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Presentation of Malaria Epidemics Using Multiple Optimal Controls
Lashari, Abid Ali,Aly, Shaban,Hattaf, Khalid,Zaman, Gul,Jung, Il Hyo,Li, Xue-Zhi Hindawi Limited 2012 Journal of applied mathematics (JAM) Vol.2012 No.-
<P>An existing model is extended to assess the impact of some antimalaria control measures, by re-formulating the model as an optimal control problem. This paper investigates the fundamental role of three type of controls, personal protection, treatment, and mosquito reduction strategies in controlling the malaria. We work in the nonlinear optimal control framework. The existence and the uniqueness results of the solution are discussed. A characterization of the optimal control via adjoint variables is established. The optimality system is solved numerically by a competitive Gauss-Seidel-like implicit difference method. Finally, numerical simulations of the optimal control problem, using a set of reasonable parameter values, are carried out to investigate the effectiveness of the proposed control measures.</P>
Sarir Uddin,Abid Zaman,Imtiaz Rasool,Sadiq Akbar,Muhammad Kamran,Nasir Mehboob,Asad Ali,Abid Ahmad,Muhammad Farooq Nasir,Zafar Iqbal 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.6
The effects of Ba substitution on the phase analysis, microstructure and microwave dielectric properties of Ca1-xBaxTiO3ceramics were prepared through conventional solid state reaction route. The X-ray diffraction analysis of the samples showedthat the specimens Ca1-xBaxTiO3 presented single phase compound with orthorhombic structure in the range of x=0.0 to 0.7when sintered at 1300oC for 3hrs in air. From the morphological point of view, it consists of round and rod shaped grains withporous microstructure. The substitution of Ba2+ ions over Ca2+, the microwave dielectric constant (εr) diminishes from 145 to52 whereas the quality factor (Qxf) will increases from 8105 to 24305 GHz and temperature coefficient of resonant frequencydecreases from 705 to 80 ppm/oC (at 3 GHz).
AHMED SHERAZ,카즈미 와자하트 와히드,Hussain Amjad,Khan Muhammad Zubair,Bibi Saira,Saleem Mohsin,송락현,Sajid Zaman,Ullah Abid,Muhammad Kashif Khan 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.2
Herein, we report a facilely synthesized Sm0.5Sr0.5CoO3 (SSC) nano-catalyst as a cathode material for the solid oxide fuel cell (SOFC). The SSC nano-catalyst was synthesized by a sol–gel process using citric acid and metal nitrates and calcination was performed at a relatively low temperature of 1250 ℃. The crystallinity and morphology of the catalyst were observed by the X-ray diffraction and scanning electron microscope. The average particle size of the SSC powder was 100 nm after calcination at 1250 °C. The resulting SSC material was employed as a cathode for the SOFC. The SOFC cell with highly active SSC showed a peak power density of 900 mWcm−2 at 700 °C. The single cell with an SSC cathode showed excellent stability under the accelerated operating conditions of 0.5A/cm2 and 650 °C for 1250 min. The cell performance was enhanced during the initial hours of the long-term operation which is attributed to the cathode activation process and improved cathode/buffer layer interface contact. This work features a cost-effective, scalable, and reproducible method for the production of highly robust SSC cathode material for the SOFC under relatively low calcination temperatures.