The "Arctic" region,where the North Pole occupies the center of the Arctic Ocean,has been affecting the environmental variation of the Earth from geological time to the present.However,the seismic activities...The "Arctic" region,where the North Pole occupies the center of the Arctic Ocean,has been affecting the environmental variation of the Earth from geological time to the present.However,the seismic activities in the area are not adequately monitored.Therefore,by conducting long term monitoring of seismic phenomenon as sustainable parameters,our understanding of both the tectonic evolution of the Earth and the dynamic interaction between the cryosphere and geosphere in surface layers of the Earth will increase.In this paper,the association of the seismicity and structure of the Arctic region,particularly focused on Eurasian continent and surrounding oceans,and its relationship with regional evolution during the Earth’s history is studied.The target areas cover representative tectonic provinces in the Eurasian Arctic,such as the wide area of Siberia,Baikal Rift Zone.Far East Russia,Arctic Ocean together with Greenland and Northern Canada.Based on discussion including characteristics of seismicity,heterogeneous structure of the crust and upper mantle,tectonic history and recent dynamic features of the Earth’s surface in the Arctic are summarized.展开更多
Characteristic features of infrasound waves observed in the Antarctic represent a physical interaction relating surface environment in the continental margin and surrounding Southern Ocean. Source location of several ...Characteristic features of infrasound waves observed in the Antarctic represent a physical interaction relating surface environment in the continental margin and surrounding Southern Ocean. Source location of several infrasound events is demonstrated by using combination of two array deployments along a coast of the Lützow-Holm Bay (LHB), East Antarctica, for data retrieving period in January-June 2015. These infrasound arrays being established in January 2013 clearly detected temporal variations in frequency content and propagation direction of the identified seven large events. Many of these sources are assumed to have cryoseismic origins;the ice-quakes associated with calving of glaciers, discharge of sea-ice, collision between sea-ice and icebergs around the LHB. Detail and continuous measurements of infrasound waves in the Antarctic are a proxy for monitoring regional environment as well as climate change in high southern latitude.展开更多
During the period from October 2014 to March 2015, a total number of 82 seismic tremors and 66 ice-quakes were identified in both three-component short-period seismographs (HES) and broadband seismographs (STS-1) at S...During the period from October 2014 to March 2015, a total number of 82 seismic tremors and 66 ice-quakes were identified in both three-component short-period seismographs (HES) and broadband seismographs (STS-1) at Syowa Station (SYO), Antarctica. Statistics of the number of these tremors indicated that many tremors were likely to occur when large increases in temperature and/or wind speed during the period. This implied that the rapid increase in temperature enhanced a melting speed of cryosphere environment with generating seismic energy;the tremors were also excited by stormy conditions, associated with interactive resonance between sea-ices and oceanic swells. The characteristic tremors of harmonic overtones with strong amplitudes were explained by repetitive sources, suggesting inter-glacial asperities such as the collision of icebergs and fast sea-ice, calving of glaciers/ice-streams at the coastal environment of Antarctica. These high amplitude tremors occurred independently from other majority types of events, characterized by non-linear, small amplitude and weak signals at the stormy condition and rapid increase in temperature.展开更多
Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East...Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East Antarctica. In order to examine a relationship between surface environments in particular cryosphere variation, the MODIS satellite images were utilized for comparison with the detected tremor events. Since a large volume of sea-ice was discharged during the April, together with several large icebergs passed through from the west to the east at northern edge of the fast sea-ice of LHB, it was expected to detect seismic tremors involving cryospehre dynamics. During the month, a total number of 49 tremor events including short duration ice shocks were identified. Majority of the events (N = 39) had their duration times more than 15 minutes, which were divided into both tremors and ice shocks on the basis of experienced definition at SYO. Cryospheric sources recorded by seismic tremors were classified into several origins (collision, calving, crevassing, crashing, etc.): “crevassing events” along the large cracks inside the fast sea-ice in LHB (04 April), “discharge events” of fast sea-ice from the Bay (07 April), “collision events” between iceberg and the edge of fast sea-ice (14 April), “crashing movement” between fragmentation of fast sea-ice and packed sea-ice (18 April), and other origins. In particular, strong amplitude tremors with harmonic overtones were assumed to be occurred independently from whether condition, because these overtone tremors were identified at less stormy days by comparison with infrasound data at SYO.展开更多
