Sample records for joho kiban seibi
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The Future of Political Communication Research: A Japanese Perspective.
ERIC Educational Resources Information Center
Youichi, Ito
1993-01-01
Introduces two Japanese models of mass media effects: (1) the "joho kohdo" (information behavior) model which suggests that people use extracted information to check the credibility of mass media information; and (2) the tripolar "kuuki" model which suggests that the mass media have effects as part of the triadic relationship…
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Development of Automated Moment Tensor Software at the Prototype International Data Center
2000-09-01
Berkeley Digital Seismic Network stations in the 100 to 500 km distance range. With sufficient azimuthal coverage this method is found to perform...the solution reported by NIED (http://argent.geo.bosai.go.jp/ freesia /event/hypo/joho.html). The normal mechanism obtained by the three-component...Digital Seismic Network stations. These stations provide more than 100 degrees of azimuthal coverage, which is an adequate sampling of the focal
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Hao, Yu-Jin; You, Chun-Xiang; Deng, Xui-Xin
2002-01-01
Shoot-tips of 10 strawberry genotypes were successfully cryopreserved using a modified encapsulation-dehydration method. All genotypes survived cryopreservation with high survival and regeneration rates. Eight Joho single-bud sibling lines were established as a model system for genetic analysis. Although cytological examination found chromosomal variation in both non-cryopreserved and cryopreserved samples, the ploidy constitution remained relatively stable after cryopreservation. DNA samples digested with MseI and PstI were used for amplified fragmentation length polymorphism (AFLP) assay. In 16 primer combinations, only one, namely, PCCA-MCAG, detected one site where band pattern changed after cryopreservation, which might be contributed to the change in DNA methylation status at PstI recognition site. Methylation sensitive amplified polymorphism (MSAP) assay was carried out for further investigation on the influence of cryopreservation on DNA methylation status. It was found that cryopreservation induced a significant change in DNA methylation status.
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Application of τc*Pd for identifying damaging earthquakes for earthquake early warning
NASA Astrophysics Data System (ADS)
Huang, P. L.; Lin, T. L.; Wu, Y. M.
2014-12-01
Earthquake Early Warning System (EEWS) is an effective approach to mitigate earthquake damage. In this study, we used the seismic record by the Kiban Kyoshin network (KiK-net), because it has dense station coverage and co-located borehole strong-motion seismometers along with the free-surface strong-motion seismometers. We used inland earthquakes with moment magnitude (Mw) from 5.0 to 7.3 between 1998 and 2012. We choose 135 events and 10950 strong ground accelerograms recorded by the 696 strong ground accelerographs. Both the free-surface and the borehole data are used to calculate τc and Pd, respectively. The results show that τc*Pd has a good correlation with PGV and is a robust parameter for assessing the potential of damaging earthquake. We propose the value of τc*Pd determined from seconds after the arrival of P wave could be a threshold for the on-site type of EEW.
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Impediments to predicting site response: Seismic property estimation and modeling simplifications
Thompson, E.M.; Baise, L.G.; Kayen, R.E.; Guzina, B.B.
2009-01-01
We compare estimates of the empirical transfer function (ETF) to the plane SH-wave theoretical transfer function (TTF) within a laterally constant medium for invasive and noninvasive estimates of the seismic shear-wave slownesses at 13 Kiban-Kyoshin network stations throughout Japan. The difference between the ETF and either of the TTFs is substantially larger than the difference between the two TTFs computed from different estimates of the seismic properties. We show that the plane SH-wave TTF through a laterally homogeneous medium at vertical incidence inadequately models observed amplifications at most sites for both slowness estimates, obtained via downhole measurements and the spectral analysis of surface waves. Strategies to improve the predictions can be separated into two broad categories: improving the measurement of soil properties and improving the theory that maps the 1D soil profile onto spectral amplification. Using an example site where the 1D plane SH-wave formulation poorly predicts the ETF, we find a more satisfactory fit to the ETF by modeling the full wavefield and incorporating spatially correlated variability of the seismic properties. We conclude that our ability to model the observed site response transfer function is limited largely by the assumptions of the theoretical formulation rather than the uncertainty of the soil property estimates.
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Magnitude Estimation for Large Earthquakes from Borehole Recordings
NASA Astrophysics Data System (ADS)
Eshaghi, A.; Tiampo, K. F.; Ghofrani, H.; Atkinson, G.
