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991.
Wu-Chun Chung Hung-Pin Lin Shih-Chang Chen Mon-Fong Jiang Yeh-Ching Chung 《Automated Software Engineering》2014,21(4):489-508
As data exploration has increased rapidly in recent years, the datastore and data processing are getting more and more attention in extracting important information. To find a scalable solution to process the large-scale data is a critical issue in either the relational database system or the emerging NoSQL database. With the inherent scalability and fault tolerance of Hadoop, MapReduce is attractive to process the massive data in parallel. Most of previous researches focus on developing the SQL or SQL-like queries translator with the Hadoop distributed file system. However, it could be difficult to update data frequently in such file system. Therefore, we need a flexible datastore as HBase not only to place the data over a scale-out storage system, but also to manipulate the changeable data in a transparent way. However, the HBase interface is not friendly enough for most users. A GUI composed of SQL client application and database connection to HBase will ease the learning curve. In this paper, we propose the JackHare framework with SQL query compiler, JDBC driver and a systematical method using MapReduce framework for processing the unstructured data in HBase. After importing the JDBC driver to a SQL client GUI, we can exploit the HBase as the underlying datastore to execute the ANSI-SQL queries. Experimental results show that our approaches can perform well with efficiency and scalability. 相似文献
992.
993.
压力流化床燃烧技术近二十年来在世界上得到很大发展。煤的湿法给料系统具有比干法输送系统更简单,运行调节更可靠等优点。煤水混合物可泵送的水分在25%左右,煤的粒度一般为0~6mm,表现为非牛顿的假塑性流体特性,通过级配来达到一定的稳定性和良好输送性能,且流动阻力低,不用添加剂即可实现泵送,它的应用使压力流化床的燃烧制备和输送系统成本大大降低。 相似文献
994.
Incorporating mutation scheme into krill herd algorithm for global numerical optimization 总被引:1,自引:1,他引:0
Gaige Wang Lihong Guo Heqi Wang Hong Duan Luo Liu Jiang Li 《Neural computing & applications》2014,24(3-4):853-871
Recently, Gandomi and Alavi proposed a robust meta-heuristic optimization algorithm, called Krill Herd (KH), for global optimization. To improve the performance of the KH algorithm, harmony search (HS) is applied to mutate between krill during the process of krill updating instead of physical diffusion used in KH. A novel hybrid meta-heuristic optimization approach HS/KH is proposed to solve global numerical optimization problem. HS/KH combines the exploration of harmony search (HS) with the exploitation of KH effectively, and hence, it can generate the promising candidate solutions. The detailed implementation procedure for this improved meta-heuristic method is also described. Fourteen standard benchmark functions are applied to verify the effects of these improvements, and it is demonstrated that, in most cases, the performance of this hybrid meta-heuristic method (HS/KH) is superior to, or at least highly competitive with, the standard KH and other population-based optimization methods, such as ACO, BBO, DE, ES, GA, HS, KH, PSO, and SGA. The effect of the HS/FA parameters is also analyzed. 相似文献
995.
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. 相似文献
996.
In this paper, a new Chinese character recognition (CCR) approach is proposed based on the fuzzy clustering analysis theory. Chinese characters (CCs) have various similar radicals and stroke components, which make it difficult to recognize features in the CCR process. At the same time, the recognition accuracy and the efficiency are lower when the objects to be recognized are complex. In order to solve these problems, a fuzzy clustering analysis method is introduced to enhance the computing efficiency. At first, the CCs including learning samples and testing samples are transformed into binarization templates in the form of matrixes. Then, the minimum distance algorithm is applied to calculate ‘distances’ between the testing sample templates and the learning sample templates. At last, the character recognition can be achieved by searching the minimum distance from the results. The experiment results of the CCR process can prove the effectiveness and accuracy of the new method. 相似文献
997.
With the fast explosive rate of the amount of image data on the Internet, how to efficiently utilize them in the cross-media scenario becomes an urgent problem. Images are usually accompanied with contextual textual information. These two heterogeneous modalities are mutually reinforcing to make the Internet content more informative. In most cases, visual information can be regarded as an enhanced content of the textual document. To make image-to-image similarity being more consistent with document-to-document similarity, this paper proposes a method to learn image similarities according to the relations of the accompanied textual documents. More specifically, instead of using the static quantitative relations, rank-based learning procedure by employing structural SVM is adopted in this paper, and the ranking structure is established by comparing the relative relations of textual information. The learning results are in more accordance with the human’s recognition. The proposed method in this paper can be used not only for the image-to-image retrieval, but also for cross-modality multimedia, where a query expansion framework is proposed to get more satisfactory results. Extensive experimental evaluations on large scale Internet dataset validate the performance of the proposed methods. 相似文献
998.
999.
为了大幅降低错流多效蒸发过程的能耗,首次将蒸汽喷射式热泵技术、冷凝水闪蒸和溶液闪蒸等3种节能措施同时运用到错流多效蒸发系统中,并建立了用矩阵方程描述的该系统的数学模型。模型具有很强的通用性,可实现热泵在任意效抽汽的功能,可简化为只有其中若干种节能措施组合或无上述节能措施的错流、并流、逆流多效蒸发系统的模型。在满足约束条件的前提下,模型存在最佳的热泵喷射系数和抽汽位置,同时采用上述3种节能措施且在最佳条件下模型是高效节能的。浓缩氢氧化钠溶液的热泵错流五效蒸发系统的模拟结果表明,当热泵的喷射系数为0.15、抽汽位置在第2效,采用冷凝水闪蒸和溶液闪蒸时系统节省的生蒸汽消耗量高达32.51%。 相似文献
1000.
Jingxian Zhang Dongliang Jiang Qingling Lin 《Journal of the American Ceramic Society》2005,88(4):1054-1056
In this paper, poly(vinyl pyrrolidone) (PVP) was selected as a dispersant for preparation of high concentrated silicon carbide (SiC) slurries in an ethanol (EtOH)/methyl ethylene ketone (MEK) solvent system. The interactions between (1) solvent and powders, (2) the solvent and dispersant, and (3) dispersant and powder were characterized in terms of adsorption and viscosity measurement. It was evidenced that the dispersion of SiC slurries was highly dependent on the solvent composition. Well-stabilized SiC slurries could be obtained using PVP as a dispersant in EtOH/MEK media with the content of EtOH in the 40–50 wt% range. The optimal dosage of PVP as a dispersant was at a PVP/SiC mass ratio of 17 mg/g. Results showed that PVP was an effective dispersant for SiC in EtOH/MEK media. 相似文献