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41.
In this scheme, two quantum oscillators in a planar radio frequency ion trap are coupled by the trap electrodes. The ions motional states encode the quantum bits (qubits), and a swap gate could be achieved. Under different conditions of the experiments, the intensity of the coupling between two quantum oscillators and the dissipation of the system are calculated. We compute fidelities for a quantum swap gate and discuss experimental issues. 相似文献
42.
江苏淤泥质海岸入海河道闸下淤积研究 总被引:1,自引:0,他引:1
通过建立ARIMA模型,分析了江苏淤泥质海岸四条入海河道(射阳河、新洋港、斗龙港和黄沙港)建闸后闸下河道的冲淤演变过程,预测闸下河道淤积量的变化情况。结果表明,射阳河闸下淤积量将会持续增加,到2010年预计量可达2.47×107m3,淤积量为四条河中最大;黄沙港和斗龙港有波动上升的趋势,但无射阳河明显,淤积量有小幅度增加;新洋港变化不大,已达到冲淤平衡的状态。 相似文献
43.
一种自动多普勒雷达速度退模糊算法研究 总被引:5,自引:0,他引:5
提出了一种能解决孤立风暴、高切变和强台风等情况下速度模糊问题的自动多普勒雷达速度退模糊算法。该算法首先通过搜索最弱风区,第一次确定的最多两组初始参考径向和参考速度库,其中使用了相邻仰角初始参考径向应具有方位连续性的约束条件,剔除假零速度线引起的不恰当备用初始径向;然后从初始参考径向和参考速度库开始,对其周围邻近的速度库进行连续性检查,如果当前库的径向速度与参考速度的差值大于给定阈值就对其进行纠正;完成两次全方位径向退模糊处理后,算法进行径向和方位方向的强风切变检查,如果还有强风切变存在,那么通过搜索弱风切变区中有效速度库最多的径向,第二次确定一组退模糊的初始参考径向和参考速度库,再重复前面的退模糊过程,这有利于远离雷达的孤立风暴的速度退模糊。在多次退模糊过程中,判断速度模糊的标准由紧到松,切变阈值由小到大,以确保用于后面退模糊处理的参考速度的可靠性。利用我国S波段多普勒天气雷达观测的龙卷、飑线、孤立强风暴及台风等事件的1 000多个体扫资料对该算法进行了测试和评估,结果表明,速度退模糊准确率>99.5%。对于孤立风暴、高切变及强台风等复杂情况下的速度退模糊来说,新算法要优于我国新一代天气雷达业务退模糊方案。 相似文献
44.
45.
We consider a flap gate farm, i.e. a series of P arrays, each made of Q neighbouring flap gates, in an open sea of constant depth, forced by monochromatic incident waves. The effect of the gate thickness on the dynamics of the system is taken into account. By means of Green's theorem a system of hypersingular integral equations for the velocity potential in the fluid domain is solved in terms of Legendre polynomials. We show that synchronous excitation of the natural frequencies of Sammarco et al. (2013) yields large amplitude response of gate motion. This aspect is fundamental for the optimisation of the gate farm for energy production. 相似文献
46.
介绍了一个以AT89S52单片机为主要处理单元,配合存储电路、复位电路以及其它元器件实现门禁地址的分配及存储判定的门禁控制电路,该控制器通过对串口数据的处理,能实时对PC进行通信并通过实时代码验证各项控制器操作. 相似文献
47.
Abstract A procedure to identify sets of operational rules for gated spillways for optimal flood routing management of artificial reservoirs is proposed. The flood retention storage of a dam having a gated flood spillway is divided into 15 sub-storages whose surface elevations are identified as critical levels. The most suitable operation set for the downstream conditions and for the dam can be chosen from many derived operation sets. The spillway gates are operated in an optimum way for any floods from very small magnitudes to the probable maximum flood (PMF), without having to forecast the actual magnitude of the incoming flood hydrograph. Decision floods are formed by dividing the PMF into 15 sub-hydrographs by 5 and 10% increments in the ranges 5–50% and 50–100% of the PMF, respectively. Many potential spillway gate openings from closed to fully open are chosen initially. As a result of a series of routing simulations of 15 decision floods, a set of 15 gate openings is determined such that all floods from very small magnitudes to the PMF may be routed without overtopping the dam crest. Next, a few more 15-stage operation rules are determined such that the gate openings of the initial stages are decreased as their critical levels are increased stepwise, with the objective of attenuating smaller floods more effectively and releasing higher outflows for larger floods close to and including the PMF. The developed model is applied to the Catalan and Aslantas dams in Turkey, both of which serve for flood mitigation as well as hydropower generation. Citation Haktanir, T., Citakoglu, H., and Acanal, N., 2013. Fifteen-stage operation of gated spillways for flood routing management through artificial reservoirs. Hydrological Sciences Journal, 58 (5), 1013–1031. Editor Z.W. Kundzewicz; Associate editor A. Montanari 相似文献
48.
Abstract A one-dimensional water quantity and quality mathematical model was developed to evaluate the effects of joint gate–pump operation in terms of water withdrawal for pollutant flushing. The study was carried out in dry seasons in the Foshan River channel, China. The results indicate that the input of freshwater into the upper and middle reaches of the Foshan River can improve the water quality of the lower reaches. However, the backwater effect due to water diversion in the middle reaches of the river can greatly offset the cleaning processes in the upper reaches of the Foshan River. The results indicate that water quality in the upper Foshan River (Jiebian) may degrade with an increase in the rate of water withdrawal from the middle river when the discharge pumped from the upper Foshan River is less than 10m3/s; optimal water quality improvement is obtained with discharge values of 30 and 20 m3/s, respectively, at the upper and middle reaches of the Foshan River. Editor D. Koutsoyiannis Citation Liu, C.-L., Jiang, T., Zhang, Q., Zhu, S. and Li, K., 2012. Modelling of water withdrawal for pollutant flushing in the tidal river network, Pearl River Delta, China. Hydrological Sciences Journal, 57 (3), 576–590. 相似文献
49.
张永军 《沙漠与绿洲气象(新疆气象)》2001,24(5):33-34
介绍铁路大风监测系统的数据库管理,包含大风监测系统数据库的几个模块的主要劝能讲述(并给出了部分程序)、数据库模块运行机制简介和实际应用。 相似文献
50.
基于Windows NT服务器的前兆数据共享及其实现 总被引:3,自引:2,他引:3
简要介绍了地震前兆数据的现状及其实现数据共享的必要性;分析了常用的二种通用Web数据库的体系结构及应用技术,它们是基于通用网关接口CGI的体系结构和基于服务器扩展API的体系结构。考虑到前兆台网中心硬件设备的条件、所运行的数据库平台和地震前兆数据的复杂性和多样性特点,前兆数据在Internet上的共享服务采用基于通用网关接口CGI的体系结构编写应用程序来实现。以WWW服务器为平台,通过Web服务器方式在浏览器上实现共享,可检索任意台站、任意观测方法、任意地点、任意时段的前兆数据,实现地震前兆数据信息网络服务功能。 相似文献