2012-12-01
We present a simple and fast method for magnitude determination technique for earthquake and tsunami early warning systems based on strong ground motion prediction equations (GMPEs) in Japan. This method incorporates borehole strong motion records provided by the Kiban Kyoshin network (KiK-net) stations. We analyzed strong ground motion data from large magnitude earthquakes (5.0 ≤ M ≤ 8.1) with focal depths < 50 km and epicentral distances of up to 400 km from 1996 to 2010. Using both peak ground acceleration (PGA) and peak ground velocity (PGV) we derived GMPEs in Japan. These GMPEs are used as the basis for regional magnitude determination. Predicted magnitudes from PGA values (Mpga) and predicted magnitudes from PGV values (Mpgv) were defined. Mpga and Mpgv strongly correlate with the moment magnitude of the event, provided sufficient records for each event are available. The results show that Mpgv has a smaller standard deviation in comparison to Mpga when compared with the estimated magnitudes and provides a more accurate early assessment of earthquake magnitude. We test this new method to estimate the magnitude of the 2011 Tohoku earthquake and we present the results of this estimation. PGA and PGV from borehole recordings allow us to estimate the magnitude of this event 156 s and 105 s after the earthquake onset, respectively. We demonstrate that the incorporation of borehole strong ground-motion records immediately available after the occurrence of large earthquakes significantly increases the accuracy of earthquake magnitude estimation and the associated improvement in earthquake and tsunami early warning systems performance. Moment magnitude versus predicted magnitude (Mpga and Mpgv).
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Ishak, Intan H.; Kamgang, Basile; Ibrahim, Sulaiman S.; Riveron, Jacob M.; Irving, Helen
2017-01-01
Background Dengue control and prevention rely heavily on insecticide-based interventions. However, insecticide resistance in the dengue vector Aedes aegypti, threatens the continued effectiveness of these tools. The molecular basis of the resistance remains uncharacterised in many endemic countries including Malaysia, preventing the design of evidence-based resistance management. Here, we investigated the underlying molecular basis of multiple insecticide resistance in Ae. aegypti populations across Malaysia detecting the major genes driving the metabolic resistance. Methodology/Principal Findings Genome-wide microarray-based transcription analysis was carried out to detect the genes associated with metabolic resistance in these populations. Comparisons of the susceptible New Orleans strain to three non-exposed multiple insecticide resistant field strains; Penang, Kuala Lumpur and Kota Bharu detected 2605, 1480 and 425 differentially expressed transcripts respectively (fold-change>2 and p-value ≤ 0.05). 204 genes were commonly over-expressed with monooxygenase P450 genes (CYP9J27, CYP6CB1, CYP9J26 and CYP9M4) consistently the most up-regulated detoxification genes in all populations, indicating that they possibly play an important role in the resistance. In addition, glutathione S-transferases, carboxylesterases and other gene families commonly associated with insecticide resistance were also over-expressed. Gene Ontology (GO) enrichment analysis indicated an over-representation of GO terms linked to resistance such as monooxygenases, carboxylesterases, glutathione S-transferases and heme-binding. Polymorphism analysis of CYP9J27 sequences revealed a high level of polymorphism (except in Joho Bharu), suggesting a limited directional selection on this gene. In silico analysis of CYP9J27 activity through modelling and docking simulations suggested that this gene is involved in the multiple resistance in Malaysian populations as it is predicted to metabolise
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Ishak, Intan H; Kamgang, Basile; Ibrahim, Sulaiman S; Riveron, Jacob M; Irving, Helen; Wondji, Charles S
2017-01-01
Dengue control and prevention rely heavily on insecticide-based interventions. However, insecticide resistance in the dengue vector Aedes aegypti, threatens the continued effectiveness of these tools. The molecular basis of the resistance remains uncharacterised in many endemic countries including Malaysia, preventing the design of evidence-based resistance management. Here, we investigated the underlying molecular basis of multiple insecticide resistance in Ae. aegypti populations across Malaysia detecting the major genes driving the metabolic resistance. Genome-wide microarray-based transcription analysis was carried out to detect the genes associated with metabolic resistance in these populations. Comparisons of the susceptible New Orleans strain to three non-exposed multiple insecticide resistant field strains; Penang, Kuala Lumpur and Kota Bharu detected 2605, 1480 and 425 differentially expressed transcripts respectively (fold-change>2 and p-value ≤ 0.05). 204 genes were commonly over-expressed with monooxygenase P450 genes (CYP9J27, CYP6CB1, CYP9J26 and CYP9M4) consistently the most up-regulated detoxification genes in all populations, indicating that they possibly play an important role in the resistance. In addition, glutathione S-transferases, carboxylesterases and other gene families commonly associated with insecticide resistance were also over-expressed. Gene Ontology (GO) enrichment analysis indicated an over-representation of GO terms linked to resistance such as monooxygenases, carboxylesterases, glutathione S-transferases and heme-binding. Polymorphism analysis of CYP9J27 sequences revealed a high level of polymorphism (except in Joho Bharu), suggesting a limited directional selection on this gene. In silico analysis of CYP9J27 activity through modelling and docking simulations suggested that this gene is involved in the multiple resistance in Malaysian populations as it is predicted to metabolise pyrethroids, DDT and bendiocarb. The predominant
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NASA Astrophysics Data System (ADS)
Herman, M. W.; Furlong, K. P.; Hayes, G. P.; Benz, H.
