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Performance of the EDACS-ADP incorporating high-sensitivity troponin assay:Do components of major adverse cardiac events matter?
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作者 Yedalm Yoo Shin Ahn +1 位作者 Bora Chae Won Young Kim 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期175-180,共6页
BACKGROUND:The accelerated diagnostic protocol(ADP)using the Emergency Department Assessment of Chest pain Score(EDACS-ADP),a tool to identify patients at low risk of a major adverse cardiac event(MACE)among patients ... BACKGROUND:The accelerated diagnostic protocol(ADP)using the Emergency Department Assessment of Chest pain Score(EDACS-ADP),a tool to identify patients at low risk of a major adverse cardiac event(MACE)among patients presenting with chest pain to the emergency department,was developed using a contemporary troponin assay.This study was performed to validate and compare the performance of the EDACS-ADP incorporating high-sensitivity cardiac troponin I between patients who had a 30-day MACE with and without unstable angina(MACE I and II,respectively).METHODS:A single-center prospective observational study of adult patients presenting with chest pain suggestive of acute coronary syndrome was performed.The performance of EDACS-ADP in predicting MACE was assessed by calculating the sensitivity and negative predictive value.RESULTS:Of the 1,304 patients prospectively enrolled,399(30.6%;95%confidence interval[95%CI]:27.7%–33.8%)were considered low-risk using the EDACS-ADP.Among them,the rates of MACE I and II were 1.3%(5/399)and 1.0%(4/399),respectively.The EDACS-ADP showed sensitivities and negative predictive values of 98.8%(95%CI:97.2%–99.6%)and 98.7%(95%CI:97.0%–99.5%)for MACE I and 98.7%(95%CI:96.8%–99.7%)and 99.0%(95%CI:97.4%–99.6%)for MACE II,respectively.CONCLUSION:EDACS-ADP could help identify patients as safe for early discharge.However,when unstable angina was added to the outcome,the 30-day MACE rate among the designated lowrisk patients remained above the level acceptable for early discharge without further evaluation. 展开更多
关键词 Chest pain Major adverse cardiac event Acute coronary syndrome Emergency department
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Trend of extreme precipitation events over China in last 40 years 被引量:10
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作者 章大全 封国林 胡经国 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期736-742,共7页
Using the daily precipitation data of 740 stations in China from 1960 to 2000, the analysis on the variations and distributions of the frequency and the percentage of extreme precipitation to the annual rainfall have ... Using the daily precipitation data of 740 stations in China from 1960 to 2000, the analysis on the variations and distributions of the frequency and the percentage of extreme precipitation to the annual rainfall have been performed in this paper. Results indicate that the percentage of heavy rains (above 25mm/day) in the annual rainfall has increased, while on average the day number of heavy rains has slightly reduced during the past 40 years. In the end of 1970s and the beginning of 1980s, both the number of days with extreme precipitation and the percentage of extreme precipitation abruptly changed over China, especially in the northern China. By moving t test, the abrupt change year of extreme precipitation for each station and its spatial distribution over the whole country are also obtained. The abrupt change years concentrated in 1978-1982 for most regions of northern China while occurred at various stations in southern China in greatly different/diverse years. Besides the abrupt change years of extreme precipitation at part stations of Northwest China happened about 5 years later in comparison with that of the country's average. 展开更多
关键词 extreme precipitation events FREQUENCY abrupt change extreme events
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基于Matlab/SimEvents的截齿生产线仿真与分析
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作者 蒋南云 汪立海 +1 位作者 郑伟 孙玉玲 《煤矿机械》 北大核心 2014年第11期104-107,共4页
以截齿生产线拉式看板控制系统为研究对象,在建立的Petri网模型基础上,利用Matlab环境下的Sim Events仿真平台建立了仿真模型,并进行仿真实验得到不同系统参数设置下各生产线的平均生产率、缓冲区在制品数量及完成件数量,最后分析比较... 以截齿生产线拉式看板控制系统为研究对象,在建立的Petri网模型基础上,利用Matlab环境下的Sim Events仿真平台建立了仿真模型,并进行仿真实验得到不同系统参数设置下各生产线的平均生产率、缓冲区在制品数量及完成件数量,最后分析比较了系统参数与系统性能之间的关系,为提高采煤机截齿生产率、实现最优生产提供了依据。 展开更多
关键词 拉式生产 Matlab/Sim events 仿真
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How Behaviors and Certain Events Influence Legislative Language
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作者 杨正宇 《海外英语》 2013年第23期285-287,295,共4页
