Research on the Characteristics of the Fiber Laser Based on Distributed Feedback Bragg Grating and the Demodulation Method of Its Wavelength Shift in Sensor Application

相移分布反馈光纤激光器（Phase-shiftDistributedFeedbackFiberlaser）是光纤激光器发展的一个重要方向，由于其具有线宽窄、噪声小等优点，可作为光纤传感、光纤遥感、高精度光谱以及光纤通信领域的高质量的光源。如果能将光纤激光应用于光纤传感领域中，必将大大提高光纤传感器的性能。为此结合传感器的特点进行光纤激光器的研究有着重要的理论和实际意义。 本文主要的研究工作体现在两个方面： 一、DFB光纤激光器的输出谱线特性研究。首先，使用FOGS_BG仿真工具理论上定量的得到了相移量与四分之一波长相移光纤光栅透射峰谱线展宽大小的对应关系；相移量的改变与透射峰波长漂移的关系...As one of important development in the field of fiber lasers, single frequency, continuous wave lasers are required for a wide range of applications in optical communications and optical fiber sensor. Here, distributed feedback (DFB) fiber lasers are attractive due to their reliability, fiber compatibility and narrow linewidth and they present a promising alternative to semiconductor DBR and DFB l...学位：理学硕士院系专业：信息科学与技术学院电子工程系_无线电物理学号：20043001

对我国现阶段“基金热”的思考

我国证券投资基金发展迅速,对资本市场的规模壮大与结构调整深具意义,但近期渐露过热迹象。研究从现阶段“基金热”的成因和“基金热”背后存在的问题进行探讨,并通过保持基金发展的节奏协调、完善基金发展的制度环境等方面提出政策建议

"基金热"的泡沫是不是破了

基金从年初的狂热到近期的急冷,经历了一个超常规的大起大落的发展。研究对"基金热"冷却的原因 进行分析,阐述了基金发展过程中所出现的一些问题,并对基金未来的发展提出一些建议

SPT—Method of Fast Calculation FreeCube

文章首先分析了目前国内外数据立方体计算的研究现状,指出其优缺点。接着在free-set的概念上,给出了一系列相关定义,挖掘了free-set的性质,建立了FreeCube的概念结构。就FreeCube的计算而言,充分考虑到free-set的性质,结合BUC算法的特点,提出了高效的算法SPT(Selecting-PartitionandTrimmingComputationofFreeCube),并从多个角度进行了实验,与相关工作做了对比,说明该算法的优越性。First of all,the current domestic and international research situation of Data Cube calculation is analyzed.Then the thesis points out its merits and demerits.And it gives out a series of related definitions on the free-set conception,excavates the free-set property and establishes the concept construction of FreeCube.With regard to FreeCube calculation,fully considering the free-set characteristics while combining the characteristics of BUC’s calculation,the thesis puts forward an efficient calculation way SPT(Selecting-Partition and Trimming Computation of FreeCube),and while comparing with related work,it engages in experiments from many aspects,which illustrates the superiority of the algorithm.FreeCube maintenance problem is also discussed theoretically.福建省自然基金资助项目(编号:A0310008);; 福建省高新技术研究开放计划重点资助项目(编号:2003H043

LSNCCP:A Clustering Algorithm Based on the Largest Set of Not-Covered Core Points

