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Applying the natural disasters vulnerability evaluation model to the March 2011 north-east Japan earthquake and tsunami

Ruiz Estrada MA, Yap SF, Park D

Disasters, 2014 Jul;38 Suppl 2:S206-29.
PMID: 24905816 DOI: 10.1111/disa.12069

Natural hazards have a potentially large impact on economic growth, but measuring their economic impact is subject to a great deal of uncertainty. The central objective of this paper is to demonstrate a model--the natural disasters vulnerability evaluation (NDVE) model--that can be used to evaluate the impact of natural hazards on gross national product growth. The model is based on five basic indicators-natural hazards growth rates (αi), the national natural hazards vulnerability rate (ΩT), the natural disaster devastation magnitude rate (Π), the economic desgrowth rate (i.e. shrinkage of the economy) (δ), and the NHV surface. In addition, we apply the NDVE model to the north-east Japan earthquake and tsunami of March 2011 to evaluate its impact on the Japanese economy.

Matched MeSH terms: Earthquakes/economics*
Analyzing seismogram of the earthquake C051099C, PNGon UGM, PMG and CHTO observation stations to understand the S and P wave velocity Structure

Santosa BJ

Sains Malaysiana, 2009;38.

This research, compares the observed seismogram of the PNG earthquake, C051099C with its synthetics in UGM, Wanagama, Indonesia, PMG, Port Moresby, PNG and CHTO, Chiang May, Thailand. The synthetic seismogram is calculated using preliminary earth model, which are the IASPEI91 and the anisotropic version of PREM. The seismogram comparison is conducted after imposing a low pass filter whose corner frequency is fixed at 20 mHz. We have found a real discrepancy on the travel time and waveform of some wave phases, namely P, S and Rayleigh and Love surface waves, by seismogram comparison in time domain. To correct the discrepancies, we need to adjust the earth structures, which include the depth of the Moho reflector, the velocity gradient of bh, and the propagation velocity of the P and S waves. The correction has been conducted in the earth layering system from the upper mantle down to the CMB, so that the excellent seismogram fitting was obtained for nearly all phases of the targeted waves. The used wave length for analysing is about 150 km. It turns out that the waveform of the body and surface waves is sensitive to the change of velocity structure. The analysis of repetitive ScS depth phases at closer distance stations gives better opportunity to investigate the S velocity structure near the CMB, something not used by other seismologists.

Matched MeSH terms: Earthquakes
Fulltext Mechanics Model for Simulating RC Hinges under Reversed Cyclic Loading

Shukri AA, Visintin P, Oehlers DJ, Jumaat MZ

Materials (Basel), 2016 Apr 22;9(4).
PMID: 28773430 DOI: 10.3390/ma9040305

Describing the moment rotation (M/θ) behavior of reinforced concrete (RC) hinges is essential in predicting the behavior of RC structures under severe loadings, such as under cyclic earthquake motions and blast loading. The behavior of RC hinges is defined by localized slip or partial interaction (PI) behaviors in both the tension and compression region. In the tension region, slip between the reinforcement and the concrete defines crack spacing, crack opening and closing, and tension stiffening. While in the compression region, slip along concrete to concrete interfaces defines the formation and failure of concrete softening wedges. Being strain-based, commonly-applied analysis techniques, such as the moment curvature approach, cannot directly simulate these PI behaviors because they are localized and displacement based. Therefore, strain-based approaches must resort to empirical factors to define behaviors, such as tension stiffening and concrete softening hinge lengths. In this paper, a displacement-based segmental moment rotation approach, which directly simulates the partial interaction behaviors in both compression and tension, is developed for predicting the M/θ response of an RC beam hinge under cyclic loading. Significantly, in order to develop the segmental approach, a partial interaction model to predict the tension stiffening load slip relationship between the reinforcement and the concrete is developed.

