3,308 research outputs found
Experimental Realization of Br\"{u}schweiler's exponentially fast search algorithm in a homo-nuclear system
Compared with classical search algorithms, Grover quantum algorithm [ Phys.
Rev. Lett., 79, 325(1997)] achieves quadratic speedup and Bruschweiler hybrid
quantum algorithm [Phys. Rev. Lett., 85, 4815(2000)] achieves an exponential
speedup. In this paper, we report the experimental realization of the
Bruschweiler$ algorithm in a 3-qubit NMR ensemble system. The pulse sequences
are used for the algorithms and the measurement method used here is improved on
that used by Bruschweiler, namely, instead of quantitatively measuring the spin
projection of the ancilla bit, we utilize the shape of the ancilla bit
spectrum. By simply judging the downwardness or upwardness of the corresponding
peaks in an ancilla bit spectrum, the bit value of the marked state can be read
out, especially, the geometric nature of this read-out can make the results
more robust against errors.Comment: 10 pages and 3 figure
Active backstepping control of combined projective synchronization among different nonlinear systems
In this article, the authors have studied combination projective synchronization using active backstepping method. The main contribution of this effort is realization of the projective
synchronization between two drive systems and one response system. We relax some limitations of previous work, where only combination complete synchronization has been investigated. According to Lyapunov stability theory and active backstepping design method, the corresponding controllers are designed to observe combination projective synchronization among three different classical chaotic systems, i.e. the Lorenz system, Rossler system and € Chen system. The numerical simulation examples verify the effectiveness of the theoretical analysis. Combination projective synchronization has stronger anti-attack ability and antitranslated ability than the normal projective synchronization scheme realized by one drive and one response system in secure communication
Clinical and pathological analysis of 504 cases of elderly ocular tumors
AIM:To analyze the composition, distribution and characteristics of the elderly primary ocular tumors. <p>METHODS: This was a retrospective study and all 504 cases with primary ocular tumors aged 60 years or older were collected in Shanxi Eye Hospital, during the year 2000-2012. The onset age, location and pathological pattern were analyzed.<p>RESULTS: There were 346 cases of benign ocular tumors(68.7%), and 158 cases of malignancy(31.3%).Papillomas was the most common type of the benign with 83 cases(16.5%), followed by a variety of inflammatory cysts and lesions with 69 cases(13.7%)and 64 cases(12.7%)respectively. Among malignant tumors cases, eyelid basal cell carcinoma originated from epithelial was the most common with 72 cases(14.3%), followed by skin appendages sources malignant tumors with 39 cases(7.7%). Concerning the location of ocular tumors, there were 282 cases of eyelid tumor(56.0%)occupied the first position followed by conjunctival tumor with 157 cases(31.2%). <p>CONCLUSION: The prevalence and type of primary ocular tumor in elderly people are significant differences from the general population and children's, and the proportion of malignant tumors tended to increase along with the increase of age
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