This study proposed a random Smoothed Particle Hydrodynamics method for analyzing the post-failure behavior of landslides,which is based on the Karhunen-Loeve(K-L) expansion,the non-Newtonian fluid model,and the OpenM...This study proposed a random Smoothed Particle Hydrodynamics method for analyzing the post-failure behavior of landslides,which is based on the Karhunen-Loeve(K-L) expansion,the non-Newtonian fluid model,and the OpenMP parallel framework.Then,the applicability of this method was validated by comparing the generated random field with theoretical result and by simulating the post-failure process of an actual landslide.Thereafter,an illustrative landslide example was created and simulated to obtain the spatial variability effect of internal friction angle on the post-failure behavior of landslides under different coefficients of variation(COVs) and correlation lengths(CLs).As a conclusion,the reinforcement with materials of a larger friction angle can reduce the runout distance and impact the force of a landslide.As the increase of COV,the distribution range of influence zones also increases,which indicates that the deviation of influence zones becomes large.In addition,the correlation length in Monte Carlo simulations should not be too small,otherwise the variation range of influence zones will be underestimated.展开更多
We study the dynamical properties of heart rate variability （HRV） in sleep by analysing the scaling behaviour with the multifractal detrended fluctuation analysis method. It is well known that heart rate is regulate...We study the dynamical properties of heart rate variability （HRV） in sleep by analysing the scaling behaviour with the multifractal detrended fluctuation analysis method. It is well known that heart rate is regulated by the interaction of two branches of the autonomic nervous system： the parasympathetic and sympathetic nervous systems. By investigating the multifractal properties of light, deep, rapid-eye-movement （REM） sleep and wake stages, we firstly find an increasing multifractal behaviour during REM sleep which may be caused by augmented sympathetic activities relative to non-REM sleep. In addition, the investigation of long-range correlations of HRV in sleep with second order detrended fluctuation analysis presents irregular phenomena. These findings may be helpful to understand the underlying regulating mechanism of heart rate by autonomic nervous system during wake-sleep transitions.展开更多
Economic insufficiency causes stress and negative affects. Poverty is self-perpetuated, also due to a particular pattern of economic behaviors induced by negative affects and stress. Often, loneliness occurs together ...Economic insufficiency causes stress and negative affects. Poverty is self-perpetuated, also due to a particular pattern of economic behaviors induced by negative affects and stress. Often, loneliness occurs together with economic insufficiency. For this study, it has been selected a sample of convenience. A positive correlation between anxiety/depression and negative affects is presented. Dispositional optimism and social support, factors which contribute to health, serve as buffers, in negative correlation, of the negative impact of negative affects, due to financial restraint, on health. Financial management is negatively correlated with the lack of cardiovascular health, and cardiovascular dysfunction correlates positively with loneliness, in this study. Positive affects correlate positively with resilience skills, which correlate negatively with depression. Within this context, psychobiological therapeutic interventions and psychotherapy, which also target psychological dysfunction related to economic behavior of persons in a situation of poverty, would be beneficial.展开更多
互通式立交承担着不同方向交通流的流向转换功能,是道路交通网络的重要节点。目前高密度立交在城市道路网络中已愈发常见,高密度立交之间的间距比普通立交更小,车辆交织更为密集,驾驶人需要在更短的时间内进行分合流驾驶操作。为探究立...互通式立交承担着不同方向交通流的流向转换功能,是道路交通网络的重要节点。目前高密度立交在城市道路网络中已愈发常见,高密度立交之间的间距比普通立交更小,车辆交织更为密集,驾驶人需要在更短的时间内进行分合流驾驶操作。为探究立交间距对驾驶人精神负荷的影响与高密度立交出入口区段的驾驶人精神负荷统计特性,在重庆市内环快速路上选择了1段包含4座连续立交的路段作为实验对象,其中3座立交为高密度立交。通过车载仪器采集47名驾驶人在实车实验过程中的心电数据,对在高密度立交出入口区段与普通间距立交出入口区段的驾驶人心率变异性时域和频域指标进行差异性分析,得到了驾驶人在高密度立交与普通间距立交出入口区段的精神负荷分布特征。研究结果表明:驾驶人在经过普通间距立交出入口区段和高密度立交出入口区段时的心率变异性时域指标不存在显著性差异,频域指标心率变异性的低、高频功率的比值(ratio of low-frequency to high-frequency,LF/HF)存在显著性差异,频域指标LF/HF可作为评价驾驶人精神负荷在立交出入口区段的主要指标;驾驶人在经过高密度立交入口区段时,频域指标LF/HF比经过普通间距立交入口区段时显著增加,立交间距不足会增加驾驶人在立交入口区段的精神负荷;驾驶人在经过普通间距立交出口区段时的心率变异性频域指标LF/HF比经过高密度立交出口区段时显著增加,即驾驶人通过普通间距立交出口区段的精神负荷更大;对于高密度立交群,驾驶人在入口区段的精神负荷水平要略高于出口区段。展开更多
