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Semigroup of Weakly Continuous Operators Associated to a Generalized Schrödinger Equation
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作者 Yolanda Silvia Santiago Ayala 《Journal of Applied Mathematics and Physics》 2023年第4期1061-1076,共16页
In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously r... In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously respect to the initial data in P’. Introducing a family of weakly continuous operators, we prove that this family is a semigroup of operators in P’. Then, with this family of operators, we get a fine version of the existence and dependency continuous theorem obtained. Finally, we provide some consequences of this study. 展开更多
关键词 semigroups Theory weakly Continuous Operators Existence of Solution Generalized Schrödinger Equation Distributional Problem Periodic Distributional Space
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P-kernel Normal Systems in Weakly P-inversive Semigroups 被引量:1
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作者 CHEN Qian-hua FAN Xing-kui 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期171-177,共7页
In this paper, we first give the concept of weakly P-inversive semigroup S(P). Then we describe the strong P-congruences on S(P) in terms of their P-kernel normal systems. It is proved that there is a bijection be... In this paper, we first give the concept of weakly P-inversive semigroup S(P). Then we describe the strong P-congruences on S(P) in terms of their P-kernel normal systems. It is proved that there is a bijection between the strong P-congruences and the P-kernel normal systems. Finally, it is also prove that the lattice of strong P-congruences and the lattice of P-kernel normal systems on S(P) are isomorphic. 展开更多
关键词 weakly P-inversive semigroup strong P-congruence P-kernel normal system lattice isomorphism
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Some Characterizations of Left Weakly Regular Ordered Semigroups 被引量:1
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作者 TANG JIAN XIE XIANG-YUN 《Communications in Mathematical Research》 CSCD 2011年第3期253-267,共15页
In this paper, the notion of left weakly regular ordered semigroups is introduced. Furthermore, left weakly regular ordered semigroups are characterized by the properties of their left ideals, right ideals and (gener... In this paper, the notion of left weakly regular ordered semigroups is introduced. Furthermore, left weakly regular ordered semigroups are characterized by the properties of their left ideals, right ideals and (generalized) bi-ideals, and also by the properties of their fuzzy left ideals, fuzzy right ideals and fuzzy (generalized) bi-ideals. 展开更多
关键词 left weakly regular ordered semigroup generalized bi-ideal fuzzy left ideal fuzzy right ideal fuzzy bi-ideal fuzzy generalized bi-ideal
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A New Method Based on Evolutionary Algorithm for Symbolic Network Weak Unbalance
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作者 Yirong Jiang Weijin Jiang +4 位作者 Jiahui Chen Yang Wang Yuhui Xu Lina Tan Liang Guo 《Journal on Internet of Things》 2019年第2期41-53,共13页
