University of Tehran
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You're the reason I get up to face each hectic day How did our lives get so consumed with nonsense on the way We used to take the time to laugh and play a game or two But now it seems we fight a lot and cry way too much too So when you go to sleep at night I'll slip in by your side I'll hold you close and squeeze you tight and feel amazing pride You're the one that I love best, it's very clear to see With every day I know I'm blessed that you're a part of me Now let's just try to slow it down and savor all that's past For that's what molds our future, and life moves way too fast.
Kharazmi University
k.n.toosi university of technology
22 bahman
An emerging new literature brings unique ideas from corporate finance to the study of international trade and investment. Insights about differences in the development of financial institutions across countries, the role of financial constraints, and the use of internal capital markets are proving central in understanding international economics. The ability to access financial capital to pay fixed and variable costs affects choices firms make regarding export entry and operations, and, as a consequence, influence aggregate trade patterns. Financial frictions and the use of internal capital markets shape decisions that multinationals make regarding production locations, integration, and corporate governance. This article surveys this recent research with the goal of highlighting the main themes it explores, the key results it establishes, and the leading open questions it raises. Stochastic differential equation (SDE) is a very important mathematical tool to describe complex systems in which noise plays an important role. SDEs have been widely used to study various nonlinear systems in biology, engineering, finance and economics, as well as physical sciences. Since a SDE can generate unlimited number of trajectories, it is a difficult problem to estimate model parameters based on experimental observations which may represent only one trajectory of the stochastic model. During the last decade substantial research efforts have been made to the development of effective methods for inferring parameters in SDE models. However, it is still a challenge to estimate parameters in SDE models from observations with large variations. In this work, we proposed to use the implicit numerical methods to simulate SDE models in order to generate stable trajectories for estimating parameters in stiff SDE models. In addition, we used the particle swarm optimization to search the optimal parameters from the parameter space that has a complex model error landscape. Numerical results suggested that the proposed algorithm is an effective approach to estimate parameters in SDE models.
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Sometimes a picture needs no words, Photography is the science, art and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film.