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1.
A new method for thickness determination of single-crystal thin samples at exact zone axis orientation, based on pattern recognition in convergent beam electron diffraction (CBED), is presented. The method is especially well suited to materials with a large unit cell in zone axis directions where the reciprocal lattice is uniformly dense with diffraction points. The new method is based on comparison of a measured CBED zone axis pattern with a set of calculated ones. Its accuracy was estimated to be around 10% in the 5–100 nm thickness range as checked for garnets at the [111] zone orientation.  相似文献   

2.
This paper we proposed a quantum pattern search algorithm based on Grover’s algorithm with closed match. Compared to QuAM proposed by Dan Ventura and QuAM with distributed queries proposed by Ezhov, our algorithm could not only resolve completion problem but also retrieved the full information of the query pattern which only known partial information with non-negligible probability. The algorithm took advantage of the encoding for the pattern set. Moreover we transformed the encoding of each pattern in set to encode all the pattern match cases in order to reduce the cost of encoding. Thus, the nontrivial initial state brought a new method to realize quantum pattern search with a series of proper unitary operations. The simulation result of experiments was also proved that our algorithm was useful and efficient.  相似文献   

3.
多模式融合下的海洋溢油高光谱成像油种识别方法   总被引:1,自引:1,他引:0  
为利用不同油种的发光特性来探测海洋溢油,通过高光谱成像仪,在两种照明模式下采集了6种溢油油种的高光谱图像。基于33个波段构建了波段均值、波段差、波段比和归一化波段比4个辐射指数,提出了基于Fisher和PCA的模型共识的溢油高光谱特征选择方法,采用RBF-SVM模型对油种进行识别。比较发现,本文构建的基于光源混合、波段运算和模型共识的多模式融合方法,从不同侧面提高了模型的溢油识别能力,识别率达到了99.1%以上,比单一方法提高了10%以上。结果表明,多模式融合有效提高了海洋溢油的识别率。  相似文献   

4.
基于六粒子纠缠态和Bell态测量的量子信息分离   总被引:2,自引:2,他引:0  
通过介绍六粒子纠缠态的新应用研究,提出了一个二粒子任意态的信息分离方案.在这个方案中,发送者Alice、控制者Charlie和接受者Bob共享一个六粒子纠缠态,发送者先执行两次Bell基测量;然后控制者执行一次Bell基测量;最后接受者根据发送者和控制者的测量结果,对自己拥有的粒子做适当的幺正变换,从而能够重建要发送的...  相似文献   

5.
We propose a scheme for teleporting a single qubit state employing a unique three-particle W state as quantum channel. By adopting QED cavity technologies, our scheme does not involve the Bell-state measurements(BMs). An unknown state a|0〉 + b|1〉 can be probabilistically teleported by communicators' single particle measurements, unitary operations and classical communications. We can perfectly teleport quantum state ½1√2(|0〉 +|1〉) with 100% probability.  相似文献   

6.
Shapiro JH  Wong FN 《Optics letters》2007,32(18):2698-2700
We describe a method for generating single photons on demand by means of a modular array of spontaneous parametric downconverters that are mediated by electro-optic polarization controls. Our scheme allows easy addition of downconverter modules to improve single-photon generation performance while simultaneously further suppressing multiphoton events. We estimate that a single-photon generation probability of over 60% per pulse with a multiphoton probability of 1% is achievable with currently available technology. This on-demand source may significantly improve the performance of quantum key distribution, quantum communication, and quantum computation systems.  相似文献   

7.
Vowels in checked syllables are almost short and abrupt in Chinese Mandarin dialects. This paper proposed a parametric statistical modeling for the analysis of these vowels.The parameters were described empirically with the method of probability distribution. The effects of the multiparameter classifications were estimated by the binary and multinomial logistic models, and the method of support vector machine was adopted to carry out the pattern recognition of the classifications. The results show that the parameters of duration, DCT_(1-3)are significant to the external classification, and the parameters of DCT_(0-3) have significant main effects on the internal classification. The automatic testing shows that the hit rate of the external pattern recognition is only 43.6% but the rate is 96.1% of the internal. It indicates that the abrupt feature should be additive rather than distinctive.  相似文献   

