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蜂窝夹层结构脱粘缺陷电磁锤敲击检测模型及持力时间分析 被引量:4
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作者 肖轲迪 张颖 +2 位作者 吴君豪 罗明 吴时红 《宇航材料工艺》 CAS CSCD 北大核心 2020年第5期70-75,共6页
为了定量描述蜂窝夹层结构敲击检测中敲击头持力时间与脱粘缺陷直径和面板特性的依赖关系,建立了敲击过程的力学模型,推导和分析了持力时间随缺陷直径和面板拉力的变化情况,并与试验数据做了拟合和比较。结果表明,在拟合的面板拉力取值... 为了定量描述蜂窝夹层结构敲击检测中敲击头持力时间与脱粘缺陷直径和面板特性的依赖关系,建立了敲击过程的力学模型,推导和分析了持力时间随缺陷直径和面板拉力的变化情况,并与试验数据做了拟合和比较。结果表明,在拟合的面板拉力取值下,模型计算值与试验值吻合较好。模型可用来计算持力时间的数值和分析持力时间的变化趋势。对于同一面板的脱粘缺陷,持力时间随缺陷直径的增大而增大。对于同种材料面板的相同直径的脱粘缺陷,持力时间随面板厚度的增大而减小。对于同厚度面板的相同直径的脱粘缺陷,复合材料碳环氧树脂面板对应的持力时间短于铝面板。 展开更多
关键词 蜂窝夹层结构 敲击检测 持力时间
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Investigation of the effect of military stress on the prevalence of functional bowel disorders 被引量:4
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作者 Xian-Zhao Yu Hai-Feng Liu Zhen-Xue Sun 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第23期3004-3007,共4页
AIM: To investigate the morbidity of functional bowel disorders (FBD) under military stress conditions in order to lay foundations for the prevention and treatment of this disease. METHODS: Four hundred and fifty-seve... AIM: To investigate the morbidity of functional bowel disorders (FBD) under military stress conditions in order to lay foundations for the prevention and treatment of this disease. METHODS: Four hundred and fifty-seven soldiers who were assigned to specified services and 471 soldiers who were assigned to routine services were enrolled using cluster sampling, with the latter as a control group. They were surveyed using the Rome Ⅲ FBD standard questionnaire. The FBD symptom question-naire included FBD-related symptoms, severity, dura- tion or attack time, and accompanying symptoms. RESULTS: The morbidity of the military stress group (14.6%) was significantly higher than in the control group (9.98%) ( 2 = 4.585, P < 0.05). The incidence of smoking, abdominal pain and acid regurgitation ( 2 = 4.761, P < 0.05) as well as the ZUNG anxiety/depression scores ( 2 = 7.982, P < 0.01) were also sig- nificantly higher in the military stress group compared with the control group. ZUNG anxiety ( 2 = 11.523, P < 0.01) and depression ( 2 = 5.149, P < 0.05) scores were higher in the FBD group compared with the non-FBD group. The differences in the ZUNG self-rated anxiety and depression scales between the 2 groups were statistically significant ( 2 = 14.482, P < 0.01 and 2 = 6.176, P < 0.05). CONCLUSION: The morbidity of FBD was higher under military stress conditions. 展开更多
关键词 Military stress Functional bowel disorders SOLDIER Self-rating anxiety Depression scale
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Left univentricular pacing for cardiac resynchronization therapy using rate-adaptive atrioventricular delay 被引量:4
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作者 Li-Jin PU Yu WANG +9 位作者 Lu-Lu ZHAO Tao GUO Shu-Min LI Bao-Tong HUA Ping YANG Jun YANG Yan-Zhou LU Liu-Qing YANG Ling ZHAO Hai-Yun LUO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第2期118-126,共9页
Objective To evaluate left univentricular (LUV) pacing for cardiac resynchronization therapy (CRT) using a rate-adaptive atrioven- tricular delay (RAAVD) algorithm to track physiological atrioventricular delay ... Objective To evaluate left univentricular (LUV) pacing for cardiac resynchronization therapy (CRT) using a rate-adaptive atrioven- tricular delay (RAAVD) algorithm to track physiological atrioventricular delay (AVD). Methods A total of 72 patients with congestive heart failure (CHF) were randomized to RAAVD LUV pacing versus standard biventricular (BiV) pacing in a 1 : 1 ratio. Echocardiography was used to optimize AVD for both groups. The effects of sequential BiV pacing and LUV pacing with optimized A-V (right atrio-LV) delay using an RAAVD algorithm were compared. The standard deviation (SD) of the S/R ratio in lead VI at five heart rate (HR) segments (Rs/R-SD5), defined as the "tracking index," was used to evaluate the accuracy of the RAAVD algorithm for tracking physiological AVD. Results TheQRS complex duration (132 ± 9.8 vs. 138± 10ms, P 〈 0.05), the time required for optimization (21 ±5 vs. 50±8min, P〈 0.001), the mitral regurgitant area (1.9 ± 1.1 vs. 2.5 ± 1.3 em2, P 〈 0.05), the interventricular mechanical delay time (60.7 ± 13.3 ms vs. 68.3 ± 14.2 ms, P 〈 0.05), and the average annual cost (13,200 ± 1000 vs. 21,600 ± 2000 RMB, P 〈 0.001) in the RAAVD LUV pacing group were significantly less than those in the standard BiV pacing group. The aortic valve velocity-time integral in the RAAVD LUV pacing group was greater than that in the standard BiV pacing group (22.7 ± 2.2 vs. 21.4 ± 2.1 cm, P 〈 0.05). The Rs/R-SD5 was 4.08 ± 1.91 in the RAAVD LUV pacing group, and was significantly negatively correlated with improved left ventricular ejection fraction (LVEF) (ALVEF, Pearson's r = -0.427, P = 0.009), and positively correlated with New York Heart Association class (Spearman's r - 0.348, P 0.037). Conclusions RAAVD LUV pacing is as effective as standard BiV pacing, can be more physiological than standard BiV pacing, and can de- crease the average annual cost of CRT. 展开更多