The symbolic network adds the emotional information of the relationship,that is,the“+”and“-”information of the edge,which greatly enhances the modeling ability and has wide application in many fields.Weak unbalanc... The symbolic network adds the emotional information of the relationship,that is,the“+”and“-”information of the edge,which greatly enhances the modeling ability and has wide application in many fields.Weak unbalance is an important indicator to measure the network tension.This paper starts from the weak structural equilibrium theorem,and integrates the work of predecessors,and proposes the weak unbalanced algorithm EAWSB based on evolutionary algorithm.Experiments on the large symbolic networks Epinions,Slashdot and WikiElections show the effectiveness and efficiency of the proposed method.In EAWSB,this paper proposes a compression-based indirect representation method,which effectively reduces the size of the genotype space,thus making the algorithm search more complete and easier to get better solutions. 展开更多
关键词 weak structural balance signed networks evolutionary algorithms incremental computation compressed representation
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两类特殊的双扭曲积埃尔米特流形
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作者 张辉 卢晓英 +1 位作者 何勇 韩江慧 《新疆师范大学学报(自然科学版)》 2024年第2期26-31,51,共7页
设(M_(1),g)和(M_(2),h)是两个埃尔米特流形,双扭曲积埃尔米特流形(f_(2)M_(1)×f_(1)M_(2),G)是赋予了扭曲积埃尔米特度量G=f_(2)^(2)g+f_(1)^(2)h的乘积流形M_(1)×M_(2),其中f_(1)和f_(2)分别是M_(1)和M_(2)上的正值光滑函... 设(M_(1),g)和(M_(2),h)是两个埃尔米特流形,双扭曲积埃尔米特流形(f_(2)M_(1)×f_(1)M_(2),G)是赋予了扭曲积埃尔米特度量G=f_(2)^(2)g+f_(1)^(2)h的乘积流形M_(1)×M_(2),其中f_(1)和f_(2)分别是M_(1)和M_(2)上的正值光滑函数。文章给出双扭曲积埃尔米特流形的挠率表达式,得到双扭曲积埃尔米特流形是凯勒流形或平衡流形的充要条件,并在特定条件下给出双扭曲积埃尔米特流形满足弱爱因斯坦条件的充要条件。 展开更多
关键词 埃尔米特流形 双扭曲积 平衡流形 弱爱因斯坦条件
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不同运动干预方式改善衰弱老年人平衡功能的网状Meta分析
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作者 严晓晨 陈玲 +3 位作者 何元元 覃帆 张燎芝 曾掩 《老年医学研究》 2024年第1期7-12,共6页
目的采用网状Meta评价不同运动干预对老年衰弱患者平衡能力的影响。方法检索PubMed、Embase、Web of Science、The Cochrane Library及中国生物医学文献数据库、中国知网、万方、维普数据库中关于运动训练对衰弱老年人平衡功能影响的随... 目的采用网状Meta评价不同运动干预对老年衰弱患者平衡能力的影响。方法检索PubMed、Embase、Web of Science、The Cochrane Library及中国生物医学文献数据库、中国知网、万方、维普数据库中关于运动训练对衰弱老年人平衡功能影响的随机对照试验。检索期限为建库至2023年9月。由2名研究者独立进行文献筛选、提取及质量评价。采用Stata 14.0软件对Berg平衡量表(BBS)、简易体能状况量表(SPPB)、“站立行走”计时试验(TUG)、6 min步行试验(6MWT)四个平衡功能相关指标得分进行网状Meta分析。结果共纳入15项随机对照试验。网状Meta分析结果显示,在提高BBS评分上核心运动效果最佳,在提高SPPB评分上抗阻运动最佳,在提高TUG时间上核心运动最佳,在提高6MWT距离中平衡训练效果最佳。结论9种运动方式均能改善衰弱老年人平衡功能,其中核心运动、抗阻运动、多元运动、平衡训练效果最佳。 展开更多
关键词 衰弱 老年人 运动 干预 平衡功能 网状Meta分析
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富水软弱地层常压开仓综合施工技术
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作者 关丽娟 陈思捷 +1 位作者 李昕 黄钰超 《广州建筑》 2024年第6期54-59,共6页
本文依托广州市某轨道交通工程,为避免双仓式泥水盾构在富水软弱地层盾构掘进作业中出现堵管、堵仓现象和影响掌子面稳定的不理想现象,提出针对富水软弱地层条件下盾构掘进常压开仓的新施工技术。该技术通过对加固及开仓位置地质分析与... 本文依托广州市某轨道交通工程,为避免双仓式泥水盾构在富水软弱地层盾构掘进作业中出现堵管、堵仓现象和影响掌子面稳定的不理想现象,提出针对富水软弱地层条件下盾构掘进常压开仓的新施工技术。该技术通过对加固及开仓位置地质分析与泥水平衡的压力控制,采用惰性注浆+丙烯酸盐化学注浆双重加固,实时控制注浆压力、配方、粘度以及混合比,分析地面沉降数据,通过抽芯取样等方式检测浆液的稳定性和可挖性,增强其支护性能以保证人员安全开仓换刀,加装新型搅拌棒,充分搅拌处理堆渣堆积的问题。研究表明:(1)新技术可使掌子面更为稳定,地面沉降值与速率远优于传统做法;(2)形成了新的高强度骨架网格固结体,提高土体加固、砂层堵水性能及稳定作用,保障开仓过程中的安全稳定;(3)新型搅拌棒可极大解决浮渣漂浮导致的堵管堵仓现象,研究成果可为盾构富水砂层提供有效的施工指导。 展开更多
关键词 富水软弱地层 泥水平衡 惰性注浆 丙烯酸盐地面注浆 搅拌棒
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超高比例新能源弱电网系统供电关键问题研究
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作者 刘泽洪 周原冰 +2 位作者 李隽 燕志宇 郑炜 《新型电力系统》 2024年第3期282-296,共15页
