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701.
Numerous engineering complexities are simplified using optimization algorithms. In a solar power system, the necessity of the voltage regulator is obvious. To control the regulator existent research works used PI, PID controllers that might have an unwanted transient response. To overcome such drawbacks here, a fresh scheme is proposed for the designing of the adaptive sliding mode (SM) controller of a solar powered LUO converter using optimization algorithms. The PSO (‘Particle Swarm Optimization') is proved to expedite the convergence characteristic for many applications. Here, an ameliorated PSO version is developed. This algorithm is termed the Parameter Improved‐PSO (PIPSO) algorithm. In this algorithm, the parameters, say, inertia weight, social along with cognitive agents is updated in every generation. The Proportional Integrator (PI) controller is used. The gain of this controller is tuned using the PIPSO. This algorithm's objective function is to lessen ISE (‘Integral Squared Error’) of the converter's output voltage. This parameter is picked as the objective function of the optimization algorithm. The proposed PIPSO is established to show better outcomes when contrasted to the traditional PSO concerning tuning a collection of parameters. An analysis is also made to evaluate the effect of usage of the solar panel () in the proposed work. 相似文献
702.
A Princy E Annie Rathnakumari S Masilla Moses Kennedy 《Journal of the American Ceramic Society》2023,106(9):5364-5380
A novel vanadate host Ca2LiMg2V3O12 (CLMV) and the Eu3+-doped samples were synthesized via a solid-state reaction method. The phase formation and the morphological analysis were studied in detail. The Rietveld refinement result shows that the host belongs to cubic space group Ia-3d (230) with lattice parameter, a = 12.3948 Å, V = 1904.23 Å3, and Z = 8. The diffuse reflectance spectroscopy measurement estimated the bandgap of the host and the CLMV:0.05Eu3+ phosphors. The host exhibits a broad absorption band (peak at 345 nm) ranging from 240 to 380 nm, which is attributed to the charge transfer in the O2−–V5+ complex. Under near UV excitation (λexc = 345 nm), the host gives a broad emission band covering the visible region from 400 to 730 nm and the emission is in the bluish–green region of the CIE diagram. When the host is doped with the Eu3+ ions and excited at 345 nm, the emission spectrum depicts the superimposition of the characteristic emission bands (red emission) of the Eu3+ ions corresponding to the f–f transitions over the broad emission band of the host. The calculated color coordinates (9600 to 2280 K) demonstrated the color tuning ability of the phosphor as the dopant concentration is increased in the host. This is because the VO43− group plays the sensitiser role and partially transfers energy with the Eu3+ ions. When the same set of phosphors were excited at the dominant characteristic excitation band (λexc = 394 nm) of the Eu3+, the characteristic emission bands of the Eu3+ in the orange–red region were observed. As the electric dipole transition of the Eu3+ was found to be dominant, the prepared phosphors possessed high color purity (CP). The energy transfer mechanism and the lifetime values were also presented. The temperature-dependent PL studies showed good thermal stability of the optimum sample. Various radiative transition properties were analyzed by the Judd–Ofelt theory. The photometric results reveal the color tuning ability and CP of the CLMV:xEu3+ phosphors. 相似文献
703.
Abraham S. Moses Leena Kadam Anna St Lorenz Maureen K. Baldwin Terry Morgan Jessica Hebert Youngrong Park Hyelim Lee Ananiya A. Demessie Tetiana Korzun Babak Mamnoon Adam W. G. Alani Oleh Taratula Leslie Myatt Olena R. Taratula 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(2):2202343
Ectopic pregnancy (EP) is the leading cause of maternity-related death in the first trimester of pregnancy. Approximately 98% of ectopic implantations occur in the fallopian tube, and expedient management is crucial for preventing hemorrhage and maternal death in the event of tubal rupture. Current ultrasound strategies misdiagnose EP in up to 40% of cases, and the failure rate of methotrexate treatment for confirmed EP exceeds 10%. Here the first theranostic strategy for potential management of EP is reported using a near-infrared naphthalocyanine dye encapsulated within polymeric nanoparticles. These nanoparticles preferentially accumulate in the developing murine placenta within 24 h following systemic administration, and enable visualization of implantation sites at various gestational stages via fluorescence and photoacoustic imaging. These nanoparticles do not traverse the placental barrier to the fetus or impact fetal development. However, excitation of nanoparticles localized in specific placentas with focused NIR light generates heat (>43 °C) sufficient for disruption of placental function, resulting in the demise of targeted fetuses with no effect on adjacent fetuses. This novel approach would enable diagnostic confirmation of EP when current imaging strategies are unsuccessful, and elimination of EP could subsequently be achieved using the same nano-agent to generate localized hyperthermia resulting in targeted placental impairment. 相似文献