Web表格的实体列发现算法

针对机器无法理解Web表格语义信息的问题,传统的实体列发现方法通常依靠表头信息和知识库发现实体列,不适用于没有表头的Web表格。为此,提出一种基于列值间近似依赖关系和规范化的Web表格实体列发现算法,对无表头或者无法恢复出完整表头的表格甚至多实体列表格进行实体列标注。由Web表格中的属性值探测出Web表格属性间内在的近似函数依赖关系,根据Web表格的特点对噪声函数依赖进行删减,通过函数依赖集进行规范化,得到Web表格的实体列。与利用知识库进行实体列探测的算法相比,该算法不依赖表头信息,召回率和精确度均提高了3%~5%,适用性更强。

压缩数据上的关系代数操作算法

针对在大数据管理中,在压缩的数据上无需解压即可进行相关操作的问题,在数据服从正态分布的前提下,根据列数据存储的特点,提出了一种新的面向列存储的压缩方法——CCA。首先,通过对列数据的长度进行归类;然后,采用抽样的方法获得重复度较高的前缀;最后,使用字典编码进行压缩,提出了列索引(CI)和列实体(CR)作为数据压缩结构来降低大数据存储的空间需求,从而直接有效地在压缩数据上支持选择、投影、连接等基本操作,并实现了基于CCA的数据库原型系统——D-DBMS。理论分析和在1 TB数据上的实验结果表明,该压缩算法能够显著提高大数据的存储效率和数据操作性能,与BAP和TIDC压缩方法相比,在压缩率分别提高了51%、14%;在执行速度上提高了47%、42%。

The latest advances of experimental research on targeted gene therapy for prostate cancer

The absence of effective therapies for castration-resistant prostate cancer(CRPC) establishes the need to develop novel therapeutic modality, such as targeted gene therapy, which is ideal for the treatment of CRPC. But its application has been limited due to lack of favorable gene vector and the reduction of "bystander effect". Consequently, scientists all over the world focus their main experimental research on the following four aspects: targeted gene, vector, transfer means and comprehensive therapy. In this paper, we reviewed the latest advances of experimental research on targeted gene therapy for prostate cancer.

Molecular phylogeny of Bactrocera species （Diptera： Tephritidae） inferred from mitochondrial 16s rDNA sequences

The fruit flies of the Bactrocera （Diptera： Tephritidae） are one of the major economically important insects in Asia. So far, there are at least seven species found in Chongqing, China. By using mitochondrial 16s rDNA sequences, the phylogenetic relationships among seven Bactrocera species, Bactrocera cucurbitae （Coquillett）, B. tau （Walker）, B. diaphora （Hendel）, B. caudata （Fabricius）, B. scutellata （Hendel）, B. dorsalis （Hendel）, and B. minax （Enderlein） were investigated. Nucleotide diversity within species ranged from 0.3% to 10.9%. According to the result, B. cucurbitae （Coquillett）, B. tau （Walker）, B. diaphora （Hendel）, and B. caudata （Fabricius） have no enough sites to be distinguished among the other species in the 347bp nucleotide sequences of the 16s rDNA gene. At the same time, excluding B. scutellata （Hendel） and B. minax （Enderlein）, the other species recognition sites are not only too little but also discontinuous. Phylogenetic trees calculated from both maximum parsimony and neighbor-joining phylogenetic analysis methods showed that B. cucurbitae and B. tau were closely related, B. diaphora （Hendel） and B. caudata （Fabricius） also had a close relationship. B. minax （Enderlein） has a furthest relationship from the other 6 species. From the results, we can infer that the our data supports previous classification of Bactrocera based on morphological characters in other words, but the Bactrocera subgenera, Zeugodacus is polyphyletic.

Experimental demonstration of λ/8 DFB semiconductor laser array for 1.3 μm CWDM system

In this article,we report the first experimental demonstration of an eight-wavelength λ/8 phased-shifted laser array based on the REC technique in the 1.3 μm wavelength domain.Measurement results exhibit good linearity of lasing wavelength with+/-0.35 nm wavelength residual.The SLM property was ensured with SMSRs all larger than 38 dB.Moreover,the directmodulation performance was also tested.The experimental results show that the modulation bandwidth can reach up to 13GHz even at the small injection current of 40 mA and the measured spurious-free dynamic range(SFDR)is up to 87 dB/Hz2/3,which shows good linearity.These measurements show that REC-based λ/8 phased-shifted laser array has good modulation performance and it may find potential application in actual fiber-optic systems.