INUNDATION OF THE CHIKUMA RIVER DUE TO THE TYPHOON HAGIBIS IN OCTOBER 2019 AND ISSUES OF EFFECTIVENESS IN EVACUATION PLANS OF ELDERLY WELFARE FACILITIES FOR THE LARGEST EXPECTED RAINFALL

In the heavy rain disaster caused by typhoon HAGBIS in 2019, the collapse of the Chikuma River embankment caused widespread inundation damage in Nagano City. We conducted an inundation trace survey, the flood inundation calculation, and interview surveys of 6 elderly welfare facilities which were damaged by inundation. From the results, the relationships between the evacuation behavior of each facility and the inundation process were analyzed. In addition, we considered the issues of evacuation safety planning in the event of the largest expected flood

Laminin γ1 C-terminal Glu to Gln mutation induces early postimplantation lethality

Daiji Kiyozumi, Yukimasa Taniguchi, Itsuko Nakano, Junko Toga, Emiko Yagi, Hidetoshi Hasuwa, Masahito Ikawa, and Kiyotoshi Sekiguchi, "Laminin γ1 C-terminal Glu to Gln mutation induces early postimplantation lethality", Life Science Alliance, Vol.1, No.5, e201800064, Life Science Alliance, 201

Discriminating the Progenitor Type of Supernova Remnants with Iron K-Shell Emission

Supernova remnants (SNRs) retain crucial information about both their parent explosion and circumstellar material left behind by their progenitor. However, the complexity of the interaction between supernova ejecta and ambient medium often blurs this information, and it is not uncommon for the basic progenitor type (Ia or core-collapse) of well-studied remnants to remain uncertain. Here we present a powerful new observational diagnostic to discriminate between progenitor types and constrain the ambient medium density of SNRs solely using Fe K-shell X-ray emission. We analyze all extant Suzaku observations of SNRs and detect Fe K alpha emission from 23 young or middle-aged remnants, including five first detections (IC 443, G292.0+1.8, G337.2-0.7, N49, and N63A). The Fe K alpha centroids clearly separate progenitor types, with the Fe-rich ejecta in Type Ia remnants being significantly less ionized than in core-collapse SNRs. Within each progenitor group, the Fe K alpha luminosity and centroid are well correlated, with more luminous objects having more highly ionized Fe. Our results indicate that there is a strong connection between explosion type and ambient medium density, and suggest that Type Ia supernova progenitors do not substantially modify their surroundings at radii of up to several parsecs. We also detect a K-shell radiative recombination continuum of Fe in W49B and IC 443, implying a strong circumstellar interaction in the early evolutionary phases of these core-collapse remnants.Comment: Accepted by ApJL; 5 pages with just 1 table and 1 figur

Dual-Matrix Domain-Wall: A Novel Technique for Generating Permutations by QUBO and Ising Models with Quadratic Sizes

The Ising model is defined by an objective function using a quadratic formula of qubit variables. The problem of an Ising model aims to determine the qubit values of the variables that minimize the objective function, and many optimization problems can be reduced to this problem. In this paper, we focus on optimization problems related to permutations, where the goal is to find the optimal permutation out of the $n!$ possible permutations of $n$ elements. To represent these problems as Ising models, a commonly employed approach is to use a kernel that utilizes one-hot encoding to find any one of the $n!$ permutations as the optimal solution. However, this kernel contains a large number of quadratic terms and high absolute coefficient values. The main contribution of this paper is the introduction of a novel permutation encoding technique called dual-matrix domain-wall, which significantly reduces the number of quadratic terms and the maximum absolute coefficient values in the kernel. Surprisingly, our dual-matrix domain-wall encoding reduces the quadratic term count and maximum absolute coefficient values from $n^3-n^2$ and $2n-4$ to $6n^2-12n+4$ and $2$, respectively. We also demonstrate the applicability of our encoding technique to partial permutations and Quadratic Unconstrained Binary Optimization (QUBO) models. Furthermore, we discuss a family of permutation problems that can be efficiently implemented using Ising/QUBO models with our dual-matrix domain-wall encoding.Comment: 26 pages, 9 figure

Depth profiles of radioactive cesium in soil using a scraper plate over a wide area surrounding the Fukushima Dai-ichi Nuclear Power Plant, Japan

AbstractDuring the Fukushima Dai-ichi Nuclear Power Plant (NPP) accident, radioactive cesium was released in the environment and deposited on the soils. Depth profiles of radioactive cesium in contaminated soils provide useful information not only for radiation protection and decontamination operations but also for geoscience and radioecology studies. Soil samples were collected using a scraper plate three times between December 2011 and December 2012 at 84 or 85 locations within a 100-km radius of the Fukushima Dai-ichi NPP. In most of the obtained radioactive cesium depth profiles, it was possible to fit the concentration to a function of mass depth as either an exponential or hyperbolic secant function. By using those functions, following three parameters were estimated: (i) relaxation mass depth β (g cm−2), (ii) effective relaxation mass depth βeff (g cm−2), which is defined for a hyperbolic secant function as the relaxation mass depth of an equivalent exponential function giving the same air kerma rate at 1 m above the ground as the inventory, and (iii) 1/10 depth L1/10 (cm), at which the soil contains 90% of the inventory. The average β value (wet weight) including ones by hyperbolic secant function in December 2012, was 1.29 times higher than that in December 2011. In fact, it was observed that depth profiles at some study sites deviated from the typical exponential distributions over time. These results indicate the gradual downward migration of radioactive cesium in the soils. The L1/10 values in December 2012 were summarized and presented on a map surrounding the Fukushima Dai-ichi NPP, and the average value of L1/10 was 3.01 cm (n = 82) at this time. It was found that radioactive cesium remained within 5 cm of the ground surface at most study sites (71 sites). The sech function can also be used to estimate the downward migration rate V (kg m−2 y−1). The V values in December 2012 (n = 25) were in good agreement with those found by a realistic approach using a diffusion and migration model. Almost all values ranged between 1.7 and 9.6 kg m−2 y−1 in this study