关键词 Cardiac resynchronization therapy Congestive heart failure Left univentricular pacing Rate adaptive atrio-ventricular delay
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Spatial and Temporal Variability of Thermal Stress to China's Coral Reefs in South China Sea 被引量:7
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作者 ZUO Xiuling SU Fenzhen +2 位作者 WU Wenzhou CHEN Zhike SHI Wei 《Chinese Geographical Science》 SCIE CSCD 2015年第2期159-173,共15页
Coral bleaching, caused by elevated sea surface temperature(SST), is occurring more frequently and seriously worldwide. Due to the lack of field observations, we understand little about the large-scale variability of ... Coral bleaching, caused by elevated sea surface temperature(SST), is occurring more frequently and seriously worldwide. Due to the lack of field observations, we understand little about the large-scale variability of thermal stress in the South China Sea(SCS) and its effect on China's coral reefs. This paper used 4-km high resolution gap-filled SST(Filled SST) data and thermal stress data related to coral bleaching derived from Coral Reef Temperature Anomaly Database(Co RTAD) to quantify the spatial and temporal characteristics of chronic thermal stress and acute thermal stress to China's coral reefs in SCS from 1982 to 2009. We analyzed the trend of SST in summer and the thermal stress frequency, intensity and duration during this period. The results indicate that, as a chronic thermal stress, summer mean SST in SCS shows an average upward trend of 0.2℃/decade and the spatial pattern is heterogeneous. Waters of Xisha Islands and Dongsha Islands of the northern SCS are warming faster through time compared to Zhongsha Islands and Nansha Islands sea areas of the southern SCS. High frequency bleaching related thermal stress events for these reefs are seen in the area to the northwest of Luzon Island. Severe anomaly thermal stress events are more likely to occur during the subsequent year of the El Nino year for these coral reefs. Besides, the duration of thermal stress varies considerably by anomaly year and by region. 展开更多
关键词 coral reef sea surface temperature(SST) thermal stress El Nino-Southern Oscillation(ENSO) South China Sea(SCS)
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Evolution of gastroenterology training 被引量:2
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作者 Hanna Telleman Trevlyn Felicity Burger Chris Jacob Johan Mulder 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第15期1793-1798,共6页
There have been rapid developments in gastroenterology(GE)over the last decade.Up until the late 1980s,GE-training was incorporated in Internal Medicine training.The introduction of endoscopy has necessitated the need... There have been rapid developments in gastroenterology(GE)over the last decade.Up until the late 1980s,GE-training was incorporated in Internal Medicine training.The introduction of endoscopy has necessitated the need for additional training.Around the world different national boards have developed their own curricula which will be discussed in this paper. Emphasis will be placed on the curriculum recently introduced in The Netherlands.The internal medicine component has become a two-year requirement (Common Trunk)and the duration of training in GE has been extended to four years.Because of the growing complexity of GE,there are now four subspecialties:Interventional Endoscopy,Neuromotility, Oncology and Hepatology that trainees can choose from.These subspecialties each have predefined specific requirements.The World Gastroenterology Organization has drawn up a standard curriculum which can be of help to the boards in different countries. The curriculum emphasizes the knowledge and skill components.The curriculum also defines the training recommendations,the requirements of training facilities and competence evaluation of fellows and facilities,while less is said about research,finance and the number of gastroenterologists required.In the coming decades the curriculum will need to be revised continuously.Personalization of the curriculum will be the next challenge for the years to come. 展开更多
