Disaster Control Research Articles

Spatiotemporal variability of drought/flood and its teleconnection with large-scale climate indices based on standard precipitation index: a case study of Taihu Basin, China.

With the intensification of global warming, frequency of floods and droughts has been increasing. Understanding their long-term characteristics and possible relationship with large-scale meteorological factors is essential. In this study, we apply signal denoising, dimensionality reduction technique, and wavelet transform to study the spatiotemporal distribution pattern of drought/flood and its teleconnection with large-scale climate indices. Based on the precipitation data of 63 hydrological stations in the Taihu Lake Basin (TLB) for 54 years from 1965 to 2018, the standard precipitation index (SPI) was used as an indicator. The ensemble empirical mode decomposition (EEMD) and empirical orthogonal function (EOF) methods were used to explore the spatiotemporal evolution characteristics of droughts and floods. In addition, the cross-wavelet transform (XWT) method was used for teleconnection analysis. The results indicated that during 1965-2018, the SPI of the TLB showed quasiperiodic oscillations dominated by interannual oscillations (52.5%). Except for the trend of drought in spring, the basin showed a wetter trend at annual, summer, autumn, and winter scales. There were two main spatial modes (total 78.48% contribution) in the TLB, consistent across the region and reverse distributed from south to north. The dry areas were mainly in southern Zhexi and the northern Huxi sub-regions; the Hangjiahu and Yangchengdianmao sub-regions were prone to flooding. In addition, SPI was correlated with various large-scale meteorological factors, but the strength of the correlation had specific temporal and spatial heterogeneity. The research results can provide TLB reference values for water resource management and flood/drought disaster control.

Web GIS for Sustainable Education: Towards Natural Disaster Education for High School Students

The rapid development of the web geographic information system (Web GIS) has promoted new vitality in high school geography education, relieved the stress of geography teachers caused by software and technical problems, and made it possible for teachers to devote more energy to geography teaching and research activities. Natural disaster education is not only an important part of the geography curriculum, but also an indispensable aspect of education for sustainable development (ESD) for high school students. The application of Web GIS in the dynamic monitoring, forecast, and early warning of natural disasters is becoming more experienced. Therefore, the application of Web GIS in natural disaster education is quite feasible. How to build a bridge between them is the purpose of this paper. Thus, the paper selects ArcGIS Online, which is not limited by time and space, and analyzes several functions that apply it to geography teaching. These include smart mapping, story maps, 3D web maps, and mobile GIS. Meanwhile, it analyzes the knowledge structure of “natural disasters” in Chinese geography textbooks to guide the subsequent case design. Then, the Web GIS inquiry-based teaching case is formed based on “7.20 Zhengzhou Torrential Rain”. It contains knowledge about natural disasters and designs from many aspects, such as the causes, manifestations, and prevention and control of disasters. The discussion identifies a range of specific educational benefits of applying Web GIS to natural disaster education for teachers and schools. Ultimately, it can provide some reference values for geography teachers and other developers to explore curriculum resources and create quality educational models.

Remote Real-Time Monitoring System for Mine Slope Based on Cloud Computing

A remote real-time monitoring system was developed for the remote real-time monitoring of mine slope deformation and internal forces. The system is based on cloud-computing technology and a 5S multimedia streaming monitoring data transmission system. It has now been applied to an open-pit iron mine in Nanfen to monitor the horizontal displacement of potential sliding surfaces. Compared with geometric monitoring methods in traditional geodetic surveying, the results show that this monitoring system has higher accuracy (0.01 mm) and the ability to monitor in real time for 24 h. These features can realize early warnings of mine slopes from multiple dimensions, and provide a guarantee for safe, continuous and the efficient production of mines. In addition, it can provide a certain reference for the prevention and control of mine slope disasters, and is beneficial to the application of information-based early warning technology.

Study on the Failure Mechanism and Permeability Characteristics of Gas Containing Sandstone Intercalated Coal.

