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This paper proposes the ductility demands control of reinforced concrete frames under criticalsuccessive earthquakes using evaluation of behavior factors (R factors). The influence of RC frameperiods, PGA and magnitude of mainshocks and aftershocks is also taken into account by 10 training ideal artificial neural network (ANN) and proposing the empirical equations. Firstly, 2D RC frames are implemented in Opensees and then evaluated under as-recorded critical single and successive scenario. R factors are calculated and compared for single and successive cases. It is found that the sequences of critical records decrease R factors and capacity of RC frames about 18% and 30%, respectively. Despite what is necessitated in the seismic design codes, proposing a constant value as R factor for whole RC structure especially under single scenarios cannot lead to proper design of structures. Hence, the idealized multilayer ANNs employed to generate the empirical charts for evaluation of R factors. [ABSTRACT FROM AUTHOR]

The concept of Disaster Risk Management (DRM) has changed throughout history. Identifying changes and related factors can be effective in adopting logical, scientific and evidence-based approaches in the future. Therefore, this study was conducted with the aim of depicting the process of changes in the concept of DRM and creating an original perspective. In this narrative literature review study, we used historical approach. Literature, regardless of the time of publication, was searched using divergent keywords including "disaster, health, emergency, management, risk, disaster medicine, and hazard." DRM evolution started with the emergence of civil defense during the last century. Although DRM was initially focused on responses, currently, this concept includes disaster risk reduction (DRR) and disaster management. DRR includes prevention and mitigation, and disaster management includes response and recovery measures. DRR considering underlying risk factors such as social factors, and focusing on participation of communities are important steps to be taken. [ABSTRACT FROM AUTHOR]

Background: Women are at higher risk of death during disasters due to physical, biological, psychological, and cultural differences. After a disaster, they experience more miscarriages, premature births, inadequate fetal growth, low birth weight, sexual violence, and unwanted pregnancies. This study aims to investigate the reproductive health status of women affected by the 2017 earthquake in Kermanshah, Iran. Materials and Methods: This descriptive cross-sectional study was conducted in 2018. The study population consists of women aged 15-49 years (Mean age=31.7 years) living in Sarpol-e Zahab, Javanrood, and Thalas Babajani towns in Kermanshah city affected by the earthquake in 2017. The questionnaire used for assessing the status of reproductive health in women was the Reproductive Health Assessment Questionnaire for Women of Reproductive Age, which has already been localized in Iran and its reliability and validity have been confirmed. Native Kurdish language experts completed the questionnaires on behalf of 396 participants. Descriptive statistics were used to describe the variables. Results: It was found that 42.4% of women complained of abnormal menstruation and 34.09% of limited menstrual hygiene materials. Sixty women were pregnant at the time of the earthquake, all of whom gave birth in hospital; two had miscarriages, two had premature births, and one had stillbirth. Urinary tract infection was the most common problem (21%) in pregnant women. Moreover, 48% of women used contraceptive methods after the earthquake, the most commonly used method was the use of contraceptive pills (23%). Access to contraception methods was difficult for 14.4% of them after the earthquake. Furthermore, 25% had experienced violence after the earthquake; of these, 30 reported physical violence, 86 verbal violence, and 13 sexual violence. Conclusion: The control of pregnancy and safe delivery in earthquake-affected areas of Kermanshah is relatively acceptable; however, the provision of reproductive health services seems to be challenging. It is recommended to pay attention to the menstrual hygiene of women and regular distribution of contraceptives (despite the current population growth plan), address sexual acts of violence, and develop a protocol to support the victims. [ABSTRACT FROM AUTHOR]