Phase identification procedures for teleseismic events at Syowa Station (69.0°S, 39.6°E;SYO), East Antarctica have been carried out since 1967 after the International Geophysical Year (IGY;1957-1958). Since ...Phase identification procedures for teleseismic events at Syowa Station (69.0°S, 39.6°E;SYO), East Antarctica have been carried out since 1967 after the International Geophysical Year (IGY;1957-1958). Since the development of INTELSAT telecommunication link, digital waveform data have been transmitted to the National Institute of Polar Research (NIPR) for the utilization of phase identification. Arrival times of teleseismic phases, P, PKP, PP, S, SKS have been detected manually and reported to the International Seismological Centre (ISC), and published by “JARE Data Reports” from NIPR. In this paper, hypocentral distribution and time variations for detected earthquakes are demonstrated over the last four decades in 1967-2010. Characteristics of detected events, magnitude dependency, spatial distributions, seasonal variations, together with classification by focal depth are investigated. Besides the natural increase in the occurrence of teleseismic events on the globe, a technical advance in the observing system and station infrastructure, as well as the improvement of procedures for reading seismic phases, could all combine to produce the increase in detection of events in last few decades. Variations in teleseismic detectability for longer terms may be possible by association with the meteorological environment and seaice spreading area around the Antarctic continent. Recorded teleseismic and local seismic signals have sufficient quality for many analyses on dynamics and structure of the Earth as viewed from Antarctica. The continuously recorded data are applied not only to lithospheric studies but also to the Earth’s deep interiors, as a significant contribution to the Federation of Digital Seismological Networks (FDSN) from high southern latitude.展开更多
Earthquakes are one of the natural disasters that pose a major threat to human lives and property. Earthquake prediction propels the construction and development of modern seismology;however, current deterministic ear...Earthquakes are one of the natural disasters that pose a major threat to human lives and property. Earthquake prediction propels the construction and development of modern seismology;however, current deterministic earthquake prediction is limited by numerous difficulties. Identifying the temporal and spatial statistical characteristics of earthquake occurrences and constructing earthquake risk statistical prediction models have become significant;particularly for evaluating earthquake risks and addressing seismic planning requirements such as the design of cities and lifeline projects based on the obtained insight. Since the 21 st century, the occurrence of a series of strong earthquakes represented by the Wenchuan M8 earthquake in 2008 in certain low-risk prediction areas has caused seismologists to reflect on traditional seismic hazard assessment globally. This article briefly reviews the development of statistical seismology, emphatically analyzes the research results and existing problems of statistical seismology in seismic hazard assessment, and discusses the direction of its development. The analysis shows that the seismic hazard assessment based on modern earthquake catalogues in most regions should be effective. Particularly, the application of seismic hazard assessment based on ETAS(epidemic type aftershock sequence)should be the easiest and most effective method for the compilation of seismic hazard maps in large urban agglomeration areas and low seismic hazard areas with thick sedimentary zones.展开更多
Characteristic infrasound waves observed at Antarctic stations demonstrate physical interaction involving environmental changes in the Antarctic continent and the surrounding oceans. A Chaparraltype infrasound sensor ...Characteristic infrasound waves observed at Antarctic stations demonstrate physical interaction involving environmental changes in the Antarctic continent and the surrounding oceans. A Chaparraltype infrasound sensor was installed at Syowa Station （SYO; 39°E, 69°S）, East Antarctica, as one of the projects of the International Polar Year （IPY2007-2008）. Data continuously recorded during the three seasons in 2008-2010 clearly indicate a contamination of the background oceanic signals （microbaroms） with peaks between 4 and 10 s observed during a whole season. The peak amplitudes of the microbaroms have relatively lower values during austral winters, caused by a larger amount of sea-ice extending around the Lutzow-Holm Bay near SYO, with decreasing ocean wave loading effects. Micro- baroms measurements are useful tool for characterizing ocean wave climate, complementing other oceanographic and geophysical data. A continuous monitoring by infrasound sensors in the Antarctic firmly contributes to the Comprehensive Nuclear-Test-Ban Treaty （CTBT） in the southern high latitude, together with the Pan-Antarctic Observations System （PAntOS） under the Scientific Committee on Antarctic Research （SCAR）. Detailed measurements of the infrasound waves in Antarctica, consequently, could be a new proxy for monitoring regional environmental change as well as the temporal climate variations in the polar regions.展开更多