Legal language is a pretty formal language.As part of legal language,legislative language has all the basic features of legal language and legislative language has an accurate,plain,solemn,rigorous style.People interp... Legal language is a pretty formal language.As part of legal language,legislative language has all the basic features of legal language and legislative language has an accurate,plain,solemn,rigorous style.People interprete legislative language and act in accordance with laws.On the contrary,behaviors and certain events also influence the characteristics of legislative language,even trigger some conflicts with it.Confronted with some advantaged influence,legislators have to make some compromises or change the characteristics of legislative language.However,legislators should adhere to remain represantations of laws to resist disadvantaged impacts.As a result,it is need to research how behaviors and certain events influence legislative language. 展开更多
关键词 LEGISLATIVE LANGUAGE BEHAVIORS events INFLUENCE
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English Training for College Student Volunteers at Sports Events
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作者 刘伟 《海外英语》 2014年第13期76-77,共2页
This paper studies English training for student volunteers at large scale sports events with a comprehensive investigation of the undergraduate student volunteers from Capital University of Physical Education who have... This paper studies English training for student volunteers at large scale sports events with a comprehensive investigation of the undergraduate student volunteers from Capital University of Physical Education who have taken part in large scale sports events.By examining the current volunteer training situation,the author finds that there is a sever lack of professional and systematical English training for student volunteers at large scale sports events.The study shows focusing on sports events knowledge and requirements of the volunteers’specific job is crucial to the service level of the volunteers.The study concludes that the problem can be solved by developing new course books,innovating new flexible training methods,and offering more comprehensive training content.The recommended training methods include intensive group training,computer aided teaching,task training and on-the-spot training to make them fit their work soon. 展开更多
关键词 SPORTS events VOLUNTEERS ENGLISH TRAINING TRAINING
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Left atrial area index predicts adverse cardiovascular events in patients with unstable angina pectoris 被引量:6
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作者 Yi-Fan LI Wei-Hong LI +4 位作者 Zhao-Ping LI Xin-Heng FENG Wei-Xian XU Shao-Min CHEN Wei GAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第8期652-657,共6页
Background The left atrial size has been considered as a useful marker of adverse cardiovascular outcomes. However, it is not well known whether left atrial area index (LAAI) has predictive value for prognosis in pa... Background The left atrial size has been considered as a useful marker of adverse cardiovascular outcomes. However, it is not well known whether left atrial area index (LAAI) has predictive value for prognosis in patients with unstable angina pectoris (UAP). This study was aimed to assess the association between LAAI and outcomes in UAP patients. Methods We enrolled a total of 391 in-hospital patients diag- nosed as UAP. Clinical and echocardiographic data at baseline were collected. The patients were followed for the development of ad- verse cardiovascular (CV) events, including hospital readmission for angina pectoris, acute myocardial infarction (AMI), congestive heart failure (CHF), stroke and all-cause mortality. Results During a mean follow-up time of 26.3±8.6 months, 98 adverse CV events occurred (84 hospital readmission for angina pectoris, four AMI, four CHF, one stroke and five all-cause mortality). In a multivariate Cox model, LAAI [OR: 1.140, 95% CI: 1.01±1.279, P = 0.026], diastolic blood pressure (OR: 0.976, 95% CI: 0.956-0.996, P = 0.020) and pulse pressure (OR 1.020, 95% CI: 1.007-1.034, P = 0.004) were independent predictors for adverse CV events in UAP patients. Conclusions LAAI is a predictor of adverse CV events independent of clinical and other echocardiographic parameters in UAP patients. 展开更多
关键词 Adverse cardiovascular events Left atrial area index Prognostic factor Unstable angina pectoris
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Identification of anomalous fast bulk events in a p-type point-contact germanium detector 被引量:6
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作者 Ren-Ming-Jie Li Shu-Kui Liu +13 位作者 Shin-Ted Lin Li-Tao Yang Qian Yue Chang-Hao Fang Hai-Tao Jia Xi Jiang Qian-Yun Li Yu Liu Yu-Lu Yan Kang-Kang Zhao Lei Zhang Chang-Jian Tang Hao-Yang Xing Jing-Jun Zhu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第5期53-67,共15页
