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2024年1月23日乌什M_(S)7.1地震前新疆地电优势方位角变化特征分析
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作者 刘海洋 饶文 +1 位作者 徐衍刚 艾萨·伊斯马伊力 《内陆地震》 2024年第2期182-193,共12页
通过对2024年1月23日乌什M_(S)7.1地震前新疆境内5个地电台站观测数据的回溯性分析,计算地震前各台站地电优势方位角,总结数据变化特征,发现地震前各台站地电优势方位角均出现了不同程度的异常变化,异常表现为分散、集中、偏转和跃变的... 通过对2024年1月23日乌什M_(S)7.1地震前新疆境内5个地电台站观测数据的回溯性分析,计算地震前各台站地电优势方位角,总结数据变化特征,发现地震前各台站地电优势方位角均出现了不同程度的异常变化,异常表现为分散、集中、偏转和跃变的特征。其中震中附近的乌什台、温泉台地电优势方位角异常在时间上具有准同步变化。地震前震中500 km范围内的乌什、温泉、和田台不仅存在不同方位间相关系数的准同步下降变化,而且极化方位也出现了相似的线性极化增强现象,且乌什、和田台优势方位角的异常变化均呈现出向主压应力集中现象,说明在乌什M_(S)7.1地震前乌什、温泉、和田台观测到的地电数据变化,同此次地震具有一定机理上的联系。 展开更多
关键词 乌什M_(s)7.1地震 地电场 优势方位角 变化特性 震源机制
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The Number of Minimum Roman and Minimum Total Dominating Sets for Some Chessboard Graphs
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作者 Paul A. Burchett 《Open Journal of Discrete Mathematics》 2020年第1期31-44,共14页
In this paper, both the roman domination number and the number of minimum roman dominating sets are found for any rectangular rook’s graph. In a similar fashion, the roman domination number and the number of minimum ... In this paper, both the roman domination number and the number of minimum roman dominating sets are found for any rectangular rook’s graph. In a similar fashion, the roman domination number and the number of minimum roman dominating sets are found on the square bishop’s graph for odd board sizes. Also found are the number of minimum total dominating sets associated with the light-colored squares when n?&#8801;1(mod12)? (with n>1), and same for the dark-colored squares when n?&#8801;7(mod12) . 展开更多
关键词 TOTAL dominATION ROman dominATION Bishop’s GRAPH Rook’s GRAPH Chess
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On Classes of Matrices with Variants of the Diagonal Dominance Property
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作者 Farid O. Farid 《Advances in Linear Algebra & Matrix Theory》 2017年第2期37-65,共29页
We study the relations between several classes of matrices with variants of the diagonal dominance property, and identify those classes which form pairs of incomparable classes. For an incomparable pair (X1,X2) of cla... We study the relations between several classes of matrices with variants of the diagonal dominance property, and identify those classes which form pairs of incomparable classes. For an incomparable pair (X1,X2) of classes of matrices with variants of the diagonal dominance property, we also study the problem of providing sufficient conditions for the matrices in Xi to be in Xj with {i,j}={1,2}. The article is a continuation of a series of articles on the topic and related topics by the author;see [1][2][3][4]. 展开更多
关键词 DOUBLY Diagonally dominANT Generalized Diagonally dominANT (s1 s2) separation Induced Diagonally dominANT Row-Column Diagonally dominANT with Index &alpha
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2021年青海玛多MS7.4地震前大武台地电场优势方位角异常特征分析 被引量:6
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作者 赵玉红 苏维刚 +3 位作者 冯丽丽 李霞 刘磊 孙玺皓 《地震学报》 CSCD 北大核心 2023年第1期76-83,共8页
为了深入了解2021年5月22日青海省玛多M_(S)7.4地震前是否存在地震电信号,本文利用地电场优势方位角方法对大武地电场的原始资料进行了分析,获得了玛多地震前震中附近场地的岩体裂隙结构变化特征,并结合本次地震震中500 km范围内八个地... 为了深入了解2021年5月22日青海省玛多M_(S)7.4地震前是否存在地震电信号,本文利用地电场优势方位角方法对大武地电场的原始资料进行了分析,获得了玛多地震前震中附近场地的岩体裂隙结构变化特征,并结合本次地震震中500 km范围内八个地电场台站的岩体裂隙结构变化和该台记录到的以往震例中大武台地电场优势方位角异常变化与中强地震之间的关系进行了综合分析。结果显示:大武台新旧两套地电场数据的地电场优势方位角在震前11个月出现了显著的同步偏转现象,其中大武旧台在震前两个月优势方位角再次出现大幅度上升,异常特征主要表现为优势方位角出现同步快速偏转,最大偏转达到45°—90°;处于同一次级地块的甘孜台、玛曲台与大武台出现准同步异常现象,而其它次级地块上的台站均无异常出现,表明异常响应受到区域构造的影响。再结合大武台地电场使用该方法分析的以往震例表明:大武台的地电场优势方位角异常在中强地震前具有较好的中短期指示意义。 展开更多
关键词 大地电场 玛多 M_(s)7.4 地震 优势方位角 大武地震台 异常特征
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Hydraulic model with roughness coefficient updating method based on Kalman filter for channel flood forecast 被引量:4
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作者 Hong-jun BAO Lin-na ZHAO 《Water Science and Engineering》 EI CAS 2011年第1期13-23,共11页
A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness upda... A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness updating technique was developed using the Kalman filter method to update Manning's roughness coefficient at each time step of the calculation processes. Channel shapes were simplified as rectangles, triangles, and parabolas, and the relationships between hydraulic radius and water depth were developed for plain rivers. Based on the relationship between the Froude number and the inertia terms of the momentum equation in the Saint-Venant equations, the relationship between Manning's roughness coefficient and water depth was obtained. Using the channel of the Huaihe River from Wangjiaba to Lutaizi stations as a case, to test the performance and rationality of the present flood routing model, the original hydraulic model was compared with the developed model. Results show that the stage hydrographs calculated by the developed flood routing model with the updated Manning's roughness coefficient have a good agreement with the observed stage hydrographs. This model performs better than the original hydraulic model. 展开更多
