0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,...0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,87.45°E,with a depth of~10 km.展开更多
On 18 December 2023,a MS 6.2 earthquake struck the Jishishan area in Northwest China,located at the border of the Qinghai-Tibet and Loess Plateau.The earthquake triggered shallow loess landslides,small rock failures,a...On 18 December 2023,a MS 6.2 earthquake struck the Jishishan area in Northwest China,located at the border of the Qinghai-Tibet and Loess Plateau.The earthquake triggered shallow loess landslides,small rock failures,and soil cracks,mainly along hilly gullies and cut slopes at the edges of terraced fields.A rare large-scale flowslide also occurred in irrigated farmland.These seismic landslides and collapses blocked roads,buried farmland,damaged houses,and resulted in many casualties.Field investigations revealed that these geological hazards were concentrated around cultivated land.Consequently,cultivated land was introduced as an engineering geological zoning factor into the seismic geological hazard risk assessment for Jishishan area.The Newmark cumulative displacement model was refined by incorporating lithological uncertainties via the Monte Carlo method.Comparative analysis of coseismic geohazards with and without considering cultivated land suggests that,in loess-covered areas with cultivation activities,the consideration of the disturbed characteristics of soils provides a more accurate probabilistic risk assessment of seismic geohazards.Human cultivation and irrigation activities affect the physical properties of surface soil,the terraced fields around earthquake prone areas have a risk of earthquake-induced geological hazards.This study may offer valuable insights for hazard prevention and mitigation in high fortification intensity loess covered areas.展开更多
0 INTRODUCTION Due to the rapid population growth and the accelerated urbanization process,the contradiction between the demand for expanding ground space and the limited available land scale is becoming increasingly ...0 INTRODUCTION Due to the rapid population growth and the accelerated urbanization process,the contradiction between the demand for expanding ground space and the limited available land scale is becoming increasingly prominent.China has implemented and completed several largescale land infilling and excavation projects(Figure 1),which have become the main way to increase land resources and expand construction land.展开更多
INTRODUCTION Occupational safety and health (OSH) is generally the anticipation, recognition, evaluation, and control of hazards arising in or from the workplace. The study sought to assess and evaluate occupational h...INTRODUCTION Occupational safety and health (OSH) is generally the anticipation, recognition, evaluation, and control of hazards arising in or from the workplace. The study sought to assess and evaluate occupational health and safety hazards experienced among health workers in the Bono region of Ghana. METHODOLOGY The study was descriptive cross-sectional quantitative study. Data was from two hundred (200) health workers and was analyzed using the binary logistic regression analysis. RESULTS The findings from the study show that risk factors associated with biological hazards were clinical staff [OR = 2.487 (1.146 - 5.397), p = 0.021], poor maintenance of hospital items [OR = 0.446 (0.240 - 0.831), p = 0.011], assault (verbal) abuse [OR = 2.581 (1.317 - 5.059), p = 0.006] and extreme pressure from work [OR = 2.975 (1.519 - 5.829), p = 0.001]. Non-biological hazards were associated with being single [OR = 0.499 (0.263 - 0.947), p = 0.034], being verbally assaulted [OR = 3.581 (1.865 - 6.876), p CONCLUSION Risk factors related with biological hazards include poor maintenance of hospital items and extreme pressure from work whereas non-biological hazards were associated with being single, being verbally assaulted. Clinical healthcare providers are more vulnerable to occupational health and safety hazards. The study recommends the provision of strategic policies to promote and protect the workers’ health based on the development of the epidemiological profile of health, needs to be readjusted and strengthened.展开更多
The fragile and intricate geological environment of the Qinghai-Tibet Plateau gives rise to numerous precarious rocks along the riverbanks,posing significant risks for the upcoming construction of hydropower stations....The fragile and intricate geological environment of the Qinghai-Tibet Plateau gives rise to numerous precarious rocks along the riverbanks,posing significant risks for the upcoming construction of hydropower stations.In order to identify potential rockfalls that could endanger the Zixia hydropower project,a comprehensive analysis employing various methods was conducted to investigate the kinematic characteristics and dynamic fragmentation of such precarious rocks.Initially,UAV oblique photography and field survey were used to create a digital elevation model with a resolution of 0.25 m and map the spatial distribution of precarious rocks.Subsequently,the development characteristics of joints within rock masses were analyzed through an adit investigation.Following these preliminary steps,a transportation simulation utilizing RocPro3D,considering stochastic initiation orientation,was employed to predict the trajectories of 18 precarious rocks.As a result,two hazardous rocks that pose a direct threat to the cofferdam were identified.Finally,considering the influence of internal structure planes,a discrete element method was applied for accurately simulating the kinematic characteristics and dynamic fragmentation of these hazardous rocks.The findings underscore several key observations:(1)Slopeparallel structure planes within these hazardous rocks play a pivotal role in both the progressive failure during initiation and dynamic fragmentation during transportation;(2)Hazardous rocksⅢ-1 andⅣ-1 would pose a direct threat to the cofferdam.Notably,block b4 from hazardous rockⅢ-1,could potentially impact the cofferdam with an energy of 4598.65 kJ and an impact force of 3007.5 kN;and(3)Continuous collisions encountered during transportation facilitate the disintegration of rock masses along structure planes and generate substantial high-velocity fragments.Finally,to cope with the impact risk of collapsing blocks,a reinforced retaining wall as the mitigation measure is recommended.展开更多
In this study,avalanches in the Aerxiangou section of the Duku Expressway in the Tianshan Mountain area of Xinjiang were taken as the research object,and 92 avalanches were accurately identified through onsite researc...In this study,avalanches in the Aerxiangou section of the Duku Expressway in the Tianshan Mountain area of Xinjiang were taken as the research object,and 92 avalanches were accurately identified through onsite research.A high-resolution three-dimensional model was established by collecting images from unmanned aerial vehicles for an in-depth understanding of the avalanche danger of the region,according to the sample set selection of different uses of machine learning support vector machines to establish the S1-RBFKSVM,S1-PKSVM,S2-RBFKSVM,and S2-PKSVM avalanche susceptibility coupling models.On the basis of the avalanche point susceptibility,the impact velocity,impact force,avalanche volume,and throw distance constitute the hazard evaluation system.The study results revealed that slopes in the range of 26.6°–46.9°are more prone to avalanches,and sample set 2 improved the accuracy by approximately 30%compared with sample set 1 trained in the avalanche susceptibility model.Principal component analysis revealed a total of 16 high-risk avalanches,which were distributed mainly on the southern side of the route.This study provides data support for avalanche simulations as well as early warning and prevention and provides theoretical and methodological guidance for the construction and operation of the Duku Expressway.展开更多