The ultralow detection threshold,ultralow intrinsic background,and excellent energy resolution of ptype point-contact germanium detectors are important for rare-event searches,in particular for the detection of direct... The ultralow detection threshold,ultralow intrinsic background,and excellent energy resolution of ptype point-contact germanium detectors are important for rare-event searches,in particular for the detection of direct dark matter interactions,coherent elastic neutrino-nucleus scattering,and neutrinoless double beta decay.Anomalous bulk events with an extremely fast rise time are observed in the CDEX-1B detector.We report a method of extracting fast bulk events from bulk events using a pulse shape simulation and reconstructed source experiment signature.Calibration data and the distribution of X-rays generated by intrinsic radioactivity verified that the fast bulk experienced a single hit near the passivation layer.The performance of this germanium detector indicates that it is capable of single-hit bulk spatial resolution and thus provides a background removal technique. 展开更多
关键词 p-type point-contact germanium detector Dark matter Pulse shape analysis Anomalous fast bulk events
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Electrocardiographic predictors of cardiovascular events in patients at high cardiovascular risk: a multicenter study 被引量:4
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作者 Rungroj Krittayaphong Muenpetch Muenkaew +3 位作者 Polakit Chiewvit Nithima Ratanasit Yodying Kaolawanich Arintaya Phrommintikul 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第8期630-638,共9页
Background There are limited data on the prevalence of electrocardiographic (ECG) abnormalities, and their value for predicting a major adverse cardiovascular event (MACE) in patients at high cardiovascular risk. This... Background There are limited data on the prevalence of electrocardiographic (ECG) abnormalities, and their value for predicting a major adverse cardiovascular event (MACE) in patients at high cardiovascular risk. This study aimed to determine the prevalence of ECG abnormalities in patients at high risk for cardiovascular events, and to identify ECG abnormalities that significantly predict MACE. Methods Patients aged ≥ 45 years with established atherosclerotic disease (EAD) were consecutively enrolled from the outpatient clinics of the six participating hospitals during April 2011 to March 2014. The following data were collected: demographic data, cardiovascular risk factors, history of cardiovascular event, physical examination, ECG and medications. ECG was analyzed using Minnesota Code criteria. MACE included cardiovascular death, non-fatal myocardial infarction, and hospitalization due to unstable angina or heart failure. Results A total of 2009 patients were included, 1048 patients (52.2%) had established EAD, and 961 patients (47.8%) had multiple risk factors (MRF). ECG abnormalities included atrial fibrillation (6.7%), premature ventricular contraction (5.4%), pathological Q-wave (Q/QS)(21.3%), T-wave inversion (20.0%), intraventricular ventricular conduction delay (IVCD)(7.3%), left ventricular hypertrophy (LVH)(12.2%), and AV block (12.5%). MACE occurred in 88 patients (4.4%). Independent predictors of MACE were chronic kidney disease, EAD, and the presence of atrial fibrillation, Q/QS, IVCD or LVH by ECG. Conclusions A high prevalence of ECG abnormalities was found. The prevalence of ECG abnormalities was high even among those with risk factors without documented cardiovascular disease. 展开更多
关键词 CARDIOVASCULAR events Electrocardiographic HIGH CARDIOVASCULAR RISK PREDICTORS
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Prediction of risk of cardiovascular events in patients with mild to moderate coronary artery lesions using naive Bayesian networks 被引量:2
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作者 Wei WANG Xian-Tao SONG +7 位作者 Yun-Dai CHEN Xing-Sheng YANG Feng XU Min ZHANG Kai TAN Fei YUAN Dong LI Shu-Zheng LYU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第11期899-905,共7页
Background This prospective study integrated multiple clinical indexes and inflammatory markers associated with coronary atherosclerotic vulnerable plaque to establish a risk prediction model that can evaluate a patie... Background This prospective study integrated multiple clinical indexes and inflammatory markers associated with coronary atherosclerotic vulnerable plaque to establish a risk prediction model that can evaluate a patient with certain risk factors for the likelihood of the occurrence of a coronary heart disease event within one year. Methods This study enrolled in 2686 patients with mild to moderate coronary artery lesions. Eighty-five indexes were recorded, included baseline clinical data, laboratory studies, and procedural characteristics. During the 1-year follow-up, 233 events occurred, five patients died, four patients suffered a nonfatal myocardial infarction, four patients underwent revascularization, and 220 patients were readmitted for angina pectoris. The Risk Estimation Model and the Simplified Model were conducted using Bayesian networks and compared with the Single Factor Models. Results The area under the curve was 0.88 for the Bayesian Model and 0.85 for the Simplified Model, while the Single Factor Model had a maximum area under the curve of 0.65. Conclusion The new models can be used to assess the short-term risk of individual coronary heart disease events and may assist in guiding preventive care. 展开更多
