The transport property of electron through graphene-based double-barrier under a time periodic field is investigated. We study the influence of the system parameters and external field strength on the transmission pro...The transport property of electron through graphene-based double-barrier under a time periodic field is investigated. We study the influence of the system parameters and external field strength on the transmission probability. The results show that transmission exhibits various kinds of behavior with the change of parameters due to its angular anisotropy. One could control the values of transmission and conductivity as well as their distribution in each band by tuning the parameters.展开更多
In this study, a number of typical precursory anomalies recorded by stations in Qinghai, Gansu, Sichuan, Xinjiang, Ningxia, Hebei and Shaanxi provinces and autonomous regions before the Ms8.1 earthquake in the west of...In this study, a number of typical precursory anomalies recorded by stations in Qinghai, Gansu, Sichuan, Xinjiang, Ningxia, Hebei and Shaanxi provinces and autonomous regions before the Ms8.1 earthquake in the west of Kunlun Mountains Pass are collected and checked. According to the standards of earthquake cases in China, the criteria of the precursory anomalies are determined, and 53 distinguished. The characteristics of these anomalies before the Ms S. 1 earthquake are analyzed, with results showing a very large earthquake affected area. The precursory anomalies recorded by instruments were 2900 km away from the epicenter, and according to the study in this paper, reached 2100 km away. The results also show that the anomalies present characteristics of long duration, multi-measurement items and large-amplitude variation. The authors believe that in large earthquake monitoring, attention should be paid to the variation of data over a large area, ranging up to thousands kilometers, with much denser earthquake observation networks.展开更多
Generation of wind power time series is an important foundational task for assisting electric power system planning and mak- ing decision. By analyzing the characteristics of wind power persistence and variation, th!....Generation of wind power time series is an important foundational task for assisting electric power system planning and mak- ing decision. By analyzing the characteristics of wind power persistence and variation, th!.s paper proposes an improved Mar- kov chain Monte Carlo (MCMC) method, identified as the PV-MC method, for the direct generation of a synthetic series of wind power output. On the basis of the MCMC method, duration time and variation features are concluded in PV-MC method, gaining a more comprehensive reflection of wind power characteristics in the generated wind power time series. First, the wind power state series is generated to meet the state transition matrix based on the definition of the wind power state. Then, the time duration of each state in the series is determined by its respective duration character. Finally, the variation characteristic is used to convert the state series to a wind power time series. A significant amount of simulations are performed based on the PV-MC and MCMC methods and are then compared for 25 wind farms at 6 different locations throughout the world. The sim- ulation results show that the PV-MC method offers an excellent fit for the time domain features (persistence and variation characteristic) while holding other statistic features (mean value, variance, autocorrelation coefficient (ACC) and probability density function (PDF)) close to the MCMC method.展开更多
Objective: By applying moxibustion to the eight confluent points in different periods of time, to observe the changes in thermal pain threshold latency of acupoints based on Fei Teng Ba Fa. Methods: A total of 468 h...Objective: By applying moxibustion to the eight confluent points in different periods of time, to observe the changes in thermal pain threshold latency of acupoints based on Fei Teng Ba Fa. Methods: A total of 468 healthy college student volunteers received moxibustion at the eight confluent points in three different periods of time, i.e. Chen (7:00-9:00), Wu (11:00-13:00) and Xu (19:00-21:00). The thermal pain threshold latency was adopted to measure the changes in pain threshold of the eight confluent points under different conditions (different periods of time, different genders, different acupoints and different states of the acupoints) based on Fei Teng Ba Fa. Results: Finally, thirty subjects dropped out and 438 subjects were included. The comparison of thermal pain threshold latencies of the eight confluent points in the same opening or closing state based on Fei Teng Ba Fa: latencies of the closing points and adjunct points were significantly different in different periods of time (P〈0.05), the latencies of the males were significantly longer than those of the females (P〈0.05); there was no significant difference in the latency between the left and right sides (P〉0.05); in the female group, there was a significant difference in the latency between the lower-limb points and the upper-limb points (P〈0.05). The comparison of thermal point threshold latencies of the eight confluent points in different opening or closing state: in the period of Wu (11:00-13:00), the latencies of the opening points were significantly longer than those of the closing points and adjunct points (P〈0.05); for men, their opening and closing points had significantly longer thermal pain threshold latencies than their adjunct points (P〈0.05); despite the gender, the latencies of the upper limb opening and closing points were significantly longer than the latency of the adjunct points (P〈0.05); in the female group, the latencies of the lower-limb opening points were significantly shorter than those of the lower-limb closing and adjunct points (P〈0.05). Conclusion: Based on Fei Teng Ba Fa, the pain thresholds of the eight confluent points vary in different periods of time, gender, acupoint location and opening/closing state, which can be taken as the evidence of making time-based acu puncture-moxibustion prescriptions.展开更多
基金Supported in part by the National Natural Science Foundation of China under Grant Nos. 10775100, 10974137, 11047172, 11047020, and 11047173by the Fund of Nuclear Theory Center of HIRFL of China
文摘The transport property of electron through graphene-based double-barrier under a time periodic field is investigated. We study the influence of the system parameters and external field strength on the transmission probability. The results show that transmission exhibits various kinds of behavior with the change of parameters due to its angular anisotropy. One could control the values of transmission and conductivity as well as their distribution in each band by tuning the parameters.
