probability reflects the observed or expected range of values(retaining,thus,its“traditional”meaning),the consequence reflects not only the observed or materialized impact(such as failure of equipment)but,also,its potential to propagate or develop into highly undesirable final state.The paper presents main elements of risk-informed root cause analysis process and discusses qualitative and quantitative aspects and approaches to determination of risk significance of operational events or safety issues.
文摘The main contents of this paper is a new trend of employment status and employment difficulties of professional sports graduates in Jilin, and analysis on Jilin Physical graduates' Internal Education Causes of employment difficulties ,and how to effectively promote employment of Jilin education and sports undergraduate and graduate and implement measures. In this paper, we use literature, interview survey method, to analyze five professional employment situations of the graduates (physical education major, professional sports training, human movement science, and social sports professional, traditional sports professional). From this perspective of the internal education, employment difficulties of professional sports graduates are these : the concept of employment is a direct factor behind their employment difficulties ; university entrepreneurship education are indirect factors behind Kyrgyzstan employment difficulties ; training model obsolete is the root cause of their difficulties in finding jobs; college enrollment in recent years is its employment difficulties catalyst. This article analyzes the employment situation relating to education, and proposed employment countenueasures which professional sports graduates adapt to, namely: to meet market demand, improve professional structural adjustment; establish the concept of occupation after the first job; establish their own businesses and Multiple Employment Awareness; create a "multi-skilltype" physical training model.
文摘This paper analyzes the causes of the offshore strength enhancement of Typhoon Tiange (No. 1713) from four aspects: high and low layer divergence, vertical wind shear, southwest monsoon transport, offshore sea temperature and weak cold air. The conclusions are as follows: The high-level airflow divergence enhancement and positive vorticity advection in the offshore, strengthen the middle rise movement of the “Tiange”, and the ascending movement enhances the strength of the “Tiange” by strengthening the lower layer convergence;The high offshore sea temperature and sea temperature are changing temperature, which also has a certain effect on the strengthening of “Tiange” in the offshore;The strengthening of the southwest warm and humid airflow provides sufficient water vapor and energy for the development of “Tiange”, which is beneficial to the maintenance of the typhoon warm heart structure;The intrusion of weak cold air, enhanced the radiation cooperation of the lower typhoon disturbance, which is beneficial to the enhancement of “Tiange”.