In this paper, a sufficient condition for stability of a system of nonlinear multi-fractional order differential equations on a finite time interval with an illustrative example, has been presented to demonstrate our result. Also, an idea to extend our result on such system on an infinite time interval is suggested.
The aesthetic expression and its orders are important for steel structures forming. Steel structures are a compilation of structural elements, where its shapes have standard dimensions and pre-fabricated. As the steel construction systems not only aim to achieve the functional requirements for users, but must also have the symbolic aesthetics which provides visually and cognitive expression for viewers. In this sense the research interested in expressional aesthetics in these systems and highlights the importance of attention as structural items. Therefore the visual items which related with steel structures contain some of the most powerful forms of modern architecture, steel structures with a glass cladding, agility an
... Show MoreBaghdad Metro is a vital project to fulfill the rapidly increased traffic volume requirements. The proposed metro will connect both sides of Baghdad City, passing under the Tigris River. This study is employed finite elements software (PLAXIS 3D) to evaluate the seepage force developed around the sub-river segment during different construction stages and for other water levels of Tigris. The study found that when the water level changes from maximum to minimum, the developed seepage force decreases by (8 to 13%) and (22 to 27%) respectively. The seepage forces were found to be maximum during the excavation stage. The concrete lining process led to a noticeable reduction in seepage forces at all locations. The study also
... Show MoreDates are considered one of the most important foods consumed in Arab countries. Dates are commonly infested with the sawtoothed grain beetle, Oryzaephilus surinamensis. Consequently, the date yield, quantity, and quality (economic value and seed viability) are negatively affected. This study was designed to investigate the effectiveness of air evacuation as eco-friendly and safe control method against adult O. surinamensis. Insects were obtained from the infested date purchased from a private store in sakaka city, Aljouf region, Saudi Arabia. Air evacuation (using a vacuum pump) and food deprivation were applied to O. surinamensis, and insect mortality was observed daily in comparison with the control group (a
... Show MoreStriae distensae SD or stretch mark are frequent skin lesion that cause considerable aesthetic concern. The 1064nm long pulsed Nd:YAG Laser has been used to promote an increase in dermal collagen and is known to be a Laser that has a high affinity to vascular chromphores. Also by using fractional CO2 Laser 10600nm as an effective modality in treatment of striae distensae SD. It works to stimulate fibroblast and enhance Collagen formation, which is important for newly generated skin tissue.
Objectives: This study aims to verify the efficacy of long pulsed Nd: YAG Laser (1064nm) in the treatment of immature striae distensae (SD) and the efficacy of C02 fractional Laser (10600nm) in treatment o
... Show MoreIt is often noted that disordered materials have different chemical properties to their more “ordered” cousins. Quantifying these effects in terms of thermodynamics is challenging in part because disordered materials can be difficult to characterize and are frequently relatively unstable. During the course of our experiments to understand the effects of disorder in catalysts for water oxidation we observed that many disordered manganese and cobalt oxide water oxidation catalysts directly oxidized peroxide in contrast to their more ordered analogues which catalyzed its disproportionation, that is, MnO2+2H+ +H2O2! Mn2+ +2H2O+O2(oxidation) versus H2O2!H2O+1=2 O2(disproportionation). By measuring the efficiency for one reaction over the oth
... Show MoreThe proposed work is an attempt to investigate the stability of the nonlinear system by using a whale optimization algorithm as of one of the meta-heuristic optimization methods, and this investigation was conducted on a single inverted pendulum as a study model. The evaluation measures which were used in this article values of gain and sliding surface of the conventional sliding mode controller to illustrate the extent of the system`s stability. Furthermore, control action, the relationship between error and its derivative, desired, and actual position in addition to sliding response graphically showed the feasibility of the proposed solution. The attained results illustrated considerable improvement in the settling time and minimizing the
... Show MoreStudies were conducted to screen eight sunflower (Helianthus annuus L.) genotypes for their allelopathic potential against weeds and wheat crop, which customarily follows sunflower in Iraq. All sunflower genotypes significantly inhibited the total number and biomass of companion weeds and the magnitude of inhibition was genotype dependent. Among the eight genotypes tested, Sin-Altheeb and Coupon were the most weed-suppressing cultivars, and Euroflor and Shumoos were the least. A subsequent field experiment indicated that sunflower residues incorporated into the field soil significantly inhibited the total number and biomass of weeds growing in the wheat field. Sunflower genotypes Sin-Altheeb and Coupon appeared to inhibit total weed number
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