关键词 flood routing manning's roughness coefficient updating method Kalman filter Froude number saint-Venant equations hydraulic model
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CONVEX CONCENTRATION INEQUALITIES FOR CONTINUOUS GAS AND STOCHASTIC DOMINATION 被引量:1
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作者 马宇韬 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1461-1468,共8页
In this article, we consider the continuous gas in a bounded domain ∧ of R^+ or R^d described by a Gibbsian probability measure μη∧ associated with a pair interaction φ, the inverse temperature β, the activity... In this article, we consider the continuous gas in a bounded domain ∧ of R^+ or R^d described by a Gibbsian probability measure μη∧ associated with a pair interaction φ, the inverse temperature β, the activity z 〉 0, and the boundary condition η. Define F ∫ωf(s)wA(ds). Applying the generalized Ito's formula for forward-backward martingales (see Klein et M. [5]), we obtain convex concentration inequalities for F with respect to the Gibbs measure μη∧. On the other hand, by FKG inequality on the Poisson space, we also give a new simple argument for the stochastic domination for the Gibbs measure. 展开更多
关键词 continuous gas Gibbs measure convex concentration inequality Ito's formula stochastic domination
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New Criteria for Judging Generalized Strictly Diagonally Dominant Matrix 被引量:1
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作者 ZHANG Jin-song 《Chinese Quarterly Journal of Mathematics》 2015年第2期166-171,共6页
Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not gen... Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not generalized strictly diagonally dominant matrix.In this paper, by using the properties of α-chain diagonally dominant matrix, we obtain new criteria for judging generalized strictly diagonally dominant matrix, which enlarge the identification range. 展开更多
关键词 generalized strictly diagonally dominant matrix CRITERIA α-chain diagonally dominant matrix
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ELECTRON SPIN RESONANCE DATING FOR THE AGE OF PEKING-MAN, LOC.1, ZHOUKOUDIAN, BEIJING
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作者 黄培华 金嗣昭 +5 位作者 梁又任 陆仲家 郑丽珍 袁振新 蔡炳溪 方超萌 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第3期169-173,共5页
In this paper, we used ESR dating method to measure the accumulative dose of the fossil teeth samples, which are contemporaneous with the Peking-Man. The internal annual dose rate of samples are got by neutron activat... In this paper, we used ESR dating method to measure the accumulative dose of the fossil teeth samples, which are contemporaneous with the Peking-Man. The internal annual dose rate of samples are got by neutron activation analysis and the environmental annual dose rate by highly sensitive TL dosimeters to be embedded in cave deposits in the site. The results of ESR dating are corresponded with the dating results obtained by U-series, FT, TL and paleomagnetic stratigraphical methods on the 3rd, 4th, 7th and 10th layers. Calculation of using different models, the close-equilibrium model, the linear uranium accumulation model and radon loss-linear uranium accumulation model, for travertine, deer teeth and rhinoceros tooth, we obtained the age of the First Peking- Man in the nth layer is 578 ka and gave ages of other layers, from the 1st to the 13th layer in Peking- Man site. 展开更多
关键词 EsR DATING Peking- mans age
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The types and characteristics of man-induced sediment disaster
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作者 JIN Desheng, SHI Changxing, CHEN Hao, ZHANG Ouyang(Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第4期495-504,共10页
The man-induced sediment disaster includes material erosion, transportation and accumulation by human activities. It possesses special attribute in sociology and disaster science. In accordance with human activities, ... The man-induced sediment disaster includes material erosion, transportation and accumulation by human activities. It possesses special attribute in sociology and disaster science. In accordance with human activities, geomorphologic location, behavior and particular, the man-induced sediment disaster can be divided into 4 types: the drainage network, slope and gully, channel and plain-estuary-coastline. Each type includes erosion, transportation, accumulation, complexity and cascading. Based on human activity, geomorphology, sediment mechanics and catastrophology, the man-induced sediment disaster is characterized as follows: (1) accelerating tendency with geographical zoning back-ground; (2) non-order characters by blind action without special technical training; (3) gradually and sharply changing with human environment vibration; and (4) complexity and non-linear figure, etc. One of the reasons leading to man-induced sediment disaster is human environment vibration. 展开更多
