Variational Monte Carlo studies of a t-J model on an anisotropic triangular lattice

With the insulating phase of \kappa-(BEDT-TTF)_2X in mind, we study a t-J model on an anisotropic triangular lattice, where the hopping integral is t' in one of the three directions, using a variational Monte Carlo method. By changing the value of t'/t, we study the stability of superconducting (SC) states with d- and d+id-wave symmetries and of an antiferromagnetic (AF) state. As t'/t decreases from 1, the stable state immediately switches from the d+id wave to the d wave. The AF state is stabilized from the normal spin liquid state for t'/t\lsim 0.7 at half filling. We also take account of Nagaoka ferromagnetism and a phase separation.Comment: 4 pages, 3 figure

AJK2011-03076 EFFECTS OF WALL CONDITION OF A PLUNGING BODY ON SPLASH

ABSTRACT Splashes generated by hydrogel sphere were simulated numerically and experimentally for investigating the effects of slip like mucus of living things. Numerical simulation using MPS (Moving Particle Semi-implicit) method was carried out. We defined the slip ratio as the swelling degree of hydrogel and installed the slip ratio into the MPS method. The swelling degree is the ratio of the weight of water against that of hydrogel. We simulated the splashes generated by the hydrogel spheres which had the different swelling degree plunging into water. As the evaluation of swelling degree on the surface of actual hydrogel spheres we also tested by using the hydrogel spheres plunging into water experimentally. The height of splash as a result of reaction of the air cavity became higher according to the increase of the swelling degree. The speed of hydrogel sphere sinking in water tank was also quicker in the numerical simulation. The reason of these results was that the velocity of water around the hydrogel sphere became quicker due to the slip on the surface

Coupled simulation of vibration of violint and sound radiation in concert hall

The vibrations and the sound field around the body of an old violin made by Stradivari are studied in this paper, in which this violin is scanned using a micro-CT scanner to generate a highly precise geometric image. After the noise in the scanned data is eliminated using a computer-assisted design (CAD) software for post-processing, the geometric data are saved in the simulation software. Assuming the orthotropic properties of woods (spruce and maple), the major vibration modes of the violin, such as A0, center bout rotation, B1-, B1+, and the acoustic pressure level at the surface of the violin body are calculated using the finite element method. Next, using the sound pressure distribution at the surface of the instrument, the sound pressure spreading in a rectangular box simulating a concert hall is calculated with the open-source parallel acoustic analysis software: ADVENTURE Sound. It is concluded that the sound pressure from the violin is successfully simulated

スクワットの効果的トレーニング : 糖尿病に対するハイスクワットの試行

Background: Recent clinical problems in primary care medicine include metabolic syndrome (Met-S) as well as other problems, such as diabetes mellitus, locomotive syndrome (Loc-S) and flailty in middle-age to older people. Regarding exercise therapy for patients with Met-S and Loc-S, aerobic exercise and also resistance (anaerobic) exercise have been considered as necessary. Thus, simple and effective resistance exercise methods should be clarified. Subjects and Methods: The subjects were 61 patients (male 36, female 25) with diabetes mellitus (66.9 ± 13.5 years old, mean ± SD). Subjects were instructed to perform a continuous squat exercises 5 minutes in morning and evening every day for 6 months, using the small exercise equipment ‘HiSquat”. The movements included 1) walking or jogging, 2) inner thigh exercise, 3) outer thigh exercise, 4) straight thigh exercise. Parameters were height, body weight, body mass index (BMI), abdominal circumference, thigh circumference and blood HbA1c value. The treatment of the subjects were not changed during the 6 months. HbA1c value was compared between 0 and 6 months. Results: The fundamental data before the study were as follows: height 159.4 ± 8.4 cm, body weight 62.5 ± 13.8 kg, BMI 24.5 ± 4.7 kg/m2, abdominal circumference 86.8 ± 10.7 cm, thigh circumference 42.9 ± 6.4 cm, HbA1c 6.8 ± 0.9%. HbA1c value at 6 months was 6.4 ± 1.0%, with a statistically significant decrease of 0.4%. As for the correlation analyses, a positive significant correlation was observed between BMI and the thigh/height ratio, and a negative significant correlation was observed between age and thigh/waist ratio. Conclusion: In this study, the HbA1c value was significantly decreased, which suggests the exercise effect of HiSquat. Our study provides fundamental data for the value of waist/thigh circumference in the exercise therapy, and also the efficacy of HiSquat; consequently it suggests the efficacy of HiSquat use for Met-S, Loc-S and flailty, which are increasing concerns in anti-aging medicine of Japan