Penaeus vannamei, known as the whiteleg shrimp, holds significant economic importance in aquaculture. The intensive culture of P. vannamei poses substantial environmental risks, particularly in fragile ecosystems like...Penaeus vannamei, known as the whiteleg shrimp, holds significant economic importance in aquaculture. The intensive culture of P. vannamei poses substantial environmental risks, particularly in fragile ecosystems like estuarine mangroves. Although there is a consensus on the pollution and harmful effects of microplastics(MPs), study on the pollution and potential risks posed by P. vannamei in estuary mangroves remains scarce. Therefore, the extent of microplastic pollution was evaluated and the correlation between the properties of MPs and the potential risks they pose to P. vannamei was examined.The average MP abundance in P. vannamei from Jiulong River estuary was determined to be 0.46±0.03 n/g in five different polymers, i.e., polypropylene(PP), polyethylene(PE), polystyrene(PS), polyethylene terephthalate(PET), and polyvinyl chloride resin(PVC). The total percentage of PS, PE, and PET polymers was the greatest(73.85%), where PET and PP(26.16%) were highly correlated in size and shape. Small MPs(1-200 μm) come in irregular particles, fragments, films, and large-sized MPs(200-1 000 μm) were mainly foam-shaped. The hazard risk level of MPs in P. vannamei from Jiulong River estuary reached grade Ⅲ, and the overall hazard risk index(H) value was 593.66. Among all samples,PVC polymer accounted for the lowest proportion(5.52%), but the H value was as high as 582.42, which contributed 98.11% to the overall hazard risk index. Regardless of global or Chinese, the microplastic pollution of P. vannamei in the estuary is at a moderate level. The protocol for MPs characteristics and correlation in seafood should be the basis for the risk assessment framework. Further studies are needed to evaluate how the exposure to MPs poses a risk for human health.展开更多
This study addresses gaps in aftershock prediction research by proposing an interpretable hybrid machine learning model that leverages multi-source data.The model overcomes challenges related to the selection of influ...This study addresses gaps in aftershock prediction research by proposing an interpretable hybrid machine learning model that leverages multi-source data.The model overcomes challenges related to the selection of influencing factors,model types,prediction result visualization,and decision mechanism interpretability.It integrates mainshock factors,geological features,site characteristics,and terrain conditions using geospatial information system(GIS)technology.By employing the stacking algorithm to optimize and combine XGBoost and LightGBM models,the proposed model significantly improves the prediction performance.Visualization through aftershock hazard mapping offers a robust tool for aftershock warning.The Shapley additive explanations(SHAP)model is used to explain the decision-making process from both global and local perspectives.Results show that,compared to the optimized XGBoost-CMA_ES and LightGBM-CMA_ES hybrid models,the stacking model achieves area under the curve(AUC)increases of 7.71%and 5.72% on the test set,respectively,with a maximum prediction accuracy of 0.9344.The hazard zoning map identifies high-risk areas mainly around fault lines and near the epicenter.As hazard levels rise,the proportion and density of aftershocks in these areas increase.The SHAP model results highlight the distance to fault as the most critical factor.The study integrates local explanations with on-site investigations,effectively visualizing the contributions of different factors to aftershocks.This research provides new tools and methods for enhancing aftershock warning and response.展开更多
Background: Healthcare workers are challenged by an imposing group of occupational hazards. These hazards include exposure to biological and non-biological hazards like ionizing radiation, stress, injury, infectious a...Background: Healthcare workers are challenged by an imposing group of occupational hazards. These hazards include exposure to biological and non-biological hazards like ionizing radiation, stress, injury, infectious agents, and chemicals. The aim of this study was to assess common occupational hazards among health workers at the Department of Health Services (DHS), Federal University of Technology, Owerri. Methods: A hospital-based cross-sectional study design was employed for the study, and a self-administered questionnaire was used for data collection. The SPSS Version 22.0 software was used for the analysis of the descriptive statistics obtained from the study. This study included both clinical and non-clinical health workers. A purposive sampling technique was used in recruiting a total of 94 respondents who participated in the study from September 2020 to April 2021. Results: A total of 94 respondents who participated in the study and among the participants, 33.3% (31) of the respondents were aged 31 - 40 years, and the majority of the health workers, 43.6% (41) had stayed between 1 - 5 years. Also, 92.6% (87) of the health workers have heard of occupational hazards. The study showed that 84.0% (79) of health workers had good knowledge of common occupational hazards. Biological hazards among health workers are 47.9% (45) cuts and wounds, 29.8% (28) direct contact with contaminated specimens/hazardous materials, and 26.6% (26) sharp related injuries, while for non-biological hazards, 44.7% (42) have slipped, tripped or fallen, and 35.1% (33) have been stressed. Common safety measures include 86.2% (81) washing their hands regularly;78.7% (74) using hand gloves;and 85.1% (80) agreeing they use face masks. Conclusion: Despite good knowledge of occupational hazards, participants at DHS were faced with certain hazards. It is recommended that the university, government, and policymakers revise and implement actions to provide health workers at DHS with equipment to encourage safety in work activity.展开更多
Since the 21st century, the world is facing increasingly severe disaster problems, which greatly affect the development of human economy. As one of the natural disasters, the study of marine geological disasters is be...Since the 21st century, the world is facing increasingly severe disaster problems, which greatly affect the development of human economy. As one of the natural disasters, the study of marine geological disasters is becoming a research hotspot. From the perspective of disaster mechanism, this paper reviews the classification methods of marine geological disasters from 1980 to now, and discusses the genetic mechanism of typical marine geological disasters on the continental margin, which provides scientific basis for the construction of marine engineering.展开更多
