Mixed Zero-Inflation Method and Probability Distribution in Fitting Daily Rainfall Data

In hydrological processes, rainfall is one of the important components of water supply for human life. We considered how well the statistical distribution simulates rainfall intensity. We propose an asymmetric statistical probability distribution joined by zero-inflated to fit the daily continuous record of rainfall data in Thailand. The candidate statistical probabilities are General Pareto, Exponential, Beta, Gamma, Generalize extreme value, Extreme Value, Normal, Lognormal, Weibull and Rayleigh distribution. The daily data from 123 rain gauges in Thailand collected and removed in a given year, using the null value. The statistical distributions estimated on the statistical coefficient, using the maximum likelihood estimation (MLE) method and resulted in a cumulative density function (CDF). The CDF compared to the CDF of observed data that estimated, using Kaplan-Meier algorithm. The comparisons were evaluated by Goodness of fit (GOF) in 3 null hypothesis tests (Kolmogorov-Smirnov, Anderson-Darling and Chi-Square test). The best fit distribution was identified by minimum residual (R) index and maximum correlation (Cor) index based on difference value between the estimated and observed data. The Weibull distribution matched to the 118 rain gauges while 5 rain gauges were best fitted by the Gamma distribution.In hydrological processes, rainfall is one of the important components of water supply for human life. We considered how well the statistical distribution simulates rainfall intensity. We propose an asymmetric statistical probability distribution joined by zero-inflated to fit the daily continuous record of rainfall data in Thailand. The candidate statistical probabilities are General Pareto, Exponential, Beta, Gamma, Generalize extreme value, Extreme Value, Normal, Lognormal, Weibull and Rayleigh distribution. The daily data from 123 rain gauges in Thailand collected and removed in a given year, using the null value. The statistical distributions estimated on the statistical coefficient, using the maximum likelihood estimation (MLE) method and resulted in a cumulative density function (CDF). The CDF compared to the CDF of observed data that estimated, using Kaplan-Meier algorithm. The comparisons were evaluated by Goodness of fit (GOF) in 3 null hypothesis tests (Kolmogorov-Smirnov, Anderson-Darling and Chi-Square test). The best fit distribution was identified by minimum residual (R) index and maximum correlation (Cor) index based on difference value between the estimated and observed data. The Weibull distribution matched to the 118 rain gauges while 5 rain gauges were best fitted by the Gamma distribution

Applications of LiDAR measurement for road management

Since LiDAR (Light Detection And Ranging) is a suitable equipment for archiving three-dimensional surface data of any objects. Moreover, aerial LiDAR is used for the topographical survey, urban planning or forest measurement. On the other hand, ground based LiDAR has a potential for other purposes, such as landslide monitoring or landcover change monitoring. This paper reports method of landslide and landcover monitoring using LiDAR for road management. Firstly, landslide monitoring technique using ground based LiDAR was developed. The amount of movements of a landslide should be precisely measured using LiDAR. In this study, Choja landslide in Japan was measured by LiDAR with a measurement accuracy of 6 mm. The result showed movement of landslide was detected in almost 1cm accuracy. An intersection point calculation of three surfaces was very effective for the accurate measurement. However, this technique can adapt for artificial object which include a plane. This method should be expand for natural objects such as natural slope or natural cliff. Secondary, landcover change is also detected by ground based LiDAR. A wide area landcover should be classified automatically using LiDAR. The landcover change can be extracted by converting grid model and comparing the elevation of the objects. Vegetated areas are changing seasonally and annually. The land cover change was detected in Choja. The results showed agricultural land could be extracted. Classified trees and Rice fields showed higher accuracy. LiDAR also acquires RGB color information. The classification will improve by using RGB color information in near future

