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1.
Sci Rep ; 14(1): 11399, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762516

RESUMO

The construction of acoustic emission criterion system is crucial for monitoring and providing early warning of geological hazards. In the current soil acoustic emission monitoring methods, the signal generated by soil deformation and failure is weak and experiences high attenuation, resulting in a low level of the monitored signal. One approach to enhance the quality of monitoring data is by utilizing the active waveguide model. However, the current research on the active waveguide model system is not extensive. To address these issues, a set of active waveguide system was designed to improve the data quality of acoustic emission monitoring and early warning. The deformation and failure process of loess monitored by acoustic emission was divided into stages, and the precursor information of acoustic emission for geological disasters in loess areas was comprehensively deconstructed. The data quality advantage of the active waveguide model was verified through comparative experiments of with the passive waveguide model. This study investigates the AE signal characteristics of the active waveguide model. It explores various aspects such as the AE waveform parameter characteristics, the discrimination method for failure mode based on RA-AF value, the AE r-value characteristics, the AE b-value characteristics, and the frequency-amplitude characteristics. The study reveals the evolution law of AE signals in the active waveguide model, including early warning signs and failure morphological characteristics. Furthermore, it constructs a warning criterion for the active waveguide system. The development of this criterion system is of great importance in guiding the monitoring and early warning of geological disasters in loess areas.

2.
Glob Chang Biol ; 29(11): 2893-2925, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36802124

RESUMO

Although our observing capabilities of solar-induced chlorophyll fluorescence (SIF) have been growing rapidly, the quality and consistency of SIF datasets are still in an active stage of research and development. As a result, there are considerable inconsistencies among diverse SIF datasets at all scales and the widespread applications of them have led to contradictory findings. The present review is the second of the two companion reviews, and data oriented. It aims to (1) synthesize the variety, scale, and uncertainty of existing SIF datasets, (2) synthesize the diverse applications in the sector of ecology, agriculture, hydrology, climate, and socioeconomics, and (3) clarify how such data inconsistency superimposed with the theoretical complexities laid out in (Sun et al., 2023) may impact process interpretation of various applications and contribute to inconsistent findings. We emphasize that accurate interpretation of the functional relationships between SIF and other ecological indicators is contingent upon complete understanding of SIF data quality and uncertainty. Biases and uncertainties in SIF observations can significantly confound interpretation of their relationships and how such relationships respond to environmental variations. Built upon our syntheses, we summarize existing gaps and uncertainties in current SIF observations. Further, we offer our perspectives on innovations needed to help improve informing ecosystem structure, function, and service under climate change, including enhancing in-situ SIF observing capability especially in "data desert" regions, improving cross-instrument data standardization and network coordination, and advancing applications by fully harnessing theory and data.


Assuntos
Ecossistema , Fotossíntese , Clorofila , Fluorescência , Estações do Ano
3.
Data Brief ; 47: 108908, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36761405

RESUMO

Flash droughts are characterized by rapid development and intensification, which makes early warning and monitoring difficult. Flash drought monitor (FDM) is a near-real time monitoring system for Spain (https://flash-drought.csic.es) based on the Standardized Precipitation Evapotranspiration Index (SPEI). Flash drought identification was based on rapid and anomalous declines in SPEI at a short time scale (1-month). Thus, FDM enables operational tracking of flash drought conditions in Spain at high spatial resolution (1.1 × 1.1 km) and high temporal frequency (weekly). Likewise, to put flash drought monitoring into a temporal context, the FDM also provides weekly flash drought conditions recorded in Spain from 1961 to the present. The FDM is a useful tool for preparedness and mitigation of flash droughts in Spain. Furthermore, the data provided by the FDM could be useful to develop future studies in relation to the flash drought in Spain.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36429838