Rockburst hazard in mining industry all over the world is one of the most severe hazards. It is becoming increasingly common because of the ever-growing depths of mining operations accompanied by the increasing streng...Rockburst hazard in mining industry all over the world is one of the most severe hazards. It is becoming increasingly common because of the ever-growing depths of mining operations accompanied by the increasing strength of rocks. One of the most difficult issues is to predict this hazard before the mining operations, whether geophysical investigations have been conducted or not. Polish experience in this field shows that in such cases an effective solution can be the geomechanical method. Therefore, extensive studies on rockburst hazard should focus on three main aspects:(1) rock mass and rock(and coal)predisposition to rockburst–laboratory tests and empirical analyses based on lithology,(2) identification of the potential places with stress and elastic energy concentration in the rock mass within the area planned for exploitation, and(3) the assessment of the impact of mining tremors on the surface. This preliminary geomechanical analysis assesses the propensity of the rock mass to dynamic breakage and provides quantitatively the level of rockburst hazard. The paper presents Polish experience in rockburst hazard assessment with the use of geomechanical method, as well as some solutions and examples of such analyses.展开更多
Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide ...Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide over the slip surface at different heights of the model slopes, as well as taking the whole slope to identify its deformation and failure processes. The results show that the rainfall duration corresponding to the initiation of the debris landslide and is exponentially related to rainfall intensity. Corresponding to the three intervals of the rainfall intensity, there are three types of slope failure modes:(1) the small-slump failure at the leading edge of the slope;(2) the block-slump failure but sometimes there are large blocks sliding down;and(3) the bulk failure but sometimes there is the block-slump failure. Based on the total rainfall-lasting time and the associated proportion of failed mass volume, the early warning of debris landslide can be classified into five grades, i.e., red, orange to red, orange, yellow to orange and yellow, which correspond to the five slope failure modes, respectively.展开更多
The complicated geological conditions and geological hazards are challenging problems during tunnel construction,which will cause great losses of life and property.Therefore,reliable prediction of geological defective...The complicated geological conditions and geological hazards are challenging problems during tunnel construction,which will cause great losses of life and property.Therefore,reliable prediction of geological defective features,such as faults,karst caves and groundwater,has important practical significances and theoretical values.In this paper,we presented the criteria for detecting typical geological anomalies using the tunnel seismic prediction（TSP） method.The ground penetrating radar（GPR） signal response to water-bearing structures was used for theoretical derivations.And the 3D tomography of the transient electromagnetic method（TEM） was used to develop an equivalent conductance method.Based on the improvement of a single prediction technique,we developed a technical system for reliable prediction of geological defective features by analyzing the advantages and disadvantages of all prediction methods.The procedure of the application of this system was introduced in detail.For prediction,the selection of prediction methods is an important and challenging work.The analytic hierarchy process（AHP） was developed for prediction optimization.We applied the newly developed prediction system to several important projects in China,including Hurongxi highway,Jinping II hydropower station,and Kiaochow Bay subsea tunnel.The case studies show that the geological defective features can be successfully detected with good precision and efficiency,and the prediction system is proved to be an effective means to minimize the risks of geological hazards during tunnel construction.展开更多
Gas outbursts from "three-soft" coal seams (soft roof,soft floor and soft coal) constitute a very serious prob-lem in the Ludian gliding structure area in western Henan. By means of theories and methods of g...Gas outbursts from "three-soft" coal seams (soft roof,soft floor and soft coal) constitute a very serious prob-lem in the Ludian gliding structure area in western Henan. By means of theories and methods of gas geology,structural geology,coal petrology and rock tests,we have discussed the effect of control of several physical properties of soft roof on gas preservation and proposed a new method of forecasting gas geological hazards under open structural conditions. The result shows that the areas with type Ⅲ or Ⅳ soft roofs are the most dangerous areas where gas outburst most likely can take place. Therefore,countermeasures should be taken in these areas to prevent gas outbursts.展开更多
Oil and gas pipelines are of great importance in China,and pipeline security problems pose a serious threat to society and the environment.Pipeline safety has therefore become an integral part of the entire national e...Oil and gas pipelines are of great importance in China,and pipeline security problems pose a serious threat to society and the environment.Pipeline safety has therefore become an integral part of the entire national economy.Landslides are the most harmful type of pipeline accident,and have directed increasing public attention to safety issues.Although some useful results have been obtained in the investigation and prevention of pipeline-landslide hazards,there remains a need for effective monitoring and early warning methods,especially when the complexity of pipeline-landslides is considered.Because oil and gas pipeline-landslides typically occur in the superficial soil layers,monitoring instruments must be easy to install and must cause minimal disturbance to the surrounding soil and pipeline.To address the particular characteristics of pipelinelandslides,we developed a multi-parameter integrated monitoring system called disaster reduction stick equipment.In this paper,we detail this monitoring and early warning system for pipeline-landslide hazards based on an on-site monitoring network and early warning algorithms.The functionality of our system was verified by its successful application to the Chongqing Loujiazhuang pipeline-landslide in China.The results presented here provide guidelines for the monitoring,early warning,and prevention of pipeline geological hazards.展开更多
Coping with extreme climate events and its related climatic disasters caused by climate change has become a global issue and drew wide attention from scientists, policy-makers and public. This paper calculated the exp...Coping with extreme climate events and its related climatic disasters caused by climate change has become a global issue and drew wide attention from scientists, policy-makers and public. This paper calculated the expected annual multiple climatic hazards intensity index based on the results of nine climatic hazards including tropical cyclone, flood, landslide, storm surge, sand-dust storm, drought, heat wave, cold wave and wildfire. Then a vulnerability model involving the coping capacity indicator with mortality rate, affected population rate and GDP loss rate, was developed to estimate the expected annual affected population, mortality and GDP loss risks. The results showed that： countries with the highest risks are also the countries with large population or GDP. To substantially reduce the global total climatic hazards risks, these countries should reduce the exposure and improving the governance of integrated climatic risk; Without considering the total exposure, countries with the high mortality rate, affected population rate or GDP loss rate, which also have higher or lower coping capacity, such as the Philippines, Bangladesh and Vietnam, are the hotspots of the planning and strategy making for the climatic disaster risk reduction and should focus on promoting the coping capacity.展开更多
