Gaussian colored noise induced spatial patterns and spatial coherence resonances in a square lattice neuronal network composed of Morris-Lecar neurons are studied.Each neuron is at resting state near a saddle-node bif...Gaussian colored noise induced spatial patterns and spatial coherence resonances in a square lattice neuronal network composed of Morris-Lecar neurons are studied.Each neuron is at resting state near a saddle-node bifurcation on invariant circle,coupled to its nearest neighbors by electronic coupling.Spiral waves with different structures and disordered spatial structures can be alternately induced within a large range of noise intensity.By calculating spatial structure function and signal-to-noise ratio(SNR),it is found that SNR values are higher when the spiral structures are simple and are lower when the spatial patterns are complex or disordered,respectively.SNR manifest multiple local maximal peaks,indicating that the colored noise can induce multiple spatial coherence resonances.The maximal SNR values decrease as the correlation time of the noise increases.These results not only provide an example of multiple resonances,but also show that Gaussian colored noise play constructive roles in neuronal network.展开更多
Objective To evaluate the feasibility and accuracy of measurement of myocardial perfusion defects with intravenous contrast-enhanced real-time three-dimensional echocardiography (CE-RT3DE). Methods RT3DE was performed...Objective To evaluate the feasibility and accuracy of measurement of myocardial perfusion defects with intravenous contrast-enhanced real-time three-dimensional echocardiography (CE-RT3DE). Methods RT3DE was performed in 21 open-chest mongrel dogs undergoing acute ligation of the left anterior descending artery (LAD, n=14) or distal branch of the left circumflex artery (LCX, n=7). A perfluorocarbon microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with Philips Sonos-7500 ultrasound system. Evans blue dye was injected into the occluded coronary artery for subsequent anatomic identification of underperfused myocardium. In vitro anatomic measurement of myocardial mass after removal of the animal’s heart was regarded as the control. Blinded off-line calculation of left ventricular mass and perfusion defect mass from RT3DE images were performed using an interactive aided-manual tracing technique.Results Total left ventricular (LV) myocardial mass ranged from 38.9 to 78.5 (mean±SD: 60.0±10.1) g. The mass of perfusion defect ranged from 0 to 21.4 (mean±SD: 12.0±5.0) g or 0 to 27% of total LV mass (mean±SD: 19%±6%). The RT3DE estimation of total LV mass (mean±SD: 59.8±9.9 g) strongly correlated with the anatomic measurement (r=0.98; y=2.01+0.96x). The CE-RT3DE calculation of the mass of underperfused myocardium (mean±SD: 12.3±5.3 g) also strongly correlated with the anatomic measurement (r=0.96; y=-0.10+1.04x) and when expressed as percentage of total LV mass (r=0.95; y=-0.20+1.04x). Conclusions RT3DE with myocardial contrast opacification could accurately estimate underperfused myocardial mass in dogs of acute coronary occlusion and would play an important role in quantitative assessment of myocardial perfusion defects in patients with coronary artery disease.展开更多
The nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation is analytically investigated by using the formally variable separation approach. New analytical solutions for the governing e...The nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation is analytically investigated by using the formally variable separation approach. New analytical solutions for the governing equation of this system have been obtained for dust acoustic waves in a dust plasma for the first time. We derive exact analytical expressions for the general case of the nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation.展开更多
The paper takes the relation between soundscapes and power struggles as its problem area and focuses on the role of music that is performed in public protests. It argues that music and street performances are conceive...The paper takes the relation between soundscapes and power struggles as its problem area and focuses on the role of music that is performed in public protests. It argues that music and street performances are conceived and therefore utilised as sonic acts of political struggle in urban realm. Starting with a general understanding of hearing mechanisms, the study elucidates the relationships among territoriality of soundscape, identity construction, social segregation and polarisation, and finally, power struggle. Within the framework of the intersection area of these concepts, the paper discusses the processes of politisation of soundscape through music as a form of protest event that is performed in public realm. Throughout the paper, it is focused on the significant cases of public protests as well as political events that occured in public space. The main emphasis is on the use of sound technologies to impose power on masses of people. The paper tackles the question of how the salient characteristics of soundscape are sonically adopted as means for counter-political acts in public realm.展开更多
In this paper, we study a fluctuating potential barrier system with correlated spatial noises. Study shows that for this system, there is the resonant activation over the fluctuating potential barrier, and that the co...In this paper, we study a fluctuating potential barrier system with correlated spatial noises. Study shows that for this system, there is the resonant activation over the fluctuating potential barrier, and that the correlation between the different spatial noises can enhance (or weaken) the resonant activation.展开更多
In the territory of Poland the manner of urban space management is defined by a planning document called LLUP （local land use plan）. When analyzing the development process of Polish cities, an obvious conclusion eme...In the territory of Poland the manner of urban space management is defined by a planning document called LLUP （local land use plan）. When analyzing the development process of Polish cities, an obvious conclusion emerges about the lack of complex studies and researches of the environment concerning the issue of acoustic climate. The procedures of development of local land use plan involve merely a general diagnosis of an environment excluding measured values of pollution, including noise levels. The main aim of this article is to introduce the issue of the influence that acoustic climate has on the urban space planning with the application of SNM （strategic noise mapping）. The map enables holistic assessment of the degree to which urban areas are exposed to noise, determines its sources and forecasts variations of its levels. Preliminary research results confirmed the necessity of including noise level influence in the procedures related to urban space planning especially concerning its forecasted levels resulting from estimates of local land use plans. Applying SNM in verification of conceptual space arrangements in terms of protection against noise in the preparation of LLUP as well as their further application in the plan is a considerable advantage.展开更多
Intensity of cavitation is significant in ultrasonic wastewater treatment,but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different...Intensity of cavitation is significant in ultrasonic wastewater treatment,but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different powers of 495 kHz ultrasonic are measured in experiment in comparison with conductimetric method.Simulation results show that time difference and electrical conductivity are both approximately positive proportional to the ultrasonic power.The degradation of PNP solution verifies the availability in wastewater treatment by using ultrasonic.展开更多
基金Supported by National Natural Science Foundation of China under Grant Nos. 11072135 and 10772101the Fundamental Research Funds for the Central Universities under Grant No. GK200902025
文摘Gaussian colored noise induced spatial patterns and spatial coherence resonances in a square lattice neuronal network composed of Morris-Lecar neurons are studied.Each neuron is at resting state near a saddle-node bifurcation on invariant circle,coupled to its nearest neighbors by electronic coupling.Spiral waves with different structures and disordered spatial structures can be alternately induced within a large range of noise intensity.By calculating spatial structure function and signal-to-noise ratio(SNR),it is found that SNR values are higher when the spiral structures are simple and are lower when the spatial patterns are complex or disordered,respectively.SNR manifest multiple local maximal peaks,indicating that the colored noise can induce multiple spatial coherence resonances.The maximal SNR values decrease as the correlation time of the noise increases.These results not only provide an example of multiple resonances,but also show that Gaussian colored noise play constructive roles in neuronal network.