8.
A new application of the genuinely entangled five-qubit state is investigated for quantum information splitting of a particular type of two-qubit state. In this scheme, a genuinely entangled five-qubit state is shared by Alice (a sender), Charlie (a controller) and Bob (a receiver), and Alice only needs to perform two Bell-state measurements and Charlie performs a single-qubit measurement, Bob can reconstruct the two-qubit state by performing some appropriately unitary transformations on his qubits after he knows the measured results of both Alice and Charlie. This quantum information splitting scheme is deterministic, i.e. the probability of success is 100 %. The presented protocol is showed to be secure against certain eavesdropping attacks.  相似文献   

9.
木材的种类识别是木材加工和贸易的一个重要环节,传统的木材种类识别方法主要有显微检测法和木材纹理识别法,其操作繁琐,耗时长,成本高,不能满足当前需求。本研究利用木材的近红外光谱(NIRS)结合模式识别方法,以期实现木材种类的快速准确识别。采用近红外光谱结合主成分分析法(PCA)、偏最小二乘判别分析法(PLSDA)和簇类独立软模式法(SIMCA)三种模式识别对58种木材进行种类鉴别研究;5点平滑、标准正态变量变换(SNV)、多元散射校正(MSC)、Savitzky-Golay一阶导数(SG 1st-Der)和小波导数(WD)五种光谱预处理方法用于木材光谱的预处理;校正集和测试集样品的正确识别率(CRR)用于模型的评价。采用PCA方法,通过样品的前三个主成分空间分布图分辨木材种类的聚类情况。在建立PLSDA模型,原始光谱的正确识别率最高,分别为88.2%和88.2%;5点平滑处理的光谱校正集和测试集的CRR分别为88.1%和88.2%;SNV处理的光谱校正集和测试集的CRR分别为84.4%和84.5%;MSC处理的光谱校正集和测试集的CRR分别为83.1%和84.2%;SG 1st-Der处理的光谱校正集和测试集的CRR分别为81.8%和82.7%;WD(小波基为“Haar”,分解尺度为80)处理的光谱校正集和测试集的CRR分别为87.3%和87.2%。可知,在PLSDA模型中,木材光谱未经预处理种类识别效果最后好。在建立SIMCA模型过程中,原始光谱的校正集和测试集的CRR分别为99.7%和99.4%;5点平滑处理的光谱校正集和测试集的CRR分别为100%和100%;SNV处理的光谱校正集和测试集的CRR分别为99.5%和99.1%;MSC处理的光谱校正集和测试集的CRR分别为99.0%和98.4%;SG 1st-Der的光谱校正集和测试集的CRR分别为81.8%和82.7%;WD处理的光谱校正集和测试集的CRR分别为100%和100%。可知,在SIMCA模型中,木材光谱经平滑和小波导数处理后的识别效果最好,且光谱的校正集和测试集CRR都为100%。采用三种模式结合五种不同的预处理方法对木材近红外光谱进行定性建模识别时,由于木材样本属性复杂,主成分分布图相互交织,PCA无法识别出58种木材;原始光谱的PLSDA模型可以得到较好的判别模型,但校正集和测试集的CRR只有88.2%和88.2%;木材光谱经过5点平滑或WD预处理后的SIMCA模型可达到最好的识别效果,校正集和测试集的CRR均为100%,且WD-SIMCA模型因子数比5点平滑SIMCA模型小,模型更为简化,故WD-SIMCA为58种木材种类识别的最优模型。研究表明光谱预处理方法可以有效的提高木材种类识别精度,有监督模式识别方法SIMCA可以用来建立有效的木材识别模型,近红外光谱结合模式识别可以为木材种类的识别提供一种快速简便的分析方法。  相似文献   

