In this paper, we have studied the waveforms of background noise in a seismograph and set up an AR model to characterize them. We then complete the modeling and the automatic recognition program. Finally, we provide t...In this paper, we have studied the waveforms of background noise in a seismograph and set up an AR model to characterize them. We then complete the modeling and the automatic recognition program. Finally, we provide the results from automatic recognition and the manual recognition of the first motion for 25 underground explosions.展开更多
Based on the data of first motion of 11 earthquake sequences with ML ≥ 3.0 recorded by the Telemetric Seismic Network of Shanxi since the 1980s, the first motion characteristics of each earthquake sequence were studi...Based on the data of first motion of 11 earthquake sequences with ML ≥ 3.0 recorded by the Telemetric Seismic Network of Shanxi since the 1980s, the first motion characteristics of each earthquake sequence were studied. It is known that earthquake sequences of different types have different consistency characteristics of focal mechanism. The decrease and increase of the first motion contradictory sign ratios could be taken as an index to judge whether there would still be a larger earthquake to come after the earthquake sequence.展开更多
This paper investigates a new formation motion problem of a class of first-order multi-agent systems with antagonistic interactions.A distributed formation control algorithm is proposed for each agent to realize the a...This paper investigates a new formation motion problem of a class of first-order multi-agent systems with antagonistic interactions.A distributed formation control algorithm is proposed for each agent to realize the antagonistic formation motion.A sufficient condition is derived to ensure that all of the agents make an antagonistic formation motion in a distributed manner.It is shown that all of the agents can be spontaneously divided into several groups and that agents in the same group collaborate while agents in different groups compete.Finally,a numerical simulation is included to demonstrate our theoretical results.展开更多
In this paper, we are concerned with Re?ected Geometric Brownian Motion (RGBM) with two barriers. And the stationary distribution of RGBM is derived by Markovian in?nitesimal Generator method. Consequently the ?rst pa...In this paper, we are concerned with Re?ected Geometric Brownian Motion (RGBM) with two barriers. And the stationary distribution of RGBM is derived by Markovian in?nitesimal Generator method. Consequently the ?rst passage time of RGBM is also discussed.展开更多
Let h(t) be a smooth function, Bt a standard Brownian motion and th=inf{t;Bt=h(t)} the first hitting time. In this paper, new formulations are derived to evaluate the probability density of the first hitting time. If ...Let h(t) be a smooth function, Bt a standard Brownian motion and th=inf{t;Bt=h(t)} the first hitting time. In this paper, new formulations are derived to evaluate the probability density of the first hitting time. If u(x, t) denotes the density function of x=Bt for t th, then uxx=2ut and u(h(t),t)=0. Moreover, the hitting time density dh(t) is 1/2ux(h(t),t). Applying some partial differential equation techniques, we derive a simple integral equation for dh(t). Two examples are demonstrated in this article.展开更多
This paper presents search model for a randomly moving target which follows truncated Brownian motion. The conditions that make the expected value of the first meeting time between the searcher and the target is finit...This paper presents search model for a randomly moving target which follows truncated Brownian motion. The conditions that make the expected value of the first meeting time between the searcher and the target is finite are given. We show the existence of an optimal strategy which minimizes this first meeting time.展开更多
This paper gives a characterization of a Hunt process path by the first exit left limit distribution. It is also showed that if the first exit left limit distribution leaving any ball from the center is a uniform dist...This paper gives a characterization of a Hunt process path by the first exit left limit distribution. It is also showed that if the first exit left limit distribution leaving any ball from the center is a uniform distribution on the sphere, then the Levy Processes are a scaled Brownian motion.展开更多
文摘In this paper, we have studied the waveforms of background noise in a seismograph and set up an AR model to characterize them. We then complete the modeling and the automatic recognition program. Finally, we provide the results from automatic recognition and the manual recognition of the first motion for 25 underground explosions.
文摘Based on the data of first motion of 11 earthquake sequences with ML ≥ 3.0 recorded by the Telemetric Seismic Network of Shanxi since the 1980s, the first motion characteristics of each earthquake sequence were studied. It is known that earthquake sequences of different types have different consistency characteristics of focal mechanism. The decrease and increase of the first motion contradictory sign ratios could be taken as an index to judge whether there would still be a larger earthquake to come after the earthquake sequence.
基金supported by the National Natural Science Foundation of China(Grant Nos.61203080 and 61473051)the Natural Science Foundation of Chongqing City(Grant No.CSTC 2011BB0081)
文摘This paper investigates a new formation motion problem of a class of first-order multi-agent systems with antagonistic interactions.A distributed formation control algorithm is proposed for each agent to realize the antagonistic formation motion.A sufficient condition is derived to ensure that all of the agents make an antagonistic formation motion in a distributed manner.It is shown that all of the agents can be spontaneously divided into several groups and that agents in the same group collaborate while agents in different groups compete.Finally,a numerical simulation is included to demonstrate our theoretical results.
文摘In this paper, we are concerned with Re?ected Geometric Brownian Motion (RGBM) with two barriers. And the stationary distribution of RGBM is derived by Markovian in?nitesimal Generator method. Consequently the ?rst passage time of RGBM is also discussed.
文摘Let h(t) be a smooth function, Bt a standard Brownian motion and th=inf{t;Bt=h(t)} the first hitting time. In this paper, new formulations are derived to evaluate the probability density of the first hitting time. If u(x, t) denotes the density function of x=Bt for t th, then uxx=2ut and u(h(t),t)=0. Moreover, the hitting time density dh(t) is 1/2ux(h(t),t). Applying some partial differential equation techniques, we derive a simple integral equation for dh(t). Two examples are demonstrated in this article.
文摘This paper presents search model for a randomly moving target which follows truncated Brownian motion. The conditions that make the expected value of the first meeting time between the searcher and the target is finite are given. We show the existence of an optimal strategy which minimizes this first meeting time.
基金Supported by the National Natural Science Foundation of China (10601047)
文摘This paper gives a characterization of a Hunt process path by the first exit left limit distribution. It is also showed that if the first exit left limit distribution leaving any ball from the center is a uniform distribution on the sphere, then the Levy Processes are a scaled Brownian motion.