This paper proposes a method for simulation of non-stationary ground motion processes having the identical statistical feature, time-dependent power spectrum, with a given ground motion record, on the basis of review ...This paper proposes a method for simulation of non-stationary ground motion processes having the identical statistical feature, time-dependent power spectrum, with a given ground motion record, on the basis of review of simulation of non-stationary ground motion processes. The method has the following advantages: the sample processes are non-stationary both in amplitude and frequency, and both the amplitude and frequency non-stationarity depend on the target power spectrum; the power spectrum of any sample process does not necessarily accord with the target power spectrum, but statistically, it strictly accords with the target power spectrum. Finally, the method is verified by simulation of one acceleration record in Landers earthquake.展开更多
This paper proposes a method for simulation of non-stationary ground motion processes having the identical statis-tical feature, time-dependent power spectrum, with a given ground motion record, on the basis of review...This paper proposes a method for simulation of non-stationary ground motion processes having the identical statis-tical feature, time-dependent power spectrum, with a given ground motion record, on the basis of review of simu-lation of non-stationary ground motion processes. The method has the following advantages: the sample processes are non-stationary both in amplitude and frequency, and both the amplitude and frequency non-stationarity depend on the target power spectrum; the power spectrum of any sample process does not necessarily accord with the tar-get power spectrum, but statistically, it strictly accords with the target power spectrum. Finally, the method is veri-fied by simulation of one acceleration record in Landers earthquake.展开更多
Introduction: Controlling hypertension across world continues to be challenging. Managing hypertension is not only concerned with lowering blood pressure by using antihypertensive medications;it also aims to minimize ...Introduction: Controlling hypertension across world continues to be challenging. Managing hypertension is not only concerned with lowering blood pressure by using antihypertensive medications;it also aims to minimize its consequences through adopting self-care practices. Compliance with self-care practices among patients with hypertension is considered a multidimensional phenomenon. The phenomenon of hypertension has been studied quantitatively, however;little qualitative studies were conducted to understand the compliance with self-care among patients with hypertension. Aim: To understand the process that patients with hypertension go through to comply with self-care practices. Methods: This study used a qualitative design that followed constructivist grounded theory approach;purposive sampling was used to recruit participants from cardiac clinics;semi structured, in-depth and face-to-face interview was used as a major method for data collection. Findings: Four participants with hypertension participated in this study;the phenomena of self-care was identified as the central phenomena;the start of the disease was identified as a casual condition;beliefs toward hypertension disease, beliefs toward self-care practices, knowledge and awareness regarding hypertension disease and self-care practices were identified as strategies;experiencing self-care practices was identified as consequence and being patients with hypertension in a social context. Conclusions: The process of compliance with self-care has a path of actions and interactions. The process started from the moment of diagnosis where the patients start to think about self-care. The absence of health care context leads to varying level of compliance with self-care among patients with hypertension. This indicated the need for more effective patient and health care provider relationship, education and awareness campaign.展开更多
Following a new train of thinking, this paper has explored first the potential information in the ground resistivitydata observed by the existing geoelectric observation system, investigated and proposed a new dimensi...Following a new train of thinking, this paper has explored first the potential information in the ground resistivitydata observed by the existing geoelectric observation system, investigated and proposed a new dimensionlessgeoelectric precursor factor, the degree of ground resistivity anisotropy, S, and studied the characteristics of dynamic evolution pattern of S during the seismogenic process. The results show that, during the seismogenic process, the degree of ground resistivity anisotropy (S) displays h process of 'normal' → 'abnormal strengthening(amplitude, range)' → 'abnormal weakening'→ 'earthquake occurrence'→ 'normal'. The earthquake wouldoccur at the time when the S value has entered the late stage of strengthening and turns to weaken and in the gradient belt on the margin ofS anomaly region. The dynamic evolution pattern ofS reflects the changes of the tectonicstress field during the seismogenic process. Therefore, it would be possible to trace the process of earthquake generation and occurrence from the dynamic evolution pattern ofS so as to service eaJ'thquake prediction.展开更多
Joint inversion of teleseismic body-wave data and strong ground motion waveforms was applied to determine the rupture process of the 2010 Mentawai earthquake. To obtain stable solutions, smoothing and non-negative con...Joint inversion of teleseismic body-wave data and strong ground motion waveforms was applied to determine the rupture process of the 2010 Mentawai earthquake. To obtain stable solutions, smoothing and non-negative constraints were introduced. A total of 33 teleseismic stations and 5 strong ground motion stations supplied data. The teleseismic and strong ground motion data were separately windowed for 150 s and 250 s and bandpass filtered with frequencies of 0.001e1.0 Hz and 0.005e0.5 Hz, respectively. The finitefault model was established with length and width of 190 km and 70 km, and the initial seismic source parameters were set by referring to centroid moment tensor(CMT) solutions. Joint inversion results indicate that the focal mechanism of this earthquake is thrust fault type, and the strike, dip, and rake angles are generally in accordance with CMT results. The seismic moment was determined as 5.814 1020Nm(Mw7.8) and source duration was about 102 s, which is greater than those of other earthquakes of similar magnitude. The rupture nucleated near the hypocenter and then propagated along the strike direction to the northwest, with a maximum slip of 3.9 m. Large uncertainties regarding the amount of slip retrieved using different inversion methods still exist; however, the conclusion that the majority of slip occurred far from the islands at very shallow depths was found to be robust. The 2010 Mentawai earthquake was categorized as a tsunami earthquake because of the long rupture duration and the generation of a tsunami much larger than was expected for an earthquake of its magnitude.展开更多
基金National Natural Science Foundation of China (50378063) and Excellent Young Teachers Program of Ministry of Education.
