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用中周期面波资料作全球m_W≥4.5中强地震的CmT分析

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世界地震译丛 1999年第3期30卷 54-64页

作者： R.Arvidsson g.ekstrm 许健生中国地震局兰州地震研究所

给出了计算中强地震矩心矩张量(CmT)解的一种新方法。在这种新的算法中,对标准的哈佛大学CmT方法做了修正,用中周期面波反演震源参数。在最新的全球相速度分布图上,用内插法可以获得周期40～50s的远震面波的频散曲线。用已知震源机制的2... 详细信息

给出了计算中强地震矩心矩张量(CmT)解的一种新方法。在这种新的算法中,对标准的哈佛大学CmT方法做了修正,用中周期面波反演震源参数。在最新的全球相速度分布图上,用内插法可以获得周期40～50s的远震面波的频散曲线。用已知震源机制的20个中强地震(5.2≤m_W≤7.2)对这种方法作了检验。由新方法求得的震源机制和以前得到的结果相似,甚至对于叠加了噪音且震级较小的模拟地震(m_W～4.5)也是如此。这种反演方法被应用到1993年的克拉马斯福尔斯主震和余震序列上,经与以前的结果相比较效果非常好。用新的分析方法给出了1995年前半年发生在希腊及其周围地区肘m_W≥4.5地震的震源机制解。

关键词：地震波中周期面波资料中强地震 CmT分析

全球CmT计划2004～2010:13017个地震的矩心矩张量

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世界地震译丛 2012年第5期43卷 20-30页

作者： g.ekstrm m.Nettles A.m.Dziewonski 赵仲和中国地震台网中心

给出了反映7年(2004～2010)间全球地震活动性的地震矩张量。这些结果是全球矩心矩张量(gCmT)计划的产品。该计划维护并扩展了自1976年地震开始的全球地震矩张量目录。自2004年的地震开始,全球矩心矩张量分析利用了中周期面波传播特性分... 详细信息

给出了反映7年(2004～2010)间全球地震活动性的地震矩张量。这些结果是全球矩心矩张量(gCmT)计划的产品。该计划维护并扩展了自1976年地震开始的全球地震矩张量目录。自2004年的地震开始,全球矩心矩张量分析利用了中周期面波传播特性分布图研究取得的进步,将这些中周期面波包括到矩张量反演中。对矩心矩张量算法的这一修正使得有可能全球均一性地确定小到mW=5.0地震的矩张量。对于2004～2010年时间段,报告了13017个新的矩心矩张量。

关键词：全球地震活动性矩心矩张量地震

2001年11月14日青藏可可西里(昆仑山)地震:破裂穿过大的张性阶跃带(二)

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世界地震译丛 2005年第4期36卷 46-57页

作者： m.Antolik R E.Abercrombie g.ekstrm 何振德防灾技术高等专科学校

3 体波反演：滑动分布在本节，我们基于点源结果和观测的地表破裂几何形状研制了可可西里地震的滑动分布模型。类似于其他的研究（如Wald and Heaton，1994；Kaverina et al，2002：An—tolik and Dreger，2003），我们使用有限断层方... 详细信息

3 体波反演：滑动分布在本节，我们基于点源结果和观测的地表破裂几何形状研制了可可西里地震的滑动分布模型。类似于其他的研究（如Wald and Heaton，1994；Kaverina et al，2002：An—tolik and Dreger，2003），我们使用有限断层方法对远震P波的子集进行反演。

关键词：可可西里地表破裂地震昆仑山阶跃张性青藏分布模型几何形状

2001年11月14日青藏可可西里(昆仑山) 地震:破裂穿过大的张性阶跃带(一)

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世界地震译丛 2005年第3期36卷 31-41页

作者： m.Antolik R E.Abercrombie g.ekstrm 万永革防灾技术高等专科学校

2001年11月14日青藏可可西里地震(mw7．8)造成青藏北部的西昆仑断层破裂约400 km。我们对全球地震台网记录的P和SH波采用两种反演方法复原时空破裂过程。观测到的地表破裂由两个走滑段组成,其间有张性阶跃带,范围约长45 km, 宽10 km以... 详细信息