关键词 CAREER Common Trunk Curriculum Endoscopy Fellow FELLOWSHIP GASTROENTEROLOGY HEPATOLOGY Program TRAINING
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New developments in immunotherapy for lymphoma 被引量:6
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作者 Benjamin Heyman Yiping Yang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2018年第3期189-209,共21页
The development of immunotherapies for lymphoma has undergone a revolutionary evolution over the past decades. Since the advent of rituximab as the first successful immunotherapy for B-cell non-Hodgkin lymphoma over t... The development of immunotherapies for lymphoma has undergone a revolutionary evolution over the past decades. Since the advent of rituximab as the first successful immunotherapy for B-cell non-Hodgkin lymphoma over two decades ago, a plethora of new immunotherapeutic approaches to treat lymphoma has ensued. Four of the most exciting classes of immunotherapies include:chimeric antigen receptor T-cells, bispecific antibodies, immune checkpoint inhibitors, and vaccines. However, with addition of these novel therapies the appropriate timing of treatment, optimal patient population, duration of therapy, toxicity, and cost must be considered. In this review, we describe the most-promising immunotherapeutic approaches for the treatment of lymphoma in clinical development, specifically focusing on clinical trials performed to date and strategies for improvement. 展开更多
关键词 CAR-T cells immune checkpoint blockade bispecific antibodies
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Treatment of Domestic Sewage by Two-Stage-Bio-Contact Oxidation Process
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作者 LIXiang-dong FENGQi-yan LIUZhong-wei XIAOXin LINGuo-hua 《Journal of China University of Mining and Technology》 EI 2005年第1期60-63,共4页
Effects of hydraulic retention time (HRT ) and gas volume on efficiency of wastewater treatment are dis- cussed based on a simulation experiment in which the domestic swage was treated by the two-stage-bio-contact oxi... Effects of hydraulic retention time (HRT ) and gas volume on efficiency of wastewater treatment are dis- cussed based on a simulation experiment in which the domestic swage was treated by the two-stage-bio-contact oxida- tion process. The result shows that the average CODCr, BOD5 , suspended solid (SS), and ammonia-nitrogen removal rate are 94.5 %, 93.2 %, 91.7 % and 46.9 %, respectively, under the conditions of a total air/water ratio of 5∶1 , an air/water ratio of 3:1 for oxidation tank 1 and 2:1for oxidation tank 2and a hydraulic retention time of 1 h for each stage. This method is suitable for domestic sewage treatment of residential community and small towns as well. 展开更多
关键词 two-stage-bio-contact oxidation process domestic swage hydraulic retention time (HRT) air/water ratio
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Production and characterization of biosurfactant from Bacillus subtilis CCTCC AB93108 被引量:1
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作者 刘智峰 曾光明 +2 位作者 钟华 傅海燕 刘小兰 《Journal of Central South University》 SCIE EI CAS 2010年第3期516-521,共6页
The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented w... The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4-100 ℃) and a long period of duration. 展开更多
关键词 Bacillus subtilis BIOSURFACTANT SURFACTANT emulsification activity emulsion stability HYDROPHOBICITY
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Effect of Dietary Vitamin E on the Sperm Quality of Turbot(Scophthalmus maximus) 被引量:2
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作者 XU Houguo HUANG Lina +2 位作者 LIANG Mengqing ZHENG Keke WANG Xinxing 《Journal of Ocean University of China》 SCIE CAS 2015年第4期695-702,共8页