2014-12-01
Strong motion accelerometers can record large amplitude shaking on-scale in the near-field of large earthquake ruptures; however, numerical integration of such records to determine displacement is typically unstable due to baseline changes (i.e., distortions in the zero value) that occur during strong shaking. We use datasets from the 2011 Mw 9.0 Tohoku earthquake to assess whether a relatively simple empirical correction scheme (Boore et al., 2002) can return accurate displacement waveforms useful for constraining details of the fault slip. The coseismic deformation resulting from the Tohoku earthquake was recorded by the Kiban Kyoshin network (KiK-net) of strong motion instruments as well as by a dense network of high-rate (1 Hz) GPS instruments. After baseline correcting the KiK-net records and integrating to displacement, over 85% of the KiK-net borehole instrument waveforms and over 75% of the KiK-net surface instrument waveforms match collocated 1 Hz GPS displacement time series. Most of the records that do not match the GPS-derived displacements following the baseline correction have large, systematic drifts that can be automatically identified by examining the slopes in the first 5-10 seconds of the velocity time series. We apply the same scheme to strong motion records from the 2014 Mw 8.2 Iquique earthquake. Close correspondence in both direction and amplitude between coseismic static offsets derived from the integrated strong motion time series and those predicted from a teleseismically-derived finite fault model, as well as displacement amplitudes consistent with InSAR-derived results, suggest that the correction scheme works successfully for the Iquique event. In the absence of GPS displacements, these strong motion-derived offsets provide constraints on the overall distribution of slip on the fault. In addition, the coseismic strong motion-derived displacement time series (50-100 s long) contain a near-field record of the temporal evolution of the
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NASA Astrophysics Data System (ADS)
Fukuyama, E.; Dreger, D. S.
2000-06-01
We have investigated how the automated moment tensor determination (AMTD) system using the FREESIA/KIBAN broadband network is likely to behave during a future large earthquake. Because we do not have enough experience with a large (M >8) nearby earthquake, we computed synthetic waveforms for such an event by assuming the geometrical configuration of the anticipated Tokai earthquake and several fault rupture scenarios. Using this synthetic data set, we examined the behavior of the AMTD system to learn how to prepare for such an event. For our synthetic Tokai event data we assume its focal mechanism, fault dimension, and scalar seismic moment. We also assume a circular rupture propagation with constant rupture velocity and dislocation rise time. Both uniform and heterogeneous slip models are tested. The results show that performance depends on both the hypocentral location (i.e. unilateral vs. bilateral) and the degree of heterogeneity of slip. In the tests that we have performed the rupture directivity appears to be more important than slip heterogeneity. We find that for such large earthquakes it is necessary to use stations at distances greater than 600 km and frequencies between 0.005 to 0.02 Hz to maintain a point-source assumption and to recover the full scalar seismic moment and radiation pattern. In order to confirm the result of the synthetic test, we have analyzed the 1993 Hokkaido Nansei-oki (MJ7.8) and the 1995 Kobe (MJ7.2) earthquakes by using observed broadband waveforms. For the Kobe earthquake we successfully recovered the moment tensor by using the routinely used frequency band (0.01-0.05 Hz displacements). However, we failed to estimate a correct solution for the Hokkaido Nansei-oki earthquake by using the same routine frequency band. In this case, we had to use the frequencies between 0.005 to 0.02 Hz to recover the moment tensor, confirming the validity of the synthetic test result for the Tokai earthquake.
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NASA Astrophysics Data System (ADS)
Hayashida, T.; Tajima, F.