RESUMO

For more than 20 years, disaster dynamic monitoring and early warning have achieved orderly and sustainable development in China, forming a systematic academic research system and top-down policy design, which are inseparable from the research of China's scientific community and the promotion of government departments. In the past, most of the research on dynamic disaster monitoring and early warning focused on specific research in a certain field, scene, and discipline, while a few studies focused on research review or policy analysis, and few studies combined macro and meso research reviews in academia with national policy analysis for comparative analysis. It is necessary and urgent to explore the interaction between scholars' research and policy deployment, which can bring theoretical contributions and policy references to the top-down design, implementation promotion, and academic research of China's dynamic disaster monitoring and early warning. Based on 608 international research articles on dynamic disaster monitoring and early warning published by Chinese scholars from 2000-2021 and 187 national policy documents published during this period, this paper conducts a comparative analysis between the knowledge maps of international research hotspots and the co-occurrence maps of policy keywords on dynamic disaster monitoring and early warning. The research shows that in the stage of initial development (2000-2007), international research articles are few and focused, and research hotspots are somewhat alienated from policy keywords. In the stage of rising development (2008-2015), after the Wenchuan earthquake, research hotspots are closely related to policy keywords, mainly in the fields of geology, engineering disasters, meteorological disasters, natural disasters, etc. Meanwhile, research hotspots also focus on cutting-edge technologies and theories, while national-level policy keywords focus more on overall governance and macro promotion, but the two are gradually closely integrated. In the stage of rapid development (2016-2021), with the continuous attention and policy promotion of the national government, the establishment of the Ministry of Emergency Management, and the gradual establishment and improvement of the disaster early warning and monitoring system, research hotspots and policy keywords are integrated and overlapped with each other, realizing the organic linkage and mutual promotion between academic research and political deployment. The motivation, innovation, integration, and transformation of dynamic disaster monitoring and early warning are promoted by both policy and academic research. The institutions that issue policies at the national level include the State Council and relevant departments, the Ministry of Emergency Management, the Ministry of Water Resources, and other national ministries and commissions. The leading affiliated institutions of scholars' international research include China University of Mining and Technology, Chinese Academy of Sciences, Wuhan University, Shandong University of Science and Technology, and other institutions. The disciplines involved are mainly multidisciplinary geosciences, environmental sciences, electrical and electronic engineering, remote sensing, etc. It is worth noting that in the past two to three years, research and policies focusing on COVID-19, public health, epidemic prevention, environmental governance, and emergency management have gradually increased.


Assuntos
COVID-19 , Desastres , Humanos , Conservação dos Recursos Naturais , Política Ambiental , Desastres/prevenção & controle , China
5.
Front Microbiol ; 12: 686025, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421843

RESUMO

Orthotospoviruses are responsible for serious crop losses worldwide. Orthotospoviral diseases have spread rapidly in China over the past 10 years and are now found in 19 provinces. Currently, 17 Orthotospovirus species have been reported in China, including eight newly identified species from this genus. The number of new highly pathogenic Orthotospovirus strains or species has increased, likely because of the virus species diversity, the wide range of available hosts, adaptation of the viruses to different climates, and multiple transmission routes. This review describes the distribution of Orthotospovirus species, host plants, typical symptoms of infection under natural conditions, the systemic infection of host plants, spatial clustering characteristics of virus particles in host cells, and the orthotospoviral infection cycle in the field. The evolutionary relationships of orthotospoviruses isolated from China and epidemiology are also discussed. In order to effectively manage orthotospoviral disease, future research needs to focus on deciphering the underlying mechanisms of systemic infection, studying complex/mixed infections involving the same or different Orthotospovirus species or other viruses, elucidating orthotospovirus adaptative mechanisms to multiple climate types, breeding virus-resistant plants, identifying new strains and species, developing early monitoring and early warning systems for plant infection, and studying infection transmission routes.

6.
Big Data ; 9(5): 373-389, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34227850

RESUMO

Geological hazards (geohazards) are geological processes or phenomena formed under external-induced factors causing losses to human life and property. Geohazards are sudden, cause great harm, and have broad ranges of influence, which bring considerable challenges to geohazard prevention. Monitoring and early warning are the most common strategies to prevent geohazards. With the development of the internet of things (IoT), IoT-based monitoring devices provide rich and fine data, making geohazard monitoring and early warning more accurate and effective. IoT-based monitoring data can be transmitted to a cloud center for processing to provide credible data references for geohazard early warning. However, the massive numbers of IoT devices occupy most resources of the cloud center, which increases the data processing delay. Moreover, limited bandwidth restricts the transmission of large amounts of geohazard monitoring data. Thus, in some cases, cloud computing is not able to meet the real-time requirements of geohazard early warning. Edge computing technology processes data closer to the data source than to the cloud center, which provides the opportunity for the rapid processing of monitoring data. This article presents the general paradigm of edge-based IoT data mining for geohazard prevention, especially monitoring and early warning. The paradigm mainly includes data acquisition, data mining and analysis, and data interpretation. Moreover, a real case is used to illustrate the details of the presented general paradigm. Finally, this article discusses several key problems for the general paradigm of edge-based IoT data mining for geohazard prevention.


