Flood Risk Assessment of Metro System Using Improved Trapezoidal Fuzzy AHP: A Case Study of Guangzhou

Metro systems have become high-risk entities due to the increased frequency and severity of urban flooding. Therefore, understanding the flood risk of metro systems is a prerequisite for mega-cities’ flood protection and risk management. This study proposes a method for accurately assessing the flood risk of metro systems based on an improved trapezoidal fuzzy analytic hierarchy process (AHP). We applied this method to assess the flood risk of 14 lines and 268 stations of the Guangzhou Metro. The risk results validation showed that the accuracy of the improved trapezoidal fuzzy AHP (90% match) outperformed the traditional trapezoidal AHP (70% match). The distribution of different flood risk levels in Guangzhou metro lines exhibited a polarization signature. About 69% (155 km2) of very high and high risk zones were concentrated in central urban areas (Yuexiu, Liwan, Tianhe, and Haizhu); the three metro lines with the highest overall risk level were lines 3, 6, and 5; and the metro stations at very high risk were mainly located on metro lines 6, 3, 5, 1, and 2. Based on fieldwork, we suggest raising exits, installing watertight doors, and using early warning strategies to resist metro floods. This study can provide scientific data for decision-makers to reasonably allocate flood prevention resources, which is significant in reducing flood losses and promoting Guangzhou’s sustainable development.

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Flood risk assessment in selected communes of the Łódź region

Space - Society - Economy ◽

10.18778/1733-3180.19.02 ◽

2017 ◽

pp. 21-41

Author(s):

Marta Borowska-Stefańska

Keyword(s):

Flood Risk ◽

Land Development ◽

Risk Level ◽

Individual Risk ◽

Negative Consequences ◽

Risk Levels ◽

Risk Areas ◽

High Flood ◽

Very High ◽

Risk Categories

The aim of the article is to assess the present level of land development of flood risk areas in selected communes of the Łódź province in the context of potential negative consequences for people, the natural environment, cultural heritage and economic operations. The research includes urban as well as urban and rural communes (9 communes in total) of the Łódź province which display high and very high flood risk levels according to the methodology used in Flood protection operating plan for the Łódź province from 2013 ( Plan operacyjny… 2013). Uniejów and Warta have the highest synthetic flood risk levels due to the surface occupied by buildings and areas assigned to individual risk categories. In turn, Łowicz and Tomaszów Mazowiecki (town) display the highest general flood risk level due to diversification of buildings and areas of individual risk categories.

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Flood Risk Assessment in an Underground Railway System under the Impact of Climate Change—A Case Study of the Barcelona Metro

Sustainability ◽

10.3390/su12135291 ◽

2020 ◽

Vol 12 (13) ◽

pp. 5291 ◽

Cited By ~ 2

Author(s):

Edwar Forero-Ortiz ◽

Eduardo Martínez-Gomariz ◽

Manuel Cañas Porcuna ◽

Luca Locatelli ◽

Beniamino Russo

Keyword(s):

Climate Change ◽

High Risk ◽

Flood Risk ◽

Urban Areas ◽

Transport Systems ◽

Maximum Rainfall ◽

Increased Risk ◽

Metro Systems ◽

Flooding Events ◽

The Impact

Flooding events can produce significant disturbances in underground transport systems within urban areas and lead to economic and technical consequences, which can be worsened by variations in the occurrence of climate extremes. Within the framework of the European project RESCCUE (RESilience to cope with Climate Change in Urban arEas—a multi-sectorial approach focusing on water), climate projections for the city of Barcelona manifest meaningful increases in maximum rainfall intensities for the 2100 horizon. A better comprehension of these impacts and their conditions is consequently needed. A hydrodynamic modelling process was carried out on Barcelona Metro Line 3, as it was identified as vulnerable to pluvial flooding events. The Metro line and all its components are simulated in the urban drainage models as a system of computational link and nodes reproducing the main physical characteristics like slopes and cross-sections when embedded in the current 1D/2D hydrodynamic model of Barcelona used in the project RESCCUE. This study presents a risk analysis focused on ensuring transport service continuity in flood events. The results reveal that two of the 26 stations on Metro Line 3 are exposed to a high risk of flooding in current rainfall conditions, and 11 of the 26 stations on Metro Line 3 are exposed to a high risk of flooding in future rainfall conditions for a 20-year return period event, which affects Metro service in terms of increased risk. This research gives insights for stakeholders and policymakers to enhance urban flood risk management, as a reasonable approach to tackle this issue for Metro systems worldwide. This study provides a baseline for assessing potential flood outcomes in Metro systems and can be used to evaluate adaptation measures’ effectiveness.

