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Zhang D.-S.,Heilongjiang University | Zhang D.-S.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | Li J.-B.,Heilongjiang University | Li J.-B.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | And 2 more authors.
Tongxin Xuebao/Journal on Communications | Year: 2011

Aiming at triple hidden terminal problems in wireless sensor networks, an adaptive duty cycle based multi-channel MAC protocol was proposed, called MCR. MCR efficiently handled triple hidden terminal problems with multiple channel reservation. By minimizing the lower bound of average times of channel switching in MCR, the optimal duty cycle in theoretical analysis was obtained. To investigate values of multiple channel reservation and dynamic duty cycling in MCR, extensive simulation and real testbed experiments were conducted. The results show that compared with other protocols, when the number of channels is larger or loads are heavy, M-cube improves throughput and energy efficiency significantly.


Qin Q.,Heilongjiang University | Tan L.,Heilongjiang University | Tan L.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2016

As processed data is relatively dense or the support is small in weighted frequent patterns mining process, the number of frequent patterns which meet the conditions will be exponential growth, and mining all frequent patterns will need too much computation. Hence, mining the maximal weighted frequent patterns containing all frequent patterns has less calculation, and it has more utility value. Aiming at the process of maximal weighted frequent patterns mining, an efficient algorithm, based on WIdT-Trees, is proposed to discover maximal weighted frequent patterns. In the algorithm, WIdT-Tree is optimized from WIT-Tree. The dTidset strategy is used to calculate the weighted support of frequent k-itemsets, and the nodes with equal extended weighted support are pruned off in order to reduce the computational cost and decrease the search space complexity. Algorithms are tested and compared on real and synthetic datasets and experimental results show that our algorithm is more efficient and scalable. © Springer International Publishing AG 2016.


Zhang D.-S.,Heilongjiang University | Zhang D.-S.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | Li J.-B.,Heilongjiang University | Li J.-B.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | And 2 more authors.
Ruan Jian Xue Bao/Journal of Software | Year: 2012

To tackle control channel saturation and triple hidden terminal problems, this paper proposes RIM, a receiver-initiated multi-channel MAC protocol with duty cycling for WSNs. By adopting a receiver-initiated transmission scheme and probability-based random channel selection, RIM effectively alleviates, if not completely eliminates, control channel saturation and triple hidden terminal problems. In addition, RIM exploits a simple but reliable asynchronous broadcast scheme to solve the problem of broadcast data loss with reliable broadcast-intensive applications. More importantly, RIM is fully distributed with no requirements of time synchronization or multi-radio. Therefore, RIM is very easily implemented in resource-constrained sensor nodes. Via the theoretical analysis, the optimal duty cycle are obtained, respectively. The simulation and real testbed experimental results show that RIM achieves significant improvement in energy efficiency with increasing benefit when the number of channels and traffic loads increase, while maintaining higher throughput. Moreover, RIM exhibits a prominent ability to enhance its broadcast reliability. © 2012 ISCAS.


Guo Y.-H.,Heilongjiang University | Wang X.,Heilongjiang University | Wang X.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province
Xitong Gongcheng Lilun yu Shijian/System Engineering Theory and Practice | Year: 2011

In order to improve the network spatial reuse and maximize the network throughput, this paper presents a physical conflict model based power allocation and link scheduling algorithm (PPLA). Firstly, PPLA picks available set of parallel links using hexagon coloring method. With physical conflict model, it further obtains the minimum power vector which corresponds to parallel links set. The experimental results indicate that the algorithm can increase network spatial reuse ratio and improve throughput significantly.


Jia B.,Heilongjiang University | Li J.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province
Communications in Computer and Information Science | Year: 2015

To overcome the defects that previous research cannot recognize human activities accurately in real-time, we proposed a novel method, which collects data from the accelerator and gyroscope on a mobile phone, and then extracts features of both time domain and frequency domain. These features are used to learn random forest models offline, which make our mobile app can recognize human activities accurately online in real-time. Verified by theoretical analysis and a large number of contrast experiments, the recognition is rapid and accurate on mobile phones with accuracy at 97%. © Springer-Verlag Berlin Heidelberg 2015.