Assuntos
Internet das Coisas , Computação em Nuvem , Mineração de Dados , Humanos
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-778297

RESUMO

Objective To establish a scientific, operational monitoring and early warning index system for schistosomiasis, so as to provide scientific evidence for promoting the scientification and standardization of early warning system in Poyang Lake Eco-economic Region. Methods Two rounds of Delphi experts’ interviews were applied to construct Index system. The weight value of each indicator was determined by the Analytic Hierarchy process and improvable proportionate allocation method. Reliability, validity of index system and the rationality of index weight distribution can be evaluated in site investigation. Results The Index system included 3 first-order indicators, 9 second-order indicators, and 35 third-order indicators. The 3 first-order indicators were endemic status, environmental and social factors, control measures, with the weight value of 0.531 0, 0.101 5 and 0.367 5, respectively. For the 9 second-order indicators, the highest weight value was for Infection status of human and livestock (0.179 5)and the lowest for social factors(0.050 6). During site investigation, the Cronbach’s alpha and spit half reliability of the total index system and three first-order indicators were all over 0.90, the Kendall W coefficient for the data collected in site investigation and Delphi consultation was 0.742 (P=0.018). Conclusions The Monitoring and Early Warning Index System for Schistosomiasis is suitable for the infection status of Poyang Lake Eco-economic region. The reliability and validity of index system are satisfactory, and the indicator weight distribution is rational.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-845618

RESUMO

“Tianjin Port 8·12 Catastrophic Explosion Accident” is making us alert. And how to learn lessons from the accident, how to form effective prevention and control strategies, which make us much ponder over. Based on summarizing the experiences of the previous chemical emergencies, from the aspects of monitoring and early warning, disaster assessment, on-site detection, and remote telemetry, this paper expounds the importance of the related mechanism and the hardware construction. Then the serious “bottleneck” in the construction of Chinese chemical defense was pointed out as well as introducing the new development direction of foreign military monitoring and detecting equipments. Our aim is attracting much attention of peers within the discipline, so as to effectively enhance the abilities of monitoring and early warning and emergency handling for chemical defense in China.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-491927

RESUMO

Tianjin Port 8 · 12 Catastrophic Explosion Accidentis making us alert. And how to learn lessons from the acci?dent,how to form effective prevention and control strategies,which make us much ponder over. Based on summarizing the experiences of the previous chemical emergencies,from the aspects of monitoring and early warning,disaster assessment,on-site detection,and remote telemetry,this paper expounds the importance of the related mechanism and the hardware construction. Then the seriousbot?tleneckin the construction of Chinese chemical defense was pointed out as well as introducing the new development direction of for?eign military monitoring and detecting equipments. Our aim is attracting much attention of peers within the discipline ,so as to effec?tively enhance the abilities of monitoring and early warning and emergency handling for chemical defense in China.

10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-845673

RESUMO

Chemical threat is a serious public safety problem we must be facing. And how to effectively deal with it is a priority. Based on the needs of chemical defence in our country, "hierarchical monitoring" technology platform is proposed. From three aspects of monitoring and early warning, on-site detecting and laboratory confirmation, and the international development needs and trends, the comparation of domestic and foreign equipment construction and development suggestions in our country are discussed and reviewed. Our aim is to establish effective monitoring mechanism for chemical defence, so as to nip the chemical threat in the bud or reduce the chemical hazards to the minimum.

11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-600990

RESUMO

Chemical threat is a serious public safety problem we must be facing. And how to effectively deal with it is a priority. Based on the needs of chemical defence in our country, hierarchical monitoring technology platform is proposed. From three aspects of monitoring and early warning, on-site detecting and laboratory confirmation, and the international development needs and trends, the comparation of domestic and foreign equipment construction and development suggestions in our country are discussed and reviewed. Our aim is to establish effective monitoring mechanism for chemical defence, so as to nip the chemical threat in the bud or reduce the chemical hazards to the minimum.

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