Infrasound signals in Antarctica reflect physical interaction in the surface environments around the recorded area. In December 2015, an infrasound array by three sensors in the detectable frequency range of 0.1 - 200...Infrasound signals in Antarctica reflect physical interaction in the surface environments around the recorded area. In December 2015, an infrasound array by three sensors in the detectable frequency range of 0.1 - 200 Hz, combined with one broadband barometer was deployed at Jang Bogo Station, Terra Nova Bay, Antarctica. The two years of data by the broadband barometer contain characteristic signals that caused by surface environment nearby the station, mixing with local noises such as katabatic winds. Clear continuous signals by oceanic swells (microbaroms) were recorded with a predominant frequency of around 0.2 s. Variations of frequency context and amplitudes in the Power Spectral Density were considered as affected by sea-ice dynamics surrounding the Terra Nova Bay. Monitoring of microbaroms could contribute to understanding ocean wave climate, with other oceanographic, cryospheric and geophysical data in Antarctica. Infrasound data in Terra Nova Bay might be a new proxy for estimating environmental variations affected by global warming, cryosphere dynamics, together with volcanic eruptions in Victoria Land.展开更多
The use of machine learning in computational molecular design has great potential to accelerate the discovery of innovative materials.However,its practical benefits still remain unproven in real-world applications,par...The use of machine learning in computational molecular design has great potential to accelerate the discovery of innovative materials.However,its practical benefits still remain unproven in real-world applications,particularly in polymer science.We demonstrate the successful discovery of new polymers with high thermal conductivity,inspired by machine-learning-assisted polymer chemistry.This discovery was made by the interplay between machine intelligence trained on a substantially limited amount of polymeric properties data,expertise from laboratory synthesis and advanced technologies for thermophysical property measurements.Using a molecular design algorithm trained to recognize quantitative structure—property relationships with respect to thermal conductivity and other targeted polymeric properties,we identified thousands of promising hypothetical polymers.From these candidates,three were selected for monomer synthesis and polymerization because of their synthetic accessibility and their potential for ease of processing in further applications.The synthesized polymers reached thermal conductivities of 0.18–0.41 W/mK,which are comparable to those of state-of-the-art polymers in non-composite thermo-plastics.展开更多
Recent progress in material data mining has been driven by high-capacity models trained on large datasets.However,collecting experimental data(real data)has been extremely costly owing to the amount of human effort an...Recent progress in material data mining has been driven by high-capacity models trained on large datasets.However,collecting experimental data(real data)has been extremely costly owing to the amount of human effort and expertise required.Here,we develop a novel transfer learning strategy to address problems of small or insufficient data.This strategy realizes the fusion of real and simulated data and the augmentation of training data in a data mining procedure.For a specific task of grain instance image segmentation,this strategy aims to generate synthetic data by fusing the images obtained from simulating the physical mechanism of grain formation and the“image style”information in real images.The results show that the model trained with the acquired synthetic data and only 35%of the real data can already achieve competitive segmentation performance of a model trained on all of the real data.Because the time required to perform grain simulation and to generate synthetic data are almost negligible as compared to the effort for obtaining real data,our proposed strategy is able to exploit the strong prediction power of deep learning without significantly increasing the experimental burden of training data preparation.展开更多
