In this paper, simulation study of the frequency shift of photonic bandgaps due to refractive index scaling using liquids filled hollow-core photonic crystal fibers is presented. Different liquids (distilled water, n-hexane, methanol, ethanol and acetone) are used to fill the cladding of 2 types of hollow core photonic crystal fibers (HC19-1060, HC7-1060). These liquids are used to change the effective index scaling and index contrast of the cladding. The effect of increasing temperature of the liquid (20-100 0C for water and 20-70 0C for other liquids ) infiltrated hollow core fiber on the bandgap width and transmission properties has been computed. The maximum photonic bandgap width at 0.0243 has appeared with filling HC7-1060 PCF with methanol at 70 0C at a corresponding refractive index 1.3057. Photonic bandgap structure for both TE and TM modes of a 2D photonic crystal with triangular lattice of air holes embedded in silica background material was studied using Plane Wave Expansion (PWE) method to find the width of photonic bandgap finger in photonic crystal states diagram.
Abstract
The research addresses the specification table and the extent of its use in developing achievement tests, as well as detects the obstacles to its use through a sample of (120) respondents from the faculty members in some Baghdad schools and colleges. After unpacking and processing the data statistically, the research reached several results: the study sample do not use the test map in the development of their tests, as their percentage reached (82%) and there are no statistically significant differences in the use of the specification table by the sample members according to their place of work or the number of years of experience. The results also revealed the most important reasons that prevent the use
... Show MoreObjectives: To assess the premenstrual syndrome among the working women in Baghdad City.
Methodology: A cross-sectional analytic study, using probability sampling cluster (multi-stage) sampling of
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designed and consisted of (4) parts, including demographic, reproductive, menstrual cycle characteristics, and
premeustmual syndrome symptoms. Content validity and reliability of the questionnaire were detemined by
conducting a pilot study. Descriptive and inferential statistical procedures were used to analyze the data.
Results: The results of the study revealed that the age of women ranged betwee
Communication and media technologies have seen several changes in the last two decades. These changes put the basis for the emergence of communicative and media practices on several levels including political, economic, technological and artistic. And these, in turn, led to the emergence of new media trends and phenomena in various areas of media worthily to be studied and researched for example online advertisings. Online advert
... Show MoreBackground: Animal bites in humans are an important public health problem. Most of these bites are dog bites. Dog bites in humans are a complex problem embracing public health and animal welfare, both in developed and developing nations. .
Al-kindy Col Med J Vol.8 No.2 2012 P: 149
Objectives: in order to estimate the magnitude of the problem and to understand the epidemiological characteristics of dog bite victims registered in Baghdad city regarding their age, sex, number of registered dog bite victims per month and year along the studied period ( 2006-2010) and also to sniff out any seasonal variation in dog bite attacks .
Methods: A across-sectional study was carried out during January (2011), in the Anti-Rabies clinic of (Pa
It is clear that correct application of antibiotic prophylaxis can reduce the incidence of infection resulting from the bacterial inoculation in a variety of clinical situations; it cannot prevent all infections any more than it can eliminate all established infections. Optimum antibiotic prophylaxis depends on: rational selection of the drug(s), adequate concentrations of the drug in the tissues that are at risk, and attention to timing of administration. Moreover, the risk of
... Show MoreABSTRACTBackground: cochlear implants are electronic devices that convert sound energy into electrical signals to stimulate ganglion cells and cochlear nerve fibers. These devices are indicated for patients with severe to profound sensorineural hearing losses who receive little or no benefit from hearing aids. The implant basically takes over the function of the cochlear hair cells. The implant consists of external components (microphone, speech processor and transmitting coil) and internal components (receiver stimulator and electrode array). The implant is inserted via a trans mastoid facial recess approach to the round window and scala tympani.Objectives: to determine the effectiveness and safety of non fixation method in cochlear imp
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The main problem of this research titled (the prevailing scientific values in children's programs provided by the channel (mbc3) is the disclosure of the scientific values that are included in the children's program in the mbc3 channel) which are directed to an important group of society, which is the category of children who spend long hours in front of TV screens to watch these programs, and therefore they acquire many values that can replace fixed values, such as social, moral, religious, etc., and the content analysis method has been used to analyze children's programs presented by mbc3 channel), and the research has reached a number of The results can be summarized b To come: |
As the bit rate of fiber optic transmission systems is increased to more than , the system will suffer from an important random phenomena, which is called polarization mode dispersion. This phenomenon contributes effectively to: increasing pulse width, power decreasing, time jittering, and shape distortion. The time jittering means that the pulse center will shift to left or right. So that, time jittering leads to interference between neighboring pulses. On the other hand, increasing bit period will prevent the possibility of sending high rates. In this paper, an accurate mathematical analysis to increase the rates of transmission, which contain all physical random variables that contribute to determine the transmission rates, is presen
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