The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Masayuki U Saito - One of the best experts on this subject based on the ideXlab platform.
-
symptomatic raccoon dogs and sarcoptic mange along an urban gradient
Ecohealth, 2017Co-Authors: Masayuki U Saito, Yoichi SonodaAbstract:We quantitatively evaluated the effects of landscape factors on the distribution of symptomatic raccoon dogs with sarcoptic mange along an urban gradient. We used 246 camera traps (182 traps from April 2005 to December 2006; 64 traps from September 2009 to October 2010) to record the Occurrence of asymptomatic and symptomatic raccoon dogs at 21 survey sites along an urban–rural gradient in the Tama Hills area of Tokyo. Each Occurrence was explained in terms of the surrounding forest, agricultural, and grassland areas and additional factors (i.e., seasonal variations and survey methods) at various spatial scales using a generalized additive mixed model (GAMM). In our analysis, a 1000-m radius was identified as the important spatial scale for asymptomatic and symptomatic raccoon dog Occurrence. The peak of the predicted Occurrence Probability of asymptomatic raccoon dogs appeared in the intermediate forest landscape as opposed to non-forest and forest landscapes. However, a high Occurrence Probability of symptomatic raccoon dogs was detected in non-forest and intermediate forest landscapes (i.e., urban and suburban) as opposed to a forest landscape, presumably because of animals occurring at much higher densities in more urbanized areas. Therefore, our results suggest that human-modified landscapes play an important role in the high Occurrence of sarcoptic mange in raccoon dogs.
-
symptomatic raccoon dogs and sarcoptic mange along an urban gradient
Ecohealth, 2017Co-Authors: Masayuki U Saito, Yoichi SonodaAbstract:We quantitatively evaluated the effects of landscape factors on the distribution of symptomatic raccoon dogs with sarcoptic mange along an urban gradient. We used 246 camera traps (182 traps from April 2005 to December 2006; 64 traps from September 2009 to October 2010) to record the Occurrence of asymptomatic and symptomatic raccoon dogs at 21 survey sites along an urban–rural gradient in the Tama Hills area of Tokyo. Each Occurrence was explained in terms of the surrounding forest, agricultural, and grassland areas and additional factors (i.e., seasonal variations and survey methods) at various spatial scales using a generalized additive mixed model (GAMM). In our analysis, a 1000-m radius was identified as the important spatial scale for asymptomatic and symptomatic raccoon dog Occurrence. The peak of the predicted Occurrence Probability of asymptomatic raccoon dogs appeared in the intermediate forest landscape as opposed to non-forest and forest landscapes. However, a high Occurrence Probability of symptomatic raccoon dogs was detected in non-forest and intermediate forest landscapes (i.e., urban and suburban) as opposed to a forest landscape, presumably because of animals occurring at much higher densities in more urbanized areas. Therefore, our results suggest that human-modified landscapes play an important role in the high Occurrence of sarcoptic mange in raccoon dogs.
Yoichi Sonoda - One of the best experts on this subject based on the ideXlab platform.
-
symptomatic raccoon dogs and sarcoptic mange along an urban gradient
Ecohealth, 2017Co-Authors: Masayuki U Saito, Yoichi SonodaAbstract:We quantitatively evaluated the effects of landscape factors on the distribution of symptomatic raccoon dogs with sarcoptic mange along an urban gradient. We used 246 camera traps (182 traps from April 2005 to December 2006; 64 traps from September 2009 to October 2010) to record the Occurrence of asymptomatic and symptomatic raccoon dogs at 21 survey sites along an urban–rural gradient in the Tama Hills area of Tokyo. Each Occurrence was explained in terms of the surrounding forest, agricultural, and grassland areas and additional factors (i.e., seasonal variations and survey methods) at various spatial scales using a generalized additive mixed model (GAMM). In our analysis, a 1000-m radius was identified as the important spatial scale for asymptomatic and symptomatic raccoon dog Occurrence. The peak of the predicted Occurrence Probability of asymptomatic raccoon dogs appeared in the intermediate forest landscape as opposed to non-forest and forest landscapes. However, a high Occurrence Probability of symptomatic raccoon dogs was detected in non-forest and intermediate forest landscapes (i.e., urban and suburban) as opposed to a forest landscape, presumably because of animals occurring at much higher densities in more urbanized areas. Therefore, our results suggest that human-modified landscapes play an important role in the high Occurrence of sarcoptic mange in raccoon dogs.
