S波影区地震精确定位的研究

长期的地震观测发现,北京地震台记录到的S波影区地震存在定位误差大的现象.由于来自震中距9°～36°的地震经过了低速层,造成了S波不发育.所以S波影区地震多用LG波来确定震中距.造成影区地震定位偏差大的现象有两个原因:①长期以来多是用短周期记录来区分LG1和LG2,定位偏差较大;②有的影区地震,S波也少许发育,但用S波来定位也存在定位偏差大的现象.为此搜集了北京地震台记录到的影区地震,通过NCDSN仿真成SK记录,通过理论震中距的比较,找到了准确定位影区地震的LG2识别位置.     

Probabilistic outlier detection for sparse multivariate geotechnical site investigation data using Bayesian learning

Various uncertainties arising during acquisition process of geoscience data may result in anomalous data instances(i.e.,outliers)that do not conform with the expected pattern of regular data instances.With sparse multivariate data obtained from geotechnical site investigation,it is impossible to identify outliers with certainty due to the distortion of statistics of geotechnical parameters caused by outliers and their associated statistical uncertainty resulted from data sparsity.This paper develops a probabilistic outlier detection method for sparse multivariate data obtained from geotechnical site investigation.The proposed approach quantifies the outlying probability of each data instance based on Mahalanobis distance and determines outliers as those data instances with outlying probabilities greater than 0.5.It tackles the distortion issue of statistics estimated from the dataset with outliers by a re-sampling technique and accounts,rationally,for the statistical uncertainty by Bayesian machine learning.Moreover,the proposed approach also suggests an exclusive method to determine outlying components of each outlier.The proposed approach is illustrated and verified using simulated and real-life dataset.It showed that the proposed approach properly identifies outliers among sparse multivariate data and their corresponding outlying components in a probabilistic manner.It can significantly reduce the masking effect(i.e.,missing some actual outliers due to the distortion of statistics by the outliers and statistical uncertainty).It also found that outliers among sparse multivariate data instances affect significantly the construction of multivariate distribution of geotechnical parameters for uncertainty quantification.This emphasizes the necessity of data cleaning process(e.g.,outlier detection)for uncertainty quantification based on geoscience data.     

EFFECT OF COARSENING OF SURFACE BED MATERIAL ON NON-EQUILIBRIUM SEDIMENT TRANSPORT PROCESS DURING RIVER DEGRADATION

1INTRODUCTIONNon-equilibriumsedimenttransportina"at'Uralstreamwithnon-uniformbedmaterialisasubjectofilltensiveresearch.ThesedimentconcentrationmaybenotequaltothetransportcapacityofflowinanalluvialrivedItgraduallyapproachesequilibriumbydegradationoraggradationinalongdistance.usuallyover100kilometers.Thisproblemisofgreatimportancetothepredictionofthedistributionoferosionordepositionalongachannel,especiallyforlargeriversinChina.Scientistsstudiednonequilibriumsedimenttransportandthemainresul…     

大井间距井间地震观测试验

介绍了井间地震数据采集方面取得的最新进展．为了使我国井间地震技术实用化,开展了大井间距井间地震数据采集试验．通过地面浅井激发深井接收、深井激发深井接收、不同炸药量、不同传播距离试验,确定了井间地震观测参数．应用改进后的井中安全炸药震源、一个三分量井中检波器和常规数据记录系统,在陕北顺宁油田的顺3井、顺4井和顺5井3口生产井中成功采集到两对大井间距、深井、油井中的井间地震资料,两对井的井距分别为307．92m和470．36m,采集井段为904．31-1272．32m．共设计了4种观测方式,采集到800多炮井间地震记录,对油井无损害．改进型井中安全炸药震源在使用效率和寿命方面有显著提高,可用于商业性并间地震数据采集．     

青岛市中港东区码头改造工程水下爆岩施工

青岛市中港东区码头工程水下爆岩工程量１．３万m^3,施工中采用了多段微差爆破,毫秒延迟爆破,导爆管起爆等多项为先进和成熟的施工技术,合理的施工组织,完善的施工管理,保证了工程质量,加快了工程进度。     

近距离照射联合贻贝提取物对荷瘤鼠治疗效果的研究

观察了近距离照射联合贻贝提取物对Ｕ１４鼠免疫功能的影响,以期探讨贻贝提取物在放射治疗中的作用。结果表明,贻贝提取物使荷瘤鼠因近距离照射而下降的免疫指标明显回升,包括脾脏ＮＫ细胞杀伤活性,丝裂原诱发的淋巴细胞转化强度和外周血白细胞总数及脾指数,亦有效增强放疗的治疗效果。     

黄河三角洲冬半年大风预报系统

利用１９９０～１９９７年高空实况场资料作历史样本库,进行相关分析,提取典型因子场,在运用历史样本进行分型、分级的基础上,再利用与Ｔ１０６Ｌ１９数值预报产品典型因大场的平均域块距离最优相似方法,制作黄河三角洲冬半年沿海、内陆大风客观预报,经试用效果较好。     

Determination of Scenario Earthquakes for Zigong City

Ujsing deterministic methods in combination with probabilistic methods,the authors havestudied in detail the seismogeological background,seismogfnic faults and their abilities ingenerating earthquakes,the temporal and spatial distribution features of seismicity;predicted the seismicity tendency in future 50 years;and studied the expected magnitude andexpected distance of destructive earthquakes that may attack Zigong City.On such a basis,2scenario earthquakes have been determined for Zigong City.The results would be helphl forthe lecal government and authorities to work out a great earthquake emergency pre-plan andto estaplish the great earthquake fast-response system.