Moduli Space of Topological 2-form Gravity

We propose a topological version of four-dimensional (Euclidean) Einstein gravity, in which anti-self-dual 2-forms and an SU(2) connection are used as fundamental fields. The theory describes the moduli space of conformally self-dual Einstein manifolds. In the presence of a cosmological constant, we evaluate the index of the elliptic complex associated with the moduli space.Comment: 10pages, Latex (minor changes

Using data from connected thermostats to track large power outages in the United States

The detection of power outages is an essential activity for electric utilities. A large, national dataset of Internet-connected thermostats was used to explore and illustrate the ability of Internet-connected devices to geospatially track outages caused by hurricanes and other major weather events. The method was applied to nine major outage events, including hurricanes and windstorms. In one event, Hurricane Irma, a network of about 1000 thermostats provided quantitatively similar results to detailed utility data with respect to the number of homes without power and identification of the most severely affected regions. The method generated regionally uniform outage data that would give emergency authorities additional visibility into the scope and magnitude of outages. The network of thermostat-sensors also made it possible to calculate a higher resolution version of outage duration (or SAIDI) at a level of customer-level visibility that was not previously available

Integrable Top Equations associated with Projective Geometry over Z_2

We give a series of integrable top equations associated with the projective geometry over Z_2 as a (2^n-1)-dimensional generalisation of the 3D Euler top equations. The general solution of the (2^n-1)D top is shown to be given by an integration over a Riemann surface with genus (2^{n-1}-1)^2.Comment: 8 pages, Late

Integrable field theories derived from 4D self-dual gravity

We reformulate the self-dual Einstein equation as a trio of differential form equations for simple two-forms. Using them, we can quickly show the equivalence of the theory and 2D sigma models valued in infinite-dimensional group, which was shown by Park and Husain earlier. We also derive other field theories including the 2D Higgs bundle equation. This formulation elucidates the relation among those field theories

Visibility and aerosol measurement by diode-laser random-modulation CW lidar

Examples of diode laser (DL) random-modulation continuous wave (RM-CW) lidar measurements are reported. The ability of the measurement of the visibility, vertical aerosol profile, and the cloud ceiling height is demonstrated. Although the data shown here were all measured at night time, the daytime measurement is, of course, possible. For that purpose, accurate control of the laser frequency to the center frequency of a narrow band filter is required. Now a new system with a frequency control is under construction

Hybrid ECAL: Optimization and Related Developments

Hybrid ECAL is a cost-conscious option of electromagnetic calorimeter (ECAL) for particle flow calorimetry to be used in a detector of International Linear Collider (ILC). It is a combination of silicon-tungsten ECAL, which realizes high granularity and robust measurement of electromagnetic shower, and scintillator-tungsten ECAL, which gives affordable cost with similar performance to silicon. Optimization and a data acquisition trial in a test bench for the hybrid ECAL are described in this article.Comment: 7 pages, 4 figures, Talk presented at the International Workshop on Future Linear Colliders (LCWS14), Belgrade, Serbia, 6-10 October 201

Field Effect Transistor Based on KTaO3 Perovskite

An n-channel accumulation-type field effect transistor (FET) has been fabricated utilizing a KTaO3 single crystal as an active element and a sputtered amorphous Al2O3 film as a gate insulator. The device demonstrated an ON/OFF ratio of 10^4 and a field effect mobility of 0.4cm^2/Vs at room temperature, both of which are much better than those of the SrTiO3 FETs reported previously. The field effect mobility was almost temperature independent down to 200K. Our results indicate that the Al2O3 / KTaO3 interface is worthy of further investigations as an alternative system of future oxide electronics.Comment: 3 pages, 3 Postscript figures, submitted to Appl.Phys.Let

Ground-state electric quadrupole moment of 31Al

Ground-state electric quadrupole moment of 31Al (I =5/2+, T_1/2 = 644(25) ms) has been measured by means of the beta-NMR spectroscopy using a spin-polarized 31Al beam produced in the projectile fragmentation reaction. The obtained Q moment, |Q_exp(31Al)| = 112(32)emb, are in agreement with conventional shell model calculations within the sd valence space. Previous result on the magnetic moment also supports the validity of the sd model in this isotope, and thus it is concluded that 31Al is located outside of the island of inversion.Comment: 5 page