Estimation of Precipitable Water Using Numerical Prediction Data

Precipitable water (PW) is an important variable in the climate system. Interferometric synthetic aperture radar (InSAR) is a powerful remote sensing technique for measuring the topography and deformation of the Earth’s surface. However, variations in atmospheric water vapor content affect the accuracy of InSAR measurements. Therefore, it is important to understand the distribution of PW to mitigate atmospheric effects on remote sensing data. Herein, we estimated the PW distribution with high spatial resolution using numerical prediction data and digital elevation model (DEM) data from the Kanto region of Japan. We estimated the PW distribution at a resolution of 90 m from mesoscale model grid point value data while accounting for the difference in surface elevation within pixels using DEM data with a resolution of 90 m. The PW distribution at 90-m resolution could be estimated using the proposed method with good accuracy (root-mean-square difference within 4.0 mm) throughout the year. The proposed method provides high-resolution information on atmospheric water vapor content and its variation at 3-h intervals. This method is expected to be applicable in climate research and for the atmospheric correction of remote sensing data, which can improve the accuracy of remote sensing measurements

Residual Stress Assessment in Japanese FFS Code for Pressure Equipment, HPIS Z101

ABSTRACT The High Pressure Institute of Japan published the first edition of Fitness for Service Assessment Procedure in 2001, HPIS Z101. Z101 is currently being revised and updated including the addition of Level 2 Assessment which involves more detailed evaluation regarding the structural integrity of cracked pressure vessels or piping systems than Level 1 Assessment. One of the notable revisions of Level 1 and the additions in Level 2 are the weld residual stress assessment of welded components. In the Level 1 assessment, the simplified residual stress distribution was defined in the current version. After publishing the current version, the committee has made an additional investigation into the residual stress assessment in existing FFS codes such as R6 and API 579 and has also compared the data in the technical literature on residual stress. The existent FFS code contains a certain degree of safety in residual stress assessment by making conservative structural integrity assessments for cracked pressure vessels and piping to prevent unexpected failure. However, the definition of residual stress profiles on the surface is controversial. In addition, some simplified definitions in the FFS codes do not always evaluate the measured weld residual stress safely. In this paper, the contradictions and controversial issues regarding weld residual stress distributions are discussed. Furthermore, the draft of revised Z101 is explained

Modulation bandwidth improvement of III-V/Si hybrid MOS optical modulator by reducing parasitic capacitance

In this work, we numerically and experimentally examined the impact of parasitic capacitance on the modulation bandwidth of a III-V/Si hybrid metal-oxide-semiconductor (MOS) optical modulator. The numerical analysis revealed that the parasitic capacitance between the III-V membrane and the Si slab should be considered to achieve high-speed modulation, particularly in the case of a thick gate oxide. We also fabricated a high-speed InGaAsP/Si hybrid MOS optical modulator with a low capacitance using a SiO2-embedded Si waveguide. The fabricated device exhibited a modulation efficiency of 0.245 Vcm and a 3 dB bandwidth of up to 10 GHz. Clear eye patterns with 25 Gbps non-return-to-zero (NRZ) modulation and 40 Gbps 4-level pulse amplitude modulation (PAM-4) were obtained without pre-emphasis

Dust from Comet 209P/LINEAR during its 2014 Return: Parent Body of a New Meteor Shower, the May Camelopardalids

We report a new observation of the Jupiter-family comet 209P/LINEAR during its 2014 return. The comet is recognized as a dust source of a new meteor shower, the May Camelopardalids. 209P/LINEAR was apparently inactive at a heliocentric distance rh = 1.6 au and showed weak activity at rh < 1.4 au. We found an active region of <0.001% of the entire nuclear surface during the comet's dormant phase. An edge-on image suggests that particles up to 1 cm in size (with an uncertainty of factor 3-5) were ejected following a differential power-law size distribution with index q=-3.25+-0.10. We derived a mass loss rate of 2-10 kg/s during the active phase and a total mass of ~5x10^7 kg during the 2014 return. The ejection terminal velocity of millimeter- to centimeter-sized particles was 1-4 m/s, which is comparable to the escape velocity from the nucleus (1.4 m/s). These results imply that such large meteoric particles marginally escaped from the highly dormant comet nucleus via the gas drag force only within a few months of the perihelion passage.Comment: 18 pages, 4 figures, accepted on 2014 December 11 for publication in the Astrophysical Journal Letter

Cryogenic deuterium target experiments with the GEKKO XII, green laser system

Copyright 1995 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 2(6), 2495-2503, 1995 and may be found at http://dx.doi.org/10.1063/1.87121