文摘Objective To evaluate the feasibility and accuracy of measurement of myocardial perfusion defects with intravenous contrast-enhanced real-time three-dimensional echocardiography (CE-RT3DE). Methods RT3DE was performed in 21 open-chest mongrel dogs undergoing acute ligation of the left anterior descending artery (LAD, n=14) or distal branch of the left circumflex artery (LCX, n=7). A perfluorocarbon microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with Philips Sonos-7500 ultrasound system. Evans blue dye was injected into the occluded coronary artery for subsequent anatomic identification of underperfused myocardium. In vitro anatomic measurement of myocardial mass after removal of the animal’s heart was regarded as the control. Blinded off-line calculation of left ventricular mass and perfusion defect mass from RT3DE images were performed using an interactive aided-manual tracing technique.Results Total left ventricular (LV) myocardial mass ranged from 38.9 to 78.5 (mean±SD: 60.0±10.1) g. The mass of perfusion defect ranged from 0 to 21.4 (mean±SD: 12.0±5.0) g or 0 to 27% of total LV mass (mean±SD: 19%±6%). The RT3DE estimation of total LV mass (mean±SD: 59.8±9.9 g) strongly correlated with the anatomic measurement (r=0.98; y=2.01+0.96x). The CE-RT3DE calculation of the mass of underperfused myocardium (mean±SD: 12.3±5.3 g) also strongly correlated with the anatomic measurement (r=0.96; y=-0.10+1.04x) and when expressed as percentage of total LV mass (r=0.95; y=-0.20+1.04x). Conclusions RT3DE with myocardial contrast opacification could accurately estimate underperfused myocardial mass in dogs of acute coronary occlusion and would play an important role in quantitative assessment of myocardial perfusion defects in patients with coronary artery disease.
文摘The nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation is analytically investigated by using the formally variable separation approach. New analytical solutions for the governing equation of this system have been obtained for dust acoustic waves in a dust plasma for the first time. We derive exact analytical expressions for the general case of the nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation.
文摘The paper takes the relation between soundscapes and power struggles as its problem area and focuses on the role of music that is performed in public protests. It argues that music and street performances are conceived and therefore utilised as sonic acts of political struggle in urban realm. Starting with a general understanding of hearing mechanisms, the study elucidates the relationships among territoriality of soundscape, identity construction, social segregation and polarisation, and finally, power struggle. Within the framework of the intersection area of these concepts, the paper discusses the processes of politisation of soundscape through music as a form of protest event that is performed in public realm. Throughout the paper, it is focused on the significant cases of public protests as well as political events that occured in public space. The main emphasis is on the use of sound technologies to impose power on masses of people. The paper tackles the question of how the salient characteristics of soundscape are sonically adopted as means for counter-political acts in public realm.
文摘In this paper, we study a fluctuating potential barrier system with correlated spatial noises. Study shows that for this system, there is the resonant activation over the fluctuating potential barrier, and that the correlation between the different spatial noises can enhance (or weaken) the resonant activation.
文摘In the territory of Poland the manner of urban space management is defined by a planning document called LLUP （local land use plan）. When analyzing the development process of Polish cities, an obvious conclusion emerges about the lack of complex studies and researches of the environment concerning the issue of acoustic climate. The procedures of development of local land use plan involve merely a general diagnosis of an environment excluding measured values of pollution, including noise levels. The main aim of this article is to introduce the issue of the influence that acoustic climate has on the urban space planning with the application of SNM （strategic noise mapping）. The map enables holistic assessment of the degree to which urban areas are exposed to noise, determines its sources and forecasts variations of its levels. Preliminary research results confirmed the necessity of including noise level influence in the procedures related to urban space planning especially concerning its forecasted levels resulting from estimates of local land use plans. Applying SNM in verification of conceptual space arrangements in terms of protection against noise in the preparation of LLUP as well as their further application in the plan is a considerable advantage.
基金Supported by the National Natural Science Foundation of China(No.11274092,11274091,11304026)the Fundamental Research Funds for the Central Universities(No.14B10128)
文摘Intensity of cavitation is significant in ultrasonic wastewater treatment,but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different powers of 495 kHz ultrasonic are measured in experiment in comparison with conductimetric method.Simulation results show that time difference and electrical conductivity are both approximately positive proportional to the ultrasonic power.The degradation of PNP solution verifies the availability in wastewater treatment by using ultrasonic.
