1,786 research outputs found

    Long run communication support based on diagnostic symptom to the eruption as key roles of volcanologists toward sleeping giant - Case studies from Bandai, Usu and Azores

    Get PDF
    Volcanic eruptions can occur after decades-centuries long dormancy as has been seen from the recent examples: Mount St. Helens 1980, Pinatubo 1991, Unzen 1991, Soufrière Hills volcano 1995, Chaitén 2008, and Eyjafjallajökull 2010. Bandai volcano, NE Japan experienced a large scale sector collapse in 1888 which killed 477 people. We study how this catastrophic event is looked back by scientists, government and the local people. During the recent decades, the cultural and educational activities led by the Bandai Volcano Eruption Memorial Museum play an important role in disseminating hazard knowledge to the local people. Many outreach activities have been carried out at schools and/or in the volcano as well as the delivery of the volcanic hazard map. The regional headquarters of JMA in Sendai is in charge of monitoring 18 active volcanoes in Tohoku district. The area has not experienced major eruptions for long time, however the high potentiality for the large-scale eruption above VEI 4-5 is remarked such as Chokai B.C. 466 and Towada 915. The last four eruption crisis of Usu volcano, northern Japan were advised always by a couple of geophysicists and volcanologists through face-to-face communication with local town officers and the residents. Fogo volcano, Azores, shows 452 years of eruption dormancy whereas the recent geophysical studies have revealed repeated intrusion episodes during the last decades. We study how the information flows from scientific community to the public in case of volcanic crisis. It is a very challenging task how to deal with sleeping giants. Facilitating awareness of volcanic risks by maintaining long run communication among scientists, local authority and residents/tourists is the key for mitigating large volcanic hazards with low probabilities. Scientific support should be aimed at building community where “the local residents could make their own contingency and evacuation plans (Surono, 2013)”

    Complete temporal mode characterization of non-Gaussian states by dual homodyne measurement

    Full text link
    Optical quantum states defined in temporal modes, especially non-Gaussian states like photon-number states, play an important role in quantum computing schemes. In general, the temporal-mode structures of these states are characterized by one or more complex functions called temporal-mode functions (TMFs). Although we can calculate TMF theoretically in some cases, experimental estimation of TMF is more advantageous to utilize the states with high purity. In this paper, we propose a method to estimate complex TMFs. This method can be applied not only to arbitrary single-temporal-mode non-Gaussian states but also to two-temporal-mode states containing two photons. This method is implemented by continuous-wave (CW) dual homodyne measurement and doesn't need prior information of the target states nor state reconstruction procedure. We demonstrate this method by analyzing several experimentally created non-Gaussian states

    New Neural Network Based Nonlinear and Multipath Distortion Equalizer for FTTA Systems

    Full text link

    Neutral Scalar Higgs Masses and Production Cross Sections in an Extended Supersymmetric Standard Model

    Full text link
    Upper bounds on the three neutral scalar Higgs masses are considered in the supersymmetric standard model with a gauge singlet Higgs field. When the lightest Higgs is singlet-dominated the second lightest Higgs is shown to lie near or below the theoretical upper bound on the lightest Higgs mass. We also consider detectability of these Higgs bosons at a future e+ee^+ e^- linear collider with s300\sqrt{s}\sim 300 GeV and show that at least one of the neutral scalar Higgs has a production cross section larger than 0.04~pb.Comment: Latex 9 pages + 5 figures (not included), KEK-TH-386, KEK preprint 93-204, CHIBA-EP-7
    corecore