The spread of data-driven materials research has increased the need for systematically designed materials property databases.However,the development of polymer databases has lagged far behind other material systems.We...The spread of data-driven materials research has increased the need for systematically designed materials property databases.However,the development of polymer databases has lagged far behind other material systems.We present RadonPy,an open-source library that can automate the complete process of all-atom classical molecular dynamics(MD)simulations applicable to a wide variety of polymeric materials.Herein,15 different properties were calculated for more than 1000 amorphous polymers.The MD-calculated properties were systematically compared with experimental data to validate the calculation conditions;the bias and variance in the MD-calculated properties were successfully calibrated by a machine learning technique.During the high-throughput data production,we identified eight amorphous polymers with extremely high thermal conductivity(>0.4 W∙m^(–1)∙K^(–1))and their underlying mechanisms.Similar to the advancement of materials informatics since the advent of computational property databases for inorganic crystals,database construction using RadonPy will promote the development of polymer informatics.展开更多
The automated stopping of a spectral measurement with active learning is proposed.The optimal stopping of the measurement is realised with a stopping criterion based on the upper bound of the posterior average of the ...The automated stopping of a spectral measurement with active learning is proposed.The optimal stopping of the measurement is realised with a stopping criterion based on the upper bound of the posterior average of the generalisation error of the Gaussian process regression.It is revealed that the automated stopping criterion of the spectral measurement gives an approximated X-ray absorption spectrum with sufficient accuracy and reduced data size.The proposed method is not only a proof-of-concept of the optimal stopping problem in active learning but also the key to enhancing the efficiency of spectral measurements for highthroughput experiments in the era of materials informatics.展开更多
基金supported by JSPS KAKENHI Grant Number 26241010(P.I.by Dr.Masaki Kanao)
文摘The "Arctic" region,where the North Pole occupies the center of the Arctic Ocean,has been affecting the environmental variation of the Earth from geological time to the present.However,the seismic activities in the area are not adequately monitored.Therefore,by conducting long term monitoring of seismic phenomenon as sustainable parameters,our understanding of both the tectonic evolution of the Earth and the dynamic interaction between the cryosphere and geosphere in surface layers of the Earth will increase.In this paper,the association of the seismicity and structure of the Arctic region,particularly focused on Eurasian continent and surrounding oceans,and its relationship with regional evolution during the Earth’s history is studied.The target areas cover representative tectonic provinces in the Eurasian Arctic,such as the wide area of Siberia,Baikal Rift Zone.Far East Russia,Arctic Ocean together with Greenland and Northern Canada.Based on discussion including characteristics of seismicity,heterogeneous structure of the crust and upper mantle,tectonic history and recent dynamic features of the Earth’s surface in the Arctic are summarized.
文摘Characteristic features of infrasound waves observed in the Antarctic represent a physical interaction relating surface environment in the continental margin and surrounding Southern Ocean. Source location of several infrasound events is demonstrated by using combination of two array deployments along a coast of the Lützow-Holm Bay (LHB), East Antarctica, for data retrieving period in January-June 2015. These infrasound arrays being established in January 2013 clearly detected temporal variations in frequency content and propagation direction of the identified seven large events. Many of these sources are assumed to have cryoseismic origins;the ice-quakes associated with calving of glaciers, discharge of sea-ice, collision between sea-ice and icebergs around the LHB. Detail and continuous measurements of infrasound waves in the Antarctic are a proxy for monitoring regional environment as well as climate change in high southern latitude.
文摘During the period from October 2014 to March 2015, a total number of 82 seismic tremors and 66 ice-quakes were identified in both three-component short-period seismographs (HES) and broadband seismographs (STS-1) at Syowa Station (SYO), Antarctica. Statistics of the number of these tremors indicated that many tremors were likely to occur when large increases in temperature and/or wind speed during the period. This implied that the rapid increase in temperature enhanced a melting speed of cryosphere environment with generating seismic energy;the tremors were also excited by stormy conditions, associated with interactive resonance between sea-ices and oceanic swells. The characteristic tremors of harmonic overtones with strong amplitudes were explained by repetitive sources, suggesting inter-glacial asperities such as the collision of icebergs and fast sea-ice, calving of glaciers/ice-streams at the coastal environment of Antarctica. These high amplitude tremors occurred independently from other majority types of events, characterized by non-linear, small amplitude and weak signals at the stormy condition and rapid increase in temperature.
