The bandwidth requirements of telecommunication network users increased rapidly during the last decades. Optical access technologies must provide the bandwidth demand for each user. The passive optical access networks (PONs) support a maximum data rate of 100 Gbps by using the Orthogonal Frequency Division Multiplexing (OFDM) technique in the optical access network. In this paper, the optical broadband access networks with many techniques from Time Division Multiplexing Passive Optical Networks (TDM PON) to Orthogonal Frequency Division Multiplex Passive Optical Networks (OFDM PON) are presented. The architectures, advantages, disadvantages, and main parameters of these optical access networks are discussed and reported which have many ad

We have studied theoretically the response of atomic three- level cascade scheme
of rubidium vapor to a strong laser under conditions in which electromagnetically
induced transparency would be induced on a weak probe beam. We show that the
medium that is an opaque to a probe laser can, by applying both lasers
simultaneously, be made transparent.

The aim of this novel native study was to determine the microbial contamination of broken and cracked imported commercial table egg in Baghdad markets and its economic effect. A total of 21510 commercial chicken table eggs were checked and surveyed from retail markets in different popular regions of Baghdad city during a year period from January 3^rd to December 28^th of 2018 and its microbial contamination were studied. Results revealed that significant differences (P<0.01) were appeared in the studied microbial counts during months of the study and significant differences (P<0.01) in the average counts between broken and cracked eggs and sound (not bro

Corrosion of Zn-Ni alloy coatings on stainless steel 316 SS in a chloride-sulfate bath with the addition of either triethanolamine or sucrose was examined. A constant cathode potential was used to deposit zinc-nickel alloys, while cyclic voltammetry and potentio-dynamic polarization were used to measure corrosion. In addition, scanning electron microscopy was utilized to analyse Zn-Ni alloy coating surface layers formed with¬out and with additives. The outcomes discovered that the corrosion resistance of Zn-Ni alloy coat¬ings in 3.5 % NaCl solution was highly influenced by adding triethanolamine or sucrose. Decreasing the Zn:Ni molar ratio led to an increase in corrosion resistance. All Zn-Ni alloy coatings were superior to pure Z

This study aimed to evaluate good manufacturing practices in food safety of ten different restaurants in the Al-Karkh area of Baghdad, Iraq. Forty samples collected from were collected from knives, food cutting boards, tables, hands and nails workers in restaurants. In addition. 70 food handlers were selected. Through structured interviews, information on the checklist for Good Manufacturing Practices in Food Safety, Food handlers’ general checklist for good hygiene, and Personal Hygiene Checklist were collected. The overall viable bacterial count before Good Hygiene Practices was significantly higher (P<0.05) than the total bacterial counts after Good Hygiene Practices. The highest viable bacterial counts before Good Hygiene P

This work deals with the production of light fuel cuts of (gasoline, kerosene and gas oil) by catalytic cracking treatment of secondary product mater (heavy vacuum gas oil) which was produced from the vacuum distillation unit in any petroleum refinery. The objective of this research was to study the effect of the catalyst -to- oil ratio parameter on catalytic cracking process of heavy vacuum gas oil feed at constant temperature (450 °C). The first step of this treatment was, catalytic cracking of this material by constructed batch reactor occupied with auxiliary control devices, at selective range of the catalyst –to- oil ratio parameter (  2, 2.5, 3 and 3.5) respectively.  The conversion of heavy vacuum gas

In this paper , concrete micro-piles were used to improve the bearing capacity of the soil which is supporting the shallow foundation by using groups of (4; 6 and 9)bored short micro-piles which have, (D=0.125m and D=0.1m), and length to diameter ratio (L/D) equal to (6; 10 and 12) respectively. To calculate the bearing capacity of the micro-piles,(Tomlinson) and (Lamda) methods were used; also the soil properties were taken from Al-Muthana airport,(Al-Qyssi,2001) [1]. The results show that; increasing the number of piles and/ or the diameters and lengths; and the interaction between the bearing capacity of the shallow foundation with the bearing capacity of the pile group which leads to increasing the strength against the external loads

The clayey soils have the capability to swell and shrink with the variation in moisture content. Soil stabilization is a well-known technique, which is implemented to improve the geotechnical properties of soils. The massive quantities of waste materials are resulting from modern industry methods create disposal hazards in addition to environmental problems. The steel industry has a waste that can be used with low strength and weak engineering properties soils. This study is carried out to evaluate the effect of steel slag (SS) as a by-product of the geotechnical properties of clayey soil. A series of laboratory tests were conducted on natural and stabilized soils. SS was added by 0, 2.5, 5, 10, 15, and 20% to the soil.