The present work provides theoretical investigation of laser photoacoustic one dimensional imaging to detect a blood vessel or tumor embedded within normal tissue. The key task in photoacoustic imaging is to have acoustic signal that help to determine the size and location of the target object inside normal tissue. The analytical simulation used a spherical wave model representing target object (blood vessel or tumor) inside normal tissue. A computer program in MATLAB environment has been written to realize this simulation. This model generates time resolved acoustic wave signal that include both expansion and contraction parts of the wave. The photoacoustic signal from the target object is simulated for a range of laser pulse duration 10ns-10μs emitted from Nd:YAG laser, depth of target object 0.3-3 cm, distance from the object to the detector 0.7-3 cm and the diameter of target object 0.1-0.6 cm. The diameter of the object computed by the simulation is always being 75% of its value. The amplitude of the signal is directly proportional with the laser pulse energy and inversely proportional with the depth of target object and the distance from the object to the detector. The PA signal is fully generated in Nano second laser pulse duration range as it is short enough to fulfill the stress confinement condition.
Background: Dimensional changes of acrylic denture bases after polymerization results in need for further adjustments or even ends with technical failure of the finished dentures. The purpose of this study was to estimate the linear dimensional changes for different palatal depths when using multiple investment materials and polymerization techniques. Materials and methods: Ninety upper complete denture bases were constructed for this study. They were divided into two main groups according to the polymerization methods: conventional water bath and experimental autoclave (short and long cycles). Each main group was further subdivided into three subgroups according to the palatal depth (shallow, medium and deep). Furthermore, for each palatal
... Show MoreMunicipal wastewater sources are becoming increasingly important for reuse, for irrigation purposes, so they must be treated to meet environmentally friendly local or global standards. The aim of this study is to establish, calibrate, and validate a model for predicting chemical oxygen demand for the pilot plant of mobile biofilm reactors operating from municipal wastewater in Maaymyrh located in Hilla city Using the approach of dimensional analysis. The approach of Buckingham's theorem was used to derive a model of dimensional analysis design for the forecast of (COD) in the pilot plant. The effluent concentration (COD) It has been derived as a result of the influential concentration of (COD), dissolved oxygen (DO), volume of pilot plant
... Show MorePublications are generally considered an effective visual artistic means that addresses the recipient (the audience), with the functional, aesthetic and expressive dimensions they carry that contribute to spreading a diverse cultural awareness, especially those publications that are concerned with their media, promotional and organizational performance, as well as specific cultural events at specific times, in pursuit Access to renewable and elaborate designs to achieve the functional and aesthetic purpose, as the completed design and construction process is subject to many variations, whether this diversity is intellectual or technical, internal or external, and all of them may overlap to obtain a comprehensive system of artistic format
... Show MoreThe theatrical show depends in its formation on the technical system and the elements that it has for the theatrical show, and among these techniques is the lighting, where every director looked for a style and method of implementing them and giving aesthetic functions and characteristics that give the theatrical show an aesthetic and interpretive dimension, and that is through multiple expressions and connotations of the lighting in giving the show a functional and aesthetic character. Therefore, light has been shed on the lighting and its action in the theatrical show, due to its significant role in the modern theatrical shows. The current research, thus, has been divided into four chapt
... Show MoreThroughout history, artists have played many important roles in society.
Generally speaking, the role of the artist is defined by the society he is part of.
Indeed, there are as many ideas as to the role of the artist and, ultimately the purpose
of art in society, as there are types of art. This is, as a matter of fact, neither a new
question- the dialogue has been present within art for centuries- nor probably one
that will ever fully be answered.
Tom Stoppard came to prominence in the mid-sixties, when art and politics
were closely linked, and theatre sought to change the world. Stoppard would have
none of that: his work has no overt message, no political program. In fact,
... Show MoreIn this study, a simulation model inside a channel of rectangular section with high of (0.16 m) containing two rectangular obstruction plates were aligned variable heights normal to the direction of flow, use six model of the obstructions height of (0.059, 0.066, 0.073, 0.08 and 0.087 m) were compared with the flow behavior of the same duct without obstructions. To predict the velocity profile, pressure distribution, pressure coefficient and turbulence kinetic energy flow of air, the differential equations which describe the flow were approximated by the finite volumes method for two dimensional, by using commercial software package (FLUENT) with standard of k-ε model two dimensions turbulence flow.
... Show MoreThe present study explores numerically the energy storage and energy regeneration during Melting and Solidification processes in Phase Change Materials (PCM) used in Latent Heat Thermal Energy Storage (LHTES) systems. Transient two-dimensional (2-D) conduction heat transfer equations with phase change have been solved utilizing the Explicit Finite Difference Method (FDM) and Grid Generation technique. A Fortran computer program was built to solve the problem. The study included four different Paraffin's. The effects of container geometrical shape, which included cylindrical and square sections of the same volume and heat transfer area, the container volume or mass of PCM, variation of mass flow rate of heat transfer fluid (HTF), and temp
... Show MoreNumerical simulations have been investigated to study the external free convective heat transfer from a vertically rectangular interrupted fin arrays. The continuity, Naver-Stockes and energy equations have been solved for steady-state, incompressible, two dimensional, laminar with Boussiuesq approximation by Fluent 15 software. The performance of interrupted fins was evaluated to gain the optimum ratio of interrupted length to fin length (
The present work intends to study of dc glow discharge were generated between pin (cathode) and a plate (anode) in Ar gas is performed using COMSOL were used to study electric field distribution along the axis of the discharge and also the distribution of electron density and electron temperature at constant pressure (P=.0.0mbar) and inter electrode distance (d=4 cm) at different applied voltage for both pin cathode system and plate anode and comparison with experimental results.