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储层预测的地震属性优选技术研究 被引量:74
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作者 鲍祥生 尹成 +2 位作者 赵伟 张金淼 刘志斌 《石油物探》 EI CSCD 2006年第1期28-33,共6页
地震属性分析的关键是地震属性的优选问题。目前主要用来优选属性的方法有4种,即①专家经验法;②数学理论法;③专家经验与数学理论结合法;④正演模拟确定法。其中,数学理论法具有灵活性强、工作量低、效率较高等优点,是目前进行属性... 地震属性分析的关键是地震属性的优选问题。目前主要用来优选属性的方法有4种,即①专家经验法;②数学理论法;③专家经验与数学理论结合法;④正演模拟确定法。其中,数学理论法具有灵活性强、工作量低、效率较高等优点,是目前进行属性优选的主流方法。在此基础上,提出了一种基于数学理论的地震属性优选方法。该属性优选方法的基本原理是:首先选择有效性大的属性;然后选择符合率大的属性,并对有效性大的属性和符合率大的属性进行交集运算,获得灵敏属性;最后对灵敏属性进行压缩处理,得到用来进行储层预测的属性。给出了各类属性的选择方法和原则,并用检验井对预测效果进行了误差分析。将该方法应用于绥中36-1油田某一储层的含油气性预测,并与单纯利用有效性或符合率的预测结果进行了对比。对比结果和检验井验证结果均表明,该方法的预测效果好,预测结果与实际情况吻合率高。 展开更多
关键词 地震属性分析 地震属性的优选 有效性 符合率 压缩处理
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95个猪场大肠杆菌耐药表型及氨基糖苷类药物耐药基因型调查 被引量:65
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作者 汤景元 王红宁 +2 位作者 张鹏举 冮婷婷 曾博 《畜牧兽医学报》 CAS CSCD 北大核心 2008年第4期472-477,共6页
为调查我国规模化猪场大肠杆菌细菌耐药性及其氨基糖苷类药物耐药基因的流行状况,采用K-B(Kir-by-Bauer)法检测2006-2007年从四川、重庆、湖北等19个省95个规模化猪场分离的480株大肠杆菌对19种抗生素的耐药性。结果表明:仅有多黏菌素B(... 为调查我国规模化猪场大肠杆菌细菌耐药性及其氨基糖苷类药物耐药基因的流行状况,采用K-B(Kir-by-Bauer)法检测2006-2007年从四川、重庆、湖北等19个省95个规模化猪场分离的480株大肠杆菌对19种抗生素的耐药性。结果表明:仅有多黏菌素B(85.6%)、头孢噻肟(85.3%)、阿米卡星(84.8%)和大观霉素(65.0%)相对敏感。480株大肠杆菌以多重耐药菌株为主,其中13、14、15、16和17重耐药较多,并且有26株18重耐药,14株19重耐药。采用WHONET5.4软件分析大肠杆菌耐药性,对阿米卡星、头孢噻肟和多黏菌素B耐药的猪场相对较少,分别是29、26和24个。采用PCR方法检测氨基糖苷类相关耐药基因,耐药基因检出率分别是aadA1(65.89%)、aaC2(52.35%)、aaC4(12.91%)和aphA3(10.95%)。耐药基因型检出率较高的是aadA1/aaC2(29.61%)、aadA1(18.04%)。Excel软件统计相关耐药基因的猪场分布,表明耐药基因型aadA1/aaC2(43)、aa-dA1/aaC2/aaC4(20)和aadA1/aaC2/aaC4/aphA3(20)在猪场分布较普遍。耐药基因和耐药性比较表明大肠杆菌对氨基糖苷类药物耐药表型与耐药基因型符合率较高的是阿米卡星(68.39%)。本研究表明猪肠道内常在大肠杆菌菌群不仅产生较高的多重耐药性,也成为耐药基因的储存库,对猪场环境中耐药基因在致病菌和非致病菌间传播发挥重要作用,能够作为检测细菌耐药性的指示菌。 展开更多
关键词 大肠杆菌 耐药表型 耐药基因型 符合率
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合同责任与侵权责任竞合问题研究 被引量:23
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作者 汪世虎 《现代法学》 CSSCI 北大核心 2002年第4期109-115,共7页
合同责任与侵权责任竞合是司法实践中常见的法律现象 ,理论上存在不同的学说。本文通过对民事责任竞合的各种理论及法律对策的分析 ,认为责任竞合就是请求权竞合 ,责任竞合时 ,权利人可选择请求权 ,但只能实现一项。同时 ,针对我国《合... 合同责任与侵权责任竞合是司法实践中常见的法律现象 ,理论上存在不同的学说。本文通过对民事责任竞合的各种理论及法律对策的分析 ,认为责任竞合就是请求权竞合 ,责任竞合时 ,权利人可选择请求权 ,但只能实现一项。同时 ,针对我国《合同法》的规定 ,提出了完善的意见。 展开更多
关键词 民事责任竞合 合同责任 侵权责任 竞合问题 法律现象 请求权竞合 选择请求权 理论 中国 意见
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非紧超凸度量空间中的Browder不动点定理及其对重合问题的应用 被引量:47
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作者 文开庭 《数学进展》 CSCD 北大核心 2005年第2期208-212,共5页
在非紧超凸度量空间中的非紧允许集上,建立了一个新的Browder不动点定理.作为应用,在非紧超凸度量空间中,研究了KyFan截口问题和相交问题,并新建了两个KyFan重合定理.
关键词 超凸度量空间 BROWDER不动点定理 允许集 非紧性测度 截口 相交 重合
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On the Existence of Positive Periodic Solutions for Neutral Functional Differential Equation with Multiple Deviating Arguments 被引量:36
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作者 Shi-pingLu Wei-gaoGe 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2003年第4期631-640,共10页