聚类在数据挖掘、模式识别等许多领域有着重要的应用 提出了一种新颖的聚类算法 :一种基于最大不相含核心点集的聚类算法LSNCCP(aclusteringalgorithmbasedonthelargestsetofnot coveredcorepoints) 在密度定义的基础上 ,考察核心点之间的距离关系 ,定义相含、相交、相离这 3种核心点之间的关系 ,最后找出一个最大不相含核心点集 ,在此基础上进行聚类 ,并且找到解决丢失点问题的快速方法 该最大不相含核心点集只是全部核心点集合的一个很小的子集 ,因此有效地缩减了同类算法中搜寻核心点的时间 理论和实验上证明了这种算法的可行性和优越性Clustering is an important application area for many fields including data mining, pattern recognition, etc. In this paper, a novel clustering algorithm LSNCCP(a clustering algorithm based on the largest set of not-covered core points) is proposed. On the basis of the definition of density, the distance between the core points is discussed. And then, the three essential distance relation: covered core points, intersectant core points, and separate core points. Finally, the largest set of not-covered core points is found and based on the set the data can cluster very well. Because the largest set of not-covered core points is a lesser subset of the all core points, the new algorithm cuts short the time of searching all core points in the similar algorithms. The feasibility and the advantage or the new algorithm are proved in theory and experiment.福建省自然科学基金项目 (A0 3 10 0 0 8) ;; 福建省高新技术研究开放计划重点项目 (2 0 0 3H0 43

Characterizing Nitrogen Saturation of the Wuchuan Headwater Stream in the Southeast of China

以九龙江流域典型的农业源头溪流——五川溪为研究区域,开展每月一次共2年的nO3-采样用于溪流氮饱和特征的研究.结果表明,2005年和2007年溪流的nO3-浓度分别为35.5~319.5μEQl-1和5.0~353.6μEQl-1,根据STOddArd和TrAAEn提出的氮饱和划分准则,五川流域分别处于氮饱和阶段2/3和阶段2,接近氮饱和.氮饱和阶段随着nO3-浓度的增加而上升,五川溪流的氮饱和阶段存在着时间上的变化.河流生态系统中氮负荷增加,使河流达到氮饱和状态,并最终改变溪流系统硝化和反硝化等氮的生物地球化学循环过程.随着nO3-浓度的增加,五川源头溪流已成为流域内重要的nO3-源.NO3-concentrations sampled monthly in the Wuchuan stream,which is a small agricultural headwater stream in the southeast of China,within two years,were used to study the stream′s nitrogen saturation characteristics.Results showed that NO3-concentrations varied from 35.5 to 319.5 μeqL-1 in 2005 and from 5.0 to 353.6 μeqL-1 in 2007.And,according to the criteria proposed by Stoddard and Traaen,the nitrogen saturation status of the stream was at stage 2 or 3,and stage 2,respectively.Both stages were closed to saturation.It was found that the saturation stage would increase with the NO3-concentration,which caused the change of nitrogen saturation stage in the Wuchuan stream over time.The increasing of nitrogen loadings has led to the stream nitrogen saturation and eventually can alter nitrification,denitrification and other nitrogen biogeochemical cycles in the stream ecosystem.国家自然科学基金资助项目(41175130);教育部新世纪优秀人才支持计

基于带权词格的循环神经网络句子语义表示建模

目前,循环神经网络(recurrent neural network, RNN)已经被广泛应用于自然语言处理的文本序列语义表示建模.对于没有词语分隔符的语言,例如中文,该网络以经过分词预处理的词序列作为标准输入.然而,非最优的分词粒度和分词错误会对句子语义表示建模产生负面作用,影响后续自然语言处理任务的进行.针对这些问题,提出基于带权词格的循环神经网络模型.该模型以带权词格作为输入,在每个时刻融合多个输入向量和对应的隐状态,融合生成新的隐状态.带权词格是一种包含指数级别分词结果的压缩数据结构,词格中的边权重在一定程度上体现了不同分词结果的一致性.特别地,利用词格权重作为融合函数中权重建模的监督信息,进一步提升了模型句子语义表示的学习效果.相比于传统循环神经网络,该模型不仅能够缓解分词错误对句子语义建模产生的负面影响,同时使得语义建模具有更强的灵活性.在情感分类和问句分类2个任务上的实验结果证明了该模型的有效性.国家自然科学基金项目(61672440);;北京语言大学语言资源高精尖创新中心资助;;国家语言文字工作委员会一般项目(YB135-49);;中央高校基本科研业务费专项资金项目(ZK1024);;苏州大学江苏省计算机信息处理技术重点实验室开放课题(KJS1520)~