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Evaluation of Dietary Patterns and Health Status of Young Adults from Turkey: University Students from Urban and Rural Provinces

Advances in Nutrition & Food Science ◽

10.33140/anfs/02/01/00008 ◽

2017 ◽

Vol 2 (1) ◽

Keyword(s):

High Risk ◽

University Students ◽

Fast Food ◽

Consumption Rate ◽

Dietary Habits ◽

Eating Habits ◽

Risk Level ◽

Risk Levels ◽

Main Meal ◽

Very High

Young people’s taking nutrition in a healthy way and their getting proper eating habits are of great importance in terms of both individuals and society as a whole. However, the studies that have been conducted in our country show that the young skip meals, their consumption rate of fruits and vegetables is low and fast-food is their eating habit. This study was conducted with the participation of 617 students selected by random sampling method on a voluntary basis (313 female and 304 male) from the age range of 17-30 who are continuing their education at Ankara University (Faculty of Language, History and Geography) and Cumhuriyet University. In this study where the aim was to determine the basic eating habits, risk levels of eating habits and the frequency of food consumption of university students, students were given a questionnaire and by taking their anthropometric height and weight measures Body Mass Index was evaluated. 5.3% of the students was found to be underweight (<18.5 kg/m2 ), 63.4% was normal (19-24.99 kg/m2 ), 23.2% was overweight (≥25 kg/m2 ) and 8.1% was obese (≥30 kg/m2 ). Whereas the rate of skipping main meal was 33.5%, it was determined that the most skipped meal was lunch. In the evaluation of risk levels of dietary habits, 37.8% of male students are at the high risk level and 2.6% of them are at the very high risk level. Similarly, 39.3% of females are at the high risk level and 1.9% percent of them are at the very high risk level. It was also found that the consumption rate of fruits, vegetables, milk and milk products of students was low. Therefore, it should be provided that young people will stay away unhealthy habits and they will take healthy nutrition.

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Adapting Gravity Model for Predicting the Risk of COVID -19 in Nigeria

Coronaviruses ◽

10.2174/2666796701999200915150039 ◽

2020 ◽

Vol 01 ◽

Author(s):

Olanrewaju Samson Olaitan ◽

Olowoporoku Oluwaseun

Keyword(s):

High Risk ◽

Gross Domestic Product ◽

Gravity Model ◽

Infection Risk ◽

Risk Level ◽

Ogun State ◽

Factors Influencing ◽

Government Data ◽

Housing Standards ◽

Very High

Background: It is against the background of the emerging incidence of coronavirus pandemic in Nigeria, and the need for its management that this study adapts gravity model for predicting the risk of the disease across states of the country. Methods: The paper relied on published government data on population, and gross domestic product, while the distance of town to the nearest international airport was also obtained. These data were log transformed and further used in the calculation of gravity scores for each state of the federation. Results: The study discovered that with the gravity score ranging from 2.942 to 4.437, all the states of the federation have the risk of being infected with the pandemic. Meanwhile Ogun State (4.837) has a very high risk of being infected with the disease. Other states with high risks are Oyo (4.312), Jigawa (4.235), Niger (4.148) and Katsina (4.083). However, Taraba State has the least infection risk of the pandemic in Nigeria. Factors influencing the risk level of the pandemic are proximity, porous boundary between states, and elitism. Conclusion: The paper advocates border settlement planning, review of housing standards, and advocacy for sanitation in different states. It therefore concludes that adequate urban planning in unison with economic and epidemiology techniques will provide a strong strategy for the management of the disease.