关键词 mans dynamics sediment disaster type CHARACTER
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Anderson's Motives for Exploring Man's Frustration
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作者 赵春玲 《科技信息》 2010年第8期I0147-I0148,共2页
Man's frustration is a dominant theme in Anderson's short stories.It is the condensation of his impressions of American life.His motives for exploring the problem include:to reveal the painful experience,feeli... Man's frustration is a dominant theme in Anderson's short stories.It is the condensation of his impressions of American life.His motives for exploring the problem include:to reveal the painful experience,feeling and situation of ordinary people during the economic,social and cultural transformations of America;to remind the reader of the choking effects of outworn conventional morality and the destructive effects of modern industrial materialism;to draw the reader's attention to the emotional life of the ordinary people;and to express his own views on and attitudes toward humanity and society. 展开更多
关键词 美国 文学 研究 发展
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A Man's Return to His First Hometown
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作者 The past becomes present for a man who wouldn’t forget.By HU QIHUA 《China Today》 1999年第1期56-59,共4页
A62-year-olddreambecamerealitywhenJosephS.FermtraveledhalfwayaroundtheglobefromtheUnitedStatestoChinatomeethischildhoodplaymatesinacountrytownineastChina'sShandongProvince.Fermwasoneyearoldwhenhismissionaryparents... A62-year-olddreambecamerealitywhenJosephS.FermtraveledhalfwayaroundtheglobefromtheUnitedStatestoChinatomeethischildhoodplaymatesinacountrytownineastChina'sShandongProvince.FermwasoneyearoldwhenhismissionaryparentssettledinLongshan.Theyleftin1936whenF... 展开更多
关键词 man A mans Return to His First Hometown In
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Metallic Reserves of Submarine Manganese Nodules to be Estimated and Harnessed Prudently: Evidence from China's Jiaolong Manned Submersible
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作者 Hao Ziguo Fei Hongcai +1 位作者 Liu Lian Susan Turner 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第4期1179-1180,共2页
Since the discovery of oceanic manganese nodules during the expedition of the British ocean-going ship Challenger from 1872 to 1876, research and development for seabed manganese nodules have never ceased owing to the... Since the discovery of oceanic manganese nodules during the expedition of the British ocean-going ship Challenger from 1872 to 1876, research and development for seabed manganese nodules have never ceased owing to the huge economic inducements. Manganese nodules are the black or dark brown, spherical or massive Mn-bearing ores, deposits of which are found on the sea bottom. The nodules are a mixture of silicate and insoluble potassium permanganates (also with sub-Ti, Fe and Na permanganates) that contain more than 30 kinds of metallic elements, among which those of greatest economic interest are Mn (27-30%), Ni(1.25-1.5%), Cu(1- 1.4%), Co(0.2- 0.25 %), Fe, Si, and AI, with minor amounts of Ca, Na, K, Ti, B, H and O. 展开更多
关键词 Metallic Reserves of submarine manganese Nodules to be Estimated and Harnessed Prudently Evidence from China’s Jiaolong manned submersible
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Assessment of self- and cross-absorbed SAF values for HDRK-man using GEANT4 code: internal photon and electron emitters
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作者 Maroua Bhar Omrane Kadri Kais Manai 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第10期40-47,共8页
The ultimate need to account for the partial amount of energy deposited in target tissue/organ resulting from internal inhalation,ingestion,and injection intakes of radionuclides,defined by the Medical Internal Radiat... The ultimate need to account for the partial amount of energy deposited in target tissue/organ resulting from internal inhalation,ingestion,and injection intakes of radionuclides,defined by the Medical Internal Radiation Dosimetry committee as the specific absorbed fraction(SAF),has become obvious.In this study,we assessed the SAF values for self-and cross-absorption,which were calculated for a uniform distribution of monoenergetic photon and electron emitters with energies ranging from 15 keV to 3 MeV.The voxelized human phantom‘‘High-Definition Reference Korean-man’’(HDRK-man),which was implemented using the Monte Carlo simulation code