scholarly journals Investigation of the limits of high-definition muography for observation of Mt Sakurajima

2018 ◽  
Vol 377 (2137) ◽  
pp. 20180135 ◽  
Author(s):  
László Oláh ◽  
Hiroyuki K. M. Tanaka ◽  
Gergő Hamar ◽  
Dezső Varga
Keyword(s):  
Multiple Scattering ◽  
Large Scale ◽  
Cosmic Ray ◽  
Average Density ◽  
Muon Flux ◽  
Observation System ◽  
High Definition ◽  
Proportional Chamber ◽  
Density Values ◽  
Density Map

A multi-wire proportional chamber-based muo- graphy observatory is under development for the monitoring of the internal structure of Mt Sakurajima in Kyushu, Japan. We investigated the limits of large-scale and high-definition muography. We adjusted the parameters of a modified Gaisser model and found that the spectral index of γ  =  − 2.64 and normalization factor of C  = 0.66 reproduce more accurately the measured fluxes than the original parameters at large thickness. A thickness and zenith angle-dependent correction is suggested to the measured muon flux due to the energy cut which is introduced to suppress the background particles. The multiple scattering of muons was simulated across the standard rock and sea-level atmosphere up to the distance of 5 km. We found that multiple scattering decreases from 10 mrad to 4 mrad across the rock due to the decrease in the steepness of muon spectra. The multiple scattering falls down to about 2 mrad after the object in the atmosphere due to the increase in observed arrival zenith angles. The 2 m 2 sized multi-wire proportional chamber-based Muographic Observation System (MMOS) was operating between February and June 2018. Three tracking systems operated reliably with tracking efficiencies of above 95%. The muon flux has been measured correctly down to 10 −3  m −2  sr −1  s −1 . The average density map of Mt Sakurajima has been measured with angular resolution of 12 mrad × 12 mrad (spatial resolution of 34 m × 34 m from the distance of 2.8 km). The average density values were found between 1.4 and 2 g cm −3 , except at the crater regions where lower densities were observed. This article is part of the Theo Murphy meeting issue ‘Cosmic-ray muography’.

scholarly journals Muographic monitoring of hydrogeomorphic changes induced by post-eruptive lahars and erosion of Sakurajima volcano

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
László Oláh ◽  
Hiroyuki K. M. Tanaka ◽  
Gergő Hamar
Keyword(s):  
Cosmic Ray ◽  
Volcanic Hazards ◽  
Observation System ◽  
Passive Imaging ◽  
Sakurajima Volcano ◽  
Proportional Chamber ◽  
Gravity Driven ◽  
Continuous Deposition ◽  
Mass Increase

AbstractPost-eruptive destabilization of volcanic edifices by gravity driven debris flows or erosion can catastrophically impact the landscapes, economies and human societies surrounding active volcanoes. In this work, we propose cosmic-ray muon imaging (muography) as a tool for the remote monitoring of hydrogeomorphic responses to volcano landscape disturbances. We conducted the muographic monitoring of Sakurajima volcano, Kyushu, Japan and measured continuous post-eruptive activity with over 30 lahars per year. The sensitive surface area of the Multi-Wire-Proportional-Chamber-based Muography Observation System was upgraded to 7.67 m$$^2$$ 2 ; this made it possible for the density of tephra within the crater region to be measured in 40 days. We observed the muon flux decrease from 10 to 40% through the different regions of the crater from September 2019 to October 2020 due to the continuous deposition of tephra fallouts. In spite of the long-term mass increase, significant mass decreases were also observed after the onsets of rain-triggered lahars that induced the erosion of sedimented tephra. The first muographic observation of these post-eruptive phenomena demonstrate that this passive imaging technique has the potential to contribute to the assessment of indirect volcanic hazards.

scholarly journals Geophysical Properties of Precambrian Igneous Rocks in the Gwanin Vanadiferous Titanomagnetite Deposit, Korea

Minerals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1031
Author(s):  
Seungwook Shin ◽  
Seongjun Cho ◽  
Euijun Kim ◽  
Jihyun Lee
Keyword(s):  
Large Scale ◽  
Laboratory Experiments ◽  
Mineral Exploration ◽  
Average Density ◽  
Igneous Rocks ◽  
Magmatic Differentiation ◽  
Redox Flow Batteries ◽  
Geophysical Surveys ◽  
Density Values ◽  
Vanadium Redox