Conducting a hazard assessment for secondary mountain hazards is the technical basis for reconstructing destroyed highways and for disaster prevention.It is necessary to consider the role and influence of structural e...Conducting a hazard assessment for secondary mountain hazards is the technical basis for reconstructing destroyed highways and for disaster prevention.It is necessary to consider the role and influence of structural engineering measures as an important assessment factor.In this study,based on six substantial field investigations conducted between July 2008 and July 2012,a 2 km wide zone along both sides of the Dujiangyan Wenchuan(Du Wen) Highway was selected as the study area.Microgeomorphic units and small watersheds in the study area were extracted with GIS software and used as basic assessment units.Through field investigations,remote sensing surveys and experimental analysis,a structural engineering effectiveness assessment was conducted using the technique of principal component analysis.The results showed the following:1) A total of 491 collapses,12 landslides,32 slope debris flows and 17 gully debris flows were scatted across the study area.The total overall areal density of all mountain hazards was 25.7%.The distribution of secondary hazards was influenced mainly by seismic intensity,active fault zones,lithology,slope and altitude.More than 70% of secondary hazards occurred in zones with a seismic intensity of XI,a distance to the fault zone of between 0 and 25 km,a slope between 25° and 50°,and an altitude of between 1,000 m and 1,800 m.2) Different structural engineering measures play different roles and effects in controlling different types and scales of secondary mountain hazards.3) With a secondary mountain hazard area of 128.1 km2and an areal density of 34.9%,medium,high and very high hazard zones accounted for 74% of the study area and were located on the high,steep slopes along both sides of the highway.The low hazard zone was located mainly in the valley floor,on gentle slope platforms and at locations 1.5 km away from the highway the hazard area was 45 km2and the areal density was 3.3%.4) The methodology for hazard assessment of secondary mountain hazards,which is based on five factors,solves such key technical problems as the selection of assessment units,multi-source data fusion,and the weight calculation for each assessment index.This study provides a new and more effective method for assessing secondary mountain hazards along highways,and the proposed models fit well with validation data and field observations.The findings were applied to reconstruction and disaster mitigation in the case of the Du Wen Highway and proved to be feasible.展开更多
As a discipline,the science of natural hazards and disaster risk aims to explain the spatial-temporal pattern,process and mechanism,emergency response and risk mitigation of natural hazards,which requires a multidisci...As a discipline,the science of natural hazards and disaster risk aims to explain the spatial-temporal pattern,process and mechanism,emergency response and risk mitigation of natural hazards,which requires a multidisci-plinary and interdisciplinary approach.With the support of Natural Science Finance of China(NSFC)and Chinese Academy of Sciences(CAS),in-depth research and systematic analysis on natural hazards and disaster risk were conducted.In this paper,the state of the art in research on natural hazards is summarized from seven aspects:formation process,mechanism and dynamic of natural hazards,disaster risk assessment,forecast,monitoring and early warning,disaster mitigation,emergency treatment and rescue,risk management and post-disaster re-construction.The trends within the natural hazards and disaster risk as a discipline were identified,along with existing shortcomings and significant gaps that need to be addressed.This paper highlighted:1)the scientific challenges including the frontier scientific issues and technological gaps on natural hazards and disaster risk dis-cipline from 2025 to 2035 in China,and 2)the proposal to develop a systemic and holistic natural hazards and disaster risk discipline.展开更多
Tibet is one of the areas with most serious geological hazards in China, and the distribution of disasters has obvious local charac teristics. Tibet can be classified as three parts through zoning the danger degree, t...Tibet is one of the areas with most serious geological hazards in China, and the distribution of disasters has obvious local charac teristics. Tibet can be classified as three parts through zoning the danger degree, the mountain canyon high danger zone of east and southeast Tibet, the plateau mountain lake basin and valley middle danger zone of south Tibet, and the Plateau Mountain lake basin low danger zone of south Tibet. This paper takes the debris flow, collapse, landslide as the key points to analyze the distribution characteristics of geological hazards, and analyze the factors which influence the distribution of geological hazards, such as terrain landform, formation lithology, geologic structure pattern, precipitation, earthquake, human activity and so on. finally, as a conclusion., in whole Tibet, the geological hazards are more in southeast than in northwest, more in mountainous area which in the edge of plateau and river valley than in the interior of plateau and lake basin. And most hazards distribute in the regions where human activity is stronger than in other regions, for example towns or strips along the highway.展开更多
Supported by the spatial analysis feature of geographic information science and assessment model of regional debris flows, hazards degrees of the debris flows in the Upper Yangtze River Watershed （UYRW） are divided ...Supported by the spatial analysis feature of geographic information science and assessment model of regional debris flows, hazards degrees of the debris flows in the Upper Yangtze River Watershed （UYRW） are divided into five grades based on grid cell. The area of no danger, light danger, medium danger, severe danger and extreme severe danger regions respectively are 278 000, 288 000, 217 000, 127 000, 15 000 km^2. Furthermore, the counties in the UYRW are classified into four classes based on the hazards degrees in each county. The number of severe danger, medium danger, light danger and no danger counties respectively are 49, 82, 77 and 105. The assessment results will be provided for the hazards forecasting and mitigation in the UYRW and ongoing regionalization of Main Function Regions in China as data and technique framework.展开更多
基金funded by the National Key R&D Program of China(No.2020YFC150071)partly supported by the Shaanxi Province Geoscience Big Data and Geohazard Prevention Innovation Team(2022)and the Research Funds for the Interdisciplinary Projects,CHU(No.300104240914)。
文摘0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,87.45°E,with a depth of~10 km.