2001年11月14日青藏可可西里地震(mw7．8)造成青藏北部的西昆仑断层破裂约400 km。我们对全球地震台网记录的P和SH波采用两种反演方法复原时空破裂过程。观测到的地表破裂由两个走滑段组成,其间有张性阶跃带,范围约长45 km, 宽10 km以上。虽然在阶跃带中的地堑系内几乎没有观测到地表破裂,但我们的结果表明破裂并没有跳过这个大的空挡,而是连续地穿过地堑。地震以小的走滑子事件开始,推测其沿着两个断层段的最西部发展。5 s之后,发生一个约相同大小、具有较大正断层分量的斜断层破裂子事件,其位置可能就在地堑内。倾斜滑动事件可能使破裂转移到主昆仑断层上。主要的矩释放在破裂起始约18 s、沿昆仑断层向东传播350 km之后发生。在这个断层段上滑动非常不均匀,在初始的200 km平均约2 m,在随后的 50 km内突然增加,达到最大值7．5 m,然后又很快下降。沿主段的平均破裂速度较高 (-3．6 km·s-1),可能超过了该区的剪切波速度。mw7．8级可可西里地震与2002年 11月mw7．9级迪纳利断层(阿拉斯加)地震相比,具有较长的地表破裂,较快的平均破裂速度及释放了较多的能量,并且可能具有较低的平均破裂能量。证据表明,破裂前缘速度过了最大滑动点后明显下降,这意味着断层两端的摩擦强度有很大不同。

关键词： 2001年11月可可西里阶跃青藏张性昆仑山 2002年11月时空破裂过程全球地震台网地表破裂断层破裂剪切波速度反演方法阿拉斯加摩擦强度子事件断层段平均西昆仑 SH波地堑系正断层 18s 不均匀最大值走滑

magnesium oxide(mgO)nanoadsorbents in wastewater treatment:A comprehensive review

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Journal of magnesium and Alloys 2024年第5期12卷 1709-1773页

作者： H.C.S.Perera V.gurunanthanan Anoop Singh m.m.m.g.P.g.mantilaka g.Das Sandeep Arya Department of Physics Khalifa UniversityAbu Dhabi12788United Arab Emirates Postgraduate Institute of Science University of PeradeniyaPeradeniyaSri Lanka Department of Humanities and Sciences Guru Nanak Institutions Technical CampusIbrahimpatnamHyderabad501506India Centre for global Health Research Saveetha Medical College and HospitalsSaveetha Institute of Medical and Technical SciencesChennai602105Tamil NaduIndia Department of Physics University of JammuJammu and Kashmir180006India

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge,necessitating effective and sustainable separation *** review article provides a detailed examination of magnesium oxide(mgO)nanoparticles as an innovative nanoadsorbent for wastewater treatment,with a specific focus on heavy metal and dye *** review comprehensively explores various aspects of mgO nanoparticles,including their structural characteristics and synthesis *** article delves into the morphology and crystallographic arrangement of mgO nanoparticles,offering insights into their structural *** the complexity of adsorption processes,the review identifies and analyzes parameters influencing the adsorption efficiency of mgO nanoparticles,such as temperature,pH,contact time,initial concentration,and co-existing *** interplay between these parameters and the adsorption capability of mgO nanoparticles emphasizes the importance of optimizing operational ***,the review assesses various synthesis methods for mgO nanoparticles,including sol-gel,hydrothermal,precipitation,green synthesis,solvothermal,and template-assisted *** discusses the advantages,limitations,and resulting nanoparticle characteristics of each method,enabling readers to grasp the implications of synthesis processes on adsorption *** comprehensive review consolidates current insights into the effectiveness of mgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to mgO ***,there is a need to investigate the use of mgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： mgO nanoparticles Nanoadsorbent Wastewater treatment Heavy metals Dye separation Adsorption Synthesis methods

Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method

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Nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： m.Hajipour g.R.Ansarifar Department of Nuclear Engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear power plants exhibit non-linear and time-variable ***,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual *** an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the *** this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled *** an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power *** point kinetics equations with three groups of delayed neutrons were used in the ***-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous *** controlled parameters were reactor power,steam temperature,and ***,for these parameters,the PI controller had certain instabilities in the presence of *** classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering *** was highly accurate and stable and had a small computational *** reality,it followed the desired values without oscillations and chattering.

关键词： Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model

2004年12月26日苏门答腊—安达曼特大地震

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世界地震译丛 2005年第6期36卷 5-14页

作者： T.LAY H.KANAmORI C.J.AmmON m.NETTLES S.N.WARD R.C.ASTER S.L.BECK S.L.BILEK m.R.BRUDZINSKI R.BUTLER H.R.DESHON g.ekstrm K.SATAKE S.SIPKIN 石玉涛中国地震局地震预测研究所

发生在2004年12月26日（mw=9．1～9．3级）和2005年3月28日（mw=8．6级）的地震是过去40年中最大的两次地震，它们在欧亚大陆板块的东南部和印度-澳大利亚板块之间裂开一条长达1600km的断层。其中第一次地震引发的海啸吞噬了28．3万多... 详细信息

