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Technological advancements and the appearance of low-cost Raspberry Shake seismographs have enabled the development of citizen science seismic networks in many areas worldwide. These networks can help reduce seismic risk and increase citizens' understanding of seismology and earthquakes. Such a network exists in Bucharest, one of the cities in Europe that are struck and affected by strong Vrancea earthquakes. The paper aims to show that data from such networks can be used in both outreach programs and research studies. There are presented, for the first time, seismic observations collected over two years beginning in the summer of 2020 in the Bucharest area based on the low-cost seismometers from the citizen science Raspberry Shake network. A significant number of earthquakes from the Vrancea region were recorded by the Bucharest Raspberry Shake Seismic Network (BRSSN). Some of them were felt by Bucharest inhabitants. The National Institute for Earth Physics in Magurele (Romania) organizes educational events that promote geosciences among the population and presents the tools at its disposal for a better understanding of earthquakes and their effects, contributing this way to the development of the concept of citizen science. Citizens are the first witnesses to seismic events and the citizen science seismic network provides them with the first direct information about the event via web apps available for any internet-connected device. Their involvement as non-professional participants helps in providing data for scientists via questionnaire forms to improve scientific research for earthquake assessment. Since citizen seismometers are installed in urban areas, an analysis of the ambient seismic noise (ASN) was performed in addition to the analysis of recorded seismic events. The analysis indicates that the level of seismic noise is mainly controlled by human activities. At the same time, for one citizen seismometer installed in a school in Bucharest, the results show patterns of noise variations due to students' activity.
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In this paper, we present and demonstrate that the implementation of an efficient Project Management Strategy has effectively contributed in a safe and successful completion of a very complex 3D OBN Seismic Survey in congested Oil fields. Thus, delivering high quality data on schedule and within the predetermined budget at the full satisfaction of all involved parties and stakeholders. Strong commitment to HSSE Standards and working as an integrated One-Team with full collaboration and continuous communication between all the Team members are among the main Success Factors of the 3D seismic survey which was carried out during the critical period of COVID-19. Moreover, the deployment of experienced personnel, advanced and reliable Technologies with adequate equipment have also extended the efficiency of this OBN 3D seismic survey. Preliminary results of 3D seismic data processing, interpretation and reservoir characterization are also briefly presented and discussed as a clear enhancement of data quality was already observed compared to the legacy 3D OBC data set. A fast track small 3D cube was successfully processed as an utmost and urgent priority for appraisal well selection, design and drilling. Copyright © 2023, Society of Petroleum Engineers.
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The Port of San Diego's B Street Pier facility (Pier) is the busiest cruise terminal in the City of San Diego with over a hundred ship calls annually (pre-COVID). The Pier is an approximately 9.4-acre bulkhead faced mole extending about 1,000 ft into San Diego Bay and approximately 400 ft wide. On the three offshore sides of the bulkheaded mole are marginal pile supported wharfs constructed in 1923. The upland side of the mole is a concrete gravity seawall constructed in 1900. The mole soils consist of hydraulically placed dredge spoils and are susceptible to liquefaction.The existing Pier containment walls are deemed inadequate for seismic loading, mainly due to the presence of liquefiable materials both in front of and behind the existing containment wall. A solution consisting of an improved Deep Soil Mixing (DSM) zone coupled with the installation of a new steel sheet bulkhead was selected to retrofit and upgrade the Pier to current seismic standards. A key aspect of the design was to minimize loading induced from the wharf onto the existing curtain wall during an earthquake. The DSM zone is intended to serve a triple purpose, that is to improve shear strength of the soils behind the curtain wall, to mitigate the impact of liquefaction, and to provide sufficient bearing for potential future lightly loaded structures which may be constructed on the Pier. To obtain a cost-effective design and limit the DSM zone extents, the design also needed to limit the seismic load contributions to the DSM from the marginal wharves during seismic conditions. A development plan consisting of a multi-phased construction plan was determined to meet the Port's capital improvement needs and budget. Phase I development will install the DSM zone and steel sheet pile bulkhead along the south and west face of the mole. Future work will include wharf pile and deck replacement along with completing curtain wall replacement along the north face of the mole. This paper presents the geotechnical design challenges and considerations associated with the design of the DSM and sheet pile system comprising Phase I of the development plan. Key aspects of the geotechnical design included the selection of appropriate liquefaction resistance of the DSM improved zone, designing for the lateral spread of the slope in front of the curtain wall, assessment of stability and deformation of the proposed sheet pile, and the determination of the seismic earth pressures. © ASCE.