Wan K.,Heilongjiang University | Lu J.,Heilongjiang University | Lu J.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | Zheng J.,Heilongjiang University | Ren Z.,Heilongjiang University
Communications in Computer and Information Science | Year: 2016

The parallel algorithm of the evolutionary distance between different species is implemented by using OpenMP parallel technique in this paper. In order to get the best degree of algorithm parallelism, the method of making loop variable corresponding to the rower and column labels of distance matrix is adopted. It is to say that the double loop can be converted into single loop to improve the parallel efficiency. The serial algorithm and parallel algorithm are compared in this paper. The experiment result shows that the highest speedup is 14.1. It improves the running efficiency of the program. It is a great significance to dealing with massive bioinformatics data. © Springer Science+Business Media Singapore 2016.


Ni L.-Y.,Heilongjiang University | Ni L.-Y.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | Li J.-B.,Heilongjiang University | Li J.-B.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province
Ruan Jian Xue Bao/Journal of Software | Year: 2014

To address the problems of transmission delay, transmission conflicts and low throughput in Wireless sensor networks, this paper proposes a channel allocation and routing strategy in Multi-Radio Multi-Channel Networks. The strategy is to dynamically establish a k-ary n-cube topology. It not only uses the optimal static channel allocation algorithm to improve the throughput of nodes but also employs the dimension order routing algorithm to reduce transmission conflicts. This method is suitable for the network of density nodes with many communication conflicts. It can also be used in both single hop and multi hop network environment. The experiment results show that compared with traditional methods, the channel allocation and routing strategy based on the k-ary n-cube topology can effectively reduce end to end delay, network conflicts and energy consumption, prolong the network lifetime and increase the throughput of network. ©2014 ISCAS.


Li J.,Heilongjiang University | Lu J.,Heilongjiang University | Lu J.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | Jing R.,Heilongjiang University | And 2 more authors.
Proceedings of 2015 IEEE Advanced Information Technology, Electronic and Automation Control Conference, IAEAC 2015 | Year: 2015

Soybean genotypes are adopted as the data source and the Tajima's D statistical method is parallel implemented by OpenMP technology. This method is used for testing neutral mutation hypothesis of DNA polymorphism. By setting the sliding window size, all chromosomes containing the massive windows with multiple SNP sites are parallel processed, then the number of individual in sample, the number of segregating sites (S) and average number of nucleotide differences (n) are obtained. After parameters filtering, the Tajima's D values for the effective SNP sites in each sliding window are parallel calculated. According to the experimental data, the serial/parallel algorithms are compared and the conclusion shows that the efficiency of testing neutral mutation can be improved by using the OpenMP technology. It is a realistic significance for processing massive biological information data. © 2015 IEEE.


Zhang H.,Heilongjiang University | Yang Y.,Heilongjiang University | Yang Y.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | Zhang Z.,Heilongjiang University | Zhang Z.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province
Communications in Computer and Information Science | Year: 2016

As location-based social network (LBSN) services become more popular in people’s lives, Point of Interest (POI) recommendation has become an important research topic.POI recommendation is to recommend places where users have not visited before. There are two problems in POI recommendation: sparsity and precision. Most users only check-in a few POIs in an LBSN. To tackle the sparse problem in a certain extent, we compute the similarity between the check-in datasets of different times. For the precision problem, we incorporate temporal information and geographical information. The temporal information will influence how the user chooses and allow the user to visit different distance point on different day. The geographical information is also used as a control for points which are too far away from the user’s check-in data. Our experimental results on real life LBSN datasets show that the proposed approach outperforms the other POI recommendation methods substantially. © Springer Science+Business Media Singapore 2016.


Huang W.,Heilongjiang University | Ma J.,Heilongjiang University | Ma J.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province | Zhang E.,Heilongjiang University | Zhang E.,Key Laboratory of Database and Parallel Computing of Heilongjiang Province
Communications in Computer and Information Science | Year: 2016

A new Gaussian mixture model is used to improve the quality of propagation method for SFS in this paper. The improved algorithm can overcome most difficulties of propagation SFS method including slow convergence, interdependence of propagation nodes and error accumulation. To slow convergence and interdependence of propagation nodes, stable propagation source and integration path are used to make sure that the reconstruction work of each pixel in the image is independent. A Gaussian mixture model based on prior conditions is proposed to fix the error of integration. Good result has been achieved in the experiment for Lambert composite image of the front illumination. © Springer Science+Business Media Singapore 2016.

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