-
symptomatic raccoon dogs and sarcoptic mange along an urban gradient
Ecohealth, 2017Co-Authors: Masayuki U Saito, Yoichi SonodaAbstract:We quantitatively evaluated the effects of landscape factors on the distribution of symptomatic raccoon dogs with sarcoptic mange along an urban gradient. We used 246 camera traps (182 traps from April 2005 to December 2006; 64 traps from September 2009 to October 2010) to record the Occurrence of asymptomatic and symptomatic raccoon dogs at 21 survey sites along an urban–rural gradient in the Tama Hills area of Tokyo. Each Occurrence was explained in terms of the surrounding forest, agricultural, and grassland areas and additional factors (i.e., seasonal variations and survey methods) at various spatial scales using a generalized additive mixed model (GAMM). In our analysis, a 1000-m radius was identified as the important spatial scale for asymptomatic and symptomatic raccoon dog Occurrence. The peak of the predicted Occurrence Probability of asymptomatic raccoon dogs appeared in the intermediate forest landscape as opposed to non-forest and forest landscapes. However, a high Occurrence Probability of symptomatic raccoon dogs was detected in non-forest and intermediate forest landscapes (i.e., urban and suburban) as opposed to a forest landscape, presumably because of animals occurring at much higher densities in more urbanized areas. Therefore, our results suggest that human-modified landscapes play an important role in the high Occurrence of sarcoptic mange in raccoon dogs.
Nobuhito Mori - One of the best experts on this subject based on the ideXlab platform.
-
freak wave in high order weakly nonlinear wave evolution with bottom topography change
Coastal Engineering, 2021Co-Authors: Zuorui Lyu, Nobuhito Mori, Hiroaki KashimaAbstract:Abstract In deep-water, quasi-resonant four-wave interaction gives rise to the Occurrence Probability of extreme wave height, which leads to freak wave as a natural disaster. As water wave enters shallow water, four-wave interaction becomes weak and wave shoaling makes this effect become complicated. This study conducts a Monte Carlo simulation in modified Nonlinear Schrodinger equation considering bottom topography change, and gives spatial evolution of high-order nonlinearity in wave train from statistical moment. The result indicates, slope angle plays an important role in a shallow water depth, and steep slope brings about a significant enhancement of extreme event in distribution of maximum wave height and surface elevation.
-
estimation of maximum wave height of observation data and its application to freak wave prediction
Journal of Japan Society of Civil Engineers, 2011Co-Authors: Nobuhito Mori, Takeru Michimae, Hiroaki Shimada, Hajime MaseAbstract:A linear envelope assumption and quasi-resonant four-wave interactions for deep-water random waves may influence the statistical properties of deep-water surface gravity waves. As a consequence, the exceedance Probability of wave height substantially deviates from the expected distribution obtained by assuming linear narrow banded spectrum waves. Here the Occurrence Probability of maximum wave heights is compared with ocean wave measurements during the yearsd 2001-2005 around Japan. The maximum wave height distribution and Probability of Occurrence of freak waves are compared with theoretical expectations and are adjusted by the measured data. The proposed distribution well predicts extreme waves in nonlinear random wave fields.
-
on kurtosis and Occurrence Probability of freak waves
Journal of Physical Oceanography, 2006Co-Authors: Nobuhito Mori, Peter A. E. M. JanssenAbstract:Based on a weakly non-Gaussian theory, the Occurrence Probability of freak waves is formulated in terms of the number of waves in a time series and the surface elevation kurtosis. Finite kurtosis gives rise to a significant enhancement of freak wave generation in comparison with the linear narrowbanded wave theory. For a fixed number of waves, the estimated amplification ratio of freak wave Occurrence due to the deviation from the Gaussian theory is 50%–300%. The results of the theory are compared with laboratory and field data.
