scholarly journals Flood Risk Assessment of Subway Systems in Metropolitan Areas under Land Subsidence Scenario: A Case Study of Beijing

2021 ◽  
Vol 13 (4) ◽  
pp. 637
Author(s):  
Guangpeng Wang ◽  
Yong Liu ◽  
Ziying Hu ◽  
Guoming Zhang ◽  
Jifu Liu ◽  
...  

Flooding is one of the most destructive natural events that severely damage the ground and inundate underground infrastructure. Subway systems in metropolitan areas are susceptible to flooding, which may be exacerbated when land subsidence occurs. However, previous studies have focused on flood risk evaluation on regional/watershed-scales and land subsidence monitoring in plains, instead of on subway flood risk evaluation and how land subsidence aggravates the flood risk in subway systems. Using the proposed risk indicators and field survey data, we present a method assessing the flood risk of metropolitan subway systems under a subsidence condition based on the fuzzy analytic hierarchy process (FAHP) combined with a geographic information system (GIS). We use the regional risk level within the 500 m buffer zone of the subway line to depict the flood risk of the subway system. The proposed method was used to evaluate the flood risk of the Beijing subway system. The results show that the flood risks of the Beijing subway show a ring-like distribution pattern—risk levels decreasing from the central urban area to the suburbs. Very high and high risks are mainly located within third and fourth ring roads, accounting for 63.58% (29.40 km2) and 63.83% (81.19 km2) of the total area. Land subsidence exacerbated the Beijing subway system’s flood risk level—the moderate to very high risk increased by 46.88 km2 (16.33%), indicating that land subsidence is an essential factor affecting the flood risk level of subway systems. In addition to enhancing flood warnings, future subway flooding could be reduced by elevating the height of the stations’ exit (entrance) and installing water stop plates and watertight doors. This study is of great significance for flood warning and prevention in the Beijing subway system; it provides a theoretical basis for flood risk evaluation in other metropolitan areas.

2017 ◽  
pp. 21-41
Author(s):  
Marta Borowska-Stefańska

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.


2021 ◽  
Vol 13 (24) ◽  
pp. 5154
Author(s):  
Guangpeng Wang ◽  
Lianyou Liu ◽  
Peijun Shi ◽  
Guoming Zhang ◽  
Jifu Liu

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.


Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Olanrewaju Samson Olaitan ◽  
Olowoporoku Oluwaseun

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.


2011 ◽  
Vol 26 (S1) ◽  
pp. s149-s149
Author(s):  
W. Du ◽  
G. Fitzgerald

IntroductionMass gatherings pose a significant risk on health and safety. The mass gathering in the subway systems in Beijing represents a daily risk. An average of 4.52 million passengers rode the subway each day between 15 November and 30 November 2010, with the highest daily passenger number totaling 5.14 million. The purpose of this study is to identify the health and safety aspects of mass gatherings in Beijing subways, and proposes strategies that may mitigate these risks.MethodsThe methods included a literature review, field visitation of the subway systems, and interviews of 20 passengers and 10 management personnel from the subway system.ResultsMany safety and health measures has been taken by the Beijing Subway System, including emergency exit signs and other safety signs, prohibition of smoking, firefighting equipment and explosion-proof tanks, safety inspection of bags, and safety education in the subways. However, additional key health and safety aspects were indentified, including: (1) lack of strict flow control of passengers in interchange subway stations; (2) lack of platform safety gates in Line 1, Line 2, Line 13; (3) lack of passenger control during peak hours; (4) lack of biomedical monitoring systems in the subways; and (5) lack of health facilities and rescue equipments in the subways.ConclusionsMass gatherings pose great risks on subway passengers in Beijing, including psychosocial risks, biomedical risks, and environmental risks. Additional safety measures need to be taken to ensure the safety and health of passengers in subways in Beijing.


Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 758 ◽  
Author(s):  
Romulus Costache ◽  
Alina Barbulescu ◽  
Quoc Bao Pham

In the present study, the susceptibility to flash-floods and flooding was studied across the Izvorul Dorului River basin in Romania. In the first phase, three ensemble models were used to determine the susceptibility to flash-floods. These models were generated by a combination of three statistical bivariate methods, namely frequency ratio (FR), weights of evidence (WOE), and statistical index (SI), with fuzzy analytical hierarchy process (FAHP). The result obtained from the application of the FAHP-WOE model had the best performance highlighted by an Area Under Curve—Receiver Operating Characteristics Curve (AUC-ROC) value of 0.837 for the training sample and another of 0.79 for the validation sample. Furthermore, the results offered by FAHP-WOE were weighted on the river network level using the flow accumulation method, through which the valleys with a medium, high, and very high torrential susceptibility were identified. Based on these valleys’ locations, the susceptibility to floods was estimated. Thus, in the first stage, a buffer zone of 200 m was delimited around the identified valleys along which the floods could occur. Once the buffer zone was established, ten flood conditioning factors were used to determine the flood susceptibility through the analytical hierarchy process model. Approximately 25% of the total delimited area had a high and very high flood susceptibility.


