Damages caused by 3/11 Great East Japan earthquake on coastal drainage pumping stations along Sendai bay

On March 11, 2011, a tsunami struck low-lying land along Sendai Bay, where no tsunami had hit in the past 200 years. These coastal lowlands were equipped with drainage pumping stations for paddy areas, but the pumping stations were destroyed by the tsunami, thus preventing drainage of the sea water inundation.There are two kinds of pumps, motor and diesel pumps. Even diesel pumps need electricity to start up and control their power. If a pump is inundated by salt water, all electric parts will be short-circuited. Although the diesel mechanisms can be reused after being washed by fresh water, the electric parts of both types of pump must be replaced. The switchboard for the pumps must also be replaced. If damages are caused only by salt inundation, the electric parts of both types of pump must be replaced. Temporary recovery was done by manually controlling the pumps because the automatic pump control system was difficult to restore. The mean recovery time was one month for electric pumps and two months for diesel pumps. For pumps that were broken by external force, quick recovery was abandoned.Past studies on tsunami have shown that concrete structures are strong enough to withstand tsunami surges. In the present study, a few concrete pumping stations located near the coast were damaged. The damages to buildings were mainly governed by the type of material and location on the coast. At some pumping stations, the tank for desorption prevented external forces from acting on the buildings.These results show that the tsunami safety of drainage pumping stations could be improved by increasing the resistance to salt inundation and appropriately locating the tank for desorption

Influence of climate change on storm surges in the Ariake sea

The influence of climate change on storm surges in the Ariake Sea was evaluated using the stochastic\ud typhoon model. The Ariake Sea is located in the middle of Kyushu Island, Japan and has been attacked by severe\ud typhoons many times. There are many lowland coastal farmlands along the coastline of the Ariake Sea as a result of\ud many reclamation projects since ancient times. These coastal farmlands are at risk of even more severe storm surges due\ud to typhoons caused by climate change. The deviations of tides due to storm surges were simulated by an experimental\ud typhoon model employing the Myers model. The stochastic typhoon model generated the tracks and attributes of\ud typhoons over the next 2,000 years. Meanwhile, the tracks of typhoons in the case of the climate after climate change\ud were generated by shifting the start points of typhoons 0.9 degrees further north and 1.9 degrees further east. The\ud number of typhoons after climate change was set to 0.79 times that of typhoons in the present climate. These changes in\ud the tracks and number of typhoons in the future were decided according to the results of numerical simulations of\ud climate change using the AGCM model based on the A1B scenario. The non-exceedance probabilities of the yearmaximum\ud anomaly rise were compared to evaluate the change due to climate change. The simulation suggested that the\ud height of the year-maximum anomaly rise due to storm surges in the future climate will be similar to or slightly lower\ud than the present height

Multi-focal Metabolic Disturbances in Human Brain at a Chronic Stage of Stroke Studied with 18FDG and Positron Emission Tomography

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A Study of Dopamine Metabolism in a Patient with Juvenile Parkinsonism by Positron Emission Tomography

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A Study of Sum Peak Method in Biological Substances by Using 111In

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Characterization of electrostatic shock in laser-produced optically-thin plasma flows using optical diagnostics

We present a method for evaluating the properties of electrostatic shock in laser-produced plasmas by using optical diagnostics. A shock is formed by a collimated jet in counter-streaming plasmas in nearly collisionless condition, showing the steepening of the transition width in time. In the present experiment, a streaked optical pyrometry was applied to evaluate the electron density and temperatures in the upstream and downstream regions of the shock so that the shock conditions are satisfied, by assuming thermal bremsstrahlung emission in optically thin plasmas. The derived electron densities are nearly consistent with those estimated from interferometry

Heralded quantum memory for single-photon polarization qubits

We propose a scheme to implement a heralded quantum memory for single-photon polarization qubits with a single atom trapped in an optical cavity. In this scheme, an injected photon only exchanges quantum state with the atom, so that the heralded storage can be achieved by detecting the output photon. We also demonstrate that the scheme can be used for realizing the heralded quantum state transfer, exchange and entanglement distribution between distant nodes. The ability to detect whether the operation has succeeded or not is crucial for practical application.Comment: 5 pages, 6 figure