Visible Light Communication (VLC) has emerged as a powerful technique for wireless communication systems. Providing high data rate and increasing capacity are the major problems in VLC. Recent evidence suggests that Multiple Input Multiple Output (MIMO) technique can offers improved data rates and increased link range. This paper describes the design and implementation of visible light communication system in indoor environment exploring the benefits of MIMO. The specific objective of this research was to implement a 4× 4 Multiple Input (LEDs) Multiple Output (photodetectors)-VLC communication system, where a 16 white power LEDs in four arrays are setting up at transmitter and four RX modules are setting up at receiver side without the need for additional power or bandwidth as well as analyze a mathematical model for a VLC-× 4 MIMO with different modes such as the suitable angles to cover the entire room. The research designs practically an electronic circuit for the transmitter and receiver with inexpensive components. The power distribution of different propagation modes is calculated for Single Input Single Output (SISO) and MIMO channels in typical room dimensions. The results in this paper indicate that the power is distributed uniformly for entire room when implemented VLC-MIMO as compared to VLC-SISO. Furthermore, a 4× 4 MIMO implementing VLC is compared in term of BER vs. SINR with SISO communication system for both Line of Sight (LOS) and Non Line of Sight (NLOS) propagation modes. Comparing the two results of LOS and NLOS, it can be seen that a 4× 4 MIMO implementing VLC for LOS perform better …
The purpose of this study is to identify the extent of the EFL teachers’ implementationoftotal quality management (TQM)principles through teaching English as a foreign language in Iraqi secondary schools.A total of 180 EFL teachers fromsecondary schools in Baghdad during the academic year 2010/ 2011 participated in the study. Data was collected using a scale to identify the extent of implementation of total quality management principles by 140 EFL teachers in their classroom. To support the data collected from the scale,40 teachers were observed by EFL educational supervisors during their lessons. The collected data was analyzed using frequency, means and standard deviation to identify the extent of implementation of (TQM) principles.
... Show MoreThe modern and contemporary history of Libya has attracted the attention of researchers during the nineties of the last century and beyond.
The subject of ((Jewish activity in Libya 1911 AD - 1951 AD)), and the nature of follow - up economic and social activities and political participation has remained poor in terms of study and follow - up, because of the scarcity of sources, especially documentary ones. The research will reveal within its axes the most important of these activities.
One of the main aims of Metrical Phonology Theory (MTT) is to provide the stress of poetry on the syllable, the foot, and the phonological word levels. Analyzing poetry embodies one of the most prominent and controversial metrical issues as the subsumed number and types of syllables, feet, and meters are balanced compared to other literary texts. The MTT saw the light during the late seventies (1975) and (1977) by Liberman and Prince, who produced it as part of non-linear phonology. Its roots originated in prosody, which studies poetic meter and versification. The basis of the metrical analysis is the prosodic analysis developed in London by Firth and his students in 1950. This study aims to identify the values of five metri
... Show MoreThe person who wants to learn. The history of Bab’is will notice a very
starnge phenomenon that they (Babis and Baha’is) resort to visions to prove their
delusion.
The believers usually reach to each other by their visions. This phenomenon
are shared among them from Al- Ahsa’ai time till the last phase of their propaganda
which is the Baha’is propaganda, and this is due to their ignorance and under
development in doctrine of islam which was widespread in Iran and the Islamic world.
The whole secrets of Babis and Baha’is movement were restricted among
particular group, most of them were Al- Rashti’s students and knew the basic
principles of their movement which deperding or (the principles) declarati
Abstract of the research:
This research sheds light on an important phenomenon in our Arabic language, which is linguistic sediments, and by which we mean a group of vocabulary that falls out of use and that native speakers no longer use it, and at the same time it happens that few individuals preserve the phenomenon and use it in their lives, and it is one of the most important phenomena that It should be undertaken and studied by researchers; Because it is at the heart of our huge linguistic heritage, as colloquial Arabic dialects retain a lot of linguistic sediments, and we usually find them at all levels of language: phonetic, banking, grammatical and semantic. In the
... Show MoreThe research aims to identify the predominant habits and behaviors promoted by American action films frequently streamed on Cinemana website—a specialized platform for streaming films and series as the most followed platform. This platform offers a range of film genres, including the latest releases, free of charge. Using a simple random sampling method, twenty action films were selected for the study. Consequently, the researcher opted for a descriptive-analytical approach, deemed most appropriate for achieving the research objectives, employing content analysis as a tool to scrutinize these films. The findings highlighted that behavioral habits associated with scenes of violence, destruction, sabotage, revenge
... Show MoreIt is the dynamic tension between the relatively fixed built environment and the constantly changing in social life that determines the nature of urban spaces belonging to different historical periods, and considered as a tool for diagnosing transformations in urban spaces, that’s why, the characteristics of urban space became unclear between positive spaces and negative spaces, so emerged the need to study contemporary urban space belonging to the current period of time and show the most important transformations that have occurred in contemporary urban space to reach urban spaces that meet the current life requirements. Therefore, the research dealt with a study of the characteristics of contemporary urban space and the most pr
... Show MoreMelatonin, a hormone synthesized mainly by the pineal gland, has been found in extra-pineal organs as well. It’s known as an organizer of circadian rhythms and more recently as an anti-oxidant. In addition to its role in maintaining immunity, pathophysiology of cardiovascular and neurological diseases, and as an anti-cancer agent, evidence has demonstrated that melatonin exerts a positive impact on male and female fertility primarily through oxygen scavenging effects. In In Vitro Fertilization (IVF) programs, supplementation of melatonin may be associated with better outcomes in terms of sperm quality, oocyte quality, embryo quality and pregnancy rates. This review summarizes various actions of melatonin on the body focusing on male an
... Show MoreIn this study, NaOH dissolution method was applied to dissolve cellulose fibers which extracted from date palm fronds (type Al-Zahdi) taken from Iraqi gardens. In this process, (NaOH)-solution is brought into contact with the cellulose fibers at low temperature. Experiments were conducted with different concentrations of NaOH (4%, 6%, 8% and12%) weight percent at two cooling bath temperatures (-15 oC) and (-20oC). Maximum cellulose dissolution was 23 wt% which obtained at 8 wt% concentration of NaOH and at cooling bath temperature of -20oC. In order to enhance the cellulose fibers dissolution, the sample was pretreated with Fenton's reagent which consists of hydrogen peroxide (H2O2), oxalic acid (C2H2O4) and ferrous sulfate (FeSO4). This
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