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51.
With the introduction of multichannel video programming distributors and different types of video platforms, consumers have more choices of channels and platforms than ever. Specifically, the present study focuses on television and the Internet as video platforms.  相似文献   
52.
In this letter, we propose a data randomization scheme for endurance and interference mitigation of deeply‐scaled multilevel flash memory. We address the relationships between data patterns and the raw bit error rate. An on‐chip pseudorandom generator composed of an address‐based seed location decoder is developed and evaluated with respect to uniformity. Experiments performed with 2x‐nm and 4x‐nm NAND flash memory devices illustrate the effectiveness of our scheme. The results show that the error rate is reduced up to 86% compared to that of a conventional cycling scheme. Accordingly, the endurance phenomenon can be mitigated through analysis of interference that causes tech shrinkage.  相似文献   
53.
54.
Cho YS  Kim HY  Cha JH  Pae AN  Koh HY  Choi JH  Chang MH 《Organic letters》2002,4(12):2025-2028
[reaction: see text] Intramolecular Prins-type reactions of compounds having both functionalities of homoallyl alcohol and acetal moiety are described. The intramolecular Prins cyclizations were performed using indium trichloride in chloroform or 25% aqueous THF. Both 9-oxabicyclo[3.3.1]nonane and 3,9-dioxabicyclo[3.3.1]nonane compounds were successfully obtained in moderate yields.  相似文献   
55.
Low tropospheric wind measurement with Mie Doppler Lidar   总被引:3,自引:0,他引:3  
A double edge Mie Doppler lidar at 1064 nm was developed in Hefei, China in 2005 for low tropospheric wind measurement. Intercomparison experiments with a wind profiler and a wiresonde were held. Intercomparisons of concurrent lidar and other instrument observations show good agreement with expected measurement accuracy. The examples of validated lidar wind profiles obtained during these experiments as well as an example of continuous wind observations are presented. The instrument has demonstrated the capability of atmospheric wind field measurement from 0.2 to 5 km altitude, achieving below 2 m/s accuracy with 1 min averaging and 21.2 m vertical resolution.  相似文献   
56.
This communication is our preliminary announcement and claim for achievement of 85 percent aperture efficiency using a dual reflector antenna. We are aware of no other reflector antenna having such aperture efficiency, and we invite the antenna community to comment, critique, or inform us of equal or better claims. A full report will be forthcoming; this brief note will supply only pertinent highlights.  相似文献   
57.
Beam amplitudes of successive orders diffracted on holographic gratings are calculated and thus nonlinear effects in amplitude, bleached phase and reversal bleached phase holograms are compared. Then values of intermodulation noise are compared for the above three types of Fourier hologram of two circular holes.  相似文献   
58.
Kim D  Cha H 《Optics letters》2005,30(13):1728-1730
Two-channel lidar signals that are composed of total rotational scattering and elastic signals provide good information about aerosol scattering coefficients. We can calculate the aerosol backscattering coefficient and extinction coefficient directly, without making any assumption or calibration. Generally, a high-spectral-resolution lidar is used for aerosol monitoring, but we have designed a new low-spectral-resolution lidar system that contains both kinds of scattering information simultaneously, and we have retrieved the aerosol scattering coefficient. The results show that there is no need to assume any relation between aerosol backscattering and extinction or to consider any wavelength calibration to determine the aerosol scattering coefficient.  相似文献   
59.
A Seifert matrix is a square integral matrix satisfying


To such a matrix and unit complex number there corresponds a signature,


Let denote the set of unit complex numbers with positive imaginary part. We show that is linearly independent, viewed as a set of functions on the set of all Seifert matrices.

If is metabolic, then unless is a root of the Alexander polynomial, . Let denote the set of all unit roots of all Alexander polynomials with positive imaginary part. We show that is linearly independent when viewed as a set of functions on the set of all metabolic Seifert matrices.

To each knot one can associate a Seifert matrix , and induces a knot invariant. Topological applications of our results include a proof that the set of functions is linearly independent on the set of all knots and that the set of two-sided averaged signature functions, , forms a linearly independent set of homomorphisms on the knot concordance group. Also, if is the root of some Alexander polynomial, then there is a slice knot whose signature function is nontrivial only at and . We demonstrate that the results extend to the higher-dimensional setting.

  相似文献   

60.
Large nonlinear phase shifts were generated with femtosecond pulses at 1560 nm through cascaded quadratic interactions in periodically poled MgO-doped LiNbO3. The off-diagonal component of the nonlinear coefficient was utilized for simultaneous quasi phase matching and group-velocity matching. The effective nonlinear refractive index was varied from -2.9 x 10(-14) to +3.3 x 10(-14) cm2/W by tuning the phase-mismatch conditions.  相似文献   
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