By means of an abstract continuation theory for k-set contraction and continuation theorem of coincidence degree principle, some criteria are established for the existence of positive periodic solutions of following n... By means of an abstract continuation theory for k-set contraction and continuation theorem of coincidence degree principle, some criteria are established for the existence of positive periodic solutions of following neutral functional differential equation 展开更多
关键词 Positive periodic solution k-set contraction coincidence degree neutral functional differential equation
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论侵权法上因果关系与过错的竞合及其解决路径 被引量:37
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作者 李中原 《法律科学(西北政法大学学报)》 CSSCI 北大核心 2013年第6期91-105,共15页
因果关系与过错的竞合是现代侵权法上因果关系理论向主观领域扩张的结果,二者竞合的实质主要在于"可预见性"在因果关系和过错中的理论安排,当代欧美侵权法在此呈现出两种模式。"相当性"与"可预见性"之间... 因果关系与过错的竞合是现代侵权法上因果关系理论向主观领域扩张的结果,二者竞合的实质主要在于"可预见性"在因果关系和过错中的理论安排,当代欧美侵权法在此呈现出两种模式。"相当性"与"可预见性"之间在因果关系层面的相互替代性是德国模式的合理基础所在,但是,德国模式却极易导致适用上的混淆或误解。在二者竞合问题的解决路径中,以过错的"可预见性"替代因果关系的"相当性"是最合理的方案。根据"相当性"或"客观可预见性"回归过错的基本思路,必须建构和强化过错的二元结构和"法律上的可预见性"理论。 展开更多
关键词 因果关系 过错 竞合 可预见性
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综合物探方法在湖北大冶鸡冠咀铜金矿深部及外围找矿中的应用 被引量:29
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作者 邰文星 金尚刚 +2 位作者 何彦南 杨梅珍 刘万龙 《地质与勘探》 CAS CSCD 北大核心 2019年第4期1010-1025,共16页
以湖北大冶鸡冠咀铜金矿床深部及其外围找矿预测为目标,在深入认识鸡冠咀铜金矿床地质特征的基础上,对研究区重力、磁测、电法测量资料进行精细反演,研究含矿地质体与物探异常的对应关系,获取矿区深部和外围物探异常信息。研究证实研究... 以湖北大冶鸡冠咀铜金矿床深部及其外围找矿预测为目标,在深入认识鸡冠咀铜金矿床地质特征的基础上,对研究区重力、磁测、电法测量资料进行精细反演,研究含矿地质体与物探异常的对应关系,获取矿区深部和外围物探异常信息。研究证实研究区岩矿石物性差异明显、与矿有关的地质体与重磁异常具有良好的吻合性,研究区内断裂接触带、大理岩俘虏体、隐伏岩体表现出重磁同高、重磁异常梯度带等特征,是寻找深部盲矿体的有利部位。总结了5种地球物理找矿标志,构建了“一个主要目标,两种分析,三种方法,五个找矿标志”的矽卡岩型铜金矿床的地球物理找矿模式,对鸡冠咀矿区深部及外围进行靶区优选,指导鄂东南矿集区矿产勘查工作,具有良好的示范作用。 展开更多
关键词 鸡冠咀铜金矿床 物探异常 找矿预测 吻合性 大冶 湖北
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Existence of at Least Two Periodic Solutions of a Ratio-dependent Predator-prey Model with Exploited Term 被引量:23
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作者 De-sheng Tian Xian-wu Zeng 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2005年第3期489-494,共6页
In this paper, we study a non-autonomous ratio-dependent predator-prey model with exploited term. By means of the coincidence degree theory, we establish a sufficient condition for the existence of at least two positi... In this paper, we study a non-autonomous ratio-dependent predator-prey model with exploited term. By means of the coincidence degree theory, we establish a sufficient condition for the existence of at least two positive periodic solutions of this model. 展开更多
关键词 Predator-prey model RATIO-DEPENDENT exploited term periodic solution coincidence degree
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一个新的Ky Fan匹配定理及其在L-凸度量空间中的应用(英文) 被引量:22
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作者 文开庭 《应用泛函分析学报》 CSCD 2008年第4期305-312,共8页
建立了转移开覆盖的一个新的Ky Fan型匹配定理.作为应用,获得了Fan—Browder重合定理,不动点定理、极大元定理,相交定理和截口定理.
