scholarly journals A scenario analysis under epistemic uncertainty in Natech accidents: imprecise probability reasoning in Bayesian Network

2022 ◽  
Author(s):  
Qiuhan Wang ◽  
Mei Cai ◽  
Wei Guo
Keyword(s):  
Bayesian Network ◽  
Epistemic Uncertainty ◽  
Evidence Theory ◽  
Imprecise Probabilities ◽  
Natural Factor ◽  
Complex Interdependence ◽  
Inference Algorithms ◽  
Probability Table ◽  
Occurrence Mechanism ◽  
The Impact

Abstract The increasing frequency and severity of Natech accidents warn us to investigate the occurrence mechanism of these events. Cascading disasters chain magnifies the impact of natural hazards due to its propagation through critical infrastructures and socio-economic networks. In order to manipulate imprecise probabilities of cascading events in Natech scenarios, this work proposes an improved Bayesian network （BN） combining with evidence theory to better deal with epistemic uncertainty in Natech accidents than traditional BNs. Effective inference algorithms have been developed to propagate system faulty in a socio-economic system. The conditional probability table (CPT) of BN in the traditional probability approach is modified by utilizing an OR/AND gate to obtain the belief mass propagation in the framework of evidence theory. Our improved Bayesian network methodology makes it possible to assess the impact and damage of Natech accidents under the environment of complex interdependence among accidents with insufficient data. Finally, a case study of Guangdong province, an area prone to natural disasters, is given. The modified Bayesian network is carried out to analyze this area’s Natech scenario. After diagnostic analysis and sensitivity analysis of human factors and the natural factor, we are able to locate the key nodes in the cascading disaster chain. Findings can provide useful theoretical support for urban managers of industrial cities to enhance disaster prevention and mitigation ability.

BAYESIAN RETRIEVAL USING A SIMILARITY-BASED LEMMATIZER

2012 ◽  
Vol 21 (05) ◽  
pp. 1250024
Author(s):  
MANOLIS MARAGOUDAKIS ◽  
DIMITRIOS P. LYRAS ◽  
KYRIAKOS SGARBAS
Keyword(s):  
Bayesian Network ◽  
Ad Hoc ◽  
Language Model ◽  
Input Word ◽  
Morphological Variations ◽  
Web Retrieval ◽  
Inference Algorithms ◽  
Probability Table ◽  
Ad Hoc Retrieval ◽  
Boolean Queries

The present paper describes a Bayesian network approach to Information Retrieval (IR) from Web documents. The network structure provides an intuitive representation of uncertainty relationships and the embedded conditional probability table is used by inference algorithms in an attempt to identify documents that are relevant to the user's needs, expressed in the form of Boolean queries. Our research has been directed in constructing a probabilistic IR framework that focus on assisting users to perform Ad-hoc retrieval of documents from the various domains such as economics, news, sports, etc. Furthermore, users can integrate feedback regarding the relevance of the retrieved documents in an attempt to improve performance on upcoming requests. Towards these goals, we have expanded the traditional Bayesian network IR system and tested it on several Greek web corpora on different application domains. We have developed two different approaches with regards to the structure: a simple one, where the structure is manually provided, and an automated one, where data mining is used in order to extract the network's structure. Results have depicted competitive performance against successful IR models of different theoretical backgrounds, such as the vector space utilizing tf-idf and the probabilistic model of BM25 in terms of precision-recall curves. In order to further improve the performance of the IR system, we have implemented a novel similarity-based lemmatization framework, reducing thus the ambiguity posed by the plethora of morphological variations of the languages in question. The employed lemmatization framework comprises of 3 core components (i.e. the word segregation, the data cleansing and the lemmatization modules) and is language-independent (i.e. can be applied to other languages with morphological peculiarities and thus improve Ad-hoc retrieval) since it achieves the mapping of an input word to its normalized form by employing two state-of-the-art language independent distance metric models, meaning the Levenshtein Edit distance and the Dice coefficient similarity measure, combined with a language model describing the most frequent inflectional suffixes of the examined language. Experimental results support our claim on the significance of this incorporation to Greek texts web retrieval as results improve by a factor of 4% to 11%.

scholarly journals Impact Mechanism of the Ecological Vulnerability of Highly Developed Islands Based on the Bayesian Network Model—Applied to the Changshan Islands

