Abstract

      In this study, we compare between the autoregressive approximations (Yule-Walker equations, Least Squares , Least Squares ( forward- backword ) and Burg’s (Geometric and Harmonic ) methods, to determine the optimal approximation to the time series generated from the first - order moving Average non-invertible process, and fractionally - integrated noise process, with several values for d (d=0.15,0.25,0.35,0.45) for different sample sizes (small,median,large)for two processes . We depend on figure of merit function which proposed by author Shibata in 1980, to determine the theoretical optimal order according to min

Sultan Said bin Sultan bin Ahmed bin Said Al-Busaidi (1223-1273 AH / 1806-1856 AD) was able to rule Oman and Zanzibar in a unified Arab-African state during his reign. However, it was separated for several reasons. Thus, the study aims to clarify the efforts made by Sultan Said for annexing Zanzibar to Oman, establishing the Arab-African Sultanate, and shedding light on the role played by Britain in dividing the Arab-African Sultanate and separating Zanzibar from the Omani rule in (1275 AH-1861 AD). The study has adopted the historical descriptive analytical approach. The study has reached several conclusions, such as: The economic motivators  were the most important factors that pushed Sultan Said to move his capital from Muscat to

Background: The apical seal is the single most important factor in determining the success of surgical endodontics, the aim of this study was to compare the sealing ability of Mineral Trioxide Aggregate in three different cavity designs. Materials and Methods: Thirty extracted human single-rooted teeth were divided into three groups of ten teeth per group, a retrograde cavity preparation was carried out using a low speed handpiece and round bur with parallel walls in the first group, ultrasonic retrotip and unit in the second group and a low speed handpiece with a carbide inverted cone bur with undercuts in the third group, all the cavities were filled with MTA. microleakage was measured by dye penetration technique using methylene blue. Re

The magnetic properties of a pure Nickel metal and Nickel-Zinc-Manganese ferrites having the chemical formula Ni_0.1(Zn_0.4Mn_0.6)_0.9Fe₂O₄ were studied. The phase formation and crystal structure was studied by using x-ray diffraction which confirmed the formation of pure single spinel cubic phase with space group (Fd3m) in the ferrite. The samples microstructure was studied with scanning electron microstructure and EDX. The magnetic properties of the ferrite and nickel metal were characterized by using a laboratory setup with a magnetic field in the range from 0-500 G. The ferrite showed perfect soft spinel phase behavior while the nickel sample showed higher magnetic loss an

KE Sharquie, AA Noaimi, SJ Murtada…, Journal of Cosmetics, Dermatological Sciences and Applications, 2016 - Cited by 4

Desert truffle is considered as a type of Syrian wild fungi that spreads heavily, and it occupies important rank in folk medicine, where its aqueous extract is used for the treatment of some eye and skin illnesses, and people prefer the use of black truffle. This work interested in studying of the most available species; Terfezia claveryi (black) and Tirmania pinoyi (white). The extracts of the two species of truffle were prepared by maceration with water, methanol, and ethanol 70%. Their total phenolic contents (TPC) and total flavonoid contents (TFC) were analyzed using Folin-ciocalteu and Aluminum chloride methods respectively, and their antioxidant activities was tested using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and

The methods used by the print media (press) is varied in conveying its messages and its orientations to the readers. But language takes the leading method among these methods, or a real competitor - so far - due to the characteristics and advantages of languages, including: ease, abbreviation, and development, etc.

In the midst of such events, political tensions, and what they carry of the global developments, and among which was the most important the fall of the former Iraqi regime in the spring of 2003, the press had the greatest share, and a large portion on the level of monitoring, analyzing, and interpreting the various consequences of the event. The interpreting of the news varies according to the evolving political trends

In this time, most researchers toward about preparation of compounds according to green chemistry. This research describes the preparation of 2-fluoro-5-(substituted benzylideneamino) benzonitrile under reflux and microwave methods. Six azomethine compounds (B1-6) were synthesized by two methods under reflux and assisted microwave with the comparison between the two methods. Reflux method was prepared of azomethine (B1-6) by reaction of 5-amino-2-fluorobenzonitrile with some aldehyde derivatives with (50–100) mL of absolute ethanol and some quantity of GAA and time is limited between (2–5) hours with a yield between (60–70) percent with recrystallization for appropriate solvents. But the microwave-assisted method was synthesized of co