随着电力系统中新能源并网规模快速增加,系统形态特征与运行机理发生深刻变化,特别对远离主网、缺乏传统能源的地区,面临电力保供和系统安全稳定等严峻挑战。现有研究多从源网荷储某一环节切入,提出中高比例新能源电力系统供电可靠性提... 随着电力系统中新能源并网规模快速增加,系统形态特征与运行机理发生深刻变化,特别对远离主网、缺乏传统能源的地区,面临电力保供和系统安全稳定等严峻挑战。现有研究多从源网荷储某一环节切入,提出中高比例新能源电力系统供电可靠性提升方法,缺乏对超高比例新能源弱电网系统特有难题的针对性考虑及系统性、前瞻性解决方案。为此,文中以新能源电量占比超过80%、新能源并网点短路比低于1.5的弱电网系统为研究对象,提出含电源及灵活调节资源优化配置、电网组网模式、暂态稳定运行分析的总体研究框架,并以我国西部某超高比例新能源弱电网系统为例开展实证研究。研究成果表明,所提方案以超高比例新能源发电为基础,以弱联电网为载体,以多元储能及负荷柔性调节为灵活性支撑,以构网控制技术为安全支撑,能有效保障系统可靠供电,为未来超高比例新能源新型电力系统的构建提供借鉴参考。 展开更多
关键词 超高比例新能源 弱电网 电力电量平衡 暂态建模仿真 多元储能 构网控制
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Evaluation and extraction of weak gravity and magnetic anomalies 被引量:2
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作者 刘云祥 《Applied Geophysics》 SCIE CSCD 2007年第4期288-293,共6页
In this paper, I introduce what are called weak gravity and magnetic anomalies and propose standards for estimating their reliability. I also introduce new techniques for processing this kind of weak anomaly. These te... In this paper, I introduce what are called weak gravity and magnetic anomalies and propose standards for estimating their reliability. I also introduce new techniques for processing this kind of weak anomaly. These techniques consist of interference elimination and weak signal extraction. Practical applications have proved their effectiveness, Weak gravity and magnetic anomalies will get more attention with the development of targeted exploration. 展开更多
关键词 gravity and magnetic exploration weak anomaly anomaly extraction less balance filtering distortion correction
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Weak signal extraction of micro-motor rotor unbalance based on all-phase fast Fourier transform
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作者 Qinghua Liu Xingxing Xu +2 位作者 Zhenrong Lu Liwei Yu Dong Jiang 《International Journal of Mechanical System Dynamics》 EI 2024年第2期202-212,共11页
To improve the dynamic balancing accuracy of the micro-motor rotor,an unbalanced vibration feature extraction based on an all-phase fast Fourier transform(APFFT)method is proposed.The amplitude and phase of the signal... To improve the dynamic balancing accuracy of the micro-motor rotor,an unbalanced vibration feature extraction based on an all-phase fast Fourier transform(APFFT)method is proposed.The amplitude and phase of the signal are extracted by spectrum analysis after windowing the unbalanced signal.The mathematical model is derived to simulate the weak signal of rotor unbalance.The simulation results show that this method is accurate in extracting the weak signal of the rotor under different noise levels.The micro-motor rotor unbalanced test system is developed for experimental validations.The accuracy and stability of the vibration amplitude and phase extracted by the APFFT are better than the accuracy and stability from the hardware filtering method.The rotor unbalance is reduced by more than 80%.Furthermore,secondary balance of the rotor after the first balance is carried out.The proposed method can still extract the residual unbalance of the rotor.The results demonstrated that the proposed method can achieve a reduction rate of 90%and the accuracy is within 5mg,verifying the effectiveness of the proposed method for high-precision rotor dynamic balance. 展开更多
关键词 all-phase fast Fourier transform feature extraction rotor dynamic balance weak signal
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On Congruences Induced by Certain Relations on “Semigroups”
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作者 K. V. R. Srinivas 《Advances in Pure Mathematics》 2015年第9期579-582,共4页