-
Occurrence Probability of a freak wave in a nonlinear wave field
Ocean Engineering, 2004Co-Authors: Nobuhito MoriAbstract:Abstract The Edgeworth’s form of a cumulative expansion of the Probability density function (PDF) of surface elevation expands the maximum wave height distribution to predict the Occurrence Probability of freak waves. This study investigated the enhancement of the Occurrence Probability of freak waves due to the fourth order moment of surface elevation, kurtosis, change and found that the nonlinear effects on the Occurrence Probability of a freak wave linearly depends on kurtosis for a small number of waves N =250. The statistical theory was compared with field data, and freak waves sometimes appear when not expected by the Rayleigh theory, but they were predicted by the proposed theory.
-
dependence of freak wave Occurrence on kurtosis
Actes de colloques - IFREMER, 2004Co-Authors: Nobuhito Mori, Peter A. E. M. JanssenAbstract:The Occurrence Probability of freak waves is formulated as a function of number of waves and surface elevation kurtosis based on the weakly non-Gaussian theory. Finite kurtosis gives rise to a significant enhancement of freak wave generation. For fixed number of waves, the estimated amplification ratio of freak wave Occurrence due to the deviation from the Gaussian theory is 50%-300%.
F S Mozer - One of the best experts on this subject based on the ideXlab platform.
-
statistical study of whistler waves in the solar wind at 1 au
The Astrophysical Journal, 2019Co-Authors: Yuguang Tong, I Y Vasko, A V Artemyev, S D Bale, F S MozerAbstract:Whistler waves are intermittently present in the solar wind, while their origin and effects are not entirely understood. We present a statistical analysis of magnetic field fluctuations in the whistler frequency range (above 16 Hz) based on about 801,500 magnetic field spectra measured over three years aboard ARTEMIS spacecraft in the pristine solar wind. About 13,700 spectra (30 hours in total) with intense magnetic field fluctuations satisfy the interpretation in terms of quasi-parallel whistler waves. We provide estimates of the whistler wave Occurrence Probability, amplitudes, frequencies and bandwidths. The Occurrence Probability of whistler waves is shown to strongly depend on the electron temperature anisotropy. The whistler waves amplitudes are in the range from about 0.01 to 0.1 nT and typically below 0.02 of the background magnetic field. The frequencies of the whistler waves are shown to be below an upper bound that is dependent on $\beta_{e}$. The correlations established between the whistler wave properties and local macroscopic plasma parameters suggest that the observed whistler waves can be generated in local plasmas by the whistler heat flux instability. The whistler wave amplitudes are typically small, which questions the hypothesis that quasi-parallel whistler waves are capable to regulate the electron heat flux in the solar wind. We show that the observed whistler waves have sufficiently wide bandwidths and small amplitudes, so that effects of the whistler waves on electrons can be addressed in the frame of the quasi-linear theory.
A V Artemyev - One of the best experts on this subject based on the ideXlab platform.
-
statistical study of whistler waves in the solar wind at 1 au
The Astrophysical Journal, 2019Co-Authors: Yuguang Tong, I Y Vasko, A V Artemyev, S D Bale, F S MozerAbstract:Whistler waves are intermittently present in the solar wind, while their origin and effects are not entirely understood. We present a statistical analysis of magnetic field fluctuations in the whistler frequency range (above 16 Hz) based on about 801,500 magnetic field spectra measured over three years aboard ARTEMIS spacecraft in the pristine solar wind. About 13,700 spectra (30 hours in total) with intense magnetic field fluctuations satisfy the interpretation in terms of quasi-parallel whistler waves. We provide estimates of the whistler wave Occurrence Probability, amplitudes, frequencies and bandwidths. The Occurrence Probability of whistler waves is shown to strongly depend on the electron temperature anisotropy. The whistler waves amplitudes are in the range from about 0.01 to 0.1 nT and typically below 0.02 of the background magnetic field. The frequencies of the whistler waves are shown to be below an upper bound that is dependent on $\beta_{e}$. The correlations established between the whistler wave properties and local macroscopic plasma parameters suggest that the observed whistler waves can be generated in local plasmas by the whistler heat flux instability. The whistler wave amplitudes are typically small, which questions the hypothesis that quasi-parallel whistler waves are capable to regulate the electron heat flux in the solar wind. We show that the observed whistler waves have sufficiently wide bandwidths and small amplitudes, so that effects of the whistler waves on electrons can be addressed in the frame of the quasi-linear theory.