Matched MeSH terms: Earthquakes
Assessing radioactive contaminants in Kathmandu soils: measurement and risk analysis

Upadhyay DR, Koirala G, Shah BR, Tajudin SM, Khanal R

Environ Monit Assess, 2024 Jan 23;196(2):190.
PMID: 38261087 DOI: 10.1007/s10661-023-12284-5

Soil samples from vegetable farmland in densely populated wards of Nepal were analyzed for natural radionuclide levels, employing a NaI(Tl) 3" [Formula: see text] 3" gamma detector. The study aimed to evaluate the causes of radiation risk, attributing it to soil contamination resulting from the rapid urbanization and concretization that followed the earthquake in 2015. The activity concentration of radium-226, thorium-232, and potassium-40 and the ranges observed are 2.080±0.084-33.675±1.356 Bq kg[Formula: see text], 17.222±0.198-119.949±1.379 Bq kg[Formula: see text], and 11.203 ± 0.325-748.828±21.716 Bq kg[Formula: see text], respectively. The average values obtained for hazard indices are as follows: radium equivalent activity (82.779 Bq kg[Formula: see text]), absorbed dose rate (36.394 nGy h[Formula: see text]), annual effective dose equivalent (0.045 mSv yearr[Formula: see text]), gamma index (0.291), external hazard index (0.224), internal hazard index (0.253), excess lifetime cancer risk (0.159), annual gonadal dose equivalent (243.278 mSv year[Formula: see text]), alpha index (0.054), and activity utilization index (0.716). However, in most places, thorium-232 concentration is greater than those of the world average and recommended values. In specific locations such as Ward 4 in Baluwatar, the soil was found to have concentrations of Ra[Formula: see text] and K[Formula: see text] exceeding recommended limits. Despite this localized concern, the overall analysis of hazard indices across the studied areas revealed that most values were within permissible limits. This suggests that, on a broader scale, radiation exposure may not be a significant concern in the investigated regions. Nonetheless, the study recommends regular monitoring in additional locations to ensure a comprehensive and ongoing assessment of radiation levels.

Matched MeSH terms: Earthquakes*
Fulltext Effect of having a subsequent child on the mental health of women who lost a child in the 2008 Sichuan earthquake: a cross-sectional study

Xu Y, Herrman H, Bentley R, Tsutsumi A, Fisher J

Bull World Health Organ, 2014 May 01;92(5):348-55.
PMID: 24839324 DOI: 10.2471/BLT.13.124677

OBJECTIVE: To assess whether having a subsequent child had an effect on the mental health of Chinese mothers who lost a child during an earthquake.
METHODS: A cross-sectional survey of bereaved mothers was conducted 30 to 34 months after the 2008 Sichuan earthquake using individual structured interviews to assess sociodemographic characteristics, post-disaster experiences and mental health. The interviews incorporated standardized psychometric measures of anxiety, depression, post-traumatic stress disorder (PTSD) and complicated grief (CG). Social support was also assessed. An adjusted model taking potential confounders into account was used to explore any association between psychological symptoms and the birth of a subsequent child.
FINDINGS: The prevalence of psychological symptoms was higher in mothers who did not have a child after losing the first one. In an adjusted model, symptoms of anxiety (odds ratio, OR: 3.37; 95% confidence interval, CI: 1.51-7.50), depression (OR: 9.47; 95% CI: 2.58-34.80), PTSD (OR: 5.11; 95% CI: 2.31-11.34) and CG (OR: 10.73; 95% CI: 1.88-61.39) were significantly higher among the 116 women without a subsequent child than among the 110 mothers who had another child after bereavement. More than two thirds of the mothers with new infants had clinically important psychological symptoms.
CONCLUSION: Women who have lost an only child in a natural disaster are especially vulnerable to long-term psychological problems, especially if they have reached an age when conception is difficult. Research should focus on developing and evaluating interventions designed to provide women with psychosocial support and reproductive services.

Matched MeSH terms: Earthquakes
Real-Time Impact Analysis and Response using a New Disaster Metrics: 2018 Sulawesi (Indonesia) Earthquake and Tsunami

Yew Y, Arcos González P, Castro Delgado R

Prehosp Disaster Med, 2020 Feb;35(1):76-82.
PMID: 31928556 DOI: 10.1017/S1049023X19005247