10.
玉米品种近红外光谱的特征分析与鉴别方法   总被引:1,自引:0,他引:1  
以玉米种子的4 000~12 000 cm-1波段的漫反射近红外光谱为研究对象,提出了一种鉴别玉米品种的新方法。采用主成分分析法(PCA)来研究数据特征,发现近红外光谱在特征空间中具有显著的长条状分布特征,为此我们研究了改变样本点在PCA空间中的分布对品种鉴别的影响,并提出了归一化主成分分析(NPCA)的特征提取算法,同时还根据近红外光谱的数据分布特点提出了一种主方向仿生模式识别的分类算法,进一步提高了鉴别正确率。鉴别模型对第一测试集的平均正确识别率达到了97.67%,平均正确拒识率达到了98.40%,30个品种中的13个达到了100%的正确识别率;对第二测试集的平均正确拒识率达到了98.90%,有11个品种达到了100%的正确拒识率,具有较高的鉴别准确度。  相似文献   

11.
The ability to simulate and control complex physical situations in real time is an important element of many engineering and robotics applications, including pattern recognition and image classification. One of the ways to meet specific requirements of a process is a reduction of computational complexity of algorithms. In this work we propose a new coding of binary pattern units (BPU) that reduces the time and spatial complexity of algorithms of image classification significantly. We apply this coding to a particular but important case of the coordinated clusters representation (CCR) of images. This algorithm reduces the dimension of the CCR feature space and, as a consequence, the time and space complexity of the CCR based methods of image classification, exponentially. In addition, the new coding preserves all the fundamental properties of the CCR that are successfully used in the recognition, classification and segmentation of texture images. The same approach to the coding of BPUs can be used in the Local Binary Pattern (LBP) method. In order to evaluate the reduction of time and space complexity, we did an experiment on multiclass classification of images using the “traditional” and the new coding of the CCR. This test showed very effective reduction of the computing time and required computer memory with the use of the new coding of BPUs of the CCR, retaining 100% or a little less efficiency of classification at the time.  相似文献   

12.
庞朝阳  周正威  郭光灿 《中国物理》2006,15(12):3039-3043
Many classical encoding algorithms of vector quantization (VQ) of image compression that can obtain global optimal solution have computational complexity O(N). A pure quantum VQ encoding algorithm with probability of success near 100% has been proposed, that performs operations 45\sqrt{N} times approximately. In this paper, a hybrid quantum VQ encoding algorithm between the classical method and the quantum algorithm is presented. The number of its operations is less than \sqrt{N} for most images, and it is more efficient than the pure quantum algorithm.  相似文献   

13.
A new method is proposed for ab initio calculations of nonstationary quantum processes on the basis of a probability representation of quantum mechanics with the help of a positive definite function (quantum tomogram). The essence of the method is that an ensemble of trajectories associated with the characteristics of the evolution equation for the quantum tomogram is considered in the space where the quantum tomogram is defined. The method is applied for detailed analysis of transient tunneling of a wave packet. The results are in good agreement with the exact numerical solution to the Schrödinger equation for this system. The probability density distributions are obtained in the coordinate and momentum spaces at consecutive instances. For transient tunneling of a wave packet, the probability of penetration behind the barrier and the time of tunneling are calculated as functions of the initial energy.  相似文献   

14.
As an important communication technology, quantum information transmission plays an important role in the future network communication. It involves two kinds of transmission ways: quantum teleportation and remote state preparation. In this paper, we put forward a new scheme for optimal joint remote state preparation (JRSP) of an arbitrary equatorial two-qudit state with hybrid dimensions. Moreover, the receiver can reconstruct the target state with 100 % success probability in a deterministic manner via two spatially separated senders. Based on it, we can extend it to joint remote preparation of arbitrary equatorial multi-qudit states with hybrid dimensions using the same strategy.  相似文献   

