studying risk and frequency analysis of flood is done in order to design structures located in floody lands. in hydrological and water resources engineering projects, first of all, we should determine frequency of this phenomenon- their return period. in this research, the method of planning, the cumulative freguency curve is explained and probability and return period and errors concerning sma...

In this paper we study closed-loop supply chain models for a high-tech product which is featured with a short life-cycle and volatile demand. We focus on the manufacturer's choice of three alternative reverse channel structures for collecting the used product from consumers for remanufacturing: (1) the manufacturer collects the used product directly; (2) the retailer collects the used product f...

This paper investigates the conditional correlations and volatility spillovers between the dollar exchange rate return, gold coin return and crude oil return to stock index return. Monthly returns in the 144 observations (2005 - 2017) are analyzed by constant conditional correlation, dynamic conditional correlation, VARMA-GARCH and VARMA-AGARCH models. So this paper presents interdependences in...

return and volatility spillovers are important for portfolio selection, asset valuation and market efficiency investigation. using a var-bekk framework model, this paper investigates return and volatility spillover effects between three size-sorted equity indices in tehran stock exchange (tse). although daily return of large stocks leads small stocks (lead-lag effect), there wasn’t any spillove...

crop rotation affect on crop nitrogen uptake and nitrogen use efficiency (nue). crop rotations with high nue decrease energy use and increase level of sustainability in agro ecosystems. the objectives of this research were to determine the suitable double cropping system for enhancing nue and evaluate the effects of crop rotation, n fertilizer rate and return of crop residue on nue. this study ...