This study clarified the characteristic autonomic nervous activity of institutionalized elders diagnosed with dementia using Hasegawa’s Dementia Scale-Revised. Twenty-six healthy adult persons (HPs) in their 20 s - 4...This study clarified the characteristic autonomic nervous activity of institutionalized elders diagnosed with dementia using Hasegawa’s Dementia Scale-Revised. Twenty-six healthy adult persons (HPs) in their 20 s - 40 s met the inclusion criteria, and 16 persons (27.6 ± 8.2 years old) completed the research procedure. Of 70 persons with dementia (PDs) residing at the one geriatric health services facilities, only 24 persons met the inclusion criteria, and only nine (N = 9, 83.44 ± 9.45 years old) completed the procedure. Actigraph and ambulatory electrocardiographic instruments measuring autonomic nervous activity were attached to the subjects for 24 hours. Activities and behaviors of PDs and HPs were observed by clinically experienced staff nurses and care workers. High frequency (HF) power indicating parasympathetic activity and LF/HF ratio indicating sympathetic activity were calculated. When awake, PDs’ LF/HF ratio was significantly lower than HP’s (Z = -2.60, p < 0.01), showing significant differences in the LF/HF ratios between waking and sleeping, more than those of the PDs (p < 0.001). Similarly, when awake, significant positive correlations were observed in the LF/HF ratio and actigraph activity count (AC) in 11 HPs and 3 PDs (range r = 0.17 to 0.49, p < 0.05);however, significant negative correlation was found in HF and AC of 12 HPs and 3 PDs (range r = -0.55 to -0.18, p < 0.05). While sleeping, significant positive correlations were observed in LF/HF and AC of 3 HPs and 1 PD (range r = 0.35 to 0.42, p < 0.05) and significant negative correlation was found in the HF and AC of 1 HP (r= -0.32, p < 0.001) and 1 PD (r = -0.32, p < 0.05). The mean value of LF/HF in a wakeful state was significantly lower for PDs than HPs. Combined results of behavioral observation, actigrapy and heart rate variability (HRV) analyses suggested that PDs showed positive correlations between LF/HF and AC in a wakeful state. Compared to those who showed no positive correlation, they did not require much nursing care.展开更多
基金This work is supported by the Natural Science Foundation of China(NSFC Grant No.51808192,51879091,41630638)the Natural Science Foundation of Jiangsu Province(Grant No.BK20170887)the China Postdoctoral Science Foundation(Grant Nos.2017M611673 and 2018T110432).We thank Ms.Ruihua Yu for her contribution in compiling some of the figures in this work.
文摘This study proposed a random Smoothed Particle Hydrodynamics method for analyzing the post-failure behavior of landslides,which is based on the Karhunen-Loeve(K-L) expansion,the non-Newtonian fluid model,and the OpenMP parallel framework.Then,the applicability of this method was validated by comparing the generated random field with theoretical result and by simulating the post-failure process of an actual landslide.Thereafter,an illustrative landslide example was created and simulated to obtain the spatial variability effect of internal friction angle on the post-failure behavior of landslides under different coefficients of variation(COVs) and correlation lengths(CLs).As a conclusion,the reinforcement with materials of a larger friction angle can reduce the runout distance and impact the force of a landslide.As the increase of COV,the distribution range of influence zones also increases,which indicates that the deviation of influence zones becomes large.In addition,the correlation length in Monte Carlo simulations should not be too small,otherwise the variation range of influence zones will be underestimated.
基金Supported by the National Science Foundation of China under Grant Nos 60471057 and 70571075, and the Foundation for Graduate Student of USTC under Grant No KD2006046.
文摘We study the dynamical properties of heart rate variability （HRV） in sleep by analysing the scaling behaviour with the multifractal detrended fluctuation analysis method. It is well known that heart rate is regulated by the interaction of two branches of the autonomic nervous system： the parasympathetic and sympathetic nervous systems. By investigating the multifractal properties of light, deep, rapid-eye-movement （REM） sleep and wake stages, we firstly find an increasing multifractal behaviour during REM sleep which may be caused by augmented sympathetic activities relative to non-REM sleep. In addition, the investigation of long-range correlations of HRV in sleep with second order detrended fluctuation analysis presents irregular phenomena. These findings may be helpful to understand the underlying regulating mechanism of heart rate by autonomic nervous system during wake-sleep transitions.