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Comparison of the ColiPlate™ Kit with Two Common E. coli Enumeration Methods for Water

Water ◽

10.3390/w13131804 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1804

Author(s):

Cassi J. Gibson ◽

Abraham K. Maritim ◽

Jason W. Marion

Keyword(s):

High Risk ◽

Natural Water ◽

Membrane Filtration ◽

Fecal Contamination ◽

Reference Method ◽

World Health ◽

Risk Levels ◽

E Coli ◽

Field Samples ◽

Very High

Quantitatively assessing fecal indicator bacteria in drinking water from limited resource settings (e.g., disasters, remote areas) can inform public health strategies for reducing waterborne illnesses. This study aimed to compare two common approaches for quantifying Escherichia coli (E. coli) density in natural water versus the ColiPlate™ kit approach. For comparing methods, 41 field samples from natural water sources in Kentucky (USA) were collected. E. coli densities were then determined by (1) membrane filtration in conjunction with modified membrane-thermotolerant E. coli (mTEC) agar, (2) Idexx Quanti-Tray® 2000 with the Colilert® substrate, and (3) the Bluewater Biosciences ColiPlate kit. Significant correlations were observed between E. coli density data for all three methods (p < 0.001). Paired t-test results showed no difference in E. coli densities determined by all the methods (p > 0.05). Upon assigning modified mTEC as the reference method for determining the World Health Organization-assigned “very high-risk” levels of fecal contamination (> 100 E. coli CFU/100 mL), both ColiPlate and Colilert exhibited excellent discrimination for screening very high-risk levels according to the area under the receiver operating characteristic curve (~89%). These data suggest ColiPlate continues to be an effective monitoring tool for quantifying E. coli density and characterizing fecal contamination risks from water.

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Distribution of Flood Risk Area in Bodri Watershed of Kendal Regency

Sriwijaya Journal of Environment ◽

10.22135/sje.2021.6.2.59-69 ◽

2021 ◽

Vol 6 (2) ◽

pp. 59-69

Author(s):

Husna Fauzia ◽

◽

Eka Cahyaningsih ◽

Hery Hariyanto ◽

Satya Nugraha ◽

...

Keyword(s):

Land Use ◽

Spatial Modeling ◽

Flood Risk ◽

Flood Hazard ◽

Risk Level ◽

Flood Hazards ◽

Risk Area ◽

Flood Peak ◽

Risk Levels ◽

Central Java

Flooding is a catastrophic phenomenon that can occur due to various factors, such as uncontrolled landuse changes, climate change, and weather anomalies, and drainage infrastructure damage. The Bodri watershed in Kendal Regency is one of the watersheds in Central Java, which is categorized as critical based on Decree No.328/Menhut-II/2009. Some of the problems in the Bodri watershed include land use that is not suitable for its designation, flooding, erosion, and landslides. This study aims to conduct spatial modeling to create flood hazard maps and flood risk level maps in the Bodri watershed. The method used is hydrograph analysis, flood modeling, potential flood hazards, and flood risk levels. Analysis of the potential for flood hazards from the spatial modeling inundation map with the input of the flood peak return period of 2 years (Q2), 5 years (Q5), and 50 years (Q50). Vulnerability analysis based on land use maps of flood hazard areas. The distribution of flood-prone areas in the Bodri watershed is in Pidodo Kulon Village, Pidodo Wetan Village, and Bangunsari Village.

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Assessing the susceptibility of schools to flood events in Iran

Scientific Reports ◽

10.1038/s41598-020-75291-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Saleh Yousefi ◽

Hamid Reza Pourghasemi ◽

Sayed Naeim Emami ◽

Omid Rahmati ◽

Shahla Tavangar ◽

...

