Investigation of the sliding, overturning and stress analysis and crack propagation of GRAVITY dams based on hydrostatic pressures and earthquake forces are of importance. In this research the CADAM2000 software was used for the of stability analysis GRAVITY concrete dams. This program models the pseudo-static and pseudo-dynamic earthquakes based on CHOPRA (1988) method. The Chopra crack propagation along the joints was calculated by considering the boundary conditions (initial cracks). The sliding, overturning, uplift stability factor and allowable stresses were calculated using the data collected for the Pine Flat GRAVITY concrete dam as case study for this research.

Since 1954 there have been 5 censuses in Iran.The 18.9 millions population of Iran in 1954, reached more than 60 millions in 1994, which is more than three times. During this period, the urban population raised from 6 millions in 1954, up to 36 millions in 1994, which is more than six times. At the same time, the rural population grew from 13 millions to 23 millions, which is less than double.Statistics shows a high rate of population growth and an immense migration from rural areas to urban areas and cities, in this period, in Iran.The main purpose of this paper is to trace the directional changes of the urban population GRAVITY centers in the last half century. The calculations show that the urban population GRAVITY center moves from NE to SW, while these GRAVITY centers are located around Ahvaz city in Khouzistan province.Based on past trends and recent economic developments the future GRAVITY center will continue to move towards SW, but more inclined to south rather than west.

Introduction: Many of unique phenomenons in atmosphere and ocean are deduced by air-sea interaction that one of them is GRAVITY currents that are occurred in the semi-closed marine environment. These currents as a component of sea waters circulation have effective role on some of the marine activities such as military, communications, fishing, researching and ….Aim: The aim of this paper is: - survey of presence of the outflow GRAVITY currents from Persian Gulf as the component of sea waters circulation- survey of some of characteristics of these currents in Persian Gulf Material and Method: Presence of the outflow GRAVITY currents from Persian Gulf is surveyed by comparison of water salinity and density profile of Persian Gulf with another seas such as Spencer Gulf that Presence of these currents are confirmed by measurements in there. Also, some of characteristics of the outflow GRAVITY currents from Persian Gulf such as velocity, direction and … are determined by solving motion equations under ageostrophic steady condition by dynamical geometrical method of forces projection and using diagrams resulting of collected data by Mount Mitchell ship cruise in February – June 1992 corresponding to ROPME project.Results: This study shows that outflow GRAVITY current from Persian Gulf is a permanent current that amplifies in during February – June and peaks on March.Conclusion: This current with the thickness about 35m, mean velocity about 0.4 m/sec and friction coefficient of order0.783 × 10−3 slips down the slope at an angle of about 7.84o to the isobaths.

In this paper, the applicability of Euler's homogenous equation method in detecting GRAVITY anomalies from GRAVITY or microGRAVITY data is addressed. The stability of Euler solutions with respect to the window size, window position and choice of the structural index value (defining the anomaly attenuation rate) is analyzed and demonstrated using synthetic microGRAVITY data created for different anomaly models. The analysis reveals that the optimum window size required to obtain the best solutions is a function of the source depth. The horizontal location parameters can be determined correctly if the window is located in the region of high derivatives regardless the assigned structural index v. Meanwhile, depth solution is linearly dependent on the structural index and incorrect choice of structural index leads to significant error in the estimated depth.

GRAVITY anomalies always include the total effects (combination of the structures which have different densities and depths) of the study area and beyond.The regional-residual resolution of the potential field continues to be a topic of considerable interest among geophycists even to a present time. In spite of a large number of sophisticated analytical techniques both in the space and frequency domain, there are instances where interpreters are not satisfied with the regional and residual components obtained by this method.The finite element method (FEM), which has been used in potential field interpretation for decades, makes complex problems to be solved easily and accurately.A regional GRAVITY anomaly, based on element shape functions used in finite element analysis, is developed. The first step of FEM is to identify the elements and then to decide onthe boundary of the solution space, the solution space is divided into elements. After determination of the geometrical structure of the solution space, the most suitable elements should be chosen for this geometrical structure. The agreement between the geometry and the elements is quite important for the convergence to the best possible solution.In this work FEM was applied to a theoretical model and to GRAVITY data from salt dome structure in Qom to produce the regional and residual anomalies.

Geophysical methods are used as locating tools and reconnaissance methods. GRAVITY method is used to locate underground structures and cavities using density contrast. In this paper, methods of airborne gravimetry and airborne GRAVITY, gradiometry, corrections and their modern instruments have been presented. In order to evaluate the accuracy and efficiency of these methods, a developed program have been used. Artificial data of an underground structure have been provided by forward modeling for earth surface at different altitudes and then noise were added to data. Finally the results of the simulation and the accuracy of the presented instruments for different altitudes have been compared. In conclusion effective solutions to mitigate the probable detection of buried structures and the improvement of camouflage processes against airborne reconnaissance are provided.