关键词 Bayesian networks Cardiovascular events PREDICTION
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C-reactive protein as a predictor for cardiac events in Chinese elderly patients with coronary heart disease 被引量:1
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作者 Guangyong HUANG Caiyi LU Xingli WU Yuxiao ZHANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2006年第2期78-81,共4页
Background and objective To assess the predictive value of C-reactive protein(CRP) for major adverse cardiac events and the association between CRP level and the coronary lesion morphology and extent in patients with ... Background and objective To assess the predictive value of C-reactive protein(CRP) for major adverse cardiac events and the association between CRP level and the coronary lesion morphology and extent in patients with coronary heart disease (CHD).Methods CRP was measured on admission in 177 consecutive elderly (age≥60 years) patients with CHD who underwent coronary angiography. Patients were divided into high CRP group (CRP≥3mg/L) and normal CRP group (CRP <3mg/L). The association between CRP levels and the coronary lesion features, including severity of stenosis (mild, moderate, severe), extent of lesion (diffused or nondiffused), eccentricity of the plaque (eccentric or non-eccentric) were analyzed. Patients were followed up for a mean of 8 months for the occurrences of major adverse cardiac events (MACE). Results Compared with patients in normal CRP group, patients in high CRP group were more frequently to have unstable angina, multi-vessel, diffuse, eccentric lesions, positive remodeling, and non-smooth plaques (P<0.01). Kaplan-Meier analysis showed patients in high CRP group had a significantly lower MACE-free survival rate than patients in normal CRP group (Log-rank = 12.0, P<0.01); Cox regression analysis indicated CRP level as an independent predictor for the occurrence of MACE (OR=3.16, P<0.05) Conclusions High CRP level is associated with more extend, severe and eccentric coronary lesions and is an independent predictor for MACE in elderly patients with CHD. 展开更多
关键词 C-reaction protein CORONARY ARTERY disease ANGIOGRAPHY major ADVERSE CARDIAC events
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Causation mechanism of coal miners' human errors in the perspective of life events 被引量:5
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作者 Zhang Weihua 《International Journal of Mining Science and Technology》 SCIE EI 2014年第4期581-586,共6页
In order to effectively decrease the safety accidents caused by coal miners’human errors,this paper probes into the causality between human errors and life events,coping,psychological stress,psychological function,ph... In order to effectively decrease the safety accidents caused by coal miners’human errors,this paper probes into the causality between human errors and life events,coping,psychological stress,psychological function,physiological function based on life events’vital influence on human errors,establishing causation mechanism model of coal miners’human errors in the perspective of life events by the researching method of structural equation.The research findings show that life events have significantly positive influence on human errors,with a influential effect value of 0.7945 and a influential effect path of‘‘life events—psychological stress—psychological function—physiological function—human errors’’and‘‘life events—psychological stress—physiological function—human errors’’. 展开更多
关键词 Life events Human errors Structural equation Coal miners
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Plasma big endothelin-1 is an effective predictor for ventricular arrythmias and end-stage events in primary prevention implantable cardioverter-defibrillator indication patients 被引量:1
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作者 Xiao-Yao LI Shuang ZHAO +6 位作者 Xiao-Han FAN Ke-Ping CHEN Wei HUA Zhi-Min LIU Xiao-Di XUE Bin ZHOU Shu ZHANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第7期427-433,共7页
Objective To investigate whether plasma big endothelin-1(ET-1) predicts ventricular arrythmias(VAs) and end-stage events in primary prevention implantable cardioverter-defibrillator(ICD) indication patigents. Methods ... Objective To investigate whether plasma big endothelin-1(ET-1) predicts ventricular arrythmias(VAs) and end-stage events in primary prevention implantable cardioverter-defibrillator(ICD) indication patigents. Methods In total, 207 patients fulfilling the inclusion criteria from Fuwai Hospital between January 2013 and December 2015 were retrospectively analyzed. The cohort was divided into three groups according to baseline plasma big ET-1 tertiles: tertile 1(< 0.38 pmol/L, n = 68), tertile 2(0.38–0.7 pmol/L, n = 69), and tertile 3(> 0.7 pmol/L, n = 70). The primary endpoints were VAs. The secondary endpoints were end-stage events comprising all-cause mortality and heart transplantation. Results During a mean follow-up period of 25.6 ± 13.9 months, 38(18.4%) VAs and 78(37.7%) end-stage