基金funded by the Basic Scientific Research Fund,Science and Technology Innovation Base of Lanzhou,Institute of Earthquake Forecasting,China Earthquake Administration(Grants No.2020IESLZ03 and 2015IESLZ05)the National Key R&D program of China(Grant No.2017YFC1500906)
文摘On 18 December 2023,a MS 6.2 earthquake struck the Jishishan area in Northwest China,located at the border of the Qinghai-Tibet and Loess Plateau.The earthquake triggered shallow loess landslides,small rock failures,and soil cracks,mainly along hilly gullies and cut slopes at the edges of terraced fields.A rare large-scale flowslide also occurred in irrigated farmland.These seismic landslides and collapses blocked roads,buried farmland,damaged houses,and resulted in many casualties.Field investigations revealed that these geological hazards were concentrated around cultivated land.Consequently,cultivated land was introduced as an engineering geological zoning factor into the seismic geological hazard risk assessment for Jishishan area.The Newmark cumulative displacement model was refined by incorporating lithological uncertainties via the Monte Carlo method.Comparative analysis of coseismic geohazards with and without considering cultivated land suggests that,in loess-covered areas with cultivation activities,the consideration of the disturbed characteristics of soils provides a more accurate probabilistic risk assessment of seismic geohazards.Human cultivation and irrigation activities affect the physical properties of surface soil,the terraced fields around earthquake prone areas have a risk of earthquake-induced geological hazards.This study may offer valuable insights for hazard prevention and mitigation in high fortification intensity loess covered areas.
基金funded by the Key Research and Development Program of Shaanxi Province(No.2024SFYBXM-669)the National Natural Science Foundation of China(No.42271078)。
文摘0 INTRODUCTION Due to the rapid population growth and the accelerated urbanization process,the contradiction between the demand for expanding ground space and the limited available land scale is becoming increasingly prominent.China has implemented and completed several largescale land infilling and excavation projects(Figure 1),which have become the main way to increase land resources and expand construction land.
文摘INTRODUCTION Occupational safety and health (OSH) is generally the anticipation, recognition, evaluation, and control of hazards arising in or from the workplace. The study sought to assess and evaluate occupational health and safety hazards experienced among health workers in the Bono region of Ghana. METHODOLOGY The study was descriptive cross-sectional quantitative study. Data was from two hundred (200) health workers and was analyzed using the binary logistic regression analysis. RESULTS The findings from the study show that risk factors associated with biological hazards were clinical staff [OR = 2.487 (1.146 - 5.397), p = 0.021], poor maintenance of hospital items [OR = 0.446 (0.240 - 0.831), p = 0.011], assault (verbal) abuse [OR = 2.581 (1.317 - 5.059), p = 0.006] and extreme pressure from work [OR = 2.975 (1.519 - 5.829), p = 0.001]. Non-biological hazards were associated with being single [OR = 0.499 (0.263 - 0.947), p = 0.034], being verbally assaulted [OR = 3.581 (1.865 - 6.876), p CONCLUSION Risk factors related with biological hazards include poor maintenance of hospital items and extreme pressure from work whereas non-biological hazards were associated with being single, being verbally assaulted. Clinical healthcare providers are more vulnerable to occupational health and safety hazards. The study recommends the provision of strategic policies to promote and protect the workers’ health based on the development of the epidemiological profile of health, needs to be readjusted and strengthened.
基金gratefully acknowledge support from the National Key Research and Development Program of China(Grant No.2022YFC3005704)the National Natural Science Foundation of China(Grant No.42277143)the Sichuan Province natural Science Foundation project(Grant No.2024NSFSC0100).
文摘The fragile and intricate geological environment of the Qinghai-Tibet Plateau gives rise to numerous precarious rocks along the riverbanks,posing significant risks for the upcoming construction of hydropower stations.In order to identify potential rockfalls that could endanger the Zixia hydropower project,a comprehensive analysis employing various methods was conducted to investigate the kinematic characteristics and dynamic fragmentation of such precarious rocks.Initially,UAV oblique photography and field survey were used to create a digital elevation model with a resolution of 0.25 m and map the spatial distribution of precarious rocks.Subsequently,the development characteristics of joints within rock masses were analyzed through an adit investigation.Following these preliminary steps,a transportation simulation utilizing RocPro3D,considering stochastic initiation orientation,was employed to predict the trajectories of 18 precarious rocks.As a result,two hazardous rocks that pose a direct threat to the cofferdam were identified.Finally,considering the influence of internal structure planes,a discrete element method was applied for accurately simulating the kinematic characteristics and dynamic fragmentation of these hazardous rocks.The findings underscore several key observations:(1)Slopeparallel structure planes within these hazardous rocks play a pivotal role in both the progressive failure during initiation and dynamic fragmentation during transportation;(2)Hazardous rocksⅢ-1 andⅣ-1 would pose a direct threat to the cofferdam.Notably,block b4 from hazardous rockⅢ-1,could potentially impact the cofferdam with an energy of 4598.65 kJ and an impact force of 3007.5 kN;and(3)Continuous collisions encountered during transportation facilitate the disintegration of rock masses along structure planes and generate substantial high-velocity fragments.Finally,to cope with the impact risk of collapsing blocks,a reinforced retaining wall as the mitigation measure is recommended.
