Broadband near-infrared (NIR) phosphors converted light-emitting diodes (pc-LEDs) have attracted tremendous attention for their great potential in NIR spectroscopy applications. Herein, we report on the photoluminescence (PL) properties of Cr 3+ -doped Sc(PO 3 ) 3 , which exhibits a broadband NIR emission centered at 900 nm with a full width at half-maximum (FWHM) of 161 nm upon excitation at 480 nm. In terms of the examination of spectroscopic parameters, we find that Cr 3+ ions occupy a weak crystal field site (Dq/B = 1.94) in the Sc(PO 3 ) 3 host with a stronger electron-phonon coupling (Huang-Rhys factor, S = 5.5), which results in a serious thermal quenching and a low internal quantum efficiency (IQE). Thermal stability and IQE of phosphors can be substantially enhanced by the introduction of Yb 3+ ions. In the light of the analysis of excited-state dynamics, we demonstrate that the enhancement mechanism is ascribed to the efficient Cr 3+ →Yb 3+ energy transfer from the thermal sensitive Cr 3+ centers to the thermal stable Yb 3+ emitters. An NIR pc-LED device has been finally fabricated by the combination of a blue-emitting chip and a Cr 3+ /Yb 3+ codoped Sc(PO 3 ) 3 phosphor whose potential application for broadband NIR pc-LEDs is also discussed. K E Y W O R D Sbroadband near-infrared, Cr 3+ , energy transfer, phosphor-converted LED, Sc(PO 3 ) 3

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In this paper, a full PMOS Colpitts quadrature voltage-controlled oscillator (QVCO) topology, suitable for low supply voltage and low power dissipation, is presented. For an enhanced voltage swing under a low supply voltage, the capacitive-feedback technique is employed. Quadrature coupling is achieved by employing direct bulk coupling technique, leading to reduction in both power and chip area. The proposed QVCO covers a 5% tuning range between 2.325 GHz and 2.435 GHz, and the phase noise is [Formula: see text]128.2 dBc/Hz at 1-MHz offset from the 2.34-GHz carrier while consuming only 0.535 mW from 0.55-V supply voltage, yielding a figure-of-merit (FoM) of 198 dBc/Hz.

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Rough sets theory provides a good method for getting excellent decision rules set with the conduct of reduction from the decision table. This paper describes many evaluation metrics of decision rules, analyzes the properties for these evaluation metrics. Then it presents the evaluation metrics for rule set, which globally shows the properties of a rule set. And the evaluation system plays an important role for one try to choose the right decision rules in the research of rough set theory.