Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth...Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth interviews with patients and families,anchored by Interactive Patient Par ticipation Theory,to analyze 4 high-severity adverse drug events(ADE)cases.Cases were purposively sampled from 8 communities in China's National Adverse Event Monitor Center(2018-2023).Semi-structured interviews explored patient perspectives,with data analyzed via thematic coding and triangulation against clinical records.Results:Five interconnected themes emerged:(1)erosion of trust,(2)communication breakdowns,(3)information asymmetry,(4)environmental inadequacies,and(5)technological alienation.Notably,75% of participants had≤high school education,and 50% used≥7 medications daily,compounding ADE risks.Conclusions:We considered elements mentioned by theory,exploring trust,communication,information,and suppor t as the root causes.In addition,we added“adaptability to new technology”as an impor tant and necessary component.It is impor tant and necessary to analyze typical adverse drug events from the perspectives of patients.展开更多
Fiber-to-the-Room(FTTR)has emerged as the core architecture for next-generation home and enterprise networks,offering gigabitlevel bandwidth and seamless wireless coverage.However,the complex multi-device topology of ...Fiber-to-the-Room(FTTR)has emerged as the core architecture for next-generation home and enterprise networks,offering gigabitlevel bandwidth and seamless wireless coverage.However,the complex multi-device topology of FTTR networks presents significant chal⁃lenges in identifying sources of network performance degradation and conducting accurate root cause analysis.Conventional approaches often fail to deliver efficient and precise operational improvements.To address this issue,this paper proposes a Transformer-based multi-task learn⁃ing model designed for automated root cause analysis in FTTR environments.The model integrates multidimensional time-series data col⁃lected from access points(APs),enabling the simultaneous detection of APs experiencing performance degradation and the classification of underlying root causes,such as weak signal coverage,network congestion,and signal interference.To facilitate model training and evaluation,a multi-label dataset is generated using a discrete-event simulation platform implemented in MATLAB.Experimental results demonstrate that the proposed Transformer-based multi-task learning model achieves a root cause classification accuracy of 96.75%,significantly outperform⁃ing baseline models including Long Short-Term Memory(LSTM),Gated Recurrent Unit(GRU),Random Forest,and eXtreme Gradient Boost⁃ing(XGBoost).This approach enables the rapid identification of performance degradation causes in FTTR networks,offering actionable in⁃sights for network optimization,reduced operational costs,and enhanced user experience.展开更多
In recent years,microservice architecture has gained increasing popularity.However,due to the complex and dynamically chang⁃ing nature of microservice systems,failure detection has become more challenging.Traditional ...In recent years,microservice architecture has gained increasing popularity.However,due to the complex and dynamically chang⁃ing nature of microservice systems,failure detection has become more challenging.Traditional root cause analysis methods mostly rely on a single modality of data,which is insufficient to cover all failure information.Existing multimodal methods require collecting high-quality la⁃beled samples and often face challenges in classifying unknown failure categories.To address these challenges,this paper proposes a root cause analysis framework based on a masked graph autoencoder(GAE).The main process involves feature extraction,feature dimensionality reduction based on GAE,and online clustering combined with expert input.The method is experimentally evaluated on two public datasets and compared with two baseline methods,demonstrating significant advantages even with 16%labeled samples.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
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 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
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
With the continuous development of transportation, the subway has become a very important means of transportation for people to travel and an important part of reducing road traffic pressure. However, the subway has a...With the continuous development of transportation, the subway has become a very important means of transportation for people to travel and an important part of reducing road traffic pressure. However, the subway has a large traffic volume and a high density in the process of operation. If a traffic accident occurs, it will cause very serious consequences. Therefore, we need to make a scientific and reasonable analysis of the overall factors of the subway mechanical and electrical equipment accident, and take targeted and effective measures to make timely and effective decisions, to prevent the occurrence of subway operation accidents, to ensure the safety of people's lives and property, and to ensure that national interests are not lost.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
Root cause analysis （RCA） of abnormal aluminum electrolysis cell condition has long been a challenging industrial issue due to its inherent complexity in analyzing based on multi-source knowledge. In addition, accur...Root cause analysis （RCA） of abnormal aluminum electrolysis cell condition has long been a challenging industrial issue due to its inherent complexity in analyzing based on multi-source knowledge. In addition, accurate RCA of abnormal aluminum electrolysis cell condition is the precondition of improving current efficiency. RCA of abnormal condition is a complex work of multi-source knowledge fusion, which is difficult to ensure the RCA accuracy of abnormal cell condition because of dwindling and frequent flow of experienced technicians. In view of this, a method based on Fuzzy- Bayesian network to construct multi-source knowledge solidification reasoning model is proposed. The method can effectively fuse and solidify the knowledge, which is used to analyze the cause of abnormal condition by technicians providing a clear and intuitive framework to this complex task, and also achieve the result of root cause automatically. The proposed method was verified under 20 sets of abnormal cell conditions, and implements root cause analysis by finding the abnormal state of root node, which has a maximum posterior probability by Bayesian diagnosis reasoning. The accuracy of the test results is up to 95%, which shows that the knowledge reasoning feasibility for RCA of aluminum electrolysis cell.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
基金supported by the Science and Technology Fund Project of Guizhou Health Commission(gzwkj2025-163)。
文摘Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth interviews with patients and families,anchored by Interactive Patient Par ticipation Theory,to analyze 4 high-severity adverse drug events(ADE)cases.Cases were purposively sampled from 8 communities in China's National Adverse Event Monitor Center(2018-2023).Semi-structured interviews explored patient perspectives,with data analyzed via thematic coding and triangulation against clinical records.Results:Five interconnected themes emerged:(1)erosion of trust,(2)communication breakdowns,(3)information asymmetry,(4)environmental inadequacies,and(5)technological alienation.Notably,75% of participants had≤high school education,and 50% used≥7 medications daily,compounding ADE risks.Conclusions:We considered elements mentioned by theory,exploring trust,communication,information,and suppor t as the root causes.In addition,we added“adaptability to new technology”as an impor tant and necessary component.It is impor tant and necessary to analyze typical adverse drug events from the perspectives of patients.
