On the global well-posedness of a class of Boussinesq- Navier-Stokes systems

In this paper we consider the following 2D Boussinesq-Navier-Stokes systems \partial_{t}u+u\cdot\nabla u+\nabla p+ |D|^{\alpha}u &= \theta e_{2} \partial_{t}\theta+u\cdot\nabla \theta+ |D|^{\beta}\theta &=0 \quad with $\textrm{div} u=0$ and $0<\beta<\alpha<1$. When $\frac{6-\sqrt{6}}{4}<\alpha< 1$, $1-\alpha<\beta\leq f(\alpha)$, where $f(\alpha)$ is an explicit function as a technical bound, we prove global well-posedness results for rough initial data.Comment: 23page

A new displacement-based approach to calculate stress intensity factors with the boundary element method

The analysis of cracked brittle mechanical components considering linear elastic fracture mechanics is usually reduced to the evaluation of stress intensity factors (SIFs). The SIF calculation can be carried out experimentally, theoretically or numerically. Each methodology has its own advantages but the use of numerical methods has be-come very popular. Several schemes for numerical SIF calculations have been developed, the J-integral method being one of the most widely used because of its energy-like formulation. Additionally, some variations of the J-integral method, such as displacement-based methods, are also becoming popular due to their simplicity. In this work, a simple displacement-based scheme is proposed to calculate SIFs, and its performance is compared with contour integrals. These schemes are all implemented with the Boundary Element Method (BEM) in order to exploit its advantages in crack growth modelling. Some simple examples are solved with the BEM and the calculated SIF values are compared against available solutions, showing good agreement between the different schemes

Differential-difference system related to toroidal Lie algebra

We present a novel differential-difference system in (2+1)-dimensional space-time (one discrete, two continuum), arisen from the Bogoyavlensky's (2+1)-dimensional KdV hierarchy. Our method is based on the bilinear identity of the hierarchy, which is related to the vertex operator representation of the toroidal Lie algebra \sl_2^{tor}.Comment: 10 pages, 4 figures, pLaTeX2e, uses amsmath, amssymb, amsthm, graphic

Lowering and raising operators for the free Meixner class of orthogonal polynomials

We compare some properties of the lowering and raising operators for the classical and free classes of Meixner polynomials on the real line

Pricing Strategy for Quasi-public Forest Tourism Park Case Study in Gunung Pancar Forest Tourism Park, Bogor Indonesia

The dynamic of 3-parties conflict of interests (investor, local people and government) in having actual income from the nature tourism park business in Indonesia became worse since a “very progressive” Government Regulation on Forestry Related Services Tariff (so called PP 12/2014) was issued. On one hand, everybody agrees to improve the 17 years old tariff regulation of PP 59/1998. On the other hand, the “unclear reason” of the new tariffs in PP 12/2014 has shocked many parties and created many difficulties while implemented. This paper studies visitors' expenditures and their willingness to pay (WTP) for every recreation services scenario by using contingent valuation method (CVM) survey with open-ended eliciting questionnaire instrument. Regarding the characteristic of Gunung Pancar Forest Tourism Park (GPFTP) the method was used to justify a reasonable and eligible ticket pricing strategy at the GPFTP as a quasi-public recreation park. The survey has also specifically addressed the reasonable ticket-price that aligns with the financial assumption of investor's business plan and local people's economic activities. Results of the survey show that the continuum of visitors' WTP is ranging from 3.4 times (as the response to scenario-1) up to 12.7 times (as the response to scenario-5) of the recent ticket price. The WTP of scenario-2, 3 and 4 are ranging from 4.7, 6.2 and 7.5 times, respectively. Furthermore, the results of Tobit Regression Analysis show that seven important variables are positively correlated, while six variables are negatively correlated with the WTP

Heavy rainfall events recorded in sediments of the TT Lake (southern-central Tibetan Plateau) since AD 440

Abstract HKT-ISTP 2013 B

Broadband X-ray spectrum of XTE J1550-564 during 2003 outburst

Results of broadband INTEGRAL and RXTE observations of the Galactic microquasar XTE J1550-564 during outburst in spring 2003 are presented. During the outburst the source was found in a canonical low/hard spectral state.Comment: 5 pages, 3 figures. Accepted for publication in Astronomy Letter

Revisiting vertical structure of neutrino-dominated accretion disks: Bernoulli parameter, neutrino trapping and other distributions

We revisit the vertical structure of neutrino dominated accretion flows (NDAFs) in spherical coordinates with a new boundary condition based on the mechanical equilibrium. The solutions show that NDAF is significantly thick. The Bernoulli parameter and neutrino trapping are determined by the mass accretion rate and the viscosity parameter. According to the distribution of the Bernoulli parameter, the possible outflow may appear in the outer region of the disk. The neutrino trapping can essentially affect the neutrino radiation luminosity. The vertical structure of NDAF is like a "sandwich", and the multilayer accretion may account for the flares in gamma-ray bursts.Comment: 7 pages, 2 figures, Accepted for publication in Astrophysics & Space Scienc

Egorov's theorem for transversally elliptic operators on foliated manifolds and noncommutative geodesic flow

The main result of the paper is Egorov's theorem for transversally elliptic operators on compact foliated manifolds. This theorem is applied to describe the noncommutative geodesic flow in noncommutative geometry of Riemannian foliations.Comment: 23 pages, no figures. Completely revised and improved version of dg-ga/970301