Underestimation of Microearthquake Size by the Magnitude Scale of the Japan Meteorological Agency: Influence on Earthquake Statistics

2018 ◽  
Vol 123 (1) ◽  
pp. 606-620 ◽  
Author(s):  
Takahiko Uchide ◽  
Kazutoshi Imanishi
Keyword(s):  
Japan Meteorological Agency ◽  
Magnitude Scale ◽  
Earthquake Statistics

Magnitude-frequency relations for northeastern Japan

1993 ◽  
Vol 83 (5) ◽  
pp. 1492-1506
Author(s):  
Norihito Umino ◽  
I. Selwyn Sacks
Keyword(s):  
Seismic Wave ◽  
Seismic Network ◽  
Japan Meteorological Agency ◽  
Magnitude Scale ◽  
Benioff Zone ◽  
Earthquake Occurrence ◽  
Land Area ◽  
Velocity Amplitude ◽  
Wave Duration ◽  
Northeastern Japan

Abstract Magnitude-frequency relations are investigated for the on-land area, covered by the Tohoku University seismic network, northeastern Japan. We combine the Japan Meteorological Agency (JMA) catalog with the Tohoku University catalog for the crustal events. The suite for the upper plane events of the double-planed Wadati-Benioff zone, from 60 km through 100 km deep, is based on the Tohoku University catalog only. Completeness analyses of the catalog reveal that the crustal events and the upper plane events suite is complete down to magnitude 2.0 and 2.1, respectively. Including events only with magnitude above the completeness threshold, the magnitude-frequency relations are found to be nonlinear both for the crustal events slightly and the upper plane events strongly. Consistency between total seismic wave duration magnitudes and velocity amplitude magnitudes suggests that the magnitude scale in the catalog is nonbiased. The completeness analyses and the non-biased magnitude scale suggest that the nonlinear magnitude-frequency relations are not artificial but substantial features of the earthquake occurrence.

The Effect of Odor and Color on Chemical Cooling

2019 ◽  
Author(s):  
Robert Pellegrino ◽  
Curtis Luckett
Keyword(s):  
Primary Component ◽  
Magnitude Scale ◽  
Trigeminal System ◽  
Abstract Concepts ◽  
Specific Chemical ◽  
Chemical Binding ◽  
Cooling Intensity ◽  
Crossmodal Associations ◽  
First Session

Chemesthesis, along with taste and olfaction, is a primary component of flavor that engages the trigeminal system through specific chemical binding. For instance, many gums or confectionaries incorporate chemical cooling agents, such as Wilkinson Sword (WS) compounds, to create the sensation of coldness. The current study was designed to evaluate crossmodal associations of color and aroma with the chemesthetic perception of cooling. A “minty” and non-odorized set of confectionary stimuli, colored green, blue or white, with moderate cooling properties (with WS-3) were used in this study. In the first session, participants were randomly presented a stimuli and asked to rate several attributes including its cooling intensity on a generalized Labeled Magnitude Scale (gLMS). In the second session, the same participants were asked to relate cooling levels to different colors and which color relates to the “minty” odor. Additionally, open-ended reasons were given for association choices. Appearance and odor influenced the intensity of cooling sensation. In particular, the odorized and blue samples were rated as cooler than the non-odorized and other colored samples, respectively. The follow-up session confirms blue as a color associated with cooling properties, especially cool objects/abstract concepts. Meanwhile, odor’s enhancement on cooling sensation may be more perceptual in nature through affective matching from enhanced flavor.

scholarly journals Comparison of length and dynamics of wood pieces in streams covered with coniferous and broadleaf forests mapped using orthophotos acquired by an unmanned aerial vehicle

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Haruka Tsunetaka ◽  
Slim Mtibaa ◽  
Shiho Asano ◽  
Takashi Okamoto ◽  
Ushio Kurokawa
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Debris Flows ◽  
Rain Gauge ◽  
Japan Meteorological Agency ◽  
Landslide Occurrence ◽  
Direct Measurements ◽  
Wood Piece ◽  
Aerial Vehicle ◽  
Main Components ◽  
Landslides And Debris Flows

AbstractAs wood pieces supplied by landslides and debris flows are one of the main components of ecological and geomorphic systems, the importance of quantifying the dimensions of the wood pieces is evident. However, the low accessibility of disturbed channels after debris flows generally impedes accurate and quick wood-piece investigations. Thus, remote-sensing measurements for wood pieces are necessitated. Focusing on sub-watersheds in coniferous and broadleaf forests in Japan (the CF and BF sites, respectively), we measured the lengths of wood pieces supplied by landslides (> 0.2 m length and > 0.03 m diameter) from orthophotos acquired using a small unmanned aerial vehicle (UAV). The measurement accuracy was analyzed by comparing the lengths derived from the UAV method with direct measurements. The landslides at the CF and BF sites were triggered by extremely heavy rainfalls in 2017 and 2018, respectively. UAV flights were operated during February and September 2019 at the CF site and during November 2018 and December 2019 at the BF site. Direct measurements of wood pieces were carried out on the date of the respective second flight date in each site. When both ends of a wood piece are satisfactorily extracted from an orthophoto acquired by the UAV, the wood-piece lengths at the CF site can be measured with an accuracy of approximately ±0.5 m. At the BF site, most of the extracted lengths were shorter than the directly measured lengths, probably because the complex structures of the root wad and tree crown reduced the visibility. Most wood pieces were discharged from landslide scars at the BF site, but at the CF site, approximately 750 wood pieces remained in the landslide scars approximately 19 months after the landslide occurrence. The number of wood pieces in the landslide scars of the CF site increased with increasing landslide area, suggesting that some wood pieces can be left even if large landslides occur. The lengths and locations of the entrapped wood pieces at both sites were not significantly changed between the two UAV flight dates. However, during this period, the rainfall intensities around the CF site measured by the closest rain-gauge of the Japan Meteorological Agency reached their second highest values from 1976 to 2019, which exceeded the 30-year return period. This suggests that most of the entrapped wood pieces rarely migrated even under intense rainfall.