基金funded by the Key Science and Technology Project of Transportation Industry(2022-ZD6-090)Xinjiang Transportation Science and Technology Project(2022-ZD-006)+1 种基金Xinjiang Transportation Investment 2021"Unveiling the List of Commander-in-Chief"Science and Technology Project(ZKXFWCG2022060004)the Science and Technology Research and Development Project(KY2022021501)of Xinjiang Transportation Design Institute。
文摘In this study,avalanches in the Aerxiangou section of the Duku Expressway in the Tianshan Mountain area of Xinjiang were taken as the research object,and 92 avalanches were accurately identified through onsite research.A high-resolution three-dimensional model was established by collecting images from unmanned aerial vehicles for an in-depth understanding of the avalanche danger of the region,according to the sample set selection of different uses of machine learning support vector machines to establish the S1-RBFKSVM,S1-PKSVM,S2-RBFKSVM,and S2-PKSVM avalanche susceptibility coupling models.On the basis of the avalanche point susceptibility,the impact velocity,impact force,avalanche volume,and throw distance constitute the hazard evaluation system.The study results revealed that slopes in the range of 26.6°–46.9°are more prone to avalanches,and sample set 2 improved the accuracy by approximately 30%compared with sample set 1 trained in the avalanche susceptibility model.Principal component analysis revealed a total of 16 high-risk avalanches,which were distributed mainly on the southern side of the route.This study provides data support for avalanche simulations as well as early warning and prevention and provides theoretical and methodological guidance for the construction and operation of the Duku Expressway.
基金Supported by the Natural Science Foundation of Xiamen (No. 3502Z20227322)the Natural Science Key Foundation of Fujian Province (No. 2020J02002)+1 种基金the Social Science Foundation of Fujian Province (No. FJ2024BF047)the Financial Research Projects of Fujian Province (No. 2024-48)。
文摘Penaeus vannamei, known as the whiteleg shrimp, holds significant economic importance in aquaculture. The intensive culture of P. vannamei poses substantial environmental risks, particularly in fragile ecosystems like estuarine mangroves. Although there is a consensus on the pollution and harmful effects of microplastics(MPs), study on the pollution and potential risks posed by P. vannamei in estuary mangroves remains scarce. Therefore, the extent of microplastic pollution was evaluated and the correlation between the properties of MPs and the potential risks they pose to P. vannamei was examined.The average MP abundance in P. vannamei from Jiulong River estuary was determined to be 0.46±0.03 n/g in five different polymers, i.e., polypropylene(PP), polyethylene(PE), polystyrene(PS), polyethylene terephthalate(PET), and polyvinyl chloride resin(PVC). The total percentage of PS, PE, and PET polymers was the greatest(73.85%), where PET and PP(26.16%) were highly correlated in size and shape. Small MPs(1-200 μm) come in irregular particles, fragments, films, and large-sized MPs(200-1 000 μm) were mainly foam-shaped. The hazard risk level of MPs in P. vannamei from Jiulong River estuary reached grade Ⅲ, and the overall hazard risk index(H) value was 593.66. Among all samples,PVC polymer accounted for the lowest proportion(5.52%), but the H value was as high as 582.42, which contributed 98.11% to the overall hazard risk index. Regardless of global or Chinese, the microplastic pollution of P. vannamei in the estuary is at a moderate level. The protocol for MPs characteristics and correlation in seafood should be the basis for the risk assessment framework. Further studies are needed to evaluate how the exposure to MPs poses a risk for human health.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFC3007203).
文摘This study addresses gaps in aftershock prediction research by proposing an interpretable hybrid machine learning model that leverages multi-source data.The model overcomes challenges related to the selection of influencing factors,model types,prediction result visualization,and decision mechanism interpretability.It integrates mainshock factors,geological features,site characteristics,and terrain conditions using geospatial information system(GIS)technology.By employing the stacking algorithm to optimize and combine XGBoost and LightGBM models,the proposed model significantly improves the prediction performance.Visualization through aftershock hazard mapping offers a robust tool for aftershock warning.The Shapley additive explanations(SHAP)model is used to explain the decision-making process from both global and local perspectives.Results show that,compared to the optimized XGBoost-CMA_ES and LightGBM-CMA_ES hybrid models,the stacking model achieves area under the curve(AUC)increases of 7.71%and 5.72% on the test set,respectively,with a maximum prediction accuracy of 0.9344.The hazard zoning map identifies high-risk areas mainly around fault lines and near the epicenter.As hazard levels rise,the proportion and density of aftershocks in these areas increase.The SHAP model results highlight the distance to fault as the most critical factor.The study integrates local explanations with on-site investigations,effectively visualizing the contributions of different factors to aftershocks.This research provides new tools and methods for enhancing aftershock warning and response.
文摘Background: Healthcare workers are challenged by an imposing group of occupational hazards. These hazards include exposure to biological and non-biological hazards like ionizing radiation, stress, injury, infectious agents, and chemicals. The aim of this study was to assess common occupational hazards among health workers at the Department of Health Services (DHS), Federal University of Technology, Owerri. Methods: A hospital-based cross-sectional study design was employed for the study, and a self-administered questionnaire was used for data collection. The SPSS Version 22.0 software was used for the analysis of the descriptive statistics obtained from the study. This study included both clinical and non-clinical health workers. A purposive sampling technique was used in recruiting a total of 94 respondents who participated in the study from September 2020 to April 2021. Results: A total of 94 respondents who participated in the study and among the participants, 33.3% (31) of the respondents were aged 31 - 40 years, and the majority of the health workers, 43.6% (41) had stayed between 1 - 5 years. Also, 92.6% (87) of the health workers have heard of occupational hazards. The study showed that 84.0% (79) of health workers had good knowledge of common occupational hazards. Biological hazards among health workers are 47.9% (45) cuts and wounds, 29.8% (28) direct contact with contaminated specimens/hazardous materials, and 26.6% (26) sharp related injuries, while for non-biological hazards, 44.7% (42) have slipped, tripped or fallen, and 35.1% (33) have been stressed. Common safety measures include 86.2% (81) washing their hands regularly;78.7% (74) using hand gloves;and 85.1% (80) agreeing they use face masks. Conclusion: Despite good knowledge of occupational hazards, participants at DHS were faced with certain hazards. It is recommended that the university, government, and policymakers revise and implement actions to provide health workers at DHS with equipment to encourage safety in work activity.
文摘Since the 21st century, the world is facing increasingly severe disaster problems, which greatly affect the development of human economy. As one of the natural disasters, the study of marine geological disasters is becoming a research hotspot. From the perspective of disaster mechanism, this paper reviews the classification methods of marine geological disasters from 1980 to now, and discusses the genetic mechanism of typical marine geological disasters on the continental margin, which provides scientific basis for the construction of marine engineering.