各种过渡金属、合金和半导体电极上的表面拉曼光谱

各种过渡金属、合金和半导体电极上的表面拉曼光谱高劲松任斌黄群健王仲权蔡文斌李筱琴刘峰名佘春兴田中群（厦门大学固体表面物理化学国家重点实验室化学系物理化学研究所361005）SurfACErAMAnSPECTrOSCOPyOfTrAnSITIOnME...国家自然科学基金委;国家教委资

Study of Nano-modification PMMA Optical Waveguide Thin-films

主要研究纳米颗粒改性甲基丙烯酸甲酯预聚物(PMMA)的工艺,以及光波导薄膜的制备技术和性能。具体采用机械混合方式进行纳米颗粒掺杂和旋涂技术,旨在提高PMMA光波导层的热稳定性和折射率,并优化实验工艺条件使光波导薄膜达到透明、均匀、致密及无气孔的要求,从而降低其光传输损耗。实验在玻璃和硅基片上制备了纳米改性的PMMA光波导薄膜,并利用各种先进的测试手段对其进行了性能测量和表征分析,结果表明:纳米SiO2颗粒能够大幅度地提高PMMA光波导层的热稳定性和玻璃化转变温度Tg,而纳米TiO2颗粒使其折射率也有显著的提高。In this paper, the modification process of PMMA with nano-particles and the preparation of PMMA optical waveguide thin-films were studied. By taking the film spinning technology and the mechanic-mixing modification process with nano-particals, this work aimed at improving the thermal stability and the refractive index of PMMA and making its optical waveguide thin-films with well-distributed compact and less-blister. The configuration and properties of PMMA thin -films were observed and analyzed by different advanced technologies. The results show that nano-silicon dioxide can improve its thermal stability as well as Tg greatly, and nano titanium dioxide can increase the refractive index of PMMA.福建省青年科技人才创新项目资金资助(2001J024

Factor Price Distortion and Direction of Technological Progress：Evidence from China＇s Industry Sectors

技术进步的偏向性是影响收入分配份额的重要原因,但鲜有文献研究技术进步方向的影响因素。利用1993—2012年中国工业行业的面板数据,使用标准化供给面系统方法估算了各工业行业的技术进步偏向指数,在此基础上实证研究了要素价格扭曲对技术进步方向的影响。研究结果表明,中国工业行业的技术进步呈现出显著的资本偏向性,而要素市场的价格扭曲对技术进步方向有显著作用;其中,劳动力价格扭曲会致使技术进步偏向于资本,同样,资本价格扭曲则会致使技术进步偏向于劳动力。There is a dearth of literature exploring the factors which impact upon the direction of technological progress,although directed technical progress is an important influencing factor on the distribution of income share. Based on the panel data of China＇s industry sectors from 1993 to 2012,this paper uses the＂normalized supply-side system＂to estimate the bias index of technological progress of China＇s industry sectors. Based on these indexes,this paper empirically studies the effect of factor price distortion on the direction of technological progress. The results reveal that the technological progress in most China＇s industry biases to capital. Moreover,the study finds that the price distortion in China＇s factor market has significant effect on the direction of technological progress,where labor price distortion will bring the technological progress bias to capital while capital price distortion will bring the technological progress bias to labor. This study provides a new angle for studying the relationship between factor price distortion and factor income distribution.国家自然科学基金青年项目“人口老龄化下的技术进步方向与要素收入份额”（71503220）; 厦门大学校长基金“要素市场扭曲、偏向性技术进步与要素收入份额”（20720171028）; 福建省哲学社会科学规划项目“基于事后估计空间权重的空间计量模型研究”（FJ2016B175）; 中央高校基本科研业务经费项目“创新网络中的知识获取——中国手机产业的研究”（20720151029）; 福州市科技局项目“闽台农产品可追溯电子凭证互认系统研发及应用示范”（2015-G-60