关键词 L-凸度量空间 非紧性测度 转移开(闭) 匹配 不动点 重合 相交 截口
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高职专业设置与区域经济社会发展吻合度研究——以南通地区高职院校专业设置为例 被引量:20
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作者 陈旭东 樊登柱 《职业技术教育》 北大核心 2012年第29期10-14,共5页
以南通地区的经济发展现状与产业结构发展趋势为依据,分析南通高职院校专业设置与区域经济社会和地区支柱产业的匹配情况。在此基础上,提出以区域需求为依据,打造品牌专业群;以沿海发展战略需求为依据,建设骨干专业;以新兴产业建设为依... 以南通地区的经济发展现状与产业结构发展趋势为依据,分析南通高职院校专业设置与区域经济社会和地区支柱产业的匹配情况。在此基础上,提出以区域需求为依据,打造品牌专业群;以沿海发展战略需求为依据,建设骨干专业;以新兴产业建设为依据,培育新专业;以加强校企合作为契机,优化专业设置等发展策略。 展开更多
关键词 南通 高职院校 专业设置 区域经济 吻合度
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EXISTENCE AND GLOBAL ATTRACTIVITY OF POSITIVE PERIODIC SOLUTION OF A LOGISTIC GROWTH SYSTEM WITH FEEDBACK CONTROL AND DEVIATING ARGUMENTS 被引量:17
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作者 杨帆 蒋达清 《Annals of Differential Equations》 2001年第4期377-384,共8页
In this paper, we study the existence and global attractivity of positive peri- odic solutions of a Logistic growth system with feedback control and deviating arguments. A sufficient condition is derived for the exist... In this paper, we study the existence and global attractivity of positive peri- odic solutions of a Logistic growth system with feedback control and deviating arguments. A sufficient condition is derived for the existence of a unique peri- odic solution with strictly positive components which is globally asymptotically stable by using the method of coincidence degree and Liapunov functional. Some new results are obtained. The known results are improved and generalized. 展开更多
关键词 positive periodic solution Logistic growth system feedback con-trol global attractivity coincidence degree
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Periodicity and Stability in Periodic n-Species Lotka-Volterra Competition System with Feedback Controls and Deviating Arguments 被引量:17
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作者 MengFAN KeWANG +1 位作者 PatriciaJ.Y.WONG RaviP.AGARWAL 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第4期801-822,共22页
By using the method of coincidence degree and Lyapunov functional, a set ofeasily applicable criteria are established for the global existence and global asymptotic stabilityof strictly positive (componentwise) period... By using the method of coincidence degree and Lyapunov functional, a set ofeasily applicable criteria are established for the global existence and global asymptotic stabilityof strictly positive (componentwise) periodic solution of a periodic n-species Lotka-Volterracompetition system with feedback controls and several deviating arguments. The problem considered inthis paper is in many aspects more general and incorporate as special cases various problems whichhave been studied extensively in the literature. Moreover, our new criteria, which improve andgeneralize some well known results, can be easily checked. 展开更多
