The shear viscosity of holographic superfluids

We study the ratio of the shear viscosity to the entropy density for various holographic superfluids. For the s-wave case, the ratio has the universal value 1/(4pi) as in various holographic models. For the p-wave case, there are two shear viscosity coefficients because of the anisotropic boundary spacetime, and one coefficient has the universal value. For the (p+ip)-wave case, the existing technique is not applicable since there is no tensor mode of metric perturbations which decouples from Yang-Mills perturbations. Our results indicate that the shear viscosity does not show a singular behavior at the critical point for holographic superfluids.Comment: 22 pages, PTPTe

PIH and ROT alternative in view of the intertemporal non-separability of preferences: empirical findings from a Japanese panel data

This paper describes an empirical investigation into the permanent income hypothesis (PIH) and the rule-of-thumb (ROT) alternative hypothesis, both of which allow for the intertemporal non-separability of preferences in the sense that past consumption of the PIH consumers has influence on their current utility. The data used in this study is a Japanese aggregate panel data processed with the Family Income and Expenditure Survey (FIES) for the period 1981-2002, and the GMM estimations for the panel data are carried out for spans within the period. The results demonstrate that the PIH holds for the bubble span 1988-1993 and the serious deflation span 1997-2002, while the ROT alternative holds for the post-bubble depression span 1993-1998.Permanent income hypothesis; Rule-of-thumb alternative hypothesis; Intertemporal non-separability of preferences; Panel data; Generalized method of moments

Grouth of G.P. zones in Al-Zn alloy

Metastable values of electrical resistivity, P(E)' obtained during isothermal ageing differs in each experimental run even when the conditions of quenching and ageing were carefully kept constant. This phenomenon is considered to result from the competitive growth of G.P.zones. The range of the values of P(E) under the same conditions of heat treatments were examined, and the results obtained are as follows: (1) Metastable values of resistivity, P(E), during ageing at 70℃ after quenching from 300℃ were in rather narrow range. On the other hand, the width of the range obtained during ageing at 50℃ was wide. (2) When the specimens were aged at first at 70℃ until the maximum values of resistivity, P(M), being reached and then aged at 50℃ for long time, the metastable values of resistivity, PE*, were obtained. And the width of discrepancy of values of P(E)* was nearly equal to that of P(E) which was obtained in the case of isothermal ageing at 70℃ after quenching from 300℃. (3) It may be concluded that the width of discrepancy of values of P(E)* becomes smaller since the width of discrepancy of the number of G.P.zones for all experiments which can grow through competitive growth is made small by 70℃ ageing than that immediately after quenching from 300℃

Coalition structure generation in cooperative games with compact representations

This paper presents a new way of formalizing the coalition structure generation problem (CSG) so that we can apply constraint optimization techniques to it. Forming effective coalitions is a major research challenge in AI and multi-agent systems. CSG involves partitioning a set of agents into coalitions to maximize social surplus. Traditionally, the input of the CSG problem is a black-box function called a characteristic function, which takes a coalition as input and returns the value of the coalition. As a result, applying constraint optimization techniques to this problem has been infeasible. However, characteristic functions that appear in practice often can be represented concisely by a set of rules, rather than treating the function as a black box. Then we can solve the CSG problem more efficiently by directly applying constraint optimization techniques to this compact representation. We present new formalizations of the CSG problem by utilizing recently developed compact representation schemes for characteristic functions. We first characterize the complexity of CSG under these representation schemes. In this context, the complexity is driven more by the number of rules than by the number of agents. As an initial step toward developing efficient constraint optimization algorithms for solving the CSG problem, we also develop mixed integer programming formulations and show that an off-the-shelf optimization package can perform reasonably well

ケイド ニ カキョウ シ アッシュク ハイコウ ケッショウカ サセタ ジンコウ カンセツヨウ UHMWPE ノ コウゾウ ト リキガクテキ セイシツ ニ カンスル ケンキュウ

京都大学0048新制・課程博士博士(工学)甲第8932号工博第2023号新制||工||1202(附属図書館)UT51-2001-F262京都大学大学院工学研究科高分子化学専攻(主査)教授 岩田 博夫, 教授 粷谷 信三, 教授 堤 定美学位規則第4条第1項該当Doctor of EngineeringKyoto UniversityDFA

Development of super broadband interferometer in FIR

We are developing the super broad band interferometer by applying the Fourier Transform Spectrometer(FTS) to aperture synthesis system in mm and sub-mm bands. We have constructed a compact system based on the Martin and Puplett type Fourier Transform spectrometer (MP-FT). We call this equipment Multi-Fourier Transform interferometer (MuFT). The band width of the system can be extended as large as one wants contrary to the severely limited band width of the usual interferometer due to the speed of the AD converter. The direct detectors, e.g. bolometer, SIS video detector, can be used as the focal plane detectors. This type of detectors have a great advantage in FIR band since they are free from the quantum limit of the noise which limits the sensitivity of the heterodyne detectors used in the usual interferometers. Further, the direct detectors are able to make a large format array contrary to the heterodyne detectors for which construction of a large format array is practically difficult. These three characteristics make one be possible to develop high sensitive super broad band FIR interferometer with wide field of view. In the laboratory experiments, we have succeeded in measuring the spectroscopically resolved 2D image of the source in 150GHz-900GHz band. The future application of this technique to the observations from the space could open new interesting possibilities in FIR astronomy.Comment: 9 pages, presented at the Glasgow SPIE conference "Optical, Infrared, and Millimeter Space Telescopes", to appear in Proc. SPIE, vol. #5487-20

Numerical Study on Deformation Behavior of Rigid-Plastic Inhomogeneous Material Using Three-Dimensional Models

It is important to study the microscopic deformation behavior of inhomogeneous material, for most engineering materials are inhomogeneous. The aim of the present study is to clarify by numerical analysis some features of microscopic plastic strain distributions, the mean flow stress and the material factors affecting on it. The rigid-plastic solution is important not only for plastic deformation problems with large strain, but also for creep deformation problems through the plastic analogy in the creep analysis. The effects of material parameter and loading conditions on the deformation behavior of the material are examined and discussed based on the result of calculation. The effects of the aspect ratio of the inhomogeneous regions on the deformation mode are studied. The patterns of the strain concentration and the averaged flow stress of the inhomogeneous material are also discussed. The results of rigid-plastic material are compared with those of the elastic material