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May 15-19, 2022 Francavilla al Mare (Chieti), ITALYIntroductionThis Proceedings of the Journal of Physics: Conference Series contains a subset of papers presented at the 10th International Conference on Inverse Problems in Engineering (ICIPE), hosted by the Department of Industrial and Information Engineering and Economics, University of L'Aquila, Italy, and held in Francavilla al Mare (Chieti), May 15 – 19, 2022.Due to Coronavirus emergency and to protect the health and safety to all our participants, the 10th Edition, scheduled during May 18-21, 2020, and then May 16-20, 2021, was postponed to May 15-19, 2022, and termed as ICIPE 22.Since the first ICIPE in 1993, this conference has served as the main international venue for collaboration and interaction between applied mathematicians who develop inverse analysis tools, and engineers who use these tools in many different disciplines of science such as manufacturing and machining processes, medical imaging, oil exploration, radar, sonar and seismology, space applications, non-destructive testing and so on. The 2022 meeting continued this tradition, with more than 50 delegates from many sub-disciplines of engineering, science, and applied mathematics. The number of participants was lower than the standard number of 80 – 120 due to both covid travel restrictions in some Asian and American countries and conflict in Ukraine.List of Dedication, References, Organizing Committee, Local Committee, Scientific Committee, List of Registrants, Sponsors and Logos are available in this pdf.
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On November 26th, 2018, the InSight spacecraft successfully landed on Mars after a 6-month journey. After a long deployment and commissioning phase, the SEIS (Seismic Experiment for Interior Structure) instrument was ready to monitor seismic events on the Elysium Planitia plain on the surface of Mars, coupled with the APSS (Auxiliary Payload Sensor Suite) weather station equipped with a magnetometer, wind sensors, and a pressure sensor. The InSight mission goal is to characterize the deep interior structure of Mars, including the thickness and structure of the crust, the composition and structure of the mantle, and the size of the core. Its nominal duration of two years (2019–2020) has yielded unprecedented results with the detection of the first Martian seismic events ever recorded, and the in-depth characterization of its atmosphere with the best weather station ever deployed on Mars. InSight has collected an outstanding amount of high-quality measurements that the scientific community will spend many years analyzing. The extended mission has started and covers the years 2021 and 2022. This paper will describe the operations of the SEIS experiment on Mars since landing, as well as the challenges of operating this instrument. Energy becomes increasingly limited for payloads on Mars due to a significant amount of dust accumulated on the solar panels and the many dust storms in the Martian atmosphere. A new activity was decided for the extended mission in 2021 which consisted in burying the seismometer cable (or tether) with Martian regolith collected locally using the robotic arm, in order to reduce the seismic noise from that subsystem. Preparation activities, testing, results, associated challenges and lessons learned will be presented. Moreover, the paper will address the challenges faced in carrying out operations with COVID-related constraints, as finding oneself operating a seismometer on Mars from home can be challenging. Finally, management of periods of solar conjunctions, during which communication between Earth and Mars is unavailable, will be addressed. © 2022 IAA
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Earth's surface is constantly vibrating due to natural processes inside and human activities on the surface of the Earth. These vibrations form the ambient seismic fields that are measured by sensitive seismometers. Compared with natural processes, anthropogenic vibrations dominate the seismic measurements at higher frequency bands, demonstrate clear temporal and cyclic variability, and are more heterogeneous in space. Consequently, urban ambient seismic fields are a rich information source for human activity monitoring. Improving from the conventional energy-based seismic spectral analysis, we utilize advanced signal processing techniques to extract the occurrence of specific urban activities, including motor vehicle counts and runner activities, from the high-frequency ambient seismic noise. We compare the seismic energy in different frequency bands with the extracted activity intensity at different locations within a one-kilometer radius and highlight the high-resolution information in the seismic data. Our results demonstrate the intense heterogeneity in a highly developed urban space. Different sectors of urban society serve different functions and respond differently when urban life is severely disturbed by the impact of the COVID-19 pandemic in 2020. The anonymity of seismic data enabled an unprecedented spatial and temporal resolution, which potentially could be utilized by government regulators and policymakers for dynamic monitoring and urban management.