关键词 strictly positive periodic solutions globally asymptotic stability Lotka-Volterra competition system feedback controls deviating arguments coincidence degree Lyapunov functional
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Quantum efficiency calibration of opto-electronic detector by means of correlated photons method 被引量:16
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作者 李健军 郑小兵 +2 位作者 卢云君 邹鹏 张伟 《Chinese Optics Letters》 SCIE EI CAS CSCD 2008年第7期472-475,共4页
A new calibration method of detectors can be realized by using correlated photons generated in spontaneous parametric down-conversion (SPDC) effect of nonlinear crystal. An absolute calibration system of detector qu... A new calibration method of detectors can be realized by using correlated photons generated in spontaneous parametric down-conversion (SPDC) effect of nonlinear crystal. An absolute calibration system of detector quantum efficiency is performed. And its principle and experimental setup are introduced. A continuouswave (CW) ultraviolet (351 nm), diode-pumped, frequency-doubled, and solid-state laser is used to pump BBO crystal. The quantum efficiencies of the photomultiplier at 633, 702, and 789 nm are measured respectively. The coincidence peaks are observed using coincidence circuit. Some measurement factors including the filter bandwidth of trigger channel, the detector position alignment and polarization of the pump light are analyzed. The uncertainties of this calibration method are also analyzed, and the relative uncertainties of total calibration are less than 5.8%. The accuracy of this method could be improved in the future. 展开更多
关键词 CALIBRATION coincidence circuits Computer networks Detectors Electromagnetic waves LASERS Light Optical frequency conversion PHOTONS POWDERS PUMPS Semiconductor quantum dots STEREOCHEMISTRY Uncertainty analysis
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A KY FAN MATCHING THEOREM FOR TRANSFER COMPACTLY OPEN COVERS AND THE APPLICATION TO THE FIXED POINT 被引量:18
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作者 文开庭 《数学物理学报(A辑)》 CSCD 北大核心 2006年第B12期1159-1165,共7页
In this article, a Ky Fan matching theorem for transfer compactly open covers is established. As applications, a Fan-Browder coincidence theorem, a Ky Fan best approximation theorem and a Brouwer-Schauder-Rothe type f... In this article, a Ky Fan matching theorem for transfer compactly open covers is established. As applications, a Fan-Browder coincidence theorem, a Ky Fan best approximation theorem and a Brouwer-Schauder-Rothe type fixed point theorem are obtained. 展开更多
关键词 超凸度量空间 最优逼近 固定点 匹配定理
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有限度量紧开值集值映射的R-KKM定理及其对不动点的应用 被引量:18
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作者 文开庭 李和睿 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第10期110-112,共3页
在非紧FC-度量空间中建立了有限度量紧开值集值映射的R-KKM定理.作为应用,获得了非紧FC-度量空间中有限度量紧开(闭)值集值映射的匹配定理、重合定理和不动点定理.