文摘Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East Antarctica. In order to examine a relationship between surface environments in particular cryosphere variation, the MODIS satellite images were utilized for comparison with the detected tremor events. Since a large volume of sea-ice was discharged during the April, together with several large icebergs passed through from the west to the east at northern edge of the fast sea-ice of LHB, it was expected to detect seismic tremors involving cryospehre dynamics. During the month, a total number of 49 tremor events including short duration ice shocks were identified. Majority of the events (N = 39) had their duration times more than 15 minutes, which were divided into both tremors and ice shocks on the basis of experienced definition at SYO. Cryospheric sources recorded by seismic tremors were classified into several origins (collision, calving, crevassing, crashing, etc.): “crevassing events” along the large cracks inside the fast sea-ice in LHB (04 April), “discharge events” of fast sea-ice from the Bay (07 April), “collision events” between iceberg and the edge of fast sea-ice (14 April), “crashing movement” between fragmentation of fast sea-ice and packed sea-ice (18 April), and other origins. In particular, strong amplitude tremors with harmonic overtones were assumed to be occurred independently from whether condition, because these overtone tremors were identified at less stormy days by comparison with infrasound data at SYO.
文摘Phase identification procedures for teleseismic events at Syowa Station (69.0°S, 39.6°E;SYO), East Antarctica have been carried out since 1967 after the International Geophysical Year (IGY;1957-1958). Since the development of INTELSAT telecommunication link, digital waveform data have been transmitted to the National Institute of Polar Research (NIPR) for the utilization of phase identification. Arrival times of teleseismic phases, P, PKP, PP, S, SKS have been detected manually and reported to the International Seismological Centre (ISC), and published by “JARE Data Reports” from NIPR. In this paper, hypocentral distribution and time variations for detected earthquakes are demonstrated over the last four decades in 1967-2010. Characteristics of detected events, magnitude dependency, spatial distributions, seasonal variations, together with classification by focal depth are investigated. Besides the natural increase in the occurrence of teleseismic events on the globe, a technical advance in the observing system and station infrastructure, as well as the improvement of procedures for reading seismic phases, could all combine to produce the increase in detection of events in last few decades. Variations in teleseismic detectability for longer terms may be possible by association with the meteorological environment and seaice spreading area around the Antarctic continent. Recorded teleseismic and local seismic signals have sufficient quality for many analyses on dynamics and structure of the Earth as viewed from Antarctica. The continuously recorded data are applied not only to lithospheric studies but also to the Earth’s deep interiors, as a significant contribution to the Federation of Digital Seismological Networks (FDSN) from high southern latitude.
基金This work was supported by the National Natural Science Foundation of China(Grant No.U2039204)the National Key R&D Program of China(Grant No.2018YFC1504203).
文摘Earthquakes are one of the natural disasters that pose a major threat to human lives and property. Earthquake prediction propels the construction and development of modern seismology;however, current deterministic earthquake prediction is limited by numerous difficulties. Identifying the temporal and spatial statistical characteristics of earthquake occurrences and constructing earthquake risk statistical prediction models have become significant;particularly for evaluating earthquake risks and addressing seismic planning requirements such as the design of cities and lifeline projects based on the obtained insight. Since the 21 st century, the occurrence of a series of strong earthquakes represented by the Wenchuan M8 earthquake in 2008 in certain low-risk prediction areas has caused seismologists to reflect on traditional seismic hazard assessment globally. This article briefly reviews the development of statistical seismology, emphatically analyzes the research results and existing problems of statistical seismology in seismic hazard assessment, and discusses the direction of its development. The analysis shows that the seismic hazard assessment based on modern earthquake catalogues in most regions should be effective. Particularly, the application of seismic hazard assessment based on ETAS(epidemic type aftershock sequence)should be the easiest and most effective method for the compilation of seismic hazard maps in large urban agglomeration areas and low seismic hazard areas with thick sedimentary zones.