GEANT4(version 10.1),was used for several combinations of target–source organs.The results were compared to those of the International Commission on Radiological Protection Reference(ICRP133)and Zubal phantoms.It was found that the SAF values of the three models have a similar trend.However,the SAF values for the HDRK-man phantom were higher than those of the other two models,with a relatively good agreement with those for the ICRP133 phantom(differences of 13.9±2.8 and 12.1±3.2 for photon and electron emitters,respectively).To analyze the differences in SAF values,we calculated the chord length distributions(CLDs)for selected target–source combinations.The parameters of organ mass(or volume)and CLDs,in addition to the adopted computational procedures,mainly cause such discrepancies.For realistic radionuclide emission spectra,an overall overestimation was observed when computing the S values for three radiopharmaceuticals studied(I-131,In-111,and Lu-177)and for liver–spleen intra-and inter-organ absorption when compared with published data.The new arrangement of S and SAF values is expected to add value for multidisciplinary research and clinical communities. 展开更多
关键词 GEANT4 Monte Carlo simulation INTERNAL DOsIMETRY HDRK-man s and sAF VALUEs
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A Comment on Frank O'Connor's Short Story "The Man of the House
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《淮南师范学院学报》 1997年第2期85-86,共2页
This is moving story of a boy's growing up and of the deep love between Mother and
关键词 man A Comment on Frank O’Connor’s short story The man of the House
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Man’s Best Friend——Dog
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作者 李家峰 《中学英语园地(初一版)》 2007年第Z1期61-61,共1页
在西方,人们通常将狗作为宠物来养,有些家庭养狗用以防盗。在牧羊区,人们则用牧羊犬来帮助牧民管理羊群。因此dog被称为人类最好的朋友(man’s best friend)。
关键词 man 牧羊犬 DOG s Best Friend
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One Man’s Charity Pursuit
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作者 FAN GUOZHEN 《The Journal of Human Rights》 2011年第6期19-20,共2页
When Lou Zongquan became a millionaire and thought his money was more than enough to sustain a kungfu school over 10 years ago, the engineer-turned-businessman decided it was time to feed his martial ambition. In less... When Lou Zongquan became a millionaire and thought his money was more than enough to sustain a kungfu school over 10 years ago, the engineer-turned-businessman decided it was time to feed his martial ambition. In less than a year, however, the kungfu fan found that his dream would lead him to running an orphanage. 展开更多
关键词 One man s Charity Pursuit THAN
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Waterfalls Found In No-Man's Riverbed Area
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《China's Tibet》 1999年第2期36-37,共2页
关键词 man Waterfalls Found In No-mans Riverbed Area In
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One Man's Fight Against Coronary Heart Disease
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《China Today》 1994年第1期62-63,共2页
Zhao Guoxin has the future all mapped out.First,he intends to turn the center into a full-time industry as a Sino-foreign joint venture com-plete with two pharmaceutical plants and a 200-bed hospital for coronary hear... Zhao Guoxin has the future all mapped out.First,he intends to turn the center into a full-time industry as a Sino-foreign joint venture com-plete with two pharmaceutical plants and a 200-bed hospital for coronary heart patients.This,he thinks,should take about three years. 展开更多
关键词 man One mans Fight Against Coronary Heart Disease
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Wei Zhihe and Tian'anmen Square──A man's life and Tian'anmen Square are intricately connected
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作者 By staff reporter ZHANG HUA 《China Today》 1999年第10期55-57,共3页
关键词 A mans life and Tian’anmen square are intricately connected Wei Zhihe and Tian’anmen square
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Gyila:Tibet's First Senior Weather Man
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作者 WANGYUANHONG 《China's Tibet》 2002年第5期36-37,共2页
There is no-one in the field of weather broadcasting in Tibet who does notknow about Gyila: Top 10 Youth of China, China’s Outstanding Scientist, winner of the 5th China Youth Scientific Progress, and winner of first... There is no-one in the field of weather broadcasting in Tibet who does notknow about Gyila: Top 10 Youth of China, China’s Outstanding Scientist, winner of the 5th China Youth Scientific Progress, and winner of first May 4th Medal for Tibetan Youths.What people tell of him are legendary stories. Actually, he is an ordinary man who has cut a brilliant figure in work. 展开更多
关键词 Gyila:Tibet’s First senior Weather man In ICI
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