Computational study of three-dimensional laminar and turbulent flows around electronic chip (heat source) located on a printed circuit board are presented. Computational field involves the solution of elliptic partial differential equations for conservation of mass, momentum, energy, turbulent energy, and its dissipation rate in finite volume form. The k-ε turbulent model was used with the wall function concept near the walls to treat of turbulence effects. The SIMPLE algorithm was selected in this work. The chip is cooled by an external flow of air. The goals of this investigation are to investigate the heat transfer phenomena of electronic chip located in enclosure and how we arrive to optimum level for cooling of this chip. These par
... Show MoreIn this paper, a theoretical study of the energy spectra and the heat capacity of one electron quantum dot with Gaussian Confinement in an external magnetic field are presented. Using the exact diagonalization technique, the Hamiltonian of the Gaussian Quantum Dot (GQD) including the electron spin is solved. All the elements in the energy matrix are found in closed form. The eigenenergies of the electron were displayed as a function of magnetic field, Gaussian confinement potential depth and quantum dot size. Explanations to the behavior of the quantum dot heat capacity curve, as a function of external applied magnetic field and temperature, are presented.
Atorvastatin have problem of very slightly aqueous solubility (0.1-1 mg/ml). Nano-suspension is used to enhance it’s of solubility and dissolution profile. The aim of this study is to formulate Atorvastatin as a nano-suspension to enhance its solubility due to increased surface area of exposed for dissolution medium, according to Noyes-Whitney equation.
Thirty one formulae were prepared to evaluate the effect of ; Type of polymer, polymer: drug ratio, speed of homogenization, temperature of preparation and inclusion of co-stabilizer in addition to the primary one; using solvent-anti-solvent precipitation method under high power of ultra-sonication.
... Show MorePurpose: The research aims to explore the impact Business Intelligence System (BIS) and Knowledge Conversion Processes (KCP) in the Building Learning Organization (LO) in KOREK Telecom Company in Baghdad city.
Design/methodology/approach: in order to achieve the objectives of the research has been the development of a questionnaire prepared for this purpose and then has tested the search in the telecommunications sector, representatives of one of the telecommunications companies in Baghdad city, has therefore chosen KOREK Telecom company as a sample for research, and the choice was based on the best standard international companies to serve mobile communications in terms o
... Show MoreThis research seeks through the adoption of two basic variables, where he considered the actuarial experience as an independent variable, while the process of accepting the risk and dimensions related to it is a dependent variable, the research was adopted to present the data achieved by the company during the life insurance business during the adoption of actuarial experience at the beginning of its work where Adoption of the historical method in the analysis of those data to prove the researcher's opinion, through the analysis of data (5 years) for the first period, which extends between (1975-1979), the period during which the company adopted the actuarial experience at the time, also taken data for the same dimensions related to the
... Show MoreConcrete is the main construction material of many structures. Exposing to loads creates cracks in concrete, which reduce the performance and durability. The decrease of concrete cracks becomes a necessity demand to ensure more durability and structural integrity of the concrete structure. Autogenous healing concrete is a kind of new smart concretes, which has the ability to reclose its cracks by means of itself. Concrete self-healing is a type of free repairs processes, which is reduce direct and indirect cost of maintenance and repairing. This work targets to inspect the mechanical properties of concrete after using two combinations of two materials (20 kg/m3 calcium hydroxide Ca(OH
All alive languages had passed linguistic changes that made the mother language not recognized by its present speakers. Some of these changes are: syntactical, semantical, orthographical, phonetical and lexical.During the period of changes which extends over centuries, there had been a lof of written texts, such as literately texts, biographies, personal memories and manuscripts which are conserved until now as a literatel, historic and linguistic testimonies.Spanish is one of these languages that had been changed, so, the poem of the Cid (1145) was written in a Spanish which differs from the Spanish in which Cervantes wrote the Don Quixote in (1605/1615) and the Spanish of both of them differs from the Spanish of Francisco Ayala and Azorin
... Show MoreCuáles son los escritores que aun triunfan en España? ¿A cuáles tendencias o escuelas representan? ¿Todavía mantiene prestigio fecundo en el estudio literario? A todas tales preguntas queríamos ofrecer nuestro planteamiento investigativo en la página de las más importantes de la literatura española contemporánea, pero según nuestro punto de ver a las cosas.
La panorámica de la literatura española a partir del año 1860 no ofrece un tema o un estilo mutuamente románticos, aun cuando en este romanticismo decaído ya se advierten muy acusados los tones que se decoloran y los dibujos que se desvanecen. De esta realidad surge la necesidad del toque tan importante como el de Ramón del Valle Inclán cuya obra se encuentra nue
El presente trabajo es un estudio sintáctico y práctico en que se trata de explicar el funcionamiento de "ya" en la oración, el objetivo principal de este estudio es el análisis del complejo significado de "ya" teniendo en cuenta el modo de la acción del verbo sobre el que incide semánticamente el adverbio.
En este estudio empírico aclaramos los distintos valores de "ya" e intentamos demostrar que es un adverbio que significa una determinada modalidad del enunciado.
Pero antes de explicar detalladamente nuestro estudio presentaremos un resumen del adverbio en general , porque "ya" es uno de los adverbios de tiempo , este p
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