One of the unique properties of laser heating applications is its powerful ability for precise pouring of energy on the needed regions in heat treatment applications. The rapid rise in temperature at the irradiated region produces a high temperature gradient, which contributes in phase metallurgical changes, inside the volume of the irradiated material. This article presents a comprehensive numerical work for a model based on experimentally laser heated AISI 1110 steel samples. The numerical investigation is based on the finite element method (FEM) taking in consideration the temperature dependent material properties to predict the temperature distribution within the irradiated material volume. The finite element analysis (FEA) was carried out using the APDL scripting language (ANSYS Parametric Design Language) that is provided by the commercial code ANSYS. Infrared (IR) thermography technique was used to explore the workpiece surface and to validate the obtained results. The work takes into account the effect of different speeds of the laser beam and pulses overlap on the temperature pattern of the material surface and depth.
Q-switched lasers widely used in management skin diseases and
sometimes its effect may be inadequate or associated with
cytotoxicity. The current study aimed to investigate the effect of
Q-switched Nd:YAG laser upon cellular elements using in vitro
experimental model. Aqueous solutions of human albumin and pure
calf thymus double strand deoxyribonucleic acid (ctdsDNA)
irradiated with Q-switched Nd:YAG laser at different rates (1, 3 Hz)
and time exposure (up to 60 seconds) using 532 nm (400 mJ) and
1064 (1200 mJ) nm wavelength with fixed spot size of 4 mm. The
effect of laser irradiation on the albumin solution also studied in the
presence of elemental salts of copper, zinc and iron.
Q-switched laser irrad
This paper studied the behaviour of reinforced reactive powder concrete (RPC) two-way slabs under static load. The experimental program included testing three simply supported slabs of 1000 mm length, 1000 mm width, and 70 mm thickness. Tested specimens were of identical properties except their steel fibers volume ratio (0.5 %, 1 %, and 1.5 %). Static test results revealed that, increasing steel fibers volume ratio from 0.5% to 1% and from 1% to 1.5%, led to an increase in: first crack load by (32.2 % and 52.3 %), ultimate load by (36.1 % and 17.0 %), ultimate deflection by (33.6 % and 3.4 %), absorbed energy by (128 % and 20.2 %), and the ultimate strain by (1.1 % and 6.73 %). The stiffness and ductility of the specimens also increased. A
... Show MoreThe significance of the research conducted in northern Iraq comes despite the expansion of afforestation projects; yet, the suffering of the forests has increased due to their lack of scientific study, unpredictability of the climate, and adverse effects on the spread and growth of plant species Therefore, the goal of the study is to understand the effects of afforestation through a statistical analysis of plant diversity in northern Iraq and its distinctivenessThe analysis revealed that natural groupings had improved qualitatively more than other groups, particularly some dwindling species that are able to compete and occupy new areas. drought-prone vegetation, vegetation, and climat
This paper interest to estimation the unknown parameters for generalized Rayleigh distribution model based on censored samples of singly type one . In this paper the probability density function for generalized Rayleigh is defined with its properties . The maximum likelihood estimator method is used to derive the point estimation for all unknown parameters based on iterative method , as Newton – Raphson method , then derive confidence interval estimation which based on Fisher information matrix . Finally , testing whether the current model ( GRD ) fits to a set of real data , then compute the survival function and hazard function for this real data.
Autorías: Imad Kadhim Khlaif, Israa Gameel Hussein, Talib Faissal Shnawa. Localización: Revista iberoamericana de psicología del ejercicio y el deporte. Nº. 5, 2022. Artículo de Revista en Dialnet.
The cinematographer mediates through the means of cinema and television a set of elements complementing each other in the light of developments in various sciences, culture and arts for the purpose of conveying the meaning to the recipient and achieve aesthetic taste. Despite the diversity of cinematographic media with its multiple forms, The researcher started from the principle of definition and knowledge of a technical phenomenon that emerged in the cinematographic medium through the treatment of dramatic events through the solutions of the exit line depends on the narrative of events in one place contributes to attract Mam spectator since this interesting phenomenon in the mediator, there .van question arises the adoption of that vis
... Show MoreStuck pipe is a prevalent and costly issue in drilling operations, with the potential to cost the petroleum industry billions of dollars annually. To reduce the likelihood of this issue, efforts have been made to identify the causes of stuck pipes. The main mechanisms that cause stuck pipes include drill cutting of the formation, inappropriate hole-cleaning, wellbore instability, and differential sticking forces, particularly in highly deviated wellbores. The significant consequences of a stuck pipe include an increase in well costs and Non-Productive Time (NPT), and in the worst-case scenario, the loss of a wellbore section and down-hole equipment, or the need to sidetrack, plug, or abandon the well. This paper provides a comprehensive
... Show MoreThe present study investigates the application of a combined electrocoagulation-electrooxidation (EC-EO) process for the treatment of wastewater generated from Al-Dewaniya petroleum refinery plant in Iraq. The EC-EO process was examined in terms of its ability to simultaneously produce coagulant and oxidant agents by using a parallel plate configuration system composed of stainless steel plates as cathode and pair of aluminum and graphite plates as anode at two different current concentrations (1.92A/l and 0.96A/l). The results showed that the best conditions for treatment of Al-Dewaniya petroleum refinery wastewater using the combined approach were current concentration of (0.96A/l), current density