文摘Rockburst hazard in mining industry all over the world is one of the most severe hazards. It is becoming increasingly common because of the ever-growing depths of mining operations accompanied by the increasing strength of rocks. One of the most difficult issues is to predict this hazard before the mining operations, whether geophysical investigations have been conducted or not. Polish experience in this field shows that in such cases an effective solution can be the geomechanical method. Therefore, extensive studies on rockburst hazard should focus on three main aspects:(1) rock mass and rock(and coal)predisposition to rockburst–laboratory tests and empirical analyses based on lithology,(2) identification of the potential places with stress and elastic energy concentration in the rock mass within the area planned for exploitation, and(3) the assessment of the impact of mining tremors on the surface. This preliminary geomechanical analysis assesses the propensity of the rock mass to dynamic breakage and provides quantitatively the level of rockburst hazard. The paper presents Polish experience in rockburst hazard assessment with the use of geomechanical method, as well as some solutions and examples of such analyses.
基金This research is financially supported by the National Natural Science Foundation of China(Nos.41807274,41630640)the Sichuan Science and Technology Program(No.2019E0R2230230)the Scientific Foundation of the Chinese Academy of Sciences(No.KFJ-STS-QYZD-172)。
文摘Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide over the slip surface at different heights of the model slopes, as well as taking the whole slope to identify its deformation and failure processes. The results show that the rainfall duration corresponding to the initiation of the debris landslide and is exponentially related to rainfall intensity. Corresponding to the three intervals of the rainfall intensity, there are three types of slope failure modes:(1) the small-slump failure at the leading edge of the slope;(2) the block-slump failure but sometimes there are large blocks sliding down;and(3) the bulk failure but sometimes there is the block-slump failure. Based on the total rainfall-lasting time and the associated proportion of failed mass volume, the early warning of debris landslide can be classified into five grades, i.e., red, orange to red, orange, yellow to orange and yellow, which correspond to the five slope failure modes, respectively.
基金Supported by National Natural Science Foundation of China (50625927,50727904)the National Basic Research Program (973) of China (2007CB209407)Ministry of Communications’Scientific and Technological Program of Transportation Development in Western China(2009318000008)
文摘The complicated geological conditions and geological hazards are challenging problems during tunnel construction,which will cause great losses of life and property.Therefore,reliable prediction of geological defective features,such as faults,karst caves and groundwater,has important practical significances and theoretical values.In this paper,we presented the criteria for detecting typical geological anomalies using the tunnel seismic prediction（TSP） method.The ground penetrating radar（GPR） signal response to water-bearing structures was used for theoretical derivations.And the 3D tomography of the transient electromagnetic method（TEM） was used to develop an equivalent conductance method.Based on the improvement of a single prediction technique,we developed a technical system for reliable prediction of geological defective features by analyzing the advantages and disadvantages of all prediction methods.The procedure of the application of this system was introduced in detail.For prediction,the selection of prediction methods is an important and challenging work.The analytic hierarchy process（AHP） was developed for prediction optimization.We applied the newly developed prediction system to several important projects in China,including Hurongxi highway,Jinping II hydropower station,and Kiaochow Bay subsea tunnel.The case studies show that the geological defective features can be successfully detected with good precision and efficiency,and the prediction system is proved to be an effective means to minimize the risks of geological hazards during tunnel construction.
文摘Gas outbursts from "three-soft" coal seams (soft roof,soft floor and soft coal) constitute a very serious prob-lem in the Ludian gliding structure area in western Henan. By means of theories and methods of gas geology,structural geology,coal petrology and rock tests,we have discussed the effect of control of several physical properties of soft roof on gas preservation and proposed a new method of forecasting gas geological hazards under open structural conditions. The result shows that the areas with type Ⅲ or Ⅳ soft roofs are the most dangerous areas where gas outburst most likely can take place. Therefore,countermeasures should be taken in these areas to prevent gas outbursts.
基金financially supported by National Key R&D Program of China (No. 2018YFC1505201)National Natural Science Foundation of China (No. 41901008)+2 种基金Open Fund Project of Key Laboratory of Mountain Hazards and Surface Processes of the Chinese Academy of Sciencesthe Fundamental Research Funds for the Central Universities (Grant NO. 2682018CX05)financially supported by China Scholarship Council
文摘Oil and gas pipelines are of great importance in China,and pipeline security problems pose a serious threat to society and the environment.Pipeline safety has therefore become an integral part of the entire national economy.Landslides are the most harmful type of pipeline accident,and have directed increasing public attention to safety issues.Although some useful results have been obtained in the investigation and prevention of pipeline-landslide hazards,there remains a need for effective monitoring and early warning methods,especially when the complexity of pipeline-landslides is considered.Because oil and gas pipeline-landslides typically occur in the superficial soil layers,monitoring instruments must be easy to install and must cause minimal disturbance to the surrounding soil and pipeline.To address the particular characteristics of pipelinelandslides,we developed a multi-parameter integrated monitoring system called disaster reduction stick equipment.In this paper,we detail this monitoring and early warning system for pipeline-landslide hazards based on an on-site monitoring network and early warning algorithms.The functionality of our system was verified by its successful application to the Chongqing Loujiazhuang pipeline-landslide in China.The results presented here provide guidelines for the monitoring,early warning,and prevention of pipeline geological hazards.
基金The Innovative Research Group Project of National Natural Science Foundation of China,No.41321001The National Basic Research Program(973 Program),No.2012CB955404The Program for Introducing Talents of Disciplines to Universities funded by the Ministry of Education and State Administration of Foreign Experts Affairs,China,No.B08008
文摘Coping with extreme climate events and its related climatic disasters caused by climate change has become a global issue and drew wide attention from scientists, policy-makers and public. This paper calculated the expected annual multiple climatic hazards intensity index based on the results of nine climatic hazards including tropical cyclone, flood, landslide, storm surge, sand-dust storm, drought, heat wave, cold wave and wildfire. Then a vulnerability model involving the coping capacity indicator with mortality rate, affected population rate and GDP loss rate, was developed to estimate the expected annual affected population, mortality and GDP loss risks. The results showed that： countries with the highest risks are also the countries with large population or GDP. To substantially reduce the global total climatic hazards risks, these countries should reduce the exposure and improving the governance of integrated climatic risk; Without considering the total exposure, countries with the high mortality rate, affected population rate or GDP loss rate, which also have higher or lower coping capacity, such as the Philippines, Bangladesh and Vietnam, are the hotspots of the planning and strategy making for the climatic disaster risk reduction and should focus on promoting the coping capacity.
