Tungsten inert gas arc welding–based shaped metal deposition is a novel additive manufacturing technology which can be used for fabricating solid dense parts by melting a cold wire on a substrate in a layer-by-layer manner via continuous DC arc heat. The shaped metal deposition method would be an alternative way to traditional manufacturing methods, especially for complex featured and large-scale solid parts manufacturing, and it is particularly used for aerospace structural components, manufacturing, and repairing of die/molds and middle-sized dense parts. This article presents the designing, constructing, and controlling of an additive manufacturing system using tungsten inert gas plus wire–based shaped metal deposition method. The aim of this work is to design and develop tungsten inert gas plus wire–based shaped metal deposition system to be used for fabricating different components directly from computer-aided design data with minimum time consumed in programming and less boring task compared to conventional robotic systems. So, this article covers the important design steps from computer-aided design data to the final deposited part. The developed additive system is capable of producing near-net-shaped components of sizes not exceeding 400 mm in three-dimensional directly from computer-aided design drawing. The results showed that the developed system succeeded to produce near-net-shaped parts for various features of SS308LSi components. Additionally, workshop tests have been conducted in order to verify the capability and reliability of the developed additive manufacturing system. The developed system is also capable of reducing the buy-to-fly ratio from 5 to 2 by reducing waste material from 1717 to 268 g for the sample components.
In this paper, customers’ expectations are continually shifting due to the business environment’s growing competition and substantial changes. As a result, organisations no longer viewed it as a static objective but as an ever-evolving aim. From this vantage point, the research has explored the accounting literature in search of novel approaches to addressing the strategic dimensions of quality, cost and time. Getting them to respond positively to the customer’s requests also requires recognising their needs and controlling their impact on these dimensions. With the removal of operations that do not contribute any value to the product’s value chain and a reduction in manufacturing costs through continuous improvement, the ou
... Show MoreThe development of thyroid gland in five developmental stages of common carp, Cyprinus carpio L. The thyroid originates from the pharyngeal floor as a median ventral keel in late embryos having four pairs of arches. It differentiates into profollicular aggergations and true follicles with flattened walls and empty lumina or with lumina filled with cotton waste-like material in three days-old elvers. Secretion of homogeneous eosinophilic colloid with a limited increase in the height of follicular wall is noted in five days-old elvers. In nine days-old individuals the follicles increase in size due to coallescence. The thyroid gland reaches its maximal activity as judged by its histology in one-two months-old individuals. The gland is of t
... Show MoreThis research aims at highlighting the strategic role of human resource development in developing competitive advantage in light of the great challenges and rapid changes witnessed in recent years in the business world. The human element is the main engine of the organization's resources, especially when it possesses the skill quality and cognitive abilities commensurate with the nature of work. Therefore, this research focuses on the importance of human resources development strategy in contemporary organizations and reviews the summary of literature and theoretical foundations related to human resources development, as well as various philosophical concepts related to the competitive advantage and to indicate the important role
... Show MoreThe study concerned the embryonic development of spinal cord of white choeked bulbul Pycnonotus leucotis. The spinal cord at the age 40 hour’s incubation from the neural tube and its tissue wall is composed of two layers, the ependymal layer and mantle layer. The spinal cord differentiation is completed at the age 7 day’s incubation, its, were we notice that the central canal is clear and cavity lined with neurons and we note the arrangement of gray matter in the form of the letter H and its inside and it is characterized by dorsal and ventral horns and the gray matter substance and note the formation of dorsal medium spetum and ventral medium fissure.
Chapter One : the importance of research and the need for it .
He has developed the concept of the curriculum has evolved as other educational concepts . Because the world has become a small village due to modern technology and are used in various aspects of life , and the rapid communication between the world can be accessed easily and conveniently . And that the purpose of education citizens who create social functions which ones to keep the culture , upgrade and repair flaws, and aims to develop the capacity of the individual and the preparations in the footsteps of scientific and technological development .
- The goal of research : The research aims to:
1 . What is the
The research aims at clarifying the role of green human resource management practices in achieving sustainable development. The research problem is that the health sector is less concerned with environmental aspects, specifically green human resource management practices, Which are reflected on sustainable development with their economic, environmental and social dimensions as well as reducing costs, waste minimization and recycling, And the research started from two main hypotheses to explore the correlation and influence between the variables of the research by analyzing the answers of the research sample, which included (136) employees of the Al-Imamein Al-kadhemein medical city, Data and information were collected using quest
... Show MoreIn this study, a different design of passive air Solar Chimney(SC)was tested by installing it in the south wall of insulated test room in Baghdad city. The SC was designed from vertical and inclined parts connected serially together, the vertical SC (first part) has a single pass and Thermal Energy Storage Box Collector (TESB (refined paraffin wax as Phase Change Material(PCM)-Copper Foam Matrix(CFM))), while the inclined SC was designed in single pass, double passes and double pass with TESB (semi refined paraffin wax with copper foam matrix) with selective working angle ((30o, 45o and 60o). A computational model was employed and solved by Finite Volume Method (FVM) to simulate the air i
... Show MoreAn annular two-phase, steady and unsteady, flow model in which a conductingfluid flow under the action of magnetic field is concavely. Two models arepresented, in the model one; the magnetic field is perpendicular to the long side ofthe channel, while in the model two is perpendicular to the short side. Also, westudy, to some extent the single-phase liquid flow.It is found that the motion and heat transfer equations are controlled by differentdimensionless parameters namely, Reynolds, Hartmann, Prandtl, and Poiseuilleparameters. The Laplace transform technique is used to solve each of the motion andheat transfer equations. The effects of each of dimensionless parameters upon thevelocity and heat transfer is analyzed.A comprehensive study fo
... Show MoreFor over a decade, educational technology has been used sparingly in our schools and universities. Online training courses have been used since 2003 to fill the gaps in our learning system and to add extra program besides classroom learning. This paper aims to investigate the Iraqi EFL instructors’ participating in online training courses and its influence on the process of teaching and learning.
The sample of present study consists of 30 instructors from University of Baghdad. The questionnaire of sixteen items was constructed. After ensuring validity and reliability of questionnaire, it was applied on March 2013 and the result shows that most of instructors improve their teaching methods b
... Show MorePolymeric hollow fiber membrane is produced by a physical process called wet or dry/wet phase inversion; a technique includes many steps and depends on different factors (starting from selecting materials, end with post-treatment of hollow fiber membrane locally manufactured). This review highlights the most significant factors that affect and control the characterization and structure of ultrafiltration hollow fiber membranes used in different applications.
Three different types of polymers (polysulfone PSF, polyethersulfone PES or polyvinyl chloride PVC) were considered to study morphology change and structure of hollow fiber membranes in this review. These hollow fiber membranes were manufactured with different pro
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