2021 ◽  
Vol 18 (8) ◽  
pp. 4150
Author(s):  
Keyu Qin ◽  
Haijun Huang ◽  
Jingya Liu ◽  
Liwen Yan ◽  
Yanxia Liu ◽  
...  
Keyword(s):  
Bayesian Network ◽  
Network Model ◽  
Geographical Information ◽  
Global Changes ◽  
Bayesian Network Model ◽  
Island Ecosystems ◽  
Impact Mechanism ◽  
The North ◽  
Ecological Vulnerability ◽  
The Impact

Islands are one of the most sensitive interfaces between global changes and land and sea dynamic effects, with high sensitivity and low stability. Therefore, under the dynamic coupling effect of human activities and frequent natural disasters, the vulnerability of the ecological environment of islands shows the characteristics of complexity and diversity. For the protection of island ecosystems, a system for the assessment of island ecosystems and studies on the mechanism of island ecological vulnerability are highly crucial. In this study, the North and South Changshan Islands of China were selected as the study area. Considering various impact factors of island ecological vulnerability, the geographical information systems (GIS) spatial analysis, field surveys, data sampling were used to evaluate island ecological vulnerability. The Bayesian network model was used to explore the impact mechanism of ecological vulnerability. The results showed that the ecological vulnerability of the North Changshan Island is higher than that of the South Changshan Island. Among all the indicators, the proportion of net primary productivity (NPP) and the steep slope has the strongest correlation with ecological vulnerability. This study can be used as references in the relevant departments to formulate management policies and promote the sustainable development of islands and their surrounding waters

scholarly journals Understanding epistemic uncertainty in large-scale coastal flood risk assessment for present and future climates

2018 ◽  
Author(s):  
Michalis I. Vousdoukas ◽  
Dimitrios Bouziotas ◽  
Alessio Giardino ◽  
Laurens M. Bouwer ◽  
Evangelos Voukouvalas ◽  
...  
Keyword(s):  
Climate Change ◽  
Risk Assessment ◽  
Flood Risk ◽  
Large Scale ◽  
Epistemic Uncertainty ◽  
Coastal Protection ◽  
Flood Risk Assessment ◽  
Coastal Flood ◽  
Coastal Flood Risk ◽  
The Impact

Abstract. An upscaling of flood risk assessment frameworks beyond regional and national scales has taken place during recent years, with a number of large-scale models emerging as tools for hotspot identification, support for international policy-making and harmonization of climate change adaptation strategies. There is, however, limited insight on the scaling effects and structural limitations of flood risk models and, therefore, the underlying uncertainty. In light of this, we examine key sources of epistemic uncertainty in the Coastal Flood Risk (CFR) modelling chain: (i) the inclusion and interaction of different hydraulic components leading to extreme sea-level (ESL); (ii) inundation modelling; (iii) the underlying uncertainty in the Digital Elevation Model (DEM); (iv) flood defence information; (v) the assumptions behind the use of depth-damage functions that express vulnerability; and (vi) different climate change projections. The impact of these uncertainties to estimated Expected Annual Damage (EAD) for present and future climates is evaluated in a dual case study in Faro, Portugal and in the Iberian Peninsula. The ranking of the uncertainty factors varies among the different case studies, baseline CFR estimates, as well as their absolute/relative changes. We find that uncertainty from ESL contributions, and in particular the way waves are treated, can be higher than the uncertainty of the two greenhouse gas emission projections and six climate models that are used. Of comparable importance is the quality of information on coastal protection levels and DEM information. In the absence of large-extent datasets with sufficient resolution and accuracy the latter two factors are the main bottlenecks in terms of large-scale CFR assessment quality.

scholarly journals Environmental Conditions as a Factor of Influence on the Everyday Life of the Orthodox Population of Ukrainian Lands of the Second Half of the 16th-17th Centuries

2020 ◽  
pp. 9-17
Author(s):  
Inna Goncharenko ◽  
Keyword(s):  
Everyday Life ◽  
Mutual Influence ◽  
Human Life ◽  
Main Task ◽  
Wild Animals ◽  
Natural Conditions ◽  
Natural Factor ◽  
Production Practices ◽  
The Impact ◽  
Factor Of Influence