In his paper “On quasi-separative ‘semigroup’s’”, Krasilnikova, Yu. I. and Novikov, B. V. have studied congruences induced by certain relations on a “semigroup”. They further showed that if the “semigroup” is... In his paper “On quasi-separative ‘semigroup’s’”, Krasilnikova, Yu. I. and Novikov, B. V. have studied congruences induced by certain relations on a “semigroup”. They further showed that if the “semigroup” is quasi separative then the induced congruence is a semilattice congruence. In this paper we continue the study of these relations and the induced congruences i.e., the congruences induced by certain relations on ‘‘semigroup’s”. In this paper mainly it is observed that if S is a quasi-separative and regular “semigroup” then the necessary and sufficient condition for to be the smallest semilattice congruence η is obtained. 展开更多
关键词 Cancellative “semigroup Quasi-Separative ''semigroup’s” weakly Cancellative ''semigroup’s” weakly balanced “semigroup
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WEAK REGULARIZATION FOR A CLASS OF ILL-POSED CAUCHY PROBLEMS
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作者 黄永忠 郑权 《Acta Mathematica Scientia》 SCIE CSCD 2006年第3期483-490,共8页
This article is concerned with the ill-posed Cauchy problem associated with a densely defined linear operator A in a Banach space. A family of weak regularizing operators is introduced. If the spectrum of A is contain... This article is concerned with the ill-posed Cauchy problem associated with a densely defined linear operator A in a Banach space. A family of weak regularizing operators is introduced. If the spectrum of A is contained in a sector of right-half complex plane and its resolvent is polynomially bounded, the weak regularization for such ill-posed Cauchy problem can be shown by using the quasi-reversibilky method and regularized semigroups. Finally, an example is given. 展开更多
关键词 Ill-posed Cauchy problem QUASI-REVERSIBILITY family of weakly regularizing operators fractional power regularized semigroup
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深浅耦合注浆技术在松散破碎围岩中的研究与应用 被引量:1
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作者 吴方超 《山西化工》 2023年第1期149-151,共3页
针对章村矿松散破碎围岩巷道支护问题日益突出,若采用不适当的支护措施,将会造成巷道围岩变形愈加剧烈,最终导致巷道变形破坏的问题。分析了章村矿-200井底车场的变形破坏特片,提出针对性耦合注浆技术方案。实际应用效果表明,该方案支... 针对章村矿松散破碎围岩巷道支护问题日益突出,若采用不适当的支护措施,将会造成巷道围岩变形愈加剧烈,最终导致巷道变形破坏的问题。分析了章村矿-200井底车场的变形破坏特片,提出针对性耦合注浆技术方案。实际应用效果表明,该方案支护效果良好,有效提高了巷道支护结构强度,取得显著应用成效。 展开更多
关键词 压力显现 应力平衡 耦合注浆 弱面控制
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基于光学偏振控制的散粒噪声极限微振动光学测量方法
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作者 伍凯凯 谢博娅 +3 位作者 陈琳 游淞清 熊哲文 杨鹏 《红外与激光工程》 EI CSCD 北大核心 2023年第7期233-242,共10页
物体微振动信号测量在磁场、建筑、生物成像及航空航天等方面具有重要的应用价值。但是,物体微振动产生的弱反射光不仅极其微弱,易受到探测距离、雨雾气等环境因素的干扰,而且低频振动的振动形式多变,易受到经典噪声影响,难以实现极端... 物体微振动信号测量在磁场、建筑、生物成像及航空航天等方面具有重要的应用价值。但是,物体微振动产生的弱反射光不仅极其微弱,易受到探测距离、雨雾气等环境因素的干扰,而且低频振动的振动形式多变,易受到经典噪声影响,难以实现极端微弱反射光条件下的振动信号测量。针对以上问题,文中采用光学偏振控制方法,对信号光与本振光的偏振性进行控制,以减少光学噪声的干扰;采用平衡外差探测,将低频直流信号转变为高频交流信号,避免信号被噪声湮没的同时,克服了光电流共模噪声的影响。在赫兹(~10 Hz)频段,探测器的噪声水平达到了散粒噪声极限,并实现了阿瓦量级反射光条件下的微振动信号测量,测得的物体微振动振幅为11.44 nm,A类标准不确定度为0.25 nm,合成不确定度为0.34 nm,测量精度为±0.75 nm。该方案不仅为微弱多普勒频率测量、振动检测等测量领域的研究提供了实验支持,在弱反光、长距离、雨雾天气等复杂测量环境也具有广阔的应用前景。 展开更多
关键词 微振动 弱反射光 偏振控制 散粒噪声极限 平衡外差探测
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A Construction of Weakly Inverse Semigroups
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作者 Bing Jun YU Yan LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第5期759-784,共26页
