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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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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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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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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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基于改进Event模型的通用航空器碰撞风险分析
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作者 黄晋 焦瑶瑶 +1 位作者 李云飞 刘厚荣 《火力与指挥控制》 CSCD 北大核心 2024年第10期191-196,共6页
随着通用航空的发展,空中交通流量将持续扩大,航空器碰撞风险增加。对Event模型进行改进,将拼接四棱锥碰撞盒代替原长方体碰撞盒,曲面间隔层代替平面间隔层,建立通用航空器碰撞风险模型。最后将塞斯纳172及运5B通用航空器作为实例对所... 随着通用航空的发展,空中交通流量将持续扩大,航空器碰撞风险增加。对Event模型进行改进,将拼接四棱锥碰撞盒代替原长方体碰撞盒,曲面间隔层代替平面间隔层,建立通用航空器碰撞风险模型。最后将塞斯纳172及运5B通用航空器作为实例对所建模型进行验证,结果表明,在两组均采用广义帕累托分布的条件下,改进后Event模型碰撞风险值分别为改进前的31.65%、14.98%,碰撞风险值较改进前大大减少,结果精度更高,能更好地评估交叉航路碰撞风险。 展开更多
关键词 event模型 碰撞风险 曲面间隔层 广义帕累托分布
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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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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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Volumetric changes in the focal areas of seismic events corresponding to destress blasting 被引量:2
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作者 P.Konicek J.Schreiber L.Nazarova 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第4期541-547,共7页
The typical development of total volumetric change in the focal areas of seismic events,corresponding to destress blasting,is characterized as an explosive phase followed by an implosive phase and with alternating add... The typical development of total volumetric change in the focal areas of seismic events,corresponding to destress blasting,is characterized as an explosive phase followed by an implosive phase and with alternating additional phases following on from that.In a few cases,a non-typical development of volumetric change was identified,where the first phase was implosive and the second phase,explosive.This development is mainly typical for induced seismic events recorded during mining,not for destress blasting.Seismic events were recorded during longwall mining in the Czech part of the Upper Silesian Coal Basin,where the destress blasting technique is used as a rockburst prevention active measure.Kinematic source processes in the focal areas of selected seismic events were analyzed by the seismic moment tensor inversion method,as well as by studying geomechanical rock mass conditions at the localities of the seismic events.The main goal of the analysis was to attempt to identify the reasons for non-typical development of volumetric changes in these cases.Volumetric changes were analyzed for seismic events with energy greater than 104 J,recorded in the period of time from 1993 to 2009(1109 events).80%(891)of the recorded seismic events were induced seismic events that were registered during longwall mining and 20%(218)corresponded to destress blasting events.Research shows that the main reason for the non-typical development of volumetric changes in the focal areas of seismic events is an association with destress blasting in the rock mass,which is very close to rock mass overstressing.The detonation of explosives in boreholes,which would dominate the first phase of volumetric changes,probably obscured stress release in the rock mass,as manifested in the first implosion phase of the volumetric changes in this case. 展开更多
关键词 Destress BLASTING SEISMIC event VOLUMETRIC CHANGES Stress release
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The characteristics of clusters of weather and extreme climate events in China during the past 50 years 被引量:2
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作者 Yang Ping Hou Wei Feng Guo-Lin 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期549-557,共9页
The pick-up algorithm by the k-th order cluster for the closest distance is used in the fields of weather and climactic events, and the technical terms clustered index and high clustered region are defined to investig... The pick-up algorithm by the k-th order cluster for the closest distance is used in the fields of weather and climactic events, and the technical terms clustered index and high clustered region are defined to investigate their temporal and spatial distribution characteristics in China during the past 50 years. The results show that the contribution of extreme high-temperature event clusters changed in the period from the 1960s to the 1970s, and its strength was enhanced. On the other hand, the decreasing trend in the clusters of low-temperature extremes can be taken as a signal for warmer winters to follow in the decadal time scale. Torrential rain and heavy rainfall clusters have both been lessened in the past 50 years, and have different cluster characteristics because of their definitions. Regions with high clustered indexes are concentrated in southern China. The spatial evolution of the heavy rainfall clusters reveals that clustered heavy rainfall has played an important role in the rain-belt pattern over China during the last 50 years. 展开更多
关键词 extreme event CLUSTERS decadal clustered index
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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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Word-Representation-Based Method for Extracting Organizational Events from Online Media 被引量:1
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作者 Jun-Qiang Zhang Xiong-Wen Deng Yu Qian 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第4期407-412,共6页