15.
针对252Cf源驱动噪声分析测量法中核材料浓度识别问题,采用压缩感知理论,在K最近邻(KNN)识别算法基础上,研究了一种基于压缩采样的K最近邻(CSKNN)分类识别方法,进而研究并分析了CSKNN方法的识别概率。实验结果表明,CSKNN分类识别方法只需少量的观测值(观测比M/N≥0.1),即可达到分类识别的目的;当信噪比提高时,识别概率将会以更快的速度收敛至100%,且对K值的敏感程度也会随之降低。这样,不仅提高了核军控核查的实时性,而且还有效降低了采样成本,为核材料浓度的在线判读提供了一种新的理论基础和实现方法。  相似文献   

16.
针对目前普通光电成像系统对伪装目标的探测和识别概率较低的状况,提出伪装目标的探测识别新技术研究。介绍了红外偏振成像系统的原理、组成和特点,研制的中波/长波红外偏振成像装置,其波段范围为3 m ~5 m和8 m~12 m,线偏振度95%,消光比大于100∶1,给出了试验分析数据和偏振融合效果图。研究表明,采用红外偏振成像技术可以有效地实现对地面伪装目标的探测和识别。研究结果还可以扩展到对人工假目标、空中隐身目标等的探测和识别。  相似文献   

17.
本文提出了一个基于SQUIDs和腔场的大失谐相互作用传送量子信息的方案,此方案可以直接地、百分之百地实现量子信息的传送.该方案中腔场和SQUIDs系统之间没有量子信息的传递,腔场只是虚激发,这样对腔的品质因子的要求大大的降低了.同时也可以在SQUIDs之间建立传送量子信息的量子网络.  相似文献   

18.
Moncy V. John 《Annals of Physics》2010,325(10):2132-2139
It is shown that a normalisable probability density can be defined for the entire complex plane in the modified de Broglie-Bohm quantum mechanics, which gives complex quantum trajectories. This work is in continuation of a previous one that defined a conserved probability for most of the regions in the complex space in terms of a trajectory integral, indicating a dynamical origin of quantum probability. There it was also shown that the quantum trajectories obtained are the same characteristic curves that propagate information about the conserved probability density. Though the probability density we now adopt for those regions left out in the previous work is not conserved locally, the net source of probability for such regions is seen to be zero in the example considered, allowing to make the total probability conserved. The new combined probability density agrees with the Born’s probability everywhere on the real line, as required. A major fall out of the present scheme is that it explains why in the classical limit the imaginary parts of trajectories are not observed even indirectly and particles are confined close to the real line.  相似文献   

19.
本文提出了一个基于SQUIDs和腔场的大失谐相互作用传送量子信息的方案,此方案可以直接地、百分之百地实现量子信息的传送。该方案中腔场和SQUIDs系统之间没有量子信息的传递,腔场只是虚激发, 这样对腔的品质因子的要求大大的降低了。同时也可以在SQUIDs之间建立传送量子信息的量子网络。  相似文献   

20.
As a special quantum node in a quantum network, the quantum router plays an important role in storing and transferring quantum information. In this paper, we propose a quantum router scheme based on asymmetric intercavity couplings and a three-level Λ-type atomic system. This scheme implements the quantum routing capability very well. It can perfectly transfer quantum information from one quantum channel to another. Compared with the previous quantum routing scheme, our proposed scheme can achieve the transfer rate of single photons from one quantum channel to another quantum channel reaching 100%, the high transfer rate is located in the almost quadrant regions with negative values of the two variables λ_a and λ_b, and their maximum values T_u~b+T_d~b= 1 emerge in the center point λ_a=λ_b=-1. Therefore, it is possibly feasible to efficiently enhance the routing capability of the single photons between two channels by adjusting the inter-resonator couplings, and the asymmetric intercavity coupling provides a new method for achieving high-fidelity quantum routers.  相似文献   

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