发生在2004年12月26日（mw=9．1～9．3级）和2005年3月28日（mw=8．6级）的地震是过去40年中最大的两次地震，它们在欧亚大陆板块的东南部和印度-澳大利亚板块之间裂开一条长达1600km的断层。其中第一次地震引发的海啸吞噬了28．3万多人的性命。苏门答腊岛班达亚奇附近的断层滑动了15m，但是在其北边，沿着尼科巴群岛和安达曼群岛，断层快速滑动的距离则小了很多。海啸和测地学的观测表明，在50min或更长的时间范围内北部的断层发生了更多的缓慢滑动。

关键词：苏门答腊大地震断层滑动大陆板块澳大利亚时间范围东南部测地学海啸群岛

Investigation of the transformation of organic matter of carbonate deposits of the Semiluksky-mendymsky horizon under hydrothermal conditions

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Petroleum 2024年第2期10卷 216-223页

作者： S.m.Petrov A.I.Lakhova E.g.moiseeva A.g.Safiulina Institute of Petroleum Chemistry and NanotechnologiesKazan National Research Technological UniversityKazan420015Russia Institute of geology and Oil and gas Technologies Kazan Federal UniversityKazan420008Russia

The paper presents the results of studies on the transformation of the organic matter of siliceous-clayey carbonate rocks of the Semiluksko-mendymsky horizon of the Romashkino oil field in a hydrothermal fluid for an hour(with a water-to-rock ratio of 33)at 340℃and 380℃and pressu res of 17 and 20 *** a result of hydrothermal treatment,at 340℃and 17 mPa,based on nitrogen porosimetry and electron microscopy data,transformations of rock-forming minerals in the rock are *** lead to an increase in the volume and average diameter of mesopores in it and the formation of micropores,as well,which improve its filtration *** the same time,the amount of kerogen in the composition of the organic matter decreases and the yield of the petroleum hydrocarbon extract increases,in which,according to the SARA analysis,the content of asphaltenes increases and the content of resins,aromatic and saturated hydrocarbons *** the composition of aroatic hydrocarbons,the proportion of a lkyltri methyl benzenes and dibenzothiophenes increases,phenanthrene homologues appear,and in the composition of saturated hydrocarbons,the amount of iso-structure alkanes decreases relative to the content of linear *** the temperature and pressure of the hydrothermal fluid to 380℃and 20 mPa increases the degree of kerogen conversion from 12.4%to 23.6%.At the same time,changes occurring in the component composition of petroleum hydrocarbon extracts remains similar to the experiments carried out at 340℃and 17 mPa;the content of naphthalenes decreases,the content of dibenzothiophenes increases and C_(11)-C_(17),C_(19)-C_(22)alkyltrimethylbenzenes *** to IR spectroscopy,with increasing temperature and pressure of the hydrothermal fluid the intensity of the absorption bands of the aromatic ring,aliphatic fragments,and oxygen-containing groups increases in resins;the structural-group composition of asphaltenes changes little:aromaticity and the content of conde

关键词： Carbonate deposits Organic matter Hydrothermal fluid mobile hydrocarbons

Automatic Rule Discovery for Data Transformation Using Fusion of Diversified Feature Formats

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Computers, materials & Continua 2024年第7期80卷 695-713页

作者： g.Sunil Santhosh Kumar m.Rudra Kumar Department of CSE Jawaharlal Nehru Technological UniversityAnantapur515002India Department of CSE Marri Laxman Reddy Institute of Technology and ManagementHyderabad500043India Department of Information Technology Mahatma Gandhi Institute of TechnologyHyderabad500075India

This article presents an innovative approach to automatic rule discovery for data transformation tasks leveraging XgBoost,a machine learning algorithm renowned for its efficiency and *** framework proposed herein utilizes the fusion of diversified feature formats,specifically,metadata,textual,and pattern *** goal is to enhance the system’s ability to discern and generalize transformation rules fromsource to destination formats in varied ***,the article delves into the methodology for extracting these distinct features from raw data and the pre-processing steps undertaken to prepare the data for the *** sections expound on the mechanism of feature optimization using Recursive Feature Elimination(RFE)with linear regression,aiming to retain the most contributive features and eliminate redundant or less significant *** core of the research revolves around the deployment of the XgBoostmodel for training,using the prepared and optimized feature *** article presents a detailed overview of the mathematical model and algorithmic steps behind this ***,the process of rule discovery(prediction phase)by the trained XgBoost model is explained,underscoring its role in real-time,automated data *** employingmachine learning and particularly,the XgBoost model in the context of Business Rule Engine(BRE)data transformation,the article underscores a paradigm shift towardsmore scalable,efficient,and less human-dependent data transformation *** research opens doors for further exploration into automated rule discovery systems and their applications in various sectors.

关键词： XgBoost business rule engine machine learning categorical query language humanitarian computing environment