A 3-month feeding experiment was conducted in an in-door seawater system to investigate the effect of dietary vitamin E (Ve) on the sperm quality of turbot (Scophthalmus maximus). D-α-tocopherol acetate was suppl... A 3-month feeding experiment was conducted in an in-door seawater system to investigate the effect of dietary vitamin E (Ve) on the sperm quality of turbot (Scophthalmus maximus). D-α-tocopherol acetate was supplemented to the basal (control) diet (65.14 mg kg-l Ve) to obtain low and high levels of dietary Ve (244.60 mgkg-1, LVe; 721.60 mg kg-1, HVe). Compared with the con- trol, sperm concentration was significantly increased in Ve-supplemented groups (LVe and HVe); while relative sperm volume and testis-somatic index were significantly increased in group HVe only. Sperm motility duration was significantly longer in group HVe than in the control, but no significant difference was observed in percent motility among groups. Sperm size, the uniformity of mito- chondrial size, and the integrity of mitochondria cristae and plasma membrane were improved by dietary Ve, especially in HVe. The content of Ve in testis and liver as well as polyunsaturated fatty acids in sperm increased with dietary Ve. These results suggested that dietary Ve, especially at the high level (721.60 mg kgl), significantly improved sperm concentration and motility duration and main- tained normal sperm morphology of turbot.Abstract A 3-month feeding experiment was conducted in an in-door seawater system to investigate the effect of dietary vitamin E (Ve) on the sperm quality of turbot (Scophthalmus maximus). D-α-tocopherol acetate was supplemented to the basal (control) diet (65.14 mg kg-l Ve) to obtain low and high levels of dietary Ve (244.60 mgkg-1, LVe; 721.60 mg kg-1, HVe). Compared with the con- trol, sperm concentration was significantly increased in Ve-supplemented groups (LVe and HVe); while relative sperm volume and testis-somatic index were significantly increased in group HVe only. Sperm motility duration was significantly longer in group HVe than in the control, but no significant difference was observed in percent motility among groups. Sperm size, the uniformity of mito- chondrial size, and the integrity of mitochondria cristae and plasma membrane were improved by dietary Ve, especially in HVe. The content of Ve in testis and liver as well as polyunsaturated fatty acids in sperm increased with dietary Ve. These results suggested that dietary Ve, especially at the high level (721.60 mg kgl), significantly improved sperm concentration and motility duration and main- tained normal sperm morphology of turbot. 展开更多
关键词 male turbot vitamin E dietary supplementation sperm quality
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Determining the degree of saturation of rocks as a function of time:A case study from mountainous area of Turkey
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作者 Serhat DAG 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2307-2319,共13页
The aim of this study is to scrutinize whether, in terms of saturation, the 48 hour duration suggested by ISRM(International Society for Rock Mechanics) methods and ASTM(American Society for Testing and Materials) sta... The aim of this study is to scrutinize whether, in terms of saturation, the 48 hour duration suggested by ISRM(International Society for Rock Mechanics) methods and ASTM(American Society for Testing and Materials) standard in rocks is sufficient or not, and to examine how the degree of saturation of rocks may be determined as a function of time. For this purpose, samples from five different rock groups including igneous(andesite, granite, andesitic tuff) and sedimentary(limestone, sandstone) exposed in Gümü?hane city which is from mountainous area of north-eastern Turkey, have been compiled. Measurements were taken on the samples left for saturation under laboratory conditions as a result of which the degree of saturation values at the end of these time periods were determined. Similarly, at the end of 48 hours, the samples were left to dry under atmospheric conditions in the laboratory environment and their time dependent degree of saturation were also calculated at different times. The changes as a function of time in the degree of saturation were then examined mathematically using non-linear, exponential and logarithmic functions. Graphs and equations related with the acquired time-degree of saturation values and the correlation coefficient(r) values for these equalities have indicated a high accordance between time and degree of saturation for the studied rock groups. The applied methodology will be beneficial for determining the degree of saturation based on time for engineering studies that will be carried out in similar lithologies. 展开更多
关键词 Degree of saturation POROSITY TIME Correlation coefficient
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INFLUENCE OF DIFFERENT NEEDLE-RETAINING DURATION ON CEREBRAL HEMODYNAMICS OF CEREBRAL PARALYSIS CHILDREN 被引量:1
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作者 袁青 王琴玉 +3 位作者 冯健强 张壮涛 陈雪云 靳瑞 《World Journal of Acupuncture-Moxibustion》 2004年第2期7-10,共4页
