A numerical model is implemented to describe fluid dynamic processes associated with mid-latitude small-scale (10 km) upper OCEAN fronts by using modified state of the art computational fluid dynamics tools. A periodic system was simulated using three different turbulent closures: 1) URANSReynolds Stress Model (RSM, seven equation turbulence model), 2) LES-Standard Smagorinsky (SS, algebraic model), and 3) LES-Modified Smagorinsky, introducing a correction for non-isotropic grids (MS). The results show the front developing instabilities and generating sub-mesoscale structures after four days of simulation. A strongly unstable shear flow is found to be confined within the mixed layer with a high Rossby number(R0>1) and high VERTICAL velocity zones. The positive (negative) VERTICAL velocity magnitude is found to be approximately O (10-3) m/s (O (10-2) m/s), one (two) order (s) of magnitude larger than the VERTICAL velocity outside the sub-mesoscale structures, where the magnitude is stable at O (10-4) m/s. The latter value is consistent with previous numerical and experimental studies that use coarser grid sizes and therefore do not explicitly calculate the small scale structures. The nonlinear flow introduced by the sub-mesoscale dynamics within the mixed layer and the non-isotropic grid used in the calculations generates a disparity between the predicted horizontal wave-number spectra computed using the RSM model with respect to the linear eddy viscosity model SS. The MS approach improves SS predictions. This improvement is more significant below the mixed layer in the absence of flow nonlinearities. The horizontal spectra predicted with the RSM model fits a slope of -3 for large scale structures and a slope between -2 and -5=3 for turbulent structures smaller than 300 m. This work contributes to the investigation of the physical and methodological aspects for the detailed modelling and understanding of small scale structures in OCEAN turbulence.

This paper describes the observation and analysis of VERTICAL electron density before major earthquake above the Sumatra-Malaysia region during Indian OCEAN major earthquake in 2004 in Aceh, Sumatra. The electron density profile in E-layer of ionosphere a few days before earthquake and a few hours after earthquake have been observed using the data from the CHAMP satellite. The data obtained from the CHAMP satellite based on GPS radio occultation technique, starting from 21st Dec, 2004 until 27th Dec, 2004, between 90 - 120 km altitude ranges. It is shown that significant anomaly can be detected as early as 3 days before the major earthquake above the preparation zone of earthquake epicentre through significant disturbances of the electron concentration in the ionosphere. In addition, the electron density in the ionosphere above the earthquake epicentre is observed to be very high during 8 hours before earthquake occurred. After a day of the earthquake occurrence, it is observed that the electron density decreases and the ionospheric region become more stable.

MIXING of heated water discharged from outfalls is an efficient and effective method of waste disposal in coastal areas. Discharging the heated water with large quantities of mass flux generally requires multi-port diffusers. In recent years, using numerical models to predict the plume behavior has received attention from many researchers, who are interested in design of outfalls. This study reports the development and application of an artificial neural network model for prediction of initial dilution of multi-port tee diffusers. Several networks with different structures were trained and tested using error back propagation algorithm. Statistical error measures showed that a three layer network with 9 neurons in the hidden layer is skillful in prediction of initial dilution and the outputs are in good agreement (R = 0.97) with experimental results. Furthermore, the sensitivity analyses showed that the width of the equivalent slot of the diffuser is the most important parameter in the estimation of initial dilution.

Statement of Problem: Total removal of tissues and remnant microorganisms as well as canal shaping is the essential objectives of endodontic therapy. A successful endodontic treatment is obtained through Shilders principals, however; complete observation of this technique using stainless steel files manually is problematic and time-consuming. Modern technology, in order to eliminate such problems, has presented new facilities such as Nickel-Titanium (NiTi) files and engine driven instruments.Purpose: The aim of this in-vitro study was to compare the canal debridement efficiency of three engine driven instruments: Rotary, Reciprocal and VERTICAL.Materials and Methods: In this experimental study, 60 mesial roots of human first and second mandibular molars were divided into three groups randomly. In each sample, one canal was considered as case, the other one as control. Files used in Reciprocal and VERTICAL groups were of handy Ni-Ti type and in rotary group, rotary Ni-Ti files were used. After debridement, the roots were sectioned at 3mm and 5mm from anatomic apex, stained and examined under light microscope. Comparison criteria between case and control groups were based on residual debris and predentin and the level of root canal preparation and shaping after debridement. Data were subjected to kruskal-Wallis non-parametric test.Results: There was no significant difference between the efficiency of debridement at 3mm and 5mm sections between all groups. But difference in time consumption was significant ranked from the shortest to the longest as rotary, reciprocal and VERTICAL.Conclusion: The efficiency of debridement between the three automated instruments was approximately equal, however; the instrumentation time was different between three groups. Rotary system was the fastest one, as compared with reciprocal (second) and VERTICAL (last). It may be concluded that rotary system has a superiority over the other two groups in conventional root canal therapies.