基金funded by National Joint Foundation of Earthquake of China under Grant No.106086
文摘In this study, a number of typical precursory anomalies recorded by stations in Qinghai, Gansu, Sichuan, Xinjiang, Ningxia, Hebei and Shaanxi provinces and autonomous regions before the Ms8.1 earthquake in the west of Kunlun Mountains Pass are collected and checked. According to the standards of earthquake cases in China, the criteria of the precursory anomalies are determined, and 53 distinguished. The characteristics of these anomalies before the Ms S. 1 earthquake are analyzed, with results showing a very large earthquake affected area. The precursory anomalies recorded by instruments were 2900 km away from the epicenter, and according to the study in this paper, reached 2100 km away. The results also show that the anomalies present characteristics of long duration, multi-measurement items and large-amplitude variation. The authors believe that in large earthquake monitoring, attention should be paid to the variation of data over a large area, ranging up to thousands kilometers, with much denser earthquake observation networks.
基金supported by the National Natural Science Foundation of China(Grant No.51377027)the National Basic Research Program of China("973"Project)(Grant No.2012CB215104)ABB(China)Ltd
文摘Generation of wind power time series is an important foundational task for assisting electric power system planning and mak- ing decision. By analyzing the characteristics of wind power persistence and variation, th!.s paper proposes an improved Mar- kov chain Monte Carlo (MCMC) method, identified as the PV-MC method, for the direct generation of a synthetic series of wind power output. On the basis of the MCMC method, duration time and variation features are concluded in PV-MC method, gaining a more comprehensive reflection of wind power characteristics in the generated wind power time series. First, the wind power state series is generated to meet the state transition matrix based on the definition of the wind power state. Then, the time duration of each state in the series is determined by its respective duration character. Finally, the variation characteristic is used to convert the state series to a wind power time series. A significant amount of simulations are performed based on the PV-MC and MCMC methods and are then compared for 25 wind farms at 6 different locations throughout the world. The sim- ulation results show that the PV-MC method offers an excellent fit for the time domain features (persistence and variation characteristic) while holding other statistic features (mean value, variance, autocorrelation coefficient (ACC) and probability density function (PDF)) close to the MCMC method.
文摘Objective: By applying moxibustion to the eight confluent points in different periods of time, to observe the changes in thermal pain threshold latency of acupoints based on Fei Teng Ba Fa. Methods: A total of 468 healthy college student volunteers received moxibustion at the eight confluent points in three different periods of time, i.e. Chen (7:00-9:00), Wu (11:00-13:00) and Xu (19:00-21:00). The thermal pain threshold latency was adopted to measure the changes in pain threshold of the eight confluent points under different conditions (different periods of time, different genders, different acupoints and different states of the acupoints) based on Fei Teng Ba Fa. Results: Finally, thirty subjects dropped out and 438 subjects were included. The comparison of thermal pain threshold latencies of the eight confluent points in the same opening or closing state based on Fei Teng Ba Fa: latencies of the closing points and adjunct points were significantly different in different periods of time (P〈0.05), the latencies of the males were significantly longer than those of the females (P〈0.05); there was no significant difference in the latency between the left and right sides (P〉0.05); in the female group, there was a significant difference in the latency between the lower-limb points and the upper-limb points (P〈0.05). The comparison of thermal point threshold latencies of the eight confluent points in different opening or closing state: in the period of Wu (11:00-13:00), the latencies of the opening points were significantly longer than those of the closing points and adjunct points (P〈0.05); for men, their opening and closing points had significantly longer thermal pain threshold latencies than their adjunct points (P〈0.05); despite the gender, the latencies of the upper limb opening and closing points were significantly longer than the latency of the adjunct points (P〈0.05); in the female group, the latencies of the lower-limb opening points were significantly shorter than those of the lower-limb closing and adjunct points (P〈0.05). Conclusion: Based on Fei Teng Ba Fa, the pain thresholds of the eight confluent points vary in different periods of time, gender, acupoint location and opening/closing state, which can be taken as the evidence of making time-based acu puncture-moxibustion prescriptions.