Objective: To investigate the effects of different needle-retaining duration on cerebral hemodynamics in cerebral paralysis (CP) children. Methods: A total of 20 cases of CP children were subjected into this study. Ch... Objective: To investigate the effects of different needle-retaining duration on cerebral hemodynamics in cerebral paralysis (CP) children. Methods: A total of 20 cases of CP children were subjected into this study. Changes of systolic peak value (Vs), blood flow velocity at the end-diastolic phase (Ved), mean velocity (Vm), pulsation index (PI) and resistance index (RI) of the cerebral hemodynamics before and after performing JIN’s Three-Needling Therapy with the needles retained for 30 min (group A) and 5 min (group B) were observed by using transcranial Doppler ultrasonography (TCD). Results: After acupuncture, the blood flow in the middle cerebral artery (MCA), anterior cerebral artery (ACA) and posterior cerebral artery (PCA) was accelerated, and the resistance of blood vessels decreased. The effect of needle-retaining-30 min was better than that of needle-retaining-5 min. Conclusion: In treating cerebral paralysis by using JIN’s Three-Needling Therapy, sufficient stimulation provided by needle remaining is an important factor for achieving satisfactory therapeutic effects. 展开更多
关键词 JIN's Three-Needling Therapy Cerebral paralysis Time-effect relation Transcranial Doppler ultrasonography (TCD)
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Improvement of chromium biosorption through protoplast electrofusion between Candida tropicalis and Candida lipolytica 被引量:3
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作者 何宝燕 尹华 +4 位作者 杨峰 叶锦韶 彭辉 卢显妍 张娜 《Journal of Central South University》 SCIE EI CAS 2012年第6期1693-1701,共9页
Protoplasts from Candida tropicalis and Candida lipolytica were fused under an optimized electrofusion (electrical pulse strength 6 kV/cm, pulse duration time 40μs and pulse times 5) and then regenerated on YEPD me... Protoplasts from Candida tropicalis and Candida lipolytica were fused under an optimized electrofusion (electrical pulse strength 6 kV/cm, pulse duration time 40μs and pulse times 5) and then regenerated on YEPD media for achieving new genotypes with higher chromium loading capacity. A target fusant RHJ-004 was screened out by its chromium resistance and chromium-sorbing capacity tests for further research. The comparative study of applicability shows that the fusant has better performance than its parent strains in respect of solution pH, biomass concentration and chromium loading capacity. Especially for treating low concentration Cr(VI) (〈20 mg/L), above 80% chromium is sequestered from the aqueous phase at pH 1-9. Atomic force microscopy (AFM) visualizes the distribution of chromium on the binding sites of the cells, suggesting that the altered surface structure and intracellular constitutes of the fusant associate with its increased biosorption capacity. The rapid biosorption processes of chromium foUow the Langmuir model well. 展开更多
关键词 CHROMIUM BIOSORPTION FUSANT PROTOPLAST ELECTROFUSION
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On the Redistribution of Bending Moments in Two-Span RC Beams and Slabs Exposed to Fire
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作者 Robert Kowalski Marek Urbafiski 《Journal of Civil Engineering and Architecture》 2013年第2期158-173,共16页
This paper shows consideration of decrease in cross-section stiffness in commonly used in practice RC (reinforced concrete) beams and slabs in cases when only reinforcing bars or only concrete compressed zone, which... This paper shows consideration of decrease in cross-section stiffness in commonly used in practice RC (reinforced concrete) beams and slabs in cases when only reinforcing bars or only concrete compressed zone, which is subjected to fire. Analyses were based on: (1) standard fire curve [EN 1991-1-2]; (2) 500℃isotherm method assumptions [EN 1992-1-2]; (3) mechanical properties of reinforcing steel heated up to high temperature. Afterwards, based on estimated decrease of cross-sections stiffness, the redistribution of bending moments was calculated in some cases of two-span RC beams and slabs subjected to fire from their bottom face. Due to the bending moment redistribution, one could expect a reduction of bending moments in span cross-sections and an increase of support bending moment. As a result of this phenomenon, the ultimate limit state of the structural multi span elements might occur after shorter fire duration than it could be expected when redistribution of bending moments is neglected. 展开更多
关键词 Concrete CROSS-SECTION fire design stiffness.