The purpose of this article is to analyze natural conditions as a significant factor of influence on everyday life, practices and strategies for the survival of the population of Ukrainian lands in the second half of the 16th – 17th centuries. The main task of the study is to reconstruct the environment of the second half of the 16th – 17th centuries and to identify the mutual influence of man and nature. Research methodology: the following methods were used: general scientific – historical and logical, analysis and synthesis, generalization; special – historical-systemic, historical reconstruction, which consists in drawing up a fairly complete picture of everyday life from disparate facts. Scientific novelty: the natural factor in the pre-industrial era is significantly underestimated in the studies of everyday life and is one of the most significant in the impact on human life, but it is ignored in modern historical works. Therefore, the analysis of the natural conditions of everyday life, especially in the early modern era, is relevant today. Conclusions. The analysis of the influence of natural conditions on everyday life of the population shows that a significant part of the population in one way or another was engaged in the transformation of nature in their production practices and was largely dependent on the environment. In the minds of the population, nature was seen as an endless resource for consumption. When assessing the influence of nature on everyday life in the second half of the 16th – 17th centuries, emphasis should be placed on the fact that during this period there was a combination of reproduction and appropriating forms of the economy in everyday production practices. The richness of natural resources, the fertility of the soil helped people to survive, but everyday survival was often due to the merciless exploitation of nature, especially in forests and wild animals. Parallel to this, there are attempts to protect resources from overuse by granting privileges to a limited number of consumers and legislative regulation. In general, the environmental circumstances of everyday life of the specified period cannot be characterized as stable due to the reduction of forest, plowing of virgin lands, excessive extermination of wild animals.

scholarly journals Live wildlife trade in markets - a scoping review to inform risk assessment of emerging infectious diseases

2021 ◽  
Author(s):  
Victoria J Brookes ◽  
Okta Wismandanu ◽  
Etih Sudarnika ◽  
Justin A Roby ◽  
Lynne Hayes ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Infectious Diseases ◽  
Scoping Review ◽  
Epistemic Uncertainty ◽  
Mammalian Species ◽  
Emerging Infectious Diseases ◽  
World Health Organisation ◽  
World Health ◽  
Wildlife Trade ◽  
The Impact

Wet markets are important for food security in many regions worldwide but have come under scrutiny due to their potential role in the emergence of infectious diseases. The sale of live wildlife has been highlighted as a particular risk, and the World Health Organisation has called for the banning of live, wild-caught mammalian species in markets unless risk assessment and effective regulations are in place. Following PRISMA guidelines, we conducted a global scoping review of peer-reviewed information about the sale of live, terrestrial wildlife in markets that are likely to sell fresh food, and collated data about the characteristics of such markets, activities involving live wildlife, the species sold, their purpose, and animal, human, and environmental health risks that were identified. Of the 59 peer-reviewed records within scope, only 25% (n = 14) focussed on disease risks; the rest focused on the impact of wildlife sale on conservation. Although there were some global patterns (for example, the types of markets and purpose of sale of wildlife), there was wide diversity and huge epistemic uncertainty in all aspects associated with live, terrestrial wildlife sale in markets such that the feasibility of accurate assessment of the risk of emerging infectious disease associated with live wildlife trade in markets is limited. Given the value of both wet markets and wildlife trade and the need to support food affordability and accessibility, conservation, public health, and the social and economic aspects of livelihoods of often vulnerable people, there are major information gaps that need to be addressed to develop evidence-based policy in this environment. This review identifies these gaps and provides a foundation from which information for risk assessments can be collected.

Improvement of Acupuncture Therapy on Relapse of P atients with G outy A rthritis: A Pairwise and Bayesian Network Meta analysis

2021 ◽  
Author(s):  
Zhihui Li ◽  
Min Chen ◽  
Chunzhi Tang
Keyword(s):  
Acupuncture Therapy ◽  
Bayesian Network ◽  
Meta Analysis ◽  
Gouty Arthritis ◽  
Serum Urate ◽  
Cochrane Library ◽  
Future Research ◽  
Fire Needle ◽  
The Impact