Development and testing of a labeled magnitude scale of perceived satiety

Appetite ◽  
2005 ◽  
Vol 44 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Armand V. Cardello ◽  
Howard G. Schutz ◽  
Larry L. Lesher ◽  
Ellen Merrill
Keyword(s):  
Magnitude Scale

Apparent magnitude scale: incandescent lamps

2018 ◽  
Vol 53 (5) ◽  
pp. 055005 ◽  
Author(s):  
Dulli Chandra Agrawal
Keyword(s):  
Magnitude Scale ◽  
Apparent Magnitude ◽  
Incandescent Lamps

A magnitude scale for local earthquakes in South Australia

1975 ◽  
Vol 65 (5) ◽  
pp. 1267-1285
Author(s):  
Ian C. F. Stewart
Keyword(s):  
Epicentral Distance ◽  
South Australia ◽  
Magnitude Scale ◽  
Source Spectrum ◽  
S Waves ◽  
Scale Parameters ◽  
Local Earthquakes ◽  
Dependent Absorption ◽  
Relationship Of ◽  
The Relationship

Abstract To minimize dispersion in local magnitude estimates due to different instrumental bandwidths, a scale has been established to allow for the average source spectrum, geometrical attenuation, and frequency-dependent absorption. The data used to derive the scale parameters were from S waves recorded in South Australia from 1967 through 1970, in the frequency range 1 to 10 Hz, and for epicentral distances up to 5°. The magnitudes were mainly in the range 1.5 to 3.5. The local scale MN is given by M N = 4.85 + log A g + 0.84 log Δ + 0.0003 f Δ / 2.3 − 2.89 log f + 2.45 ( log f ) 2 + c where Ag mm is the ground amplitude at f Hz at Δ km epicentral distance, and c is a station correction. The dispersion in observations of magnitude has probably been reduced by use of the scale to near the theoretical limits, allowing for possible source radiation patterns. The relationship of the scale to other measures of magnitude is uncertain, but MN may be approximately equivalent to the local Richter magnitude ML for the magnitude range (1.5 < ML < 3.5) commonly observed in South Australia. The scle is limited in use to data in the ranges given above, for local earthquakes in South Australia. Modification is necessary before such a magnitude scale can be applied elsewhere or to different data ranges.

The Extended Integrated Particle Filter Method (IPFx) as a High-Performance Earthquake Early Warning System

2021 ◽  
Author(s):  
Masumi Yamada ◽  
Koji Tamaribuchi ◽  
Stephen Wu
Keyword(s):  
Particle Filter ◽  
Early Warning ◽  
Seismic Intensity ◽  
Earthquake Early Warning ◽  
Japan Meteorological Agency ◽  
Estimation Accuracy ◽  
Filter Method ◽  
Source Estimation ◽  
Single Station ◽  
Seismic Networks

ABSTRACT An earthquake early warning (EEW) system rapidly analyzes seismic data to report the occurrence of an earthquake before strong shaking is felt at a site. In Japan, the integrated particle filter (IPF) method, a new source-estimation algorithm, was recently incorporated into the EEW system to improve the source-estimation accuracy during active seismicity. The problem of the current IPF method is that it uses the trigger information computed at each station in a specific format as the input and is therefore applicable to only limited seismic networks. This study proposes the extended IPF (IPFx) method to deal with continuous waveforms and merge all Japanese real-time seismic networks into a single framework. The new source determination algorithm processes seismic waveforms in two stages. The first stage (single-station processing) extracts trigger and amplitude information from continuous waveforms. The second stage (network processing) accumulates information from multiple stations and estimates the location and magnitude of ongoing earthquakes based on Bayesian inference. In 10 months of continuous online experiments, the IPFx method showed good performance in detecting earthquakes with maximum seismic intensity ≥3 in the Japan Meteorological Agency (JMA) catalog. By merging multiple seismic networks into a single EEW system, the warning time of the current EEW system can be improved further. The IPFx method provides accurate shaking estimation even at the beginning of event detection and achieves seismic intensity error <0.25  s after detecting an event. This method correctly avoided two major false alarms on 5 January 2018 and 30 July 2020. The IPFx method offers the potential of expanding the JMA IPF method to global seismic networks.

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