2Background and Aims: GUIDED endodontics is a new technique that is now evolving. It is used in many treatments, especially in access cavity preparation and locating root canals in teeth with pulp canal obliteration (PCO), microsurgical endodontics, and fiber post removal in retreatments. In addition, this technique is independent of operator experience, requires less treatment time for the patient, and is more precise and safer than conventional endodontics. This technique involves the use of cone beam computed tomography imaging (CBCT), tooth surface scanning, and special software to provide guidance for performing endodontic treatment in a fast, safe, and minimally invasive manner. This review article aims to introduce GUIDED endodontics and to describe its technique, advantages, and limitations.

Background: Fine Needle Aspiration (FNA) has commonly been employed as a relatively non-invasive and reliable diagnostic modality, however, In Iran we lack adequate experiences. Materials and methods: In this retrospective study, 240 cases of CT GUIDED FNA have been reviewed.Results: Of 240 cases, 225 FNAs (94%) had adequate specimens. Most cases had clinical diagnosis of malignancy. 100 cases were cytologically confirmed to have malignancies. Of these 100 patients, 82 also had needle biopsy, of whom 73 biopsies provide adequate specimens (90%). Of these 73 biopsies, 68 (93%) were histologicaly confirmed to have malignancies. Conclusion: To reduce the complications of invasive methods, we highly recommend CT GUIDED FNA.

This paper deals with the design of a deformable nose for the non-penetrating PROJECTILE in order to prevent its body deformation. Numerical, analytical and experimental studies have been carried out to analyze the effect of different nose shapes on the PROJECTILE deformation when it hits the brick wall. The PROJECTILE consists of an aluminum nose, a thin-walled steel cylinder body, and an end connector. This non-penetrating PROJECTILE can be used to carry a cargo that must reach its destination safely, for example in firefighting applications. To pursue this goal, the criterion utilized for the best design in this paper is stress and strain analysis. The geometric shape of the noses includes three types: type (a), type (b), and type (c). The first type of nose was flat shape. This nose was detached from the PROJECTILE by impact and did not prevent the PROJECTILE deformation. The second type of nose was a combination of flat and conical shapes. The PROJECTILE was also deformed by this nose. The third type of nose was a combination of flat, conical, and spherical shapes. Due to the maximum absorption of the impact energy, this type of nose prevented the deformation of the cargo and PROJECTILE.

Circular saws and angle grinders are two of the most dangerous pieces of electrical equipment on a worksite. Besides the danger that any high‑ powered, sharp piece of equipment possesses, these pieces use circular saw blades that can splinter into PROJECTILE fragments. A 60‑ year‑ old male was cutting a steel pipe with a circular saw when a fragment of the 12‑ inch blade flew off, impaling him in the upper face just to the right of the midline. He was wearing eyeglasses, the bridge of which was driven into his skull on impact of the fragment. He was brought to the trauma center where he underwent imaging of his face and head. This revealed that the blade and his glasses had penetrated 1. 2 cm into the right frontal lobe of the brain, resulting in facial fractures and intraparenchymal hemorrhage. He underwent bifrontal craniotomy, removal of the blade and his glasses, evacuation of hematoma, and dural reconstruction. Postoperatively, he was awake with a Glasgow Coma Scale of 15 and no neurologic deficits. The complex nature of craniofacial injuries makes a multidisciplinary approach to these patients essential. Prompt diagnosis and treatment by the appropriate specialists are vital to optimize patient outcomes.

In this paper, a sliding mode guidance (SMG) law for a smart PROJECTILE with its optimization is presented. Due to the importance of acceleration of maneuvering targets due to their complex and inaccessible nature, an estimated upper bound of the target acceleration is considered as a disturbance in the formulation of the proposed law. Moreover, in order to obtain intercepting the target in a finite time of flight, a new definition of the sliding surface is presented as the relative distance between the PROJECTILE and the target multiplied by the line of sight (LOS) angular rate. In order to increase the efficiency of the interception, the design parameters of the proposed law are optimized based on a multi-objective genetic algorithm (MOGA) using an objective function with a combination of the control effort, the miss distance and the time of flight criteria. Therefore, the proposed robust guidance law has the optimality properties. The simulation results are caused to decrease miss distance, decrease control effort, and decrease the time of flight, which indicates the effectiveness and accuracy of the proposed law compared to other corresponding methods.