Objective: The aim of this study is to investigate the impact of acupuncturetherapy on relapse of patients with gouty arthritis (GA). Methods: “gout ORgouty arthritis” AND “a cupuncture therapy OR acupuncture OR moxibustionOR electroacupuncture OR fire needle OR acupotomology OR blood lettingpuncture OR plum blossom needle” were used as search strategies forsearching related studies. Twenty two studies involving 2394 patient s wereenrolled in this research through the analysis of databases of CNKI, Wanfang,VIP, PubMed, Embase and Cochrane Library. Results: The results of pairwise metaanalysis and network meta analysis (NMA) indicated that patients withacupuncture therapy had a significantly lower relapse rate (RR) compared withthose without acupuncture therapy (OR = 0.21, 95% CI: 0.16 0.26, P <0.00001); the follow up time (TFU) and serum urate concentration (SUA)before treatment had no significant effect on the reductio n of RR caused byacupuncture therapy (P > 0.05); and patients treated with acupuncture plusWestern medicine (WM) had the lowest RR (surface under the cumulativeranking [SUCRA] = 85.0%), followed by acupuncture plus traditional Chinesemedicine (TCM, SUC RA = 73.5%), acupuncture only (SUCRA = 72.8%),fourthly acupuncture plus TCM and WM (SUCRA = 33.0%), then TCM(SUCRA = 28.7%), finally WM (SUCRA = 7.0%). Conclusion: Our findingmay facilitate the application of acupuncture therapy in patients with GA. Ourresearch also offered some information for the future research.

Absolute humidity of atmospheric air and COVID-19

2021 ◽  
pp. 8-24
Author(s):  
Vladimir Vasilievich Krivosheev ◽  
Artem Igorevich Stolyarov ◽  
Aleksandr Aleksandrovich Semenov
Keyword(s):  
Relative Humidity ◽  
Absolute Humidity ◽  
Atmospheric Parameter ◽  
Natural Factor ◽  
Incidence And Mortality ◽  
Optimal Value ◽  
Negative Effect ◽  
Northern Territories ◽  
High Degree ◽  
The Impact

Today COVID-19 is number one global point of focus. Therefore, study of the effects of environmental conditions, in which exist pandemic subjects — people and viruses, on pandemic dynamics and results is extremely important. The authors made a correlation analysis of dependence between incidence/mortality of population and absolute and relative humidity in 73 countries and regions on different continents of the Earth. The methodology developed defines how and in what periods of time the environmental factors effect on human incidence and mortality, how strongly particular atmospheric parameter affects the process of infection and disease flow. The undertaken calculations allowed to prove that the absolute humidity is one of the dominant natural factor which influences on pandemic COVID-19 and other infectious diseases dynamics. The growth of absolute air humidity can have both positive and negative effect on incidence and mortality of population while the effect’s character depends on absolute humidity’s own level and other atmospheric parameters. Correlation of absolute and relative humidity with incidence/mortality at the same time can be different in value or sign. Existing regulations at the federal level in Russian Federation are established without taking into account the minimum allowable and physiologically optimal value of absolute humidity, and need corrections. The question of the impact of absolute humidity is of great importance for northern territories, where most of the year the value of absolute humidity is less than the minimum allowed. The achieved results show high degree of the impact of absolute humidity on incidence and mortality of population due to COVID-19 and contribute to better understanding of pandemic peaks cyclicality and conscious forecasting of start of periods of the most dangerous epidemiological reality.

scholarly journals Risk Analysis of Urban Dirty Bomb Attacking Based on Bayesian Network

2019 ◽  
Vol 11 (2) ◽  
pp. 306 ◽  
Author(s):  
Zheng Tang ◽  
Yijia Li ◽  
Xiaofeng Hu ◽  
Huanggang Wu
Keyword(s):  
Bayesian Network ◽  
Emergency Response ◽  
Wind Fields ◽  
Occurrence Time ◽  
Dirty Bomb ◽  
Urban Security ◽  
The Impact ◽  
Special Time ◽  
Attack Location ◽  
Security Check

Urban dirty bomb attacking is a type of unconventional terrorism threatening the urban security all through the world. In this paper, a Bayesian network of urban dirty bomb attacking is established to analyze the risk of urban dirty bomb attacking. The impacts of factors such as occurrence time, location, wind fields, the size of dirty bomb, emergency response and defense approaches on casualty from both direct blast and radiation-caused cancers are examined. Results show that sensitivity of casualty from cancers to wind fields are less significant; the impact of emergency response on the direct casualty from blast is not large; the size of the dirty bomb results in more casualties from cancers than that from bomb explosions; Whether an attack is detected by the police is not that related to normal or special time, but significantly depends on the attack location; Furthermore, casualty from cancers significantly depends on the location, while casualty from blast is not considerably influenced by the attacking location; patrol and surveillance are less important than security check in terms of controlling the risk of urban dirt bomb, and security check is the most effective approach to decreasing the risk of urban dirty bomb.

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