基金supported by the National Natural Science Foundation of China(Grant No.40901273)the Open Fund of Key Laboratory of Special Environment Road Engineering of Hunan Province(Changsha University of Science and Technology,Grant No.kfj120404)+1 种基金the Western China Communication Science and Technology Projection(Grant No.2008-318-221-56)the Graduate Innovation Foundation of Hunan University of Science and Technology(Grant No.S120033 and S120034)
文摘Conducting a hazard assessment for secondary mountain hazards is the technical basis for reconstructing destroyed highways and for disaster prevention.It is necessary to consider the role and influence of structural engineering measures as an important assessment factor.In this study,based on six substantial field investigations conducted between July 2008 and July 2012,a 2 km wide zone along both sides of the Dujiangyan Wenchuan(Du Wen) Highway was selected as the study area.Microgeomorphic units and small watersheds in the study area were extracted with GIS software and used as basic assessment units.Through field investigations,remote sensing surveys and experimental analysis,a structural engineering effectiveness assessment was conducted using the technique of principal component analysis.The results showed the following:1) A total of 491 collapses,12 landslides,32 slope debris flows and 17 gully debris flows were scatted across the study area.The total overall areal density of all mountain hazards was 25.7%.The distribution of secondary hazards was influenced mainly by seismic intensity,active fault zones,lithology,slope and altitude.More than 70% of secondary hazards occurred in zones with a seismic intensity of XI,a distance to the fault zone of between 0 and 25 km,a slope between 25° and 50°,and an altitude of between 1,000 m and 1,800 m.2) Different structural engineering measures play different roles and effects in controlling different types and scales of secondary mountain hazards.3) With a secondary mountain hazard area of 128.1 km2and an areal density of 34.9%,medium,high and very high hazard zones accounted for 74% of the study area and were located on the high,steep slopes along both sides of the highway.The low hazard zone was located mainly in the valley floor,on gentle slope platforms and at locations 1.5 km away from the highway the hazard area was 45 km2and the areal density was 3.3%.4) The methodology for hazard assessment of secondary mountain hazards,which is based on five factors,solves such key technical problems as the selection of assessment units,multi-source data fusion,and the weight calculation for each assessment index.This study provides a new and more effective method for assessing secondary mountain hazards along highways,and the proposed models fit well with validation data and field observations.The findings were applied to reconstruction and disaster mitigation in the case of the Du Wen Highway and proved to be feasible.
基金This work was supported by the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(Grant No.QYZDY-SSW-DQC006)the Major Program of National Natural Science Foundation of China(Grant No.41790432)+1 种基金the National Natural Science Foundation of China(Grant No.L1924041)Research Project on the Discipline Development Strategy of Academic Divisions of the Chinese Academy of Sciences(Grand No.XK2019DXC006).
文摘As a discipline,the science of natural hazards and disaster risk aims to explain the spatial-temporal pattern,process and mechanism,emergency response and risk mitigation of natural hazards,which requires a multidisci-plinary and interdisciplinary approach.With the support of Natural Science Finance of China(NSFC)and Chinese Academy of Sciences(CAS),in-depth research and systematic analysis on natural hazards and disaster risk were conducted.In this paper,the state of the art in research on natural hazards is summarized from seven aspects:formation process,mechanism and dynamic of natural hazards,disaster risk assessment,forecast,monitoring and early warning,disaster mitigation,emergency treatment and rescue,risk management and post-disaster re-construction.The trends within the natural hazards and disaster risk as a discipline were identified,along with existing shortcomings and significant gaps that need to be addressed.This paper highlighted:1)the scientific challenges including the frontier scientific issues and technological gaps on natural hazards and disaster risk dis-cipline from 2025 to 2035 in China,and 2)the proposal to develop a systemic and holistic natural hazards and disaster risk discipline.
文摘Tibet is one of the areas with most serious geological hazards in China, and the distribution of disasters has obvious local charac teristics. Tibet can be classified as three parts through zoning the danger degree, the mountain canyon high danger zone of east and southeast Tibet, the plateau mountain lake basin and valley middle danger zone of south Tibet, and the Plateau Mountain lake basin low danger zone of south Tibet. This paper takes the debris flow, collapse, landslide as the key points to analyze the distribution characteristics of geological hazards, and analyze the factors which influence the distribution of geological hazards, such as terrain landform, formation lithology, geologic structure pattern, precipitation, earthquake, human activity and so on. finally, as a conclusion., in whole Tibet, the geological hazards are more in southeast than in northwest, more in mountainous area which in the edge of plateau and river valley than in the interior of plateau and lake basin. And most hazards distribute in the regions where human activity is stronger than in other regions, for example towns or strips along the highway.
基金The National Basic Research Program (973 program) (2002CB111506)the R&D Infrastructure and Facility Devel-opment Program (2005DKA32300)
文摘Supported by the spatial analysis feature of geographic information science and assessment model of regional debris flows, hazards degrees of the debris flows in the Upper Yangtze River Watershed （UYRW） are divided into five grades based on grid cell. The area of no danger, light danger, medium danger, severe danger and extreme severe danger regions respectively are 278 000, 288 000, 217 000, 127 000, 15 000 km^2. Furthermore, the counties in the UYRW are classified into four classes based on the hazards degrees in each county. The number of severe danger, medium danger, light danger and no danger counties respectively are 49, 82, 77 and 105. The assessment results will be provided for the hazards forecasting and mitigation in the UYRW and ongoing regionalization of Main Function Regions in China as data and technique framework.