关键词 FC-度量空间 R-KKM映射 匹配 重合 不动点
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New Unique Common Fixed Point Results for Four Mappings with Ф-Contractive Type in 2-Metric Spaces 被引量:14
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作者 Yongjie Piao Yuanfeng Jin 《Applied Mathematics》 2012年第7期734-737,共4页
In this paper, some new unique common fixed points for four mappings satisfying Ф-contractive conditions on non-complete 2-metric spaces are obtained, in which the mappings do not satisfy continuity and commutation. ... In this paper, some new unique common fixed points for four mappings satisfying Ф-contractive conditions on non-complete 2-metric spaces are obtained, in which the mappings do not satisfy continuity and commutation. The main results generalize and improve many well-known and corresponding conclusions in the literatures. 展开更多
关键词 2-Metric Space Class Ф CAUCHY Sequence coincidence POINT UNIQUE Common Fixed POINT
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TABULAR TECHNIQUES FOR OR-COINCIDENCE LOGIC 被引量:12
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作者 Wang Pengjun Chen Xiexiong 《Journal of Electronics(China)》 2006年第2期269-273,共5页
The map folding method for the conversion between Boolean expression and COC expansions is analyzed. Based on it, the tabular techniques are proposed for the conversion between Boolean expression and COC expansion and... The map folding method for the conversion between Boolean expression and COC expansions is analyzed. Based on it, the tabular techniques are proposed for the conversion between Boolean expression and COC expansion and for the derivation of GOC expansions with fixed polarities. The Fast Tabular Technique (FTT) for the conversion from the Boolean expression to the GOC expansion with the required polarity is also proposed. The simulative result shows this FTT is faster than others in references because of its inherent parallelism. 展开更多
关键词 Tabular technique OR-coincidence logic Fixed polarity OR-coincidence expansion
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A super-high resolution frequency standard measuring approach based on phase coincidence characteristics between signals 被引量:13
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作者 李智奇 周渭 +1 位作者 陈发喜 刘晨光 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期287-290,共4页
A method for super high resolution comparison measurement is proposed in this paper with a comparison between the frequency standards of different nominal frequencies, which is based on phase coincidence detection of ... A method for super high resolution comparison measurement is proposed in this paper with a comparison between the frequency standards of different nominal frequencies, which is based on phase coincidence detection of the two compared signals. It utilizes the regular phase shift characteristics between the signals. The resolution of the measurement approach can reach 10^-13/s at 5 MHz, and the self-calibration resolution can achieve 10^-14/s in the comparison between 10 MHz and 100 MHz, or even can reach 10^-15/s in the comparison between 10 MHz and 190 MHz. This method implies significant progress in the development of the high precision frequency standard comparison technology. 展开更多
关键词 frequency measurement RESOLUTION phase coincidence equivalent phase comparison frequency
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KKM TYPE THEOREMS AND COINCIDENCE THEOREMS ON L-CONVEX SPACES 被引量:13
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期419-426,共8页
Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixe... Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixed point theorems are obtained in L-convex spaces. These theorems improve and generalize many important known results in recent literature. 展开更多
关键词 KKM type theorem coincidence theorem L-convex space
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转移紧开覆盖的新的Ky Fan匹配定理及其对极大元的应用(英文) 被引量:14
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作者 文开庭 《数学进展》 CSCD 北大核心 2009年第3期295-301,共7页
建立了转移紧开覆盖的两个新的Ky Fan匹配定理.作为应用,获得了新的Fan-Browder重合定理、不动点定理和极大元定理.
关键词 L-凸空间 匹配 转移紧开(闭) 重合 极大元
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