Seismic Hazard Estimation Based on Non-Poisson Earthquake Occurrences

A non-Poisson earthquake occurrence model for seismic hazard estimation is developed to account for the periodicity and the nonstationarity in seismic activities. The model consists of a renewal process model for major fault systems and a nonstationary Poisson-type model for secondary seismic sources, the latter being dominated by the former. The model is identified on the basis of the historical earthquake data for the Kinki District in the western part of Japan, containing the Kyoto-Osaka-Kobe metropolitan area. A simulation model for seismic hazard estimations (ground acceleration and velocity are dealt with) is then developed by combining the non-Poisson earthquake occurrence model and probabilistic attenuation rules. On the basis of the results of the simulation, the significance of the periodicity and the nonstationarity of seismic activities in assessing the seismic risk is discussed

Successful laparoscopic resection of virilizing ovarian steroid cell tumor, not otherwise specified, in a 22-year-old woman: a case report and evaluation of the steroidogenic pathway

Objective: Ovarian steroid cell tumor (SCT) is a rare tumor with steroid-producing ability. We report a 22-year-old woman with secondary amenorrhea and hirsutism caused by an ovarian SCT-not otherwise specified (NOS), who underwent successfully laparoscopic resection of the tumor. Case report: A 22-year-old null gravida woman presented to a hospital, having amenorrhea for 18 months and increasing facial hair. Physical examination revealed obesity (body mass index, 37.3 kg/m2) with evident facial and trunk hair. Total and free serum testosterone, and dehydroepiandrosterone sulfate levels were found to be elevated. Levels of serum adrenocorticotropic hormone, gonadotropins, cortisol, aldosterone, and ovarian steroids were observed to be within reference intervals. Although polycystic ovaries were not found, a hyperechogenic solid tumor (3 cm) was detected on transvaginal ultrasonography. Laparoscopic resection of the tumor was performed. One month post-surgery, total and free testosterone levels were observed to have decreased, and menstruation resumed two months thereafter. The patient was histologically diagnosed with ovarian SCT-NOS. Expression of ovarian steroidogenic enzymes, which are related to hyperandrogenism, was observed. No disease recurrence has been reported for more than 5 years post-surgery

Physical properties of the Dome Fuji deep ice core (review)

Recent results of physical analyses of the Dome Fuji ice core are summarized with special attention to new methods introduced in the present studies. Microphysical processes which affect the ice core records are reviewed to better understand the paleoclimatic and paleoenvironmental signals stored

Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon

A search for new isotopes using in-flight fission of a 345 MeV/nucleon 238U beam has been carried out at the RI Beam Factory at the RIKEN Nishina Center. Fission fragments were analyzed and identified by using the superconducting in-flight separator BigRIPS. We observed 45 new neutron-rich isotopes: 71Mn, 73,74Fe, 76Co, 79Ni, 81,82Cu, 84,85Zn, 87Ga, 90Ge, 95Se, 98Br, 101Kr, 103Rb, 106,107Sr, 108,109Y, 111,112Zr, 114,115Nb, 115,116,117Mo, 119,120Tc, 121,122,123,124Ru, 123,124,125,126Rh, 127,128Pd, 133Cd, 138Sn, 140Sb, 143Te, 145I, 148Xe, and 152Ba

Effects of surface states on control characteristics of nano-meter scale Schottky gates formed on GaAs

Effects of surface states on gate control characteristics of nano-meter scale Schottky gates formed on GaAs are investigated both theoretically and experimentally. Special sample structures are used. They are metal–insulator–semi-conductor structures having nano-meter scale Schottky dot arrays for capacitance–voltage (C–V) measurements and metal–semi-conductor field effect transistor structures having nano-meter scale grating Schottky gates for current–voltage (I–V) measurements. Measured C–V and I–V results are compared with results of theoretical calculation on a computer. The effects of surface states are found to be two-fold. Namely, it is shown that control characteristics of nano-meter scale Schottky gates are strongly degraded by the presence of Fermi level pinning caused by surface states on the free surface surrounding the gate. It is also shown that a significant amount of gate-induced lateral charging of surface states takes place around the gate periphery, effectively increasing the gate dimension. These results indicate the critical importance of control of surface states in nano-devices using nano-meter scale Schottky gates

Searching for Mobile Intruders in a Polygonal Region by a Group of Mobile Searchers

The problem of searching for mobile intruders in a polygonal region by mobile searchers is considered. A searcher can move continuously inside a polygon holding a flashlight that emits a single ray of light whose direction can be changed continuously. The visibility of a searcher at any time instant is limited to the points on the ray. The intruders can move continuously with unbounded speed. We denote by ps(P ) the polygon search number of a simple polygon P , which is the number of searchers necessary and sufficient to search P . Let n, r, b and g be the number of edges, the number of reflex vertices, the bushiness, and the size of a minimum guard set of P , respectively. In this paper, we present matching upper and (worst case) lower bounds of 1 + blog 3 (2b + 1)c on ps(P ). Also upper bounds on ps(P ) in terms of n; r and g are presented; ps(P ) 1 + blog 3 (n \Gamma 3)c; ps(P ) 1 + blog 3 rc, and ps(P ) 2 + dlog 2 ge. These upper bounds are tight or almost tight in the worst c..