基金supported by the Ministry of Education,Science,Sports and Culture, Grant-in-Aid for Young Scientists(B) 19740265,2007(P.I.for Dr. Yoshiaki Ishihara)
文摘Characteristic infrasound waves observed at Antarctic stations demonstrate physical interaction involving environmental changes in the Antarctic continent and the surrounding oceans. A Chaparraltype infrasound sensor was installed at Syowa Station （SYO; 39°E, 69°S）, East Antarctica, as one of the projects of the International Polar Year （IPY2007-2008）. Data continuously recorded during the three seasons in 2008-2010 clearly indicate a contamination of the background oceanic signals （microbaroms） with peaks between 4 and 10 s observed during a whole season. The peak amplitudes of the microbaroms have relatively lower values during austral winters, caused by a larger amount of sea-ice extending around the Lutzow-Holm Bay near SYO, with decreasing ocean wave loading effects. Micro- baroms measurements are useful tool for characterizing ocean wave climate, complementing other oceanographic and geophysical data. A continuous monitoring by infrasound sensors in the Antarctic firmly contributes to the Comprehensive Nuclear-Test-Ban Treaty （CTBT） in the southern high latitude, together with the Pan-Antarctic Observations System （PAntOS） under the Scientific Committee on Antarctic Research （SCAR）. Detailed measurements of the infrasound waves in Antarctica, consequently, could be a new proxy for monitoring regional environmental change as well as the temporal climate variations in the polar regions.
文摘Infrasound signals in Antarctica reflect physical interaction in the surface environments around the recorded area. In December 2015, an infrasound array by three sensors in the detectable frequency range of 0.1 - 200 Hz, combined with one broadband barometer was deployed at Jang Bogo Station, Terra Nova Bay, Antarctica. The two years of data by the broadband barometer contain characteristic signals that caused by surface environment nearby the station, mixing with local noises such as katabatic winds. Clear continuous signals by oceanic swells (microbaroms) were recorded with a predominant frequency of around 0.2 s. Variations of frequency context and amplitudes in the Power Spectral Density were considered as affected by sea-ice dynamics surrounding the Terra Nova Bay. Monitoring of microbaroms could contribute to understanding ocean wave climate, with other oceanographic, cryospheric and geophysical data in Antarctica. Infrasound data in Terra Nova Bay might be a new proxy for estimating environmental variations affected by global warming, cryosphere dynamics, together with volcanic eruptions in Victoria Land.
基金This work was supported in part by the“Materials Research by Information Integration”Initiative(MI2I)project of the Support Program for Starting Up Innovation Hub from Japan Science and Technology Agency(JST)and a Grant-in-Aid for Scientific Research(B)15H02672 from the Japan Society for the Promotion of Science(JSPS)S.W.gratefully acknowledges financial support from JSPS KAKENHI Grant Number JP18K18017+3 种基金K.H.gratefully acknowledges financial support from JSPS KAKENHI Grant Number JP17K17762a Grant-in-Aid for Scientific Research on Innovative Areas(16H06439)and PRESTO(JPMJPR16NA)C.S.gratefully acknowledges financial support from the Ministry of Education and Science of the Russian Federation(Grant 14.Y26.31.0019)J.M.acknowledges partial financial support by JSPS KAKENHI Grant Number JP16K06768.
文摘The use of machine learning in computational molecular design has great potential to accelerate the discovery of innovative materials.However,its practical benefits still remain unproven in real-world applications,particularly in polymer science.We demonstrate the successful discovery of new polymers with high thermal conductivity,inspired by machine-learning-assisted polymer chemistry.This discovery was made by the interplay between machine intelligence trained on a substantially limited amount of polymeric properties data,expertise from laboratory synthesis and advanced technologies for thermophysical property measurements.Using a molecular design algorithm trained to recognize quantitative structure—property relationships with respect to thermal conductivity and other targeted polymeric properties,we identified thousands of promising hypothetical polymers.From these candidates,three were selected for monomer synthesis and polymerization because of their synthetic accessibility and their potential for ease of processing in further applications.The synthesized polymers reached thermal conductivities of 0.18–0.41 W/mK,which are comparable to those of state-of-the-art polymers in non-composite thermo-plastics.
基金The authors acknowledge financial support from the National Key Research and Development Program of China(No.2016YFB0700500)the National Science Foundation of China(No.51574027,No.61572075,No.6170203,No.61873299)+1 种基金the Finance science and technology project of Hainan province(No.ZDYF2019009)the Fundamental Research Funds for the University of Science and Technology Beijing(No.FRF-BD-19-012A,No.FRF-TP-19-043A2).