Author(s):  
Titin Isna Oesman ◽  
Era Irawan ◽  
Petrus Wisnubroto

Leather handycraft industry produces handicrafts such as bags, shoes, wallets, belts.  On production process atcutting division, work posture condition is too bent. A preliminary study on 20 workers found musculoskeletal complaints was greater than 50% at 16 items, mostly in upper limbs. Based on these complaints, research was on work posture using RULA and Sympton Questionnaire.  Research purposes was to determine the risk level and relationship with UEWMSDs on the worker. The result of RULA found that work posture with RULA score was 7 (seven) that means 3 (three) risk level that very high category, and needs to be repaired as soon as possible. Symptom Questionnaire answer related to worker's complaint, which are complaints of shoulder and arm pain was 50%, pain after work 1-4 years was 85%, duration of illness <1 hour was 85%, move to another part due to illness was 55%, pain increase when the activity was 100%, and pain reduce at rest was 90%. Base on the condition, it was needed to redesigned cutting table evaluated by RULA category 3 (three) based on anthropometry of workers


2021 ◽  
Vol 6 (2) ◽  
pp. 59-69
Author(s):  
Husna Fauzia ◽  
◽  
Eka Cahyaningsih ◽  
Hery Hariyanto ◽  
Satya Nugraha ◽  
...  

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.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Roberto Barbosa dos Santos ◽  
Antônio Edésio Jungles

Construction projects are risky in both physical implementation and management. The characteristics of the risk reinforce the necessity of efficient management to increase the chances of success without commitment to its goals. This study explores the correlation of delay and the schedule performance index (SPI) to evaluate the risk of a construction project completed with time overruns. The hypothesis that the SPI of projects with a delay is distinct from those projects without a delay is assumed. A database with 19 elements was used to test this hypothesis and to calculate limit values to the SPI. Therefore, the risk of delay will be small when the observed SPI is greater than the superior limit and large when the SPI is below the inferior limit. The simplicity involved in the calculation of these values showed an advantage in comparison with other methods of risk evaluation. Another strong point observed is that any company can determine the value of risk by considering its own history and support decisions like doing corrective actions.


2020 ◽  
Vol 202 ◽  
pp. 06028
Author(s):  
Ratna Mustika Anindita ◽  
Indah Susilowati ◽  
Fuad Muhammad

The North coast of Java is increasingly exposed to flood risks due to land subsidence and climate change, resulting in sea-level rise. This paper developed a flood risk spatial index model in the coastal Pekalongan. The model was systematically arranged from various flood risk indicators related to the social, economic, and environment of coastal Pekalongan based on surveys and interviews with the communities and regional governments. These indicators are then integrated into hazard and vulnerability as components of risk. Using the index system method and ArcGIS, the risk index is classified into five levels (very high, high, medium, low, very low) and generated into a flood risk spatial distribution map. We found that the risk in the study area varies between a medium to a very high level of risk. The very high level of risk was located in Tratebang, Pecakaran, and Tegaldowo Village. A risk spatial distribution map can be used to evaluate potential risks and flood mitigation.


2013 ◽  
Vol 11 (2) ◽  
pp. 205-232 ◽  
Author(s):  
Jacob S. Rugh ◽  
Douglas S. Massey

AbstractIn this paper we adjudicate between competing claims of persisting segregation and rapid integration by analyzing trends in residential dissimilarity and spatial isolation for African Americans, Hispanics, and Asians living in 287 consistently defined metropolitan areas from 1970 to 2010. On average, Black segregation and isolation have fallen steadily but still remain very high in many areas, particularly those areas historically characterized by hypersegregation. In contrast, Hispanic segregation has increased slightly but Hispanic isolation has risen substantially owing to rapid population growth. Asian segregation has changed little and remains moderate, and although Asian isolation has increased it remains at low levels compared with other groups. Whites remain quite isolated from all three minority groups in metropolitan America, despite rising diversity and some shifts toward integration from the minority viewpoint.Multivariate analyses reveal that minority segregation and spatial isolation are actively produced in some areas by restrictive density zoning regimes, large and/or rising minority percentages, lagging minority socioeconomic status, and active expressions of anti-Black and anti-Latino sentiment, especially in large metropolitan areas. Areas displaying these characteristics are either integrating very slowly (in the case of Blacks) or becoming more segregated (in the case of Hispanics), whereas those lacking these attributes are clearly moving toward integration, often quite rapidly.


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