文摘This paper proposes a method for simulation of non-stationary ground motion processes having the identical statistical feature, time-dependent power spectrum, with a given ground motion record, on the basis of review of simulation of non-stationary ground motion processes. The method has the following advantages: the sample processes are non-stationary both in amplitude and frequency, and both the amplitude and frequency non-stationarity depend on the target power spectrum; the power spectrum of any sample process does not necessarily accord with the target power spectrum, but statistically, it strictly accords with the target power spectrum. Finally, the method is verified by simulation of one acceleration record in Landers earthquake.
基金National Natural Science Foundation of China (50378063) and Excellent Young Teachers Program of Ministry of Education.
文摘This paper proposes a method for simulation of non-stationary ground motion processes having the identical statis-tical feature, time-dependent power spectrum, with a given ground motion record, on the basis of review of simu-lation of non-stationary ground motion processes. The method has the following advantages: the sample processes are non-stationary both in amplitude and frequency, and both the amplitude and frequency non-stationarity depend on the target power spectrum; the power spectrum of any sample process does not necessarily accord with the tar-get power spectrum, but statistically, it strictly accords with the target power spectrum. Finally, the method is veri-fied by simulation of one acceleration record in Landers earthquake.
文摘Introduction: Controlling hypertension across world continues to be challenging. Managing hypertension is not only concerned with lowering blood pressure by using antihypertensive medications;it also aims to minimize its consequences through adopting self-care practices. Compliance with self-care practices among patients with hypertension is considered a multidimensional phenomenon. The phenomenon of hypertension has been studied quantitatively, however;little qualitative studies were conducted to understand the compliance with self-care among patients with hypertension. Aim: To understand the process that patients with hypertension go through to comply with self-care practices. Methods: This study used a qualitative design that followed constructivist grounded theory approach;purposive sampling was used to recruit participants from cardiac clinics;semi structured, in-depth and face-to-face interview was used as a major method for data collection. Findings: Four participants with hypertension participated in this study;the phenomena of self-care was identified as the central phenomena;the start of the disease was identified as a casual condition;beliefs toward hypertension disease, beliefs toward self-care practices, knowledge and awareness regarding hypertension disease and self-care practices were identified as strategies;experiencing self-care practices was identified as consequence and being patients with hypertension in a social context. Conclusions: The process of compliance with self-care has a path of actions and interactions. The process started from the moment of diagnosis where the patients start to think about self-care. The absence of health care context leads to varying level of compliance with self-care among patients with hypertension. This indicated the need for more effective patient and health care provider relationship, education and awareness campaign.
文摘Following a new train of thinking, this paper has explored first the potential information in the ground resistivitydata observed by the existing geoelectric observation system, investigated and proposed a new dimensionlessgeoelectric precursor factor, the degree of ground resistivity anisotropy, S, and studied the characteristics of dynamic evolution pattern of S during the seismogenic process. The results show that, during the seismogenic process, the degree of ground resistivity anisotropy (S) displays h process of 'normal' → 'abnormal strengthening(amplitude, range)' → 'abnormal weakening'→ 'earthquake occurrence'→ 'normal'. The earthquake wouldoccur at the time when the S value has entered the late stage of strengthening and turns to weaken and in the gradient belt on the margin ofS anomaly region. The dynamic evolution pattern ofS reflects the changes of the tectonicstress field during the seismogenic process. Therefore, it would be possible to trace the process of earthquake generation and occurrence from the dynamic evolution pattern ofS so as to service eaJ'thquake prediction.
基金supported by National Natural Science Foundation of China (41304046)
文摘Joint inversion of teleseismic body-wave data and strong ground motion waveforms was applied to determine the rupture process of the 2010 Mentawai earthquake. To obtain stable solutions, smoothing and non-negative constraints were introduced. A total of 33 teleseismic stations and 5 strong ground motion stations supplied data. The teleseismic and strong ground motion data were separately windowed for 150 s and 250 s and bandpass filtered with frequencies of 0.001e1.0 Hz and 0.005e0.5 Hz, respectively. The finitefault model was established with length and width of 190 km and 70 km, and the initial seismic source parameters were set by referring to centroid moment tensor(CMT) solutions. Joint inversion results indicate that the focal mechanism of this earthquake is thrust fault type, and the strike, dip, and rake angles are generally in accordance with CMT results. The seismic moment was determined as 5.814 1020Nm(Mw7.8) and source duration was about 102 s, which is greater than those of other earthquakes of similar magnitude. The rupture nucleated near the hypocenter and then propagated along the strike direction to the northwest, with a maximum slip of 3.9 m. Large uncertainties regarding the amount of slip retrieved using different inversion methods still exist; however, the conclusion that the majority of slip occurred far from the islands at very shallow depths was found to be robust. The 2010 Mentawai earthquake was categorized as a tsunami earthquake because of the long rupture duration and the generation of a tsunami much larger than was expected for an earthquake of its magnitude.
