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This study aims to review the recent techniques in digital multimedia compression with respect to fractal coding techniques. It covers the proposed fractal coding methods in audio and image domain and the techniques that were used for accelerating the encoding time process which is considered the main challenge in fractal compression. This study also presents the trends of the researcher's interests in applying fractal coding in image domain in comparison to the audio domain. This review opens directions for further researches in the area of fractal coding in audio compression and removes the obstacles that face its implementation in order to compare fractal audio with the renowned audio compression techniques.

A laboratory coking unit was designed and constructed for an experimental study of the delayed coking process of hydrotreated Kirkuk reduced crude. The yield and analysis of coke, gases and liquid products were obtained for each experiment. The gas < C4. and gasoline yield decrease by increasing Liquid hourly space velocity (LHSV) while the yields of kerosene and gas oil increase and no effect of LHSV on petroleum coke yield was observed, The specific gravity of gasoline, kerosene and gas oil decreases by increasing LHSV. The increase in LHSV (decrease in residence time) decreases the olefinic hydrocarbons of produced gas oil and fraction 350-450°C. Sulfur content of produced coke and coking residue increases by increasing residence time while it changes slightly for kerosene and gas oil. By increasing the recycle ratio (RR), the yield of gas decreases while the coke yield increases. Sulfur content of gas oil and coking residue increases with an increase in the recycle ratio while it decreases fo...

The thermal stabilities of petroleum distillates with boiling point (b.p.) in the range 250–425 °C produced from a medium Iraqi crude oil were evaluated using different thermoanalytical techniques: differential scanning calorimetry; thermogravimetry; and differential thermogravimetry. Results obtained from these methods were correlated with some of the physico-chemical properties of the distillates studied. It was shown by differential scanning calorimetry that the stability of the distillates increased with increase in their total aromatic constituents, but was not related to the total content of sulphur compounds present. Thermogravimetry indicated that the thermal stabilities of the distillates increased with increase in their corresponding average molecular weights.