INTRODUCTION: The Richter Scale measures the magnitude of the seismic activity for an earthquake; however, it does not quantify the humanitarian need at the point of impact. This poses a challenge for humanitarian stakeholders in decision and policy making, especially in risk reduction, response, recovery, and reconstruction. The new disaster metrics tool titled "The YEW Disaster Severity Index" (DSI) was developed and presented at the 2017 World Congress of Disaster and Emergency Medicine, May 2017, Toronto, Canada. It uses a median score of three for vulnerability and exposure indicators, a median score percentage of 100%, and medium YEW DSI scoring of four to five as baseline, indicating the ability to cope within local capacity. Therefore, scoring more than baseline coping capacity indicates that external assistance is needed. This special real-time report was presented at the 2nd National Pre-Hospital Care Conference and Championship, October 2018, Malaysia.
REPORT: The aim of this analysis is to present the real-time humanitarian impact and response to the 2018 earthquake and tsunami at Donggala and Palu, Sulawesi in Indonesia using the new disaster metrics YEW DSI. Based on the earthquake (measuring 7.7 on the Richter Scale) and tsunami at Donggala, the humanitarian impact calculated on September 29, 2018 scored 7.4 High in the YEW DSI with 11 of the total 17 indicators scoring more than the baseline coping capacity. The same YEW DSI score of 7.4 was scored on the earthquake and tsunami at Palu, with 13 of the total 17 indicators scoring more than baseline ability to cope within local capacity. Impact analysis reports were sent to relevant authorities on September 30, 2018.
DISCUSSION & CONCLUSION: A State of Emergency was declared for a national response, which indicated an inability to cope within the local capacity, shown by the YEW DSI. The strong correlation between the earthquake magnitude, intensities, and the humanitarian impact at Donggala and Palu reported could be added into the science of knowledge in prehospital care and disaster medicine research and practice. As a conclusion, the real-time disaster response was found to be almost an exact fit with the YEW DSI indicators, demonstrating the inability to cope within the local capacity.

Matched MeSH terms: Earthquakes*
Fulltext Site specific ground response spectra of Bakun

Zainap Lamat, Yuhani Jamian, Mohd Agus Adib Eskandar

Pertanika Journal of Science & Technology, 2017;25(105):23-28.
MyJurnal

Sarawak has experienced several earthquakes of local origin and was also affected by long-distance earthquake that originated from Southern Philippine and the Straits of Macassar, Sulu Sea and Celebes Sea. The objectives for this study were to conduct site specific ground response analysis and develop design response spectra for Bakun area by using 1-D equivalent linear ground response analysis. The site characterisation was carried out utilising the soil profile and soil property data of the selected site. Local surface fault ruptures were investigated for possible hazards due to intraplate earthquakes. Earthquake ground motion records were selected based on characteristics of the controlling earthquakes for an area and the maximum magnitude faults were considered for risk assessment. The site-specific response spectra represent the predicted surface ground motions that reflect the levels of strong motion amplitude and frequency content at a particular site. The site-specific ground response analysis for Bakun site found that the peak ground acceleration at bedrock was amplified from 0.16 g to 0.33 g at the ground surface.

Matched MeSH terms: Earthquakes
Experimental identification on thresholds for early warning of rainfall-induced failure on fractured slopes after giant earthquake

Zong-ji Yang, Taro Uchimura, Jian-ping Qiao, Jian-ping Qiao

Sains Malaysiana, 2017;46:2029-2034.

Prevention and mitigation of rainfall induced geological hazards after the Ms=8 Wenchuan earthquake on May 12th, 2008 were significant for rebuild of earthquake hit regions. After the Wenchuan earthquake, there were tens of thousands of fractured slopes which were broken and loosened by the ground shaking, they were very susceptible to heavy rainfall and change forms into potential debris flows. In order to carry out this disaster reduction and prediction effectively in Longmenshan region, careful real-time monitoring and pre-warning of mountain hazards in both regional and site-specific scales is reasonable as alternatives in Wenchuan earthquake regions. For pre-warning the failure of fractured slopes induced by rainfall, the threshold value or the critical value of the precipitation of hazards should be proposed. However, the identification of critical criterion and parameters to pre-warning is the most difficult issue in mountainous hazards monitoring and pre-warning system especially in the elusive and massive fractured slopes widespread in Wenchuan earthquake regions. In this study, a natural coseismic fractured landslide in the Taziping village, Hongkou County, Dujianyan City, was selected to conduct the field experimental test, in order to identify the threshold parameters and critical criterion of the fractured slopes of Taziping. After the field experimental test, the correlation of rainfall intensity, rainfall duration and accumulative rainfall was investigated. The field experimental test was capable of identifying the threshold factors for failure of rainfall-induced fractured slopes after the giant earthquake.

Matched MeSH terms: Earthquakes