2007-12-01
The Real-time Earthquake Information System (REIS, Horiuchi et al., 2005) detects earthquakes and determines event parameters using the Hi-net (High-sensitivity seismograph network Japan) data in Japan. The system also predicts the arrival time and seismic intensity at a given site before ground motions arrive. Here, the seismic intensity is estimated based on the intensity magnitude which is derived from data of the Hi-net. As the Hi-net stations are located in the boreholes, intensity estimation on the ground surface is evaluated using a constant for subsurface amplification. But the estimated intensities based on the conventionally used amplification constants are not always in agreement with those observed at specific sites on the ground surface. The KiK-net (KIBAN Kyoshin network Japan) consists of strong motion instruments. Each station has two sets of accelerometers, one set is installed on the ground surface and the other one is co-located with a Hi-net station in the borehole. We use data recorded at the KiK-net stations to calibrate subsurface site amplification factors between the borehole and the ground surface. We selected data recorded for over 200 events during the period of 1997 to 2006 in Hiroshima prefecture and calculated the ratios of peak velocity amplitudes on the ground surface ( Asurf) to those in the borehole ( Abor). The subsurface amplification varies from station to station showing dependency on the propagation distance as well as on the incident direction of seismic waves. Results suggest that the site amplification factors shall be described as a function of distance and incident direction, and are not constants. Thus, we derived empirical amplification formulas between Asurf and the peak velocity amplitudes on the engineering bedrock ( Abed) as a function of distance in place of the conventionally used amplification constants. Here, the engineering bedrock is defined as the depth where the S- wave velocity is 600 m/s. The estimated
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Magnitude Estimation for the 2011 Tohoku-Oki Earthquake Based on Ground Motion Prediction Equations
NASA Astrophysics Data System (ADS)
Eshaghi, Attieh; Tiampo, Kristy F.; Ghofrani, Hadi; Atkinson, Gail M.
2015-08-01
This study investigates whether real-time strong ground motion data from seismic stations could have been used to provide an accurate estimate of the magnitude of the 2011 Tohoku-Oki earthquake in Japan. Ultimately, such an estimate could be used as input data for a tsunami forecast and would lead to more robust earthquake and tsunami early warning. We collected the strong motion accelerograms recorded by borehole and free-field (surface) Kiban Kyoshin network stations that registered this mega-thrust earthquake in order to perform an off-line test to estimate the magnitude based on ground motion prediction equations (GMPEs). GMPEs for peak ground acceleration and peak ground velocity (PGV) from a previous study by Eshaghi et al. in the Bulletin of the Seismological Society of America 103. (2013) derived using events with moment magnitude ( M) ≥ 5.0, 1998-2010, were used to estimate the magnitude of this event. We developed new GMPEs using a more complete database (1998-2011), which added only 1 year but approximately twice as much data to the initial catalog (including important large events), to improve the determination of attenuation parameters and magnitude scaling. These new GMPEs were used to estimate the magnitude of the Tohoku-Oki event. The estimates obtained were compared with real time magnitude estimates provided by the existing earthquake early warning system in Japan. Unlike the current operational magnitude estimation methods, our method did not saturate and can provide robust estimates of moment magnitude within ~100 s after earthquake onset for both catalogs. It was found that correcting for average shear-wave velocity in the uppermost 30 m () improved the accuracy of magnitude estimates from surface recordings, particularly for magnitude estimates of PGV (Mpgv). The new GMPEs also were used to estimate the magnitude of all earthquakes in the new catalog with at least 20 records. Results show that the magnitude estimate from PGV values using
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Three-dimensional site response at KiK-net downhole arrays
Thompson, Eric M.; Tanaka, Yasuo; Baise, Laurie G.; Kayen, Robert E.
2010-01-01
Ground motions at two Kiban-Kyoshin Network (KiK-net) strong motion downhole array sites in Hokkaido, Japan (TKCH08 in Taiki and TKCH05 in Honbetsu) illustrate the importance of three-dimensional (3D) site effects. These sites recorded the M8.0 2003 Tokachi-Oki earthquake, with recorded accelerations above 0.4 g at both sites as well as numerous ground motions from smaller events. Weak ground motions indicate that site TKCH08 is well modeled with the assumption of plane SH waves traveling through a 1D medium (SH1D), while TKCH05 is characteristic of a poor fit to the SH1D theoretical response. We hypothesized that the misfit at TKCH05results from the heterogeneity of the subsurface. To test this hypothesis, we measured four S-wave velocity profiles in the vicinity (< 300 m) of each site with the spectral analysis of surface waves (SASW) method. This KiK-net site pair is ideal for assessing the relative importance of 3D site effects and nonlinear site effects. The linear ground motions at TKCH05 isolate the 3D site effects, as we hypothesized from the linear ground motions and confirmed with our subsequent SASW surveys. The Tokachi-Oki time history at TKCH08 isolates the effects of nonlinearity from spatial heterogeneity because the 3D effects are negligible. The Tokachi-Oki time history at TKCH05 includes both nonlinear and 3D site effects. Comparisons of the accuracy of the SH1D model predictions of these surface time histories from the downhole time histories indicates that the 3D site effects are at least as important as nonlinear effects in this case. The errors associated with the assumption of a 1D medium and 1D wave propagation will be carried into a nonlinear analysis that relies on these same assumptions. Thus, the presence of 3D effects should be ruled out prior to a 1D nonlinear analysis. The SH1D residuals show that 3D effects can be mistaken for nonlinear effects.
