Ambient Assisted Living(AAL) is becoming an important research field. Many technologies have emerged related with pervasive computing vision, which can give support for AAL. One of the most reliable approaches is base...Ambient Assisted Living(AAL) is becoming an important research field. Many technologies have emerged related with pervasive computing vision, which can give support for AAL. One of the most reliable approaches is based on wireless sensor networks(WSNs). In this paper, we propose a coverage-aware unequal clustering protocol with load separation(CUCPLS) for data gathering of AAL applications based on WSNs. Firstly, the coverage overlap factor for nodes is introduced that accounts for the degree of target nodes covered. In addition, to balance the intra-cluster and inter-cluster energy consumptions, different competition radiuses of CHs are computed theoretically in different rings, and smaller clusters are formed near the sink. Moreover, two CHs are selected in each cluster for load separation to alleviate the substantial energy consumption difference between a single CH and its member nodes. Furthermore, a backoff waiting time is adopted during the selection of the two CHs to reduce the number of control messages employed. Simulation results demonstrate that the CUCPLS not only can achieve better coverage performance, but also balance the energy consumption of a network and prolong network lifetime.展开更多
社交网络的影响力最大化是网络分析领域的关键问题,在广告宣传、舆情控制等场景有着诸多应用。该问题指在一个社交图中选取一组源节点,使得所选取的节点集合能够在某种传播模型中形成最大的影响力。由于节点选取问题是典型的NP-hard问题...社交网络的影响力最大化是网络分析领域的关键问题,在广告宣传、舆情控制等场景有着诸多应用。该问题指在一个社交图中选取一组源节点,使得所选取的节点集合能够在某种传播模型中形成最大的影响力。由于节点选取问题是典型的NP-hard问题,在大型网络中会遭遇组合爆炸。近些年来,国内外学者一般采用启发式算法求得问题的近似解。然而,现有工作鲜有考虑到节点选取的成本,所得到的解无法满足实际应用中的预算条件。针对此问题,首先考虑节点选取的成本约束,并对成本受限条件下的社交网络影响最大化问题进行数学建模;其次为节约源节点的冗余覆盖成本,使用快速贪婪模块度最大化算法对网络进行社区聚类;然后根据社区聚类结果在蚂蚁游走过程中引入跨社区游走因子,以增强蚂蚁在网络上的全局游走能力;最后,在蚁群系统中设计了新的启发式信息和信息素形式,并将评估函数设计为罚函数的形式以控制节点的选取成本,提出了基于社区发现的蚁群系统算法(Community Detection-based Ant Colony System,CDACS)。在真实数据集上的实验结果表明,CDACS算法比未加入跨社区因子的蚁群算法取得的覆盖率平均提高了15%左右,运行时间平均减少了约20%。在覆盖效果上相比其他现有的影响力最大化算法都取得了显著的改进。此外,CDACS在不同数据集上所产生的解均满足不同的成本限制,体现了CDACS算法在成本控制上的可靠性。展开更多
With the gradually development of economy in China, people＇s living stan- dards have been improved, which makes people have higher and higher require- ments on the quality of life, and thus community service has beco...With the gradually development of economy in China, people＇s living stan- dards have been improved, which makes people have higher and higher require- ments on the quality of life, and thus community service has become and essential part in people＇s life. In order to understand the basic building blocks of community service organizations in different cities in China, classification comparison was made to the data of 31 cities in China from China Statistical Year Book （2014） by using SPSS clustering method and the fuzzy clustering method, so as to find out the dif- ferences and the causes of the differences, with the aim to promote the manage- ment of relevant government and personnel.展开更多
The construction of virtual community in foreign language learning is a comprehensive foreign language learning environment integrated with foreign language vocabulary database construction and vocabulary retrieval, c...The construction of virtual community in foreign language learning is a comprehensive foreign language learning environment integrated with foreign language vocabulary database construction and vocabulary retrieval, combining the virtual reality technology to construct the language environment of foreign language learning. The virtual community of foreign language leaming can improve the sense of language authenticity in foreign language learning and improve the quality of foreign language teaching. A method of building a virtual community for foreign language learning is proposed based on data mining technology, data acquisition and feature preprocessing model for building semantic vocabulary of foreign language learning is constructed, the linguistic environment characteristics of the semantic vocabulary data of foreign language learning is analyzed, and the semantic noumenon structure model is obtained. Fuzzy clustering method is used for vocabulary clustering and comprehensive retrieval in the virtual community of foreign language learning, the performance of vocabulary classification in foreign language learning is improved, the adaptive semantic information fusion method is used to realize the vocabulary data mining in the virtual community of foreign language learning, information retrieval and access scheduling for virtual communities in foreign language learning are realized based on data mining results. The simulation results show that the accuracy of foreign language vocabulary retrieval is good, improve the efficiency of foreign language learning.展开更多
