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The aim of this study is to investigate different risks of e-banking in private and public banks of Iran. Despite the certain benefits, e-banking carries tremendous risks. The major risks that are associated with e-banking are strategic, operational, legal and reputational risks. Security is considered the central operational risk of e-banking. For example; breach of security allowing unauthorized access to customer information can be classified as an operational risk, but it also exposes the bank to legal and reputational risks. The methodology used for this study is Questionnaire (AHP), and statistical software for data collection and analysis. Senior managers and vice-chancellor of private and public banks are the research population. Finally, based on the research findings, a few suggestions will be offered for electronic banks' risk management in public and private banks.   Keywords: Electronic Banking, Strategic Risk, Operational Risk, Reputational Risk, Legal Risk

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Inverse design is one of the design methods of aerodynamic ducts such as S-duct intakes. In these problems, the geometry of the duct is unknown but the pressure distributions along the walls are given. In this paper, a new inverse design method called “flexible string method” is introduced. In this method, the duct walls are modified from initial guess to final shape based on the flexible string movement algorithm according to pressure distribution. In 3D design, the duct design process starts with a 2D one. At first step, a 2D Jet-Engine S-shaped air intake considering flight mach number is designed using the inverse design method based on an Euler flow solver (with no considering the jet nose engine effects). At the second step with considering duct sections like circle, ellipse and bean the 2D duct is modified to obtain the 3D duct. Finally, it is validated by analyzing the duct flow in 3D turbulent regime. The numerical studies show in spite of severe height change with respect to duct length, there is no separation in the duct and the uniformity of flow at the duct exit is completely satisfactory.

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Oil and gas processing activities is causes excess water consumption, which leads to excessive production of wastewater. This produced waste water contains mineral and biological compounds which can contaminate water and ground water. Vast amount of this industries’ produced wastewater in Oil-rich countries which mostly are arid countries, lead them to find more effective methods for water reuse as a new water resources. One of the most important water pollutant are heavy metals, so investigator are believe that heavy metals toxicity into environment is more than which disperse from radioactive toxicity to ground water and seas. Various physical, chemical and biological methods of waste water treatment are applied in refining and petrochemical industries. considerable amount af mercury with different operational units’ wastewater is discharge to environment from refinery units. Since mercury is not biodegradable and tend to accumulate in living organisms, we must be able to control it by using effective methods. Application of membrane filtration is new method for water and wastewater treatment industry. In this research, by application of case study on one of the nation’s gas refineries, reverse osmosis membrane system performance under different operating conditions, was studied. For this purpose effects of variable parameters, namely operating pressure (5, 7, 9 and 11 bar), pH (3, 6, 9, 11) and mercury concentration (1, 2, 4, 8 and 12 mg/l) on removal performance were studied. Considering removal performance of mercury, COD, TDS, EC, Turbidity and also membrane flow rate, optimum operating condition was obtained. Base on the results, reverse osmosis membrane performance is efficient in optimum parameters’ value, namely 7 bar pressure and pH=9 from permeate water quality and economical aspects. by increasing system pressure a significant decline in mercury and COD removal efficiency was observed. removal efficiency of mercury, COD, and TDS in 7 bar pressure condition was 91.35%, 99.55%, and 94.89% respectively and also permeat flowrate was acceptable, so 7 bar was found as optimum pressure. On the next stage af investigation, although by increasing wastewater sampel’s pH, a considerable increase in mercury and COD removal efficiency was observed, it cause a dramatic rise in TDS and turbidity in feed wastewater and also in permeate stream. More over high value of pH, namely pH=11 can make system prone to fouling. So pH=9 was choosen as a optimum pH. Finally reverse osmosis membrane performance in encountering with possible shocks and high concentration of influent mercury was investigated. Although results shows a significant decrease in membrane removal efficiency in encountering with high influent mercury concentration, reverse osmosis membrane system efficiency in mercury removal is acceptable in encountering conventional mercury concentration of refineries. reverse osmosis membrane performance is efficient in optimum parameters’ value namely 7 bar pressure and pH=9, so removal efficiency of mercury,COD, and TDS was 97.5%, 99.755 and 93.29% respectively.

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Derivation of temperature distribution, at the different sections of nose, to select the material, component, and sensitive system installation at inside of it, implicates to specifying the induced aeroheating to the nose surface. This parameter with surface temperature and recess due to surface ablation must be corrected at next time steps of flight trajectory. The different methods, to estimate or calculation of aeroheating, were created whereas the most accurate method for this purpose is numerical solution of fully navier stocks, chemical dissociation and ionization of air, mass conservation of species, turbulence modeling, combustion modeling due to surface ablation, nose heat transfer equations with time marching finite volume algorithms simultaneously. Utilizing these solvers for flight trajectory is snail, and it’s required the high computational memory. Therefore, the finite difference method is used, and the governing equations are translated to curvature coordinate by mapping terms. By using this translation, to solve the governing equations, the space marching solvers can be used. Therefore, in this research, the more accurate estimation of temperature distribution for 3-D nose of supersonic and hypersonic vehicles was presented by using the numerical space marching solvers such as viscous shock layers and viscous boundary layer methods. Therefore, the comprehensive code was created to this purpose. The results of this code were validated by using the temperature telemetry results of flight tests. The relative error of the results was less than 10 percent.

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The main objective of this study is investigating the relevance of momentum and liquidity market status on short-term (6 and 12 months), medium-term (24 months) and long-term (60 months) periods. Statistical sample in clouded 270 firms that were accepted during years 82-85 in Tehran Stock Exchange, and are still working. The results showed that liquidity market status is a factor for separation of the market's effects on excess returns in different  periods of times. So that the momentum in the companies with high liquidity in 6 months formation and 6 & 12 months holding periods was positive, and the momentum in the companies with low liquidity in 24 & 60  months holding periods was negative. Also there was no significant difference between the profitability of momentum strategy in the companies with high and low liquidity.      

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Using proper dimensionless coefficients that are insensitive to various operating conditions is a crucial issue during the utilization of a yawmeter probe. These dimensionless coefficients produce the deviation angle of flow, stagnation and static pressures. In the current study, these coefficients are analyzed using SPM analytical and experimental methods. A comparison of experimental and analytical results shows that SPM analytical method predicts the flow deviation coefficients satisfactorily at the operational angle range of three-hole probe. This method also calculates the stagnation pressure coefficient precisely at the deviation angle range of ±10 degrees. The experimental results show that due to the assumption of constant speed on the probe, the analytical method cannot calculate the static pressure accurately. Experimental observations also demonstrate that velocity is increased and pressure is decreased over the probe. This is due to the suction region at the downstream of probe. Unlike analytical results, experimental observations depict that at zero degrees, the flow static pressure is equal to the average of pressure at the left and the right side of probe. Due to sensitivity of dimensionless coefficients of flow static pressure to variation of Reynolds number, various values are reported at different kinds of literature for these coefficients. These coefficients change with Reynolds number variations and their accuracies are decreased. In the current study, a new proper dimensionless coefficient is introduced which represents minimum sensitivity to Reynolds number.

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