The deformation failure mechanism and permeability characteristics of loaded coal sandstone samples under triaxial stress loading were analyzed based on the experimental platform of the coal-rock fluid solid coupling triaxial servo system. The results show that the stress–strain curve of coal intercalated sandstone can be divided into five stages: compaction closure, elastic deformation, stable fracture expansion, unstable fracture expansion, and post-peak strain softening. With the increase of confining pressure, the peak strength and residual strength of the sample increase linearly with the confining pressure. The permeability of the sample decreases slowly with the increase of axial strain, increases rapidly after reaching the stage of unstable fracture propagation, and changes in “V” shape. The relationship between initial permeability and confining pressure can be fitted with exponential function. Based on the fracture volumetric strain model, the progressive failure mechanism of damage expansion of coal mixed sandstone is discussed. The fracture volume strain of each sample under different stress states is given, and the failure mode and crack distribution characteristics of the sample are obtained. The research results can provide reference for reasonable, safe, and efficient coal mining and gas disaster control.

Macro-meso damage and fracture model for determining the creep characteristics of shale under osmotic pressuresure

disturbance of coal mining in water-rich environment can cause damage and rupture of surrounding rocks. In this study, using deep shale as the research object, a rock percolation-disturbance creep test rig has been developed to conduct triaxial compression tests for determining the creep characteristics of the shale under different disturbance parameters. Specifically, the effects of seepage pressure, disturbance amplitude, and disturbance frequency on the creep and meso-mechanical properties of shale are examined by scanning electron microscopy. The results show that with the increase in the disturbance amplitude, disturbance frequency, and seepage pressure, the number of macroscopic cracks on the shale surface increases, and the distribution and propagation mode of cracks become complicated. The sensitivity of the axial strain of shale to the disturbance amplitude, disturbance frequency, and osmotic pressure follows this order: osmotic pressure > disturbance amplitude > disturbance frequency. With the increase in the disturbance amplitude and frequency, many small block structures appear in the shale section, and the surface flatness decreases. However, with the increase in the osmotic pressure, the flatness of the shale section increases, and the section tends to be smooth. As the osmotic pressure increases, the fracture mode of shale is mainly transformed from single brittle fracture to a complex fracture mode of brittle fracture (dominant) and ductile fracture. A fractional nonlinear perturbation creep model of shale under osmotic pressure is established and its reliability and applicability is verified through the experimental results. Overall, the presented results can serve as theoretical reference for the prevention and control of mine water inrush disaster in water-rich areas.

The influence of wind deflectors on the snow distribution in road cuttings during snowdrift

The prevention and control of wind-induced snow disasters in traffic lines are significant for ensuring traffic operation in high-latitude, cold areas. Many unsolved problems still exist due to the complicated mechanism of snowdrift formation. Wind-guiding measures may effectively reduce drifting snow disasters in traffic lines. By using computational fluid dynamics (CFD), the effects of three wind deflectors (vertical, backward, and forward types) on wind-induced snow accumulation in a typical cutting are discussed. We analyze the effect of the wind deflector on reducing snow deposition in terms of the flow field, deposition length, and snow facies concentration. The results show that the inclination angle of the wind deflector is a key parameter that affects snow disaster prevention. It is recommended that a forward-inclined wind deflector should be selected in practice, and the angle between the wind deflector and vertical axis should be controlled at approximately 45°.

Evaluating tropical drought risk by combining open access gridded vulnerability and hazard data products