events occurred. Big ET-1 was positively correlated with NYHA class(r = 0.165, P = 0.018), serum creatinine concentration(Scr;r = 0.147, P = 0.034), high-sensitivity C-reactive protein(hs-CRP;r = 0.217, P = 0.002), Lg NT-pro BNP(r = 0.463, P < 0.001), left ventricular end diastolic diameter(LVEDD;r = 0.234, P = 0.039) and negatively correlated with left ventricular ejection fraction(LVEF;r =-0.181, P = 0.032). Kaplan-Meier analysis showed that elevated big ET-1 was associated with increased risk of VAs and end-stage events(P < 0.05). In multivariate Cox regression models, big ET-1 was an independent risk factor for VAs(hazard ratio(HR) = 3.477, 95% confidence interval(CI): 1.352–8.940, P = 0.010, tertile 2 vs. tertile 1;HR = 4.112, 95% CI: 1.604–10.540, P = 0.003, tertile 3 vs. tertile 1) and end-stage events(HR = 2.804, 95% CI: 1.354–5.806, P = 0.005, tertile 2 vs. tertile 1;HR = 4.652, 95% CI: 2.288–9.459, P < 0.001, tertile 3 vs. tertile 1). Conclusions In primary prevention ICD indication patients, plasma big ET-1 levels can predict VAs and end-stage events and may facilitate ICD-implantation risk stratification. 展开更多
关键词 Big endothelin-1 End-stage events Implantable cardioverter-defibrillator implantation Primary prevention Ventricular arrythmias
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Intelligent identification and real-time warning method of diverse complex events in horizontal well fracturing 被引量:1
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作者 YUAN Bin ZHAO Mingze +2 位作者 MENG Siwei ZHANG Wei ZHENG He 《Petroleum Exploration and Development》 SCIE 2023年第6期1487-1496,共10页
The existing approaches for identifying events in horizontal well fracturing are difficult, time-consuming, inaccurate, and incapable of real-time warning. Through improvement of data analysis and deep learning algori... The existing approaches for identifying events in horizontal well fracturing are difficult, time-consuming, inaccurate, and incapable of real-time warning. Through improvement of data analysis and deep learning algorithm, together with the analysis on data and information of horizontal well fracturing in shale gas reservoirs, this paper presents a method for intelligent identification and real-time warning of diverse complex events in horizontal well fracturing. An identification model for "point" events in fracturing is established based on the Att-BiLSTM neural network, along with the broad learning system (BLS) and the BP neural network, and it realizes the intelligent identification of the start/end of fracturing, formation breakdown, instantaneous shut-in, and other events, with an accuracy of over 97%. An identification model for "phase" events in fracturing is established based on enhanced Unet++ network, and it realizes the intelligent identification of pump ball, pre-acid treatment, temporary plugging fracturing, sand plugging, and other events, with an error of less than 0.002. Moreover, a real-time prediction model for fracturing pressure is built based on the Att-BiLSTM neural network, and it realizes the real-time warning of diverse events in fracturing. The proposed method can provide an intelligent, efficient and accurate identification of events in fracturing to support the decision-making. 展开更多
关键词 horizontal well fracturing fracturing events intelligent identification real-time warning deep learning
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Responses of some landscape trees to the drought and high temperature events during 2006 and 2007 in Yamaguchi,Japan
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作者 王斐 山本晴彦 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A3期254-260,287,共8页
Extreme weather events were analyzed based on the meteorological data from the year of 1967 to 2007 for Yamaguchi, Japan. The responses from landscape trees were also investigated mainly by the analysis of image pixel... Extreme weather events were analyzed based on the meteorological data from the year of 1967 to 2007 for Yamaguchi, Japan. The responses from landscape trees were also investigated mainly by the analysis of image pixel and spectral reflectance. Results show that after the dry, hot and windy summer in 2007, many landscape trees in Yamaguchi City tended to respond the extreme weather events by reducing their leaf surface area and receiving less radiation energy. Premature leaf discoloration or defoliation appeared on some landscape tree species and leaf necrosis occurred on tip and margin of many Kousa dogwood (Cornus kousa) trees at unfavorable sites. Described by image pixel analysis method, the leaf necrotic area percentage (LNAP) of sampled dogwood trees averaged 41.6% and the sampled Sasanqua camellia (Camelia sasanqua) tree also showed fewer flowers in flower season of 2007 than that in 2006. By differential analysis of partial discolored crown, it presented a logistic differential equation of crown color for sweet gum (Liquidambar styraciflua) trees. It suggested that the persistent higher temperature and lower precipitation could be injurious to the sensitive landscape trees at poor sites, even in relative humid area like Yamaguchi. 展开更多
