基于地形图像特征与模糊决策的海底地形可导航性分析方法

基于多波束测深数据和图像匹配技术的水下地形辅助导航方法需要对实施区域的地形可导航性进行评估,其中的地形独特性计算需要提取图像特征,并利用各特征参数进行综合评判。地形图像的直方图包含实际地理区域的起伏程度信息,通过定义直方图复杂度对此信息进行了有效提取。均方根对比度和拉普拉斯模方和分别侧重描述了地形整体和局部的变化程度,图像的二维熵从信息论的角度反映了地理区域包含的信息量。此外,依据单一特征参数对于待评价地形的可导航性进行排名,其结果存在不一致性,利用模糊综合评判对各参数的信息进行了有效综合。通过实测多波束地形数据仿真分析,基于图像纹理特征的地形匹配方法,在模糊评判结果最优的地形区域能够将匹配误差限制在2 m以内,结果验证了该可导航性分析方法的有效性。     

Implementation Scheme of Two-Photon Post-Quantum Correlations

The pre-and post-selection processes of the "two-state vector formalism" lead to a fair sampling loophole in Bell test, so it can be used to simulate post-quantum correlations. In this paper, we propose a physical implementation of such a correlation with the help of quantum non-demolition measurement, which is realized via the cross-Kerr nonlinear interaction between the signal photon and a probe coherent beam. The indirect measurement on the polarization state of photon is realized by the direct measurement on the phase shift of the probe coherent beam, which enhances the detection efficiency greatly and leaves the signal photon unabsorbed. The maximal violation of the CHSH inequality 4 can be achieved by pre-and post-selecting maximally entangled states. The reason why we can get the post-quantum correlation is that the selection of the results after measurement opens fair-sampling loophole. The fair-sampling loophole opened here is different from the one usually used in the currently existing simulation schemes for post-quantum correlations,which are simulated by selecting the states to be measured or enlarging the Hilbert space. So, our results present an alternative way to mimic post-quantum correlations.     

Quantum superdense coding via cavity-assisted interactions

Quantum superdense coding (QSC) is an example of how entanglement can be used to minimize the number of carriers of classical information. This paper proposes two schemes for implementing QSC by means of cavity assisted interactions with single-photon pulses. The schemes are insensitive to the cavity decay and the thermal field, thus it might be realizable based on the current cavity QED techniques.     

Macroscopic resonant tunneling in an rf-SQUID flux qubit under a single-cycle sinusoidal driving

We experimentally demonstrate the observation of macroscopic resonant tunneling(MRT) phenomenon of the macroscopic distinct flux states in a radio frequency superconducting quantum interference device(rf-SQUID) under a singlecycle sinusoidal driving.The population of the qubit exhibits interference patterns corresponding to resonant tunneling peaks between states in the adjacent potential wells.The dynamics of the qubit depends significantly on the amplitude,frequency,and initial phase of the driving signal.We do the numerical simulations considering the intra-well and interwell relaxation mechanism,which agree well with the experimental results.This approach provides an effective way to manipulate the qubit population by adjusting the parameters of the external driving field.     

线性RFDE和线性NFDE在一致渐近稳定性上的等价性问题

借助于特征方程已研究了标量常微分方程和标量微分差分方程之间的稳定性的等价性问题。本文就n维系统用Liapunov泛函讨论线性RFDE和线性NFDE之间在一致渐近稳定性上的等价性问题,获得某些结果。     

具多滞量和正负系数中立型微分方程解的渐近性质

该文考虑多滞量和正负系数中立型方程[x(t)-sum from n=1 to l(1/n)C_A(t)x(t-r_n)] sum from i=1 to (1/i)P_i(t)x()t-τ_i)-sum from j=1 to n(1/j)Q_j(t)x(t-σ_j)=0,其中C_A(k=1,…,l),P_i(i=1,…,m),Q_j(j=1…,n)∈C([to,∞co),R~ ),0≤τ_l<…<τ_m,0≤σ_1<…<σ_n,0相似文献   

ZnS:ErF3电致发光薄膜2H11/2,4S3/2→4I15/2发光的猝灭过程

本文通过ZnS:ErF3交流电致发光薄膜发光光谱和发光衰减特性研究了Er3+离子2H11/2,3S3/2发光的猝灭过程,实验结果表明由于Er3+离子间多极矩相互作用,一个激发的Er3+离子从2H11/2态无辐射弛豫到4F9/2态,同时另一个激发的Er3+离子从4F7/2或4F5/2+4F3/2态跃迁到2H9/2或4G11/2态的交叉弛豫过程是2H11/2,4S3/2发光浓度猝灭的一个主要机制,交叉弛豫几率随着掺杂浓度的增加而增大,根据在固定掺杂浓度下2H11/2,4S3/2、4F9/2发光衰减时间不随激发密度而改变的实验结果,排除了处于激发的Er3+离子之间直接能量传递的可能性,这结果与扩散限制的能量传递理论相符。     

新疆化学会召开首届会员代表大会

新疆维吾尔自治区化学会于1981年11月20日至24日召开了首届会员代表大会,来自全疆科研、高等院校、生产部门以及解放军驻疆科研部门约30个单位81名各族代表出席了会议。会议交流和讨论了学术论文、专题报告45篇,介绍了代表们近期在稀有元素分析、量子化学理论、计算机在分析仪器上应用和化学教材评价等方面的研究成果和经验体会。大会选举产生了由34人组成的新疆化学会首届理事会,组成了学术、编辑、科普三个工作委员会,以及     

Observational Study of Annual Variations of the Surface Energy Balance Components at Zhongshan Station of Antarctica in 1990

From February 1990 to January 1991, the measurement experiment was carried out at Zhongshan station, East Antarctica. In the experiment, measurements of the surface radiative fluxes and wind, temperature and humidity profiles in the lowest 32 m in the atmosphere boundary layer were made throughout the year. The regime of the surface energy balance was analysed based on the observed data. The conclusion was derived that in warm season (from Nov. to Feb.), large amounts of energy are absorbed by the surface and then transported to the atmosphere in the form of sensible and latent heat, while in cold season (from Mar. to Oct.) continually radiative cooling of the surface occurs.     

1,3,4-均三唑并[2,1-b]-1,3,4-噻二唑衍生物的合成及生物活性

以5-对甲苯基-1-氨基-2-巯基-1,3,4-均三唑和取代苯氧乙酰异硫氰酸酯为原料, 合成了10个未见文献报道的5-对甲苯基-2-取代苯氧乙酰氨基均三唑并[2,1-b]-1,3,4-噻二唑类化合物, 通过元素分析, 1H NMR, IR和MS确定化合物的结构, 初步生物活性测试表明目标化合物具有较好的除草活性.