Droughts are causing severe damages to tropical countries worldwide. Although water abundant, their resilience to water shortages during dry periods is often low. As there is little knowledge about tropical drought characteristics, reliable methodologies to evaluate drought risk in data scarce tropical regions are needed.We combined drought hazard and vulnerability related data to assess drought risk in four rural tropical study regions, the Muriaé basin, Southeast Brazil, the Tempisque-Bebedero basin in Costa Rica, the upper part of the Magdalena basin, Colombia and the Srepok, shared by Cambodia and Vietnam. Drought hazard was analyzed using the variables daily river discharge, precipitation and vegetation condition. Drought vulnerability was assessed based on regionally available socioeconomic data. Besides illustrating the relative severity of each indicator value, we developed drought risk maps combining hazard and vulnerability for each grid-cell.While for the Muriaé, our results identified the downstream area as being exposed to severe drought risk, the Tempisque showed highest risk along the major streams and related irrigation systems. Risk hotspots in the Upper Magdalena were found in the central valley and the dryer Southeast and in the Srepok in the agricultural areas of Vietnam and downstream Cambodia. Local scientists and stakeholders have validated our results and we believe that our drought risk assessment methodology for data scarce and rural tropical regions offers a holistic, science based and innovative framework to generate relevant drought related information.Being applied to other tropical catchments, the approaches described in this article will enable the selection of data sets, indices and their classification - depending on basin size, spatial resolution and seasonality. At its current stage, the outcomes of this study provide relevant information for regional planners and water managers dealing with the control of future drought disasters in tropical regions.

Characteristics of Infrared Radiation in the Failure of Phosphate Rock at Different Loading Rates

Safe and effective mining of phosphate rock plays an important role in the sustainable development of phosphorus resources. The mechanical properties and failure process of phosphate rock under different mining rates remain unclear, further restricting the safe and efficient mining of phosphate rock. In this paper, infrared radiation and uniaxial compression tests of phosphate rock under different loading rates, e.g., 0.0005, 0.001, 0.005, and 0.01 mm/s, were conducted to investigate the failure process of phosphate rock. Energy evolution and infrared radiation characteristics of the phosphate rock damage process were analyzed using nondestructive, real-time, and noncontact infrared thermal imaging technology. The results show that the higher the loading rate of phosphate rock, the more obvious the high-temperature zone and high-temperature point of phosphate rock in the loading process. At failure, the friction and slippage between internal cracks are intense, showing that the infrared radiation temperature difference increases with the increase of loading rate. As loading rate increases, the energy release time of phosphate rock before damage is reduced, resulting in more energy stored in the rock as evinced by its infrared radiation characteristics, finally resulting in greater damage. The increase of loading rate reduces the dissipation energy of phosphate rock before failure so that more energy remains in the rock mass through the weak surface of the grain boundary. The results of this work will be helpful in enhancing theoretical support for prevention and control of dynamic disasters in phosphate mines.

Does the Policy of Ecological Forest Rangers (EFRs) for the Impoverished Populations Reduce Forest Disasters?—Empirical Evidence from China

The effective prevention and control of forest disasters is important for forest resources and the well-being of those living in forested areas. This study evaluates the impact of a policy that employs a rural impoverished population as ecological forest rangers (EFRs) for the incidence of forest disasters. We estimate a generalized difference in differences (DID) model using nationwide provincial-level forest disaster data combined with regional data in all policy pilot areas. There are three primary findings. (1) The implementation of the EFR policy failed to effectively reduce the incidence of forest fires, forest pests, forest diseases, forest rodents and other forest disasters, which shows that the EFR policy has not achieved the goal of “forest protection”. (2) The effect of the EFR policy on forest disaster control is not significantly different among provinces with different forest resource endowments and different levels of social and economic development. This shows that there is no significant difference in the implementation of EFR policies between different forest resource endowments and different socioeconomic development areas. (3) The EFR policy failed to achieve the effective coordination of the dual goals of “poverty reduction” and “ecological protection”; this is the main reason for the failure to reduce the incidence of forest disasters while reducing poverty. The pressure of this policy neglected the “forest management and protection” function of the policy and the corresponding assessment requirements. At the same time, the central government also neglected the assessment of the prevention and control of “forest disasters” by local governments when implementing this policy. Ultimately, the opportunism of local governments and ecological rangers was strengthened. Therefore, the goals of environmental service payment items and the corresponding evaluation index settings need to be matched to truly achieve the established goals.