基金supported by the National Nature Science Foundation of China (61170169, 61170168)
文摘Ambient Assisted Living(AAL) is becoming an important research field. Many technologies have emerged related with pervasive computing vision, which can give support for AAL. One of the most reliable approaches is based on wireless sensor networks(WSNs). In this paper, we propose a coverage-aware unequal clustering protocol with load separation(CUCPLS) for data gathering of AAL applications based on WSNs. Firstly, the coverage overlap factor for nodes is introduced that accounts for the degree of target nodes covered. In addition, to balance the intra-cluster and inter-cluster energy consumptions, different competition radiuses of CHs are computed theoretically in different rings, and smaller clusters are formed near the sink. Moreover, two CHs are selected in each cluster for load separation to alleviate the substantial energy consumption difference between a single CH and its member nodes. Furthermore, a backoff waiting time is adopted during the selection of the two CHs to reduce the number of control messages employed. Simulation results demonstrate that the CUCPLS not only can achieve better coverage performance, but also balance the energy consumption of a network and prolong network lifetime.
文摘社交网络的影响力最大化是网络分析领域的关键问题,在广告宣传、舆情控制等场景有着诸多应用。该问题指在一个社交图中选取一组源节点,使得所选取的节点集合能够在某种传播模型中形成最大的影响力。由于节点选取问题是典型的NP-hard问题,在大型网络中会遭遇组合爆炸。近些年来,国内外学者一般采用启发式算法求得问题的近似解。然而,现有工作鲜有考虑到节点选取的成本,所得到的解无法满足实际应用中的预算条件。针对此问题,首先考虑节点选取的成本约束,并对成本受限条件下的社交网络影响最大化问题进行数学建模;其次为节约源节点的冗余覆盖成本,使用快速贪婪模块度最大化算法对网络进行社区聚类;然后根据社区聚类结果在蚂蚁游走过程中引入跨社区游走因子,以增强蚂蚁在网络上的全局游走能力;最后,在蚁群系统中设计了新的启发式信息和信息素形式,并将评估函数设计为罚函数的形式以控制节点的选取成本,提出了基于社区发现的蚁群系统算法(Community Detection-based Ant Colony System,CDACS)。在真实数据集上的实验结果表明,CDACS算法比未加入跨社区因子的蚁群算法取得的覆盖率平均提高了15%左右,运行时间平均减少了约20%。在覆盖效果上相比其他现有的影响力最大化算法都取得了显著的改进。此外,CDACS在不同数据集上所产生的解均满足不同的成本限制,体现了CDACS算法在成本控制上的可靠性。
文摘With the gradually development of economy in China, people＇s living stan- dards have been improved, which makes people have higher and higher require- ments on the quality of life, and thus community service has become and essential part in people＇s life. In order to understand the basic building blocks of community service organizations in different cities in China, classification comparison was made to the data of 31 cities in China from China Statistical Year Book （2014） by using SPSS clustering method and the fuzzy clustering method, so as to find out the dif- ferences and the causes of the differences, with the aim to promote the manage- ment of relevant government and personnel.
文摘The construction of virtual community in foreign language learning is a comprehensive foreign language learning environment integrated with foreign language vocabulary database construction and vocabulary retrieval, combining the virtual reality technology to construct the language environment of foreign language learning. The virtual community of foreign language leaming can improve the sense of language authenticity in foreign language learning and improve the quality of foreign language teaching. A method of building a virtual community for foreign language learning is proposed based on data mining technology, data acquisition and feature preprocessing model for building semantic vocabulary of foreign language learning is constructed, the linguistic environment characteristics of the semantic vocabulary data of foreign language learning is analyzed, and the semantic noumenon structure model is obtained. Fuzzy clustering method is used for vocabulary clustering and comprehensive retrieval in the virtual community of foreign language learning, the performance of vocabulary classification in foreign language learning is improved, the adaptive semantic information fusion method is used to realize the vocabulary data mining in the virtual community of foreign language learning, information retrieval and access scheduling for virtual communities in foreign language learning are realized based on data mining results. The simulation results show that the accuracy of foreign language vocabulary retrieval is good, improve the efficiency of foreign language learning.