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Research on Frequency of the Aftershock Sequence of the Wenchuan Earthquake Based on Coseismic Coulomb Stress Change
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作者 Jia Ruo Jiang Haikun 《Earthquake Research in China》 CSCD 2015年第1期84-102,共19页
By the aftershock frequency estimation method based on the calculation of coseismic static Coulomb stress changes and rate-and state-dependent fault constitutive law,we calculate the frequency of "direct "af... By the aftershock frequency estimation method based on the calculation of coseismic static Coulomb stress changes and rate-and state-dependent fault constitutive law,we calculate the frequency of "direct "aftershocks of the Wenchuan earthquake related to coseismic static Coulomb stress changes in its aftershock zone and the areas nearby.It shows that the frequency is significantly lower than the truth in the main rupture zone,especially in the southern rupture zone,due to the decrease of stress level on the rupture plane of the main shock resulting from coseismic Coulomb stress change.The study also shows that the effect of the Coulomb stress change on the duration of aftershock activity is associated with the lower limit magnitude.The duration is about 15-16 months for aftershocks above ML4.0,and close to 60 months for aftershocks above ML3.5.In this period,the ratio of the"direct"aftershocks caused by coseismic Coulomb stress change ranges between 44.7% to48.6%,which suggests that,even in the "effective"period of coseismic Coulomb stress changes,about half of the aftershocks on the main shock rupture plane are independent of coseismic Coulomb stress changes.It is pointed out that those aftershocks may be related to the afterslip or the viscoelastic relaxation,which are time dependent cases. 展开更多
关键词 Wenchuan earthquake Static Coulomb failure stress change "Direct"aftershock frequency Aftershock spatial distribution Afterslip
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The Co-seismic Response of Underground Fluid in Yunnan to the Nepal MS8.1 Earthquake
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作者 Zhang Li Su Youjin +2 位作者 Luo Ruijie Gao Wenfei Zhang Ping 《Earthquake Research in China》 CSCD 2017年第2期201-212,共12页
In this paper,statistics are taken on the co-seismic response of underground fluid in Yunnan to the Nepal M_S8. 1 earthquake,and the co-seismic response characteristics of the water level and water temperature are ana... In this paper,statistics are taken on the co-seismic response of underground fluid in Yunnan to the Nepal M_S8. 1 earthquake,and the co-seismic response characteristics of the water level and water temperature are analyzed and summarized with the digital data. The results show that the Nepal M_S8. 1 earthquake had greater impact on the Yunnan region,and the macro and micro dynamics of fluids showed significant co-seismic response. The earthquake recording capacity of water level and temperature measurement is significantly higher than that of water radon and water quality to this large earthquake; the maximum amplitude and duration of co-seismic response of water level and water temperature vary greatly in different wells. The changing forms are dominated by fluctuation and step rise in water level,and a rising or falling restoration in water temperature. From the records of the main shock and the maximum strong aftershock,we can see that the greater magnitude of earthquake,the higher ratio of the occurrence of co-seismic response,and in the same well,the larger the response amplitude,as well as the longer the duration. The amplitude and duration of co-seismic response recorded by different instruments in a same well are different. Water temperature co-seismic response almost occurred in wells with water level response,indicating that the well water level and water temperature are closely related in co-seismic response,and the well water temperature seismic response was caused mainly by well water level seismic response. 展开更多
关键词 Nepal Ms8. 1 earthquake Underground fluid in Yunnan Co-seismic response Well water level Water temperature Digital observations Step change Fluctuation
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Formation of RF Plasma Transport Channel in External B-Field
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作者 Ping Feng Vitaly Bystritskii +2 位作者 Ivan Isakov Vasily Matvienko Kurt Walters 《Journal of Energy and Power Engineering》 2012年第5期725-729,共5页
The paper describes experiments on formation of a plasma channel with imbedded B-field for transporting high power ion beam. The plasma was generated with a 5-turn loop inductive antenna driven by an H-bridge type RF ... The paper describes experiments on formation of a plasma channel with imbedded B-field for transporting high power ion beam. The plasma was generated with a 5-turn loop inductive antenna driven by an H-bridge type RF generator. The azimuthal B-field in the channel of 0.5-1.5 kG was formed by a pulsed current from external capacitor bank. Control of the hydrogen gas pressure was provided by an electromagnetic puffvalve. The paper describes experimental devices and results on the generated plasma parameters as function of RF frequency, antenna voltage, pulse duration and puffgas pressure. When operating at-1 kG B-field, ambient gas pressure in the range of few -10 mTorr, and 5 kV antenna voltage at resonant frequency of 150 kHz, the plasma density range was (3-7)×10^12 cm3 with a temperature of a few eV. 展开更多
关键词 PLASMA RF B-field ion beam high power ion beam.