关键词 extreme meteorological event drought and high temperature landscape tree image pixel analysis response
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Net Events 2007凸显通信业三大热点
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作者 颜溢辉 《通信世界》 2007年第40期64-64,共1页
随着信息通信技术的不断发展,网络已经完全融入人们的生活中,并在逐渐影响且改变着人们的生活方式,网络已经成为人们工作和生活必需,支撑网络的力量也像人们的生活一样发生着日新月异的变化。在日前召开的Net Events 2007亚太媒体高峰... 随着信息通信技术的不断发展,网络已经完全融入人们的生活中,并在逐渐影响且改变着人们的生活方式,网络已经成为人们工作和生活必需,支撑网络的力量也像人们的生活一样发生着日新月异的变化。在日前召开的Net Events 2007亚太媒体高峰论坛上,NGN、运营商以太网和Triple-play再次成为探讨的热点。 展开更多
关键词 events 通信技术 TRIPLE 互操作性测试 网络设备 城域以太网论坛 媒体网关 网络体系结构
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An improved method for internal multiple elimination using the theory of virtual events
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作者 Pei-Nan Bao Ying Shi +2 位作者 Wei-Hong Wang Wei Zhang Zhe-Jun Pan 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2663-2674,共12页
Compared with first-order surface-related multiples from marine data,the onshore internal multiples are weaker and are always combined with a hazy and occasionally strong interference pattern.It is usually difficult t... Compared with first-order surface-related multiples from marine data,the onshore internal multiples are weaker and are always combined with a hazy and occasionally strong interference pattern.It is usually difficult to discriminate these events from complex targets and highly scattering overburdens,especially when the primary energy from deep layers is weaker than that from shallow layers.The internal multiple elimination is even more challenging due to the fact that the velocity and energy difference between primary reflections and internal multiples is tiny.In this study,we propose an improved method which formulates the elimination of the internal multiples as an optimization problem and develops a convolution factor T.The generated internal multiples at all interfaces are obtained using the convolution factor T through iterative inversion of the initial multiple model.The predicted internal multiples are removed from seismic data through subtraction.Finally,several synthetic experiments are conducted to validate the effectiveness of our approach.The results of our study indicate that compared with the traditional virtual events method,the improved method simplifies the multiple prediction process in which internal multiples generated from each interface are built through iterative inversion,thus reducing the calculation cost,improving the accuracy,and enhancing the adaptability of field data. 展开更多
关键词 Internal multiple Convolution factor ELIMINATION Virtual events
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Modeling of unsupervised knowledge graph of events based on mutual information among neighbor domains and sparse representation
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作者 Jing-Tao Sun Jing-Ming Li Qiu-Yu Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第12期2150-2159,共10页
Text event mining,as an indispensable method of text mining processing,has attracted the extensive attention of researchers.A modeling method for knowledge graph of events based on mutual information among neighbor do... Text event mining,as an indispensable method of text mining processing,has attracted the extensive attention of researchers.A modeling method for knowledge graph of events based on mutual information among neighbor domains and sparse representation is proposed in this paper,i.e.UKGE-MS.Specifically,UKGE-MS can improve the existing text mining technology's ability of understanding and discovering high-dimensional unmarked information,and solves the problems of traditional unsupervised feature selection methods,which only focus on selecting features from a global perspective and ignoring the impact of local connection of samples.Firstly,considering the influence of local information of samples in feature correlation evaluation,a feature clustering algorithm based on average neighborhood mutual information is proposed,and the feature clusters with certain event correlation are obtained;Secondly,an unsupervised feature selection method based on the high-order correlation of multi-dimensional statistical data is designed by combining the dimension reduction advantage of local linear embedding algorithm and the feature selection ability of sparse representation,so as to enhance the generalization ability of the selected feature items.Finally,the events knowledge graph is constructed by means of sparse representation and l1 norm.Extensive experiments are carried out on five real datasets and synthetic datasets,and the UKGE-MS are compared with five corresponding algorithms.The experimental results show that UKGE-MS is better than the traditional method in event clustering and feature selection,and has some advantages over other methods in text event recognition and discovery. 展开更多
