Relative clock demonstrates the endogenous heterogeneity of human dynamics

The heavy-tailed inter-event time distributions are widely observed in many human-activated systems, which may result from both endogenous mechanisms like the highest-priority-first protocol and exogenous factors like the varying global activity versus time. To distinguish the effects on temporal statistics from different mechanisms is this of theoretical significance. In this Letter, we propose a new timing method by using a relative clock, where the time length between two consecutive events of an individual is counted as the number of other individuals' events appeared during this interval. We propose a model, in which agents act either in a constant rate or with a power-law inter-event time distribution, and the global activity either keeps unchanged or varies periodically versus time. Our analysis shows that the heavy tails caused by the heterogeneity of global activity can be eliminated by setting the relative clock, yet the heterogeneity due to real individual behaviors still exists. We perform extensive experiments on four large-scale systems, the search engine by AOL, a social bookmarking system--Delicious, a short-message communication network, and a microblogging system--Twitter. Strong heterogeneity and clear seasonality of global activity are observed, but the heavy tails cannot be eliminated by using the relative clock. Our results suggest the existence of endogenous heterogeneity of human dynamics.Comment: 6 pages 7 figures 2 Table

Studies on Epidemiology and Prediction of Soybean Mosaic Virus

-Some epidemiological factors of SMV were studied in Jinan, Shandong Province from 1984 to 1989. The results indicated that the resistance of soybean cultivars and the amount of primary inoculum sources dominated the dynamic aspects of SMV epidemics. It wOriginating text in Chinese.Citation: Luo, Ruiwu, Shang, Youfen, Yang, Chongliang, Zhao, Jiuhua, Li, Changsong. (1991). Studies on Epidemiology and Prediction of Soybean Mosaic Virus. Journal of Plant Protection / Acta Phytophylacica Sinica, 18(3), 267-271

Multi-level Attention Model for Weakly Supervised Audio Classification

In this paper, we propose a multi-level attention model to solve the weakly labelled audio classification problem. The objective of audio classification is to predict the presence or absence of audio events in an audio clip. Recently, Google published a large scale weakly labelled dataset called Audio Set, where each audio clip contains only the presence or absence of the audio events, without the onset and offset time of the audio events. Our multi-level attention model is an extension to the previously proposed single-level attention model. It consists of several attention modules applied on intermediate neural network layers. The output of these attention modules are concatenated to a vector followed by a multi-label classifier to make the final prediction of each class. Experiments shown that our model achieves a mean average precision (mAP) of 0.360, outperforms the state-of-the-art single-level attention model of 0.327 and Google baseline of 0.314.Comment: 5 pages, 3 figures, Submitted to Eusipco 201

Study on MPGA-BP of Gravity Dam Deformation Prediction

Displacement is an important physical quantity of hydraulic structures deformation monitoring, and its prediction accuracy is the premise of ensuring the safe operation. Most existing metaheuristic methods have three problems: (1) falling into local minimum easily, (2) slowing convergence, and (3) the initial value’s sensitivity. Resolving these three problems and improving the prediction accuracy necessitate the application of genetic algorithm-based backpropagation (GA-BP) neural network and multiple population genetic algorithm (MPGA). A hybrid multiple population genetic algorithm backpropagation (MPGA-BP) neural network algorithm is put forward to optimize deformation prediction from periodic monitoring surveys of hydraulic structures. This hybrid model is employed for analyzing the displacement of a gravity dam in China. The results show the proposed model is superior to an ordinary BP neural network and statistical regression model in the aspect of global search, convergence speed, and prediction accuracy

Study on Biology and Control of Aphis Glycines

Results of laboratory and field experiments showed that Aphis glycines could reproduce 18-22 generations per year in Jinan, and that generation period, reproductive period and reproduction rate were dependent on temperature. The aphids migrated with two peaks -- in the first ten days of June and between the last ten days of July and first ten days of August. The insect population on soybean plants was low during seedling stage and peaked in the first ten days of August. The aphid was controlled effectively by furrow application of carbofuran (Furaden) and aldicarb (Temik) and by spray application of omethoate (Dimethoate - met) and fenvalerate (Sumicidin).Originating text in Chinese.Citation: Li, Changsong, Luo, Ruiwu, Yang, Congliang, Shang, Youfen, Zhao, Jiuhua, Xin, Xiangqi. (2000). Study on Biology and Control of Aphis Glycines. Soybean Science, 19(4), 337-340