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Effects of the duration of expressions on the recognition of microexpressions 被引量:15
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作者 Xun-bing SHEN Qi wu Xiao-lan FU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2012年第3期221-230,共10页
Objective: The purpose of this study was to investigate the effects of the duration of expressions on the recognition of microexpressions, which are closely related to deception. Methods: In two experiments, participa... Objective: The purpose of this study was to investigate the effects of the duration of expressions on the recognition of microexpressions, which are closely related to deception. Methods: In two experiments, participants were briefly (from 20 to 300 ms) shown one of six basic expressions and then were asked to identify the expression. Results: The results showed that the participants' performance in recognition of microexpressions increased with the duration of the expressions, reaching a turning point at 200 ms before levelling off. The results also indicated that practice could improve the participants' performance. Conclusions: The results of this study suggest that the proper upper limit of the duration of microexpressions might be around 1/5 of a second and confirmed that the ability to recognize microexpressions can be enhanced with practice. 展开更多
关键词 Duration of expressions Microexpressions Microexpression training tool (METT)
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Generating wind power time series based on its persistence and variation characteristics 被引量:4
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作者 LI Jing Hua LI Jia Ming +3 位作者 WEN Jin Yu CHENG Shi Jie XIE Hai Lian YUE Cheng Yan 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第12期2475-2486,共12页
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
关键词 wind power time series generation persistence characteristic variation characteristic markov chain monte carlomethod
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Characteristics of the double layer associated with terrestrial bow shock by THEMIS observation
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作者 LI ShiYou ZHANG ShiFeng +2 位作者 CAI Hong BAI XiBin XIE QiuHong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第4期562-572,共11页
This study presents observation and detailed analysis on the double layers (DLs) in the ramp and the foreshock contacting with the foot of the terrestrial bow shock by THEMIS on September 14, 2008 under enhanced dyn... This study presents observation and detailed analysis on the double layers (DLs) in the ramp and the foreshock contacting with the foot of the terrestrial bow shock by THEMIS on September 14, 2008 under enhanced dynamic pressure in the solar wind. The results reveal that: (1) The time duration of the double layers is nus 10-40 mV/m. (2) On assuming a propagation speed at the ion mainly 3-8 ms, and their max parallel electric field is miacoustic speed (vs), their spatial scale is estimated to be 0.3-1.15 km (about 75-200 2D). (3) The net potential drop of DLs is estimated to be 5-32 V. (4) The DLs in the ramp and the foreshock contacting to the foot of the bow shock is current-carrying as a result of development and evolution of nonlinear phase of instability in the self-consistent current-carrying plasma. The DLs may play an important role in strong turbulence in the foreshock contacting with the foot of the bow shock. 展开更多
关键词 bow shock double layer electron hole current-carrying plasma
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An investigation of the persistence property of wind power time series 被引量:5
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作者 SUN HaiShun LI JiaMing +4 位作者 LI JingHua Wu Tong WEN JinYu XIE HaiLian YUE ChengYan 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第8期1578-1587,共10页
Mining the inherent persistence property of the time series of wind power is crucial for forecasting and controlling wind power.Few common methods exist that can fully depict and quantify the persistence property.Base... Mining the inherent persistence property of the time series of wind power is crucial for forecasting and controlling wind power.Few common methods exist that can fully depict and quantify the persistence property.Based on the definition of the active power output state of a wind farm,this paper describes the statistical persistence property of the duration time and state transition.Based on the results of our analysis of significant amounts of wind power field measurements,it is found that the duration time of wind power conforms to an inverse Gaussian distribution.Additionally,the state transition matrix of wind power is discovered to yield a ridge property,the gradient of which is related to the time scale of interest.A systemaic methodology is proposed accordingly,allowing the statistical characteristics of the wind power series to be represented appropriately. 展开更多
关键词 characteristics analysis persistence property duration time state transition wind power series
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