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61.
低温高密核物质测量谱仪(CEE)是研究高重子数密度区核物质性质的重离子碰撞实验谱仪。使用了先进的 SAMPA 电子学读出芯片的时间投影室(TPC)是 CEE 最核心的探测器。在集团重建的过程中,同一排读出板的信号被首先重建成 2 维集团,然后根据 2 维集团的 ADC 加权平均位置重建击中点。当信号 ADC 随漂移时间变化呈峰-谷-峰结构时,一个集团可能被重建成两个或更多击中点,从而提高双径迹分辨能力。使用模拟信号的测试显示,该重建算法在$x/ y$方向可以达到0.100/0.043 cm的位置分辨能力和1.1/2.8 cm的双径迹分辨能力。  相似文献   
62.
初步研究了男性个体辐射敏感性的鉴定方法及标准.采集50名男性志愿者的外周血,分别给予不同剂量X射线照射,采用细胞松弛素B阻断双核法测定微核率(MNF),通过二阶多项拟合法,绘制微核剂量效应选项中心标准曲线,将个人微核剂量效应曲线与标准曲线比对后判断个体辐射敏感性.0.0~2.5 Gy剂量范围内,剂量效应二阶多项拟合的中...  相似文献   
63.
The analysis of the LHCb data on \begin{document}$X(6900)$\end{document} found in the di-\begin{document}$J/\psi$\end{document} system was performed using a momentum-dependent Flatté-like parameterization. The use of the pole counting rule and spectral density function sum rule provides consistent evidence that both confining and molecular states are possible. Alternatively, the nature of \begin{document}$X(6900)$\end{document} cannot be distinguished if only the di-\begin{document}$J/\psi$\end{document} experimental data with current statistics are available. Nevertheless, we found that the lowest state in the di-\begin{document}$J/\psi$\end{document} system likely has the same quantum numbers as \begin{document}$X(6900)$\end{document}, and \begin{document}$X(6900)$\end{document} is probably not interpreted as a \begin{document}$J/\psi-\psi(2S)$\end{document} molecular state.  相似文献   
64.
Optical coherence tomography (OCT) images coupled with many learning techniques have been developed to diagnose retinal disorders. This work aims to develop a novel framework for extracting deep features from 18 pre-trained convolutional neural networks (CNN) and to attain high performance using OCT images. In this work, we have developed a new framework for automated detection of retinal disorders using transfer learning. This model consists of three phases: deep fused and multilevel feature extraction, using 18 pre-trained networks and tent maximal pooling, feature selection with ReliefF, and classification using the optimized classifier. The novelty of this proposed framework is the feature generation using widely used CNNs and to select the most suitable features for classification. The extracted features using our proposed intelligent feature extractor are fed to iterative ReliefF (IRF) to automatically select the best feature vector. The quadratic support vector machine (QSVM) is utilized as a classifier in this work. We have developed our model using two public OCT image datasets, and they are named database 1 (DB1) and database 2 (DB2). The proposed framework can attain 97.40% and 100% classification accuracies using the two OCT datasets, DB1 and DB2, respectively. These results illustrate the success of our model.  相似文献   
65.
陈丹  周斌  郝楠  陈立民 《物理学报》2006,55(10):5555-5561
通过实验证明是否考虑O4的存在对利用天顶散射光测量大气组分含量的结果存在影响.介绍了天顶散射光的观测原理、实验仪器、测量方法、光谱处理以及浓度反演过程.用具体的实验数据说明考虑O4在实验波段内的吸收能提高NO2和O3浓度反演结果的准确性.同时将观测得到的臭氧垂直柱密度与美国TOMS观测数据进行了对比. 关键词: 4')" href="#">O4 臭氧 天顶散射光 DOAS  相似文献   
66.
Community detection has become an important methodology to understand the organization and function of various real-world networks. The label propagation algorithm (LPA) is an almost linear time algorithm proved to be effective in finding a good community structure. However, LPA has a limitation caused by its one-hop horizon. Specifically, each node in LPA adopts the label shared by most of its one-hop neighbors; much network topology information is lost in this process, which we believe is one of the main reasons for its instability and poor performance. Therefore in this paper we introduce a measure named weighted coherent neighborhood propinquity (weighted-CNP) to represent the probability that a pair of vertices are involved in the same community. In label update, a node adopts the label that has the maximum weighted-CNP instead of the one that is shared by most of its neighbors. We propose a dynamic and adaptive weighted-CNP called entropic-CNP by using the principal of entropy to modulate the weights. Furthermore, we propose a framework to integrate the weighted-CNP in other algorithms in detecting community structure. We test our algorithm on both computer-generated networks and real-world networks. The experimental results show that our algorithm is more robust and effective than LPA in large-scale networks.  相似文献   
67.
Semipolar (11\bar 2 \bar 2) ZnO was successfully grown on (112) LaAlO3/(LaAlO3)0.29(Sr2AlTaO6)0.35 substrate by pulsed laser deposition. The epitaxial relationship is [11\bar 23]_{\rm ZnO} // [11\bar 1]_{\rm LAO/LSAT} with the polar axis of [000\bar 1]_{\rm ZnO} pointing to the surface. For ZnO films with thickness of 1.6 μm, the threading dislocation density is ~1 × 109 cm–2, and the density of basal stacking faults is below 1 × 104 cm–1. The (11\bar 2 \bar 2) ZnO exhibits strong D0X emissions with a FWHM of 9 meV and very few green–yellow emissions in the low‐temperature (10 K) and room‐temperature photoluminescence spectra, respectively.

  相似文献   

68.
As more efficient and reliable torches for thermal plasma generation have become available in recent years, the use of thermal plasma as an energy source for pyrolysis/gasification has attracted much interest, and special attention has been paid to waste treatment for resource and energy recovery. Plasma pyrolysis/gasification systems have unique features such as the extremely high reaction temperature and ultra-fast reaction velocity compared to traditional pyrolysis/gasification systems. Plasma pyrolysis/gasification is therefore acknowledged as a novel pyrolysis/gasification technology with great potential in solid waste disposal. This paper gives a comprehensive review on the development of fundamental researches on plasma pyrolysis/gasification systems including direct current (DC) arc plasma system and radio frequency (RF) plasma system with an emphasis on reactor design such as plasma fixed/moving bed reactor system, plasma entrained-flow bed reactor system and plasma spout-fluid bed reactor system.  相似文献   
69.
置换群关于变换后基的强生成集的算法   总被引:1,自引:0,他引:1  
姜豪 《应用数学》1994,7(3):300-305
本文给出置换群关于变换后的基的强生成集的一种算法及其理论证明,并讨论了既约强生成集和最小强生成集的问题。  相似文献   
70.
一种求解多峰函数优化问题的演化算法   总被引:2,自引:0,他引:2  
针对演化计算产生新解无序的问题,提出了基于相似性的邻域搜索策略.利用邻域搜索,可以方便地建立自适应的新解产生机制.针对演化算法设计中存在的搜索效果和效率平衡问题,提出了利用适应值对个体进行分级的搜索策略.通过对个体的分级,可以区分个体在搜索过程中的职能:优秀的个体进行局部极小值的开采;其他的个体进行搜索空间的探索,以发现新的局部极小值.数值实验表明,新算法能有效处理低维多峰函数,能找到所有的全局最优解.对高维多峰函数.也能找到全局最优解.  相似文献   
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