基金supported in part by the National Key R&D Program of China under Grant No.2024YFE0200504NSFC key international joint project under Grant No.62120106007Interdisciplinary Research Program of HUST under Grant No.2024JCYJ022.
文摘Fiber-to-the-Room(FTTR)has emerged as the core architecture for next-generation home and enterprise networks,offering gigabitlevel bandwidth and seamless wireless coverage.However,the complex multi-device topology of FTTR networks presents significant chal⁃lenges in identifying sources of network performance degradation and conducting accurate root cause analysis.Conventional approaches often fail to deliver efficient and precise operational improvements.To address this issue,this paper proposes a Transformer-based multi-task learn⁃ing model designed for automated root cause analysis in FTTR environments.The model integrates multidimensional time-series data col⁃lected from access points(APs),enabling the simultaneous detection of APs experiencing performance degradation and the classification of underlying root causes,such as weak signal coverage,network congestion,and signal interference.To facilitate model training and evaluation,a multi-label dataset is generated using a discrete-event simulation platform implemented in MATLAB.Experimental results demonstrate that the proposed Transformer-based multi-task learning model achieves a root cause classification accuracy of 96.75%,significantly outperform⁃ing baseline models including Long Short-Term Memory(LSTM),Gated Recurrent Unit(GRU),Random Forest,and eXtreme Gradient Boost⁃ing(XGBoost).This approach enables the rapid identification of performance degradation causes in FTTR networks,offering actionable in⁃sights for network optimization,reduced operational costs,and enhanced user experience.
基金supported by ZTE Industry-University-Institute Coopera⁃tion Funds under Grant No.HC-CN-20221123003.
文摘In recent years,microservice architecture has gained increasing popularity.However,due to the complex and dynamically chang⁃ing nature of microservice systems,failure detection has become more challenging.Traditional root cause analysis methods mostly rely on a single modality of data,which is insufficient to cover all failure information.Existing multimodal methods require collecting high-quality la⁃beled samples and often face challenges in classifying unknown failure categories.To address these challenges,this paper proposes a root cause analysis framework based on a masked graph autoencoder(GAE).The main process involves feature extraction,feature dimensionality reduction based on GAE,and online clustering combined with expert input.The method is experimentally evaluated on two public datasets and compared with two baseline methods,demonstrating significant advantages even with 16%labeled samples.
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 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With the continuous development of transportation, the subway has become a very important means of transportation for people to travel and an important part of reducing road traffic pressure. However, the subway has a large traffic volume and a high density in the process of operation. If a traffic accident occurs, it will cause very serious consequences. Therefore, we need to make a scientific and reasonable analysis of the overall factors of the subway mechanical and electrical equipment accident, and take targeted and effective measures to make timely and effective decisions, to prevent the occurrence of subway operation accidents, to ensure the safety of people's lives and property, and to ensure that national interests are not lost.
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Root cause analysis （RCA） of abnormal aluminum electrolysis cell condition has long been a challenging industrial issue due to its inherent complexity in analyzing based on multi-source knowledge. In addition, accurate RCA of abnormal aluminum electrolysis cell condition is the precondition of improving current efficiency. RCA of abnormal condition is a complex work of multi-source knowledge fusion, which is difficult to ensure the RCA accuracy of abnormal cell condition because of dwindling and frequent flow of experienced technicians. In view of this, a method based on Fuzzy- Bayesian network to construct multi-source knowledge solidification reasoning model is proposed. The method can effectively fuse and solidify the knowledge, which is used to analyze the cause of abnormal condition by technicians providing a clear and intuitive framework to this complex task, and also achieve the result of root cause automatically. The proposed method was verified under 20 sets of abnormal cell conditions, and implements root cause analysis by finding the abnormal state of root node, which has a maximum posterior probability by Bayesian diagnosis reasoning. The accuracy of the test results is up to 95%, which shows that the knowledge reasoning feasibility for RCA of aluminum electrolysis cell.
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.
