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The seismographic data, as well as historical resources are indicative of the occurrence of numerous earthquakes in the region of Garmsar since the prehistoric centuries. The 4th century BC earthquake in the region of Caspian Gate and Eivankey City with the magnitude of Ms = 7.9 and intensity of Io = X and also the earthquake of spring 743 AD, (Spring 122 Hegira, Solar year)estimated at the magnitude of Ms= 7.2 and intensity of Io = VIII in the region of Sardarreh Khar (Caspian Gate) and Takhte-Rostam Mountain, and earthquakes of Moharram 1367(3th of September, 1988) continuing for one year, inspired the author to investigate and introduce the causing factors of these earthquakes. In this research, it has been identified that on one hand factors such as activation of certain unknown faults.The geographical distribution of the seismological focus properly indicate Garmsar,s fault activation and the faults of Rude-Shur valley, Ejdeha Mountain and the faults of north and south part of Kalarz Mountain and Red Mountain, Rameh, Ghalibaf, Gach-ab and Gugerd Mountain faults have been acted in the past history of this region (Fig. 2).

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Learning rapidly and competently has become a pre-eminent strategy for improving organizational performance in the

new knowledge era. Improving dynamic learning capability is an exclusive strategy for corporate success in construction

industry. Thus engineering design firms should implement OL to accomplish a state of readiness for change and develop a

competence to respond and identify future business potentials. This study aims to analyze the relationship between

organizational learning (OL) and performance improvement (PI) in civil engineering design firms of Turkish construction

industry. OL structure in engineering design firms incorporates five constructs: organizational environment, strategy

development and implementation, supportive leadership, leveraging knowledge, and learning capability. The empirical data

was collected through a questionnaire survey conducted to engineering design firms registered to the Turkish Chamber of Civil

Engineers. The hypothesized model relationships were tested using Structural Equation Modeling (SEM). The results show that

each of the variables has a different role and significant positive impact on the OL process and organizational PI. The variables

“Supportive leadership” and “Learning capability” proved to be strongly significant and positively related to organizational

performance in engineering design firms. In engineering design firms, supportive leadership is needed in order to establish a

participative cultural environment that helps design a new form of organization which emphasizes learning, flexibility, and

rapid response. Learning capability is the potential to explore and exploit knowledge through learning flows that make possible

the development, evolution and use of knowledge stocks enacting engineering design firms and their members to add value to

the design business.

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The objective of this work is to perform a direct numerical simulation of turbulent channel flow where all essential scales of

motion are resolved due to variable time-stepping algorithm in various time advancement method and different discritized form

of convection term. A pseudo spectral method (Fourier series in stream-wise and span-wise directions and Chebychev polynomial

expansion in normal direction) is employed for the spatial derivatives. The time advancement is carried out by different semiimplicit

and splitting schemes. Also Alternating and Linearized forms are added to four commonly used forms of the convective

term, referred to as divergence, Convection, skew-symmetric, and rotational. Spectral method based on the primitive variable

formulation is used in Cartesian coordinates with two periodic and one non-periodic boundary condition in three dimensional

directions &Omega=[0,4&pi]×[-1,1]×[0,2&pi]. The friction Reynolds number for channel flow is set to be Re&tau=175 and the computational

grids of 128×65×128 are used in the x, y and z directions, respectively. The comparison is made between turbulent quantities

such as the turbulent statistics, wall shear velocity, standard deviation of u and total normalized energy of instantaneous velocities

in different time-discretization methods and different forms of nonlinear term. The present results show that third-order timediscretizations

forward Euler for explicit terms and backward Euler for implicit terms can minimize the computational cost of

integration by maximizing the time step, while keeping the CFL number near a threshold in time-discretization schemes. Also, the

de-aliased results of turbulence statistics do indicate that different expressions of nonlinear terms have minor discrepancy in

pseudo spectral method. The results show that the most desirable approach is a combination of variable time stepping third order

backward difference algorithm and rotational form, which provides reduced cost and further accuracy improvements.

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The occurrence of wave and wind forces on tension leg platform (TLP) was assumed to be statistically independent but the intensity of wave force is a function of wind velocity because wave is a wind driven force. The focus of this paper is to study the effects of wind velocity on wave force. The contribution of steady and fluctuating wind to the response of the TLP over random wave only was also studied. Pierson Moskowitz wave and Emil Simiu wind spectra are simulated using Monte Carlo simulation. The variable submergence, drag force in Morison equation, tension fluctuation together with coupling between wind and wave contributed to the non-linearity considered in the single degree of freedom equation. The dynamic equation was solved using Newmark-Beta scheme. The statistical and power spectral density functions of the response quantities are reported. It is concluded that wind forces reduce the root mean square (RMS) tension force in the cable and thereby increased the motion responses in intact and a removed tendon TLP. The wind driven force (wave) has higher responses in severe sea states and the contribution of wind effect was suppressed due to hydrodynamic damping. The effect of the wind fluctuation is more pronounced in less severe sea state.Stochastic response of intact and a removed tendon tension leg platform to wave and wind loads

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Construction industries are the most dangerous worksites with high risk of occupational accident and bodily injuries, which ranges from mild to very severe cases. The aim of this study was to explore the causal factors of accident severity rate (ASR), in 13 of the biggest Iranian construction industries. In this analytical cross-sectional study, the data of registered accidents from 2009 until 2013 were obtained from an official database. Data of HSE risk management systems and HSE training were also gathered from comprehensive accident investigation reports. Data analysis and regression modeling were done using SPSS statistical software (version 22). The mean and SD of ASR of studied construction worksites was 257.52±1098.95. The results show that the system associated with HSE and HSE risk management established only 41.8 and 18.4%, respectively. The results of multiple linear regression indicated that some individual and organizational factors (IOFs), HSE training factors (HTFs), and Risk Management System factors (RMSFs) were significantly associated with ASR (p<0.05). The study revealed the causal factors of ASR. Hence, these findings can be applied in the design and implementation of a comprehensive HSE risk management system to reduce ASR.