Objective: Modelling Dynamic nature of covariance of assets return almost always is a challenging area of finance. Econometrics models just pay attention to variance behavior longitudinally, however, core of numerous finance models need the analysis of the total covariance structure of returns. Method: Among the first models that analyze covariance behavior are multivariate GARCH models which were criticized for the need to estimate a large number of parameters. This paper is aimed to investigate the effect of stock return Dynamic Correlation structure on systematic risk, idiosyncratic risk and average stock return. To this end, a sample of 148 listed companies in Tehran Stock Exchange is examined during 2003 to 2014. GARCH framework is used for testing this claim. Results: According to the results, securities that were highly correlated with market wide risk factors in the past are likely to have low systematic risk, idiosyncratic risk and average return at present. It can be expected there is significant relationship between idiosyncrstic risk and Correlation for lower turnover stock (information transparency proxy) although there is no relationship for smaller firms.

Due to the lack of measurements in many regions, wave characteristics are estimated using different methods. Wave climate hindcasting/forecasting is mostly conducted by numerical models or empirical methods. Until now, different empirical methods have been developed for wave hindcasting. However, with the development of high speed processors, several sophisticated numerical models have been developed for wave prediction. These models are mostly phase-averaged spectral wave models developed in three generations. In the last two decades, third generation wave models have been used widely in academic and practical projects. In this regard, Port and Maritime Organization has produced his own model, PMO Dynamic. This model has been developed as a part of first three phases of Monitoring and Modeling of Study of Iranian Coasts project. PMO Dynamic package is a software available for engineering purposes. It has several modules that have been developed for different objectives. Wave model is the module which is used for the generation and transformation of wind waves in coastal areas. In this paper, in order to test the PMO Dynamic model capabilities, it has been applied for the prediction of wave parameters in Bushehr Bay and the results have been compared with MIKE21 SW model and measured data.

The housing sector and capital market are known as the main investment options in each country that they have been recently taken into consideration as a focal point for legislative institutions and economic policy makers (particularly, since the start of financial crisis). This paper examines Dynamic conditional Correlation and volatility transmission between the housing sector and capital market from 2005 to 2016 through using four Multivariate GARCH Models. The survey revealed the volatility transmission between the housing sector and capital market on various levels. Also, results of the study imply a positive cross-sectional Correlation between two markets in the long run in spite of negative impacts of housing sector shocks on the capital market in the short run. The issue can be played a major role in explaining the exact movement between two markets with a view to understanding investment flows in Iranian society as well as considering systemic dimensions of volatility in the housing sector. This article offers to establish a financial stability and development committee (on financial-mortgage products) to oversee a severe and escalating financial crisis as well as assist with de-escalating a situation.

Background: In intertrochanteric fractures، Dynamic hip screw (DHS) is the most frequently used tool، but several studies did not give good results for this device in reverse-oblique and transverse fractures. Current study aimed to compare fixation results of reverse-oblique intertrochanteric and short-segment subtrochanteric fractures using Dynamic condylar screw (DCS) and DHS in patients referred to Alzahra and Kashani Hospitals in Isfahan, Iran.Methods: In a cross-sectional study، medical files of the patients referred to emergency units of the two hospitals who were diagnosed with intertrochanteric or subtrochanteric fractures and underwent DHS or DCS surgery more than 6 months before were assessed; they were invited for follow-up visit and examination. Written consent forms were taken from all the patients upon their entry; and they were examined in terms of complications including nonunion and failure of device and level of fracture improvement. These cases were evaluated by simple radiography ,too. Results obtained from examination of patients in addition to demographic information were recorded in the data collection form for each patient.Findings: Perfect union was observed in 14 (of 25) patients in DHS group and 21 (of 25) patients in DCS group (56% vs. 84%) six months after the surgery. Bone union was significantly better in DCS group (P=0.031). In addition, six months after the surgery, the devices used in 14 people in DHS group and 24 people in DCS group were fixed and the difference between the two groups was significant (P=0.001). 14 and 24 patients had total recovery in DHS and DCS groups، respectively (20% vs. 44%) with a significant difference (P=0.020).Conclusion: Considering obtained results, it can be concluded that using DCS is recommended over DHS due to severity of pain, bone union and fixation of the device.

This study investigates the time-varying Correlations among oil and coin prices, and exchange rate in Iran. Since investment is a key factor in economic growth and development, so the necessary funds should be provided and directed towards manufacturing and industrial sectors. In addition, understanding the relationships among financial variables allows to the investor to reduce overall portfolio risk without harming to the return on investment. In this paper we use monthly data of the oil and coin prices, and exchange rate in Iran over the period 1991: 3 to 2011: 2 and examine time-varying Correlations using Dynamic Conditional Correlation - Generalized Autoregressive Conditional Heteroskedasticity (DCC-GARCH) approach by G@RCH6 software. The analyses made in milieu of the world financial crisis (2008) show that the conditional Correlations among assets are time-varying and world financial crisis causes significant changes in Dynamic relationships among assets under study in Iran.