Online social media exhibit massive organizational event relevant messages, and the well categorized event information can be useful in many real-world applications. In this paper, we propose a research framework to e... Online social media exhibit massive organizational event relevant messages, and the well categorized event information can be useful in many real-world applications. In this paper, we propose a research framework to extract high quality event information from massive online media data. The main contributions lie in two aspects: First, we present an event-extraction and event-categorization system for online media data; second, we present a novel approach for both discovering important event categories and classifying extracted events based on word representation and clustering model. Experimental results with real dataset show that the proposed framework is effective to extract high quality event information. 展开更多
关键词 event detection social media text mining word representation
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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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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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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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Comments to "Neutrophil-to-lymphocyte ratio compared to N-terminal pro- brain natriuretic peptide as a prognostic marker of adverse events in elderly patients with chronic heart failure" 被引量:3
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作者 Kahraman Cosansu Cagin Mustafa Ureyen 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第10期657-658,共2页
We have read the article which entitled "Neutrophil-to- lymphocyte ratio compared to N-terminal pro-brain natri- uretic peptide as a prognostic marker of adverse events in elderly patients with chronic heart failure... We have read the article which entitled "Neutrophil-to- lymphocyte ratio compared to N-terminal pro-brain natri- uretic peptide as a prognostic marker of adverse events in elderly patients with chronic heart failure" published in Journal of Geriatric Cardiology with great interest, However, we have some comments regarding this study. 展开更多
关键词 Atrial fibrillation C-reactive protein Major cardiovascular event Neutrophil-to-lymphocyte ratio
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Relationship between the rock mass deformation and places of occurrence of seismological events 被引量:2
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作者 MAKOWKA Janusz KABIESZ Jozef DOU Lin-ming 《Mining Science and Technology》 EI CAS 2009年第5期580-584,共5页
Static effort of rock mass very rarely causes of rock burst in polish coal mines. Rock bursts with source in the seismic tremor within the roof rock layers are prevailing. A seismic tremor is an effect of rupture or s... Static effort of rock mass very rarely causes of rock burst in polish coal mines. Rock bursts with source in the seismic tremor within the roof rock layers are prevailing. A seismic tremor is an effect of rupture or sliding in roof layers above the exploited panel in coal seam, sometime in a distance from actual exploitation. Sliding, as a rule occurs in fault zone and tremors in it are expected, but monolithic layer rupture is very hard to predict. In a past few years a practice of analyzing state of deformation in high energy seismic tremors zones has been employed. It let gathering experience thanks to witch determination of dangerous shape of reformatted roof is possible. In the paper some typical forms of roof rocks deformations leading to seismic tremor occurrence will be presented. In general these are various types of multidirectional rock layers bending. Real examples of seismic events and rock bursts will be shown. 展开更多
关键词 rock mass deformation seismological event
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Responses of some landscape trees to the drought and high temperature events during 2006 and 2007 in Yamaguchi, Japan 被引量:3
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作者 WANG Fei Haruhiko Yamamoto Yasuomi Ibaraki 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第3期254-260,共7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 re- ducing 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 (Comus 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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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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Investigation of the J-TEXT plasma events by k-means clustering algorithm 被引量:1
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作者 李建超 张晓卿 +11 位作者 张昱 Abba Alhaji BALA 柳惠平 周帼红 王能超 李达 陈忠勇 杨州军 陈志鹏 董蛟龙 丁永华 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第8期38-43,共6页
Various types of plasma events emerge in specific parameter ranges and exhibit similar characteristics in diagnostic signals,which can be applied to identify these events.A semisupervised machine learning algorithm,th... Various types of plasma events emerge in specific parameter ranges and exhibit similar characteristics in diagnostic signals,which can be applied to identify these events.A semisupervised machine learning algorithm,the k-means clustering algorithm,is utilized to investigate and identify plasma events in the J-TEXT plasma.This method can cluster diverse plasma events with homogeneous features,and then these events can be identified if given few manually labeled examples based on physical understanding.A survey of clustered events reveals that the k-means algorithm can make plasma events(rotating tearing mode,sawtooth oscillations,and locked mode)gathering in Euclidean space composed of multi-dimensional diagnostic data,like soft x-ray emission intensity,edge toroidal rotation velocity,the Mirnov signal amplitude and so on.Based on the cluster analysis results,an approximate analytical model is proposed to rapidly identify plasma events in the J-TEXT plasma.The cluster analysis method is conducive to data markers of massive diagnostic data. 展开更多
关键词 K-MEANS cluster analysis plasma event machine learning
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