Background: At the end of the 19th century, international communities have realized the necessity of global planning and cooperation. Accordingly, worldwide meetings have been organized for several years. This study aims to assess the achievement of predetermined objectives by international conferences in the field of risk management. Materials and Methods: The search for articles and documents was done using several keywords of "international meetings", "Sendai", "Hyogo", and "Yokohama" in Scopus, Web of Science, PubMed, Cochrane Library, Science Direct, Google Scholar databases. Also, the risk management domain websites such as FEMA, UNISDR, and EM-Date were searched. Results: Three Disaster World Conferences have been organized, hosted by Japan: Yokohama 1994, Kobe 2005, and Sendai 2015. They proposed strategies and prioritized actions for managing disaster risk, reducing the risk of disasters, and coping with disasters. In the second and third conferences, as requested by the United Nations (UN General Assembly), the UN Office for Disaster Risk Reduction (UNISDR) helped as the coordinating body. Conclusion: Reducing the risks of disasters is a global issue, which needs international cooperation. Therefore, all countries should take steps to achieve disaster risk reduction goals. Since declaraions, documents, resolutions, and conferences do not impose an obligation on countries in this regard, the success rate of the programs is dependent on voluntary international cooperation. Moreover, while we do not expect that outcomes of these international agreements related to disaster risk reduction be achieved at the scheduled time plan, strengthening the international cooperation of the countries to facilitate the improvement of actions and programs would be effective. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology using wavelet packet transform, principal component analysis, and neural networks in order to generate artificial critical aftershock accelerograms which are compatible with the response spectra. This procedure uses the learning abilities of neural networks, principal component analysis as a dimension reduction technique, and decomposing capabilities of wavelet packet transform on consecutive earthquakes. In fact, the proposed methodology consists of two steps and expands the knowledge of the inverse mapping from mainshock response spectrum to aftershock response spectrum and aftershock response spectrum to wavelet packet transform coefficients of the aftershocks. This procedure results in a stochastic ensemble of response spectra of aftershock (first step) and corresponding wavelet packet transform coefficients (second step) which are then used to generate the aftershocks through applying the inverse wavelet packet transform. Finally, in order to demonstrate the effectiveness of the proposed method, three examples are presented in which recorded critical successive ground motions are used to train and test the neural networks. [ABSTRACT FROM AUTHOR]

The current paper introduces a new approach for development of damage index to obtain the maximum damage in the reinforced concrete frames caused by as-recorded single and consecutive earthquakes. To do so, two sets of strong ground motions are selected based on maximum and approximately maximum peak ground acceleration (PGA) from "PEER" and "USGS" centers. Consecutive earthquakes in the first and second groups, not only occurred in similar directions and same stations, but also their real time gaps between successive shocks are less than 10 minutes and 10 days, respectively. In the following, a suite of six concrete moment resisting frames, including 3, 5, 7, 10, 12 and 15 stories, are designed in OpenSees software and analyzed for more than 850 times under two groups of as-recorded strong ground motion records with/without seismic sequences phenomena. The idealized multilayer artificial neural networks, with the least value of Mean Square Error (MSE) and maximum value of regression (R) between outputs and targets were then employed to generate the empirical charts and several correction equations for design utilization. To investigate the effectiveness of the proposed damage index, calibration of the new approach to existing real data (the result of Park-Ang damage index 1985), were conducted. The obtained results show good precision of the developed ANNs-based model in predicting the maximum damage of regular reinforced concrete frames. [ABSTRACT FROM AUTHOR]

A large main shock may consist of numerous aftershocks with a short period. The aftershocks induced by a large main shock can cause the collapse of a structure that has been already damaged by the preceding main shock. These aftershocks are important factors in structural damages. Furthermore, despite what is often assumed in seismic design codes, earthquakes do not usually occur as a single event, but as a series of strong aftershocks and even fore shocks. For this reason, this study investigates the effect and potential of consecutive earthquakes on the response and behavior of concrete structures. At first, six moment resisting concrete frames with 3, 5, 7, 10, 12 and 15 stories are designed and analyzed under two different records with seismic sequences from real and artificial cases. The damage states of the model frames were then measured by the Park and Ang's damage index. From the results of this investigation, it is observed that the sequences of ground motions can almost double the accumulated damage and increased response of structures. Therefore, it is certainly insufficient to ignore this effect in the design procedure of structures. Also, the use of artificial seismic sequences as design earthquake can lead to nonconservative prediction of behavior and damage of structures under real seismic sequences [ABSTRACT FROM AUTHOR]