Prediction of hydrodynamic loads during water impact has great significance in the structural design of vehicle. Impact load of fast crafts with water surface and the slam force of waves on the members of offshore structure is common examples of this phenomenon. There is not any available theoretical tool to exactly handle this complicated phenomenon and the experimental procedures in the laboratory are both time-consuming and expensive. Several studies has been done on impact to various structures from the water. Dependence of the solution of the problem to the change in the boundary shape of the water surface، makes the problem extremely complex and difficult to solve analytically. In this project، impact of a cylindrical PROJECTILE on the water surface at different entry velocities and entry angles is examined using Euler– Lagrange method in LS-DYNA software. Three-dimensional simulation and meshing of the body has been perform in LS-DYNA and then the water and the air model has been created. Simulation results with Specified boundary conditions indicate significant effect of velocity changes on the stress، plastic strain and reduce the velocity of the PROJECTILE on water impact.

In this paper, the problem of guidance in the mid-course of a PROJECTILE’ s flight has been addressed to meet the requirements and limitations of the homing phase. These requirements and constraints are usually for low cost systems that are required to increase their range, including the angle of priority (angle of view) and the flight path angle (the angle of impact) of the PROJECTILE along with the amount of control effort obtained in the mid-course. Obviously, if these requirements are met, the success of the PROJECTILE mission will increase. Therefore, considering the importance of the problem and despite the various and scattered works that have been done so far, in this research, first the mid-course guidance optimization problem of the PROJECTILE based on a performance function consisting of the control effort criterion, and also the final values of view angle and flight angle in the mid-course is defined as the penalty functions, respectively. Then, using the particle swarm optimization algorithm, optimal acceleration commands are generated. The simulation results compared with other methods show the proper functioning of the algorithm and its ability to solve more complex models.

A new experimental technique has been developed to measure the pressure distribution over the surface of a spinning wind tunnel model. The technique is unique in that all elements of the instrumentation, thus avoiding many of the technical problems and operational limitations associated with previous attempts to measure this effect. Surface pressure distributions were obtained for selected tip speed ratios for different angles of attack (5000rpm). The results obtained from the pressure profiles determine the Magnus forces and make it possible to interpret the boundary layer and the effects of separation. In this method, in addition to determining the Magnet force, its distribution on the model is also obtained. The results show that most of the Magnus force is created at the ends of the PROJECTILE. The validity of the data was established by comparing the integrated pressure values with directly measured balance data. Similar results were obtained by the numerical simulations and were compared with the experimental data. This new technique can be applied to a variety of model configurations and Mach number regimes.

Aerodynamic simulation of APDS PROJECTILE with and without sabot has been conducted here. Due to less weight of APDS PROJECTILE in comparison with the PROJECTILE, with the same caliber, APDS PROJECTILE has higher muzzle velocity, longer range, high penetration capability, and higher impact velocity. Simulation of flow around the sabot walls has been carried out in two opening degrees of zero and 75 at supersonic regime, using the 3D Spalart-Allmaras turbulence model. Problem verification has been tested, using the wind tunnel drag coefficient experimental data at two opening degrees of zero and 75 and close agreements have been obtained. The drag coefficient has been used in the ballistic coefficient calculations, wherein 24 percent improvement has been attained.

In this research the effect of the tumbling perforation of blunt-faced cylindrical PROJECTILEs in moderately thick aluminum plates is presented. The perforation process – depend on the impact angle in normal and oblique impact - consists of four stages: erosion, plugging, hole enlargement and petaling. The modeling in the plugging stage consists sequentially of cratering, plug formation, plug separation, plug slipping and post perforation deformation. In this analytical model, the target material is considered to be rigid perfectly plastic, while the PROJECTILE is regarded as adeformable. material PROJECTILE deformation depend on relative velocity of PROJECTILE occurs in three mode: erosion, flattening and rigid PROJECTILE. The effect of the frictional force is considered too. The new analytical results were found to be in good agreement with experimental results.