Fermi Surface of 3d^1 Perovskite CaVO3 Near the Mott Transition

We present a detailed de Haas van Alphen effect study of the perovskite CaVO3, offering an unprecedented test of electronic structure calculations in a 3d transition metal oxide. Our experimental and calculated Fermi surfaces are in good agreement -- but only if we ignore large orthorhombic distortions of the cubic perovskite structure. Subtle discrepancies may shed light on an apparent conflict between the low energy properties of CaVO3, which are those of a simple metal, and high energy probes which reveal strong correlations that place CaVO3 on the verge of a metal-insulator transition.Comment: 4 pages, 4 figures (REVTeX

Uniaxial-Pressure induced Ferromagnetism of Enhanced Paramagnetic Sr3Ru2O7

We report a uniaxial pressure-dependence of magnetism in layered perovskite strontium ruthenate Sr3Ru2O7. By applying a relatively small uniaxial pressure, greater than 0.1 GPa normal to the RuO2 layer, ferromagnetic ordering manifests below 80 K from the enhanced-paramagnet. Magnetization at 1 kOe and 2 K becomes 100 times larger than that under ambient condition. Uniaxial pressure dependence of Curie temperature T_C suggests the first order magnetic transition. Origin of this uniaxial-pressure induced ferromagnetism is discussed in terms of the rotation of RuO6 octahedra within the RuO2 plane.Comment: 8 pages, 3 figures. to be published in Journal of the Physical Society of Japan, vol.73, No.5 (2004

Analytical thermal modeling and calibration method for lithium-ion batteries

The lithium-ion battery is an essential component to drive mobile systems. The battery behavior varies depending on its thermal conditions. Thus, to optimize the lifetime performance, it is important to estimate the inner temperatures of battery. This paper proposes a new analytical method to estimate the inner temperatures of battery with the use of the Joule heat as well as the Entropy heat. An evaluation is also attempted by means of a real battery sample.Papers presented at the 13th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Portoroz, Slovenia on 17-19 July 2017 .International centre for heat and mass transfer.American society of thermal and fluids engineers

Millihertz Quasi-periodic Optical Oscillations in 4U 0614+091

We report the discovery of a 1mHz optical quasi-periodic oscillation (QPO) in the candidate ultracompact low-mass X-ray binary 4U 0614+091. The ultra-low frequency QPO has no X-ray counterpart in contemporaneous RXTE/PCA data and is likely a signature of structure in the accretion disk. The QPO can be reasonably fitted with a single sine wave but with a phase jump part way through the observation, indicating that it is not coherent.We also identify a 48 min modulation, approximately consistent with the suggested orbital period of O'Brien (2005) and Shahbaz et al. (2008). If this is indeed orbital, it supports an identification of 4U 0614+091 as an ultra-compact source.Comment: 7 pages, 5 figures, accepted for publication in Monthly Notices of the Royal Astronomical Societ

Sub-nanosecond passively Q-switched Yb : YAG/Cr4+: YAG sandwiched microchip laser

We report on laser-diode pumped low-threshold, and compact passively Q-switched Yb:YAG microchip lasers, with Cr4+:YAG crystals as the saturable absorbers. The laser threshold at the fundamental wavelength of 1.03 mu m is as low as 0.25 W, and the slope efficiency is as high as 36.8%, and the optical-to-optical efficiency is as high as 27% for the 95% initial transmission of the Cr4+:YAG crystal. A pulse width of 1.35 ns and peak power of over 8.2 kW was obtained. Using a 5 mm thick KTP crystal as the second-harmonic generation medium, 514.7 nm green light of 155 mW power was generated. The pulse duration of 480 ps was generated at 1.03 mu m by using 85% of the initial transmission of the Cr4+:YAG saturable absorber. Stable single-longitudinal-mode oscillation and wide-separated multi-longitudinal-mode oscillation due to the etalon effect of the Cr4+:YAG thin plate was achieved at different pump power levels

Band-width control in a perovskite-type 3d^1 correlated metal Ca_1-xSr_xVO_3. II. Optical spectroscopy investigation

Optical conductivity spectra of single crystals of Ca_1-xSr_xVO_3 have been studied to elucidate how the electronic behavior depends on the strength of the electron correlation without changing the nominal number of electrons per vanadium atom. The effective mass deduced by the analysis of the Drude-like contribution do not show critical enhancement, even though the system is close to the Mott transition. Besides the Drude-like contribution, two anomalous features were observed in the optical conductivity spectra of the intraband transition within the 3d band. These features can be assigned to transitions involving the incoherent and coherent bands near the Fermi level. The large spectral weight redistribution in this system, however, does not involve a large mass enhancement.Comment: 12 pages in a Phys. Rev. B camera-ready format with 16 EPS figures embedded. LaTeX 2.09 source file using "camera.sty" and "prbplug.sty" provided by N. Shirakawa. For OzTeX (Macintosh), use "ozfig.sty" instead of "psfig.sty". "ozfig.sty" can be also obtained by e-mail request to N. Shirakawa: . Submitted to Phys. Rev. B. See "Part I (by Inoue et al.)" at cond-mat/980107

How do experts recognize schizophrenia: the role of the disorganization symptom

Objective: Research on clinical reasoning has been useful in developing expert systems. These tools are based on Artificial Intelligence techniques which assist the physician in the diagnosis of complex diseases. The development of these systems is based on a cognitive model extracted through the identification of the clinical reasoning patterns applied by experts within the clinical decision-making context. This study describes the method of knowledge acquisition for the identification of the triggering symptoms used in the reasoning of three experts for the diagnosis of schizophrenia. Method: Three experts on schizophrenia, from two University centers in Sao Paulo, were interviewed and asked to identify and to represent the triggering symptoms for the diagnosis of schizophrenia according to the graph methodology. Results: Graph methodology showed a remarkable disagreement on how the three experts established their diagnosis of schizophrenia. They differed in their choice of triggering-symptoms for the diagnosis of schizophrenia: disorganization, blunted affect and thought disturbances. Conclusions: The results indicate substantial differences between the experts as to their diagnostic reasoning patterns, probably under the influence of different theoretical tendencies. The disorganization symptom was considered to be the more appropriate to represent the heterogeneity of schizophrenia and also, to further develop an expert system for the diagnosis of schizophrenia.2815