We show that a canonical transformation converts, up to a boundary term, a generic 2D dilaton gravity model into a bosonic string theory with a Minkowskian target space.

This study is an empirical attempt to find out whether under sanctions Iran’s trade direction has shifted away from Europe (trade policy of de-Europeanization) towards Asia (trade policy of Asianization). The analysis is conducted using a panel-gravity trade model to analyze bilateral trade pattern between Iran and 50 countries from the EU and Asia during the period 2006–2013. To this end, the ...

To address the problem of multi-target retrieval (MTR) of remote sensing images, this study proposes a new object-level feature representation model. The model provides an enhanced application image representation that improves the efficiency of MTR. Generating the model in our scheme includes processes, such as object-oriented image segmentation, feature parameter calculation, and symbolic ima...

The aim of this empirical study is to explore the trade-off model and pecking order model of capital structure. The investigation is performed using panel data procedures for a sample of 76 firms listed in Tehran Stock Exchange during 2007-2010.The study employs OLS regression model in examining the capital structure of firms in Iran. The study employs variables reflecting differing theoretical...

We show how a Metric Affine theory of Dilaton gravity can be reduced to an effective Riemannian Dilaton gravity model. A simple generalization of the Obukhov-Tucker-Wang theorem to Dilaton gravity is then presented. 04.20.-q, 04.40.-b, 04.50.+h, 04.62.+v [email protected]

Drawing on a new and comprehensive measure of logistics quality, our gravity model suggests logistics in the exporting and partner-country can have an important impact on bilateral exports. A one standard deviation improvement in the exporter’s logistics quality, which for example would improve Gabon to the level of Guinea, would raise exports by almost 60%. Landlocked countries’ exports depend...

abstract t his paper explains bilateral trade patterns between south korea and thirteen opec member countries over the period 1980-2014 using a gravity model. the estimation results show that the gravity equation fits the data reasonably well. we confirmed the existence of long term relationships between the bilateral trade flows and the main components of gravity model - gdp, income (gdp per c...

determination of trade-off, which they are feasible and similar variations on all of decision making units (dmu), is important issue in data envelopment analysis (dea). in this paper, we select these trade-offs based on an external evaluation of dmus such that the correlation between external evaluation and technical evaluation resulted from dea model is maximized. in fact, we sift the trade-of...

abstract this study uses gravity model to examine the most important determinants of was agricultural trade. to this aim, import and export statistics of iran agricultural products for the period 1380 to 1387 was provided from iran customs organization and other information was obtained from different internet bases. random effects estimating and hausman test ratio result in fixed effects model...