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Dynaslope Project, a government-funded program implemented by the Philippine Institute of Volcanology and Seismology (PHIVOLCS), develops and deploys an early warning system (EWS) for deep-seated landslides. It uses landslide sensor technology and community involvement in its EWS implementation in 50 sites all over the country. As the pandemic altered people’s modes of communication, it is important to understand how these changes relate to communicating landslide early warning information (LEWI). This research answered: How can the Dynaslope Project effectively communicate landslide risk during the COVID-19 pandemic? Specifically, it a) identified their preferred communication channels and tools during the pandemic, b) enumerated the stakeholders’ perceived participation and communication barriers, and c) measured the degree of trust of the stakeholders in the Project, the LEWI it released, and other key messages. This research was guided by the Actor-Network Theory and the concept of co-orientation which posited that, instead of a single entity defining a network or a system, it was the interactions between people, objects, and institutions that created a collective network and continuously negotiated a coherent understanding. The study employed a descriptive quantitative methodology. It used stratified random sampling to select the participants. Among the major findings include the stakeholders’ preference for offline communication like SMS and calls, the presence of communication and participation barriers including weak or no phone reception and limited access to up-to-date communication devices and the internet, and a high level of trust in the Dynaslope Project because it was implemented by a science-based national agency PHIVOLCS.
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Structural Engineering is an field of study that relies heavily on students' ability to visualize. Due to the scale of structural projects (e.g. bridges, buildings), it is not possible to provide students hands-on experiences manipulating and handling structural elements. Bringing students to the construction site is one of the most effective ways of reinforcing the subject matter as well as instilling a sense of awe and motivation for academic progress. However, the scheduling of field trips is very difficult due to students' academic and work schedules along with changes in site access due to COVID-19. San Francisco State University's Virtual Reality Engineering Program (VR Engine) was born out of a necessity to apply technology to advance efforts to engage and motivate students through inclusive teaching. This work in progress is using VR to develop immersive experiences to expand structural engineering students' perspectives and create interactive exercises to reinforce course material. As this work is being done in collaboration with the Computer Science department, this work also serves as an excellent opportunity to further research related to human-technology interfacing. VR is an emerging and affordable technology that immerses users in an artificial interactive environment using visual and auditory stimulation along with controllers for active engagement. Current efforts are utilizing common industry software, e.g., SAP2000 and Revit, to develop structural models and expand their potential through VR development using toolkits such as Unity. The VR exercises currently under development are generating structural systems to expose students to seismic technology, including seismic isolation. Through the implementation of these VR exercises, we aim to increase students' engagement and material comprehension in upper division structural engineering courses. © American Society for Engineering Education, 2022
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Reinforced concrete (RC) elements suffer continuous deterioration across their lifetime from in-situ aggressive environmental factors. Spiral reinforcing corrodes preferentially to longitudinal reinforcing, due to the smaller amount of protective cover concrete. Therefore, identifying the true shear resistance of a RC member in its deteriorated state is a critical component that must be addressed when assessing the seismic reliability of a structure. This research addresses the issue of chloride-induced corrosion damage in RC circular bridge piers, specifically focusing on the degradation rate of the seismic shear capacity. Twenty-two columns in total are to be tested in this experimental program. Three distinct damage levels are obtained through artificial corrosion simulation using two variations of the im-pressed-current technique. Effects of spiral spacing, diameter and volumetric ratio are also considered in this experimental work. Two current densities are induced: 200 μA/cm2 and 300 μA/cm2. Due to continual delays with Covid-19 restrictions, no results are yet available to discuss. © 2021, fib. The International Federation for Structural Concrete. All rights reserved.
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Structural health monitoring (SHM) has been recognized as a useful tool for experimentally assessing the structural behavior of historical buildings over time. If monitoring is performed continuously and for a long time, it allows to evaluate variations in the building’s dynamic response to external factors. The main goal is to estimate the dynamic response of the monitored buildings to daily stresses produced by environmental and anthropogenic factors (variations in ambient temperature and humidity, wind velocity, vibrations produced by vehicular traffic or other anthropogenic noise sources including visitors, service staff, etc.) to distinguish ordinary fluctuations in the buildings’ response from other anomalous behavior. Continuous monitoring also makes it possible to assess the impact of extraordinary events such as extreme weather events, earthquakes, excavations, cultural events involving many people nearby the monitored buildings. Some examples from the authors’ many monitoring campaigns on monuments located in different urban environments are presented. In particular, the effect on one of the monitored buildings of the drastic reduction of seismic noise during the SarsCov2 pandemic lockdown is investigated. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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Seismometers continuously record a wide range of ground movements not caused by earthquake activity, but rather generated by human activities such as traffic, industrial machinery functioning and industrial processes. In this Chapter we exploit seismic data to predict variations in Gross Domestic Product (GDP) for a set of States in the USA over the period from 2016 to 2021. We measure the noise generated at specific frequencies that are linked to human activity and use it as an indicator of economic activity. We show a remarkable reduction in seismic noise due to a slowdown in traffic and economic activities during the Corona economic crisis. Our results point at seismic data as a valuable source of information that can be used for monitoring regional and national economies. © 2022 by Emerald Publishing Limited.
