With the widespread applications of Massive Open Online Courses (MOOCs) platforms, an effective method is needed for personalized course recommendation. In view of the existing course recommendation methods, which usually use the course learning records to establish the overall static representation for users’ learning interests, while ignoring the dynamic changes of learning interests and users’ short-term learning interests, a Hierarchical and Phased Attention Network (HPAN) was proposed to carry out personalized course recommendation. In the first layer of the network, the attention network was used to obtain the user’s long- and short-term learning interests. In the second layer of the network, the user’s long- and short-term learning interests and short-term interaction sequence were combined to obtain the user’s interest vector through the attention network, then the preference value of the user’s interest vector with each course vector was calculated, and courses were recommended for the user according to the result. Experimental results on public dataset XuetangX show that, compared with the second best SHAN (Sequential Hierarchical Attention Network) model, HPAN model has the Recall@5 increased by 12.7%; compared with FPMC (Factorizing Personalized Markov Chains) model, HPAN model has the MRR@20 increased by 15.6%. HPAN model has better recommendation effect than the comparison models, and can be used for practical personalized course recommendation.
In Internet Protocol Television (IPTV) applications, a television terminal is usually shared by several family members. The exiting recommendation algorithms are difficult to analyze the different interests and preferences of family members from the historical data of terminal. In order to meet the video-on-demand requirements of multiple members under the same terminal, a capsule network-based IPTV video-on-demand recommendation model, namely CapIPTV, was proposed. Firstly, a user interest generation layer was designed on the basis of the capsule network routing mechanism, which took the historical behavior data of the terminal as the input, and the interest expressions of different family members were obtained through the clustering characteristic of the capsule network. Then, the attention mechanism was adopted to dynamically assign different attention weights to different interest expressions. Finally, the interest vector of different family members and the expression vector of video-on-demand were extracted, and the inner product of them was calculated to obtain the Top-N preference recommendation. Experimental results based on both the public dataset MovieLens and real radio and television dataset IPTV show that, the proposed CapIPTV outperforms the other 5 similar recommendation models in terms of Hit Rate (HR), Recall and Normalized Discounted Cumulative Gain (NDCG).
The current research of bilateral matching problem is limited to single-period scenario. Aiming at the issue, an approach was proposed to study matching decision problem under multi-period and multi-attribute. First, through the orness, a measurement of Agent's preference, an optimal program was constructed to determine the cumulative weight of an Agent within each attribute. More specifically, the criteria of this program consisted of two parts: one part was to minimize the sum of deviation between an orness and corresponding cumulative weight of an Agent in different period; another part was to minimize the maximum disparity among cumulative weights of an Agent. Then, based on obtained cumulative weight, matching degree which represented by Agent's positive and negative ideal between the cumulative evaluation value and perceived expectation can be determined via the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). Furthermore, a double-objective optimization model based on perceived expectation was constructed and the minimax method was used to solve this model for obtaining matching results. Finally, a numerical example was given to compare the minimax method with the linear weighting method. The results show that difference of profit and loss of utility obtained by the former method was 0.33, less than 0.36 that obtained by the latter method. Moreover, it also demonstrates the proposed method can maximize the profit and loss of utility of inferior side.
Since high-speed network traffic can not be effectively coped with the network traffic capture system implemented by software, and the multiple network flow need to be collected simultaneously to improve the capturing efficiency, an high-speed network flow capture framework in combination of hardware and software was presented, and the implementation of network traffic capture system based on NetFPGA-10G, called HSNTCS, was discussed. A variety of network flow in hardware was filtered and classified by the exact string matching engine and the regular expression matching engine of this system. After being transmitted to the corresponding data buffer at the driver layer, the network flow was directly copied to the corresponding database in user space. The experiments show that the throughput of UDP (User Datagram Protocol)and TCP (Transmission Control Protocol)in the high-speed network traffic capture system implemented by the hardware under the condition of exact string matching achieved 1.2Gb/s, which is about 3 times of that implemented by the software; and the throughput of UDP and TCP in the system implemented by the hardware under the condition of regular expression matching achieved 640Mb/s, which is about 3 times of that implemented by the software. The results demonstrate that the capture performance by the method of hardware is better than the method of software.