Keyword(s):

Flood Risk ◽

Flood Hazard ◽

Rural Students ◽

Flood Hazards ◽

Analytic Hierarchy ◽

Flood Susceptibility ◽

Susceptibility Maps ◽

High Flood ◽

Analytic Hierarchy Process Method ◽

Very High

Abstract Catastrophic floods cause deaths, injuries, and property damages in communities around the world. The losses can be worse among those who are more vulnerable to exposure and this can be enhanced by communities’ vulnerabilities. People in undeveloped and developing countries, like Iran, are more vulnerable and may be more exposed to flood hazards. In this study we investigate the vulnerabilities of 1622 schools to flood hazard in Chaharmahal and Bakhtiari Province, Iran. We used four machine learning models to produce flood susceptibility maps. The analytic hierarchy process method was enhanced with distance from schools to create a school-focused flood-risk map. The results indicate that 492 rural schools and 147 urban schools are in very high-risk locations. Furthermore, 54% of rural students and 8% of urban students study schools in locations of very high flood risk. The situation should be examined very closely and mitigating actions are urgently needed.

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Flood-Prone Area Assessment Using GIS-Based Multi-Criteria Analysis: A Case Study in Davao Oriental, Philippines

Water ◽

10.3390/w11112203 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2203 ◽

Cited By ~ 7

Author(s):

Cabrera ◽

Lee

Keyword(s):

Flood Risk ◽

Flood Hazard ◽

Drainage Density ◽

Mitigation Strategies ◽

Risk Area ◽

Analytic Hierarchy ◽

Comparison Results ◽

Prone Area ◽

Ground Truthing ◽

Very High

Flooding is one of the major destructive natural disasters in Davao Oriental, Philippines, and results primarily from a high incidence of typhoons and heavy rainfalls. The main objective of this study was to identify flood-prone risk areas by mapping them based on the integration of multiple indicators, including rainfall, slope, elevation, drainage density, soil type, distance to the main channel and population density. For this purpose, a GIS-based flood risk spatial assessment was conducted by using analytic hierarchy process (AHP), weights by rank (WR) and ratio weighting (RW) frameworks to determine the relative importance of each indicator against another in the province of Davao Oriental. The resulting flood-prone areas by the three methods are validated by comparing with the estimated flood map based on ground truthing points from a field survey. The comparison results show that AHP is the most appropriate method among them to assess flood hazard. The result of the AHP flood risk map shows that 95.99% (5451.27 km2) of Davao Oriental is under low and moderate flood risk. The high and very high flood risk area covers approximately 3.39% (192.52 km2) of the province, primarily in the coastal areas. Thirty-one out of the one hundred eighty-three (31/183) barangays (towns) are at a high to very high risk of flooding at current climate, calling for the immediate attention of decision-makers to develop mitigation strategies for the future occurrence of flooding in Davao Oriental.

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Prioritizing Risk-level Factors in Comprehensive Automobile Insurance Management: A Hybrid Multi-criteria Decision-making Model

Global Business Review ◽

10.1177/0972150920932287 ◽

2020 ◽

pp. 097215092093228

Author(s):

Zahra Shams Esfandabadi ◽

Meisam Ranjbari ◽

Simone Domenico Scagnelli

Keyword(s):

Insurance Market ◽

Insurance Companies ◽

Risk Level ◽

Automobile Insurance ◽

Two Phase ◽

Analytic Hierarchy ◽

Factors Affecting ◽

Risk Levels ◽

Fuzzy Delphi ◽

The Individual

An efficient risk-level prediction for newly proposed insurance policies plays a significant role in the survival of companies in the highly competitive insurance market. In Iran, risk assessment in comprehensive automobile insurance, which is a part of motor insurance, is only based on the vehicle attributes without proper consideration of personal and behavioural characteristics of driver(s). As a result, pricing is unfair in most of the cases and this can put insurance companies in an unfavourable financial position due to attracting high-risk drivers instead of low-risk ones. In this scenario, to identify and prioritize important factors affecting risk levels and to move towards a fair ratemaking, a two-phase process based on fuzzy Delphi method (FDM) and fuzzy analytic hierarchy process (FAHP) is proposed in this research. Additionally, similarity aggregation method (SAM) is applied to combine the individual fuzzy opinions of the surveyed experts into a group fuzzy consensus opinion. The results of this empirical study contribute to the insurance market of Iran by proposing appropriate weighting of the relevant risk factors to support stakeholders and policymakers for assessing risks more accurately, as well as designing more effective databases and insurance proposal forms.