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Under the severe COVID-19 infection circumstance as rapidly spreading in JAPAN since March 2020, we conducted 2-D land seismic survey in residential area, Niigata, JAPAN from November to December 2020 with necessary infection prevention measures. We set the criteria for the survey start propriety in advance and discussed about the survey implementation with related parties. We also obtained the understanding about this survey from local governments and residents before the survey start. During seismic survey, we took two types of original infection prevention measures as “Enclosure” and “Separation”, in addition to basic measures indicated by guidelines of the Japanese government. “Enclosure” measures aimed to prevent coronavirus from entering inside of the survey site. “Separation” measures were risk diversification of spreading coronavirus in the survey site. By planning and thoroughly adhering original countermeasures that matched the survey area COVID-19 status, we were able to complete the survey in the planned duration without interrupted the survey. In this paper, we introduce our original on-site infection prevention measures “Enclosure” and “Separation” and discuss how to manage the risk of COVID-19 infection at the seismic survey site. © (2021) by the European Association of Geoscientists & Engineers (EAGE)All rights reserved.
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The World of today is suffering from novel coronavirus (nCOV2). This is a respiratory infectious disease that has affected the entire globe. This respiratory infection is first originated in Wuhan, China. Today, it has many variants like the “United Kingdom (UK) variant called B.1.1.7,” “South African variant is called B.1.351,” “Brazilian variant is known as P.1,” etc. In this research work, we will discuss the Indian scenario to tackle nCOV2. We will also present an engineering student’s perspective to detect changes developed in the patient’s chest suffering from nCOV2 employing statistical methods. Among all the statistical techniques, GLCM-based texture analysis-based technique has gained popularity due to its diverse applications. It is used in many applications like remote sensing, image processing, biomedical applications, seismic data analysis. Thus in this research work, this methodology is used various changes in the before and after images of the patient suffering from the novel coronavirus. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
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Seismographs record earthquakes and also record various types of noise, including anthropogenic noise. In the present study, we analyse the influence of the lockdown due to COVID-19 on the ground motion at CSIR-NGRI HYB Seismological Observatory, Hyderabad. We analyse the noise recorded a week before and after the implementation of lockdown by estimating the probability density function of seismic power spectral density and by constructing the daily spectrograms. We find that at low frequency (<1 Hz), where the noise is typically dominated by naturally occurring microseismic noise, a reduction of ~2 dB for secondary microseisms (7–3 s) and at higher frequency (1–10 Hz) a reduction of ~6 dB was observed during the lockdown period. The reduction in higher frequencies corresponding to anthropogenic noise sources led to improving the SNR (signal-to-noise ratio) by a factor of 2 which is the frequency bandwidth of the microearthquakes leading to the identification of microearthquakes with Ml around 3 from epicentral distances of 180 km.
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Quantifying the response of human activities to different COVID-19 measures may serve as a potential way to evaluate the effectiveness of the measures and optimize measures. Recent studies reported that seismic noise reduction caused by less human activities due to COVID-19 lockdown had been observed by seismometers. However, it is difficult for current seismic infrastructure in urban cities to characterize spatiotemporal seismic noise during the postCOVID-19 lockdown because of sparse distribution. Here we show key connections between progressive COVID-19 measures and spatiotemporal seismic noise changes recorded by a distributed acoustic sensing (DAS) array deployed in State College, PA. Our results shows that DAS recordings using city-wide fiber optics could provide a way for quantifying the impact of COVID-19 measures on human activities in city blocks. © 2021 Society of Exploration Geophysicists First International Meeting for Applied Geoscience & Energy
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Urban activities in megacities around the world are not only the most severely impacted by the COVID-19 pandemic, but also the most consequential for the effectiveness of the mitigation measures. Therefore, monitoring and understanding the realtime changes of different sectors of an urban society is vital for policy making and dynamic pandemic management. By analyzing the high-frequency seismic signals, we separate the motor vehicle signal and the runner signal from the environment and background noise. We quantify the impact of the pandemic and its corresponding mitigation measures as traffic flow at nonessential workplaces, essential workplaces, and recreational areas. Enabled by the anonymity of seismic data, our study achieves an unprecedented spatial and temporal resolution that is pivotal to understand the heterogeneity and evolution of pandemic responses in different sectors of an urban society. The rich seismic-derived information provide a unique opportunity for realtime urban activity monitoring and dynamic policy making to ensure a successful pandemic mitigation while minimizing negative impacts on urban lifestyle. © 2021 Society of Exploration Geophysicists First International Meeting for Applied Geoscience & Energy