Study of collective user behaviour in Twitter: a fuzzy approach

The study of collective user behaviours in social networking sites has become an increasing important topic in social media mining. Understanding such behaviours has its potential to extract actionable patterns that can be beneficial to develop effective marketing strategies, optimise user experiences and maximise website revenues. With the rapid development of micro-blogging, Twitter has become a richer source of intelligence that can be used to study collective user behaviour, due to its efficient and meaningful user-to-user interactions. However, the classical statistical methods have some drawbacks in bridging the gap between user-generated data and human analysts who mostly use linguistic terms to analyse data and model/summarise knowledge learned. To address this gap, this work proposes a new approach, which employs the mass assignment theory-based fuzzy association rules algorithm (MASS-FARM), for the first time, to extract useful interaction behaviour of Twitter users. The influential factors (including activity time, number of friends/followers and the number of tweets) are represented as fuzzy granules, and the associations amongst are studied by employing MASS-FARM. The collective user behaviours are analysed in the Reply category and the Non-Reply category, respectively. The applicability and usefulness of the proposed method are demonstrated via an empirical study on a collected Twitter data set. The derived results are also discussed and compared with existing works.     

基于条件随机场的低图像质量车牌字符分割

提出一种基于条件随机场的车牌字符分割算法,能够对光照不均、相机拍摄角度造成的低图像质量的车牌图像,特别是日益增多的车牌边框与字符相连接车牌图像进行有效的字符分割。算法首先进行车牌图像校正,然后利用标注车牌数据进行模型学习,对车牌图像像素列进行分类识别,最后组合成车牌字符分割结果。理论分析与实验结果验证了算法的有效性。     

TiB2的SHS合成过程理论分析

在ＴｉＢ２陶瓷材料的自蔓延高温合成（简称ＳＨＳ）过程中，通过改变原料的起始温度，稀释剂的含量和原始颗粒的尺寸等都可以调节合成过程的绝热温度，产物中熔融相的含量，以及燃烧波蔓延的速度，人而最终影响合成产物的结构和性质。本文对上述各种关系进行了理论计算和分析，其结果对实际合成与制备过程将有着重要的指导作用。     

The fatty acids of wax esters and sterol esters from vernix caseosa and from human skin surface lipid

Separation of sterol esters from wax esters in the lipids of vernix caseosa and adult human skin surface was accomplished by column chromatography on MgO. The fatty acids of the sterol esters and wax esters of both samples were separated into saturates and monoenes, and examined in detail by gas liquid chromatography (GLC). The saturated fatty acids of the wax esters of vernix caseosa and of adult human skin surface were remarkably similar. They ranged in chain length from at least C₁₁ to C₃₀, six skeletal types being present: straight even, straight odd, iso, anteiso, other monomethyl branched and dimethyl branched. A large number of patterns of monoenes were observed, each pattern consisting of desaturation of a specific chain at Δ6 or Δ9 plus its extension or degradation products. The mole per cent of the total Δ6 and Δ9 patterns of wax ester fatty acid monoenes of vernix caseosa were 87% and 12%, respectively, and 98% and 1%, respectively, for adult human skin surface lipid. The sterol ester fatty acids of vernix caseosa were much different from those of adult human skin surface: vernix caseosa saturates were largely branched and of lengths greater than C₁₈, whereas the saturates of adult human surface lipid resembled the wax ester fatty acids. Of the vernix caseosa monoene patterns, the mole per cent was 30% Δ6 and 70% Δ9, whereas of the adult human skin surface sterol ester fatty acids 89% were Δ6 and 11% Δ9. Chain extension was particularly pronounced in the sterol ester fatty acid monoenes of vernix caseosa amounting to 7–8 C₂ units in some cases. The fatty acids of the sterol esters of both vernix caseosa and adult human skin surface appear to be derived from the sebaceous gland and from the keratinizing epidermis, but those of the wax esters are from the sebaceous glands only.     

聚丙烯结构壁管专用料的开发

阐述了塑料结构壁管的基本情况和国内外现状．重点就扬子石油化工股份有限公司研究院研制的聚丙烯结构壁管专用料的情况进行了介绍。     

氧化铝上吸附平衡与动力学的分形特性

在实验测定氧化铝吸附氮气的平衡和动力学过程的基础上 ,由平衡数据得到分形维数 ,对动力学结果分别用欧氏几何和分形几何的动力学模型进行处理 ,比较两种方法得到的扩散系数之间的差别。结果表明 :粉状氧化铝的分形维数为 2 .12 ;采用分形动力学模型得到的扩散系数同欧氏几何扩散模型的结果不一样 ,扩散系数不随浓度的变化而改变 ;而欧氏几何扩散模型中的扩散系数随浓度变化发生改变 ,且变化符合Darken关系     

Holographic algorithms on bases of rank 2

An essential problem in the design of holographic algorithms is to decide whether the required signatures can be realized under a suitable basis transformation (SRP). For holographic algorithms with matchgates on domain size 2, , ,  and  have built a systematical theory. In this paper, we reduce SRP on domain size k≥3$k\ge 3$ to SRP on domain size 2 for holographic algorithms with matchgates on bases of rank 2. Furthermore, we generalize the collapse theorem of [3] to domain size k≥3$k\ge 3$.     

Efficient object detection based on selective attention

In this paper, we make use of biologically inspired selective attention to improve the efficiency and performance of object detection under clutter. At first, we propose a novel bottom-up attention model. We argue that heuristic feature selection based on bottom-up attention can stably select out invariant and discriminative features. With these selected features, performance of object detection can be improved apparently and stably. Then we propose a novel concept of saccade map based on bottom-up attention to simulate the saccade (eye movements) in vision. Sliding within saccade map to detect object can significantly reduce computational complexity and apparently improve performance because of the effective filtering for distracting information. With these ideas, we present a general framework for object detection through integrating bottom-up attention. Through evaluating on UIUC cars and Weizmann–Shotton horses we show state-of-the-art performance of our object detection model.     

Selective O-methylation of phenol with dimethyl carbonate over X-zeolites

The O-methylation of phenol with dimethyl carbonate proceeds selectively in the vapor phase over alkali ion exchanged X-zeolites. Thus, a 76% yield of anisole was obtained with a 93% selectivity over NaX at 553 K. The participation of basic sites in the O-methylation is suggested.     

Effect of morphology on brittle-ductile transition of HPDE/CaCO3 blends

In this paper, the results of a series of investigations of the effect of morphology on the brittle-ductile transition for HDPE/CaCO₃ blends are summarized: (1) It seems the critical ligament thickness increases with increasing matrix toughness; (2) the interphase adhesion is very important for the toughness of HDPE/CaCO₃ blends; (3) small particles are more effective than large ones; (4) CaCO₃ particle aggregation will reduce toughening efficiency; (5) uniform CaCO₃ particle size is more effective than heterogeneous size for the toughening of HDPE. It is expected that a polymer with higher modulus as well as higher toughness will be obtained by appropriately controlling the morphology of HDPE/CaCO₃ blends. © 1993 John Wiley & Sons, Inc.