Let S° be an inverse semigroup with semilattice biordered set E° of idempotents and E a weakly inverse biordered set with a subsemilattice Ep = { e ∈ E | arbieary f ∈ E, S(f , e) loheain in w(e)} iso... Let S° be an inverse semigroup with semilattice biordered set E° of idempotents and E a weakly inverse biordered set with a subsemilattice Ep = { e ∈ E | arbieary f ∈ E, S(f , e) loheain in w(e)} isomorphic to E° by θ:Ep→E°. In this paper, it is proved that if arbieary f, g ∈E, f ←→ g→→ f°θD^s° g°θand there exists a mapping φ from Ep into the symmetric weakly inverse semigroup P J(E∪ S°) satisfying six appropriate conditions, then a weakly inverse semigroup ∑ can be constructed in P J(S°), called the weakly inverse hull of a weakly inverse system (S°, E, θ, φ) with I(∑) ≌ S°, E(∑) ∽- E. Conversely, every weakly inverse semigroup can be constructed in this way. Furthermore, a sufficient and necessary condition for two weakly inverse hulls to be isomorphic is also given. 展开更多
关键词 weakly inverse semigroup VP(Vagner-Preston's) representation weakly inverse biorderedset weakly inverse system weakly inverse hull
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南京长江第三大桥软岩桩基承载性能试验研究 被引量:30
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作者 程晔 龚维明 薛国亚 《土木工程学报》 EI CSCD 北大核心 2005年第12期94-98,114,共6页
介绍南京长江第三大桥软岩桩基的试验研究情况。试桩的嵌岩深度大,承载力高。针对当地的地质情况和工程需要,采用适当的施工工艺。静载试验使用自平衡法,根据试验结果对原设计进行优化,达到桩基试验的目的。
关键词 软岩桩基 自平衡 优化
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提高基于TDLAS的废气动态浓度测量系统分辨率与灵敏度的方法 被引量:4
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作者 肖兵 梁瑛琳 +1 位作者 叶一如 薛琦 《仪表技术与传感器》 CSCD 北大核心 2009年第5期99-102,共4页
基于自平衡激光接收器和数字锁定放大器构造了TDLAS汽车尾气动态浓度测量系统。其中,自平衡激光接收器通过引入一个低频反馈回路去维持吸收信号和参考信号的自动平衡,有效地消除了背景噪音,扩大了测量范围;而数字锁定放大器采用一块DSP... 基于自平衡激光接收器和数字锁定放大器构造了TDLAS汽车尾气动态浓度测量系统。其中,自平衡激光接收器通过引入一个低频反馈回路去维持吸收信号和参考信号的自动平衡,有效地消除了背景噪音,扩大了测量范围;而数字锁定放大器采用一块DSP芯片TMS320F2812来实现相关检测算法,大大降低了系统的白噪音,提高了测量灵敏度。 展开更多
关键词 微弱信号 自平衡激光接收器 数字锁定放大器
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广义算子半群渐近行为及其强弱稳定性 被引量:2
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作者 仓定帮 陈藏 葛世刚 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第2期62-65,共4页
首先给出了由Banach空间有界线性算子引导的广义算子半群的定义及其性质;其次研究广义算子半群的渐近表达式;最后研究了广义算子半群的强弱稳定性,给出了广义算子半群强弱稳定性等价的条件。
关键词 广义算子半群 渐近行为 强稳定性 弱稳定性
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裂缝性有水气藏水侵量预测方法 被引量:11
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作者 陈军 敖耀庭 张爱华 《特种油气藏》 CAS CSCD 2010年第2期66-68,共3页
川南地区单裂缝系统有水气藏大多属于弱弹性水驱,水区规模较小,计算该类型气藏水侵量时,通常使用方法、条件不适合,相关气藏储层参数不易获得,其应用受到极大限制。在分析研究某典型裂缝性有水气藏多年气水产量数据后,应用不同方法估算... 川南地区单裂缝系统有水气藏大多属于弱弹性水驱,水区规模较小,计算该类型气藏水侵量时,通常使用方法、条件不适合,相关气藏储层参数不易获得,其应用受到极大限制。在分析研究某典型裂缝性有水气藏多年气水产量数据后,应用不同方法估算气藏的水侵量,结合气藏生产实际,对比分析后认为,物质平衡法能够很好地适应该类裂缝系统,不仅可以估算各个时期的水侵量,而且可以估算水体规模,预测最大水侵量,对于指导该类气藏的后续生产规划具有现实意义。 展开更多
关键词 裂缝性气藏 弱弹性水驱 水侵量 物质平衡法
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用于高速微弱光信号的平衡探测技术研究 被引量:4
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作者 刘宏阳 张燕革 +2 位作者 艾勇 代永红 陈晶 《激光技术》 CAS CSCD 北大核心 2015年第2期182-184,共3页
长距离高速微弱光电探测技术在激光通信中应用广泛。为了在未被噪声湮没的环境中检测出所需的微弱信号,采用平衡探测技术对单管探测和平衡探测进行对比,并且对具体的平衡探测器电路进行了理论分析和仿真,得出了在一致性系数较大(k>0... 长距离高速微弱光电探测技术在激光通信中应用广泛。为了在未被噪声湮没的环境中检测出所需的微弱信号,采用平衡探测技术对单管探测和平衡探测进行对比,并且对具体的平衡探测器电路进行了理论分析和仿真,得出了在一致性系数较大(k>0.6)时平衡探测器的信噪比优于单管探测的结论。从理论上分析了单管和双管探测的最小可探测光功率。结果表明,把平衡探测技术用于高速微弱光信号探测具有很大的优越性。 展开更多
关键词 探测器 高速微弱光信号 平衡探测 信噪比
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