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NASA Astrophysics Data System (ADS)
Kita, S.; Hasegawa, A.; Nakajima, J.; Okada, T.; Matsuzawa, T.; Katsumata, K.
2011-12-01
Using arrival-time data both from the nationwide Kiban seismic network and from a dense temporary seismic network covering the area of the Hokkaido corner [Katsumata et al., 2002a; 2003, JGR], we precisely determined three-dimensional seismic velocity structure beneath this area to understand the collision process between the Kuril and northeasetern Japan forearcs. Tomographic inversions were performed with smaller grid spacing [5 x 10 x 5 km] than our previous study [Kita et al., 2010b, EPSL] by using the double-difference tomography method [Zhang and Thurber, 2003; 2006]. Inhomogeneous seismic velocity structure was more precisely imaged in the Hokkaido corner at depths of 0-120 km. A broad low-velocity zone of P- and S- waves having velocities of crust materials with a total volume of 80 km x 100 km x 50 km is distributed to the west of the Hidaka metamorphic belt (the Hidaka main thrust) at depths of 30-90km. On the other hand, several small-scale high-velocity zones having velocities of mantle materials were detected at depths of 0-35 km), inclined east-northeastward at a high angle of 40-60 degrees. All of these anomaly high velocity zones are respectively located in the deeper extension of the Neogene thrust faults, striking almost N-S direction and dipping 40-50 degrees at depths of 0-10km [e.g. Ito 2000]. The largest high-velocity zone is located in the deeper extension of the Hidaka main thrust, being in contact with the eastern edge of the low-V zone. This high-V zone reaches near the surface at the Hidaka metamorphic belt and its southern edge is located just beneath the Horoman-peridotite, which is one of the most famous peridotite outcrops. Moreover, the boundary of the high-V zone with the broad low-V zone corresponds to the fault plane of the 1970 Mj 6.7 Hidaka region earthquake [Moriya 1972]. Another high-V zone is located within the broad low-V zone at depths of 20-30km and in the deeper extension of thrust, which belongs to the Ishikari Low land
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NASA Astrophysics Data System (ADS)
Kita, S.; Hasegawa, A.; Okada, T.; Nakajima, J.; Matsuzawa, T.; Katsumata, K.
2010-12-01
1. Introduction In south-eastern Hokkaido, the Kuril forearc sliver is colliding with the northeastern Japan arc due to the oblique subduction of the Pacific plate. This collision causes the formation of the Hidaka mountain range since the late Miocene (Kimura, 1986) and delamination of the lower-crust materials of the Kuril forearc sliver, which would be expected to descend into the mantle wedge below (e.g., Ito 2000; Ito and Iwasaki, 2002). In this study, we precisely investigated the three-dimensional seismic velocity structure beneath the Hokkaido corner to examine the collision of two forearcs in this area by using both of data from a dense temporary seismic network deployed in this area (Katsumata et al. [2006]) and those from the Kiban observation network, which covers the entire Japanese Islands with a station separation of 15-20 km. 2. Data and method The double-difference tomography method (Zhang and Thurber, 2003; 2006) was applied to a large number of arrival time data of 201,527 for P-waves and 150,963 for S-waves that were recorded at 125 stations from 10,971 earthquakes that occurred from 1999 to 2010. Grid intervals were set at 10 km in the along-arc direction, 12.5 km perpendicular to it, and 5-10 km in the vertical direction. 3. Results and discussion Inhomogeneous seismic velocity structure was clearly imaged in the Hokkaido corner at depths of 0-120 km. A high-velocity anomaly of P- and S- waves with a volume of 20 km x 90 km x 35km was detected just beneath the main zone of the Hidaka metamorphic belt at depths of 0-35 km. This high-velocity anomaly is continuously distributed from the depths of the mantle wedge to the surface. The western edge of the anomaly exactly corresponds to the Hidaka main thrust (HMT) at the surface. The highest velocity value in the anomaly corresponds to those of the uppermost mantle material (e.g. peridotite). The location of them at depths of 0-35km is also consistent with that of the Horoman-Peridotite belt, which