The interplay between stratification and shear in lakes controls the VERTICAL MIXING, which is the most important mechanism affecting the transport of heat, salt, momentum and suspended and dissolved substances. This study attempts to quantify and characterize the turbulence from direct measurements conducted in a reservoir. A 3D numerical model is used to investigate the water column hydrodynamics for the duration of measurements and the performance of various turbulence models used in the CFD model are investigated via simulation of MIXING in the reservoir. The drawdown curves produced by the turbulence models are formulized through linear equations. Although, use of different turbulence models do not have significant effects on the flow hydrodynamics away from the intake structure, significant effects especially on turbulence kinetic energy production are observed at the orifice. Therefore, for simulation of withdrawal flow, either use of shear stress transport (SST) k-omega models solving equations all the way to the wall or kepsilon models with the nonequilibrium wall function is recommended to account for the changes in the pressure gradient. In this study, the methods using quantified turbulent characteristics of the flow to reformulate the Stokes’ settling velocity to be applied in turbulent flows are also investigated. An approach to predict setting velocity in turbulent flows that utilizes acoustic Doppler instruments for quantification of turbulent characteristics is presented. Modification of the Stokes’ settling velocity with the nondimensionalized turbulent kinetic energy production profiles lead better results than other turbulence characteristics (buoyancy flux and by Richardson number flux) widely used in characterizing turbulent MIXING.

Tropical cyclones develop over the north and south part of Indian OCEAN because of the geographical and weather conditions. It causes irreparable damage to human life and economy on coastal areas. This study investigates the energy of OCEAN surface waves generated by the surface wind field of tropical cyclones in the Indian OCEAN using satellite altimeter measurements and the semi-empirical Kudryavtsev model by considering “ trapped fetch” . The translational velocity and information of tropical cyclones were obtained from the Joint Typhoon Warning Center (JTWC) best-track data and Jason 1 and Jason 2 satellites data set for 18 tropical cyclones between 2003 and2013. The results of this study indicate that the semi-empirical model suggested by Kudryavtsev in 2015 can be used to investigate and simulate unusual waves generated by tropical cyclones in the Indian OCEAN.

The upcoming study investigates the design and use of VERTICAL-axis wind turbines for power extraction in Chahnimeha, Zabol. In Sistan and Baluchestan provinces, due to the vastness and climatic barriers, the use of renewable energy can greatly contribute to the well-being of people. Using the meteorological data of this province, the average wind speed in the Chahnime region is estimated at 6.4 m/s. At first, 4 airfoils with the highest lift-to-drag coefficient have been selected and studied for wind turbine design. By choosing the best airfoil among the four examined ones, a wind turbine with 3 different blade sizes and rotor radius was designed. The wind turbine, which is designed with a blade length of 3 meters and a rotor radius of 1.5 m, has the best performance. The VERTICAL axis wind turbine has been investigated in 4 models with 3, 5, 7, and 9 blades. The power factor of the 3-bladed turbine is equal to 0.30, and of the 7-bladed wind turbine is equal to 0.45. Among the examined wind turbines, the best wind turbine with 7 blades was chosen. The reduction of wind speed before the blades is influenced by the solidity of the wind turbine. The study of wind turbine exergy was used to investigate the environmental effects such as humidity and temperature on the performance of wind turbines in the climatic region of Zabol. The exergy efficiency of the designed 3-blade and 7-blade wind turbine is equal to 45 and 75%, which shows the effect of temperature and relative humidity on the wind turbine efficiency in a climate region. The results of this study clearly show that it is possible to use a 7-blade VERTICAL axis wind turbine to provide electricity to areas far from the grid and to produce scattered.