Precambrian igneous rocks (851–873 Ma) occur in Pocheon City, Korea. These rocks —crystallized during magmatic differentiation—formed vanadiferous titanomagnetite (VTM) deposit. Vanadium is a crucial element in vanadium redox flow batteries that are most appropriate for large-scale energy storage systems. We investigated the VTM deposit to evaluate its size and the possible presence of a hidden orebody. We demonstrated laboratory experiments of density, susceptibility, resistivity, and chargeability of the Precambrian igneous rocks to enhance the interpretation accuracy of geophysical surveys. The rocks consisting of underground ore (UO), discovered ore (DO), gabbro (GA), monzodiorite (MD), and quartz monzodiorite (QMD) were sampled from drilling cores and outcrops. The average density values were UO: 4.57 g/cm3, DO: 3.63 g/cm3, GA: 3.26 g/cm3, MD: 3.18 g/cm3, and QMD: 2.85 g/cm3. The average susceptibility values were UO: 0.8175 SI, DO: 0.2317 SI, GA: 0.0780, MD: 0.0126 SI, and QMD: 0.0007. The average resistivity values were UO: 2 Ωm, DO: 36 Ωm, GA: 257 Ωm, MD: 4571Ωm, and QMD: 7801 Ωm. The chargeability values were UO: 143 mV/V, DO: 108 mV/V, GA: 79 mV/V, MD: 42 mV/V, and QMD: 9 mV/V. We found that the properties of the mineralized rocks are considerably different from those of the surrounding rocks. This result may facilitate the mineral exploration of VTM deposits.

Muographic Observation of Density Variations in the Vicinity of Minami-Dake Crater of Sakurajima Volcano

2019 ◽  
Vol 14 (5) ◽  
pp. 701-712
Author(s):  
László Oláh ◽  
Hiroyuki K. M. Tanaka ◽  
Gergő Hamar ◽  
Dezső Varga ◽  
◽  
...  
Keyword(s):  
Data Collection ◽  
Mass Density ◽  
Cosmic Ray ◽  
Total Surface Area ◽  
Average Density ◽  
Observation System ◽  
Length Variation ◽  
Sakurajima Volcano ◽  
Data Collection Period ◽  
Collection Period

Muography is an innovative imaging technique used for inspecting and monitoring density-length variations of large-sized natural or human-made objects based on the measurement of the absorption rate of cosmic-ray muons. The first large-sized, high-resolution muography observatory based on Multi-Wire Proportional Chamber (MWPC) technology is being developed to monitor the mass density variations in the vicinity of Minami-dake crater of Sakurajima volcano. We found that the track rates provided by five ongoing tracking systems with a total surface area of 4 m2 are stable within ±3% from the backward direction, which demonstrates that the MWPC-based Muographic Observation System (MMOS) is applicable for the detection of average density variations above 2%, which is well below the practical limit of 5%. We quantified the time resolution of the designed muography observatory by modeling the muon flux across the volcano; the average density-length variation of 5 (10)% is expected to be detected within 5–20 (2–8) days at a 1σ (68%) confidence level (CL) with an MMOS orientation of 10.86° above the horizon. An automated analysis framework was developed as a data base for raw data reconstruction, analysis, and preparation, and which is accessible via web-server. We observed a more than 2σ CL decrease in average density across the West side of Crater A during the ongoing data collection period. The observed density decrease suggests that the amount of material has decreased inside Crater A due to the consecutive eruptions of Minami-dake during the data collection period from November 30, 2018 to January 11, 2019.

scholarly journals Large-scale anisotropy of the cosmic-ray muon flux in Kamiokande

1997 ◽  
Vol 56 (1) ◽  
pp. 23-26 ◽  
Author(s):  
K. Munakata ◽  
T. Kiuchi ◽  
S. Yasue ◽  
C. Kato ◽  
S. Mori ◽  
...  
Keyword(s):  
Large Scale ◽  
Cosmic Ray ◽  
Muon Flux

New Models of Content Creation and Scholarship at the Intersection of Library Spaces, Technologies, and Expertise

2018 ◽  
Author(s):  
Mike Nutt ◽  
Gregory Raschke
Keyword(s):  
Large Scale ◽  
Interactive Media ◽  
Scholarly Communication ◽  
Three Dimensions ◽  
Organizational Capabilities ◽  
High Definition ◽  
Content Creation ◽  
Full Life Cycle ◽  
Digital Scholarship ◽  
Digital Objects

Library spaces that blend collaboration areas, advanced technologies, and librarian expertise are creating new modes of scholarly communication. These spaces enable scholarship created within high-definition, large-scale visual collaborative environments. This emergent model of scholarly communication can be experienced within those specific contexts or through digital surrogates on the networked Web. From experiencing in three dimensions the sermons of John Donne in 1622 to interactive media interpretations of American wars, scholars are partnering with libraries to create immersive digital scholarship. Viewing the library as a research platform for these emergent forms of digital scholarship presents several opportunities and challenges. Opportunities include re-engaging faculty in the use of library space, integrating the full life-cycle of the research enterprise, and engaging broad communities in the changing nature of digitally-driven scholarship. Issues such as identifying and filtering collaborations, strategically managing staff resources, creating surrogates of immersive digital scholarship, and preserving this content for the future present an array of challenges for libraries that require coordination across organizations. From engaging and using high-technology spaces to documenting the data and digital objects created, this developing scholarly communication medium brings to bear the multifaceted skills and organizational capabilities of libraries.

scholarly journals CNN-Based Classifier as an Offline Trigger for the CREDO Experiment