Pest Identification and Counting of Yellow Plate in Field Based on Improved Mask R‐CNN

Insect identification is the basis of insect research and disaster control and is of great importance for the design of pest control strategies and the protection of beneficial insects. Due to human subjective limitations and the small size and uneven distribution of pests, traditional methods of distinguishing and counting pest types based on experience cannot quickly and accurately detect and identify pests. Therefore, this paper proposes an object detection algorithm based on the improved Mask R‐CNN model, aiming to improve the accuracy and efficiency in pest identification and counting. The algorithm improves the FPN structure in the feature extraction network and increases the weight coefficient when fusing feature layers of different scales. Based on the task of target detection and recognition, weight coefficient is adjusted to a proper parameter so that the semantic information and positioning information can be made full use to achieve more accurate recognition and positioning. The results of the experimental analysis of 1000 sample images show that the improved Mask R‐CNN model has a recognition and detection accuracy of 99.4%, which is 2.7% higher than that of the unimproved Mask R‐CNN model. The main contribution of this method is to improve the detection speed, and at the same time, the recognition accuracy has been significantly improved. This algorithm provides technical support for pest detection in the agricultural field and makes a contribution to the intellectualization of agricultural management.

Summary of Information Monitoring Methods and Principles of Debris Flow Disasters

Debris flow is a sudden geological disaster, once it occurs, it will cause irreparable economic losses and casualties. In recent years, debris flow disaster control methods emerge in endlessly, among which monitoring and early warning method is the most effective and economic method. In this paper, through the analysis of the monitoring content of material source, water source, characteristics of debris flow mass and the comparison of the current monitoring technology and methods, which is conducive to the selection of monitoring methods for the prevention and control of actual geological disasters, which can avoid the waste of resources.

Experience and enlightenment of urban waterlogging disaster prevention in foreign countries

As an important type of disaster, urban waterlogging has become a great challenge for urban governance around the world, threatening people’s lives, health and safety and property safety. The United States, Britain, Japan, Singapore and other countries have accumulated rich experience in the prevention and control of urban waterlogging. Foreign countries have strengthened the prevention and control of urban waterlogging disasters mainly in terms of condensing concepts and awareness, improving laws and regulations, paying attention to planning and construction, using scientific and technological means, strengthening knowledge popularization, strengthening risk assessment and early warning, implementing project-driven and active participation of multiple subjects, and achieved certain results. It is of reference and enlightening significance. In terms of the current and future urban waterlogging prevention and control in China, we should continuously improve the concept and awareness of urban waterlogging prevention and control, scientifically and systematically plan and construct the city; comprehensively use various policies and scientific and technological effective means to improve the effectiveness of urban waterlogging prevention; pay attention to waterlogging Risk assessment and disaster early warning work to realize the advancement of waterlogging disaster governance; strengthen knowledge promotion, popularization and multi-subject participation, create a joint force in urban waterlogging prevention and governance, and promote the modernization of urban waterlogging management systems and capabilities.

Transient analysis of a Markovian N-policy queue with system disaster repair closedown setup times and control of admission

Transient analysis of a Markovian N-policy queue with system disaster repair closedown setup times and control of admission

THE DYNAMIC EFFECTS OF DIFFERENT QUARANTINE MEASURES ON THE SPREAD OF COVID-19

<abstract> COVID-19 is pandemic worldwide, and different countries have adopted different measures to stop the spread of the epidemic. In order to study the impact of quarantining close contacts on the spread of coronavirus disease 2019 (COVID-19), based on data published by Beijing Municipal Health Commission, World Health Organization (WHO) and Korea Central Disaster Control Headquarters (KCDC), SEIR dynamic models of virus transmission in Beijing and South Korea were set up respectively; the Genetic algorithm was used to fit the important parameters such as transmission rate, recovery rate and quarantine rate; calculated the control reproduction number; we discuss the impact of quarantining close contacts on daily new cases in South Korea, the daily new cases decrease after a week, and drop to 16.93 after 30 days. When close contacts were quarantined, the maximum value of daily new cases $ I_{max}=57.4 $ obtained by simulation is only 13% of the actual maximum value actual $ I_{max}=441 $; the influences of different quarantine rates and the number of the susceptible on the number of daily new cases are also discussed, the quarantine of close contacts has significant effect on reducing the number of daily new cases compared with less stringent control measures. Vigorous control measures reduce the number of daily new cases to single digits in just 17 days in Beijing, effectively curbing the transmission of COVID-19. It has vital significance for the prevention and control of the epidemic in other countries and regions. </abstract>