文摘Recent progress in material data mining has been driven by high-capacity models trained on large datasets.However,collecting experimental data(real data)has been extremely costly owing to the amount of human effort and expertise required.Here,we develop a novel transfer learning strategy to address problems of small or insufficient data.This strategy realizes the fusion of real and simulated data and the augmentation of training data in a data mining procedure.For a specific task of grain instance image segmentation,this strategy aims to generate synthetic data by fusing the images obtained from simulating the physical mechanism of grain formation and the“image style”information in real images.The results show that the model trained with the acquired synthetic data and only 35%of the real data can already achieve competitive segmentation performance of a model trained on all of the real data.Because the time required to perform grain simulation and to generate synthetic data are almost negligible as compared to the effort for obtaining real data,our proposed strategy is able to exploit the strong prediction power of deep learning without significantly increasing the experimental burden of training data preparation.
基金The numerical calculations were conducted on the five supercomputer systems,Fugaku at the RIKEN Center for Computational Science,Kobe,Japanthe supercomputer at the Research Center for Computational Science,Okazaki,Japan(Project:21-IMS-C126,22-IMS-C125)+7 种基金the supercomputer Ohtaka at the Supercomputer Center,the Institute for Solid State Physics,the University of Tokyo,Tokyo,Japanthe supercomputer TSUBAME3.0 at the Tokyo Institute of Technology,Tokyo,Japanthe supercomputer ABCI at the National Institute of Advanced Industrial Science and Technology,Tsukuba,JapanThis work was supported by the following five grants:a JST CREST(Grant Number JPMJCR19I3 to J.M.and R.Y.)the MEXT as“Program for Promoting Researches on the Supercomputer Fugaku”(Project ID:hp210264 to R.Y.)the Grant-in-Aid for Scientific Research(A)from the Japan Society for the Promotion of Science(19H01132 to R.Y.)the Grant-in-Aid for Scientific Research(C)from the Japan Society for the Promotion of Science(22K11949 to Y.H.)the HPCI System Research Project(Project ID:hp210213 to Y.H.).
文摘The spread of data-driven materials research has increased the need for systematically designed materials property databases.However,the development of polymer databases has lagged far behind other material systems.We present RadonPy,an open-source library that can automate the complete process of all-atom classical molecular dynamics(MD)simulations applicable to a wide variety of polymeric materials.Herein,15 different properties were calculated for more than 1000 amorphous polymers.The MD-calculated properties were systematically compared with experimental data to validate the calculation conditions;the bias and variance in the MD-calculated properties were successfully calibrated by a machine learning technique.During the high-throughput data production,we identified eight amorphous polymers with extremely high thermal conductivity(>0.4 W∙m^(–1)∙K^(–1))and their underlying mechanisms.Similar to the advancement of materials informatics since the advent of computational property databases for inorganic crystals,database construction using RadonPy will promote the development of polymer informatics.
基金This work was supported by JST-Mirai Program Grant Numbers JPMJMI19G1 and JPMJMI21G2T.U.acknowledges the support of JSPS KAKENHI Grant Number JP18K13984 and QST President’s Strategic Grant(Exploratory Research).H.H.acknowledges the support of NEDO Grant Number JPNP18002 and JST CREST Grant Number JPMJCR1761+2 种基金This work was carried out under the ISM Cooperative Research Program(H30-J-4302 and 2019-ISMCRP-4206)The XAS experiment was performed under the approval of the Photon Factory Program Advisory Committee(Proposal No.2018MP001)The authors thank Dr.Yasuo Takeichi for the support of the experiments at the Photon Factory.
文摘The automated stopping of a spectral measurement with active learning is proposed.The optimal stopping of the measurement is realised with a stopping criterion based on the upper bound of the posterior average of the generalisation error of the Gaussian process regression.It is revealed that the automated stopping criterion of the spectral measurement gives an approximated X-ray absorption spectrum with sufficient accuracy and reduced data size.The proposed method is not only a proof-of-concept of the optimal stopping problem in active learning but also the key to enhancing the efficiency of spectral measurements for highthroughput experiments in the era of materials informatics.