文摘Economic insufficiency causes stress and negative affects. Poverty is self-perpetuated, also due to a particular pattern of economic behaviors induced by negative affects and stress. Often, loneliness occurs together with economic insufficiency. For this study, it has been selected a sample of convenience. A positive correlation between anxiety/depression and negative affects is presented. Dispositional optimism and social support, factors which contribute to health, serve as buffers, in negative correlation, of the negative impact of negative affects, due to financial restraint, on health. Financial management is negatively correlated with the lack of cardiovascular health, and cardiovascular dysfunction correlates positively with loneliness, in this study. Positive affects correlate positively with resilience skills, which correlate negatively with depression. Within this context, psychobiological therapeutic interventions and psychotherapy, which also target psychological dysfunction related to economic behavior of persons in a situation of poverty, would be beneficial.
文摘互通式立交承担着不同方向交通流的流向转换功能,是道路交通网络的重要节点。目前高密度立交在城市道路网络中已愈发常见,高密度立交之间的间距比普通立交更小,车辆交织更为密集,驾驶人需要在更短的时间内进行分合流驾驶操作。为探究立交间距对驾驶人精神负荷的影响与高密度立交出入口区段的驾驶人精神负荷统计特性,在重庆市内环快速路上选择了1段包含4座连续立交的路段作为实验对象,其中3座立交为高密度立交。通过车载仪器采集47名驾驶人在实车实验过程中的心电数据,对在高密度立交出入口区段与普通间距立交出入口区段的驾驶人心率变异性时域和频域指标进行差异性分析,得到了驾驶人在高密度立交与普通间距立交出入口区段的精神负荷分布特征。研究结果表明:驾驶人在经过普通间距立交出入口区段和高密度立交出入口区段时的心率变异性时域指标不存在显著性差异,频域指标心率变异性的低、高频功率的比值(ratio of low-frequency to high-frequency,LF/HF)存在显著性差异,频域指标LF/HF可作为评价驾驶人精神负荷在立交出入口区段的主要指标;驾驶人在经过高密度立交入口区段时,频域指标LF/HF比经过普通间距立交入口区段时显著增加,立交间距不足会增加驾驶人在立交入口区段的精神负荷;驾驶人在经过普通间距立交出口区段时的心率变异性频域指标LF/HF比经过高密度立交出口区段时显著增加,即驾驶人通过普通间距立交出口区段的精神负荷更大;对于高密度立交群,驾驶人在入口区段的精神负荷水平要略高于出口区段。
文摘This study clarified the characteristic autonomic nervous activity of institutionalized elders diagnosed with dementia using Hasegawa’s Dementia Scale-Revised. Twenty-six healthy adult persons (HPs) in their 20 s - 40 s met the inclusion criteria, and 16 persons (27.6 ± 8.2 years old) completed the research procedure. Of 70 persons with dementia (PDs) residing at the one geriatric health services facilities, only 24 persons met the inclusion criteria, and only nine (N = 9, 83.44 ± 9.45 years old) completed the procedure. Actigraph and ambulatory electrocardiographic instruments measuring autonomic nervous activity were attached to the subjects for 24 hours. Activities and behaviors of PDs and HPs were observed by clinically experienced staff nurses and care workers. High frequency (HF) power indicating parasympathetic activity and LF/HF ratio indicating sympathetic activity were calculated. When awake, PDs’ LF/HF ratio was significantly lower than HP’s (Z = -2.60, p < 0.01), showing significant differences in the LF/HF ratios between waking and sleeping, more than those of the PDs (p < 0.001). Similarly, when awake, significant positive correlations were observed in the LF/HF ratio and actigraph activity count (AC) in 11 HPs and 3 PDs (range r = 0.17 to 0.49, p < 0.05);however, significant negative correlation was found in HF and AC of 12 HPs and 3 PDs (range r = -0.55 to -0.18, p < 0.05). While sleeping, significant positive correlations were observed in LF/HF and AC of 3 HPs and 1 PD (range r = 0.35 to 0.42, p < 0.05) and significant negative correlation was found in the HF and AC of 1 HP (r= -0.32, p < 0.001) and 1 PD (r = -0.32, p < 0.05). The mean value of LF/HF in a wakeful state was significantly lower for PDs than HPs. Combined results of behavioral observation, actigrapy and heart rate variability (HRV) analyses suggested that PDs showed positive correlations between LF/HF and AC in a wakeful state. Compared to those who showed no positive correlation, they did not require much nursing care.