Predicting cyclone landfall using mutual information and dilated recurrent neural network

Abstract Cyclones are a severe storm system with a defined center, occurring in the tropical regions. Upon landfall, it causes massive damage to both lives and the economy. With the increase in frequency and intensity of tropical cyclones occurring over the years and growing coastal settlements, the study of cyclone landfall remains of paramount importance for disaster control and mitigation. Cyclones experience rapid changes, with various environmental factors modulating the trajectory and intensity. Thus predicting cyclone landfall demands a highly precise technique coupled with knowledge of environmental parameters. With the complexity and nonlinearity of the cyclone track data, determining parameters conducive for the landfall prediction of a cyclone remains crucial for precision and knowledge of the storm system. While numerous methods have been employed for detecting causal interactions among weather systems like Granger Causality and Transfer Entropy, each comes with its limitation and computational overhead. In this work, we investigate the where and when of a cyclone landfall by studying the influencing factors regulating the location and time of a cyclone landfall over the North Indian Ocean with mutual information (MI). We utilize dilated recurrent neural network with gated recurrent unit cells coupled with feature selection via MI criterion for predicting the cyclone landfall location and intensity between 12 and 36 training hours. The model efficacy is validated further on the landfall data of a recent devastating storm—Fani.

Floods and their problems: Land uses and soil types perspectives

The phenomenon of flooding that occurs in almost all regions of the earth causes loss of property and damage to public facilities and causes the loss of many human lives. There are many reports related to the causes of flooding with various solutions offered to overcome the flood problem. However, it seems that these efforts have not been able to eliminate the flood problem. Hydrologists have widely reported various factors that are the cause of flooding with an extensive scope. Therefore, this paper is limited to discussing flooding and its problems, specifically the river flood, from the perspective of land use and soil types. Changes in land use in a watershed can cause an increase in the runoff coefficient. Likewise, different types of soil have different abilities in passing water into the ground. Open land (without land cover) tends to be prone to erosion, reducing the soil’s infiltration capacity and increased surface runoff. Increasing the runoff coefficient will increase the peak discharge in a watershed. The decrease in the river capacity due to sediment can cause a river flood. To support this argument, a rainfall-runoff model, particularly the tank model, is also discussed, taking into account the various uses and types of soil in a watershed. Efforts to anticipate the river flood are also considered for formulating flood disaster control policies in a watershed.

Historical Evolution of Sustainable Community Economic Development in Business and Economics

Objective - Sustainable Community Economic Development (SCED) has gradually changed overtime from production philosophy to the welfare ideology of assuring a better future for a resilient community in business and economics. SCED contributesto poverty alleviation, employment generation, sustainable community design, disaster control and resilience, biodiversity protection, and much more.The objective of this study is to conduct a literature review of this concept fromthe global and Bangladeshi perspective. Methodology - Peer reviewed publications in English language were considered indexed on the Scopus and Web of Science database. The study designed 2timelines of SCED concept evolution based on the information derived from the existing peer-reviewed publications. Findings - Both timelines (global and Bangladeshi) were found interrelated on some points, especially the third phase of the global SCED connected with the first phase of Bangladesh's SCED timeline, immediately after the Liberation War. Novelty - The study concludes that SCED is an ever-changing area of research and future research would reveal more sustainable features that would increase the sustainability and resilience of the business community. Type of Paper - Review Keywords: Economic Development; Community Economic Development; Sustainable Community Economic Development (SCED); Bangladesh; NGOs; MFIs. JEL Classification: F63, O1, O50.