关键词 Text event mining Knowledge graph of events Mutual information among neighbor domains Sparse representation
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Video events recognition by improved stochastic parsing based on extended stochastic context-free grammar representation
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作者 曹茂永 赵猛 +1 位作者 裴明涛 赵增顺 《Journal of Beijing Institute of Technology》 EI CAS 2013年第1期81-88,共8页
Video events recognition is a challenging task for high-level understanding of video se- quence. At present, there are two major limitations in existing methods for events recognition. One is that no algorithms are av... Video events recognition is a challenging task for high-level understanding of video se- quence. At present, there are two major limitations in existing methods for events recognition. One is that no algorithms are available to recognize events which happen alternately. The other is that the temporal relationship between atomic actions is not fully utilized. Aiming at these problems, an algo- rithm based on an extended stochastic context-free grammar (SCFG) representation is proposed for events recognition. Events are modeled by a series of atomic actions and represented by an extended SCFG. The extended SCFG can express the hierarchical structure of the events and the temporal re- lationship between the atomic actions. In comparison with previous work, the main contributions of this paper are as follows: ① Events (include alternating events) can be recognized by an improved stochastic parsing and shortest path finding algorithm. ② The algorithm can disambiguate the detec- tion results of atomic actions by event context. Experimental results show that the proposed algo- rithm can recognize events accurately and most atomic action detection errors can be corrected sim- ultaneously. 展开更多
关键词 video events recognition stochastic context-flee grammar stochastic parsing tempo-ral relationship
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Automatic microseismic events detection using morphological multiscale top-hat transformation
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作者 Guo-Jun Shang Wei-Lin Huang +3 位作者 Li-Kun Yuan Jin-Song Shen Fei Gao Li-Song Zhao 《Petroleum Science》 SCIE CAS CSCD 2022年第5期2027-2045,共19页
The occurrence of microseismic is not random but is related to the physical properties of the underground medium.Due to the low intensity and the influence of noise,microseismic eventually lead to poor signal-to-noise... The occurrence of microseismic is not random but is related to the physical properties of the underground medium.Due to the low intensity and the influence of noise,microseismic eventually lead to poor signal-to-noise ratio.We proposed a method for automatic detection of microseismic events by adoption of multiscale top-hat transformation.The method is based on the difference between the signal and noise in the multiscale top-hat transform section and achieves the detection on a specific section.The microseismic data are decomposed into different scales by multiscale morphology top-hat transformation firstly.Then the potential microseismic events could be detected by picking up the peak value in the multiscale top-hat section,and the characteristic profile obtains the start point with a specific threshold value.Finally,the synthetic data experiences demonstrate the advantages of this method under strong and weak noisy conditions,and the filed data example also shows its reliability and adaptability. 展开更多
关键词 Microseismic events detection Multiscale morphology Top-hat transformation
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Video Events Recognition by Scene and Group Context
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作者 裴明涛 王亚菲 赵猛 《China Communications》 SCIE CSCD 2013年第11期165-171,共7页
The ability to recognise video events has become increasingly more popular owing to its extensive practical applications.Most events will occur in certain scene with certain people,and the scene context and group cont... The ability to recognise video events has become increasingly more popular owing to its extensive practical applications.Most events will occur in certain scene with certain people,and the scene context and group context provide important information for event recognition.In this paper,we present an algorithm to recognise video events in different scenes in which there are multiple agents.First,we recognise events for each agent based on Stochastic Context Sensitive Grammar(SCSG).Then we propose the model of a scene in order to infer the scene in which the events occur,and we use a co-occurrence matrix of events to represent the group context.Finally,the scene and group context are exploited to distinguish events having similar structures.Experimental results show that by adding the scene and group context,the performance of events recognition can be significantly improved. 展开更多
关键词 events recognition scene context group context
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