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4804
Author(s):  
Marcin Piekarczyk ◽  
Olaf Bar ◽  
Łukasz Bibrzycki ◽  
Michał Niedźwiecki ◽  
Krzysztof Rzecki ◽  
...  
Keyword(s):  
Wavelet Transforms ◽  
Exploratory Study ◽  
Large Scale ◽  
Morphological Difference ◽  
Cosmic Ray ◽  
Input Image ◽  
Image Features ◽  
The Earth ◽  
Cmos Sensor ◽  
Competition Process

Gamification is known to enhance users’ participation in education and research projects that follow the citizen science paradigm. The Cosmic Ray Extremely Distributed Observatory (CREDO) experiment is designed for the large-scale study of various radiation forms that continuously reach the Earth from space, collectively known as cosmic rays. The CREDO Detector app relies on a network of involved users and is now working worldwide across phones and other CMOS sensor-equipped devices. To broaden the user base and activate current users, CREDO extensively uses the gamification solutions like the periodical Particle Hunters Competition. However, the adverse effect of gamification is that the number of artefacts, i.e., signals unrelated to cosmic ray detection or openly related to cheating, substantially increases. To tag the artefacts appearing in the CREDO database we propose the method based on machine learning. The approach involves training the Convolutional Neural Network (CNN) to recognise the morphological difference between signals and artefacts. As a result we obtain the CNN-based trigger which is able to mimic the signal vs. artefact assignments of human annotators as closely as possible. To enhance the method, the input image signal is adaptively thresholded and then transformed using Daubechies wavelets. In this exploratory study, we use wavelet transforms to amplify distinctive image features. As a result, we obtain a very good recognition ratio of almost 99% for both signal and artefacts. The proposed solution allows eliminating the manual supervision of the competition process.

A gravity model of the basement structure in the Santa Maria Basin, California

Geophysics ◽  
1986 ◽  
Vol 51 (5) ◽  
pp. 1127-1140 ◽  
Author(s):  
Paul M. Kieniewicz ◽  
Bruce P. Luyendyk
Keyword(s):  
Short Wavelength ◽  
Large Scale ◽  
Bouguer Anomaly ◽  
Three Dimensional ◽  
Average Density ◽  
Structure Model ◽  
Basement Structure ◽  
Santa Maria Basin ◽  
Clastic Rocks ◽  
Santa Maria

The Santa Maria Basin in southern California is a lowland bounded on the south by the Santa Ynez River fault and on the northeast by the Little Pine‐Foxen Canyon‐Santa Maria River faults. It contains Neogene sedimentary rocks which rest unconformably on a basement of Cretaceous and older clastic rocks. Analysis of over 4 000 gravity stations obtained from the Defense Mapping Agency suggests that the Bouguer anomaly contains a short‐wavelength component arising from a variable‐density contrast between the basin’s Neogene units and the Cretaceous basement. A three‐dimensional inversion of the short‐wavelength component (constrained by wells drilled to basement) yields a structure model of the basement and the average density of the overlying sediments, assuming that the basement does not contain large‐scale density variations. The density anomalies modeled in the Neogene sediments, showing higher densities in the basin troughs, can be related to diagenetic changes in the silica facies of the Monterey and Sisquoc formations. The basement structure model shows the basin as composed of parallel ridges and troughs, trending west‐northwest and bounded by steep slopes interpreted as fault scarps. The basin is bounded on the west by a north‐south trending slope which may also represent a fault scarp.

Bridge Health Monitoring by Infrared Thermography

2019 ◽  
Author(s):  
Masato Matsumoto ◽  
Kyle Ruske
Keyword(s):  
Large Scale ◽  
Lessons Learned ◽  
High Definition ◽  
Bridge Health Monitoring ◽  
Large Scale Data ◽  
Concrete Bridge Decks ◽  
Federal Highway ◽  
Negative Impacts ◽  
Visual Confirmation ◽  
Inspection Data

<p>Condition ratings of bridge components in the Federal Highway Administration (FHWA)’s Structural Inventory and Appraisal database are determined by bridge inspectors in the field, often by visual confirmation or direct- contact sounding techniques. However, the determination of bridge condition ratings is generally subjective depending on individual inspectors’ knowledge and experience, as well as varying field conditions. There are also limitations to access, unsafe working conditions, and negative impacts of lane closures to account for. This paper describes an alternative method to obtaining informative and diagnostic inspection data for concrete bridge decks: mobile nondestructive bridge deck evaluation technology. The technology uses high- definition infrared and visual imaging to monitor bridge conditions over long-term (or desired) intervals. This combination of instruments benefits from rapid and large-scale data acquisition capabilities. Through its implementation in Japan over the course of two decades, the technology is opening new possibilities in a field with much untapped potential. Findings and lessons learned from our experience in the states of Virginia and Pennsylvania are described as examples of highway-speed mobile nondestructive evaluation in action. To validate the accuracy of delamination detection by the visual and infrared scanning, findings were proofed by physical sounding of the target deck structures.</p>

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