Investigation of Changes to Triaxial Shear Strength Parameters and Microstructure of Yili Loess with Drying-Wetting Cycles.

This research examined the drying–wetting cycles induced changes in undrained triaxial shear strength parameters and microstructural changes of Yili loess. The drying–wetting cycles were selected as 0, 1, 3, 5, 10, 20 and 30. Then, we collected Yili loess samples and performed unconsolidated-undrained (U-U) triaxial shearing tests to ascertain the variation in shear strength parameters with drying–wetting cycles. Additionally, we investigated the microstructural changes of Yili loess samples under drying–wetting cycles simultaneously via nuclear magnetic resonance (NMR) and scanning electron electroscopy (SEM). Finally, we established a grey correlation model between shear strength and microstructural parameters. Under U-U conditions, the prime finding was that the loess’s shear strength parameters changed overall after drying–wetting cycles; in particular, the internal friction angle φ dropped significantly while the cohesion c changed only slightly during cycles. For all the cycles, the first cycle gave the highest change. Soil morphology deterioration was evident at the initial stage of cycles. During the entire drying–wetting cyclic process, pore size distribution showed progressive variance from two-peak to a single-peak pattern, while both porosity and the fractal dimension of pores increased gradually towards stability. Soil particle morphology became slowly simple and reached the equilibrium state after 20 drying–wetting cycles. Under cyclic drying–wetting stress, the shear strength parameter changes were significantly correlated to microstructural modifications. This investigation was related to loess in the westerly region. The findings were expected to provide new insight into establishment of the connection between microstructure and macro stress–strain state of loess. To some extent, it provided a theoretical basis for the prevention and control of loess engineering geological disasters in Yili, Xinjiang and other areas with similar climate and soil types.

Assessing Risk of Storm Surge for Coastal Provinces in Viet Nam

Viet Nam is seriously affected by natural disasters including storms and storm surges. Assessing disaster risks, particularly storm surges for coastal provinces, thus, provides not only scientific evidence but also supports policymaking in natural disaster prevention and control. Given this importance, this study assesses the risks of storm surges in Vietnamese coastal provinces. The results show that the coastal areas of Quang Ninh, Thanh Hoa, Nghe An, Ha Tinh, Quang Tri and Hue face the highest risk of storm surges. On the contrary, other provinces including Da Nang, Quang Nam, Binh Dinh, Phu Yen, and Ba Ria- Vung Tau face the lowest risk of storm surges. The results provide useful information for better natural disaster preparedness in Viet Nam, namely planning and zoning of future development as well as supporting early warning efforts.

Experimental research on increasing effect of water injection in coal seam with chelating agent

ABSTRACT Coal seam water injection has a significant effect on the prevention and control of coal mine rock burst, and the pore characteristics of the coal seam is an important factor affecting the effect of coal seam water injection. With the deep mining of coal mine, the physical and mechanical properties of coal body change, the porosity of the coal seam decreases, and the injectability of the coal seam becomes worse. With the passage of time the minerals and CO2 in coal makes it more difficult to inject water. In order to obtain the reason why the water injection in coal seam becomes worse, the water injection additive with excellent performance is found, and a series of experiments on the impact tendency of coal body are carried out. The results show that the mine water used for coal seam water injection was liable to precipitate more ions, which may react with CO2 dissolved in water to form precipitates, plug coal pore and reduce the fluidity of water in the coal seam, resulting in poor water injection effect. Adding chelating agent IDS in aqueous solution can effectively prevent precipitation formed by the combination of easily precipitated ions and carbonate ions in it. At the same time, the chelating agent IDS can decompose precipitated ions from the surface of coal particles, change from insoluble to soluble, promote pore development, increase the effect of water injection and the pore diameter of the coal, and reduce hydrophobic groups on the coal surface. IDS can reduce the impact tendency of coal, and it is an environmental protection additive that can increase permeability. It can provide reference for prevention and control of composite power disasters by coal seam water injection.