A number of forced GRAVITY drainage experiments have been conducted using a wide range of the physical and operational parameters, where the type, length and permeability of the porous medium as well as oil viscosity and injection rate were varied. Results indicate that an increase in Bond number has a positive effect on oil recovery whereas capillary number has an opposite effect. Furthermore, it was found that use of each number alone is insufficient to obtain a satisfactory correlation with recovery. A combined dimensionless group is proposed that combines the effect of all three forces. The exponent of the Bond number in the proposed group is larger than the capillary number suggesting a larger importance for the former. We then show that the same group provides a good correlation for recovery from addition experiments conducted in this work and another set of experiments in the literature.

Summary: One of the most important problems in the interpretation of GRAVITY or magnetic data is to obtain information about the sources position (geometry and depth). Potential field automatic interpretation techniques can significantly decrease the interpretation workload of a geophysicist and are widely used. Automatic interpretation methods can be classified into two major groups: modeling and analytical. Euler Deconvolution, Werenr Deconvolution and recently, Tilt-Depth method are the commonly used (practical goals) analytical methods. The basic idea in Tilt-Depth method is simultaneous application of tilt angle for edge and depth estimation of magnetic contact model. In this method, the vertical and horizontal gradients of magnetic contact substituted in tilt equation lead to an equation for depth estimation. This paper generalizes the tilt-depth method to GRAVITY data using the horizontal cylinder and the buried sphere models.Introduction: Salem et al, (2007) introduced the tilt-depth method for the magnetic anomaly over a contact. Previously Miller and Singh had developed the tilt angle as a method of enhancing images of the vertical derivative of potential field data. The tilt-depth method only depends on mapping specific contours of the magnetic tilt angles. The zero contours delineate the spatial location of the magnetic source edges whilst the depth to the source is the distance between the zero and either the –45° or the +45° contour or their average. The tilt-depth method adds to the arsenal of geophysical methods currently in use to estimate magnetic source depths, many of which use second- and/or third-order derivatives. These include methods based on Euler’s equation and the local wavenumber, both of which calculate the source depths for a range of source-body geometries, and, more recently, for the simultaneous estimation of both source depth and source type. Methodology and Approaches: In this paper, the tilt-depth method will be both generalized (by applying it to GRAVITY models) and extended (by using all values of the ratio of the field gradients, not just a single value). The GRAVITY models used are 2D horizontal cylinder and buried sphere. In this regard we developed a MATLAB code for applying the proposed method to synthetic and real data. In this code the selection of the ratio of the vertical to horizontal derivatives are done on the basis of the signal to noise ratio of the dataset. Also for the consistency of result the vertical derivative is calculated using Hilbert transform. The final equation was solved by Newton method. Results and Conclusions: The efficiency of the proposed method tested using various synthetic GRAVITY models. The sensitivity of methods to noise and interface was tested using synthetic data. On the basis of observations the method is sensitive to noise, but if the data continued upward before applying the algorithm or using of the stable derivative operator the inconsistency of the result decreases seriously. For overcome in body overlapping phenomena we suggest anomaly windowing or insulating by means of Bott (1966) algorithm. This method applied on 2 GRAVITY profiles from Shavaz Iron ore in Yazd province. Then the results compared with power spectrum depth analysis. Accordance to this comparison the proposed method could produce the same result as power spectrum. In this case w upward GRAVITY data to 2m in order to decrease noise content.

Introduction: Polyuria and nocturia may be the first clinical manifestation of hyperthyroidism. Most of the reported studies about renal function in Hyperthyroidism are performed in animals.Material and Methods: In this study we have evaluated 12-hour urine volume and specific GRAVITY of morning urine in 50 new hyperthyroid patients and we have compared the results with similar study in 34 normal persons from their families in the same age group (control).Results: We found significant increase in urine volume (p<0.001) and decrease in specific GRAVITY in patients with hyperthyroidism (p<0.001). There was no significant correlation between urine volume and specific GRAVITY with plasma concentration of thyroid hormonesConclusion: There is increased urine volume and decreased specific GRAVITY. This should be considered in differential diagnosis of diabetes insidious.

Introduction: In most cases after periodontal surgery, the surgical area is covered with surgical packs. Recent studies suggest that use of periodontal packs after periodontal flap surgery is not necessary and some patients may be irritated by them. The aim of this study was to determine microbiological contamination of a periodontal pack (Coe-pak) by determining microbial colony counts of surgical sutures after MODIFIED Widman flap surgery.Materials and Methods: In this clinical trial, thirty-two patients needing periodontal surgeries at least in two quadrants of jaws were selected. In one quadrant, after surgery the surgical area was covered with periodontal pack randomly and the other quadrant was left without any dressing. After a week the sutures were removed and microbiological colony counts were determined. Finally microbial colony counts in the two groups were compared between the two groups by paired sample test using SPSS software (a=0.05).Results: The mean colony counts with and without periodontal pack were 10187±2900 and 9812±3042, respectively, with no statistically significant differences between the two groups (p value=0.602).Conclusion: The results of this research showed that sutures have microbial contamination with or without use of periodontal packs and these materials have no effect on microbial contamination.