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Survival Disparities in Patients with Lymphoma According to Place of Residence and Treatment Provider: A Population-Based Study

Blood ◽

10.1182/blood.v112.11.874.874 ◽

2008 ◽

Vol 112 (11) ◽

pp. 874-874

Author(s):

Fausto R Loberiza ◽

Anthony J Cannon ◽

Dennis D Weisenburger ◽

Julie M. Vose ◽

Matt J. Moehr ◽

...

Keyword(s):

Overall Survival ◽

High Risk ◽

Rural Areas ◽

Urban Areas ◽

Population Based ◽

Place Of Residence ◽

Community Based ◽

Risk Levels ◽

Risk Of Death ◽

Risk Patients

Abstract Objectives: We evaluated the association of the primary area of residence (urban vs. rural) and treatment (trt) provider (university-based vs. community-based) with overall survival in patients with lymphoma, and determined if there are patient subgroups that could benefit from better coordination of care. Methods: We performed a population-based study in 2,330 patients with centrally confirmed lymphoma from Nebraska and surrounding states reported to the Nebraska Lymphoma Study Group between 1982 and 2006. Patient residential ZIP codes at the time to trt were used to determine rural/urban designation, household income and distance to trt center; while trt providers were categorized into university-based or community based. Multivariate analyses were used to group patients into risk levels based on 8 factors found to be associated with survival at the time of trt (age, performance score, Ann Arbor stage, presence of B symptoms, LDH levels, tumor bulk, nodal and extranodal involvement). The following categories were identified: low-risk (1–3 factors), intermediate risk (4–5 factors), and high-risk (≥6 factors). Cox proportional regression analyses, stratified by type of lymphoma (low-grade NHL, high-grade NHL and Hodgkin) were used to evaluate the association between place of residence and trt provider with overall survival. Results: Among urban residents, 321 (14%) were treated by university-based providers (UUB) and 816 (35%) were treated by community-based providers (UCB). Among rural residents, 332 (14%) were treated by university-based providers (RUB) and 861 (37%) were treated by community-based providers (RCB). Patients from rural areas were more likely to be older and Caucasian, with a lower median household income, greater travel distance to seek trt, and more likely to have high-risk disease when compared to patients from urban areas. In multivariate analysis, using all patients regardless of risk level, the relative risk of death (RR) among UUB, UCB and RUB was not statistically different. However, RCB had a higher risk of death RR 1.37, 95% CI 1.14–1.65, p=0.01; RR 1.18, 95% CI 1.04–1.33, p<0.01; and RR 1.26, 95% CI 1.06–1.49, p=0.01 when compared with UUB, UCB and RUB, respectively. This association remained true in both low- and intermediate-risk patients. Among high-risk patients, both RUB and RCB were at higher risk of death when compared with UUB or UCB, while UCB were not different from UUB. We found no differences in progression-free survival according to place of residence and trt provider. The use of stem cell transplantation was significantly higher in patients coming from urban and rural areas treated by university-based providers (UUB 19%, RUB 16%) compared to urban and rural patients treated by community-based providers (UCB 11%, RCB 10%, p < 0.01). Patients from rural areas (RUB and RCB) were slightly less likely to die from lymphoma-related causes than patients from urban areas (75% versus 80%, p=0.04). Conclusion: Overall survival in patients with lymphoma is inferior in patients coming from rural areas. This relationship varies according to treatment provider and pretreatment risk levels. Further studies in patients from rural areas are needed to understand how coordination of care is carried to design appropriate interventions that may improve the disparity noted.

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