1,588 research outputs found
Preparing for Large Natural Catastrophes: The current state and challenges of earthquake insurance in Japan
Global incidents of major natural catastrophes are becoming increasingly common in recent years. Seismological research has shown earthquake-prone Japan to be at particular risk from not only inland earthquakes, but also from repeat incidents of major earthquakes such as the Tokai, Tonankai, and Nankai earthquakes. In such an eventuality, earthquake insurance is expected to play a part in ex-post recovery efforts from the damage caused by these earthquakes, with the Japanese government developing special support programs. The previously low penetration rate of earthquake insurance in Japan, however, meant that it did not play a significant role in recovery efforts following the 1995 Great Hanshin-Awaji Earthquake. Despite recent progress in improving the system and an increasing awareness of the risks from earthquakes, the penetration rate of earthquake insurance in Japan remains at approximately 20%. In this study we discuss the current state and issues of earthquake insurance in Japan.Earthquake Insurance; natural catastrophes; Hanshin-Awaji Earthquake
SO(10) Group Theory for the Unified Model Building
The complete tables of Clebsh-Gordan (CG) coefficients for a wide class of
SO(10) SUSY grand unified theories (GUTs) are given. Explicit expression of all
states and corresponding multiplets under standard model gauge group G_{321} =
SU(3)_C x SU(2)_L x U(1)_Y, necessary for evaluation of the CG coefficients are
presented. The SUSY SO(10) GUT model considered here incudes most of the Higgs
irreducible representations usually used in the literature: 10, 45, 54, 120,
126 126-bar and 210. Mass matrices of all G_{321} multiplets are found for the
most general superpotential. These results are indispensible for the precision
calculations of the gauge coupling unification and proton decay, etc.Comment: 62 pages, LaTeX, we comment on results of hep-ph/0402122 and
hep-ph/0405074; typos corrected;references updated, small improvements of the
tex
Neutralino dark matter in brane world cosmology
The thermal relic density of the neutralino dark matter in the brane world
cosmology is studied. Since the expansion law at a high energy regime in the
brane world cosmology is modified from the one in the standard cosmology, the
resultant relic density can be altered. It has been found that, if the five
dimensional Planck mass is lower than TeV, the brane world
cosmological effect is significant at the decoupling time and the resultant
relic density is enhanced. We calculate the neutralino relic density in the
Constrained Minimal Supersymmetric Standard Model (CMSSM) and show that the
allowed region is dramatically modified from the one in the standard cosmology
and eventually disappears as is decreasing. We also find a new lower
bound on TeV based on the neutralino dark matter hypothesis,
namely the lower bound in order for the allowed region of the neutralino dark
matter to exist.Comment: 12 pages, 8 figure
Light wino dark matter in brane world cosmology
The thermal relic density of the wino-like neutralino dark matter in the
brane world cosmology is studied. The expansion law at a high energy regime in
the brane world cosmology is modified from the one in the standard cosmology,
and the resultant relic density can be enhanced if the five dimensional Planck
mass is low enough. We calculate the wino-like neutralino relic density
in the anomaly mediated supersymmetry breaking scenario and show that the
allowed region is dramatically modified from the one in the standard cosmology
and the wino-like neutralino with mass of order 100 GeV can be a good candidate
for the dark matter. Since the allowed region disappears eventually as is
decreasing, we can find a lower bound on TeV according to the
neutralino dark matter hypothesis, namely the lower bound in order for the
allowed region of the neutralino dark matter to exist.Comment: 16 pages, 9 figures, final versio
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