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Image compressors improve the handling of image data in image-processing systems. In our proposed image-compression system, we employ a smart complementary metal oxide semiconductor (CMOS) sensor and an integrated spatial light modulator (SLM) and then the optoelectronic architecture performs a large part of image-compression processes. Each pixel of the integrated SLM consists of multiple modulation pads; the integrated SLM then performs decoding and optical D/A conversion. A paired configuration of the smart CMOS sensor and the integrated SLM transforms optical analog signals into electronic digital signals. A theoretical analysis showed that the error ratio of the proposed systems was 3%.  相似文献   
995.
Potassium lithium niobate (KLN) fiber crystals have been grown by μ-pulling down method. The KLN fibers doubled around 806 nm radiation for type I noncritical phase matching at room temperature. We observed ~0.6 mW output power from single-pass second harmonic generation at an input power of 700 mW.  相似文献   
996.
A sharp interface problem arising in the flow of two immiscible fluids, slag and molten metal in a blast furnace, is formulated using a two-dimensional model and solved numerically. This problem is a transient two-phase free or moving boundary problem, the slag surface and the slag–metal interface being the free boundaries. At each time step the hydraulic potential of each fluid satisfies the Laplace equation which is solved by the finite element method. The ordinary differential equations determining the motion of the free boundaries are treated using an implicit time-stepping scheme. The systems of linear equations obtained by discretization of the Laplace equations and the equations of motion of the free boundaries are incorporated into a large system of linear equations. At each time step the hydraulic potential in the interior domain and its derivatives on the free boundaries are obtained simultaneously by solving this linear system of equations. In addition, this solution directly gives the shape of the free boundaries at the next time step. The implicit scheme mentioned above enables us to get the solution without handling normal derivatives, which results in a good numerical solution of the present problem. A numerical example that simulates the flow in a blast furnace is given.  相似文献   
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A gas-liquid chromatographic method for the determination of peptido-aminobenzophenone (2-o-chlorobenzoyl-4-chloro-N-methyl-N'-glycyl-glycinanilide, I) in dog plasma was developed. Decomposition of compound I was observed during chromatography. In alkaline medium, compound I in plasma was submitted to ring closure to yield 3-amino-6-chloro-5-(2-chlorophenyl)-1-methylquinolin-2-one (aminoquinolone), and the hexane extract was assayed by gas-liquid chromatography using electron-capture detection. The concentration range of compound I studied was 10--90 ng per 0.5 ml of plasma. Interference from both endogenous and exogenous sources was negligible. The method could be applied to the determination of the plasma level of compound I in dogs following oral administration of a single 5 mg/kg dose.  相似文献   
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The excitation of the unnatural parity state (2?, 8.87 MeV) of 16O by inelastic scattering of 40 MeV α particle is investigated microscopically. The two step excitation mechanism via the 3? state at 6.13 MeV is found to reproduce the magnitude of the measured cross section of the 2- excitation. The α-nucleon interaction used for the 2- excitation also reproduces the 3- excitation.  相似文献   
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