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31.
Employing a polarization-entangled \(\chi \) state, which is a four-photon genuine entangled state, we propose a protocol teleporting a general two-photon polarization state. Firstly, the sender needs to perform one Controlled-NOT gate, one Hadamard gate, and one Controlled-NOT gate on the state to be teleported in succession. Secondly, the sender performs local nondemolition parity analyses based on cross-Kerr nonlinearities and publicizes the achieved outcomes. Finally, conditioned on the sender’s analysis outcomes, the receiver executes the single-photon unitary transformation operations on his own photons to obtain the state originally sit in the sender’s location. Due to the employment of nondemolition parity analyses rather than four-qubit joint measurement, it can be realized more feasible with currently available technologies. Moreover, the resources of Bell states can be achieved because the nondestructive measurement is exploited, which facilitates other potential tasks of quantum information processing.  相似文献   
32.
A scheme is proposed to generate three-atom GHZ states by applying the inversely engineered control method on the basis of Lewis–Riesenfeld invariants. In the proposal, three atoms that have different configurations are trapped in a bimodal cavity. Numerical simulations indicate that our protocol has an obvious improvement of speed for the generation of GHZ states. Moreover, the present scheme is robust against both parameter fluctuations and dissipation.  相似文献   
33.
本文介绍了××餐饮管理服务有限公司酒店对网络运营管理服务信息系统的开发过程,包括软件工程的需求分析、系统功能结构设计、数据库设计以及调试在内的所有开发过程。本文中所论述的网络运营管理服务信息系统是一个将业务处理从纯人工操作转换成人工与计算机共同处理的一个实例,并对转换过程进行了详细策划,可作为同类计算机网络运营管理服务信息系统的应用参考。  相似文献   
34.
针对人们对前景图像比较敏感的特性,提出了一种加强前景信息并弱化背景信息的新方法.该方法首先通过图像的阈值得到前景图像与背景图像,利用某个值加强前景并弱化背景,结合原始图像提取纹理特征,从而进行图像检索.对真实图像数据库的检索实验表明,该方法与其他基于纹理的方法相比,具有较好的检索效果和性能.  相似文献   
35.
介绍了一款新型的高精度、低功耗超声波热能表.此表利用了超声波的测量原理,结合TDC-GP2时间转换芯片,搭配简单的电路,外接超声波换能器、温度传感器,完成了一个热能表的所有功能.  相似文献   
36.
PE管道热熔对接焊的工艺参数随管道尺度和环境条件的不同而不同,同时还受人为因素的影响,对焊接机自动化程度要求很高.介绍了基于ARM嵌入式热熔焊接机智能控制器的硬件和软件的设计方案.此方案符合焊接各个阶段工艺参数指标,并具有操作纠错及错误信息管理功能,最大程度地消除了人为因素的影响,提高焊接质量,并具备焊接数据的可追溯性,便于管理人员对焊接工程的管理.  相似文献   
37.
Ventilated packaging is widely used in the forced‐air precooling practice for horticultural produce. Fresh fruits are living organisms which are sensitive to temperature in turn related to airflow and heat transfer inside package. In this study, a transient mathematical model considering heat of respiration and evaporation is developed to predict the thermal response of tray‐layered fruits in ventilated packages during forced‐air precooling. Specifically, the heat source is combined with the energy conservation equation and loaded into numerical solution by User Defined Function (UDF). Temperature profiles of three variously distributed circular and oblong vents in three different patterns (spaced, paralleled and crossed stacking) are simulated, separately. The results show that the heat source affects fruit cooling process, and the layered fruit in paralleled stacking pattern tends to be cooled better than others. Furthermore, the results indicate that vertical oblong vent could improve the longitudinal and lateral airflow, while non‐central vent design could greatly improve the overall cooling performance. Definitely a triangular distribution of three circular vents was superior to laterally distributed centre vents with 66.5% higher uniformity and 2.5°C lower of the highest temperature. Compared with the three identical vertical oblong vent conditions, vent design with one hand hole and two side vertical oblong vents can be cooled more uniformly with an increase of 6.5%. It is revealed that vents with large major‐to‐minor axis ratio could be applied to balance airflow and ease cooling differences for a rapid but uniform cooling. Experimental validations were performed for Sim2, Sim4 and Sim6, Sim8, Sim9, and good agreement was obtained considering the five vent conditions with the error less than 3.5°C but coordinated later (within the limits of the experimental uncertainty).Thus the numerical model can be used to predict and optimize temperature distribution within precooling packages. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
38.
交互性在提升电商网站用户忠诚中的应用策略分析   总被引:1,自引:1,他引:0  
苗秀  韩冬楠  王腾 《包装工程》2016,37(12):143-148
目的对电商网站的交互性进行分析。方法通过文献调研划分交互行为,在竞品分析和深度访谈等定性研究的基础上,编撰调查问卷并开展大规模调查,回收定量数据,结合电商网站的特性,运用SPSS主成分分析法对交互因子进行提取研究。结论电商网站的交互因子可以概括为相关性、真实性和关系性3个方向,从信息交互和社会交互两个维度有针对性地探索各交互因子的应用策略,可以有效提升电商网站的用户忠诚。  相似文献   
39.
Identification of atomic disorders and their subsequent control has proven to be a key issue in predicting, understanding, and enhancing the properties of newly emerging topological insulator materials. Here, we demonstrate direct evidence of the cation antisites in single-crystal SnBi2Te4 nanoplates grown by chemical vapor deposition, through a combination of sub-ångström-resolution imaging, quantitative image simulations, and density functional theory calculations. The results of these combined techniques revealed a recognizable amount of cation antisites between Bi and Sn, and energetic calculations revealed that such cation antisites have a low formation energy. The impact of the cation antisites was also investigated by electronic structure calculations together with transport measurement. The topological surface properties of the nanoplates were further probed by angle-dependent magnetotransport, and from the results, we observed a two-dimensional weak antilocalization effect associated with surface carriers. Our approach provides a pathway to identify the antisite defects in ternary chalcogenides and the application potential of SnBi2Te4 nanostructures in next-generation electronic and spintronic devices.
  相似文献   
40.
In this article, a novel single negative metamaterial (MTM) transmission line (TL) consisting of a Hilbert‐shaped complementary ring resonator (H‐CRR) on the ground plane is initially presented and studied in depth. Then based on the proposed MTM TL, a novel six‐section Hi‐Lo microstrip low‐pass filter (LPF) with a cut‐off frequency 2.5 GHz is developed, fabricated, and measured. Measurement results indicate that: by integrating H‐CRR, the selectivity has been significantly improved which is 77.3 dB/GHz due to the single negative permittivity; by etching a crown square on low‐impedance section, the bandwidth characterized by 20 dB return loss was obviously enhanced by 26.2% and the maximal sidelobe level of in‐band return loss was reduced from 22 to 24.6 dB. What' more, the developed LPF achieved a 36.3% size reduction with respect to its conventional counterpart. The design concept, which was confirmed by the measurement data, is of practical value and can be popularized in other microwave devices where high selectivity is requested. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   
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